Various evaluation techniques of newly formed bone in porous hydroxyapatite loaded with human bone marrow cells implanted in an extra-osseous site

The purpose of this work was to develop qualitative methods for in situ analysis of bone formation in an osteoconductive hydroxyapatite matrix (ENDOBON), loaded with human bone marrow cells (HBMSC) implanted subcutaneously in athymic mice. Samples were taken before implantation (T0), 1, 2, 4 and 6 weeks after implantation. Bone-biomaterial interaction were investigated on undecalcified sections by histological, cytochemical, immunological and molecular biology methodologies. Histological observations were performed in order to observe inflammatory cells, vessels, newly formed bone, woven and lamellar bone. Enzymohistochemistry was carried out to detect positive tartrate resistant acid phosphatase activity (TRAP+). Immunohistochemistry using antibodies against type I collagen and osteocalcin permitted us to characterize the content of the matrix elaborated within the implant. Moreover, in situ hybridization was carried out to discriminate, the implanted human cells from the murine cells, and to evaluate the function of these human cells in osteogenesis. Results demonstrated an early formation of lamellar bone only in the pores of the studied HAP loaded with HBMSC. This bone contained a matrix showing positive reaction for type I collagen and osteocalcin. In situ hybridization identified some of these cells as human cells. At 6 weeks, examination of histological results showed persistance of lamellar bone in the implants. We only found TRAP+ activity in the materials loaded with human bone marrow cells. Molecular hybridization no longer revealed positive cells for the human DNA probe. All these results indicate that the various evaluation techniques performed on undecalcified sections, permit us to evaluate the response of human bone marrow cells in HAP implanted into mice.     

Associated factors for a hyperechogenic pancreas on endoscopic ultrasound

AIM: To identify the associated risk factors for hyperechogenic pancreas (HP) which may be observed on endoscopic ultrasound (EUS) and to assess the relationship between HP and obesity. METHODS: From January 2007 to December 2007, we prospectively enrolled 524 consecutive adults who were scheduled to undergo EUS. Patients with a history of pancreatic disease or with hepatobiliary or advanced gastrointestinal cancer were excluded. Finally,284 patients were included in the analyses. We further analyzed the ri...     

Contribution of night and day sleep vs. simple passage of time to the consolidation of motor sequence and visuomotor adaptation learning

There is increasing evidence supporting the notion that the contribution of sleep to consolidation of motor skills depends on the nature of the task used in practice. We compared the role of three post-training conditions in the expression of delayed gains on two different motor skill learning tasks: finger tapping sequence learning (FTSL) and visuomotor adaptation (VMA). Subjects in the DaySleep and ImmDaySleep conditions were trained in the morning and at noon, respectively, afforded a 90-min nap early in the afternoon and were re-tested 12 h post-training. In the NightSleep condition, subjects were trained in the evening on either of the two learning paradigms and re-tested 12 h later following sleep, while subjects in the NoSleep condition underwent their training session in the morning and were re-tested 12 h later without any intervening sleep. The results of the FTSL task revealed that post-training sleep (day-time nap or night-time sleep) significantly promoted the expression of delayed gains at 12 h post-training, especially if sleep was afforded immediately after training. In the VMA task, however, there were no significant differences in the gains expressed at 12 h post-training in the three conditions. These findings suggest that “off-line” performance gains reflecting consolidation processes in the FTSL task benefit from sleep, even a short nap, while the simple passage of time is as effective as time in sleep for consolidation of VMA to occur. They also imply that procedural memory consolidation processes differ depending on the nature of task demands. J. Doyon and M. Korman contributed equally.     

Prevention of nonsteroidal inflammatory drug-induced urticaria and/or angioedema

BackgroundUrticaria and/or angioedema (U/AE) are the most frequent and less severe forms of nonallergic hypersensitivity reactions to nonsteroidal anti-inflammatory drugs (NSAIDs). Management of NSAID-induced U/AE includes (1) the avoidance of the culprit drug and of cyclooxygenase (COX) 1 inhibitors, (2) the use of weak COX-2 inhibitors, and/or (3) desensitization to aspirin. Because these possibilities may have drawbacks, we tested the possibility of preventing NSAID-induced U/AE by the administration of antihistamines and/or a combination of antihistamines and leukotriene antagonists.ObjectiveTo test the preventive effect of antihistamines and/or leukotriene antagonists on the development of U/AE in patients with a history of NSAID hypersensitivity confirmed by a positive challenge result.MethodsA single, placebo-controlled, oral challenge using the culprit NSAID was applied to 65 patients with a history of NSAID-induced U/AE. In the case of recurrence of the symptoms, another oral challenge was performed under premedication with antihistamines alone or combined antihistamines and leukotriene antagonists.ResultsA total of 59 of 65 patients (90%) tolerated a normal dose of NSAID, confirming previous data on the poor reproducibility of nonallergic hypersensitivity reactions to NSAIDs on challenge. Of the 6 patients who experienced recurrence of the U/AE on NSAID challenge, antihistamines and combined antihistamines and leukotriene antagonists prevented the hypersensitivity reactions in 2 and 3 of them, respectively. Only 1 patient still developed a moderate NSAID-induced urticaria despite the double premedication.ConclusionTreatment with NSAIDs at normal doses is possible and well tolerated in patients who have experienced NSAID-induced U/AE, which could be prevented by the concomitant use of antihistamines and leukotriene antagonists.     

Hepatoprotective effects of pecan nut shells on ethanol-induced liver damage

The hepatoprotective activity of the aqueous extract of the shells of pecan nut was investigated against ethanol-induced liver damage. This by-product of the food industry is popularly used to treat toxicological diseases. We evaluated the phytochemical properties of pecan shell aqueous extract (AE) and its in vitro and ex vivo antioxidant activity. The AE was found to have a high content of total polyphenols (192.4 ± 1.9 mg GAE/g), condensed tannins (58.4 ± 2.2 mg CE/g), and antioxidant capacity, and it inhibited Fe²⁺-induced lipid peroxidation (LP) in vitro. Rats chronically treated with ethanol (Et) had increased plasmatic transaminases (ALT, AST) and gamma glutamyl transpeptidase (GGT) levels (96%, 59.13% and 465.9%, respectively), which were effectively prevented (87; 41 and 383%) by the extract (1:40, w/v). In liver, ethanol consumption increased the LP (121%) and decreased such antioxidant defenses as glutathione (GSH) (33%) and superoxide dismutase (SOD) (47%) levels, causing genotoxicity in erythrocytes. Treatment with pecan shell AE prevented the development of LP (43%), GSH and SOD depletion (33% and 109%, respectively) and ethanol-induced erythrocyte genotoxicity. Catalase activity in the liver was unchanged by ethanol but was increased by the extract (47% and 73% in AE and AE + Et, respectively). Therefore, pecan shells may be an economic agent to treat liver diseases related to ethanol consumption.     

GM3 synthase deficiency in non-Amish patients

PurposeBiallelic loss-of-function variants in ST3GAL5 cause GM3 synthase deficiency (GM3SD) responsible for Amish infantile epilepsy syndrome. All Amish patients carry the homozygous p.(Arg288Ter) variant arising from a founder effect. To date only 10 patients from 4 non-Amish families have been reported. Thus, the phenotypical spectrum of GM3SD due to other variants and other genetic backgrounds is still poorly known.MethodsWe collected clinical and molecular data from 16 non-Amish patients with pathogenic ST3GAL5 variants resulting in GM3SD.ResultsWe identified 12 families originating from Reunion Island, Ivory Coast, Italy, and Algeria and carrying 6 ST3GAL5 variants, 5 of which were novel. Genealogical investigations and/or haplotype analyses showed that 3 of these variants were founder alleles. Glycosphingolipids quantification in patients’ plasma confirmed the pathogenicity of 4 novel variants. All patients (N = 16), aged 2 to 12 years, had severe to profound intellectual disability, 14 of 16 had a hyperkinetic movement disorder, 11 of 16 had epilepsy and 9 of 16 had microcephaly. Other main features were progressive skin pigmentation anomalies, optic atrophy or pale papillae, and hearing loss.ConclusionThe phenotype of non-Amish patients with GM3SD is similar to the Amish infantile epilepsy syndrome, which suggests that GM3SD is associated with a narrow and severe clinical spectrum.     

Factors associated with survival of very-low-birth-weight infants in a Brazilian fee-paying maternity in the 1990s

This study describes intra-hospital survival rates of very-low-birth-weight infants, as well as factors present at birth associated with survival, during a period of 10 years. This is a Retrospective cohort study performed in a 3rd level nursery at Santa Joana Maternity Hospital, a fee-paying institution in Sao Paulo, Brazil. From January 1991 to December 2000, 963 live-born infants with a birth weight of 500-1499 g, without congenital anomalies, were followed until discharge. Survival was studied according with year of birth, and stratified by birth weight and gestational age. Factors present at birth associated with survival were analyzed by logistic regression. Patient characteristics were: birth weight 500-999 g (38%), gestational ages or=750 g, and gestational age >or=26 weeks.     

After-effects of transcranial direct current stimulation (tDCS) on cortical spreading depression

Abnormal cortical excitability influences susceptibility to cortical spreading depression (CSD) in migraine. Because transcranial direct current stimulation (tDCS) is capable of inducing lasting changes of cortical excitability, we investigated the after-effects of tDCS on the propagation velocity of CSD in the rat. Twenty-five anesthetised rats received either anodal, cathodal or sham tDCS. The stimulation was applied for 20 min at a current strength of 200 microA after the recording of three baseline CSD measurements. Starting 5 min after tDCS, a further three CSDs were elicited and CSD velocity recorded at intervals of 20 min. tDCS and CSD recording was performed under anaesthesia with chloralose and urethane. As compared to the baseline velocity of 3.14 mm/min, anodal tDCS induced a significant increase of propagation velocity during the first post-tDCS recording (3.49 mm/min). In contrast to anodal tDCS, neither cathodal tDCS nor sham tDCS, which consisted of an initial ramped DC stimulation lasting only 20 s, showed a significant effect on CSD propagation velocity. As anodal tDCS is known to induce a lasting increase of cortical excitability in the clinical setting, our results support the notion that CSD propagation velocity reflects cortical excitability. Since cortical excitability and susceptibility to CSD is elevated in migraine patients, anodal tDCS - by increasing cortical excitability - might increase the probability of migraine attack in these patients, even beyond the end of its application.