Bioactive rosette nanotube-hydroxyapatite nanocomposites improve osteoblast functions

Inspired from biological systems, small synthetic organic molecules expressing the hydrogen bonding arrays of the DNA bases guanine and cytosine were prepared, and their self-assembly into rosette nanotubes (RNTs) was investigated. Due to their unique biological, physicochemical, and mechanical properties, RNTs could serve as the next generation of injectable orthopedic materials. In this study, a self-assembling module (termed twin base linkers or TBL) was synthesized, and the corresponding RNTs were used as bioactive components in composites of poly (2-hydroxyethyl methacrylate) (pHEMA) and hydroxyapatite (HA) nanoparticles (termed TBL/HA/pHEMA). The properties of these composites were characterized for solidification time, surface morphology, mechanical properties, and cytocompatibility. The experimental conditions were optimized to achieve solidification within 2-40?min, offering a range of properties for orthopedic applications. Composites with 20?wt% HA nanoparticles had a compressive strength (37.1?MPa) and an ultimate tensile stress (14.7?MPa) similar to that of a natural vertebral disc (5-30?MPa). Specifically, the TBL (0.01?mg/mL)/HA(20?wt%)/pHEMA composites improved long-term functions of osteoblasts (or bone-forming cells) in terms of collagen synthesis, alkaline phosphatase activity, and calcium deposition. Moreover, this composite inhibited fibroblast adhesion, thus decreasing the potential for undesirable fibrous tissue formation. In summary, this in vitro study provided evidence that TBL/HA/pHEMA composites are promising injectable orthopedic implant materials that warrant further mechanistic and in vivo studies.     

Antitumoral activity and osteogenic potential of mesenchymal stem cells expressing the urokinase-type plasminogen antagonist amino-terminal fragment in a murine model of osteolytic tumor

Prostate cancer metastasis to bone results in mixed osteolytic and osteoblastic lesions associated with high morbidity, and there is mounting evidence that the urokinase-type plasminogen system is causatively involved in the progression of prostate cancer. Adult mesenchymal stem cells (MSCs) are promising tools for cell-mediated gene therapy with the advantage of osteogenic potential, a critical issue in the case of osteolytic metastases. In this study, we evaluated the therapeutic use of engineered murine MSCs for in vivo delivery of the urokinase-type plasminogen antagonist amino-terminal fragment (hATF) to impair osteolytic prostate cancer cell progression in bone and to repair bone lesions. Bioluminescence imaging revealed that both primary MSCs and the MSC line C3H10T1/2 (C3) expressing hATF (MSC-hATF) significantly inhibited intratibial PC-3 Luciferase (Luc) growth following coinjection in SCID mice. Furthermore, microcomputed tomography imaging of vascular network clearly demonstrated a significant decrease in tumor-associated angiogenesis and a protection from tumor-induced osteolysis in MSC-hATF-treated mice. Importantly, the osteogenic potential of MSC-hATF cells was unaffected, and an area of new bone formation was evidenced in 60% of animals. Together, these data support the concept of MSC-based therapy of tumor osteolysis disease, indicating that MSCs may combine properties of vehicle for angiostatic agent with osteogenic potential. Disclosure of potential conflicts of interest is found at the end of this article.     

Multivisceral organ failure related to leptospirosis in pregnant patient

Leptospirosis is the most widespread zoonosis in the world. It is caused by pathogenic leptospira infection. This infection is also an uncommon cause of hepatorenal failure. Indeed, hemolysis, elevated liver enzyme levels and low platelet count syndrome, and acute fatty liver of pregnancy are specific to the pregnant state. Leptospirosis is rarely described in pregnancy; it might mimic puerperal sepsis or hepatorenal failure associated with pregnancy induced hypertension. We report a case of leptospirosis presenting as multiple organ failure during third trimester of pregnancy with a good outcome.     

Impact of repeated bouts of eccentric exercise on myogenic gene expression

Evidence indicates that repeated-bouts of eccentric exercise (EE) do not exacerbate the extent of muscle damage indices, as compared to a single-bout. We hypothesized that molecular adaptations, under repeated-bouts of EE, would include suppression of muscle repair inhibitory factors such as myostatin and up-regulation of muscle repair positive regulatory factors such as myogenic regulatory factors (MRFs). Fifteen males were recruited for this study. The exercise group (n = 9) successfully completed six sets of 15 reps of maximum voluntary eccentric contractions, for six consecutive days, using a dynamometer (Multicont-II). Blood and muscle biopsy samples were obtained from each subject 1 week prior to exercise, 2 days post the first training session, and 24 h after the last training session. Gene expression levels were determined using real-time RT-PCR. Blood samples were analyzed for creatine kinase (CK) and lactate-dehydrogenase (LDH) activity. Repeated-bouts of EE induced a large down-regulation of myostatin mRNA (−73%) which persisted throughout the study. The responses of MRFs were mild. At day 3 only myogenin increased significantly (1.9 fold) while MyoD decreased by 45%. Surprisingly, at day 7, despite the presence of muscle damage indices, all MRFs returned to the pre-exercise levels. The results of the present study showed that repeated-bouts of EE, for six consecutive days, dramatically decreased Myostatin mRNA expression but impaired the expression patterns of MRFs such that, with the exception of myogenin that showed a moderate non-sustained increase, MyoD and MYf5 response was minimal. Grants: Funding was provided by the Ministry of Health of the Hungarian Government. Grant number: ETT 388/2003.     

Accuracy of a Cone-Beam CT Virtual Parenchymal Perfusion Algorithm for Liver Cancer Targeting during Intra-arterial Therapy

Purpose

To evaluate accuracy of virtual parenchymal perfusion (VPP) algorithm developed for targeting liver cancer during intra-arterial therapy (IAT) using cone-beam CT guidance.

Metformin Treatment Improves Erectile Function in an Angiotensin II Model of Erectile Dysfunction

IntroductionIncreased angiotensin II (AngII) levels cause hypertension, which is a major risk factor for erectile dysfunction (ED). Studies have demonstrated that increased AngII levels in penile tissue are associated with ED. A recent study showed that metformin treatment restored nitric oxide synthase (NOS) protein expression in penile tissue in obese rats; however, whether metformin treatment can be beneficial and restore erectile function in a model of ED has not yet been established.AimThe goal of this study was to test the hypothesis that AngII induces ED by means of increased corpus cavernosum contraction, and that metformin treatment will reverse ED in AngII-treated rats.MethodsMale Sprague-Dawley rats were implanted with mini-osmotic pumps containing saline or AngII (70 ng/minute, 28 days). Animals were then treated with metformin or vehicle during the last week of AngII infusion.Main Outcome MeasuresIntracavernosal pressure; corpus cavernosum contraction and relaxation; nNOS protein expression; extracellular signal-regulated kinase (ERK1/2), AMP-activated protein kinase (AMPK), and eNOS protein expression and phosphorylation.ResultsAngII-induced ED was accompanied with an increase in corpus cavernosum contractility, decreased nitrergic relaxation, and increased ERK1/2 phosphorylation. Metformin treatment improved erectile function in the AngII-treated rats by reversing the increased contraction and decreased relaxation. Metformin treatment also resulted in an increase in eNOS phosphorylation at ser1177.ConclusionsMetformin treatment increased eNOS phosphorylation and improved erectile function in AngII hypertensive rats by reestablishing normal cavernosal smooth muscle tone. Labazi H, Wynne BM, Tostes R, and Webb RC. Metformin treatment improves erectile function in an angiotensin II model of erectile dysfunction. J Sex Med 2013;10:2154–2164.     

Assessment of phylogenetic structure of Berber-speaking population of Azrou using 15 STRs of Identifiler kit

Allele frequencies for 15 STR autosomal loci of Identifiler kit (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA) in the Moroccan population of Berber-speaking of Azrou, were assessed from a sample of 201 unrelated individuals. Markers D18S51, D2S1338, FGA and D21S11 present the highest power of discrimination (PD) values while D21S11 was the most polymorphic locus in the studied population. The phylogenetic tree established among worldwide populations, shows that Berber-speaking population of Azrou was so close to the Berber-speaking population of Asni but also to the Arab-speaking population of southern Morocco. Nevertheless, a significant distance was observed between populations of Azrou and Bouhria even they share the same dialect (Amazigh) and belong to the same geographical area (Morocco). The 15 STR loci studied appear to be highly discriminating, thus providing a powerful tool for forensic applications, paternity investigation, individual identification and anthropological studies.     

Normal spinal bone marrow in adults: dynamic gadolinium-enhanced MR imaging

PURPOSE: To determine the patterns of dynamic enhancement of normal spinal bone marrow in adults at gadolinium-enhanced magnetic resonance (MR) imaging and the changes that occur with aging. MATERIALS AND METHODS: Dynamic contrast material-enhanced MR imaging of the thoracolumbar spine was performed in 71 patients. The maximum percentage of enhancement (Emax), enhancement slope, and enhancement washout were determined from bone marrow enhancement time curves (ETCs). The bone marrow signal intensity on T1-weighted spin-echo MR images was qualitatively classified into three grade categories. Quantitative ETC values were correlated with patient age and bone marrow fat content grade. Statistical analysis included mean t test comparison, analysis of variance, and regression analysis of the correlations between age and quantitative MR parameters. RESULTS: Emax, slope, and washout varied widely among the patients. Emax values were obtained within 1 minute after contrast material injection and ranged from 0% to 430%. Emax values were significantly higher in patients younger than 40 years than in those aged 40 years or older (P <.001). These values decreased with increasing age in a logarithmic relationship (r = 0.71). Emax values decreased as fat content increased, but some overlap among the fat content grades was noted. Analysis of variance revealed that Emax was significantly related to age (younger than 40 years vs 40 years or older) (P <.001) and fat content grade (P <.001) but not significantly related to sex. CONCLUSION: Dynamic contrast-enhanced MR imaging patterns of normal spinal bone marrow are dependent mainly on patient age and fat content.     

Comparaison de l’Airtraq, du X-Lite et du laryngoscope standard pour la chirurgie thyroïdienne: une étude clinique randomisée

Purpose

To compare the performance of the Airtraq, X-Lite, and direct laryngoscopes for tracheal intubation for elective thyroid surgery.

Methods

In this randomized prospective study, Patients who were ASA (American Society of Anesthesiologists) I or II physical status I or II and patients undergoing thyroid surgery were included in this randomized prospective study. Patients with attributes for difficult intubation criteria were excluded. After induction of anesthesia with fentanyl, propofol, and cisatracurium, patients were randomized into three groups according to the intubating device used: Airtraq laryngoscope (Airtraq), X-Lite video laryngoscope (X-lLite), and direct laryngoscope with a Macintosh blade (Direct). The primary outcome measurement was the time needed for tracheal intubation. Secondary outcomes included intubation difficulty score (IDS), Cormack-Lehane classification, as well as hemodynamic and respiratory effects.

Results

One hundred and five patients were included. Mean (standard deviation) time for intubation was 28.2 (2.1) sec in the Airtraq group vs 36.6 (3.7) sec in the X-Lite group (P < 0.001), and 41.1 (4.4) sec in the Direct group (P < 0.001). Compared with to the direct laryngoscope, the Airtraq provided better visualization of the glottis (P = 0.003) with fewer attempts (P < 0.001) and lower IDS (P < 0.001). The intubation difficulty score was lower with the Airtraq than with the X-Lite (P = 0.003). Patients in the X-Lite and Direct groups showed more hemodynamic variations than those in the Airtraq group. There was only one failed intubation, in the direct group.

Conclusion

In thyroid surgery, the Airtraq and X-Lite laryngoscopes decrease time to intubation when compared with direct laryngoscopy.