Histopathological Analysis Of Gangliosides Use In Peripheral Nerve Regeneration After Axonotmesis In Rats

Purpose: To analyze the action of gangliosides in peripheral nerve regeneration in the sciatic nerve of the rat. Methods: The sample was composed of 96 male Wistar rats. The animals were anaesthetized and, after identification of the anaesthesic plane, an incision was made in the posterior region of the thigh, followed by skin and muscle divulsion. The right sciatic nerve was isolated and compressed for 2 minutes. Continuous suture of the skin was performed. The animals were randomly divided into two groups: the experimental group (EG), which received subcutaneous injection of gangliosides, and the control group (CG), which received saline solution (0.9%) to mimic the effects of drug administration. Results: No differences were observed between the experimental and control groups evaluated on the eighth day of observation. At 15 and 30 days the EG showed an decrease in Schwann cell activity and an apparent improvement in fibre organization; at 60 days, there was a slight presence of Schwann cells in the endoneural space and the fibres were organized, indicating nerve regeneration. At 15 and 30 days, the level of cell reaction in the CG had diminished, but there were many cells with cytoplasm in activity and in mitosis; at 60 days, hyperplastic Schwann cells and mitotic activity were again observed, as well as nerve regeneration, but to a lesser extent than in the EG. Conclusion: The administration of exogenous gangliosides seems to improve nerve regeneration.234364371Vasconcelos, B.C., Gay Escoda, C., Vasconcellos, R.J., Neves, R.F., Conduction velocity of the rabbit facial nerve: A noninvasive functional evaluation (2003) Pesqui Odontol Bras, 17, pp. 126-131De Medinacelli, L., Freed, W.J., Wyatt, R.J., An index of the functional condition of rat sciatic nerve based on measurements made from walking tracks (1982) Exp Neur, 77, pp. 6634-6643Nachemson, A.K., Lundborg, G., Myrhage, R., Rank, F., Nerve regeneration and pharmacological suppression of the scar reaction at the suture site (1985) Scand J Plast Reconstr Surg, 19, pp. 255-260Danielsen, N., Varon, S., Characterization of neurotrophic activity in the silicone chamber model for nerve regeneration (1995) J Reconstr Microsurg, 11, pp. 231-235Catan, F.G., Pastorello, A., Siliprandi, R., Savastano, M., Molinari, G., Brain cortex gangliosides and Na+, K+)-ATPase system of the stria vascularis in the guinea pig (1981) Acta Otolaryngol, 92, pp. 433-437Cunha, M.T.R., Silva, A.R., Fenelon, S.B., Comparision of nerve integration after segmentar resection versus epineural burying in crushed rat sciatic nerves (1997) Acta Cir Bras, 4, pp. 221-225Chen, Z.Y., Chai, Y.F., Cao, L., Lu, C.L., He, C., Glial cell line-derived neurotrophic factor enhances axonal regeneration following sciatic nerve transection in adult rats (2001) Brain Res, 2, pp. 272-276Abreu, A.A.N., Wei, T.H., Zumiotti, A.V., Avaliação dos gangliosídeos na regeneração nervosa em ratos. (2002) Rev Bras Ortop, 37, pp. 39-44Neto, J.C., Vasconcelos, B.C., Sobral, A.P., da Silva Jr, V.A., Nogueira, R.V., Clinical and histopathologic study of the use of gangliosides for nerve regeneration in rats after axonotmesis (2007) J Oral Maxillofac Surg, 65, pp. 870-874de Ruiter, G.C., Spinner, R.J., Alaid, A.O., Koch, A.J., Wang, H., Malessy, M.J., Currier, B.L., Windebank, A.J., Two-dimensional digital video ankle motion analysis for assessment of function in the rat sciatic nerve model (2007) J Peripher Nerv Syst, 12, pp. 216-222Schmalbruch, H., Fiber composition of the sciatic nerve (1986) Anat Rec, 215 (1), pp. 71-81Apley, A.G., Teaching techniques and training methods in orthopaedics (1966) Proc R Soc Med, 59 (2), p. 117Kline, D.G., Kim, D., Midha, R., Harsh, C., Tiel, R., Management and results of sciatic nerve injuries: A 24-year experience (1998) J Neurosurg, 89, pp. 13-23Gomes AC, Vasconcelos BC, de Oliveira e Silva ED, da Silva LC. Lingual nerve damage after mandibular third molar surgery: a randomized clinical trial. J Oral Maxillofac Surg. 2005;63:1443-6Horch, H.W., Krüttgen, A., Portbury, S.D., Katz, L.C., Destabilization of cortical dendrites and spines by BDNF (1999) Neuron, 23 (2), pp. 353-364Tos, P., Ronchi, G., Nicolino, S., Audisio, C., Raimondo, S., Fornaro, M., Battiston, B., Geuna, S., Employment of the mouse median nerve model for the experimental assessment of peripheral nerve regeneration (2008) J Neurosci Methods, 169 (1), pp. 119-127Graff-Radford, S.B., Evans, R.W., Lingual nerve injury (2003) Headache, 43, pp. 975-983Montovani, J.C., Prado, R.G., Bacchi, C.E., Experimental surgery of the facial nerve: Evaluation of the intraperitoneal use of exogenous gangliosides (1995) Rev Laryngol Otol Rhinol, 116, pp. 163-167Langone, F., Silva, C.F., Exogenous ganglioside stimulation of axonal regeneration after new transsection and intubation repair (1990) Braz J Med Biol, 23, pp. 823-826Lainetti, R.D., Silva, C.F., Local addition of monosialoganglioside GM1 stimulates peripheral axon regeneration in vivo (1993) Braz J Med Biol Res, 26, pp. 841-845Sobeski, J.K., Kerns, J.M., Safanda, J.F., Shott, S., Gonzalez, M.H., Functional and structural effects of GM-1 ganglioside treatment on peripheral nerve grafting in the rat (2001) Microsurgery, 21, pp. 108-115Amico-Roxas, M., Caruso, A., Trombadore, S., Scifo, R., Scapagnini, U., Gangliosides antinociceptive effects in rodents (1984) Arch Int Pharmacodyn Ther, 272 (1), pp. 103-117(1978) United Nations Educational, Scientific and Culture Organization, , http://portal.unesco.org/en/ev.php-URL_ID=29008&URL_DO=DO_TOPIC&URL_SECTION=201.html, Universal Declaration of Animal Rights, Bruxelles. Available from UR

Cryptococcus neoformans em torres de igrejas da cidade do Rio de Janeiro, RJ, Brasil

Cryptococcosis has been a significant cause of morbidity and mortality in patients with Aids. Many reservoirs of the agent Cryptococcus neoformans have been reported, but the ecology of this yeast must be elucidated in order to establish surveillance programs and to prevent infections. The objective of this study was to evaluate the presence of C. neoformans in Rio de Janeiro City, RJ, Brazil. Ten churches were selected for sampling and detection of the yeast collecting pigeon dropping, air samples from church towers and neighboring areas during one year. The data demonstrated that C. neoformans has been present in every church selected and was present in 37.8% of 219 pigeon dropping samples. As well as, the yeast was isolated from soil, insects, eggs, pigeon nests and feathers. Fifteen air samples (4.9%) were positive. The growth on C.G.B. medium showed that all strains belonged to C. neoformans var. neoformans, with 98.8% of the strains belonging to serotype A.Cryptococcus neoformans é um fungo que ocasiona micose de alta morbidade e mortalidade, especialmente em pacientes com Aids. Muitos reservatórios de C. neoformans têm sido relatados, mas a ecologia desta levedura deve ser ainda elucidada para se estabelecer programas de vigilância e prevenção desta infecção. O objetivo deste estudo foi o de avaliar a presença de C. neoformans no Rio de Janeiro, RJ, Brasil. Dez igrejas foram selecionadas para este estudo, coletando-se fezes de pombo, amostras de ar, das torres das igrejas e de áreas vizinhas, durante um ano. Os resultados revelaram que C. neoformans estava presente em todas as igrejas e em 37,8% das 219 amostras das excretas das aves. Ao mesmo tempo, o fungo foi isolado do solo, insetos, ovos e ninhos de pombos. Quinze (4,9%) do total das amostras de ar foram positivas. O crescimento no meio de CGB revelou que todas as amostras pertenciam a C. neoformans var. neoformans, e 98,8% destas amostras pertenciam ao sorotipo A

B decays and models for CP violation

The decay modes $B$ to $\pi\pi$, $\psi K_S$, $K^- D$, $\pi K$ and $\eta K$ are promising channels to study the unitarity triangle of the CP violating CKM matrix. In this paper I study the consequences of these measurements in the Weinberg model. I show that using the same set of measurements, the following different mechanisms for CP violation can be distinguished: 1) CP is violated in the CKM sector only; 2) CP is violated spontaneously in the Higgs sector only; And 3) CP is violated in both the CKM and Higgs sectors.Comment: 18 pagers, Revtex, Four compressed figures. Some typos in the figure captions are correcte

Kafirin structure and functionality

The structural and functional properties of kafirins are reviewed. Three classes of kafirin: the a, ß and ? forms have been identified at the protein level and one, the d, has been identified only at the gene and transcript levels. All forms show high homology with the equivalent zein proteins. By analogy with the zeins it is believed that the a-kafirins probably have an extended hairpin structure in solution, comprising elements of a-helix, ß-sheet and turns folded back on itself. Kafirins are the most hydrophobic of the prolamins as shown by their solubility, and calculated hydration free energies. The proteins exhibit extensive cross-linking by disulphide bonds and on cooking form indigestible aggregates which are not solubilised by reduction of disulphide bonds. In spite of continuing studies, the reasons for the low digestibility of the protein remain uncertain and there may be several factors involved. Other research has shown that kafirins may have non-food uses and may be used to form films

Climatic effects on sugarcane ripening under the influence of cultivars and crop age

The lack of information about the effects of cultivars, crop age and climate on the sugarcane (Saccharum ssp.) crop yield and quality has been the primary factor impacting the sugar-ethanol sector in Brazil. One of the processes about which we do not have a satisfactory understanding is sugarcane ripening and the effects of cultivars, crop age and climate on that. Sugarcane ripening is the process of sucrose accumulation in stalks, which is heavily influenced by several factors, mainly by climatic conditions such as air temperature and water deficits. Because it is a complex process, studies of the variables involved in sugarcane ripening can provide important information, resulting in a better use of commercial cultivars, bringing advantages to growers, processing units, breeding programs and scientific community. In this review, we discuss the available knowledge of the interaction between climate conditions and sugarcane ripening, under the influence of genotypic characteristics and crop age. In several studies, the main conclusion is that sugarcane ripening depends on a complex combination of climate variables, the genetic potential of cultivars and crop management. Soil moisture and air temperature are the primary variables involved in sugarcane ripening, and their combination stimulates the intensity of the process. In addition, the need for studies integrating the effects of climate on plant physiological processes and on the use of chemical agents to stimulate sugarcane ripening is highlighted

Possible Effects of Noncommutative Geometry on Weak CP Violation and Unitarity Triangles

Possible effects of noncommutative geometry on weak CP violation and unitarity triangles are discussed by taking account of a simple version of the momentum-dependent quark mixing matrix in the noncommutative standard model. In particular, we calculate nine rephasing invariants of CP violation and illustrate the noncommutative CP-violating effect in a couple of charged D-meson decays. We also show how inner angles of the deformed unitarity triangles are related to CP-violating asymmetries in some typical B_d and B_s transitions into CP eigenstates. B-meson factories are expected to help probe or constrain noncommutative geometry at low energies in the near future.Comment: RexTev 16 pages. Modifications made. References added. Accepted for publication in Phys. Rev.

Aspects of Soft and Spontaneous CP Violation

We study four different models for CP violation: the standard (KM) model, the aspon model of spontaneous breaking and two models of soft breaking. In all except the standard model, the strong CP problem is addressed and solved. Testable predictions for the area of the unitarity triangle and for (epsilon'/epsilon)_K are emphasized. The issue of CP violation may well become the first place where the standard model of particle theory is shown definitively to be deficient. There are two reasons for expecting this to happen: (1) the strong CP problem is still not understood in the unadorned standard model and (2) the KM mechanism, although unquestionably present, may not provide the full explanation of epsilon_K and (epsilon'/epsilon)_K.Comment: 24 pages LaTeX including 4 figures. Minor modification to analysis of lower bound for d_n, summarized in new Table I

Weak Phase γ\gamma and Strong Phase δ\delta from CP Averaged B→ππB\to \pi\pi and πK\pi K Decays

Assuming SU(3) symmetry for the strong phases in the four decay modes B\rarrow \pi^-\pi^+, \pi^0 \pi^+, \pi^- K^+, \pi^- \bar{K}^0 and ignoring the relative small electroweak penguin effects in those decays, the weak phase $\gamma$ and the strong phase $\delta$ can be determined in a model independent way by the CP-averaged branching ratios of the four decay modes. It appears that the current experimental data for $B\to \pi\pi$ and $\pi K$ decays prefer a negative value of $\cos\gamma\cos\delta$. By combining with the other constraints from $V_{ub}$, $B^{0}_{d,s}-\bar{B}^{0}_{d,s}$ mixings and indirect CP-violating parameter $\epsilon_K$ within the standard model, two favorable solutions for the phases $\gamma$ and $\delta$ are found to lie in the region: 35^{\circ}\alt\gamma\alt 62^{\circ} and 106^{\circ}\alt \delta \alt 180^{\circ} or 86^{\circ}\alt\gamma\alt 151^{\circ} and 0^{\circ}\alt\delta\alt 75^{\circ} within 1$\sigma$ standard deviation. It is noted that if allowing the standard deviation of the data to be more than 1$\sigma$, the two solutions could approach to one solution with a much larger region for the phases $\gamma$ and $\delta$. Direct CP asymme try $a_{\epsilon''}^{(\pi^- K^+)}$ in B\rarrow \pi^-K^+ decay can be as large as the present experimental upper bound. Direct CP asymmetry $a_{\epsilon''}^{(\pi^+\pi^-)}$ in B\rarrow \pi^-\pi^+ decay can reach up to about 40% at 1$\sigma$ level.Comment: 14 Pages, ReVTeX, 5 figures, one figure (Fig.3) is correcte