Growth of bone marrow stromal cells on small intestinal submucosa: an alternative cell source for tissue engineered bladder

OBJECTIVE: To assess the potential use of bone marrow stromal cell (BMSC)-seeded biodegradable scaffold for bladder regeneration in a canine model, by characterizing BMSCs and comparing them to bladder smooth muscle cells (SMCs) by immunohistochemistry, growth capability, and contractility. MATERIALS AND METHODS: Bone marrow was taken by direct needle aspiration from the femurs of five beagle dogs for the in vitro study. Mononuclear cells were isolated by Ficoll-Paque density gradient centrifugation and cultivated in medium 199 with 10% fetal bovine serum. BMSCs were characterized by cell proliferation, in vitro contractility, immunohistochemical analysis, and the growth pattern on small intestinal submucosa (SIS) scaffolds compared to bladder SMC cultures from the same dogs. Another six dogs had a hemicystectomy and bladder augmentation with BMSC-seeded (two), bladder cells including urothelial cells plus SMC-seeded SIS (two) and unseeded SIS scaffolds (two). The six dogs were followed for 10 weeks after augmentation. RESULTS: In vitro BMSCs had a significant contractile response to calcium-ionophore, with a mean (sem) 36 (2)%, relative contraction (P < 0.01), which was similar to bladder SMCs but markedly different from fibroblasts. BMSCs also expressed alpha-smooth muscle actin by immunohistochemical staining and Western blotting, but did not express desmin or myosin. In vivo, both BMSC-seeded and bladder cell-seeded SIS grafts had solid smooth-muscle bundle formation throughout the graft. CONCLUSIONS: BMSCs had a similar cell proliferation, histological appearance and contractile phenotype as primary cultured bladder SMCs. SIS supported three-dimensional growth of BMSCs in vitro, and BMSC-seeded SIS scaffold promoted bladder regeneration in a canine model. BMSCs may serve as an alternative cell source in urological tissue engineering.     

Effects of JAK3 inhibition with CP-690,550 on immune cell populations and their functions in nonhuman primate recipients of kidney allografts

BACKGROUND: Janus Kinase (JAK) 3 is a tyrosine kinase essential for proper signal transduction downstream of selected cytokine receptors and for robust T-cell and natural killer cells activation and function. JAK3 inhibition with CP-690,550 prevents acute allograft rejection. To provide further insight into the mechanisms of efficacy, we investigated the immunomodulatory effects of CP-690,550 in vitro and in vivo in nonhuman primates. METHODS: Pharmacodynamic assessments of lymphocyte activation, function, proliferation and phenotype were performed in three settings: in vitro in whole blood isolated from untransplanted cynomolgus monkeys (cynos), in vivo in blood from untransplanted cynos dosed with CP-690,550 for 8 days, and in vivo in blood from transplanted cynos immunosuppressed with CP-690,550. Cell surface activation markers expression, IL-2- enhanced IFN-gamma production, lymphocyte proliferation and immune cell phenotype analyzes were performed with multiparametric flow cytometry. RESULTS: In vitro exposure to CP-690,550 resulted in significant reduction of IL-2-enhanced IFN-gamma production by T-cells (maximum inhibition of 55-63%), T-cell surface expression of CD25 (50% inhibitory concentration (IC50); 0.18 microM) and CD71 (IC50; 1.6 microM), and T-cell proliferative capacities measured by proliferating cell nuclear antigen expression (IC50; 0.87 microM). Similar results were observed in animals dosed with CP-690,550. In addition, transplanted animals displayed significant reduction of NK cell (90% from baseline) and T-cell numbers whereas CD8 effector memory T-cell populations were unaffected. CONCLUSIONS: Potent in vitro and in vivo immunomodulatory effects of the JAK3 inhibitor CP-690,550 likely contribute to its efficacy in the prevention of organ allograft rejection.     

Patient satisfaction and functional status after treatment of infection at the site of a total knee arthroplasty with use of the PROSTALAC articulating spacer

BACKGROUND: Two-stage exchange arthroplasty remains the standard treatment of infection at the site of a total knee arthroplasty. The clinical and functional outcomes associated with the use of an articulating antibiotic spacer for two-stage revision for infection are not well established. We conducted a retrospective study to evaluate the outcomes associated with the use of the PROSTALAC articulating spacer between the first and second stages. METHODS: Fifty-eight patients underwent two-stage revision total knee arthroplasty for infection between January 1997 and December 1999. Of these, fifty-four were alive at the time of follow-up and forty-seven were available for inclusion in the present retrospective study. In all patients, a prosthesis of antibiotic-loaded acrylic cement (the PROSTALAC system) was implanted during the first stage after débridement. The amount of osteolysis that occurred between the stages and the range of motion of the knee joint were measured. After two years of follow-up, outcomes were assessed with use of the WOMAC, Oxford-12, and SF-12 instruments as well as a satisfaction questionnaire. RESULTS: At a minimum of two years (average, forty-one months) after revision arthroplasty, two patients (4%) had had a recurrence of infection. The amount of bone loss was unchanged between stages, and the range of movement of the knee improved from 78.2 degrees before the first stage to 87.1 degrees at two years. The average normalized WOMAC function and pain scores were 68.9 and 77.1, respectively; the average Oxford-12 score was 67.3; the average SF-12 mental and physical scores were 53.7 and 41.2, respectively; and the average satisfaction score was 71.7. CONCLUSION: A revision operation for infection at the site of a total knee replacement with use of an articulating spacer was associated with reasonable function and satisfaction scores. These findings may be related to the articulating features of the PROSTALAC system, which permits full active movement of the knee in the early postoperative period.     

Improvements in knee biomechanics during walking are associated with increased physical activity after total knee arthroplasty

Total knee arthroplasty (TKA) in people with knee osteoarthritis increases knee‐specific and general physical function, but it has not been established if there is a relationship between changes in these elements of functional ability. This study investigated changes and relationships between knee biomechanics during walking, physical activity, and use of time after TKA. Fifteen people awaiting TKA underwent 3D gait analysis before and six months after surgery. Physical activity and use of time were determined in free‐living conditions from a high resolution 24‐h activity recall. After surgery, participants displayed significant improvements in sagittal plane knee biomechanics and improved their physical activity profiles, standing for 105 more minutes (p = 0.001) and performing 64 min more inside chores on average per day (p = 0.008). Changes in sagittal plane knee range of motion (ROM) and peak knee flexion positively correlated with changes in total daily energy expenditure, time spent undertaking moderate to vigorous physical activity, inside chores and passive transport (r = 0.52–0.66, p = 0.005–0.047). Restoration of knee function occurs in parallel and is associated with improvements in physical activity and use of time after TKA. Increased functional knee ROM is required to support improvements in total and context specific physical activity. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1818–1825, 2015.     

A propensity score–matched analysis indicates screening for asymptomatic coronary artery disease does not predict cardiac events in kidney transplant recipients

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Characterization of biochemical recurrence after radical prostatectomy

BACKGROUND: This study sought to characterize the variables that predict postoperative prostate-specific antigen doubling time (PSADT) and biochemical recurrence time (RT) in patients who have failed radical prostatectomy (RP). METHODS: A total of 477 patients underwent RP at our institution for clinically localized prostate cancer. Of these patients, 64 (13.4%) demonstrated evidence of postoperative biochemical failure. PSADT and biochemical RT were calculated for all patients. PSADT and RT were correlated with clinical variables including preoperative PSA level, patient age, race, prostate weight and with pathologic characteristics of the operative specimen using uni- and multivariate analyses. In addition, PSADT and RT were also correlated with each other and with the time to postoperative adjuvant therapy. RESULTS: Median postoperative PSADT for patients who recurred after radical prostatectomy was 9.7 months. Postoperative PSADT was predicted by lymph node involvement (p < 0.001) and Gleason grade (p = 0.06). Rapid PSADT also correlated with institution of postoperative adjuvant therapy (p = 0.003). Median biochemical RT for all patients was 6.7 months. Gleason grade and pathologic stage were found to be predictors of RT (p < 0.002). Postoperative PSADT did not correlate with RT (r = 0.08; p = 0.53). PSADT and RT were not different between Caucasian- versus African-Americans. CONCLUSIONS: These results serve to better characterize our cohort of patients who have evidence of biochemical recurrence after radical prostatectomy. Aggressiveness of recurrent disease (i.e. PSADT) seems to be predicted by lymph node involvement and higher pathologic grade. Furthermore, the lack of correlation of RT and PSADT suggests that early recurrences are not necessarily aggressive tumors: conversely, aggressive recurrences may occur at any point in the postoperative period. This information may aid in the postoperative treatment of recurrent disease and help to better define those patients who are at higher risk for developing clinical recurrence and who would benefit from greater vigilance during the postoperative period.     

Preliminary study of the anatomy of the venous drainage of the intrahepatic and extrahepatic bile ducts and its relevance to the practice of hepatobiliary surgery

Background : Although there have been many studies of the arterial supply of the biliary system, attempts to study the corresponding venous drainage have been few and all have been incomplete. The purpose of the present investigation is to describe the anatomy of the venous drainage of both the intrahepatic and extrahepatic bile ducts and to determine its relevance to hepatobiliary surgery. Methods : The intrahepatic and extrahepatic venous drainage of the bile ducts was investigated in seven specimens by injecting a solution of 10% gelatin coloured with Alcian blue into the portal vein or the superior mesenteric vein to outline the venous drainage. The specimens were dissected under loop magnification and representative drawings were obtained. Results : The surface of the intrahepatic and extrahepatic bile ducts was covered by a fine venous plexus. On the surface of the supraduodenal common hepatic duct and common bile duct the venous plexus drained laterally into marginal veins, usually two in number and known as the 3 o’clock and 9 o’clock marginal veins. Inferiorly the marginal veins and the venous plexus communicated with the pancreaticoduodenal venous plexus, which in its turn drained into the posterosuperior pancreaticoduodenal vein, a branch of the superior mesenteric vein. Superiorly the marginal veins divided into a number of branches. Some branches followed the left and right hepatic ducts into the liver, communicating with the venous plexus and the adjacent branches of the portal vein. Other branches of variable size entered either segment IV or the caudate lobe or process via the hilar venous plexus. A most important finding was that even after dividing the bile duct and all communicating veins at the upper border of the duodenum, the venous plexus and the marginal veins filled normally to the level of transection. This occurred almost certainly by retrograde filling from above. Conclusion : The satisfactory results of end‐to‐end anastomosis in whole liver transplantation depends partly on the presence of adequate venous drainage. This has been amply demonstrated by the injection studies. This would indicate that the poor results of end‐to‐end repair of the bile duct after surgical trauma results from other factors such as poor technique, devascularization of the cut ends due to trauma, and carrying out the anastomosis under tension. After resection of the hilum for cholangiocarcinoma the venous drainage of the left and right hepatic ducts and their branches depends mainly on the communications between the venous plexus on the ducts and the adjacent branches of the portal vein, even at a lobular or sinusoidal level. The satisfactory results obtained after anastomosis of the left and right hepatic ducts or their branches to a Roux loop of jejunum attest to this. This applies also to the transplantation of segments II and III in paediatric patients from related adult donors and in patients receiving split liver transplants. Finally, the venous drainage at the bifurcation of the common hepatic duct has been shown to enter the caudate lobe and segment IV directly. This suggests that a hilar cholangiocarcinoma may metastasize to these segments, and perhaps partly explain the significantly better long‐term results when the caudate lobe and segment IV are resected en bloc with the cholangiocarcinoma as part of modern radical surgery for this condition.     

Mobility and satisfaction with a microprocessor-controlled knee in moderately active amputees: A multi-centric randomized crossover trial

Objective

Microprocessor-controlled knees are generally prescribed and reimbursed for active amputees. Recent studies suggested that this technology could be useful for amputees with moderate activity level. We compared the efficiency of a microprocessor-controlled knee (MPK, Kenevo, Otto Bock) and non-MPKs (NMPKs) in these indications.