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1.
BMC Nephrol ; 22(1): 283, 2021 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-34419006

RESUMEN

BACKGROUND: An arteriovenous fistula (AVF) is the preferred vascular access for hemodialysis treatment. After creation many of the AVFs will never mature or if functioning will need an intervention within 1 year due to an AVF stenosis. Studies investigating possible therapies that improves the AVF maturation and survival are scarce. Far infrared therapy (FIR) has shown promising results. In minor single centre and industry supported trials FIR has shown improved AVF maturation and survival. There is a need of a randomized multicentre controlled trial to examine the effect of FIR on the AVF maturation and survival and to explore the possible AVF protective mechanism induced by the FIR treatment. METHODS: This investigator initiated, randomized, controlled, open-labeled, multicenter clinical trial will examine the effect of FIR on AVF maturation in patients with a newly created AVF (incident) and AVF patency rate after 1 year of treatment in patients with an existing AVF (prevalent) compared to a control group. The intervention group will receive FIR to the skin above their AVF three times a week for 1 year. The control group will be observed without any treatment. The primary outcome for incident AVFs is the time from surgically creation of the AVF to successful cannulation. The primary outcome for the prevalent AVFs is the difference in number of AVFs without intervention and still functioning in the treatment and control group after 12 months. Furthermore, the acute changes in inflammatory and vasodilating factors during FIR will be explored. Arterial stiffness as a marker of long term AVF patency will also be examined. DISCUSSION: FIR is a promising new treatment modality that may potentially lead to improved AVF maturation and survival. This randomized controlled open-labelled trial will investigate the effect of FIR and its possible mechanisms. TRIAL REGISTRATION: Clinicaltrialsgov NCT04011072 (7th of July 2019).


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Cateterismo/métodos , Rayos Infrarrojos , Fallo Renal Crónico/terapia , Diálisis Renal , Adulto , Constricción Patológica/radioterapia , Humanos , Grado de Desobstrucción Vascular
2.
Oncogene ; 36(7): 933-941, 2017 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-27477692

RESUMEN

Tumor surveillance of natural killer (NK) cells is mediated by the cytotoxicity receptor natural-killer group 2 member D (NKG2D). Ligands for NKG2D are generally not expressed on healthy cells, but induced on the surface of malignant cells. To date, NKG2D ligand (NKG2D-L) induction was mainly described to depend on the activation of the DNA damage response, although the molecular mechanisms that regulate NKG2D-L expression remain largely unknown. Here, we show that the acetyltransferases CBP (CREB-binding protein) and p300 play a crucial role in the regulation of NKG2D-L on tumor cells. Loss of CBP/p300 decreased the basal cell surface expression of human ligands and reduced the upregulation of MICA/B and ULBP2 in response to histone deacetylase inhibitors or DNA damage. Furthermore, CBP/P300 deficiency abrogated the sensitivity of stressed cells to NK cell-mediated killing. CBP/p300 were also identified as major regulators of mouse NKG2D ligand RAE-1 in vitro and in vivo using the Eµ-Myc lymphoma model. Mechanistically, we observed an enhanced activation of the CBP/p300 binding transcription factor CREB (cAMP response element-binding protein) correlating to the NKG2D-L upregulation. Moreover, increased binding of CREB and CBP/p300 to NKG2D-L promoters and elevated histone acetylation were detectable. This study provides strong evidence for a major role of CBP and p300 in orchestrating NKG2D-L induction and consequently immunosurveillance of tumors in mice and humans. These findings might help to develop novel immunotherapeutic approaches against cancer.


Asunto(s)
Antígenos de Histocompatibilidad Clase I/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Linfoma/metabolismo , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Proteínas Asociadas a Matriz Nuclear/genética , Proteínas de Transporte Nucleocitoplasmático/genética , Factores de Transcripción p300-CBP/metabolismo , Acetilación , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Proteínas Ligadas a GPI/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Linfoma/genética , Linfoma/patología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Subfamilia K de Receptores Similares a Lectina de Células NK/genética , Transcripción Genética , Factores de Transcripción p300-CBP/genética
3.
Blood Cancer J ; 3: e106, 2013 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-23524591

RESUMEN

Tumors develop when infiltrating immune cells contribute growth stimuli, and cancer cells are selected to survive within such a cytotoxic microenvironment. One possible immune-escape mechanism is the upregulation of PI-9 (Serpin B9) within cancer cells. This serine proteinase inhibitor selectively inactivates apoptosis-inducing granzyme B (GrB) from cytotoxic granules of innate immune cells. We demonstrate that most classical Hodgkin lymphoma (cHL)-derived cell lines express PI-9, which protects them against the GrB attack and thereby renders them resistant against GrB-based immunotherapeutics. To circumvent this disadvantage, we developed PI-9-insensitive human GrB mutants as fusion proteins to target the Hodgkin-selective receptor CD30. In contrast to the wild-type GrB, a R201K point-mutated GrB construct most efficiently killed PI-9-positive and -negative cHL cells. This was tested in vitro and also in vivo whereby a novel optical imaging-based tumor model with HL cell line L428 was applied. Therefore, this variant, as part of the next generation immunotherapeutics, also named cytolytic fusion proteins showing reduced immunogenicity, is a promising molecule for (targeted) therapy of patients with relapsing malignancies, such as cHL, and possibly other PI-9-positive malignancies, such as breast or lung carcinoma.

4.
Diabet Med ; 30(5): 563-6, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23324103

RESUMEN

AIMS: Hydrogen sulphide levels are reduced in many disease states, including diabetes and end-stage renal disease. We aimed to determine whether urinary sulphate excretion, as a proxy for hydrogen sulphide, was associated with progression of diabetic nephropathy. METHODS: We conducted a post-hoc study of a prospective, randomized, controlled trial on the effect of a low vs. normal protein diet for 4 years, on decline of renal function in patients with Type 1 diabetes and diabetic nephropathy. We excluded patients with less than three measurements of glomerular filtration rate assessed by (51)Cr-EDTA plasma clearance (GFR) and less than 1 year of follow-up (n = 10), leaving 72 patients eligible for analyses. We studied both association of rate of decline in GFR and association of the combined endpoint of end-stage renal disease and death with baseline 24-h urinary sulphate excretion. RESULTS: Sulphate excretion was significantly associated with the slope of GFR (rs = -0.28, P = 0.02). In a multivariate regression model, sulphate excretion was a significant determinant of decline in GFR, independent of age, gender, blood pressure, HbA1c , smoking, albuminuria, baseline GFR and diet group (P < 0.01). In addition, adjusted r(2) increased from 5% in a model with the aforementioned risk factors to 22% when sulphate excretion was included in the model. Cox regression revealed a hazard ratio of 0.34 (95% CI 0.13-0.88, P = 0.026) for each natural log unit increase in urinary sulphate excretion. CONCLUSION: High urinary sulphate excretion was significantly associated with slower decline in (51)Cr-EDTA-assessed GFR in diabetic nephropathy, independent of known progression promoters.


Asunto(s)
Albuminuria/orina , Diabetes Mellitus Tipo 1/orina , Nefropatías Diabéticas/orina , Fallo Renal Crónico/orina , Sulfitos/orina , Adulto , Biomarcadores/orina , Diabetes Mellitus Tipo 1/fisiopatología , Nefropatías Diabéticas/fisiopatología , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Tasa de Filtración Glomerular , Humanos , Fallo Renal Crónico/fisiopatología , Masculino , Estudios Prospectivos , Factores de Riesgo
5.
Sci Total Environ ; 433: 482-90, 2012 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22820617

RESUMEN

The Water Framework Directive (WFD) is an ambitious piece of legislation focused on achieving good ecological status as defined by deviations from reference conditions. Achieving good ecological status depends on collaboration between stakeholders, scientists and the public. However, public participation is restricted to consultations about implementing measures to achieve good ecological status, not in the goal setting. There are multiple, competing interpretations of good ecological status. This study addresses two of the pillars of the WFD, good ecological status and public participation. We argue that these two pillars are currently at odds when defining reference conditions for surface waters, and it is unclear how they can work together in practice. We also contend that there is an intention in the WFD to integrate these two pillars, but there is no legal support for their connection. In a case study of a small boreal lake in Sweden, we show that local people possess a great deal of historical knowledge, which they use to conceptualize reference conditions. Their conceptualizations are compared with fish and water chemistry monitoring by the regulatory authority as well as paleolimnological reconstructions of water quality dating back to the beginning of the 20th century. The knowledge that the local people have corresponds to the historical data available for the lake, particularly with water clarity. We highlight the subjective nature of the concept of 'undisturbed state' to show that it varies depending on values, knowledge and perceptions of lay-people, scientists and relevant authorities. The subjectivity of the concept of undisturbed state promises to be a way of linking the two pillars of the WFD.

6.
Leukemia ; 24(1): 51-7, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19890373

RESUMEN

Combinations with proteasome inhibitors are currently being investigated to improve the therapy of hematological malignancies. We previously found that proteasome inhibition by bortezomib failed to sensitize anti-CD30 antibody (Ab)-based lymphoma cell killing. In this study, we demonstrate in L540 Hodgkin's lymphoma cells that proteasome inhibition not only communicates apoptosis but also more rapidly causes a loss of CD30 antigen from cell membrane and a simultaneous release of soluble CD30, a targeting competitor. This shedding was catalyzed by the tumor necrosis factor (TNF)-alpha-converting enzyme (TACE, ADAM17) and blocked by the ADAM17-selective inhibitor, Ro32-7315. In parallel with CD30 shedding, bortezomib caused the generation of reactive oxygen species (ROS). As apoptosis and shedding were inhibited by the radical scavenger, N-acetyl-L-cysteine, ROS might have a pivotal function in both effects. In contrast, the pan-caspase inhibitor, zVAD-fmk, blocked bortezomib-induced apoptosis but not CD30 shedding, and Ro32-7315 blocked shedding but allowed apoptosis. This suggests independent terminal signaling pathways that are conflicting in Ab-based immunotherapy. Consequently, shedding inhibition substantially improved the synergistic antitumor efficacy of the human anti-CD30 Ab, MDX-060, and bortezomib. As proteasome inhibition also stimulated loss of TNF receptors, interleukin-6 receptor and syndecan-1 in different leukemia and lymphoma cell lines, we concluded that proteasome inhibition might impede targeted therapy against antigens susceptible to shedding.


Asunto(s)
Proteínas ADAM/fisiología , Ácidos Borónicos/farmacología , Antígeno Ki-1/análisis , Inhibidores de Proteasoma , Pirazinas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Proteína ADAM17 , Acetilcisteína/farmacología , Anticuerpos Monoclonales/farmacología , Bortezomib , Línea Celular Tumoral , Humanos , Ácidos Hidroxámicos/farmacología , Sulfonamidas/farmacología , Sindecano-1/análisis
7.
Diabetologia ; 51(6): 956-61, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18385971

RESUMEN

AIMS/HYPOTHESIS: In type 1 diabetic patients with microalbuminuria not receiving antihypertensive treatment, an increase in urinary AER (UAER) of 6-14%/year and a risk of developing diabetic nephropathy (DN) of 3-30%/year have been reported. We audited the long-term effect of blocking the renin-angiotensin-aldosterone system (RAAS) with an ACE inhibitor (ACEI) or angiotensin II receptor blocker (ARB) in microalbuminuric type 1 diabetic patients on progression of microalbuminuria and development of DN. METHODS: All patients with type 1 diabetes and persistent microalbuminuria (30-300 mg/24 h) were identified (n=227) in 1995 at Steno Diabetes Center and followed for 11 years. Development of DN was defined as a UAER of >300 mg/24 h in two of three consecutive urine samples. RESULTS: Age and duration of diabetes at baseline (mean+/-SD) were 46+/-15 and 28+/-13 years, respectively. During follow-up 14 patients emigrated and 58 (26%) died. Over the same period 79% were treated with an ACEI or ARB. There was a mean decline in UAER of 4%/year. Sixty-five patients (29%) progressed to overt DN, corresponding to 3.1%/year. However, 29 of them regressed to normo- or microalbuminuria on intensified antihypertensive treatment. Glycaemic control and blood pressure remained nearly unchanged. CONCLUSIONS/INTERPRETATION: In our outpatient clinic, the implementation of RAAS-blocking treatment in type 1 diabetic patients with microalbuminuria successfully reduced long-term progression to overt DN to a rate similar to those previously reported in randomised, double-blind intervention trials of shorter duration using RAAS blockade.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Diabetes Mellitus Tipo 1/complicaciones , Nefropatías Diabéticas/prevención & control , Auditoría Médica , Adulto , Albuminuria/epidemiología , Albuminuria/mortalidad , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Presión Sanguínea , Progresión de la Enfermedad , Tasa de Filtración Glomerular , Hemoglobina Glucada/análisis , Humanos , Fallo Renal Crónico/prevención & control , Persona de Mediana Edad , Accidente Cerebrovascular/mortalidad , Análisis de Supervivencia
8.
Scand J Clin Lab Invest ; 61(6): 471-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11681537

RESUMEN

In type 1 diabetic patients with microalbuminuria not receiving antihypertensive treatment, an increase in urinary albumin excretion rate (AER) of 6% to 14%/year and a risk for the development of diabetic nephropathy of 3% to 30%/year have previously been reported. The aim of the present study was to audit the effect of angiotensin converting enzyme (ACE) inhibition on the progression of microalbuminuria and development of diabetic nephropathy. We consecutively identified 227 type 1 diabetic patients with persistent microalbuminuria (urinary AER between 30 and 300mg/24h, ELISA). According to the level (> or = 100 or < 100mg/24 h) and/or rate of progression in urinary AER (>6% or < or =6%/year), patients were divided into a high-risk group (n= 177) and a low-risk group (n= 50) for development of diabetic nephropathy. According to international guidelines, all patients at high-risk were recommended ACE-inhibitor treatment. Throughout the study, 67% of the patients were treated with an ACE inhibitor. Urinary AER significantly declined by 8.3%/year (95% CI: 2.8 to 13.9) in the whole group of patients, and the risk for the development of diabetic nephropathy during follow-up was 3.5%/year. Glycaemic control and blood pressure remained unchanged during the study. The implementation of modified international guidelines regarding the use of ACE inhibition in the treatment of microalbuminuric type 1 diabetic patients reduced progression to diabetic nephropathy comparable to what has previously been reported in intervention trials.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Diabetes Mellitus Tipo 1/complicaciones , Nefropatías Diabéticas/prevención & control , Auditoría Médica , Albuminuria/complicaciones , Glucemia/análisis , Presión Sanguínea , Nefropatías Diabéticas/complicaciones , Nefropatías Diabéticas/orina , Ensayo de Inmunoadsorción Enzimática , Humanos
9.
Kidney Int ; 60(1): 228-34, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11422755

RESUMEN

BACKGROUND: The purpose of this study was to assess whether long-term (8 years) inhibition of angiotensin-converting enzyme (ACE) protects kidney function in normotensive type 1 diabetic patients with diabetic nephropathy. METHODS: We performed an open randomized follow-up study of normotensive type 1 diabetics with nephropathy either treated (N = 15) or not (N = 17) with captopril twice per day (average 74, range 12.5 to 125 mg/day). The main outcome measures were arterial blood pressure, albuminuria, and glomerular filtration rate (GFR; 51Cr-EDTA plasma clearance, twice yearly). RESULTS: Arterial blood pressure (mm Hg) was kept constant in the captopril group, at baseline (mean, SEM), 128/78 (3/2) and during follow-up 129/77 (4/1) but increased significantly in the control group from 127/79 (2/1) to 137/84 (5/2) (P < 0.01). Furthermore, 8 out of the 17 control subjects required treatment with blood pressure-lowering drugs because they developed hypertension. The fractional albumin clearance (x10-5) remained unchanged in the captopril group: baseline [10.8 (1.25) geometric mean and antilog (SEM)] during the eight years [11.8 (1.47)], while a significant rise occurred in control patients: 13.3 (1.23) to 26.2 (1.42) (P < 0.05). Baseline GFR was nearly identical: 111 (6) and 115 (4) mL/min/1.73 m2 in the captopril and control group, respectively. The median (range) rate of decline in GFR (mL/min/year) was 1.7 (10.7 to -2.0) in the captopril group versus 2.8 (17.7 to -2.6) in the control group (P = NS). CONCLUSIONS: The beneficial effect of captopril in arresting the rise in systemic blood pressure and albuminuria is long lasting. A loss in GFR is minimal in most patients with diabetic nephropathy if normotension is sustained by prospective treatment with ACE inhibitors or restored by implementation of other antihypertensive medications with the development of hypertension.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Captopril/uso terapéutico , Diabetes Mellitus Tipo 1/fisiopatología , Nefropatías Diabéticas/tratamiento farmacológico , Adulto , Albuminuria/orina , Nefropatías Diabéticas/fisiopatología , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Humanos , Masculino , Estudios Prospectivos , Valores de Referencia , Factores de Tiempo
10.
Diabetes Care ; 23(12): 1742-5, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11128344

RESUMEN

OBJECTIVE: High-dose treatment with cyclooxygenase inhibitors reduces urinary albumin excretion rate (AER) in type 1 diabetic patients with microalbuminuria and macroalbuminuria. This effect may lead to an incorrect classification of albuminuria (normo-, micro-, and macroalbuminuria) and jeopardize the monitoring of antiproteinuric treatment (e.g., ACE inhibition). Whether similar difficulties exist using low-dose acetylsalicylic acid (ASA), now widely recommended for primary and secondary prevention of cardiovascular events in type 1 diabetic patients with micro- and macroalbuminuria, remains to be elucidated. RESEARCH DESIGN AND METHODS: We performed a randomized double-blind crossover trial in 17 type 1 diabetic patients with microalbuminuria (urinary AER 30-300 mg/24 h). Patients were given ASA (150 mg/daily) for 4 weeks followed by placebo for 4 weeks with at least a 2-week washout period in random order. At the end of each treatment period, AER (enzyme-linked immunosorbent assay), glomerular filtration rate (GFR) (plasma clearance of 51Cr-EDTA), blood pressure (BP) (Hawksley), and HbA1c (by high-performance liquid chromatography) were measured. Patients were advised to follow a normal diabetes diet without sodium restriction and received their usual antihypertensive treatment during the investigation. RESULTS: During the study (ASA vs. placebo), urinary AER (geometric mean 64 [95% CI 39-105] vs. 59 [40-87] mg/24 h), GFR (mean 106 [93-118] vs. 104 [90-117] ml x min(-1) x 1.73 m(-2)), systolic BP (mean 130 [119-141] vs. 130 [119-142] mmHg), diastolic BP (mean 71 [65-78] vs. 71 [64-78] mmHg), and HbA1c (mean 8.4% [8.0-9.0] vs. 8.5% [8.1-9.0]) remained unchanged. CONCLUSIONS: Treatment with 150 mg ASA daily does not have any impact on AER or GFR in type 1 diabetic patients with microalbuminuria. Consequently, primary and secondary prevention of cardiovascular events with low-dose ASA does not interfere with the classification of AER or monitoring of antiproteinuric treatment in such patients.


Asunto(s)
Albuminuria/tratamiento farmacológico , Aspirina/administración & dosificación , Diabetes Mellitus Tipo 1/fisiopatología , Riñón/fisiopatología , Adulto , Aspirina/efectos adversos , Aspirina/uso terapéutico , Presión Sanguínea , Cromatografía Líquida de Alta Presión , Estudios Cruzados , Diabetes Mellitus Tipo 1/orina , Método Doble Ciego , Ensayo de Inmunoadsorción Enzimática , Femenino , Tasa de Filtración Glomerular , Hemoglobina Glucada/análisis , Humanos , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Placebos
11.
J Immunol ; 165(12): 6703-9, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11120787

RESUMEN

CD30 is a costimulatory receptor on activated lymphocytes and a number of human lymphoma cells. Specific ligation of membrane-bound CD30 or cellular stimulation by PMA results in a metalloproteinase-mediated down-regulation of CD30 and release of its soluble ectodomain (sCD30). In this report, it is demonstrated that PMA-induced CD30 cleavage from Karpas 299 cells was mediated by a membrane-anchored metalloproteinase which was active on intact cells following 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate extraction of membrane preparations. Moreover, CD30 shedding was blocked by the synthetic hydroxamic acid-based metalloproteinase inhibitor BB-2116 (IC(50), 230 nM) and the natural tissue inhibitor of metalloproteinases (TIMP)-3 (IC(50), 30 nM), but not by the matrix metalloproteinase inhibitors TIMP-1 and TIMP-2. This inhibition profile is similar to that of the TNF-alpha- converting enzyme (TACE) and, indeed, mRNA transcripts of the membrane-bound metalloproteinase-disintegrin TACE could be detected in Karpas 299 cells. The ectodomain of TACE was expressed in bacteria as a GST fusion protein (GST-TACE) which cleaved CD30 from the surface of Karpas 299 cells and concomitantly increased the level of sCD30 in the cell supernatants. Hence, TACE does not only control the release of TNF-alpha, but also that of sCD30.


Asunto(s)
Antígeno Ki-1/metabolismo , Linfoma/enzimología , Linfoma/inmunología , Metaloendopeptidasas/fisiología , Factor de Necrosis Tumoral alfa/fisiología , Proteínas ADAM , Proteína ADAM17 , Membrana Celular/enzimología , Membrana Celular/inmunología , Membrana Celular/metabolismo , Células Cultivadas , Humanos , Hidrólisis , Ácidos Hidroxámicos/farmacología , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Linfocitos/metabolismo , Linfoma/genética , Linfoma/metabolismo , Metaloendopeptidasas/antagonistas & inhibidores , Metaloendopeptidasas/genética , ARN Mensajero/análisis , Proteínas Recombinantes/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Inhibidor Tisular de Metaloproteinasa-3/farmacología , Células Tumorales Cultivadas/inmunología , Células Tumorales Cultivadas/metabolismo
12.
Diabet Med ; 16(7): 555-62, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10445830

RESUMEN

AIMS: To elucidate the putative factors involved in the blunted nocturnal blood pressure reduction in hypertensive Type 2 diabetic patients with diabetic nephropathy. METHODS: Extracellular fluid volume and fluid shift from interstitial to plasma volume (haematocrit), sympathetic nervous activity (plasma noradrenaline and adrenaline) and the internal 'body clock' (serum melatonin) were investigated in 31 hypertensive Type 2 diabetes mellitus (DM) patients with diabetic nephropathy (24 males, age 60 (45-73) years). All variables, except extracellular volume, were measured repeatedly with the patients lying awake in bed from 21:30 to 23:00 h (baseline) and during sleep from 23:00 to 07:00 h. Using the median nocturnal blood pressure reduction (8.4%) as a guide, the patients were divided into groups; group 1 with the highest and group 2 with the lowest nocturnal blood pressure reduction. RESULTS: Haematocrit decreased from baseline to the sleep period in group 1 by a mean (95% confidence interval (CI)) of 1.7 (0.3-3.1)%, but it increased by 0.5 (-1.0-1.9)% in group 2, mean difference (95% CI), -2.1 (-4.0 to -0.2)% (P = 0.029). Noradrenaline decreased from baseline to the sleep period, mean (95% CI), by 13.3 (0.0-25.0)% in group 1 but rose by 7.7 (-9.7-28.4)% in group 2, mean difference (95% CI), -19.6 (-35-0.0)% (P = 0.049). The nocturnal blood pressure change correlated to the nocturnal change in both noradrenaline (r = 0.51, P = 0.004) and haematocrit (r = 0.42, P = 0.018). Adrenaline remained constant in both groups. Extracellular fluid volume and plasma melatonin levels were comparable in the two groups. CONCLUSION: Sustained adrenergic activity during sleep is associated with blunted nocturnal blood pressure reduction in hypertensive Type 2DM patients with diabetic nephropathy, probably mediated through a lack of peripheral vasodilatation whereas changes in extracellular fluid volume distribution and melatonin secretion have no impact.


Asunto(s)
Presión Sanguínea , Diabetes Mellitus Tipo 2/fisiopatología , Angiopatías Diabéticas/fisiopatología , Nefropatías Diabéticas/fisiopatología , Neuropatías Diabéticas/fisiopatología , Hipertensión/fisiopatología , Sueño/fisiología , Sistema Nervioso Simpático/fisiopatología , Anciano , Ritmo Circadiano , Diabetes Mellitus Tipo 2/sangre , Nefropatías Diabéticas/sangre , Diástole , Epinefrina/sangre , Femenino , Tasa de Filtración Glomerular , Frecuencia Cardíaca , Hematócrito , Humanos , Masculino , Persona de Mediana Edad , Norepinefrina/sangre , Volumen Plasmático , Análisis de Regresión , Sístole , Vigilia
14.
Kidney Int ; 55(2): 621-8, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9987086

RESUMEN

BACKGROUND: Initiation of a low-protein diet (LPD) in patients with various nephropathies induces a faster initial and slower subsequent decline in the glomerular filtration rate (GFR). Whether this initial phenomenon is reversible or irreversible remains to be elucidated. METHODS: We performed an eight-week prospective, randomized, controlled study comparing the effect of an LPD with a normal-protein diet (NPD) in 29 insulin-dependent diabetic patients with diabetic nephropathy. At baseline, the patients were randomized to either an LPD (0.6 g.kg-1.24 hr-1, LPD group, N = 14) or their NPD (NPD group, N = 15) for four weeks (phase I). Between weeks 4 and 8, all patients received their NPD (phase II, recovery). Dietary protein intake (g.kg-1.24 hr-1), GFR (51Cr-EDTA, ml.min-1.1.73 m-2), albuminuria (enzyme-linked immunoadsorbent assay, mg.24 hr-1), and arterial blood pressure (Hawksley random zero sphygmomanometer, mm Hg) were measured at baseline and after four- and eight-weeks of follow-up. During the investigation, all patients in the LPD group (N = 12) and in the NPD group (N = 14) received their usual antihypertensive treatment. RESULTS: At baseline, the LPD group and the NPD group were comparable regarding dietary protein intake, GFR, albuminuria, and arterial blood pressure. During phase I, a significant decline in dietary protein intake, GFR, and albuminuria (mean, 95% CI) was observed in the LPD group [0.4 (0.3 to 0.5) g.kg-1.24 hr-1, 8.6 (3.2 to 13.9) ml.min-1.1.73 m-2, and 28.7 (14.0 to 40.9)%, respectively] compared with the NPD group [0.0 (-0.1 to 0.2) g.kg-1.24 hr-1 (P < 0.0001 between diets), 2.5 (-1.8 to 6.8) ml.min-1.1.73 m-2 (P = 0.07 between diets), and 0.0 (-20.1 to 23.5)% (P < 0.05 between diets), respectively]. Conversely, during phase II, a significant increase in dietary protein intake, GFR, and albuminuria [mean, 95% CI; 0.3 (0.2 to 0.5) g.kg-1.24 hr-1, 5.9 (0.8 to 11.1) ml.min-1.1.73 m-2, and 25.0 (4.5 to 49.6)%, respectively] took place in the LPD group compared with the NPD group [0.0 (-0.2 to 0.1) g.kg-1.24 hr-1 (P < 0.0001 between diets), -2.9 (-6.4 to 0.6) ml.min-1.1.73 m-2 (P < 0.01 between diets), and 2.9 (-18.3 to 29.7)% (P = 0.16 between diets), respectively]. Arterial blood pressure was comparable in the two groups of patients during phase I and II. CONCLUSIONS: Dietary protein restriction for four weeks induces a reversible decline in GFR and albuminuria in insulin-dependent diabetic patients with diabetic nephropathy, whereas systemic blood pressure remains unchanged.


Asunto(s)
Diabetes Mellitus Tipo 1/fisiopatología , Nefropatías Diabéticas/dietoterapia , Nefropatías Diabéticas/fisiopatología , Proteínas en la Dieta/administración & dosificación , Riñón/fisiopatología , Adulto , Albuminuria/orina , Presión Sanguínea/efectos de los fármacos , Nefropatías Diabéticas/tratamiento farmacológico , Proteínas en la Dieta/farmacología , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/uso terapéutico , Insulina/administración & dosificación , Insulina/uso terapéutico , Masculino , Persona de Mediana Edad , Natriuresis/efectos de los fármacos , Natriuresis/fisiología , Estudios Prospectivos
15.
Scand J Clin Lab Invest ; 58(5): 405-13, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9819189

RESUMEN

Plasma clearance of 51Cr-EDTA is widely used to assess the glomerular filtration rate (GFR) in diabetic nephropathy. Originally, the ratio between the intravenously injected amount of tracer and the total area under the plasma concentration curve was used for the calculation of total 51Cr-EDTA plasma clearance (C(T)). Simplified methods, using the final mono-exponential part of the plasma curve, have been suggested, e.g. four samples, taken 180 to 240 min after injection (C(IV)), or using one sample taken at 240 min (C(I)). Our aim was to evaluate the agreement between measurements of GFR and rate of decline in GFR based upon these three methods. Bland & Altman plots were used to illustrate the range of agreement. We investigated 76 insulin-dependent diabetic (IDDM) patients with microalbuminuria or diabetic nephropathy. GFR was measured after a single intravenous injection of 3.7 MBq 51Cr-EDTA by determining the radioactivity in venous blood samples taken 5, 7, 10, 15, 30, 45, 60, 90, 120, 150, 180, 200, 220, and 240 min after the injection. Rate of decline in GFR was assessed using 12 (6-17) determinations of GFR over a period of time of 8 (4-10) years. Mean (SD) GFRT was 123 (21) ml x min(-1) compared to GFR(IV) 123 (21) ml x min(-1) (NS) and GFR(I) 115 (17) ml x min(-1) (p < 0.00001). The mean difference (95% limits of agreement) between GFR(T) and GFR(IV) was +0.6 (-16.6 to +17.7) ml x min(-1), and between GFR(T) and GFR(I) +8.0 (-6.0 to +22.2) ml x min(-1). The difference between GFR(T) and GFR(I) was significantly correlated with their mean value (r = 0.56, p < 0.00001), indicating increasing underestimation by GFR(I) with increasing GFR levels. The mean (SD) rate of decline in GFR(T) was 2.3 (3.9) ml x min(-1) x year(-1), compared to a mean rate of decline in GFR(IV) of 2.4 (3.6) ml x min(-1) x year(-1) (NS), and a mean rate of decline in GFR(I) of 2.2 (3.5) ml x min(-1) x year(-1) (NS). The mean difference (95% limits of agreement) between rate of decline in GFR(T) and rate of decline in GFR(IV) was +0.16 (-1.59 to +1.91) ml x min(-1) x year(-1), and between rate of decline in GFR(T) and rate of decline in GFR(I) -0.01 (-1.64 to +1.61) ml x min(-1) x year(-1), respectively. In conclusion, our cross-sectional study revealed a close agreement between GFR(T) and GFR(IV) with acceptable limits of agreement (precision), while GFR(I) lacked accuracy. However, a close agreement between rate of decline in GFR(T) and rate of decline in GFR(IV), and between rate of decline in GFR(T) and rate of decline in GFR(I), with acceptable limits of agreement (precision), suggests that both simplified methods are applicable for long-term follow-up.


Asunto(s)
Nefropatías Diabéticas/fisiopatología , Ácido Edético , Tasa de Filtración Glomerular , Radioisótopos de Cromo , Estudios Transversales , Nefropatías Diabéticas/sangre , Ácido Edético/sangre , Ácido Edético/farmacocinética , Femenino , Humanos , Estudios Longitudinales , Masculino
16.
Kidney Int ; 52(5): 1369-74, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9350661

RESUMEN

We investigated the effect of acute lowering of blood pressure (BP) upon glomerular filtration rate (GFR) in hypertensive non-insulin-dependent diabetes mellitus (NIDDM) patients, 14 with diabetic nephropathy and 12 with normoalbuminuria. The study was performed twice with the subjects receiving an intravenous injection of either clonidine (150 to 225 micrograms) or saline (0.154 mmol/liter). We assessed GFR, albuminuria, and BP. The two groups were well matched with respect to demographic data, baseline GFR and BP. Clonidine induced similar reductions in mean arterial blood pressure 19 (SE +/- 4) and 21 (SE +/- 3) mm Hg in patients with and without nephropathy, respectively. In the nephropathy group GFR diminished in average from 90 (SE +/- 6) to 81 (SE +/- 7) ml/min/1.73 m2 (P = 0.006), fractional clearance of albumin (x 10(-6)) declined from a geometric mean of 219 (antilog SE /divided by 1.3) to 186 (antilog SE /divided by 1.3) (P = 0.04), and four patients had a complete pressure-passive vasculature, defined as delta GFR% = delta MABP%. A significant correlation between relative reductions in MABP and GFR (r = 0.78, P < 0.001) was demonstrated in albuminuric patients. None of the normoalbuminuric patients had a complete pressure-passive vasculature and there were no significant differences in GFR between the two examinations, but five had abnormal autoregulation of GFR. Mean difference between changes in GFR (95% confidence interval) between the nephropathic and normoalbuminuric group was 5.5 (divided by 2.7 to 13.7) ml/min/1.73 m2 (P = 0.18). Our study suggests that hypertensive NIDDM patients, particularly patients with nephropathy, frequently suffer from impaired or abolished autoregulation of GFR.


Asunto(s)
Diabetes Mellitus Tipo 2/fisiopatología , Nefropatías Diabéticas/fisiopatología , Tasa de Filtración Glomerular , Hipertensión/fisiopatología , Adulto , Anciano , Glucemia/análisis , Clonidina/uso terapéutico , Estudios Cruzados , Ácido Edético/farmacocinética , Femenino , Homeostasis , Humanos , Hipertensión/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Método Simple Ciego
17.
Exp Clin Immunogenet ; 14(4): 273-80, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9523163

RESUMEN

A novel antigen was identified by the cross-reactivity of the anti-CD30 antibody Ki-1. This 57-kD intracellular Ki-1 antigen (Ki-1/57) is induced upon activation of leukocytes and is transported to the nuclear compartment. We describe the partial cloning and sequencing of the Ki-1/57 cDNA from a lambda gt 11-cDNA library derived from the Hodgkin-analogous cell line L540. New monoclonal antibodies were produced against the recombinant Ki-1/57 protein fragment which were used to confirm that the Ki-1/57 antigen is associated with kinase activity and is expressed in a variety of tumor cell lines and in activated but not resting leukocytes. The Ki-1/57 gene was mapped to the bands 9q22.3-31 of human chromosome 9. This is an area which appears to be associated with secondary chromosomal aberrations in acute myeloid leukemias.


Asunto(s)
Antígeno Ki-1/genética , Secuencia de Aminoácidos , Animales , Baculoviridae , Secuencia de Bases , Línea Celular , Bandeo Cromosómico , Cromosomas Humanos Par 9 , Clonación Molecular , ADN Complementario/química , Humanos , Hibridación Fluorescente in Situ , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Peso Molecular , Mapeo Restrictivo , Spodoptera
18.
Kidney Int Suppl ; 63: S49-53, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9407421

RESUMEN

Initiation of antihypertensive treatment in hypertensive non-insulin-dependent diabetic (NIDDM) patients with diabetic nephropathy induces a faster initial (0 to 6 months) and slower subsequent (6 months-end) decline in GFR [delta GFR (ml.min-1.1.73 m-2.month-1) approximately 1.5 vs. 0.4]. Whether this initial phenomenon is reversible (hemodynamic) or irreversible (structural damage) after prolonged antihypertensive treatment is not known. To elucidate these mechanisms we investigated 40 hypertensive NIDDM patients (age 61 +/- 7 years, mean +/- SD), known duration of diabetes 14 years (2 to 33 years) [median (range)] with diabetic nephropathy receiving antihypertensive treatment (angiotensin converting enzyme inhibition, N = 30) for 5 years (1 to 20 years). The following variables were measured the last day on antihypertensive treatment and one month after withdrawal of treatment; GFR (51Cr-EDTA), 24-hour arterial blood pressure (24 hr MABP, Takeda TM2420) and albuminuria (ELISA); the mean 24-hour MABP rose from 102 +/- 11 to 111 +/- 10 (P < 0.0001) and albuminuria [geometric mean (antilog SEM)] increased from 634 (1.3) to 1159 (1.2) (P < 0.0001), while GFR (mean +/- SD) remained unchanged (69 +/- 25 to 70 +/- 26 ml.min-1.1.73 m-2, P = 0.21), after withdrawal of antihypertensive treatment. A significant correlation between the relative change in the 24 hour MABP measurement and the relative change in GFR (r = 0.44, P < 0.01) was found. In conclusion, our results suggest that the faster initial decline in GFR after initiating antihypertensive treatment in hypertensive NIDDM patients with diabetic nephropathy is due to a irreversible effect, and should be accounted for when evaluating the beneficial effect of antihypertensive treatment on the progression of diabetic nephropathy in these patients.


Asunto(s)
Antihipertensivos/uso terapéutico , Nefropatías Diabéticas/fisiopatología , Hipertensión Renovascular/tratamiento farmacológico , Hipertensión Renovascular/fisiopatología , Adolescente , Adulto , Anciano , Albuminuria/tratamiento farmacológico , Albuminuria/orina , Presión Sanguínea/efectos de los fármacos , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad
19.
Kidney Int ; 50(2): 579-85, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8840289

RESUMEN

The aim of our study was to evaluate the diurnal relationship between arterial blood pressure and albuminuria, and some potential mechanisms responsible for impaired nocturnal blood pressure reduction (non-dippers, groups I and II) in diabetic nephropathy (DN). Twenty-four-hour ambulatory blood pressure, heart rate (HR) variation (autonomic nervous function) and extracellular fluid volume (ECV) were measured, and urine samples were collected three times during the corresponding day- and nighttimes in 47 insulin-dependent diabetic (IDDM) patients with DN. Mean arterial blood pressure (MABP) during the daytime [mm Hg, median (range)] was identical in group I [105 (96-137)], group II [109 (86-124)] and group III [dippers; average blood pressure reduction from day to night > 10%, 107 (93-132), P = NS], while the nighttime MABP differed [group I, 106 (95-144); group II, 100 (78-118); group III, 91 (76-118); P < 0.001]. No significant difference between the groups concerning the daytime or nighttime albuminuria [microgram/min; median (range)] was observed; [Day: group I, 1467 (235-3933); group II, 695 (170-6719); group III, 875 (228-3173). Night: group I, 1079 (279-4665); group II, 572 (113-3807); group III, 659 (81-2493)]. A significant correlation between MABP and albuminuria was demonstrated during day- (rho = 0.50, P < 0.0005) and nighttime (rho = 0.46, P < 0.005), while neither the absolute nor the relative changes in MABP from day to night correlated significantly with absolute or relative changes in albuminuria from day to night. The night/day ratio of HR was higher in group I [0.93 (0.76-1.09), median (range)] compared to group III [0.83 (0.74-1.02), P < 0.005] and a significant correlation between this ratio and the night/day ratio of MABP was found (rho = 0.54, P < 0.0005). ECV was about the same in the three groups. Our study indicated an association between blood pressure and albuminuria, but the mechanisms involved in the reduction of albuminuria from day to night was not unraveled. A relative lack of sympathetic withdrawal during sleep seems to be an important feature of nocturnal hypertension in diabetic nephropathy.


Asunto(s)
Albuminuria/complicaciones , Albuminuria/fisiopatología , Presión Sanguínea/fisiología , Ritmo Circadiano/fisiología , Nefropatías Diabéticas/complicaciones , Nefropatías Diabéticas/fisiopatología , Adulto , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/fisiopatología , Espacio Extracelular/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad
20.
Scand J Clin Lab Invest ; 56(5): 393-9, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8869661

RESUMEN

The acute effect of smoking upon arterial blood pressure, urinary albumin excretion rate, glomerular filtration rate and transcapillary escape rate of albumin were investigated in nine normotensive insulin-dependent diabetic patients with microalbuminuria, who had been smoking for 19 (range 4-30) years. In a prospective, open randomized cross-over design, patients were investigated with and without smoking three cigarettes per hour during a 5.5-h period. A rise in systolic blood pressure and heart rate (Takeda TM2420, median (range)) was observed during the smoking day (10(-11 to 14) mmHg and 8 (-1 to 19) beats min-1), compared to the non-smoking day (1 mmHg (-7 to 13) (p = 0.05) and 0 beats min-1 (-2 to 4) (p < 0.01)). Urinary albumin excretion rate (ELISA), glomerular filtration rate (plasma clearance of 51Cr-EDTA) and transcapillary escape rate of albumin (125I-albumin) remained the same with or without smoking. Our study suggests that heavy smoking induces an abrupt rise in systolic blood pressure and heart rate, while vascular leakage of albumin and glomerular filtration rate remain unaltered in normotensive insulin-dependent diabetic patients with microalbuminuria who had been smoking for several years.


Asunto(s)
Albuminuria/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiología , Hemodinámica/efectos de los fármacos , Riñón/efectos de los fármacos , Riñón/fisiología , Fumar/efectos adversos , Adulto , Albuminuria/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad
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