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1.
Neuropediatrics ; 54(5): 351-355, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36603837

RESUMO

OBJECTIVE: By loading transfer RNAs with their cognate amino acids, aminoacyl-tRNA synthetases (ARS) are essential for protein translation. Both cytosolic ARS1-deficiencies and mitochondrial ARS2 deficiencies can cause severe diseases. Amino acid supplementation has shown to positively influence the clinical course of four individuals with cytosolic ARS1 deficiencies. We hypothesize that this intervention could also benefit individuals with mitochondrial ARS2 deficiencies. METHODS: This study was designed as a N-of-1 trial. Daily oral L-phenylalanine supplementation was used in a 3-year-old girl with FARS2 deficiency. A period without supplementation was implemented to discriminate the effects of treatment from age-related developments and continuing physiotherapy. Treatment effects were measured through a physiotherapeutic testing battery, including movement assessment battery for children, dynamic gait index, gross motor function measure 66, and quality of life questionnaires. RESULTS: The individual showed clear improvement in all areas tested, especially in gross motor skills, movement abilities, and postural stability. In the period without supplementation, she lost newly acquired motor skills but regained these upon restarting supplementation. No adverse effects and good tolerance of treatment were observed. INTERPRETATION AND CONCLUSION: Our positive results encourage further studies both on L-phenylalanine for other individuals with FARS2 deficiency and the exploration of this treatment rationale for other ARS2 deficiencies. Additionally, treatment costs were relatively low at 1.10 €/day.


Assuntos
Fenilalanina-tRNA Ligase , Criança , Feminino , Humanos , Pré-Escolar , Fenilalanina-tRNA Ligase/genética , Fenilalanina-tRNA Ligase/química , Fenilalanina-tRNA Ligase/metabolismo , Fenilalanina/metabolismo , Qualidade de Vida , Mitocôndrias/genética , Mitocôndrias/metabolismo , RNA de Transferência/metabolismo , Proteínas Mitocondriais/genética
2.
Curr Pharm Des ; 27(34): 3602-3608, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33430747

RESUMO

Non-small cell lung cancer is usually diagnosed at the advanced stage of the disease. We have novel diagnostic tools. However, prevention is still the best way to deal with this disease. Patients receive different treatments with different adverse effects. Targeted treatment with tyrosine kinase inhibitors and immunotherapy have entered everyday clinical practice. The nutritional status of a patient plays a crucial role in the treatment of the patient. Cachexia is observed in most cancer patients, and it has been identified as an independent factor in the overall survival of the patient. The improvement of nutritional status and metabolism directly impacts the quality of life, daily living, and overall survival of a lung cancer patient. We conducted a search on PubMed and Scopus and identified relevant publications. In this review, we will focus on the nutritional status of NSCLC patients and how food supplements assist in the QoL based on published literature. Additional information from other cancer types will be included where necessary.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Suplementos Nutricionais , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Estado Nutricional , Qualidade de Vida
3.
Plant Cell Physiol ; 60(7): 1401-1404, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31076754

RESUMO

The19th edition of the International Symposium on Iron Nutrition and Interactions in Plants, a biannual meeting initiated in 1981, took place in Taiwan for the first time. The five-day event was held at the Academia Sinica campus in the Southeast of Taiwan's capital city Taipei, and hosted around 200 scientists from around the world. The meeting covered a diverse array of topics centered around iron nutrition, including but not limited to soil processes, biofortification, transport, signaling and molecular processes regulating the cellular homeostasis of iron. Here, I review the research foci highlighted during the meeting by oral and poster presentations.


Assuntos
Ferro/metabolismo , Plantas/metabolismo , Biofortificação , Congressos como Assunto
4.
Plant Physiol ; 177(1): 194-207, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29559590

RESUMO

Iron (Fe) is an essential mineral nutrient and an important factor for the composition of natural plant communities. Low Fe availability in aerated soils with neutral or alkaline pH has led to the evolution of elaborate mechanisms that extract Fe from the soil solution. In Arabidopsis (Arabidopsis thaliana), Fe is acquired by an orchestrated strategy that comprises mobilization, chelation, and reduction of Fe3+ prior to its uptake. Here, we show that At3g12900, previously annotated as scopoletin 8-hydroxylase (S8H), participates in Fe acquisition by mediating the biosynthesis of fraxetin (7,8-dihydroxy-6-methoxycoumarin), a coumarin derived from the scopoletin pathway. S8H is highly induced in roots of Fe-deficient plants both at the transcript and protein levels. Mutants defective in the expression of S8H showed increased sensitivity to growth on pH 7.0 media supplemented with an immobile source of Fe and reduced secretion of fraxetin. Transgenic lines overexpressing S8H exhibited an opposite phenotype. Homozygous s8h mutants grown on media with immobilized Fe accumulated significantly more scopolin, the storage form of scopoletin, supporting the designated function of S8H in scopoletin hydroxylation. Fraxetin exhibited Fe-reducing properties in vitro with higher rates being observed at neutral relative to acidic pH. Supplementing the media containing immobile Fe with fraxetin partially rescued the s8h mutants. In natural Arabidopsis accessions differing in their performance on media containing immobilized Fe, the amount of secreted fraxetin was highly correlated with growth and Fe and chlorophyll content, indicating that fraxetin secretion is a decisive factor for calcicole-calcifuge behavior (i.e. the ability/inability to thrive on alkaline soils) of plants.


Assuntos
Arabidopsis/metabolismo , Cumarínicos/metabolismo , Ferro/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Disponibilidade Biológica , Cumarínicos/farmacologia , Regulação da Expressão Gênica de Plantas , Concentração de Íons de Hidrogênio , Hidroxilação , Ferro/farmacocinética , Mutação , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Escopoletina/metabolismo
5.
J Exp Bot ; 68(18): 5021-5027, 2017 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-29036459

RESUMO

The biological significance of iron (Fe) is based on its propensity to oscillate between the ferric and ferrous forms, a transition that also affects its phyto-availability in soils. With the exception of grasses, Fe3+ is unavailable to plants. Most angiosperms employ a reduction-based Fe uptake mechanism, which relies on enzymatic reduction of ferric iron as an obligatory, rate-limiting step prior to uptake. This system functions optimally in acidic soils. Calcicole plants are, however, exposed to environments that are alkaline and/or have suboptimal availability of phosphorous, conditions under which the enzymatic reduction mechanism ceases to work effectively. We propose that auxiliary, non-enzymatic Fe reduction can be of critical importance for conferring fitness to plants thriving in alkaline soils with low bioavailability of Fe and/or phosphorus.


Assuntos
Concentração de Íons de Hidrogênio , Ferro/metabolismo , Fósforo/metabolismo , Raízes de Plantas/metabolismo , Plantas/metabolismo , Solo/química , Magnoliopsida/metabolismo , Oxirredução
6.
Rofo ; 189(9): 828-843, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28511267

RESUMO

Background Image-guided thermal ablation can be used for the treatment of medically inoperable primary and metastatic lung cancer. These techniques are based on the heating up or freezing (cryoablation) of a volume of tissue around a percutaneous applicator that induces necrosis of the tumor. Method The English-language literature concerning thermal ablation of the lung was reviewed. Radiofrequency ablation (RFA) is the most widely performed and investigated of these techniques. Microwave ablation (MWA) represents a relatively new alternative that shares the same indications and is conducted in a very similar fashion as RFA. It has been experimentally and clinically shown that MWA produces larger, more spherical ablation zones over shorter periods of time compared to RFA. Seven different MWA systems are available in Europe and the USA with significant differences in the size and shape of the produced ablation zones. Results The types of complications caused by MWA and their rates of occurrence are very similar to those caused by RFA. The local progression rates after MWA of lung malignancies vary between 0 % and 34 % and are similar to those in the RFA literature. Conclusion Despite technical improvements, the current generation of MWA systems has comparable clinical outcomes to those of RFA. Key Points · MWA is a safe technique that should be considered one of the treatment options for medically inoperable lung tumors. · As thermal ablations of lung tumors are becoming more frequent, radiologists should be acquainted with the post-ablation imaging characteristics. · Although MWA has some theoretical advantages over RFA, the clinical outcomes are similar. Citation Format · Vogl TJ, Nour-Eldin NA, Albrecht MH et al. Thermal Ablation of Lung Tumors: Focus on Microwave Ablation. Fortschr Röntgenstr 2017; 189: 828 - 843.


Assuntos
Técnicas de Ablação/métodos , Hipertermia Induzida , Neoplasias Pulmonares/cirurgia , Micro-Ondas/uso terapêutico , Medicina Baseada em Evidências , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Cirurgia Assistida por Computador , Resultado do Tratamento
7.
Ann Rheum Dis ; 74(10): 1799-807, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26359488

RESUMO

Therapy for polymyalgia rheumatica (PMR) varies widely in clinical practice as international recommendations for PMR treatment are not currently available. In this paper, we report the 2015 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) recommendations for the management of PMR. We used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology as a framework for the project. Accordingly, the direction and strength of the recommendations are based on the quality of evidence, the balance between desirable and undesirable effects, patients' and clinicians' values and preferences, and resource use. Eight overarching principles and nine specific recommendations were developed covering several aspects of PMR, including basic and follow-up investigations of patients under treatment, risk factor assessment, medical access for patients and specialist referral, treatment strategies such as initial glucocorticoid (GC) doses and subsequent tapering regimens, use of intramuscular GCs and disease modifying anti-rheumatic drugs (DMARDs), as well as the roles of non-steroidal anti-rheumatic drugs and non-pharmacological interventions. These recommendations will inform primary, secondary and tertiary care physicians about an international consensus on the management of PMR. These recommendations should serve to inform clinicians about best practices in the care of patients with PMR.


Assuntos
Polimialgia Reumática/tratamento farmacológico , Algoritmos , Antirreumáticos/uso terapêutico , Pesquisa Biomédica/métodos , Gerenciamento Clínico , Esquema de Medicação , Medicina Baseada em Evidências/métodos , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Humanos , Cooperação Internacional , Fitoterapia/métodos , Polimialgia Reumática/diagnóstico
8.
J Cancer ; 6(6): 568-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26000049

RESUMO

Historical, the non-small cell lung cancer (NSCLC) was as a united disease entity and the chemotherapy to the metastatic cancer had limited results. Recent studies for the metastatic non-small cell lung cancer led to the ascertainment that the NSCLC does not constitute exclusively a disease entity, but different neoplasms guided from different molecular paths, different biological behavior and at extension requires different confrontation. Thus the new direction for the therapeutic approach of NSCLC is henceforth the most individualized approach based on the activated molecular paths of tumor. Distinct subtypes of NSCLC are driven by a specific genetic alteration, like EGFR, ALK, ROS1 or BRAF mutations, and these genetic alterations are sensitized to the inhibition of specific oncogenic pathways. The benefit from the use of tyrosine kinase inhibitors in patients with EGFR mutations it was confirmed by six randomized studies of phase III that investigated the role of gefitinib, erlotinib and afatinib. In these studies the response rates vary in the impressive percentages from 55% to 86% and were connected with a remarkable median progression free survival of approximately 8 to 13 months, and with better quality of life compared to that of chemotherapy. In early stages NSCLC is needed the individualization of systemic treatment in order to reduce toxicity that is observed in the classic chemotherapy and to impact outcome. The role of EGFR TKI's has been evaluated in the adjuvant chemotherapy in early stage resected NSCLC. The data from these studies suggest that adjuvant TKI therapy might not increase the overall survival, but delay the recurrences. Prospective trials restricted to EGFR or ALK driven NSCLC subsets potentially offering the opportunity for a definitive answer in early disease adjuvant setting (ALCHEMIST) or as induction treatment before stage III chemo-radiotherapy (RTOG 1210/Alliance 31101), are ongoing. Ongoing prospective trials may offer the opportunity for a definitive answer of the role of tyrosine kinase inhibitors in induction treatment before chemo-radiotherapy or in early disease adjuvant therapy.

9.
Drug Des Devel Ther ; 7: 1003-13, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24082782

RESUMO

Humans have the ability to synthesize vitamin D during the action of ultraviolet (UV) radiation upon the skin. Apart from the regulation of calcium and phosphate metabolism, another critical role for vitamin D in immunity and respiratory health has been revealed, since vitamin D receptors have also been found in other body cells. The term "vitamin D insufficiency" has been used to describe low levels of serum 25-hydroxyvitamin D that may be associated with a wide range of pulmonary diseases, including viral and bacterial respiratory infection, asthma, chronic obstructive pulmonary disease, and cancer. This review focuses on the controversial relationship between vitamin D and asthma. Also, it has been found that different gene polymorphisms of the vitamin D receptor have variable associations with asthma. Other studies investigated the vitamin D receptor signaling pathway in vitro or in experimental animal models and showed either a beneficial or a negative effect of vitamin D in asthma. Furthermore, a range of epidemiological studies has also suggested that vitamin D insufficiency is associated with low lung function. In the future, clinical trials in different asthmatic groups, such as infants, children of school age, and ethnic minorities are needed to establish the role of vitamin D supplementation to prevent and/or treat asthma.


Assuntos
Asma/fisiopatologia , Receptores de Calcitriol/metabolismo , Vitamina D/metabolismo , Animais , Asma/tratamento farmacológico , Asma/etiologia , Criança , Suplementos Nutricionais , Humanos , Lactente , Polimorfismo Genético , Receptores de Calcitriol/genética , Transdução de Sinais , Vitamina D/administração & dosagem , Deficiência de Vitamina D/complicações
10.
J Complement Integr Med ; 10(Suppl): S39-46, S41-9, 2013.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-24021606

RESUMO

As part of a placebo-controlled study, high-resolution measurement methods were used to examine, on the basis of representative functional characteristics of microcirculation, whether and to what extent six different, commercially available, physical treatment devices were suitable for influencing, through complementary therapy, deficient blood-flow regulation. Of the six commercially available devices tested, two proved to be ineffective and three not effective enough to be therapeutically relevant. Only in one device was it possible to show a complementary-therapeutic effect: the device uses a specific, biorhythmically defined stimulus for vasomotion.


Assuntos
Arteríolas/fisiopatologia , Terapias Complementares/métodos , Hemodinâmica/fisiologia , Microcirculação/fisiologia , Modalidades de Fisioterapia , Fluxo Sanguíneo Regional , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Periodicidade , Rinite/sangue , Rinite/terapia , Estresse Psicológico/sangue , Estresse Psicológico/terapia
11.
Mol Cell Proteomics ; 11(11): 1156-66, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22843991

RESUMO

Phosphate (Pi) deficiency impairs plant growth and productivity in many agricultural ecosystems, causing severe reductions in crop yield. To uncover novel aspects in acclimation to Pi starvation, we investigated the correlation between Pi deficiency-induced changes in transcriptome and proteome profiles in Arabidopsis roots. Using exhaustive tandem mass spectrometry-based shotgun proteomics and whole-genome RNA sequencing to generate a nearly complete catalog of expressed mRNAs and proteins, we reliably identified 13,298 proteins and 24,591 transcripts, subsets of 356 proteins and 3106 mRNAs were differentially expressed during Pi deficiency. Most dramatic changes were noticed for genes involved in Pi acquisition and in processes that either liberate Pi or bypass Pi/ATP-consuming metabolic steps, for example during membrane lipid remodeling and glycolytic carbon flux. The concordance between the abundance of mRNA and its encoded protein was generally high for highly up-regulated genes, but the analysis also revealed numerous discordant changes in mRNA/protein pairs, indicative of divergent regulation of transcription and post-transcriptional processes. In particular, a decreased abundance of proteins upon Pi deficiency was not closely correlated with changes in the corresponding mRNAs. In several cases, up-regulation of gene activity was observed solely at the protein level, adding novel aspects to key processes in the adaptation to Pi deficiency. We conclude that integrated measurement and interpretation of changes in protein and transcript abundance are mandatory for generating a complete inventory of the components that are critical in the response to environmental stimuli.


Assuntos
Arabidopsis/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Fosfatos/deficiência , Raízes de Plantas/metabolismo , Proteoma/metabolismo , Proteômica , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Carbono/metabolismo , Genes de Plantas/genética , Glucose/metabolismo , Homeostase/genética , Marcação por Isótopo , Bicamadas Lipídicas/metabolismo , Modelos Biológicos , Raízes de Plantas/genética , Mapas de Interação de Proteínas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
12.
Plant Physiol ; 155(2): 821-34, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21173025

RESUMO

Iron (Fe) deficiency is a major constraint for plant growth and affects the quality of edible plant parts. To investigate the mechanisms underlying Fe homeostasis in plants, Fe deficiency-induced changes in the protein profile of Arabidopsis (Arabidopsis thaliana) roots were comprehensively analyzed using iTRAQ (Isobaric Tag for Relative and Absolute Quantification) differential liquid chromatography-tandem mass spectrometry on a LTQ-Orbitrap with high-energy collision dissociation. A total of 4,454 proteins were identified with a false discovery rate of less than 1.1%, and 2,882 were reliably quantified. A subset of 101 proteins was differentially expressed upon Fe deficiency. The changes in protein profiles upon Fe deficiency show low congruency with previously reported alterations in transcript levels, indicating posttranscriptional changes, and provide complementary information on Fe deficiency-induced processes. The abundance of proteins involved in the synthesis/regeneration of S-adenosylmethionine, the phenylpropanoid pathway, the response to oxidative stress, and respiration was highly increased by Fe deficiency. Using Fe-responsive proteins as bait, genome-wide fishing for partners with predictable or confirmed interologs revealed that RNA processing and ribonucleoprotein complex assembly may represent critical processes that contribute to the regulation of root responses to Fe deficiency, possibly by biasing translation efficiency.


Assuntos
Arabidopsis/metabolismo , Homeostase , Ferro/metabolismo , Raízes de Plantas/metabolismo , Proteoma/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Análise por Conglomerados , Regulação da Expressão Gênica de Plantas , Deficiências de Ferro , Raízes de Plantas/fisiologia , Processamento Pós-Transcricional do RNA , Espectrometria de Massas em Tandem
13.
Onkologie ; 33(11): 617-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20975309

RESUMO

BACKGROUND: The clinical prognosis of metastatic pancreatic cancer is very poor, with a median survival time of such patients ranging from 3 to 6 months. Current chemotherapy regimens include the combination of oxaliplatin and gemcitabine. CASE REPORT: A 43-year-old woman was diagnosed with pancreatic adenocarcinoma spreading into the regional lymph nodes and into multiple liver segments (pT3, pN1, pM1). Upon diagnosis, she underwent a pylorus-preserving pancreatic head resection, including dissection of regional lymph nodes and atypical resection of a single liver segment, followed by 9 cycles of palliative chemotherapy with gemcitabine and oxaliplatin. 37 weeks after surgery, the patient demonstrated a sustained partial remission, and the chemotherapy was stopped. Surprisingly, 10 months later, she still showed no evidence of tumor progression. Since the time of pancreatic surgery, the patient had taken mistletoe extracts and this adjunctive treatment has been continued until now. CONCLUSIONS: Cases of sustained long-term remission of metastatic pancreatic cancer are extremely rare. Although this single case observation does not allow for firm conclusions regarding potential mechanisms, the adjunctive therapy with mistletoe extracts might have played a role. Therefore, the clinical effects of such treatment in patients with pancreatic cancer warrant further investigation.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/secundário , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Erva-de-Passarinho/química , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/secundário , Extratos Vegetais/uso terapêutico , Adulto , Quimioterapia Adjuvante , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Humanos , Metástase Linfática , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Fitoterapia/métodos , Resultado do Tratamento , Gencitabina
14.
Regul Pept ; 160(1-3): 75-80, 2010 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-19695292

RESUMO

INTRODUCTION: Amino acids are important modulators of glucose metabolism, insulin secretion and insulin sensitivity. However, little is known about the changes in amino acid metabolism in patients with diabetes. PATIENTS AND METHODS: The circulating amino acid levels were determined in 17 patients with type 2 diabetes, 17 individuals with impaired glucose tolerance (IGT), and 14 control subjects. RESULTS: Total amino acid concentrations were 2850+/-57micromol/l in patients with type 2 diabetes, 2980+/-77micromol/l in individuals with IGT, and 2886+/-74micromol/l in control subjects (p=0.38). Patients with type 2 diabetes exhibited significant reductions in the concentrations of gamma-aminobutyric acid (GABA), arginine, glutamine and phosphoethanolamine (p<0.05), whereas valine levels were higher than in controls (p=0.008). In IGT subjects, GABA levels were reduced, while tyrosine concentrations were increased (p<0.05). The plasma levels of essential amino acids were positively related to fasting and post-challenge glucose levels, fasting C-peptide, HOMA insulin resistance and fasting glucagon levels (p<0.05). CONCLUSIONS: Total amino acid levels are similar in patients with diabetes, IGT subjects and controls, but the individual levels of several amino acids differ significantly between these groups. These alterations may contribute to the disturbances in insulin secretion and action in diabetic patients and may provide a rationale for offering specific amino acid supplementations to diabetic patients.


Assuntos
Aminoácidos/deficiência , Diabetes Mellitus Tipo 2 , Intolerância à Glucose , Aminoácidos/sangue , Aminoácidos/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Intolerância à Glucose/sangue , Intolerância à Glucose/complicações , Intolerância à Glucose/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Referência
15.
Pancreas ; 38(4): 416-21, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19169171

RESUMO

OBJECTIVES: Chronic pancreatitis (CP) and pancreatic cancer (CA) have been associated with intestinal malabsorption and inflammation. However, little is known about the changes in amino acid metabolism in such patients. METHODS: The circulating amino acid levels were determined in 12 patients with CP, 12 CA patients, and 12 controls. RESULTS: Total amino acid concentrations were 2850 +/- 71 micromol/L in controls, 2640 +/- 96 micromol/L in CP patients, and 2210 +/- 123 micromol/L in CA patients (P < 0.001). In CP patients, significant reductions in the concentrations of citrulline, gamma-aminobutyric acid, taurine, and aspartic acid were found (P < 0.05), whereas in CA patients, the levels of phosphoethanolamine, gamma-aminobutyric acid, aspartic acid, taurine, arginine, threonine, alanine, citrulline, and tryptophan were reduced. There was a significant inverse relationship between the total amino acid levels and the white blood cell counts (r = -0.44, P = 0.008). CONCLUSIONS: Both patients with CP and with CA exhibit alterations in amino acid levels. The mechanisms underlying these defects may involve intestinal malabsorption as well as systemic inflammation. Providing selective amino acid supplementation to such patients may minimize the excess morbidity and mortality associated with protein malnutrition.


Assuntos
Aminoácidos/sangue , Neoplasias Pancreáticas/sangue , Pancreatite Crônica/sangue , Aminoácidos Essenciais/sangue , Análise de Variância , Glicemia/análise , Cromatografia Líquida de Alta Pressão , Jejum/sangue , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Desnutrição/sangue , Pessoa de Meia-Idade
16.
AIDS ; 20(11): 1554-6, 2006 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-16847412

RESUMO

Supplementation with uridine offers the possibility of a new and promising approach to nucleoside analogue reverse transcriptase inhibitor-associated mitochondrial toxicity. We investigated the metabolic effects of short-course treatment with the uridine-enriched food supplement NucleomaxX on hepatic mitochondrial function in thymidine-analogue treated HIV-infected patients. Mitochondrial function was assessed by a recently introduced non-invasive C-methionine breath test. NucleomaxX supplementation enhanced mitochondrial decarboxylation function reversibly but reproducibly in all patients. Repeated administration in shorter treatment intervals may maintain this effect.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Suplementos Nutricionais , Síndrome de Lipodistrofia Associada ao HIV/tratamento farmacológico , Mitocôndrias Hepáticas/efeitos dos fármacos , Uridina/uso terapêutico , Testes Respiratórios/métodos , Síndrome de Lipodistrofia Associada ao HIV/fisiopatologia , Humanos , Masculino , Mitocôndrias Hepáticas/fisiologia , Inibidores da Transcriptase Reversa/efeitos adversos
17.
Bioorg Med Chem Lett ; 15(16): 3679-84, 2005 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15982873

RESUMO

The metabolic stability of benzoxazinone derivatives, a potent series of NPY Y5 antagonists, has been investigated. This study resulted in the identification of the structural moieties prone to metabolic transformations and which strongly influenced the in vitro half-life. This provides opportunities to optimize the structure of this new class of NPY Y5 antagonists.


Assuntos
Oxazinas/metabolismo , Oxazinas/farmacologia , Receptores de Neuropeptídeo Y/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos , Estabilidade de Medicamentos , Estrutura Molecular , Oxazinas/química , Receptores de Neuropeptídeo Y/metabolismo , Relação Estrutura-Atividade
18.
Plant Physiol ; 134(1): 409-19, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14730071

RESUMO

Postembryonic development of plants is dependent on both intrinsic genetic programs and environmental factors. The plasticity of root hair patterning in response to environmental signals was investigated in the Columbia-0 wild type and 19 Arabidopsis mutants carrying lesions in various parts of the root hair developmental pathway by withholding phosphate or iron (Fe) from the nutrient medium. In the aging primary root and in laterals of the wild type, the number of root hairs increased in response to phosphate and Fe deficiency in a manner typical of each growth type. Although an increase in root hair density in -phosphorus plants was mainly achieved by the formation of extra hairs over both tangential and radial wall of underlying cortical cells, roots of -Fe plants were characterized by a high percentage of extra hairs with two tips. Root hair patterning and hair length was differentially affected by the presence or absence of phosphate and Fe among the genotypes under investigation, pointing to separate cascades of gene activation under all three growth conditions. Divergence in root hair patterning was most pronounced among mutants with defects in genes that affect the first stages of differentiation, suggesting that nutritional signals are perceived at an early stage of epidermal cell development. During elongation of the root hairs, no differences in the requirement of gene products between the growth types were obvious. The role of genes involved in root hair development in the aging primary root of Arabidopsis under the various growth conditions is discussed.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Arabidopsis/metabolismo , Meio Ambiente , Ferro/metabolismo , Modelos Biológicos , Mutação , Fenótipo , Fósforo/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento
19.
Planta ; 215(2): 304-11, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12029480

RESUMO

In roots of tomato ( Lycopersicon esculentum Mill.), extranumerary root hairs and transfer cell-like wall ingrowth depositions in the rhizodermis were developed in response to P and Fe deficiency. Immunocytolocalization of the plasma membrane H(+)-ATPase in roots of P-deficient plants revealed no appreciable increase in H(+)-ATPase density relative to control plants. In transfer cells, immunogold labeling was considerably higher than in ordinary rhizodermal cells. H(+)-ATPase sites were asymmetrically distributed in cells with and without wall ingrowths under P-deficient conditions. A split-root study revealed that the frequency of transfer cells was higher in the low-P half of the root system, but the density of H(+)-ATPase molecules was enhanced only in the high-P half of the split roots, suggesting that formation of transfer cells was controlled directly by the external Pi concentration, whereas ATPase expression was regulated indirectly by the internal nutrient status of the plant. The role of hormones in the induction of transfer cells was investigated by treating plants with the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) or various ethylene antagonists. Transfer cells were induced by ACC to an extent similar to that observed after P or Fe starvation, but inhibitors of either ethylene synthesis or action did not decrease their frequency. These results suggest that ethylene was not required for the induction of transfer cells but changes in ethylene levels appeared to modulate the number of cells forming wall ingrowths. In roots of ethylene-insensitive Never-ripe tomato plants the frequency of transfer cells was rather increased than decreased under most growth conditions relative to the wild type, indicating that ethylene responsiveness played no critical role in the differentiation of transfer cells and that the transduction of signals ultimately leading to their formation was independent of the ethylene signaling cascade.


Assuntos
Deficiências de Ferro , Fósforo/deficiência , ATPases Translocadoras de Prótons/metabolismo , Solanum lycopersicum/enzimologia , Aminoácidos Cíclicos/farmacologia , Comunicação Celular/fisiologia , Diferenciação Celular/fisiologia , Membrana Celular/metabolismo , Etilenos/antagonistas & inibidores , Etilenos/farmacologia , Ferro/farmacologia , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/genética , Microscopia Imunoeletrônica , Mutação , Fósforo/farmacologia , Epiderme Vegetal/citologia , Epiderme Vegetal/enzimologia , Epiderme Vegetal/ultraestrutura , Raízes de Plantas/citologia , Raízes de Plantas/enzimologia , Raízes de Plantas/ultraestrutura , Transdução de Sinais/fisiologia
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