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1.
Retina ; 38(12): 2309-2316, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29016453

RESUMEN

PURPOSE: To analyze the performance and flow characteristics of novel double-cutting, open-port, 23-, 25-, and 27-gauge ultrahigh-speed vitrectomy systems. METHODS: In vitro fluidic measurements were performed to assess the volumetric aspiration profiles of several vitrectomy systems in basic salt solution and egg white. RESULTS: Double-cutting open-port vitrectomy probes delivered stable aspiration flow rates that were less prone to flow variation affected by the cutting speed. Increase in cutting frequency to the maximum level resulted in flow reduction of less than 10% (0.0%-9.5%). Commercially available 23-, 25-, and 27-G double-cutting probes exhibited higher egg-white and basic salt solution flow rates at all evaluated cut rates, with aspirational efficiencies being 1.1 to 2.9 times the flow rates of standard single-blade vitrectomy probes of the same caliber at the maximum preset vacuum. The highest relative differences were observed at faster cut rates. CONCLUSION: The newly introduced double-cutting open-port vitrectomy probes delivered stable aspiration flow rates that were less prone to flow variation affected by the cutting speed. The fluidic principle of constant flow even at the highest cut rates and low vacuum levels might impact surgical strategies, especially when performing manipulations close to the retina.


Asunto(s)
Modelos Biológicos , Vitrectomía/instrumentación , Cuerpo Vítreo/cirugía , Diseño de Equipo , Humanos , Cinética , Microcirugia/instrumentación , Grabación en Video
2.
J Phycol ; 51(6): 1055-65, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26987001

RESUMEN

The calcifying Conjugatophyte Oocardium stratum occurs exclusively in spring-associated limestones (SAL) with active meteogene limestone deposition. The macroscopic colonies of Oocardium stratum form hemispherical, pinhead-like structures with a diameter of 0.5-2.0 mm. As its autecology is still poorly understood, we focused on the seasonal development of Oocardium stratum and linked environmental factors to its abundance. The study was conducted in a rivulet in Lunz/See (Austria) for 16 months on a weekly (growing season) to monthly (winter season) basis. Oocardium colonies were found throughout the whole year, with maximum abundance during the mid-summer months July and August. Repeated macro-mapping of three SAL sites measuring 750 cm(2) each showed a maximum Oocardium cover of around 30% in August; two smaller peaks developed in early summer and late autumn with ~10% cover. Diatom mats dominated by Cymbella excisiformis occurred in spring, autumn and winter, with more than 75% cover. The seasonal change between Oocardium and diatoms in limestone-precipitating springs causes a typical sequence pattern of limestone layers. Redundancy analysis revealed water temperature and bicarbonate content as the main structuring factors; these control the occurrence and growth of Oocardium, reflecting season as a background variable. Optimum growth conditions for Oocardium were an alkalinity around 4.7 meq · L(-1) and a water temperature around 13°C. Site openness, nitrate and dissolved carbon dioxide were inversely related to Oocardium biomass, the opposite for diatoms. Other environmental factors such as total ions or soluble reactive phosphorus had no significant influence on Oocardium stratum abundance.

3.
Sci Total Environ ; 854: 158814, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36115411

RESUMEN

Pesticide drift onto non-agricultural land is a common problem in intensively farmed regions, and national action plans have been established across Europe to prevent it. Here, we analyzed official data on pesticide residues in grass samples collected over six years to determine whether implemented measures to reduce pesticide drift were effective. We used 306 samples collected between 2014 and 2020 on non-agricultural land in one of the most intensively managed apple and wine growing regions in Europe, the Autonomous Province of Bolzano-South Tyrol, Italy. Samples were analyzed for up to 314 substances by gas chromatography and mass spectrometry. Percentage of sites with multiple pesticides and number of pesticides decreased between 2014 and 2020. Fungicides were most often detected, with fluazinam found on 74 % and captan on 60 % of the contaminated sites (53 sites out of a total of 88 sites were contaminated). The most frequently found insecticide, phosmet, was detected in 49 % of the contaminated sites. Only one herbicide, oxadiazon, was detected in <1 % of the sites; glyphosate was not analyzed. The percentage of residues with human hazard properties increased significantly across years regarding reproductive toxicity (from 21 % of the detected substances in 2014 to 88 % in 2020) and specific target organ toxicity (0 % in 2014 to 21 % in 2020). Percentages of substances associated with endocrine-disruption (89 % of substances across years) or carcinogenic properties (45 % of substances across years) remained constant. The percentage of sites where concentrations in grass samples exceeded the surrogate maximum residue levels (MRLs) for lettuce also remained constant. Potential ecotoxicological hazards of detected residues regarding acute contact toxicity to honeybees remained high over the study years, while the acute and chronic toxicity to earthworms decreased. Our results suggest that while drift mitigation measures contributed some reduction in pesticide contamination, they were not sufficient to eliminate substantial risks to human health and the environment in nontarget areas.


Asunto(s)
Fungicidas Industriales , Residuos de Plaguicidas , Plaguicidas , Humanos , Animales , Abejas , Plaguicidas/análisis , Cromatografía de Gases y Espectrometría de Masas , Residuos de Plaguicidas/análisis , Fungicidas Industriales/análisis , Europa (Continente)
4.
Health Econ ; 21 Suppl 2: 77-88, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22815114

RESUMEN

We analyse variations in cost or length of stay (LoS) for 66,587 patients from 10 European countries receiving a coronary artery bypass graft (CABG) procedure. In five of these countries, variations in cost are analysed using log-linear models. In the other five countries, negative binomial regression models are used to explore variations in LoS. We compare how well each country's diagnosis-related group (DRG) system and a set of patient-level characteristics explain these variations. The most important explanatory factors are the total number of diagnoses and procedures, although no clear effects are evident for our CABG-specific diagnostic and procedural variables. Wound infections significantly increase LoS and costs in most countries. There is no evidence that countries using larger numbers of DRGs to group CABG patients are better at explaining variations in cost or LoS. However, refinements to the construction of DRGs to group CABG patients might recognise first and subsequent CABGs or other specific surgical procedures, such as multiple valve repair.


Asunto(s)
Puente de Arteria Coronaria/economía , Grupos Diagnósticos Relacionados/estadística & datos numéricos , Costos de Hospital/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Factores de Edad , Comorbilidad , Puente de Arteria Coronaria/efectos adversos , Puente de Arteria Coronaria/estadística & datos numéricos , Europa (Continente) , Humanos , Tiempo de Internación/economía , Modelos Económicos , Complicaciones Posoperatorias/economía , Factores Sexuales
5.
J Trace Elem Med Biol ; 66: 126762, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33887692

RESUMEN

BACKGROUND: Aluminium salts are the most common adjuvants in infant vaccines. The aluminium content of a vaccine is provided by the manufacturer and is indicated on the patient information leaflet. There is no independent verification, for example by the European Medicines Agency, of the aluminium content of infant vaccines. METHODS: We have measured the aluminium content of thirteen infant vaccines using microwave-assisted acid and peroxide digestion followed by transversely heated graphite furnace atomic absorption spectrometry. Our data are compared with manufacturer's data using full statistical analyses including Bayesian methods. RESULTS: We found that only three vaccines contained the amount of aluminium indicated by the manufacturer. Six vaccines contained a statistically significant (P < 0.05) greater quantity while four vaccines contained a statistically significant (P < 0.05) lower quantity. The range of content for any single vaccine varied considerably, for example, from 0.172 to 0.602 mg/vaccine for Havrix. CONCLUSIONS: The data have raised specific questions about the significance of the aluminium content of vaccines and identified areas of extremely limited information. Since aluminium is a known toxin in humans and specifically a neurotoxin, its content in vaccines should be accurate and independently monitored to ensure both efficacy and safety.


Asunto(s)
Aluminio/análisis , Teorema de Bayes , Vacunas/química , Aluminio/metabolismo , Humanos , Lactante , Vacunas/metabolismo
6.
J Alzheimers Dis ; 73(4): 1627-1635, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31958088

RESUMEN

Genetic predispositions associated with metabolism of the amyloid-ß protein precursor underlie familial Alzheimer's disease; a form of dementia characterized by early disease onset and elevated levels of cortical amyloid-ß. Human exposure to aluminum is linked to the etiology of Alzheimer's disease and recent research measured a high content of aluminum in brain tissue in familial Alzheimer's disease. To elaborate upon this finding, we have obtained brain tissues from a Colombian cohort of donors with familial Alzheimer's disease. We have used established methods to measure the aluminum content of these tissues and we have compared the data with a recently measured dataset for control brain tissues. We report significantly higher levels of aluminum in brain tissues in donors with familial Alzheimer's disease than in control tissues from donors without neurological impairment or neurodegeneration. We have used aluminum-specific fluorescence microscopy along with complementary imaging for amyloid-ß to demonstrate a very high degree of co-localization of these two risk factors in brain tissue in familial Alzheimer's disease. Aluminum and amyloid-ß were co-located in senile plaques as well as vasculature, the latter resembling cerebral amyloid angiopathy. Aluminum was also found separately from amyloid-ß in intracellular compartments including glia and neuronal axons. The research has identified an arguably unique association between high brain aluminum content and amyloid-ß and allows postulation that genetic predispositions defining familial Alzheimer's disease underlie this relationship.


Asunto(s)
Aluminio/metabolismo , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Enfermedad de Alzheimer/genética , Axones/metabolismo , Química Encefálica , Angiopatía Amiloide Cerebral/metabolismo , Estudios de Cohortes , Colombia , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Microscopía Fluorescente , Persona de Mediana Edad , Neuroglía/metabolismo , Placa Amiloide/metabolismo , Factores de Riesgo
7.
Foot Ankle Int ; 39(2): 180-188, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29073780

RESUMEN

BACKGROUND: Hallux valgus surgery is associated with significant early postoperative pain. The aim of this study was to investigate the use of continuous wound infiltration (CWI) with ropivacaine for pain management after hallux valgus surgery. METHODS: In this prospective, randomized, double-blind, and placebo-controlled single-center trial, 50 patients undergoing distal metatarsal osteotomy for idiopathic hallux valgus were allocated to CWI with ropivacaine 2 mg/mL at a rate of 2 mL/h or placebo for 24 hours postoperatively. Average and peak pain levels on the verbal numeric rating scale (NRS; 1-10) during the first 48 hours after surgery were recorded as primary outcome parameters. Secondary outcome parameters included consumption of narcotics, clinical outcome, incidence of postoperative complications, and patient satisfaction. RESULTS: No significant difference in mean ( P = .596) and peak ( P = .353) postoperative pain level was found for CWI with either ropivacaine (mean NRS 1.9 ± 0.8; peak NRS 3.5 ± 2.0) or placebo (mean NRS 2.0 ± 0.7; peak NRS 3.9 ± 1.7) during the early postoperative course. Furthermore, no significant difference between both groups was detected regarding narcotic consumption ( P = .354) and all other secondary outcome parameters. Two severe complications (local dysesthesia with CWI, catheter accidentally fixed by a suture) and 5 catheter dislocations were observed. CONCLUSION: CWI with ropivacaine 2 mg/mL at a rate of 2 mL/h for 24 hours after hallux valgus surgery did not reduce postoperative pain level in an inpatient setting. LEVEL OF EVIDENCE: Level I, prospective randomized trial.


Asunto(s)
Amidas/farmacocinética , Juanete/complicaciones , Hallux Valgus/cirugía , Osteotomía/efectos adversos , Dolor Postoperatorio/etiología , Amidas/química , Amidas/farmacología , Método Doble Ciego , Humanos , Estudios Prospectivos , Ropivacaína
8.
Ann Intensive Care ; 8(1): 111, 2018 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-30446841

RESUMEN

BACKGROUND: Sepsis is associated with a deflection of inflammatory and coagulative parameters, since some clotting factors are known to be involved in the host's defense against infection and inflammation. These parameters could play a crucial role in the course of sepsis and be used as prognostic markers in critically ill children. METHODS: A total of 250 critically ill pediatric patients diagnosed with sepsis were retrospectively analyzed to identify routinely measured predictors for in-hospital mortality at the peak level of C-reactive protein. Those parameters entered multivariate logistic regression analysis as well as a decision tree for survival. RESULTS: Multivariate logistic regression analysis revealed fibrinogen, platelets and activated partial thromboplastin time (aPTT) at the peak level of C-reactive protein to be predictors for survival (p = 0.03, p = 0.01 and p = 0.02, respectively). An increase in fibrinogen and platelets is linked to survival, whereas an aPTT prolongation is associated with higher mortality; adjusted odds ratios (95% CI) for an increase of 100 mg/dl in fibrinogen are 1.35 (1.04-1.82) per 50 G/l platelets 1.94 (1.3-3.29) and 0.83 (0.69-0.96) for an aPTT prolongation of 10 s. Decision tree analysis shows that a fibrinogen level below 192 mg/dl (90.9% vs. 13% mortality) is most distinctive in non-survivors. CONCLUSIONS: High levels of fibrinogen and platelets as well as a non-overshooting aPTT are associated with a higher survival rate in pediatric patients with diagnosed sepsis. In particular, hypofibrinogenemia is distinctive for a high mortality rate in septic critically ill children.

9.
Artículo en Inglés | MEDLINE | ID: mdl-30126209

RESUMEN

Multiple sclerosis (MS) is a devastating and debilitating neurodegenerative disease of unknown cause. A consensus suggests the involvement of both genetic and environmental factors of which the latter may involve human exposure to aluminium. There are no data on the content and distribution of aluminium in human brain tissue in MS. The aluminium content of brain tissue from 14 donors with a diagnosis of MS was determined by transversely heated graphite furnace atomic absorption spectrometry. The location of aluminium in the brain tissue of two donors was investigated by aluminium-specific fluorescence microscopy. The aluminium content of brain tissue in MS was universally high with many tissues bearing concentrations in excess of 10 µg/g dry wt. (10 ppm) and some exceeding 50 ppm. There were no statistically significant relationships between brain lobes, donor age or donor gender. Aluminium-specific fluorescence successfully identified aluminium in brain tissue in both intracellular and extracellular locations. The association of aluminium with corpora amylacea suggests a role for aluminium in neurodegeneration in MS.


Asunto(s)
Aluminio/análisis , Química Encefálica , Esclerosis Múltiple/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Microscopía Fluorescente , Persona de Mediana Edad , Espectrofotometría Atómica
10.
EBioMedicine ; 26: 60-67, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29128442

RESUMEN

BACKGROUND: Progressive multiple sclerosis is a chronic autoimmune condition of unknown aetiology and few therapeutic options. Human exposure to aluminium has been linked with multiple sclerosis and affected individuals are known to excrete unusually high amounts of aluminium in their urine. Silicon-rich mineral waters facilitate the removal of aluminium from the body in urine and herein we have tested their efficacy in affecting urinary excretion of aluminium in individuals diagnosed with secondary progressive multiple sclerosis (SPMS). METHODS: Urinary excretion of aluminium and silicon, measured using transversely-heated graphite furnace atomic absorption spectrometry, was determined in 15 individuals diagnosed with SPMS over 24weeks, a 12week baseline period (control) followed by a 12week treatment period, during which individuals consumed up to 1.5L of a silicon-rich mineral water every day. FINDINGS: Individuals with SPMS excreted high amounts of aluminium during the baseline period (135.2nmol/mmol Crt (70.3-222.2, n=180) and females excreted significantly more aluminium than males. Regular drinking of a silicon-rich mineral water increased the urinary excretion of aluminium significantly (349.0nmol/mmol Crt (231.7-524.7, n=180; three-way ANOVA, F1,13=59.17, p-value=0.000003) relative to the baseline period. The majority of individuals, 14 out of 15, excreted more aluminium (µmol/24h) following drinking of a silicon-rich mineral water (independent-test, p<0.05). Silicon-rich mineral waters may be an effective and non-invasive therapy for the removal of aluminium from the body of individuals with SPMS.


Asunto(s)
Aluminio/orina , Aguas Minerales/uso terapéutico , Esclerosis Múltiple Crónica Progresiva/orina , Silicio/orina , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple Crónica Progresiva/dietoterapia , Esclerosis Múltiple Crónica Progresiva/fisiopatología , Espectrofotometría Atómica
11.
J Alzheimers Dis ; 57(2): 493-504, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28269764

RESUMEN

Alzheimer's disease (AD) is a progressive neurodegenerative disorder of the central nervous system. The use of biological fluids in AD diagnosis remains limited to the analysis of specific protein biomarkers in cerebrospinal fluid. However, metabolomic analysis has recently revealed several metabolites in plasma, especially phosphatidylcholines (PC), as putative biomarkers specific for AD. Following on previous reports of platelet abnormalities in AD, we hypothesized that platelets metabolites released in plasma may offer new biomarkers in AD. The aim of the present study was to apply targeted metabolomics to compare metabolites in soluble lysates of platelets from healthy controls (CO), patients with mild cognitive impairment (MCI), and patients with AD in a cohort of 90 subjects. We could target 163 metabolites and quantitative data were obtained for 91 metabolites. Among these, the lipid PC aeC40:4 significantly differentiated AD from CO (p = 0.0009), while four other lipids (PC aaC32:0, PC ae C32:2, PC aeC34:1, and SM(OH)C14:1) differentiated patients with MCI from CO. The combination of three phosphatidylcholines (PC aeC32:2, PC aeC34:1, PCaaC36:5), two lyso-phosphatidylcholines (lysoPC aC18:1, lysoPC aC16:0), and one sphingomyelin (SM(OH) C14:1) constructed a valuable prediction model using the C4.5 decision tree. The diagnosis accuracy for AD versus CO and MCI was 85%. In a blinded follow up conversion study (10 patients with a second blood collection after 9 months), we could verify the clinical diagnosis in 19 out of 20 cases. We propose that soluble platelet PCaeC40:4 is a promising marker to diagnose AD with a cut-off of <0.30µM and that platelets undergo metabolic processes during AD progression.


Asunto(s)
Enfermedad de Alzheimer/sangre , Disfunción Cognitiva/sangre , Metaboloma , Anciano , Enfermedad de Alzheimer/clasificación , Plaquetas/metabolismo , Disfunción Cognitiva/clasificación , Árboles de Decisión , Femenino , Estudios de Seguimiento , Humanos , Masculino , Pruebas de Estado Mental y Demencia , Metabolómica , Fosfatidilcolinas/sangre , Método Simple Ciego , Esfingomielinas/sangre
12.
EBioMedicine ; 21: 79-85, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28629908

RESUMEN

BACKGROUND: Previous studies on breast cancer (BC), underarm cosmetic products (UCP) and aluminum salts have shown conflicting results. We conducted a 1:1 age-matched case-control study to investigate the risk for BC in relation to self-reported UCP application. METHODS: Self-reported history of UCP use was compared between 209 female BC patients (cases) and 209 healthy controls. Aluminum concentration in breast tissue was measured in 100 cases and 52 controls. Multivariable conditional logistic regression analysis was performed to estimate odds ratios (ORs) with 95% confidence intervals (CIs), adjusting for established BC risk factors. FINDINGS: Use of UCP was significantly associated with risk of BC (p=0.036). The risk for BC increased by an OR of 3.88 (95% CI 1.03-14.66) in women who reported using UCP's several times daily starting at an age earlier than 30years. Aluminum in breast tissue was found in both cases and controls and was significantly associated to self-reported UCP use (p=0.009). Median (interquartile) aluminum concentrations were significantly higher (p=0.001) in cases than in controls (5.8, 2.3-12.9 versus 3.8, 2.5-5.8nmol/g). INTERPRETATION: Frequent use of UCPs may lead to an accumulation of aluminum in breast tissue. More than daily use of UCPs at younger ages may increase the risk of BC.


Asunto(s)
Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Cosméticos/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Aluminio/química , Estudios de Casos y Controles , Cosméticos/química , Femenino , Humanos , Persona de Mediana Edad , Oportunidad Relativa , Riesgo , Adulto Joven
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