Influence of nanoporous alumina membranes on long-term osteoblast response

A major goal of bone tissue engineering is to design better scaffold configuration and materials to better control osteoblast behavior. Nanoporous architecture has been shown to significantly affect cellular response. In this work, nanoporous alumina membranes were fabricated by a two-step anodization method to investigate bone cell response. Osteoblasts were seeded on nanoporous alumina membranes to investigate both short-term adhesion and proliferation and long-term functionality and matrix production. Cell adhesion and proliferation were characterized using a standard MTT assay and cell counting. The total protein content was measured after cell lysis using the BCA assay. Matrix production was characterized in terms of surface concentrations of calcium and phosphorous, components of bone matrix, using X-ray photoelectron spectroscopy (XPS). The results from nanoporous alumina membranes were compared with those of amorphous alumina, aluminum, commercially available ANOPORE and glass. Results indicate improved osteoblast adhesion and proliferation and increased matrix production after 4 weeks of study.     

Morphometric study of the human fetal heart. I. Arterial segment

This study measured the dimensions of the great arteries of normal human fetal hearts at an early fetal stage (between 13-20 weeks post-fertilization) in 103 fetuses obtained by necropsy. Different segments of the aorta and the pulmonary artery were dissected and their external diameters measured under stereoscopic magnification. All segments showed linear growth during this period of fetal development. Ranges in median values of external diameters associated with the pulmonary artery were: 2.1-4.2 mm for the valve ring; 2.2-4.2 mm for the main pulmonary trunk; 1.2-2.5 mm for the right pulmonary artery; 0.9-2.18 mm for the left pulmonary artery; and 4.0-8.0 mm for the length of the main pulmonary trunk. Similarly, in the aorta, median diameters were: 2.1-4.2 mm for the ascending aorta; 1.92-3.8 mm for the aortic arch; 1.45-3.0 mm for the aortic isthmus; and 1.75 -3.35 mm for the descending aorta. The diameter of the ductus arteriosus ranged between 1.2-2.45 mm. The growth rates of the pulmonary artery and the aorta were similar. The diameter of the ascending aorta was found to be greater than that of the descending aorta and the right pulmonary artery was wider than the left pulmonary artery. In addition, the magnitude of growth in the various aortic segments was different and the ratios obtained between the aortic isthmus and the ascending and descending aortae, ranged between 0.66-0.93. This study provides important morphometric reference information concerning the dimensions and growth of the great arteries of the fetal heart and has clinical application in pediatric cardiac surgery and echocardiography.     

Responses of rat myocardial antioxidant defences and heat shock protein HSP72 induced by 12 and 24-week treadmill training

AIM: The purpose of this study was to determine the effects of both a short (12 weeks) and a long-term (24 weeks) endurance treadmill-training programme on the levels of oxidative stress markers, the activity of the enzymatic antioxidants, and the content of the 72 kDa heat shock protein (HSP72) in rat myocardium. METHODS: Thirty male Wistar rats were randomly assigned to exercise trained (n = 16) and sedentary (n = 14) groups. After 12 week of training, eight rats were killed while the remaining eight continued the training programme until 24 week. RESULTS: Seven sedentary controls were killed together with each trained group. Levels of thiobarbituric acid-reactive substances (TBARS), protein carbonyls, and total and oxidized glutathione (tGSH and GSSG) in myocardial homogenates were unchanged by training irrespective of the protocol duration. However, an increased content of the oxidative stress biomarkers was detected in hearts from both the 24-week trained rats and their sedentary controls when compared with their corresponding 12-week groups. The antioxidant enzymatic activities total and mitochondrial superoxide dismutase (tSOD and mtSOD, respectively), glutathione peroxidase (GPX) and glutathione reductase (GR), remained unchanged after the 12-week training period whereas a significant increase in tSOD and mtSOD activities (18%, P < 0.05) was observed in heart homogenates of 24-week trained animals as compared with their sedentary controls. HSP72 expression levels were not significantly modified after 12 week of training but a threefold increase was detected after 24 week (P < 0.05). CONCLUSION: These results demonstrate that a long-term endurance training (24 weeks) induced discrete increases in antioxidant enzyme activities in rat myocardium and elicited a marked enhancement in HSP72 expression levels. However, a shorter training programme (12 weeks), was not effective in increasing heart antioxidant defences.     

ZnT-1 protects HL-1 cells from simulated ischemia–reperfusion through activation of Ras–ERK signaling

Activation of ERK signaling may promote cardioprotection from ischemia-reperfusion (I/R) injury. ZnT-1, a protein that confers resistance from zinc toxicity, was found to interact with Raf-1 kinase through its C-terminal domain, leading to downstream activation of ERK. In the present study, we evaluated the effects of ZnT-1 in cultured murine cardiomyocytes (HL-1 cells) that were exposed to simulated-I/R. Cellular injury was evaluated by lactate dehydrogenase (LDH) release and by staining for pro-apoptotic caspase activation. Overexpression of ZnT-1 markedly reduced LDH release and caspase activation following I/R. Knockdown of endogenous ZnT-1 augmented the I/R-induced release of LDH and increased caspase activation following I/R. Phospho-ERK levels were significantly increased following I/R in cells overexpressing ZnT-1, while knockdown of ZnT-1 reduced phospho-ERK levels. Pretreatment of cells with the MEK inhibitor PD98059 abolished the protective effect of ZnT-1 following I/R. Accordingly, a truncated form of ZnT-1 lacking the C-terminal domain failed to induce ERK activation and did not protect the cells from I/R injury. In contrast, expression of the C-terminal domain by itself was sufficient to induce ERK activation and I/R protection. Interestingly, the C-terminal of the ZnT-1 did not have protective effect against the toxicity of zinc. In the isolated rat heart, global ischemic injury rapidly increased the endogenous levels of ZnT-1. However, following reperfusion ZnT-1 levels were found to be decreased. Our findings indicate that ZnT-1 may have important role in the ischemic myocardium through its ability to interact with Raf-1 kinase.     

Trophoblast‐Derived Exosomes Mediate Monocyte Recruitment and Differentiation

Citation Atay S, Gercel‐Taylor C, Suttles J, Mor G, Taylor DD. Trophoblast‐derived exosomes mediate monocyte recruitment and differentiation. Am J Reprod Immunol 2011; 65: 65–77 Introduction Trophoblast cells have been demonstrated to regulate monocyte migration and differentiation, leading to pro‐inflammatory profiles. Because trophoblast cells release exosomes with immunoregulatory properties, trophoblast‐derived exosomes are proposed to ‘educate’ monocytes, creating a pro‐inflammatory environment. Method of study Exosomes were isolated from conditioned media of Swan71 cells by ultrafiltration and ultracentrifugation. Exosome‐induced migration was assessed using a two‐chamber system. Cytokine profiles were defined using cytokine arrays, and mRNA levels of affected cytokines were examined by qRT‐PCR and ELISA. Results Within 20 min, 8–10% of monocytes took up labeled exosomes isolated from Swan71 cells. Trophoblast‐derived exosomes increased monocyte migration in a dose‐dependent manner and produced significant increases in production of interleukin (IL)‐1β, IL‐6, Serpin‐E1, granulocyte colony‐stimulating factor, granulocyte/monocyte colony‐stimulating factor, and tumor necrosis factor‐α. Conclusion This study presents the initial demonstration that trophoblast‐derived exosomes are capable of recruiting and ‘educating’ monocytes to produce pro‐inflammatory cytokine/chemokine profiles in a cell‐contact‐independent manner.     

Robotic Vaginal Natural Orifice Transluminal Endoscopic Hysterectomy for Benign Indications

Study ObjectiveThe Hominis surgical system is a novel robot-assisted system, designed specifically for robotic vaginal natural orifice transluminal endoscopic surgery (RvNOTES). We presented our experience of the first 30 RvNOTES hysterectomies assessing the feasibility and safety of this technology.DesignA two-center prospective study.SettingAcademic tertiary referral centers. The ethics committees approved the study in both centers.PatientsThirty women with benign indication for hysterectomy.InterventionRvNOTES hysterectomy performed by the Hominis surgical system.Measurements and Main ResultsThe primary outcome of the study was the rate of conversion to open or conventional laparoscopic approaches. Secondary outcomes included intra- and postoperative adverse events, operative time, estimated blood loss, length of hospital stay, and 6-week follow-up assessment. A total of 15 women were enrolled at each site. The median age was 59 years (range: 37–79) and the median body mass index was 25.4 kg/m² (range: 17.6–40.0). Twenty-four women (80%) had comorbidities. All the procedures were completed successfully without conversion to open abdominal, traditional vaginal, or conventional laparoscopic surgery. No intraoperative complications were observed. Median blood loss and procedure duration were 50 mL (range: 20–400) and 57 minutes (range: 24–88), respectively. Postoperative pain was minimal, with a median visual analog scale of 3 (range: 1–5) for the first 24 hours following surgery. The median hospital stay was 3 days (range: 2–8). According to the treating physicians’ evaluations, the vaginal cuff was fully healed in all patients at the 6-week postoperative follow-up visit.ConclusionsThis is the first publication of robot-assisted vaginal hysterectomy using the Hominis surgical system. The positive results of this study show this new technology to be a safe and effective tool for vaginal natural orifice transluminal endoscopic surgery, enabling surgeons to operate vaginally with the known advantages of robotic modality.     

Superiority of nasal mask pressure over mouth pressure, as a surrogate of diaphragm twitch-related esophageal pressure, in healthy humans

Assessing diaphragm function is clinically and physiologically pertinent. It can rely on the measurement of pressure responses to phrenic stimulation. Combining mouth pressure (Pm) with cervical magnetic stimulation (CMS) is painless and easy to perform, but Pm-CMS poorly reflects esophageal pressure (Pes-CMS) because of poor pressure transmission across the airway. We reasoned that the mouth opening and neck flexion that are associated with the measurement of Pm-CMS would impair upper airway dynamics and further hinder pressure transmission. Therefore, we assessed the CMS-related pressure measured in a nasal mask (Pmask; mouth closed) without neck flexion as a possible surrogate of Pes-CMS, in 14 men and 3 women, age 24.5+/-2.2. Pes-CMS was 15.7+/-4.3 cmH2O, significantly higher than Pm-CMS (13.5+/-5.6 cmH2O, P<0.0001) but not different from Pmask-CMS (15.2+/-4.9 cmH2O). The concordance correlation coefficient was low (0.6808) between Pes-CMS and Pm-CMS. It was higher between Pes-CMS and Pmask-CMS (0.8730). Pm-CMS wrongly classified five subjects as abnormal (<10 cmH2O), versus 1 for Pmask and 5 for Pm (P=0.025). Passing and Bablok regressions found no difference between Pes-CMS and Pmask-CMS, but identified a systematic difference and a proportional error between Pes-CMS and Pm-CMS. We conclude that Pmask-CMS is a better surrogate of Pes-CMS than Pm-CMS.     

Neospora caninum NC-6 Argentina induces fetopathy in both serologically positive and negative experimentally inoculated pregnant dams

Neospora caninum infection is a major cause of abortion in cattle. The objectives of this study were to genetically characterize the N. caninum NC-6 Argentina isolate using a multilocus microsatellite analysis approach and to study its biological behavior by experimental inoculations into seronegative and seropositive pregnant cattle, evaluating the humoral and cellular immune response elicited and the occurrence of transplacental transmission and fetopathy. Pregnant cows (65 days of gestation) seropositive and seronegative to N. caninum were intravenously inoculated with tachyzoites of the NC-6 Argentina N. caninum strain and slaughtered at 108?±?2 days of gestation. Serum samples were analyzed for N. caninum antibodies by indirect fluorescent antibody test. The cellular immune response was analyzed by detection of gamma interferon (γIFN) production in blood cells. Tissue samples from dams, fetuses, and placental cotyledons were processed by histopathological and immunohistochemical techniques and examined for N. caninum DNA by PCR. Positive DNA samples were further analyzed by multilocus microsatellite typing for N. caninum. Inoculated animals had significantly higher N. caninum antibody titers and γIFN production than control animals. One seropositive inoculated cow aborted, one seronegative cow had a non-viable fetus, and the remaining fetuses from the experimentally inoculated dams had histopathologic lesions. The PCR was positive in 3/4 fetuses from seronegative inoculated cows and in 2/3 fetuses from seropositive inoculated cows. Multilocus microsatellite analysis revealed that the N. caninum DNA present in fetuses and placentas had an identical pattern to NC-6 Argentina strain. The NC-6 Argentina strain proved to be able to cross the placenta and to induce fetopathy in both the seropositive and seronegative dams.     

Is 18F-FDG PET/CT useful for imaging and management of patients with suspected occult recurrence of cancer?

Rising serum tumor markers may be associated with negative imaging in the presence of cancer. CT and (18)F-FDG PET may yield incongruent results in the assessment of tumor recurrence. The present study evaluates the incremental role of (18)F-FDG PET/CT for the diagnosis and management of cancer patients with increasing levels of tumor markers as the sole indicator of potential recurrence after initial successful treatment. METHODS: Thirty-six cancer patients with increasing levels of tumor markers during follow-up and negative CT underwent (18)F-FDG PET/CT, which showed 111 sites of increased tracer uptake. PET/CT was compared with PET results on a site-based analysis for characterization of (18)F-FDG foci and on a patient-based analysis for diagnosis of recurrence. The clinical impact of PET/CT on further patient management was evaluated. RESULTS: Thirty patients (83%) had recurrence in 85 malignant sites (77%). For the site-based analysis, PET had a sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of 96%, 50%, 85%, 85%, and 82%, respectively, as compared with the performance indices of PET/CT of 100%, 89%, 97%, 97%, and 100%, respectively. There was a statistically significant difference between the specificity (P < 0.05) and accuracy (P < 0.001) of PET and PET/CT for precise characterization of suspected lesions. For the patient-based analysis, PET had a sensitivity, specificity, and accuracy of 93%, 50%, and 86%, respectively, as compared with PET/CT with values of 93%, 67%, and 89%, respectively (P = not significant). PET/CT was the single modality that directed further management and treatment planning in 12 patients (33%). CONCLUSION: The results of this study indicate that PET/CT may improve the accuracy of occult cancer detection and further lead to management changes in patients with increasing levels of tumor markers as the sole suspicion of recurrent malignancy.