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The article presents a case study of female loggerhead sea turtle with a spotted eagle ray (Aetobatus narinari) spine lodged in the left stifle. Endoscopy revealed a second spine entering an intestinal lumen and mentions that the fistulous tract of the left prefemoral fossa excised in the study. The left stifle wound was treated to heal by second intention.

Abstract: Coronary artery disease results in blockages or narrowing of the artery lumen. Drug eluting stents were developed to replace bare metal stents in an effort to combat re-blocking of the lumen. A key element in determining the therapeutic success of a drug eluting stent is an in-depth understanding of the physical factors that affect mass transport of the drug into the arterial wall, over early time periods. The numerical models developed within this study focus on assessing the influence of a host of physical factors that either facilitate or impede therapeutic drug delivery into the arterial wall from the unit cell of an idealised stent. This study demonstrates that model reduction strategies to 2D and 1D can still adequately represent a 3D curved arterial wall and strut polymer coating, respectively, using an idealistic stent geometry. It was shown that the level of strut compression can have a significant impact on therapeutic drug delivery in the arterial wall. [Copyright &y& Elsevier]

Coronary artery disease results in blockages or narrowing of the artery lumen. Drug eluting stents (DES) were developed to replace bare metal stents in an effort to combat re-blocking of the diseased artery following treatment. The numerical models developed within this study focus on representing the changing trends of drug delivery from an idealised DES in an arterial wall with an anisotropic ultra- structure. To reduce the computational burden of solving coupled physics problems, a model reduction strategy was adopted. Particular focus has been placed upon adequately modelling the influence of strut compression as there is a paucity of numerical studies that account for changes in transport properties in compressed regions of the arterial wall due to stent deployment. This study developed an idealised numerical modelling framework to account for the changes in the directionally dependent porosity and tortuosities of the arterial wall as a result of radial strut compression. The results show that depending on the degree of strut compression, trends in therapeutic drug delivery within the arterial wall can be either increased or decreased. The study highlights the importance of incorporating compression into numerical models to better represent transport within the arterial wall and suggests an appropriate numerical modelling framework that could be utilised in more realistic patient specific arterial geometries. [ABSTRACT FROM AUTHOR]

The article presents a case study of a male pygmy sperm whale which was stranded within a tidal pool on Fernandina Beach on the north Florida Atlantic coast and expired soon after discovery. According to necropsy findings, a small intestinal mass which expanded in the intestinal wall and partially obstructed the lumen which led to the malnutrition and the stranding of the whale. The mass was presumptively diagnosed as a leiomyosarcoma through routine histopathology.

The article presents several case studies regarding the growth of cloacal strictures in aquarium-maintained and free-ranging green sea turtles. It informs that coelomic cavity was found to be distended in a female juvenile green sea turtle. It also mentions that another juvenile sea turtle was found to have strictures in intestine and diagnosis in a sea turtle revealed that several factors such as physical activity, obesity and chronic intestinal disease were responsible for the strictures.

The article focuses on the development of a technique for echocardiography in Trichechus manatus latirostris. It states that limited information is available regarding the manatee cardiovascular and cardiopulmonary systems despite of the reported cases of cardiac diseases. It mentions that the echocardiography of manatees reports clear visualization of valves, chambers and measurements of peak aortic flow velocity, and ejection fraction percentage. It states that the echocardiography reveals the incidences of atrioventricular regurgitation and severe right-atrial enlargement.

A quality improvement initiative (QII) was conducted with five community-based health systems' oncology care centers (sites A–E). The QII aimed to increase referrals, genetic counseling (GC), and germline genetic testing (GT) for patients with ovarian cancer (OC) and triple-negative breast cancer (TNBC). QII activities occurred at sites over several years, all concluding by December 2020. Medical records of patients with OC and TNBC were reviewed, and rates of referral, GC, and GT of patients diagnosed during the 2 years before the QII were compared to those diagnosed during the QII. Outcomes were analyzed using descriptive statistics, two-sample t -test, chi-squared/Fisher's exact test, and logistic regression. For patients with OC, improvement was observed in the rate of referral (from 70% to 79%), GC (from 44% to 61%), GT (from 54% to 62%) and decreased time from diagnosis to GC and GT. For patients with TNBC, increased rates of referral (from 90% to 92%), GC (from 68% to 72%) and GT (81% to 86%) were observed. Effective interventions streamlined GC scheduling and standardized referral processes. A multi-year QII increased patient referral and uptake of recommended genetics services across five unique community-based oncology care settings. • A coordinated quality improvement initiative was completed in five community-based health system oncology care centers. • Referral, genetic counseling, and genetic testing improved for patients with ovarian and triple-negative breast cancer. • Average time to completion of genetic testing for patients with ovarian cancer significantly decreased at almost all sites. • The most effective quality improvement interventions standardized genetic counseling referral and delivery processes. [ABSTRACT FROM AUTHOR]

The development of restenosis within the coronary arteries after a stenting procedure has been addressed with the development of the drug eluting stent device. However, in recent times the superiority of the drug eluting stent over bare metal stents has been brought into question. A lack of knowledge regarding the behavior of drug transport from the drug eluting devices contributes to this uncertainty. Questions arise as to whether drug eluting stents deliver sufficient amounts of therapeutic agents into the artery wall to suppress restenosis. Published investigations in this area have focused primarily on trends associated with how variations in stenting conditions affect mass transport behavior. However, experimentally validated numerical models that simulate mass transport within the artery wall are lacking. A novel experimental model was developed to validate computational predictions of species diffusion into a porous medium and an investigation into how stent strut compression influences mass transport was conducted. The study revealed that increased compressive forces on a porous media reduced the ability of species to diffuse through that media, and in relation to drug eluting stents will contribute to a reduction in therapeutic levels of drugs within the wall. [ABSTRACT FROM AUTHOR]

Background: The finite volume solver Fluent (Lebanon, NH, USA) is a computational fluid dynamics software employed to analyse biological mass-transport in the vasculature. A principal consideration for computational modelling of blood-side mass-transport is convection-diffusion discretisation scheme selection. Due to numerous discretisation schemes available when developing a mass-transport numerical model, the results obtained should either be validated against benchmark theoretical solutions or experimentally obtained results. Methods: An idealised aneurysm model was selected for the experimental and computational mass-transport analysis of species concentration due to its welldefined recirculation region within the aneurysmal sac, allowing species concentration to vary slowly with time. The experimental results were obtained from fluid samples extracted from a glass aneurysm model, using the direct spectrophometric concentration measurement technique. The computational analysis was conducted using the four convection-diffusion discretisation schemes available to the Fluent user, including the First-Order Upwind, the Power Law, the Second- Order Upwind and the Quadratic Upstream Interpolation for Convective Kinetics (QUICK) schemes. The fluid has a diffusivity of 3.125 × 10-10 m2/s in water, resulting in a Peclet number of 2,560,000, indicating strongly convection-dominated flow. Results: The discretisation scheme applied to the solution of the convectiondiffusion equation, for blood-side mass-transport within the vasculature, has a significant influence on the resultant species concentration field. The First-Order Upwind and the Power Law schemes produce similar results. The Second-Order Upwind and QUICK schemes also correlate well but differ considerably from the concentration contour plots of the First-Order Upwind and Power Law schemes. The computational results were then compared to the experimental findings. An average error of 140% and 116% was demonstrated between the experimental results and those obtained from the First-Order Upwind and Power Law schemes, respectively. However, both the Second-Order upwind and QUICK schemes accurately predict species concentration under high Peclet number, convection-dominated flow conditions. Conclusion: Convection-diffusion discretisation scheme selection has a strong influence on resultant species concentration fields, as determined by CFD. Furthermore, either the Second-Order or QUICK discretisation schemes should be implemented when numerically modelling convection-dominated mass-transport conditions. Finally, care should be taken not to utilize computationally inexpensive discretisation schemes at the cost of accuracy in resultant species concentration. [ABSTRACT FROM AUTHOR]

Coronary artery disease can be treated by implanting a stent into the blocked region of an artery, thus enabling blood perfusion to distal vessels. Minimally invasive procedures of this nature often result in damage to the arterial tissue culminating in the re-blocking of the vessel. In an effort to alleviate this phenomenon, known as restenosis, drug eluting stents were developed. They are similar in composition to a bare metal stent but encompass a coating with therapeutic agents designed to reduce the overly aggressive healing response that contributes to restenosis. There are many variables that can influence the effectiveness of these therapeutic drugs being transported from the stent coating to and within the artery wall, many of which have been analysed and documented by researchers. However, the physical deformation of the artery substructure due to stent expansion, and its influence on a drugs ability to diffuse evenly within the artery wall have been lacking in published work to date. The paper highlights previous approaches adopted by researchers and proposes the addition of porous artery wall deformation to increase model accuracy. [ABSTRACT FROM AUTHOR]

The in vivo healing process of vascular grafts involves the interaction of many contributing factors. The ability of vascular grafts to provide an environment which allows successful accomplishment of this process is extremely difficult. Poor endothelisation, inflammation, infection, occlusion, thrombosis, hyperplasia and pseudoaneurysms are common issues with synthetic grafts in vivo. Advanced materials composed of decellularised extracellular matrices (ECM) have been shown to promote the healing process via modulation of the host immune response, resistance to bacterial infections, allowing re-innervation and reestablishing homeostasis in the healing region. The physiological balance within the newly developed vascular tissue is maintained via the recreation of correct biorheology and mechanotransduction factors including host immune response, infection control, homing and the attraction of progenitor cells and infiltration by host tissue. Here, we review the progress in this tissue engineering approach, the enhancement potential of ECM materials and future prospects to reach the clinical environment. [ABSTRACT FROM AUTHOR]

Objectives: To assess human in vivo intrarenal pressure (IRP) and peristaltic activity at baseline and after ureteric stent placement, using a narrow calibre pressure guidewire placed retrogradely in the renal pelvis. Patients and Methods: A prospective, multi‐institutional study recruiting consenting patients undergoing ureteroscopy was designed with ethical approval. Prior to ureteroscopy, the urinary bladder was emptied and the COMET™ II pressure guidewire (Boston Scientific) was advanced retrogradely via the ureteric orifice to the renal pelvis. Baseline IRPs were recorded for 1–2 min. At procedure completion, following ureteric stent insertion, IRPs were recorded for another 1–2 min. Statistical analysis of mean baseline IRP, peristaltic waveforms and frequency of peristaltic contractions was performed, thereby analysing the influence of patient variables and ureteric stenting. Results: A total of 100 patients were included. Baseline mean (±SD) IRP was 16.76 (6.4) mmHg in the renal pelvis, with maximum peristaltic IRP peaks reaching a mean (SD) of 25.75 (17.9) mmHg. Peristaltic activity generally occurred in a rhythmic, coordinated fashion, with a mean (SD) interval of 5.63 (3.08) s between peaks. On univariate analysis, higher baseline IRP was observed with male sex, preoperative hydronephrosis, and preoperative ureteric stenting. On linear regression, male sex was no longer statistically significant, whilst the latter two variables remained significant (P = 0.004; P < 0.001). The mean (SD) baseline IRP in the non‐hydronephrotic, unstented cohort was 14.19 (4.39) mmHg. Age, α‐blockers and calcium channel blockers did not significantly influence IRP, and no measured variables influenced peristaltic activity. Immediately after ureteric stent insertion, IRP decreased (mean [SD] 15.18 [5.28] vs 16.76 [6.4] mmHg, P = 0.004), whilst peristaltic activity was maintained. Conclusions: Human in vivo mean (SD) baseline IRP is 14.19 (4.39) mmHg in normal kidneys and increases with both hydronephrosis and preoperative ureteric stenting. Mean (SD) peristaltic peak IRP values of 25.75 (17.9) mmHg are reached in the renal pelvis every 3–7 s and maintained in the early post‐stent period. [ABSTRACT FROM AUTHOR]

Cryopreservation is required to preserve the native properties of tissue for prolonged periods of time. In this study, we evaluate the impact that 4 different cryopreservation protocols have on porcine urethral tissue, to identify a protocol that best preserves the native properties of the tissue. The cryopreservation protocols include storage in cryoprotective agents at −20 °C and −80 °C with a slow, gradual, and fast reduction in temperature. To evaluate the effects of cryopreservation, the tissue is mechanically characterised in uniaxial tension and the mechanical properties, failure mechanics, and tissue dimensions are compared fresh and following cryopreservation. The mechanical response of the tissue is altered following cryopreservation, yet the elastic modulus from the high stress, linear region of the Cauchy stress – stretch curves is unaffected by the freezing process. To further investigate the change in mechanical response following cryopreservation, the stretch at different tensile stress values was evaluated, which revealed that storage at −20 °C is the only protocol that does not significantly alter the mechanical properties of the tissue compared to the fresh samples. Conversely, the ultimate tensile strength and the stretch at failure were relatively unaffected by the freezing process, regardless of the cryopreservation protocol. However, there were alterations to the tissue dimensions following cryopreservation that were significantly different from the fresh samples for the tissue stored at −80 °C. Therefore, any study intent on preserving the mechanical, failure, and geometric properties of urethral tissue during cryopreservation should do so by freezing samples at −20 °C, as storage at −80 °C is shown here to significantly alter the tissue properties. [Display omitted] • The mechanical response of porcine urethral tissue is altered following cryopreservation. • The elastic modulus is unaffected by cryopreservation. • Cryopreservation at −80 °C significantly alters the properties of porcine urethral tissue. • Porcine urethral tissue should be stored at −20 °C as it does not significantly alter its properties. • Cryoprotective agents may cause proteoglycan degradation leading to tissue dehydration. [ABSTRACT FROM AUTHOR]

Background: The aim was to ascertain the impact of irrigation technique on human intrarenal pressure during retrograde intrarenal surgery. Methods: A parallel randomized trial recruited patients across three hospital sites. Patients undergoing retrograde intrarenal surgery for renal stone treatment with an 11/13-Fr ureteral access sheath were allocated randomly to 100 mmHg pressurized-bag (PB) or manual hand-pump (HP) irrigation. The primary outcome was mean procedural intrarenal pressure. Secondary outcomes included maximum intrarenal pressure, variance, visualization, HP force of usage, procedure duration, stone clearance, and clinical outcomes. Live intrarenal pressure monitoring was performed using a COMETTMII pressure guidewire, deployed cystoscopically to the renal pelvis. The operating team was blinded to the intrarenal pressure. Results: Thirty-eight patients were randomized between July and November 2023 (trial closure). The final analysis included 34 patients (PB 16; HP 18). Compared with PB irrigation, HP irrigation resulted in significantly higher mean intrarenal pressure (mean(s.d.) 62.29(27.45) versus 38.16(16.84) mmHg; 95% c.i. for difference in means (MD) 7.97 to 40.29 mmHg; P = 0.005) and maximum intrarenal pressure (192.71(106.23) versus 68.04(24.16) mmHg; 95% c.i. for MD 70.76 to 178.59 mmHg; P < 0.001), along with greater variance in intrarenal pressure (log transformed) (6.23(1.59) versus 4.60(1.30); 95% c.i. for MD 0.62 to 2.66; P = 0.001). Surgeon satisfaction with procedural vision reported on a scale of 10 was higher with PB compared with HP irrigation (mean(s.d.) 8.75(0.58) versus 6.28(1.27); 95% c.i. for MD 1.79 to 3.16; P < 0.001). Subjective HP usage force did not correlate significantly with transmitted intrarenal pressure (Pearson R = −0.15, P = 0.57). One patient (HP arm) developed urosepsis. Conclusion: Manual HP irrigation resulted in higher and more fluctuant intrarenal pressure trace (with inferior visual clarity) than 100-mmHg PB irrigation. Registration number: osf.io/jmg2h (https://osf.io/). In an RCT of patients undergoing retrograde intrarenal surgery with laser lithotripsy in the presence of an 11/13-Fr ureteral access sheath, manual hand-pump irrigation resulted in significantly higher and more fluctuant intrarenal pressure traces than 100-mmHg pressurized-bag irrigation. In addition, surgeon-reported force of hand-pump usage correlated poorly with actual IRP, and surgeons reported preferential clarity of vision with pressurized-bag irrigation. [ABSTRACT FROM AUTHOR]