Vascularization remains a critical challenge in tissue engineering. The development of vascular networks within densely populated and metabolically functional tissues facilitate transport of nutrients and removal of waste products, thus preserving cellular viability over a long period of time. Despite tremendous progress in fabricating complex tissue constructs in the past few years, approaches for controlled vascularization within hydrogel based engineered tissue constructs have remained limited. Here, we report a three dimensional (3D) micromolding technique utilizing bioprinted agarose template fibers to fabricate microchannel networks with various architectural features within photo cross linkable hydrogel constructs. Using the proposed approach, we were able to successfully embed functional and perfusable microchannels inside methacrylated gelatin (GelMA), star poly (ethylene glycol-co-lactide) acrylate (SPELA), poly (ethylene glycol) dimethacrylate (PEGDMA) and poly (ethylene glycol) diacrylate (PEGDA) hydrogels at different concentrations. In particular, GelMA hydrogels were used as a model to demonstrate the functionality of the fabricated vascular networks in improving mass transport, cellular viability and differentiation within the cell-laden tissue constructs. In addition, successful formation of endothelial monolayers within the fabricated channels was confirmed. Overall, our proposed strategy represents an effective technique for vascularization of hydrogel constructs with useful applications in tissue engineering and organs on a chip.

Pelvic floor failure is a common disorder that can seriously jeopardize a woman's quality of life by causing urinary and fecal incontinence, difficult defecation, and pelvic pain. Multiple congenital and acquired risk factors are associated with pelvic floor failure, including altered collagen metabolism, female sex, vaginal delivery, menopause, and advanced age. A complex variety of fascial and muscular lesions that range from stretching, insertion detachment, denervation atrophy, and combinations of pelvic floor relaxation to pelvic organ prolapse may manifest in a single patient. Thorough preoperative assessment of pelvic floor failure is necessary to reduce the rate of relapse, which is reported to be as high as 30%. Magnetic resonance (MR) imaging of the pelvic floor is a two-step process that includes analysis of anatomic damage on axial fast spin-echo (FSE) T2-weighted images and functional evaluation using sagittal dynamic single-shot T2-weighted sequences during straining and defecation. This article presents high-resolution FSE T2-weighted MR images that permit detailed assessment of anatomic lesions and briefly describes pelvic floor pathophysiology, associated clinical symptoms, and patterns of dysfunction seen with dynamic MR imaging sequences. MR imaging is a powerful tool that enables radiologists to comprehensively evaluate pelvic anatomic and functional abnormalities, thus helping surgeons provide appropriate treatment and avoid repeat operations.

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Objective: To correlate non-restricted diffusion magnetic resonance imaging (MRI) patterns of hepatocellular carcinoma (HCC), with histopathology and clinical outcome.Material and Methods: We retrospectively evaluated pre-treatment MRIs showing non-restricted diffusion HCC lesions (≥1-centimeter), excluding lesions with poor quality/non-available diffusion weighted imaging (DWI). Three radiologists evaluated 37 lesions in 27 patients, for: T1-weighted (T1W)/T2-weighted (T2W) characteristics, arterial enhancement, washout on portal venous/delayed phase, capsular enhancement, intralesional fat component and presence of cirrhosis. Histopathological reports were categorized as: well/moderate/poorly differentiated. Kaplan-Meier survival analysis was calculated for clinical outcome.Results: From a total of 37 lesions, 24 lesions had available pathological grading, which revealed well and moderately differentiated equally (12 lesions each). None of the non-restricted diffusion HCCs were poorly differentiated. Thirty-five of the 37 lesions (94.6%) showed arterial enhancement with washout; 34 lesions (91.9%) were T2W hypo-/isointense, 33 esions (89.2%) were T1W iso-/hyperintense, 19 lesions (51.4%) showed capsular enhancement and 8 lesions (21.6%) had intralesional fat. These findings in the well and moderately differentiated groups were not significantly different (p-value 0.178-1.000). Overall mean-survival was 6.972 years (95% confidence interval (CI); 5.3-8.6). The 1-year, overall survival rate was 83.6% and for 3-years was 67.9%. Mean survival of well and moderately differentiated groups were 6.88 and 7.23 years (95% CI 5.7-8.0 and 4.4-10.1), respectively (p-value=0.319).Conclusion: DWI may help to predict histological grading of HCC and clinical outcome. We found that non-restricted diffusion HCCs were histologically well or moderately differentiated, with no significant difference of imaging findings and survival rates between the two groups. No poorly differentiated lesions were seen in our non-restricted HCC cohort.