Disease-modifying properties of long-term lithium treatment for amnestic mild cognitive impairment: randomised controlled trial

Background Two recent clinical studies support the feasibility of trials to evaluate the disease-modifying properties of lithium in Alzheimer`s disease, although no benefits were obtained from short-term treatment. Aims To evaluate the effect of long-term lithium treatment on cognitive and biological outcomes in people with amnestic mild cognitive impairment (aMCI). Method Forty-five participants with aMCI were randomised to receive lithium (0.25-0.5mmol/l) (n=24) or placebo (n = 21) in a 12-month, double-blind trial. Primary outcome measures were the modification of cognitive and functional test scores, and concentrations of cerebrospinal fluid (CSF) biomarkers (amyloid-beta peptide (A beta(42)), total tau (T-tau), phosphorylated-tau) (P-tau). Trial registration: NCT01055392. Results Lithium treatment was associated with a significant decrease in CSF concentrations of P-tau (P=0.03) and better perform-ance on the cognitive subscale of the Alzheimer`s Disease Assessment Scale and in attention tasks. Overall tolerability of lithium was good and the adherence rate was 91%. Conclusions The present data support the notion that lithium has disease-modifying properties with potential clinical implications in the prevention of Alzheimer`s disease.

THERAPEUTIC ULTRASOUND DID NOT INCREASE THE MECHANICAL PROPERTIES OF FLEXOR TENDONS AFTER THEIR REPAIR

Objective: Experimental study idealized to investigate the mechanical properties of deep flexor tendons of rabbits that underwent the tenotomy followed by tenorrhaphy and early application of therapeutic ultrasound with different intensities, in comparison to tendons submitted to tenorrhaphy only. Material and Method: Forty-four rabbits were divided into four experimental groups according to the ultrasound application. They were all submitted to a section of deep flexor tendon in zone 2 and immobilized with an orthosis maintained throughout the experiment. Group A received ultrasonic treatment with an intensity of 1.4 W/cm(2), group B with 0.6 W/cm(2), both in continuous mode, group C with 0.6 W/cm(2) SATA, in pulsated mode at 50% and group D did not receive any ultrasonic treatment. The ultrasonic frequency employed was 1 MHz. After euthanasia, the tendons were dissected and submitted to the mechanical test of traction and qualitative histological analysis. The evaluated mechanical properties were: maximum force, deformation in maximum force and stiffness. Results: There were no statistically significant differences among the experimental groups. Conclusion: Therapeutic ultrasound did not improve the mechanical properties of the flexor tendons after repair.

Bovine Bone Screws: Metrology and Effects of Chemical Processing and Ethylene Oxide Sterilization on Bone Surface and Mechanical Properties

We assess the effects of chemical processing, ethylene oxide sterilization, and threading on bone surface and mechanical properties of bovine undecalcified bone screws. In addition, we evaluate the possibility of manufacturing bone screws with predefined dimensions. Scanning electronic microscopic images show that chemical processing and ethylene oxide treatment causes collagen fiber amalgamation on the bone surface. Processed screws hold higher ultimate loads under bending and torsion than the in natura bone group, with no change in pull-out strength between groups. Threading significantly reduces deformation and bone strength under torsion. Metrological data demonstrate the possibility of manufacturing bone screws with standardized dimensions.

MECHANICAL PROPERTIES OF GASTROCNEMIUS ELETROSTIMULATED AFTER IMMOBILIZATION

Introduction: Mechanical properties (MP) are clinically applicable tools for healthcare professionals working on the musculoskeletal system. Objectives: The aim of this study was to evaluate two protocols of neuromuscular electric stimulation (NMES) to improve MP regeneration of the myotendinous complex after segment immobilization in female rats. Materials and Methods: Fifty animals were equally distributed into five groups: Control (CG, n=10); Immobilized (IG, n=10); Immobilized and freely remobilized (IFG, n=10); Immobilized and NMES once/day (IEG1, n=10); Immobilized and MNES twice/day (IEG2, n=10). Immobilization was kept for 14 days, and remobilization was subsequently released for 10 days. NMES was applied for 10 days, post-immobilization, every morning for 10 minutes to IEG1 animals and every morning and afternoon (total 20 minutes) to the IEG2 group. After these procedures, the gastrocnemius muscle was submitted to the mechanical traction assay to evaluate stiffness, resilience, load and stretching at maximum limit MPs. Results: Immobilization reduced the MP values concerning load and stiffness (p 0.05). Results for NMES applied twice a day were less satisfactory than the ones obtained with one application or in the remobilized group (p>0.05). Conclusion: It is concluded that the gastrocnemius muscle became structurally better organized through a single NMES application and by remobilization.

Angiotensin II Binding to Angiotensin I-Converting Enzyme Triggers Calcium Signaling

Angiotensin (Ang) I-converting enzyme (ACE) is involved in the control of blood pressure by catalyzing the conversion of Ang I into the vasoconstrictor Ang II and degrading the vasodilator peptide bradykinin. Human ACE also functions as a signal transduction molecule, and the binding of ACE substrates or its inhibitors initiates a series of events. In this study, we examined whether Ang II could bind to ACE generating calcium signaling. Chinese hamster ovary cells transfected with an ACE expression vector reveal that Ang II is able to bind with high affinity to ACE in the absence of the Ang II type 1 and type 2 receptors and to activate intracellular signaling pathways, such as inositol 1,4,5-trisphosphate and calcium. These effects could be blocked by the ACE inhibitor, lisinopril. Calcium mobilization was specific for Ang II, because other ACE substrates or products, namely Ang 1-7, bradykinin, bradykinin 1-5, and N-acetyl-seryl-aspartyl-lysyl-proline, did not trigger this signaling pathway. Moreover, in Tm5, a mouse melanoma cell line endogenously expressing ACE but not Ang II type 1 or type 2 receptors, Ang II increased intracellular calcium and reactive oxygen species. In conclusion, we describe for the first time that Ang II can interact with ACE and evoke calcium and other signaling molecules in cells expressing only ACE. These findings uncover a new mechanism of Ang II action and have implications for the understanding of the renin-Ang system. (Hypertension. 2011;57:965-972.) . Online Data Supplement

Mesenchymal Stem Cell Properties of Periodontal Ligament Cells From Deciduous and Permanent Teeth

Background: Human postnatal stem cells have been identified in periodontal ligaments (PDLs). In this study, the in vitro biologic properties of CD105(+) enriched cell subsets from PDLs harvested from deciduous (DePDL) and permanent (PePDL) teeth are comparatively assessed. Methods: PDL tissue was obtained from 12 teeth (six primary and six permanent) from which CD105(+) CD34(-) CD45(-) cells were isolated by magnetic cell sorting. To identify and quantitatively compare the stem cell markers, DePDL and PePDL cells were assessed for CD166 surface antigen expression by flow cytometry, real-time polymerase chain reaction, and immunostaining for Stro-1 and Oct-4, osteogenic and adipogenic differentiation, and proliferation rate by trypan blue method. Results: Magnetic cell sorting isolated cell populations containing 23.87% (+/- 11.98%) and 11.68% (+/- 6.27%) of CD105(+) expressing cells from PePDL and DePDL, respectively. Flow cytometric analysis demonstrated a higher proportion of CD105(+) cells coexpressing CD166 surface antigen in PePDL, whereas immunostaining and real-time polymerase chain reaction analysis demonstrated that both cell subsets expressed Stro-1 and Oct-4. DePDL-CD105(+) subsets were more proliferative compared to PePDL subsets, and both cell populations showed multipotential capabilities to differentiate in vitro to osteoblast/cementoblast- and adipocyte-like cells. However, a higher expression of adipogenic-related genes was observed in DePDL cells, whereas PePDL-CD105(+) cell subset presented a more homogeneous osteoblast/cementoblast response. Conclusion: These findings demonstrate that highly purified mesenchymal progenitor cell subsets can be obtained from the PDLs of both deciduous and permanent teeth, and further indicate phenotype dissimilarities that may have an impact on their clinical applications. J Periodontol 2010;81:1207-1215.

Angiotensin-converting enzyme inhibition augments the expression of rat elastase-2, an angiotensin II-forming enzyme

Becari C, Teixeira FR, Oliveira EB, Salgado MC. Angiotensin-converting enzyme inhibition augments the expression of rat elastase- 2, an angiotensin II-forming enzyme. Am J Physiol Heart Circ Physiol 301: H565-H570, 2011. First published May 20, 2011; doi:10.1152/ajpheart.00534.2010.-Mounting evidence suggest that tissue levels of angiotensin (ANG) II are maintained in animals submitted to chronic angiotensin-converting enzyme (ACE) inhibitor treatment. We examined the expression levels of transcripts for elastase-2, a chymostatin-sensitive serine protease identified as the alternative pathway for ANG II generation from ANG I in the rat vascular tissue and the relative role of ACE-dependent and -independent pathways in generating ANG II in the rat isolated carotid artery rings of spontaneously hypertensive rats (SHR) and Wistar normotensive rats (WNR) treated with enalapril for 7 days. Enalapril treatment decreased blood pressure of SHR only and resulted in significantly more elastase-2 mRNA expression in carotid artery of both enalapril-treated WNR and SHR. Captopril induced a comparable rightward shift of concentration-response curves to ANG I in vehicle and enalapril-treated rats, although this effect was of lesser magnitude in SHR group. Chymostatin induced a rightward shift of the dose response to ANG I in vehicle-treated and a decrease in maximal effect of 22% in enalapril-treated WNR group. Maximal response induced by ANG I was remarkably reduced by chymostatin in enalapril-treated SHR carotid artery (by 80%) compared with controls (by 23%). Our data show that chronic ACE inhibition was associated with augmented functional role of non-ACE pathway in generating ANG II and increased elastase-2 gene expression, suggesting that this protease may contribute as an alternative pathway for ANG II generation when ACE is inhibited in the rat vascular tissue.

Effect of angiotensin converting enzyme inhibitor enalapril on body weight and composition in young rats

Obesity is considered a worldwide public health problem showing an increased prevalence in developing countries, with urgent need for new and more efficient drugs and therapies. Enalapril, an angiotensin-I converting enzyme inhibitor (ACEi), is classically used in antihypertensive therapies, however, earlier publications have shown that this drug could also have significant impact on body weight in rats as well as in humans, besides reducing blood pressure. The effect of this drug in the white adipose tissue has been neglected for long time, even considering that most components of the renin-angiotensin and kallikrein-kinin system are expressed in this tissue. Furthermore, the adipose tissue is considered today as one of the most important sites for endocrine/inflammatory regulation of appetite and energy output and AngII has been linked to the metabolism in this tissue. Therefore, we analyzed the influence of chronic enalapril treatment in normotensive rats at earlier ages, evaluating body weight, energy homeostasis, lipid profile and serum levels of the hormones leptin and insulin, in the presence of a standard or a palatable hyperlipidic diet regimen for one month. Our results show that enalapril treatment is able to reduce body fat on both diets, without alteration in serum lipid profile. Furthermore, animals receiving enalapril showed reduction in food intake, leptin level and energy intake. In summary, these findings show for the first time that the ACEi enalapril reduces body fat in young normotensive rats and highlights a novel target to treat obesity and associated diseases. (c) 2007 Elsevier B.V. All rights reserved.

Debaryomyces hansenii UFV-1 Intracellular alpha-Galactosidase Characterization and Comparative Studies with the Extracellular Enzyme

Debaryomyces hansenii cells cultivated on galactose produced extracellular and intracellular alpha-galactosidases, which showed 54.5 and 54.8 kDa molecular mass (MALDI-TOF), 60 and 61 kDa (SDS-PAGE) and 5.15 and 4.15 pI values, respectively. The extracellular and intracellular deglycosylated forms presented 36 and 40 kDa molecular mass, with 40 and 34% carbohydrate content, respectively. The N-terminal sequences of the alpha-galactosidases were identical. Intracellular alpha-galactosidase showed smaller thermostability when compared to the extracellular enzyme. D. hansenii UFV-1 extracellular alpha-galactosidase presented higher k(cat) than the intracellular enzyme (7.16 vs 3.29 s(-1), respectively) for the p-nitrophenyl-alpha-D-galactopyranoside substrate. The K(m) for hydrolysis of pNP alpha Gal, melibiose, stachyose, and raffinose were 0.32, 2.12, 10.8, and 32.8 mM, respectively. The intracellular enzyme was acompetitively inhibited by galactose (K(i) = 0.70 mM), and it was inactivated by Cu(II) and Ag(I). Enzyme incubation with soy milk for 6 h at 55 degrees C reduced stachyose and raffinose amounts by 100 and 73%, respectively.

Asymmetric dimethylarginine endogenous inhibition of nitric oxide synthase causes differential vasculature effects

Background: Asymmetric dimethylarginine (ADMA), produced during protein metabolism, is an endogenous inhibitor of nitric oxide synthase, but little is known about its direct vasoactive properties in different arterial beds. Material/Methods: Segments of canine coronary, renal, and femoral arteries were pretreated with increasing concentrations of ADMA, and endothelial function was evaluated in organ chambers. Results: In precontracted canine coronary arteries, the highest concentrations of ADMA inhibited endothelium-dependent relaxation mediated by acetylcholine (n=7), but no concentration of ADMA inhibited receptor-independent relaxation mediated by calcium ionophore (n=7) (P<.001). The effect of ADMA on acetylcholine-mediated relaxation was shown to be competitive inhibition of the nitric oxide synthase pathway, because the addition of L-arginine (10(-3) M), but not D-arginine (101 M), reversed the effect produced by 10(-5) M ADMA. Further, ADMA did not alter endothelium-independent relaxation mediated by sodium nitroprusside (10(-9) to 10(-6) M; n=7). Femoral arteries (n=7) and renal arteries (n=7) were more sensitive to ADMA than were coronary arteries, and they demonstrated significant ADMA inhibition to receptor dependent relaxation induced by acetylcholine (P=.03 and P=.01, respectively) and to receptor-independent relaxation induced by calcium ionophore (P=.02 and P=.01, respectively). Conclusions: Endothelium-dependent relaxation mediated by ADMA is more marked in femoral and renal arteries than in coronary arteries. The response in coronary arteries may be overall protective. Considering these different effects in various artery types, the role of ADMA as a confiable and specific cardiovascular risk factor is questioned.

Evaluation of an Enzyme-Linked Immunosorbent Assay Based on Araraquara Virus Recombinant Nucleocapsid Protein

Laboratory diagnosis of hantavirus cardiopulmonary syndrome (HCPS) in Brazil has been performed mostly by a detection of IgM antibodies to recombinant antigen purified from Sin Nombre virus and Andes Virus (ANDV). Recently, a recombinant nucleocapsid (rN) protein of Argentina virus (ARAV), a Brazilian hantavirus, was Obtained in Escherichia coli. To evaluate ARAV rN as antigen for antibody detection, serum samples from 30 patients front Argentina seropositive for hantavirus were tested. All samples were positive for IgG and IgM by enzyme-linked immunosorbent assay (ELISA) using either ARAV rN or ANDV rN antigens. In Brazil, six of 00 serum samples from patients With suspected HCPS (10%) were positive for IgM by ELISA Using ARAV rN antigen and 7 were positive Using ANDV rN antigen. For results obtained with 90 serum samples analyzed by IgM ELISA with ANDV rN antigen, the sensitivity of the IgM ELISA using ARAV rN antigen was 97.2%,, the specificity was 100%, the positive predictive value was 100% and the negative predictive value was 98.1%. The results show that ARAV rN is a Suitable antigen for diagnosis Of hantavirus infection in Brazil and Argentina.

Multipotent mesenchymal stromal cells obtained from diverse human tissues share functional properties and gene-expression profile with CD146(+) perivascular cells and fibroblasts

Objective. The relationship of multipotent mesenchymal stromal cells (MSC) with pericytes and fibroblasts has not been established thus far, although they share many markers of primitive marrow stromal cells and the osteogenic, adipogenic, and chondrogenic differentiation potentials. Materials and Methods. We compared MSCs from adult or fetal tissues, MSC differentiated in vitro, fibroblasts and cultures of retinal pericytes obtained either by separation with anti-CD146 or adhesion. The characterizations included morphological, immunophenotypic, gene-expression profile, and differentiation potential. Results. Osteogenic, adipocytic, and chondrocytic differentiation was demonstrated for MSC, retinal perivascular cells, and fibroblasts. Cell morphology and the phenotypes defined by 22 markers were very similar. Analysis of the global gene expression obtained by serial analysis of gene expression for 17 libraries and by reverse transcription polymerase chain reaction of 39 selected genes from 31 different cell cultures, revealed similarities among MSC, retinal perivascular cells, and hepatic stellate cells. Despite this overall similarity, there was a heterogeneous expression of genes related to angiogenesis, in MSC derived from veins, artery, perivascular cells, and fibroblasts. Evaluation of typical pericyte and MSC transcripts, such as NG2, CD146, CD271, and CD140B on CD146 selected perivascular cells and MSC by real-time polymerase chain reaction confirm the relationship between these two cell types. Furthermore, the inverse correlation between fibroblast-specific protein-1 and CD146 transcripts observed on pericytes, MSC, and fibroblasts highlight their potential use as markers of this differentiation pathway. Conclusion. Our results indicate that human MSC and pericytes are similar cells located in the wall of the vasculature, where they function as cell sources for repair and tissue maintenance, whereas fibroblasts are more differentiated cells with more restricted differentiation potential. (C) 2008 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc.

The Essential Oil of Eucalyptus tereticornis and its Constituents, alpha- and beta-Pinene, Show Accelerative Properties on Rat Gastrointestinal Transit

The essential oil of Eucalyptus tereticornis (EOET) has pharmacological activities but their effects on the gastrointestinal tract are yet unknown. It possesses alpha- and beta-pinene as minor constituents, isomers largely used as food or drink additives. In this work, we studied their actions on gut motility. After feeding with a liquid test meal, conscious rats received perorally EOET, alpha-, or beta-pinene, and the fractional dye retention was determined. EOET and its constituents decreased the gastric retention. In anesthetized rats, pinenes increased gastric tonus, while enhancing the meal progression in the small intestine of conscious rats. Both alpha- and beta-pinene contracted gastric strips in vitro but relaxed the duodenum. Conversely, EOET relaxed both the gastric and duodenal strips. In conclusion, EOET accelerates the gastric emptying of liquid, and part of its action is attributed to the contrasting effects induced by alpha- and beta-pinene on the gut.