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1.
MethodsX ; 9: 101855, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36187157

RESUMO

A general and versatile method for the analysis and processing of HR-TEM data useful for several applications is presented. The first utility is to identify the structures seen in the micrographs; also can be extended to propose the interaction of structure dynamics between various phases; and also it can be hybridized with the chemical method to make a proposal of new structure and/or phase. The general method consisted of four steps: 1) micrograph pretreatment, 2) measurement of planar distances, 3) structure identification, and 4) structure corroboration. Crystallographic planes were immediately identified by comparing the interplanar distances. Next, crystallographic data were collected from the Crystal Structures Database (ICSD) and introduced into Diamond software to visualize the planes in each structure. In addition, from the zone axis point of view it must show the planes aligned, similar as is observed in the HR-TEM micrograph.•It was possible establish the growth mechanism of the different structures by identifying how is the structural interaction between the different oxides and sulfide phases.•Method was successful applied to propose a new TiCoMoS sulfide phase through HR-TEM results.•The method can also be extended to other areas where structural studies with HR-TEM are viable, such as biology, electronics, among others.

2.
Mol Psychiatry ; 26(6): 2277-2285, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32051549

RESUMO

The gene encoding adhesion G protein-coupled receptor L3 (ADGRL3, also referred to as latrophilin 3 or LPHN3) has been associated with ADHD susceptibility in independent ADHD samples. We conducted a systematic review and a comprehensive meta-analysis to summarize the associations between the most studied ADGRL3 polymorphisms (rs6551665, rs1947274, rs1947275, and rs2345039) and both childhood and adulthood ADHD. Eight association studies (seven published and one unpublished) fulfilled criteria for inclusion in our meta-analysis. We also incorporated GWAS data for ADGRL3. In order to avoid overlapping samples, we started with summary statistics from GWAS samples and then added data from gene association studies. The results of our meta-analysis suggest an effect of ADGRL3 variants on ADHD susceptibility in children (n = 8724/14,644 cases/controls and 1893 families): rs6551665 A allele (Z score = -2.701; p = 0.0069); rs1947274 A allele (Z score = -2.033; p = 0.0421); rs1947275 T allele (Z score = 2.339; p = 0.0978); and rs2345039 C allele (Z score = 3.806; p = 0.0026). Heterogeneity was found in analyses for three SNPs (rs6551665, rs1947274, and rs2345039). In adults, results were not significant (n = 6532 cases/15,874 controls): rs6551665 A allele (Z score = 2.005; p = 0.0450); rs1947274 A allele (Z score = 2.179; p = 0.0293); rs1947275 T allele (Z score = -0.822; p = 0.4109); and rs2345039 C allele (Z score = -1.544; p = 0.1226). Heterogeneity was found just for rs6551665. In addition, funnel plots did not suggest publication biases. Consistent with ADGRL3's role in early neurodevelopment, our findings suggest that the gene is predominantly associated with childhood ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/genética , Criança , Estudos de Associação Genética , Predisposição Genética para Doença/genética , Humanos , Polimorfismo de Nucleotídeo Único/genética , Receptores Acoplados a Proteínas G/genética , Receptores de Peptídeos/genética
3.
Materials (Basel) ; 12(23)2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31779127

RESUMO

Technological approaches which enable the effective utilization of CO2 for manufacturing value-added chemicals and fuels can help to solve environmental problems derived from large CO2 emissions associated with the use of fossil fuels. One of the most interesting products that can be synthesized from CO2 is methanol, since it is an industrial commodity used in several chemical products and also an efficient transportation fuel. In this review, we highlight the recent advances in the development of heterogeneous catalysts and processes for the direct hydrogenation of CO2 to methanol. The main efforts focused on the improvement of conventional Cu/ZnO based catalysts and the development of new catalytic systems targeting the specific needs for CO2 to methanol reactions (unfavourable thermodynamics, production of high amount of water and high methanol selectivity under high or full CO2 conversion). Major studies on the development of active and selective catalysts based on thermodynamics, mechanisms, nano-synthesis and catalyst design (active phase, promoters, supports, etc.) are highlighted in this review. Finally, a summary concerning future perspectives on the research and development of efficient heterogeneous catalysts for methanol synthesis from CO2 will be presented.

4.
Data Brief ; 24: 104010, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31193673

RESUMO

The modification of Cu-Zn catalysts with low amount of Al and Ga (Al+Ga = 3%) was investigated and data corresponding to its influence on the decomposition of the calcined precursors and on the nanomorphology and surface concentration of reduced catalysts were presented in this contribution. The data presented here are supplementary material of the catalysts presented in the research article "Structure and activity of Cu/ZnO catalysts co-modified with aluminium and gallium for methanol synthesis" published in Catalysis Today [1].

6.
Allergol Immunopathol (Madr) ; 46(5): 438-446, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29739685

RESUMO

BACKGROUND: Ataxia-telangiectasia (AT) is a well-known primary immunodeficiency with recurrent sinopulmonary infections and variable abnormalities in both the humoral and cellular immune system. Dysfunctions in immunoglobulin production, reduced number of B cells, and B-cell receptor excision circles copies have been reported. We aimed to understand the immunological mechanisms involving the humoral compartment in AT patients by analysing peripheral blood B cells subsets, B-T lymphocyte cooperation through the expression of CD40 and CD40 ligand (CD40L), and cytokines involved in class-switch recombination production. METHODS: We compared the proportion of B-cell subsets, the expression of CD40/CD40L, and the plasma levels of IL-6 and IFN-γ of 18 AT patients and 15 healthy age-sex-matched controls using flow cytometry. RESULTS: We found that some steps in peripheral B cell development were altered in AT with a pronounced reduction of cell-surface CD40 expression. The proportions of transitional and naïve-mature B cells were reduced, whereas CD21-low, natural effector memory, IgM-only memory, and IgG atypical memory B cells were present in a higher proportion. CONCLUSIONS: These findings revealed a disturbed B-cell homeostasis with unconventional maturation of B lymphocyte memory cells, which can explain the consequent impairment of humoral immunity.


Assuntos
Ataxia Telangiectasia/imunologia , Subpopulações de Linfócitos B/imunologia , Adolescente , Adulto , Antígenos CD40/biossíntese , Criança , Pré-Escolar , Feminino , Humanos , Imunofenotipagem , Masculino , Adulto Jovem
7.
Mol Psychiatry ; 23(6): 1446-1452, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28461697

RESUMO

Experimental studies have demonstrated that methylphenidate (MPH) modulates the synaptic vesicle trafficking and synaptotagmin-1 (SytI) mRNA levels. SytI is a regulatory protein of the SNARE complex, a neurotransmitter exocytosis mediator. Despite this evidence, most SNARE complex-related genes have never been evaluated in attention-deficit/hyperactivity disorder (ADHD) pharmacogenetics. This study evaluates, for we believe the first time, polymorphisms on the SNARE complex-related genes STX1A (rs2228607), VAMP2 (26bp Ins/Del) and SYT1 (rs1880867 and rs2251214) on the response to immediate-release methylphenidate (IR-MPH) in a naturalistic sample of adults with ADHD. The sample comprised 433 subjects, of which 272 (62.8%) have completed the short-term IR-MPH treatment (at least 30 days). The main outcome measure was the categorical variable of short-term response to IR-MPH based on the Swanson, Nolan and Pelham Rating Scale version 4 (SNAP-IV), and on the clinical global impression-improvement scale. Additional analyses evaluated the percentage of SNAP-IV symptom reduction for each dimension as well as short- and long- (7 years) term treatment persistence. SYT1-rs2251214 was associated with the categorical short-term response to IR-MPH (P=0.006, PFDR=0.028), and with the percentage of inattention and oppositional defiant disorder symptoms reduction (P=0.007, PFDR=0.028 and P=0.017, PFDR=0.048, respectively). SYT1-rs2251214 was also associated with short-term treatment persistence (P=0.018, PFDR=0.048), and with months of treatment (P=0.002, PFDR=0.016) in the long-term protocol. Our findings suggest that SYT1-rs2251214 presents a broad influence in IR-MPH response variability in adults with ADHD, being involved with both symptom response and treatment persistence. If such findings are replicated, SytI could represent a key element in MPH pharmacodynamics in adults with ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Exocitose/genética , Sinaptotagmina I/genética , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/complicações , Estimulantes do Sistema Nervoso Central , Exocitose/fisiologia , Feminino , Humanos , Masculino , Metilfenidato/farmacologia , Metilfenidato/uso terapêutico , Avaliação de Resultados em Cuidados de Saúde , Polimorfismo Genético , Sinaptotagmina I/metabolismo , Sintaxina 1/genética , Sintaxina 1/metabolismo , Resultado do Tratamento , Proteína 2 Associada à Membrana da Vesícula/genética , Proteína 2 Associada à Membrana da Vesícula/metabolismo
8.
RSC Adv ; 8(37): 20619-20629, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35542371

RESUMO

The influence of aging of precipitates on the physical and catalytic properties of a copper/zinc oxide-aluminium (Cu/ZnO-Al) catalyst with an optimized composition (low Al concentration, Cu/Zn/Al = 68/29/3) prepared using co-precipitation has been investigated in detail. The change in the structure of precipitates with aging (from amorphous zincian georgeite to crystalline zincian malachite) strongly influences the micro- and nano-structure (Cu and ZnO crystallite size, exposed copper surface area, Cu-ZnO interactions and stability of ZnO) of the final Cu/ZnO-Al catalysts obtained after calcination and reduction of the precipitates. The results of catalytic activity in methanol synthesis from syngas show the higher intrinsic activity of the catalysts derived from aged zincian malachite precipitates as consequence of the increase in the exposed copper surface area and the Cu-ZnO contacts. The stability of catalysts under the reaction conditions was also improved in the catalysts derived from precipitates aged after crystallization of malachite. The catalyst derived from the precipitate removed close to the point of crystallization of malachite shows very poor activity in the methanol synthesis as consequence of its segregated large Cu crystallites in low contact with ZnO derived from the absence of carbonate retention after calcination of the precipitate and the presence of sodium species after conventional washing which favour the strong sintering and crystallization of Cu during reduction.

9.
Acta Psychiatr Scand ; 136(2): 210-219, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28555716

RESUMO

OBJECTIVE: There is a lack of available information on the trajectories of attention-deficit/hyperactivity disorder (ADHD) dimensions during adulthood. This study investigates the course and the predictors of change for each ADHD domain in a clinical sample of adults with ADHD. METHOD: Adults with ADHD (n = 344) were followed up for 7 years, with a final retention rate of 66.0%. Trajectories of inattention, hyperactivity, and impulsivity and their potential predictors were examined. RESULTS: On average, symptoms declined in all ADHD domains during follow-up. Despite this, rises in inattentive, hyperactive, and impulsive symptoms were observed in approximately 13%, 25%, and 17% of patients respectively. Different predictors influenced the trajectory of each ADHD dimension. Oppositional defiant disorder and social phobia were associated with the maintenance of symptoms, while alcohol use disorder was associated with both maintenance and rise of symptoms. CONCLUSION: Unexpectedly, a rise in the symptoms after 7 years was not uncommon in adults with ADHD. Prevalent comorbidities have the potential to influence the neurodevelopment and the trajectory of ADHD. Therefore, such predictors should be investigated in population cohorts to better characterize the course of ADHD. Additionally, these findings may be relevant in prevention studies and in strategies for ADHD treatment.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Saúde Mental , Índice de Gravidade de Doença , Adulto , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/fisiopatologia , Comorbidade , Feminino , Seguimentos , Humanos , Masculino
11.
Transl Psychiatry ; 6(10): e923, 2016 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-27754487

RESUMO

Attention-deficit/hyperactivity disorder (ADHD) is a highly heritable childhood-onset neuropsychiatric condition, often persisting into adulthood. The genetic architecture of ADHD, particularly in adults, is largely unknown. We performed an exome-wide scan of adult ADHD using the Illumina Human Exome Bead Chip, which interrogates over 250 000 common and rare variants. Participants were recruited by the International Multicenter persistent ADHD CollaboraTion (IMpACT). Statistical analyses were divided into 3 steps: (1) gene-level analysis of rare variants (minor allele frequency (MAF)<1%); (2) single marker association tests of common variants (MAF⩾1%), with replication of the top signals; and (3) pathway analyses. In total, 9365 individuals (1846 cases and 7519 controls) were examined. Replication of the most associated common variants was attempted in 9847 individuals (2077 cases and 7770 controls) using fixed-effects inverse variance meta-analysis. With a Bonferroni-corrected significance level of 1.82E-06, our analyses of rare coding variants revealed four study-wide significant loci: 6q22.1 locus (P=4.46E-08), where NT5DC1 and COL10A1 reside; the SEC23IP locus (P=6.47E-07); the PSD locus (P=7.58E-08) and ZCCHC4 locus (P=1.79E-06). No genome-wide significant association was observed among the common variants. The strongest signal was noted at rs9325032 in PPP2R2B (odds ratio=0.81, P=1.61E-05). Taken together, our data add to the growing evidence of general signal transduction molecules (NT5DC1, PSD, SEC23IP and ZCCHC4) having an important role in the etiology of ADHD. Although the biological implications of these findings need to be further explored, they highlight the possible role of cellular communication as a potential core component in the development of both adult and childhood forms of ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Sequenciamento do Exoma , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo Genético/genética , Adulto , Encéfalo/metabolismo , Feminino , Loci Gênicos/genética , Variação Genética , Genótipo , Humanos , Masculino , Fases de Leitura Aberta/genética
12.
Psychol Med ; 45(10): 2045-56, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25612927

RESUMO

BACKGROUND: Course and predictors of persistence of attention deficit hyperactivity disorder (ADHD) in adults are still largely unknown. Neurobiological and clinical differences between child and adult ADHD raise the need for follow-up studies of patients diagnosed during adulthood. This study investigates predictors of ADHD persistence and the possibility of full remission 7 years after baseline assessment. METHOD: A 7-year follow-up study of adults with ADHD (n = 344, mean age 34.1 years, 49.9% males) was conducted. Variables from different domains (social demographics, co-morbidities, temperament, medication status, ADHD measures) were explored with the aim of finding potential predictors of ADHD persistence. RESULTS: Retention rate was 66% (n = 227). Approximately a third of the sample (n = 70, 30.2%) did not maintain ADHD criteria and 28 (12.4%) presented full remission (<4 symptoms), independently of changes in co-morbidity or cognitive demand profiles. Baseline predictors of diagnostic persistence were higher number of inattention symptoms [odds ratio (OR) 8.05, 95% confidence interval (CI) 2.54-25.45, p < 0.001], number of hyperactivity/impulsivity symptoms (OR 1.18, 95% CI 1.04-1.34, p = 0.01), oppositional defiant disorder (OR 3.12, 95% CI 1.20-8.11, p = 0.02), and social phobia (OR 3.59, 95% CI 1.12-11.47, p = 0.03). CONCLUSIONS: Despite the stage of brain maturation in adults suggests stability, approximately one third of the sample did not keep full DSM-IV diagnosis at follow-up, regardless if at early, middle or older adulthood. Although full remission is less common than in childhood, it should be considered as a possible outcome among adults.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Estimulantes do Sistema Nervoso Central/uso terapêutico , Metilfenidato/uso terapêutico , Adolescente , Adulto , Idoso , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Brasil/epidemiologia , Comorbidade , Seguimentos , Hospitais de Ensino , Humanos , Entrevista Psicológica , Pessoa de Meia-Idade , Fobia Social/complicações , Fobia Social/psicologia , Análise de Regressão , Indução de Remissão , Resultado do Tratamento , Adulto Jovem
14.
Insect Mol Biol ; 19(2): 217-28, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20017754

RESUMO

In this study we characterize the transposable elements harrow, which belong to the hAT superfamily of DNA transposons. Searches for harrow sequences were performed in 65 Drosophilidae species, mainly representing Neotropical and cosmopolitan groups from the genus Drosophila. The nucleotide divergence among elements found in these species suggests that harrow sequences could be clustered in a subfamily. The patchy distribution throughout the genus Drosophila and the high similarity presented between all harrow sequences indicate that horizontal transfer could play a major role in the evolution of harrow elements. The results obtained suggest an evolutionary scenario in which harrow would have undergone multiple horizontal transfer events in the Neotropics, involving D. tripuncatata, D. mojavensis (Subgenus Drosophila) and several species of the willistoni and saltans groups (subgenus Sophophora).


Assuntos
Elementos de DNA Transponíveis/genética , Drosophila/genética , Transferência Genética Horizontal , Genes de Insetos , Animais , Sequência de Bases , Primers do DNA/genética , Drosophila/classificação , Evolução Molecular , Dados de Sequência Molecular , Filogenia , Seleção Genética , Especificidade da Espécie , Fatores de Tempo
15.
Transpl Infect Dis ; 11(6): 497-502, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19671120

RESUMO

Human herpesvirus-6 and -7 (HHV-6, HHV-7) remain latent after primary infection and can reactivate after transplantation. HHV-6 active infection has been related to some clinical manifestation, but the role of HHV-7 remains unclear. The clinical significance of HHV-7 DNAemia is not completely known and the immune response against HHV-7 has been poorly studied in transplantation. In this study, we investigated HHV-7 DNAemia in liver transplant recipients and evaluated the immunoglobulin (Ig) G and IgM response against HHV-7. A total of 22 adult liver transplant recipients were followed up for 90 days. HHV-7 DNAemia was detected by nested polymerase chain reaction (PCR) in DNA extracted from sera. IgG and IgM detection was performed by immunofluorescent assay using HHV-7-infected cord blood mononuclear cells. A significant virus antibody response was defined as either a positive IgM or a > or =4-fold rise in the virus IgG antibody. All patients had pre-transplant HHV-7-positive serostatus. Nine of 22 (40.9%) patients presented HHV-7 DNAemia during follow-up. All these patients had anti-HHV-7-positive IgM and/or significant increase in IgG titers with concurrent or subsequent DNAemia. In patients without DNAemia and low persistent IgG antibody titers, IgM was not detected. Correlation between nested PCR and IgM detection was statistically significant (P=0.01). Our study indicates that nested PCR in DNA extraction from serum can be useful to detect and monitor HHV-7 active infection in liver transplant recipients. IgM antibody detection also can be useful as a first immunological technique to detect active infection, especially if combined with PCR.


Assuntos
Anticorpos Antivirais/sangue , Herpesvirus Humano 7/isolamento & purificação , Transplante de Fígado/efeitos adversos , Reação em Cadeia da Polimerase/métodos , Infecções por Roseolovirus/diagnóstico , Adolescente , Adulto , Idoso , DNA Viral/sangue , DNA Viral/isolamento & purificação , Feminino , Imunofluorescência , Herpesvirus Humano 7/genética , Herpesvirus Humano 7/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Infecções por Roseolovirus/imunologia , Infecções por Roseolovirus/virologia , Adulto Jovem
16.
Vet Res Commun ; 32(2): 187-91, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17668284

RESUMO

In dogs, the canine transmissible venereal tumor (CTVT) is the only neoplasm which is not produced by neoplastic transformation of normal cells; the tumor is transmitted from the affected dog to healthy dogs by implantation of one or various clones of cancer cells. Thus, the CTVT of dogs analyzed in various countries reveals similar genetic characteristics and consequently CTVT is considered to have a clonal origin. The CTVTs obtained from dogs in Korea showed the T963C mutation on TP53 gene; this mutation was thought to be a molecular alteration which participates in the origin of the ancestral clone, CTVT. Nonetheless, this supposed mutation has not been identified in other studies which were carried out for the purpose of clarifying the clonal origin of CTVT. Thus we have considered it important to identify the role of the T963C mutation of the TP53 gene in the clonal origin of CTVT in dogs. Consequently the region which includes the mutation of the TP53 gene in twenty samples of CTVT obtained from various canine breeds was PCR amplified and afterwards its sequence of nucleotides was determined. We conclude that this mutation did not participate in the clonal origin of the tumor, but was acquired at a later stage.


Assuntos
Doenças do Cão/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Tumores Venéreos Veterinários/genética , Animais , Sequência de Bases , Cães , Regulação da Expressão Gênica/fisiologia , Filogenia , Mutação Puntual
17.
Arch Mal Coeur Vaiss ; 100(8): 704-8, 2007 Aug.
Artigo em Francês | MEDLINE | ID: mdl-17928781

RESUMO

Apelin is a peptide involved in the regulation of body fluid homeostasis and cardiovascular functions, that was recently isolated as the endogenous ligand for the human orphan APJ receptor, a G protein-coupled receptor which shares 31% amino-acid sequence identity with the angiotensin II type 1 receptor. The predominant molecular forms of apelin naturally occuring in vivo are apelin 36, apelin 17 (K17F) and the pyroglutamyl form of apelin 13 (pE13F). We investigated the structure-activity relationships of apelin at the rat apelin receptor, tagged at its C-terminal end with enhanced green fluorescent protein and stably expressed in CHO cells. We compared the abilities of N- and C-terminal deleted fragments of K17F (KFRRQRPRLSHKGPMPF) to bind with high affinity to the apelin receptor, to inhibit cAMP production and to induce apelin receptor internalization. The first five N-terminal and the last two C-terminal amino acids of K17F were not essential for apelin binding or cAMP response. In contrast, deletion of the arginine in position 6 drastically decreased binding and cAMP response. The full-length sequence of K17F was the most potent inducer of apelin receptor internalization because successive N-terminal amino-acid deletions progressively reduced internalization and the removal of a single amino acid, the phenylalanine in position 17 at the C-terminus of K17F abolished this process. Thus, K16P binds with high affinity to the apelin receptor and strongly inhibits cAMP production, but does not induce apelin receptor endocytosis. These data indicate that apelin receptor signaling (coupling to Gi) and endocytosis are functionally dissociated, possibly reflecting the existence of several conformational states of this receptor, stabilized by the binding of different apelin fragments to the receptor. We then investigated the consequences for biological activity of this functional dissociation by evaluating the effects of various apelin fragments, injected iv, on arterial blood pressure in normotensive Wistar Kyoto rats. We showed that apelin fragments, that did not induce receptor internalization in vitro but kept their ability to activate receptor coupling to Gi, did not decrease arterial blood pressure. Our data showed that hypotensive actions of apelin peptides correlate with the ability of those ligands to internalize. Thus, the depressor response of apelin may be controlled by apelin receptor endocytosis, which is probably required for initiation of a second wave of signal transduction. The development of biaised agonists of the apelin receptor capable of promoting only one specific signal transduction pathway may therefore offer new therapeutic avenues for the treatment of cardiovascular disorders.


Assuntos
Pressão Sanguínea/fisiologia , Proteínas de Transporte/fisiologia , Endocitose/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Animais , Apelina , Pressão Sanguínea/efeitos dos fármacos , Proteínas de Transporte/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular , Fragmentos de Peptídeos/farmacologia , Ratos , Ratos Endogâmicos WKY , Transdução de Sinais/fisiologia , Relação Estrutura-Atividade
18.
J Pept Res ; 65(2): 175-88, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15705162

RESUMO

Aminopeptidase A (APA) is involved in the maturation of angiotensin III, a peptide which seems to be implicated in blood pressure regulation at the brain level. Therefore APA inhibitors are potential new antihypertensive agents with possible novel applications. With the aim of enhancing the bioavailability and potency of EC 33, the APA inhibitor (Ki = 300 nM) initially used in the earlier studies, we have synthesized new non-peptidic inhibitors able to interact with the S1 and S'1 subsites of the targeted enzyme. Compound 10a, (3S,4S)-3-amino-4-mercapto-6-phenyl-hexane-1-sulfonic acid was obtained using an asymmetric synthesis. Inhibitor 10a exhibits a Ki value of 30 nm.


Assuntos
Anti-Hipertensivos/síntese química , Anti-Hipertensivos/farmacologia , Glutamil Aminopeptidase/antagonistas & inibidores , Inibidores de Proteases/síntese química , Inibidores de Proteases/farmacologia , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/farmacologia , Ácidos Sulfônicos/síntese química , Ácidos Sulfônicos/farmacologia , Animais , Humanos , Ácidos Sulfônicos/química
19.
J Chem Phys ; 120(13): 6268-73, 2004 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15267514

RESUMO

We study dynamical properties of ionic species in aqueous solutions of dodecyltrimethylammonium bromide, for several concentrations below and above the critical micellar concentration (cmc). New experimental determinations of the electrical conductivity are given which are compared to results obtained from an analytical transport theory; transport coefficients of ions in these solutions above the cmc are also computed from Brownian dynamics simulations. Analytical calculations as well as the simulation treat the solution within the framework of the continuous solvent model. Above the cmc, three ionic species are considered: the monomer surfactant, the micelle and the counterion. The analytical transport theory describes the structural properties of the electrolyte solution within the mean spherical approximation and assumes that the dominant forces which determine the deviations of transport processes from the ideal behavior (i.e., without any interactions between ions) are hydrodynamic interactions and electrostatic relaxation forces. In the simulations, both direct interactions and hydrodynamic interactions between solutes are taken into account. The interaction potential is modeled by pairwise repulsive 1/r(12) interactions and Coulomb interactions. The input parameters of the simulation (radii and self-diffusion coefficients of ions at infinite dilution) are partially obtained from the analytical transport theory which fits the experimental determinations of the electrical conductivity. Both the electrical conductivity of the solution and the self-diffusion coefficients of each species computed from Brownian dynamics are compared to available experimental data. In every case, the influence of hydrodynamic interactions (HIs) on the transport coefficients is investigated. It is shown that HIs are crucial to obtain agreement with experiments. In particular, the self-diffusion coefficient of the micelle, which is the largest and most charged species in the present system, is enhanced when HIs are included whereas the diffusion coefficients of the monomer and the counterion are roughly not influenced by HIs.

20.
Cochrane Database Syst Rev ; (2): CD001357, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12076408

RESUMO

BACKGROUND: The treatment of schizophrenia with old, 'typical' antipsychotic drugs such as haloperidol can be problematic, because many people treated with these drugs will suffer from movement disorders. Amisulpride is said to be an "atypical" antipsychotic which induces less movement disorder and which is effective for the negative symptoms of schizophrenia. OBJECTIVES: To evaluate the effects of amisulpride as compared with placebo, typical and atypical antipsychotic drugs for schizophrenia. SEARCH STRATEGY: The authors carried out electronic searches of Biological Abstracts (1982-1999), CINAHL (1982-1999), Cochrane Library (Issue 4, 1999), Cochrane Schizophrenia Group's Register (November 2000), EMBASE (1980-1999), LILACS(1982-1999), MEDLINE (1966-1999) and PsycLIT (1974-1999). They checked all identified studies for further trial citations, and sought these studies in the Science Citation Index. They also contacted authors of trials and the manufacturer of amisulpride. SELECTION CRITERIA: All randomised controlled trials comparing amisulpride to placebo, typical or atypical antipsychotic drugs for schizophrenia or other non-affective serious mental illnesses. DATA COLLECTION AND ANALYSIS: Data were independently extracted and analysed on an intention-to-treat basis. The relative risk (RR) and 95% confidence intervals (CI) of dichotomous data were calculated using a random effects model, and, where possible, the number needed to treat was calculated. Weighted mean differences (WMD) were calculated for continuous data. MAIN RESULTS: This review currently includes 19 randomised studies with a total of 2443 participants. Most trials were of short duration. Data from 4 trials with 514 participants with predominantly negative symptoms suggest that low-dose (up to 300mg/day) amisulpride was a more acceptable treatment than placebo (n=514, RR 0.6 CI 0.5 to 0.8, NNT 3 CI 3 to 7), the improvement of the participants' global state (n=242, RR 0.6 CI 0.5 to 0.8, NNT 3 CI 2 to 6) and the treatment of negative symptoms (n=177, WMD -10.1 CI -16.6 to -3.5). Amisulpride was shown to be more likely to cause extrapyramidal symptoms than placebo in two studies (n=269, RR 2.2 CI 1.2 to 4.2), but this result did not hold calculating the risk reduction so that an NNT-statistic could not be indicated. Compared to typical antipsychotics, the pooled results of a total of fourteen trials suggest that amisulpride was more effective in improving global state (n=651, RR 0.7 CI 0.5 to 0.9, NNT 6 CI 4 to 11), the general mental state (n=695, WMD -4.2 CI -6.5 to -1.9) and the negative symptoms of schizophrenia (n=506, WMD -2.8 CI -4.3 to -1.3). Regarding positive symptoms, amisulpride was as effective as typical antipsychotics. Amisulpride was less prone to cause at least one general adverse event (n=751, RR 0.9 CI 0.8 to 0.97, NNH 9 CI 6 to 18), one extrapyramidal symptom (n=771, RR 0.7 CI 0.6 to 0.9, NNH 5 CI 4 to 9) or to require the use of antiparkinson medication (n=851, RR 0.6 CI 0.5 to 0.8, NNH 4 CI 3 to 6). No clear differences in other adverse events compared to typical drugs were found. Amisulpride also seemed to be more acceptable than conventional drugs as measured by the outcome 'leaving the studies early' (n=1512, RR 0.8 CI 0.7 to 0.9, NNT 16 CI 9 to 69) than conventional drugs, but this result might have been overestimated due to a publication bias which could not be excluded with certainty. A single trial compared amisulpride to another 'atypical' antipsychotic, risperidone. With the exception of agitation, which was more frequent in the amisulpride group (n=228, RR 3.4 CI 1.2 to 10.1, NNH 11 CI 6 to 50) no significant differences were recorded on efficacy or acceptability. REVIEWER'S CONCLUSIONS: This systematic review confirms that amisulpride is an effective 'atypical' antipsychotic drug for those with schizophrenia. Amisulpride may offer a good general profile, at least compared to high-potency 'typical' antipsychotics. It may also yield better results in some specific outcomes related to efficacy, such as improvement of global state and general negative symptoms. It might be more acceptable and more tolerable than high-potency conventional antipsychotics, especially regarding extrapyramidal side-effects. Longer term randomised trials are needed to evaluate the comparative value of amisulpride, particularly compared to other expensive atypical antipsychotics. These should focus on important outcomes which have not been sufficiently monitored such as service use, family burden and quality of life.


Assuntos
Antipsicóticos/uso terapêutico , Esquizofrenia/tratamento farmacológico , Sulpirida/análogos & derivados , Sulpirida/uso terapêutico , Amissulprida , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
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