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1.
Mech Ageing Dev ; 205: 111686, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35609733

RESUMO

Recent evidence demonstrates that Crocus sativus L. (saffron) counteracts oxidative stress, mitochondrial dysfunction and neuroinflammation, closely linked to initiation and progression of major brain pathologies. Interestingly, saffron constituents such as crocin, crocetin and safranal can exert antioxidant or toxic effects depending on their endogenous concentration. According to the hormesis principles, at low dose they act as antioxidants in a wide range of brain diseases by upregulating Nrf2 signaling pathway and the expression of vitagenes, such as NAD(P)H-quinone oxidoreductase (NQO1), glutathione transferase (GT), heme oxygenase-1 (HO-1), sirtuin-1 (Sirt1) and thioredoxin (Trx) system. Importantly, neuronal dysregulation of Nrf2 pathway can be a prominent cause of selective susceptibility, under neuroinflammatory conditions, due to the high vulnerability of brain cells to oxidative stress. Here we discuss natural inducers from saffron targeting Nrf2/vitagene pathway for development of new therapeutical strategies to suppress oxidative stress and neuroinflammation and consequently cognitive dysfunction. In this review we also focus on the hormetic effect of saffron active constituents, summarizing their neuroprotective and anti-neuroinflammatory properties, as well as pharmacological perspectives in brain disorders.


Assuntos
Encefalopatias , Crocus , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Humanos , Fator 2 Relacionado a NF-E2 , Oxirredução , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
2.
Rev Sci Instrum ; 92(8): 083510, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34470385

RESUMO

Thoriated tungsten cathodes, first studied by Langmuir [Phys. Rev. 22, 357-398 (1923)], are used in many applications as efficient electron emitters. However, neutral pressure gauges with thoriated tungsten cathodes (or ASDEX pressure gauges) are not reliable when operated in the strong magnetic field of fusion devices of several Tesla. We have identified the reason for the bad performance in the Wendelstein 7-X stellarator during the operation of several 100 s. Not only were slow, creeping mechanical deformations of the cathodes observed, but also fast events, such as sudden short circuits. The temperature of the cathode is often much higher (about 2400 K) than the maximum value recommended by Langmuir [Phys. Rev. 22, 357-398 (1923)] (about 1900 K). Our test in a superconducting magnet revealed that for a long-pulse operation of 30 min or more in a 3.1 T field, there is an additional effect. We observed that the cathodes required a very high heating current after 6 h of operation. As a consequence, the possible temperature range of the thoriated tungsten cathodes became very small near to an experimentally determined failure limit. In fusion devices with long-pulse operation or in reactors, new cathode types must be used. We give a brief overview of alternative designs that are currently under development.

3.
Rev Sci Instrum ; 91(4): 043504, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357759

RESUMO

A new type of in-vessel Penning gauge, the Wisconsin In Situ Penning (WISP) gauge, has been developed and successfully operated in the Wendelstein 7-X (W7-X) island divertor baffle and vacuum vessel. The capacity of the quantitative measurements of the neutral reservoir for light impurities, in particular, helium, is important for tokamaks as well as stellarator divertors in order to avoid fuel dilution and radiative energy loss. Penning gauges assisted by spectroscopy are a powerful tool to obtain the total neutral pressure as well as fractional neutral pressures of specific impurities. The WISP gauge is a miniaturized Penning gauge arrangement, which exploits the ambient magnetic field of magnetic confinement fusion experiments to establish the Penning discharge. Then, in situ spectroscopy is conducted to separate the fractional neutral pressures of hydrogen, helium, and possibly also other impurities. The WISP probe head was qualified using the magnetic field of the Magnetized Dusty Plasma Experiment at Auburn University between 0.25 T and 3.5 T [E. Thomas et al., J. Plasma Phys. 81, 345810206 (2015)]. The in-depth quantitative evaluation for hydrogen and helium will be shown as well as an exploration of nitrogen, argon, and neon. A power law scaling between current I and pressure p, I = f(Gas,V) · pn(Gas, B), was shown. The factor f is gas and anode potential dependent, while n is gas and magnetic field strength dependent. Pressure measurements from 0.1 mbar and down to 1 × 10-5 mbar were achieved, demonstrating a reliable operating range for relevant pressure levels in the divertor and main vessel regions in current and future fusion devices, with a time resolution of up to 1 kHz. The lowest achievable pressure measurement increases with an increase in B and can be shifted with the anode potential V. At W7-X, the WISP probe head was mounted on an immersion tube setup that passes through the cryostat and places the probe head close to the plasma. Two probe heads were positioned in different divertor pump gaps, top and bottom, and one close to the plasma on the midplane in one module. The gauges were in situ calibrated together with the ASDEX pressure gauges [G. Haas and H.-S. Bosch, Vacuum 51, 39 (1998)]. Data were taken during the entire operation phase 1.2b, and measurements were coherent with other neutral gas pressure gauges. For the spectroscopic partial pressure measurements, channels of a spectroscopic detection system based on photo-multipliers, a so-called filterscope [R. J. Colchin et al., Rev. Sci. Instrum. 74, 2068 (2003)], provided by the Oak Ridge National Lab were used.

4.
Rev Sci Instrum ; 90(9): 093501, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31575247

RESUMO

Fusion reactors and long pulse fusion experiments heavily depend on a continuous fuel cycle, which requires detailed monitoring of exhaust gases. We have used a diagnostic residual gas analyzer (DRGA) built as a prototype for ITER and integrated it on the most advanced stellarator fusion experiment, Wendelstein 7-X (W7-X). The DRGA was equipped with a sampling tube and assessed for gas time of flight sample response, effects of magnetic field on gas detection and practical aspects of use in a state of the art fusion environment. The setup was successfully commissioned and operated and was used to observe the gas composition of W7-X exhaust gases. The measured time of flight gas response was found to be in the order of a second for a 7 m sample tube. High values of magnetic field were found to affect the partial pressure readings of the DRGA and suggest that additional shielding is necessary in future experimental campaigns.

5.
Transplant Proc ; 50(10): 3211-3215, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30577187

RESUMO

BACKGROUND: An analysis of 2 kidney transplants from the same donor at the same center enables us to analyze the influence of risk factors on the outcome of the grafts in different recipients. METHODS: We retrospectively analyzed 88 kidneys from 44 donors that were implanted in 88 recipients at our institution between 2007-2016. We defined unsatisfactory outcome as glomerular filtration rate <30 mL/min/1.73 m2 allograft loss or recipient death within the first year after transplantation. Fifty-three kidneys were allocated and age-matched to donors above the age of 65 years (via Eurotransplant Senior Program or center offer). We compared kidney pairs with satisfactory outcome in both recipients (group A) to pairs with divergent outcome (group B) and unsatisfactory outcome in both recipients (group C). RESULTS: Thirty-four grafts (17 donors) had a satisfactory outcome for both recipients (group A), and 16 grafts (8 donors) had an unsatisfactory outcome for both recipients (group C). Donor age was significantly higher in group C vs group A (67.5 ± 6.7 vs 56.4 ± 16.0 years, P = .010). The 19 donors donating 1 kidney with satisfactory and the other with unsatisfactory outcome were 67.4 ± 10.7 years old (group B). A severe surgical complication occurred more often in recipients with an unsatisfactory outcome in comparison to patients with a satisfactory outcome. CONCLUSION: Donor age is an important risk factor for an unsatisfactory outcome, either in one or both kidneys of the same donor.


Assuntos
Sobrevivência de Enxerto , Transplante de Rim/métodos , Doadores de Tecidos , Adulto , Fatores Etários , Idoso , Aloenxertos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Doadores de Tecidos/provisão & distribuição , Transplante Homólogo , Resultado do Tratamento
6.
Rev Sci Instrum ; 89(3): 033503, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29604784

RESUMO

We report here on a potentially significant improvement in the design of neutral pressure gauges of the so-called ASDEX-type which were first used in the Axially Symmetric Divertor EXperiment (ASDEX). Such gauges are considered state-of-the-art and are in wide use in fusion experiments, but they nonetheless suffer from a relatively high failure rate when operated at high magnetic field strengths for long times. This is therefore a significant concern for long-pulse, high-field experiments such as Wendelstein 7-X (W7-X) and ITER. The new design is much more robust. The improvement is to use a LaB6 crystal instead of a tungsten wire as the thermionic emitter of electrons in the gauge. Such a LaB6 prototype gauge was successfully operated for a total of 60 h in B = 3.1 T, confirming the significantly improved robustness of the new design and qualifying it for near-term operation in W7-X. With the LaB6 crystal, an order of magnitude reduction in heating current is achieved, relative to the tungsten filament based gauges, from 15-20 A to 1-2 A. This reduces the Lorenz forces and the heating power by an order of magnitude also and is presumably the reason for the much improved robustness. The new gauge design, test environment setup at the superconducting magnet, and results from test operation are described.

7.
Brain Struct Funct ; 223(5): 2287-2302, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29473106

RESUMO

The (pro)renin receptor [(P)RR], also known as ATP6AP2 [ATPase 6 accessory protein 2], is highly expressed in the brain. ATP6AP2 plays a role in early brain development, adult hippocampal neurogenesis and in cognitive functions. Lack of ATP6AP2 has deleterious effects, and mutations of ATP6AP2 in humans are associated with, e.g. X-linked intellectual disability. However, little is known about the effects of over-expression of ATP6AP2 in the adult brain. We hypothesized that mice over-expressing ATP6AP2 in the brain might exhibit altered neuroanatomical features and behavioural responses. To this end, we investigated heterozygous transgenic female mice and confirmed increased levels of ATP6AP2 in the brain. Our data show that over-expression of ATP6AP2 does not affect adult hippocampal neurogenesis, exercise-induced cell proliferation, or dendritic spine densities in the hippocampus. Only a reduced ventricular volume on the gross morphological level was found. However, ATP6AP2 over-expressing mice displayed altered exploratory behaviour with respect to the hole-board and novel object recognition tests. Moreover, primary adult hippocampal neural stem cells over-expressing ATP6AP2 exhibit a faster cell cycle progression and increased cell proliferation. Together, in contrast to the known deleterious effects of ATP6AP2 depletion, a moderate over-expression results in moderate behavioural changes and affects cell proliferation rate in vitro.


Assuntos
Comportamento Animal/fisiologia , Hipocampo/citologia , Hipocampo/fisiologia , Neurônios/citologia , ATPases Translocadoras de Prótons/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Ciclo Celular/genética , Proliferação de Células/genética , Ventrículos Cerebrais/anatomia & histologia , Adaptação à Escuridão/genética , Espinhas Dendríticas/metabolismo , Proteínas do Domínio Duplacortina , Epêndima/metabolismo , Comportamento Exploratório , Hipocampo/diagnóstico por imagem , Histonas/metabolismo , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/metabolismo , Neurogênese/genética , Neuropeptídeos/metabolismo , ATPases Translocadoras de Prótons/genética , Receptores de Superfície Celular/genética , Reconhecimento Psicológico/fisiologia , Caracteres Sexuais
8.
Mucosal Immunol ; 11(1): 273-289, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28295019

RESUMO

Matrix protein 2 ectodomain (M2e) is considered an attractive component of a broadly protective, universal influenza A vaccine. Here we challenge the canonical view that antibodies against M2e are the prime effectors of protection. Intranasal immunizations of Balb/c mice with CTA1-3M2e-DD-generated M2e-specific memory CD4 T cells that were I-Ad restricted and critically protected against infection, even in the complete absence of antibodies, as observed in JhD mice. Whereas some M2e-tetramer-specific memory CD4 T cells resided in spleen and lymph nodes, the majority were lung-resident Th17 cells, that rapidly expanded upon a viral challenge infection. Indeed, immunized IL-17A-/- mice were significantly less well protected compared with wild-type mice despite exhibiting comparable antibody levels. Similarly, poor protection was also observed in congenic Balb/B (H-2b) mice, which failed to develop M2e-specific CD4 T cells, but exhibited comparable antibody levels. Lung-resident CD69+ CD103low M2e-specific memory CD4 T cells were αß TCR+ and 50% were Th17 cells that were associated with an early influx of neutrophils after virus challenge. Adoptively transferred M2e memory CD4 T cells were strong helper T cells, which accelerated M2e- but more importantly also hemagglutinin-specific IgG production. Thus, for the first time we demonstrate that M2e-specific memory CD4 T cells are broadly protective.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Vírus da Influenza A/imunologia , Infecções por Orthomyxoviridae/imunologia , Proteínas da Matriz Viral/imunologia , Animais , Anticorpos Antivirais/sangue , Antígenos de Histocompatibilidade Classe II/metabolismo , Hibridomas , Memória Imunológica , Interleucina-17/genética , Interleucina-17/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Ligação Proteica , Domínios Proteicos/genética , Vacinação , Proteínas da Matriz Viral/genética
9.
Rev Sci Instrum ; 87(11): 11E529, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27910409

RESUMO

Direct measurements of the helium (He) fractional neutral pressure in the neutral gas around fusion devices is challenging because of the small mass difference between the abundant D2 molecules and the He ash which will be produced by deuterium-tritium fusion. To study He exhaust, an in situ Penning gauge system is being developed at UW-Madison that is optimized for good pressure and high spectroscopic sensitivity. Three different anode geometries have been studied regarding their vacuum electrostatic fields, light output, and ion current. The light output of the two new anode configurations are at least one order of magnitude above the currently available designs, hence improving the spectroscopic sensitivity at similar total neutral pressure resolution.

10.
Rofo ; 185(5): 434-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23440645

RESUMO

PURPOSE: In 2011 a nationwide outbreak of Shiga toxin-producing E. coli (STEC) O104:H4 infection occurred in Germany with severe hemorrhagic colitis and hemolytic-uremic syndrome (HUS). We defined abdominal radiologic findings in these patients and correlated them with clinical parameters. MATERIALS AND METHODS: 23 patients (7 men; age: 48 ± 19 years) with O104:H4 colitis and/or HUS received abdominal CT (n = 12) or radiographs (n = 11). Colonic distension, air-fluid levels, and free intraabdominal air were assessed. Colonic wall thickening, contrast enhancement, pericolic stranding, and ascites were evaluated on CT. Laboratory parameters and clinical presentation were reviewed. Chi-square test, Student's t-test, McNemar's test and Spearman correlation were performed. RESULTS: Colonic lumen distension was seen in 16/23 patients (69.6 %). The ascending colon (11/23 patients; 47.8 %) and transverse colon (12/23 patients; 52.2 %) were dilated significantly more often (p = 0.006 and p = 0.003, respectively) than the descending colon (1/23; 4.3 %). All 12 patients undergoing CT scanning had abnormally thickened colonic wall segments, 3 (25 %) had pancolic involvement and 9 (75 %) had segmental involvement. The descending colon was predominantly affected (11/12 patients; 91.7 %) and thickened significantly more often than other colonic segments (p < 0.001). CONCLUSION: The segmental type of STEC O104:H4 colitis mainly affects the descending colon with upstream distension of the transverse/ascending colon and differs from other types of colitis.


Assuntos
Colite/diagnóstico por imagem , Colite/microbiologia , Escherichia coli Êntero-Hemorrágica , Infecções por Escherichia coli/diagnóstico por imagem , Infecções por Escherichia coli/microbiologia , Colite/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Infecções por Escherichia coli/epidemiologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia
11.
Internist (Berl) ; 53(12): 1420-30, 2012 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-23179596

RESUMO

Shiga toxin-associated hemolytic uremic syndrome (HUS) is an entity of thrombotic microangiopathy characterized by hemolytic anemia, thrombocytopenia, central nervous symptoms, and renal insufficiency. In May 2011, an outbreak of enterohemorrhagic Escherichia coli (EHEC; O104:H4) occurred in Northern Germany. By the end of July 2011, the outbreak was over but nearly 4000 patients had an EHEC infection, 855 cases of hemolytic-uraemic syndrome were reported to the Robert Koch Institute, and there were 35 (4.1%) deaths. Shiga toxin-induced HUS is a rare disease and no controlled clinical trials on therapeutic options are available. First analyses of this outbreak suggest that therapeutic plasma exchange, which was used in the majority of patients, had no benefit and might even be harmful. The role of eculizumab, a monoclonal antibody which inhibits the complement system, is being examined in a multicenter study: the results have not been published yet. Promising is the use of some antibiotics. This would change a paradigm that antibiotics should be avoided. Ongoing and future analyses of the epidemic should be awaited before a final recommendation regarding the different treatment strategies can be made.


Assuntos
Antibacterianos/uso terapêutico , Surtos de Doenças/prevenção & controle , Surtos de Doenças/estatística & dados numéricos , Síndrome Hemolítico-Urêmica/mortalidade , Síndrome Hemolítico-Urêmica/terapia , Troca Plasmática/mortalidade , Escherichia coli Shiga Toxigênica , Síndrome Hemolítico-Urêmica Atípica , Alemanha/epidemiologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Fatores de Risco , Análise de Sobrevida , Taxa de Sobrevida , Resultado do Tratamento
14.
Hamostaseologie ; 28(1-2): 85-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18278168

RESUMO

UNLABELLED: Epidemiological studies indicate that the consumption of soy-containing food may prevent or slow-down the development of cardiovascular disease. In endothelial cells application of a soy extract or a combination of the most abundant soy isoflavones genistein and daidzein both inhibited apoptosis, a driving force in atherosclerosis development, when applied in combination with oxidized LDL or homocysteine. Proteome analysis revealed that the stressor-induced alteration of protein expression profile was reversed by the soy extract or the genistein/daidzein mixture. Only few protein entities that could be functionally linked to mitochondrial dysfunction were regulated in common by both application forms of isoflavones. A dietary intervention with isoflavone-enriched soy extract in postmenopausal women, who generally show strongly increased cardiovascular risk due to diminished estrogen production, led to significant alterations in the steady state levels of proteins from mononuclear blood cells. The proteins identified by proteome analysis revealed that soy isoflavones may increase the anti-inflammatory response in blood mononuclear cells thereby contributing to the atherosclerosis-preventive activities of a soy-rich diet. CONCLUSION: By proteome analysis protein targets were identified in vitro in endothelial cells that respond to soy isoflavones and that may decipher molecular mechanisms through which soy products exert their protective effects in the vasculature.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Glycine max , Isoflavonas/uso terapêutico , Leucócitos/fisiologia , Aterosclerose/prevenção & controle , Doenças Cardiovasculares/fisiopatologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Endotélio Vascular/fisiopatologia , Humanos , Leucócitos/efeitos dos fármacos
15.
Kidney Int ; 73(5): 643-50, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18033241

RESUMO

The C57BL/6 mouse strain serves as the genetic background of many transgenic and gene knockout models; however, this strain appears to be resistant to hypertension-induced renal injury. We developed a new model of hypertensive end-organ damage in C57BL/6 mice by combining deoxycorticosterone acetate (DOCA) and salt with angiotensin II infusion. The systolic blood pressure (SBP) was significantly elevated in DOCA salt-angiotensin II mice compared to control mice or mice treated individually with DOCA salt or angiotensin II. Hypertensive glomerular damage, increased expression of profibrotic and inflammatory genes, albuminuria, tubular casts, increased plasma cholesterol, cardiac hypertrophy, and fibrosis were found in mice treated with DOCA salt-angiotensin II. The SBP in the angiotensin II-infused group was further increased by increasing the infusion rate; only mild injury was observed in these mice, suggesting that blood pressure was not a causal factor. Removal of DOCA and the angiotensin pump lowered blood pressure to normal; however, albuminuria along with the glomerular and cardiac damage did not completely resolve. Our study describes a new model of hypertensive end-organ damage and repair in C57BL/6 mice.


Assuntos
Modelos Animais de Doenças , Hipertensão/complicações , Falência Renal Crônica/etiologia , Camundongos , Angiotensina II/toxicidade , Animais , Pressão Sanguínea , Peso Corporal , Desoxicorticosterona/toxicidade , Hipertensão/induzido quimicamente , Falência Renal Crônica/patologia , Falência Renal Crônica/fisiopatologia , Glomérulos Renais/fisiopatologia , Glomérulos Renais/ultraestrutura , Masculino , Mineralocorticoides/toxicidade , Miocárdio/patologia , Proteinúria/etiologia , Vasoconstritores/toxicidade
16.
Nephrol Dial Transplant ; 22(10): 3055-60, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17640943

RESUMO

BACKGROUND: The glomeruli in the non-clipped kidney of rats with 2-kidney, 1-clip hypertension are a classical model for studying the mechanisms of glomerular injury. METHODS: In the present study, we compared the glomerular expression of PAI-1 and collagen I alpha1 mRNA from glomeruli isolated by the classic technique of sieving with the recently developed technique of tissue laser microdissection. For quantification of mRNA from both methods, real-time PCR was used. RESULTS: Real-time PCR revealed a 9.0 +/- 1.3- and a 7.1 +/- 0.2-fold induction of PAI-1 and collagen I alpha 1, respectively, in the glomeruli from hypertensive rats isolated by sieving. However, in situ hybridization and microdissection revealed that expression of both mRNAs was mainly from the Bowman's capsule and not from the glomerular tuft (10.7 +/- 1.3- and 7.2 +/- 0.6-fold higher induction in whole glomeruli compared with tuft alone). CONCLUSION: This emphasizes that studies focusing on processes in the mesangium, endothelial cells or podocytes should not rely on glomeruli obtained by sieving. Rather, a technique like the laser microdissection or in situ hybridization should be applied which allows the clear separation of different glomerular and periglomerular compartments.


Assuntos
Cápsula Glomerular/metabolismo , Regulação da Expressão Gênica , Hipertensão Renovascular/diagnóstico , Glomérulos Renais/metabolismo , Animais , Pressão Sanguínea , Colágeno Tipo I/metabolismo , Hipertensão Renovascular/patologia , Hibridização In Situ , Masculino , Modelos Biológicos , Reação em Cadeia da Polimerase , RNA/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Kidney Int ; 72(6): 725-30, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17597696

RESUMO

Recently, a (pro)renin receptor has been identified which mediates profibrotic effects independent of angiotensin II. Because antihypertensive therapy induces renal injury in the clipped kidney of two kidney-1-clip hypertensive rats, we examined the regulation of renin and the (pro)renin receptor in this model. Hypertensive Goldblatt rats were treated with increasing doses of the vasopeptidase inhibitor AVE 7688 after which the plasma renin and prorenin as well as the renal renin and (pro)renin receptor expression were measured. The vasopeptidase inhibitor dose-dependently lowered blood pressure, which was associated with a massive increase in plasma prorenin and renin as well as increased renal renin expression. The (pro)renin receptor was upregulated in the clipped kidney of the Goldblatt rat indicating a parallel upregulation of renin and its receptor in vivo. Immunohistochemistry showed a redistribution of renin upstream from the glomerulus in preglomerular vessels and renin staining in tubular cells. Expression of the (pro)renin receptor was increased in the vessels and tubules. This upregulation was associated with thickening of renin-positive vessels and tubulointerstitial damage. We propose that renin and the (pro)renin receptor may play a profibrotic role in the clipped kidney of Goldblatt rats treated for hypertension.


Assuntos
Compostos Heterocíclicos com 3 Anéis/farmacologia , Hipertensão Renovascular/tratamento farmacológico , Hipertensão Renovascular/metabolismo , Pró-Fármacos/farmacologia , Receptores de Superfície Celular/metabolismo , Renina/metabolismo , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Hipertensão Renovascular/patologia , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Instrumentos Cirúrgicos , Regulação para Cima/efeitos dos fármacos , Receptor de Pró-Renina
18.
Kidney Int ; 71(5): 374-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17315004

RESUMO

ACE inhibitors or AT(1) antagonists are powerful therapeutic strategies to slow the progression of renal disease. However, they provide only imperfect protection since they cannot always prevent end-stage renal failure. Innovative approaches are needed to keep patients with chronic kidney disease off dialysis. Blockade of the aldosterone pathway may prove to be such a beneficial therapeutic concept.


Assuntos
Falência Renal Crônica/prevenção & controle , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Potássio/metabolismo , Sódio/metabolismo , Aldosterona/fisiologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Humanos , Hipertensão/tratamento farmacológico
19.
Am J Physiol Renal Physiol ; 292(2): F876-87, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17062848

RESUMO

The present study examined the pathogenesis of interstitial inflammation and fibrosis in antihypertensively treated rats with two-kidney, one-clip hypertension. Hypertensive rats were randomized into four groups: no treatment and moderate, intermediate, and intensified lowering of blood pressure with increasing doses of a vasopeptidase inhibitor for 6 wk. The vasopeptidase inhibitor dose dependently lowered blood pressure. The tubulointerstitial damage was accompanied by a diffuse infiltration of mononuclear cells and circumscript mononuclear inflammatory cell cluster formation consisting mainly of T cells and to a lesser degree of macrophages and B cells. Real-time PCR analyses showed a dose-dependent induction of MCP-1 and the Th1-type chemokines IP10 and Mig as well as their receptor CXCR3 and the Th1 cytokine IFN-gamma. In situ hybridization and laser microdissection revealed a strong expression of these Th1-associated transcripts in the clusters and, in the case of MCP-1, also diffusely in the interstitium. The inflammation was accompanied by the appearance of myofibroblasts and synthesis of the fibrogenic factor plasminogen activator inhibitor-1 as well as the collagenase matrix metalloproteinase-2, leading to collagen I upregulation and interstitial scarring. No inflammation or fibrosis was found in normotensive rats treated with the vasopeptidase inhibitor. The renal injury in the clipped kidney is accompanied by compartment-specific chemokine expression and cell cluster formation of Th1 specificity associated with upregulation of fibrogenic proteins and matrix metalloproteinases. These findings suggest that the Th1 chemokines IP10 and Mig as well as their receptor CXCR3 are potential targets for therapeutic interventions in ischemic nephropathy.


Assuntos
Anti-Hipertensivos/uso terapêutico , Quimiocinas/biossíntese , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Hipertensão Renovascular/tratamento farmacológico , Hipertensão Renovascular/imunologia , Células Th1/imunologia , Actinas/biossíntese , Animais , Quimiocina CCL2/biossíntese , Quimiocina CXCL10 , Quimiocina CXCL9 , Quimiocinas CXC/biossíntese , Creatinina/sangue , Fibrose , Expressão Gênica , Hipertensão Renovascular/patologia , Imuno-Histoquímica , Hibridização In Situ , Molécula 1 de Adesão Intercelular/biossíntese , Interferon gama/biossíntese , Rim/patologia , Masculino , Metaloproteinase 2 da Matriz/biossíntese , Osteopontina/biossíntese , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Ratos , Ratos Sprague-Dawley
20.
Eur J Clin Invest ; 36(8): 519-27, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16893373

RESUMO

Dyslipdemia is a common complication of chronic kidney disease (CKD) and contributes to high cardiovascular morbidity and mortality of CKD patients. Experimental studies have demonstrated that lipids induce glomerular and tubulointerstitial injury and that lipid-lowering treatments ameliorate renal injury. Therapy with statins not only has the potential to lower cardiovascular morbidity and mortality in patients with CKD but also to slow progression of renal disease. Whereas the guidelines for treatment of hyperlipidaemia in nonrenal patients are based on prospective, randomized, placebo-controlled mega-trials, such data are not available for CKD patients. This review outlines the limited information currently available on the effect of statins among patients with CKD and summarizes the ongoing randomized trials designed to address this question.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Nefropatias/tratamento farmacológico , Colesterol/biossíntese , Doença Crônica , Ensaios Clínicos como Assunto , Humanos , Hipercolesterolemia/complicações , Nefropatias/complicações , Falência Renal Crônica/complicações , Falência Renal Crônica/tratamento farmacológico , Transplante de Rim , Proteinúria/complicações , Resultado do Tratamento
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