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1.
Biomolecules ; 12(3)2022 02 28.
Article in English | MEDLINE | ID: mdl-35327575

ABSTRACT

Fish bones are a natural calcium phosphate (CaP) sources used in biomaterials production for bone regeneration. CaP scaffolds can be enriched with other substances with biological activity to improve bone repair. This study aimed to evaluate the physicochemical properties and bone regeneration potential of biphasic calcium phosphate (BCP) scaffolds impregnated with free curcumin (BCP-CL) or complexed with ß-cyclodextrin (BCP-CD) compared to BCP scaffolds. Rietveld's refinement showed that BCP is composed of 57.2% of HAp and 42.8% of ß-TCP and the molar ratio of Ca/P corresponds to 1.59. The scaffolds presented porosity (macro and microporosity) of 57.21%. Apatite formation occurred on the BCP, BCP-CL, and BCP-CD surface, in vitro, in SBF. Micro-Raman technique showed a reduction in the dissolution rate of ß-TCP in the curcumin-impregnated scaffolds over time, and in vivo studies on critical-size defects, in rat calvaria, had no additional regenerative effect of BCP-CL and BCP-CD scaffolds, compared to BCP scaffolds. Despite this, the study showed that curcumin impregnation in BCP scaffolds prolongs the release of the ß-TCP phase, the BCP- phase with the higher osteoinductive potential, representing an advantage in tissue engineering.


Subject(s)
Curcumin , beta-Cyclodextrins , Animals , Bone Regeneration , Curcumin/pharmacology , Hydroxyapatites , Rats , Tissue Scaffolds/chemistry , beta-Cyclodextrins/pharmacology
2.
J Biomol Struct Dyn ; 40(20): 10136-10152, 2022.
Article in English | MEDLINE | ID: mdl-34155952

ABSTRACT

Pertussis is a highly contagious respiratory disease caused by Bordetella pertussis, a Gram-negative bacterium described over a century ago. Despite broad vaccine coverage and treatment options, the disease is remerging as a public health problem especially in infants and older children. Recent data indicate re-emergence of the disease is related to bacterial resistance to immune defences and decreased vaccine effectiveness, which obviously suggests the need of new effective vaccines and drugs. In an attempt to contribute with solutions to this great challenge, bioinformatics tools were used to genetically comprehend the species of these bacteria and predict new vaccines and drug targets. In fact, approaches were used to analysis genomic plasticity, gene synteny and species similarities between the 20 genomes of Bordetella pertussis already available. Furthermore, it was conducted reverse vaccinology and docking analysis to identify proteins with potential to become vaccine and drug targets, respectively. The analyses showed the 20 genomes belongs to a homogeneous group that has preserved most of the genes over time. Besides that, were found genomics islands and good proteins to be candidates for vaccine and drugs. Taken together, these results suggests new possibilities that may be useful to develop new vaccines and drugs that will help the prevention and treatment strategies of pertussis disease caused by these Bordetella strains. Communicated by Ramaswamy H. Sarma.


Subject(s)
Bordetella pertussis , Whooping Cough , Child , Humans , Adolescent , Bordetella pertussis/genetics , Whooping Cough/prevention & control , Whooping Cough/microbiology , Pertussis Vaccine/pharmacology , Genomics
3.
Acta Trop ; 174: 158-164, 2017 Oct.
Article in English | MEDLINE | ID: mdl-27080332

ABSTRACT

Toxocara canis, Toxocara cati, are roundworms that live in the intestines of dogs and cats, respectively, and are predominantly agents of human toxocariasis. Studies have suggested that Toxocara spp. seroprevalence increases levels of total and aeroallergen-specific IgE (sIgE), asthma prevalence and asthma morbidity. Nevertheless, other work reported a negative association between Toxocara spp. seropositivity with skin hypersensititity and a positive association with sIgE. The objective of the present study was to evaluate risk factors for acquiring Toxocara spp. infection and to investigate possible significant association between its seroprevalence with atopy and asthma. Students from elementary schools, residents in a small town and its surroundings of Northeast Brazil, underwent blood sampling to measure levels of anti-Toxocara spp. IgG, peripheral blood eosinophils, and specific IgE to aeroallergens. We used univariable and multivariable logistic regression analyses to assess possible risk factors for Toxocara spp. seropositivity and its association with atopy, wheeze/asthma with asthma phenotypes, in a sample of 791 elementary school children aged 6-13 years. Toxocara spp. seroprevalence reached 63.6%; 49.9% had sIgE; 7.2% and 3.3% had atopic wheeze/asthma and non-atopic wheeze/asthma respectively. Risk factors associated with Toxocara spp. seropositivity were: contact with dogs (adj. OR 2.33; 95% CI=1.70-3.19) and cats (adj. OR 3.09; 95% CI=2.10-4.55), and male sex (adj. OR 2.21; 95% CI=1.62-3.02). The presence of anti-Toxocara IgG was statistically associated with blood eosinophils >4% and >10% (adj. OR 1.84; 95% CI=1.33-2.55 and adj. OR 2.07; 95% CI=1.45-2.97, respectively), and atopy (adj. OR 2.00; 95% CI=1.49-2.68), but it was not associated with wheeze/asthma. Concluding, the results obtained in this study showing the association of Toxocara spp. seroprevalence with sIgE may suggest a possible immunological cross-reactivity between IgE epitopes from Toxocara spp. and aeroallergens.


Subject(s)
Antibodies, Helminth/blood , Asthma/epidemiology , Hypersensitivity, Immediate/epidemiology , Toxocara/isolation & purification , Toxocariasis/epidemiology , Toxocariasis/immunology , Adolescent , Animals , Brazil/epidemiology , Cats , Child , Dogs , Female , Humans , Male , Prevalence , Risk Factors , Rural Population/statistics & numerical data , Schools/statistics & numerical data , Seroepidemiologic Studies , Students/statistics & numerical data
4.
Data Brief ; 9: 425-428, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27699195

ABSTRACT

In the present article, we provide shortly, data on risk factors for acquiring Toxocara spp. infection and investigate possible associations between this infection with atopy and asthma in school children of a small town and its semi-rural areas of Northeast Brazil. The data set are composed by demographic, social and home environment variables. The detection of anti-Toxocara spp. IgG and specific IgE to aeroallergens was determined by ELISA and ImmunocAP/Phadiatrope systems, respectively. The data presented in this article are related to the article entitled "Risk factors for Toxocara spp. seroprevalence and its association with atopy and asthma phenotypes in school-age children in a small town and semi-rural areas of Northeast Brazil" (M.B. Silva, A.L. Amor, L.N. Santos, A.A. Galvão, A.V. Oviedo Vera, E.S. Silva et al., 2016) [1].

5.
Acta Trop ; 159: 132-41, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27038556

ABSTRACT

Infection with helminthic parasites, including the soil-transmitted helminth Trichuris trichiura (human whipworm), has been shown to modulate host immune responses and, consequently, to have an impact on the development and manifestation of chronic human inflammatory diseases. De novo derivation of helminth proteomes from sequencing of transcriptomes will provide valuable data to aid identification of parasite proteins that could be evaluated as potential immunotherapeutic molecules in near future. Herein, we characterized the transcriptome of the adult stage of the human whipworm T. trichiura, using next-generation sequencing technology and a de novo assembly strategy. Nearly 17.6 million high-quality clean reads were assembled into 6414 contiguous sequences, with an N50 of 1606bp. In total, 5673 protein-encoding sequences were confidentially identified in the T. trichiura adult worm transcriptome; of these, 1013 sequences represent potential newly discovered proteins for the species, most of which presenting orthologs already annotated in the related species T. suis. A number of transcripts representing probable novel non-coding transcripts for the species T. trichiura were also identified. Among the most abundant transcripts, we found sequences that code for proteins involved in lipid transport, such as vitellogenins, and several chitin-binding proteins. Through a cross-species expression analysis of gene orthologs shared by T. trichiura and the closely related parasites T. suis and T. muris it was possible to find twenty-six protein-encoding genes that are consistently highly expressed in the adult stages of the three helminth species. Additionally, twenty transcripts could be identified that code for proteins previously detected by mass spectrometry analysis of protein fractions of the whipworm somatic extract that present immunomodulatory activities. Five of these transcripts were amongst the most highly expressed protein-encoding sequences in the T. trichiura adult worm. Besides, orthologs of proteins demonstrated to have potent immunomodulatory properties in related parasitic helminths were also predicted from the T. trichiura de novo assembled transcriptome.


Subject(s)
Antigens, Helminth/genetics , Transcriptome/genetics , Trichuriasis/parasitology , Trichuris/genetics , Adolescent , Amino Acid Sequence , Animals , Child , Child, Preschool , Ecuador , Female , Humans , Infant , Infant, Newborn , Male
6.
Cornea ; 30(2): 167-70, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20802312

ABSTRACT

PURPOSE: To evaluate the histopathological features of corneal graft failures over time. METHODS: A single-center retrospective analysis was performed on corneal specimens diagnosed as corneal graft failure retrieved from The Henry C. Witelson Ophthalmic Pathology Laboratory and Registry (Montreal, Canada) over a 9-year period. The corneal buttons were divided into 3 different groups according to the time between the diagnosis of corneal graft failure and regraft. Corneal specimens obtained during keratoplasty were subjected to hematoxylin and eosin and periodic acid-Schiff. Five different histopathological findings were evaluated in each specimen. RESULTS: Overall, the most common histopathological finding was endothelial decompensation (97.2%). Subepithelial pannus (38.9%), vessels in the corneal stroma (11.1%), and anterior synechiae (2.8%) were the other present findings. The inflammatory reaction was considered discrete in 83.3% of the cases. The only significant histopathological finding correlated with time was the presence of vessels in the corneal stroma (P = 0.0092). CONCLUSIONS: Corneal neovascularization, represented by the presence of vessels in the corneal stroma, was the only histopathological finding correlated with time. Because it is a known factor of poor prognosis, our findings strongly support that early regraft has higher chances of success.


Subject(s)
Corneal Stroma/pathology , Corneal Transplantation , Graft Rejection/pathology , Aged , Aged, 80 and over , Corneal Stroma/blood supply , Female , Humans , Male , Middle Aged , Neovascularization, Pathologic/pathology , Reoperation , Retrospective Studies , Time Factors
7.
Pathology ; 40(6): 623-6, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18752131

ABSTRACT

AIMS: Keratoconus is a bilateral and asymmetrical corneal ectasia. The pathophysiology of this disorder has yet to be fully elucidated. The purpose of our study was to document the prevalence of the most common morphological features of keratoconic corneas. METHODS: A retrospective analysis of 49 cases diagnosed as keratoconus between 2001 and 2006 was undertaken. Histopathological reports were reviewed to obtain data such as age and gender. Specimens were fixed in 10% buffered paraformaldehyde solution for 24 h, bisected through the centre of the button, and embedded in paraffin. Sections were stained with haematoxylin and eosin (H&E) and periodic acid-Schiff (PAS) for light microscopic examination. RESULTS: The studied group was composed of 29 men and 20 women. Age at the time of the penetrating keratoplasty was 39 +/- 14 years (mean +/- standard deviation). Forty of the 49 specimens (82%) presented with epithelial thinning. Other common features of keratoconus included breaks in Bowman's layer in 35 (71%), compaction of the stromal collagen fibres in 31 (63%), and folds in Descemet's membrane in 31 (63%) cases. Other less common histopathological findings were: presence of superficial iron deposits in 14 (29%), deep stromal scarring in 12 (24%), epithelial scarring in 11 (22%), endothelial cell loss in 11 (22%), and breaks in Descemet's membrane in nine (18%) cases. CONCLUSIONS: Some of the histopathological findings associated with keratoconus are subtle. It is important to be aware of them in order to properly confirm the clinical diagnosis.


Subject(s)
Cornea/pathology , Keratoconus/pathology , Female , Humans , Male , Middle Aged , Retrospective Studies
8.
Cornea ; 26(9): 1027-31, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17893527

ABSTRACT

PURPOSE: To determine the frequency and describe the histopathologic features of stromal corneal dystrophies over a 10-year period. METHODS: A single-centered, retrospective analysis was performed on corneal specimens diagnosed as stromal dystrophies retrieved from the Henry C. Witelson Ophthalmic Pathology Laboratory and Registry (Montreal, Canada) over a period of 10 years. Corneal specimens obtained during keratoplasty were subjected to hematoxylin and eosin, periodic acid-Schiff, and other special staining. RESULTS: During the period of the study, 885 corneal specimens from penetrating keratoplasties were received. Twenty-six (2.9%) specimens from a total of 22 patients showed stromal corneal dystrophies: 17 (65.4%) eyes with lattice dystrophy, 5 (19.2%) eyes with combined granular/lattice ("Avellino") dystrophy, 3 (11.5%) eyes with granular dystrophy, and 1 (3.9%) eye with macular dystrophy. CONCLUSIONS: Corneal stromal dystrophies have distinct histopathologic features, which can be diagnosed with routine and special staining, particularly for combined granular/lattice (Avellino) dystrophy. Clinically, combined granular/lattice (Avellino) dystrophy can have features of both lattice and granular dystrophies, which can be misleading for diagnosis. Lattice dystrophy was the most frequent stromal dystrophy in this particular population.


Subject(s)
Corneal Dystrophies, Hereditary/pathology , Corneal Stroma/pathology , Adult , Corneal Dystrophies, Hereditary/surgery , Female , Humans , Keratoplasty, Penetrating , Male , Middle Aged , Retrospective Studies
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