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1.
Sci Total Environ ; 917: 170352, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38286293

ABSTRACT

The contamination of indoor areas is a global health problem that can cause the dispersion of infectious diseases. In that sense, it is urgent to find new strategies applying a lower concentration of the traditional chemicals used for cleaning and disinfection. Ultraviolet radiation (UV), in particular far-UV-C (200-225 nm), has emerged as a successful, powerful, easy-to-apply, and inexpensive approach for bacterial eradication that still requires scientific assessment. This study investigated new strategies for disinfection based on far-UV-C (222 nm) combined with chlorine and mechanical cleaning, providing an innovative solution using low doses. The bactericidal activity of far-UV-C (222 nm) was tested at an intensity of irradiation from 78.4 µW/cm2 to 597.7 µW/cm2 (for 1 min) against Escherichia coli and Staphylococcus epidermidis adhered on polystyrene microtiter plates. It was further tested in combination with mechanical cleaning (ultrasounds for 1 min) and free chlorine (0.1, 0.5, and 1 mg/L for 5 min). The triple combination consisting of mechanical cleaning + free chlorine (0.5 mg/L) + far-UV-C (54 mJ/cm2) was tested against cells adhered to materials found in hospital settings and other public spaces: polyvinyl chloride (PVC), stainless steel (SS), and polyetheretherketone (PEEK). Disinfection with far-UV-C (54 mJ/cm2) and free chlorine at 0.5 mg/L for 5 min allowed a total reduction of culturable E. coli cells and a logarithmic reduction of 2.98 ± 0.03 for S. epidermidis. The triple combination of far-UV-C, free chlorine, and mechanical cleaning resulted in a total reduction of culturable cells for both adhered bacteria. Bacterial adhesion to PVC, SS, and PEEK occurred at distinct extents and influenced the bactericidal activity of the triple combination, with logarithmic reductions of up to three. The overall results highlight that, based on culturability assessment, far-UV-C (54 mJ/cm2) with chlorine (0.5 mg/L; 5 min) and mechanical cleaning (1 min) as an efficient disinfection strategy using mild conditions. The combination of culturability and viability assessment of disinfection is recommended to detect regrowth events and increase the effectiveness in microbial growth control.


Subject(s)
Benzophenones , Escherichia coli , Polymers , Ultraviolet Rays , Staphylococcus epidermidis , Chlorine/pharmacology , Chlorine/chemistry , Disinfection/methods , Chlorides
2.
Biofouling ; 39(7): 691-705, 2023.
Article in English | MEDLINE | ID: mdl-37811587

ABSTRACT

The activity of two chlorinated isocyanurates (NaDCC and TCCA) and peroxymonosulphate (OXONE) was evaluated against biofilms of Stenotrophomonas maltophilia, an emerging pathogen isolated from drinking water (DW), and for the prevention of biofilm regrowth. After disinfection of pre-formed 48 h-old biofilms, the culturability was reduced up to 7 log, with OXONE, TCCA, and NaDCC showing more efficiency than free chlorine against biofilms formed on stainless steel. The regrowth of biofilms previously exposed to OXONE was reduced by 5 and 4 log CFU cm-2 in comparison to the unexposed biofilms and biofilms exposed to free chlorine, respectively. Rheometry analysis showed that biofilms presented properties of viscoelastic solid materials, regardless of the treatment. OXONE reduced the cohesiveness of the biofilm, given the significant decrease in the complex shear modulus (G*). AFM analysis revealed that biofilms had a fractured appearance and smaller bacterial aggregates dispersed throughout the surface after OXONE exposure than the control sample. In general, OXONE has been demonstrated to be a promising disinfectant to control DW biofilms, with a higher activity than chlorine. The results also show the impact of the biofilm mechanical properties on the efficacy of the disinfectants in biofilm control.


Subject(s)
Disinfectants , Drinking Water , Stenotrophomonas maltophilia , Chlorine/pharmacology , Biofilms , Disinfectants/pharmacology , Drinking Water/microbiology
3.
Braz J Med Biol Res ; 55: e12428, 2022.
Article in English | MEDLINE | ID: mdl-36383805

ABSTRACT

Gastroesophageal cancer (GEC) is an aggressive disease characterized by a high frequency of metastasis and poor overall survival rates. GEC presents HER2 overexpression in 5 to 25% of tumors eligible for HER2-targeted therapy. HER2 evaluation requires protein levels and copy number alteration analyses by immunohistochemistry (IHC) and in situ hybridization (FISH or SISH), respectively. These are semiquantitative methodologies that need an expert and well-trained pathologist. Therefore, the use of new surrogate methods for HER2 evaluation in cancer, such as gene expression analysis, might improve GEC HER2 classification. We evaluated HER2 positivity in GEC through conventional IHC and SISH analyses and investigated the potential application of HER2 mRNA expression by quantitative PCR to categorize GEC samples as HER2-positive or HER2-negative. Among 270 GEC samples, 10.9% were HER2-positive by IHC and SISH analyses. HER2 mRNA was overexpressed in HER2-positive GEC samples and presented high accuracy in distinguishing those tumors from HER2-negative GEC. Nevertheless, HER2 mRNA analysis was not capable of classifying HER2-equivocal GEC samples into HER2-positive or -negative according to SISH data. Quantitative PCR analysis showed HER2 overexpression in HER2-positive GEC samples. Nevertheless, HER2 mRNA analysis failed to classify HER2-equivocal GEC according to SISH data.


Subject(s)
Esophageal Neoplasms , Stomach Neoplasms , Humans , Receptor, ErbB-2/genetics , Stomach Neoplasms/metabolism , In Situ Hybridization , Esophageal Neoplasms/genetics , RNA, Messenger
4.
Braz. j. biol ; 82: e234476, 2022. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1153484

ABSTRACT

The Brazilian Cerrado biome consists of a great variety of endemic species with several bioactive compounds, and Anadenanthera peregrina (L.) Speg is a promising species. In this study, we aimed to perform phytochemical characterization and evaluate the antioxidant and antibacterial activities against Staphylococcus aureus and Escherichia coli of the hydroethanolic extract of A. peregrina stem bark. The barks were collected in the Botanical Garden of Goiânia, Brazil. The hydroethanolic extract was obtained by percolation and subjected to physicochemical screening, total phenolic content estimation, high-performance liquid chromatography (HPLC) fingerprinting, and antioxidant (IC50 values were calculated for the 2,2-diphenyl-1-picrylhydrazyl assay - DPPH) and antibacterial activity determination. The pH of the extract was 5.21 and density was 0.956 g/cm3. The phytochemical screening indicated the presence of cardiac glycosides, organic acids, reducing sugars, hemolytic saponins, phenols, coumarins, condensed tannins, flavonoids, catechins, depsides, and depsidones derived from benzoquinones. The extract showed intense hemolytic activity. The total phenolic content was 6.40 g GAE 100 g-1. The HPLC fingerprinting analysis revealed the presence of gallic acid, catechin, and epicatechin. We confirmed the antioxidant activity of the extract. Furthermore, the extract did not inhibit the growth of E. coli colonies at any volume tested, but there were halos around S. aureus colonies at all three volumes tested. These results contribute to a better understanding of the chemical composition of A. peregrina stem bark and further support the medicinal applications of this species.


O bioma Cerrado brasileiro apresenta em uma grande variedade de espécies endêmicas com diversos compostos bioativos, e Anadenanthera peregrina (L.) Speg é uma espécie promissora. Neste estudo, objetivamos realizar a caracterização fitoquímica e avaliar as atividades antioxidantes e antibacterianas contra Staphylococcus aureus e Escherichia coli do extrato hidroetanólico de cascas do caule de A. peregrina. As cascas foram coletadas no Jardim Botânico de Goiânia, Brasil. O extrato hidroetanólico foi obtido por percolação e submetido a triagem físicoquímica, estimativa de conteúdo fenólico total, impressão digital por cromatografia líquida de alta eficiência (HPLC) e determinação da atividade antioxidante (valores de IC50 foram calculados para o ensaio 2,2-difenil-1-picril-hidrazil) e antibacteriana. O pH do extrato foi de 5,21 e a densidade foi de 0,956 g/cm3. A triagem fitoquímica indicou a presença de glicosídeos cardíacos, ácidos orgânicos, açúcares redutores, saponinas hemolíticas, fenóis, cumarinas, taninos condensados, flavonóides, catequinas, depsídios e depsidonas derivados de benzoquinonas. O extrato mostrou intensa atividade hemolítica. O conteúdo fenólico total foi de 6,40 g de GAE 100 g-1. A análise por impressão digital por HPLC revelou a presença de ácido gálico, catequina e epicatequina. Confirmamos a atividade antioxidante do extrato. Além disso, o extrato não inibiu o crescimento de colônias de E. coli em nenhum volume testado, mas houve halos em torno das colônias de S. aureus nos três volumes testados. Estes resultados contribuem para uma melhor compreensão da composição química da casca de A. peregrina e apoia ainda mais as aplicações medicinais desta espécie.


Subject(s)
Plant Bark , Antioxidants/pharmacology , Staphylococcus aureus , Brazil , Plant Extracts/pharmacology , Escherichia coli , Phytochemicals , Anti-Bacterial Agents/pharmacology
5.
Braz. j. biol ; 82: 1-12, 2022. tab, ilus, graf
Article in English | LILACS, VETINDEX | ID: biblio-1468420

ABSTRACT

The Brazilian Cerrado biome consists of a great variety of endemic species with several bioactive compounds, and Anadenanthera peregrina (L.) Speg is a promising species. In this study, we aimed to perform phytochemical characterization and evaluate the antioxidant and antibacterial activities against Staphylococcus aureus and Escherichia coli of the hydroethanolic extract of A. peregrina stem bark. The barks were collected in the Botanical Garden of Goiânia, Brazil. The hydroethanolic extract was obtained by percolation and subjected to physicochemical screening, total phenolic content estimation, high-performance liquid chromatography (HPLC) fingerprinting, and antioxidant (IC50 values were calculated for the 2,2-diphenyl-1-picrylhydrazyl assay - DPPH) and antibacterial activity determination. The pH of the extract was 5.21 and density was 0.956 g/cm3. The phytochemical screening indicated the presence of cardiac glycosides, organic acids, reducing sugars, hemolytic saponins, phenols, coumarins, condensed tannins, flavonoids, catechins, depsides, and depsidones derived from benzoquinones. The extract showed intense hemolytic activity. The total phenolic content was 6.40 g GAE 100 g-¹. The HPLC fingerprinting analysis revealed the presence of gallic acid, catechin, and epicatechin. We confirmed the antioxidant activity of the extract. Furthermore, the extract did not inhibit the growth of E. coli colonies at any volume tested, but there were halos around S. aureus colonies at all three volumes tested. These results contribute to a better understanding of the chemical composition of A. peregrina stem bark and further support the medicinal applications of this species.


O bioma Cerrado brasileiro apresenta em uma grande variedade de espécies endêmicas com diversos compostos bioativos, e Anadenanthera peregrina (L.) Speg é uma espécie promissora. Neste estudo, objetivamos realizar a caracterização fitoquímica e avaliar as atividades antioxidantes e antibacterianas contra Staphylococcus aureus e Escherichia coli do extrato hidroetanólico de cascas do caule de A. peregrina. As cascas foram coletadas no Jardim Botânico de Goiânia, Brasil. O extrato hidroetanólico foi obtido por percolação e submetido a triagem físico química, estimativa de conteúdo fenólico total, impressão digital por cromatografia líquida de alta eficiência(HPLC) e determinação da atividade antioxidante (valores de IC50 foram calculados para o ensaio 2,2-difenil-1-picril-hidrazil) e antibacteriana. O pH do extrato foi de 5,21 e a densidade foi de 0,956 g/cm3. A triagem fitoquímica indicou a presença de glicosídeos cardíacos, ácidos orgânicos, açúcares redutores, saponinas hemolíticas, fenóis, cumarinas, taninos condensados, flavonóides, catequinas, depsídios e depsidonas derivados de benzoquinonas. O extrato mostrou intensa atividade hemolítica. O conteúdo fenólico total foi de 6,40 g de GAE 100 g-1. A análise por impressão digital por HPLC revelou a presença de ácido gálico, catequina e epicatequina. Confirmamos a atividade antioxidante do extrato. Além disso, o extrato não inibiu o crescimento de colônias de E. coli em nenhum volume testado, mas houve halos em torno das colônias de S. aureus nos três volumes testados. Estes resultados contribuem para uma melhor compreensão da composição química da casca de A. peregrina e apoia ainda mais as aplicações medicinais desta espécie.


Subject(s)
Plant Extracts/analysis , Plant Extracts/pharmacology , Fabaceae , Plants, Medicinal/chemistry
6.
Braz. j. biol ; 822022.
Article in English | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468607

ABSTRACT

Abstract The Brazilian Cerrado biome consists of a great variety of endemic species with several bioactive compounds, and Anadenanthera peregrina (L.) Speg is a promising species. In this study, we aimed to perform phytochemical characterization and evaluate the antioxidant and antibacterial activities against Staphylococcus aureus and Escherichia coli of the hydroethanolic extract of A. peregrina stem bark. The barks were collected in the Botanical Garden of Goiânia, Brazil. The hydroethanolic extract was obtained by percolation and subjected to physicochemical screening, total phenolic content estimation, high-performance liquid chromatography (HPLC) fingerprinting, and antioxidant (IC50 values were calculated for the 2,2-diphenyl-1-picrylhydrazyl assay - DPPH) and antibacterial activity determination. The pH of the extract was 5.21 and density was 0.956 g/cm3. The phytochemical screening indicated the presence of cardiac glycosides, organic acids, reducing sugars, hemolytic saponins, phenols, coumarins, condensed tannins, flavonoids, catechins, depsides, and depsidones derived from benzoquinones. The extract showed intense hemolytic activity. The total phenolic content was 6.40 g GAE 100 g-1. The HPLC fingerprinting analysis revealed the presence of gallic acid, catechin, and epicatechin. We confirmed the antioxidant activity of the extract. Furthermore, the extract did not inhibit the growth of E. coli colonies at any volume tested, but there were halos around S. aureus colonies at all three volumes tested. These results contribute to a better understanding of the chemical composition of A. peregrina stem bark and further support the medicinal applications of this species.


Resumo O bioma Cerrado brasileiro apresenta em uma grande variedade de espécies endêmicas com diversos compostos bioativos, e Anadenanthera peregrina (L.) Speg é uma espécie promissora. Neste estudo, objetivamos realizar a caracterização fitoquímica e avaliar as atividades antioxidantes e antibacterianas contra Staphylococcus aureus e Escherichia coli do extrato hidroetanólico de cascas do caule de A. peregrina. As cascas foram coletadas no Jardim Botânico de Goiânia, Brasil. O extrato hidroetanólico foi obtido por percolação e submetido a triagem físico-química, estimativa de conteúdo fenólico total, impressão digital por cromatografia líquida de alta eficiência (HPLC) e determinação da atividade antioxidante (valores de IC50 foram calculados para o ensaio 2,2-difenil-1-picril-hidrazil) e antibacteriana. O pH do extrato foi de 5,21 e a densidade foi de 0,956 g/cm3. A triagem fitoquímica indicou a presença de glicosídeos cardíacos, ácidos orgânicos, açúcares redutores, saponinas hemolíticas, fenóis, cumarinas, taninos condensados, flavonóides, catequinas, depsídios e depsidonas derivados de benzoquinonas. O extrato mostrou intensa atividade hemolítica. O conteúdo fenólico total foi de 6,40 g de GAE 100 g-1. A análise por impressão digital por HPLC revelou a presença de ácido gálico, catequina e epicatequina. Confirmamos a atividade antioxidante do extrato. Além disso, o extrato não inibiu o crescimento de colônias de E. coli em nenhum volume testado, mas houve halos em torno das colônias de S. aureus nos três volumes testados. Estes resultados contribuem para uma melhor compreensão da composição química da casca de A. peregrina e apoia ainda mais as aplicações medicinais desta espécie.

7.
Braz. j. med. biol. res ; 55: e12428, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1403914

ABSTRACT

Gastroesophageal cancer (GEC) is an aggressive disease characterized by a high frequency of metastasis and poor overall survival rates. GEC presents HER2 overexpression in 5 to 25% of tumors eligible for HER2-targeted therapy. HER2 evaluation requires protein levels and copy number alteration analyses by immunohistochemistry (IHC) and in situ hybridization (FISH or SISH), respectively. These are semiquantitative methodologies that need an expert and well-trained pathologist. Therefore, the use of new surrogate methods for HER2 evaluation in cancer, such as gene expression analysis, might improve GEC HER2 classification. We evaluated HER2 positivity in GEC through conventional IHC and SISH analyses and investigated the potential application of HER2 mRNA expression by quantitative PCR to categorize GEC samples as HER2-positive or HER2-negative. Among 270 GEC samples, 10.9% were HER2-positive by IHC and SISH analyses. HER2 mRNA was overexpressed in HER2-positive GEC samples and presented high accuracy in distinguishing those tumors from HER2-negative GEC. Nevertheless, HER2 mRNA analysis was not capable of classifying HER2-equivocal GEC samples into HER2-positive or -negative according to SISH data. Quantitative PCR analysis showed HER2 overexpression in HER2-positive GEC samples. Nevertheless, HER2 mRNA analysis failed to classify HER2-equivocal GEC according to SISH data.

8.
J Mater Chem B ; 9(20): 4211-4218, 2021 05 26.
Article in English | MEDLINE | ID: mdl-33998627

ABSTRACT

Rheumatoid arthritis (RA) is an autoimmune and chronic inflammatory disease characterized by joint inflammation. Since the inflammatory condition plays an important role in the disease process, it is important to develop and test new therapeutic approaches that specifically target and treat joint inflammation. In this study, a human 3D inflammatory cartilage-on-a-chip model was established to test the therapeutic efficacy of anti-TNFα mAb-CS/PAMAM dendrimer NPs loaded-Tyramine-Gellan Gum in the treatment of inflammation. The results showed that the proposed therapeutic approach applied to the human monocyte cell line (THP-1) and human chondrogenic primary cells (hCH) cell-based inflammation system revealed an anti-inflammatory capacity that increased over 14 days. It was also possible to observe that Coll type II was highly expressed by inflamed hCH upon the culture with anti-TNF α mAb-CS/PAMAM dendrimer NPs, indicating that the hCH cells were able maintain their biological function. The developed preclinical model allowed us to provide more robust data on the potential therapeutic effect of anti-TNF α mAb-CS/PAMAM dendrimer NPs loaded-Ty-GG hydrogel in a physiologically relevant model.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Antibodies, Monoclonal/therapeutic use , Biocompatible Materials/therapeutic use , Dendrimers/therapeutic use , Lab-On-A-Chip Devices , Tumor Necrosis Factor Inhibitors/therapeutic use , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Antibodies, Monoclonal/chemistry , Arthritis, Rheumatoid/drug therapy , Biocompatible Materials/chemical synthesis , Biocompatible Materials/chemistry , Cells, Cultured , Dendrimers/chemical synthesis , Dendrimers/chemistry , Humans , Hydrogels/chemistry , Inflammation/drug therapy , Nanoparticles/chemistry , Polysaccharides, Bacterial/chemistry , Tumor Necrosis Factor Inhibitors/chemical synthesis , Tumor Necrosis Factor Inhibitors/chemistry , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Tyramine/chemistry
9.
Braz J Biol ; 82: e234476, 2021.
Article in English | MEDLINE | ID: mdl-33681898

ABSTRACT

The Brazilian Cerrado biome consists of a great variety of endemic species with several bioactive compounds, and Anadenanthera peregrina (L.) Speg is a promising species. In this study, we aimed to perform phytochemical characterization and evaluate the antioxidant and antibacterial activities against Staphylococcus aureus and Escherichia coli of the hydroethanolic extract of A. peregrina stem bark. The barks were collected in the Botanical Garden of Goiânia, Brazil. The hydroethanolic extract was obtained by percolation and subjected to physicochemical screening, total phenolic content estimation, high-performance liquid chromatography (HPLC) fingerprinting, and antioxidant (IC50 values were calculated for the 2,2-diphenyl-1-picrylhydrazyl assay - DPPH) and antibacterial activity determination. The pH of the extract was 5.21 and density was 0.956 g/cm3. The phytochemical screening indicated the presence of cardiac glycosides, organic acids, reducing sugars, hemolytic saponins, phenols, coumarins, condensed tannins, flavonoids, catechins, depsides, and depsidones derived from benzoquinones. The extract showed intense hemolytic activity. The total phenolic content was 6.40 g GAE 100 g-1. The HPLC fingerprinting analysis revealed the presence of gallic acid, catechin, and epicatechin. We confirmed the antioxidant activity of the extract. Furthermore, the extract did not inhibit the growth of E. coli colonies at any volume tested, but there were halos around S. aureus colonies at all three volumes tested. These results contribute to a better understanding of the chemical composition of A. peregrina stem bark and further support the medicinal applications of this species.


Subject(s)
Antioxidants , Plant Bark , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Brazil , Escherichia coli , Phytochemicals , Plant Extracts/pharmacology , Staphylococcus aureus
10.
J Appl Microbiol ; 131(4): 1695-1709, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33714234

ABSTRACT

AIMS: To investigate the inhibitory activity and the distribution of biosynthetic genes encoding bovicin-like bacteriocins among ruminal Streptococcus isolated from beef and dairy cattle. METHODS AND RESULTS: Most isolates were classified as Streptococcus equinus and Streptococcus lutetiensis based on 16S rRNA sequencing. The antimicrobial activity of 150 ruminal streptococci isolated from beef and dairy cattle were tested by deferred inhibition assays and their genetic diversity was characterized by BOX-PCR. The frequency of biosynthetic genes associated with the biosynthesis of bovicin-like bacteriocins (bovicin HC5 and bovicin 255) was investigated by PCR screening. Approximately 33% of the ruminal streptococci isolated from Nellore heifers showed inhibitory activity in vitro with the majority harbouring genes for bacteriocin biosynthesis. In contrast, streptococci from Holstein cows showed limited inhibitory activity and a lower frequency of bacteriocin biosynthetic genes. CONCLUSIONS: Streptococcus from the rumen of beef and dairy cattle exhibit remarkable differences in inhibitory activity and distribution of genes associated with the biosynthesis of prototypical bovicins (bovicin HC5 and bovicin 255). SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings demonstrate that bovicin HC5 is distributed among ruminal streptococci from different breeds of cattle. The high degree of conservation of the bovicin HC5 structural gene among strains of ruminal streptococci suggests that random genetic drift is not a dominant force in the evolution of this bacteriocin.


Subject(s)
Bacteriocins , Animals , Bacteriocins/genetics , Cattle , Female , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics , Streptococcus/genetics , Streptococcus bovis
11.
Meat Sci ; 158: 107865, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31430643

ABSTRACT

Ninety-six Nellore bulls (430 ±â€¯13 kg and 24 months) were assigned to a completely randomized block design (2 × 2 factorial arrangement of treatments) to evaluate meat quality. Dietary treatments consisted of natural or exogenous contamination with mycotoxins (Factor 1), with or without yeast cell wall adsorbent (10 g/animal/d; Factor 2). The diets were provided during 97 d. The meat chemical composition was unaffected (P ≥ .37) by the factors and the averages of variables were 74.2% moisture, 22.7% protein, 1.04% ether extract, and 2.10% ash. The L*, a*, b*, E*, C* (P ≥ .11), cooking loss (P ≥ .24) and Warner-Bratzler shear force (P ≥ .17) were also similar among factors. In conclusion, low mycotoxin contamination and yeast cell wall based adsorbent do not affect meat quality of Nellore bulls finished in feedlot.


Subject(s)
Animal Feed/analysis , Mycotoxins/toxicity , Red Meat/standards , Animals , Cattle , Cell Wall/chemistry , Cooking , Diet/veterinary , Food Contamination , Male , Red Meat/analysis , Saccharomyces cerevisiae , Shear Strength
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 2466-2469, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31946397

ABSTRACT

The world's ageing population is rapidly increasing but people's healthspan is not being sustained. Activities of daily living and Montreal Cognitive Assessment scores from the first wave of a large nationally representative longitudinal study in ageing (TILDA) were analysed using multiple correspondence analysis, k-means clustering, network analysis and association rules mining, to find latent patterns in the data and categorise disability among older adults. It was observed that 6.2% of the population had a greater degree of frailty, specifically cognitive impairment. Additionally, the overall population showed difficulty in performing physically demanding activities. Thus, self-reported ADLs have a diagnostic importance as they indicate the level of cognitive and physical functional decline in the older population.


Subject(s)
Activities of Daily Living , Data Mining , Disabled Persons , Aged , Aging , Disabled Persons/classification , Humans , Longitudinal Studies
13.
Toxicol Res (Camb) ; 7(1): 102-116, 2018 Jan 01.
Article in English | MEDLINE | ID: mdl-30090567

ABSTRACT

Silver nanoparticles (AgNPs) are widely used in industrial and medical applications and humans may be exposed through different routes, increasing the risk of toxicity. We investigated the transcript expression of genes involved in the regulation of the hypothalamic-pituitary-testicular (HPT) axis and the parameters associated with sperm functionality after prepubertal exposure. AgNPs modulated the transcript expression of genes involved in the control of the HPT axis and spermatogenesis in the groups treated with lower doses, while the functional parameters related to sperm and puberty were affected in the groups administered higher doses. These results suggest that the HPT axis is disrupted by AgNPs during the prepubertal and pubertal periods, which are highly susceptible windows for the endocrine-disrupting chemical activity.

14.
Vet Parasitol ; 249: 70-73, 2018 Jan 15.
Article in English | MEDLINE | ID: mdl-29279089

ABSTRACT

Neospora caninum is one of the main agents that causes abortions in cattle worldwide. However, little is known about the pathogenesis of neosporosis in small ruminants, especially goats. Gerbils (Meriones unguiculatus) have been used as a model for neosporosis, and this species is highly susceptible to infection by bovine N. caninum strains. The present study aimed to evaluate the susceptibility of gerbils to a N. caninum isolate from goats. The placentas were obtained from naturally infected goats, that presented with mild to severe lymphoplasmacytic and histiocytic infiltrate, foci of necrosis, calcification and protozoan-like structures. Immunosuppressed gerbils bioassayed with N. caninum-infected placental tissues showed severe neurological signs. Microscopic lesions in these gerbils were characterized by encephalitis, myocarditis, myositis and pancreatitis. These lesions were often associated with a small to moderate number of N. caninum tachyzoites, confirmed by immunohistochemistry and PCR. This is the first report showing that goat N. caninum strains could infect immunocompetent gerbils and cause severe lesions and clinical signs in immunosuppressed gerbils.


Subject(s)
Biological Assay , Coccidiosis/parasitology , Coccidiosis/transmission , Gerbillinae/parasitology , Goat Diseases/parasitology , Neospora/physiology , Animals , Coccidiosis/immunology , Coccidiosis/pathology , Disease Models, Animal , Female , Gerbillinae/immunology , Goat Diseases/transmission , Goats , Immunohistochemistry , Neospora/genetics , Placenta/parasitology , Polymerase Chain Reaction , Pregnancy
15.
Article in English | MEDLINE | ID: mdl-25965513

ABSTRACT

In this work we present a study of the vibrational spectra of 4,5,6,8,9-pentachloropyrimido-[1,2-a][1,8]naphthyridin-10-one, C11H2Cl5N3O, a substance belonging to the important pharmacological class of 1,8-naphthyridine derivatives. The Fourier transform infrared and the Fourier transform Raman spectra of the crystal were recorded at room temperature in the regions 400-4000 and 50-4000 cm(-1), respectively. Vibrational wavenumbers were predicted using Density Functional Theory calculations with the B3LYP functional on 6-31G(d,p) and 6-311++G(d,p) basis sets. The descriptions of the normal modes were made after calculating the potential energy distribution. Additionally, potential reaction sites were evaluated through Mulliken population and Frontier Orbital analysis.


Subject(s)
Naphthyridines/chemistry , Pyrimidines/chemistry , Halogenation , Models, Molecular , Molecular Conformation , Quantum Theory , Spectroscopy, Fourier Transform Infrared , Spectrum Analysis, Raman
16.
Biochim Biophys Acta ; 1838(10): 2555-67, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24976292

ABSTRACT

Dioctadecyldimethylammonium bromide (DODAB):Monoolein (MO) lipoplexes have mainly been studied within the range of high molar ratios of DODAB, with noticeable transfection efficiencies in the Human Embryonic Kidney (HEK, a.k.a. 293T) cell line. In this work, we intend to study the effect of high MO content on the structure and physicochemical properties of pDNA/DODAB:MO lipoplexes to achieve some correlation with their transfection efficiency. Static/Dynamic Light Scattering and Cryo-TEM imaging were used to characterize the size/morphology of DNA/DODAB:MO lipoplexes at different DODAB:MO contents (2:1, 1:1, 1:2) and charge ratios (CRs) (+/-). Nile Red fluorescence emission was performed to detect changes in microviscosity, hydration and polarity of DNA/DODAB:MO systems. Lipoplexes stability at physiological pH values and in the presence of anionic lipids was evaluated by Förster Resonance Energy Transfer (FRET). Physicochemical/structural data were complemented with transfection studies in HEK cells using the ß-galactosidase reporter gene activity assay. This work reports the coexistence of multilamellar and non-lamellar inverted phases in MO-richer lipoplexes (DODAB:MO 1:2 and 1:4), leading to transfection efficiencies comparable to those of multilamellar (DODAB-richer) lipoplexes, but at higher charge ratios [CR (+/-)=6.0] and without dose-effect response. These results may be related to the structural changes of lipoplexes promoted by high MO content.


Subject(s)
DNA/chemistry , Glycerides/chemistry , Plasmids/chemistry , Quaternary Ammonium Compounds/chemistry , HEK293 Cells , Humans , Hydrogen-Ion Concentration , Transfection/methods
17.
Meat Sci ; 97(4): 602-8, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24795167

ABSTRACT

This study evaluated the effect of feed restriction and goat genotype on meat quality. Three genotypes (Brazilian native breed Canindé; Brazilian native breed Moxotó; and F1 Boer crossbred animals obtained by crossing Boer bucks with local breed does) and three different feeding regimens (ad libitum fed, AL; restricted fed at 75% of the ad libitum, R.75; or restricted fed at 50% of the average ad libitum intake, R.50) were used. There was no difference (P>0.05) in chemical composition, total and soluble collagen, and shear force of the Longissimus lumborum muscle among genotypes. However, AL had greater amounts of soluble collagen and crude protein in the muscle (P<0.05) than R.75. No difference (P>0.05) was observed for the myofibrillar fragmentation index. The goat genotype presented few differences in their fatty acid profiles. However, goats fed ad libitum had a more favorable fatty acid profile for human health with greater concentrations of oleic acid, unsaturated fatty acids, and conjugated linoleic acid.


Subject(s)
Collagen/analysis , Dietary Fats/analysis , Energy Intake , Fatty Acids, Unsaturated/analysis , Meat/analysis , Muscle Proteins/analysis , Muscle, Skeletal/chemistry , Animal Feed , Animals , Brazil , Breeding , Diet , Dietary Proteins/analysis , Goats/genetics , Humans , Meat/standards , Myofibrils , Stress, Mechanical
18.
Biomed Pharmacother ; 67(4): 329-35, 2013 May.
Article in English | MEDLINE | ID: mdl-23540282

ABSTRACT

Diphenyl diselenide (DPDS) is an electrophilic reagent used in the synthesis of a variety of pharmacologically active organoselenium compounds. Studies have shown its interesting pharmacodinamic properties, as antioxidant, antimutagenic and antitumoral effects. Here we report the antigenotoxic properties of DPDS against tamoxifen (TAM)-induced oxidative DNA damage in MCF-7 cultured cell line. We determined the cytotoxicity by lactate dehydrogenase (LDH) leakage assay and evaluated oxidative DNA damage by modified comet assay employing the enzymes formamidopyrimidine DNA-glycosylase (Fpg) and endonuclease III (Endo III). Our results demonstrate that the cellular effects of DPDS appear to be complex and concentration-dependent. The present findings show that DPDS is not genotoxic (at concentrations lower than 2.0µmol/L) in MCF-7 cells, as observed in the modified comet assay. Moreover, DPDS protects against TAM-induced oxidative DNA damage, probably by its antioxidant activity, without interfering with its cytotoxicity. In this manner, the treatment with low concentrations of DPDS, a synthetic organoselenium compound, could be used as a potent antigenotoxic agent to prevent the risk of cancer induction triggered by tamoxifen hormone therapy. Thereby, more studies concerning the toxicity of DPDS and its structural derivatives are still necessary for future safe therapeutic application and development of novel chemopreventive compounds for combined therapy in breast cancer.


Subject(s)
Antimutagenic Agents/pharmacology , Antineoplastic Agents, Hormonal/toxicity , Benzene Derivatives/pharmacology , Organoselenium Compounds/pharmacology , Tamoxifen/toxicity , Antimutagenic Agents/administration & dosage , Antimutagenic Agents/toxicity , Antioxidants/administration & dosage , Antioxidants/pharmacology , Antioxidants/toxicity , Benzene Derivatives/administration & dosage , Benzene Derivatives/toxicity , Breast Neoplasms/pathology , Comet Assay , DNA Damage/drug effects , Dose-Response Relationship, Drug , Female , Humans , MCF-7 Cells , Organoselenium Compounds/administration & dosage , Organoselenium Compounds/toxicity , Oxidative Stress/drug effects
19.
Toxicology ; 302(2-3): 197-202, 2012 Dec 16.
Article in English | MEDLINE | ID: mdl-22967792

ABSTRACT

Clothianidin (CLO) is a neonicotinoid insecticide with selective action on nicotinic acetylcholine receptors. The aim of this study was to determine the neurochemical basis for CLO-induced striatal dopamine release using the microdialysis technique in freely moving and conscious rats. Intrastriatal administration of CLO (3.5mM), produced an increase in both spontaneous (2462 ± 627% with respect to basal values) and KCl-evoked (4672 ± 706% with respect to basal values) dopamine release. This effect was attenuated in Ca(2+)-free medium, and was prevented in reserpine pre-treated animals or in presence of tetrodotoxin (TTX). To investigate the involvement of dopamine transporter (DAT), the effect of CLO was observed in presence of nomifensine. The coadministration of CLO and nomifensine produced an additive effect on striatal dopamine release. The results suggest that the effect of CLO on striatal dopamine release is predominantly mediated by an exocytotic mechanism, Ca(2+), vesicular and TTX-dependent and not by a mechanism mediated by dopamine transporter.


Subject(s)
Corpus Striatum/drug effects , Dopamine/metabolism , Guanidines/toxicity , Insecticides/toxicity , Thiazoles/toxicity , Animals , Calcium/metabolism , Corpus Striatum/metabolism , Dopamine Plasma Membrane Transport Proteins/drug effects , Exocytosis/drug effects , Female , Microdialysis/methods , Neonicotinoids , Nomifensine/toxicity , Rats , Rats, Sprague-Dawley , Receptors, Nicotinic/metabolism , Reserpine/pharmacology , Tetrodotoxin/pharmacology
20.
Ecotoxicol Environ Saf ; 72(5): 1565-71, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19232726

ABSTRACT

The purpose of the present work was to assess the effects of flutriafol, a triazole fungicide, on in vivo dopamine (DA) release from rat striatum, using brain microdialysis coupled to high-performance liquid chromatography with electrochemical detection (HPLC-EC). Intrastriatal administration of flutriafol (1, 6 and 12 mM) produced significant concentration-dependent increases in DA levels to 218.5+/-51%, 1376+/-245% and 3093+/-345% compared with basal values, respectively. Those increases in DA levels could be due to an increased DA exocytotic release and/or a change in the activity of DA transporter (DAT). Thus, we investigated the effects of flutriafol (6mM) under Ca(++)- or Na(+)-free conditions, and after pretreatment with reserpine and TTX. When flutriafol was perfused in either Ca(++)- or Na(+)-free Ringer, the DA levels reduced 92% and 70%, respectively; perfusion of flutriafol in TTX-treated (10 microM) or reserpine-pretreated animals (10mg/kg), reduced the levels of DA to 73% and 86%, respectively. Co-infusion of flutriafol and nomifensine (20 microM) shows that the flutriafol-induced DA release did not involve the DAT. Our results suggest that flutriafol induces DA release via vesicular-, Ca(++)-, Na(+)- and TTX-dependent mechanism, being independent of DAT.


Subject(s)
Basal Ganglia/drug effects , Dopamine/metabolism , Fungicides, Industrial/toxicity , Locomotion , Microdialysis , Triazoles/toxicity , Animals , Basal Ganglia/metabolism , Calcium/metabolism , Chromatography, High Pressure Liquid , Dopamine Plasma Membrane Transport Proteins/drug effects , Dopamine Plasma Membrane Transport Proteins/metabolism , Dopamine Uptake Inhibitors , Electrochemical Techniques , Exocytosis/drug effects , Female , Nomifensine/pharmacology , Potassium/metabolism , Rats , Rats, Sprague-Dawley , Reserpine/pharmacology , Sodium/metabolism , Sodium Channel Blockers/pharmacology , Tetrodotoxin/pharmacology , Time Factors
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