Morpho-anatomy of in vitro germination and cryopreservation of the orchid Cattleya crispa (Orchidaceae Morfoanatomía de la germinación in vitro y criopreservación de la orquídea Cattleya crispa (Orchidaceae) / Morfoanatomía de la germinación in vitro y criopreservación de la orquídea Cattleya crispa (Orchidaceae)

Introduction: Cattleya crispa is an ornamental epiphytic orchid with geographic distribution restricted to the Brazilian Atlantic Forest. Due to predatory extractivism and human-induced habitat loss, this species appears on the Red List of Brazilian Flora. Objective: To characterize morpho-anatomical aspects regarding germination and post-seminal development from C. crispa seeds; as well as studying the effect of cryopreservation on these seeds. Methods: We used light microscopy and electron microscopy to describe the microstructure of a 100 ripe seeds. We evaluated seed viability, seed germination, survival rate and protocorm weight in cryopreserved and non-cryopreserved material, with four replicas per treatment using 20 mg of plant material. Results: The seeds are fusiform, whitish yellow with a length from 700 to 900 µm and a water content of 5 %. Germination began seven days after sowing, the formation of the globular protocorm at 30 days and the formation of the seedling occurred 150 days. The persistent seed coat can compress the protocorm and cause it to collapse. The cryopreserved seeds presented 87.15 % viability, 78.32 % germination, 8.48 % survival and protocorms with 104.27 mg five months after sowing. Data wasn't different to non-cryopreserved seeds. Conclusions: The cryocapability of the seeds shows that cryopreservation can be used for long-term conservation. The results of this work contribute to the overall biology of C. crispa and to the propagation and storage of genetic material for conservation purposes.

Introducción: Cattleya crispa es una orquídea epífita ornamental con distribución geográfica restringida a la Mata Atlántica brasileña. Debido al extractivismo depredador y a la pérdida de hábitat inducida por el hombre, esta especie aparece en la Lista Roja de la Flora Brasileña. Objetivo: Caracterizar aspectos morfoanatómicos de la germinación y desarrollo inicial de semillas de C. crispa; así como estudiar el efecto de la criopreservación de estas semillas. Métodos: Utilizamos microscopía óptica, microscopía electrónica de barrido y microscopía electrónica de transmisión para describir la microestructura en 100 semillas maduras. Evaluamos la viabilidad de la semilla, la germinación de la semilla, la tasa de supervivencia y el peso de los protocormos en el material criopreservado y no criopreservado, con cuatro réplicas por tratamiento de 20 mg de material vegetal. Resultados: Las semillas son fusiformes, amarillo blanquecinas, con una longitud de 700 a 900 µm y un contenido de agua del 5 %. La germinación comenzó siete días después de la siembra, la formación del protocormo globular a los 30 días y la formación de la plántula a los 150 días. La cubierta de semilla persistente puede comprimir el protocormo y provocar su colapso. Las semillas criopreservadas presentaron 87.15 % de viabilidad, 78.32 % de germinación, 8.48 % de supervivencia y protocormos con 104.27 mg a los cinco meses de la siembra. Los datos no fueron diferentes a las semillas no criopreservadas. Conclusiones: La capacidad criogénica de las semillas muestra que la crioconservación puede utilizarse para la conservación a largo plazo. Los resultados de este trabajo contribuyen a la biología general de C. crispa y a la propagación y almacenamiento de material genético con fines de conservación.

Curative Pericardiectomy in Interpheron-Resistant Severe Pericardial Erdheim-Chester Disease.

Erdheim-Chester disease is a rare clonal non-Langerhans cell histiocytosis with multisystemic involvement. It affects bones, large vessels, and retroperitoneum. Cardiac involvement is one of the main mortality predictors.1 We present an unusual case that debuted with cardiac tamponade and pericardial constriction requiring pericardiectomy for definitive control. (Level of Difficulty: Intermediate.).

Helical 6-Strand Cruciate Tenorrhaphy: Description of a New Technique and Biomechanical Comparative Analysis With 2 Standard Techniques.

Background: Multiple flexor tendon repair techniques have been developed over the last years. Despite all this, there is no standard technique that has proven to be superior to others, leading to great variability in the use of techniques in surgical practice. We describe a novel tendon repair technique and compare its biomechanical characteristics with 2 conventional techniques. Methods: Comparative experimental biomechanical study in ex vivo animal models. In all, 66 deep flexor tendons of the pig's front legs were taken and it's repair was performed by 1 of 3 techniques (helical 6-strand cruciate tendon repair, Adelaide tendon repair, or modified Kessler). These repairs were subjected to biomechanical study, measuring, and registering the ultimate tensile strength, load to 2-mm gap force, and stiffness. Results: The helical 6-strand cruciate tenorrhaphy compared with the Adelaide and modified Kessler techniques carries statistically significant greater ultimate tensile strength before failure (65.5, 46, and 36 N, respectively, P < .001). It also required a greater load to 2-mm gap force and is less stiff, allowing greater strain before failure. This technique does not generate significant changes in the dimensions of the tendons compared to the others, and there was no significant difference in the strength of repair between surgeons. Conclusions: The helical 6-strand cruciate tenorrhaphy is a novel technique, useful for the repair of flexor tendons in the hand that holds up the necessary forces to initiate early mobilization in the postoperative period and has better biomechanical properties than 2 standard techniques.

Malocclusion Management Following Mandibular Reconstruction With Free Fibula Flaps.

STUDY DESIGN: Free fibula flaps are nowadays the gold standard for the surgical reconstruction on large mandibular defects. Malocclusion is an important complication of this type of reconstruction and many of these patients end up requiring subsequent orthognathic corrective surgery. This is a descriptive retrospective case series study. OBJECTIVE: To describe the demographic data, operative techniques, corrective methods and postoperative results in the management of malocclusion following mandibular reconstruction with free fibula flap. METHODS: This case series study included patients who underwent free fibula flap mandibular reconstructions and who that subsequently developed malocclusion requiring orthognathic corrective surgery, from June 2010 to December 2019. Panoramic X-rays, cephalometries and/or 3-D facial reconstruction CT scans were used for surgical planning to create surgical cutting guides, templates and occlusal splints in all the patients that underwent corrective orthognathic surgery. RESULTS: There were 46 patients who underwent a free fibula flap mandibular and maxillary reconstruction at San Jose Hospital between June 2010 and December 2019 of these, 5 patients (10.9%) developed postoperative malocclusion. One case from another institution was added to this study for a total of 6 patients with malocclusion following mandibular reconstruction surgery with a fibula free flap. During the orthognathic surgery, vertical osteotomies were performed in 3 patients and bilateral sagittal split osteotomies were necessary in 2 patients and L-shape in 1 patient. Osteogenic distraction was performed in 3 patients as part of their orthognathic treatment. The fixation methods were based in miniplates for 3 of the patients and lag screws for the remaining 3 patients. With this approach, all patients had an adequate occlusion correction with a 100% consolidation at their 6-month follow up. CONCLUSION: Malocclusion is a significant complication following mandibular reconstruction surgery that must be identified and managed. In severe cases, it requires corrective orthognathic surgery in severe cases. We have developed a protocol to avoid pitfalls during the primary reconstruction and in case an orthognathic surgery is required for malocclusion correction, preoperative planning with cutting guides and occlusal splints should be assessed, to guarantee favorable results through a reproducible technique.

Adsorción de un complejo de hierro sobre nanocristales de dióxido de titanio utilizando un residuo piridina / Adsorption of an iron complex on nanocrystals of titanium dioxide using a pyridine residue / Adsorção de um complexo de ferro em nanocristais de dióxido de titânio usando um resíduo de piridina

Resumen Debido a que los fenómenos de adsorción de tinturas sobre óxidos metálicos son de gran importancia en la búsqueda de sistemas de conversión de energía solar, en este trabajo se presenta el comportamiento espectroscópico y electroquímico del complejo [Fe(pytpy2)] (PF6)2 (donde pytpy es 4'-(piridin-4-il)-2,2':6',2"-terpiridina) en solución fluida y anclado sobre una película delgada de nanocristales de dióxido de titanio. La constante de formación del aducto se estimó utilizando el modelo isotérmico de Langmuir y se encontró un valor de 1,03x105 M-1 para dicho complejo. El anclaje del complejo sobre la superficie del óxido metálico semiconductor se debe a la interacción del residuo de piridina con los sitios ácidos de Lewis presentes en la superficie del TiO2. Se observó que las propiedades espectroscópicas y electroquímicas del complejo no se ven modificadas por la adsorción.

Abstract Because the phenomena of adsorption of tinctures on metal oxides are of great importance in the search for solar energy conversion systems, this paper presents the spectroscopic and electrochemical behavior of the complex [Fe(pytpy2)](PF6)2 (where pytpy is 4'-(4-pyridyl)-2,2':6',2''-terpyridine) in a fluid solution and anchored on a thin film of nanocrystals of titanium dioxide. The adduct formation constant was estimated using the Langmuir isothermal model, with a value of 1.03x105 M-1 for the complex. The anchoring of the complex on the surface of the semiconductor metal oxide is due to the interaction of the pyridine residue with the Lewis acid sites presented on the TiO2 surface. Results indicated that the spectroscopic and electrochemical properties of the complex are not modified by the adsorption.

Resumo Os fenômenos de adsorção de tinturas em óxidos metálicos são de grande importância na busca por sistemas de conversão de energia solar, motivo pelo qual neste trabalho o comportamento espectroscópico e eletroquímico do complexo [Fe(pytpy2)] (PF6)2 (onde pytpy é 4'-(piridin-4-il)-2,2':6',2"-terpiridina) em uma solução fluida e ancorada em um filme fino de nanocristais de dióxido de titânio. A constante de formação de aduto foi estimada pelo modelo isotérmico de Langmuir, com valor de 1.03x105 M-1 para o referido complexo. A ancoragem do complexo na superfície do óxido de metal semicondutor é devida à interação do resíduo de piridina com os sítios de ácido de Lewis presentes na superfície do TiO2, observando que as propriedades espectroscópicas e eletroquímicas do complexo não são modificadas pela adsorção.

Impaired expression and function of group II metabotropic glutamate receptors in pilocarpine-treated chronically epileptic rats.

Group II metabotropic (mGlu II) receptor subtypes mGlu2 and mGlu3 are important modulators of synaptic plasticity and glutamate release in the brain. Accordingly, several pharmacological ligands have been designed to target these receptors for the treatment of neurological disorders characterized by anomalous glutamate regulation including epilepsy. In this study, we examine whether the expression level and function of mGlu2 and mGlu3 are altered in experimental epilepsy by using immunohistochemistry, Western blot analysis, RT-PCR and extracellular recordings. A down-regulation of mGlu2/3 protein expression at the mossy fiber pathway was associated with a significant reduction in mGlu2/3 protein expression in the hippocampus and cortex of chronically epileptic rats. Moreover, a reduction in mGlu2 and mGlu3 transcripts levels was noticed as early as 24 h after pilocarpine-induced status epilepticus (SE) and persisted during subsequent "latent" and chronic periods. In addition, a significant impairment of mGlu II-mediated depression of field excitatory postsynaptic potentials at mossy fiber-CA3 synapses was detected in chronically epileptic rats. Application of mGlu II agonists (2S,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine (DCG-IV) induced a significant reduction of the fEPSP amplitude in control rats, but not in chronic epileptic rats. These data indicate a long-lasting impairment of mGlu2/3 expression that may contribute to abnormal presynaptic plasticity, exaggerate glutamate release and hyperexcitability in temporal lobe epilepsy.

Down-regulation of BK channel expression in the pilocarpine model of temporal lobe epilepsy.

In the hippocampus, BK channels are preferentially localized in presynaptic glutamatergic terminals including mossy fibers where they are thought to play an important role regulating excessive glutamate release during hyperactive states. Large conductance calcium-activated potassium channels (BK, MaxiK, Slo) have recently been implicated in the pathogenesis of genetic epilepsy. However, the role of BK channels in acquired mesial temporal lobe epilepsy (MTLE) remains unknown. Here we used immunohistochemistry, laser scanning confocal microscopy (LSCM), Western immunoblotting and RT-PCR to investigate the expression pattern of the alpha-pore-forming subunit of BK channels in the hippocampus and cortex of chronically epileptic rats obtained by the pilocarpine model of MTLE. All epileptic rats experiencing recurrent spontaneous seizures exhibited a significant down-regulation of BK channel immunostaining in the mossy fibers at the hilus and stratum lucidum of the CA3 area. Quantitative analysis of immunofluorescence signals by LSCM revealed a significant 47% reduction in BK channel immunofluorescent signals in epileptic rats when compared to age-matched non-epileptic control rats. These data correlate with a similar reduction in BK channel protein levels and transcripts in the cortex and hippocampus. Our data indicate a seizure-related down-regulation of BK channels in chronically epileptic rats. Further functional assays are necessary to determine whether altered BK channel expression is an acquired channelopathy or a compensatory mechanism affecting the network excitability in MTLE. Moreover, seizure-mediated BK down-regulation may disturb neuronal excitability and presynaptic control at glutamatergic terminals triggering exaggerated glutamate release and seizures.