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1.
Am Heart J ; 256: 95-103, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36400185

RESUMEN

BACKGROUND: After the results of the ISCHEMIA Trial, the role of myocardial ischemia in the prognosis of coronary artery disease (CAD) was under debate. We sought to comparatively evaluate the long-term prognosis of patients with multivessel CAD with or without documented myocardial ischemia. METHODS: This is a single-center, retrospective, observational cohort study that included patients with CAD obtained from the research protocols database of "The Medicine, Angioplasty or Surgery Study," the MASS Study Group. Patients were stratified according to the presence or absence of myocardial ischemia. Cardiovascular events (overall mortality and myocardial infarction) were tracked from the registry entry up to a median follow-up of 8.7 years. Myocardial ischemia was assessed at baseline by a functional test with or without imaging. RESULTS: From 1995 to 2018, 2015 patients with multivessel CAD were included. Of these, 1001 presented with conclusive tests at registry entry, 790 (79%) presenting with ischemia and 211 (21%) without ischemia. The median follow-up was 8.7 years (IQR 4.04 to 10.07). The primary outcome occurred in 228 (28.9%) patients with ischemia and in 64 (30.3%) patients without ischemia (plog-rank=0.60). No significant interaction was observed with the presence of myocardial ischemia and treatment strategies in the occurrence of the combined primary outcome (pinteration=0.14). CONCLUSIONS: In this sample, myocardial ischemia was not associated with a worse prognosis compared with no ischemia in patients with multivessel CAD. These results refer to debates about the role of myocardial ischemia in the occurrence of cardiovascular events.


Asunto(s)
Enfermedad de la Arteria Coronaria , Infarto del Miocardio , Isquemia Miocárdica , Humanos , Estudios de Seguimiento , Estudios Retrospectivos , Isquemia Miocárdica/complicaciones , Isquemia Miocárdica/epidemiología , Infarto del Miocardio/complicaciones , Pronóstico , Factores de Riesgo
2.
Eur J Pediatr ; 182(8): 3433-3443, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37258776

RESUMEN

Platelet transfusions (PTx) are the principal approach for treating neonatal thrombocytopenia, a common hematological abnormality affecting neonates, particularly preterm infants. However, evidence about the outcomes associated with PTx and whether they provide clinical benefit or harm is lacking. The aim of this systematic review and meta-analysis is to assess the association between PTx in preterm infants and mortality, major bleeding, sepsis, and necrotizing enterocolitis (NEC) in comparison to not transfusing or using different platelet count thresholds for transfusion. A broad electronic search in three databases was performed in December 2022. We included randomized controlled trials, and cohort and case control studies of preterm infants with thrombocytopenia that (i) compared treatment with platelet transfusion vs. no platelet transfusion, (ii) assessed the platelet count threshold for PTx, or (iii) compared single to multiple PTx. We conducted a meta-analysis to assess the association between PTx and mortality, intraventricular hemorrhage (IVH), sepsis, and NEC and, in the presence of substantial heterogeneity, leave-one-out sensitivity analysis was performed. We screened 625 abstracts and 50 full texts and identified 18 reports of 13 eligible studies. The qualitative analysis of the included studies revealed controversial results as several studies showed an association between PTx in preterm infants and a higher risk of mortality, major bleeding, sepsis, and NEC, while others did not present a significant relationship. The meta-analysis results suggest a significant association between PTx and mortality (RR 2.4, 95% CI 1.8-3.4; p < 0.0001), as well as sepsis (RR 4.5, 95% CI 3.7-5.6; p < 0.0001), after a leave-one-out sensitivity analysis. There was also found a significant correlation between PTx and NEC (RR 5.2, 95% CI 3.3-8.3; p < 0.0001). As we were not able to reduce heterogeneity in the assessment of the relationship between PTx and IVH, no conclusion could be taken.    Conclusion: Platelet transfusions in preterm infants are associated to a higher risk of death, sepsis, and NEC and, possibly, to a higher incidence of IVH. Further studies are needed to confirm these associations, namely between PTx and IVH, and to define the threshold from which PTx should be given with less harm effect. What is Known: • Platelet transfusions are given to preterm infants with thrombocytopenia either to treat bleeding or to prevent hemorrhage. • Lack of consensual criteria for transfusion. What is New: • A significant association between platelet transfusions and mortality, sepsis, and NEC.


Asunto(s)
Enterocolitis Necrotizante , Sepsis , Trombocitopenia , Recién Nacido , Humanos , Recien Nacido Prematuro , Hemorragia/etiología , Hemorragia/terapia , Enterocolitis Necrotizante/complicaciones , Trombocitopenia/terapia , Trombocitopenia/complicaciones , Sepsis/terapia , Sepsis/complicaciones
3.
BMC Vet Res ; 18(1): 135, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35410221

RESUMEN

BACKGROUND: Responsible companion animal guardianship (RCAG) comprises a set of concepts involving activities, behavior and care that guardians must provide to ensure the welfare of their animals. When such principles are disregarded, the risk of animals developing zoonotic diseases, such as canine visceral leishmaniasis (CVL), increases. This disease is a public health problem in many urban settings in Brazil because dogs are the main reservoirs of Leishmania and are involved in the transmission of the parasites to humans. Our analytical cross-sectional epidemiological survey aimed to investigate the prevalence of CVL in a city in southeastern Brazil and to establish the association between the disease and a number of predictor variables including dog traits, socioeconomic status of guardians, ecological features of the domicile and RCAG. RESULTS: Our study showed that the global prevalence of CVL in the sample canine population was 6.7% (47/704). All variables related to better dog care were associated with lower chances of infection. Multiple regression analysis revealed that the chances of animals being seropositive for CVL were significantly (p < 0.05) higher when guardians had no formal education or possessed a university degree (vs. those with complete primary or secondary schooling) and when dogs were sheltered outside the house and had free access to the streets. An additional novel finding was that dogs that were acquired as puppies presented half of the chance of developing the disease in comparison with those acquired at the adult stage. Geographically weighted logistic regression coefficients showed that the strengths of the predictor/CVL associations varied depending on the studied geographical space. Both models demonstrated that the associations were always in the same directions. CONCLUSIONS: Our findings indicate that regardless of age and mode of acquisition, adult dogs should be submitted to clinical evaluation and tests for CVL. RCAG can exert positive effects on the control of CVL.


Asunto(s)
Enfermedades de los Perros , Leishmaniasis Visceral , Animales , Brasil/epidemiología , Estudios Transversales , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Perros , Humanos , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/parasitología , Leishmaniasis Visceral/veterinaria , Mascotas
4.
Clin Oral Investig ; 26(12): 6985-6993, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35871702

RESUMEN

OBJECTIVES: This randomized controlled trial aimed to evaluate different protocols for dentin hypersensitivity treatment with low-power lasers and desensitizing agents, and the association between low-power lasers and desensitizing agents. MATERIALS AND METHODS: Fifty-four patients (303 teeth) were randomly allocated to three groups: G1, 3% nitrate potassium gel, UltraEZ (n = 17); G2, photobiomodulation therapy (PBM) with a low-level infrared laser (n = 17), 100 mW, spot size of 0.028 cm2, and dose of 1 J per point; and G3, nitrate potassium + PBM (n = 20). Treatments were applied to the buccal cervical region at intervals of 72 h, and all protocols were performed in three sessions. The patients' response to evaporative stimuli was rated using the visual analog scale (VAS). Re-evaluations were performed immediately after each application and 1 week, 1 month, and 3 months after treatment. A two-way repeated measures test and Tukey's post hoc test were used for multiple comparisons (α = 5%). RESULTS: There was a reduction in pain levels at the end of treatment in all groups. There were no significant differences in VAS score changes between the groups immediately after treatment and after the third month, compared to the baseline (p > 0.05). CONCLUSION: Under the limitations of this in vivo study, the proposed three-session protocol was effective in reducing dentin hypersensitivity after 3 months, regardless of the desensitization mechanism used. Conservative and long-term protocols are interesting for the control of pain caused by dentin hypersensitivity. CLINICAL RELEVANCE: The increase in cervical dentin hypersensitivity prevalence warrants easy-to-apply and long-lasting desensitizing protocols for pain control.


Asunto(s)
Desensibilizantes Dentinarios , Sensibilidad de la Dentina , Terapia por Luz de Baja Intensidad , Humanos , Sensibilidad de la Dentina/tratamiento farmacológico , Sensibilidad de la Dentina/radioterapia , Nitratos/uso terapéutico , Dolor , Potasio/uso terapéutico , Desensibilizantes Dentinarios/uso terapéutico , Resultado del Tratamiento
5.
Clin Oral Investig ; 26(2): 1915-1925, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34505917

RESUMEN

OBJECTIVES: To evaluate the effect of strontium-containing titanium- and/or magnesium-doped phosphate bioactive glass on the control of dental erosion. MATERIALS AND METHODS: Fifty fragments of human enamel were divided into five groups: negative control, 45S5 bioglass, strontium-containing Ti-doped phosphate bioactive glass (PBG-Ti), strontium-containing Mg-doped phosphate bioactive glass (PBG-Mg), and strontium-containing Ti- and Mg-doped phosphate bioactive glass (PBG-TiMg). The specimens underwent cycles of erosive challenge twice daily for 5 days with 1 mL of citric acid for 2 min followed by 1 mL of the suspension with bioactive substances for 3 min. After the cycles, profilometry, roughness and microhardness testing, and scanning electron microscopy (SEM) were performed. The following statistical tests were used: one-way ANOVA (profile, roughness, and surface microhardness (%VMS) data variation), Tukey's HSD (%VMS), Games-Howell test (profilometry), Student's t test (roughness), and Pearson's correlation between the variables. RESULTS: The lower loss of enamel surface and lower %VMS was observed in the PBG-Mg and PBG-TiMg groups, and only the PBG-Mg group showed similar roughness between baseline and eroded areas (p > 0.05). On SEM micrographs, PBG-Ti and PBG-Mg groups showed lower apparent demineralization. CONCLUSION: All bioactive materials protected the enamel against erosion. However, strontium-containing phosphate bioactive glasses showed lower enamel loss, and the presence of Mg in these bioactive glasses provided a greater protective effect. CLINICAL RELEVANCE: Experimental strontium-containing phosphate bioactive glasses are effective in controlling enamel erosion. The results obtained in this study will guide the development of new dental products.


Asunto(s)
Óxido de Magnesio , Erosión de los Dientes , Esmalte Dental , Vidrio , Humanos , Fosfatos , Estroncio , Titanio , Erosión de los Dientes/prevención & control
6.
Ann Vasc Surg ; 72: 666.e7-666.e11, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33227481

RESUMEN

Splenic artery aneurysms (SAA) are more frequent in women and have a high rupture risk during pregnancy, with catastrophic outcomes. It is advisable to treat these aneurysms in pregnant and fertile women, whatever their diameter, given their increased risk for rupture. There are several therapeutic approaches: endovascular surgery using coil embolization or stent graft coverage; laparoscopic or open surgical resection with arterial reconstruction and ligation followed by splenectomy when necessary. This paper aims to report the successful treatment of SAA in second-trimester pregnant women using a laparoscopic approach with aneurysm resection and arterial reconstruction. This is a unique report of a minimally invasive approach with arterial reconstruction in a pregnant woman, thus reducing the risk of spleen infarction and potentially avoiding splenectomy.


Asunto(s)
Aneurisma/cirugía , Laparoscopía , Procedimientos de Cirugía Plástica , Complicaciones Cardiovasculares del Embarazo/cirugía , Arteria Esplénica/cirugía , Técnicas de Sutura , Adulto , Anastomosis Quirúrgica , Aneurisma/diagnóstico por imagen , Femenino , Humanos , Embarazo , Complicaciones Cardiovasculares del Embarazo/diagnóstico por imagen , Segundo Trimestre del Embarazo , Arteria Esplénica/diagnóstico por imagen , Resultado del Tratamiento
7.
Am J Dent ; 34(3): 171-176, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34143589

RESUMEN

PURPOSE: To evaluate the stress distribution of inlays fabricated with restorative materials of different elastic moduli under two functional loading conditions by using three-dimensional (3D) finite element analysis (FEA) models of a second maxillary premolar. METHODS: A 3D model of a sound maxillary left second premolar and its supporting bone was generated in a previous study and reutilized under permission of the authors for the present study. Inlay models obtained from the sound tooth were then assigned according to the type and inherent elastic modulus of the restorative material used, as follows: microhybrid composite (Filtek Z250); indirect resin composite (Paradigm); lithium disilicate reinforced glass ceramic (IPS e.max Press); and type III gold alloy. The geometric models were then exported for 3D FEA. All materials were considered isotropic, homogeneous, and linear-elastic. A static load of 100 N was applied in two conditions: axially at both cusps (axial loading) and at the mesial marginal ridge (proximal loading). Maximum principal and von Mises stresses were used to analyze the stress distribution pattern in inlays and sound premolar models. RESULTS: Under axial loading condition, either resin composite, ceramic or type III gold alloy inlays generated a similar biomechanical behavior, especially in terms of stress distribution in the remaining tooth structure and cusp deflection. However, higher tensile stresses were observed along the proximal gingival margin of the preparation under proximal loading in the Z250 and Paradigm models, as well as a greater cusp deflection. In contrast, a deflection like the sound model was observed in the ceramic and gold inlay models. CLINICAL SIGNIFICANCE: Restorative materials with higher elastic modulus, such as dental ceramics and type III gold alloys, seem to be the best choice for maxillary premolars restored with inlays in the presence of occlusal contact on the marginal ridge.


Asunto(s)
Porcelana Dental , Incrustaciones , Diente Premolar , Resinas Compuestas , Materiales Dentales , Análisis del Estrés Dental , Análisis de Elementos Finitos , Ensayo de Materiales , Estrés Mecánico
8.
J Invertebr Pathol ; 177: 107498, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33137318

RESUMEN

Despite the considerable number of genetic markers published for Penaeus vannamei, the classification of these markers and their standardization in specific databases is still insufficient. As a consequence, access to these markers is difficult, hampering their application in genetic association studies. In this study, all previously described single nucleotide polymorphisms (SNPs) related to resistance for P. vannamei were revised, and 512 SNPs were identified and classified in detail. We observed that most of the SNPs occurred in the proteins including Toll like receptors 1 and 3, hemocyanin large and small subunits, and anti-lipopolysaccharide factors 1 and 2, allowing to propose to use them as targets in association studies involving resistance in P. vannamei. Additionally, the potential effects of the most frequent non-synonymous coding SNPs in the secondary structure of the main target proteins were evaluated using an in silico approach. These data can serve as the starting point for the development of new genetic and computational tools as well as for the design of new association studies that involve resistance in P. vannamei.


Asunto(s)
Proteínas de Artrópodos/genética , Penaeidae/genética , Polimorfismo de Nucleótido Simple , Animales , Proteínas de Artrópodos/metabolismo , Penaeidae/microbiología , Penaeidae/parasitología , Penaeidae/virología
9.
J Mater Sci Mater Med ; 31(11): 94, 2020 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-33128627

RESUMEN

Titanium and titanium alloys are widely used as a biomaterial due to their mechanical strength, corrosion resistance, low elastic modulus, and excellent biocompatibility. TiO2 nanotubes have excellent bioactivity, stimulating the adhesion, proliferation of fibroblasts and adipose-derived stem cells, production of alkaline phosphatase by osteoblasts, platelets activation, growth of neural cells and adhesion, spreading, growth, and differentiation of rat bone marrow mesenchymal stem cells. In this study, we investigated the functionality of fibroblast on titania nanotube layers annealed at different temperatures. The titania nanotube layer was fabricated by potentiostatic anodization of titanium, then annealed at 300, 530, and 630 °C for 5 h. The resulting nanotube layer was characterized using SEM (Scanning Electron Microscopy), TF-XRD (Thin-film X-ray diffraction), and contact angle goniometry. Fibroblasts viability was determined by the CellTiter-Blue method and cytotoxicity by Lactate Dehydrogenase test, and the cell morphology was analyzed by scanning electron microscopy. Also, cell adherence, proliferation, and morphology were analyzed by fluorescence microscopy. The results indicate that the modification in nanotube crystallinity may provide a favorable surface fibroblast growth, especially on substrates annealed at 530 and 630 °C, indicating that these properties provide a favorable template for biomedical implants.


Asunto(s)
Fibroblastos/metabolismo , Nanotubos/química , Titanio/química , Animales , Materiales Biocompatibles/química , Células de la Médula Ósea/citología , Adhesión Celular , Diferenciación Celular/efectos de los fármacos , Proliferación Celular , Supervivencia Celular , Cristalización , Citoesqueleto/metabolismo , Células Madre Mesenquimatosas/citología , Microscopía Electrónica de Rastreo , Microscopía Fluorescente , Osteoblastos/citología , Prótesis e Implantes , Ratas , Células Madre/citología
10.
Pediatr Cardiol ; 41(1): 155-164, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31768578

RESUMEN

Tetralogy of Fallot (ToF) is the most prevalent cyanotic congenital heart disease. Genetic syndromes are present in up to one quarter of patients with this condition, leading to increased morbidity and mortality. Our aim in this work is to characterize our population, evaluate ToF based on the presence of genotype anomalies, and investigate early intervention predictors and outcomes. A retrospective study was performed on neonates with ToF born between August 1, 2008, and August 31, 2018, and admitted to a level III neonatal intensive care unit (NICU). Patients were categorized based on the presence of genotype anomalies and timing of intervention. Thirty-nine neonates were included. The overall mortality during the follow-up period was 5.1% (n = 2). Threatened preterm labor/preterm labor was more prevalent in patients with associated genotype anomalies (p = 0.015). Multivariate analysis showed an association between an abnormal amount of amniotic fluid and ToF with altered genotype, adjusted for smoking, maternal age, gestational age and birth weight [OR = 29.92, 95% CI (1.35-662.44), p = 0.032]. We also found an association between cesarean delivery and neonatal procedures (p = 0.006). Mortality was significantly higher in neonates who underwent early intervention (p = 0.038). Our results indicate that an abnormal amount of amniotic fluid is an independent predictive factor for ToF with genotype alterations. This finding could ultimately have an impact on both prenatal and neonatal counseling and management.


Asunto(s)
Genotipo , Tetralogía de Fallot/genética , Adulto , Peso al Nacer , Cesárea/efectos adversos , Femenino , Edad Gestacional , Humanos , Recién Nacido , Masculino , Trabajo de Parto Prematuro/genética , Polihidramnios/genética , Embarazo , Estudios Retrospectivos , Factores de Riesgo , Tetralogía de Fallot/mortalidad
11.
J Prosthet Dent ; 123(6): 829-838, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31590983

RESUMEN

STATEMENT OF PROBLEM: The biomechanical behavior of post-restored roots with an experimental fiber-reinforced composite resin is unknown. PURPOSE: The purpose of this in vitro study was to investigate the biomechanical behavior of an experimental composite resin (3-mm short glass fiber incorporated in methacrylate matrix with filler particles) used to produce the custom post itself or to reline fiber posts. MATERIAL AND METHODS: Four testing groups (n=10) were created according to the root restoration method: FG, commercially available fiber post; FG+RC, fiber post relined with conventional composite resin; FG+EXP, fiber post relined with the experimental composite resin; and EXP, a custom post made of experimental composite resin. A three-dimensional finite element linear elastic analysis was performed by using geometric representations of groups, and the results were analyzed by von Mises (σvM) and maximum principal stress criteria. In sequence, 40 bovine incisors were assigned to these groups and subjected to a fracture load test (Instron 5965; 0.5 mm/min), and the failure mode was determined. RESULTS: The EXP group showed more homogeneous stress distribution for σvM. ANOVA and the Tukey honestly significant difference (HSD) tests showed significant differences (P<.001) in fracture load (mean ±standard deviation; different superscript letters indicate statistical difference): FG+EXP (669.5 ±107.7)A; FG (620.7 ±59.2)A; EXP (506.5 ±27.0)B; FG+RC (452.7 ±81.6)B. No differences were found for failure mode (P=.595). CONCLUSIONS: The experimental composite resin significantly increases fracture load when used to reline commercially available fiber posts and, irrespective of its use, presented lower stress concentration.


Asunto(s)
Técnica de Perno Muñón , Fracturas de los Dientes , Diente no Vital , Animales , Bovinos , Resinas Compuestas , Materiales Dentales , Análisis del Estrés Dental , Vidrio , Incisivo , Ensayo de Materiales
12.
Prep Biochem Biotechnol ; 50(7): 655-663, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32068481

RESUMEN

The partitioning and purification of lectins from the crude extract of Cratylia mollis seeds (Cramoll 1,4) was investigated in aqueous two-phase systems (ATPS). A factorial design model (24) was used to evaluate the influence of polyethylene glycol (PEG) molar mass (1500-8000 g/mol), PEG concentration (12.5-17.5% w/w), phosphate (10-15% w/w) concentration, and pH (6-8) on the differential partitioning, purification factor, and yield of the lectin. Polymer and salt concentration were the most important variables affecting partition of lectin and used to find optimum purification factor by experimental Box-Behnken design together with the response surface methodology (RSM). ATPS showed best conditions composed by 13.9% PEG1500, 15.3% phosphate buffer at pH 6, which ensured purification factor of 4.70. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a single band of protein with 26.1 kDa. Furthermore, results demonstrated a thermostable lectin presenting activity until 60 °C and lost hemagglutinating activity at 80 °C. According to the obtained data it can be inferred that the ATPS optimization using RSM approach can be applied for recovery and purification of lectins.


Asunto(s)
Lectinas/química , Lectinas/aislamiento & purificación , Phaseolus/química , Extractos Vegetales/química , Electroforesis en Gel de Poliacrilamida , Hemaglutininas/química , Concentración de Iones de Hidrógeno , Fosfatos/química , Polietilenglicoles/química , Proteínas/química , Semillas/química , Espectrofotometría , Propiedades de Superficie , Temperatura
13.
J Mol Evol ; 87(1): 7-15, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30456441

RESUMEN

The definition of a genomic signature (GS) is "the total net response to selective pressure". Recent isolation and sequencing of naturally occurring organisms, hereby named entoorganisms, within Acanthamoeba polyphaga, raised the hypothesis of a common genomic signature despite their diverse and unrelated evolutionary origin. Widely accepted and implemented tests for GS detection are oligonucleotide relative frequencies (OnRF) and relative codon usage (RCU) surveys. A common pattern and strong correlations were unveiled from OnRFs among A. polyphaga's Mimivirus and virophage Sputnik. RCU showed a common A-T bias at third codon position. We expanded tests to the amoebal mitochondrial genome and amoeba-resistant bacteria, achieving strikingly coherent results to the aforementioned viral analyses. The GSs in these entoorganisms of diverse evolutionary origin are coevolutionarily conserved within an intracellular environment that provides sanctuary for species of ecological and biomedical relevance.


Asunto(s)
Acanthamoeba/genética , Coevolución Biológica/genética , Mimiviridae/genética , Amoeba/genética , Animales , Bacterias/genética , Codón/genética , Evolución Molecular , Genoma Viral , Genómica , Mitocondrias/genética , Parásitos/genética , Proteínas Virales/genética , Virófagos/genética
14.
Nutr Cancer ; 71(4): 615-623, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30362831

RESUMEN

Colorectal cancer (CRC) is the third most frequent malignancy worldwide. Coffee is the second most consumed drink in the globe and suggested to decrease the CRC risk. Here, we explored whether coffee, decaffeinated coffee, or caffeine impact on the development of colorectal carcinogenesis induced by the direct carcinogen N-methyl-N-nitro-N-nitrosoguanidine (MNNG) in rats. To this end, sixty-four young male Wistar rats were divided into eight groups of eight animals each. We analyzed the frequency of dysplastic crypts and expression of metallothionein as a biomarker of the cancer risk, as well the expression of phosphorylated H2A histone family/member X (γH2AX) for DNA damage and cyclooxygenase-2 (COX-2) for inflammatory response. We also studied the oxidative stress profile in hepatic and colonic frozen samples (malondialdehyde [MDA], glutathione [GSH], and α-tocopherol). We found that coffee but neither decaffeinated coffee nor caffeine decreased the development of dysplastic crypts in MNNG-exposed rats. All treatments reduced DNA damage intensity in colonocytes. Only decaffeinated coffee increased the numbers of metallothionein positive crypts in comparison with coffee-treated rats. Coffee and caffeine inhibited COX-2 expression in the colon. Both decaffeinated coffee and caffeine decreased hepatic α-tocopherol levels. We suggest that coffee may have other compounds that elicit greater chemoprotective effects than caffeine reducing the CRC risk.


Asunto(s)
Anticarcinógenos/farmacología , Cafeína/farmacología , Carcinógenos/toxicidad , Café , Neoplasias Colorrectales/prevención & control , Animales , Café/química , Colon/efectos de los fármacos , Colon/metabolismo , Colon/patología , Neoplasias Colorrectales/inducido químicamente , Ciclooxigenasa 2/metabolismo , Daño del ADN/efectos de los fármacos , Histonas/metabolismo , Masculino , Metalotioneína/metabolismo , Metilnitronitrosoguanidina/toxicidad , Estrés Oxidativo/efectos de los fármacos , Ratas Wistar , alfa-Tocoferol/metabolismo
15.
Mar Drugs ; 17(6)2019 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-31212795

RESUMEN

Heparin or highly sulfated heparan sulfate (HS) has been described in different invertebrates. In ascidians (Chordata-Tunicata), these glycosaminoglycans occur in intracellular granules of oocyte accessory cells and circulating basophil-like cells, resembling mammalian mast cells and basophils, respectively. HS is also a component of the basement membrane of different ascidian organs. We have analyzed an HS isolated from the internal organs of the ascidian Phallusia nigra, using solution 1H/13C NMR spectroscopy, which allowed us to identify and quantify the monosaccharides found in this glycosaminoglycan. A variety of α-glucosamine units with distinct degrees of sulfation and N-acetylation were revealed. The hexuronic acid units occur both as α-iduronic acid and ß-glucuronic acid, with variable sulfation at the 2-position. A peculiar structural aspect of the tunicate HS is the high content of 2-sulfated ß-glucuronic acid, which accounts for one-third of the total hexuronic acid units. Another distinct aspect of this HS is the occurrence of high content of N-acetylated α-glucosamine units bearing a sulfate group at position 6. The unique ascidian HS is a potent inhibitor of the binding of human colon adenocarcinoma cells to immobilized P-selectin, being 11-fold more potent than mammalian heparin, but almost ineffective as an anticoagulant. Thus, the components of the HS structure required to inhibit coagulation and binding of tumor cells to P-selectin are distinct. Our results also suggest that the regulation of the pathway involved in the biosynthesis of glycosaminoglycans suffered variations during the evolution of chordates.


Asunto(s)
Adenocarcinoma/metabolismo , Anticoagulantes/metabolismo , Neoplasias del Colon/metabolismo , Glucuronatos/metabolismo , Heparitina Sulfato/química , Heparitina Sulfato/metabolismo , Selectina-P/metabolismo , Urocordados/metabolismo , Animales , Anticoagulantes/química , Línea Celular Tumoral , Colon/metabolismo , Ácido Glucurónico/metabolismo , Glicosaminoglicanos/metabolismo , Heparina/metabolismo , Humanos
16.
Glycobiology ; 28(8): 565-579, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29796665

RESUMEN

Fucosylated chondroitin sulfates (FCSs) and sulfated fucans (SFs) are conspicuous components of the body wall of sea cucumbers (Holothuroidea). FCSs are composed of a central core of chondroitin sulfate (CS) decorated with branches of mono- or both mono- and disaccharides of α-fucose (FCS types I and II, respectively). FCSs type II have heterogeneous and irregularly distributed α-fucose branches; however, the novel FCS type II from Holothuria lentiginosa described herein via solution nuclear magnetic resonance has strikingly homogeneous α-fucose branches neatly distributed along its CS core. This FCS is built up of three distinct sequential units composed of the typical CS disaccharides of FCSs, rich in ß-galactosamine-4,6diS, decorated with branches of α-Fucp-2,4diS, α-Fucp-3,4diS or α-Fucp[1→3]α-Fucp-4S[1→ linked to the position 3- of the ß-glucuronic acid. Conformational analyses of these repetitive units revealed a fairly rigid structure despite of the high sulfate content of their α-fucose branches. We also determined the structure of the SF from H. lentiginosa as a repetitive tetrasaccharide sequence composed of →3]α-Fucp-2,4diS[1→3]α-Fucp[1→3]α-Fucp-2S[1→3]α-Fucp-2S[1→. Furthermore, we determined that the nonsulfated α-fucose units present in FCS type II did not interfere with their anticoagulant potencies and affinities to calcium. FCS is an autapomorphic molecular character of the class Holothuroidea and the composition of their α-fucose branches differs in a species-specific manner. Branches containing α-Fucp-2,4diS are the most common within the extant holothurians, being found in 90% of the FCSs characterized thus far.


Asunto(s)
Sulfatos de Condroitina/química , Fucosa/química , Holothuria/química , Animales , Conformación de Carbohidratos
17.
BMC Gastroenterol ; 18(1): 30, 2018 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-29466950

RESUMEN

BACKGROUND: Anal residual tumors are consensually identified within six months of chemoradiotherapy and represent a persistent lesion that may have prognostic value for overall survival. The aim of this study was to evaluate the association of HPV and HIV status, p16 expression level and TP53 mutations with the absence of residual tumors (local response) in Squamous Cell Carcinoma (SCC) of the anal canal after chemoradiotherapy. METHODS: We performed a study on 78 patients with SCC of the anal canal who submitted to chemoradiotherapy and were followed for a six-month period to identify the absence or presence of residual tumors. HPV DNA was identified by polymerase chain reaction and direct sequencing, HIV RNA was detected by TaqMan amplification, p16 expression was detected by western blotting, and the mutational analysis of TP53 was performed by direct sequencing; additionally, samples carrying mutations underwent fluorescent in sit hybridization. The evaluation of the tumor response to treatment was conducted six months after the conclusion of chemoradiotherapy. The following classifications were used to evaluate the outcomes: a) no response (presence of residual tumor) and b) complete response (absence of residual tumor). RESULTS: The significant variables associated with the absence of residual tumors were HPV positive, p16 overexpressed, wild-type TP53, female gender, and stages I and II. Only the presence of HPV was independently correlated with the clinical response; this variable increased the chances of a response within six months by 31-fold. CONCLUSIONS: The presence of HPV in tumor cells was correlated with the absence of a residual tumor. This correlation is valuable and can direct future therapeutic approaches in the anal canal.


Asunto(s)
Neoplasias del Ano/terapia , Carcinoma de Células Escamosas/terapia , Quimioradioterapia , ADN Viral/análisis , Genes p16 , Neoplasia Residual , Papillomaviridae/genética , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Ano/genética , Neoplasias del Ano/patología , Neoplasias del Ano/virología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/virología , Femenino , Expresión Génica , Genotipo , VIH/genética , Humanos , Masculino , Persona de Mediana Edad , Mutación , Estadificación de Neoplasias , Resultado del Tratamiento
18.
Ann Vasc Surg ; 49: 312.e5-312.e7, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29455011

RESUMEN

BACKGROUND: Celiac artery (CA) occlusions/stenosis is infrequently associated with liver ischemia due to its unique vascularization, where portal vein provides about 75% of liver's perfusion. Collateral flow from gastroduodenal artery also provides, in most cases, enough blood supply to prevent ischemic hepatitis. In cases where these collateral pathways are compromised, severe liver ischemia can occur. METHODS: We present a case of acute mesenteric ischemia following gastric surgery that was treated with a hybrid retrograde CA stenting. RESULTS: We report a case of a 72-year-old male, who underwent gastric surgery for gastric cancer. On fourth postoperative day, he presented with acute abdomen, and on laparotomy, a partial duodenal suture dehiscence was found and suture closed. Owing to worsening of patient's clinical condition, with associated ischemic hepatitis, 2 days later, a computed tomography angiography was performed that showed a superior mesenteric artery (SMA) occlusion at its origin with an associated, severe, ostial stenosis of the CA. On laparotomy, irreversible visceral ischemia was found, which led to total colectomy, resection of 50 cms of small bowel, and splenectomy. Liver ischemia was also confirmed. Femoral access was used to try to cannulate the CA and cross its stenosis, without success. Taking advantage of the open abdomen, we then opted to place a 5F sheath in the splenic artery stump. From this retrograde approach, stenosis traversal was easy, and the CA was ballooned and stented with reperfusion of almost all the liver. Despite these efforts, patient died because of multiorganic failure, 8 days later. CONCLUSIONS: Ischemic hepatitis is a rare but serious complication of CA/SMA occlusive disease. Its occurrence is at increased risk after surgeries, where collateral flow is compromised. The endovascular treatment is currently the preferred approach to treat visceral arteries occlusive disease; however, antegrade CA cannulation can be tricky, and in an open abdomen scenario, retrograde approach from the splenic artery can be an additional resource. This case demonstrates the flexibility of endovascular techniques and that they can provide useful solutions even during open surgery.


Asunto(s)
Arteria Celíaca , Procedimientos Endovasculares/instrumentación , Gastrectomía/efectos adversos , Isquemia Mesentérica/terapia , Oclusión Vascular Mesentérica/terapia , Stents , Neoplasias Gástricas/cirugía , Enfermedad Aguda , Anciano , Arteria Celíaca/diagnóstico por imagen , Arteria Celíaca/fisiopatología , Angiografía por Tomografía Computarizada , Procedimientos Endovasculares/métodos , Resultado Fatal , Humanos , Masculino , Isquemia Mesentérica/diagnóstico por imagen , Isquemia Mesentérica/etiología , Isquemia Mesentérica/fisiopatología , Oclusión Vascular Mesentérica/diagnóstico por imagen , Oclusión Vascular Mesentérica/etiología , Oclusión Vascular Mesentérica/fisiopatología , Insuficiencia Multiorgánica/etiología , Circulación Esplácnica , Resultado del Tratamiento
19.
Environ Monit Assess ; 190(9): 511, 2018 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-30097732

RESUMEN

The Serra do Mar State Park forms a green corridor that connects significant remnants of the Atlantic Forest in Brazil, a region that presents great biodiversity. However, the mounting pressure exerted on it by disorderly urban expansion around conservation unit areas is a cause for concern. Thereby, this paper aims to analyze a geographical and demographic characterization of Serra do Mar State Park and its buffer zone in order to identify regions under the greatest pressure and provide subsidies for developing public policies. The study is based on a cartographic representation using a geographic information system associated with the 2010 Census demographic data, which has been conducted by the Brazilian Institute of Geography and Statistics (IBGE in Portuguese acronym). The study area covers the territory of 32 municipalities and it was found that almost 25,000 inhabitants live inside the park while approximately 712,000 residents live inside its buffer zone.


Asunto(s)
Conservación de los Recursos Naturales , Demografía , Monitoreo del Ambiente , Animales , Biodiversidad , Brasil , Bosques , Sistemas de Información Geográfica , Geografía
20.
Glycobiology ; 27(7): 625-634, 2017 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28460072

RESUMEN

Fucosylated chondroitin sulfate (FCS) from sea cucumbers is composed of a chondroitin sulfate (CS) central core and branches of sulfated fucose. The structure of this complex glycosaminoglycan is usually investigated via nuclear magnetic resonance (NMR) analyses of the intact molecule, ergo through a top-down approach, which often yield spectra with intricate sets of signals. Here we employed a bottom-up approach to analyze the FCSs from the sea cucumbers Isostichopus badionotus and Ludwigothurea grisea from their basic constituents, viz. CS cores and sulfated fucose branches, obtained via systematic fragmentation through mild acid hydrolysis. Oligosaccharides derived from the central CS core were analyzed via NMR spectroscopy and the disaccharides produced using chondroitin sulfate lyase via SAX-HPLC. The CS cores from the two species were similar, showing only slight differences in the proportions of 4- or 6-monosulfated and 4,6-disulfated ß-d-GalNAc. Sulfated fucose units released from the FCSs were analyzed via NMR and ESI-HRMS spectroscopies. The fucose units from each species presented extensive qualitative differences, but quantitative assessments of these units were hindered, mostly because of their extensive desulfation during the hydrolysis. The bottom-up analysis performed here has proved useful to explore the structure of FCS through a sum-of-the-parts approach in a qualitative manner. We further demonstrate that under specific acidification conditions particular fucose branches can be removed preferentially from FCS. Preparation of derivatives enriched with particular fucose branches could be useful for studies on "structure vs. biological function" of FCS.


Asunto(s)
Sulfatos de Condroitina/química , Fucosa/análisis , Animales , Sulfatos de Condroitina/metabolismo , Espectroscopía de Resonancia Magnética , Pepinos de Mar/química , Pepinos de Mar/metabolismo , Espectrometría de Masa por Ionización de Electrospray
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