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1.
Rev Assoc Med Bras (1992) ; 66(1): 48-54, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130381

RESUMO

INTRODUCTION: Systemic sclerosis (SSC) is an autoimmune disorder that affects several organs of unknown etiology, characterized by vascular damage and fibrosis of the skin and organs. Among the organs involved are the esophagus and the lung. OBJECTIVES: To relate the profile of changes in esophageal electromanometry (EM), the profile of skin involvement, interstitial pneumopathy (ILD), and esophageal symptoms in SSC patients. METHODS: This is an observational, cross-sectional study carried out at the SSC outpatient clinic of the Hospital de Clínicas of the Federal University of Uberlândia. After approval by the Ethics Committee and signed the terms of consent, 50 patients were initially enrolled, from 04/12/2014 to 06/25/2015. They were submitted to the usual investigations according to the clinical picture. The statistical analysis was descriptive in percentage, means, and standard deviation. The Chi-square test was used to evaluate the relationship between EM, high-resolution tomography, and esophageal symptoms. RESULTS: 91.9% of the patients had some manometric alterations. 37.8% had involvement of the esophageal body and lower esophageal sphincter. 37.8% had ILD. 24.3% presented the diffuse form of SSC. No association was found between manometric changes and clinical manifestations (cutaneous, pulmonary, and gastrointestinal symptoms). CONCLUSION: The present study confirms that esophageal motility alterations detected by EM are frequent in SSC patients, but may not be related to cutaneous extension involvement, the presence of ILD, or the gastrointestinal complaints of patients.


Assuntos
Transtornos da Motilidade Esofágica/fisiopatologia , Esôfago/fisiopatologia , Doenças Pulmonares Intersticiais/fisiopatologia , Manometria/métodos , Escleroderma Sistêmico/fisiopatologia , Adulto , Idoso , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Transtornos da Motilidade Esofágica/complicações , Transtornos da Motilidade Esofágica/diagnóstico por imagem , Esfíncter Esofágico Inferior/patologia , Esfíncter Esofágico Inferior/fisiopatologia , Esôfago/diagnóstico por imagem , Esôfago/patologia , Feminino , Hemaglutinação , Humanos , Doenças Pulmonares Intersticiais/complicações , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
2.
J Basic Microbiol ; 59(12): 1238-1247, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31613018

RESUMO

Penicillium griseoroseum lectin was 80-fold purified by successive DEAE Sepharose anion exchange and Sephadex G-100 gel permeation chromatography. P. griseoroseum lectin exhibited haemagglutination activity towards protease-treated rabbit erythrocytes. It showed specificity towards various carbohydrates such as d-mannose, N-acetyl-d-glucosamine, mucins, and so forth. P. griseoroseum lectin was found as a glycoprotein with glycan content of 4.33%. Purified P. griseoroseum lectin is homodimeric having a molecular mass of 57 kDa with subunit molecular mass of 28.6 kDa. Haemagglutination activity of purified P. griseoroseum lectin was completely stable from 25°C to 35°C at a pH range of 6-7.5. Lectin activity was not influenced by divalent metal ions and denaturants. P. griseoroseum lectin manifested mitogenicity towards mice splenocytes and activity reached a peak at 75 µg/ml of lectin concentration. P. griseoroseum lectin in microgram concentrations stimulated proliferation of mice splenocytes. Thus, P. griseoroseum lectin exhibits potential mitogenicity, which can be exploited for further biomedical applications.


Assuntos
Lectinas/química , Lectinas/isolamento & purificação , Mitógenos/química , Mitógenos/isolamento & purificação , Penicillium/química , Animais , Carboidratos/química , Cátions/metabolismo , Proliferação de Células/efeitos dos fármacos , Quelantes , Glicoproteínas/química , Hemaglutinação , Concentração de Íons de Hidrogênio , Lectinas/farmacologia , Masculino , Camundongos , Mitógenos/farmacologia , Peso Molecular , Multimerização Proteica , Estabilidade Proteica , Temperatura
4.
Ann Afr Med ; 18(3): 138-142, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31417014

RESUMO

Background: Urinary tract infection (UTI) caused by uropathogenic Escherichia coli (UPEC) strains is one of the most important community-acquired infections in the world. The presence of virulence factors is closely related with the pathogenesis of UTI. Methods: The present study was conducted on 150 isolates of UPEC obtained from symptomatic and asymptomatic cases of UTIs with significant counts (≥105 CFU/ml) during 1 year. UPEC isolates were studied for hemolysis on 5% sheep blood agar, mannose-sensitive hemagglutination (MSHA), mannose-resistant hemagglutination (MRHA), and biofilm formation by recommended methods. Patients with UTI due to UPEC showing virulence factors were evaluated for the treatment received and the outcome of treatment. These were compared with the outcomes of patients whose culture samples grew UPEC without demonstrable virulence factors. Results: The study showed hemolysin production in 40% of the isolates. Forty percent of the isolates showed the presence of P fimbriae (MRHA) and 60% showed Type 1 fimbriae (MSHA). Biofilm formation capacity of all UPEC isolates was classified into three categories, strong biofilm producers (4%), moderate biofilm producers (88%), and nonbiofilm producers (8%). Patients harboring all three virulence factors showed 76% recovery compared to patients harboring strains with no demonstrable virulence factors, who showed 100% recovery. Conclusion: The present study has shown the production of various virulent factors and developing drug resistance in UPEC. Treatment outcomes of patients harboring strains with no virulence factors seem to be better than the ones which contain multiple virulence factors. UPEC occurs because of multiple virulence factors. Biofilm formation and MRHA are more likely to be seen in catheterized patients. The drug resistance among UPEC is on rise; therefore, the selection of appropriate antibiotics (after antibiotic susceptibility testing) is must for proper treatment of patients and to avoid emergence of drug resistance. Significant number of the UPEC isolates was sensitive to nitrofurantoin, and half of the isolates were sensitive to cotrimoxazole, so treatment is by giving these drugs orally.


Assuntos
Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/efeitos dos fármacos , Escherichia coli Uropatogênica/patogenicidade , Antibacterianos/uso terapêutico , Infecções Comunitárias Adquiridas , Fímbrias Bacterianas/metabolismo , Hemaglutinação , Proteínas Hemolisinas/metabolismo , Humanos , Índia , Testes de Sensibilidade Microbiana , Nitrofurantoína/uso terapêutico , Resultado do Tratamento , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Infecções Urinárias/diagnóstico , Infecções Urinárias/tratamento farmacológico , Escherichia coli Uropatogênica/isolamento & purificação , Virulência , Fatores de Virulência/metabolismo
6.
Antonie Van Leeuwenhoek ; 112(11): 1655-1662, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31230158

RESUMO

Actinobacillus seminis, a commensal of ovine and caprine reproductive organs, is able to induce epididymitis in the small ruminants that it infects. In this work, we characterised two protein bands of approximately 150 kDa and 65 kDa. These proteins cross-reacted with a polyclonal serum against Gallibacterium anatis hemagglutinin and with a polyclonal serum from sheep with epididymitis, indicating that the proteins are expressed in vivo; the two proteins also interacted with biotin-labeled sheep fibrinogen and fibronectin, suggesting that they may function as adhesins. The participation of these proteins as adhesins was confirmed by a cultured human bladder cell-A. seminis adhesion assay and adherence inhibition by preincubation of A. seminis with polyclonal antiserum to the 150 kDa protein. Both proteins presented sequence identity with an A. seminis GroEL protein by mass spectrometry analysis and agglutinated glutaraldehyde-fixed sheep red blood cells. Immunogold labeling was observed by transmission electron microscopy on bacterial cells that were negatively stained, and a peroxidase reaction was detected in A. seminis biofilms, when an anti-A. seminis 150 kDa protein serum was used, indicating the presence of this protein on the surface of A. seminis and in biofilms. The A. seminis GroEL-homologue is a multifunctional protein that likely acts as a hemagglutinin.


Assuntos
Actinobacillus seminis/fisiologia , Eritrócitos/imunologia , Proteínas de Choque Térmico/imunologia , Proteínas de Choque Térmico/metabolismo , Aglutinação , Testes de Aglutinação , Animais , Anticorpos Antibacterianos , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas da Membrana Bacteriana Externa/metabolismo , Biofilmes , Adesão Celular , Eritrócitos/metabolismo , Proteínas de Choque Térmico/isolamento & purificação , Hemaglutinação , Hemaglutininas/metabolismo , Ovinos
7.
Molecules ; 24(12)2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31216664

RESUMO

Series of multivalent α-l-fucoside containing glycoclusters and variously decorated l-fucosides were synthesized to find potential inhibitors of fucose-specific lectins and study the structure-binding affinity relationships. Tri- and tetravalent fucoclusters were built using copper-mediated azide-alkyne click chemistry. Series of fucoside monomers and dimers were synthesized using various methods, namely glycosylation, an azide-alkyne click reaction, photoinduced thiol-en addition, and sulfation. The interactions between compounds with six fucolectins of bacterial or fungal origin were tested using a hemagglutination inhibition assay. As a result, a tetravalent, α-l-fucose presenting glycocluster showed to be a ligand that was orders of magnitude better than a simple monosaccharide for tested lectins in most cases, which can nominate it as a universal ligand for studied lectins. This compound was also able to inhibit the adhesion of Pseudomonas aeruginosa cells to human epithelial bronchial cells. A trivalent fucocluster with a protected amine functional group also seems to be a promising candidate for designing glycoconjugates and chimeras.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Lectinas/química , Lectinas/metabolismo , Fucose/química , Fucose/metabolismo , Hemaglutinação , Testes de Inibição da Hemaglutinação , Humanos , Ligação Proteica , Relação Estrutura-Atividade
8.
Indian J Med Res ; 149(1): 57-61, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31115376

RESUMO

Background & objectives: : Bacterial vaginosis (BV) involves the presence of a thick vaginal multispecies biofilm, where Gardnerella vaginalis is the predominant species. The reason for an increase in the number of G. vaginalis which are usually present as normal flora of the female genital tract in cases of BV, is not known. Hence, the objective of the present study was to compare the biotypes and virulence factors of G. vaginalis isolated from the genital tract of women with and without BV. Methods: : High vaginal swabs collected from 811 women of reproductive age were cultured. G. vaginalis isolates were biotyped and tested for adherence to vaginal epithelial cells, biofilm formation, agglutination of human red blood cells (RBCs), protease production, phospholipase production and surface hydrophobicity. Results: : Of the isolates from women with BV, 83.3 per cent (60/72) showed good adherence, 78.4 per cent (58/74) produced biofilm, 82.9 per cent (63/76) produced phospholipase, 67.1 per cent (51/76) produced protease, 77.3 per cent (58/75) were positive for surface hydrophobicity and 61.6 per cent (45/73) were positive for haemagglutination of human RBC. In case of G. vaginalis from non-BV women, 25 per cent (15/60) isolates showed good adherence, 18.4 per cent (9/49) biofilm production, 35 per cent (21/60) phospholipase, 36.6 per cent (22/60) protease, 41.7 per cent (25/60) surface hydrophobicity and 10.1 per cent (6/59) agglutination of human RBCs. Maximum number of isolates belonged to biotypes 6, 2 and 3. Biotype 3 was more associated with non-BV rather than BV; biotype 6, 2 and 1 were more associated with cases of BV. Maximum virulence factors were expressed by biotypes 6, 2 and 1. Interpretation & conclusions: : Virulence factors were more expressed by G. vaginalis isolates obtained from women with BV rather than from non-BV. Biotypes 6, 2 and 1 were more associated with cases of BV and expressed maximum virulence factors.


Assuntos
Gardnerella vaginalis/genética , Infecções do Sistema Genital/microbiologia , Vaginose Bacteriana/microbiologia , Fatores de Virulência/genética , Adolescente , Adulto , Técnicas de Tipagem Bacteriana , Biofilmes/crescimento & desenvolvimento , Células Epiteliais/microbiologia , Eritrócitos/imunologia , Eritrócitos/microbiologia , Feminino , Gardnerella vaginalis/classificação , Gardnerella vaginalis/patogenicidade , Regulação da Expressão Gênica/genética , Genitália Feminina/microbiologia , Hemaglutinação/genética , Hemaglutinação/imunologia , Humanos , Interações Hidrofóbicas e Hidrofílicas , Pessoa de Meia-Idade , Infecções do Sistema Genital/genética , Infecções do Sistema Genital/patologia , Propriedades de Superfície , Vagina/microbiologia , Vagina/patologia , Vaginose Bacteriana/genética , Vaginose Bacteriana/patologia , Adulto Jovem
9.
Biomed Res Int ; 2019: 1341370, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31016184

RESUMO

A novel lectin (ABL) was purified from the dried fruiting bodies of Agaricus bitorquis. An efficient 3-step purification protocol involved two consecutive steps of ion exchange chromatography on Q-Sepharose and SP-Sepharose and gel filtration by FPLC on Superdex 75. ABL is a monomeric protein with the molecular mass of 27.6 kDa, which is different from other lectins from genus Agaricus. Its N-terminal amino acid sequence is EYTISIRVYQTNPKGFNRPV which is unique and sharing considerably high similarity of other mushroom lectins. The hemagglutinating activity of the lectin was inhibited by inulin. Based on hemagglutination tests, ABL prefers rabbit, human type A, and AB erythrocytes to human type B and O erythrocytes. The lectin inhibits the activity of HIV-1 reverse transcriptase and the proliferation of leukemia cell (L1210) with an IC50 value of 4.69 and 4.97 µM, respectively. Furthermore, ABL demonstrates the highest mitogenic activity with a response of 24177.7 ± 940.6 [3H-methyl] thymidine counts per minute (CPM) at a concentration of 0.91 µM.


Assuntos
Agaricales/química , Agaricus/química , Proliferação de Células/efeitos dos fármacos , Transcriptase Reversa do HIV/antagonistas & inibidores , Inulina/metabolismo , Lectinas/farmacologia , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Hemaglutinação/efeitos dos fármacos , Testes de Hemaglutinação/métodos , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Coelhos
10.
Anal Biochem ; 571: 37-39, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30797745

RESUMO

Hemagglutination inhibition (HAI) assay is a simple method quantifying relative binding activities of glycan-lectin interactions. Currently, interpretation of HAI data remains a manual task depending on visual observation. In this study we developed a digital data reading method for HAI assay by using the area scanning function of a microplate reader. This was based on galectin-3-induced hemagglutination inhibition assay. OD values showed a four-parameter logistic correlation with concentrations of galectin-3 inhibitors (R2 ≥ 0.97), and IC50 values were obtained from the curve fitting. The method provides an objective and robust data interpretation for HAI assays conducted with chicken erythrocytes.


Assuntos
Técnicas Biossensoriais , Computadores Analógicos , Galectina 3/antagonistas & inibidores , Testes de Inibição da Hemaglutinação , Animais , Galinhas , Eritrócitos/efeitos dos fármacos , Hemaglutinação , Lectinas/química , Modelos Logísticos , Polissacarídeos/química
11.
Transfusion ; 59(S2): 1518-1521, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30730557

RESUMO

INTRODUCTION: There has been interest in using human blood products in nonhuman primate models of trauma to supplement human studies and to provide evidence to guide novel trauma resuscitation strategies. The compatibility of human RBCs has not been extensively studied in nonhuman primate species. METHODS: Whole blood samples were collected from five healthy, nontransfused, not previously pregnant Chinese-bred rhesus macaques. The whole blood was centrifuged, and the plasma was decanted from each sample. Group O-negative human RBCs were mixed with the plasma from the rhesus macaque monkeys. Compatibility testing was performed by an immediate spin test and polyspecific and monospecific anti-human globulin (AHG) tests in glass tubes. RESULTS: Immediate spin testing revealed three out of five plasma samples (60%) from rhesus macaques caused at least 1+ agglutination with the human RBCs. Polyspecific anti-human globulin (AHG) tests demonstrated that two of five plasma samples (40%) from rhesus macaques caused at least 1+ agglutination with the human RBC, while the monospecific AHG testing revealed that the incompatibility was caused by C3d, not IgG. CONCLUSION: Human RBCs are not compatible with the plasma of some, but not all, Chinese-bred rhesus macaques.


Assuntos
Sistema ABO de Grupos Sanguíneos/sangue , Testes de Aglutinação/métodos , Eritrócitos/química , Eritrócitos/metabolismo , Hemaglutinação , Imunoglobulina G/sangue , Sistema ABO de Grupos Sanguíneos/química , Animais , Feminino , Humanos , Macaca mulatta
12.
J Immunol ; 202(5): 1595-1611, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30683699

RESUMO

In therapeutic applications in which the Fc of IgG is critically important, the receptor binding and functional properties of the Fc are lost after deglycosylation or removal of the unique Asn297 N-X-(T/S) sequon. A population of Fcs bearing sialylated glycans has been identified as contributing to this functionality, and high levels of sialylation also lead to longer serum retention times advantageous for therapy. The efficacy of sialylated Fc has generated an incentive to modify the unique N-linked glycosylation site at Asn297, either through chemical and enzymatic methods or by mutagenesis of the Fc, that disrupts the protein-Asn297 carbohydrate interface. In this study, we took an alternative approach by inserting or deleting N-linked attachment sites into the body of the Fc to generate a portfolio of mutants with tailored effector functions. For example, we describe mutants with enhanced binding to low-affinity inhibitory human Fcγ and glycan receptors that may be usefully incorporated into existing Ab engineering approaches to treat or vaccinate against disease. The IgG1 Fc fragments containing complex sialylated glycans attached to the N-terminal Asn221 sequon bound influenza virus hemagglutinin and disrupted influenza A-mediated agglutination of human erythrocytes.


Assuntos
Hemaglutinação/genética , Fragmentos Fc das Imunoglobulinas/genética , Imunoglobulina G/genética , Orthomyxoviridae/genética , Polissacarídeos/genética , Receptores de IgG/genética , Glicosilação , Hemaglutinação/imunologia , Humanos , Fragmentos Fc das Imunoglobulinas/imunologia , Imunoglobulina G/imunologia , Mutação , Orthomyxoviridae/imunologia , Polissacarídeos/imunologia , Receptores de IgG/imunologia
13.
Microbiol Immunol ; 63(1): 11-20, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30599082

RESUMO

The type IX secretion system (T9SS) was originally discovered in Porphyromonas gingivalis, one of the pathogenic bacteria associated with periodontal disease and is now known to be present in many members of the phylum Bacteroidetes. The T9SS secretes a number of potent virulence factors, including the highly hydrolytic proteases called gingipains, across the outer membrane in P. gingivalis. To understand the entire machinery of T9SS, an exhaustive search for T9SS-related genes in P. gingivalis using the mariner family transposon (Tn) and Tn-seq analysis was performed. Seven hundred and two Tn insertion sites in Tn mutants with no colony pigmentation that is associated with Lys-gingipain (Kgp) defectiveness were determined, and it was found that the Tn was inserted in the kgp gene and 54 T9SS-related candidate genes. Thirty-three out of the 54 genes were already known as T9SS-related genes. Furthermore, deletion mutant analysis of the remaining 21 genes revealed that they were not related to the T9SS. The 33 T9SS-related genes include a gene for PGN_0297, which was found to be associated with the T9SS components PorK and PorN. A PGN_0297 gene deletion mutant was constructed, and it was found that the mutant showed no colony pigmentation, hemagglutination or gingipain activities, indicating that PGN_0297 was an essential component of the T9SS. The 33 genes did not include the six genes (gppX, omp17, porY, rfa, sigP and wzx) that were also reported as T9SS-related genes. gppX deletion and insertion mutants were constructed, and it was found that they did not show deficiency in the T9SS.


Assuntos
Sistemas de Secreção Bacterianos/genética , Sistemas de Secreção Bacterianos/metabolismo , Genes Bacterianos/genética , Porphyromonas gingivalis/genética , Porphyromonas gingivalis/metabolismo , Adesinas Bacterianas/metabolismo , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/genética , Cisteína Endopeptidases/metabolismo , Elementos de DNA Transponíveis/genética , DNA Bacteriano/genética , Regulação Bacteriana da Expressão Gênica , Hemaglutinação , Peptídeo Hidrolases/metabolismo , Pigmentação/genética , Pigmentação/fisiologia , Deleção de Sequência , Fatores de Virulência/genética
14.
Int J Biol Macromol ; 125: 53-60, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30500503

RESUMO

Lonchocarpus campestris (tribe Dalbergieae) possess a mannose biding lectin (LCaL) purified by ion exchange chromatography on DEAE-Sephacel, HiTrap DEAE FF and TSKgel engaged in AKTA-HPLC system. LCaL agglutinates trypsinized rabbit erythrocytes and its activity was maintained after incubation in a wide range of temperature (4-100 °C) and pH (4-9). The lectin had its apparent molecular weight evaluated by size-exclusion chromatography and SDS-PAGE and presented a profile of 10 kDa and 25 kDa in denaturing and native conditions, respectively. LCaL injected by intravenous route in mice showed antinociceptive activity in the behavioral tests of Formalin and Writhing. In the formalin test LCaL inhibited the licking time by 37% in the neurogenic phase and by 73% in the inflammatory phase. In the acetic acid-induced writhing test LCaL showed inhibitory effect at 0.1 mg/kg (72%), 1 mg/kg (74%) and 10 mg/kg (70%). The lectin also inhibited the increase in vascular permeability at 10 mg/kg and leukocyte migration at 0.1, 1 and 10 mg/kg concentrations. Additionally, LCaL inhibited paw edema (mainly from 1 to 3 h by 46%) and hyperalgesia (1 h: 82%; 3 h: 63%) induced by carrageenan. In conclusion, LCaL presents an antinociceptive action mainly via inhibition of inflammation.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Fabaceae/química , Lectinas/isolamento & purificação , Nociceptividade/efeitos dos fármacos , Sementes/química , Animais , Hemaglutinação , Lectinas/química , Masculino , Camundongos , Peso Molecular
15.
Int J Biol Macromol ; 121: 643-649, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30339993

RESUMO

In this study, a new alkaloid was isolated from methanolic extract of Coccinea cordifolia root using flash chromatography and was subjected to spectral analysis like 1H NMR, 13C NMR, FTIR analysis and GCMS for confirming the structure of the isolated alkaloid. The isolated alkaloid was also subjected to immunomodulatory assays to verify its role in the claims against the plant. It was found that the isolated compound at a dose of 2.5 mg/kg has shown competitive immunomodulatory potential when evaluated by carbon clearance, delayed type hypersensitivity and haemagglutination titer models and using Levamisole at a dose of 50 mg/kg as the standard drug.


Assuntos
Alcaloides/farmacologia , Cucurbitaceae/química , Fatores Imunológicos/farmacologia , Raízes de Plantas/química , Alcaloides/isolamento & purificação , Animais , Adesão Celular/efeitos dos fármacos , Hemaglutinação/efeitos dos fármacos , Fatores Imunológicos/isolamento & purificação , Camundongos , Neutrófilos/citologia , Neutrófilos/efeitos dos fármacos
16.
Med Mycol ; 57(4): 510-514, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30212911

RESUMO

Trichosporon asahii is a human fungal pathogen that causes deep-seated infections in immunocompromised patients. While the pathogenic mechanisms of T. asahii remain unknown, our previous studies indicate that adherent colony morphologies were generated from parent strains, which may contribute to their pathogenicity. In the present study, we analyzed the hemolytic and hemagglutination activities of T. asahii. We report that T. asahii cells demonstrate hemagglutination and hemolytic activities, and that cell surface molecules play a role in the hemagglutination activity of adherent strains. These observations suggest that hemagglutination and hemolysis may be one of the pathogenic mechanisms of T. asahii.


Assuntos
Eritrócitos/microbiologia , Hemaglutinação , Hemólise , Interações Hospedeiro-Patógeno , Trichosporon/patogenicidade , Adesão Celular , Humanos , Trichosporon/fisiologia
17.
Virus Genes ; 55(1): 95-103, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30519855

RESUMO

Feline panleukopenia virus (FPV) infects cats and can be fatal to kittens. There is evidence that canine parvovirus originated from FPV, which makes FPV important in studies of the family Parvoviridae. In the present study, the entire genome of FPV strain HH-1/86 was converted into a full-length infectious clone (pFPV). The FPV strain HH-1/86 has a 5123-nt single stranded DNA genome with a Y-shaped inverted 3' terminal repeat (ITR) and a U-shaped inverted 5' ITR. Feline kidney cells (F81) were transfected with the pFPV clone which contained a genetic marker, and a rescued virus was obtained (rFPV). The rFPV was identified by its cytopathic effects, indirect immunofluorescence, growth curve analysis, western blot assay and hemagglutination, and was indistinguishable from the parent virus. The FPV infectious clone will facilitate the study of pathogenicity and viral replication of FPV and the inter-species transmission of parvoviruses.


Assuntos
Vírus da Panleucopenia Felina/genética , Panleucopenia Felina/virologia , Genética Reversa , Animais , Gatos , Clonagem Molecular , DNA Viral , Marcadores Genéticos , Genoma Viral , Genômica/métodos , Hemaglutinação , Hemaglutininas Virais/metabolismo , Genética Reversa/métodos , Sequenciamento Completo do Genoma
18.
Eur J Med Chem ; 163: 560-568, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30554131

RESUMO

It is urgently necessary to develop more effective anti-influenza agents due to the continuous emergence of drug-resistant strains of influenza virus. Our earlier studies have identified that certain pentacyclic triterpene derivatives are effective inhibitors of influenza virus infection. In the present study, a series of C-28 modified pentacyclic triterpene derivatives via conjugation with a series of polyphenols were synthesized, and their antiviral activities against influenza A/WSN/33 (H1N1) virus in MDCK (Madin-Darby canine kidney) cells were evaluated. Four compounds 23m, 23o, 23q and 23s displayed robust anti-influenza potency with averaged IC50 values at the low-micromole level, surpassing the potency of oseltamivir. In addition, the in vitro cytotoxic activity of the four conjugates against MDCK cells showed no toxicity at 100 µM. Further mechanism studies of compound 23s, one of the best representative conjugates with IC50 value of 5.80 µM and a selective index (SI) value of over 17.2, by hemagglutination inhibition (HI), surface plasmon resonance and molecular modeling indicated that this conjugate bound tightly to the viral envelope hemagglutinin (KD = 15.6 µM), thus blocking the invasion of influenza viruses into host cells.


Assuntos
Antivirais/síntese química , Triterpenos Pentacíclicos/farmacologia , Polifenóis/química , Animais , Antivirais/farmacologia , Cães , Hemaglutinação/efeitos dos fármacos , Humanos , Vírus da Influenza A Subtipo H1N1 , Concentração Inibidora 50 , Células Madin Darby de Rim Canino , Modelos Moleculares , Infecções por Orthomyxoviridae/tratamento farmacológico , Triterpenos Pentacíclicos/síntese química , Relação Estrutura-Atividade , Internalização do Vírus/efeitos dos fármacos
19.
Int J Biol Macromol ; 126: 291-297, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30583005

RESUMO

Lectins are carbohydrate-binding proteins broadly distributed in plants and have several biological functions, including antimicrobial action. Portulaca elatior is a Caatinga plant whose chemical composition and biotechnological potential have not been extensively studied. In this work, a lectin was isolated from P. elatior root extract and evaluated for antimicrobial activity. The P. elatior root lectin (PeRoL) showed native molecular mass of 33 kDa, pI 3.8 and is comprised of two subunits of 15 kDa linked by disulfide bonds. No sequence similarities with Viridiplantae proteins were observed. The PeRoL hemagglutinating activity (HA) was not affected by heating and was detected in a pH ranging from 4.0 to 8.0. Trehalose was identified as an endogenous inhibitor of PeRoL present in the roots. Bacteriostatic activity was detected against Enterococcus faecalis, Pseudomonas aeruginosa and Staphylococcus aureus (minimal inhibitory concentration of 8.1, 32.5 and 4.06 µg/mL, respectively). PeRoL induced the death of Candida albicans, Candida parapsilosis, Candida krusei, and Candida tropicalis cells, with a minimal fungicidal concentration of 16 µg/mL. The lectin (100 µg/mL) was not cytotoxic to human peripheral blood mononuclear cells (PBMCs) and did not show hemolytic activity. In conclusion, the roots of P. elatior contain a trehalose-binding, thermostable, and antimicrobial lectin.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Lectinas/farmacologia , Raízes de Plantas/química , Portulaca/química , Trealose/metabolismo , Sequência de Aminoácidos , Hemaglutinação/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Lectinas/isolamento & purificação , Peptídeos/química , Extratos Vegetais/farmacologia , Ligação Proteica
20.
Int J Biol Macromol ; 126: 170-178, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30584930

RESUMO

Colorectal cancer has an overexpression of galectin-3 that is related to cancer progression. A decreased risk of colon cancer can be related to consumption of dietary fibers, but the entire mechanism by which this protection occurs remains unclear. Pectin is a type of dietary fiber that possesses ß-galactosides and can bind and inhibit galectin-3-mediated effects. Papaya fruit has a massive cell wall disassembling during ripening that naturally changes its pectin structure. Our work shows that different points in the ripening time of papaya fruit exhibit pectins (chelate-soluble fractions; CSF) that can or cannot inhibit galectin-3. The fraction that inhibits galectin-3 (3CSF) also diminishes the proliferation of colon cancer cell lines, and it is derived from an intermediate point of papaya ripening. Therefore, we related this to a papaya pectin structure-dependent effect, and the papaya fruit seems to have a pectin structure that is promising in decreasing the risk of colon cancer development.


Assuntos
Carica/química , Quelantes/química , Neoplasias do Colo/patologia , Galectina 3/metabolismo , Pectinas/farmacologia , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Frutas/crescimento & desenvolvimento , Células HCT116 , Células HT29 , Hemaglutinação/efeitos dos fármacos , Humanos , Peso Molecular , Espectroscopia de Prótons por Ressonância Magnética , Coelhos , Solubilidade , Fatores de Tempo
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