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1.
Int J Life Cycle Assess ; 28(2): 146-155, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36685326

RESUMEN

Goal and theoretical commentary: A number of recent life cycle assessment (LCA) studies have concluded that animal-sourced foods should be restricted-or even avoided-within the human diet due to their relatively high environmental impacts (particularly those from ruminants) compared with other protein-rich foods (mainly protein-rich plant foods). From a nutritional point of view, however, issues such as broad nutrient bioavailability, amino acid balances, digestibility and even non-protein nutrient density (e.g., micronutrients) need to be accounted for before making such recommendations to the global population. This is especially important given the contribution of animal sourced foods to nutrient adequacy in the global South and vulnerable populations of high-income countries (e.g., children, women of reproductive age and elderly). Often, however, LCAs simplify this reality by using 'protein' as a functional unit in their models and basing their analyses on generic nutritional requirements. Even if a 'nutritional functional unit' (nFU) is utilised, it is unlikely to consider the complexities of amino acid composition and subsequent protein accretion. The discussion herein focuses on nutritional LCA (nLCA), particularly on the usefulness of nFUs such as 'protein,' and whether protein quality should be considered when adopting the nutrient as an (n)FU. Further, a novel and informative case study is provided to demonstrate the strengths and weaknesses of protein-quality adjustment. Case study methods: To complement current discussions, we present an exploratory virtual experiment to determine how Digestible Indispensable Amino Acid Scores (DIAAS) might play a role in nLCA development by correcting for amino acid quality and digestibility. DIAAS is a scoring mechanism which considers the limiting indispensable amino acids (IAAs) within an IAA balance of a given food (or meal) and provides a percentage contribution relative to recommended daily intakes for IAA and subsequent protein anabolism; for clarity, we focus only on single food items (4 × animal-based products and 4 × plant-based products) in the current case exemplar. Further, we take beef as a sensitivity analysis example (which we particularly recommend when considering IAA complementarity at the meal-level) to elucidate how various cuts of the same intermediary product could affect the interpretation of nLCA results of the end-product(s). Recommendations: First, we provide a list of suggestions which are intended to (a) assist with deciding whether protein-quality correction is necessary for a specific research question and (b) acknowledge additional uncertainties by providing mitigating opportunities to avoid misinterpretation (or worse, dis-interpretation) of protein-focused nLCA studies. We conclude that as relevant (primary) data availability from supply chain 'gatekeepers' (e.g., international agri-food distributors and processors) becomes more prevalent, detailed consideration of IAA provision of contrasting protein sources needs to be acknowledged-ideally quantitatively with DIAAS being one example-in nLCA studies utilising protein as a nFU. We also contend that future nLCA studies should discuss the complementarity of amino acid balances at the meal-level, as a minimum, rather than the product level when assessing protein metabolic responses of consumers. Additionally, a broader set of nutrients should ideally be included when evaluating "protein-rich foods" which provide nutrients that extend beyond amino acids, which is of particular importance when exploring dietary-level nLCA.

2.
J Water Health ; 20(9): 1314-1328, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36170188

RESUMEN

Between 2014 and 2016, there were two severe community water system (CWS) failures in Flint, Michigan (MI), USA and Havelock North, Hawkes Bay, New Zealand. These events had profound implications for public health in their respective countries. While the nature of both crises was different, certain aspects of the failings were strikingly similar. These included: failure of authorities to protect the integrity of their source water, 'wait-and-see approach' to address problems if and when they occurred, negligent approach to regulatory oversight and responsibility, substandard facilities and lack of knowledge and training of staff, failure of consultants and advisory services engaged by suppliers, and failure of government agencies to enforce regulations. The lessons from both incidents must be learned, or similar tragic events are likely to reoccur. The six principles identified in the Government Inquiry into the Havelock North outbreak are an essential first step. The next step is to implement them throughout the drinking water sector.


Asunto(s)
Agua Potable , Brotes de Enfermedades , Humanos , Michigan/epidemiología , Salud Pública , Gestión de Riesgos , Abastecimiento de Agua
3.
J Biomech ; 135: 111015, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35259658

RESUMEN

Horizontal jumps are discrete, fast, over-ground movements requiring coordination of the centre of mass (CoM) and base of support and are routinely assessed in sports settings. There is currently no biomechanics-based system to aid in their quick and objective large-scale assessment. We describe a practical system combining a single low-cost depth-sensing camera and point-cloud processing (PCP) to capture whole-body CoM and foot kinematics. Fourteen participants performed 10 single-leg horizontal jumps for distance. Foot displacement, CoM displacement, CoM peak velocity and CoM peak acceleration in the anterior-posterior direction of movement were compared with a reference 15-segment criterion model, captured concurrently using a nine-camera motion capture system (Vicon Motion Systems, UK). Between-system Pearson's correlations were very-large to near-perfect (n = 140; foot displacement = 0.99, CoM displacement = 0.98, CoM peak velocity = 0.97, CoM peak acceleration = 0.79), with mean biases being trivial-small (-0.07 cm [0.12%], 3.8 cm [3.5%], 0.03 m·s-1 [1.6%], 0.42 m·s-2 [7%], respectively) and typical errors being trivial-small for displacement (foot: 0.92 cm [0.8%]; CoM: 3.8 cm [3.4%]) and CoM peak velocity (0.07 m·s-1 [4.3%]), and large for CoM peak acceleration (0.72 m·s-2 [15%]). Limits of agreement were -1.9 to 2.0 cm for foot displacement, -11.3 to 3.6 cm for CoM displacement, -0.17 to 0.12 m·s-1 for CoM peak velocity and -2.28 to 1.43 m·s-2 for CoM peak acceleration. The practical system captured CoM and foot kinematics during horizontal jumps with acceptable precision. Further work to improve estimates of CoM accelerations and different populations are warranted.


Asunto(s)
Nube Computacional , Pie , Aceleración , Fenómenos Biomecánicos , Humanos , Extremidad Inferior
4.
Eur J Sport Sci ; 20(4): 505-515, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31322477

RESUMEN

Intermittent exercise might be an efficient means of exercise for improving bone strength and quality. The aim of our study was to examine the effect of intermittent running on bone turnover markers using altered exercise-to-rest intervals. Twelve males completed one control (no exercise), and three, 45-min intermittent protocols (5, 20, and 80 s intervals) matched for distance and speed. Fasted venous blood samples were collected at baseline, 1, 2 and 24 h post-exercise. Carboxyterminal crosslinked telopeptide (CTX-I) and procollagen type 1 amino-terminal propeptide (P1NP) were used as markers of bone resorption and formation. After adjustment for baseline, CTX-I concentration at 1 h was higher (very likely to most likely small) for 5 s (30.2%; ±90% confidence limits: 10%), 20 s (2.9.0%; ±10%) and 80 s (32.0%; ±10%) compared to control. The very likely small effect remained for 5 s at 2 h (30.2%; ±15%). The effect for 20 and 80 s was possibly trivial and possibly small/possibly trivial (∼14.5%; ±âˆ¼15%). Differences in P1NP concentrations were likely to very likely trivial (∼7.4%; ±âˆ¼7.6%). Circulating CTX-I concentration is affected acutely by intermittent running with short-interval (5 s) intermittent loading resulting in a prolonged attenuation in circadian rhythm of CTX-I up to 2 h that was not demonstrated as clearly by longer intervals despite matched internal and external training load.


Asunto(s)
Biomarcadores/metabolismo , Remodelación Ósea , Colágeno Tipo I/metabolismo , Fragmentos de Péptidos/metabolismo , Péptidos/metabolismo , Procolágeno/metabolismo , Carrera , Adolescente , Adulto , Voluntarios Sanos , Humanos , Masculino , Adulto Joven
5.
Chem Biol Interact ; 49(1-2): 165-76, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6539175

RESUMEN

After the administration of the anticancer drug cis-dichlorodiammine platinum II (cisplatin) to male rats, the Pt in the soluble fraction of the kidney is isolated, by gel filtration, in association with a high molecular weight component and a low molecular weight fraction. At 24 h, Pt is also recovered in a metallothionein-like fraction which elutes from Sephadex G-50 with a lower apparent molecular weight than endogenous (Cu, Zn)-thionein or Cd-thionein isolated from the kidneys of Cd2+-treated rats. None of these low molecular weight metal-binding fractions binds to Octyl Sepharose CL-4B. On DE-52 ion exchange chromatography, Cd-thionein is resolved into two isometallothioneins whereas the low molecular weight Pt-binding fraction is only partially purified and contains at least six components which elute at higher gradient concentrations than metallothionein. Pretreatment with Cd2+ which stimulates the synthesis of renal and hepatic metallothionein has no effect on the uptake and subcellular distribution of Pt in the liver and kidneys. Cisplatin treatment reduces the concentration of Cu and Zn in the renal metallothionein and other soluble protein fractions in the kidney. When administered to Cd2+-pretreated rats, cisplatin promotes the loss of Zn from the soluble protein fractions but causes the redistribution of Cd from the metallothionein to the high molecular weight fraction and fails to inhibit the Cd2+-induced accumulation of Cu in the kidneys and the binding of Cu to the soluble protein fractions. It is suggested that metallothionein probably does not have a significant role in the renal metabolism of Pt following the administration of cisplatin to rats.


Asunto(s)
Cisplatino/farmacología , Riñón/metabolismo , Metalotioneína/metabolismo , Platino (Metal)/metabolismo , Animales , Cadmio/metabolismo , Cadmio/farmacología , Cisplatino/metabolismo , Cobre/metabolismo , Riñón/efectos de los fármacos , Masculino , Peso Molecular , Ratas , Ratas Endogámicas , Zinc/metabolismo
6.
Environ Pollut ; 90(1): 67-73, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-15091502

RESUMEN

A year-long survey, with samples collected weekly, was conducted to estimate long-term average concentrations of arsenic in treated and untreated drinking water for the city of Hamilton, New Zealand. The average concentration of arsenic in Waikato River water at Hamilton before processing was found to be (32.1 +/- 3.7) microg litre(-1), about three times above the new WHO limit of 10 microg litre(-1). However, full conventional water treatment effects a five-fold reduction in arsenic concentrations in drinking water to a level which meets the new standards of (6.2 +/- 0.8) microg litre(-1). The results of both this study and retrospective analysis of archived data suggest that total arsenic concentrations in the Waikato River are likely to follow a regular seasonal variation, being about 10-25 microg litre(-1) higher in the summer months. Changes in river flow rates have an almost negligible effect on the summer peak and winter trough; it is proposed that most of the variation in total arsenic concentrations may be due to the seasonal conversion of arsenic in the river sediments to more soluble forms.

7.
Sci Total Environ ; 319(1-3): 99-113, 2004 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-14967504

RESUMEN

Concentrations of 222Rn were measured in ancient copper mines which exploited the Faynan Orefield in the South-Western Jordanian Desert. The concentrations of radon gas detected indicate that the ancient metal workers would have been exposed to a significant health risk and indicate that any future attempt to exploit the copper ores must deal with the hazard identified. Seasonal variations in radon concentrations are noted and these are linked to the ventilation of the mines. These modern data are used to explore the differential exposure to radon and the health of ancient mining communities.


Asunto(s)
Exposición a Riesgos Ambientales , Monitoreo del Ambiente , Radón/química , Fenómenos Geológicos , Geología , Jordania , Minería , Medición de Riesgo , Estaciones del Año
8.
Biomed Mass Spectrom ; 3(6): 281-5, 1976 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1000058

RESUMEN

A sensitive method for the simulataneous determination of bufuralol and its pharmacologically active metabolites in huamn plasma is described. The O-timethylsilyl,N-trifluoroacetyl derivatives are assayed by mass fragmentography. Sensitivity is 1 ng 76(-1) plasma for bufaralol and about 250 pg ml(-1) for the metabolites. An alternative procedure which uses gas chromatography with electron capture detection is also described. The sensitivity of this is about 10 ng ml(-1) plasma for all drug-related components.


Asunto(s)
Cromatografía de Gases/métodos , Etanolaminas/sangre , Cromatografía de Gases y Espectrometría de Masas , Benzofuranos/sangre , Benzofuranos/farmacología , Electrones , Etanolaminas/farmacología , Humanos , Técnicas In Vitro , Cetonas/sangre , Espectrometría de Masas , Fenoles/sangre
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