Publications by authors named "Concha I"

Background: The time dedicated to patients and how they are treated are crucial in the evaluation of health care quality. Medical students acting as medical assistants could improve the perception of a good quality of care among ambulatory patients.

Aim: To evaluate if the presence of Student-Assistants improves the patients' perception of health care quality in ambulatory primary care.

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In the early days of plastination, plastinate Color was the usual grey/brown familiar to formalin-fixed biological specimens. Initially, trials with Kaiserling's, Klotz, Jore's and McCormick's fixative solutions were disappointing. Vascular injections with Colored epoxy were a great breakthrough in the 1980s.

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Article Synopsis
  • The article discusses research on the increased expression of a specific transporter, mitSVCT2, in breast cancer, highlighting its importance.
  • Various breast cancer cell lines were studied using techniques like RT-PCR and Western blot to measure SVCT2 expression levels.
  • The researchers also examined where SVCT2 is located within the cells and analyzed tissue samples to see how this transporter behaves in actual cancer tissues.
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The potential role of vitamin C in cancer prevention and treatment remains controversial. While normal human cells obtain vitamin C as ascorbic acid, the prevalent form of vitamin C in vivo, the uptake mechanisms by which cancer cells acquire vitamin C has remained unclear. The aim of this study is to characterize how breast cancer cells acquire vitamin C.

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Background: The etiology of a streptococcal pharyngitis must be documented by laboratory techniques to avoid unnecessary antimicrobial treatment, but this strategy increases cost for the patient. Available scores applied in children or adults are imperfect.

Aim: To develop a clinical prediction rule to aid the diagnostic process of streptococcal pharyngitis (SP) in children in a low-resource setting.

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Sertoli cells provide the nutritional and metabolic support for germ cells. Wnt/β-catenin signaling is important for the development of the seminiferous epithelium during embryonic age, although after birth this pathway is downregulated. Cx43 gene codes for a protein that is critical during testicular development.

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Aims: Huntington's disease (HD) is a neurodegenerative disorder characterized by progressive abnormalities in cognitive function, mental state, and motor control. HD is characterized by a failure in brain energy metabolism. It has been proposed that monocarboxylates, such as lactate, support brain activity.

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The common embryonic origin has been a recurrent explanation to understand the presence of "neural receptors" in sperm. However, this designation has conditioned a bias marked by the classical neurotransmission model, dismissing the possibility that neurotransmitters can play specific roles in the sperm function by themselves. For instance, the launching of acrosome reaction, a fundamental sperm function, includes several steps that recall the process of presynaptic secretion.

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Interleukin-3 (IL-3) is a well-characterized growth factor in hematopoietic cells, but it is also expressed in other cell types with poorly described functions. Many studies have provided evidence that IL-3 plays an important role in cell survival. We have previously shown that IL-3 is able to increase glucose uptake in HEK293 cells, suggesting that this factor requires sustained glucose metabolism to promote cell survival.

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The granulocyte-macrophage colony stimulating factor (GM-CSF) is a multifunctional cytokine implicated in proliferation, differentiation, and activation of several cell types including those involved in hematopoiesis and reproduction. In the present study, the expression of the α- and β-subunit genes of GM-CSF receptor during follicular development in cattle was assessed. The spatial association of α- and β-subunits of GM-CSF with follicle stimulating hormone receptor (FSHR) and 3β-hydroxysteroid dehydrogenase (3β-HSD), and the temporal associations with gene expression of hexose transporters (GLUTs) in granulosa cells of cattle were also evaluated.

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Sertoli cell metabolism actively maintains the nutritional needs of germ cells. It has been described that after glucose incorporation in Sertoli cells, less than 1% is converted to glycogen suggesting low levels of glycogen synthase activity. Phosphorylation of muscle glycogen synthase (MGS) at serine 640 (pS640MGS) decreases its activity, and this form of the enzyme was discovered as a non-ribosomal protein that modulates the translation of a subset of transcripts in HeLa cells.

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Glycogen is the main storage form of glucose; however, the accumulation of glycogen-like glucose polymers can lead to degeneration and cellular death. Previously, we reported that the accumulation of glycogen in testis of transgenic animals overexpressing a constitutively active form of glycogen synthase enhances the apoptosis of pre-meiotic male germ cells and a complete disorganization of the seminiferous tubules. Here we sought to further identify the effects of glycogen storage in cells from the seminiferous tubules and the mechanism behind the pro-apoptotic activity induced by its accumulation.

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N-Formyl-methionyl-leucyl-phenylalanine (fMLP) and platelet-activating factor (PAF) induce similar intracellular signalling profiles; but only fMLP induces interleukin-8 (IL-8) release and nicotinamide adenine dinucleotide phosphate reduced (NADPH) oxidase activity in neutrophils. Because the role of ROS on IL-8 release in neutrophils is until now controversial, we assessed if NADPH oxidase is involved in the IL-8 secretions and PI3K/Akt, MAPK, and NF-κB pathways activity induced by fMLP. Neutrophils were obtained from healthy volunteers.

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Failure in energy metabolism and oxidative damage are associated with Huntington's disease (HD). Ascorbic acid released during synaptic activity inhibits use of neuronal glucose, favouring lactate uptake to sustain brain activity. Here, we observe a decreased expression of GLUT3 in STHdhQ111 cells (HD cells) and R6/2 mice (HD mice).

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Understanding how glucose metabolism is finely regulated at molecular and cellular levels in the liver is critical for knowing its relationship to related pathologies, such as diabetes. In order to gain insight into the regulation of glucose metabolism, we studied the liver-expressed isoforms aldolase B and fructose-1,6-bisphosphatase-1 (FBPase-1), key enzymes in gluconeogenesis, analysing their cellular localization in hepatocytes under different metabolic conditions and their protein-protein interaction in vitro and in vivo. We observed that glucose, insulin, glucagon and adrenaline differentially modulate the intracellular distribution of aldolase B and FBPase-1.

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This work analysed intracellular calcium stores of boar spermatozoa subjected to 'in vitro' capacitation (IVC) and subsequent progesterone-induced acrosome exocytosis (IVAE). Intracellular calcium was analysed through two calcium markers with different physico-chemical properties, Fluo-3 and Rhod-5N. Indicative parameters of IVC and IVAE were also evaluated.

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The development and survival of male germ cells depend on the antioxidant capacity of the seminiferous tubule. Glutathione (GSH) plays an important role in the antioxidant defenses of the spermatogenic epithelium. Autophagy can act as a pro-survival response during oxidative stress or nutrient deficiency.

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The aim of this work was to determine the existence of a functional Wnt/β-catenin signaling pathway in boar spermatozoa, which would be linked with the already well-known GSK-3 signaling pathway. This was first confirmed by detecting the presence of the specific Frizzled 3 receptor in these cells. Furthermore, this signaling pathway was activated in boar spermatozoa subjected to 'in vitro' capacitation (IVC) and subsequent progesterone-induced 'in vitro' acrosome exocytosis (IVAE) by incubating cells with separate concentrations of Wnt1 ligand, the Wnt/β-catenin signaling pathway-specific effector.

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Dopamine is a catecholamine with multiple physiological functions, playing a key role in nervous system; however its participation in reproductive processes and sperm physiology is controversial. High dopamine concentrations have been reported in different portions of the feminine and masculine reproductive tract, although the role fulfilled by this catecholamine in reproductive physiology is as yet unknown. We have previously shown that dopamine type 2 receptor is functional in boar sperm, suggesting that dopamine acts as a physiological modulator of sperm viability, capacitation and motility.

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Article Synopsis
  • Incubation of boar spermatozoa with oligomycin A leads to immediate immobilization and impairs their ability to undergo in vitro capacitation (IVC) and acrosome exocytosis (IVAE).
  • Oligomycin A does not affect oxygen consumption, ATP levels, or mitochondrial membrane potential (MMP), suggesting its inhibitory effects are independent of overall energy maintenance.
  • The study indicates that the activity of mitochondrial ATP synthase, sensitive to oligomycin A, is crucial for proper sperm motility and the successful processes of IVC and IVAE.
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Background: The most used test for the diagnosis of viral respiratory infection is the detection of viral antigens by direct immunofluorescence (DFA), in samples taken by nasopharyngeal swab (NPS) or aspirate (NPA). It would be desirable to have a less uncomfortable technique to obtain a sample from the patient, but of equal performance.

Aim: To evaluate the diagnostic agreement between nasal swab (NS) and nasopharyngeal swab (NPS) in the detection of respiratory viruses by DFA and compare the degree of discomfort of both techniques in pediatric patients.

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Background: Fructose-1,6-bisphosphatase, a major enzyme of gluconeogenesis, is inhibited by AMP, Fru-2,6-P2 and by high concentrations of its substrate Fru-1,6-P2. The mechanism that produces substrate inhibition continues to be obscure.

Methods: Four types of experiments were used to shed light on this: (1) kinetic measurements over a very wide range of substrate concentrations, subjected to detailed statistical analysis; (2) fluorescence studies of mutants in which phenylalanine residues were replaced by tryptophan; (3) effect of Fru-2,6-P2 and Fru-1,6-P2 on the exchange of subunits between wild-type and Glu-tagged oligomers; and (4) kinetic studies of hybrid forms of the enzyme containing subunits mutated at the active site residue tyrosine-244.

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Huntington's disease has been associated with a failure in energy metabolism and oxidative damage. Ascorbic acid is a powerful antioxidant highly concentrated in the brain where it acts as a messenger, modulating neuronal metabolism. Using an electrophysiological approach in R6/2 HD slices, we observe an abnormal ascorbic acid flux from astrocytes to neurons, which is responsible for alterations in neuronal metabolic substrate preferences.

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Background: The objectives of the study were to characterize the expression of the α- and β-subunits of granulocyte-macrophage colony stimulating factor (GM-CSF) receptor in bovine cumulus cells and oocytes and to determine the effect of exogenous GM-CSF on cumulus cells expansion, oocyte maturation, IGF-2 transcript expression and subsequent competence for embryonic development.

Methods: Cumulus-oocyte complexes (COC) were obtained by aspirating follicles 3- to 8-mm in diameter with an 18 G needle connected to a vacuum pump at -50 mmHg. Samples of cumulus cells and oocytes were used to detect GM- CSF receptor by immunofluorescence.

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Glycogen is the main source of glucose for many biological events. However, this molecule may have other functions, including those that have deleterious effects on cells. The rate-limiting enzyme in glycogen synthesis is glycogen synthase (GS).

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