Apendagitis epiploica como causa inusual de dolor abdominal agudo: características clínicas y radiológicas de 7 pacientes / Epiploic appendagitis as unusual cause of acute abdominal pain: clinical and radiologic features of 7 patients

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Three-Dimensional Bioprinting for Regenerative Dentistry and Craniofacial Tissue Engineering.

Craniofacial tissues are organized with complex 3-dimensional (3D) architectures. Mimicking such 3D complexity and the multicellular interactions naturally occurring in craniofacial structures represents one of the greatest challenges in regenerative dentistry. Three-dimensional bioprinting of tissues and biological structures has been proposed as a promising alternative to address some of these key challenges. It enables precise manufacture of various biomaterials with complex 3D architectures, while being compatible with multiple cell sources and being customizable to patient-specific needs. This review describes different 3D bioprinting methods and summarizes how different classes of biomaterials (polymer hydrogels, ceramics, composites, and cell aggregates) may be used for 3D biomanufacturing of scaffolds, as well as craniofacial tissue analogs. While the fabrication of scaffolds upon which cells attach, migrate, and proliferate is already in use, printing of all the components that form a tissue (living cells and matrix materials together) to produce tissue constructs is still in its early stages. In summary, this review seeks to highlight some of the key advantages of 3D bioprinting technology for the regeneration of craniofacial structures. Additionally, it stimulates progress on the development of strategies that will promote the translation of craniofacial tissue engineering from the laboratory bench to the chair side.

Pretreatment of urine samples with SDS improves direct identification of urinary tract pathogens with matrix-assisted laser desorption ionization-time of flight mass spectrometry.

We pretreated with SDS 71 urine samples with bacterial counts of >10(5) CFU/ml and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) identification scores of <2, in order to minimize failure rates. Identification improved in 46.5% of samples, remained unchanged in 49.3%, and worsened in 4.2%. The improvement was more evident for Gram-negative (54.3%) than for Gram-positive (32%) bacteria.

Effects of zinc ex vivo and intracellular zinc chelator in vivo on taurine uptake in goldfish retina.

Taurine and zinc exert neurotrophic effects. Zinc modulates Na(+)/Cl(-)-dependent transporters. This study examined the effect of zinc (ZnSO(4)) ex vivo and zinc chelator N,N,N',N'-tetrakis-(2-pyridylmethyl) ethylenediamine (TPEN) in vivo on [(3)H]taurine transport in goldfish retina. The effect of TPEN in vivo on taurine and zinc levels was determined. Isolated cells were incubated in Ringer with zinc (0.1-100 microM). Taurine transport was done with taurine (0.001-1 mM) and 50 nM [(3)H]taurine. Zinc (100 microM) noncompetitively inhibited taurine transport. TPEN was administered intraocularly and retinas extracted 3, 5 and 10 days later. Taurine was determined by HPLC (nmol/mg protein) and zinc by spectrophotometry ICP (mg/mg protein). Taurine and zinc levels decreased at 3 days and increased at 10 days after TPEN administration. At 10 days after intraocular TPEN, taurine transport affinity increased (K (s) = 0.018 +/- 0.006 vs. 0.028 +/- 0.008 mM). Apparently, zinc deficiency affects the taurine-zinc complex and taurine availability. The increased taurine uptake affinity by TPEN was possibly associated with a response to maximize retinal taurine content at low zinc concentration.

Taurine and zinc modulate outgrowth from goldfish retinal explants.

Taurine and zinc, highly concentrated in the retina, possess similar properties in this structure, such as neuro-protection, membrane stabilization, influencing regeneration, and modulating development, maybe by acting in parallel or as interacting agents. We previously demonstrated that there are some correlations between taurine and zinc levels in hippocampus, dentate gyrus and retina of the developing rat. In the present study we evaluate the possible effects of taurine and zinc on outgrowth from goldfish retinal explants. The optic nerve was crushed 10 days before plating and culturing retinal explants in Leibovitz medium with 10% fetal calf serum and gentamicin. Neurites were measured with SigmaScanPro after 5 days in culture. Taurine (HPLC) and zinc (ICP) concentrations were determined in the retina between 1 and 180 days after crushing the optic nerve. Zinc sulfate (0.01-100 microM), N,N, N',N'-tetrakis (pyridylmethyl) ethylenediamine (TPEN, 0.1-5 nM) and diethylenetriamine penta-acetic acid (DTPA, 10-300 microM), intracellular and extracellular zinc chelators, respectively, were added to the medium. TPEN was also injected intraocular (0.1 nM). Combinations of them were added with taurine (1-16 mM). Taurine concentrations were elevated in the retina 72 h after the crush, but were normalized by 180 days, those of zinc increased at 24 h, preceding the increase of taurine. The axonal transport of [3H]taurine from the optic tectum to the retina was not affected in fish with or without crush of the optic nerve at early periods after the injection, indicating an increase of it post-lesion. Zinc sulfate produced a bell-shaped concentration dependency on in vitro outgrowth, with stimulation at 0.05 microM, and inhibition at higher levels, also increased the effect of 4 mM taurine at 0.02 microM, but diminished it at higher concentrations in the medium. TPEN decreased outgrowth at 1 nM, but not at 0.5 nM, although the simultaneous presence of 4 mM taurine and 0.5 nM TPEN decreased outgrowth respecting the stimulation by taurine alone. The intraocular administration of TPEN decreased outgrowth in vitro, an effect counteracted by the addition of 4 mM taurine to the culture medium. DTPA decreased outgrowth from 10 microM in the medium. The present results indicate that an optimal zinc concentration is necessary for outgrowth of goldfish retinal explants and that, in zinc deficient retina, taurine could stimulate outgrowth. In addition, the observations of variations in tissue concentrations and of the effects of intraocular administration of TPEN indicate that these effects could occur in vivo.

Bacteriemia por Campylobacter jejuni asociada a pancreatitis aguda / Campylobacter jejuni bacteriemia associated with acute pancreatitis

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Mielolipoma de glándula suprarenal: reporte de un caso / Adrenal gland myelolipoma: report a case

Describir la clínica, imagenología y el tratamiento de esta patología poco frecuente. Servicio de Cirugía III. Hospital Universitario de Caracas. Reporte de un caso clínico y revisión de la literatura. El término mielolipoma suprarrenal fue acuñado por Oberling 1929 para denominar a una variedad de tumores benignos formados por tejido adiposo maduro y tejido meiloide hematopoyético originados en el estroma suprarrenal. Su incidencia en autopsia oscila entre 0.3 y el 0.4 por ciento(²), la misma aumenta en los pacientes obesos(²³) y es más frecuente en la 4ta a 6ta década de la vida. Dentro de los estudios diagnósticos está la resonancia magnética en donde las áreas lipomatosas muestran intensidad aumentada en T1 y moderada hiperdensidad en T2. El tratamiento recomendado cuando son mayores de 5 cm. es quirúrgico

Content and concentration of taurine, hypotaurine, and zinc in the retina, the hippocampus, and the dentate gyrus of the rat at various postnatal days.

Taurine and zinc possess neurotrophic and neuroprotective properties, and they have been demonstrated to interact in the central nervous system (CNS). The aim of this work was to determine taurine, hypotaurine, and zinc levels during postnatal development and any possible significant correlation between them in selective areas of the CNS with differential taurine level regulation and intrinsic capacity to proliferate. Taurine and hypotaurine content (nM/region) and concentration (nM/mg protein) and total zinc levels were determined in the retina, hippocampus, and dentate gyrus of the rat at postnatal days 5, 10, 15, 20, 30, and 50. Taurine and hypotaurine increased during development in the retina without significant correlation between them. In the hippocampus there was a progressive decrease, and in the dentate gyrus there was an initial increase and a posterior decrease of taurine and hypotaurine levels. Correlation between the two amino acids was observed at P10, P15, and P50 for the hippocampus and at P15, P30, and P50 for the dentate gyrus. The variations in total zinc levels followed a biphasic behavior, with an early decrease and later increase. Significant and positive correlation of zinc and taurine was only observed in the hippocampus at P30 and P50 and negative in the dentate gyrus at P30. No significant correlation was obtained for the retina. The maintenance of taurine levels in specific CNS areas does not seem to be related to the availability of the precursor, hypotaurine, which might have a role by itself. There are critical postnatal periods during which there is a preservation of taurine, hypotaurine, or zinc levels. It seems that these requirements could be related to zinc-taurine interactions.

Gastrectomía total con reconstrucción esófago-yeyuno anastomosis en Y de roux por laparoscopia: primer caso en el Hospital Universitario de Caracas: descripción de la técnica / Gastrectomy all with reconstruction asophagus - jejunum anastomosis roux en Hospital Universitario de Caracas

Rorte de un primer caso realizado en el Hospital Universitario de Caracas, de un paciente masculino de 46 años de edad, con neoplasia intra epitelial de lato grado en fundus gástrico, a quién se le realiazó gastrectomía total con reconstrucción asófago-yeyuno anatomosis en "Y" de Roux término - lateral por laparoscopia

Gastrectomía total con reconstrucción esófago-yeyuno anastomosis término-lateral por cáncer gástrico con máquina autosuturadora / Total gastrctomy with reconstruction terminal-side esophagojejunostomy for gastric cancer with autosuture

Se presentaron los casos de pacientes con diagnóstico de cáncer gástrico de trece años de cirugía, a los cuales se les realizó gastrectomía total con esófago-yeyuno anastomosis término-lateral en Y Roux con el uso de máquina autosuturadora, como técnica simplificada, segura y efectiva en el manejo de esta patología. Entre 1991 y 2004 se operaron 13 casos. Diez pacientes maculinos (76,9 por ciento) y tres pacientes femeninos (23,1 por ciento), con una edad promedio de 65,07 años. Diez (10) pacientes presentaron adenocarcinoma gástrico (ADC) del tercio superior (76,92 por ciento), uno (1) del tercio medio (7,69 por ciento). La mortalidad en el postoperatorio tardío ocurrió en dos pacientes (15,38 pacientes) por complicaciones respiratorias. La sobrevida esciló entre 22 días y 13 años, siendo en promedio de 24,13 meses. La sobrevida a los 2 años fue de 46,15 por ciento y de 7,69 por ciento a los 5 años

Effects of taurine deficiency and chronic methanol administration on rat retina, optic nerve and brain amino acids and monoamines.

A chronic methanol (MeOH) intoxication scheme (2 g/kg/day ip for 2 weeks) was carried out in Sprague-Dawley rats, previously depleted of folates with methotrexate (MTX). beta-Alanine (beta-Ala), 5%, was also administered to some animals in the drinking water. Amino acids were determined in plasma, retina, optic nerve, hippocampus and posterior cortex by HPLC with fluorescence detection and monoamines in retina, hippocampus and posterior cortex by electrochemical detection. Beta-Ala administration reduced taurine (Tau) levels in plasma, hippocampus and posterior cortex, but not in retina and optic nerve. Aspartate (Asp) concentration in the optic nerve was increased in MTX-MeOH treated animals, and the administration of beta-Ala did not modify this elevation. The association of beta-Ala with MTX-MeOH produced an increase of threonine, and a decrease of 5-hydroxytryptamine (5-HT) in the retina without modifying 5-hydroxyindoleacetic acid, whereas in the hippocampus an elevation of asparagine was observed. We conclude that, in the retina, beta-Ala in combination with MTX-MeOH increased serotonin and decreased dopamine (DA) turnover rate, and resulted in changes in the amino acid balance, that could affect glycinergic activity. On the other hand, in the hippocampus, Asp metabolism could be affected by Tau depletion with beta-Ala.

Effect of chronic methanol administration on amino acids and monoamines in retina, optic nerve, and brain of the rat.

The clinical and electroretinographic features of chronic methanol intoxication are scarce, and neurotransmitter studies have not been conducted. In addition, most of the studies in the field include results after acute administration. In the present work, a chronic methanol intoxication scheme (2 g/kg/day ip for 2 weeks) was carried out in Sprague-Dawley rats previously depleted of folates with methotrexate. Taurine (2%) in drinking water was also administered in two groups of animals. Blood formate levels were increased in methotrexate-methanol-treated animals with respect to controls (0.98 +/- 0.09 and 0.30 +/- 0.03 mM, respectively). Amino acids and monoamines were determined in plasma and in retina, optic nerve, hippocampus, and posterior cortex by HPLC with fluorescence or electrochemical detection. The main finding was an increased aspartate content in the optic nerve in methotrexate methanol-treated animals. Methanol alone increased glutamate, aspartate, glutamine, taurine, 5-hydroxytryptamine, and 5-hydroxyindoleacetic acid levels in the hippocampus and 5-hydroxytryptamine in the retina. Taurine administration had no significant effect on changes induced by methanol treatment. We concluded that chronic methanol administration produced accumulation of aspartate, an excitotoxic amino acid, in the optic nerve. These findings contribute to the understanding of methanol neurotoxicity and might indicate a relationship between chronic methanol consumption and the development of optic neuropathies.

Further characterization of 5-HT1A receptors in the goldfish retina: role of cyclic AMP in the regulation of the in vitro outgrowth of retinal explants.

The presence of serotonin 5-HT1A receptors and their physiological role were further characterized in the goldfish retina. The effects of the 5-HT6/7 receptor antagonists pimozide, fluphenazine and amoxapine, the 5-HT1A receptor antagonist WAY-100,135, and the alkylating agent N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline, on the 5-HT1A receptor agonist [3H]8-hydroxy-2-(di-n-propylamino)tetralin binding to retinal membranes, were evaluated. In addition, the effects of serotonin, 8-hydroxy-2-(di-n-propylamino)tetralin, WAY-100,135, the adenylate cyclase inhibitors SQ22536 and MDL12330A, and the cyclic AMP analog 8-bromoadenosine-3':5' cyclic monophosphate were also studied on neuritic outgrowth from retinal explants. WAY-100,135 but not 5-HT6/7 receptor antagonists inhibited [3H]8-hydroxy-2-(di-n-propylamino)tetralin binding to retinal membranes N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline decreased [3H]8-hydroxy-2-(di-n-propylamino)tetralin binding sites up to 70%, while receptor turnover was similar to that reported in other tissues. Serotonin and 8-hydroxy-2-(di-n-propylamino)tetralin stimulated cyclic AMP production, both ex vivo and in vitro, and these increases were related to inhibition of neuritic outgrowth. The inhibitory effect was reduced by SQ22536 and by WAY-100,135, and was mimicked by 8-bromoadenosine-3':5'cyclic monophosphate. This study supports previous findings about the role of serotonin as a regulator of axonal outgrowth during in vitro regeneration of the goldfish retina and demonstrates that this effect is mediated, at least in part, by 5-HT1A receptors through a mechanism which involves an increase of cyclic AMP levels.

Amino acid levels and ratios in serum and cerebrospinal fluid of patients with optic neuropathy in Cuba.

Twenty-one amino acids were determined in serum and cerebrospinal fluid of 12 patients with endemic, and in the cerebrospinal fluid of 22 patients with epidemic optic neuropathy. For the endemic patients, there was a decrease in aspartate and taurine in the serum with respect to controls. The ratios aspartate/taurine and taurine/valine were decreased, and glutamate/taurine was increased in the serum. Some of the altered amino acid ratios indicate preponderance of excitatory to inhibitory molecules. The ratio with valine corresponded to the decrease in taurine and the maintenance of valine concentration, an amino acid related to anthropometric parameters. A typical malnutrition pattern was not observed, as the levels of essential amino acids were not significantly modified. In the cerebrospinal fluid there were increases in aspartate, glutamate and threonine, the first two probably indicating a neurodegenerative disorder or some type of metabolic alteration, primary or secondary to the disease. The increase in threonine could be related to lipid metabolism, but it is not clear at present. A wide variety of amino acid ratios were increased in the cerebrospinal fluid of patients with endemic optic neuropathy, mainly pointing to an excitatory condition and some metabolic alterations. In the cerebrospinal fluid of patients with epidemic optic neuropathy there was an increase in aspartate and glutamate, and increase in glutamate/taurine, glutamate/glycine, and gamma-aminobutyric acid/glycine ratios. Interesting differences were also observed between patients from different periods of time, but with the same clinical features, and the modifications of amino acid concentrations in the cerebrospinal fluid, such as glutamine, threonine and tryptophan. The present results indicate a disorder in the metabolism of amino acids, support a specific deficit, especially for taurine, an imbalance between excitatory and inhibitory amino acids, and a possible relation to viral infections.

Taurine as a micronutrient in development and regeneration of the central nervous system.

Taurine is an amino acid known to possess trophic properties in the central nervous system. The relevance of its presence in maternal milk is related to its role as an essential nutrient. Taurine deficiency around birth produces anatomical and functional modifications in the brain and in the retina. In addition, taurine favors neuron proliferation and survival, as well as neurite extension. The mechanisms by which taurine exerts its trophic role in the regenerating retina are related to increases in calcium fluxes, to modifications of protein phosphorylation, and to influence of the target organ. Moreover, taurine-zinc interaction might be crucial in the development of structures such as the hippocampal formation. Thus, taurine can be considered as one of the determinant nutritional molecules during development and regeneration of the central nervous system.

Taurine, glutamate and GABA modulate the outgrowth from goldfish retinal explants and its concentrations are affected by the crush of the optic nerve.

The amino acid taurine plays an important trophic role during development and regeneration of the central nervous system. Other amino acid systems, such as those for glutamate and gamma-aminobutyric acid (GABA), are modified during the same physiological and pathological processes. After crushing the optic nerve, goldfish retinal explants were plated in the absence and in the presence of different amino acids and amino acid receptor agonists. The length and the density of the neurites were measured at 5 days in culture. Taurine increased the length and the density of neurites. Glutamate and glycine increased them at low concentration, but were inhibitors at higher concentration. The combination of N-methyl-D-aspartate (NMDA) and glycine produced a greater inhibitory effect than NMDA alone. NMDA or alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) added simultaneously with taurine impaired the stimulatory effect of the latter. GABA stimulated the emission of neurites in a concentration dependent manner. Hypotaurine also elevated the length of neurites, but cysteinsesulfinic acid did not produce a significant effect. The concentrations of taurine, glutamate and GABA were determined by HPLC with fluorescent detection in the retina of goldfish at various days post-crushing the optic nerve. The levels of taurine were significantly increased at 48h after the crush, and were elevated up to 20 days. Glutamate level decreased after the lesion of the optic nerve and was still low at 20 days. GABA concentration was not significantly different from the control. The interaction of these amino acids during the regenerative period, especially the balance between taurine and glutamate, may be a determinant in restoring vision after the crush.