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1.
BMC Ecol ; 18(1): 45, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30400929

RESUMO

BACKGROUND: Rehabilitation of degraded rangelands through the establishment of enclosures (fencing grazing lands) is believed to improve soil quality and livelihoods, and enhance the sustainability of rangelands. Grazing dominated enclosure (GDE) and contractual grazing enclosure (CGE) are the common enclosure management systems in West Pokot County, Kenya. Under CGE, a farmer owning few animals leases the enclosure to households with relatively more livestock, while GDE is where the livestock utilizing the enclosure are purely owned by the farmer. Livestock management in both systems is via the free-range system. This study evaluated the effect of enclosure management on total soil organic carbon (SOC), particulate organic carbon (POC) and microbial biomass carbon (MBC) and nitrogen (MBN) as key indicators of soil degradation at 0-40 cm depth. The two enclosure systems were selected based on three age classes (3-10, 11-20 and > 20 years since establishment) (n = 3). The adjacent open grazing area (OGR) was used as a reference (n = 9). RESULTS: Relative to OGR, the pasture enclosures significantly decreased soil bulk density and increased the concentrations of total organic C, POC, MBC and MBN compared to the degraded OGR (P < 0.001). Significantly higher concentrations of POC and MBC was recorded in GDE than CGE (P = 0.01). The POC accounted for 24.5-29.5% of the total SOC. MBC concentrations ranged from 32.05 ± 7.25 to 96.63 ± 5.31 µg C g-1 of soil in all grazing systems, and was positively correlated with total SOC and POC (P < 0.001). The proportional increase in POC and MBC was higher in GDE (56.6 and 30.5% respectively) compared to CGE (39.2 and 13.9% for POC and MBC respectively). CONCLUSIONS: This study demonstrated that controlling livestock grazing through the establishment of pasture enclosures is the key strategy to enhance total SOC, POC, MBC, and MBN in degraded rangelands; a precondition for improving soil quality. Therefore, the establishment of enclosures is an effective restoration approach to restore degraded soils in semi-arid rangelands.


Assuntos
Carbono/análise , Pradaria , Material Particulado/análise , Microbiologia do Solo , Solo/química , Biomassa , Quênia
2.
Sci Rep ; 6: 21930, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26908158

RESUMO

Water scarcity contributes to the poverty of around one-third of the world's people. Despite many benefits, tree planting in dry regions is often discouraged by concerns that trees reduce water availability. Yet relevant studies from the tropics are scarce, and the impacts of intermediate tree cover remain unexplored. We developed and tested an optimum tree cover theory in which groundwater recharge is maximized at an intermediate tree density. Below this optimal tree density the benefits from any additional trees on water percolation exceed their extra water use, leading to increased groundwater recharge, while above the optimum the opposite occurs. Our results, based on groundwater budgets calibrated with measurements of drainage and transpiration in a cultivated woodland in West Africa, demonstrate that groundwater recharge was maximised at intermediate tree densities. In contrast to the prevailing view, we therefore find that moderate tree cover can increase groundwater recharge, and that tree planting and various tree management options can improve groundwater resources. We evaluate the necessary conditions for these results to hold and suggest that they are likely to be common in the seasonally dry tropics, offering potential for widespread tree establishment and increased benefits for hundreds of millions of people.

3.
Int J Obes (Lond) ; 33(4): 408-17, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19290010

RESUMO

OBJECTIVE: To assess the efficacy of a school-based intervention programme to reduce the prevalence of overweight in 6 to 10-year-old children. DESIGN: Cluster-randomized, controlled study. SUBJECTS: A total of 3135 boys and girls in grades 1-4 were included in the study. METHODS: Ten schools were selected in Stockholm county area and randomized to intervention (n=5) and control (n=5) schools. Low-fat dairy products and whole-grain bread were promoted and all sweets and sweetened drinks were eliminated in intervention schools. Physical activity (PA) was aimed to increase by 30 min day(-1) during school time and sedentary behaviour restricted during after school care time. PA was measured by accelerometry. Eating habits at home were assessed by parental report. Eating disorders were evaluated by self-report. RESULTS: The prevalence of overweight and obesity decreased by 3.2% (from 20.3 to 17.1) in intervention schools compared with an increase of 2.8% (from 16.1 to 18.9) in control schools (P<0.05). The results showed no difference between intervention and controls, after cluster adjustment, in the longitudinal analysis of BMIsds changes. However, a larger proportion of the children who were initially overweight reached normal weight in the intervention group (14%) compared with the control group (7.5%), P=0.017. PA did not differ between intervention and control schools after cluster adjustment. Eating habits at home were found to be healthier among families with children in intervention schools at the end of the intervention. There was no difference between children in intervention and control schools in self-reported eating disorders. CONCLUSIONS: A school-based intervention can reduce the prevalence of overweight and obesity in 6 to 10-year-old children and may affect eating habits at home. The effect of the intervention was possibly due to its effect on healthy eating habits at school and at home rather than on increased levels of PA.


Assuntos
Promoção da Saúde/organização & administração , Obesidade/prevenção & controle , Aptidão Física , Antropometria , Criança , Análise por Conglomerados , Feminino , Humanos , Estudos Longitudinais , Masculino , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Sobrepeso/prevenção & controle , Pais/psicologia , Aptidão Física/psicologia , Prevalência , Comportamento de Redução do Risco , Serviços de Saúde Escolar , Suécia/epidemiologia
4.
Scand J Med Sci Sports ; 19(1): 30-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18248540

RESUMO

The aim of this study was to examine the stability of objectively measured physical activity in Swedish children and to study variables that predicted physical activity and body mass index standard deviation score (BMI SDS) at follow-up. A total of 97 children provided valid repeated measurements of physical activity between 2002 and 2005. The children were on average 7.5 years at baseline (SD+/-0.92) and 9 years at follow-up (SD+/-0.92). The mean follow-up time was approximately 1.5 years (mean 558 days, SD+/-224). An accelerometer (Actiwatch, Cambridge Neurotechnology Ltd., Cambridge, UK) was used to measure physical activity during 7 consecutive days. Yearly weight and height were examined and BMI SDS was calculated. Baseline physical activity was significantly correlated with physical activity at follow-up (r=0.59) with a stronger correlation for boys (r=0.72) than for girls (r=0.51). High physical activity levels were more stable (r=0.74) than low physical activity levels (r=0.55). Physical activity at follow-up was explained by physical activity at baseline and season (R(2)=0.46) whereas BMI SDS at follow-up was explained by BMI SDS at baseline and age (R(2)=0.90). The results of this study suggest that physical activity levels are fairly stable in 6-10-year-old children.


Assuntos
Aceleração , Exercício Físico , Monitorização Fisiológica/instrumentação , Antropometria , Índice de Massa Corporal , Criança , Feminino , Humanos , Modelos Lineares , Masculino , Suécia
5.
Am J Transplant ; 8(12): 2647-51, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18853956

RESUMO

Renal transplant patients have a high prevalence of osteopenia, osteoporosis and fractures. The aim of the study was to investigate whether dual-energy x-ray absorptiometry (DXA) is of value to predict fractures. In 1995-2007, 238 renal transplant patients underwent 670 DXA investigations. Osteopenia (46.0%), osteoporosis (13.9%) and absolute bone mineral density (BMD) (median 0.9, range 0.4-2.0 g/cm(2)) in the hip region were used to evaluate fracture risk. Data on fractures were collected at the occasion of each DXA, and a questionnaire was filled in by 191 patients at regular outpatient visits. Reported fractures were verified by consultation of medical records. In all, 46 patients had 53 fractures. Cumulative hazard of fracture was significantly different among normal BMD, osteopenia and osteoporosis in the hip (p < 0.0001). A Cox proportional hazard analysis also including age, gender and diabetic nephropathy showed significantly increased fracture risk for osteoporosis (3.5 times, CI 1.8-6.4, p = 0.0001) as well as for osteopenia (2.7 times, 1.6-4.6, p = 0.0003). A significantly increased risk was also found with absolute BMD estimates below the median. Osteopenia and an absolute bone density below 0.9 g/cm(2) in the hip region confer an increased risk of fracture.


Assuntos
Absorciometria de Fóton , Fraturas Ósseas/epidemiologia , Transplante de Rim , Complicações Pós-Operatórias , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Doenças Ósseas Metabólicas/complicações , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/fisiopatologia , Criança , Pré-Escolar , Feminino , Fraturas Ósseas/fisiopatologia , Humanos , Transplante de Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Osteoporose/diagnóstico , Osteoporose/fisiopatologia , Complicações Pós-Operatórias/fisiopatologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
6.
Scand J Rheumatol ; 37(1): 1-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18189187

RESUMO

OBJECTIVE: Atherosclerotic progression is accelerated in rheumatoid arthritis (RA). We evaluated arterial stiffness and endothelial dysfunction in RA patients and controls by pulse wave analysis (PWA). METHODS: Thirty RA patients with long-standing disease and 30 age- and sex-matched controls were examined using applanation tonometry of the radial artery before and after vasodilation by terbutaline (endothelium dependent) and nitroglycerin (endothelium independent). The aortic augmentation index (AIx) and time to reflected wave (transit time, Tr) were measured. Using the peripheral pulse curve, the stiffness index (SI) and the reflectance index (RI) were calculated. Tr and SI predominantly reflect large artery stiffness, whereas Aix and RI also reflect small vessel resistance. The PWA measurements were assessed in relation to adhesion molecules [soluble platelet endothelial cell adhesion molecule-1 (sPECAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1) and soluble intracellular adhesion molecule-1 (sICAM-1)], selectins (E, L and P), and inflammation [erythrocyte sedimentation rate (ESR), haptoglobin, interleukin (IL)-6, IL-1 receptor antagonist (IL-1-Ra), IL-2-soluble receptor (IL-2sR), and tumour necrosis factor receptors-I and -II (TNFR-I and TNFR-II)]. RESULTS: RA patients had shorter Tr (p<0.05) and higher SI (p<0.001) than controls, indicating impaired large vessel compliance. After terbutaline, Tr remained shorter (p<0.05), while SI (p<0.01) and AIx (p<0.01) were higher. The post-terbutaline changes in AIx and RI (DeltaAIx, DeltaRI), suggested to be the best PWA measurements of endothelial function, were smaller in RA patients (p = 0.06). In RA, L-selectin and sVCAM-1 correlated with DeltaRI and L-selectin also with DeltaAIx. Both RI and AIx correlated at baseline with a retrospective inflammatory activity score. CONCLUSION: Arterial stiffness was increased in RA patients. Endothelial dysfunction was implicated and correlated with levels of soluble adhesion molecules. Small vessel resistance correlated with the long-standing inflammatory load in RA.


Assuntos
Artrite Reumatoide/fisiopatologia , Endotélio Vascular/fisiopatologia , Pulso Arterial , Artéria Radial/fisiopatologia , Idade de Início , Artrite Reumatoide/tratamento farmacológico , Pressão Sanguínea/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Nitroglicerina/uso terapêutico , Artéria Radial/efeitos dos fármacos , Artéria Radial/fisiologia , Valores de Referência , Simpatomiméticos/uso terapêutico , Terbutalina/uso terapêutico , Vasodilatadores/uso terapêutico
7.
Am J Transplant ; 5(12): 2929-36, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16303007

RESUMO

Renal transplant recipients (RTR) have an increased risk of premature cardiovascular disease. The ALERT study is the first trial to evaluate the effect of statin therapy on cardiac outcomes following renal transplantation. Patients initially randomized to fluvastatin or placebo in the 5-6 year ALERT study were offered open-label fluvastatin XL 80 mg/day in a 2-year extension to the original study. The primary endpoint was time to first major adverse cardiac event (MACE). Of 1787 patients who completed ALERT, 1652 (92%) were followed in the extension. Mean total follow-up was 6.7 years. Mean LDL-cholesterol was 98 mg/dL (2.5 mmol/L) at last follow-up compared to a pre-study level of 159 mg/dL (4.1 mmol/L). Patients randomized to fluvastatin had a reduced risk of MACE (hazards ratio [HR] 0.79, 95% CI 0.63-0.99, p = 0.036), and a 29% reduction in cardiac death or definite non-fatal MI (HR 0.71, 95% CI 0.55-0.93, p = 0.014). Total mortality and graft loss did not differ significantly between groups. Fluvastatin produces a safe and effective reduction in LDL-cholesterol associated with reduced risk of MACE in RTR. The lipid-lowering and cardiovascular benefits of fluvastatin are comparable to those of statins in other patient groups, and support use of fluvastatin in RTR.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Ácidos Graxos Monoinsaturados/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Indóis/administração & dosagem , Transplante de Rim , Adulto , Doenças Cardiovasculares/mortalidade , Preparações de Ação Retardada , Ácidos Graxos Monoinsaturados/efeitos adversos , Feminino , Fluvastatina , Seguimentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Indóis/efeitos adversos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Fatores de Risco , Resultado do Tratamento
8.
Clin Nephrol ; 62(4): 279-86, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15524058

RESUMO

Studies of late renal allograft biopsies focus on chronic damage investigated by light microscopy (LM). We evaluated the use of immunohistochemistry (IH) as applied in the routine study of transplant glomerulopathies. Among renal transplants in 1985 - 1997, 129 were identified where a graft biopsy had been obtained 6 months or more after transplantation, studied by LM and IH and the original renal disease was known. IH results were evaluated in relation to glomerular LM findings and the original diagnosis. The risk of graft loss in relation to recurrent and de novo glomerulopathy was evaluated. By LM, 69 biopsies (53%) showed glomerulopathy, mesangial sclerosis only in 26, proliferative changes in 15, membranous in 15 and combined membranous and proliferative in 13. By IH, 46 biopsies (36%) stained positive with IgM and/or complement only and 24 with immune complexes including IgA and/or IgG. Seven biopsies (5.4%) showed glomerular disease by IH in spite of normal LM. Recurrence was diagnosed in 22 grafts; 12 had IgA nephropathy, 3 had SLE, 6 other immune complex nephritides and 1 systemic vasculitis. Twenty-eight biopsies (22%) with proliferative and/or membranous glomerulopathy lacked clear connection to the original renal disorder. More than half of these had deposits of IgM and C3 only. The further graft survival was significantly reduced in the presence of de novo glomerulopathy by LM, relative risk 2.0 (confidence interval 1.1 - 3.8) in a Cox-proportional hazards analysis also including serum creatinine and Banff chronic allograft nephropathy (CAN) grade, p = 0.03. In conclusion, transplant glomerulopathy should be separated from recurrence. De novo glomerulopathy is frequent and ominous.


Assuntos
Glomerulonefrite/etiologia , Glomerulonefrite/patologia , Imuno-Histoquímica , Glomérulos Renais/patologia , Transplante de Rim/efeitos adversos , Adolescente , Adulto , Biópsia por Agulha Fina , Criança , Feminino , Humanos , Imuno-Histoquímica/métodos , Masculino , Microscopia de Polarização , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Recidiva , Fatores de Tempo , Transplante Homólogo
9.
Br J Cancer ; 90(1): 48-54, 2004 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-14710205

RESUMO

The aim is to investigate the radiosensitivity of noninfected cultured human glioma cells to ascertain that intracutaneously administered cells are viable enough to produce interferon-gamma but not able to proliferate. Cell cultures were established from five patients undergoing brain tumour surgery. By karyotyping, we found four malignant (three glioblastoma multiforme (GBM), one giant cell glioma) and one normal. The cells were irradiated with (137)Cs-gamma rays at absorbed dose levels of 0, 20, 40, 60, 80, 100 and 120 Gy. The fraction of viable cells was examined by MTT incorporation assay. The average of the data obtained from three GBM cell cultures was fitted to an exponential model. The parameters were: extrapolation number n=0.85+/-0.10, mean lethal dose D(0)=12.4+/-3.2 Gy and an additional uncertainty parameter deltaS=0.14+/-0.03. By setting deltaS=0, the corresponding values of the parameters were n=0.86+/-0.16 and D(0)=30.0+/-8.1 Gy. The rate of proliferation was examined by (3)H-thymidine incorporation. The average of the proliferation data obtained from three GBM cell cultures was fitted to an exponential model yielding n=0.943+/-0.005 and D(0)=5.8+/-0.5 Gy for deltaS=0.057+/-0.005, and by setting deltaS=0, n=1.00+/-0.02 and D(0)=8.4+/-1.6 Gy. No outgrowth of plated cells was observed after 4 weeks at an absorbed dose of 100 Gy. This absorbed dose is recommended for irradiation of 2 x 10(6) glioma cells used for clinical immunisation.


Assuntos
Neoplasias Encefálicas/patologia , Sobrevivência Celular , Terapia Genética/métodos , Glioblastoma/patologia , Glioma/patologia , Imunoterapia , Interferon gama/biossíntese , Tolerância a Radiação , Divisão Celular , Radioisótopos de Césio/uso terapêutico , Humanos , Esterilização/métodos , Timidina/metabolismo , Trítio , Células Tumorais Cultivadas
10.
Acta Neurol Scand ; 109(2): 85-90, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14705968

RESUMO

OBJECTIVES: To evaluate the therapeutic efficiency and adverse effects of stereotactic proton beam treatment of cerebral arteriovenous malformations (AVM). MATERIAL AND METHODS: Twenty-six patients treated in Uppsala during 1991-97 were included (men = 14, women = 12; mean age = 39, range = 23-64). The nidus volumes ranged from 0.3 to 102 ml (mean = 24, median = 13). The follow-up included clinical evaluation, magnetic resonance imaging (and/or computed tomography) every 6-12 months for 3 years and final angiography. RESULTS: The volume changes at final follow-up in AVMs >25 ml were -89, -85, -44, -29, -7, 0, 0, +5 and +18 (%); in AVMs 11-24 ml, -100, -100, -97, -92 and 0 (%); and in AVMs <10 ml, -100, -100, -100, -100, -100, -99, -98, -50, -0 and +40 (%). Two patients were lost to follow-up due to cerebral haemorrhage and myocardial infarction. Radiology displayed significant perifocal oedema in one patient and slight oedema in four patients. Of nine patients with epilepsy, seven became seizure-free after therapy while two continued to suffer from seizures. CONCLUSION: Proton beam irradiation is successful in a relatively high proportion of intermediate and large-sized cerebral AVMs. The adverse effects are acceptable. The advantage of proton treatment compared with gamma knife and LINAC stereotactic irradiation is that protons can irradiate even large volumes with a very sharp dose profile against normal surroundings. Thus, proton beam irradiation is a valuable option in the treatment of AVMs larger than 10 ml.


Assuntos
Malformações Arteriovenosas Intracranianas/radioterapia , Adulto , Hemorragia Cerebral/etiologia , Fracionamento da Dose de Radiação , Edema/etiologia , Epilepsia/etiologia , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Terapia com Prótons , Técnicas Estereotáxicas , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
Br J Anaesth ; 88(4): 481-8, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12066722

RESUMO

BACKGROUND: The information contained in arterial pressure waveforms is probably underused by most clinicians who manage critically ill patients. It is not generally known that an aortic pressure wave can be synthesized by applying a generalized transfer function to the radial arterial pressure wave. We validated a commercially available system, SphygmoCo (PWV Medical, Sydney). METHODS: Ascending aortic pressure waves were synthesized and comparisons were made between the synthesized aortic waveforms, the measured aortic and radial arterial waveforms. Ascending aortic pressure waves (catheter-tip manometer) and radial artery pressure waves (short fluid-filled catheter) were recorded simultaneously in 12 patients with angina pectoris (age 62-76 years) undergoing cardiac catheterization. Patients were studied at rest, following midazolam, sublingual nitroglycerin and during Valsalva manoeuvres. RESULTS: Both midazolam and nitroglycerin lowered mean arterial pressure but nitroglycerin caused a more selective decrease in the measured and synthesized aortic systolic pressures than in the radial artery pressure. The synthesized aortic systolic pressure was less, by 6-8 mm Hg (SD 2-3) and the synthesized aortic diastolic pressure greater, by 4 mm Hg (SD 2). Despite these differences in pulse pressure, the synthesized waveform tracked the measured waveform before and during interventions. CONCLUSIONS: By deriving an aortic waveform from the radial pulse, monitoring of left ventricular afterload can improve without more invasive means.


Assuntos
Angina Pectoris/fisiopatologia , Aorta/fisiologia , Artéria Radial/fisiologia , Processamento de Sinais Assistido por Computador , Ansiolíticos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Cateterismo Cardíaco , Eletrocardiografia , Feminino , Humanos , Masculino , Midazolam/farmacologia , Monitorização Fisiológica/métodos , Nitroglicerina/farmacologia , Reprodutibilidade dos Testes , Manobra de Valsalva , Vasodilatadores/farmacologia
12.
Cancer ; 92(12): 3111-9, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11753990

RESUMO

BACKGROUND: Treatment of localized prostate carcinoma (LPC) using radiotherapy (RT) can induce disturbances in a patient's quality of life (QOL) and urinary and intestinal function. Late symptoms and QOL were evaluated in a randomized trial between RT and deferred treatment (DT). METHODS: Quality of life was evaluated with European Organization for Research and Treatment of Cancer's QLQ-C30 (+3) formula. Urinary and intestinal problems were evaluated with a validated symptom specific self-assessment questionnaire, QUFW94. The questionnaires were sent to 108 randomized patients with LPC and to an age-matched control group (n = 68). Mean age was 72 years. Mean total dose was 65 grays (Gy; 62.3-70 Gy). The median follow-up time from randomization was 40.6 months for the RT group and 30.4 months for the DT group. RESULTS: Social functioning was the only QOL scale in which a significant difference was found between the two patient groups and compared with the control group. Multivariate regression analysis showed that hematuria, incontinence, mucus, and planning of daily activities in response to intestinal problems caused this decrease in QOL in the RT group. A significant increase of intestinal problems was observed in the RT versus DT groups regarding mucus, stool leakage, intestinal blood, and planning of daily activity in response to intestinal problems. CONCLUSIONS: The RT patients showed increased levels of minor intestinal side effects compared with the DT patients and the controls, but the RT patients reported no decreased QOL except for decreased social functioning. This could be because this group developed coping skills or because of a low magnitude of side effects to influence the QOL.


Assuntos
Neoplasias da Próstata/radioterapia , Qualidade de Vida , Radioterapia/efeitos adversos , Comportamento Social , Adaptação Psicológica , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Gastroenteropatias/etiologia , Hematúria/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Regressão , Incontinência Urinária/etiologia
13.
Nephrol Dial Transplant ; 16(12): 2401-6, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11733633

RESUMO

BACKGROUND: Chronic allograft nephropathy (CAN) is a composite term for various types of damage to a kidney transplant. We wanted to analyse its components in relation to baseline biopsy findings, transplant function, and outcome. METHODS: Among renal transplantations performed from 1985 to 1997, 156 were identified where allograft biopsies had been obtained on clinical indication 6 months after transplantation or later, baseline biopsies were available in each case and the patient's original disease was known. Time after transplantation was median 2.2 years (range 0.5-13). The biopsies were reviewed and the Banff 1997 CAN score obtained. RESULTS: All but one late biopsy showed some CAN grade, 48% grade II, and 7.5% grade III. Acute tubulointerstitial rejection was seen in 9% but vascular rejection in only 3%. Arterial wall thickening was present in 66% of the late biopsies, correlated with donor age and its presence at baseline but also with time after transplantation. The Banff CAN score and serum creatinine level were both independent predictors of further graft survival, relative risk 0.35 (confidence interval 0.15-0.82, P=0.015) for CAN grade I vs III and 0.30 (0.14-0.67, P=0.003) for serum creatinine <170 vs >250 micromol/l. Presence of arterial wall thickening had no prognostic impact. CONCLUSION: The CAN grade is predictive of further graft survival independently of the serum creatinine level. Interstitial fibrosis and tubular atrophy are more prominent features of chronic graft damage than vascular rejection. Unspecific arterial wall thickening is partly dependent on baseline conditions and lacks prognostic impact in this late stage.


Assuntos
Nefropatias/etiologia , Nefropatias/patologia , Transplante de Rim/efeitos adversos , Rim/patologia , Doença Aguda , Adolescente , Adulto , Idoso , Biópsia , Criança , Creatinina/sangue , Feminino , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Tempo , Transplante Homólogo , Resultado do Tratamento
14.
Clin Transplant ; 15(4): 263-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11683821

RESUMO

Selection of patients for kidney transplantations is necessary due to the shortage of organs. The process has not been greatly studied. Twelve hypothetical cases were constructed, each with one or several relative contraindications, such as cardiovascular disease, diabetes, old age or a mental disorder. The cases were submitted to 40 nephrologists, chosen to represent the recruitment areas of the four Swedish transplant units. They were asked to declare whether the 'patient' was suitable for transplantation or not, and, independently, whether the patient would be referred to the transplant unit. The same cases were evaluated by 3-4 representatives of each transplant unit. The response rate was 100%. A median of 6 cases was considered suitable (range 3-11). The acceptance rate differed significantly between the four unit areas, from 4 cases (3-7) to 7 (4-11), p=0.014. Nephrologists would accept fewer patients than staff from the transplant units, 5 (3-10) vs. 7 (3-11), p=0.009. Most of the latter difference was compensated for by referral of borderline cases to the unit. Only 5 individual cases were equally judged by at least 75% of the respondents. Discrepancies in view were noted with respect to the significance of old or young age, the patient's determination and severe obesity.


Assuntos
Transplante de Rim , Seleção de Pacientes , Adulto , Atitude do Pessoal de Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nefrologia , Inquéritos e Questionários , Suécia , Uremia/fisiopatologia , Uremia/cirurgia
15.
Nature ; 411(6839): 789-92, 2001 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-11459055

RESUMO

The respiratory activities of plant roots, of their mycorrhizal fungi and of the free-living microbial heterotrophs (decomposers) in soils are significant components of the global carbon balance, but their relative contributions remain uncertain. To separate mycorrhizal root respiration from heterotrophic respiration in aboreal pine forest, we conducted a large-scale tree-girdling experiment, comprising 9 plots each containing about 120 trees. Tree-girdling involves stripping the stem bark to the depth of the current xylem at breast height terminating the supply of current photosynthates to roots and their mycorrhizal fungi without physically disturbing the delicate root-microbe-soil system. Here we report that girdling reduced soil respiration within 1-2 months by about 54% relative to respiration on ungirdled control plots, and that decreases of up to 37% were detected within 5 days. These values clearly show that the flux of current assimilates to roots is a key driver of soil respiration; they are conservative estimates of root respiration, however, because girdling increased the use of starch reserves in the roots. Our results indicate that models of soil respiration should incorporate measures of photosynthesis and of seasonal patterns of photosynthate allocation to roots.


Assuntos
Fungos/metabolismo , Fotossíntese , Raízes de Plantas/metabolismo , Microbiologia do Solo , Árvores/metabolismo , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Ecossistema , Raízes de Plantas/microbiologia , Estações do Ano , Árvores/microbiologia
16.
J Cardiovasc Risk ; 8(2): 63-71, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11324372

RESUMO

BACKGROUND: Recent clinical trials of primary and secondary prevention of cardiovascular disease have demonstrated that lowering plasma cholesterol with 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitors ('statins') reduces morbidity and mortality from coronary heart disease in diverse patient populations. STUDY AIMS: The aim of the present ALERT (Assessment of Lescol in Renal Transplantation) study is to determine whether renal transplant recipients would also benefit from statin therapy. ALERT is a multicentre, randomized, double-blind, placebo-controlled trial to assess the effect of fluvastatin in renal transplant recipients with mild-to-moderate hypercholesterolaemia. The primary objective is to investigate the effects of fluvastatin on major adverse cardiac events (MACE). In addition, the effects on cardiovascular and all-cause mortality, as well as renal function, will be addressed. STUDY POPULATION: The study population contains patients with functioning renal allografts of more than 6 months' duration, recruited from 75 centres in Northern Europe and Canada. Patients of both sexes, aged 30-75 years, with a total cholesterol level of 4.0-9.0 mmol/l (155-348 mg/dl) were included, except for those with a history of myocardial infarction, where the upper limit for inclusion was 7.0 mmol/l (270 mg/dl). STUDY DESIGN: A total of 2100 patients were recruited by the end of October 1997 and will be followed for up to 6 years. This report presents the design features of the study (recruitment, follow-up, sample size, data analysis and study organization), along with baseline results. ALERT is the first large-scale prospective, randomized, double-blind study to address the prevention of cardiovascular mortality in renal transplant patients receiving an HMGCoA reductase inhibitor.


Assuntos
Anticolesterolemiantes/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Ácidos Graxos Monoinsaturados/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Indóis/uso terapêutico , Transplante de Rim , Adulto , Idoso , Doenças Cardiovasculares/etiologia , Método Duplo-Cego , Feminino , Fluvastatina , Humanos , Hipercolesterolemia/complicações , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Projetos de Pesquisa , Fatores de Risco , Estatísticas não Paramétricas , Resultado do Tratamento
17.
Virchows Arch ; 438(2): 129-35, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11253114

RESUMO

Glomerular structural modifications were measured in kidney biopsies from two follow-up studies in type-1 diabetic patients with microalbuminuria and in kidney donors. Stereologic methods were used to obtain data on glomerular composition and absolute quantities per glomerulus to supplement data on diabetic glomerulopathy previously published. Diabetic patients at baseline (n=37) showed significant changes compared with controls (n=11). The volume fraction of tuft/glomerulus was increased, the proportion of capillary surface facing peripheral basement membrane was decreased (0.72+/-0.04 vs 0.77+/-0.03, P=0.0008), the ratio of mesangial surfaces, urinary/capillary, was decreased (0.67+/-0.17 vs 1.11+/-0.28, P<10(-4)), and the average capillary diameter was increased (8.9+/-0.9 microm vs 7.5+/-1.0 microm, P=0.0002). The total volume of mesangial extracellular material per glomerulus was increased (P=0.01), whereas glomerular volume was not significantly different from controls. Follow-up biopsies after antihypertensive treatment with ACE-inhibitor (n=7) or beta-blocker (n=6; 36-48 months) and after intensive insulin treatment (n=7; 24-33 months) showed no change. In a conventionally treated group (n=9), the glomerular volume, the volume of extracellular material/glomerulus, and the capillary length increased. The mean capillary diameter did not correlate with the glomerular volume. In conclusion, the development of diabetic glomerulopathy entails structural modifications of the glomerular tuft. Antihypertensive and intensified insulin treatment seem to slow the progression of ultrastructural changes.


Assuntos
Diabetes Mellitus Tipo 1/patologia , Nefropatias Diabéticas/patologia , Glomérulos Renais/ultraestrutura , Adulto , Albuminúria , Capilares/diagnóstico por imagem , Capilares/metabolismo , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Enalapril/uso terapêutico , Matriz Extracelular/metabolismo , Matriz Extracelular/ultraestrutura , Feminino , Humanos , Insulina/uso terapêutico , Sistemas de Infusão de Insulina , Glomérulos Renais/irrigação sanguínea , Glomérulos Renais/metabolismo , Masculino , Metoprolol/uso terapêutico , Microscopia Eletrônica , Resultado do Tratamento , Ultrassonografia
18.
Nucl Med Biol ; 28(1): 59-65, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11182565

RESUMO

76Br-bromodeoxyuridine has previously been suggested as a PET tracer to characterize proliferation potential. However, in animal studies a large fraction of the tissue radioactivity is due to 76Br-bromide, which remains extracellular for extensive periods and contributes significantly to the level of radioactivity. The present project aimed at investigating whether in human brain tumors, sufficient amounts of 76Br-bromodeoxyuridine would be incorporated into DNA, to motivate further attempts with this tracer. Eight patients with brain tumors: 3 meningiomas, 2 astrocytoma grade IV, 1 astrocytoma oligodendroglioma grade II-IV and 2 metastases, were examined with PET and 76Br-BrdU on three occasions: immediately after injection of the tracer, at 4-6, and at 18-20 hours after administration. After the first PET study, diuresis was introduced and maintained for about 12 hours. About 20 hours after tracer administration, 200 mg/m(2) bromodeoxyuridine was administered to 7 patients median 5.8 (range 1-22) hours prior to operation allowing the immunohistochemical analysis of the proliferation potential. During the operation, tumor samples were taken and radioactivity in DNA extracted and measured. The uptake of radioactivity was higher in the tumors than in brain parenchyma. However, in the operative samples only 1-27% (average: 9%) of the radioactivity was found in the DNA fraction. The plasma radioactivity remained high throughout the study with only minimal signs of elimination by the diuresis. 76Br-BrdU is extensively metabolized to 76Br-bromide, and only a minor fraction of the radioactivity is found in the DNA fraction, making it unlikely that this tracer can be used for assessment of proliferation potential.


Assuntos
Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Bromodesoxiuridina/farmacocinética , DNA de Neoplasias/metabolismo , Meningioma/metabolismo , Radiossensibilizantes/farmacocinética , Tomografia Computadorizada de Emissão , Idoso , Astrocitoma/química , Astrocitoma/diagnóstico por imagem , Neoplasias Encefálicas/química , Neoplasias Encefálicas/diagnóstico por imagem , Radioisótopos de Bromo , Bromodesoxiuridina/análise , Bromodesoxiuridina/sangue , DNA de Neoplasias/química , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Meningioma/química , Meningioma/diagnóstico por imagem , Pessoa de Meia-Idade , Radiossensibilizantes/análise
19.
Transplantation ; 71(1): 79-82, 2001 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11211199

RESUMO

BACKGROUND: The aim of this study was to establish the outcome of renal transplantation in patients given pretransplant erythropoietin (EPO) treatment targeted at reaching a normal hemoglobin concentration (Hb), compared to those given EPO-treatment aimed at maintaining subnormal Hb. METHODS: A total of 416 patients from Scandinavian countries and with renal anaemia were enrolled to examine the effects of increasing Hb from a subnormal level (90-120 g/liter) to a normal level (135-160 g/liter) by EPO treatment. Half of the patients were randomized to have their Hb increased, with the other half randomized to maintain a subnormal Hb. Thirty-two patients from the normal Hb group and 24 patients from the subnormal group received a renal graft during the study period. The outcomes of these transplantations were examined prospectively for 6 months. RESULTS: Preoperative Hb levels were 143+/-17 and 121+/-14 g/liter in the two groups, respectively (P<0.0001). The Hb remained higher in the normal Hb group during the first 2 weeks after transplantation. The percentage of patients requiring postoperative blood transfusions in the normal Hb group was 16%, compared with 50% in the subnormal group (P<0.01). No statistically significant difference in the proportion of functioning grafts or in the serum creatinine levels could be detected. No correlation between EPO treatment and creatinine levels after transplantation was found. The frequency of adverse events was similar in the two groups. CONCLUSIONS: EPO treatment aimed at reaching a normal Hb in renal transplant recipients reduces the postoperative requirement for blood transfusions and has no deleterious effects on kidney graft function.


Assuntos
Eritropoetina/farmacologia , Hemoglobinas/metabolismo , Transplante de Rim/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
20.
Nephrol Dial Transplant ; 16(2): 383-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11158417

RESUMO

BACKGROUND: The anterior extraperitoneal approach for living donor nephrectomy has been used in more than 700 living cases in the unit and proved to be safe for the donor. In 1998, laparoscopic nephrectomy was introduced as an option when technically feasible. We found it essential to investigate the consequences of the new technique. SUBJECTS AND METHODS: One hundred living donor kidney transplantations were performed from 1998 to June 2000, 45 with laparoscopic, 55 with open nephrectomy. The donors took part in a structured interview 4 weeks after the donation and their responses were categorized in three classes. RESULTS: In each group, one recipient had delayed initial function. The serum creatinine levels after 3 and 7 days or the GFR values after 6 months did not differ. One graft has been lost following laparoscopic nephrectomy and four after open surgery. For the laparoscopy donors, the median number of post-operative days in hospital was 5.0 days (range 2-9), vs 6.0 (4-8) after open surgery (NS). The requirement of opoid analgesics post-operatively was 5.0 doses (1-22) vs 6.0 (1-38) (P=0.02); and after 4 weeks, 23 of 45 laparoscopic donors were free of pain vs eight of 55 open nephrectomy donors (P=0.0004). Approximately one-third of all donors felt some restriction of physical activity and the majority complained of impaired physical energy. There were no differences between the groups. The duration of sick-leave after laparoscopic surgery was median 6 (2-19) weeks vs 7 (1-16) (NS). CONCLUSIONS: Laparoscopic nephrectomy is safe. Less post-operative pain is a definite advantage for the donor.


Assuntos
Laparoscopia , Doadores Vivos , Nefrectomia/métodos , Adulto , Idoso , Feminino , Humanos , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Nefrectomia/efeitos adversos , Dor Pós-Operatória/fisiopatologia , Circulação Renal , Infecção da Ferida Cirúrgica , Doenças Ureterais/etiologia , Doenças Vasculares/etiologia
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