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1.
J Tissue Eng Regen Med ; 16(8): 718-731, 2022 08.
Article in English | MEDLINE | ID: mdl-35567775

ABSTRACT

Large animal testing and clinical trials using bioengineered bladder for augmentation have revealed that large grafts fail due to insufficient blood supply. To address this critical issue, an in vivo staged implant strategy was developed and evaluated to create autologous, vascularized bioengineered bladder tissue with potential for clinical translation. Pig bladders were used to create acellular urinary bladder matrices (UBMs), which were implanted on the rectus abdominus muscles of rats and pigs to generate cellular and vascular grafts. Rectus-regenerated bladder grafts (rrBGs) were highly cellularized and contained an abundance of CD31-positive blood vessels, which were shown to be functional by perfusion studies. Muscle patterns within grafts showed increased smooth muscle formation over time and specifically within the detrusor compartment, with no evidence of striated muscle. Large, autologous rrBGs were transplanted to the pig bladder after partial cystectomy and compared to transplantation of control UBMs at 2 weeks and 3 months post-transplant. Functional, ink-perfused blood vessels were found in the central portion of all rrBGs at 2 weeks, while UBM grafts were significantly deteriorated, contracted and lacked central cellularization and vascularization. By 3 months, rrBGs had mature smooth muscle bundles and were morphologically similar to native bladder. This staged implantation technique allows for regeneration and harvest of large bladder grafts that are morphologically similar to native tissue with functional vessels capable of inosculating with host bladder vessels to provide quick perfusion to the central area of the large graft, thereby preventing early ischemia and contraction.


Subject(s)
Muscle, Smooth , Urinary Bladder , Animals , Muscle, Smooth/physiology , Pelvis , Perfusion , Rats , Regeneration/physiology , Swine
2.
Eur Urol Focus ; 4(3): 324-328, 2018 04.
Article in English | MEDLINE | ID: mdl-30146239

ABSTRACT

The use of cannabis use is likely to increase as regulations on its consumption are diminishing throughout the world. Coinciding with an increase in the use of cannabis is an observation that semen quality appears to be declining in developed countries, and couples are delaying conception more often than previous generations. Therefore, it is important to study the effects of cannabis on male reproductive potential in order to better counsel infertile couples and men of reproductive age. In this mini-review, we highlight the known effects of cannabis on clinical markers of male fertility potential and review the role of the endocannabinoid system as it pertains to sex hormone and sperm production, as well as sperm function. Overall, current evidence is contradictory regarding the effects of cannabis on male reproductive hormone production. However, most studies associate cannabis use with lower sperm concentrations, suggesting a negative impact on fertility potential.


Subject(s)
Cannabis/adverse effects , Fertility/drug effects , Reproduction/drug effects , Spermatogenesis/drug effects , Spermatozoa/drug effects , Endocannabinoids/metabolism , Humans , Male , Prevalence , Semen Analysis/trends , Sperm Count/statistics & numerical data , Sperm Motility/drug effects , Spermatozoa/cytology , Substance-Related Disorders/epidemiology
3.
J Infect Chemother ; 22(2): 108-11, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26712583

ABSTRACT

OBJECTIVES: The aim of this study is to characterize the potential differences between male and female patients with acute pyelonephritis (AP) and to predict the severity of AP based on the length of hospital stay. METHODS: We conducted a retrospective medical chart review of 172 consecutive adult patients who were hospitalized in Tsuyama Central Hospital due to AP from January 2007 through June 2012. We analyzed the length of hospital stay by the proportional hazard model. RESULTS: A total of 172 patients were identified who were admitted to our hospital with a diagnosis of AP. Of them, 62% (106/172) were female. Except for urological malignancy, there was no significant difference between men and women in underlying disease. Out of 26 variables, univariate analysis in male showed that only urolithiasis (OR 1.75, p = 0.0294) was significantly associated with longer hospital stay, while septic shock (OR 3.18, P = 0.003), urological malignancy (OR 2.94, P = 0.002), age over 65 (OR 1.66, p = 0.018) and neurogenic bladder (OR 1.92, p = 0.014) were all associated with longer hospital stay in female patients. CONCLUSIONS: This is the first report to identify the risk factors for prolonged hospital stay for the patients who were admitted with AP in the Japanese population. The risk factors causing prolonged hospital stay were totally different between males and females. Reviewing the medical history based on sex gender might enable a clinician to predict the severity of acute pyelonephritis during the initial evaluation.


Subject(s)
Emergency Service, Hospital/statistics & numerical data , Hospitalization/statistics & numerical data , Length of Stay/statistics & numerical data , Pyelonephritis/epidemiology , Pyelonephritis/etiology , Aged , Female , Humans , Male , Retrospective Studies , Risk Factors , Sex Factors , Shock, Septic
4.
Circulation ; 128(11 Suppl 1): S59-68, 2013 Sep 10.
Article in English | MEDLINE | ID: mdl-24030422

ABSTRACT

BACKGROUND: Endothelial progenitor cells (EPCs) possess robust therapeutic angiogenic potential, yet may be limited in the capacity to develop into fully mature vasculature. This problem might be exacerbated by the absence of a neovascular foundation, namely pericytes, with simple EPC injection. We hypothesized that coculturing EPCs with smooth muscle cells (SMCs), components of the surrounding vascular wall, in a cell sheet will mimic the native spatial orientation and interaction between EPCs and SMCs to create a supratherapeutic angiogenic construct in a model of ischemic cardiomyopathy. METHODS AND RESULTS: Primary EPCs and SMCs were isolated from Wistar rats. Confluent SMCs topped with confluent EPCs were spontaneously detached from the Upcell dish to create an SMC-EPC bi-level cell sheet. A rodent ischemic cardiomyopathy model was created by ligating the left anterior descending coronary artery. Rats were then immediately divided into 3 groups: cell-sheet transplantation (n=14), cell injection (n=12), and no treatment (n=13). Cocultured EPCs and SMCs stimulated an abundant release of multiple cytokines in vitro. Increased capillary density and improved blood perfusion in the borderzone elucidated the significant in vivo angiogenic potential of this technology. Most interestingly, however, cell fate-tracking experiments demonstrated that the cell-sheet EPCs and SMCs directly migrated into the myocardium and differentiated into elements of newly formed functional vasculature. The robust angiogenic effect of this cell sheet translated to enhanced ventricular function as demonstrated by echocardiography. CONCLUSIONS: Spatially arranged EPC-SMC bi-level cell-sheet technology facilitated the natural interaction between EPCs and SMCs, thereby creating structurally mature, functional microvasculature in a rodent ischemic cardiomyopathy model, leading to improved myocardial function.


Subject(s)
Endothelium, Vascular/physiology , Myocardial Ischemia/pathology , Myocytes, Smooth Muscle/physiology , Neovascularization, Pathologic/pathology , Stem Cells/physiology , Animals , Coculture Techniques , Endothelium, Vascular/pathology , Female , Humans , Male , Rats , Rats, Wistar , Stem Cells/pathology , Time Factors
5.
Circulation ; 128(11 Suppl 1): S79-86, 2013 Sep 10.
Article in English | MEDLINE | ID: mdl-24030424

ABSTRACT

BACKGROUND: Exogenously delivered chemokines have enabled neovasculogenic myocardial repair in models of ischemic cardiomyopathy; however, these molecules have short half-lives in vivo. In this study, we hypothesized that the sustained delivery of a synthetic analog of stromal cell-derived factor 1-α (engineered stromal cell-derived factor analog [ESA]) induces continuous homing of endothelial progenitor cells and improves left ventricular function in a rat model of myocardial infarction. METHODS AND RESULTS: Our previously designed ESA peptide was synthesized by the addition of a fluorophore tag for tracking. Hyaluronic acid was chemically modified with hydroxyethyl methacrylate to form hydrolytically degradable hydrogels through free-radical-initiated crosslinking. ESA was encapsulated in hyaluronic acid hydrogels during gel formation, and then ESA release, along with gel degradation, was monitored for more than 4 weeks in vitro. Chemotactic properties of the eluted ESA were assessed at multiple time points using rat endothelial progenitor cells in a transwell migration assay. Finally, adult male Wistar rats (n=33) underwent permanent ligation of the left anterior descending (LAD) coronary artery, and 100 µL of saline, hydrogel alone, or hydrogel+25 µg ESA was injected into the borderzone. ESA fluorescence was monitored in animals for more than 4 weeks, after which vasculogenic, geometric, and functional parameters were assessed to determine the therapeutic benefit of each treatment group. ESA release was sustained for 4 weeks in vitro, remained active, and enhanced endothelial progenitor cell chemotaxis. In addition, ESA was detected in the rat heart >3 weeks when delivered within the hydrogels and significantly improved vascularity, ventricular geometry, ejection fraction, cardiac output, and contractility compared with controls. CONCLUSIONS: We have developed a hydrogel delivery system that sustains the release of a bioactive endothelial progenitor cell chemokine during a 4-week period that preserves ventricular function in a rat model of myocardial infarction.


Subject(s)
Chemokine CXCL12/physiology , Endothelial Cells/drug effects , Hydrogels , Myocardial Infarction/drug therapy , Stem Cells/drug effects , Ventricular Function, Left/drug effects , Animals , Cell Movement/drug effects , Cell Movement/physiology , Chemokine CXCL12/administration & dosage , Delayed-Action Preparations , Endothelial Cells/metabolism , Endothelial Cells/physiology , Injections , Male , Myocardial Infarction/metabolism , Myocardial Infarction/pathology , Rats , Rats, Wistar , Stem Cells/metabolism , Stem Cells/physiology , Ventricular Function, Left/physiology
6.
Circulation ; 128(11 Suppl 1): S95-104, 2013 Sep 10.
Article in English | MEDLINE | ID: mdl-24030426

ABSTRACT

BACKGROUND: Cell-mediated angiogenic therapy for ischemic heart disease has had disappointing results. The lack of clinical translatability may be secondary to cell death and systemic dispersion with cell injection. We propose a novel tissue-engineered therapy, whereby extracellular matrix scaffold seeded with endothelial progenitor cells (EPCs) can overcome these limitations using an environment in which the cells can thrive, enabling an insult-free myocardial cell delivery to normalize myocardial biomechanics. METHODS AND RESULTS: EPCs were isolated from the long bones of Wistar rat bone marrow. The cells were cultured for 7 days in media or seeded at a density of 5 × 10(6) cells/cm(2) on a collagen/vitronectin matrix. Seeded EPCs underwent ex vivo modification with stromal cell-derived factor-1α (100 ng/mL) to potentiate angiogenic properties and enhance paracrine qualities before construct formation. Scanning electron microscopy and confocal imaging confirmed EPC-matrix adhesion. In vitro vasculogenic potential was assessed by quantifying EPC cell migration and vascular differentiation. There was a marked increase in vasculogenesis in vitro as measured by angiogenesis assay (8 versus 0 vessels/hpf; P=0.004). The construct was then implanted onto ischemic myocardium in a rat model of acute myocardial infarction. Confocal microscopy demonstrated a significant migration of EPCs from the construct to the myocardium, suggesting a direct angiogenic effect. Myocardial biomechanical properties were uniaxially quantified by elastic modulus at 5% to 20% strain. Myocardial elasticity normalized after implant of our tissue-engineered construct (239 kPa versus normal=193, P=0.1; versus infarct=304 kPa, P=0.01). CONCLUSIONS: We demonstrate restoration and normalization of post-myocardial infarction ventricular biomechanics after therapy with an angiogenic tissue-engineered EPC construct.


Subject(s)
Endothelial Cells/physiology , Endothelial Cells/transplantation , Myocardial Infarction/surgery , Neovascularization, Pathologic/surgery , Tissue Engineering/methods , Animals , Biomechanical Phenomena , Cell Movement/physiology , Cells, Cultured , Male , Myocardial Infarction/pathology , Myocardial Infarction/physiopathology , Neovascularization, Pathologic/pathology , Neovascularization, Pathologic/physiopathology , Random Allocation , Rats , Rats, Wistar
7.
J Thorac Cardiovasc Surg ; 145(1): 278-84, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23244259

ABSTRACT

OBJECTIVE: The biomechanical response to a myocardial infarction consists of ventricular remodeling that leads to dilatation, loss of contractile function, abnormal stress patterns, and ultimately heart failure. We hypothesized that intramyocardial injection of our previously designed pro-angiogenic chemokine, an engineered stromal cell-derived factor-1α analog (ESA), improves mechanical properties of the heart after infarction. METHODS: Male rats (n = 54) underwent either sham surgery (n = 17) with no coronary artery ligation or ligation of the left anterior descending artery (n = 37). The rats in the myocardial infarction group were then randomized to receive either saline (0.1 mL, n = 18) or ESA (6 µg/kg, n = 19) injected into the myocardium at 4 predetermined spots around the border zone. Echocardiograms were performed preoperatively and before the terminal surgery. After 4 weeks, the hearts were explanted and longitudinally sectioned. Uniaxial tensile testing was completed using an Instron 5543 Microtester. Optical strain was evaluated using custom image acquisition software, Digi-Velpo, and analyzed in MATLAB. RESULTS: Compared with the saline control group at 4 weeks, the ESA-injected hearts had a greater ejection fraction (71.8% ± 9.0% vs 55.3% ± 12.6%, P = .0004), smaller end-diastolic left ventricular internal dimension (0.686 ± 0.110 cm vs 0.763 ± 0.160 cm, P = .04), greater cardiac output (36 ± 11.6 mL/min vs 26.9 ± 7.3 mL/min, P = .05), and a lower tensile modulus (251 ± 56 kPa vs 301 ± 81 kPa, P = .04). The tensile modulus for the sham group was 195 ± 56 kPa, indicating ESA injection results in a less stiff ventricle. CONCLUSIONS: Direct injection of ESA alters the biomechanical response to myocardial infarction, improving the mechanical properties in the postinfarct heart.


Subject(s)
Cardiotonic Agents/pharmacology , Chemokine CXCL12/pharmacology , Myocardial Contraction/drug effects , Myocardial Infarction/drug therapy , Myocardium/pathology , Ventricular Function/drug effects , Animals , Biomechanical Phenomena , Cardiotonic Agents/administration & dosage , Cardiotonic Agents/chemical synthesis , Chemokine CXCL12/administration & dosage , Chemokine CXCL12/chemical synthesis , Computer-Aided Design , Disease Models, Animal , Drug Design , Injections , Male , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/pathology , Myocardial Infarction/physiopathology , Rats , Rats, Wistar , Recovery of Function , Stroke Volume/drug effects , Tensile Strength , Time Factors , Ultrasonography , Ventricular Remodeling/drug effects
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