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1.
J Exp Bot ; 74(5): 1358-1371, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36609593

RESUMO

Aluminium (Al) toxicity is one of the major constraints for crop growth and productivity in most of the acid soils worldwide. The primary lesion of Al toxicity is the rapid inhibition of root elongation. The root apex, especially the transition zone (TZ), has been identified as the major site of Al accumulation and injury. The signalling, in particular through phytohormones in the root apex TZ in response to Al stress, has been reported to play crucial roles in the regulation of Al-induced root growth inhibition. The binding of Al in the root apoplast is the initial event leading to inhibition of root elongation. Much progress has been made during recent years in understanding the molecular functions of cell wall modification and Al resistance-related genes in Al resistance or toxicity, and several signals including phytohormones, Ca2+, etc. have been reported to be involved in these processes. Here we summarize the recent advances in the understanding of Al-induced signalling and regulatory networks in the root apex involved in the regulation of Al-induced inhibition of root growth and Al toxicity/resistance. This knowledge provides novel insights into how Al-induced signals are recognized by root apical cells, transmitted from the apoplast to symplast, and finally initiate the defence system against Al. We conclude that the apoplast plays a decisive role in sensing and transmitting the Al-induced signals into the symplast, further stimulating a series of cellular responses (e.g. exudation of organic acid anions from roots) to adapt to the stress. We expect to stimulate new research by focusing on the signalling events in the root apex in response to Al stress, particularly taking into consideration the signal transduction between the meristem zone, TZ, and elongation zone and the apoplast and symplast.


Assuntos
Reguladores de Crescimento de Plantas , Raízes de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/metabolismo , Alumínio/toxicidade , Alumínio/metabolismo , Meristema/metabolismo , Transdução de Sinais
2.
Clin Immunol ; 236: 108961, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35227871

RESUMO

Patients receiving maintenance dialysis (MD) are vulnerable to COVID-19-related morbidity and mortality. Currently, data on SARS-CoV-2-specific cellular and humoral immunity post-vaccination in this population are scarce. We conducted a prospective single-center study exploring the specific cellular (interferon-γ and interleukin-2 ELISpot assays) and humoral immune responses (dot plot array and chemiluminescent microparticle immunoassay [CMIA]) at 4 weeks and 6 weeks following a single dose or a complete homologous dual dose SARS-CoV-2 vaccine regimen in 60 MD patients (six with a history of COVID-19). Our results show that MD patients exhibit a high seroconversion rate (91.7%) but the anti-spike IgG antibodies (CMIA) tend to wane rapidly after full immunization. Only 51.7% of the patients developed T cell immune response. High anti-spike IgG antibodies may predict a better cellular immunity. While patients with prior COVID-19 showed the best response after one, SARS-CoV-2-naïve patients may benefit from a third vaccine injection.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Anticorpos Antivirais , Vacina BNT162 , COVID-19/prevenção & controle , Humanos , Imunidade Humoral , Estudos Prospectivos , RNA Mensageiro , Diálise Renal , SARS-CoV-2
3.
J Transl Med ; 20(1): 204, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538495

RESUMO

BACKGROUND: Post-cardiac surgery acute kidney injury (AKI) is associated with increased mortality. A high-protein meal enhances the renal blood flow and glomerular filtration rate (GFR) and might protect the kidneys from acute ischemic insults. Hence, we assessed the effect of a preoperative high-oral protein load on post-cardiac surgery renal function and used experimental models to elucidate mechanisms by which protein might stimulate kidney-protective effects. METHODS: The prospective "Preoperative Renal Functional Reserve Predicts Risk of AKI after Cardiac Operation" study follow-up was extended to postoperative 12 months for 109 patients. A 1:2 ratio propensity score matching method was used to identify a control group (n = 214) to comparatively evaluate the effects of a preoperative protein load and standard care. The primary endpoints were AKI development and postoperative estimated GFR (eGFR) loss at 3 and 12 months. We also assessed the secretion of tissue inhibitor of metalloproteases-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7), biomarkers implicated in mediating kidney-protective mechanisms in human kidney tubular cells that we exposed to varying protein concentrations. RESULTS: The AKI rate did not differ between the protein loading and control groups (13.6 vs. 12.3%; p = 0.5). However, the mean eGFR loss was lower in the former after 3 months (0.1 [95% CI - 1.4, - 1.7] vs. - 3.3 [95% CI - 4.4, - 2.2] ml/min/1.73 m2) and 12 months (- 2.7 [95% CI - 4.2, - 1.2] vs - 10.2 [95% CI - 11.3, - 9.1] ml/min/1.73 m2; p < 0.001 for both). On stratification based on AKI development, the eGFR loss after 12 months was also found to be lower in the former (- 8.0 [95% CI - 14.1, - 1.9] vs. - 18.6 [95% CI - 23.3, - 14.0] ml/min/1.73 m2; p = 0.008). A dose-response analysis of the protein treatment of the primary human proximal and distal tubule epithelial cells in culture showed significantly increased IGFBP7 and TIMP-2 expression. CONCLUSIONS: A preoperative high-oral protein load did not reduce AKI development but was associated with greater renal function preservation in patients with and without AKI at 12 months post-cardiac surgery. The potential mechanisms of action by which protein loading may induce a kidney-protective response might include cell cycle inhibition of renal tubular epithelial cells. Clinical trial registration ClinicalTrials.gov: NCT03102541 (retrospectively registered on April 5, 2017) and ClinicalTrials.gov: NCT03092947 (retrospectively registered on March 28, 2017).


Assuntos
Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos , Injúria Renal Aguda/etiologia , Biomarcadores , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Estudos de Coortes , Feminino , Taxa de Filtração Glomerular , Humanos , Rim/fisiologia , Masculino , Complicações Pós-Operatórias , Estudos Prospectivos , Inibidor Tecidual de Metaloproteinase-2
4.
Am J Physiol Lung Cell Mol Physiol ; 320(4): L590-L599, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33237794

RESUMO

Despite the pandemic status of COVID-19, there is limited information about host risk factors and treatment beyond supportive care. Immunoglobulin G (IgG) could be a potential treatment target. Our aim was to determine the incidence of IgG deficiency and associated risk factors in a cohort of 62 critically ill patients with COVID-19 admitted to two German ICUs (72.6% male, median age: 61 yr). Thirteen (21.0%) of the patients displayed IgG deficiency (IgG < 7 g/L) at baseline (predominant for the IgG1, IgG2, and IgG4 subclasses). Patients who were IgG-deficient had worse measures of clinical disease severity than those with normal IgG levels (shorter duration from disease onset to ICU admission, lower ratio of [Formula: see text] to [Formula: see text], higher Sequential Organ Failure Assessment score, and higher levels of ferritin, neutrophil-to-lymphocyte ratio, and serum creatinine). Patients who were IgG-deficient were also more likely to have sustained lower levels of lymphocyte counts and higher levels of ferritin throughout the hospital stay. Furthermore, patients who were IgG-deficient compared with those with normal IgG levels displayed higher rates of acute kidney injury (76.9% vs. 26.5%; P = 0.001) and death (46.2% vs. 14.3%; P = 0.012), longer ICU [28 (6-48) vs. 12 (3-18) days; P = 0.012] and hospital length of stay [30 (22-50) vs. 18 (9-24) days; P = 0.004]. Univariable logistic regression showed increasing odds of 90-day overall mortality associated with IgG-deficiency (odds ratio 5.14, 95% confidence interval 1.3-19.9; P = 0.018). IgG deficiency might be common in patients with COVID-19 who are critically ill, and warrants investigation as both a marker of disease severity as well as a potential therapeutic target.


Assuntos
COVID-19/virologia , Imunoglobulinas/deficiência , SARS-CoV-2/patogenicidade , Índice de Gravidade de Doença , Estudos de Coortes , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Fatores de Risco
5.
Rev Cardiovasc Med ; 20(4): 263-266, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31912717

RESUMO

Renal congestion is becoming recognized as a potential contributor to cardiorenal syndromes. Adequate control of congestion with simultaneous preservation of renal function has been proposed as a central goal of the management of heart failure. We report our care of a 48-year-old woman suffering from right heart failure and massive fluid overload due to severe pulmonary hypertension secondary to a combination of left-heart disease and status after recurrent pulmonary embolisms. Alterations in Doppler-derived intrarenal venous flow patterns and a novel renal venous stasis index were used to evaluate improvement in renal venous congestion during recompensation. Due to refractory congestion despite optimal medical treatment and continuous veno-venous hemodialysis, a peritoneal dialysis catheter was placed to relieve the massive ascites. The paracentesis of ascites led to a significant loss of weight, normalization of hydration status with subsequent termination of continuous veno-venous hemodialysis, and a significant improvement in clinical and echocardiographic parameters. Renal Doppler ultrasonography showed continuous improvement in intrarenal venous flow patterns and the renal venous stasis index indicative of effective decongestion up to a normal intrarenal venous flow pattern and renal venous stasis index. Furthermore, residual renal function increased during follow-up. This case demonstrates the feasibility of renal Doppler ultrasonography as a simple, non-invasive, and integrative measure of renal congestion. The renal venous stasis index and intrarenal venous flow patterns may be useful to evaluate the treatment response and to guide therapy in patients with right heart failure.


Assuntos
Síndrome Cardiorrenal/terapia , Insuficiência Cardíaca/terapia , Hipertensão Pulmonar/terapia , Veias Renais/diagnóstico por imagem , Ultrassonografia Doppler , Disfunção Ventricular Direita/terapia , Função Ventricular Direita , Equilíbrio Hidroeletrolítico , Desequilíbrio Hidroeletrolítico/terapia , Velocidade do Fluxo Sanguíneo , Síndrome Cardiorrenal/diagnóstico por imagem , Síndrome Cardiorrenal/etiologia , Síndrome Cardiorrenal/fisiopatologia , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/fisiopatologia , Pessoa de Meia-Idade , Circulação Renal , Veias Renais/fisiopatologia , Resultado do Tratamento , Disfunção Ventricular Direita/diagnóstico por imagem , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia , Desequilíbrio Hidroeletrolítico/diagnóstico , Desequilíbrio Hidroeletrolítico/etiologia , Desequilíbrio Hidroeletrolítico/fisiopatologia
6.
Nephrol Dial Transplant ; 34(2): 308-317, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30053231

RESUMO

Background: Cardiac surgery is a leading cause of acute kidney injury (AKI). Such AKI patients may develop progressive chronic kidney disease (CKD). Others, who appear to have sustained no permanent loss of function (normal serum creatinine), may still lose renal functional reserve (RFR). Methods: We extended the follow-up in the observational 'Preoperative RFR Predicts Risk of AKI after Cardiac Surgery' study from hospital discharge to 3 months after surgery for 86 (78.2%) patients with normal baseline estimated glomerular filtration rate (eGFR), and re-measured RFR with a high oral protein load. The primary study endpoint was change in RFR. Study registration at clinicaltrials.gov Identifier: NCT03092947, ISRCTN Registry: ISRCTN16109759. Results: At 3 months, three patients developed new CKD. All remaining patients continued to have a normal eGFR (93.3 ± 15.1 mL/min/1.73 m2). However, when stratified by post-operative AKI and cell cycle arrest (CCA) biomarkers, AKI patients displayed a significant decrease in RFR {from 14.4 [interquartile range (IQR) 9.5 - 24.3] to 9.1 (IQR 7.1 - 12.5) mL/min/1.73 m2; P < 0.001} and patients without AKI but with positive post-operative CCA biomarkers also experienced a similar decrease of RFR [from 26.7 (IQR 22.9 - 31.5) to 19.7 (IQR 15.8 - 22.8) mL/min/1.73 m2; P < 0.001]. In contrast, patients with neither clinical AKI nor positive biomarkers had no such decrease of RFR. Finally, of the three patients who developed new CKD, two sustained AKI and one had positive CCA biomarkers but without AKI. Conclusions: Among elective cardiac surgery patients, AKI or elevated post-operative CCA biomarkers were associated with decreased RFR at 3 months despite normalization of serum creatinine. Larger prospective studies to validate the use of RFR to assess renal recovery in combination with biochemical biomarkers are warranted.


Assuntos
Injúria Renal Aguda/etiologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Cardiopatias/complicações , Cardiopatias/cirurgia , Insuficiência Renal Crônica/etiologia , Biomarcadores/sangue , Creatinina/sangue , Feminino , Seguimentos , Taxa de Filtração Glomerular , Humanos , Rim/fisiopatologia , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Período Pós-Operatório , Estudos Prospectivos
7.
Plant J ; 90(3): 491-504, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28181322

RESUMO

A major factor determining aluminium (Al) sensitivity in higher plants is the binding of Al to root cell walls. The Al binding capacity of cell walls is closely linked to the extent of pectin methylesterification, as the presence of methyl groups attached to the pectin backbone reduces the net negative charge of this polymer and hence limits Al binding. Despite recent progress in understanding the molecular basis of Al resistance in a wide range of plants, it is not well understood how the methylation status of pectin is mediated in response to Al stress. Here we show in Arabidopsis that mutants lacking the gene LEUNIG_HOMOLOG (LUH), a member of the Groucho-like family of transcriptional co-repressor, are less sensitive to Al-mediated repression of root growth. This phenotype is correlated with increased levels of methylated pectin in the cell walls of luh roots as well as altered expression of cell wall-related genes. Among the LUH-repressed genes, PECTIN METHYLESTERASE46 (PME46) was identified as reducing Al binding to cell walls and hence alleviating Al-induced root growth inhibition by decreasing PME enzyme activity. seuss-like2 (slk2) mutants responded to Al in a similar way as luh mutants suggesting that a LUH-SLK2 complex represses the expression of PME46. The data are integrated into a model in which it is proposed that PME46 is a major inhibitor of pectin methylesterase activity within root cell walls.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Parede Celular/metabolismo , Proteínas Correpressoras/metabolismo , Pectinas/metabolismo , Raízes de Plantas/metabolismo , Proteínas Repressoras/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Hidrolases de Éster Carboxílico/genética , Proteínas Correpressoras/genética , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Plantas Geneticamente Modificadas , Proteínas Repressoras/genética
8.
Plant Cell ; 26(7): 2889-904, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25052716

RESUMO

The transition zone (TZ) of the root apex is the perception site of Al toxicity. Here, we show that exposure of Arabidopsis thaliana roots to Al induces a localized enhancement of auxin signaling in the root-apex TZ that is dependent on TAA1, which encodes a Trp aminotransferase and regulates auxin biosynthesis. TAA1 is specifically upregulated in the root-apex TZ in response to Al treatment, thus mediating local auxin biosynthesis and inhibition of root growth. The TAA1-regulated local auxin biosynthesis in the root-apex TZ in response to Al stress is dependent on ethylene, as revealed by manipulating ethylene homeostasis via the precursor of ethylene biosynthesis 1-aminocyclopropane-1-carboxylic acid, the inhibitor of ethylene biosynthesis aminoethoxyvinylglycine, or mutant analysis. In response to Al stress, ethylene signaling locally upregulates TAA1 expression and thus auxin responses in the TZ and results in auxin-regulated root growth inhibition through a number of auxin response factors (ARFs). In particular, ARF10 and ARF16 are important in the regulation of cell wall modification-related genes. Our study suggests a mechanism underlying how environmental cues affect root growth plasticity through influencing local auxin biosynthesis and signaling.


Assuntos
Alumínio/toxicidade , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Transdução de Sinais , Triptofano Transaminase/genética , Aminoácidos Cíclicos/metabolismo , Arabidopsis/citologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/metabolismo , Transporte Biológico , Parede Celular/metabolismo , Etilenos/metabolismo , Genes Reporter , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Triptofano Transaminase/metabolismo , Regulação para Cima
10.
Ann Bot ; 118(1): 1-9, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27106549

RESUMO

BACKGROUND AND AIMS: Aluminium (Al) toxicity and drought are two major limiting factors for common bean (Phaseolus vulgaris) production on tropical acid soils. Polyethylene glycol (PEG 6000)-induced osmotic stress (OS) simulating drought stress reduces Al accumulation in the entire root tips of common bean by alteration of cell-wall (CW) porosity, which might be regulated by two genes encoding xyloglucan endotransglucosylase/hydrolase, PvXTH9 and PvXTHb The aim of this research was to understand the spatial and temporal regulation of both XTH genes in PEG-mediated Al accumulation in the root tips. METHODS: In this study the spatial and temporal expression patterns of Al-inhibited root elongation, Al accumulation, XTH gene expression and xyloglucan endotransglucosylase (XET) enzyme action in the root tips were analysed under PEG-induced OS by a combination of physiological and molecular approaches such as quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and in situ fluorescence detection of XET in root tips. KEY RESULTS: The results showed that Al accumulation, expression of XTH genes and XET action were distinctly reduced in the apical 0-2, 2-7 and 7-12 mm zones under OS, implying a potential regulatory role of XTH genes and XET enzyme in CW Al accumulation in these zones. CONCLUSIONS: The results provide novel insights into the physiological and molecular mechanisms of CW structure modification as a response of plant roots to OS, which will contribute to mitigate Al and drought stresses, severely limiting crop yields on acid soils.


Assuntos
Alumínio/metabolismo , Glicosiltransferases/metabolismo , Phaseolus/metabolismo , Raízes de Plantas/metabolismo , Polietilenoglicóis/farmacologia , Alumínio/farmacocinética , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Glicosiltransferases/genética , Phaseolus/efeitos dos fármacos , Phaseolus/genética , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Análise Espaço-Temporal
11.
Ann Bot ; 118(4): 593-605, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27255099

RESUMO

Background Plants depend on their root systems to acquire the water and nutrients necessary for their survival in nature, and for their yield and nutritional quality in agriculture. Root systems are complex and a variety of root phenes have been identified as contributors to adaptation to soils with low fertility and aluminium (Al) toxicity. Phenotypic characterization of root adaptations to infertile soils is enabling plant breeders to develop improved cultivars that not only yield more, but also contribute to yield stability and nutritional security in the face of climate variability. Scope In this review the adaptive responses of root systems to soils with low fertility and Al toxicity are described. After a brief introduction, the purpose and focus of the review are outlined. This is followed by a description of the adaptive responses of roots to low supply of mineral nutrients [with an emphasis on low availability of nitrogen (N) and phosphorus (P) and on toxic levels of Al]. We describe progress in developing germplasm adapted to soils with low fertility or Al toxicity using selected examples from ongoing breeding programmes on food (maize, common bean) and forage/feed (Brachiaria spp.) crops. A number of root architectural, morphological, anatomical and metabolic phenes contribute to the superior performance and yield on soils with low fertility and Al toxicity. Major advances have been made in identifying root phenes in improving adaptation to low N (maize), low P (common bean) or high Al [maize, common bean, species and hybrids of brachiariagrass, bulbous canarygrass (Phalaris aquatica) and lucerne (Medicago sativa)]. Conclusions Advanced root phenotyping tools will allow dissection of root responses into specific root phenes that will aid both conventional and molecular breeders to develop superior cultivars. These new cultivars will play a key role in sustainable intensification of crop-livestock systems, particularly in smallholder systems of the tropics. Development of these new cultivars adapted to soils with low fertility and Al toxicity is needed to improve global food and nutritional security and environmental sustainability.

12.
Blood Purif ; 42(3): 214-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27522219

RESUMO

There is increasing evidence that deleterious interactions between the lung and the kidney may be partly responsible for the multiorgan failure and high mortality seen in patients with acute respiratory distress syndrome. Lung protective strategies can reduce many of the adverse mechanistic and biological effects of mechanical ventilation. However, the key modifiable mediators are yet to be defined for the titration of balance between protective ventilation settings and distant organ function. Disparate but complementary mechanisms that may be involved in acute lung-kidney interactions will be discussed. A kidney-lung protective strategy in patients on mechanical ventilation is a potential approach that should be exploited to improve outcomes in critically ill patients. Video Journal Club 'Cappuccino with Claudio Ronco' at http://www.karger.com/?doi=448471.


Assuntos
Respiração Artificial , Síndrome do Desconforto Respiratório , Estado Terminal , Humanos , Rim , Pulmão
13.
J Exp Bot ; 66(13): 3669-81, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25944925

RESUMO

Nitrogen (N) efficiency of winter oilseed rape (Brassica napus L.) line-cultivars (cvs.), defined as high grain yield under N limitation, has been primarily attributed to maintained N uptake during reproductive growth (N uptake efficiency) in combination with delayed senescence of the older leaves accompanied with maintained photosynthetic capacity (functional stay-green). However, it is not clear whether genotypic variation in N starvation-induced leaf senescence is due to leaf-inherent factors and/or governed by root-mediated signals. Therefore, the N-efficient and stay-green cvs. NPZ-1 and Apex were reciprocally grafted with the N-inefficient and early-senescing cvs. NPZ-2 and Capitol, respectively and grown in hydroponics. The senescence status of older leaves after 12 days of N starvation assessed by SPAD, photosynthesis and the expression of the senescence-specific cysteine protease gene SAG12-1 revealed that the stay-green phenotype of the cvs. NPZ-1 and Apex under N starvation was primarily under the control of leaf-inherent factors. The same four cultivars were submitted to N starvation for up to 12 days in a time-course experiment. The specific leaf contents of biologically active and inactive cytokinins (CKs) and the expression of genes involved in CK homeostasis revealed that under N starvation leaves of early-senescing cultivars were characterized by inactivation of biologically active CKs, whereas in stay-green cultivars synthesis, activation, binding of and response to biologically active CKs were favoured. These results suggest that the homeostasis of biologically active CKs was the predominant leaf-inherent factor for cultivar differences in N starvation-induced leaf senescence and thus N efficiency.


Assuntos
Brassica napus/metabolismo , Nitrogênio/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Estações do Ano , Brassica napus/genética , Clorofila/metabolismo , Citocininas/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Glucosídeos/metabolismo , Homeostase , Peptídeo Hidrolases/metabolismo , Fotossíntese , Folhas de Planta/enzimologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transdução de Sinais/genética , Zeatina/metabolismo
15.
Physiol Plant ; 153(2): 253-68, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24930426

RESUMO

Verticillium dahliae is a prominent generator of plant vascular wilting disease and sulfur (S)-enhanced defense (SED) mechanisms contribute to its in-planta elimination. The accumulation of S-containing defense compounds (SDCs) including elemental S (S(0) ) has been described based on the comparison of two near-isogenic tomato (Solanum lycopersicum) lines differing in fungal susceptibility. To better understand the effect of S nutrition on V. dahliae resistance both lines were supplied with low, optimal or supraoptimal sulfate-S. An absolute quantification demonstrated a most effective fungal elimination due to luxury plant S nutrition. High-pressure liquid chromatography (HPLC) showed a strong regulation of Cys levels and an S-responsive GSH pool rise in the bulk hypocotyl. High-frequency S peak accumulations were detected in vascular bundles of resistant tomato plants after fungal colonization by laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Global transcriptomic analysis suggested that early steps of the primary S metabolism did not promote the SDCs synthesis in the whole hypocotyl as gene expression was downregulated after infection. Enhanced S fertilization mostly alleviated the repressive fungal effect but did not reverse it. Upregulation of glutathione (GSH)-associated genes in bulk hypocotyls but not in vascular bundles indicated a global antioxidative role of GSH. To finally assign the contribution of S metabolism-associated genes to high S(0) accumulations exclusively found in the resistant tomato line, a spatial gene expression approach was applied. Laser microdissection of infected vascular bundles revealed a switch toward transcription of genes connected with cysteine (Cys) synthesis. The upregulation of LeOASTLp1 suggests a role for Cys as key precursor for local S accumulations (possibly S(0) ) in the vascular bundles of the V. dahliae-resistant tomato line.


Assuntos
Cisteína/metabolismo , Regulação da Expressão Gênica de Plantas , Hipocótilo/genética , Feixe Vascular de Plantas/metabolismo , Solanum lycopersicum/genética , Solanum lycopersicum/microbiologia , Enxofre/metabolismo , Verticillium/fisiologia , Transporte Biológico/efeitos dos fármacos , Contagem de Colônia Microbiana , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Estudos de Associação Genética , Genótipo , Hipocótilo/efeitos dos fármacos , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/imunologia , Microdissecção , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Feixe Vascular de Plantas/efeitos dos fármacos , Feixe Vascular de Plantas/genética , Feixe Vascular de Plantas/microbiologia , Espectrofotometria Atômica , Sulfatos/farmacologia , Compostos de Sulfidrila/metabolismo , Verticillium/efeitos dos fármacos , Verticillium/crescimento & desenvolvimento , Xilema/microbiologia
16.
Ann Hepatol ; 14(6): 929-32, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26436367

RESUMO

Pulmonary hypertension is a common finding in patients with advanced liver disease. Similarly, among patients with advanced pulmonary arterial hypertension, right heart failure leads to congestive hepatopathy. Diuretic resistant fluid overload in both advanced pulmonary hypertension and chronic liver disease is a demanding challenge for physicians. Venous congestion and ascites-induced increased intra-abdominal pressure are essential regarding recurrent hospitalization, morbidity and mortality. Due to impaired right-ventricular function, many patients cannot tolerate extracorporeal ultrafiltration. Peritoneal dialysis, a well-established, hemodynamically tolerated treatment for outpatients may be a good alternative to control fluid status. We present a patient with pulmonary arterial hypertension and congestive hepatopathy hospitalized for over 3 months due to ascites induced refractory volume overload treated with peritoneal ultrafiltration. We report the treatment benefits on fluid balance, cardiorenal and pulmonary function, as well as its safety. In conclusion, we report a case in which peritoneal ultrafiltration was an efficient treatment option for refractory ascites in patients with congestive hepatopathy.


Assuntos
Ascite/terapia , Hipertensão Pulmonar/complicações , Diálise Peritoneal , Equilíbrio Hidroeletrolítico , Ascite/diagnóstico , Ascite/etiologia , Ascite/fisiopatologia , Feminino , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/fisiopatologia , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
17.
J Sci Food Agric ; 94(10): 2064-72, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24323937

RESUMO

BACKGROUND: Wines rich in biogenic amines can cause adverse health effects to the consumer. Being nitrogen-containing substances, the amount of amines in wines might be strongly influenced by the rate of nitrogen fertiliser application during grape production. The aim of this work was to evaluate the effect of nitrogen fertilisation in the vineyard on the formation of biogenic amines in musts and wines. RESULTS: In a field experiment which compared unfertilised and fertilised (60 and 150 kg N ha(-1)) vines over two separate years, the total amine concentrations in must and wine increased. The latter was due to an increase of individual amines such as ethylamine, histamine, isopentylamine, phenylethylamine and spermidine in the musts and wines with the nitrogen application. Furthermore, the fermentation process increased the concentration of histamine and ethylamine in most of the treatments, while spermidine, spermine and isopentylamine concentrations generally decreased. Throughout both vintages, the concentrations of tyramine and histamine of the investigated musts and wines never reached detrimental levels to the health of non-allergenic people. CONCLUSIONS: Nitrogen fertilisation has a significant effect on amines formation in musts and wines. Furthermore, during fermentation, ethylamine and histamine increased while other amines were presumably serving as N sources during fermentation.


Assuntos
Aminas Biogênicas/análise , Fermentação , Fertilizantes , Frutas/metabolismo , Nitrogênio/metabolismo , Vitis/metabolismo , Vinho/análise , Humanos
18.
ESC Heart Fail ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467465

RESUMO

Congestive nephropathy is an underappreciated manifestation of cardiorenal syndrome and is characterized by a potentially reversible kidney dysfunction caused by a reduced renal venous outflow secondary to right-sided heart failure or intra-abdominal hypertension. To date, the histological diagnostic criteria for congestive nephropathy have not been defined. We herein report a case of acute renal dysfunction following cardiac allograft failure and present a review of the relevant literature to elucidate the current understanding of the disease. Our case demonstrated that congestion-driven nephropathy may be histopathologically characterized by markedly dilated veins and peritubular capillaries, focally accentuated low-grade acute tubular damage, small areas of interstitial fibrosis, and tubular atrophy on a background of normal glomeruli and predominantly normal tubular cell differentiation.

19.
J Exp Bot ; 64(18): 5569-86, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24123251

RESUMO

Previous studies have shown that polyethylene glycol (PEG)-induced osmotic stress (OS) reduces cell-wall (CW) porosity and limits aluminium (Al) uptake by root tips of common bean (Phaseolus vulgaris L.). A subsequent transcriptomic study suggested that genes related to CW processes are involved in adjustment to OS. In this study, a proteomic and phosphoproteomic approach was applied to identify OS-induced protein regulation to further improve our understanding of how OS affects Al accumulation. Analysis of total soluble proteins in root tips indicated that, in total, 22 proteins were differentially regulated by OS; these proteins were functionally categorized. Seventy-seven per- cent of the total expressed proteins were involved in metabolic pathways, particularly of carbohydrate and amino acid metabolism. An analysis of the apoplastic proteome revealed that OS reduced the level of five proteins and increased that of seven proteins. Investigation of the total soluble phosphoproteome suggested that dehydrin responded to OS with an enhanced phosphorylation state without a change in abundance. A cellular immunolocalization analysis indicated that dehydrin was localized mainly in the CW. This suggests that dehydrin may play a major protective role in the OS-induced physical breakdown of the CW structure and thus maintenance of the reversibility of CW extensibility during recovery from OS. The proteomic and phosphoproteomic analyses provided novel insights into the complex mechanisms of OS-induced reduction of Al accumulation in the root tips of common bean and highlight a key role for modification of CW structure.


Assuntos
Pressão Osmótica , Phaseolus/fisiologia , Fosfoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Aminoácidos/metabolismo , Metabolismo dos Carboidratos , Parede Celular/metabolismo , Eletroforese em Gel Bidimensional , Phaseolus/efeitos dos fármacos , Fosfoproteínas/análise , Proteínas de Plantas/análise , Raízes de Plantas/metabolismo , Polietilenoglicóis/farmacologia , Proteômica/métodos
20.
J Am Heart Assoc ; 12(16): e030145, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37577933

RESUMO

Background The impact of changes in Doppler-derived kidney venous flow in heart failure (HF) is not well studied. We aimed to investigate the association of Doppler-derived kidney venous stasis index (KVSI) and intrakidney venous-flow (IKVF) patterns with adverse cardiorenal outcomes in patients with HF. Methods and Results In this observational cohort study, consecutive inpatients with HF referred to a nephrologist because of a history of diuretic resistance and abnormal kidney function (n=216) underwent spectral kidney assessments after admission (Doppler 1) and 25 to 35 days later (Doppler 2) to identify IKVF patterns (continuous/pulsatile/biphasic/monophasic) and KVSI levels. Cox proportional hazard regression models were used to evaluate the associations between KVSI/IKVF patterns at Doppler 1 as well as changes from Doppler 1 to Doppler 2 and risk of cardiorenal events up to 18 months after admission. Worsening HF or death occurred in 126 patients. Both baseline KVSI (hazard ratio [HR], 1.49 [95% CI, 1.37-1.61] per 0.1-unit increase) and baseline IKVF pattern (HR, 2.47 [95% CI, 2.01-3.04] per 1 pattern severity increase) were significantly associated with worsening HF/death. Increases in both KVSI and IKVF pattern severity from Doppler 1 to 2 were also associated with an increased risk of worsening HF/death (HR, 3.00 [95% CI, 2.08-4.32] per 0.1-unit increase change; and HR, 6.73 [95% CI, 3.27-13.86] per 1 pattern increase in severity change, respectively). Similar results were observed for kidney outcomes. Conclusions Baseline kidney venous flow predicted adverse cardiorenal events, and inclusion of serial kidney venous flow in cardiorenal risk stratification could facilitate clinical decision-making for patients with HF. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03039959.


Assuntos
Insuficiência Cardíaca , Doenças Vasculares , Humanos , Rim , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico por imagem
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