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1.
Int J Mol Sci ; 25(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38928478

RESUMO

Hereditary breast and ovarian cancer (HBOC) syndrome is a genetic condition that increases the risk of breast cancer by 80% and that of ovarian cancer by 40%. The most common pathogenic variants (PVs) causing HBOC occur in the BRCA1 gene, with more than 3850 reported mutations in the gene sequence. The prevalence of specific PVs in BRCA1 has increased across populations due to the effect of founder mutations. Therefore, when a founder mutation is identified, it becomes key to improving cancer risk characterization and effective screening protocols. The only founder mutation described in the Mexican population is the deletion of exons 9 to 12 of BRCA1 (BRCA1Δ9-12), and its description focuses on the gene sequence, but no transcription profiles have been generated for individuals who carry this gene. In this study, we describe the transcription profiles of cancer patients and healthy individuals who were heterozygous for PV BRCA1Δ9-12 by analyzing the differential expression of both alleles compared with the homozygous BRCA1 control group using RT-qPCR, and we describe the isoforms produced by the BRCA1 wild-type and BRCA1Δ9-12 alleles using nanopore long-sequencing. Using the Kruskal-Wallis test, our results showed a similar transcript expression of the wild-type allele between the healthy heterozygous group and the homozygous BRCA1 control group. An association between the recurrence and increased expression of both alleles in HBOC patients was also observed. An analysis of the sequences indicated four wild-type isoforms with diagnostic potential for discerning individuals who carry the PV BRCA1Δ9-12 and identifying which of them has developed cancer.


Assuntos
Alelos , Proteína BRCA1 , Síndrome Hereditária de Câncer de Mama e Ovário , Humanos , Proteína BRCA1/genética , Feminino , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Pessoa de Meia-Idade , Predisposição Genética para Doença , Adulto , Efeito Fundador , Éxons/genética , Neoplasias da Mama/genética , Heterozigoto , Mutação , México , Neoplasias Ovarianas/genética , Relevância Clínica
2.
Curr Microbiol ; 79(4): 99, 2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35150334

RESUMO

Mycotoxins may be present in nuts, coffee, cereals, and grapes, among other products. Increasing concerns about human health and environmental protection have driven the application of biological control techniques that can inhibit fungal contaminants. In this study, the growth inhibition of the ochratoxigenic fungus Aspergillus carbonarius Ac 162 was evaluated using 5 lactic acid bacteria (LAB). The LAB studied were Lactobacillus plantarum MZ801739 (J), Lactobacillus plantarum MZ809351 (31) and Lactobacillus plantarum MZ809350 (34), isolated in the Ivory Coast, and Lactobacillus plantarum MN982928 (3) and Leuconostoc citreum MZ801735 (23), isolated in Mexico. J, 31, 34, 3 and 23 are the internal strain codes from our laboratory. LAB were cultivated in De Man, Rogosa and Sharpe (MRS) broth, and different polyols (glycerol, mannitol, sorbitol, and xylitol) were added to the culture broth to stimulate the production of antifungal compounds. The fungal inhibition studies were performed using the poisoned food technique. The highest inhibition of A. carbonarius growth was obtained by cultivating L. plantarum MZ809351 in the presence of xylitol and glycerol. Under these conditions, 1 L of the L. plantarum MZ809351 cultures were used to identify antifungal compounds. The compounds were concentrated by solid-phase extraction and then characterized by GC-MS. In addition to 9-octadecenoic acid, 3 diketopiperazines or cyclic dipeptides were identified, including cyclo (Leu-Leu), cyclo (Pro-Gly) and cyclo (Val-Phe), which were compounds related to microbial antifungal activities. Xylitol and glycerol induced the production of these antifungal compounds against A. carbonarius Ac 162. On the other hand, adding xylitol and glycerol to the MRS broth reduced the Ochratoxin A (OTA) content to 56.8 and 54.7%, respectively. This study shows the potential for using L. plantarum MZ809351 as a biocontrol agent to prevent the growth of A. carbonarius and reduce the production of OTA in foods.


Assuntos
Lactobacillus plantarum , Micotoxinas , Antifúngicos/farmacologia , Humanos , Polímeros
3.
Extremophiles ; 25(3): 311-317, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33938983

RESUMO

Fucosylated oligosaccharides present in human milk perform various biological functions that benefit infants' health. These compounds can be also obtained by enzymatic synthesis. In this work, the effect of the immobilization of α-L-fucosidase from Thermotoga maritima on the synthesis of fucosylated oligosaccharides was studied, using lactose and 4-nitrophenyl-α-L-fucopyranoside (pNP-Fuc) as acceptor and donor substrates, respectively, and Eupergit® CM as an immobilization support. The enzyme was immobilized with 90% efficiency at pH 8 and ionic strength of 1.5 M. Immobilization decreased enzyme affinity for the donor substrate as shown by a 1.5-times higher KM value and a 22-times decrease of the kcat/KM ratio in comparison to the unbound enzyme. In contrast, no effect was observed on the synthesis/hydrolysis ratio (rs/rh) when α-L-fucosidase was immobilized. Also, the effect of initial concentration of substrates was studied. An increase of the acceptor concentration improved the yields of fucosylated oligosaccharides regardless enzyme immobilization. The synthesis yields of 38.9 and 40.6% were obtained using Eupergit® CM-bound or unbound enzyme, respectively, and 3.5 mM pNP-Fuc and 146 mM lactose. In conclusion, α-L-fucosidase from Thermotoga maritima was efficiently immobilized on Eupergit® CM support without affecting the synthesis of fucosylated oligosaccharides.


Assuntos
Thermotoga maritima , alfa-L-Fucosidase , Fucose , Oligossacarídeos , Especificidade por Substrato , Thermotoga , Thermotoga maritima/metabolismo , alfa-L-Fucosidase/metabolismo
4.
Rev Argent Microbiol ; 52(4): 305-314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31964562

RESUMO

The health benefits attributed to probiotics generate interest in the search of competent strains adapted to several ecological niches, especially those related to traditional beverages and foods of each country. Pineapple tepache, a traditional Mexican fermented beverage, was used for the isolation of lactic acid bacteria with probiotic potential, one of which withstood the in vitro tests. The isolated strain AB-05, which exhibited the tested probiotic functional properties, was designated as Lactobacillus pentosus ABHEAU-05. The sequence was registered in GenBank under access code MK587617. This study is the first report of a lactic acid bacterium with in vitro digestion resistance isolated from pineapple tepache. The survival of L. pentosus ABHEAU-05 in a symbiotic medium was proven using fermented milk enriched with inulin. The in vitro digestion-resistant probiotic activity of lactobacilli was measured through analysis of pH and proteolysis. Results showed that L. pentosus grew properly in fermented milk; therefore, this microorganism could be used in the manufacture of this kind of products. The concentration of L. pentosus reached up to 8.5logCFU/ml after 40h of fermentation. In addition, the production of peptides and the decrease in pH indicated the vigorous and active metabolic state of the lactic acid bacterium tested. The activity and the concentration of this microorganism were maintained during refrigeration. The results of this research conclude that L. plantarum ABHEAU-05 is an in vitro digestion-resistant microorganism that can be used as a starter culture for the production of functional foods of dairy origin.


Assuntos
Alimentos Fermentados , Lactobacillus pentosus , Probióticos , Bebidas , Digestão , Fermentação , Microbiologia de Alimentos , Ácido Láctico
5.
Biotechnol Appl Biochem ; 66(2): 172-191, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30508310

RESUMO

Fucosylated oligosaccharides play important physiological roles in humans, including in the immune response, transduction of signals, early embryogenesis and development, growth regulation, apoptosis, pathogen adhesion, and so on. Efforts have been made to synthesize fucosylated oligosaccharides, as it is difficult to purify them from their natural sources, such as human milk, epithelial tissue, blood, and so on. Within the strategies for its in vitro synthesis, it is remarkable the employment of fucosidases, enzymes that normally cleave the fucosyl residue from the non-reducing end of fucosylated compounds, as these enzymes are also capable of synthesizing them by means of a transfucosylation reaction. This review summarizes the progress in the use of fucosidases for the synthesis of compounds that have potential for industrial and commercial applications.


Assuntos
Fucose/química , Oligossacarídeos/síntese química , alfa-L-Fucosidase/química , Oligossacarídeos/química
6.
Molecules ; 24(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438557

RESUMO

Amaranthus hypochondriacus spp. is a commonly grown cereal in Latin America, known for its high protein content. The objective of this study was to separate and identify bioactive peptides found in amaranth seeds through enzymatically-assisted hydrolysis using alcalase and flavourzyme. Hydrolysis was carried out for each enzyme separately and compared to two-step continuous process where both enzymes were combined. The biological activity of the resulting three hydrolysates was analyzed, finding, in general, higher bioactive potential of the hydrolysate obtained in a continuous process (combined enzymes). Its fractions were separated by RP-HPLC, and their bioactivity was analyzed. In particular, two fractions showed the highest biological activity as ACE inhibitors with IC50 at 0.158 and 0.134, thrombin inhibitors with IC50 of 167 and 155, and antioxidants in ABTS assay with SC50 at 1.375 and 0.992 mg/L, respectively. Further sequence analysis of the bioactive peptides was carried out using MALDI-TOF, which identified amino acid chains that have not been reported as bioactive so far. Bibliographic survey allowed identification of similarities between peptides reported in amaranth and other proteins. In conclusion, amaranth proteins are a potential source of peptides with multifunctional activity.


Assuntos
Amaranthus/química , Peptídeos/química , Proteínas de Plantas/química , Sementes/química , Endopeptidases/metabolismo , Subtilisinas/metabolismo
7.
Molecules ; 24(13)2019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31261855

RESUMO

Fucosyl-oligosaccharides are natural prebiotics that promote the growth of probiotics in human gut and stimulate the innate immune system. In this work, the release of α-lfucosidase by Lactobacillus rhamnosus GG, and the use of this enzyme for the synthesis of fucosyl-oligosaccharides were investigated. Since α-lfucosidase is a membrane-bound enzyme, its release from the cells was induced by addition of 4-nitrophenyl-α-l-fucopyranoside (pNP-Fuc). Enzyme activity associated with the cell was recovered at 78% of its total activity. Fucosyl-oligosaccharides where synthesized using α-l-fucosidase extract and pNP-Fuc as donor substrate, and D-lactose or D-lactulose as acceptor substrates, reaching a yield up to 25%. Fucosyllactose was obtained as a reaction product with D-lactose, and its composition was confirmed by mass spectrometry (MALDI-TOF MS). It is possible that the fucosyl-oligosaccharide synthesized in this study has biological functions similar to human milk oligosaccharides.


Assuntos
Lacticaseibacillus rhamnosus/enzimologia , Oligossacarídeos/biossíntese , alfa-L-Fucosidase/isolamento & purificação , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Parede Celular/enzimologia , Cromatografia Líquida de Alta Pressão , Glicosídeos/química , Humanos , Espectrometria de Massas , Oligossacarídeos/química , Prebióticos , Especificidade por Substrato , alfa-L-Fucosidase/metabolismo
8.
Extremophiles ; 22(6): 889-894, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30088105

RESUMO

The influence of CaCl2 and NaCl in the hydrolytic activity and the influence of CaCl2 in the synthesis of fucosylated oligosaccharides using α-L-fucosidase from Thermotoga maritima were evaluated. The hydrolytic activity of α-L-fucosidase from Thermotoga maritima displayed a maximum increase of 67% in the presence of 0.8 M NaCl with water activity (aw) of 0.9672 and of 138% in the presence of 1.1 M CaCl2 (aw 0.9581). In addition, the hydrolytic activity was higher when using CaCl2 compared to NaCl at aw of 0.8956, 0.9581 and 0.9672. On the other hand, the effect of CaCl2 in the synthesis of fucosylated oligosaccharides using 4-nitrophenyl-fucose as donor substrate and lactose as acceptor was studied. In these reactions, the presence of 1.1 M CaCl2 favored the rate of transfucosylation, and improved the yield of synthesis duplicating and triplicating it with lactose concentrations of 58 and 146 mM, respectively. CaCl2 did not significatively affect hydrolysis rate in these reactions. The combination of the activating effect of CaCl2, the decrement in aw and lactose concentration had a synergistic effect favoring the synthesis of fucosylated oligosaccharides.


Assuntos
Proteínas de Bactérias/metabolismo , Oligossacarídeos/biossíntese , Thermotoga maritima/enzimologia , alfa-L-Fucosidase/metabolismo , Cálcio/metabolismo , Fucose/análogos & derivados , Sódio/metabolismo
9.
J Sci Food Agric ; 94(11): 2246-52, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24374769

RESUMO

BACKGROUND: Probiotics and prebiotics are among the most important functional food ingredients worldwide. The proven benefits of such ingredients to human health have encouraged the development of functional foods containing both probiotics and prebiotics. In this work, the production of antimicrobial compounds coupled to the uptake of commercial prebiotics by probiotic bacteria was investigated. RESULTS: The probiotic bacteria studied were able to take up commercial prebiotic carbohydrates to the same or higher extent than that observed for lactose (control carbohydrate). The growth of probiotic bacteria was coupled to the production of antimicrobials such as short-chain fatty acids (SCFA), H2 O2 and bacteriocins. A higher production of antimicrobial compounds was recorded with Oligomate 55® compared with Regulact® and Frutafit® (3-5 and 10-115 times higher SCFA and H2 O2 production, respectively). The probiotic bacteria grown with Oligomate 55® also produced bacteriocins and other non-identified antimicrobial compounds. The antimicrobials produced by the probiotic bacteria inhibited up to 50% the growth of model pathogens such as Escherichia coli, Listeria innocua and Micrococcus luteus compared with control cultures. CONCLUSIONS: The results here obtained are useful for the adequate selection of probiotic/prebiotics pairs and therefore in the development of efficient functional foods.


Assuntos
Anti-Infecciosos/farmacologia , Bacteriocinas/biossíntese , Ácidos Graxos Voláteis/biossíntese , Peróxido de Hidrogênio/metabolismo , Lactobacillus/metabolismo , Prebióticos , Probióticos/metabolismo , Antibiose , Bacteriocinas/farmacologia , Comércio , Carboidratos da Dieta/metabolismo , Escherichia coli/efeitos dos fármacos , Ácidos Graxos Voláteis/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia , Listeria/efeitos dos fármacos , Micrococcus/efeitos dos fármacos , Simbióticos
10.
Rev Argent Microbiol ; 46(1): 58-65, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-24721277

RESUMO

There is a great variety of fermented milks containing lactic acid bacteria that present health-promoting properties. Milk proteins are hydrolyzed by the proteolytic system of these microorganisms producing peptides which may also perform other functions in vivo. These peptides are encrypted within the primary structure of proteins and can be released through food processing, either by milk fermentation or enzymatic hydrolysis during gastrointestinal transit. They perform different activities, since they act in the cardiovascular, digestive, endocrine, immune and nervous systems. Bioactive peptides that have an antihypertensive, antithrombotic, antioxidant and hypocholesterolemic effect on the cardiovascular system can reduce the risk factors for chronic disease manifestation and help improve human health. Most studied bioactive peptides are those which exert an antihypertensive effect by inhibiting the angiotensin-converting enzyme (ACE). Recently, the study of these peptides has focused on the implementation of tests to prove that they have an effect on health. This paper focuses on the production of ACEinhibitory antihypertensive peptides from fermented milks, its history, production and in vivo tests on rats and humans, on which its hypotensive effect has been shown.


Assuntos
Produtos Fermentados do Leite , Hipertensão/dietoterapia , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Animais , Bifidobacterium/enzimologia , Bovinos , Produtos Fermentados do Leite/enzimologia , Produtos Fermentados do Leite/microbiologia , Humanos , Lactobacillus/enzimologia , Lactococcus/enzimologia , Proteínas do Leite/metabolismo , Peptídeos/farmacocinética , Peptídeos/farmacologia , Ratos , Streptococcus/enzimologia
11.
Front Microbiol ; 14: 1160073, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168112

RESUMO

Background: Non-typeable Haemophilus influenzae has become increasingly important as a causative agent of invasive diseases following vaccination against H. influenzae type b. The emergence of antibiotic resistance underscores the necessity to investigate typeable non-b carriage and non-typeable H. influenzae (NTHi) in children. Methods: Nasopharyngeal swab samples were taken over a three-year period (2016-2018) from 336 children (6-30 months of age) attending daycare centers (DCCs) in Belgium, and from 218 children with acute otitis media (AOM). Biotype, serotype, and antibiotic resistance of H. influenzae strains were determined phenotypically. Mutations in the ftsI gene were explored in 129 strains that were resistant or had reduced susceptibility to beta-lactam antibiotics. Results were compared with data obtained during overlapping time periods from 94 children experiencing invasive disease. Results: Overall, NTHi was most frequently present in both carriage (DCC, AOM) and invasive group. This was followed by serotype "f" (2.2%) and "e" (1.4%) in carriage, and "b" (16.0%), "f" (11.7%), and "a" (4.3%) in invasive strains. Biotype II was most prevalent in all studied groups, followed by biotype III in carriage and I in invasive strains. Strains from both groups showed highest resistance to ampicillin (26.7% in carriage vs. 18.1% in invasive group). A higher frequency of ftsI mutations were found in the AOM group than the DCC group (21.6 vs. 14.9% - p = 0.056). Even more so, the proportion of biotype III strains that carried a ftsI mutation was higher in AOM compared to DCC (50.0 vs. 26.3% - p < 0.01) and invasive group. Conclusion: In both groups, NTHi was most frequently circulating, while specific encapsulated serotypes for carriage and invasive group were found. Biotypes I, II and III were more frequently present in the carriage and invasive group. The carriage group had a higher resistance-frequency to the analyzed antibiotics than the invasive group. Interestingly, a higher degree of ftsI mutations was found in children with AOM compared to DCC and invasive group. This data helps understanding the H. influenzae carriage in Belgian children, as such information is scarce.

12.
Sci Rep ; 12(1): 9, 2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34997050

RESUMO

Non-pathogenic Neisseria are a reservoir of antimicrobial resistance genes for pathogenic Neisseria meningitidis and Neisseria gonorrhoeae. Men who have sex with men (MSM) are at risk of co-colonization with resistant non-pathogenic and pathogenic Neisseria. We assessed if the antimicrobial susceptibility of non-pathogenic Neisseria among MSM differs from a general population and if antimicrobial exposure impacts susceptibility. We recruited 96 participants at our center in Belgium: 32 employees, 32 MSM who did not use antibiotics in the previous 6 months, and 32 MSM who did. Oropharyngeal Neisseria were cultured and identified with MALDI-TOF-MS. Minimum inhibitory concentrations for azithromycin, ceftriaxone and ciprofloxacin were determined using E-tests® and compared between groups with non-parametric tests. Non-pathogenic Neisseria from employees as well as MSM were remarkably resistant. Those from MSM were significantly less susceptible than employees to azithromycin and ciprofloxacin (p < 0.0001, p < 0.001), but not ceftriaxone (p = 0.3). Susceptibility did not differ significantly according to recent antimicrobial exposure in MSM. Surveilling antimicrobial susceptibility of non-pathogenic Neisseria may be a sensitive way to assess impact of antimicrobial exposure in a population. The high levels of antimicrobial resistance in this survey indicate that novel resistance determinants may be readily available for future transfer from non-pathogenic to pathogenic Neisseria.


Assuntos
Antibacterianos/farmacologia , Neisseria/efeitos dos fármacos , Orofaringe/microbiologia , Bélgica , Ciprofloxacina/farmacologia , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Neisseria/classificação , Neisseria/genética , Neisseria/isolamento & purificação , Penicilinas/farmacologia , Tetraciclina/farmacologia
13.
Nat Prod Res ; 36(13): 3485-3488, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33356582

RESUMO

Amaranth is a protein-rich seed, highly consumed in Mexico and reported as a potential source of bio-peptides with physiological function. Therefore, the objective of this study was to evaluate and identify bioactive peptide sequences from amaranth protein fractions released by pepsin and pancreatin in vitro digestion. Multifunctional bioactivities of peptides were measured through antihypertensive, antithrombotic and antioxidant assays. Peptide sequences were identified by analysis with a Nano-LC-ESI-MS/MS. With these results, it was demonstrated that the in vitro enzymatic digestion mechanism allows the release of multifunctional bioactive peptide fractions from amaranth proteins.


Assuntos
Amaranthus , Digestão , Peptídeos/farmacologia , Proteínas de Plantas , Espectrometria de Massas em Tandem
14.
Anaerobe ; 17(6): 267-72, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21497665

RESUMO

Coffee contamination by ochratoxigenic fungi affects both coffee quality as well as coffee price with harmful consequences on the economy of the coffee exporting countries for whom which is their main source of income. Fungal strains were isolated from coffee beans and identified as black Aspergilli. Ochratoxigenic moulds like Aspergillus carbonarius were screened and selected for detailed studies. Also lactic acid bacteria (LAB) were isolated from silage coffee pulp and their antifungal activity was tested on dual-culture agar plate. Ten of the isolated LAB demonstrated antifungal effect against A. carbonarius. API 50 CH and APIZYM were used to perform phenotypic identification. 16S rDNA sequencing was made to confirm the results.


Assuntos
Aspergillus/crescimento & desenvolvimento , Coffea/microbiologia , Lactobacillus plantarum/fisiologia , Interações Microbianas , Aspergillus/isolamento & purificação , Técnicas de Tipagem Bacteriana , Metabolismo dos Carboidratos , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Enzimas/metabolismo , Lactobacillus plantarum/classificação , Lactobacillus plantarum/isolamento & purificação , Lactobacillus plantarum/metabolismo , RNA Ribossômico 16S/genética , Sementes/microbiologia , Análise de Sequência de DNA
15.
Appl Biochem Biotechnol ; 193(11): 3553-3569, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34312785

RESUMO

The effects of water activity (aw), pH, and temperature on transglycosylation activity of α-L-fucosidase from Thermotoga maritima in the synthesis of fucosylated oligosaccharides were evaluated using different water-organic cosolvent reaction systems. The optimum conditions of transglycosylation reaction were the pH range between 7 and 10 and temperature 90-95 °C. The addition of organic cosolvent decreased α-L-fucosidase transglycosylation activity in the following order: acetone > dimethyl sulfoxide (DMSO) > acetonitrile (0.51 > 0.42 > 0.18 mM/h). However, the presence of DMSO and acetone enhanced enzyme-catalyzed transglycosylation over hydrolysis as demonstrated by the obtained transglycosylation/hydrolysis rate (rT/H) values of 1.21 and 1.43, respectively. The lowest rT/H was calculated for acetonitrile (0.59), though all cosolvents tested improved the transglycosylation rate in comparison to a control assay (0.39). Overall, the study allowed the production of fucosylated oligosaccharides in water-organic cosolvent reaction media using α-L-fucosidase from T. maritima as biocatalyst.


Assuntos
Proteínas de Bactérias/química , Fucose/química , Oligossacarídeos/síntese química , Thermotoga maritima/enzimologia , alfa-L-Fucosidase/química , Solventes/química , Água/química
16.
Infant Ment Health J ; 31(5): 521-542, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28543838

RESUMO

A pilot intervention that emphasized training and technical assistance to promote warm, sensitive, and responsive one-on-one caregiver-child interactions primarily during feeding and bathing/changing was implemented using regular staff in a depressed orphanage for children birth to approximately 8 years of age in Latin America. Despite a variety of unanticipated irregularities in the implementation of the intervention, many beyond the researchers' control, ward environments improved; caregivers displayed more warm, sensitive, and responsive interactions with children; and children improved an average of 13.5 developmental quotient (DQ) points after 4+ months' exposure to the completed intervention. Furthermore, 82% of the children had DQs greater than 70 before the intervention, but only 27.8% did so afterward. Although the training for all caregivers was aimed at children birth to 3 years, the number of different caregivers was reduced, and technical assistance was provided only to caregivers serving children less than 3 years, younger and older children (3-8 years) improved approximately the same amount. However, children who were transitioned from a younger to an older ward during the intervention improved less than did children who remained in either a younger or an older ward, the first evidence suggesting that the common orphanage practice of periodically graduating children from one homogeneous age group to another may impede their development. The study is consistent with others that have shown that orphanages can be changed, and increases primarily in warm, sensitive, responsive caregiver-child interactions can produce improvements in children's development.

17.
Front Med (Lausanne) ; 7: 225, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32574326

RESUMO

Introduction: COVID-19 Ag Respi-Strip, an immunochromatographic (ICT) assay for the rapid detection of SARS-CoV-2 antigen on nasopharyngeal specimen, has been developed to identify positive COVID-19 patients allowing prompt clinical and quarantine decisions. In this original research article, we describe the conception, the analytical and clinical performances as well as the risk management of implementing the COVID-19 Ag Respi-Strip in a diagnostic decision algorithm. Materials and Methods: Development of the COVID-19 Ag Respi-Strip resulted in a ready-to-use ICT assay based on a membrane technology with colloidal gold nanoparticles using monoclonal antibodies directed against the SARS-CoV and SARS-CoV-2 highly conserved nucleoprotein antigen. Four hundred observations were recorded for the analytical performance study and thirty tests were analyzed for the cross-reactivity study. The clinical performance study was performed in a retrospective multi-centric evaluation on aliquots of 328 nasopharyngeal samples. COVID-19 Ag Respi-Strip results were compared with qRT-PCR as golden standard for COVID-19 diagnostics. Results: In the analytical performance study, the reproducibility showed a between-observer disagreement of 1.7%, a robustness of 98%, an overall satisfying user friendliness and no cross-reactivity with other virus-infected nasopharyngeal samples. In the clinical performance study performed in three different clinical laboratories during the ascendant phase of the epidemiological curve, we found an overall sensitivity and specificity of 57.6 and 99.5%, respectively with an accuracy of 82.6%. The cut-off of the ICT was found at CT <22. User-friendliness analysis and risk management assessment through Ishikawa diagram demonstrate that COVID-19 Ag Respi-Strip may be implemented in clinical laboratories according to biosafety recommendations. Conclusion: The COVID-19 Ag Respi-Strip represents a promising rapid SARS-CoV-2 antigen assay for the first-line diagnosis of COVID-19 in 15 min at the peak of the pandemic. Its role in the proposed diagnostic algorithm is complementary to the currently-used molecular techniques.

18.
J Photochem Photobiol B ; 209: 111957, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32682284

RESUMO

Since the high incidence of aflatoxin M1 (AFM1) in milk and dairy products poses a serious risk to human health, this work aimed to investigate the complex formation between bovine α-lactalbumin (α-La) and AFM1 using different spectroscopic methods coupled with molecular docking studies. Fluorescence spectroscopy measurements demonstrated the AFM1 addition considerably reduced the α-La fluorescence intensity through a static quenching mechanism. The results indicated on the endothermic character of the reaction, and the hydrophobic interaction played a major role in the binding between AFM1 and α-La. The binding site stoichiometric value (n = 1.32) and a binding constant of 2.12 × 103 M-1 were calculated according to the Stern-Volmer equation. The thermodynamic parameters ΔH, ΔS and ΔGb were determined at 93.58 kJ mol-1, 0.378 kJ mol-1 K-1 and -19.17 ±â€¯0.96 kJ mol-1, respectively. In addition, far-UV circular dichroism studies revealed alterations in the α-La secondary structures when the α-La-AFM1 complex was formed. An increased content of the α-helix structures (from 35 to 40%) and the ß-sheets (from 16 to 19%) were observed. Furthermore, protein-ligand docking modelling demonstrated AFM1 could bind to the hydrophobic regions of α-La protein. Overall, the gathered results confirmed the α-La-AFM1 complex formation.


Assuntos
Aflatoxina M1/química , Contaminação de Alimentos/análise , Lactalbumina/química , Animais , Sítios de Ligação , Bovinos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Leite/química , Simulação de Acoplamento Molecular , Estrutura Secundária de Proteína , Soroalbumina Bovina/química , Termodinâmica
19.
JMIR Res Protoc ; 8(12): e14339, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31833834

RESUMO

BACKGROUND: Among Latinas and Hispanics (henceforth referred to as Latinas), breast cancer is the most commonly diagnosed cancer and the leading cause of cancer-related deaths. However, few interventions have been developed to meet the needs of Latina women undergoing active treatment for breast cancer. OBJECTIVE: This paper aims to describe the procedures and methods of My Guide for Breast Cancer Treatment and the plans for conducting a multisite randomized controlled trial to investigate the feasibility and preliminary efficacy of this smartphone-based app for Latina women in active treatment for breast cancer. METHODS: Study participants will be randomized to the My Guide for Breast Cancer Treatment intervention or the enhanced usual care control condition for 12 weeks. Participants will have access to innovative features such as gamification via virtual awards to reinforce usage and an adaptive section that presents targeted material based on their self-reported concerns and needs. Using a stepped-care approach, intervention participants will also receive telecoaching to enhance their adherence to the app. Study outcomes and intervention targets will be measured at study enrollment (before randomization), 6 and 12 weeks after initial app use. General and disease-specific health-related quality of life (HRQoL) and symptom burden are the study's primary outcomes, whereas anxiety, depression, fear of cancer recurrence, physical activity, and dietary intake are secondary outcomes. RESULTS: Recruitment began in August 2019 and is expected to be completed by August 2020. We expect to submit study results for publication by fall 2020. CONCLUSIONS: My Guide for Breast Cancer Treatment has the potential to improve HRQoL and reduce symptom burden, and increase access to supportive care resources among Latina breast cancer patients. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/14339.

20.
Front Public Health ; 7: 150, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31275914

RESUMO

Infectious diseases remain a serious public health concern globally, while the need for reliable and representative surveillance systems remains as acute as ever. The public health surveillance of infectious diseases uses reported positive results from sentinel clinical laboratories or laboratory networks, to survey the presence of specific microbial agents known to constitute a threat to public health in a given population. This monitoring activity is commonly based on a representative fraction of the microbiology laboratories nationally reporting to a single central reference point. However, in recent years a number of clinical microbiology laboratories (CML) have undergone a process of consolidation involving a shift toward laboratory amalgamation and closer real-time informational linkage. This report aims to investigate whether such merging activities might have a potential impact on infectious diseases surveillance. Influenza data was used from Belgian public health surveillance 2014-2017, to evaluate whether national infection trends could be estimated equally as effectively from only just one centralized CML serving the wider Brussels area (LHUB-ULB). The overall comparison reveals that there is a close correlation and representativeness of the LHUB-ULB data to the national and international data for the same time periods, both on epidemiological and molecular grounds. Notably, the effectiveness of the LHUB-ULB surveillance remains partially subject to local regional variations. A subset of the Influenza samples had their whole genome sequenced so that the observed epidemiological trends could be correlated to molecular observations from the same period, as an added-value proposition. These results illustrate that the real-time integration of high-throughput whole genome sequencing platforms available in consolidated CMLs into the public health surveillance system is not only credible but also advantageous to use for future surveillance and prediction purposes. This can be most effective when implemented for automatic detection systems that might include multiple layers of information and timely implementation of control strategies.

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