Ectomycorrhizal fungal diversity and community structure associated with cork oak in different landscapes.

Cork oak (Quercus suber L.) forests play an important ecological and economic role. Ectomycorrhizal fungi (ECMF) are key components for the sustainability and functioning of these ecosystems. The community structure and composition of ECMF associated with Q. suber in different landscapes of distinct Mediterranean bioclimate regions have not previously been compared. In this work, soil samples from cork oak forests residing in different bioclimates (arid, semi-arid, sub-humid, and humid) were collected and surveyed for ectomycorrhizal (ECM) root tips. A global analysis performed on 3565 ECM root tips revealed that the ECMF community is highly enriched in Russula, Tomentella, and Cenoccocum, which correspond to the ECMF genera that mainly contribute to community differences. The ECMF communities from the rainiest and the driest cork oak forests were distinct, with soils from the rainiest climates being more heterogeneous than those from the driest climates. The analyses of several abiotic factors on the ECMF communities revealed that bioclimate, precipitation, soil texture, and forest management strongly influenced ECMF structure. Shifts in ECMF with different hyphal exploration types were also detected among forests, with precipitation, forest system, and soil texture being the main drivers controlling their composition. Understanding the effects of environmental factors on the structuring of ECM communities could be the first step for promoting the sustainability of this threatened ecosystem.

A wide diversity of cortical GABAergic interneurons derives from the embryonic preoptic area.

GABA-containing (GABAergic) interneurons comprise a very heterogeneous group of cells that are crucial for cortical function. Different classes of interneurons specialize in targeting specific subcellular domains of excitatory pyramidal cells or other interneurons, which provides cortical circuits with an enormous capability for information processing. As in other regions of the CNS, cortical interneuron diversity is thought to emerge from the genetic specification of different groups of progenitor cells within the subpallium. Most cortical interneurons originate from two main regions, the medial and the caudal ganglionic eminences (MGE and CGE, respectively). In addition, it has been shown that progenitors in the embryonic preoptic area (POA) also produce a small population of cortical GABAergic interneurons. Here, we show that the contribution of the POA to the complement of cortical GABAergic interneurons is larger than previously believed. Using genetic fate mapping and in utero transplantation experiments, we demonstrate that Dbx1-expressing progenitor cells in the POA give rise to a small but highly diverse cohort of cortical interneurons, with some neurochemical and electrophysiological characteristics that were previously attributed to MGE- or CGE-derived interneurons. There are, however, some features that seem to distinguish POA-derived interneurons from MGE- or CGE-derived cells, such as their preferential laminar location. These results indicate that the mechanisms controlling the specification of different classes of cortical interneurons might be more complex than previously expected. Together with earlier findings, our results also suggest that the POA generates nearly 10% of the GABAergic interneurons in the cerebral cortex of the mouse.

Defining a Standardized Information Model for Multi-Source Representation of Breast Cancer Data.

This work aims to define a standardized information model for representation of multiple data sources in breast cancer. A set of data elements has been identified using ICHOM Breast Cancer as the minimum data set and adapting it to the needs of Hospital Universitario 12 de Octubre. With this, an information model has been defined according to ISO 13606 and SNOMED CT standards.

Enhanced HLA-DR expression on T-lymphocytes from patients in early stages of non-surgical sepsis.

INTRODUCTION: Early detection of sepsis is a critical step to improve patient's survival and cellular markers effective diagnosis tools. The aim of this work was to evaluate HLA-DR expression on peripheral T-lymphocytes (CD3+), a marker associate to T-cell activation, as an early sepsis detection tool. PATIENTS AND METHODS: A cross-sectional study was conducted in twenty-six patients with confirmed sepsis by blood culture, eighteen healthy individuals and four patients with systemic inflammatory response syndrome. The analysis of the HLA-DR expression was carried by flow cytometry. RESULTS: The patients with confirmed sepsis had significantly higher percentage of CD3+/HLA-DR+ lymphocytes compared with both, patients with SIRS (20.37±9.42 vs. 8.7±2.9; p<0.005) and healthy individuals (20.37±9.42 vs. 6.58±3.89; p<0.005). Moreover, the average amount of HLA-DR expressed was higher when caused by gram-positive than by gram-negative bacterias (216.61±131.35 vs. 135.05±31.82; p=0.041). A ROC curve analysis showed the utility of HLA-DR expression on T-cells to identify patients with sepsis. DISCUSSION: Our results suggest that surface expression of HLA-DR on T-lymphocytes could be an early marker for the presence of sepsis in non-surgical septic patients.

Endothelial Effect of Statin Therapy at a High Dose Versus Low Dose Associated with Ezetimibe.

BACKGROUND: The effect of statins on the endothelial function in humans remains under discussion. Particularly, it is still unclear if the improvement in endothelial function is due to a reduction in LDL-cholesterol or to an arterial pleiotropic effect. OBJECTIVE: To test the hypothesis that modulation of the endothelial function promoted by statins is primarily mediated by the degree of reduction in LDL-cholesterol, independent of the dose of statin administered. METHODS: Randomized clinical trial with two groups of lipid-lowering treatment (16 patients/each) and one placebo group (14 patients). The two active groups were designed to promote a similar degree of reduction in LDL-cholesterol: the first used statin at a high dose (80 mg, simvastatin 80 group) and the second used statin at a low dose (10 mg) associated with ezetimibe (10 mg, simvastatin 10/ezetimibe group) to optimize the hypolipidemic effect. The endothelial function was assessed by flow-mediated vasodilation (FMV) before and 8 weeks after treatment. RESULTS: The decrease in LDL-cholesterol was similar between the groups simvastatin 80 and simvastatin 10/ezetimibe (27% ± 31% and 30% ± 29%, respectively, p = 0.75). The simvastatin 80 group presented an increase in FMV from 8.4% ± 4.3% at baseline to 11% ± 4.2% after 8 weeks (p = 0.02). Similarly, the group simvastatin 10/ezetimibe showed improvement in FMV from 7.3% ± 3.9% to 12% ± 4.4% (p = 0.001). The placebo group showed no variation in LDL-cholesterol level or endothelial function. CONCLUSION: The improvement in endothelial function with statin seems to depend more on a reduction in LDL-cholesterol levels, independent of the dose of statin administered, than on pleiotropic mechanisms.

Molecular cloning and protein expression of Duchenne muscular dystrophy gene products in porcine retina.

Due to the difference between rodent and human retinal circuitry, we characterize a new animal model of retinal perturbation in neurotransmission in Duchenne Muscular Dystrophy (DMD) patients. We investigated the expression and localization of dystrophin proteins and dystrophin associated proteins in porcine retina by reverse transcription polymerase chain reaction, Western blot analysis and immunohistochemistry. Homologues of human DMD gene products and alternative spliced isoforms of Dp71 were identified. We observed that dystrophins were expressed in the outer plexiform layer, around blood vessels and at the inner limiting membrane as previously described in human and mouse retinae. Moreover, by double immunostaining we showed that beta-dystroglycan co-localizes with dystrophin in the outer plexiform layer whereas alpha1-syntrophin labeling differs from that for dystrophins. Using confocal laser microscopy we observed that dystrophins labeling co-localizes with pre- and post-synaptic cell markers in the outer plexiform layer. We suggest that porcine retina constitutes a good model to study the role of dystrophins in retinal neurotransmission and should be used to investigate the physiological roles of dystrophins in signal transduction.

Depolarizing effect of GABA in horizontal cells of the rabbit retina.

Gamma-amino butyric acid (GABA) has been characterized as an inhibitory neurotransmitter acting through chloride mediated channels in the adult nervous system. Using gramicidin-perforated patch clamp recordings from horizontal cells dissociated from the retinas of adult rabbits, we found that GABA is able to induce cell depolarization. Ionic currents induced by GABA in dissociated horizontal cells showed a reversal potential close to -30 mV. This value is more positive than the resting potential of these cells (ca. -70 mV). Therefore, according to the Nernst equation, the intracellular chloride concentration in horizontal cells was estimated to be of 44 mM. The depolarizing effect of GABA at the dendrites of horizontal cells may serve to shape the center-surround organization of the receptive fields in retinal cells, thereby securing the shape discrimination of visual input.

Depolarizing effect of GABA in rod bipolar cells of the mouse retina.

Gamma-amino butyric acid (GABA) has been characterized as inhibitory neurotransmitter through chloride mediated channels in the adult nervous system. However, using gramicidin perforated patch-clamp recordings from rod bipolar cells dissociated from retinas of adult mice, we find that GABA is capable of inducing cell depolarization. Currents mediated by GABA(A) and GABA(C) receptors were further isolated by the use of GABA receptor specific blockers. In rod bipolar cells dissociated from the mouse retina, activation of GABA(A) receptors located at the cell dendrites induces ionic currents which show a reversal potential of -33 mV. However, local activation of GABA(C) receptors located at the axon terminal induces ionic currents with a reversal potential of -60 mV. According to Nernst equation, the dendrites of rod bipolar cells of the mouse retina would have a high intracellular chloride concentration ([Cl(-)](i)) and there must be an intracellular gradient in [Cl(-)](i), being the [Cl(-)](i) more elevated in the dendrites than in the axon terminal. The depolarizing effect of GABA at the dendrites of rod bipolar cells may contribute to the lateral interaction in the mammalian retina, thereby enhancing visual discrimination of stimuli input.

Functional modifications in rod bipolar cells in a mouse model of retinitis pigmentosa.

The rd mouse has been widely used as an animal model of retinitis pigmentosa. In this model, a mutation of rod-specific phosphodiesterase leads to a loss of rods during the early period of postnatal life. Morphological modifications at the level of the outer plexiform layer have been shown (Proc. Nat. Acad. Sci. USA 97 (2000) 11020) in bipolar and horizontal cells. However, very little is known about the functional changes suffered by these cells postsynaptic to the degenerated rods. In the present work we have studied the neurotransmitter-induced currents in rod bipolar cells from the rd mouse retina. Currents induced by glutamate and GABA were studied by the patch clamp-whole cell technique, on rod bipolar cells enzymatically dissociated from the rd mouse retina. Data from rd animals were compared with non-dystrophic NMRI mice. GABA (30-100 micro M) and glutamate (100 micro M) were applied from a puff pipette in the near proximity of rod bipolar cell dendrites, clamped at physiological membrane potentials, and their evoked currents were studied. In rod bipolar cells from non-dystrophic mouse, puff application of glutamate induced an outward current. This current was increased twofold in absence of extracellular calcium (nominally 0 calcium). In rod bipolar cells from adult rd mouse, currents induced by glutamate were absent. Two types of GABA mediated currents were isolated in rod bipolar cells both in control and rd mouse retinas. The currents mediated by GABA(C) receptors were observed exclusively at the axon terminal, while the currents mediated by the GABA(A) receptors were observed upon GABA application to the bipolar cell dendrites. The currents mediated by GABA(A) receptors in rod bipolar cells from rd mouse were larger than those from control animals. We conclude that after the degeneration of rod photoreceptors in rd mouse, rod bipolar cells lost their glutamate (rod-neurotransmitter) input while they increase their response to GABA (horizontal cell-neurotransmitter). In our opinion, this work describes for the first time the changes in neurotransmitter sensitivity that affect rod bipolar cells after photoreceptor degeneration of the mouse retina.

Composición química y calidad proteica de fideos complementados con harina de Porphyra columbina / Chemical composition and protein quality of pasta complemented with Porphyra columbina

La harina de trigo es un alimento no balanceado, debido al bajo valor biológico de su proteína, originado por la deficiencia de lisina. Para mejorar las propiedades nutricionales de la pasta de trigo, se utilizan distintas fuentes con alto contenido y calidad de proteína. Las algas son un recurso abundante, económico y atractivo para utilizar como ingrediente en alimentos. Entre las macroalgas rojas comestibles, Porphyra columbina es una de las más importantes de la Patagonia Argentina. El objetivo de este trabajo fue comparar la composición química y la calidad proteica de fideos elaborados con harina de Triticum durum (FC) y fideos complementados al 30% en la fase sólida con harina de Porphyra columbina (F30). La composición centesimal se determinó por métodos oficiales de la AOAC. La determinación cuantitativa de aminoácidos se llevó a cabo mediante el método propuesto por Alaiz et al. (23). La separación de los aminoácidos se realizó mediante HPLC. Los resultados de composición química para FC y F30, expresados en g cada 100 g de pasta seca comestible, fueron respectivamente: humedad 7,9 ± 0,4 y 8,1 ± 0,2; cenizas 1,0 ± 0,1 y 1,7 ± 0,1; grasas 5,6 ± 0,2 y 4,7 ± 0,1; proteínas 15,8 ± 0,1 y 17,7 ± 0,1; fibra dietaria total 7,7 ± 0,3 y 19,8 ± 0,2 y carbohidratos 62,0 y 47,9. Los cálculos del puntaje químico, teniendo en cuenta las necesidades del preescolar, revelaron un valor de 55% y 94% para FC y F30, respectivamente. En FC la lisina se evidenció como el aminoácido limitante, mientras que en F30 el limitante fue el triptofano(AU).

The wheat pasta is an unbalanced food, due to the low biological value of its protein, caused by the deficiency of lysine. To improve the nutritional properties of wheat pasta, different sources with high protein content and quality are used. Seaweed is an abundant, economical and attractive resource to use as an ingredient in food. Among red edible macroalgae, Porphyra columbina is one of the most important ones in Argentine Patagonia. The objective of this work was to compare the chemical composition and protein quality of pasta made with Triticum durum flour (FC) and pasta supplemented at 30% in the solid phase with Porphyra columbina flour (F30). The centesimal composition was determined by AOAC official methods. The quantitative determination of amino acids was carried out by the method proposed by Alaiz, et al.(23). The separation of amino acids was carried out through HPLC. The chemical composition results for FC and F30, expressed in g per 100 g of edible dry pasta, were: water 7,9 ± 0,4 and 8,1 ± 0,2; ash 1,0 ± 0,1 and 1,7 ± 0,1; fat 5,6 ± 0,2 and 4,7 ± 0,1; protein 15,8 ± 0,1 and 17,7 ± 0,1; total dietary fiber 7,7 ± 0,3 and 19,8 ± 0,2 and carbohydrates 62,0 and 47,9, respectively. The chemical score, taking into account the needs of pre-schoolers, revealed a value of 55% and 94% for FC and F30, respectively. In FC, lysine was found to be the limiting amino acid, whereas in F30, the limiting factor was tryptophan(AU).

Síndrome de Apnea-Hipoapnea del Sueño (SAHOS) como factor de riesgo peri-operatorio: Relevancia clínica y rol del anestesiólogo en la evaluación pre-quirúrgica / Preoperative evaluation of Obstructve sleep apnea (OSA) as a perioperative risk factor

Obstructive sleep apnea (OSA) is a common sleep related breathing disorder in the general population and polysomnography is the gold standard method for the diagnosis. It has a higher prevalence among elective surgical patients, however it remains as an underdiagnosed condition that is associated with significant morbidity and mortality in the perioperative setting. The aim of this review article is to highlight the role of the anesthesiologist in the preoperative assessment, based on current available evidence and suggest some strategies to identify patients at higher risk.

El síndrome de apnea obstructive es un desorden frecuente de la respiración durante el sueño. La polisomnografía es su método diagnostico. Si bien tiene una alta prevalencia en pacientes quirúrgicos electivos, están subdiagnósticados y su presencia a morbimortalidad perioperatoria. El objetivo de esta revisión es validar el rol del anestesiólogo en la evaluación preoperatoria y sugerir estrate- gias para identificar a pacientes de alto riesgo.

Endothelial Effect of Statin Therapy at a High Dose Versus Low Dose Associated with Ezetimibe / Efeito Endotelial da Terapia com Estatina em Alta Dose versus Baixa Dose Associada à Ezetimiba

Abstract Background: The effect of statins on the endothelial function in humans remains under discussion. Particularly, it is still unclear if the improvement in endothelial function is due to a reduction in LDL-cholesterol or to an arterial pleiotropic effect. Objective: To test the hypothesis that modulation of the endothelial function promoted by statins is primarily mediated by the degree of reduction in LDL-cholesterol, independent of the dose of statin administered. Methods: Randomized clinical trial with two groups of lipid-lowering treatment (16 patients/each) and one placebo group (14 patients). The two active groups were designed to promote a similar degree of reduction in LDL-cholesterol: the first used statin at a high dose (80 mg, simvastatin 80 group) and the second used statin at a low dose (10 mg) associated with ezetimibe (10 mg, simvastatin 10/ezetimibe group) to optimize the hypolipidemic effect. The endothelial function was assessed by flow-mediated vasodilation (FMV) before and 8 weeks after treatment. Results: The decrease in LDL-cholesterol was similar between the groups simvastatin 80 and simvastatin 10/ezetimibe (27% ± 31% and 30% ± 29%, respectively, p = 0.75). The simvastatin 80 group presented an increase in FMV from 8.4% ± 4.3% at baseline to 11% ± 4.2% after 8 weeks (p = 0.02). Similarly, the group simvastatin 10/ezetimibe showed improvement in FMV from 7.3% ± 3.9% to 12% ± 4.4% (p = 0.001). The placebo group showed no variation in LDL-cholesterol level or endothelial function. Conclusion: The improvement in endothelial function with statin seems to depend more on a reduction in LDL-cholesterol levels, independent of the dose of statin administered, than on pleiotropic mechanisms.

Resumo Fundamento: O efeito das estatinas na função endotelial em seres humanos permanece em discussão. Particularmente, ainda carece resposta se a melhora na função endotelial deve-se à redução do LDL-colesterol ou a um efeito pleiotrópico arterial. Objetivo: Testar a hipótese de que a modulação da função endotelial promovida por estatinas é prioritariamente mediada pelo grau de redução do LDL-colesterol, independente da dose de estatina utilizada. Métodos: Ensaio clínico randomizado com dois grupos de tratamento hipolipemiante (16 pacientes/cada) e um grupo placebo (14 pacientes). Os dois grupos ativos foram desenhados para promover graus semelhantes de redução de LDL-colesterol: o primeiro utilizou estatina em alta dose (80 mg, grupo sinvastatina 80) e o segundo em baixa dose (10 mg) associada a ezetimiba (10 mg, grupo sinvastatina 10/ezetimiba) para otimizar o efeito hipolipemiante. A função endotelial foi analisada pela vasodilatação mediada por fluxo (VMF) antes e após 8 semanas de tratamento. Resultados: A redução no LDL-colesterol foi semelhante entre os grupos sinvastatina 80 e sinvastatina 10/ezetimiba (27% ± 31% e 30% ± 29%, respectivamente, p = 0,75). O grupo sinvastatina 80 apresentou incremento da VMF de 8,4% ± 4,3% no basal para 11% ± 4,2% após 8 semanas (p = 0,02). Da mesma forma, o grupo sinvastatina 10/ezetimiba apresentou melhora da VMF de 7,3% ± 3,9% para 12% ± 4,4% (p = 0,001). O grupo placebo não apresentou variação no nível de LDL-colesterol ou da função endotelial. Conclusão: A melhora da função endotelial com uso de estatina parece depender mais da redução do LDL-colesterol, independente da dose de estatina utilizada, do que de mecanismos pleiotrópicos.

Acurácia e precisão do método ultrassonográfico manual de aferição da espessura mediointimal carotídea tendo como referência o método semiautomático / Accuracy and precision of ultrasound manual measurement of carotid intima-media thickness having semiautomatic method as reference / Exactitud y Precisión del Método Ecográfico Manual de Medición del Espesor Mediointimal Carotideo, teniendo como referencia el Método Semiautomático

Fundamento: A tecnologia semiautomática de detecção de bordas para aferição da Espessura Mediointimal Carotídea (EMIC), além de oferecer menor tempo de exame, apresenta mínima variabilidade das medidas.Objetivo: Testar a acurácia e a reprodutibilidade do método manual, tendo o semiautomático como referência.Métodos: Selecionadas mulheres do Ambulatório de Obesidade para aferição da EMIC. A avaliação do método manual (EMICmanual) foi realizada tomando-se a medida máxima do método semiautomático (EMICsamax) como referência, sendo utilizados teste de correlação de Pearson, grau de concordância e variabilidades inter e intraobservador nos dois modelos, além do teste de Kappa. Resultados: Na amostra de 59 participantes, houve forte correlação da medida de EMICmanual com EMICsamax (r = 0,84, p < 0,0001) e boa concordância entre ambos os métodos, dada a pequena média das diferenças de 0,06 ± 0,04 mm das medidas, com limites de concordância no nível 95 por cento entre -0,02 a 0,14 mm. A concordância na definição de aterosclerose subclínica foi moderada, de 53 por cento , (Kappa de 52 por cento p < 0,0001). Observou-se forte correlação com os métodos manual e semiautomático, entre as medidas intra e interobservador e boa reprodutibilidade intraobservador das medidas de EMICmanual, com diferença média de 0,04 ± 0,03 mm e limites de concordância no nível 95 por cento entre -0,02 a 0,10 mm, semelhantemente às medidas de EMICsamax, que se repetiu na reprodutibilidade interobservador. Conclusão: O método manual de aferição da EMIC pôde ser validado como método alternativo ao semiautomático.

Background: The semiautomated ultrasound border detection technology for measurement carotid intima-media thickness (CIMT) provides shorter time of exam and minimal variability measures.Objective: To evaluate the accuracy of the manual method, taking the semiautomated as reference and the reproducibility of the methods.Methods: Data were obtained from women of Ambulatory of Obesity directed to CIMT measurements determination. The evaluation of the manual method (manualCIMT) was performed, taking the maximum thickness of the semiautomated method (samaxCIMT) as reference. The statistical analyses used Pearson correlation, degree of agreement and inter and intraobserver variabilities in the two models and Kappa test.Results: In the sample of 59 women, there was a strong correlation of manualCIMT with samaxCIMT (r = 0.84, p <0.0001) and a good agreement between both methods, given the small mean difference of measures (0.06 ± 0.04 mm), with limits of agreement at 95 percent level between -0.02 to 0.14 mm. The agreement on the definition of subclinical atherosclerosis was moderate, 53 percent (kappa 52 percent, p <0.0001). The correlation between manual and semiautomated measurements in intra and inter-observer analyses was strong. The intraobserver reproducibility for manualCIMT measures was good and similar of interobserver, with a mean difference of 0.04 ± 0.03 mm and limits of agreement at 95 percent level between -0.02 to 0.10 mm. For EMICsamáx similar result was observed. Conclusion: The Manual method of measuring carotid intima-media thickness could be validated as na alternative to semi-automated.

Justificación: La tecnología semiautomática de detección de bordes para medición del Espesor Mediointimal Carotideo (EMIC), además de ofrecer un menor tiempo de examen, presenta mínima variabilidad de las medidas. Objetivo: Poner a prueba la exactitud y la reproducibilidad del método manual, tomando el semiautomático como referencia. Métodos: Se han seleccionadas mujeres en la Clínica de Obesidad para medición de EMIC. La evaluación del método manual (EMICmanual) ha sido realizada tomándose la medida máxima del método semiautomático (EMICsamax) como referencia, ya que se utiliza prueba de correlación de Pearson, grado de concordancia y variabilidades inter e intraobservador en los dos modelos, además de la prueba de Kappa. Resultados: En la muestra de 59 participante, hubo fuerte correlación de la medida de EMICmanual con EMICsamax (r = 0,84, p < 0,0001) y una buena concordancia entre los dos métodos, dado el pequeño promedio de las diferencias de 0,06 ± 0,04 mm de las medidas, con límites de concordancia al nivel del 95% entre -0,02 a 0,14 mm. La concordancia en la definición de aterosclerosis subclínica ha sido moderada, del 53%, (Kappa del 52% p < 0,0001). Se ha observado una fuerte correlación con los métodos manual y semiautomático, entre las medidas intra e interobservador y buena reproducibilidad intraobservador de las medidas de EMICmanual, con diferencia media de 0,04 ± 0,03 mm y límites de concordancia al nivel del 95% entre -0,02 a 0,10 mm, de forma similar a las medidas de EMICsamax, que se repitió en la reproducibilidad inter-observador. Conclusión: El método manual de medición de EMIC puede evaluarse como método alternativo al semiautomático

Periodontal conditions in subjects following orthodontic therapy. A preliminary study.

The present study evaluated the periodontal conditions in dental students after appliance removal (mean period 7.16 +/- 3.5 years) compared with an untreated control group. Twenty-five subjects in the treated group (16 females and 9 males: 23.0 +/- 2.04 years) and 29 in a control group (15 females and 14 males: 23.99 +/- 2.46 years) underwent a periodontal examination: visible plaque index (VPI), gingival bleeding index (GBI), bleeding on probing (BOP), periodontal probing depth (PPD), and clinical attachment loss (CAL) of canines, premolars, and banded first molars and unbanded second molars. Statistical analysis was performed using a Mann-Whitney test, a Student's t-test, and Tukey's analysis of variance. The level of significance was set at 5 per cent. The median percentage of positive sites for the treated and control groups for VPI (1.25 +/- 2.37 and 1.25 +/- 5.45), GBI (0.95 +/- 1.81 and 1.23 +/- 2.14), and BOP (0.83 +/- 6.45 and 0.83 +/- 3.43) did not differ between groups. Mean PPD values were 1.33 +/- 0.19 and 1.34 +/- 0.14 for the treated and 1.40 +/- 0.24 and 1.39 +/- 0.25 for the control group. No intra- or intergroup differences were observed. For the control group, the smallest PPD was at the canines followed by premolars and molars. PPD was less for premolars than molars but similar to the canines in the treated group. No differences in CAL were observed between the examined teeth in the control group. For the treated group, the canines showed lower CAL values than the first molars. The results indicate that the use of orthodontic appliances is not necessarily related to a worsening of periodontal conditions.

Voltage-gated channels and calcium homeostasis in mammalian rod photoreceptors.

Recent reports on rod photoreceptor neuroprotection by Ca2+ channel blockers have pointed out the need to assess the effect of these blockers on mammalian rods. However, in mammals, rod electrophysiological characterization has been hampered by the small size of these photoreceptors, which were instead extensively studied in nonmammalian vertebrates. To further characterize ionic conductances and to assess the pharmacology of Ca2+ channels in mammalian rods, freshly dissociated pig rod photoreceptors were recorded with the whole cell patch-clamp technique. Rod cells expressed 1) a hyperpolarization-activated inward-rectifying conductance (I(h)) sensitive to external Cs+; 2) a sustained outward K+ current (I(K)) sensitive to tetraethylammonium; 3) a sustained voltage-gated Ca2+ current (I(Ca)) sensitive to benzothiazepine (diltiazem) and phenylalkylamine (verapamil) derivatives; 4) a Ca(2+)-activated Cl- current (I(Cl(Ca))); and 5) a plasma membrane Ca(2+)-ATPase. The Ca2+ current showed a range of activation from positive potentials to -60 mV with a maximum between -30 and -20 mV. In contrast to other L-type Ca2+ channels, rod Ca2+ channels were blocked at similar and relatively high concentrations by the diltiazem isomers and verapamil. The biphasic dose-response for D-diltiazem confirmed the low sensitivity of Ca2+ channels for the molecule. The ATPase, which was localized at the axon terminal, was found to contribute to Ca2+ extrusion. These results suggest that the electrophysiological features of rod photoreceptors had been preserved during evolution from nonmammalian vertebrates to mammals. This work indicates further that mammalian rods express nonclassic L-type Ca2+ channels, showing a low sensitivity to the diltiazem isomers used in neuroprotective studies.

Constitutive expression of CCR2 chemokine receptor and inhibition by MCP-1/CCL2 of GABA-induced currents in spinal cord neurones.

In the CNS, immune-like competent cells (microglia and astrocytes) were first described as potential sites of chemokine synthesis, but more recent evidence has indicated that neurones might also express chemokines and their receptors. The aim of the present work was to investigate further, both in vivo and in vitro, CC Chemokine Family Receptor 2 (CCR2) expression and functionality in rat spinal cord neurones. First, we demonstrated by RT-PCR and western blot analysis that CCR2 mRNA and protein were present in spinal extracts. Furthermore, we showed by immunolabelling that CCR2 was exclusively expressed by neurones in spinal sections of healthy rat. Finally, to test the functionality of CCR2, we used primary cultures of rat spinal neurones. In this model, similar to what was observed in vivo, CCR2 mRNA and protein were expressed by neurones. Cultured neurones stimulated with Monocyte Chemoattractant Protein-1 (MCP-1)/CCL2, the best characterized CCR2 agonist, showed activation of the Akt pathway. Finally, patch-clamp recording of cultured spinal neurones was used to investigate whether MCP-1/CCL2 could modulate their electrophysiological properties. MCP-1 alone did not affect the electrical properties of spinal neurones, but potently and efficiently inhibited GABA(A)-mediated GABAergic responses in these neurones. These data constitute the first demonstration of a modulatory role of MCP-1 on GABAergic neurotransmission and contribute to our understanding of the roles of CCR2 and MCP-1/CCL2 in spinal cord physiology, in particular with respect to nociceptive transmission, as well as the implication of this chemokine in neuronal adaptation or dysfunction during neuropathy.

Cholecystokinin-like immunoreactive amacrine cells in the rat retina.

High levels of endogenous cholecystokinin (CCK) are present in the rat retina (Eskay & Beinfeld, 1982), but the cellular localization and physiological actions of CCK in the rat retina are uncertain. The goals of this study were to characterize the cells containing CCK, identify cell types that interact with CCK cells, and investigate the effects of CCK on rod bipolar cells. Rat retinas were labeled with antibody to gastrin-CCK (gCCK) using standard immunofluorescence techniques. Patch-clamp methods were used to record from dissociated rod bipolar cells from rats and mice. Gastrin-CCK immunoreactive (-IR) axons were evenly distributed throughout the retina in stratum 5 of the inner plexiform layer of the rat retina. However, the gCCK-IR somata were only detected in the ganglion cell layer in the peripheral retina. The gCCK-IR cells contained glutamate decarboxylase, and some of them also contained immunoreactive substance P. Labeled axons contacted PKC-IR rod bipolar cells, and recoverin-IR ON-cone bipolar cells. CCK-octapeptide inhibits GABA(C) but not GABA(A) mediated currents in dissociated rod bipolar cells.