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1.
Environ Geochem Health ; 45(12): 9215-9230, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37209325

RESUMO

Mining activity is one of the main sources to pollute soil, water and plants. An analysis of soil and plant samples around the Atrevida mining area in Catalonia (NE Spain) was preformed to determine potentially harmful elements (PHEs). Soil and plant samples were taken at eight locations around the mining area. The topsoil (0-15 cm) samples were analysed for physico-chemical properties by standard methods, by ICP-MS for Cd, Co, Cr, Cu, Fe, Ni, Pb and Zn, and were microwave-digested. Plant, root and shoot samples were digested separately, and heavy metals were analysed by AAS. Translocation factor (TF), biological concentration factor (BCF) and biological accumulation factor (BAF) were determined to assess the tolerance strategies developed by native species and to evaluate their potential for phytoremediation purposes. Soil pH was generally acid (5.48-6.72), with high soil organic matter (SOM) content and a sandy loamy or loamy texture. According to the agricultural soil values in southern Europe, our PHEs concentrations exceeded the toxicity thresholds. The highest root content of the most studied PHEs appeared in Thymus vulgaris L. and Festuca ovina L., while Biscutella laevigata L. accumulated more PHEs in shoots. The TF values were > 1 in B. laevigata L., but BAF obtained < 1, except Pb. B. laevigata L., and can be considered potentially useful for phytoremediation for having the capacity to restrict the accumulation of large PHEs amounts in roots and Pb translocation to shoots.


Assuntos
Metais Pesados , Poluentes do Solo , Solo/química , Espanha , Chumbo/toxicidade , Chumbo/análise , Poluentes do Solo/análise , Metais Pesados/toxicidade , Metais Pesados/análise , Plantas , Monitoramento Ambiental
2.
Nitric Oxide ; 134-135: 1-9, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36906115

RESUMO

BACKGROUND: Several studies have shown inorganic nitrate/nitrite to reduce blood pressure in both healthy subjects and hypertensive patients. An effect presumably caused through bioconversion to nitric oxide. However, studies on inorganic nitrate/nitrite have shown inconsistent results on renal functions such as GFR and sodium excretion. The current study investigated whether orally administered nitrate would decrease blood pressure and increase GFR and urinary sodium excretion. METHODS: In a randomized, placebo-controlled, double-blinded, crossover study, 18 healthy subjects received a daily dose of 24 mmol potassium nitrate and placebo (potassium chloride) during 4 days in a randomized order. Subjects also ingested a standardized diet and completed a 24-h urine collection. GFR was determined by the constant infusion technique and during GFR measurement, brachial blood pressure (BP) and central blood pressure (cBP), heart rate, and arterial stiffness were measured every half hour using the Mobil-O-Graph®. Blood samples was analyzed for nitrate, nitrite, cGMP, vasoactive hormones and electrolytes. Urine was analyzed for nitrate, nitrite, cGMP, electrolytes, ENaCγ, NCC, CrCl, CH2O and UO. RESULTS: No differences in GFR, blood pressure or sodium excretion were found between the treatments with potassium nitrate and placebo. However, both nitrate and nitrite levels in plasma and urine were significantly increased by potassium nitrate intake and the 24-h urinary excretion of sodium and potassium were stable, showing adherence to the standardized diet and the study medication. CONCLUSION: We found no decrease in blood pressure or increase in GFR and sodium excretion of 24 mmol potassium nitrate capsules as compared to placebo after 4 days of treatment. Healthy subjects may be able to compensate the effects of nitrate supplementation during steady state conditions. Future research should focus on long-term studies on the difference in response between healthy subjects and patients with cardiac or renal disease.


Assuntos
Nitratos , Nitritos , Humanos , Pressão Sanguínea , Nitratos/farmacologia , Estudos Cross-Over , Nitritos/farmacologia , Voluntários Saudáveis , Sódio , Rim/fisiologia , Método Duplo-Cego
3.
Sci Rep ; 13(1): 1853, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725876

RESUMO

Data acquired by a dense seismic network deployed in the Cerdanya basin (Eastern Pyrenees) is used to track the temporal and spatial evolution of meteorological events such as rainfall episodes or thunderstorms. Comparing seismic and meteorological data, we show that for frequencies above 40 Hz, the dominant source of seismic noise is rainfall and hence the amplitude of the seismic data can be used as a proxy of rainfall. The interstation distance of 1.5 km provides an unprecedented spatial resolution of the evolution of rainfall episodes along the basin. Two specific episodes, one dominated by stratiform rain and the second one dominated by convective rain, are analyzed in detail, using high resolution disdrometer data from a meteorological site near one of the seismic instruments. Seismic amplitude variations follow a similar evolution to radar reflectivity values, but in some stratiform precipitation cases, it differs from the radar-derived precipitation estimates in this region of abrupt topography, where radar may suffer antenna beam blockage. Hence, we demonstrate the added value of seismic data to complement other sources of information such as rain-gauge or weather radar observations to describe the evolution of ground-level rainfall fields at high spatial and temporal resolution. The seismic power and the rainfall intensity have an exponential relationship and the periods with larger seismic power are coincident. The time intervals with rain drops diameters exceeding 3.5 mm do not result in increased seismic amplitudes, suggesting that there is a threshold value from which seismic data are no longer proportional to the size of the drops. Thunderstorms can be identified by the recording of the sonic waves generated by thunders, with. Single thunders detected to distances of a few tens of kilometers. As the propagation of these acoustic waves is expected to be strongly affected by parameters as air humidity, temperature variations or wind, the seismic data could provide an excellent tool to investigate atmospheric properties variations during thunderstorms.

4.
Environ Geochem Health ; 45(12): 9469-9475, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36515754

RESUMO

There is mainly a lack of boron (B) in soils with low amounts of organic matter and in acidic and sandy soils. This is especially true in irrigated land or humid regions, where leaching can occur. The results from studying the amount of available B will reveal the status of B in the soil of a specific plot of land. The experimentation was performed as a controlled study using leaching columns. A container was placed at the end of the columns to collect the infiltrated water. Three treatments were performed by applying different amounts of biosolids (T40: 40,000 kg ha-1, T80: 80,000 kg ha-1, T120: 120,000 kg ha-1), as well as a blank test or control treatment (T0). We conclude that the mobility of B in soil was generally low despite the addition of organic matter and humidity to the soil. This is an indication that there is no clear risk of aquifers being contaminated with B or plants being impacted by toxicity due to this micronutrient.


Assuntos
Poluentes do Solo , Solo , Boro , Biossólidos , Agricultura , Micronutrientes , Poluentes do Solo/análise
5.
Environ Geochem Health ; 44(1): 7-14, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33159643

RESUMO

The precipitation of sparingly soluble calcium phosphate in calcareous soils decreases the bioavailability of macronutrients, which makes their addition by way of fertilisers necessary. Sludge resulting from treating urban wastewater does not only provide significant amounts of phosphorus, but also helps lower the pH, thus increasing its bioavailability. The loss of part of soil nutrients due to irrigation or rain can contaminate groundwater. In order to assess the movement of phosphorus, a experiment was conducted on percolation columns, to which different doses of wastes were applied. The pH decreased by as much as 0.89 units, as well as the assimilable and soluble P, in intervals of 20 cm of depth, obtaining maximum values of 254 mg P kg-1 and 1455 µg P kg-1 respectively, and the P present in the leached water collected, which did not surpass 95 µg PL-1. The intent was to learn which was the majoritarian inorganic formed crystalline phase that immobilised the movement of phosphorus through the percolation column. The results obtained by the diffraction of X-rays are not conclusive, although they point to the formation of octacalcium phosphate. The diffractograms of the studied samples have similar diffraction lines to those of apatites.


Assuntos
Fósforo , Solo , Disponibilidade Biológica , Biossólidos , Fósforo/análise , Espanha
6.
EJNMMI Res ; 11(1): 117, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34807325

RESUMO

PURPOSE: The purpose of this study is to compare dynamic and static whole-body (WB) [18F]NaF PET/CT scan methods used for analysis of bone plasma clearance in patients with chronic kidney disease-mineral and bone disorder (CKD-MBD). METHODS: Seventeen patients with CKD-MBD underwent a 60-min dynamic scan followed by a 30-min static WB scan. Tracer kinetics in four thoracic vertebrae were analysed using nonlinear regression and Patlak analysis using image-derived arterial input functions. The static WB scan was analysed using a simplified Patlak method requiring only a single data point in combination with a fixed y-intercept value (V0), both obtained using a semi-population function. The semi-population function was constructed by combining a previously derived population input function in combination with data from venous blood samples. Static WB scan analysis data, obtained from the semi-population input functions, was compared with paired data obtained using dynamic input functions. RESULTS: Bone plasma clearance (Ki) from Patlak analyses correlated well with nonlinear regression analysis, but Ki results using Patlak analysis were lower than Ki results using nonlinear regression analysis. However, no significant difference was found between Ki obtained by static WB scans and Ki obtained by dynamic scans using nonlinear regression analysis (p = 0.29). CONCLUSION: Bone plasma clearance measured from static WB scans correlates with clearance data measured by dynamic analysis. Static [18F]NaF PET/CT scans can be applied in future studies to measure Ki in patients with CKD-MBD, but the results should not be compared uncritically with results obtained by dynamic scan analysis.

7.
BMC Nephrol ; 22(1): 111, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33771116

RESUMO

BACKGROUND: Isotonic saline (IS) is widely used to secure perioperative cardiovascular stability. However, the high amount of chloride in IS can induce hyperchloremic acidosis. Therefore, IS is suspected to increase the risk of acute kidney injury (AKI). Biomarkers may have potential as indicators. METHODS: In a double-blinded, placebo-controlled study, 38 patients undergoing primary uncemented hip replacement were randomized to IS or PlasmaLyte (PL). Infusion was given during surgery as 15 ml/kg the first hour and 5 ml/kg the following two hours. Urinary samples were collected upon admission and the day after surgery. As surgery was initiated, urine was collected over the course of 4 h. Hereafter, another urine collection proceeded until the morning. Urine was analyzed for markers of AKI neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1). Arterious and venous blood samples for measurements of pH and plasma electrolytes including chloride (p-Cl) were collected as surgery was initiated, at the end of surgery and the following morning. RESULTS: IS induced an increase in p-Cl (111 ± 2 mmol/L after IS and 108 ± 3 after PL, p = 0.004) and a decrease in pH (7.39 ± 0.02 after IS and 7.43 ± 0.03 after PL, p = 0.001). Urinary NGAL excretion increased in both groups (ΔNGAL: 5.5 [4.1; 11.7] µg/mmol creatinine p = 0.004 after IS vs. 5.5 [2.1;9.4] µg/mmol creatinine after PL, p < 0.001). No difference was found between the groups (p = 0.839). Similarly, urinary KIM-1 excretion increased in both groups (ΔKIM-1: IS 115.8 [74.1; 156.2] ng/mmol creatinine, p < 0.001 vs. PL 152.4 [120.1; 307.9] ng/mmol creatinine, p < 0.001). No difference between the groups (p = 0.064). FENa increased (1.08 ± 0.52% after IS and 1.66 ± 1.15% after PL, p = 0.032). ENaC excretion was different within groups (p = 0.019). CONCLUSION: A significantly higher plasma chloride and a lower pH was present in the group receiving isotonic saline. However, u-NGAL and u-KIM-1 increased significantly in both groups after surgery despite absence of changes in creatinine. These results indicate that surgery induced subclinical kidney injury. Also, the IS group had a delayed sodium excretion as compared to the PL group which may indicate that IS affects renal sodium excretion differently from PL. TRIAL REGISTRATION: ClinicalTrials.gov Identifier:  NCT02528448 , 19/08/2015.


Assuntos
Injúria Renal Aguda/etiologia , Artroplastia de Quadril/efeitos adversos , Receptor Celular 1 do Vírus da Hepatite A , Lipocalina-2/urina , Solução Salina/administração & dosagem , Sódio/urina , Injúria Renal Aguda/urina , Idoso , Biomarcadores/urina , Cloretos/sangue , Método Duplo-Cego , Feminino , Gluconatos/administração & dosagem , Humanos , Concentração de Íons de Hidrogênio , Cloreto de Magnésio/administração & dosagem , Masculino , Pessoa de Meia-Idade , Cloreto de Potássio/administração & dosagem , Acetato de Sódio/administração & dosagem , Cloreto de Sódio/administração & dosagem
8.
Int J Nephrol ; 2020: 4108418, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33343937

RESUMO

The final dilution of urine is regulated via aquaporin-2 water channels in the distal part of the nephron. It is unclear whether urine dilution ability in autosomal dominant polycystic kidney disease patients (ADPKD patients) differs from other patients with similar degree of impaired renal function (non-ADPKD patients). The purpose of this case control study was to measure urine dilution ability in ADPKD patients compared to non-ADPKD patients and healthy controls. Methods. Eighteen ADPKD, 16 non-ADPKD patients (both with chronic kidney disease, stage I-IV), and 18 healthy controls received an oral water load of 20 ml/kg body weight. Urine was collected in 7 consecutive periods. We measured free water clearance (CH2O), urine osmolality, urine output, fractional excretion of sodium, urine aquaporin2 (u-AQP2), and urine epithelial sodium channel (u-ENaC). Blood samples were drawn four times (at baseline, 2 h, 4 h, and 6 hours after the water load) for analyses of plasma osmolality, vasopressin, renin, angiotensin II, and aldosterone. Brachial and central blood pressure was measured regularly during the test. Results. The three groups were age and gender matched, and the patient groups had similar renal function. One hour after water load, the ADPKD patients had an increased CH2O compared to non-ADPKD patients (2.97 ± 2.42 ml/min in ADPKD patients vs. 1.31 ± 1.50 ml/min in non-ADPKD patients, p0.029). The reduction in u-AQP2 and u-ENaC occurred earlier in ADPKD than in non-ADPKD patients. Plasma concentrations of vasopressin, renin, angiotensin II, and aldosterone and blood pressure measurements did not show any differences that could explain the deviation in urine dilution capacity between the patient groups. Conclusions. ADPKD patients had a higher CH2O than non-ADPKD patients after an oral water load, and u-AQP2 and u-ENaC were more rapidly reduced than in non-ADPKD patients. Thus, urine-diluting capacity may be better preserved in ADPKD patients than in non-ADPKD patients.

9.
BMC Nephrol ; 21(1): 379, 2020 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-32867720

RESUMO

BACKGROUND: Concentration of the urine is primarily regulated via vasopressin dependent aquaporin-2 water channels in the apical membrane of kidney principal cells. It is unclear whether urine concentration ability in ADPKD differs from other patients with similar degree of impaired renal function (non-ADPKD patients). The purpose of this case control study was to measure urine concentration ability in ADPKD patients compared to non-ADPKD patients and healthy controls. METHODS: A seventeen hour long water deprivation test was carried out in 17 ADPKD patients (CKD I-IV), 16 non-ADPKD patients (CKD I-IV), and 18 healthy controls. Urine was collected in 4 consecutive periods during water deprivation (12 h, 1 h, 2 h and 2 h, respectively) and analyzed for osmolality (u-Osm), output (UO), fractional excretion of sodium (FENa), aquaporin2 (u-AQP2) and ENaC (u-ENaC). Blood samples were drawn trice (after 13-, 15-, and 17 h after water deprivation) for analyses of osmolality (p-Osm), vasopressin (p-AVP), and aldosterone (p-Aldo). RESULTS: U-Osm was significantly lower and FENa significantly higher in both ADPKD patients and non-ADPKD patients compared to healthy controls during the last three periods of water deprivation. During the same periods, UO was higher and secretion rates of u-AQP2 and u-ENaC were lower and at the same level in the two groups of patients compared to controls. P-AVP and p-Osm did not differ significantly between the three groups. P-Aldo was higher in both groups of patients than in controls. CONCLUSIONS: Urine concentration ability was reduced to the same extent in patients with ADPKD and other chronic kidney diseases with the same level of renal function compared to healthy controls. The lower urine excretion of AQP2 and ENaC suggests that the underlying mechanism may be a reduced tubular response to vasopressin and aldosterone. TRIAL REGISTRATION: Current Controlled Trial NCT04363554 , date of registration: 20.08.2017.


Assuntos
Capacidade de Concentração Renal/fisiologia , Rim Policístico Autossômico Dominante/fisiopatologia , Insuficiência Renal Crônica/fisiopatologia , Adulto , Idoso , Aldosterona/sangue , Aquaporina 2/urina , Estudos de Casos e Controles , Canais Epiteliais de Sódio/urina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Rim Policístico Autossômico Dominante/metabolismo , Eliminação Renal , Insuficiência Renal Crônica/metabolismo , Índice de Gravidade de Doença , Sódio/urina , Vasopressinas/sangue , Privação de Água
10.
BMC Nephrol ; 20(1): 200, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159750

RESUMO

BACKGROUND: Chloride is speculated to have nephrotoxic properties. In healthy subjects we tested the hypothesis that acute chloride loading with 3% saline would induce kidney injury, which could be prevented with the loop-diuretic furosemide. METHODS: The study was designed as a randomized, placebo-controlled, crossover study. Subjects were given 3% saline accompanied by either placebo or furosemide. Before, during and after infusion of 3% saline we measured glomerular filtration rate (GFR), fractional excretion of sodium (FENa), urinary chloride excretion (u-Cl), urinary excretions of aquaporin-2 (u-AQP2) and epithelial sodium channels (u-ENaCγ), neutrophil gelatinase-associated lipocalin (u-NGAL) and kidney injury molecule-1 (u-KIM-1) as marker of kidney injury and vasoactive hormones: renin (PRC), angiotensin II (p-AngII), aldosterone (p-Aldo) and arginine vasopressin (p-AVP). Four days prior to each of the two examinations subjects were given a standardized fluid and diet intake. RESULTS: After 3% saline infusion u-NGAL and KIM-1 excretion increased slightly (u-NGAL: 17 ± 24 during placebo vs. -7 ± 23 ng/min during furosemide, p = 0.039, u-KIM-1: 0.21 ± 0.23 vs - 0.06 ± 0.14 ng/ml, p <  0.001). The increase in u-NGAL was absent when furosemide was given simultaneously, and the responses in u-NGAL were not significantly different from placebo control. Furosemide changed responses in u-KIM-1 where a delayed increase was observed. GFR was increased by 3% saline but decreased when furosemide accompanied the infusion. U-Na, FENa, u-Cl, and u-osmolality increased in response to saline, and the increase was markedly pronounced when furosemide was added. FEK decreased slightly during 3% saline infusion, but simultaneously furosemide increased FEK. U-AQP2 increased after 3% saline and placebo, and the response was further increased by furosemide. U-ENaCγ decreased to the same extent after 3% saline infusion in the two groups. 3% saline significantly reduced PRC, p-AngII and p-Aldo, and responses were attenuated by furosemide. p-AVP was increased by 3% saline, with a larger increase during furosemide. CONCLUSION: This study shows minor increases in markers of kidney injury after 3% saline infusion Furosemide abolished the increase in NGAL and postponed the increase in u-KIM-1. The clinical importance of these findings needs further investigation. TRIAL REGISTRATION: (EU Clinical trials register number: 2015-002585-23 , registered on 5th November 2015).


Assuntos
Injúria Renal Aguda , Biomarcadores/urina , Cloretos , Furosemida , Rim , Solução Salina Hipertônica , Injúria Renal Aguda/sangue , Injúria Renal Aguda/induzido quimicamente , Adulto , Aldosterona/urina , Aquaporina 2/urina , Cloretos/efeitos adversos , Cloretos/farmacocinética , Feminino , Furosemida/administração & dosagem , Furosemida/efeitos adversos , Taxa de Filtração Glomerular/efeitos dos fármacos , Voluntários Saudáveis , Humanos , Rim/metabolismo , Rim/fisiopatologia , Lipocalina-2/urina , Masculino , Avaliação de Resultados em Cuidados de Saúde , Soluções Farmacêuticas , Eliminação Renal/efeitos dos fármacos , Solução Salina Hipertônica/administração & dosagem , Solução Salina Hipertônica/efeitos adversos , Inibidores de Simportadores de Cloreto de Sódio e Potássio/administração & dosagem , Inibidores de Simportadores de Cloreto de Sódio e Potássio/efeitos adversos
11.
J Hum Hypertens ; 31(2): 93-98, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27334521

RESUMO

Telemonitoring of home blood pressure measurements (TBPM) is a new and promising supplement to diagnosis, control and treatment of hypertension. We wanted to compare the outcome of antihypertensive treatment based on TBPM and conventional monitoring of blood pressure. Participants were recruited from a prevalence study among citizens aged 55-64 years in the municipality of Holstebro, Denmark. The study was a randomized, controlled, unblinded 3 months' trial. In the intervention group, antihypertensive treatment was based on TBPM with transmission of the measurements and subsequent communication by telephone or e-mail. In the control group, patients received usual care. Primary outcome was reduction in daytime ambulatory blood pressure measurements (ABPM) from baseline to 3 months' follow-up. Of 375 participants randomized, primary outcome data were available for 356 (95%). In both groups, daytime ABPM decreased significantly. The decrease in daytime ABPM in the intervention group was systolic/diastolic, -8±12/-4±7 mm Hg. This did not differ significantly from the control group's -8±13/-4±8 mm Hg. An equal number of participants obtained normal daytime ABPM, in the intervention group 17% (31/175) versus control 21% (37/181), P=0.34. We found that both TBPM patients and controls achieved a significant blood pressure reduction in this randomized, controlled, unblinded 3-month trial. We found no difference in blood pressure reduction or number of patients reaching blood pressure goals. Further information and education of some general practitioners seem to be relevant regarding blood pressure management and control of hypertension.


Assuntos
Monitorização Ambulatorial da Pressão Arterial/estatística & dados numéricos , Telemedicina/estatística & dados numéricos , Monitorização Ambulatorial da Pressão Arterial/instrumentação , Humanos , Pessoa de Meia-Idade
12.
Neth Heart J ; 23(12): 592-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26449240

RESUMO

BACKGROUND: Gender and complete revascularisation are known to affect mortality. The objective of this study was to analyse a gender difference in mortality with respect to complete revascularisation for multivessel disease after primary percutaneous coronary intervention (PPCI) in ST-elevation myocardial infarction (STEMI) patients. METHOD: In a prospective consecutive cohort of 1472 patients presenting with STEMI for PPCI, between January 2006 and January 2010, 832 patients with multivessel disease were analysed. The primary outcome was long-term mortality. RESULTS: Median follow-up was 3.3 ± 1.2 years. Complete revascularisation was performed less in females than in males (30 vs. 38 %; p = 0.04). At PPCI, women (27 %, n = 221) were ± 10 years older (p = 0.001), had more hypertension, renal failure and symptoms of heart failure (all p < 0.01). Cumulative long-term mortality with incomplete revascularisation was higher in females (F: 30 vs. M: 15 %, p = 0.01). After adjustment for baseline characteristics, complete revascularisation (0.84; 95 % CI 0.54-1.32) and gender (1.11; 95 % CI 0.73-1.69) lost significance. Also the gender-by-complete revascularisation interaction was not significant at long term. In women, age under 60 years independently predicted higher mortality (HR 10.09; 95 % CI 3.08-33.08; p < 0.001). CONCLUSION: In STEMI patients with multivessel disease at PPCI, women under the age of 60 years had higher mortality, but in women older than 60 years comorbidity impacted the outcome of revascularisation strategy in the long term.

13.
J Card Fail ; 19(11): 776-85, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24263123

RESUMO

BACKGROUND: The significance of basal renal nitric oxide (NO) availability in the regulation of renal perfusion and sodium excretion in human congestive heart failure (CHF) has not been described previously. METHODS AND RESULTS: We studied the effects of acute systemic NO synthesis inhibition with N(G)-monomethyl-L-arginine (L-NMMA) in 12 patients with CHF and 10 healthy control subjects (CON) in a randomized placebo-controlled study. Effect parameters were renal plasma flow (RPF), renal vascular resistance (RVR), glomerular filtration rate (GFR), urine sodium excretion and plasma levels of vasoactive hormones. L-NMMA was associated with a significant decrease in RPF (CON-LNMMA: -13 ± 3% [P = .014]; CHF-LNMMA: -17 ± 7% [P = .017]) and a profound increase in RVR in both CHF and CON (CON-LNMMA: +26 ± 6% [P = .009]; CHF-LNMMA: +37 ± 70% [P = .005]). Significant decreases in sodium excretion were found in both CHF-LNMMA and CON-LNMMA. Relative changes from baseline were not statistically different between CHF-LNMMA and CON-LNMMA. After L-NMMA, RPF values correlated inversely with plasma aldosterone in CHF-LNMMA (P = .01). L-NMMA induced an increase in A-type natriuretic peptide (ANP) only in CHF-LNMMA (+18 ± 8%; P = .035), which correlated significantly with basal ANP levels (P = .034). CONCLUSIONS: There was no difference in the renal response to L-NMMA in CHF vs CON, suggesting that the impact of NO on renal perfusion and sodium excretion is maintained in stable CHF. We suggest that NO influences the release of ANP during high levels of atrial stretch in CHF.


Assuntos
Taxa de Filtração Glomerular/fisiologia , Insuficiência Cardíaca/sangue , Rim/irrigação sanguínea , Rim/metabolismo , Óxido Nítrico/sangue , Resistência Vascular/fisiologia , Idoso , Aldosterona/sangue , Fator Natriurético Atrial/sangue , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo/fisiologia , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/urina , Humanos , Rim/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/urina , Resistência Vascular/efeitos dos fármacos , ômega-N-Metilarginina/farmacologia , ômega-N-Metilarginina/uso terapêutico
14.
Scand J Med Sci Sports ; 20 Suppl 1: 50-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20136765

RESUMO

The present study examined the cardiac effects of football training and running for inactive pre-menopausal women by standard echocardiography and tissue Doppler imaging. Thirty-seven subjects were randomized to two training groups (football: FG; n=19; running; RG; n=18) training 1 h with equal average heart rates twice a week for 16 weeks and compared with a matched inactive control group (CG; n=10). During the training period, left ventricular end-diastolic volume increased by 13% in FG and 11% in RG (P<0.05). Left ventricular posterior wall thickness increased in FG from 8.5+/-1.4 to 9.0+/-1.3 mm (P<0.05). Right ventricle diameter increased by 12% in FG and 10% in RG (P<0.05). Tissue Doppler imaging demonstrated increased left ventricular systolic and diastolic performances in both training groups. Peak systolic velocity increased by 26% in FG and 17% in RG (P<0.05) and left ventricular longitudinal displacement increased in both groups by 13% (P<0.05). Isovolumetric relaxation time decreased significantly more in FG than in RG (26% vs 14%, respectively P<0.05). In conclusion, 16 weeks of football and running exercise training induced significant changes of cardiac dimensions and had favorable effects on both left ventricular systolic and diastolic function. These training-induced cardiac adaptations appeared to be more consistent after football training compared with running.


Assuntos
Pressão Sanguínea/fisiologia , Exercício Físico/fisiologia , Testes de Função Cardíaca , Aptidão Física/fisiologia , Comportamento Sedentário , Ecocardiografia Doppler , Feminino , Humanos , Corrida/fisiologia , Futebol/fisiologia
15.
J Clin Pharmacol ; 50(7): 816-22, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20056802

RESUMO

Statins improve cardiovascular survival in both nondiabetic and diabetic patients, but diabetic patients benefit more, in both primary and secondary prevention. Statins seem to have multiple effects beyond cholesterol lowering, that is, pleiotropic effects that may include changes in renal function. This study tests the hypothesis that acute treatment with atorvastatin may change glomerular filtration rate, tubular function, vasoactive hormones, blood pressure, and pulse rate in patients with type 2 diabetes. In an acute, randomized, placebo-controlled, double-blinded, crossover trial, the effects of atorvastatin on renal function, vasoactive hormones, blood pressure, and pulse rate are measured in 21 patients with type 2 diabetes. Patients are randomized to either 2 doses of atorvastatin 80 mg or placebo before 2 different study days. Treatment with atorvastatin induces a significant reduction in fractional sodium excretion compared with placebo, and sodium clearance tends to be reduced. No significant differences in glomerular filtration rate, albumin/creatinine ratio, vasoactive hormones, and blood pressure by acute treatment with atorvastatin are found in diabetic patients. Acute treatment with atorvastatin reduces renal fractional sodium excretion in patients with type 2 diabetes. No changes are measured in glomerular filtration rate, albumin/creatinine ratio, vasoactive hormones, and blood pressure.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatologia , Taxa de Filtração Glomerular/efeitos dos fármacos , Ácidos Heptanoicos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Túbulos Renais/efeitos dos fármacos , Hormônios Peptídicos/fisiologia , Pirróis/farmacologia , Adulto , Idoso , Atorvastatina , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sódio/urina
16.
Scand J Clin Lab Invest ; 69(3): 323-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19051099

RESUMO

OBJECTIVE: Improved cardiovascular survival during statin treatment might be due to effects in addition to cholesterol lowering. We hypothesize that sodium intake affects renal function and vasoactive hormones in atorvastatin-treated healthy subjects. METHODS: In a randomized, placebo-controlled, double-blind, crossover study we measured the effect of a moderate change in sodium intake on glomerular filtration rate (GFR), blood pressure (BP), renal tubular function, plasma concentrations of vasoactive hormones and urinary excretion of aquaporin-2 (u-AQP2) in 22 healthy subjects. The subjects were randomized to standardized fluid intake and diet corresponding to the need for calories in the 4 days before each of the 2 examination days. In one of the periods they were randomized to receive sodium chloride tablets (2 g) thrice daily for 4 days. Two doses of atorvastatin (80 mg) were given; one at 2200 h the evening before the study day, the other at 0830 h in the morning. RESULTS: 24-h urinary sodium excretion increased by 23%. GFR and BP were unchanged. Sodium clearance, fractional excretion of sodium and u-AQP2 increased, whereas free water clearance decreased during high sodium intake. PRC and aldosterone were suppressed during the high sodium diet. CONCLUSIONS: A change in dietary sodium intake of approximately 100 mmol daily does not change GFR and BP in atorvastatin-treated healthy men. The lack of change in BP might reflect that the subjects studied were not sodium sensitive, or that atorvastatin treatment modified sodium sensitivity.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Taxa de Filtração Glomerular/efeitos dos fármacos , Ácidos Heptanoicos/farmacologia , Pirróis/farmacologia , Sódio/farmacologia , Adulto , Aldosterona/sangue , Angiotensina II/sangue , Aquaporina 2/urina , Atorvastatina , Fator Natriurético Atrial/sangue , Feminino , Humanos , Testes de Função Renal , Lítio/farmacocinética , Masculino , Peptídeo Natriurético Encefálico/sangue , Renina/sangue , Sódio/farmacocinética , Vasopressinas/sangue
17.
Hernia ; 12(5): 483-91, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18483783

RESUMO

BACKGROUND: The main reason for hospital stay after laparoscopic ventral hernia repair (LVHR) is probably pain, which also causes a lengthening of the patient's time to assume normal daily activities and work. It is likely that titanium tacks may be the main contributing factor to early (and maybe chronic) pain after LVHR. Therefore, non-invasive and patient-friendly mesh fixation methods must be considered. The present study was designed to investigate the technical applicability, safety and effect of Tisseel for intraperitoneal mesh fixation. METHODS: Nine 40-kg Danish Landrace female pigs had two pieces of MotifMESH and two pieces of Proceed mesh fixed in the intraperitoneal position by a laparoscopic technique. The two pieces of the same mesh were fixed with fibrin glue (Tisseel) and titanium tacks, respectively. All pigs were euthanised on the 30th postoperative day and the mesh-tissue samples were tested for strength of ingrowth (peel test), adhesion formation, mesh shrinkage and examined for histological alterations. RESULTS: No meshes were displaced from their initial position at autopsy, but we observed two cases of mesh folding that could have resulted in hernia recurrence in real patients. There were no significant differences in the strength of ingrowth between different mesh types or fixation methods, measured as peel work per area of mesh (J/m2) and peak force per width of mesh (Nmax/cm). The Proceed mesh shrank by 11% compared to 4% for the MotifMESH mesh (p = 0.002). There was no difference in the grade of adhesions (%) between fixation methods (p = 0.794) or different mesh types (p = 0.296). In the same fashion, there was no difference in the strength of adhesions (grades 0-4) between the two fixation methods or different mesh types (p > 0.5, chi2 test). There was no significant difference in the formation of fibrosis or inflammation between the different meshes or fixation methods. All samples showed significant foreign-body reaction with giant cells. CONCLUSION: Our results suggest that the laparoscopic fixation of an intraperitoneal mesh with Tisseel is safe and technically feasible in a pig model. There is still no evidence that fibrin-sealing alone is appropriate for intraperitoneal mesh fixation in hernia repair, but the technique might become an alternative or supplement to mechanical mesh fixation. Until then, further experimental research in animal hernia models with larger meshes is needed, especially with a focus on mesh folding and displacement.


Assuntos
Materiais Biocompatíveis , Adesivo Tecidual de Fibrina/administração & dosagem , Hérnia Ventral/cirurgia , Laparoscopia/métodos , Adesivos Teciduais/administração & dosagem , Titânio , Animais , Modelos Animais de Doenças , Estudos de Viabilidade , Feminino , Modelos Animais , Telas Cirúrgicas , Suínos
18.
Environ Int ; 33(4): 502-4, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17169426

RESUMO

The major risks due to metal pollution of sediments consist of leaching to groundwater and potential toxicity to animals and/or plants. The objective of this study was to evaluate by means of an ecotoxicological approach the effects of the addition of cutting marble sludges on the mobile metal fraction of sediments polluted with heavy metals. The study was carried out on two sediments derived from mining activities in Portman Bay (SE, Spain) polluted by heavy metals. These sediments were mixed with sludges left after the cutting of marble. The results obtained by leaching experiments showed that the addition of marble cutting sludge, consisting mainly of carbonates, to a heavy-metal polluted sediment produces a decrease of available metal forms. The carbonate content seems to play a role in chemical stabilisation of metals and in a decrease of toxicity of sediments. The leached solutions have a non-toxic effect. The mild remediation by addition of sludge has moreover effects to long term.


Assuntos
Poluentes Ambientais/toxicidade , Recuperação e Remediação Ambiental/métodos , Indústrias , Metais Pesados/toxicidade , Esgotos , Sedimentos Geológicos/química , Espanha , Espectrofotometria Atômica , Difração de Raios X
19.
Scand J Clin Lab Invest ; 66(1): 55-66, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16464787

RESUMO

OBJECTIVE: Patients with chronic heart failure (CHF) have decreased ability to excrete water and increased urinary excretion of aquaporin-2 (U-AQP2). The natriuretic and diuretic effects of furosemide are antagonized by an increased reabsorption of sodium and water in the collecting ducts. It is unknown whether aquaporin-2 (AQP2) renal water channels are involved in this compensatory reabsorption. We tested the hypothesis that U-AQP2 increases after a single intravenous dose of furosemide in CHF patients. MATERIAL AND METHODS: In a randomized, single-blind, placebo-controlled, crossover study, we measured the effect of furosemide (80 mg) on U-AQP2, urine volume, free water clearance (C(H2O)) and fractional excretion of sodium (FE(Na)) in 12 CHF patients. Plasma concentrations of vasopressin (AVP), renin (PRC), angiotensin II (Ang II), aldosterone (Aldo), atrial (ANP) and brain natriuretic peptides (BNP) were measured during the study. U-AQP2 and hormones were determined by radioimmunoassays. RESULTS: Furosemide increased U-AQP2 (140 %), urine volume (280 %), C(H2O) (95 %) and FE(Na) by a factor of 15 (p<0.008 for all), and also AVP (51 %), PRC, Ang II (86 %) and Aldo (59 %) (p<0.021 for all). ANP and BNP did not change. CONCLUSIONS: In CHF, furosemide increased the vasopressin level, which stimulated water reabsorption via the APQ2 water channels. This is most likely a compensatory phenomenon in addition to the increase in the renin-angiotensin system to prevent excess loss of sodium and water. However, both these effects were overridden by the effect of furosemide, as shown by increased free water clearance and sodium excretion.


Assuntos
Aquaporina 2/urina , Furosemida/uso terapêutico , Insuficiência Cardíaca/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiotensina II/sangue , Arginina Vasopressina/sangue , Fator Natriurético Atrial/sangue , Pressão Sanguínea/efeitos dos fármacos , Doença Crônica , Estudos Cross-Over , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Natriurese/efeitos dos fármacos , Peptídeo Natriurético Encefálico/sangue , Renina/sangue
20.
Scand J Clin Lab Invest ; 65(3): 249-61, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16095054

RESUMO

OBJECTIVE: Furosemide inhibits renal sodium and chloride reabsorption in the loop of Henle. A compensatory increased reabsorption of sodium and water takes place in the collecting duct. It is not known whether aquaporin-2 (AQP2) renal water channels are involved in this compensatory reabsorption. In animals, dihydropyridine derivatives of calcium channel blockers down-regulate AQP2 in the collecting duct, but the effect has not been studied in humans. We sought to test the hypotheses that urinary excretion of aquaporin-2 (U-AQP2) increases after a single intravenous dose of furosemide, and that U-AQP2 decreases after a single oral dose of felodipine. MATERIAL AND METHODS: In two randomized, single-blind, placebo-controlled, cross-over studies, we measured the effect of furosemide and felodipine on U-AQP2, urine volume, free water clearance (CH2O), and fractional excretion of sodium (FENa) in 13 healthy subjects in each study. Plasma concentrations of vasopressin (AVP), renin (PRC), angiotensin II (ang II), aldosterone (aldo), atrial (ANP), and brain natriuretic peptides (BNP) were measured during the study. Glomerular filtration rate (GFR) was measured by constant infusion technique. U-AQP2 and hormones were determined by radioimmunoassay. RESULTS: Furosemide treatment increased U-AQP2 (202%), urine volume (214%), and FENa by a factor of 11, (p < 0.001 for all), whereas CH2O and GFR were unchanged. After treatment with placebo, no differences were seen. Furosemide treatment increased AVP (18%), PRC (60%), ang II (100%), and aldo (98%) (p < 0.032); ANP was decreased by 29% (p < 0.001), whereas there was no change in BNP. The hormones were unchanged after placebo except for a minor decrease in ANP after placebo. Felodipine tended to increase U-AQP2, to decrease CH2O and urine volume and GFR, and to increase FENa, but the effect was not significantly different from placebo. Felodipine increased PRC (82%) (p < 0.003) and ang II, but decreased aldo, and increased AVP. After placebo, PRC was unchanged, whereas ang II, aldo and AVP were changed as after felodipine. CONCLUSIONS: Furosemide treatment increased U-AQP2, AVP, and the activity of the renin-angiotensin-aldosterone system. These changes are most likely compensatory phenomena, which prevent an excess loss of sodium and water. Felodipine tended to increase U-AQP2.


Assuntos
Aquaporinas/urina , Felodipino/farmacologia , Furosemida/farmacologia , Adulto , Idoso , Aquaporina 2 , Peso Corporal/efeitos dos fármacos , Felodipino/metabolismo , Feminino , Furosemida/metabolismo , Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Plasma/química , Plasma/efeitos dos fármacos
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