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1.
Pituitary ; 25(6): 982-987, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36260240

RESUMO

Central Diabetes Insipidus (CDI) is mainly associated with structural pathologies of the hypothalamic-pituitary area. Etiologies underlying CDI are identified in most patients, however idiopathic CDI is reported in 13-17% of cases after excluding other etiologies. The Hypopituitarism ENEA Rare Observational Study (HEROS study) retrospectively collected data of patients with idiopathic CDI from 14 pituitary centers in 9 countries. The cohort included 92 patients (59 females 64%), mean age at diagnosis was 35.4 ± 20.7 years, and a mean follow up of 19.1 ± 13.5 years following CDI diagnosis. In 6 women, diagnosis was related to pregnancy. Of 83 patients with available data on pituitary imaging, 40(48%) had normal sellar imaging, and 43(52%) had pathology of the posterior pituitary or the stalk, including loss of the bright spot, posterior pituitary atrophy or stalk enlargement. Anterior pituitary hormone deficiencies at presentation included hypogonadism in 6 (6.5%) patients (5 females), and hypocortisolism in one; during follow-up new anterior pituitary deficiencies developed in 6 patients. Replacement treatment with desmopressin was given to all patients except one, usually with an oral preparation. During follow up, no underlying disease causing CDI was identified in any patient. Patients with idiopathic CDI following investigation at baseline are stable with no specific etiology depicted during long-term follow-up.


Assuntos
Diabetes Insípido Neurogênico , Diabetes Insípido , Diabetes Mellitus , Hipopituitarismo , Doenças da Hipófise , Humanos , Feminino , Diabetes Insípido Neurogênico/tratamento farmacológico , Diabetes Insípido Neurogênico/diagnóstico , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Diabetes Insípido/etiologia , Hipopituitarismo/complicações , Doenças da Hipófise/complicações , Hipófise/patologia
2.
J Endocrinol Invest ; 41(3): 315-323, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28815484

RESUMO

BACKGROUND: Late-night salivary cortisol level is one of the first-line tests recommended by the Endocrine Society for the diagnosis of endogenous hypercortisolism. Most routine laboratories measure cortisol levels using immunoassay tests which fail to determine low cortisol levels accurately due to the numerous interfering substances. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method with simple and rapid sample preparation was developed for the simultaneous measurement of cortisol and cortisone and its performance in the diagnosis of endogenous hypercortisolism was evaluated. METHODS: 324 late-night saliva samples were analyzed from which 272 samples were derived from patients with a suspected diagnosis of endogenous hypercortisolism. Salivary cortisol levels were assayed using an electrochemiluminescent immunoassay (ECLIA, Cortisol II, Roche), and simultaneous measurement of cortisol and cortisone was performed using an LC-MS/MS method. RESULTS: A strong correlation between cortisol results measured using ECLIA and LC-MS/MS (r 2 = 0.892) was demonstrated. Receiver operating characteristics (ROC) analysis showed good diagnostic performance of cortisol and cortisone levels assayed using LC-MS/MS method and for cortisol measured using ECLIA. CONCLUSIONS: Late-night salivary cortisol and cortisone are useful parameters for the diagnosis of hypercortisolism. Using samples obtained from patients where the diagnosis of hypercortisolism is extremely challenging cut-off values for midnight salivary cortisol and cortisone measured by LC-MS/MS method were established.


Assuntos
Bioensaio , Cromatografia Líquida/métodos , Cortisona/metabolismo , Síndrome de Cushing/diagnóstico , Hidrocortisona/metabolismo , Saliva/metabolismo , Espectrometria de Massas em Tandem/métodos , Biomarcadores/metabolismo , Estudos de Casos e Controles , Síndrome de Cushing/metabolismo , Humanos , Prognóstico , Curva ROC
3.
Sci Total Environ ; 946: 174191, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945249

RESUMO

East-Central Europe's largest shallow lake, Balaton, experienced strong eutrophication in the 1970-80s, followed by water quality improvement and oligotrophication by 2010 CE. Recently however, repeated cyanobacterial blooms occurred and warned that internal P-recycling can act similarly to external P load, therefore we need a better understanding of past water level (WL) and trophic changes in the lake. In this study we discuss the last 500-yr trophic, WL and habitat changes of the lake using paleoecological (chironomids, pollen) and geochemical (sediment chlorophyll, TOC, TS, TN, C/H ratio, major and trace element) methods. We demonstrate that the most intensive and irreversible change in the macroinvertebrate fauna occurred during the period of economic boom between the First and Second World War (∼1925-1940 CE), when large-scale built-in and leisure use of the lake has intensified. At that time, the Procladius-Microchironomus-Stempellina dominated community transformed to Procladius-Chironomus plumosus-type-Microchironomus community that coincided with land use changes, intensified erosion and water-level regulation in the lake with the maintenance of year-round high WL. This was followed by the impoverishment and population size decrease of the chironomid fauna and Procladius dominance since 1940 CE, without any recovery after 1994 CE despite the ongoing oligotrophication. Accelerated rate of change and turnover of the fauna was connected to an increase in the benthivorous fish biomass and eutrophication. The basin lost almost completely its once characteristic Stempellina species between 1927 and 1940 CE due to trophic level increase and seasonal anoxia in the Szemes Basin. Reference conditions for ecosystem improvement were assigned to 1740-1900 CE. We conclude that in spite of the ongoing oligotrophication, the re-establishment of the Procladius-Microchironomus-Stempellina assemblage is hampered, and requires fish population regulation.

4.
Mol Psychiatry ; 17(6): 612-23, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21808255

RESUMO

Depression is a major health problem worldwide. Most prescribed anti-depressants, the selective serotonin reuptake inhibitors (SSRI) show limited efficacy and delayed onset of action, partly due to the activation of somatodendritic 5-HT(1A)-autoreceptors by the excess extracellular serotonin (5-HT) produced by SSRI in the raphe nuclei. Likewise, 5-HT(1A) receptor (5-HT(1A)R) gene polymorphisms leading to high 5-HT(1A)-autoreceptor expression increase depression susceptibility and decrease treatment response. In this study, we report on a new treatment strategy based on the administration of small-interfering RNA (siRNA) to acutely suppress 5-HT(1A)-autoreceptor-mediated negative feedback mechanisms. We developed a conjugated siRNA (C-1A-siRNA) by covalently binding siRNA targeting 5-HT(1A) receptor mRNA with the SSRI sertraline in order to concentrate it in serotonin axons, rich in serotonin transporter (SERT) sites. The intracerebroventricular (i.c.v.) infusion of C-1A-siRNA to mice resulted in its selective accumulation in serotonin neurons. This evoked marked anti-depressant-like effects in the forced swim and tail suspension tests, but did not affect anxiety-like behaviors in the elevated plus-maze. In parallel, C-1A-siRNA administration markedly decreased 5-HT(1A)-autoreceptor expression and suppressed 8-OH-DPAT-induced hypothermia (a pre-synaptic 5-HT(1A)R effect in mice) without affecting post-synaptic 5-HT(1A)R expression in hippocampus and prefrontal cortex. Moreover, i.c.v. C-1A-siRNA infusion augmented the increase in extracellular serotonin evoked by fluoxetine in prefrontal cortex to the level seen in 5-HT(1A)R knockout mice. Interestingly, intranasal C-1A-siRNA administration produced the same effects, thus opening the way to the therapeutic use of C-1A-siRNA. Hence, C-1A-siRNA represents a new approach to treat mood disorders as monotherapy or in combination with SSRI.


Assuntos
Antidepressivos/uso terapêutico , Autorreceptores/antagonistas & inibidores , Depressão/tratamento farmacológico , Combinação de Medicamentos , RNA Interferente Pequeno/uso terapêutico , Receptor 5-HT1A de Serotonina/genética , 8-Hidroxi-2-(di-n-propilamino)tetralina/antagonistas & inibidores , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Administração Intranasal , Animais , Autorreceptores/biossíntese , Modelos Animais de Doenças , Desenho de Fármacos , Fluoxetina/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipotermia/induzido quimicamente , Hipotermia/tratamento farmacológico , Infusões Intraventriculares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Receptor 5-HT1A de Serotonina/biossíntese , Receptor 5-HT1A de Serotonina/química , Neurônios Serotoninérgicos/efeitos dos fármacos , Neurônios Serotoninérgicos/metabolismo , Sertralina/administração & dosagem , Sertralina/química
5.
Nanotechnology ; 24(3): 035301, 2013 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-23263276

RESUMO

Direct-write three-dimensional nanolithography is demonstrated using cryogenic electron beam-induced deposition (EBID). Cryogenic cooling and an electron beam were used to condense and expose the precursor methylcyclopentadienyl(trimethyl)platinum (MeCpPtMe(3)). The exposure process was modeled by Monte Carlo simulations of electron-condensate interactions, which were used to develop two approaches for the fabrication of three-dimensional self-supporting structures with incorporated gaps. Vertical and lateral resolutions of approximately 150 and 22 nm are demonstrated, and underlying mechanisms that limit resolution and throughput are identified. Resolution can be traded off for condensate exposure efficiency, which is shown to be up to four orders of magnitude greater than that of conventional, room temperature EBID.

6.
Bioorg Med Chem ; 21(21): 6634-41, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24012376

RESUMO

The objective of this study was to synthesize and evaluate a novel fluorine-18 labeled deuterium substituted analogue of rasagiline (9, [(18)F]fluororasagiline-D2) as a potential PET radioligand for studies of monoamine oxidase B (MAO-B). The precursor compound (6) and reference standard (7) were synthesized in multi-step syntheses. Radiolabeling of 9 was accomplished by a two-step synthesis, compromising a nucleophilic substitution followed by hydrolysis of the sulfamidate group. The incorporation radiochemical yield from fluorine-18 fluoride was higher than 30%, the radiochemical purity was >99% and the specific radioactivity was >160GBq/µmol at the time of administration. In vitro compound 7 inhibited the MAO-B activity with an IC50 of 173.0±13.6nM. The MAO-A activity was inhibited with an IC50 of 9.9±1.1µM. The fluorine-18 version 9 was characterized in the cynomolgus monkey brain where a high brain uptake was found (275% SUV at 4min). There was a higher uptake in the striatum and thalamus compared to the cortex and cerebellum. A pronounced blocking effect (50% decrease) was observed in the specific brain regions after administration of l-deprenyl (0.5mg/kg) 30min prior to the administration of 9. Radiometabolite studies demonstrated 40% of unchanged radioligand at 90min post injection. An efficient radiolabeling of 9 was successfully established and in the monkey brain 9 binds to MAO-B rich regions and its binding is blocked by the selective MAO-B compound l-deprenyl. The radioligand 9 is a potential candidate for human PET studies.


Assuntos
Indanos/química , Inibidores da Monoaminoxidase/química , Monoaminoxidase/química , Compostos Radiofarmacêuticos/química , Animais , Encéfalo/diagnóstico por imagem , Córtex Cerebral/metabolismo , Deutério/química , Radioisótopos de Flúor/química , Humanos , Indanos/metabolismo , Macaca fascicularis/metabolismo , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/metabolismo , Tomografia por Emissão de Pósitrons , Ligação Proteica , Compostos Radiofarmacêuticos/metabolismo , Tálamo/metabolismo
7.
Proc Natl Acad Sci U S A ; 107(16): 7592-7, 2010 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-20368423

RESUMO

Low serotonin(1A) receptor (5-HT(1A)R) binding is a risk factor for anxiety and depression, and deletion of the 5-HT(1A)R results in anxiety-like behavior in mice. Here we show that anxiety-like behavior in mice also can be caused, independently of the offspring's own 5-HT(1A)R genotype, by a receptor deficit in the mother: a nongenetic transmission of a genetic defect. Some of the nongenetically transmitted anxiety manifestations were acquired prenatally and linked to a delay in dentate gyrus maturation in the ventral hippocampus of the offspring. Both the developmental delay and the anxiety-like phenotype were phenocopied by the genetic inactivation of p16(ink4a) encoding a cyclin-dependent kinase inhibitor implicated in neuronal precursor differentiation. No maternal 5-HT(1A)R genotype-dependent anxiety developed when the strain background was switched from Swiss Webster to C57BL/6, consistent with the increased resilience of this strain to early adverse environment. Instead, all anxiety manifestations were caused by the offspring's own receptor deficiency, indicating that the genetic and nongenetic effects converge to common anxiety manifestations. We propose that 5-HT(1A)R deficit represents a dual risk for anxiety and that vulnerability to anxiety associated with genetic 5-HT(1A)R deficiency can be transmitted by both genetic and nongenetic mechanisms in a population. Thus, the overall effect of risk alleles can be higher than estimated by traditional genetic assays and may contribute to the relatively high heritability of anxiety and psychiatric disorders in general.


Assuntos
Ansiedade/genética , Prenhez , Receptor 5-HT1A de Serotonina/genética , Receptor 5-HT1A de Serotonina/fisiologia , Animais , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Giro Denteado/metabolismo , Feminino , Genótipo , Exposição Materna , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Fenótipo , Gravidez , Risco
8.
Nat Genet ; 11(1): 71-5, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7550318

RESUMO

Epidemiological data and genetic studies indicate that certain forms of human epilepsy are inherited. Based on the similarity between the human and mouse genomes, mouse models of epilepsy could facilitate the discovery of genes associated with epilepsy syndromes. Here, we report an insertional murine mutation that inactivates a novel gene and results in whole body jerks, generalized clonic seizures, and epileptic brain activity in transgenic mice. The gene, named jerky, encodes a putative 41.7 kD protein displaying homology to a number of nuclear regulatory proteins, suggesting that perhaps the jerky protein is able to bind DNA.


Assuntos
Proteínas de Ligação a DNA/genética , Epilepsia Tônico-Clônica/genética , Genes , Proteínas do Tecido Nervoso/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Química Encefálica , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/fisiologia , Modelos Animais de Doenças , Epilepsia Tônico-Clônica/fisiopatologia , Manobra Psicológica , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Mutantes Neurológicos , Camundongos Transgênicos , Dados de Sequência Molecular , Mutagênese Insercional , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/fisiologia , Linhagem , Proteínas de Ligação a RNA
9.
Nat Genet ; 17(2): 206-10, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9326944

RESUMO

MAOA and MAOB are key iso-enzymes that degrade biogenic and dietary amines. MAOA preferentially oxidizes serotonin (5-hydroxytryptamine, or 5-HT) and norepinephrine (NE), whereas MAOB preferentially oxidizes beta-phenylethylamine (PEA). Both forms can oxidize dopamine (DA). A mutation in MAOA results in a clinical phenotype characterized by borderline mental retardation and impaired impulse control. X-chromosomal deletions which include MAOB were found in patients suffering from atypical Norrie's disease, which is characterized by blindness and impaired hearing. Reduced MAOB activity has been found in type-II alcoholism and in cigarette smokers. Because most alcoholics smoke, the effects of alcohol on MAOB activity remain to be determined. Here we show that targetted inactivation of MAOB in mice increases levels of PEA but not those of 5-HT, NE and DA, demonstrating a primary role for MAOB in the metabolism of PEA. PEA has been implicated in modulating mood and affect. Indeed, MAOB-deficient mice showed an increased reactivity to stress. In addition, mutant mice were resistant to the neurodegenerative effects of MPTP, a toxin that induces a condition reminiscent of Parkinson's disease.


Assuntos
Monoaminoxidase/deficiência , Fenetilaminas/metabolismo , Estresse Fisiológico/enzimologia , Animais , Sequência de Bases , Monoaminas Biogênicas/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Primers do DNA/genética , Feminino , Humanos , Intoxicação por MPTP , Masculino , Camundongos , Camundongos Knockout , Monoaminoxidase/genética , Atividade Motora/genética , Atividade Motora/fisiologia , Oxirredução , Reação em Cadeia da Polimerase , Mapeamento por Restrição , Estresse Fisiológico/genética , Estresse Fisiológico/fisiopatologia , Cromossomo X/genética
10.
Rozhl Chir ; 92(12): 715-21, 2013 Dec.
Artigo em Tcheco | MEDLINE | ID: mdl-24479517

RESUMO

INTRODUCTION: Endovascular abdominal aortic aneurysm repair (EVAR) is a modern and, compared to conventional open surgery, less invasive therapeutic strategy with short-term lower morbidity and mortality. The aim of our retrospective analysis was the assessment of safety, technical success, short-term and mid-term results of elective patients scheduled for total percutaneous EVAR implantation (PEVAR). MATERIAL AND METHODS: One hundred and sixteen consecutive patients (M:F 104:12, age 71±9 years, maximum AAA diameter 60±14mm) underwent elective PEVAR between January 2009 and August 2012. All the patients were treated under local anaesthesia by total percutaneous approach via femoral access. The immediate technical success of stentgraft implantation as well as the presence of 30-day and 1-year complications and the need of reintervention rate were assessed. RESULTS: In 115/116 patients (99.1%),immediate technical success of the procedure was recorded, with no need of conversion to open surgery; in 1 patient (0.9%) the performance technically failed due to unfavourable arterial anatomy. The mortality in 30-day follow-up was 2.6% (3 patients), during 1-year follow-up it amounted to 8.6% (10 patients), without causal relationship with stentgraft implantation. Overall event-free survival was 85% (98/116) without serious complications (mortality, MI, stroke, reintervention, severe ischemic complication) in the one-year follow-up period. CONCLUSION: Endovascular AAA repair is a safe and feasible method with low mortality and acceptable complication rate in patients scheduled for EVAR implantation. Percutaneous approach allows for the extension of indications also for the highest-risk group of polymorbid patients. Technical feasibility and adequate periprocedural management are essential for further reduction in adverse events after PEVAR.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Endovasculares/métodos , Complicações Pós-Operatórias/etiologia , Stents , Idoso , Aneurisma da Aorta Abdominal/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
11.
Semin Arthritis Rheum ; 63: 152285, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37944298

RESUMO

BACKGROUND: Giant Cell Arteritis (GCA) is the commonest form of systemic vasculitis in people over the age of 50. Published research highlighted the lack of a disease-specific patient reported outcomes (PROMs) for GCA. OBJECTIVES: To assess the validity, reliability and responsiveness to change of a devised disease specific patient self-reported outcome measures questionnaire for Giant Cell Arteritis (GCA). METHODS: The GCA-PROMs was conceptualized based on frameworks outlined in the OMERACT developed core set of Outcome Measures for Large-Vessel Vasculitis and the guiding principles of the FDA guidance. Initially, cognitive interviews were conducted to identify item pool of questions. Item selection and reduction was achieved based on patients as well as an interdisciplinary group of specialists. Rasch and internal consistency reliability analyses were implemented. RESULTS: A total of 54 GCA patients completed the questionnaire. The GCA-PROMs questionnaire was reliable as demonstrated by a high standardized alpha (0.878-0.983). Content construct assessment of the GCA-PROMs functional disability and QoL revealed significant correlation (p< 0.01) with both HAQ and EQ-5D. Changes in functional disability, QoL showed significant (p< 0.01) variation with diseases activity status in response to therapy. CONCLUSIONS: The developed GCA-PROMs questionnaire is a reliable and valid instrument for assessment of GCA patients. A stratified treatment regimen depending on the individual patient's risk factors as well as preferences and associated comorbidities is the best approach to tailored patient management.


Assuntos
Arterite de Células Gigantes , Humanos , Qualidade de Vida , Reprodutibilidade dos Testes , Medidas de Resultados Relatados pelo Paciente , Avaliação de Resultados em Cuidados de Saúde
12.
Osteoporos Int ; 21(4): 637-45, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19513576

RESUMO

UNLABELLED: We investigated bone turnover and its restoration in a large number of patients in the active phase and after cure of endogenous Cushing's syndrome. Furthermore, the usefulness of serum osteocalcin and collagen breakdown products as potential markers of active Cushing's syndrome was also evaluated. INTRODUCTION: Suppressed bone formation is one of the most characteristic features of Cushing's syndrome (CS). Despite numerous previous reports, many aspects of the disturbed bone metabolism of these patients are unexplored. In this study, we investigated the time course of bone marker changes after the cure of CS as well as correlations between bone markers and serum cortisol concentrations. METHODS: Eighty-seven patients with CS were studied. Patients were followed up to 48 months after surgical cure. Serum osteocalcin (OC) and collagen breakdown products (CTX) were measured with immunochemiluminescence method and compared to the results of 161 healthy controls. RESULTS: OC showed a negative, while CTX displayed a positive correlation with serum cortisol. Patients with diabetes mellitus and myopathy had significantly lower serum OC levels compared to those without these complications. The area under the curve of OC obtained by receiver-operating characteristics analysis for the discrimination of patients with CS from healthy controls was 0.9227. Postoperative OC increased rapidly from the first few days or weeks reaching its maximum at the sixth month and remained stable after the 24th postoperative month. CONCLUSIONS: Our study demonstrated significant correlations between serum cortisol and both bone formation and resorption markers in the active phase of CS. We propose that OC may serve as a sensitive biologic marker of glucocorticoid activity in endogenous CS during its active phase and it may reflect the clinical cure of the disease.


Assuntos
Remodelação Óssea/fisiologia , Síndrome de Cushing/fisiopatologia , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , Colágeno Tipo I/sangue , Síndrome de Cushing/sangue , Síndrome de Cushing/cirurgia , Feminino , Seguimentos , Humanos , Hidrocortisona/sangue , Masculino , Pessoa de Meia-Idade , Osteocalcina/sangue , Peptídeos/sangue , Período Pós-Operatório , Resultado do Tratamento , Adulto Jovem
13.
Acta Anaesthesiol Scand ; 54(4): 502-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19919584

RESUMO

BACKGROUND: NT-proXNP, a new natriuretic peptide analyte, incorporates information about the concentrations of both N-terminal pro-atrial and pro-brain natriuretic peptides (NT-proANP, NT-proBNP). We aimed to investigate whether NT-proXNP is a reliable indicator of the cardiac index (CI) and the hemodynamic state in neonates and infants undergoing an open heart surgery. METHODS: We enrolled 26 children under the age of 1 year into this prospective study. All patients underwent an elective cardiac operation with cardiopulmonary bypass (CPB) to achieve complete biventricular repair. Peri-operative hemodynamic parameters were assessed by transpulmonary thermodilution and natriuretic peptide levels were recorded. RESULTS: The NT-proXNP level correlated significantly with the simultaneously measured NT-proANP level (r=0.60, P<0.001), but more strongly with the NT-proBNP level (r=0.89, P<0.001) and the arithmetic sum of both (r=0.88, P<0.001). NT-proXNP had a strong correlation with CI (r=-0.85, P<0.001), the stroke volume index (r=-0.80, P<0.001) and the global ejection fraction (r=-0.67, P<0.009) throughout the post-operative period. Conventionally measured parameters such as heart rate, mean arterial pressure and pulse-pressure product exhibited weaker correlations with CI than NT-proXNP. Among laboratory values, creatinine levels correlated significantly with CI (r=-0.77, P<0.001) and NT-proXNP (r=0.76, P<0.001) during the post-operative period. A post-operative NT-proXNP level of 3079 pmol/l was diagnostic for CI <3 l/min/m(2) with 89% sensitivity and 90% specificity (area under the curve: 0.91 +/- 0.05). CONCLUSION: NT-proXNP is a good marker of cardiac output following pediatric cardiac surgery and might be a useful tool in the recognition of a low output state.


Assuntos
Débito Cardíaco/fisiologia , Procedimentos Cirúrgicos Cardíacos , DNA Helicases/metabolismo , Proteínas Nucleares/metabolismo , Biomarcadores , Creatinina/sangue , Eletrocardiografia , Feminino , Cardiopatias Congênitas/cirurgia , Frequência Cardíaca/fisiologia , Ventrículos do Coração/cirurgia , Hemodinâmica/fisiologia , Humanos , Lactente , Recém-Nascido , Masculino , Período Pós-Operatório , Estudos Prospectivos , Precursores de Proteínas/metabolismo , Volume Sistólico/fisiologia , Termodiluição , Proteína Nuclear Ligada ao X
15.
Gut ; 58(4): 545-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18978175

RESUMO

BACKGROUND AND AIMS: Two common haplotypes of the serine protease inhibitor Kazal type 1 (SPINK1) gene have been shown to increase the risk for chronic pancreatitis. A haplotype comprising the c.101A>G (p.N34S) missense variant and four intronic alterations has been found worldwide, whereas a second haplotype consisting of the c.-215G>A promoter variant and the c.194+2T>C intronic alteration has been observed frequently in Japan. METHODS: In the present study, the functional significance of the intronic variants in the pathogenic SPINK1 haplotypes was examined by utilising minigenes, which harbour individual introns placed in the appropriate context of the full-length SPINK1 cDNA. Cells transfected with the SPINK1 minigenes secrete active trypsin inhibitor, thereby allowing evaluation of mutational effects simultaneously on transcription, splicing, translation and secretion. RESULTS: It was found that the c.194+2T>C intronic alteration abolished SPINK1 expression at the mRNA level, with consequent loss of inhibitor secretion, whereas the p.N34S-associated intronic variants had no detectable functional effect. CONCLUSIONS: Taken together with previous studies, the results indicate that all known variants within the p.N34S-associated haplotype are functionally innocuous, suggesting that an as yet unidentified variant within this haplotype is responsible for the pathogenic effect. The marked negative impact of the c.194+2T>C variant on SPINK1 expression supports the notion that SPINK1 variants increase the risk of chronic pancreatitis by diminishing protective trypsin inhibitor levels.


Assuntos
Proteínas de Transporte/genética , Pancreatite Crônica/genética , Proteínas de Transporte/metabolismo , Células Cultivadas , DNA Complementar/genética , Expressão Gênica , Predisposição Genética para Doença , Haplótipos , Células HeLa , Humanos , Íntrons/genética , Pancreatite Crônica/metabolismo , RNA Mensageiro/genética , Transfecção , Inibidor da Tripsina Pancreática de Kazal
16.
Science ; 246(4934): 1149-52, 1989 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-2686029

RESUMO

The structure of a complex between a peptide inhibitor with the sequence N-acetyl-Thr-Ile-Nle-psi[CH2-NH]-Nle-Gln-Arg.amide (Nle, norleucine) with chemically synthesized HIV-1 (human immunodeficiency virus 1) protease was determined at 2.3 A resolution (R factor of 0.176). Despite the symmetric nature of the unliganded enzyme, the asymmetric inhibitor lies in a single orientation and makes extensive interactions at the interface between the two subunits of the homodimeric protein. Compared with the unliganded enzyme, the protein molecule underwent substantial changes, particularly in an extended region corresponding to the "flaps" (residues 35 to 57 in each chain), where backbone movements as large as 7 A are observed.


Assuntos
Endopeptidases/metabolismo , HIV-1/enzimologia , Oligopeptídeos/metabolismo , Inibidores de Proteases/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Fenômenos Químicos , Físico-Química , Cristalização , Produtos do Gene gag/metabolismo , Protease de HIV , Ligação de Hidrogênio , Dados de Sequência Molecular , Estrutura Molecular , Conformação Proteica
17.
Curr Med Chem ; 15(28): 2933-83, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19075645

RESUMO

The protein glycogen phosphorylase has been linked to type 2 diabetes, indicating the importance of this target to human health. Hence, the search for potent and selective inhibitors of this enzyme, which may lead to antihyperglycaemic drugs, has received particular attention. Glycogen phosphorylase is a typical allosteric protein with five different ligand binding sites, thus offering multiple opportunities for modulation of enzyme activity. The present survey is focused on recent new molecules, potential inhibitors of the enzyme. The biological activity can be modified by these molecules through direct binding, allosteric effects or other structural changes. Progress in our understanding of the mechanism of action of these inhibitors has been made by the determination of high-resolution enzyme inhibitor structures (both muscle and liver). The knowledge of the three-dimensional structures of protein-ligand complexes allows analysis of how the ligands interact with the target and has the potential to facilitate structure-based drug design. In this review, the synthesis, structure determination and computational studies of the most recent inhibitors of glycogen phosphorylase at the different binding sites are presented and analyzed.


Assuntos
Química Farmacêutica/métodos , Desenho de Fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Glicogênio Fosforilase/antagonistas & inibidores , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Sítio Alostérico , Animais , Sítios de Ligação , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glicogênio Fosforilase/química , Humanos , Concentração Inibidora 50 , Ligantes , Fígado/enzimologia , Conformação Molecular , Estrutura Terciária de Proteína
18.
Int J Obes (Lond) ; 32(6): 967-74, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18268512

RESUMO

OBJECTIVE: Obesity promotes the development and progression of coronary heart disease (CHD), in part, through its association with hyperlipidemia, hypertension, clotting abnormalities and insulin resistance. We assessed whether these relationships persist in patients with established CHD treated with evidence-based preventive pharmacologic therapies. DESIGN AND SUBJECTS: We performed a cross-sectional study of 74 adults with CHD and a body mass index (BMI) of >27 kg m(-2) (mean 32+/-4). The mean age of subjects was 64+/-9 years (range 44-84 years). MEASUREMENTS: Obesity measures included weight, BMI, waist, fat mass, intra-abdominal fat and subcutaneous fat. Risk factor measures included insulin sensitivity, fasting insulin level, lipid profiles, blood pressure, C-reactive protein (hs-CRP), plasminogen activator inhibitor (PAI-1) and platelet reactivity. Medication use included aspirin (99%), statin (84%), beta-blocker (71%), ACE inhibitor or blocker (37%) and clopidogrel (28%). RESULTS: There was no direct relationship between obesity parameters and risk factor measures of lipid concentrations, blood pressure, clotting abnormalities or platelet reactivity except for a modest relationship between visceral fat and hs-CRP (r=0.30, P=0.02). However, increased BMI, waist circumference, fat mass, total abdominal fat and abdominal subcutaneous fat all correlated with insulin sensitivity (r-values -0.30 to -0.45, P-values 0.01 to <0.001) and insulin concentrations. Insulin sensitivity, in turn, was the best predictor of PAI-1, triglycerides, high-density lipoprotein (HDL) levels, cholesterol/HDL levels (all P<0.01) and platelet reactivity (R=0.34, P=0.02). CONCLUSIONS: Use of preventive pharmacologic therapies obviated the expected relationship between adiposity and CHD risk factors. However, a residual effect of insulin resistance is left untreated. Total adiposity and central adiposity were strong predictors of insulin sensitivity, which in turn predicted cardiac risk factors such as lipid concentrations, PAI-1 and platelet reactivity. Thus, while evidence-based pharmacologic treatments may diminish the statistical relationship between obesity and many cardiac risk factors, adiposity negatively impacts CHD risk by reducing tissue insulin sensitivity.


Assuntos
Doença das Coronárias/etiologia , Resistência à Insulina , Obesidade/complicações , Adiposidade/fisiologia , Antagonistas Adrenérgicos beta/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/metabolismo , Índice de Massa Corporal , Doença das Coronárias/prevenção & controle , Estudos Transversais , Inibidores Enzimáticos/uso terapêutico , Medicina Baseada em Evidências , Feminino , Técnica Clamp de Glucose , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Fatores de Risco
20.
J Endocrinol Invest ; 31(1): 74-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18296909

RESUMO

The authors present the case history of a 52-yr-old male patient with a unique association of combined pituitary hormone deficiency (CPHD) and situs inversus totalis. Except for signs and symptoms of pituitary hormone deficiency, the patient had no dysmorphic features, and hearing impairment, primary mental or neurological defects were also absent. Pituitary magnetic resonance imaging (MRI) scan showed hypoplasia of the anterior lobe of the pituitary gland and an ectopic posterior pituitary lobe. Despite the presence of situs inversus totalis, the patient was right-handed and functional MRI demonstrated left-hemisphere activation during language tests. Kartagener syndrome was considered, but immunofluorescence analysis showed normal localization of the outer dynein arm protein in respiratory epithelial cells obtained from the nasal mucosa. Direct DNA sequencing of all coding exons of the pituitary transcription factor 1 (PIT1) and prophet of PIT1 (PROP1) genes failed to detect disease-causing mutations, suggesting that these genes were not involved in the development of CPHD in our patient. More interestingly, the potential role of the paired like homeodomain transcription factor 2 (PITX2) gene, which has been implicated not only in CPHD, but also in left-right patterning in animal models, was also excluded, as sequencing showed the absence of mutations in coding exons of this gene. To our knowledge, PITX2 gene mutations have not been investigated in CPHD patients who had situs inversus totalis. We conclude that in contrast to animal models, the PITX2 gene is not involved in the development of situs inversus totalis, at least not in our CPHD patient.


Assuntos
Lateralidade Funcional , Hipopituitarismo/complicações , Doenças do Sistema Nervoso/complicações , Hormônios Hipofisários/deficiência , Situs Inversus/complicações , Análise Citogenética , Lateralidade Funcional/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/genética , Situs Inversus/genética
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