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BACKGROUND: Sciatic nerve repair becomes a focus of research in neurological aspect to restore the normal physical ability of the animal to stand and walk. Tissue engineered nerve grafts (TENGs) provide a promising alternative therapy for regeneration of large gap defects. The present study investigates the regenerative capacity of PRP, ADSCs, and PRP mixed ADSCs on a long sciatic nerve defect (40-mm) bridged by a polyglycolic polypropylene (PGA-PRL) mesh which acts as a neural scaffold. MATERIALS AND METHODS: The study was conducted on 12 adult male mongrel dogs that were randomly divided into 4 groups: Group I (scaffold group); where the sciatic defect was bridged by a (PGA-PRL) mesh only while the mesh was injected with ADSCs in Group II (ADSCs group), PRP in Group III (PRP group). Mixture of PRP and ADSCs was allocated in Group IV (PRP + ADSCs group). Monthly, all animals were monitored for improvement in their gait and a numerical lameness score was recorded for all groups. 6 months-post surgery, the structural and functional recovery of sciatic nerve was evaluated electrophysiologically, and on the level of gene expression, and both sciatic nerve and the gastrocnemius muscle were evaluated morphometrically, histopathologically. RESULTS: Numerical lameness score showed improvement in the motor activities of both Group II and Group III followed by Group IV and the scaffold group showed mild improvement even after 6 months. Histopathologically, all treated groups showed axonal sprouting and numerous regenerated fascicles with obvious angiogenesis in proximal cut, and distal portion where Group IV exhibited a significant remyelination with the MCOOL technique. The regenerative ratio of gastrocnemius muscle was 23.81%, 56.68%, 52.06% and 40.69% for Group I, II, III and IV; respectively. The expression of NGF showed significant up regulation in the proximal portion for both Group III and Group IV (P ≤ 0.0001) while Group II showed no significant difference. PDGF-A, and VEGF expressions were up-regulated in Group II, III, and IV whereas Group I showed significant down-regulation for NGF, PDGF-A, and VEGF (P ≤ 0.0001). CONCLUSION: ADSCs have a great role in restoring the damaged nerve fibers by secreting several types of growth factors like NGF that have a proliferative effect on Schwann cells and their migration. In addition, PRP therapy potentiates the effect of ADSCs by synthesis another growth factors such as PDGF-A, VEGF, NGF for better healing of large sciatic gap defects.
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Regeneración Nerviosa , Polipropilenos , Nervio Ciático , Animales , Perros , Regeneración Nerviosa/fisiología , Nervio Ciático/lesiones , Masculino , Polipropilenos/química , Plasma Rico en Plaquetas/metabolismo , Tejido Adiposo/citología , Ácido Poliglicólico/química , Células Madre/citología , Células Madre/metabolismo , Modelos Animales de Enfermedad , Andamios del Tejido/química , Trasplante de Células Madre/métodos , Ingeniería de Tejidos/métodosRESUMEN
A single injection of platelet-rich plasma (PRP) or stromal vascular fraction (SVF) in treating neurological ailments suggests promise; however, there is limited evidence of the efficacy of combination therapy. This trial aimed to determine whether combining SVF and PRP could provide further therapeutic effects in treating multiple sclerosis (MS). Fifteen Persian cats were separated into three groups (n = 5): group I (control negative), and group II (control positive); EB was injected intrathecally into the spinal cord and then treated 14 days later with intrathecal phosphate buffered saline injection, and group III (SVF + PRP), cats were injected intrathecally with EB through the spinal cord, followed by a combination of SVF and PRP 14 days after induction. Therapeutic effects were evaluated using the Basso-Beattie-Bresnahan scale throughout the treatment timeline and at the end. Together with morphological, MRI scan, immunohistochemical, transmission electron microscopy, and gene expression investigations. The results demonstrated that combining SVF and PRP successfully reduced lesion intensity on gross inspection and MRI. In addition to increased immunoreactivity to Olig2 and MBP and decreased immunoreactivity to Bax and GFAP, there was a significant improvement in BBB scores and an increase in neurotrophic factor (BDNF, NGF, and SDF) expression when compared to the positive control group. Finally, intrathecal SVF + PRP is the most promising and safe therapy for multiple sclerosis, resulting in clinical advantages such as functional recovery, MRI enhancement, and axonal remyelination.
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Esclerosis Múltiple , Plasma Rico en Plaquetas , Traumatismos de la Médula Espinal , Animales , Gatos , Proteína X Asociada a bcl-2 , Fracción Vascular Estromal , Esclerosis , Factores de Crecimiento NerviosoRESUMEN
The major efforts to improve feed conversion, increase the body weight and breast muscle yield of broilers have been focused on feeding and management at the post hatch period. However, incubation temperature is the most significant factor for the egg hatching rate, chick quality, and post hatch performance. Therefore, incubation factors affecting the performance should be taken with necessary precautions. Incubation temperature not only affects the early development of the hatchlings but also has a lasting impact on the characteristics of the chicks, such as final body weight and meat quality traits. This article provides an overview about embryonic thermal manipulation (TM) of domestic fowls and review the lucrative and deleterious effects of embryonic TM on embryo development, muscle growth, thermotolerance acquisition, and immunity.
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Pollos , Aves de Corral , Animales , Pollos/fisiología , Temperatura , Peso Corporal/fisiología , CarneRESUMEN
BACKGROUND: The testes are highly susceptible to the adverse effects of chemotherapy and radiation at all stages of life. Exposure to these threats mainly occurs during cancer treatment and as an occupational hazard in radiation centers. The present study investigated the regenerative ability of adipose-derived mesenchymal stem cells (ADMSCs) against the adverse effects of cisplatin on the structure and function of the testes. METHODS: New Zealand white rabbits (N = 15) were divided into three groups of five: a negative control group (no treatment), a cisplatin group (single dose of cisplatin into each testis followed three days later by a PBS injection), and a cisplatin + ADMSCs group (cisplatin injection followed three days later by an ADMSC injection). On day 45 post-treatment, serum testosterone levels were evaluated, and the testes and epididymis were collected for histology, oxidative stress examination, and epididymal sperm analysis. RESULTS: Cisplatin caused damage to the testicular tissue and decreased serum testosterone levels, epididymal sperm counts, and oxidants. An antioxidant imbalance was detected due to increasing malondialdehyde (MDA) and reduced glutathione (GSH) levels in testicular tissue. The ADMSC-treated group displayed a moderate epididymal sperm count, adequate antioxidant protection, suitable hormone levels, and enhanced testicular tissue morphology. CONCLUSIONS: ADMSCs treatment repaired damaged testicular tissue, enhanced biochemical parameters, and modified pathological changes caused by cisplatin.
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Azoospermia , Células Madre Mesenquimatosas , Masculino , Animales , Conejos , Humanos , Testículo/metabolismo , Cisplatino/efectos adversos , Antioxidantes/farmacología , Azoospermia/inducido químicamente , Azoospermia/metabolismo , Azoospermia/patología , Semen , Espermatozoides/metabolismo , Espermatozoides/patología , Estrés Oxidativo , Testosterona/farmacologíaRESUMEN
BACKGROUND: Multiple sclerosis (MS) is the most frequent non-traumatic neurological debilitating disease among young adults with no cure. Over recent decades, efforts to treat neurodegenerative diseases have shifted to regenerative cell therapy. Adipose tissue-derived stromal vascular fraction (SVF) comprises a heterogeneous cell population, considered an easily accessible source of MSCs with therapeutic potential in autoimmune diseases. This study aimed to assess the regenerative capacity of low-level laser-activated SVF in an MS cat model. METHODS: Fifteen adult Persian cats were used in this study: Group I (control negative group, normal cats), Group II (EB-treated group, induced for MS by ethidium bromide (EB) intrathecal injection), and Group III (SVF co-treated group, induced for MS then treated with SVF on day 14 post-induction). The SVF was obtained after digesting the adipose tissue with collagenase type I and injecting it intrathecal through the foramen magnum. RESULTS: The results showed that the pelvic limb's weight-bearing locomotion activity was significantly (P ≤ 0.05) recovered in Group III, and the Basso, Beattie, and Bresnahan (BBB) scores of hindlimb locomotion were significantly higher in Group III (14 ± 0.44) than Group II (4 ± 0.31). The lesion's extent and intensity were reduced in the magnetic resonance imaging (MRI) of Group III. Besides, the same group showed a significant increase in the expression of neurotrophic factors: BDNF, SDF and NGF (0.61 ± 0.01, 0.51 ± 0.01 and 0.67 ± 0.01, respectively) compared with Group II (0.33 ± 0.01, 0.36 ± 0.006 and 0.2 ± 0.01, respectively). Furthermore, SVF co-treated group revealed a significant (P ≤ 0.05) increase in oligodendrocyte transcription factor (Olig2) and myelin basic protein (4 ± 0.35 and 6 ± 0.45, respectively) that was decreased in group II (1.8 ± 0.22 and 2.9 ± 0.20, respectively). Moreover, group III showed a significant (P ≤ 0.05) reduction in Bax and glial fibrillary acidic protein (4 ± 0.53 and 3.8 ± 0.52, respectively) as compared with group II (10.7 ± 0.49 and 8.7 ± 0.78, respectively). The transmission electron microscopy demonstrated regular more compact, and markedly (P ≤ 0.05) thicker myelin sheaths (mm) in Group III (0.3 ± 0.006) as compared with group II (0.1 ± 0.004). Based on our results, the SVF co-treated group revealed remyelination and regeneration capacity with a reduction in apoptosis and axonal degeneration. CONCLUSION: SVF is considered an easy, valuable, and promising therapeutic approach for treating spinal cord injuries, particularly MS.
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Esclerosis Múltiple , Traumatismos de la Médula Espinal , Gatos , Animales , Esclerosis Múltiple/terapia , Fracción Vascular Estromal , Traumatismos de la Médula Espinal/terapia , Tejido Adiposo , Células del EstromaRESUMEN
Infertility is a serious medical, economic, and psychological problem in the society. Male factor infertility, due to defective spermatogenesis as a result of a failure in germ cell proliferation and differentiation, appears to be the cause of 25-50% of infertility cases. According to several surveys, testicular degeneration can be caused by a variety of physical, chemical, and microbial causes. A stem cell is a non-specialized cell which is characterized by self-renewal by mitotic cell division and able to differentiate to specialized cells for the various tissues of the body. The data were obtained and analyzed from different databases (PubMed, Google Scholar, Egyptian Knowledge Bank, Elsevier, Medline, Embase, ProQuest, and BMC). This review discusses the causes, symptoms, and grades of testicular degeneration and the use of different types of stem cells in regeneration. And its conclusion based on previous researches and trials, MSCs are considered effective therapy for testicular degeneration.
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Infertilidad Masculina , Testículo , Humanos , Animales , Masculino , Testículo/metabolismo , Espermatogénesis , Células Madre/metabolismo , Infertilidad Masculina/terapia , Infertilidad Masculina/metabolismo , Animales de Laboratorio , RegeneraciónRESUMEN
BACKGROUND: The testes are highly susceptible to the adverse effects of chemotherapy and radiation at all stages of life. Exposure to these threats mainly occurs during cancer treatment and as an occupational hazard in radiation centers. The present study investigated the regenerative ability of adipose-derived mesenchymal stem cells (ADMSCs) against the adverse effects of cisplatin on the structure and function of the testes. METHODS: New Zealand white rabbits (N = 15) were divided into three groups of five: a negative control group (no treatment), a cisplatin group (single dose of cisplatin into each testis followed three days later by a PBS injection), and a cisplatin + ADMSCs group (cisplatin injection followed three days later by an ADMSC injection). On day 45 post-treatment, serum testosterone levels were evaluated, and the testes and epididymis were collected for histology, oxidative stress examination, and epididymal sperm analysis. RESULTS: Cisplatin caused damage to the testicular tissue and decreased serum testosterone levels, epididymal sperm counts, and oxidants. An antioxidant imbalance was detected due to increasing malondialdehyde (MDA) and reduced glutathione (GSH) levels in testicular tissue. The ADMSC-treated group displayed a moderate epididymal sperm count, adequate antioxidant protection, suitable hormone levels, and enhanced testicular tissue morphology. CONCLUSIONS: ADMSCs treatment repaired damaged testicular tissue, enhanced biochemical parameters, and modified pathological changes caused by cisplatin.
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Humanos , Animales , Masculino , Conejos , Azoospermia/inducido químicamente , Azoospermia/metabolismo , Azoospermia/patología , Semen , Espermatozoides/metabolismo , Espermatozoides/patología , Testículo/metabolismo , Testosterona/farmacología , Cisplatino/efectos adversos , Estrés Oxidativo , Células Madre Mesenquimatosas , Antioxidantes/farmacologíaRESUMEN
BACKGROUND: Cartilaginous disorders comprise a wide range of diseases that affect normal joint movement, ear and nose shape; and they have great social and economic impact. Mesenchymal stem cells (MSCs) provide a promising regeneration alternative for treatment of degenerative cartilaginous disorders. This study aimed to compare therapeutic potential of different types of laser activated MSCs to promote auricular cartilage regeneration. Twelve adult rabbit allocated equally in four groups, all animals received a surgical mid auricular cartilage defect in one ear; Group I (Positive control) injected sub-perichondrially with phosphate-buffered saline (PBS), Group II (ADMSC-transplanted group) injected adipose-derived MSCs (ADMSCs), Group III (BMMSCs-transplanted group) received bone marrow-derived MSCs (BMMSCs), and Group IV (EMSC-transplanted group) received ear MSCs (EMSCs) in the defected ear. The auricular defect was analyzed morphologically, histopathologically and immunohistochemically after 4 weeks. In addition, a quantitative real-time polymerase chain reaction was used to examine expression of the collagen type II (Col II) and aggrecan as cartilage growth factors. RESULTS: The auricles of all treatments appeared completely healed with smooth surfaces and similar tissue color. Histopathologically, defective areas of control positive group, ADMSCs and EMSCs treated groups experienced a small area of immature cartilage. While BMMSCs treated group exhibited typical features of new cartilage formation with mature chondrocytes inside their lacunae and dense extracellular matrix (ECM). In addition, BMMSC treated group showed a positive reaction to Masson's trichrome and orcein stains. In contrary, control positive, ADMSC and EMSC groups revealed faint staining with Masson's trichrome and Orcein. Immunohistochemically, there was an intense positive S100 expression in BMMSCs (with a significant increase of area percentage + 21.89 (P < 0.05), a moderate reaction in EMSCs (with an area percentage + 17.97, and a mild reaction in the control group and ADMSCs (area percentages + 8.02 and + 11.37, respectively). The expression of relative col II and aggrecan was substantially highest in BMMSCs (± 0.91 and ± 0.89, respectively). While, Control positive, ADMSCs and EMSCs groups recorded (± 0.41: ± 0.21, ± 0.6: ± 0.44, ± 0.61: ± 0.63) respectively. CONCLUSION: BMMSCs showed the highest chondrogenic potential compared to ADMSCs and EMSCs and should be considered the first choice in treatment of cartilaginous degenerative disorders.
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Cartílago Auricular , Células Madre Mesenquimatosas , Animales , Conejos , Agrecanos/metabolismo , Condrocitos , Matriz Extracelular , Células Cultivadas , Diferenciación CelularRESUMEN
BACKGROUND: Multiple sclerosis (MS) is a progressive autoimmune demyelinating disease of the central nervous system. To date, there is no effective therapy for it. Our study aimed to determine the potential role of platelet-rich plasma (PRP) in the treatment of MS in cats. METHODS: The current study was conducted on 15 adult Persian cats that were divided into three groups: control negative, control positive (ethidium bromide (EB)-treated group), and PRP co-treated group (EB-treated group intrathecally injected with PRP on day 14 post-spinal cord injury). PRP was obtained by centrifuging blood on anticoagulant citrate dextrose and activating it with red and green laser diodes. The Basso-Beattie-Bresnahan (BBB) scores were used to assess the motor function recovery on days 1, 3, 7, 14, 20, and 28 following 14 days from EB injection. Moreover, magnetic resonance imaging (MRI) analysis, histopathological investigations, transmission electron microscopy (TEM) studies, and immunohistochemical analysis were conducted, and the gene expressions of nerve growth factors (NGFs), brain-derived neurotrophic factors (BDNF), and stromal cell-derived factors (SDF) were evaluated. RESULTS: Our results indicated that PRP had a significant ameliorative effect on the motor function of the hindlimbs as early as day 20 and so on. MRI revealed that the size and intensity of the lesion were significantly reduced in the PRP co-treated group. The histopathological and TEM investigations demonstrated that the PRP co-treated group had a significant improvement in the structure and organization of the white matter, as well as a high remyelination capacity. Furthermore, a significant increase in myelin basic protein and Olig2 immunoreactivity as well as a reduction in Bax and glial fibrillar acidic protein immune markers was observed. NGFs were found to be upregulated by gene expression. CONCLUSION: As a result, we concluded that the intrathecal injection of PRP was an effective, safe, and promising method for the treatment of MS.
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BACKGROUND Cancer is a life-threatening disease that affects approximately 18 million individuals worldwide. Breast cancer is the most common female neoplasm globally with more than 276,480 new cases of invasive breast cancer expected to be diagnosed in women in the U.S. alone in 2020. Genetic and epigenetic factors play role in the carcinogenesis and progression of this disease. In this study, MCF-7 adenocarcinoma cells were transfected with CRISPR/Cas9 plasmid to either knock out CDK11 or to activate CDH1. Treated cells were allografted into the mammary glands of female rats (150190 g, 68 weeks) to evaluate the capability of these cells to control cancer progression and metastasis. RESULTS qPCR data revealed a significant downregulation of CDK11 and upregulation of CDH1. Cell cycle analysis and apoptosis assays indicated the knockout of CDK11 and simultaneous activation of CDH1 resulted in cell cycle arrest at G2/M phase and accumulation of cells at G2. Meanwhile, the percentage of cells that underwent late apoptosis increased in both genome editing hits. Histopathological sectioning data indicated that untransfected MCF-7 cells were capable of developing tumors in the mammary gland and initiation g angiogenesis. Transfected cells significantly restricted cancer cell infiltration/invasion by minimally localizing tumors and inhibiting angiogenesis. CONCLUSIONS Although further investigation is needed, the present data indicate the potentiality of using CRISPR/Cas9-based therapy as a promising approach to treat breast cancer. Impact: these data indicate targeting cancer-related genes via any genome editing tool might represent a novel approach to combat cancer.
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Animales , Femenino , Ratas , Neoplasias de la Mama/genética , Adenocarcinoma/genética , Proteínas Cdh1/genética , Proteína 9 Asociada a CRISPR/genética , Neoplasias de la Mama/secundario , Ratas Sprague-DawleyRESUMEN
Cyclophosphamide is anticancer drug with a well-Known nephrotoxicity. This work was applied to study the lucrative antioxidant influence of metformin as co-therapy on the nephrotoxicity induced by cyclophosphamide in the treatment of different cancer diseases. Four groups of male Sprague Dawley rats were used; Control group (C) received single I.P. injection of 0.2 ml saline, Metformin (MET) group received daily gavage of 200 mg/kg metformin for two weeks, Cyclophosphamide (CP) group received single I.P. injection of 200 mg/kg CP, Protector group (CP.MET) received daily gavage of 200 mg/kg metformin for two weeks and single I.P. injection of 200 mg/kg CP at day 7. By day 14 rats were euthanized. Samples were collected from kidney tissues and blood for kidney function evaluation, histopathological and assessment of oxidative stress markers. The results disclosed that CP yields many functional and structural damage to the kidney, worsened oxidative stress markers and kidney function indicators. The protector group displayed better kidney tissue morphology, acceptable kidney function indicators as well as satisfactory oxidative stress markers. In assumption, metformin could be combined with CP owing to its lucrative effect counter to CP persuaded nephrotoxicity.
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Embryonic thermal manipulation led to several modifications in molecular, physiological, and biochemical parameters which affect pre- and post-hatch growth performance. The current study aims to elucidate the onset and long-term effects of intermittent thermal manipulations (TM) during two-time windows, early/late, of embryogenesis in Japanese quail (Coturnix japonica) on embryonic development, hatchability, muscle histogenesis, and post-hatch growth performance. Four groups were created; quail eggs in the control group were incubated at 37.7 °C and relative humidity (RH) 55%. Three thermally treated groups were incubated intermittently at 41 °C and 65% RH intermittently (3 h/day): early embryogenesis group (EE) was thermally treated during embryonic days (ED) 6-8, late embryogenesis group (LE) was thermally treated during (ED12-ED14), and early and late embryogenesis group (EL) was thermally manipulated in both time windows. Relative embryo weights in EL and EE were significantly lighter than those in LE and Ctrl groups. The hatched chicks were reared under optimal managemental conditions (three replicates per treatment). Average daily feed intake was recorded, and feed conversion ratio (FCR) was calculated. Histological and quantitative analyses of muscle fibers were performed. The results revealed that TM led to significant hypertrophy of quail breast muscle in (EE). Intermittent short-term (3-6 h) thermal manipulation (39-40 °C) protocols during early embryogenesis (ED6-ED8) could be recommended to enhance muscle mass growth and breast muscle yield in the Japanese quail.
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Coturnix , Óvulo , Animales , Pollos , Desarrollo Embrionario , CodornizRESUMEN
BACKGROUND: Spinal cord injury (SCI) is a serious neurological spinal cord damage that resulted in the loss of temporary or permanent function. However, there are even now no effective therapies for it. So, a new medical promising therapeutic hotspot over the previous decades appeared which was (Stem cell (SC) cure of SCI). Otherwise, animal models are considered in preclinical research as a model for humans to trial a potential new treatment. METHODOLOGY: Following articles were saved from different databases (PubMed, Google scholar, Egyptian knowledge bank, Elsevier, Medline, Embase, ProQuest, BMC) on the last two decades, and data were obtained then analyzed. RESULTS: This review discusses the type and grading of SCI. As well as different types of stem cells therapy for SCI, including mesenchymal stem cells (MSCs), neural stem cells (NSCs), hematopoietic stem cells (HSCs), induced pluripotent stem cells (iPSCs), and embryonic stem cells (ESCs). The review focuses on the transplantation pathways, clinical evaluation, and clinical signs of different types of SC on different animal models which are summarized in tables to give an easy to reach. CONCLUSION: Pharmacological and physiotherapy have limited regenerative power in comparison with stem cells medication in the treatment of SCI. Among several sources of cell therapies, mesenchymal stromal/stem cell (MSC) one is being progressively developed as a trusted important energetic way to repair and regenerate. Finally, a wide-ranged animal models have been condensed that helped in human clinical trial therapies.
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The present study aimed to investigate the effects of Bone marrow derived pancreatic progenitor cells (BM- PPCs) in diabetic rats. It was conducted on 30 adult male Sprague-Dawley rats weighing 200-220â¯g. They were divided into three groups: (a) Group 1 was the control group; (b) Group 2 was the diabetic (induced diabetic by a single intraperitoneal (IP) injection of streptozotocin (STZ) (60 mg/kg) and (c) Group 3 was the treated (received injection of 2.5 X 106 BM- PPCs via the tail vein twice with a 21-day time interval). The blood glucose level was estimated weekly, the oxidative stress and insulin gene expression were evaluated at the end of the experiment. Pancreatic tissue histopathology was performed. The insulin immuno-histochemical reaction was applied to the islets. The blood glucose level was reduced in the treated group over time till reaching its acceptable level whereas it was increased in the diabetic group. The oxidative stress was decreased in the treated group compared to the diabetic one. The treated group showed increased expression of the insulin gene compared to the diabetic group. The immune-histochemical analysis of insulin showed an increased number and size of pancreatic islets in the treated group compared to the diabetic one. Thus, the twofold injection of BM- PPCs could restore the normal beta-cell morphology and function.
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Diabetes Mellitus , Hiperglucemia/terapia , Islotes Pancreáticos/citología , Trasplante de Células Madre Mesenquimatosas , Células Madre , Animales , Diabetes Mellitus/inducido químicamente , Citometría de Flujo , Insulina/genética , Insulina/metabolismo , Masculino , Estrés Oxidativo , Ratas , Ratas Sprague-Dawley , Estándares de ReferenciaRESUMEN
Endoscopy of the upper respiratory tract (URT) is one of the minimally invasive techniques used for diagnosis and treatment of diseases in horses. Training in the use of an endoscope follows an apprenticeship approach, with extensive practice needed to help achieve effective skills acquisition. The use of live animals for training presents the risk of injury to both the animal and the trainee. The increased number of students and practitioners, a shortage of facilities, and limited time available from expert clinicians add more challenges to the training process. In this work, we focused on the development of a preserved head and neck model that can be used as an effective training tool for training novices on the basics of upper respiratory endoscopy. The aim of the training is to become familiar with handling the endoscope and identification of the endoscopic depictions of normal anatomical structures encountered in the upper respiratory tract. Using the model, anatomical structures were clearly visible, recognized by their shape, architecture and topographical location. The model solved many of the aforementioned practical challenges, and has great potential as a replacement alternative to the use of live animals. There are opportunities for the application of such models intraining other clinical skills and for a variety of species.