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1.
Eur J Appl Physiol ; 123(8): 1825-1836, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37071199

RESUMEN

PURPOSE: During alternate movements across a joint, the changeover from one direction of rotation to the opposite may be influenced by the delay and rate of tension reduction and the compliance to re-lengthening of the previously active muscle group. Given the aging process may affect the above-mentioned factors, this work aimed to compare the dynamics of both the ankle torque decline and muscle re-lengthening, mirrored by mechanomyogram (MMG), in the tibialis anterior because of its important role in gait. METHODS: During the relaxation phase, after a supramaximal 35 Hz stimulation applied at the superficial motor point, in 20 young (Y) and 20 old (O) subjects, the torque (T) and MMG dynamics characteristics were measured. RESULTS: The T and MMG analysis provided: (I) the beginning of the decay after cessation of stimulation (T: 22.51 ± 5.92 ms [Y] and 51.35 ± 15.21 ms [O]; MMG: 27.38 ± 6.93 ms [Y] and 61.41 ± 18.42 ms [O]); (II) the maximum rate of reduction (T: - 110.4 ± 45.56 Nm/s [Y] and - 52.72 ± 32.12 Nm/s [O]; MMG: - 24.47 ± 10.95 mm/s [Y] and - 13.76 ± 6.54 mm/s [O]); (III) the muscle compliance, measuring the MMG reduction of every 10% reduction of torque (bin 20-10%: 15.69 ± 7.5[Y] and 10.8 ± 3.3 [O]; bin 10-0%: 22.12 ± 10.3 [Y] and 17.58 ± 5.6 [O]). CONCLUSION: Muscle relaxation results are different in Y and O and can be monitored by a non-invasive method measuring physiological variables of torque and re-lengthening dynamics at the end of the electromechanical coupling previously induced by the neuromuscular stimulation.


Asunto(s)
Relajación Muscular , Músculo Esquelético , Humanos , Músculo Esquelético/fisiología , Relajación Muscular/fisiología , Fenómenos Mecánicos , Tobillo , Articulación del Tobillo , Contracción Muscular/fisiología , Electromiografía/métodos , Torque , Estimulación Eléctrica/métodos
2.
BMC Public Health ; 22(1): 1074, 2022 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-35641925

RESUMEN

BACKGROUND: Effective smoking cessation programs exist but are underutilized by smokers, especially by disadvantaged smokers. Cessation interventions in dental settings have been shown to be effective, but are not consistently delivered due to provider burden and lack of training, especially on how to counsel smokers who are not motivated to quit. METHODS: This study is a 2-arm, phase III longitudinal randomized controlled efficacy trial to motivate utilization of evidenced based treatments (EBTs) for smoking cessation (e.g., state quitline, clinic-based counseling, the National Cancer Institute's text message program, and pharmacotherapy). Patients attending an urban dental clinic (n = 376) will be randomized to an intervention group (INT; smoking cessation induction video delivered via VR headset during their teeth cleaning, brochure about EBTs, and a 4-week text message program) or control group (CTRL; relaxation video delivered via VR headset during teeth cleaning, the same brochure as INT, and assessment-only text messages). Assessments will occur at baseline, immediately after the clinic appointment, one-month post-appointment and 3-and 6 months later. We hypothesize INT will be more likely to contact EBTs vs CTRL and have greater utilization rates of EBTs. Secondary objectives are to test the efficacy of INT on point-prevalence smoking abstinence, quit smoking attempts, and motivation to quit vs. CTRL. DISCUSSION: Incorporating smoking cessation into a dental clinic visit and targeting all smokers, regardless of motivation to quit, provides proactive reach to cigarette smokers who otherwise may not seek treatment for smoking. TRIAL REGISTRATION: NCT04524533 Registered August 24, 2020.


Asunto(s)
Cese del Hábito de Fumar , Realidad Virtual , Terapia Conductista , Ensayos Clínicos Fase III como Asunto , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Fumadores , Fumar/psicología , Cese del Hábito de Fumar/métodos
3.
Community Dent Health ; 39(1): 33-39, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34862864

RESUMEN

BACKGROUND: In recent years, the consumption of sugar sweetened beverages has been declining, while low calorie sweetener and diet beverage consumption is increasing. Evidence about the effect of diet drinks on dental caries is insufficient, and has not accounted for the complexity of beverage consumption patterns. Therefore, the aim of this study is to examine the association between consuming diet drinks and dental caries among US adults. METHODS: We analyzed 2011-2014 NHANES dietary data of adults using cluster analysis, with individuals grouped based on their beverage consumption. Clusters were identified based on the R-square statistic and the local peak of the pseudo F statistic. Survey procedure and sample weights were used to account for the complex NHANES sampling design. RESULTS: Four beverage consumption patterns were identified: "high soda", "high diet drinks", "high coffee/tea" and "high water". The "High soda" cluster was the only one associated with higher DMFT after controlling for confounders (ß=1.02, 95% CI=0.42 - 1.63), whereas DT was associated with "high soda" (ß=0.45, 95% CI=0.25 - 0.64) and "high coffee/tea" (ß=0.24, 95% CI=0.01 - 0.47). On the other hand, the "high diet drinks" cluster was neither associated with DMFT (ß=0.69, 95% CI=0.51 - -0.35) nor DT (ß=0.07, 95% CI=-0.21 - 0.35). CONCLUSION: Diet drinks consumption may not be associated with increased risk of dental caries. However, more studies should be conducted in order to confirm this finding.


Asunto(s)
Bebidas Endulzadas Artificialmente , Caries Dental , Adulto , Bebidas/efectos adversos , Bebidas Gaseosas/efectos adversos , Análisis por Conglomerados , Caries Dental/epidemiología , Caries Dental/etiología , Dieta/efectos adversos , Humanos , Encuestas Nutricionales
4.
J Microencapsul ; 34(6): 560-570, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28805476

RESUMEN

The aim of this work was to obtain microencapsulated stable Aspergillus niger peptidases by post fermentation spray drying. The enzymatic extract was evaluated before and after spray drying microencapsulation to verify the effects of five different process parameters on the extract enzymatic activity, i.e. air flow, extract feed rate, drying temperature, homogenising time and weight ratio of extract to encapsulation material. The optimal conditions were determined by desirability functions and experimentally confirmed. Additionally, the stability of the microparticles was assessed during 60 days at 4 °C, 25 °C and 40 °C. The results revealed that the microparticles stored at 4 °C retained approximately 100% of their proteolytic activity at nine days of storage. Considering the industrial adaptation of the bioprocess and the prospect of commercial application of the proteases, the evaluation of different parameters for drying enzymes is required as a valuable alternative to obtain biotechnological products with high added value.


Asunto(s)
Aspergillus niger/enzimología , Fibras de la Dieta/metabolismo , Fermentación , Residuos Industriales , Péptido Hidrolasas/química , Composición de Medicamentos , Estabilidad de Enzimas
5.
J Fish Biol ; 89(1): 337-54, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27250698

RESUMEN

In this study data relative to the fishery in the freshwater area of the Patos Lagoon are analysed, and the dynamics, fishing gears used and catches evaluated. The results reveal the existence of two fishery strategies: forbidden mesh size gillnets (FMG; <35 mm; square measure) and allowed mesh size gillnets (AMG; ≥35 mm; square measure). In total, 31 species were caught (AMG = 27 and FMG = 24), but selectivity due to mesh size was significant (P < 0·001). The FMG may be very harmful since it captures individuals of most species below size at first maturity, including the target species, the armoured catfish Loricariichthys anus (61% of the total catch). In addition, this gear is used throughout the year, including the closed season (CS; November to January), when the target species is reproducing. Target species for the AMG are larger in size, comprising mainly the mullet Mugil liza, the marine catfish Genidens barbus and the whitemouth croaker Micropogonias furnieri. AMS gillnets were not used during the CS. The use of FMG reveals the need for effective fishery law enforcement and the need for additional studies to assess the status of populations of the exploited species.


Asunto(s)
Explotaciones Pesqueras/estadística & datos numéricos , Peces , Agua Dulce , Animales , Brasil , Bagres , Cultura , Explotaciones Pesqueras/legislación & jurisprudencia , Perciformes , Reproducción , Estaciones del Año , Smegmamorpha
6.
Braz J Microbiol ; 55(3): 2557-2568, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38954219

RESUMEN

Fusarium oxysporum is a cross-kingdom pathogen that infects humans, animals, and plants. The primary concern regarding this genus revolves around its resistance profile to multiple classes of antifungals, particularly azoles. However, the resistance mechanism employed by Fusarium spp. is not fully understood, thus necessitating further studies to enhance our understanding and to guide future research towards identifying new drug targets. Here, we employed an untargeted proteomic approach to assess the differentially expressed proteins in a soil isolate of Fusarium oxysporum URM7401 cultivated in the presence of amphotericin B and fluconazole. In response to antifungals, URM7401 activated diverse interconnected pathways, such as proteins involved in oxidative stress response, proteolysis, and lipid metabolism. Efflux proteins, antioxidative enzymes and M35 metallopeptidase were highly expressed under amphotericin B exposure. Antioxidant proteins acting on toxic lipids, along with proteins involved in lipid metabolism, were expressed during fluconazole exposure. In summary, this work describes the protein profile of a resistant Fusarium oxysporum soil isolate exposed to medical antifungals, paving the way for further targeted research and discovering new drug targets.


Asunto(s)
Anfotericina B , Antifúngicos , Fluconazol , Proteínas Fúngicas , Fusarium , Proteómica , Microbiología del Suelo , Fusarium/efectos de los fármacos , Fusarium/metabolismo , Fusarium/genética , Antifúngicos/farmacología , Antifúngicos/metabolismo , Fluconazol/farmacología , Anfotericina B/farmacología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Farmacorresistencia Fúngica , Pruebas de Sensibilidad Microbiana , Proteoma/análisis
7.
J Intern Med ; 273(5): 511-26, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23331508

RESUMEN

BACKGROUNDS: With increasing use of opioids for chronic noncancer pain comes concern about safety of this class of drugs. Opioid-induced hypogonadism, which could increase the risk for myocardial infarction (MI), has recently come to the attention of clinicians. To evaluate this concern we examined the association between opioid use for noncancer pain and risk of MI amongst adults. METHODS: We conducted a nested case-control study using the UK General Practice Research Database. Amongst 1.7 million opioid users during 1990-2008, we identified 11 693 incident MI cases aged 18-80 years, and randomly selected up to four controls matched by age, gender, index date (date of onset symptoms or diagnosis of first-ever MI) and general practice via risk-set sampling. Cases and controls were required to have no cancer and no major risk factors for MI before the index date. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated from conditional logistic regression. RESULTS: Compared with nonuse, current use of opioids was associated with a 1.28-fold (95% CI 1.19-1.37) risk of MI. Cumulative use of opioids with 11-50 (OR = 1.38, 95% CI: 1.28-1.49) or > 50 (OR = 1.25, 95% CI: 1.11-1.40) prescriptions, was also marginally associated with increased risk of MI. The risk was particularly increased in users of morphine (OR = 1.71, 95% CI: 1.09-2.68), meperidine (OR = 2.15, 95% CI: 1.24-3.74) and polytherapy (OR = 1.46, 95% CI: 1.22-1.76). CONCLUSIONS: Current use of any opioids and cumulative use of 11 or more prescriptions are associated with a small increased risk for MI compared to nonuse and the risk was greater in morphine, meperidine and polytherapy users. Residual confounding, particularly confounding by indication, should be considered in interpreting our results.


Asunto(s)
Analgésicos Opioides/efectos adversos , Infarto del Miocardio/inducido químicamente , Dolor/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Analgésicos Opioides/administración & dosificación , Estudios de Casos y Controles , Femenino , Humanos , Incidencia , Masculino , Sistemas de Registros Médicos Computarizados , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/epidemiología , Riesgo , Muestreo , Reino Unido/epidemiología
8.
Artículo en Inglés | MEDLINE | ID: mdl-23774589

RESUMEN

The influence of increasing temperatures in thermal and oxidative stress responses were studied in the muscle of several estuarine fish species (Diplodus vulgaris, Diplodus sargus, Dicentrarchus labrax, Gobius niger and Liza ramada). Selected fish were collected in July at the Tagus estuary (24±0.9°C; salinity of 30±4‰; pH=8). Fish were subjected to a temperature increase of 1°C.h(-1) until they reached their Critical Thermal Maximum (CTMax), starting at 24°C (control temperature). Muscle samples were collected during the trial and results showed that oxidative stress biomarkers are highly sensitive to temperature. Results from stress oxidative enzymes show alterations with increasing temperature in all tested species. Catalase (CAT; EC 1.11.1.6) activity significantly increased in L. ramada, D. labrax and decreased in D. vulgaris. Glutathione S-transferase (GST; EC 2.5.1.18) activity increased in L. ramada, D. sargus, D. vulgaris, and D. labrax. In G. niger it showed a cycle of increase-decrease. Lipid peroxidation (LPO) increased in L. ramada, D. sargus and D. labrax. With respect to correlation analysis (Pearson; Spearman r), the results showed that oxidation products and antioxidant defenses were correlated in L. ramada (LPO-CAT and LPO-GST, D. sargus (LPO-CAT), and D. labrax (LPO-CAT). Oxidative biomarkers were correlated with thermal stress biomarker (Hsp70) in L. ramada (CAT-Hsp70), D. vulgaris (LPO-Hsp70), D. labrax (GST-Hsp70) and G. niger (LPO-Hsp70). In conclusion, oxidative stress does occur with increasing temperatures and there seems to be a relation between thermal stress response and oxidative stress response. The results suggest that oxidative stress biomarkers should be applied with caution, particularly in field multi-species/multi-environment studies.


Asunto(s)
Peces/metabolismo , Respuesta al Choque Térmico , Músculo Esquelético/metabolismo , Estrés Oxidativo , Animales , Biomarcadores/metabolismo , Catalasa/metabolismo , Estuarios , Proteínas de Peces/metabolismo , Glutatión Transferasa/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Peroxidación de Lípido , Oxidación-Reducción
10.
Mar Pollut Bull ; 178: 113594, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35398691

RESUMEN

We used the Ecopath with Ecosim ecosystem model to assess the future effects of multiple stressors on sardine and the Portuguese continental shelf ecosystem. We assessed individual and combined impacts of changes in sardine fishing pressure, biomass of sardine competitors and predators and sea surface temperature (SST). This study demonstrated that the greatest impact on sardine stock is caused by projected SST rise whose effect is dominant and detrimental to sardine stock regardless of other conditions, including sardine fishing at maximum sustainable yield (FMSY). The largest impact on ecosystem stability, maturity and diversity of flows was observed under the forced-biomass scenarios that simulate changes in biomass of sardine predators and competitors. Moreover, these stressors alongside FMSY are projected to play an important role in the future evolution of the sardine stock. Results presented in this study can assist long-term and strategic management of the Iberian sardine stock.


Asunto(s)
Ecosistema , Caza , Biomasa , Portugal , Temperatura
11.
JDR Clin Trans Res ; 7(4): 425-434, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34622687

RESUMEN

OBJECTIVE: The aim of this study is to examine the effect of diet drinks on dental erosion among a representative sample of US adults. METHODS: Adult dietary and dental data were analyzed from the 2003-2004 cycle of the National Health and Nutrition Examination Survey. Erosion was measured with a modified tooth wear index and was analyzed as a dichotomous variable. Cluster analysis was performed, and the cluster number was based on having a separate diet drink cluster and the R2 values. Survey procedure and sample weights were used. RESULTS: Most of the population (80%) had some form of dental erosive lesions. When compared with the total sample, people with erosion were more likely to be male (52.5%) and older. People with no erosive lesions were younger (42.3%) and non-Hispanic Black (21.2%). Cluster analysis resulted in 4 distinct clusters: high water, high diet drinks, high coffee/tea, and high soda. The respective percentage of individuals in each cluster who had erosion was 78.9%, 85%, 83.9%, and 76.2%, where the "high diet drinks" cluster showed the highest erosion (P = 0.28). Logistic regression modeling showed that the "high diet drinks" cluster had increased odds of erosion (odds ratio = 1.27; 95% CI = 0.58 to 2.77) when compared with the "high water" cluster, but the relationship was not statistically significant. CONCLUSION: High diet drinks consumption slightly increased the odds of dental erosion among US adults, although this relationship was not statistically significant. It is thus not yet clear that dentists should recommend diet drinks, as they might be linked to systemic diseases. Further research is needed to explore more about risk factors of erosion. KNOWLEDGE TRANSFER STATEMENT: The findings of this study are suggestive, though not significantly, that diet drinks may increase risk for dental erosion. While further research is needed, it is not clear that dentists should recommend these drinks as healthy substitutes for sugary drinks.


Asunto(s)
Bebidas Endulzadas Artificialmente , Bebidas , Adulto , Bebidas/efectos adversos , Café , Dentición Permanente , Femenino , Humanos , Masculino , Encuestas Nutricionales , , Agua
12.
J Dent Res ; 101(8): 898-904, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35264049

RESUMEN

This retrospective analysis of longitudinal data was developed to determine which types, combinations, and intensities of topical fluorides more effectively prevent new caries-related restorations and extractions in high caries risk adults. We included data from October 1, 2008, through June 30, 2018, from electronic dental and medical records and pharmacy database from the US Department of Veterans Affairs. Veterans who were eligible for continuing and comprehensive care, met the criteria of high caries risk (received 2 or more caries-related restorations within a 365-d period), and had 3 y of follow-up were included. Multivariable logistic regression models estimated the odds of caries-related treatment during the 1-y observation period, controlling for age, gender, race and ethnicity, illness burden (Selim comorbidity index), use of prescription medications, attendance at dental prophylaxis appointments, number of caries-related restorations during the index year, and time between first and last caries-related restoration during the index year. The study sample included 68,757 veterans, who were primarily male (91.5%), were White (73.6%), had a mean age of 59.2 ± 13.5 y, and had significant medical comorbidity as measured by the Selim index (3.7 ± 2.4 physical and 1.3 ± 1.2 mental diagnoses). They had 10.8 ± 6.3 prescription VA drug classes, took 0.6 ± 0.8 strong anticholinergic medications, and had 3.9 ± 2.6 teeth restored due to caries during the index year. Adjusted multivariable logistic regression models showed veterans who received a varnish or gel/rinse fluoride intervention versus no fluoride had an approximately 29% decreased odds of receiving caries-related treatment during the observation period (gel/rinse adjusted odds ratio [AOR] = 0.72; 95% confidence interval [CI], 0.67-0.76; varnish AOR = 0.71; 95% CI, 0.67-0.75). The receipt of a varnish and gel/rinse did not demonstrate statistically better odds than each intervention alone (AOR = 0.69; 95% CI, 0.64-0.75). A dose-response effect was observed. Two-plus applications of varnish versus none (AOR = 0.73; 95% CI, 0.69-0.77) and 2-plus applications of gel/rinse versus none (AOR = 0.71; 95% CI, 0.67-0.75) were more effective than 1 application of either modality versus none.


Asunto(s)
Caries Dental , Fluoruros Tópicos , Adulto , Anciano , Cariostáticos/uso terapéutico , Caries Dental/epidemiología , Caries Dental/prevención & control , Susceptibilidad a Caries Dentarias , Fluoruros/uso terapéutico , Fluoruros Tópicos/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
13.
Parasitology ; 138(1): 107-21, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20819241

RESUMEN

The extent to which host biology, ecology and phylogeny determine the diversity of macroparasite assemblages has been investigated in recent years in several taxa, including fish. However, consensus has not been reached probably as a result of data being collected from different sources, different temporal scales or host and parasite biogeography and phylogeny having greater influence than expected. The present study evaluates the relative importance of 27 biological, ecological and phylogenetic characteristics of 14 flatfish species on the diversity of their ecto- and endoparasite assemblages, comprising a total of 53 taxa. Redundancy analyses were applied to the mean abundance of each parasite taxa infecting each host and to the richness, taxonomic distinctness and variance in taxonomic distinctness calculated for each assemblage within each host. Only a few host characteristics contributed significantly to the observed patterns: host distribution was more important in determining the type and mean abundance of ectoparasites present in an assemblage, whereas diversity of these assemblages were mainly related to the host's maximum size. Endoparasite mean abundance and diversity were mostly influenced by the number of food items ingested and by the presence of Crustacea and Polychaeta in the diet. However, the sympatric occurrence of related hosts also played an important role in the diversity values found in macroparasite assemblages. Results showed that a host characteristic has different importance according to the host-parasite relationship being examined, suggesting an important role for host-parasite co-evolution on the diversity of extant macroparasite assemblages.


Asunto(s)
Peces Planos/parasitología , Invertebrados/fisiología , Animales , Biodiversidad , Interacciones Huésped-Parásitos , Invertebrados/clasificación , Enfermedades Parasitarias en Animales , Filogenia , Densidad de Población , Portugal
14.
J Fish Biol ; 79(5): 1383-91, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22026615

RESUMEN

The diets of adult brill Scophthalmus rhombus and turbot Scophthalmus maximus from the Portuguese coast relied mostly on fishes. There was a higher diversity of food items compared to their northern counterparts, and several of the identified prey are the first records of these species, including a brown alga, echinoderms, nematodes, oligochaetes, gastropods, bivalves and various fish species. The diet of the two species was significantly different and niche overlap was low.


Asunto(s)
Dieta/veterinaria , Peces Planos/fisiología , Animales , Cadena Alimentaria , Contenido Digestivo , Portugal , Especificidad de la Especie
15.
Parasitology ; 137(11): 1671-80, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20500921

RESUMEN

SUMMARY: Macroparasites are generally aggregated within their hosts with infection and aggregation levels resulting from a continuous arms race between maintaining high mating probability and host mortality low for which host and environmentally related factors contribute to some extent. Here, infection and aggregation patterns of the macroendoparasites infecting the flatfish Citharus linguatula, Arnoglossus laterna, Lepidorhombus boscii, Scophthalmus rhombus and Platichthys flesus in 3 areas along the Portuguese coast were analysed. Of the 21 macroendoparasite species found only 1 infected all hosts and most were host or area exclusive. For each host-parasite system, values of the indices varied between areas and macroendoparasites were not always aggregated; in fact, some macroendoparasites were generally uniformly distributed, which can be related to specific density-dependent regulation mechanisms. No general pattern was found for infection or aggregation levels of the 3 species infecting more than 2 hosts along the Portuguese coast, i.e. Lecithochirium rufoviride, Nybelinia lingualis and Anisakis simplex s.l., suggesting that regulation mechanisms are not species specific but are locally determined, with host ecology playing a significant role.


Asunto(s)
Enfermedades de los Peces/parasitología , Peces Planos/parasitología , Helmintiasis Animal/parasitología , Interacciones Huésped-Parásitos , Nematodos/aislamiento & purificación , Filogenia , Platelmintos/aislamiento & purificación , Animales , Sistema Digestivo/parasitología , Ecosistema , Femenino , Enfermedades de los Peces/epidemiología , Peces Planos/clasificación , Peces Planos/genética , Helmintiasis Animal/epidemiología , Masculino , Nematodos/clasificación , Nematodos/patogenicidad , Platelmintos/clasificación , Platelmintos/patogenicidad , Densidad de Población , Portugal , Prevalencia , Especificidad de la Especie
16.
Protein Pept Lett ; 15(7): 724-30, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18782069

RESUMEN

Miliin, a new thiol-dependent serine protease purified from the latex of Euphorbia milii possesses a molecular weight of 79 kDa, an isoelectric point of 4.3 and is optimally active at 60 degrees C in the pH range of and 7.5-11.0. Activity tests indicate that milliin is a thiol-dependent serine protease.


Asunto(s)
Euphorbia/enzimología , Serina Endopeptidasas/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Concentración de Iones de Hidrógeno , Focalización Isoeléctrica , Punto Isoeléctrico , Cinética , Látex/química , Peso Molecular , Serina Endopeptidasas/química , Serina Endopeptidasas/metabolismo , Temperatura
17.
Mar Pollut Bull ; 56(10): 1728-36, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18768190

RESUMEN

The impact of dead discards, originating from beam trawl fishing on the nematode community from the Tagus estuary was investigated in terms of vertical distribution of the dominant nematode groups. Sediment cores were collected from a mud-flat from the Tagus estuary. Crangoncrangon (Linnaeus, 1758) carcasses were added to the surface of the cores, simulating the settling of dead discards on the sediment. The vertical distribution of the dominant nematode groups was determined up to 4cm deep at four different moments in time post deposition (0, 2, 4 and 6h) and compared to control cores. The C.crangon addition to the sediment led to the formation of black spots and therefore oxygen depleted areas at the sediment surface. The Chromadora/Ptycholaimellus group, normally dominant at the surface layer, migrated downwards due to their high sensibility to toxic conditions. Sabatieria presented the opposite trend and became the dominant group at the surface layer. Since Sabatieria is tolerant to oxygen stressed conditions and high sulphide concentrations, we suggest that it migrated opportunistically towards an unoccupied niche. Daptonema, Metachromadora and Terschellingia did not show any vertical migration, reflecting their tolerance to anoxic and high sulphidic conditions. Our study showed that an accumulation of dead discards at the sediment surface might therefore alter the nematode community vertical distribution. This effect is apparently closely related to toxic conditions in the sediment, induced by the deposition of C.crangon at the sediment surface. These alterations might be temporal and reflect an adaptation of the nematode community to dynamic intertidal environments.


Asunto(s)
Contaminantes Ambientales , Nematodos/fisiología , Animales , Monitoreo del Ambiente , Explotaciones Pesqueras , Sedimentos Geológicos , Océanos y Mares , Portugal , Ríos
18.
Mar Pollut Bull ; 56(11): 1834-43, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18790506

RESUMEN

The seasonal variation of five selected multimetric indices for the determination of the Ecological Quality Status (EQS) of transitional waters was evaluated, as well as the indices' responses to an extreme drought event that occurred in 2005. The database used regards the Mondego River estuary, which was sampled from June 2003 to August 2006 on a monthly basis. Among the selected indices (EBI-Deegan et al. [Deegan, L., Finn, J.T., Ayvazlan, S.G., Ryder-Kieffer, C.A., Buonaccoesi, J., 1997. Development and validation of an Estuarine Biotic Integrity Index. Estuaries 30(3), 601-617], EDI-Borja et al. [Borja, A., Franco, J., Valencia, V., Bald, J., Muxika, I., Belzunce, M.J., Solaun, O., 2004. Implementation of the European Water Framework Directive from the Basque Country (northern Spain): a methodological approach. Marine Pollution Bulletin 48(3-4), 209-218], EFCI-Harrison and Whitfield [Harrison, T.D., Whitfield, A.K., 2004. A multi-metric fish index to assess the environmental condition of estuaries. Journal of Fish Biology 65, 683-710], EBI-Breine et al. [Breine, J.J., Maes, J., Quataert, P., Van den Bergh, E., Simoens, I., Van Thuyne, G., Belpaire, C., 2007. A fish-based assessment tool for the ecological quality of the brackish Scheldt estuary in Flanders (Belgium). Hydrobiologia 575, 141-159] and TFCI - Coates et al. [Coates, S., Waugh, A., Anwar, A., Robson, M., 2007. Efficacy of a multi-metric fish index as an analysis tool for the transitional fish component of the Water Framework Directive. Marine Pollution Bulletin 55, 225-240]), the EBI by Breine et al. (2007) was the only that evidenced clear interannual and seasonal variations. The EQS by the several indices ranged from "Low" to "High", depending on the index considered, evidencing the high level of mismatch between indices. The results are discussed in the scope of the EU Water Framework Directive, regarding monitoring strategies, application of indices and EQS assessment.


Asunto(s)
Clima , Monitoreo del Ambiente/métodos , Peces/fisiología , Animales , Biodiversidad , Sequías , Monitoreo del Ambiente/normas , Biología Marina , Portugal
19.
Sci Total Environ ; 374(2-3): 199-215, 2007 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-17292947

RESUMEN

Estuaries are among the most productive ecosystems and simultaneously among the most threatened by conflicting human activities which damage their ecological functions, namely their nursery role for many fish species. A thorough assessment of the anthropogenic pressures in Portuguese estuarine systems (Douro, Ria de Aveiro, Mondego, Tejo, Sado, Mira, Ria Formosa and Guadiana) was made applying an aggregating multi-metric index, which quantitatively evaluates influences from key components: dams, population and industry, port activities and resource exploitation. Estuaries were ranked from most (Tejo) to least pressured (Mira), and the most influential types of pressure identified. In most estuaries overall pressure was generated by a dominant group of pressure components, with several systems being afflicted by similar problematic sources. An evaluation of the influence of anthropogenic pressures on the most important sparidae, soleidae, pleuronectidae, moronidae and clupeidae species that use these estuaries as nurseries was also performed. To consolidate information and promote management an ecological conceptual model was built to identify potential problems for the nursery function played by these estuaries, identifying pressure agents, ecological impacts and endpoints for the anthropogenic sources quantified in the assessment. This will be important baseline information to safeguard these vital areas, articulating information and forecasting the potential efficacy of future management options.


Asunto(s)
Conservación de los Recursos Naturales , Explotaciones Pesqueras , Modelos Teóricos , Animales , Ecosistema , Peces , Portugal , Análisis de Componente Principal , Agua de Mar
20.
Chem Sci ; 8(9): 6165-6170, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28989647

RESUMEN

Boronic acids are well known for their ability to reversibly interact with the diol groups found in sugars and glycoproteins. However, they are generally indiscriminate in their binding. Herein we describe the discovery of a group of heterocyclic boronic acids demonstrating unusually high affinity and selectivity for sialic acids (SAs or N-acetylneuraminic acid), which are sugar residues that are intimately linked with tumor growth and cancer progression. Remarkably, these interactions strengthen under the weakly acidic pH conditions associated with a hypoxic tumoral microenvironment. In vitro competitive binding assays uncovered a significantly higher ability of 5-boronopicolinic acid, one of the derivatives identified in this work as a strong SA-binder, to interact with cell surface SA in comparison to a gold-standard structure, 3-propionamidophenylboronic acid, which has proven to be an efficient SA-binder in numerous reports. This structure also proved to be suitable for further chemical conjugation with a well-preserved SA-binding capability. These findings suggest an attractive alternative to other ongoing boronic acid based chemistry techniques aiming to achieve tumor-specific chemotherapies and diagnoses.

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