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1.
Nature ; 593(7860): 548-552, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33882562

RESUMEN

Global peatlands store more carbon than is naturally present in the atmosphere1,2. However, many peatlands are under pressure from drainage-based agriculture, plantation development and fire, with the equivalent of around 3 per cent of all anthropogenic greenhouse gases emitted from drained peatland3-5. Efforts to curb such emissions are intensifying through the conservation of undrained peatlands and re-wetting of drained systems6. Here we report eddy covariance data for carbon dioxide from 16 locations and static chamber measurements for methane from 41 locations in the UK and Ireland. We combine these with published data from sites across all major peatland biomes. We find that the mean annual effective water table depth (WTDe; that is, the average depth of the aerated peat layer) overrides all other ecosystem- and management-related controls on greenhouse gas fluxes. We estimate that every 10 centimetres of reduction in WTDe could reduce the net warming impact of CO2 and CH4 emissions (100-year global warming potentials) by the equivalent of at least 3 tonnes of CO2 per hectare per year, until WTDe is less than 30 centimetres. Raising water levels further would continue to have a net cooling effect until WTDe is within 10 centimetres of the surface. Our results suggest that greenhouse gas emissions from peatlands drained for agriculture could be greatly reduced without necessarily halting their productive use. Halving WTDe in all drained agricultural peatlands, for example, could reduce emissions by the equivalent of over 1 per cent of global anthropogenic emissions.

2.
J Chem Phys ; 157(8): 084504, 2022 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-36049987

RESUMEN

Surface wetting phenomena impact chemistry, physics, biology, and engineering. The wetting behaviors of partially miscible binary liquid systems are especially complex. Here, we report evidence of universal behavior in the divergence of wetting layer growth at liquid-vapor interfaces of the cyclohexane + aniline, hexane + o-toluidine, and methanol + carbon disulfide systems. Layer growth on the micron scale was followed using visible light scattering from stirred samples. The layer thicknesses were found to diverge with decreasing temperature when coexistence was approached from the one-phase region, but only for solutions richer in the higher density/higher surface tension component. The onset of divergence was <1 K above the bulk coexistence temperature; nearer the critical composition, the onset temperature was the critical temperature itself. All three systems showed identical divergent wetting properties after variable normalization. In contrast, no divergent wetting layer formation was seen in the benzene + 1,2-propanediol or water + phenol systems. The mathematical sign of the Hamaker constant correlates with the contrasting behaviors. Collectively, these results have implications for theoretical descriptions of adsorption layer growth and crossover behavior, for measurements of complete wetting temperatures, and for practical applications.

3.
J Dairy Sci ; 105(3): 2453-2472, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35086708

RESUMEN

Intramammary infusion of antimicrobials at the end of lactation (dry cow therapy) has been a cornerstone of mastitis management for many years. However, as only a proportion of cows are infected at this time, treating only those cows likely to be infected is an important strategy to reduce antimicrobial usage and minimize risk of emergence of antimicrobial resistance. Such an approach requires the ability to discriminate between cows and quarters likely to be infected and uninfected. This study compared assignment of cows or quarters to antimicrobial treatment at the end of lactation based on cow composite somatic cell count (SCC; i.e., all quarters of cows with a maximum SCC across lactation >200,000 cells/mL received an antimicrobial; n = 891 cows, SCC-group) or assignment to quarter-level treatment based on a quarter level California Mastitis Test (CMT) score ≥ trace (n = 884 cows; CMT-group) performed immediately before drying off. All quarters of all cows also received an infusion of a bismuth-based internal teat sealant. Milk samples were collected for microbiology following the last milking, and again within 4 d of calving. Clinical mastitis records from dry off to 30 d into the subsequent lactation were collected. Multilevel, multivariable models were used to assess the effect of assignment to antimicrobial treatment. At drying off, a total of 575 (8.8%) and 147 (2.3%) of the 6,528 quarters had a minor, and a major intramammary infection (IMI), respectively. At drying off, 2089/3270 (63.9%) and 883/3311 (26.7%) of quarters were treated with dry cow therapy in the CMT and SCC-groups, respectively. Apparent bacteriological cure proportion for any IMI was higher in quarters assigned to the CMT than the SCC-group (349/368 (0.95, 95% CI 0.92-0.97) versus 313/346 (0.90, 95% CI 0.87-0.93)). New IMI proportion was lower among quarters assigned to the CMT than SCC-group [101/3,212 (0.032, 95% CI 0.025-0.038) versus 142/3,232 (0.044, 95% CI 0.036-0.051)]. The prevalence of any IMI postcalving was lower in quarters assigned to the CMT than SCC-group [119/3,243 (0.037, 95% CI: 0.030-0.044) versus 173/3,265 (0.054, 95% CI: 0.045-0.062)]. There was no difference in incidence of clinical mastitis between treatment groups. The total mass of antimicrobials used was 63% higher in the CMT-group than in the SCC-group (3.47 versus 2.12 mg/kg of liveweight). Selection of quarters for antimicrobial treatment at the end of lactation based on CMT resulted in greater proportion undergoing bacteriological cure, reduced risk of any new IMI and reduced post calving prevalence of any IMI compared with selection of cows based on SCC. However, CMT-based selection resulted in higher antimicrobial use compared with SCC-based selection, and further research is required to analyze the cost benefit and impact on risk of antimicrobial resistance of these 2 strategies.


Asunto(s)
Enfermedades de los Bovinos , Mastitis Bovina , Animales , Antibacterianos/farmacología , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Recuento de Células/veterinaria , Femenino , Lactancia , Glándulas Mamarias Animales/microbiología , Mastitis Bovina/microbiología , Leche/microbiología
4.
J Dairy Sci ; 105(9): 7513-7524, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35879166

RESUMEN

Adjusting end-of-milking criteria, in particular applying a maximum milking time determined by expected milk yield at an individual milking session, is one strategy to optimize parlor efficiency. However, this strategy can be difficult to apply practically on farm due to large differences in session milk yield, driven by milking interval, which affects milking routines and can be limited by in-parlor technology. The objective of this study was to test the hypothesis that a single fixed milking time (duration) could be applied at all milking sessions without compromising milk production or udder health for a range of milking intervals. To test the hypothesis, 4 experimental herds were established: (1) herd milked twice a day (TAD) using a 10- and 14-h interval, (2) herd milked TAD using an 8- and 16-h interval, (3) herd milked 3 times in 2 d using a 10-19-19-h interval, and (4) herd milked once a day (OAD). Herds consisted of 40 cows each, and were established for two 6-wk experimental periods, one in peak lactation and the other in mid-late lactation. Within each herd, half the cows had an end-of-milking criterion of 0.35 kg/min (Flow), and the other half had milking ended after a fixed period of time (FixedT) based on the average milking session yield, the daily milk yield divided by average number of milkings per day, irrespective of milking interval. We found no differences in daily milk yield between end-of-milking criteria due to residual milk from one milking likely increasing the proportion of milk in the udder cistern at the next milking session for the FixedT treatment. However, fat yield was compromised when the percentage of the herd with a truncated milking exceeded an estimated 33% at a milking session, which occurred in the TAD 8-16 herd due to the divergence from the average milking interval (in the case of TAD, 12-12 h). Applying a fixed milking time had no detrimental effects on udder health, except in the OAD herd in mid-late lactation, which had both a higher cell count and new intramammary infection rate. This warrants further investigation, although the majority of cultured bacteria were coagulase-negative staphylococci (CNS). Consequently, we conclude that, in general, with appropriate monitoring (e.g., weekly inspection) to ensure the proportion of the herd with truncated milkings does not exceed 33%, farmers in pasture-based dairy systems can use a fixed milking time to improve parlor efficiency.


Asunto(s)
Industria Lechera , Leche , Animales , Bovinos , Recuento de Células/veterinaria , Femenino , Lactancia , Glándulas Mamarias Animales
5.
N Z Vet J ; 70(2): 79-87, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34487486

RESUMEN

AIMS: To identify risk factors for subclinical and clinical mastitis in cows with low somatic cell counts (SCC) following infusion with internal teat sealant (ITS) at drying off. METHODS: Cows with no history of clinical mastitis and a maximum SCC <250,000 cells/mL at any herd test in the lactation before drying off were randomly selected from 36 herds. In the final week of lactation, quarter milk samples were collected aseptically from each selected cow for microbiology, and each quarter was then infused with ITS. Clinical mastitis records from 22 herds and herd test data from all herds were collated to determine potential herd- or cow-level explanatory variables for clinical mastitis over the dry period or in the first 60 days of the subsequent lactation, and subclinical mastitis (SCC >200,000 cells/mL; SCM) at the first herd test after calving. Multivariable, multilevel, logistic regression analyses were used to model the data. RESULTS: At drying off, 44/1,514 (2.8%) cows were infected with a major pathogen. Two of 1,001 (0.2%) cows were diagnosed with clinical mastitis over the dry period. There were 128/1,514 (8.5%) cows with SCM at the first herd test after calving. The odds of SCM were greater for cows with a major pathogen present at drying off than those without (OR = 4.7 (95% CI = 2.29-9.65); p < 0.001), and for third or greater lactation than second lactation cows (OR = 3.16 (95% CI = 1.70-5.88); p < 0.001). For every 1L increase in milk yield at the last herd test before drying off the OR for SCM was 1.07 (95% CI = 1.01-1.13); (p = 0.02), and for each 1 unit increase in ln maximum SCC in the lactation before drying off the OR for SCM was 1.54 (95% CI = 1.13-2.10); (p = 0.01). There were 30/976 (3.1%) cows diagnosed with clinical mastitis in the first 60 days after calving. The odds of clinical mastitis were greater for cows producing >15 L/day at the last herd test of the preceding lactation than cows producing <10 L/day (OR = 4.79 (95% CI = 1.48-15.46); p = 0.009); for each 1 unit increase in ln maximum SCC in the previous lactation the OR for clinical mastitis was 1.96 (95% CI = 1.09-3.54); (p = 0.03), and the odds increased with increasing herd-level cow-case lactational incidence of clinical mastitis in the preceding lactation (p = 0.003). CONCLUSIONS AND CLINICAL RELEVANCE: Selection of cows with low SCC for ITS infusion should consider cow milk yield and maximum cow SCC in the preceding lactation.


Asunto(s)
Enfermedades de los Bovinos , Mastitis Bovina , Mastitis , Animales , Antibacterianos/uso terapéutico , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Recuento de Células/veterinaria , Industria Lechera , Femenino , Lactancia , Glándulas Mamarias Animales , Mastitis/veterinaria , Mastitis Bovina/tratamiento farmacológico , Mastitis Bovina/epidemiología , Mastitis Bovina/prevención & control , Leche , Factores de Riesgo
6.
J Dairy Sci ; 104(9): 10232-10249, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34053762

RESUMEN

To reduce antimicrobial use, infusion of antimicrobials into only infected cows at the end of lactation (selective dry cow therapy) is preferable to infusion of every cow with antimicrobials. Use of selective dry cow antimicrobial therapy requires differentiation of probably infected from uninfected cows to enable treatment allocation. Milk somatic cell count (SCC) has been used to distinguish between cows with and without intramammary infection (IMI). However, SCC may be influenced by milk yield, stage of lactation, breed, and herd-level variables such as prevalence of infection. Cut points for SCC, to distinguish between cows with and without an IMI, may need to differ between cow age groups and breeds, or among herds. This study evaluated associations between SCC and major pathogen IMI in one or more quarters of 2,606 cows from 36 herds in 4 regions of New Zealand. In the last week of lactation, cows selected at random had milk samples collected from each quarter, and the teat-end condition and hygiene of the udder were scored. Herd- and cow-level data including age, breed, milk volume, and SCC at each production were recorded, and bulk tank milk SCC and volume of milk shipped were collated. At cow level, the association between average, maximum, and last cow-composite SCC, and presence of a major pathogen IMI in one or more quarters of cows, was examined using receiver operator curves. Predictive logistic regression models were then developed that included potential effect modifiers such as age, milk yield, and bulk tank milk SCC. The population average prevalence of major pathogen IMI was 7.2% of cows (95% confidence interval = 5.9-8.6), and this varied significantly between herds. The average, maximum, and last cow-composite SCC of lactation were all predictive of presence of a major pathogen IMI and did not differ in their ability to discriminate infected from uninfected cows. However, the optimal cut points for the last SCC, the maximum SCC, and average SCC were 108, 152, and 105 × 1,000 cells/mL, respectively. Inclusion of age, bulk tank SCC, and history of clinical mastitis improved overall model fit. However, inclusion of these variables did not improve the discriminatory power of maximum cow-composite SCC used alone. We conclude that cow-composite SCC on its own resulted in sensitivities and specificities of between 0.76 and 0.86, and 0.71 to 0.80, respectively, for determination of presence of major pattern IMI, and the predictive value was not improved by addition of other predictor variables.


Asunto(s)
Enfermedades de los Bovinos , Mastitis Bovina , Animales , Bovinos , Recuento de Células/veterinaria , Femenino , Lactancia , Glándulas Mamarias Animales , Leche
7.
Br J Surg ; 107(12): 1562-1569, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32770742

RESUMEN

BACKGROUND: The management of lateral pelvic lymphadenopathy in low rectal cancer poses an oncological and technical challenge. Interpretation of the literature is confounded by different approaches to management in the East and West, and a lack of randomized data from which to draw accurate conclusions regarding the optimal approach. Recent collaboration between Eastern and Western centres has increased the standardization of care. Despite this, significant differences in international guidelines remain. The aim of this review was to appraise the available literature and propose a management algorithm. METHODS: A literature review of all relevant studies was performed to summarize the historical evidence, as well as establish the significance of clinically positive lateral pelvic sidewall nodes, and the role of neoadjuvant chemoradiotherapy and lateral pelvic node dissection. A management algorithm was developed based on this review of the literature. RESULTS: The management of pelvic sidewall lymphadenopathy in rectal cancer is non-standardized, with geographical differences. The mechanism of lateral lymphatic spread is well defined; the risk increases with lower tumour height and advanced T category. Existing data indicate that acceptable disease-free and overall survival can be achieved by neoadjuvant chemoradiotherapy with selective lateral pelvic node dissection. CONCLUSION: Suspicious lateral pelvic sidewall nodes, particularly in the internal iliac chain, should be considered as resectable locoregional disease, and surgery offered for enlarged nodes that do not respond to neoadjuvant chemoradiotherapy.


ANTECEDENTES: El tratamiento de las adenopatías en la pared pélvica lateral en el céncer de recto inferior plantea un desafío oncológico y técnico. La interpretación de la literatura es confusa por los diferentes abordajes en Oriente y Occidente y la falta de estudios aleatorizados a partir de los cuales extraer conclusiones precisas sobre cuél es el enfoque óptimo. La reciente colaboración entre los centros orientales y occidentales ha aumentado la estandarización del tratamiento. A pesar de ello, persisten diferencias significativas en las guías internacionales. El objetivo de esta revisión fue evaluar la literatura disponible y proponer un algoritmo terapéutico. MÉTODOS: Se realizó una revisión de la literatura de todos los estudios relevantes para resumir las evidencias existentes, así como para determinar la importancia de las adenopatías de la pared lateral pélvica clínicamente positivas, el papel de la quimiorradioterapia neoadyuvante (neoadjuvant chemoradiotherapy, NCRT) y de la linfadenectomía pélvica lateral (lateral pelvic node dissection, LPND). Se desarrolló un algoritmo de tratamiento basado en esta revisión de la literatura. RESULTADOS: El tratamiento de las adenopatías de la pared lateral de la pelvis en el céncer de recto no esté estandarizado y sigue habiendo diferencias geogréficas. El mecanismo de la diseminación linfética lateral esté bien definido con un mayor riesgo en los tumores de recto inferior y con un estadio T avanzado. Los datos existentes demuestran que se puede obtener una supervivencia libre de enfermedad y global aceptables mediante NCRT con LPND selectiva. CONCLUSIÓN: Las adenopatías sospechosas en la pared lateral de la pelvis, en particular en la cadena ilíaca interna, deben considerarse enfermedad locorregional resecable y se debe ofrecer cirugía para los ganglios aumentados de tamaño que no responden a la NCRT.


Asunto(s)
Ganglios Linfáticos/patología , Neoplasias del Recto/patología , Algoritmos , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/cirugía , Metástasis Linfática , Pelvis
8.
Support Care Cancer ; 28(9): 4395-4403, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31919665

RESUMEN

AIM: To assess the impact of a pilot nurse-led paediatric oncology fast-track clinic (OFTC) for complications and side effects following chemotherapy within a paediatric tertiary hospital. METHODS: Prospective clinical data from the first 100 patients seen in the OFTC were compared with retrospective data of oncology patient presentations to the emergency department (ED) (over a 1-year period, n = 196) who would have been eligible for review in the OFTC. Parent and patient satisfaction of clinical care were also assessed via surveys pre- and post-OFTC implementation. RESULTS: Analysis which achieved statistical difference was a reduction in the number of blood tubes taken in OFTC (average 1.9 for those discharged from clinic, 2.9 for those admitted from clinic) in comparison to those seen in the ED (average 3.2) (p = 0.0027). The average number of interventions per patient seen in the ED were 2.1 (standard deviation 1.64) compared with 1.7 (standard deviation 1.55) interventions per patient seen in the OFTC, and who were not admitted following review. This result approached statistical significance with p = 0.0963. Other results which did not meet statistical significance included a reduction in treatment times, hospital admissions and medical oncology reviews. CONCLUSION: Our pilot study implementing an OFTC for the triage and assessment of chemotherapy-related complications has proven successful from an operational and consumer perspective. The clinic improved care by ensuring expedited review, more streamlined interventions, and less overall hospital admissions. The improvements in efficiency were also mirrored by increased parent and patient satisfaction.


Asunto(s)
Instituciones de Atención Ambulatoria/normas , Hospitales Pediátricos/normas , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Oncología Médica , Enfermeras y Enfermeros , Estudios Prospectivos , Estudios Retrospectivos
9.
J Opt Soc Am A Opt Image Sci Vis ; 37(12): 1950-1957, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33362138

RESUMEN

Monitoring strain is important in precision engineering applications that require maintaining the precise alignments of structures over time, such as those found in machine tools and metrology frames. We present a fiber-optic strain measurement technique based upon broadband interferometry that is variously configurable in terms of gauge length and sensitivity. This is achieved by the use of an unbalanced interrogation interferometer configuration that alleviates the cavity length limit imposed by the temporal coherence of the system. We also demonstrate that dispersion in fiber sensors based on intrinsic Fabry-Perot interferometers must be considered to optimize performance. The possibility of multisensor interrogation using the same optical system is also reported.

10.
Appl Opt ; 58(1): 131-136, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30645519

RESUMEN

Interferometric instruments with dispersion introduced in the reference arm have previously been created, as the controlled dispersion can be used to generate a signal that contains a clearly identifiable point, the location of which relates to the position of the scattering surface in the measurement arm. In the following, we illustrate that the linear approximations that have been used previously can lead to significant errors, and that second-order terms need to be included in order to correct this. These corrections are vital if these instruments are to be used for metrological applications.

11.
Int Psychogeriatr ; 30(10): 1569, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29606176

RESUMEN

We read the paper by Soysal et al. (2017) with interest as we have experience of both the Attended With (AW) and the Head-Turning Sign (HTS) in a neurology-led cognitive disorders clinic.


Asunto(s)
Trastornos del Conocimiento/diagnóstico , Evaluación Geriátrica/métodos , Movimientos de la Cabeza , Anciano , Femenino , Humanos , Masculino
12.
Matern Child Health J ; 21(5): 966-973, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28083732

RESUMEN

Introduction To determine the association of fruit and vegetable consumption with overall sleep duration among pregnant women. Methods Data from the 2011 and 2012 Behavioral Risk Factors Surveillance System (BRFSS) were used. All women (n = 2951) of childbearing age (18-44 years) who were pregnant and responded to all fruit and vegetable consumption and sleep duration questions were included. Covariates included age, race, education level, exercise, and marital status. Data were analyzed using linear and ordinal logistic regression. Results Total daily fruit and vegetable consumption was not associated with sleep duration among pregnant women, controlling for confounders [ß = -0.03, (-0.07, 0.00)]. Orange and green vegetable consumption were both inversely associated with sleep duration [ß = -0.19, (-0.38, -0.01) and ß = -0.20, (-0.33, -0.08) respectively]. Ordinal logistic regression found that the odds of meeting or exceeding sleep time recommendations increased slightly with each unit increase in total fruit and vegetable consumption [OR = 1.05 (1.003, 1.092)] and for every unit increase in fruit consumption [OR = 1.12 (1.038, 1.208)]. Women who exercised within the past 30 days reported approximately 20 min of additional sleep compared to those who did not [ß = 0.32 (0.16, 0.49)]. Age, employment status, and marital status were also independently associated with sleep duration. Discussion Sleep duration in pregnant women was associated with exercise and other demographic factors, but only mildly associated with fruit and vegetable consumption. Future research should investigate the effects of additional factors including sleep quality, gestational age, family status and other medications as potential confounders.


Asunto(s)
Dieta Saludable/normas , Frutas , Sueño/fisiología , Factores de Tiempo , Verduras , Adolescente , Adulto , Femenino , Humanos , Embarazo
13.
J Dairy Sci ; 100(5): 3816-3824, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28237588

RESUMEN

The performance of a commercial, real-time PCR assay was compared with traditional bacterial culture for the identification of Streptococcus uberis and Staphylococcus aureus in bovine milk collected at different stages of lactation. Initial validation tests using fresh and frozen quarter milk samples identified factors that affected the success of the PCR. Therefore, the standard protocol was adjusted for samples collected at the first milking postpartum (colostrum) and from clinical mastitis cases. The adjustment involved PCR testing both undiluted and diluted (1 in 10 with sterile water) DNA extracts. The performance comparison between culture and the PCR assay used milk samples collected aseptically from individual quarters of mixed-age spring-calving dairy cows, during early, mid, and late lactation. Bacterial culture results were used to select a subset of samples for PCR testing (n = 315) that represented quarters with a current or prior Strep. uberis or Staph. aureus infection. Compared with culture, PCR had a sensitivity of 86.8% and specificity of 87.7% for detecting Strep. uberis (kappa = 0.74) and 96.4% and 99.7%, respectively, for detecting Staph. aureus (kappa = 0.96). The dilution of DNA extracts for colostrum and clinical samples increased the relative sensitivity from 79.2% to 86.8% for Strep. uberis detection and from 92.9% to 96.4% for Staph. aureus, presumably through diluting unidentified PCR inhibitors. The sensitivity for detecting Strep. uberis using PCR, relative to culture, was similar throughout lactation (85-89%), whereas relative specificity was lowest immediately postcalving (64%) but improved in mid and late lactation (98%). Specificity estimates for samples collected in early lactation can be optimized by reducing the cutoff cycle threshold (Ct) value from the recommended value of 37 to 34. Although using this value improved specificity (77%), it reduced test sensitivity (77%). The PCR assay lacked agreement with culture in early lactation, specifically for diagnosing Strep. uberis. Thus, PCR should not be used as the only tool for diagnosing mastitis in early lactation.


Asunto(s)
Mastitis Bovina/microbiología , Staphylococcus aureus/genética , Animales , Bovinos , Femenino , Lactancia , Leche/microbiología , Infecciones Estafilocócicas/veterinaria , Infecciones Estreptocócicas/veterinaria , Streptococcus
14.
J Fish Biol ; 91(6): 1582-1602, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29034467

RESUMEN

Potential roles of the rostrum of sawsharks (Pristiophoridae), including predation and self-defence, were assessed through a variety of inferential methods. Comparison of microwear on the surface of the rostral teeth of sawsharks and sawfishes (Pristidae) show that microwear patterns are alike and suggest that the elongate rostra in these two elasmobranch families are used for a similar purpose (predation). Raman spectroscopy indicates that the rostral teeth of both sawsharks and sawfishes are composed of hydroxyapatite, but differ in their collagen content. Sawfishes possess collagen throughout their rostral teeth whereas collagen is present only in the centre of the rostral teeth of sawsharks, which may relate to differences in ecological use. The ratio of rostrum length to total length in the common sawshark Pristiophorus cirratus was found to be similar to the largetooth sawfish Pristis pristis but not the knifetooth sawfish Anoxypristis cuspidata. Analysis of the stomach contents of P. cirratus indicates that the diet consists of demersal fishes and crustaceans, with shrimp from the family Pandalidae being the most important dietary component. No prey item showed evidence of wounds inflicted by the rostral teeth. In light of the similarities in microwear patterns, rostral tooth chemistry and diet with sawfishes, it is hypothesised that sawsharks use their rostrum in a similar manner for predation (sensing and capturing prey) and possibly for self-defence.


Asunto(s)
Elasmobranquios/fisiología , Diente/anatomía & histología , Animales , Dieta , Elasmobranquios/anatomía & histología , Conducta Predatoria , Rajidae , Espectrometría Raman , Diente/química , Diente/fisiología
15.
J Fish Biol ; 90(5): 1906-1925, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28303565

RESUMEN

The internal anatomy of the barbels of the common sawshark Pristiophorus cirratus was examined with light microscopy to clarify their sensory role. No sensory structures such as taste buds (chemoreception), ampullae of Lorenzini (electroreception) or free neuromasts (lateral line mechanoreception) could be located in the barbels. The presence of bundles of nerve fibres, however, indicates a tactile function for the barbels. Conveyance of information regarding potentially damaging stimuli (nociception) and temperature (thermoception) cannot be excluded at this stage. It is hypothesized that the barbels are used by P. cirratus to locate prey in both the water column and on the substratum via wake detection and sensing changes in surface texture. The barbels may also be involved in the detection of water currents for rheotaxis. Regression analyses on P. cirratus morphometric data showed that the width of the rostrum at two sections (the barbels and the rostrum tip) does not significantly correlate with total length. The regression analyses also suggested that the barbels of P. cirratus may be lateralised.


Asunto(s)
Estructuras Animales/ultraestructura , Elasmobranquios/anatomía & histología , Animales , Elasmobranquios/fisiología , Fibras Nerviosas/ultraestructura , Análisis de Regresión , Células Receptoras Sensoriales/fisiología , Células Receptoras Sensoriales/ultraestructura , Percepción del Tacto/fisiología
16.
Am J Gastroenterol ; 111(6): 800-7, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27021194

RESUMEN

OBJECTIVES: Measures for evaluating interventional endoscopy unit efficiency have not been adequately validated, especially in reference to the involvement of anesthesia services for endoscopy. Primary aim was to compare process measures/metrics of interventional endoscopy unit efficiency between intubated and non-intubated patients. Secondary aim was to assess variables associated with the need for endotracheal intubation. METHODS: The prospectively collected endoscopy unit metrics database at UF Health was reviewed for procedures performed in the interventional endoscopy unit for 6 months. Parameters included hospital-mandated metrics available from the database. RESULTS: A total of 1,421 patients underwent 1,635 interventional endoscopic procedures and 271/1,421 patients (19.1%) were intubated. There was no significant difference between intubated and non-intubated cohorts with respect to age, gender, BMI, ASA Score, Mallampati Score, or the Charlson Comorbidity Index. Patients undergoing endoscopic retrograde cholangiopancreatography (ERCP) were more frequently intubated than those undergoing non-ERCP procedures (41.3 vs. 12.4%, P<0.0001). Inpatients comprised 48.3% of all intubated patients, whereas only 29.2% of non-intubated patients were inpatients (P<0.0001). Most patients (159/271, 58.7%) were intubated per anesthesiologist preference. All process efficiency metrics were significantly prolonged in the intubated compared with the non-intubated patient cohort, except the time interval between successive procedures. Multivariate analysis revealed that patients with an anesthesiologist who had performed a greater number of total endoscopic sedations were less likely to be intubated than patients with an anesthesiologist who had performed fewer total procedures (P=0.0066). CONCLUSIONS: Endotracheal intubation negatively impacts efficiency metrics in an interventional endoscopy unit. Careful assessment for the need for intubation should be emphasized.


Asunto(s)
Endoscopía Gastrointestinal , Intubación Intratraqueal/estadística & datos numéricos , Centros Médicos Académicos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Colangiopancreatografia Retrógrada Endoscópica , Comorbilidad , Femenino , Florida , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sigmoidoscopía , Resultado del Tratamiento
17.
Genome ; 59(9): 771-81, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27595914

RESUMEN

Species in the cycad genus Encephalartos are listed in CITES Appendix I and as Threatened or Protected Species in terms of South Africa's National Environmental Management: Biodiversity Act (NEM:BA) of 2004. Despite regulations, illegal plant harvesting for medicinal trade has continued in South Africa and resulted in declines in cycad populations and even complete loss of sub-populations. Encephalartos is traded at traditional medicine markets in South Africa in the form of bark strips and stem sections; thus, determining the species traded presents a major challenge due to a lack of characteristic plant parts. Here, a case study is presented on the use of DNA barcoding to identify cycads sold at the Faraday and Warwick traditional medicine markets in Johannesburg and Durban, respectively. Market samples were sequenced for the core DNA barcodes (rbcLa and matK) as well as two additional regions: nrITS and trnH-psbA. The barcoding database for cycads at the University of Johannesburg was utilized to assign query samples to known species. Three approaches were followed: tree-based, similarity-based, and character-based (BRONX) methods. Market samples identified were Encephalartos ferox (Near Threatened), Encephalartos lebomboensis (Endangered), Encephalartos natalensis (Near Threatened), Encephalartos senticosus (Vulnerable), and Encephalartos villosus (Least Concern). Results from this study are crucial for making appropriate assessments and decisions on how to manage these markets.


Asunto(s)
Cycadopsida/clasificación , Cycadopsida/genética , Código de Barras del ADN Taxonómico , Medicina Tradicional , Biodiversidad , ADN Intergénico , ADN de Plantas , Filogenia , Sudáfrica
19.
J Clin Pharm Ther ; 41(4): 441-443, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27207573

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Voriconazole has significant drug interactions due to metabolism by CYP enzymes. Subtherapeutic voriconazole concentrations associated with concomitant dexamethasone are not well described. CASE DESCRIPTION: An 84-year-old male was started on voriconazole for a fungal brain abscess. He was readmitted due to clinical failure thought to be the result of subtherapeutic voriconazole concentrations. Dexamethasone was identified as a potential cause due to its induction of CYP enzymes. This interaction was substantiated by sequential troughs that demonstrated a rise in voriconazole concentrations as dexamethasone was tapered off. WHAT IS NEW AND CONCLUSION: Therapeutic drug monitoring for patients on voriconazole and dexamethasone is essential to prevent suboptimal clinical outcomes.

20.
Osteoarthritis Cartilage ; 23(7): 1090-8, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25887362

RESUMEN

PURPOSE: Report the radiographic and magnetic resonance imaging (MRI) structural outcomes of an 18-month study of diet-induced weight loss, with or without exercise, compared to exercise alone in older, overweight and obese adults with symptomatic knee osteoarthritis (OA). METHODS: Prospective, single-blind, randomized controlled trial that enrolled 454 overweight and obese (body mass index, BMI = 27-41 kg m(-2)) older (age ≥ 55 yrs) adults with knee pain and radiographic evidence of femorotibial OA. Participants were randomized to one of three 18-month interventions: diet-induced weight loss only (D); diet-induced weight loss plus exercise (D + E); or exercise-only control (E). X-rays (N = 325) and MRIs (N = 105) were acquired at baseline and 18 months follow-up. X-ray and MRI (cartilage thickness and semi-quantitative (SQ)) results were analyzed to compare change between groups at 18-month follow-up using analysis of covariance (ANCOVA) adjusted for baseline values, baseline BMI, and gender. RESULTS: Mean baseline descriptive characteristics of the cohort included: age, 65.6 yrs; BMI 33.6 kg m(-2); 72% female; 81% white. There was no significant difference between groups in joint space width (JSW) loss; D -0.07 (SE 0.22) mm, D + E -0.27 (SE 0.22) mm and E -0.16 (SE 0.24) mm (P = 0.79). There was also no significant difference in MRI cartilage loss between groups; D -0.10(0.05) mm, D + E -0.13(0.04) mm and E -0.05(0.04) mm (P = 0.42). CONCLUSION: Despite the potent effects of weight loss in this study on symptoms as well as mechanistic outcomes (such as joint compressive force and markers of inflammation), there was no statistically significant difference between the three active interventions on the rate of structural progression either on X-ray or MRI over 18-months.


Asunto(s)
Dieta Reductora , Terapia por Ejercicio/métodos , Osteoartritis de la Rodilla/terapia , Anciano , Índice de Masa Corporal , Terapia Combinada , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/dietoterapia , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/etiología , Radiografía , Índice de Severidad de la Enfermedad , Método Simple Ciego , Resultado del Tratamiento , Pérdida de Peso
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