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1.
Artículo en Inglés | MEDLINE | ID: mdl-38682238

RESUMEN

We recently demonstrated that acute oral ketone monoester intake induces a stimulation of postprandial myofibrillar protein synthesis rates comparable to that elicited following the ingestion of 10 g whey protein or their co-ingestion. The present investigation aimed to determine the acute effects of ingesting a ketone monoester, whey protein, or their co-ingestion on mTOR-related protein-protein co-localization and intracellular trafficking in human skeletal muscle. In a randomized, double-blind, parallel group design, 36 healthy recreationally active young males (age: 24.2±4.1 y) ingested either: 1) 0.36 g ∙ kg-1 bodyweight of the ketone monoester (R)-3-hydroxybutyl (R)-3-hydroxybutyrate (KET), 2) 10 g whey protein (PRO), or 3) the combination of both (KET+PRO). Muscle biopsies were obtained in the overnight postabsorptive state (basal conditions), and at 120- and 300-minutes in the postprandial period for immunofluorescence assessment of protein translocation and co-localization of mTOR-related signaling molecules. All treatments resulted in a significant (Interaction: P<0.0001) decrease in tuberous sclerosis complex 2 (TSC2)-Ras homolog enriched in brain (Rheb) co-localization at 120-minutes vs. basal; however, the decrease was sustained at 300-minutes vs. basal (P<0.0001) only in KET+PRO. PRO and KET+PRO increased (Interaction: P<0.0001) mTOR-Rheb co-localization at 120-minutes vs. basal; however, KET+PRO resulted in a sustained increase in mTOR-Rheb co-localization at 300-minutes that was greater than KET and PRO. Treatment intake increased mTOR-wheat germ agglutinin (WGA) co-localization at 120- and 300-minutes (Time: P=0.0031), suggesting translocation toward the fiber periphery. These findings demonstrate that ketone monoester intake can influence the spatial mechanisms involved in the regulation of mTORC1 in human skeletal muscle.

2.
Am J Clin Nutr ; 119(3): 716-729, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38215886

RESUMEN

BACKGROUND: Ketone bodies may have anabolic effects in skeletal muscle via their capacity to stimulate protein synthesis. Whether orally ingested exogenous ketones can stimulate postprandial myofibrillar protein synthesis (MyoPS) rates with and without dietary protein co-ingestion is unknown. OBJECTIVES: This study aimed to evaluate the effects of ketone monoester intake and elevated blood ß-hydroxybutyrate (ß-OHB) concentration, with and without dietary protein co-ingestion, on postprandial MyoPS rates and mechanistic target of rapamycin complex 1 (mTORC1) pathway signaling. METHODS: In a randomized, double-blind, parallel group design, 36 recreationally active healthy young males (age: 24.2 ± 4.1 y; body fat: 20.9% ± 5.8%; body mass index: 23.4 ± 2 kg/m2) received a primed continuous infusion of L-[ring-2H5]-phenylalanine and ingested one of the following: 1) the ketone monoester (R)-3-hydroxybutyl (R)-3-hydroxybutyrate (KET), 2) 10 g whey protein (PRO), or 3) the combination of both (KET+PRO). Blood and muscle biopsy samples were collected during basal and postprandial (300 min) conditions to assess ß-OHB, glucose, insulin, and amino acid concentrations, MyoPS rates, and mTORC1 pathway signaling. RESULTS: Capillary blood ß-OHB concentration increased similarly during postprandial conditions in KET and KET+PRO, with both being greater than PRO from 30 to 180 min (treatment × time interaction: P < 0.001). Postprandial plasma leucine and essential amino acid (EAA) incremental area under the curve (iAUC) over 300 min was greater (treatment: both P < 0.001) in KET+PRO compared with PRO and KET. KET, PRO, and KET+PRO stimulated postprandial MyoPS rates (0-300 min) higher than basal conditions [absolute change: 0.020%/h; (95% CI: 0.013, 0.027%/h), 0.014%/h (95% CI: 0.009, 0.019%/h), 0.019%/h (95% CI: 0.014, 0.024%/h), respectively (time: P < 0.001)], with no difference between treatments (treatment: P = 0.383) or treatment × time interaction (interaction: P = 0.245). mTORC1 pathway signaling responses did not differ between treatments (all P > 0.05). CONCLUSIONS: Acute oral intake of a ketone monoester, 10 g whey protein, or their co-ingestion in the overnight postabsorptive state elicit a similar stimulation of postprandial MyoPS rates in healthy young males. This trial was registered at clinicaltrials.gov as NCT04565444 (https://clinicaltrials.gov/study/NCT04565444).


Asunto(s)
Proteínas en la Dieta , Cetonas , Adulto , Humanos , Masculino , Adulto Joven , Ingestión de Alimentos , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Músculo Esquelético/metabolismo , Periodo Posprandial , Proteína de Suero de Leche , Método Doble Ciego
3.
Nutr Res Rev ; : 1-14, 2023 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-37681443

RESUMEN

Branched-chain amino acids (BCAA: leucine, isoleucine and valine) are three of the nine indispensable amino acids, and are frequently consumed as a dietary supplement by athletes and recreationally active individuals alike. The popularity of BCAA supplements is largely predicated on the notion that they can stimulate rates of muscle protein synthesis (MPS) and suppress rates of muscle protein breakdown (MPB), the combination of which promotes a net anabolic response in skeletal muscle. To date, several studies have shown that BCAA (particularly leucine) increase the phosphorylation status of key proteins within the mechanistic target of rapamycin (mTOR) signalling pathway involved in the regulation of translation initiation in human muscle. Early research in humans demonstrated that BCAA provision reduced indices of whole-body protein breakdown and MPB; however, there was no stimulatory effect of BCAA on MPS. In contrast, recent work has demonstrated that BCAA intake can stimulate postprandial MPS rates at rest and can further increase MPS rates during recovery after a bout of resistance exercise. The purpose of this evidence-based narrative review is to critically appraise the available research pertaining to studies examining the effects of BCAA on MPS, MPB and associated molecular signalling responses in humans. Overall, BCAA can activate molecular pathways that regulate translation initiation, reduce indices of whole-body and MPB, and transiently stimulate MPS rates. However, the stimulatory effect of BCAA on MPS rates is less than the response observed following ingestion of a complete protein source providing the full complement of indispensable amino acids.

7.
Prog Urol ; 31(16): 1080-1089, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34538741

RESUMEN

BACKGROUND: Focal therapy is recently gaining popularity as an intermediate option between active surveillance and whole-gland treatment for localized prostate cancer. OBJECTIVE: This comprehensive review aims to present the different focal therapy technologies available to date while tackling the rationale for focal treatment, its indications, principles and outcomes of each technique. EVIDENCE ACQUISITION: A comprehensive review of the PubMed, Embase, and Web of Science was done. Keywords used for research were: "prostate cancer"; "focal therapy"; "focal treatment"; "High-Intensity Focal Ultrasound"; "cryotherapy"; "photodynamic therapy"; "focal laser ablation"; "irreversible electroporation"; "focal brachytherapy" and "gold nanoparticle directed therapy". Accepted languages were English and French. EVIDENCE SYNTHESIS: Choosing the best candidate for focal therapy is crucial (localized small to medium sized Gleason≤7 lesions). Focal high-intensity focal ultrasound has shown excellent survival rates at 5 years, while maintaining good functional outcomes (urinary continence and erectile function). Focal cryotherapy, one of the oldest focal treatments for prostate cancer, has shown good oncologic outcomes, with good continence rates and fair erectile function rates. Focal laser ablation seems a safe and feasible technique, with promising results. Irreversible electroporation has demonstrated good survival outcomes with no biochemical recurrence or disease relapse in the preliminary studies. Focal brachytherapy has a good toxicity profile, a good biochemical outcome, and gives a sustained quality of life. Finally, gold nanoparticle directed therapy is safe and is being studied in current trials. CONCLUSION: While proven to be safe in terms of continence and sexual aspects, the challenge remains to better assess oncological outcomes of these techniques in randomized longer follow-up studies.


Asunto(s)
Nanopartículas del Metal , Neoplasias de la Próstata , Crimen , Oro , Humanos , Masculino , Neoplasias de la Próstata/terapia , Castigo , Calidad de Vida
9.
Transl Oncol ; 14(6): 101071, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33744727

RESUMEN

Immune checkpoint inhibitors such as programmed death protein 1/programmed death-ligand 1 and cytotoxic T-lymphocyte-associated protein 4 inhibitors are already playing a central role in the treatment of metastatic renal cell carcinoma. However, they seem to be only effective in a subset of patients, with a high risk of innate and adaptive tumor resistance. Consequently, biomarkers capable of predicting immune treatment efficacy in advanced renal cancer are needed both in the clinical and the experimental setting. We hereby present a brief summary of evidence on the most studied biomarkers in metastatic renal cell carcinoma with a focus on the possible future place of T cell immunoglobulin and mucin domain-3 (TIM-3).

10.
Analyst ; 146(6): 1973-1980, 2021 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-33502395

RESUMEN

This work describes a new method for the analysis of handwritten documents through a system composed of a pre-selector optical analyser equipped with light sources of different wavelengths coupled with bandpass filters combined with an optical coherence tomography (OCT) instrument. The optical analyser identifies regions with different pen pressures on the paper using specific wavelengths from ultraviolet (UV) to infrared (IR) and bandpass filters. Then the selected regions are analysed with a coherence tomography analyser to measure the depth of grooves and capture three-dimensional images. With this methodology, it is possible to identify similarities, or differences, between the pieces of evidence under investigation, increasing the possibility of correct attribution concerning the authorship of the signature and we also showed that this feature is independent of the paper substrate. In this work, a new strategy will be presented to categorize and quantify pen pressure in order to aid a better response for a forensic examiner. Thereby, from the observed areas that display higher pressures (more significant grooves), it is possible to determine the authorship of the signature.

11.
J Oncol Pharm Pract ; 27(2): 514-515, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33349147

RESUMEN

Immunotherapy is gradually revolutionizing bladder cancer treatment. In this extensive review published by Hanna et al. in your journal, the authors presented recent studies that are trying to challenge the standard platinum-based chemotherapy as first-line treatment of metastatic bladder cancer by chemoimmunotherapy. However, upfront pembrolizumab, atezolizumab and durvalumab association with standard of care chemotherapy did not improve overall survival when compared to chemotherapy alone.We hereby highlight a study that was not included in this review, the INDUCOMAIN trial, by discussing its results and its future implications on immunotherapy for metastatic bladder cancer.


Asunto(s)
Carcinoma de Células Transicionales/terapia , Inmunoterapia/tendencias , Neoplasias de la Vejiga Urinaria/terapia , Antineoplásicos/uso terapéutico , Carcinoma de Células Transicionales/tratamiento farmacológico , Ensayos Clínicos como Asunto , Humanos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico
12.
Front Sports Act Living ; 2: 568740, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33345126

RESUMEN

Background: Variable intensity training (VIT) characteristic of stop-and-go team sport exercise may reduce performance capacity when performed on successive days but also represent a strategy to induce rapid training-induced increases in exercise capacity. Although post-exercise protein enhances muscle protein synthesis, the timing of protein ingestion following variable intensity training (VIT) on next-day recovery and short-term performance adaptation is unknown. Purpose: To determine if immediate (IMM) as compared to delayed (DEL) protein ingestion supports greater acute recovery of exercise performance during successive days of VIT and/or supports chronic training adaptations. Methods: Sixteen habitually active men performed 5 consecutive days of variable intensity training (VIT) in the evening prior to consuming a beverage providing carbohydrate and whey protein (IMM; 0.7 g and 0.3 g/kg, respectively) or carbohydrates alone (DEL; 1 g/kg) with the reciprocal beverage consumed the following morning. Performance was assessed before each VIT (recovery) and 2 days after the final VIT (adaptation). Results: Five consecutive days of VIT progressively decreased anaerobic peak power (~7%) and muscle strength (MVC; ~8%) with no impact of protein timing. Following 2 days of recovery, VIT increased maximal voluntary contraction and predicted VO2peak by ~10 and ~5%, respectively, with a moderate beneficial effect of IMM on predicted VO2peak (ES = 0.78). Conclusion: Successive days of simulated team sport exercise decreases markers of next-day performance capacity with no effect of protein timing on acute recovery. However, practical VIT increases muscle strength and aerobic capacity in as little as 5 days with the latter potentially enhanced by immediate post-exercise protein consumption.

13.
Actas urol. esp ; 44(10): 682-691, dic. 2020. graf, ilus, tab
Artículo en Español | IBECS | ID: ibc-198945

RESUMEN

CONTEXTO: La disección de los ganglios linfáticos pélvicos (DGLP) en el cáncer de próstata localizado es viable mediante un abordaje abierto, laparoscópico o asistido por robot. La información sobre la comparación de los 3 enfoques es escasa. OBJETIVO: Realizar una revisión para comparar la efectividad de los diferentes enfoques de la DGLP. Adquisición de la evidencia: Se realizó una búsqueda incluyendo las siguientes palabras: («disección de ganglios linfáticos pélvicos») o («linfadenectomía pélvica») y («francés» [Idioma] o «inglés» [Idioma]) y («1990» [Fecha-Publicación]: «3000» [Fecha-Publicación]) y prostatectomía [Título]). Finalmente, se incluyeron 29 artículos en la síntesis cualitativa. Síntesis de la evidencia: Al compararla con un abordaje abierto, la linfadenectomía pélvica laparoscópica en el cáncer de próstata es un procedimiento mínimamente invasivo con un tiempo operatorio relativamente corto, un sangrado mínimo, un nivel más bajo de dolor, una estancia hospitalaria más corta y menos complicaciones perioperatorias. Esta técnica es más rentable que el abordaje asistido por robot. CONCLUSIÓN: La linfadenectomía pélvica laparoscópica debe ser conocida e implementada por los urólogos para el tratamiento del cáncer de próstata localizado


CONTEXT: Pelvic lymph node dissection (PLND) in localized prostate cancer is feasible through an open, laparoscopic or robot-assisted approach. Data comparing the three approaches is sparse. OBJECTIVE: To perform a review in order to compare the effectiveness of the different PLND approaches. Acquisition of evidence: A search was performed including the following words: ("pelvic lymph node dissection") OR ("pelvic lymphadenectomy") AND ("French"[Language] OR "English"[Language]) AND ("1990"[Date-Publication]: "3000"[Date-Publication]) AND prostatectomy[Title]). Twenty-nine articles were finally included in the qualitative synthesis. Evidence synthesis: Laparoscopic pelvic lymph node dissection in prostate cancer is a minimally invasive procedure with a relatively short operative time, minimal blood loss, lower level of pain, shorter hospital stay, and fewer perioperative complications when compared to an open approach. This technique is more cost-effective than a robot-assisted approach. CONCLUSION: Concerning the treatment of localized prostate cancer, laparoscopic pelvic lymph node dissection should be learned and applied by urologists


Asunto(s)
Humanos , Masculino , Escisión del Ganglio Linfático/métodos , Neoplasias de la Próstata/cirugía , Laparoscopía/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Pelvis , Análisis Costo-Beneficio , Resultado del Tratamiento
14.
Actas Urol Esp (Engl Ed) ; 44(10): 682-691, 2020 Dec.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33069487

RESUMEN

CONTEXT: Pelvic lymph node dissection (PLND) in localized prostate cancer is feasible through an open, laparoscopic or robot-assisted approach. Data comparing the three approaches is sparse. OBJECTIVE: To perform a review in order to compare the effectiveness of the different PLND approaches. ACQUISITION OF EVIDENCE: A search was performed including the following words: ("pelvic lymph node dissection") OR ("pelvic lymphadenectomy") AND ("French"[Language] OR "English"[Language]) AND ("1990"[Date-Publication]: "3000"[Date-Publication]) AND prostatectomy[Title]). Twenty-nine articles were finally included in the qualitative synthesis. EVIDENCE SYNTHESIS: Laparoscopic pelvic lymph node dissection in prostate cancer is a minimally invasive procedure with a relatively short operative time, minimal blood loss, lower level of pain, shorter hospital stay, and fewer perioperative complications when compared to an open approach. This technique is more cost-effective than a robot-assisted approach. CONCLUSION: Concerning the treatment of localized prostate cancer, laparoscopic pelvic lymph node dissection should be learned and applied by urologists.


Asunto(s)
Laparoscopía , Escisión del Ganglio Linfático/métodos , Neoplasias de la Próstata/cirugía , Humanos , Metástasis Linfática , Masculino , Pelvis , Neoplasias de la Próstata/patología
15.
J Appl Physiol (1985) ; 129(1): 133-143, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32525432

RESUMEN

Postexercise protein ingestion can elevate rates of myofibrillar protein synthesis (MyoPS), mTORC1 activity, and mTOR translocation/protein-protein interactions. However, it is unclear if leucine-enriched essential amino acids (LEAA) can similarly facilitate intracellular mTOR trafficking in humans after exercise. The purpose of this study was to determine the effect of postexercise LEAA (4 g total EAAs, 1.6 g leucine) on acute MyoPS and mTORC1 translocation and signaling. Recreationally active men performed lower-body resistance exercise (5 × 8-10 leg press and leg extension) to volitional failure. Following exercise participants consumed LEAA (n = 8) or an isocaloric carbohydrate drink (PLA; n = 10). MyoPS was measured over 1.5-4 h of recovery by oral pulse of l-[ring-2H5]-phenylalanine. Phosphorylation of proteins in the mTORC1 pathway were analyzed via immunoblotting and mTORC1-LAMP2/WGA/Rheb colocalization via immunofluorescence microscopy. There was no difference in MyoPS between groups (LEAA = 0.098 ± 0.01%/h; PL = 0.090 ± 0.01%/h; P > 0.05). Exercise increased (P < 0.05) rpS6Ser240/244(LEAA = 35.3-fold; PLA = 20.6-fold), mTORSer2448(LEAA = 1.8-fold; PLA = 1.2-fold) and 4EBP1Thr37/46(LEAA = 1.5-fold; PLA = 1.4-fold) phosphorylation irrespective of nutrition (P > 0.05). LAT1 and SNAT2 protein expression were not affected by exercise or nutrient ingestion. mTOR-LAMP2 colocalization was greater in LEAA preexercise and decreased following exercise and supplement ingestion (P < 0.05), yet was unchanged in PLA. mTOR-WGA (cell periphery marker) and mTOR-Rheb colocalization was greater in LEAA compared with PLA irrespective of time-point (P < 0.05). In conclusion, the postexercise consumption of 4 g of LEAA maintains mTOR in peripheral regions of muscle fibers, in closer proximity to its direct activator Rheb, during prolonged recovery independent of differences in MyoPS or mTORC1 signaling compared with PLA ingestion. This intracellular localization of mTOR may serve to "prime" the kinase for future anabolic stimuli.NEW & NOTEWORTHY This is the first study to investigate whether postexercise leucine-enriched amino acid (LEAA) ingestion elevates mTORC1 translocation and protein-protein interactions in human skeletal muscle. Here, we observed that although LEAA ingestion did not further elevate postexercise MyoPS or mTORC1 signaling compared with placebo, mTORC1 peripheral location and interaction with Rheb were maintained. This may serve to "prime" mTORC1 for subsequent anabolic stimuli.


Asunto(s)
Aminoácidos , Entrenamiento de Fuerza , Aminoácidos Esenciales , Humanos , Leucina , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Músculo Esquelético/metabolismo , Proteína Homóloga de Ras Enriquecida en el Cerebro , Serina-Treonina Quinasas TOR
16.
J Nutr ; 150(3): 505-511, 2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31618421

RESUMEN

BACKGROUND: Dietary protein supports resistance exercise-induced anabolism primarily via the stimulation of protein synthesis rates. The indicator amino acid oxidation (IAAO) technique provides a noninvasive estimate of the protein intake that maximizes whole-body protein synthesis rates and net protein balance. OBJECTIVE: We utilized IAAO to determine the maximal anabolic response to postexercise protein ingestion in resistance-trained men. METHODS: Seven resistance-trained men (mean ± SD age 24 ± 3 y; weight 80 ± 9 kg; 11 ± 5% body fat; habitual protein intake 2.3 ± 0.6 g·kg-1·d-1) performed a bout of whole-body resistance exercise prior to ingesting hourly mixed meals, which provided a variable amount of protein (0.20-3.00 g·kg-1·d-1) as crystalline amino acids modeled after egg protein. Steady-state protein kinetics were modeled with oral l-[1-13C]-phenylalanine. Breath and urine samples were taken at isotopic steady state to determine phenylalanine flux (PheRa), phenylalanine excretion (F13CO2; reciprocal of protein synthesis), and net balance (protein synthesis - PheRa). Total amino acid oxidation was estimated from the ratio of urinary urea and creatinine. RESULTS: Mixed model biphasic linear regression revealed a plateau in F13CO2 (mean: 2.00; 95% CI: 1.62, 2.38 g protein·kg-1·d-1) (r2 = 0.64; P Ë‚ 0.01) and in net balance (mean: 2.01; 95% CI: 1.44, 2.57 g protein·kg-1·d-1) (r2 = 0.63; P Ë‚ 0.01). Ratios of urinary urea and creatinine concentrations increased linearly (r = 0.84; P Ë‚ 0.01) across the range of protein intakes. CONCLUSIONS: A breakpoint protein intake of ∼2.0 g·kg-1·d-1, which maximized whole-body anabolism in resistance-trained men after exercise, is greater than previous IAAO-derived estimates for nonexercising men and is at the upper range of current general protein recommendations for athletes. The capacity to enhance whole-body net balance may be greater than previously suggested to maximize muscle protein synthesis in resistance-trained athletes accustomed to a high habitual protein intake. This trial was registered at clinicaltrials.gov as NCT03696264.


Asunto(s)
Proteínas en la Dieta/administración & dosificación , Ejercicio Físico , Metabolismo , Ingesta Diaria Recomendada , Entrenamiento de Fuerza , Adulto , Pruebas Respiratorias , Creatinina/orina , Humanos , Masculino , Fenilalanina/análisis , Fenilalanina/orina , Urea/orina , Adulto Joven
18.
J Hum Nutr Diet ; 27 Suppl 2: 313-20, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23634993

RESUMEN

BACKGROUND: The high amounts of phytic acid present in diets from developing countries are considered as important inhibitors of zinc (Zn) absorption. The present study aimed to assess the fractional absorption of Zn from a meal containing common Brazilian foods using the stable isotope technique. METHODS: Twelve men, aged 19-42 years, were fed a healthy experimental diet comprising lettuce, tomato, French fries, steak with onions, rice, beans, papaya, orange, pineapple, and passion fruit juice. Each subject received one intravenous dose of enriched (70) Zn, and the lunch was extrinsically labelled with enriched (67) Zn. Urinary (67) Zn and (70) Zn enrichments were assessed by inductively coupled plasma mass spectrometry. RESULTS: The labelled meal phytate : Zn molar ratio was very divergent with respect to chemically determined and calculated data. Subjects presented a normal Zn nutritional status before and after the study. The mean Zn absorption from the labelled meal was 30% (range 11-47%). CONCLUSIONS: According to the World Health Organization parameters, the results denote a moderate/high Zn bioavailability in the evaluated meal, with a variability in the absorption percentage that is similar to other studies. The data show that a typical Brazilian meal, with an adequate energy amount and a balanced macronutrient distribution, presents a Zn bioavailability in accordance with the worldwide recommended standard.


Asunto(s)
Ácido Fítico/administración & dosificación , Zinc/farmacocinética , Administración Intravenosa , Adulto , Disponibilidad Biológica , Brasil , Países en Desarrollo , Dieta , Relación Dosis-Respuesta a Droga , Alimentos Orgánicos , Humanos , Absorción Intestinal/efectos de los fármacos , Masculino , Estado Nutricional , Ácido Fítico/efectos adversos , Adulto Joven , Zinc/sangre , Zinc/deficiencia
19.
Mar Pollut Bull ; 64(7): 1402-8, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22626623

RESUMEN

The West Indian manatee Trichechus manatus is threatened with extinction in Brazil, and this study focused on nondestructive blood samples analyzed for metals, polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), as well as biochemical and hematological biomarkers. Studied manatees were kept at Projeto Peixe-Boi headquarters in Pernambuco State, and at two natural areas in estuaries where they are released to the wild. Manatees kept at the natural estuary in Paraiba State have blood concentrations of Al, Pb, Cd, Sn that are 11, 7, 8 and 23 times greater, respectively, than the concentrations found in blood of animals from the same species in Florida, USA. An inhibition of butyrylcholinesterase in manatees kept at the two reintroduction sites in Alagoas and Paraiba States indicated possible exposure of the animals to cholinesterase inhibitor insecticides. PCBs and OCPs were not detected. Results from this study will help delineate conservation efforts in the region.


Asunto(s)
Monitoreo del Ambiente , Trichechus manatus/sangre , Contaminantes Químicos del Agua/sangre , Animales , Biomarcadores/sangre , Brasil , Butirilcolinesterasa/sangre , Metales/sangre , Bifenilos Policlorados/sangre , Contaminación Química del Agua/estadística & datos numéricos
20.
Environ Monit Assess ; 184(12): 7373-82, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22322405

RESUMEN

Over the last years, investigations on the increase of platinum (Pt), palladium (Pd), and rhodium (Rh) levels in urban environments of big cities all over the world - especially to catalytic converters emissions - have been grown up enormously. São Paulo City is the 6th largest megacity in the world having about 20 million inhabitants and an ever increasing seven million motor vehicle fleet. In spite of this, there has never been an investigation regarding Pt, Pd, and Rh levels in the city. In the present study, Pt, Pd, and Rh concentrations were determined in soils adjacent to seven main high-density traffic avenues in the metropolitan region of São Paulo City. Inductively coupled plasma mass spectrometry was employed - after ultrasound-assisted aqua regia leaching - as analytical technigue. The results showed concentration levels up to 378 ng g(-1) for Pd, 208 ng g(-1) for Pt, and 0.2 to 45 ng g(-1) for Rh. These levels are much higher than those considered for the geochemical background of soils, indicating a catalytic converter source. Due to the different Pt/Pd/Rh ratio in Brazilian automobile catalytic converters, lower levels of Pt/Pd ratios compared with other similar studies were observed. The obtained results are the first data for monitoring Pt, Pd, and Rh pollution in São Paulo City soils.


Asunto(s)
Monitoreo del Ambiente , Paladio/análisis , Platino (Metal)/análisis , Rodio/análisis , Contaminantes del Suelo/análisis , Brasil , Ciudades , Humanos , Vehículos a Motor , Suelo/química
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