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1.
Front Bioeng Biotechnol ; 10: 891166, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910019

RESUMO

Due to the well-known biocompatibility, tunable biodegradability, and mechanical properties, silk fibroin hydrogel is an exciting material for localized drug delivery systems to decrease the therapy cost, decrease the negative side effects, and increase the efficiency of chemotherapy. However, the lack of remote stimuli response and active drug release behavior has yet to be analyzed comparatively. In this study, we developed magnetic silk fibroin (SF) hydrogel samples through the facile blending method, loaded with doxorubicin hydrochloride (DOX) and incorporated with different concentrations of iron oxide nanoparticles (IONPs), to investigate the presumable ability of controlled and sustained drug release under the various external magnetic field (EMF). The morphology and rheological properties of SF hydrogel and magnetic SF hydrogel were compared through FESEM images and rheometer analysis. Here, we demonstrated that adding magnetic nanoparticles (MNPs) into SFH decreased the complex viscosity and provided a denser porosity with a bigger pore size matrix structure, which allowed the drug to be released faster in the absence of an EMF. Release kinetic studies show that magnetic SF hydrogel could achieve controlled release of DOX in the presence of an EMF. Furthermore, the drug release from magnetic SF hydrogel decreased in the presence of a static magnetic field (SMF) and an alternating magnetic field (AMF), and the release rate decreased even more with the higher MNPs concentration and magnetic field strength. Subsequently, Wilms' tumor and human fibroblast cells were cultured with almost the same concentration of DOX released in different periods, and cell viability was investigated using MTT assay. MTT results indicated that the Wilms' tumor cells were more resistant to DOX than the human fibroblasts, and the IC50 values were calculated at 1.82 ± 0.001 and 2.73 ± 0.004 (µg/ml) for human fibroblasts and Wilms' tumor cells, respectively. Wilms' tumor cells showed drug resistance in a higher DOX concentration, indicating the importance of controlled drug delivery. These findings suggest that the developed magnetic SFH loaded with DOX holds excellent potential for intelligent drug delivery systems with noninvasive injection and remotely controlled abilities.

2.
Cell Tissue Bank ; 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35792989

RESUMO

AIMS: This study was designed to provide both ex-vivo and in-vivo methods for the extraction and expansion of spermatogonial stem cells (SSCs). METHODS: For in-vivo experiments, azoospermic mouse model was performed with Busulfan. Isolation, culture, and characterization of neonate mouse SSC were also achieved. We performed an in-vivo injection of labeled SSCs to the testes with azoospermia. In ex-vivo experiments, extracted SSCs were seeded on the fabricated scaffold consisting of hyaluronic acid (HA) and decellularized testis tissues (DTT). Immunofluorescence staining with PLZF, TP1, and Tekt 1 was performed for SSCs differentiation and proliferation. RESULTS: Several studies demonstrated efficient spermatogenic arrest in seminiferous tubules and proved the absence of spermatogenesis. Transplanted SSCs moved and settled in the basement covering the seminiferous tubules. Most of the cells were positive for Dil, after 4 weeks. An epithelium containing spermatogonia-like cells with Sertoli-like, and Leydig cells were evident in the seminiferous tubules of biopsies, and the IHC staining was significantly positive, 4 weeks after injection of SSCs. The results of the ex-vivo experiments showed positive staining for all markers, which was significantly enhanced in scaffolds of ex-vivo experiments compared with in-vitro seeded scaffolds. CONCLUSION: Ex-vivo SSC differentiation and proliferation using cell-seeded microfluidic testis scaffolds maybe effective for treatment of the azoospermia.

3.
Neurourol Urodyn ; 2022 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-35842827

RESUMO

OBJECTIVE: Neurogenic lower urinary tract dysfunction (NLUTD), a challenging disorder, is defined by lack of bladder control due to the abnormalities in neural pathways and can be classified based on the location of lesions within the nervous system, thus investigating the neural pathways can help us to know the site of the lesion and specify the class of the NLUTD. Diffusion Tensor Imaging (DTI) tractography, a noninvasive advanced imaging method, is capable of detecting central nervous system pathologies, even if routine magnetic resonance imaging shows no abnormality. Accordingly, tractography is an ideal technique to evaluate patients with NLUTD and visualize the pathology site within the spine. This study aimed to introduce a novel method of spinal cord injury (SCI) to establish NLUTD in the rabbit and to investigate the potential of tractography in tracing neural tracts of the spinal cord in an induced NLUTD animal model. MATERIALS AND METHODS: An animal model of NLUTD was induced through cauterization of the spinal cord at the level T12-L1 in 12 rabbits. Then rabbits were assessed via DTI, urodynamic studies (UDS), voiding cystourethrogram (VCUG), and pathology assessments using antineurofilament 200 (NF200) antibody, anti-S100, anti-Smooth Muscle Actin, anti-Myogenin, and anti-MyoD1. RESULTS: The tractography visualized lesions within spinal cord fibers. DTI parameters including fractional anisotropy (FA) value and tract density were significantly decreased (FA: p-value = 0.01, Tract density: p-value = 0.05) after injury. The mean diffusivity (MD) was insignificantly increased compared to before the injury. Also, the results of UDS and pathology assessments corroborated that applying SCI and the establishment of the NLUTD model was completely successful. CONCLUSION: In the present study, we investigated the auxiliary role of tractography in detecting the spinal cord lesions in the novel established rabbit model of NLUTD. The introduced method of NLUTD induction was without the leg's neurological deficit, easily applicable, low-cost, and was accompanied by minimal surgical preparation and a satisfactory survival rate in comparison with other SCI animal models.

4.
Int Urol Nephrol ; 54(9): 2187-2195, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35776255

RESUMO

AIM: In this study, we aimed to develop a novel alternative to buccal mucosal graft from the acellular human fetal skin to manage hypospadias in a rabbit model. We optimized the decellularization protocol to develop and characterize the human tissue-engineered fetal dermal matrix as an "off-the-shelf" natural biomaterial. MATERIAL AND METHODS: Human fetal skin was obtained at 16-19 weeks gestational age with respect to a signed informed consent from parents under the university ethical committee approval. The dissected full-thickness fetal skin tissues were placed into SDS and Triton X-100 in different dosages to achieve the optimum decellularization protocol. Histopathology of the acellular fetal matrix was assessed by Hematoxylin & Eosin (H&E) and DAPI staining to confirm the removal of all cell materials, Masson's trichrome staining for collagen evaluation, DNA quantification for confirmation of DNA content, and scanning electron microscopy (SEM) for evaluation of scaffold microstructure. Immunohistochemistry (IHC) staining was used to detect specific dermal markers, namely vimentin, type I collagen, cytokeratin (CK)19. The prepared dermal scaffolds were then grafted on the 8 rabbit models of hypospadias. The rabbits underwent evaluations at 1, 2, 3, and 6 months postoperatively. RESULTS: H&E, Masson's trichrome, DAPI staining, and SEM confirmed the significant removal of cells; meanwhile, the ECM was completely preserved. At the time of biopsy, after 2, 4, and 6 months, no evidence of inflammation, fibrosis, necrosis, or rejection was observed. The grafted dermal scaffolds appeared histologically and anatomically normal. It was observed that the scaffolds were recellularized by circulating CD 34 + bone marrow stem cells (BMSCs) inside the body, implicating the body as a natural bioreactor. CONCLUSION: The application of acellular fetal skin (AFS) is a safe and feasible method that can decrease surgical time in a complex hypospadias reconstruction. Moreover, AFS demonstrated excellent angiogenesis characteristics and migration of the stem cells to the scaffold observed during the course of treatment. Novel natural AFS scaffold without cell seeding is an excellent alternative to buccal mucosal graft; hence, it can overcome the limitations concerning the graft size and prevent the creation of wounds in oral mucosal tissue.

5.
Animal Model Exp Med ; 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35726155

RESUMO

Severely immunocompromised NOD.Cg-Prkdcscid Il2rgtm1Sug (NOG) mice are among the ideal animal recipients for generation of human cancer models. Transplantation of human solid tumors having abundant tumor-infiltrating lymphocytes (TILs) can induce xenogeneic graft-versus-host disease (xGvHD) following engraftment and expansion of the TILs inside the animal body. Wilms' tumor (WT) has not been recognized as a lymphocyte-predominant tumor. However, 3 consecutive generations of NOG mice bearing WT patient-derived xenografts (PDX) xenotransplanted from a single donor showed different degrees of inflammatory symptoms after transplantation before any therapeutic intervention. In the initial generation, dermatitis, auto-amputation of digits, weight loss, lymphadenopathy, hepatitis, and interstitial pneumonitis were observed. Despite antibiotic treatment, no response was noticed, and thus the animals were prematurely euthanized (day 47 posttransplantation). Laboratory and histopathologic evaluations revealed lymphoid infiltrates positively immunostained with anti-human CD3 and CD8 antibodies in the xenografts and primary tumor, whereas no microbial infection or lymphoproliferative disorder was found. Mice of the next generation that lived longer (91 days) developed sclerotic skin changes and more severe pneumonitis. Cutaneous symptoms were milder in the last generation. The xenografts of the last 2 generations also contained TILs, and lacked lymphoproliferative transformation. The systemic immunoinflammatory syndrome in the absence of microbial infection and posttransplant lymphoproliferative disorder was suggestive of xGvHD. While there are few reports of xGvHD in severely immunodeficient mice xenotransplanted from lymphodominant tumor xenografts, this report for the first time documented serial xGvHD in consecutive passages of WT PDX-bearing models and discussed potential solutions to prevent such an undesired complication.

6.
Ir J Med Sci ; 2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35657540

RESUMO

BACKGROUND: Despite the simplicity of male circumcision, complications occur frequently. Post-circumcision meatal stenosis is a concerning complication that might require several interventions. AIM: This study aims to evaluate the incidence of meatal stenosis in long-term follow-up, following three common circumcision methods: frenular artery preservation, frenular ligation, and the Plastibell device. METHODS: This study is the continuation of the previous randomized clinical trial, the preliminary abstract of which has been accepted in the annual meeting of the American Urological Association in 2011. However, in this paper, we only included the patients with results of long-term follow-up. Patients were followed for a median of 11 years (range, 7-17). Follow-ups were recorded by evaluation of meatus and signs and symptoms of meatal stenosis. RESULTS: Two hundred six boys (80 neonates and 126 non-neonates) at the time of procedure were included in this study. The circumcision was conducted on 23.3% (48/206) of boys with the Plastibell device (PD) and 39.3% (81/206) of cases with frenular artery preservation (FAP) and 37.4% (77/206) of cases with frenular artery ligation (FAL). Meatal stenosis presented in 13 children during follow-up. Considering the three methods of circumcision, a significant difference in the incidence of meatal stenosis among the types of circumcisions was observed (6.3% in PD and 1.2% in FAP, 11.7% in FAL, P = 0.026). CONCLUSION: The present study revealed that the technique preserving the frenular artery is associated with a significantly lower incidence of meatal stenosis. Hence, the FAP is the recommended technique for circumcision as compared to two other methods.

7.
J Assist Reprod Genet ; 39(6): 1237-1247, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35513746

RESUMO

PURPOSE: The aim of this investigation was to design a perfusion-based decellularization protocol to provide whole human uterine bio-scaffolds with preserved structural and componential characteristics and to investigate the in vivo properties of the decellularized tissues. METHODS: Eight human uteri, donated by brain-dead patients, were decellularized by perfusion of sodium dodecyl sulfate (SDS) through the uterine arteries using a peristaltic pump. The bio-scaffolds were evaluated and compared with native human uterus regarding histological, immunohistochemical, structural, and bio-mechanical properties, in addition to CT angiographies to examine the preservation of the vascular networks. Subsequently, we obtained acellular patches and implanted them on uterine defects of female Wistar rats to investigate the bio-compatibility and regenerative potential of the bio-scaffolds. Finally, we performed immunostaining to investigate the potential role of circulating stem cells in recellularization of the implanted bio-scaffolds. RESULTS: The outcomes of this investigation confirmed the efficacy of the proposed protocol to provide whole human uterine scaffolds with characteristics and extra-cellular matrix components similar to the native human uterus. Subsequent in vivo studies demonstrated the bio-compatibility and the regenerative potential of the scaffolds and suggested a signaling pathway as an underlying mechanism for the regenerative process. CONCLUSIONS: To the best of our knowledge, this investigation provides the first efficient perfusion-based decellularization protocol for the human uterus to obtain whole-organ scaffolds. The outcomes of this investigation could be employed in future human uterus tissue engineering studies which could ultimately result in the development of novel treatments for female infertile patients.


Assuntos
Matriz Extracelular , Tecidos Suporte , Animais , Matriz Extracelular/metabolismo , Feminino , Humanos , Modelos Animais , Ratos , Ratos Wistar , Engenharia Tecidual , Tecidos Suporte/química , Útero
8.
Front Bioeng Biotechnol ; 10: 805299, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35547166

RESUMO

Reproduction of different tissues using scaffolds and materials is a major element in regenerative medicine. The regeneration of whole organs with decellularized extracellular matrix (dECM) has remained a goal despite the use of these materials for different purposes. Recently, decellularization techniques have been widely used in producing scaffolds that are appropriate for regenerating damaged organs and may be able to overcome the shortage of donor organs. Decellularized ECM offers several advantages over synthetic compounds, including the preserved natural microenvironment features. Different decellularization methods have been developed, each of which is appropriate for removing cells from specific tissues under certain conditions. A variety of methods have been advanced for evaluating the decellularization process in terms of cell removal efficiency, tissue ultrastructure preservation, toxicity, biocompatibility, biodegradability, and mechanical resistance in order to enhance the efficacy of decellularization methods. Modification techniques improve the characteristics of decellularized scaffolds, making them available for the regeneration of damaged tissues. Moreover, modification of scaffolds makes them appropriate options for drug delivery, disease modeling, and improving stem cells growth and proliferation. However, considering different challenges in the way of decellularization methods and application of decellularized scaffolds, this field is constantly developing and progressively moving forward. This review has outlined recent decellularization and sterilization strategies, evaluation tests for efficient decellularization, materials processing, application, and challenges and future outlooks of decellularization in regenerative medicine and tissue engineering.

9.
Int J Pharm ; 621: 121787, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35508217

RESUMO

In this study, silk fibroin hydrogel is employed as a carrier for vincristine and ultrasound as a method to accelerate the drug release. The Acoustic, deformation, swelling, and diffusion fields are coupled in a multi-physics model to optimize the drug delivery. A transient acoustic structure model and a chemically controlled mechanism are implemented, while a coupled model of deformation and diffusion takes the impact of mechanical forces into account. An evaluation of the model is made through experiments. To monitor the drug release rate over 40 days following injection of silk hydrogel syringes containing vincristine, they were triggered by ultrasound in some selected time intervals. Drug release rates were determined using different power intensities and induction times. Computed simulation results and laboratory experiments revealed that ultrasound could cause a significant improvement in drug release rate, with an increase of up to 10 times over a release without ultrasound stimulation. By increasing the ultrasound power and induction time up to their peak value, the drug release rate rises and drops then. Predictions of the drug release rate by the model were in good agreement with those observed in experiments. This makes the model a valuable tool for potential predictions. Results showed that the ultrasound triggers the increased cell death rates, but the Wilms tumor cells were resistant to higher concentrations of released drugs.


Assuntos
Fibroínas , Tumor de Wilms , Sistemas de Liberação de Medicamentos/métodos , Fibroínas/química , Humanos , Hidrogéis/química , Seda/química , Vincristina , Tumor de Wilms/tratamento farmacológico
10.
J Pediatr Urol ; 18(3): 355-361, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35477666

RESUMO

INTRODUCTION: Female exstrophy-epispadias complex (BEEC) has been considered as a rare malformation of the genito-urinary tract affecting. Combining procedures during the reconstruction of bladder exstrophy-epispadias complex to reduce the number of procedures and improve the outcomes has evoked great interest. OBJECTIVE: we tried to describe the application and results of a single-stage approach for reconstruction of female BEEC during initial reconstruction or following prior failed bladder closure (FBC). STUDY DESIGN: The records of 37 female patients referred for the repair of BEEC without the application of pelvic osteotomies were extracted from an institutionally approved database from September 2002 to August 2018. The mean patient age was 7.24 and 26 patients had a prior FBC. All patients underwent pelvic floor electrical stimulation and toilet training for 1 year after the closure. Complete continence was defined as having the ability to stay dry for more than 3 h without leakage during the day and night. Partial continence has traditionally been defined as retaining urine for 1-3 h or having some stress incontinence. Incontinence was defined as a continence interval of less than 1 h. RESULTS: None of the patients presented bladder prolapse or dehiscence on follow-up; while stricture developed in 2 patients (5.4%). A total of 25 (67.6%) children were dry during the day and night. However, 9 (24.3%) were dry during the day but wet at night; while 3 (8.1%) were totally incontinent. The patients were followed up for a mean of 112.56 months. DISCUSSION: Although earlier reports of this technique seem encouraging, it should be mentioned that postoperative complications are possible and difficult to manage. However, none of our patients were presented with severe postoperative complications in the follow-ups. CONCLUSION: The single-stage technique provides satisfactory outcomes in selected patients with classic bladder exstrophy. The majority of patients attained social dryness without bladder augmentation and intermittent catheterization accompanied with minimum complication rate and best cosmetic results.


Assuntos
Extrofia Vesical , Epispadia , Extrofia Vesical/complicações , Extrofia Vesical/cirurgia , Criança , Epispadia/complicações , Epispadia/cirurgia , Feminino , Humanos , Osteotomia , Complicações Pós-Operatórias/epidemiologia , Procedimentos Cirúrgicos Urológicos/métodos
11.
Urol Case Rep ; 43: 102053, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35311025

RESUMO

Concomitant anterior urethral valve and diverticulum (AUVD) and posterior urethral valve (PUV) is an extremely uncommon congenital anomaly that causes infra-vesical obstruction. We present our experience with one case of concomitant AUVD and PUV as well as the related literature review. Early diagnosis and successful management of these anomalies can improve renal function and prevents recurrent urinary tract infections and subsequent renal failure.

12.
J Biomater Appl ; 36(9): 1527-1539, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35077264

RESUMO

In order to regenerate myocardial tissues with functional characteristics, we need to copy some properties of the myocardium, such as its extracellular matrix and electrical conductivity. In this study, we synthesized nanosheets of Molybdenum disulfide (MoS2), and integrated them into polycaprolactone (PCL) and electrospun on the surface of decellularized human amniotic membrane (DHAM) with the purpose of improving the scaffolds mechanical properties and electrical conductivity. For in vitro studies, we seeded the mouse embryonic cardiac cells, mouse Embryonic Cardiac Cells (mECCs), on the scaffolds and then studied the MoS2 nanocomposites by scanning electron microscopy and Raman spectroscopy. In addition, we characterized the DHAM/PCL and DHAM/PCL-MoS2 by SEM, transmission electron microscopy, water contact angle measurement, electrical conductivity, and tensile test. Besides, we confirmed the scaffolds are biocompatible by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide, MTT assay. Furthermore, by means of SEM images, it was shown that mECCs attached to the DHAM/PCL-MoS2 scaffold have more cell aggregations and elongated morphology. Furthermore, through the Real-Time PCR and immunostaining studies, we found out cardiac genes were maturated and upregulated, and they also included GATA-4, c-TnT, NKX 2.5, and alpha-myosin heavy chain in cells cultured on DHAM/PCL-MoS2 scaffold in comparison to DHAM/PCL and DHAM. Therefore, in terms of cardiac tissue engineering, DHAM nanofibrous scaffolds reinforced by PCL-MoS2 can be suggested as a proper candidate.


Assuntos
Nanofibras , Engenharia Tecidual , Âmnio , Animais , Proliferação de Células , Condutividade Elétrica , Humanos , Camundongos , Molibdênio , Nanofibras/química , Poliésteres/química , Engenharia Tecidual/métodos , Tecidos Suporte/química
13.
J Tissue Eng Regen Med ; 16(2): 91-109, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34808032

RESUMO

Silk worm (Bombyx Mori) protein, have been considered as potential materials for a variety of advanced engineering and biomedical applications for decades. Recently, silkworm silk has gained significant importance in research attention mainly because of its remarkable and exceptional mechanical properties. Silk has already been shown to have unique interactions with cells in tissues through bio-recognition units. The natural silk contains fibroin and sericin and has been used in various tissues of the human body (skin, bone, nerve, and so on). Besides, silk also still has anti-cancer, anti-tyrosinase, anti-coagulant, anti-oxidant, anti-bacterial, and anti-diabetic properties. This article is supposed to describe the diverse biomedical capabilities of B. Mori silk as the appropriate biomaterial among the assorted natural and artificial polymers that are presently accessible, and ideal for usage in regenerative medicine fields.


Assuntos
Bombyx , Fibroínas , Sericinas , Animais , Materiais Biocompatíveis/farmacologia , Medicina Regenerativa
14.
Stem Cell Rev Rep ; 18(2): 752-767, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33742349

RESUMO

Neural tube defects (NTDs) are among the most common congenital defects during neurulation. Spina bifida is a type of NTD that can occur in different forms. Since myelomeningocele (MMC) is the most severe form of spina bifida, finding a satisfactory treatment for MMC is a gold standard for the treatment of spina bifida. The Management of Myelomeningocele Study (MOMS) demonstrated that intrauterine treatment of spina bifida could ameliorate the complications associated with spina bifida and would also reduce the placement of ventriculoperitoneal (VP) shunt by 50%. Recently developed tissue engineering (TE) approaches using scaffolds, stem cells, and growth factors allow treatment of the fetus with minimally invasive methods and promising outcomes. The application of novel patches with appropriate stem cells and growth factors leads to better coverage of the defect with fewer complications. These approaches with less invasive surgical procedures, even in animal models with similar characteristics as the human MMC defect, paves the way for the modern application of less invasive surgical methods. Significantly, the early detection of these problems and applying these approaches can increase the potential efficacy of MMC treatment with fewer complications. However, further studies should be conducted to find the most suitable scaffolds and stem cells, and their application should be evaluated in animal models. This review intends to discuss advanced TE methods for treating MMC and recent successes in increasing the efficacy of the treatment.


Assuntos
Meningomielocele , Disrafismo Espinal , Animais , Feminino , Meningomielocele/complicações , Meningomielocele/diagnóstico , Meningomielocele/terapia , Tubo Neural , Gravidez , Disrafismo Espinal/terapia , Transplante de Células-Tronco , Engenharia Tecidual
15.
J Invest Surg ; 35(4): 737-744, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34139947

RESUMO

PURPOSE: To present the outcomes of revascularized pyeloureterocystoplasty with ureterocele unroofing in end stage bladder patients with duplex system and ureterocele. METHODS: Thirteen patients with obstruction of intrauterine outlet from an ectopic obstructive ureterocele were included. Fourteen units of duplex systems underwent upper pole partial nephrectomy in conjunction with augmentation revascularized pyeloureterocystoplaty and ureterocele unroofing. The anterior and lateral walls of the ureterocele were excised before cystoplasty, and the resultant edges of the posterior wall were sutured to the bladder epithelium. Anastomosis of the upper pole vein and artery to the inferior iliac artery and the common iliac vein was performed. Detubularization of the whole ureter was performed with exception of the intramural ureteric part that kept tubularized for 'jet/turbulent' occurrence. Five patients (control group) underwent pyeloureterocystoplasty without revascularization. Patients underwent several evaluations in long-term follow-up. RESULTS: Patients were all dry by day and night in our long-term follow-up. Urinary incontinence improved in patients with no need for re-augmentation technique. Vesicoureteral reflux subsided in all patients postoperatively except one, who was asymptomatic. After five years, median bladder capacity rose from 128.5 ml to 395 ml and bladder compliance showed significant improvement from 15 ml/cm H2O to 29 ml/cm H2O, in experimental group and remained stable for 24-36 months. Median bladder capacity did not rise significantly in control group. CONCLUSION: Pyeloureterocystoplasty is an efficient choice in this type of patients, which may prevent the recurrence of hypocompliant bladders and prevent ischemia and subsequent fibrosis.


Assuntos
Ureter , Ureterocele , Obstrução do Colo da Bexiga Urinária , Humanos , Lactente , Estudos Retrospectivos , Ureter/cirurgia , Ureterocele/complicações , Ureterocele/cirurgia , Bexiga Urinária/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos
16.
Cell Tissue Bank ; 23(1): 119-128, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33909237

RESUMO

To optimize rabbit kidney decellularization protocol, using sodium dodecyl sulfate (SDS) as a commonly used detergent, a methylene blue based assay was employed for detecting the minimum nontoxic SDS level for future cell seeding. The rabbit kidney tissues were decellularized with the perfusion-based method and underwent several investigations to determine the efficacy of decellularization in preserving the extracellular matrix (ECM) and cell removal. SDS detection was performed by incubating with methylene blue and subsequent extraction with chloroform. MTT (3-(4, 5-dimethylthiazol-2-yr)-2,5-diphenyltetrazolium bromide) assay and SDS release were also evaluated during the entire process. After the first washing cycle, SDS concentration was 0.036, in 500 mL of the washing liquid, which slowly decreased and reached to 0.009 % after at the end of seventh washing cycle. In the 9th cycle, SDS was gradually decreased and reached to 0.003 %. SDS was significantly released after one week of incubation which ceased after ten washing cycles. The results of MTT assay demonstrated that different cells exhibited various sensitivity levels when exposed to serial concentrations of SDS. Human embryonic kidney cells (HEK293) with 0.003 % threshold for cellular toxicity and 87.4 % cell viability were more resistant compared with mesenchymal stem cells with 0.001 % threshold and 85.4 % cell viability. Colorimetric assay with methylene blue is a straightforward and non-invasive method to detect residual SDS present in tissue and can also prevent ECM destruction after several washings for detergent removal from decellularized tissues.


Assuntos
Matriz Extracelular , Rim , Animais , Detergentes , Células HEK293 , Humanos , Perfusão , Coelhos , Dodecilsulfato de Sódio/farmacologia , Engenharia Tecidual , Tecidos Suporte
17.
Biotech Histochem ; 97(3): 207-214, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34107818

RESUMO

We investigated a method for bladder augmentation in rats using a decellularized ureter graft. We used 16 rats divided into two groups of eight. After partial cystectomy, the bladders in group 1 were grafted with a 1 cm2 patch of human decellularized ureter. Rats in group 2 were untreated controls. Biopsies of the graft were taken at 1, 3 and 9 months postoperatively for histological investigation. Total removal of cells and preservation of extracellular matrix (ECM) was confirmed in the decellularized ureter. Histological examination after 1 month revealed few cells at the border of the graft. Three months after the operation, the graft was infiltrated by vessels and smooth muscle and the mucosal lining was complete. All bladder wall components resembled native bladder wall by 9 months after implantation. CD34, CD31, α-smooth muscle actin, S100, cytokeratin AE1/AE3 and vimentin were detected 9 months after the operation. We demonstrated the potential of decellularized biocompatible ureteric grafts for use as a natural collagen scaffold for bladder repair in rats.


Assuntos
Ureter , Bexiga Urinária , Animais , Matriz Extracelular , Músculo Liso , Ratos , Regeneração , Engenharia Tecidual/métodos , Ureter/cirurgia , Bexiga Urinária/patologia , Bexiga Urinária/fisiologia , Bexiga Urinária/cirurgia
18.
Iran J Allergy Asthma Immunol ; 20(5): 635-640, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34664822

RESUMO

Meatal stenosis (MS) is known as one of the most frequent complications of circumcision. In the present study, we aimed to find any possible relationship between MS and allergic disorders. A total of 36 children with a mean±SD age of 5.84±2.03 years were referred with MS and an atopic background even in themselves or in one of their family members (Group A). There were also age-matched controls with a mean±SD age of 5.70±2.17 years who were referred to our center with allergic symptoms and no urinary complaints (Group B, n=17). The RIDA qLine allergy and allergy explorer (ALEX) tests were performed for all patients to find possible allergen sensitization. Laboratory findings revealed that IgE-sensitization to the main food and aeroallergens in Group A (with the chief complaint of MS in whom a mild atopic condition was found during concise medical history taking) were very similar to the control group with no significant difference (except for ryegrass which was higher in the control group). Although total IgE level was considerably higher in group B compared to group A, food sensitization to cow's milk and ß-lactoglobulin was higher in asthmatic patients of group A compared to the controls. It seems that not all patients with MS should be considered as a complication of circumcision and undergo a surgical procedure for correction of the stenosis. Further investigations are required to determine the role of concise medical history taking and proper treatment of the allergic disorder to reduce failed surgical attempts in atopic boys with MS.


Assuntos
Circuncisão Masculina/efeitos adversos , Suscetibilidade a Doenças , Hipersensibilidade Imediata/etiologia , Alérgenos/imunologia , Biomarcadores , Criança , Pré-Escolar , Família , Humanos , Hipersensibilidade Imediata/diagnóstico , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Masculino , Índice de Gravidade de Doença , Avaliação de Sintomas
19.
Int J Pharm ; 609: 121184, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34648880

RESUMO

In this paper, silk fibroin hydrogel is used as a drug carrier for vincristine. To optimize drug delivery, a multi-physics model is proposed that couples the deformation and diffusion fields. We applied inverse analysis and general continuum mechanics to define material parameters and mechanical properties. To examine the mass transport and chemical behavior, an affinity-based diffusion and degradation of a drug-loaded polymer matrix is employed. Some experiments are carried out to examine the capability of the presented model. After preparing the vincristine loaded silk hydrogel syringes, they were injected into PBS and enzyme solutions to monitor the drug release rate for 40 days. Obtained results from the computational simulation and laboratory tests showed that the silk fibroin hydrogel was deswelled after about 40 days in enzyme solution. Degradation led to faster and higher doses of vincristine drug release in comparison to the case of PBS solution. Results revealed that more than 80% of the drug was released in the first 5 days in the enzyme solution, but in PBS solution only 10% of the drug was released during 40 days. The model predictions of deswelling behavior and drug release rate were in good agreement with those of experimental results. Therefore, it can be employed as a reliable tool for further predictions.


Assuntos
Fibroínas , Sistemas de Liberação de Medicamentos , Hidrogéis , Seda , Vincristina
20.
Adv Exp Med Biol ; 1345: 1-6, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34582009

RESUMO

The extracellular matrix (ECM) of mammalian organs and tissues has been applied as a substitute scaffold to simplify the restoration and reconstruction of several tissues. Such scaffolds are prepared in various arrangements including sheets, powders, and hydrogels. One of the more applicable processes is using natural scaffolds, for this purpose discarded tissues or organs are naturally derived by processes that comprised decellularization of following tissues or organs. Protection of the complex structure and 3D (three dimensional) ultrastructure of the ECM is extremely necessary but it is predictable that all protocols of decellularization end in disruption of the architecture and potential loss of surface organization and configuration. Tissue decellularization with conservation of ECM bioactivity and integrity can be improved by providing well-designed protocols regarding the agents and decellularization techniques operated during processing. An overview of the characterization of decellularized scaffolds and the role of reagnets can validate the applied methods' efficacy.


Assuntos
Matriz Extracelular , Engenharia Tecidual , Animais , Hidrogéis , Tecidos Suporte
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