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1.
Biochemistry ; 63(16): 2023-2029, 2024 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-39106042

RESUMO

The kallikrein-related peptidase KLK2 has restricted expression in the prostate luminal epithelium, and its protein target is unknown. The present work reports the hydrolytic activities of KLK2 on libraries of fluorescence resonance energy-transfer peptides from which the sequence SYRIF was the most susceptible substrate for KLK2. The sequence SYRIF is present at the extracellular N-terminal segment (58SYRIF63Q) of IL-10R2. KLK2 was fully active at pH 8.0-8.2, found only in prostate inflammatory conditions, and strongly activated by sodium citrate and glycosaminoglycans, the quantities and structures controlled by prostate cells. Bone-marrow-derived macrophages (BMDM) have IL-10R2 expressed on the cell surface, which is significantly reduced after KLK2 treatment, as determined by flow cytometry (FACS analysis). The IL-10 inhibition of the inflammatory response to LPS/IFN-γ in BMDM cells due to decreased nitric oxide, TNF-α, and IL-12 p40 levels is significantly reduced upon treatment of these cells with KLK2. Similar experiments with KLK3 did not show these effects. These observations indicate that KLK2 proteolytic activity plays a role in prostate inflammation and makes KLK2 a promising target for prostatitis treatment.


Assuntos
Calicreínas , Humanos , Masculino , Calicreínas/metabolismo , Calicreínas/química , Arginina/metabolismo , Arginina/química , Próstata/metabolismo , Próstata/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Animais , Camundongos , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/metabolismo , Domínios Proteicos , Interleucina-10/metabolismo , Especificidade por Substrato
2.
Phytother Res ; 36(9): 3415-3443, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35848908

RESUMO

Thymol (THY) exhibits antibacterial and antioxidant properties. Recent studies have also shown that THY presents anti-inflammatory and healing properties. This review focused on in vitro and in vivo investigations related to THY utilization, as an anti-inflammatory and/or wound healing agent. PubMed, WebOfScience, and Scopus were examined. Independent reviewers conducted all diagram steps. PRISMA was followed for data extraction. RoB 2 and SYRCLE were utilized to assess the risk of bias for in vitro and animal studies. Meta-analysis was performed for in vitro and in vivo articles that investigated THY as an anti-inflammatory agent. Thirty-six and 15 articles were included in the qualitative analysis and meta-analysis, respectively. Studies showed high risk of bias related to sampling, allocation procedures, randomization, and blinding. Even so, for in vitro studies, significant result was observed for IL-2. For in vivo studies, significant results were found for IL-1, IL-17, TNF-α, AST, MPO, and CRP, with higher levels noticed in control groups. THY presents significant properties as anti-inflammatory, ameliorating affections of the digestive system, cardiovascular problems, respiratory system and dermal damages, and burns. Researches are needed to clarify THY dose-response relationship and its mechanism of action, especially in the application of THY as a healing agent.


Assuntos
Queimaduras , Timol , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológico , Timol/farmacologia , Timol/uso terapêutico , Cicatrização
3.
Biochim Biophys Acta Proteins Proteom ; 1865(5): 558-564, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28254587

RESUMO

Human kallikrein 6 (KLK6) is highly expressed in the central nervous system and with elevated level in demyelinating disease. KLK6 has a very restricted specificity for arginine (R) and hydrolyses myelin basic protein, protein activator receptors and human ionotropic glutamate receptor subunits. Here we report a previously unreported activity of KLK6 on peptides containing clusters of basic amino acids, as in synthetic fluorogenic peptidyl-Arg-7-amino-4-carbamoylmethylcoumarin (peptidyl-ACC) peptides and FRET peptides in the format of Abz-peptidyl-Q-EDDnp (where Abz=ortho-aminobenzoic acid and Q-EDDnp=glutaminyl-N-(2,4-dinitrophenyl) ethylenediamine), in which pairs or sequences of basic amino acids (R or K) were introduced. Surprisingly, KLK6 hydrolyzed the fluorogenic peptides Bz-A-R↓R-ACC and Z-R↓R-MCA between the two R groups, resulting in non-fluorescent products. FRET peptides containing furin processing sequences of human MMP-14, nerve growth factor (NGF), Neurotrophin-3 (NT-3) and Neurotrophin-4 (NT-4) were cleaved by KLK6 at the same position expected by furin. Finally, KLK6 cleaved FRET peptides derived from human proenkephalin after the KR, the more frequent basic residues flanking enkephalins in human proenkephalin sequence. This result suggests the ability of KLK6 to release enkephalin from proenkephalin precursors and resembles furin a canonical processing proteolytic enzyme. Molecular models of peptides were built into the KLK6 structure and the marked preference of the cut between the two R of the examined peptides was related to the extended conformation of the substrates.


Assuntos
Calicreínas/metabolismo , Cinética , Peptídeo Hidrolases/metabolismo , Peptídeos/química , Aminoácidos Básicos/química , Aminoácidos Básicos/genética , Encefalinas/química , Encefalinas/metabolismo , Transferência Ressonante de Energia de Fluorescência , Furina/química , Furina/metabolismo , Humanos , Hidrólise , Calicreínas/química , Calicreínas/genética , Metaloproteinase 14 da Matriz/química , Metaloproteinase 14 da Matriz/metabolismo , Modelos Moleculares , Fator de Crescimento Neural/química , Fator de Crescimento Neural/metabolismo , Fatores de Crescimento Neural/química , Fatores de Crescimento Neural/metabolismo , Neurotrofina 3 , Peptídeo Hidrolases/química , Peptídeo Hidrolases/genética , Peptídeos/metabolismo , Conformação Proteica , Precursores de Proteínas/química , Precursores de Proteínas/metabolismo , Proteólise , Especificidade por Substrato
4.
Biochim Biophys Acta ; 1854(1): 73-83, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25448018

RESUMO

KLK7 substrate specificity was evaluated by families of fluorescence resonance energy transfer (FRET) peptides derived from Abz-KLFSSK-Q-EDDnp (Abz=ortho-aminobenzoic acid and Q-EDDnp=glutaminyl-N-[2,4-dinitrophenyl] ethylenediamine), by one bead-one peptide FRET peptide library in PEGA resin, and by the FRET peptide libraries Abz-GXX-Z-XX-Q-EDDnp (Z and X are fixed and random natural amino acids, respectively). KLK7 hydrolyzed preferentially F, Y or M, and its S1' and S2' subsites showed selectivity for hydrophilic amino acids, particularly R and K. This set of specificities was confirmed by the efficient kininogenase activity of KLK7 on Abz-MISLM(↓)KRPPGFSPF(↓)RSSRI-NH2 ((↓)indicates cleavage), hydrolysis of somatostatin and substance P and inhibition by kallistatin. The peptide Abz-NLY(↓)RVE-Q-EDDnp is the best synthetic substrate so far described for KLK7 [kcat/Km=455 (mMs)(-1)] that was designed from the KLK7 substrate specificity analysis. It is noteworthy that the NLYRVE sequence is present in human semaphorin 6B. KLK7 is activated by GAGs, inhibited by neutral salts, and activated by high concentration of kosmotropic salt. Pyroglutamic acid inhibited KLK7 (Ki=33mM) and is present in skin moisturizing factor (124mM). The KLK7 specificity described here and elsewhere reflects its participation in patho-physiological events in skin, the gastrointestinal tract and central nervous system, where KLK7 is significantly expressed.


Assuntos
Glicosaminoglicanos/farmacologia , Calicreínas/metabolismo , Peptídeo Hidrolases/metabolismo , Peptídeos/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Biocatálise/efeitos dos fármacos , Transferência Ressonante de Energia de Fluorescência , Humanos , Hidrólise/efeitos dos fármacos , Cinética , Cininogênios/metabolismo , Dados de Sequência Molecular , Concentração Osmolar , Ácido Pirrolidonocarboxílico/farmacologia , Semaforinas/metabolismo , Serpinas/metabolismo , Somatostatina/metabolismo , Substância P/metabolismo , Especificidade por Substrato , Fatores de Tempo
5.
Biochim Biophys Acta ; 1844(7): 1260-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24726393

RESUMO

The substrate specificity of TcoCBc1 was evaluated using two internally quenched fluorescent peptide libraries with randomized sequences designed to detect carboxydipeptidase (Abz-GXXZXK(Dnp)-OH) and endopeptidase (Abz-GXXZXXQ-EDDnp) activities at acidic and neutral pHs, respectively. All the data obtained with TcoCBc1 were compared with those of human cathepsin B, including the pH profiles of the hydrolytic reactions. The most relevant observation is the preference of TcoCBc1 for substrates with a pair of acidic amino acids at positions P(2) and P(1) for its carboxydipeptidase activity and the well acceptance for E and D at P(1) position for endopeptidase activity. These peculiar preferences for negatively charged groups of TcoCBc1 and its requirements for carboxydipeptidase activity were also observed on Abz labeled analogues of bradykinin (Abz-RPPG(↓)FSAFR-OH, Abz-RPPG(↓)FS(↓)AF-OH, Abz-RPPG(↓)DE(↓)AF-OH) and angiotensin I (Abz-DR(↓)VYIHAFHL-OH), where (↓) indicates the cleavage site. TcoCBc1 was modeled based on the atomic coordinates of the cathepsin B from Trypanosoma brucei and the positively charged environment in TcoCBc1 catalytic site contrasts with the negatively charged environment in human cathepsin B. The preferences of S1 and S2 subsites of TcoCBc1 for acidic amino acids have to be taken into consideration for future studies of physiological roles of TcoCBc1 as for instance in apoptotic processes of Trypanosoma congolense.


Assuntos
Angiotensina I/metabolismo , Bradicinina/metabolismo , Catepsina B/metabolismo , Fragmentos de Peptídeos/metabolismo , Trypanosoma congolense/enzimologia , Domínio Catalítico , Catepsina B/química , Transferência Ressonante de Energia de Fluorescência , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Modelos Moleculares , Biblioteca de Peptídeos , Conformação Proteica , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
6.
Biol Chem ; 396(1): 45-52, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25153237

RESUMO

A series of protease activated receptor 2 activating peptide (PAR2-AP) derivatives (1-15) were designed and synthesized. The obtained compounds were tested on a panel of human kallikreins (hKLK1, hKLK2, hKLK5, hKLK6, and hKLK7) and were found completely inactive toward hKLK1, hKLK2, and hKLK7. Aiming to investigate the mode of interaction between the most interesting compounds and the selected hKLKs, docking studies were performed. The described compounds distinguish the different human tissue kallikreins with compounds 1 and 5 as the best hKLK5 and hKLK6 inhibitors, respectively.


Assuntos
Calicreínas/antagonistas & inibidores , Receptor PAR-2/biossíntese , Humanos , Modelos Moleculares , Receptor PAR-2/genética
7.
Scand J Infect Dis ; 45(6): 478-83, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23286738

RESUMO

Pleural effusion (PE), a complication of community-acquired pneumonia (CAP), is usually attributed to a bacterial infection. Nonetheless, viral infections have not been investigated routinely. We searched for bacterial and viral infections among 277 children hospitalized with CAP. Among these children 206 (74%) had radiographic confirmation, of whom 25 (12%) had PE. The aetiology was established in 18 (72%) PE cases: bacterial (n = 5; 28%), viral (n = 9; 50%), and viral-bacterial (n = 4; 22%) infections were found. Infection by rhinovirus (n = 3), enterovirus, Streptococcus pneumoniae (n = 2 each), Haemophilus influenzae, Moraxella catarrhalis, Mycoplasma pneumoniae, influenza A virus, and respiratory syncytial virus (RSV) (n = 1 each) were detected as probable sole infections. Parainfluenza virus 1/3 + influenza A virus and RSV + influenza A virus (n = 1 each) were identified as mixed viral-viral infections. Probable viral non-bacterial infection was identified in a third of the cases with CAP and PE. It is advisable to investigate viral as well as bacterial infections among children with CAP and PE.


Assuntos
Infecções Comunitárias Adquiridas/virologia , Derrame Pleural/virologia , Pneumonia/virologia , Viroses/virologia , Brasil/epidemiologia , Pré-Escolar , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Feminino , Humanos , Lactente , Masculino , Derrame Pleural/epidemiologia , Derrame Pleural/microbiologia , Pneumonia/epidemiologia , Pneumonia/microbiologia , Estatísticas não Paramétricas , Viroses/epidemiologia , Viroses/microbiologia
8.
Arch Biochem Biophys ; 498(1): 74-82, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20371359

RESUMO

We report the enzymatic properties and substrate specificity of human recombinant KLK3 in the presence of glycosaminoglycans (GAGs) and sodium citrate. This salt is highly concentrated in prostate and in its presence KLK3 had a similar hydrolytic efficiency as chymotrypsin. In contrast to the latter peptidase, KLK3 activated by sodium citrate efficiently hydrolyzed substrates containing R, H and P at the P1 position. Activated KLK3 also cleaved peptides derived from the bradykinin domain of human kininogen at the same sites as human kallikrein KLK1, but presented low kininogenase activity. Angiotensin I has several sites for hydrolysis by KLK3; however, it was cleaved only at the Y-I bond (DRVY downward arrowIHPFHL). Sodium citrate modulated KLK3 conformation as observed by alterations to the intrinsic fluorescence of phenylalanines and tryptophans. Activated KLK3 was reversibly inhibited by Z-Pro-Prolinal and competitively inhibited by ortho-phenantroline. Together, these are noteworthy observations for the future design of specific non-peptide inhibitors of KLK3 and to find natural substrates.


Assuntos
Citratos/farmacologia , Glicosaminoglicanos/farmacologia , Calicreínas/antagonistas & inibidores , Calicreínas/metabolismo , Inibidores de Proteases/farmacologia , Sequência de Aminoácidos , Angiotensinas/metabolismo , Cloretos/química , Cloretos/farmacologia , Ativação Enzimática/efeitos dos fármacos , Transferência Ressonante de Energia de Fluorescência , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Calicreínas/química , Cininogênio de Baixo Peso Molecular/metabolismo , Dados de Sequência Molecular , Antígeno Prostático Específico , Sais/química , Sais/farmacologia , Citrato de Sódio , Especificidade por Substrato
9.
Scand J Infect Dis ; 42(11-12): 839-44, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20608763

RESUMO

Community-acquired pneumonia (CAP) is a common cause of morbidity among children. Evidence on seasonality, especially on the frequency of viral and bacterial causative agents is scarce; such information may be useful in an era of changing climate conditions worldwide. To analyze the frequency of distinct infections, meteorological indicators and seasons in children hospitalized for CAP in Salvador, Brazil, nasopharyngeal aspirate and blood were collected from 184 patients aged < 5 y over a 21-month period. Fourteen microbes were investigated and 144 (78%) cases had the aetiology established. Significant differences were found in air temperature between spring and summer (p = 0.02) or winter (p < 0.001), summer and fall (p = 0.007) or winter (p < 0.001), fall and winter (p = 0.002), and on precipitation between spring and fall (p = 0.01). Correlations were found between: overall viral infections and relative humidity (p = 0.006; r = 0.6) or precipitation (p = 0.03; r = 0.5), parainfluenza and precipitation (p = 0.02; r = -0.5), respiratory syncytial virus (RSV) and air temperature (p = 0.048; r = -0.4) or precipitation (p = 0.045; r = 0.4), adenovirus and precipitation (p = 0.02; r = 0.5), pneumococcus and air temperature (p = 0.04; r = -0.4), and Chlamydia trachomatis and relative humidity (p = 0.02; r = -0.5). The frequency of parainfluenza infection was highest during spring (32.1%; p = 0.005) and that of RSV infection was highest in the fall (36.4%; p < 0.001). Correlations at regular strength were found between several microbes and meteorological indicators. Parainfluenza and RSV presented marked seasonal patterns.


Assuntos
Bactérias/classificação , Infecções Comunitárias Adquiridas/epidemiologia , Pneumonia Bacteriana/epidemiologia , Pneumonia Viral/epidemiologia , Vírus/classificação , Bactérias/isolamento & purificação , Sangue/microbiologia , Sangue/virologia , Brasil/epidemiologia , Pré-Escolar , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/virologia , Feminino , Humanos , Umidade , Lactente , Recém-Nascido , Masculino , Nasofaringe/microbiologia , Nasofaringe/virologia , Pneumonia Bacteriana/microbiologia , Pneumonia Viral/microbiologia , Prevalência , Chuva , Estações do Ano , Temperatura , Clima Tropical , Vírus/isolamento & purificação
10.
Biodivers Data J ; 8: e59664, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33424242

RESUMO

BACKGROUND: Brazilian protected areas are essential for plant conservation in the Atlantic Forest domain, one of the 36 global biodiversity hotspots. A major challenge for improving conservation actions is to know the plant richness, protected by these areas. Online databases offer an accessible way to build plant species lists and to provide relevant information about biodiversity. A list of land plants of "Parque Nacional do Caparaó" (PNC) was previously built using online databases and published on the website "Catálogo de Plantas das Unidades de Conservação do Brasil." Here, we provide and discuss additional information about plant species richness, endemism and conservation in the PNC that could not be included in the List. We documented 1,791 species of land plants as occurring in PNC, of which 63 are cited as threatened (CR, EN or VU) by the Brazilian National Red List, seven as data deficient (DD) and five as priorities for conservation. Fifity-one species were possible new ocurrences for ES and MG states. NEW INFORMATION: "Parque Nacional do Caparaó" houses 8% of the land plant species endemic to the Brazilian Atlantic Forest, including 6% of its angiosperms, 31% of its lycophytes and ferns and 14% of its avascular plants. Twelve percent of the threatened species listed for the State of Espírito Santo and 7% listed for the State of Minas Gerais are also protected by PNC. Surprisingly, 79% of the collections analysed here were carried out in Minas Gerais, which represents just 21% of the total extension of the Park. The compiled data uncover a huge botanical collection gap in this federally-protected area.

11.
Biodivers Data J ; 8: e50837, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508509

RESUMO

BACKGROUND: Brazil is one of the most biodiverse countries in the world, with about 37,000 species of land plants. Part of this biodiversity is within protected areas. The development of online databases in the last years greatly improved the available biodiversity data. However, the existing databases do not provide information about the protected areas in which individual plant species occur. The lack of such information is a crucial gap for conservation actions. This study aimed to show how the information captured from online databases, cleaned by a protocol and verified by taxonomists allowed us to obtain a comprehensive list of the vascular plant species from the "Parque Nacional do Itatiaia", the first national park founded in Brazil. All existing records in the online database JABOT (15,100 vouchers) were downloaded, resulting in 11,783 vouchers identified at the species level. Overall, we documented 2,316 species belonging to 176 families and 837 genera of vascular plants in the "Parque Nacional do Itatiaia". Considering the whole vascular flora, 2,238 species are native and 78 are non-native. NEW INFORMATION: The "Parque Nacional do Itatiaia" houses 13% of the angiosperm and 37% of the fern species known from the Brazilian Atlantic Forest. Amongst these species, 82 have been cited as threatened, following IUCN categories (CR, EN or VU), seven are data deficient (DD) and 15 have been classified as a conservation priority, because they are only known from a single specimen collected before 1969.

12.
Pediatr Infect Dis J ; 27(10): 939-41, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18756190

RESUMO

We report an investigation for 16 bacteria and viruses among 184 children hospitalized with pneumonia in Salvador, Brazil. Etiology was established in 144 (78%) cases. Viral, bacterial, and mixed infections were found in 110 (60%), 77 (42%), and 52 (28%) patients, respectively. Rhinovirus (21%) and Streptococcus pneumoniae (21%) were the most common pathogens. Our results demonstrate the importance of viral and pneumococcal infections among those patients.


Assuntos
Infecções Comunitárias Adquiridas/epidemiologia , Pneumonia Bacteriana/epidemiologia , Pneumonia Viral/epidemiologia , Infecções Respiratórias/epidemiologia , Brasil/epidemiologia , Pré-Escolar , Infecções Comunitárias Adquiridas/diagnóstico , Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/virologia , Países em Desenvolvimento , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pneumonia Bacteriana/diagnóstico , Pneumonia Bacteriana/microbiologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/microbiologia , Infecções Respiratórias/virologia
13.
Infect Dis (Lond) ; 50(9): 705-713, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29688138

RESUMO

BACKGROUND: We studied Immunoglobulin G (IgG) antibody responses against Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis in young children with acute viral type respiratory infection and analyzed the findings in a multivariate model including age, nasopharyngeal carriage of the tested bacteria and pneumococcal vaccination. METHODS: We included 227 children aged 6-23 months with acute respiratory infection. Nasopharyngeal aspirates were tested for bacterial carriage through detection of messenger RNA (mRNA) transcript with nCounter analysis. Acute and convalescent serum samples were tested for IgG antibody response against eight pneumococcal proteins, three proteins from H. influenzae and five proteins from M. catarrhalis in a fluorescent multiplex immunoassay. RESULTS: A two-fold or greater increase in antibodies to S. pneumoniae, H. influenzae and M. catarrhalis was detected in 27.8, 9.7 and 14.1%, respectively. Nasopharyngeal carriage of each of the studied bacteria was not associated with antibody response detection against each respective bacterium. Furthermore, neither age nor pneumococcal vaccination were independently associated to detection of antibody response against the studied bacteria. Children who carried H. influenzae had higher frequency of colonization by M. catarrhalis (175 [80.3%] vs. 2 [22.2%]; p < .001) than those without H. influenzae. Also, children with acute otitis media tended to have higher frequency of antibody response to S. pneumoniae. CONCLUSION: Nasopharyngeal colonization by S. pneumoniae, H. influenzae and M. catarrhalis did not induce significant increases in antibody levels to these bacteria. Carriage of pathogenic bacteria in the nasopharynx is not able to elicit antibody responses to protein antigens similar to those caused by symptomatic infections.


Assuntos
Portador Sadio/microbiologia , Haemophilus influenzae/imunologia , Moraxella catarrhalis/imunologia , Nasofaringe/microbiologia , Infecções Respiratórias/imunologia , Streptococcus pneumoniae/imunologia , Doença Aguda , Anticorpos Antibacterianos/sangue , Feminino , Haemophilus influenzae/genética , Haemophilus influenzae/isolamento & purificação , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Lactente , Masculino , Moraxella catarrhalis/genética , Moraxella catarrhalis/isolamento & purificação , Análise Multivariada , Vacinas Pneumocócicas/administração & dosagem , Vacinas Pneumocócicas/imunologia , Infecções Respiratórias/microbiologia , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/isolamento & purificação
14.
J Clin Virol ; 106: 34-40, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30031351

RESUMO

BACKGROUND: Virus-specific molecular assays such as real-time polymerase chain reaction (RT-PCR) are regularly used as the gold standard to diagnose viral respiratory tract infections, but simultaneous detection of multiple different pathogens is often challenging. A multiplex digital method of RNA quantification, nCounter (NanoString Technologies), can overcome this disadvantage and identify, in a single reaction, the presence of different respiratory viruses. OBJECTIVES: To evaluate the accuracy of nCounter to identify and quantify RSV-A and RSV-B in nasopharyngeal aspirates (NPA) of children (6-23-months-old) with acute respiratory infection. STUDY DESIGN: NPA was collected at enrolment in a prospective cross-sectional study conducted in Salvador, Brazil. A quantitative RT-PCR with a subgroup-specific primer and probeset for RSV-A and RSV-B was performed in parallel with a customized nCounter probeset containing viral targets in NPA. RESULTS: Of 559 NPA tested, RSV was detected by RT-PCR in 139 (24.9%), by nCounter in 122 (21.8%) and by any method in 158 (28.3%) cases. Compared to the gold standard of qRT-PCR, sensitivity of nCounter was 74.3% (95%CI:63.3%-82.9% RSV-A) and 77.6% (95%CI:66.3%-85.9% RSV-B); specificity was 98.4% (95%CI:96.8%-99.2% RSV-A) and 97.8% (95%CI:96.0%-98.8% RSV-B); positive predictive value was 87.3% (95%CI:76.9%-93.4% RSV-A) and 82.5% (95%CI:71.4%-90.0% RSV-B) and negative predictive value was 96.1% (95%CI:94.1%-97.5% RSV-A), and 96.9% (95%CI:95.1%-98.2% RSV-B). Accuracy was 95.2% (95%CI:93.1%-96.7%) for RSV-A and 95.3% (95%CI:93.3%-96.9%) for RSV-B, while both methods significantly correlated for RSV-A (r = 0.44, p = 8 × 10-5) and RSV-B (r = 0.73, p = 3 × 10-12) quantification. CONCLUSIONS: nCounter is highly accurate in detecting RSV-A/B in NPA. Robustness and high-throughput multiplexing indicate its use in large-scale epidemiological studies.


Assuntos
Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , RNA Viral/análise , Infecções Respiratórias/diagnóstico , Doença Aguda/epidemiologia , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Lactente , Masculino , Nasofaringe/virologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Vírus Sincicial Respiratório Humano/genética , Vírus Sincicial Respiratório Humano/isolamento & purificação , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Sensibilidade e Especificidade
15.
Front Microbiol ; 9: 2475, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30473680

RESUMO

Acute respiratory infection (ARI) is the most frequent cause for hospitalization in infants and young children. Using multiplexed nCounter technology to digitally quantify 600 human mRNAs in parallel with 14 virus- and 5 bacterium-specific RNAs, we characterized viral and bacterial presence in nasopharyngeal aspirates (NPA) of 58 children with ARI and determined the corresponding in situ immune profiles. NPA contained different groups of organisms and these were classified into bacterial (n = 27), viral (n = 5), codetection [containing both viral and bacterial transcripts (n = 21), or indeterminate intermediate where microbial load is below threshold (n = 5)]. We then identified differentially expressed immune transcripts (DEITs) comparing NPAs from symptomatic children vs. healthy controls, and comparing children presenting NPAs with detectable microbial load vs. indeterminate. We observed a strong innate immune response in NPAs, due to the presence of evolutionarily conserved type I Interferon (IFN)-stimulated genes (ISG), which was correlated with total bacterial and/or viral load. In comparison with indeterminate NPAs, adaptive immunity transcripts discriminated among viral, bacterial, and codetected microbial profiles. In viral NPAs, B cell transcripts were significantly enriched among DEITs, while only type III IFN was correlated with viral load. In bacterial NPAs, myeloid cells and coinhibitory transcripts were enriched and significantly correlated with bacterial load. In conclusion, digital nCounter transcriptomics provide a microbial and immunological in situ "snapshot" of the nasopharyngeal interface in children with ARI. This enabled discrimination among viral, bacterial, codetection, and indeterminate transcripts in the samples using non-invasive sampling.

16.
Insect Biochem Mol Biol ; 89: 17-30, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28838758

RESUMO

Cathepsins L are the major digestive peptidases in the beetle Tenebrio molitor. Two digestive cathepsins L (TmCAL2 and TmCAL3) from it had their 3D structures solved. The aim of this paper was to study in details TmCAL3 specificity and properties and relate them to its 3D structure. Recombinant TmCAL3 was assayed with 64 oligopeptides with different amino acid replacements in positions P2, P1, P1' and P2'. Results showed that TmCAL3 S2 specificity differs from the human enzyme and that its specificities also explain why on autoactivation two propeptide residues remain in the enzyme. Data on free energy of binding and of activation showed that S1 and S2' are mainly involved in substrate binding, S1' acts in substrate binding and catalysis, whereas S2 is implied mainly in catalysis. Enzyme subsite residues were identified by docking with the same oligopeptide used for kinetics. The subsite hydrophobicities were calculated from the efficiency of hydrolysis of different amino acid replacements in the peptide and from docking data. The results were closer for S1 and S2' than for S1' and S2, indicating that the residue subsites that were more involved in transition state binding are different from those binding the substrate seen in docking. Besides TmCAL1-3, there are nine other cathepsins L, most of them more expressed at midgut. They are supposed to be directed to lysosomes by a Drosophila-like Lerp receptor and/or motifs in their prodomains. The mannose 6-phosphate lysosomal sorting machinery is absent from T. molitor transcriptome. Cathepsin L direction to midgut contents seems to depend on overexpression.


Assuntos
Catepsina L/metabolismo , Tenebrio/enzimologia , Sequência de Aminoácidos , Animais , Catálise , Catepsina L/química , Trato Gastrointestinal/enzimologia , Interações Hidrofóbicas e Hidrofílicas , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Lisossomos/enzimologia , Simulação de Acoplamento Molecular , Sinais Direcionadores de Proteínas , Especificidade por Substrato
17.
Vaccine ; 35(33): 4105-4111, 2017 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-28668567

RESUMO

BACKGROUND: The effect of pneumococcal vaccination is widely variable when measured by nasopharyngeal carriage of vaccine and non-vaccine targets. The aim of this study was to compare the carriage rates and metabolic activity of Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae and Moraxella catarrhalis among children who were or were not vaccinated with PCV10. METHODS: We included children with acute respiratory infection aged 6-23months from a cross-sectional study (CHIADO-IVAS). Nasopharyngeal aspirates were collected and respiratory pathogens were quantified by nCounter digital transcriptomics (Nanostring) and metagenomic sequencing of 16S ribosomal RNA (Illumina). The metabolic rate was calculated by the ratio between RNA transcripts and 16S DNA reads. RESULTS: Out of the 80 patients in this study, 53 were vaccinated with PCV10 and 27 were unvaccinated. There was no difference in nasopharyngeal carriage rates of S. pneumoniae, S. aureus, H. influenzae or M. catarrhalis by either transcriptomic analysis or 16S metagenomics. However, unvaccinated children presented a higher metabolic rate for S. pneumoniae compared to PCV10-vaccinated children (Median [25-75th percentiles]: 126 [22.75-218.41] vs. 0[0-47.83], p=0.004). Furthermore, unvaccinated children presented a positive correlation between mRNA counts and 16S DNA reads for S. pneumoniae (r=0.707; p<0.001) and H. influenzae (r=0.525; p=0.005), in contrast to vaccinated children. No such effect was observed for S. aureus and M. catarrhalis. CONCLUSIONS: Vaccination by PCV10 exerts a pathogen-specific effect on pneumococcal metabolic rate. Pathogen RNA/DNA ratio might represent a more sensitive readout for vaccine follow-up, as compared to nasopharyngeal carriage.


Assuntos
Portador Sadio/epidemiologia , Haemophilus influenzae/isolamento & purificação , Nasofaringe/microbiologia , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/isolamento & purificação , Portador Sadio/microbiologia , Estudos Transversais , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Feminino , Haemophilus influenzae/metabolismo , Humanos , Lactente , Masculino , Moraxella catarrhalis/isolamento & purificação , Moraxella catarrhalis/metabolismo , Vacinas Pneumocócicas/administração & dosagem , Prevalência , Estudos Prospectivos , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/metabolismo , Streptococcus pneumoniae/metabolismo
18.
Vaccine ; 34(23): 2556-61, 2016 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-27102819

RESUMO

BACKGROUND: Acute respiratory infection (ARI) is the most frequent reason for children being seen by doctors worldwide. We aimed to estimate the frequency of complications in children aged 6-23 months during ARI episode and to evaluate risk factors present on recruitment associated with complications after the universal implementation of pneumococcal vaccine (PCV10) in our region. METHODS: This prospective cohort enrolled children who had shown ARI for up to 7 days and who were subsequently followed up 14-21 days after, in Salvador, Brazil. Data on recruitment were registered. The vaccine card was personally checked. Complication was defined when hospitalization, pneumonia or acute otitis media (AOM) were informed during the follow-up visit. Pneumonia and AOM were diagnosed by a doctor. Multiple logistic regression analysis was performed. RESULTS: Of 576 children, 422 (73%) returned and 79 (19%; 95%CI: 15-23%) had complications. The mean interval between admission and follow-up was 23±13 days. Pneumonia (n=47; 11%), hospitalization (n=28; 7%), and AOM (n=17; 4%) were reported. Most of the patients presented one complication (n=66; 84%) followed by two (n=13; 16%). Report of fever (92% versus 79%; OR [95%CI]: 2.90 [1.18-7.14]), bird at home (24% versus 14%; OR [95%CI]: 2.13 [1.07-4.26]), ronchi (48% versus 36%; OR [95%CI]: 2.06 [1.16-3.67]) or crackles (17% versus 7%; OR [95%CI]: 2.36 [1.04-5.38]) on auscultation were directly associated with complications whereas PCV10 (59% versus 75%; OR [95%CI]: 0.46 [0.26-0.82]) was inversely associated. Bird at home (OR [95%CI]: 5.80 [1.73-19.38]) and ronchi (OR [95%CI]: 6.39 [1.96-20.85]) were associated with AOM; PCV10 was inversely associated with AOM (OR [95%CI]: 0.16 [0.05-0.52]). Crackles were associated with pneumonia (OR [95%CI]: 2.55 [1.01-6.40]). CONCLUSIONS: One fifth of the children presented complications. PCV10 was independently associated with lower odds of development of AOM. Bird at home and ronchi are risk factors of otitis. Crackles are associated with pneumonia.


Assuntos
Otite Média/epidemiologia , Vacinas Pneumocócicas/administração & dosagem , Pneumonia/epidemiologia , Infecções Respiratórias/epidemiologia , Brasil , Feminino , Humanos , Lactente , Modelos Logísticos , Masculino , Estudos Prospectivos , Sons Respiratórios , Infecções Respiratórias/complicações , Fatores de Risco , Vacinas Conjugadas/administração & dosagem
19.
Front Microbiol ; 7: 2141, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28119672

RESUMO

Enzymes have important features that may facilitate their application in industrial processes and have been used as alternatives to chemical catalysts. In particular, proteases can be isolated from microorganisms, which provide important sources of advantageous enzymes for industrial processes. For example, Eupenicillium javanicum is a filamentous fungus that has been shown to express industrially applicable enzymes and chemical components, such as antifungal compounds. The biotechnological potential of E. javanicum and proteases made us search a novel protease from this microorganism. The macromolecule was isolated, the main biochemical properties was evaluated, and the specificity of the protease subsites was determined. The protease was produced under solid-state bioprocess with wheat bran and isolated by two chromatography steps with yield of 27.5% and 12.4-fold purification. The molecular mass was estimated at 30 kDa. The N-terminal sequence of the first 20 amino acid residues was AVGAGYNASVALALEKALNN. The enzyme presented higher proteolytic activity at pH 6.0 and 60°C. The protease is stable at wide range of pH values and temperatures and in the presence of surfactants. The "primed" side of the catalytic site showed the highest catalytic efficiency of the enzyme isolated from E. javanicum. The S'1 subsite is responsible for catalyzing the protease reaction with substrates with tyrosine in P'1. These findings provide important insights into the biochemical characterization of a highly active protease from E. javanicum and may facilitate the development of industrial processes involving this protease.

20.
Medicine (Baltimore) ; 95(41): e5142, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27741144

RESUMO

Respiratory syncytial virus (RSV) is one of the most common etiological agents of childhood respiratory infections globally. Information on seasonality of different antigenic groups is scarce. We aimed to describe the frequency, seasonality, and age of children infected by RSV antigenic groups A (RSVA) and B (RSVB) among children with ARI in a 4-year period.Children (6-23 months old) with respiratory infection for ≤7 days were enrolled in a prospective cross-sectional study, from September, 2009 to October, 2013, in Salvador, in a tropical region of Brazil. Upon recruitment, demographic, clinical data, and nasopharyngeal aspirates (NPA) were collected. A multiplex quantitative real-time polymerase chain reaction (RT-PCR) with a group-specific primer and probeset for RSVA and RSVB was used. Seasonal distribution of infection by RSV different antigenic groups was evaluated by Prais-Wisten regression.Of 560 cases, the mean age was 11.4 ±â€Š4.5 months and there were 287 (51.3%) girls. Overall, RSV was detected in 139 (24.8%; 95% CI: 21.4%-28.5%) cases, RSVA in 74 (13.2%; 95% CI: 10.6%-16.2%) cases, and RSVB in 67 (12.0%; 95% CI: 9.5%-14.9%) cases. Two (0.4%; 95% CI: 0.06%-1.2%) cases had coinfection. RSVA frequency was 9.6%, 18.4%, 21.6%, and 3.1% in 2010, 2011, 2012, and 2013, respectively. RSVB frequency was 19.2%, 0.7%, 1.4%, and 35.4% in the same years. RSVA was more frequently found from August to January than February to July (18.2% vs. 6.4%, P < 0.001). RSVB was more frequently found (P < 0.001) between March and June (36.0%) than July to October (1.0%) or November to February (1.6%). RSVB infection showed seasonal distribution and positive association with humidity (P = 0.02) whereas RSVA did not. RSVA was more common among children ≥1-year-old (17.8% vs. 1.8%; P = 0.02), as opposed to RSVB (11.5% vs. 12.2%; P = 0.8).One quarter of patients had RSV infection. RSVA compromised more frequently children aged ≥1 year. RSVA predominated in 2011 and 2012 whereas RSVB predominated in 2010 and 2013. In regard to months, RSVA was more frequent from August to January whereas RSVB was more often detected between March and June. Markedly different monthly as well as yearly patterns for RSVA and RSVB reveal independent RSV antigenic groups' epidemics.


Assuntos
DNA Viral/análise , Infecções por Vírus Respiratório Sincicial/epidemiologia , Vírus Sincicial Respiratório Humano/genética , Doença Aguda , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Incidência , Lactente , Masculino , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , Infecções por Vírus Respiratório Sincicial/virologia , Fatores de Risco , Estações do Ano
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