RESUMO
This study aimed to identify coagulase-positive staphylococci (CPS) species from 21 samples of clandestine Minas Frescal cheese, investigate the potential for deterioration in psychrotrophic and mesophilic conditions, verify the toxigenic potential of Staphylococcus aureus, and determine the antimicrobial susceptibility profile of toxigenic S. aureus. Species determination was performed based on the detection of ß-hemolysis in 5% ovine blood agar; fermentation of mannitol, maltose, and trehalose sugars; and production of acetoin. After species determination, DNA extraction and analysis was performed for S. aureus colonies for genes encoding staphylococcal toxins (eta, etb, tst, sea, seb, sec, sed, and see) using 2 multiplex PCR assays. Isolates identified as toxigenic S. aureus were tested for antimicrobial susceptibility to tetracycline, erythromycin, clindamycin, gentamicin, ciprofloxacin, sulfazotrim, trimethoprim, streptomycin, cefoxitin, vancomycin and enrofloxacin. Elevated CPS counts were observed with an average of >6 log cfu/g. Of the 355 isolates, 177 (49.86%) were identified as S. aureus. Staphylococcus hyicus, Staphylococcus intermedius, Staphylococcus delphini, and Staphylococcus coagulans were identified in 3 (0.84%), 2 (0.56%), 2 (0.56%), and 1 (0.28%) isolates, respectively. Of the total number of S. aureus, 25 (52.08%) were positive for the gene that encodes for toxic shock toxin (TSST-1). Another 16 (33.33%) were positive for the sea gene, and 4 isolates (8.33%) were positive for see and one isolate each was positive for seb (2.08%), sec (2.08%), and etb (2.08%) genes. All isolates demonstrated lipolytic activity under mesophilic and psychrotrophic conditions. S. intermedius and S. hyicus had the most prominent proteolytic potential. Multidrug resistance was observed in most of the potentially toxigenic isolates, with clindamycin having the lowest efficiency (40%), whereas the aminoglycosides (gentamicin and streptomycin) had the highest effectiveness demonstrating inhibition in all evaluated isolates. Methicillin-resistant S. aureus (MRSA) was detected. Minas Frescal cheeses, marketed in the north of Tocantins in the Brazilian Amazon region, do not comply with legal quality standards and pose a public health risk due to the enterotoxigenic potential of multiresistant isolates, in addition to low shelf life of the samples given the high spoilage potential of this microbiota.
Assuntos
Queijo , Staphylococcus aureus Resistente à Meticilina , Animais , Ovinos , Staphylococcus aureus , Coagulase/genética , Staphylococcus aureus Resistente à Meticilina/genética , Clindamicina , Staphylococcus , Antibacterianos/farmacologia , Estreptomicina , GentamicinasRESUMO
AIM: To analyse the antimicrobial and biological properties of a new bioceramic intracanal medicament (Bio-C Temp), and to compare it with two calcium hydroxide-based intracanal medicaments (Calen® and UltraCal® XS). METHODOLOGY: The direct contact and the crystal violet tests were performed to assess the antimicrobial activity of intracanal medicaments against Enterococcus faecalis. The cytocompatibility and the effect of the medication on the biology of the human osteoblast-like cell line (Saos-2) were evaluated with methylthiazole tetrazolium (MTT), neutral red, alkaline phosphatase activity and mineralization (alizarin red) assays. The data were analysed using one-way anova and Tukey's tests, two-way anova and Bonferroni's tests, or Kruskal-Wallis and Dunn's tests (α = 0.05). RESULTS: Bio-C Temp had significantly less antibacterial activity and biofilm biomass reduction than the other intracanal medicaments (P < 0.05). There was no difference in the viability of Saos-2 exposed to the various intracanal medicaments, except regarding the 1 : 2 dilution, when the Bio-C Temp group had significantly lower cell viability than the UltraCal® XS and Calen® groups (P < 0.05). Bio-C Temp induced significantly greater ALP activity than the other intracanal medicaments (P < 0.05) at day 1. Calen® induced significantly greater deposition of mineralized nodules than the other intracanal medicaments (P < 0.05), and no difference was observed between Bio-C Temp and UltraCal® XS (P > 0.05). CONCLUSIONS: Bio-C Temp had similar cytocompatibility at higher dilutions, and higher or similar induction of ALP activity and deposition of mineralized nodules in comparison with Calen® and UltraCal® XS. However, it had significantly less antibacterial and antibiofilm activity than Calen® and UltraCal® XS.
Assuntos
Anti-Infecciosos , Hidróxido de Cálcio , Antibacterianos/farmacologia , Biologia , Hidróxido de Cálcio/farmacologia , Humanos , OsteoblastosRESUMO
AIM: To investigate the biocompatibility, type of cell death, osteogenic bioactivity and mRNA expression of the osteogenic markers, induced by CaneCPI-1 in human dental pulp cells (hDPCs). METHODOLOGY: hDPCs exposed to CaneCPI-1 and not exposed (control) were evaluated for cell viability by the 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay; apoptosis by flow cytometry; alkaline phosphatase (ALP) activity by calculation of thymolphthalein release; gene expression of bone morphogenetic protein 2 (BMP-2), runt-related transcription factor 2 (RUNX2), ALP, osteocalcin (OC), bone sialoprotein (BSP) by qPCR; and mineralized nodules production by using alizarin red staining. The data were analysed by one-way analysis of variance (anova) and Turkey's post-test, two-way anova and Bonferroni post-test or t-test (P < 0.05). RESULTS: CaneCPI-1 induced no apoptosis and had no cytotoxic effect, except in the concentration of 33.20 µm, in which cell viability was significantly lower than the control (α-MEM nonosteogenic medium serum-free) (P < 0.05). There was significantly greater ALP activity, greater expression of the BMP-2, RUNX2, ALP, OC and BSP genes and greater mineralized nodules production in the CaneCPI-1 group in comparison with the control or osteogenic α-MEM control (α-MEM osteogenic medium - L-ascorbic acid and ß-glycerophosphate) (P < 0.05). CONCLUSIONS: CaneCPI-1 was cytocompatible and also induced the differentiation of hDPCs in osteogenic phenotype in vitro. CaneCPI-1 is a promising molecule to induce pulp repair.
Assuntos
Cisteína Proteases , Saccharum , Fosfatase Alcalina , Diferenciação Celular , Células Cultivadas , Inibidores de Cisteína Proteinase , Polpa Dentária , Humanos , Osteogênese , Cistatinas SalivaresRESUMO
AIM: To assess the effects of octenidine dihydrochloride (OCT) on eukaryotic cells and the cytotoxicity of OCT associated with sodium hypochlorite - NaOCl (NaOCl/OCT). METHODOLOGY: L929 fibroblasts and human osteoblast-like cells (Saos-2) were exposed to 0.1% OCT, 2% CHX, 2.5% NaOCl, 5.25% NaOCl and mixtures of 5.25% NaOCl and 0.1% OCT (NaOCl/OCT) at 90 : 10, 80 : 20 and 50 : 50 ratios. Cell viability was assessed by methyl-thiazol-tetrazolium (MTT) and neutral red (NR) assays; type of cell death, by flow cytometry; cytoskeleton, by actin and α-tubulin fluorescence; and alkaline phosphatase (ALP) activity, by thymolphthalein release. The data were analysed by two-way ANOVA and Bonferroni tests (α = 0.05). RESULTS: MTT and NR assays revealed that 0.1% OCT had the lowest cytotoxicity (P < 0.05), followed by 2% CHX (P < 0.05). The 2.5% NaOCl, NaOCl/OCT 80 : 20 and NaOCl/OCT 50 : 50 solutions had intermediate cytotoxicity. NaOCl 5.25% and NaOCl/OCT 90 : 10 had the highest cytotoxicity (P < 0.05). The OCT group had a higher percentage of viable cells than the NaOCl and CHX groups (P < 0.05), and induced apoptosis at higher doses. The cytoskeleton alterations were observed at 0.12%, 0.6% and 2.02% for the NaOCl, CHX and OCT groups, respectively. The solutions did not induce ALP activity. CONCLUSION: Octenidine dihydrochloride was less cytotoxic, induced apoptosis at higher doses, caused few changes in the cytoskeleton and did not induce alkaline phosphatase activity. In addition, octenidine dihydrochloride reduced the cytotoxicity of 5.25% NaOCl when combined at 20 and 50%.
Assuntos
Irrigantes do Canal Radicular , Hipoclorito de Sódio , Clorexidina , Células Eucarióticas , Humanos , Iminas , PiridinasRESUMO
AIM: To evaluate the cytocompatibility, bioactive potential, antimicrobial and antibiofilm activities of an experimental calcium silicate-based endodontic sealer, in comparison with TotalFill BC Sealer and AH Plus. METHODOLOGY: Cytocompatibility was assessed by methyltetrazolium (MTT) and neutral red (NR) assays, after exposure of the Saos-2 cells to the sealer extracts (1 : 2, 1 : 4, 1 : 8, 1 : 16 and 1 : 32 dilutions) for 24 h. The sealers were manipulated and placed in 12-well culture plates and exposed to ultraviolet light; then, 5 mL of DMEM without serum was added. Cell bioactivity was evaluated by alkaline phosphatase activity (ALP) and Alizarin red staining (ARS). Antimicrobial and antibiofilm activities were evaluated by direct contact test (DCT) on planktonic cells (DCTPC) and modified DCT on biofilm formed in bovine dentine blocks (MDCT). MTT, NR and ALP data were analysed by two-way anova and Bonferroni tests; ARS data by anova and Tukey's tests; and the microbiological data by Kruskal-Wallis and Dunn tests (α = 0.05). RESULTS: The experimental sealer, TotalFill BC and AH Plus were not cytotoxic to Saos-2, in comparison with the negative control (P > 0.05). Greater ALP was observed after 7 days of exposure of Saos-2 to AH Plus and the experimental sealer (P < 0.05) when compared to the control. Significantly greater mineralized nodule production was observed for TotalFill BC and the experimental sealer (P < 0.05). In DCTPC, the experimental sealer and TotalFill BC were associated with a significantly greater reduction of E. faecalis (P < 0.05) and eliminated C. albicans. In MDCT, the experimental sealer and TotalFill BC had significantly greater antibiofilm efficacy (P < 0.05). CONCLUSIONS: The experimental calcium silicate-based sealer was cytocompatible, bioactive, antimicrobial against E. faecalis and C. albicans and effective against E. faecalis biofilms, with potential for use in root canal treatment.
Assuntos
Anti-Infecciosos , Materiais Restauradores do Canal Radicular , Animais , Cálcio , Compostos de Cálcio , Bovinos , Resinas Epóxi , Teste de Materiais , SilicatosRESUMO
AIM: To investigate the biocompatibility, osteogenic bioactivity and mRNA expression of the osteo/odontogenic markers bone morphogenetic protein 2 (BMP-2), osteocalcin (OC) and alkaline phosphatase (ALP), induced by heparin in human dental pulp cells (hDPCs). METHODOLOGY: hDPCs were exposed to the heparin, and cell viability was assessed by 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT), and cell death was evaluated by flow cytometry. Osteogenic bioactivity was evaluated by the alkaline phosphatase (ALP) assay, and the detection of calcium deposits by alizarin red staining (ARS). The gene expression of BMP-2, OC and ALP was quantified with real-time PCR. Statistical analysis was performed with ANOVA and Bonferroni or Tukey post-test and t-test (α = 0.05). RESULTS: Heparin had no cytotoxic effect and did not induce apoptosis. After 3 days, heparin had significantly higher ALP activity in comparison with the control (P < 0.05). Heparin had a significant (P < 0.05) stimulatory effect on the formation of mineralized nodules. BMP-2 and OC mRNA expressions were significantly higher in cells exposed to heparin than control group after 1 day (P < 0.05). CONCLUSIONS: Heparin was biocompatible in hDPCs, induced osteogenic bioactivity and enhanced mRNA expression of osteo/odontogenic markers BMP-2 and OC. These results suggest that heparin has potential to induce osteo/odontogenic cell differentiation of hDPCs.
Assuntos
Polpa Dentária , Heparina , Fosfatase Alcalina , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , OdontogêneseRESUMO
AIM: To evaluate the cytotoxicity and the mechanism of cell aggression of peracetic acid (PA) in comparison with sodium hypochlorite (NaOCl). METHODOLOGY: L929 fibroblasts were exposed to 1% PA and 2.5% NaOCl, at several dilutions for 10 min. The following parameters were evaluated: cell metabolism by methylthiazol tetrazolium assay, external morphology by scanning electron microscopy, ultrastructure by transmission electron microscopy, the cytoskeleton by means of actin and α-tubulin labelling, and the type of cell death by flow cytometry (apoptosis/necrosis). The data were analysed by two-way anova and the Bonferroni post-test (α = 0.05). RESULTS: The PA group had lower cell viability and a higher percentage of necrotic cells than the NaOCl group (P < 0.05). Both solutions diminished cell metabolism, led to destructuring of the cytoskeleton, created changes in the external morphology, resulted in the accumulation of proteins in the rough endoplasmic reticulum and induced cell death predominantly by necrosis. However, these changes were observed in lower doses of PA when compared with NaOCl. CONCLUSIONS: Although they had the same mechanism of cytotoxicity, 1% PA had greater cytotoxic potential than 2.5% NaOCl.
Assuntos
Apoptose/efeitos dos fármacos , Desinfetantes/toxicidade , Fibroblastos/efeitos dos fármacos , Ácido Peracético/toxicidade , Animais , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/ultraestrutura , Citometria de Fluxo , Camundongos , Microscopia Eletrônica , Necrose , Hipoclorito de Sódio/toxicidadeRESUMO
AIM: To evaluate the biocompatibility and mineralized nodule formation of an experimental tricalcium silicate cement with tantalum oxide (TSC/Ta2 O5 ) as radiopacifier, Neo MTA Plus (Avalon Biomed Inc., Bradenton, FL, USA) and MTA (Angelus, Londrina, PR, Brazil) on human osteoblast-like cells (Saos-2). METHODOLOGY: Biocompatibility was evaluated by 3-(4,5-dimethyl-thiazoyl)-2,5-diphenyl-tetrazolium bromide (MTT) and neutral red (NR) assays, after exposure of Saos-2 to cement extracts at 1 : 1, 1 : 2, 1 : 4 and 1 : 8 dilutions for 24 h. Bioactivity was evaluated by alkaline phosphatase (ALP) activity, and calcium deposits were detected with alizarin red staining (ARS). Statistical analysis was performed with analysis of variance and Bonferroni or Tukey post-test (α = 0.05). RESULTS: The MTT assay revealed lower cytotoxicity for NEO and MTA (P < 0.05), and higher for TSC/Ta2 O5 at 1 : 1 and 1 : 2 dilutions when compared to serum-free medium - control (P > 0.05). At 1 : 4 dilution, the TSC/Ta2 O5 cytotoxicity was similar to the control (P > 0.05). At 1 : 8 dilution, cell viability was significantly greater than the control (P < 0.05). Saos-2 cell viability performed using the NR assay at all dilutions revealed no cytotoxic effect of MTA, NEO and TSC/Ta2 O5 . ALP activity at 1 and 3 days was similar to the control (P > 0.05). TSC/Ta2 O5 had significantly greater ALP activity at 7 days when compared with the control (P < 0.05). All materials induced the production of mineralized nodules, and NEO produced significantly more mineralized nodules than MTA and TSC/Ta2 O5 (P < 0.05). CONCLUSIONS: Neo MTA Plus and TSC/Ta2 O5 were biocompatible and induced ALP activity in Saos-2 cells. Both materials induced mineralized nodule formation by Saos-2 with Neo MTA Plus producing significantly more.
Assuntos
Materiais Biocompatíveis/farmacologia , Compostos de Cálcio/farmacologia , Cimentos Dentários/farmacologia , Osteoblastos/efeitos dos fármacos , Óxidos/farmacologia , Agentes de Capeamento da Polpa Dentária e Pulpectomia/farmacologia , Silicatos/farmacologia , Tantálio/farmacologia , Fosfatase Alcalina/metabolismo , Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Combinação de Medicamentos , Humanos , Técnicas In Vitro , Teste de Materiais , Sais de TetrazólioRESUMO
AIM: To evaluate the effect of MTA and Biodentine on viability, osteogenic differentiation and BMP-2 expression in osteogenic cells. METHODOLOGY: Saos-2 cells were used as a model of osteoblastic cells. Overexpression of BMP-2 was induced by transfection of a CMV-driven plasmid construct including the human BMP-2 coding sequence, and stably transfected cells were selected. Cell viability was assessed by the mitochondrial dehydrogenase enzymatic (MTT) assay. The bioactivity of the materials was evaluated by the alkaline phosphatase (ALP) assay and detection of calcium deposits with alizarin red staining (ARS). The gene expression of BMP-2 and ALP was quantified with real-time PCR. Statistical analysis was performed with analysis of variance and Bonferroni or Tukey post-test (α = 0.05). RESULTS: Viability tests revealed that MTA and Biodentine were not cytotoxic at the higher dilution (1 : 8) to BMP-2-transfected cells. MTA and Biodentine exhibited the highest ALP activity when compared to the Saos-BMP-2-unexposed control group (P < 0.05). Cell exposure to Biodentine and MTA had a significant stimulatory effect on the formation of mineralized nodules (P < 0.05). The highest increase in BMP-2 gene expression was observed after 3 days of BMP-2-transfected cells exposure to MTA and Biodentine in non-osteogenic medium in relation to Saos-BMP-2-unexposed control cells (P < 0.05). Exposure of cells to MTA in osteogenic medium for 1 day increased ALP gene expression by approximately 1.3-fold in relation to Saos-BMP-2-unexposed control cells (P < 0.05). CONCLUSIONS: Both MTA and Biodentine showed biocompatibility and bioactivity in Saos-BMP-2 overexpressing cells. Biodentine had a significantly greater effect on mineralization than MTA. Both MTA and Biodentine enhanced BMP-2 mRNA expression in the transfected system. Both MTA and Biodentine are suitable materials to improve osteoblastic cell mineralization.
Assuntos
Compostos de Alumínio/farmacologia , Proteína Morfogenética Óssea 2/metabolismo , Compostos de Cálcio/farmacologia , Osteoblastos/metabolismo , Óxidos/farmacologia , Silicatos/farmacologia , Fosfatase Alcalina/metabolismo , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Combinação de Medicamentos , Humanos , Teste de Materiais , Reação em Cadeia da Polimerase em Tempo Real , TransfecçãoRESUMO
AIM: To compare the bioactivity of Biodentine (BIO, Septodont), MTA Plus (MTA P, Avalon) and calcium silicate experimental cement (CSC) with resin (CSCR) associated with zirconium (CSCR ZrO2 ) or niobium (CSCR Nb2 O5 ) oxide as radiopacifiers. METHODOLOGY: According to the relevance of osteoblastic cell response for mineralized tissue repair, human osteoblastic cells (Saos-2) were exposed to test materials and assessed for viability (MTT), cell proliferation, gene expression of alkaline phosphatase (ALP) osteogenic marker by real-time PCR (RT-qPCR), ALP activity assay and alizarin red staining (ARS) to detect mineralization nodule deposition in osteogenic medium. Unexposed cells acted as the control group (C). Statistical analysis was carried out using ANOVA and the Bonferroni post-test (P < 0.05). RESULTS: All tested cements showed dose-dependent responses in cell viability (MTT). Exposed cells revealed good viability (80-130% compared to the control group) in the highest dilutions of all types of cement. MTA P, BIO and CSCR ZrO2 significantly increased the velocity of cell proliferation after three days of cell exposure in the wound-healing assay (P < 0.05), which corroborated MTT data. On day 3, the ALP transcript level increased, especially to CSCR Nb2 O5 (P < 0.05). All cements exhibited suitable ALP enzyme activity, highlighting the 7-day period of cell exposure. ARS, CSCR Nb2 O5 , revealed a significant potential to induce mineralization in vitro. CONCLUSIONS: All materials had suitable biocompatibility and bioactivity. The MTA P, BIO and CSCR ZrO2 groups had the highest viability rates and velocity of proliferation whilst the CSCR Nb2 O5 group produced more mineralized nodules.
Assuntos
Compostos de Alumínio/farmacologia , Materiais Biocompatíveis/farmacologia , Compostos de Cálcio/farmacologia , Cimentos Dentários/farmacologia , Osteoblastos/efeitos dos fármacos , Óxidos/farmacologia , Materiais Restauradores do Canal Radicular/farmacologia , Silicatos/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Combinação de Medicamentos , Humanos , Teste de Materiais , Nióbio/farmacologia , Zircônio/farmacologiaRESUMO
AIM: To investigate the cytotoxicity, osteogenic bioactivity and mRNA expression of osteogenic markers of bone morphogenetic protein 2 (BMP-2), osteocalcin (OC) and alkaline phosphatase (ALP) induced by the extracts of set MTA Plus (MTA P) (Avalon Biomed Inc. Bradenton, FL, USA) in comparison with MTA (Angelus, Londrina, PR, Brazil) on human dental pulp cells (hDPCs). METHODOLOGY: Cell viability was assessed by mitochondrial dehydrogenase enzymatic (MTT) assay, and the mechanism of cell death was evaluated by flow cytometry. Bioactivity was evaluated by alkaline phosphatase (ALP) assay and detection of calcium deposits with alizarin red staining (ARS). The gene expression of BMP-2, OC and ALP was quantified with real-time PCR. Statistical analysis was performed with analysis of variance and Bonferroni or Tukey post-test (α = 0.05). RESULTS: MTA and MTA P were not cytotoxic and did not induce apoptosis. MTA P had significant higher ALP activity in relation to MTA and the control (P < 0.05). MTA had a significantly higher percentage of mineralized area than MTA P (P < 0.05). The expression of BMP2 and OC mRNA was significantly higher in cells exposed to MTA than MTA P after 1 day (P < 0.05). At day 3, the mRNA expression of ALP was significantly higher in MTA P compared with MTA (P < 0.05). CONCLUSIONS: MTA and MTA Plus were noncytotoxic, increased mineralization processes in vitro and induced the expression of osteogenic markers.
Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Cimentos Dentários/farmacologia , Polpa Dentária/citologia , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Óxidos/farmacologia , Materiais Restauradores do Canal Radicular/farmacologia , Silicatos/farmacologia , Adolescente , Adulto , Fosfatase Alcalina/genética , Apoptose/efeitos dos fármacos , Proteína Morfogenética Óssea 2/genética , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Polpa Dentária/efeitos dos fármacos , Combinação de Medicamentos , Expressão Gênica/efeitos dos fármacos , Humanos , Osteocalcina/genética , RNA Mensageiro/genética , Adulto JovemRESUMO
Systemic lupus erythematosus (SLE) is an autoimmune disorder of the connective tissue with a wide and heterogeneous spectrum of manifestations, with renal and neurological involvement usually related to worse prognosis. SLE more frequently affects females of reproductive age, and a high prevalence and renal manifestation seem to be associated with non-European ethnicity. The present study aims to investigate candidate loci to SLE predisposition and evaluate the influence of ethnic ancestry in the disease risk and clinical phenotypic heterogeneity of lupus at onset. Samples represented by 111 patients and 345 controls, originated from the city of Belém, located in the Northern Region of Brazil, were investigated for polymorphisms in HLA-G, HLA-C, SLC11A1, MTHFR, CASP8 and 15 KIR genes, in addition to 89 Amerindian samples genotyped for SLC11A1. We also investigated 48 insertion/deletion ancestry markers to characterize individual African, European and Amerindian ancestry proportions in the samples. Predisposition to SLE was associated with GTGT deletion at the SLC11A1 3'UTR, presence of KIR2DS2 +/KIR2DS5 +/KIR3DS1 + profile, increased number of stimulatory KIR genes, and European and Amerindian ancestries. The ancestry analysis ruled out ethnic differences between controls and patients as the source of the observed associations. Moreover, the African ancestry was associated with renal manifestations.
Assuntos
Proteínas de Transporte de Cátions/genética , Etnicidade/genética , Marcadores Genéticos , Predisposição Genética para Doença , Lúpus Eritematoso Sistêmico/genética , Polimorfismo Genético , Receptores KIR/genética , Adulto , Idade de Início , Brasil , Cidades , Feminino , Frequência do Gene , Humanos , Lúpus Eritematoso Sistêmico/etnologia , Masculino , Receptores KIR3DS1/genéticaRESUMO
Selenophosphate synthetase (EC 2.7.9.3), the product of the selD gene, produces the biologically active selenium donor compound, monoselenophosphate, from ATP and selenide, for the synthesis of selenocysteine. The kinetoplastid Leishmania major and Trypanosoma brucei selD genes were cloned and the SELD protein overexpressed and purified to apparent homogeneity. The selD gene in L. major and T. brucei are respectively 1197 and 1179 bp long encoding proteins of 399 and 393 amino acids with molecular masses of 42.7 and 43 kDa. The molecular mass of 100 kDa for both (L. major and T. brucei) SELDs is consistent with dimeric proteins. The kinetoplastid selD complement Escherichia coli (WL400) selD deletion confirming it is a functional enzyme and the specific activity of these enzymes was determined. A conserved Cys residue was identified both by multiple sequence alignment as well as by functional complementation and activity assay of the mutant (Cys to Ala) forms of the SELD identifying this residue as essential for the catalytic function.
Assuntos
Leishmania major/enzimologia , Fosfotransferases/química , Proteínas de Protozoários/química , Selenocisteína/metabolismo , Trypanosoma brucei brucei/enzimologia , Sequência de Aminoácidos , Animais , Clonagem Molecular , Cisteína/metabolismo , Teste de Complementação Genética , Leishmania major/metabolismo , Dados de Sequência Molecular , Fosfotransferases/isolamento & purificação , Fosfotransferases/metabolismo , Proteínas de Protozoários/isolamento & purificação , Proteínas de Protozoários/metabolismo , Alinhamento de Sequência , Trypanosoma brucei brucei/metabolismoRESUMO
Selenoproteins result from the incorporation of selenocysteine (Sec-U) at an UGA-stop codon positioned within a gene's open reading frame and directed by selenocysteine insertion sequence (SECIS) elements. Although the selenocysteine incorporation pathway has been identified in a wide range of organisms it has not yet been reported in the Kinetoplastida Leishmania and Trypanosoma. Here we present evidence consistent with the presence of a selenocysteine biosynthetic pathway in Kinetoplastida. These include the existence of SECIS-containing coding sequences in Leishmania major and Leishmania infantum, the incorporation of (75)Se into Leishmania proteins, the occurrence of selenocysteine-tRNA (tRNA (sec) (uca)) in both Leishmania and Trypanosoma and in addition the finding of all genes necessary for selenocysteine synthesis such as SELB, SELD, PSTK and SECp43. As in other eukaryotes, the Kinetoplastids have no identifiable SELA homologue. To our knowledge this is the first report on the identification of selenocysteine insertion machinery in Kinetoplastida, more specifically in Leishmania, at the sequence level.
Assuntos
Leishmania/metabolismo , Proteínas de Protozoários/metabolismo , Selenoproteínas/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA de Protozoário/genética , Leishmania/genética , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA Mensageiro/genética , RNA de Protozoário/química , RNA de Protozoário/genética , RNA de Transferência Aminoácido-Específico/química , RNA de Transferência Aminoácido-Específico/genética , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido NucleicoRESUMO
OBJECTIVE: This study aimed to describe the prevalence of overweight and obesity (OW+O) among Brazilian adolescents and to identify risks for subpopulations defined according to the five country macro-regions and situation (urban-rural) of the domiciles, income, years of school attendance, age and sex. DESIGN: A nationwide home-based survey representative of the Brazilian civilian noninstitutionalized population, performed in 1989. METHODS: The sampling plans followed a stratified, multistage, probability cluster design in The National Research of Health and Nutrition sample, which collected anthropometric data of 14,455 domiciles. In all, 13,715 adolescents ranging from 10 to 19 y of age were studied. The OW+O was defined from a body mass index (BMI) equal or superior to the 85th percentile of the reference population of the NCHS. The prevalences in the different studied groups were compared using the adjusted odds ratio in logistic regression models. RESULTS: The prevalence of OW+O was of 7.7%, reaching 10.6% within the female group and 4.8% within the male group. A direct relation could be established between the socioeconomic level and OW+O. Adolescents of the most industrialized region of the country presented a risk of OW+O 1.86 (95% CI 1.51-2.30) times higher than that found in the least developed region. Male youngsters who lived in urban areas were more liable (OR=1.71, 95% CI 1.30-2.25) to overweight than their counterparts of rural areas. The occurrence of menarche increased two and a half times (OR=2.58, 95% CI 2.11-3.15) the risk of OW+O within the female group of adolescents. CONCLUSIONS: The results demonstrate a low prevalence of OW+O among Brazilian adolescents when compared with adolescents of more industrialized regions. The OW+O is twice as high within the female group, which represents a much greater difference than the one encountered in industrialized countries, probably owing to the muscular work carried out preponderantly by male adolescents of lower socioeconomic levels. Higher prevalences in subpopulations of higher socioeconomic level and of more industrialized regions show the great need for differentiated actions to control overweight and obesity in the country.
Assuntos
Obesidade/epidemiologia , Adolescente , Adulto , Índice de Massa Corporal , Brasil/epidemiologia , Criança , Análise por Conglomerados , Estudos Transversais , Demografia , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Obesidade/prevenção & controle , Prevalência , Fatores de Risco , Saúde da População Rural , Distribuição por Sexo , Fatores Socioeconômicos , Saúde da População UrbanaRESUMO
Xylanase recovery by reversed micelles using cationic surfactant (N-benzyl- N-dodecyl-N-bis(2-hydroxyethhyl)ammonium chloride) BDBAC was evaluated under different experimental conditions. A full factorial design with center point was employed to verify the influence of different factors on the recovery. A mathematical model was found to represent the xylanase yield (Y) as a function of BDBAC and hexanol: Y = 4.32 + 5.1B + 2.64D + 0.83B2 + 1.46D2, where B = BDBAC and D = hexanol. The highest xylanase recovery (27%), indicated by the model was attained at pH = 8.1, BDBAC = 0.38 M and hexanol = 8.6%. Under these conditions, and to test the model, a new xylanase extraction was performed in laboratory, giving 29.4% recovery yield, this value was similar to that predicted by the model.
RESUMO
INTRODUCTION: The correct identification of the underlying cause of death and its precise assignment to a code from the International Classification of Diseases are important issues to achieve accurate and universally comparable mortality statistics. These factors, among other ones, led to the development of computer software programs in order to automatically identify the underlying cause of death. OBJECTIVE: This work was conceived to compare the underlying causes of death processed respectively by the Automated Classification of Medical Entities (ACME) and the "Sistema de Seleção de Causa Básica de Morte" (SCB) programs. MATERIAL AND METHOD: The comparative evaluation of the underlying causes of death processed respectively by ACME and SCB systems was performed using the input data file for the ACME system that included deaths which occurred in the State of S. Paulo from June to December 1993, totalling 129,104 records of the corresponding death certificates. The differences between underlying causes selected by ACME and SCB systems verified in the month of June, when considered as SCB errors, were used to correct and improve SCB processing logic and its decision tables. RESULTS: The processing of the underlying causes of death by the ACME and SCB systems resulted in 3,278 differences, that were analysed and ascribed to lack of answer to dialogue boxes during processing, to deaths due to human immunodeficiency virus [HIV] disease for which there was no specific provision in any of the systems, to coding and/or keying errors and to actual problems. The detailed analysis of these latter disclosed that the majority of the underlying causes of death processed by the SCB system were correct and that different interpretations were given to the mortality coding rules by each system, that some particular problems could not be explained with the available documentation and that a smaller proportion of problems were identified as SCB errors. CONCLUSION: These results, disclosing a very low and insignificant number of actual problems, guarantees the use of the version of the SCB system for the Ninth Revision of the International Classification of Diseases and assures the continuity of the work which is being undertaken for the Tenth Revision version.
PIP: Problems in collecting data on causes of death are examined by comparing data collected in two different programs in Brazil, the Automated Classification of Medical Entities (ACME) and the Sistema de Selecao de Causa Basica de Morte (SCB). The data concern 129,104 death certificates recorded in the state of Sao Paulo in 1993. The analysis revealed 3,278 differences in the causes of death between the two systems, primarily due to failure to record the necessary information, deaths associated with HIV for which there was no provision for recording the appropriate information, and coding or keying errors. The relatively low and insignificant number of problems recorded indicates the high quality of the data collected, particularly in the SCB system.
Assuntos
Causas de Morte , Sistemas de Informação , Humanos , Estatísticas VitaisRESUMO
Following an epidemic of type I dengue in late 1990, the municipality of Ribeirão Preto (State of São Paulo, Brazil) assumed direct responsibility for the control of Aedes aegypti larvae. Control activities are presented in this report and are based on popular participation in environmental management. Massive use of the communications media, participation by schoolchildren, constant contact with the population, and integration of various public agencies are the program's priorities. Although the drop in the number of susceptibles may have played a role in the reduction of cases after the initial epidemic, the intense preventive campaign certainly helped quell the disease in the city, since changes were observed in the behavior of the population towards potential breeding sites. The occurrence of new cases in recent years appears to be related to greater circulation of the virus in both the State of São Paulo and Brazil as a whole, indicating the need for control measures at the national and continental level, without which it will be difficult to maintain low transmission rates, even in areas submitted to intense preventive work
Assuntos
Dengue/prevenção & controle , População Urbana , Aedes , Animais , Brasil/epidemiologia , Criança , Participação da Comunidade , Dengue/epidemiologia , Dengue/transmissão , Educação em Saúde/métodos , Humanos , Incidência , Controle de Insetos/métodos , Insetos Vetores , Meios de Comunicação de MassaRESUMO
OBJECTIVE: To evaluate the relationship between the nutritional status of the youngest child under 48 months of age (in families with the biological mother present) and their mothers among 3906 children selected from a sample of a national survey in 1989 (PNSN). RESULTS: Malnutrition was present in 5.8% of the children. From these, 21.8%, 60.9% and 17.3% had overweight/obese, eutrophic and malnourished mothers, respectively. Stratified analyses taking into account the regions, situation, income distribution and mother's educational level demonstrated that a lower proportion of malnourished children was concurrent with a higher proportion of overweight/obese mothers. The Kappa test evidenced a poor agreement between the nutritional conditions of the child-mother pairs (K < = 0.048). CONCLUSIONS: When the proportion of malnourished children decreased within the analyzed groups, the proportion of overweight/obese mothers increased. Such an epidemiological pattern indicates that within groups in which malnutrition is less prevalent, the proportion of children for whom a lack of food in the household is the main determinant factor for malnutrition is lower.