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Keloids are defined histopathologically as an inflammatory disorder characterized by exhibiting numerous fibroblasts, abnormal vascularization, increased number of proinflammatory immune cells as well as uncontrolled cell proliferation, and exacerbated and disorganized deposition of extracellular matrix (ECM) molecules. Importantly, many of these ECM molecules display N- and O-linked glycan residues and are considered as potential targets for galectin-1 (Gal-1) and galectin-3 (Gal-3). Nevertheless, the presence and localization of Gal-1 and Gal-3 as well as the interactions with some of their binding partners in keloid tissues have not been considered. Here, we show that in the dermal thickening of keloids, versican, syndecan-1, fibronectin, thrombospondin-1, tenascin C, CD44, integrin ß1, and N-cadherin were immunolocalized in the elongated fibroblasts that were close to the immune cell infiltrate, attached to collagen bundles, and around the microvasculature and in some immune cells. We also show that Gal-1 and Gal-3 were present in the cytoplasm and along the cell membrane of some fibroblasts and immune and endothelial cells of the dermal thickening. We suggest that Gal-1 and Gal-3, in concert with some of the ECM molecules produced by fibroblasts and by immune cells, counteract the inflammatory response in keloids. We also proposed that Gal-1 and Gal-3 through their binding partners may form a supramolecular structure at the cell surface of fibroblasts, immune cells, endothelial cells, and in the extracellular space that might influence the fibroblast morphology, adhesion, proliferation, migration, and survival as well as the inflammatory responses.
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Derme/química , Fibroblastos/química , Galectina 1/análise , Galectina 3/análise , Queloide/metabolismo , Adolescente , Adulto , Biomarcadores/análise , Proteínas Sanguíneas , Derme/patologia , Feminino , Fibroblastos/patologia , Galectinas , Humanos , Imuno-Histoquímica , Queloide/patologia , Masculino , Ligação Proteica , Adulto JovemRESUMO
Snooks C. undecimalis and C. ensiferus are important fishery resources in their distribution area. In Venezuela they are caught by artisanal fisheries along the entire coast. However, studies on their biology that would help establish fishing regulations are scarce. To study reproduction aspects of these species, we analyzed 1 325 individuals of C. undecimalis and 2 025 of C. ensiferus caught by artisanal fishing in the Laguna de Tacarigua in Northern Venezuela, from July 2009 to September 2010. Total length, total weight, sex and stage of gonadal development were recorded. The sex ratio varied throughout the year: there was a significant difference in favor of C. undecimalis males (1.5:1), and C. ensiferus females (1:3.3). Differences were also evident in the sexual proportion at each size group. For both species, males dominated in the lower size ranges while females dominated in the larger size ranges. These results suggested sequential hermaphroditism (protrandry) in both species. Size at sexual maturity (Lm50) for C. undecimalis was â= 73.6 and â= 59.3 cm, and â= 26 and â= 21.5 cm for C. ensiferus. C. ensiferus reproduced throughout the year with two periods of higher intensity (August to September and February to April). Although we found very few mature individuals for C. undecimalis, February showed an important reproduction peak. Growth differences were found between males and females of C. undecimalis: positive allometry for females (P= 0.0022*L3.353) and negative allometry for males (P= 0.0108*L2.945). Both males and females of C. ensiferus showed a positive allometric relationship (P= 0.0049*L3.235). Lack of fishing regulations and controls, evidenced in this study by significant volumes of immature individuals in the catches, and the particular reproductive biology of these species, strongly indicates the need to establish regulations to ensure their responsible use. We recommend establishing a closed season during the first quarter of the year and minimum catch sizes for both species.
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Perciformes/fisiologia , Reprodução/fisiologia , Distribuição Animal , Animais , Tamanho Corporal , Feminino , Gônadas/fisiologia , Masculino , Valores de Referência , Estações do Ano , Fatores Sexuais , Razão de Masculinidade , Maturidade Sexual , Fatores de Tempo , VenezuelaRESUMO
The increase in the intracellular Ca(2+) concentration ([Ca(2+)]i) is the key variable for many different processes, ranging from regulation of cell proliferation to apoptosis. In this work we demonstrated that the sphingolipid sphingosine (Sph) increases the [Ca(2+)]i by inhibiting the sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA), in a similar manner to thapsigargin (Tg), a specific inhibitor of this Ca(2+) pump. The results showed that addition of sphingosine produced a release of Ca(2+) from the endoplasmic reticulum followed by a Ca(2+) entrance from the outside mileu. The results presented in this work support that this sphingolipid could control the activity of the SERCA, and hence sphingosine may participate in the regulation of [Ca(2+)]I in mammalian cells.
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Cálcio/metabolismo , Neoplasias/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Esfingosina/metabolismo , Linhagem Celular Tumoral , Retículo Endoplasmático/metabolismo , Ativação Enzimática , HumanosRESUMO
Proteus mirabilis is a human pathogen able to form biofilms on the surface of urinary catheters. Little is known about P. mirabilis biofilms on natural or industrial surfaces and the potential consequences for these settings. The main aim of this work was to assess and compare the adhesion and biofilm formation of P. mirabilis strains from different origins on chitin and stainless steel surfaces within 4 to 96 h. Using environmental scanning electron microscopy, the biofilms of a clinical strain grown on chitin at 4 h showed greater adhesion, aggregation, thickness, and extracellular matrix production than those grown on stainless steel, whereas biofilms of an environmental strain had less aggregation on both surfaces. Biofilms of both P. mirabilis strains developed different structures on chitin, such as pillars, mushrooms, channels, and crystalline-like precipitates between 24 and 96 h, in contrast with flat-layer biofilms produced on stainless steel. Significant differences (p < 0.05) were found in the frequency of pillars and channels. Images of transmission electron microscopy demonstrated abundant fimbriae in 100 % of cells from both strains, which could be related to surface adherence and biofilm formation. This represents the first study of P. mirabilis showing adhesion, biofilm formation, and development of different structures on surfaces found outside the human host.
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Routine coagulation tests on a 14year-old male with frequent epistaxis showed a prolonged thrombin time together with diminished functional (162mg/dl) and gravimetric (122mg/dl) fibrinogen concentrations. His father showed similar aberrant results and sequencing of the three fibrinogen genes revealed a novel heterozygous nonsense mutation in the FGB gene c.1105C>T, which converts the codon for residue Bß 339Q to stop, causing deletion of Bß chain residues 339-461. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and RP-HPLC (reverse-phase high-pressure liquid chromatography) of purified fibrinogen showed only normal Aα, Bß, and γ chains, indicating that molecules with the truncated 37,990Da ß chain were not secreted into plasma. Functional analysis showed impaired fibrin polymerization, fibrin porosity, and elasticity compared to controls. By laser scanning confocal microscopy the patient's fibers were slightly thinner than normal. Electrospray ionization mass spectrometry (ESI MS) presented normal sialylation of the oligosaccharide chains, and liver function tests showed no evidence of liver dysfunction that might explain the functional abnormalities.
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Afibrinogenemia/genética , Códon sem Sentido , Fibrinogênio/genética , Mutação , Adolescente , Afibrinogenemia/sangue , Afibrinogenemia/diagnóstico , Coagulação Sanguínea , Fibrina/metabolismo , Fibrinogênio/metabolismo , Humanos , Masculino , Multimerização ProteicaRESUMO
We have previously demonstrated that rat type-1 cerebellar astrocytes express a very active Na(+)/Ca(2+) exchanger which accounts for most of the total plasma membrane Ca(2+) fluxes and for the clearance of Ca (i) (2+) induced by physiological agonist. In this chapter, we have explored the mechanism by which the reverse Na(+)/Ca(2+) exchange is involved in agonist-induced Ca(2+) signalling in rat cerebellar astrocytes. Laser-scanning confocal microscopy experiments using immunofluorescence labelling of Na(+)/Ca(2+) exchanger and RyRs demonstrated that they are highly co-localized. The most important finding presented in this chapter is that L-glutamate activates the reverse mode of the Na(+)/Ca(2+) exchange by inducing a Na(+) entry through the electrogenic Na(+)-glutamate co-transporter and not through the ionophoric L-glutamate receptors as confirmed by pharmacological experiments with specific blockers of ionophoric L-glutamate receptors, electrogenic glutamate transporters and the Na/Ca exchange.
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Astrócitos/metabolismo , Sinalização do Cálcio/fisiologia , Cerebelo/metabolismo , Ácido Glutâmico/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Animais , Astrócitos/citologia , Cálcio/metabolismo , Cerebelo/citologia , Ácido Glutâmico/genética , Humanos , Proteínas do Tecido Nervoso/genética , Ratos , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Sódio/metabolismo , Trocador de Sódio e Cálcio/genéticaRESUMO
Developmental venous anomalies (DVAs) are composed of mature venous vessels that lack malformed or neoplastic elements. Although the hemorrhage risk is considered negligible, some patients may have neurological symptoms attributable to acute infarction or intracranial hemorrhage secondary to thrombosis, in the absence of a coexisting cavernous malformation. We report the case of a 42-year-old patient who presented with acute left-hand paresis secondary to a subcortical hemorrhage. This bleeding originated from a DVA in the corticospinal tract area and was surgically drained through an awake craniotomy. To accomplish this, we used a trans-precentral sulcus approach. After the complete removal of the coagulum, small venous channels appeared, which were coagulated. No associated cavernoma was found. Although the main DVA trunk was left patent, no signs of ischemia or venous infarction were observed after coagulating the small venous channels found inside the hematoma cavity. Two weeks after the procedure, the patient's hand function improved, and he was able to resume desktop work. DVA-associated hemorrhage within the cortico-spinal tract could be safely removed with modern awake mapping techniques. This technique allowed the patient to rapidly improve his hand function.
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BACKGROUND: Minimally invasive spine surgery (MISS) represents a major development in spinal tumor surgery. However, considering that many intradural lesions compromise multiple spinal segments, MISS has certain limitations. Thus, some intraspinal lesions still require traditional approaches. Because laminectomy has been shown to predispose patients to kyphosis, laminoplasty and hemilaminectomy are the most widely used approaches to preserve the posterior tension band (PTB). However, these techniques are not devoid of complications. To overcome these issues, the authors modified a previously described technique to preserve the PTB while removing various types of intradural lesions. This procedure was originally designed to treat lumbar stenosis and was modified to avoid muscle ischemia during long procedures. OBSERVATIONS: Between 2014 and 2021, the authors found 17 cases of spinal lesions with a minimum of 2 years of follow-up after surgical treatment using their approach. No significant postoperative changes in the paraspinal Goutallier grade or spinal angles were observed. The cross-sectional area of the measured paraspinal muscles decreased 6% postoperatively. By performing certain technical modifications in this PTB-sparing (PBS) laminectomy, the authors avoided ipsilateral muscle ischemia. LESSONS: In this initial series, PBS laminectomy proved to be a safe, versatile, inexpensive, and reliable technique to remove intraspinal lesions.
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Bovine respiratory disease (BRD) is the leading cause of morbidity in feedlot cattle. The ability to accurately identify the expected BRD risk of cattle would allow managers to detect high-risk animals more frequently. Five classification models were built and evaluated towards predicting the expected BRD risk (high/low) of feedlot cattle within the first 45 days on feed (DOF) and incorporate an economic analysis to determine the potential health cost advantage when using a predictive model compared with standard methods. Retrospective data from 10 U.S. feedlots containing 1733 cohorts representing 188,188 cattle with known health outcomes were classified into high- (≥15% BRD morbidity) or low- (<15%) BRD risk in the first 45 DOF. Area under the curve was calculated from the test dataset for each model and ranged from 0.682 to 0.789. The economic performance for each model was dependent on the true proportion of high-risk cohorts in the population. The decision tree model displayed a greater potential economic advantage compared with standard procedures when the proportion of high-risk cohorts was ≤45%. Results illustrate that predictive models may be useful at delineating cattle as high or low risk for disease and may provide economic value relative to standard methods.
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Background: The endonasal endoscopic approach (EEA) has potential advantages over traditional open approaches. However, complications such as cerebrospinal fluid (CFS) leak, visual disturbances, and postoperative meningitis have been described. The aim was to present the experience accumulated in 120 cases of skull base EEA performed by the same surgical team and describe and analyze the main postoperative complications according to the complexity of the cases. Methods: Retrospective study on our database of patients undergoing skull base EEA for various pathologies between July 2011 and March 2022. Results: 120 skull base EEA surgeries were analyzed. 57.14% were performed on women. The median age was 44 years. 26.66% were reinterventions. The most frequent pathology was pituitary adenoma (49.17%) followed by CSF leak (8.33%). The most used EEA was the transelar 65.83%. 26 complications were recorded, with no differences according to complexity. There were 13 cases of diabetes insipidus (DI) and 8 of CSF leak. This was more frequent in patients with intraoperative CSF leak. The median hospital stay was 5.5 days. Conclusion: Skull base EEA has become increasingly common for the surgical management of skull base pathology, with a low frequency of immediate postoperative complications and low mortality. The improvement of the technique and the improvement in postoperative care are associated with a shorter hospital stay.
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Bovine respiratory disease (BRD) is a frequent disease in feedlot cattle, but little is known on the role of pen housing conditions. The objective of this research is to use a retrospective analysis with data from 10 U.S. feedlots to determine potential associations between BRD risk during the first 45 days after arrival with pen-level management factors including the number of water sources, shared water sources, and shared fence lines. Generalized linear mixed models were used to evaluate associations between management factors, cattle demographics, and BRD incidence. The effect of shared water sources on BRD risk was modified by arrival weight and cohort size (p < 0.05). Cattle with two water sources had lower BRD morbidity (5.55% ± 0.98) compared to cattle with one water source (8.80% ± 1.50) when arrival weight was 227 kg to 272 kg, while there were few differences in heavier weight cattle. Cattle with two water sources had lower BRD morbidity (3.11% ± 0.56) compared to one water (5.50% ± 0.10) when cohort size was 100−175 head, but there were no BRD morbidity differences when bigger or smaller cohorts were evaluated. Shared fence lines and water sources were associated with BRD risk; however, no biologically meaningful results were identified. The number of water sources was associated with BRD risk, and effects were modified by cohort size and arrival weight.
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INTRODUCTION: Pyogenic granuloma (PG) is a reactive inflammatory vascular lesion of the skin and mucous membranes, characterised by the presence of enlarged venules and seamed and seamless capillaries with plump endothelial cells (EC), and numerous macrophages. EC activation upregulates the synthesis of galectins and induces their translocation to the EC surface promoting angiogenesis and lymphangiogenesis, particularly galectin-1 (Gal-1), Gal-3 and Gal-8. However, the presence and distribution of Gal-1, -3 and -8, as well as their implications in the pathogenesis of PG, has not been considered. MATERIALS AND METHODS: Eight biopsies from patients diagnosed with PG were selected. The presence of PECAM-1/CD31, IL-1ß, VEGF-C, VEGFR-2, VEGFR-3, integrin ß1, CD44, fibronectin and Gal-1, -3 and -8 was assessed by immunofluorescence staining using confocal laser scanning microscopy. RESULTS AND DISCUSSION: Immunostaining revealed that these molecules were present in the enlarged venules with plump ECs, in some macrophages and other immune cells. We propose that macrophages release VEGF-A and VEGF-C inducing VEGFR-2/VEGFR-3 expression and activation, leading macrophages to transdifferentiate into plump ECs that might integrate into pre-existing venules, contributing to the formation of enlarged venules with transluminal bridges and capillaries. EC activation, induced by certain cytokines, has been shown to stimulate galectin expression and changes in the cellular localisation through association and activation of specific EC surface glycoproteins. Therefore, it is plausible that Gal-1, -3 and -8, acting in a concerted manner, could be mediating the transdifferentiation of macrophages into plump ECs and facilitating their migration and incorporation into the new vessels. LAY SUMMARY: In this study, immunostaining of pyogenic granuloma (PG) tissue sections showed immunoreactivity for PECAM-1/CD31, IL-1ß, VEGF-C, VEGFR-2 and VEGFR-3, and galectin-1, -3 and -8 in enlarged venules with plump endothelial cells (EC), as well as in some macrophages and other immune cells. Interestingly, enlarged and thin-walled transient vessels lined by PECAM-1/CD31 and VEGFR-2 immunopositive ECs that form from pre-existing normal venules in response to VEGF-A (called 'mother' vessels [MV]) and that undergo intraluminal bridging evolving into various types of capillaries (called 'daughter' vessels [DV]) have been observed in benign and malignant tumours, in physiological and pathological angiogenesis as well as in vascular malformations, suggesting an important role for VEGF-A and VEGFR-2 in such a process. However, it is not only the mechanisms by which the MVs evolve in different types of DVs that remains to be elucidated, but also whether the cells that form intraluminal bridges proceed from locally activated ECs or whether they are derived from bone marrow precursors or from resident macrophages.Given that the formation of homodimers by Gal-1 and Gal-8 and pentamers by Gal-3 to generate gal-glycan lattices at the cell surface and in the extracellular space has been shown, it is possible that in PG tissue Gal-1, -3 and -8, through their binding partners, form a supramolecular structure at the surface of ECs and plump ECs, macrophages and in the extracellular space that might be mediating the transdifferentiation of macrophages into plump ECs and facilitating the migration and incorporation of these cells into the pre-existing venules, thus contributing to the formation of MVs and DVs.
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BACKGROUND: Awake craniotomy has become the gold standard in various cranial procedures. As part of the awake technique, three-point pin fixation of the patient's head is important. One of the issues we encountered is the problem of matching the scalp infiltration site with the final pin position. To overcome this problem, we developed a flat plunger type fixator that adapts to the Mayfield holder. METHODS: Our fixator has a 2.5 cm metallic shaft that articulates in a ball and socket joint to allow its concave surfaces to adapt to the patient's scalp. After placing the patient in the desired position, the head is fixed with the three plungers, circles are drawn around each plunger, and they are then removed for the circles to be infiltrated with bupivacaine. Standard fixation pins are then placed in the Mayfield holder and aimed at the center of the circles. RESULTS: So far, we have operated on 14 patients with this technique. No patient experienced pain during temporary fixation, and the drawn circles ensured that there were no mismatches between the local anesthetic and pin locations. The technique was particularly useful on hairy scalps, where infiltration sites were hidden. We also used only 22.5 mg bupivacaine at the pin sites, freeing a dose for the field block around the scalp incision. CONCLUSION: The temporary plunger type fixator provided a simple method to economize on local anesthetic use, check the patient's head position before final fixation, and ensure that the Mayfield pins matched with the anesthetized area.
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Leishmaniasis represents a serious public health problem worldwide. The first line of treatment is based on glucantime and pentostan, which generate toxic effects in treated patients. We have recently shown that amiodarone, frequently used as an antiarrhythmic, possesses activity against Trypanosoma cruzi through the disruption of mitochondrial Ca(2+) homeostasis and the inhibition of parasite ergosterol biosynthesis, specifically at the level of oxidosqualene cyclase activity (G. Benaim, J. Sanders, Y. Garcia-Marchan, C. Colina, R. Lira, A. Caldera, G. Payares, C. Sanoja, J. Burgos, A. Leon-Rossell, J. Concepcion, A. Schijman, M. Levin, E. Oldfield, and J. Urbina, J. Med. Chem. 49:892-899, 2006). Here we show that at therapeutic concentrations, amiodarone has a profound effect on the viability of Leishmania mexicana promastigotes. Additionally, its effect on the viability of the parasite was greater against intracellular amastigotes than against promastigotes, and it did not affect the host cell. Using fluorimetric and confocal microscopy techniques, we also demonstrated that the mechanism of action of amiodarone was related to the disruption of intracellular Ca(2+) homeostasis through a direct action not only on the mitochondria but also on the acidocalcisomes. On the other hand, analysis of the free sterols in promastigotes incubated with amiodarone showed that this drug also affected the biosynthesis of 5-dehydroepisterol, which results in squalene accumulation, thus suggesting that amiodarone inhibits the squalene epoxidase activity of the parasite. Taken together, the results obtained in the present work point to a more general effect of amiodarone in trypanosomatids, opening potential therapeutic possibilities for this infectious disease.
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Amiodarona/farmacologia , Cálcio/metabolismo , Homeostase/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Esteróis/biossíntese , Animais , Células Cultivadas , Leishmania mexicana/metabolismo , Macrófagos/parasitologia , Camundongos , Microscopia Confocal , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologiaRESUMO
Rotavirus infection modifies Ca(2+) homeostasis, provoking an increase in Ca(2+) permeation, the cytoplasmic Ca(2+) concentration ([Ca(2+)](cyto)), and total Ca(2+) pools and a decrease in Ca(2+) response to agonists. A glycosylated viral protein(s), NSP4 and/or VP7, may be responsible for these effects. HT29 or Cos-7 cells were infected by the SA11 clone 28 strain, in which VP7 is not glycosylated, or transiently transfected with plasmids coding for NSP4-enhanced green fluorescent protein (EGFP) or NSP4. The permeability of the plasma membrane to Ca(2+) and the amount of Ca(2+) sequestered in the endoplasmic reticulum released by carbachol or ATP were measured in fura-2-loaded cells at the single-cell level under a fluorescence microscope or in cell suspensions in a fluorimeter. Total cell Ca(2+) pools were evaluated as (45)Ca(2+) uptake. Infection with SA11 clone 28 induced an increase in Ca(2+) permeability and (45)Ca(2+) uptake similar to that found with the normally glycosylated SA11 strain. These effects were inhibited by tunicamycin, indicating that inhibition of glycosylation of a viral protein other than VP7 affects the changes of Ca(2+) homeostasis induced by infection. Expression of NSP4-EGFP or NSP4 in transfected cells induced the same changes observed with rotavirus infection, whereas the expression of EGFP or EGFP-VP4 showed the behavior of uninfected and untransfected cells. Increased (45)Ca(2+) uptake was also observed in cells expressing NSP4-EGFP or NSP4, as evidenced in rotavirus infection. These results indicate that glycosylated NSP4 is primarily responsible for altering the Ca(2+) homeostasis of infected cells through an initial increase of cell membrane permeability to Ca(2+).
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Cálcio/metabolismo , Expressão Gênica , Glicoproteínas/metabolismo , Toxinas Biológicas/metabolismo , Proteínas não Estruturais Virais/metabolismo , Animais , Linhagem Celular , Permeabilidade da Membrana Celular , Chlorocebus aethiops , Retículo Endoplasmático/química , Glicoproteínas/genética , Humanos , Toxinas Biológicas/genética , Proteínas não Estruturais Virais/genéticaRESUMO
BACKGROUND: In healthy subjects fibrinogen γ/γ' circulates at 8-15% of the total plasma fibrinogen concentration. Elevated levels of this variant have been associated with arterial thrombosis, and its diminution with venous thrombosis. The aims of the present work were to analyze the structure of the fibrin network formed on the top of human dermal microvascular endothelial cells (HMEC-1) at different fibrinogen γ/γ' concentrations, as well as its influence on the secretion of fibrinolytic components. The kinetics of fibrin polymerization on top of HMEC-1 cells with 3, 10, and 30% fibrinogen γ/γ' was followed at 350 nm. The secretion of urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor type 1 (PAI 1) by HMEC-1 were measured in the supernatant and cell lysates, after incubation with 1 nM thrombin, fibrin with 3, and 30% fibrinogen γ/γ', using commercial kits. The influence of fibrinogen γ/γ' on fibrin structure on the surface of the HMEC-1 was followed with laser scanning confocal microscopy (LSCM). RESULTS: The kinetics of fibrin formation on HMEC-1 with 3 and 10% fibrinogen γ/γ' were similar. However, with 30% fibrinogen γ/γ' both the slope and final turbity were approximately 50% less. The LSCM images showed the dramatic effects of increasing fibrinogen γ/γ' from 3 to 30%. The uPA and PAI 1 concentrations in culture supernatants HMEC-1 cells treated with thrombin or 30% γ/γ' fibrin were two-fold increased as compared to basal culture supernatants and 3% γ/γ' fibrin-treated HMEC-1. In all stimulatory conditions the intracellular concentration of uPA was higher than in supernatants. In contrast, the intracellular PAI 1 concentration was decreased as compared to that measured in the supernatant, including the basal condition. CONCLUSION: A concentration of 30% fibrin γ/γ' alter drastically fibrin structure on the cell surface and affects the secretion of uPA and PAI 1 through its capacity to bind thrombin.
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Células Endoteliais/metabolismo , Fibrinogênios Anormais/metabolismo , Fragmentos de Peptídeos/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Trombose , Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Coagulação Sanguínea , Linhagem Celular , Fibrina/química , Fibrinogênio/química , Fibrinólise/fisiologia , Humanos , Trombina/metabolismo , Trombose/metabolismoRESUMO
Surgery of the cervical spine under conscious sedation has been rarely reported in the literature. The main indications are the lack of neurophysiological monitoring and surgery in patients with high cardiovascular risk. To date, no reports of awake C1-2 instrumentation have been published in the English-language literature. The authors present the case of a 76-year-old patient with multiple myeloma and severe cardiomyopathy associated with primary amyloidosis who experienced severe myelopathy from a C2 pseudotumor associated with an odontoid fracture. Due to his high cardiovascular risk, the patient underwent C1 decompression and C1-2 instrumentation and fusion via an awake technique. To accomplish this task, the authors performed multilayered muscular infiltration of local anesthetics and avoided manipulating the C2 root by anchoring C1 with a rod-claw system. The procedure did not last longer than that of general anesthetic approaches, and no complaints were reported by the patient during surgery, which he described as an overall "good experience." The patient was discharged on the 7th postoperative day and resumed his previous work 3 months later. Performing surgery under local anesthesia and conscious sedation reduces the risk of perioperative cardiovascular and respiratory complications in these high-risk patients by avoiding the use of drugs with cardiodepressant effects and endotracheal intubation.
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BACKGROUND: Craniocervical junction pathology is infrequent in daily neurosurgical practice. In general, most of these lesions are of traumatic or rheumatic origin. Atlantoaxial instability of inflammatory origin (Grisel syndrome) is a rare entity of which only 16 adult cases have been reported in the literature. This pathology is characterized by the development of an osteolytic lesion at the level of the atlantoaxial joint after an infectious event, usually of the upper airways. CASE DESCRIPTION: We present the case of a 76-year-old patient who attended our office for clinical symptoms of spinal instability secondary to an osteolytic lesion, with involvement of C1 and C2. The symptomatology began after an infectious respiratory process. A posterior cervical occiput fixation and an endoscopic transnasal odontoidectomy with anterior decompression were performed. The patient evolved with complete resolution of symptoms. The cultures were negative, and the pathological anatomy study concluded nonspecific inflammatory changes. CONCLUSION: Until a few years ago, the only option to address this pathology was the transoral pathway with microsurgical technique. Nowadays, endoscopy offers many technical advantages. This is an option to be considered when planning approaches to craniocervical junction.
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Collapsin Response Mediator Protein 2 (CRMP2) is an intracellular protein involved in axon and dendrite growth and specification. In this study, CRMP2 was identified in a conditioned media derived from degenerated sciatic nerves (CM). On cultured rat hippocampal neurons, acute extracellular application of CM or partially purified recombinant CRMP2 produced an increase in cytoplasmic calcium. The increase in cytoplasmic calcium was mostly mediated through NMDA receptors, with a minor contribution of N-type VDCC, and it was maintained as long as CM was present. By using live-labeling of CRMP2, Ca2+ channel binding domain 3 (CBD3) peptide derived from CRMP2, and recombinant CRMP2, we demonstrated that that this effect was mediated by an action on the extracellular side of the NMDA receptor. This is the first report of an extracellular action of CRMP2. Prolonged exposure to extracellular CRMP2, may contribute to neuronal calcium dysregulation and neuronal damage.
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Cálcio/metabolismo , Fármacos do Sistema Nervoso Central/administração & dosagem , Citoplasma/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Proteínas do Tecido Nervoso/administração & dosagem , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Cátions Bivalentes/metabolismo , Células Cultivadas , Fármacos do Sistema Nervoso Central/isolamento & purificação , Meios de Cultivo Condicionados , Citoplasma/metabolismo , Espaço Extracelular , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Camundongos , Simulação de Acoplamento Molecular , Proteínas do Tecido Nervoso/isolamento & purificação , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Nervo Óptico/metabolismo , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Proteínas Recombinantes/administração & dosagem , Nervo Isquiático/metabolismoRESUMO
Rotavirus infection is characterized by a number of Ca(2+) dependent virus-cell interactions. The structure of rotavirus triple-layered particles (TLP) is dependent on Ca(2+) concentration. Acquisition of the capsid outer layer requires a high Ca(2+) concentration inside the ER. Infection modifies Ca(2+) homeostasis of the cell, increasing ER Ca(2+) content, which may be advantageous to virus replication. We studied the role of sequestered Ca(2+) on the stabilization of already mature viral particles within the ER. Thapsigargin (TG), a SERCA pump inhibitor, added for 30min at the end of infection depleted ER Ca(2+) and reduced the titer of already mature TLP accumulated in the cell. Another inhibitor, cyclopiazonic acid, and two Ca(2+) ionophores (A23187 and ionomycin) in the presence of EGTA had similar effects. TG eliminated the peak of radiolabeled TLP, increasing that of DLP in CsCl gradients. Electron microscopy revealed accumulation of clustered particles in the ER, which had lost their integrity. The [Ca(2+)] in the ER of infected cells is important for virus maturation and for maintaining the integrity of mature TLP. Viral particles in this compartment may be potentially infectious, already containing VP7 and VP4.