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1.
Reprod Domest Anim ; 59(3): e14553, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38501644

RESUMO

This study evaluated the efficacy of the administration of different doses of equine chorionic gonadotropin (eCG; 0 IU, 200 IU, or 300 IU) at the time of the progesterone device removal in 2-year-old Nelore (Bos indicus) heifers synchronized for fixed-timed artificial insemination (FTAI). On day 0 (D0), a total of 398 heifers received 2 mg of oestradiol benzoate i.m., 0.53 mg of cloprostenol i.m., and an eight-day previously used (second use) intravaginal device containing 1 g of progesterone (P4). Eight days later (D8), simultaneous with the P4 device removal, 0.5 mg of oestradiol cypionate i.m. and 0.53 mg of cloprostenol i.m. were administered. At the same time, heifers were randomly assigned to receive one of the following treatments: G-0 IU (n = 141; no eCG treatment), G-200 IU (n = 132; treated with 200 IU of eCG), and G-300 IU (n = 125; treated with 300 IU of eCG). FTAI was performed 48 h after the P4 device removal (D10). Ultrasonographic evaluations were performed at D0, D10, and D17. Heifers were scanned to measure the size of the largest follicle (LF), the presence, number, and size of the corpus luteum (CL), and the ovulation rate. Subsequently, at D40, the heifers underwent scanning to determine the pregnancy rate and identify any twin pregnancies. Additionally, at D70, scans were performed to assess pregnancy loss (PG). Data were analysed by orthogonal contrasts [C1 (eCG effect): control x (200 IU + 300 IU) and C2 (eCG dose effect): 200 IU × 300 IU]. On D0, CL presence was similar between the groups [G-0 IU = 65.2% (92/141), G-200 IU = 55.3% (73/132), and G-300 IU = 63.2% (79/125); p = .16]. No interactions between the presence of CL on D0 and eCG treatment were found for any of the variables (p > .05). The diameter of the LF at FTAI (D10) was not influenced by eCG treatment (p = .22) or eCG dose (p = .18). However, treatment with eCG increased the diameter of the CL at D17 (G-0 IU = 15.7 ± 0.3 mmb , G-200 IU = 16.6 ± 0.2 mma , and G-300 IU = 16.6 ± 0.3 mma ; p = .001), regardless of the dose used (p = .94). The ovulation rate was higher in heifers treated with eCG [G-0 IU = 79.4%b (112/141), G-200 IU = 90.2%a (119/132), and G-300 IU = 93.6%a (117/125); p = .002], but there was no effect of eCG dose (p = .36). Pregnancy per AI (P/AI) on D40 [G-0 IU = 32.6%b (46/141), G-200 IU = 42.4%a (56/132), and G-300 IU = 42.4%a (53/125); P = 0.05] and D70 [G-0 IU = 29.1%b (41/141), G-200 IU = 40.9%a (54/132), and G-300 IU = 40.8%a (51/125); p = .02] were higher on heifers that received eCG; however, no dose effect was observed for P/AI on D40 (p = .89) nor D70 (p = .98). Pregnancy loss between D40 and D70 tended to reduce (p = .07) in eCG-treated heifers without dose effect (p = .91). Heifers with CL at D0 presented a greater follicle diameter (LF) on D10 (With CL = 11.2 ± 0.2 mm and Without CL = 10.2 ± 0.2 mm; p = .05), CL diameter on D17 (With CL = 15.8 ± 0.03 mm and Without CL = 11.8 ± 0.6 mm; p = .01), and ovulation rate [With CL = 95.5% (233/244) and Without CL = 74.7% (115/154); p = .01]. However, no difference in pregnancy rate at D40 (p = .52) and D70 (p = .84) was found. In conclusion, eCG treatment increases ovulation and pregnancy rates of heifers submitted to a FTAI protocol. Furthermore, eCG treatment increases the diameter of the CL after FTAI and reduces pregnancy losses. No dose effect was observed, suggesting Nelore (Bos indicus) heifers respond to 200 IU of eCG treatment for FTAI.


Assuntos
Doenças dos Bovinos , Doenças dos Cavalos , Gravidez , Bovinos , Animais , Feminino , Cavalos , Progesterona/farmacologia , Aborto Animal , Ovulação , Estradiol/farmacologia , Cloprostenol/farmacologia , Inseminação Artificial/veterinária , Inseminação Artificial/métodos , Sincronização do Estro/métodos
2.
Parasitol Res ; 120(1): 337-339, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33191447

RESUMO

Chigger mites are ectoparasites of terrestrial tetrapods and can cause dermatitis in the host, known as trombiculiasis. In Brazil, there are 73 species of chiggers; however, cats never have recorded as a host in this country. Here, we report the first record of chiggers parasitizing a domestic cat in Brazil; and a new locality for Eutrombicula tinami (Oudemans 1910) in the Rio Grande do Sul state, Brazil.


Assuntos
Doenças do Gato/parasitologia , Dermatite/veterinária , Larva/classificação , Trombiculíase/veterinária , Trombiculidae/classificação , Animais , Brasil , Gatos , Infestações por Ácaros/veterinária , Trombiculidae/genética
3.
Syst Parasitol ; 98(3): 277-283, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33786729

RESUMO

Trinidad and Tobago, a neotropical country, has 38 reported chigger species. Of these species, 18 were parasitizing bats. Here, we describe a new genus and species parasitizing a ghost-faced bat in this country.


Assuntos
Cavernas , Quirópteros , Trombiculíase , Trombiculidae , Animais , Quirópteros/parasitologia , Especificidade da Espécie , Trinidad e Tobago , Trombiculíase/parasitologia , Trombiculidae/classificação
4.
BMC Health Serv Res ; 20(1): 341, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32316963

RESUMO

BACKGROUND: The End TB Strategy calls for global scale-up of preventive treatment for latent tuberculosis infection (LTBI), but little information is available about the associated human resource requirements. Our study aimed to quantify the healthcare worker (HCW) time needed to perform the tasks associated with each step along the LTBI cascade of care for household contacts of TB patients. METHODS: We conducted a time and motion (TAM) study between January 2018 and March 2019, in which consenting HCWs were observed throughout a typical workday. The precise time spent was recorded in pre-specified categories of work activities for each step along the cascade. A linear mixed model was fit to estimate the time at each step. RESULTS: A total of 173 HCWs in Benin, Canada, Ghana, Indonesia, and Vietnam participated. The greatest amount of time was spent for the medical evaluation (median: 11 min; IQR: 6-16), while the least time was spent on reading a tuberculin skin test (TST) (median: 4 min; IQR: 2-9). The greatest variability was seen in the time spent for each medical evaluation, while TST placement and reading showed the least variability. The total time required to complete all steps along the LTBI cascade, from identification of household contacts (HHC) through to treatment initiation ranged from 1.8 h per index TB patient in Vietnam to 5.2 h in Ghana. CONCLUSIONS: Our findings suggest that the time requirements are very modest to perform each step in the latent TB cascade of care, but to achieve full identification and management of all household contacts will require additional human resources in many settings.


Assuntos
Administração de Caso , Pessoal de Saúde , Recursos em Saúde , Tuberculose Latente , Adulto , Benin , Canadá , Feminino , Gana , Humanos , Indonésia , Tuberculose Latente/diagnóstico , Tuberculose Latente/terapia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estudos de Tempo e Movimento , Vietnã
5.
Parasitology ; 146(8): 1006-1012, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30859917

RESUMO

Chagas disease (CD) is a neglected parasitic condition endemic in the Americas caused by Trypanosoma cruzi. Patients present an acute phase that may or not be symptomatic, followed by lifelong chronic stage, mostly indeterminate, or with cardiac and/or digestive progressive lesions. Benznidazole (BZ) and nifurtimox are the only drugs approved for treatment but not effective in the late chronic phase and many strains of the parasite are naturally resistant. New alternative therapy is required to address this serious public health issue. Repositioning and combination represent faster, and cheaper trial strategies encouraged for neglected diseases. The effect of imatinib (IMB), a tyrosine kinase inhibitor designed for use in neoplasias, was assessed in vitro on T. cruzi and mammalian host cells. In comparison with BZ, IMB was moderately active against different strains and forms of the parasite. The combination IMB + BZ in fixed-ratio proportions was additive. Novel 14 derivatives of IMB were screened and a 3,2-difluoro-2-phenylacetamide (3e) was as potent as BZ on T. cruzi but had low selectivity index. The results demonstrate the importance of phenotypic assays, encourage the improvement of IMB derivatives to reach selectivity and testify to the use of repurposing and combination in drug screening for CD.


Assuntos
Doença de Chagas/tratamento farmacológico , Reposicionamento de Medicamentos , Mesilato de Imatinib/farmacologia , Nitroimidazóis/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Linhagem Celular , Quimioterapia Combinada , Fibroblastos , Camundongos
6.
Arch Toxicol ; 92(7): 2275-2295, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29869127

RESUMO

3,4-Methylenedioxymethamphetamine (MDMA or "ecstasy") is a widespread drug of abuse with known neurotoxic properties. The present study aimed to evaluate the differential toxic effects of MDMA in adolescent and aged Wistar rats, using doses pharmacologically comparable to humans. Adolescent (post-natal day 40) (3 × 5 mg/kg, 2 h apart) and aged (mean 20 months old) (2 × 5 mg/kg, 2 h apart) rats received MDMA intraperitoneally. Animals were killed 7 days later, and the frontal cortex, hippocampus, striatum and cerebellum brain areas were dissected, and heart, liver and kidneys were collected. MDMA caused hyperthermia in both treated groups, but aged rats had a more dramatic temperature elevation. MDMA promoted serotonergic neurotoxicity only in the hippocampus of aged, but not in the adolescents' brain, and did not change the levels of dopamine or serotonin metabolite in the striatum of both groups. Differential responses according to age were also seen regarding brain p-Tau levels, a hallmark of a degenerative brain, since only aged animals had significant increases. MDMA evoked brain oxidative stress in the hippocampus and striatum of aged, and in the hippocampus, frontal cortex, and striatum brain areas of adolescents according to protein carbonylation, but only decreased GSH levels in the hippocampus of aged animals. The brain maturational stage seems crucial for MDMA-evoked serotonergic neurotoxicity. Aged animals were more susceptible to MDMA-induced tissue damage in the heart and kidneys, and both ages had an increase in liver fibrotic tissue content. In conclusion, age is a determinant factor for the toxic events promoted by "ecstasy". This work demonstrated special susceptibility of aged hippocampus to MDMA neurotoxicity, as well as impressive damage to the heart and kidney tissue following "ecstasy".


Assuntos
Envelhecimento/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Febre/induzido quimicamente , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Síndromes Neurotóxicas/etiologia , Envelhecimento/metabolismo , Animais , Encéfalo/metabolismo , Dopamina , Febre/metabolismo , Coração/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Síndromes Neurotóxicas/metabolismo , Ratos Wistar , Serotonina
7.
Protein Expr Purif ; 131: 60-69, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27856402

RESUMO

Visceral Leishmaniasis (VL) represents an important global health problem in several warm countries around the world. The main targets in this study are the two nucleoside triphosphate diphosphohydrolases (NTPDases) from Leishmania infantum chagasi that are the main etiologic agent of VL in the New World. These enzymes, called LicNTPDase1 and -2, are homologous to members 5 and 6 of the mammalian E-NTPDase/CD39 superfamily of enzymes. These enzymes hydrolyze nucleotides and accordingly can participate in the purine salvage pathways and in the modulation of purinergic signaling through the extracellular nucleotide-dependent host immune responses. They can therefore affect adhesion and infection of host cells and the parasite virulence. To further characterize these enzymes, in this work, we expressed LicNTPDase1 and -2 in the classical bacterial system Escherichia coli and mammalian cell system COS-7 cells. Our data demonstrate that changes in refolding after expression in bacteria can increase the activity of recombinant (r) rLicNTPDase2 up to 20 times but has no significant effect on rLicNTPDase1. Meanwhile, the expression in COS-7 led to a significant increase in activity for rLicNTPDase1.


Assuntos
Adenosina Trifosfatases , Antígenos CD , Apirase , Expressão Gênica , Leishmania infantum/genética , Redobramento de Proteína , Proteínas de Protozoários , Adenosina Trifosfatases/biossíntese , Adenosina Trifosfatases/química , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/isolamento & purificação , Animais , Antígenos CD/biossíntese , Antígenos CD/química , Antígenos CD/genética , Antígenos CD/isolamento & purificação , Apirase/biossíntese , Apirase/química , Apirase/genética , Apirase/isolamento & purificação , Células COS , Chlorocebus aethiops , Escherichia coli , Leishmania infantum/enzimologia , Proteínas de Protozoários/biossíntese , Proteínas de Protozoários/química , Proteínas de Protozoários/genética , Proteínas de Protozoários/isolamento & purificação , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
8.
J Periodontal Res ; 52(2): 292-299, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27363729

RESUMO

BACKGROUND AND OBJECTIVE: No previous study has directly compared the levels of matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) between smokers and individuals with diabetes mellitus (DM) with periodontitis. Therefore, the aim of this study was to evaluate the gene expression of MMP-1, MMP-2, MMP-8, MMP-9, TIMP-1 and TIMP-2 in tissues with chronic periodontitis (ChP) of smokers and individuals with type 2 DM. MATERIAL AND METHODS: Gingival biopsies were harvested from: non-smokers and non-diabetic individuals with ChP (n = 18) (ChP group); non-diabetic smokers (≥ 10 cigarettes per day for at least the past 5 years) with ChP (n = 18) (SChP group); non-smoking individuals with type 2 diabetes (glycated hemoglobin levels ≥ 7.5%) and ChP (n = 18) (DMChP group). The tissue levels of mRNA of MMP-1, MMP-2, MMP-8, MMP-9, TIMP-1 and TIMP-2 were evaluated by quantitative real-time polymerase chain reaction. RESULTS: The MMP-8 expression was the lowest in the ChP group (p < 0.05). The DMChP group presented increased mRNA levels of MMP-2 and MMP-9, when compared to the SChP group (p < 0.05). MMP-1 expression and the MMP-1/TIMP-1, MMP-2/TIMP-1, MMP-8/TIMP-1, MMP-9/TIMP-1, MMP-1/TIMP-2 and MMP-2/TIMP-2 ratios were higher in the DMChP group than in the ChP and SChP groups (p < 0.05). The DMChP group presented lower mRNA levels of TIMP-1 than the ChP group (p < 0.05). The MMP-8/TIMP-2 ratio was the highest in the SChP group (p < 0.05). CONCLUSION: Uncontrolled type 2 DM upregulates the ratio of MMP/TIMPs in sites with ChP more than smoking, which may contribute to a greater extracellular matrix degradation and periodontal breakdown in DM-related periodontitis.


Assuntos
Periodontite Crônica/complicações , Diabetes Mellitus Tipo 2/complicações , Metaloproteinases da Matriz/metabolismo , Fumar/efeitos adversos , Adulto , Periodontite Crônica/enzimologia , Periodontite Crônica/metabolismo , Diabetes Mellitus Tipo 2/enzimologia , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Gengiva/enzimologia , Gengiva/metabolismo , Humanos , Masculino , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 8 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo
9.
Arch Toxicol ; 91(4): 1871-1890, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27629428

RESUMO

Mitoxantrone (MTX) is an antineoplastic agent used to treat several types of cancers and on multiple sclerosis, which shows a high incidence of cardiotoxicity. Still, the underlying mechanisms of MTX cardiotoxicity are poorly understood and the potential toxicity of its metabolites scarcely investigated. Therefore, this work aimed to synthesize the MTX-naphthoquinoxaline metabolite (NAPHT) and to compare its cytotoxicity to the parent compound in 7-day differentiated H9c2 cells using pharmacological relevant concentrations (0.01-5 µM). MTX was more toxic in equivalent concentrations in all cytotoxicity tests performed [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide reduction, neutral red uptake, and lactate dehydrogenase release assays] and times tested (24 and 48 h). Both MTX and NAPHT significantly decreased mitochondrial membrane potential in 7-day differentiated H9c2 cells after a 12-h incubation. However, energetic pathways were affected in a different manner after MTX or NAPHT incubation. ATP increased and lactate levels decreased after a 24-h incubation with MTX, whereas for the same incubation time and concentrations, NAPHT did not cause any significant effect. The increased activity of ATP synthase seems responsible for MTX-induced increases in ATP levels, as oligomycin (an inhibitor of ATP synthase) abrogated this effect on 5 µM MTX-incubated cells. 3-Methyladenine (an autophagy inhibitor) was the only molecule to give a partial protection against the cytotoxicity produced by MTX or NAPHT. To the best of our knowledge, this was the first broad study on NAPHT cardiotoxicity, and it revealed that the parent drug, MTX, caused a higher disruption in the energetic pathways in a cardiac model in vitro, whereas autophagy is involved in the toxicity of both compounds. In conclusion, NAPHT is claimed to largely contribute to MTX-anticancer properties; therefore, this metabolite should be regarded as a good option for a safer anticancer therapy since it is less cardiotoxic than MTX.


Assuntos
Antineoplásicos/toxicidade , Cardiotoxicidade/etiologia , Mitoxantrona/toxicidade , Miócitos Cardíacos/efeitos dos fármacos , Adenina/análogos & derivados , Adenina/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/metabolismo , Autofagia/efeitos dos fármacos , Cardiotoxicidade/patologia , Linhagem Celular , Relação Dose-Resposta a Droga , Ácido Láctico/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitoxantrona/administração & dosagem , Mitoxantrona/metabolismo , Miócitos Cardíacos/patologia , Quinoxalinas/metabolismo , Quinoxalinas/toxicidade , Ratos , Fatores de Tempo
10.
BMC Infect Dis ; 16(1): 726, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27905897

RESUMO

BACKGROUND: Despite improvements in treatment success rates for tuberculosis (TB), current six-month regimen duration remains a challenge for many National TB Programmes, health systems, and patients. There is increasing investment in the development of shortened regimens with a number of candidates in phase 3 trials. METHODS: We developed an individual-based decision analytic model to assess the cost-effectiveness of a hypothetical four-month regimen for first-line treatment of TB, assuming non-inferiority to current regimens of six-month duration. The model was populated using extensive, empirically-collected data to estimate the economic impact on both health systems and patients of regimen shortening for first-line TB treatment in South Africa, Brazil, Bangladesh, and Tanzania. We explicitly considered 'real world' constraints such as sub-optimal guideline adherence. RESULTS: From a societal perspective, a shortened regimen, priced at USD1 per day, could be a cost-saving option in South Africa, Brazil, and Tanzania, but would not be cost-effective in Bangladesh when compared to one gross domestic product (GDP) per capita. Incorporating 'real world' constraints reduces cost-effectiveness. Patient-incurred costs could be reduced in all settings. From a health service perspective, increased drug costs need to be balanced against decreased delivery costs. The new regimen would remain a cost-effective option, when compared to each countries' GDP per capita, even if new drugs cost up to USD7.5 and USD53.8 per day in South Africa and Brazil; this threshold was above USD1 in Tanzania and under USD1 in Bangladesh. CONCLUSION: Reducing the duration of first-line TB treatment has the potential for substantial economic gains from a patient perspective. The potential economic gains for health services may also be important, but will be context-specific and dependent on the appropriate pricing of any new regimen.


Assuntos
Antituberculosos/economia , Tuberculose/tratamento farmacológico , Tuberculose/economia , Bangladesh , Brasil , Análise Custo-Benefício , Atenção à Saúde/economia , Custos de Medicamentos , Custos de Cuidados de Saúde , Gastos em Saúde , Serviços de Saúde/economia , Humanos , Modelos Teóricos , África do Sul , Tanzânia , Resultado do Tratamento
11.
J Periodontal Res ; 51(6): 689-698, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26774043

RESUMO

BACKGROUND AND OBJECTIVE: Despite investigative efforts to identify the levels of different types of cytokines in the peri-implant crevicular fluid (PICF), the efficacy of these biomarkers in assisting the diagnosis of peri-implantitis is still undetermined. This systematic review aimed to answer the following question: "Could cytokine levels in the PICF be used to distinguish between healthy implants and implants with peri-implantitis?" MATERIAL AND METHODS: This review was conducted and reported in accordance with the PRISMA statement. The MEDLINE and EMBASE databases were searched from 1990 up to and including March 2015, using MeSH terms and other keywords. Additional publications were searched using a hand search of reference lists of relevant studies. Titles and abstracts were screened and papers that fulfilled eligibility criteria were assessed. RESULTS: Out of 1212 titles, 18 studies reporting the levels of nine different cytokines were included. Proinflammatory cytokines [interleukin (IL)-1ß, IL-6, IL-12, IL-17 and tumor necrosis factor-α) were the cytokines studied most commonly, followed by anti-inflammatory cytokines (IL-4 and IL-10), osteoclastogenesis-related cytokines (RANKL) and chemokines (IL-8). Nine studies reported statistically significantly higher levels of proinflammatory cytokines in the PICF of implants with peri-implantitis than in the PICF of healthy implants. Most studies did not find any significant differences in the PICF levels of anti-inflammatory cytokines and RANKL between healthy implants and implants with peri-implantitis. IL-8 was the only chemokine studied and its levels did not differ significantly between healthy and diseased implants. The studies differed greatly in the manner in which they reported the results (e.g. concentrations or total amounts) and in the exclusion of confounders, such as smoking. CONCLUSION: The results of this systematic review indicate moderate evidence in the literature to support that implants with peri-implantitis present higher levels of proinflammatory cytokines in the PICF than do healthy implants. Evidence regarding the PICF levels of anti-inflammatory cytokines, osteoclastogenesis-related cytokines and chemokines as possible predictors of peri-implantitis is too limited.


Assuntos
Citocinas/análise , Implantes Dentários/efeitos adversos , Líquido do Sulco Gengival/química , Peri-Implantite/diagnóstico , Humanos , Peri-Implantite/metabolismo
12.
J Appl Microbiol ; 121(1): 101-14, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26999597

RESUMO

AIMS: The biofilm produced by Staphylococcus aureus isolates involved in clinical or subclinical bovine mastitis and the activity of nisin and lysostaphin against the preformed biofilm produced by these strains were investigated. METHODS AND RESULTS: Eighteen strains were tested and all produced biofilm. Eight strains with distinct biofilm composition were selected for the antimicrobial activity assays. The minimal inhibitory concentration of each bacteriocin was determined against the planktonic cells and ranged from 15·6 to 500 µg ml(-1) for nisin, and from 3·9 to 50 µg ml(-1) , for lysostaphin. Lysostaphin treatment (0·4 µg ml(-1) ) for 4 h caused a strong Staph. aureus 4181 biofilm detachment and death of the majority of the sessile cells, while nisin treatment (100 µg ml(-1) ) for the same time caused only a great reduction in cell viability. Additionally, combination of both bacteriocins for 4 h resulted in significant death of the sessile cells but no biofilm detachment. CONCLUSIONS: The treatment with lysostaphin alone or in combination with nisin was effective in killing most biofilm sessile cells. SIGNIFICANCE AND IMPACT OF THE STUDY: The action of lysostaphin, either alone or in combination with nisin, against established staphylococcal biofilm may represent an alternative to bovine mastitis control. However, the duration of the treatment should be considered for its application so that the best effectiveness can be achieved.


Assuntos
Biofilmes/efeitos dos fármacos , Lisostafina/farmacologia , Mastite Bovina/tratamento farmacológico , Nisina/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Lisostafina/uso terapêutico , Testes de Sensibilidade Microbiana/métodos , Nisina/uso terapêutico , Plâncton/efeitos dos fármacos , Staphylococcus aureus/fisiologia
13.
J Appl Microbiol ; 121(2): 435-44, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27225974

RESUMO

AIMS: The aim of this study was to investigate the potential of aureocin A53, a staphylococcal antimicrobial peptide, for improving food safety. METHODS AND RESULTS: The antimicrobial activity of aureocin A53 against strains of Listeria monocytogenes isolated from food was tested and the bacteriocin proved to be bactericidal and bacteriolytic against the listerial strains. Aureocin A53 was neither toxic to eukaryotic cell lines nor haemolytic against sheep erythrocytes. It also exhibited a remarkable stability during storage at different temperatures and sensitivity to both simulated gastric juice and bile salts. When the antibacterial activity of aureocin A53 (256 AU ml(-1) ) was tested in skimmed milk artificially inoculated with a L. monocytogenes strain (1·0 × 10(4)  CFU ml(-1) ) isolated from food, during storage at 4°C, the bacteriocin reduced the viable counts by 7·7-log10 units up to 7 days of incubation, when compared with the controls not treated with the bacteriocin. CONCLUSIONS: Aureocin A53 exhibited several features considered important for biopreservation and remained fully active in a food matrix. SIGNIFICANCE AND IMPACT OF THE STUDY: Taken together, the results confirmed that aureocin A53 has potential to be used as a food preservative, representing an alternative to the use of nisin in biopreservation of dairy products.


Assuntos
Antibacterianos/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Leite/microbiologia , Peptídeos/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos , Conservação de Alimentos/instrumentação , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/isolamento & purificação , Ovinos
14.
Biofouling ; 32(9): 1007-16, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27552663

RESUMO

The indiscriminate use of biocides for general disinfection has contributed to the increased incidence of antimicrobial tolerant microorganisms. This study aims to assess the potential of seven phytochemicals (tyrosol, caffeic acid, ferulic acid, cinnamaldehyde, coumaric acid, cinnamic acid and eugenol) in the control of planktonic and sessile cells of Staphylococcus aureus and Escherichia coli. Cinnamaldehyde and eugenol showed antimicrobial properties, minimum inhibitory concentrations of 3-5 and 5-12 mM and minimum bactericidal concentrations of 10-12 and 10-14 mM against S. aureus and E. coli, respectively. Cinnamic acid was able to completely control adhered bacteria with effects comparable to peracetic acid and sodium hypochlorite and it was more effective than hydrogen peroxide (all at 10 mM). This phytochemical caused significant changes in bacterial membrane hydrophilicity. The observed effectiveness of phytochemicals makes them interesting alternatives and/or complementary products to commonly used biocidal products. Cinnamic acid is of particular interest for the control of sessile cells.


Assuntos
Anti-Infecciosos/farmacologia , Desinfetantes/farmacologia , Escherichia coli/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Anti-Infecciosos/química , Aderência Bacteriana/efeitos dos fármacos , Desinfetantes/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos Fitoquímicos/química , Soluções
15.
Oral Dis ; 22(4): 280-4, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26748973

RESUMO

OBJECTIVE: We have analysed the association of the +24T>C polymorphism (rs3813946) in CR2, the cellular receptor for Epstein-Barr virus (EBV), in the susceptibility for the development of nasopharyngeal carcinoma (NPC). METHODS: A retrospective case-control study was developed with peripheral blood samples from 111 individuals with NPC and 608 healthy individuals (controls) from the North region of Portugal. The genotyping analysis was performed by allelic discrimination real-time PCR using a TaqMan(®) SNP Genotyping Assay. RESULTS: The genotype distribution was 62.2% TT, 34.2% TC and 3.6% CC for NPC patients; and 65.0%, 30.6% and 4.4%, respectively, for controls. Our study showed no statistical association between the genotype distribution in controls and all types of NPC (P = 0.717); nevertheless, the analysis showed statistically significant differences (P = 0.038) regarding cases with well- or moderately differentiated types of NPC suggesting that +24CC/CT genotypes are associated with increased risk (OR = 4.16; 95% CI 1.28-15.7; P = 0.016). CONCLUSIONS: This is the first study in Western populations to characterize the association of the CR2 +24T>C polymorphism in NPC development, and our results suggest that more studies are required to clarify the impact on NPC susceptibility in different populations.


Assuntos
Regiões 5' não Traduzidas , Carcinoma/genética , Carcinoma/patologia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Receptores de Complemento 3d/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Feminino , Genótipo , Herpesvirus Humano 4 , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Polimorfismo de Nucleotídeo Único , Portugal , Estudos Retrospectivos , Adulto Jovem
16.
J Appl Toxicol ; 36(1): 121-30, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25900438

RESUMO

Abuse of synthetic drugs is widespread worldwide. Studies indicate that piperazine designer drugs act as substrates at dopaminergic and serotonergic receptors and/or transporters in the brain. This work aimed to investigate the cytotoxicity of N-benzylpiperazine, 1-(3-trifluoromethylphenyl)piperazine, 1-(4-methoxyphenyl)piperazine and 1-(3,4-methylenedioxybenzyl)piperazine in the differentiated human neuroblastoma SH-SY5Y cell line. Cytotoxicity was evaluated after 24 h incubations through the MTT reduction and neutral red uptake assays. Oxidative stress (reactive oxygen and nitrogen species production and glutathione content) and energetic (ATP content) parameters, as well as intracellular Ca(2+), mitochondrial membrane potential, DNA damage (comet assay) and cell death mode were also evaluated. Complete cytotoxicity curves were obtained after 24 h incubations with each drug. A significant decrease in intracellular total glutathione content was noted for all the tested drugs. All drugs caused a significant increase of intracellular free Ca(2+) levels, accompanied by mitochondrial hyperpolarization. However, ATP levels remained unchanged. The investigation of cell death mode revealed a predominance of early apoptotic cells. No genotoxicity was found in the comet assay. Among the tested drugs, 1-(3-trifluoromethylphenyl)piperazine was the most cytotoxic. Overall, piperazine designer drugs are potentially neurotoxic, supporting concerns on risks associated with the abuse of these drugs.


Assuntos
Drogas Desenhadas/toxicidade , Síndromes Neurotóxicas/etiologia , Piperazinas/toxicidade , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Linhagem Celular Tumoral , Glutationa/metabolismo , Humanos , Técnicas In Vitro , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Neuroblastoma/patologia , Piperazina
17.
Public Health ; 140: 250-257, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27036982

RESUMO

OBJECTIVE: To identify the hidden prevalence of chronic kidney disease (CKD) in hypertensive patients. STUDY DESIGN: Cross-sectional study of individuals with systemic arterial hypertension (SAH) who were registered for primary health care (PHC). METHODS: In total, 293 individuals participated. Data were collected through interviews, as well as biochemical and anthropometric assessments. The CKD-EPI formula was used to identify the occurrence of CKD. Pearson's chi-squared test or Fisher's exact test were used to compare proportions. Prevalence ratios were estimated with a confidence interval of 95% for associations between the explanatory variables and CKD. RESULTS: Most of the individuals assessed were female (74%), elderly (69%), with a low income (90%), low education levels (84%) and overweight (66.9%). A CKD prevalence of 38.6% (95% CI: 33.0-44.2) was found and approximately 14% were at an advanced stage of the disease. Upon comparison of the variables in the different stages of CKD, statistically significant association could be suggested between CKD and age, education, alcohol intake, overweight individuals, cardiovascular risk, abnormal creatinine and abnormal microalbuminuria. When the prevalence ratio was assessed, association could be suggested between CKD and age, and CKD and creatinine. CONCLUSION: The high hidden prevalence of CKD confirms the need to train health professionals involved in the treatment of SAH through PHC, enabling the prevention and diagnosis of CKD in its early stages.


Assuntos
Hipertensão/epidemiologia , Insuficiência Renal Crônica/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Creatinina/sangue , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Atenção Primária à Saúde , Sistema de Registros , Insuficiência Renal Crônica/sangue , Fatores de Risco
18.
J Periodontal Res ; 50(1): 18-27, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24665908

RESUMO

BACKGROUND AND OBJECTIVE: Microbiological and immunological hypotheses have been raised to explain the differences in the clinical manifestations of aggressive periodontitis and chronic periodontitis. However, studies comparing the cytokine/chemokine profiles in gingival crevicular fluid between these two clinical conditions have so far not been compiled. This systematic review aimed to answer the following question: "Do subjects with aggressive periodontitis and chronic periodontitis have a different profile of cytokines/chemokines in the gingival crevicular fluid?" MATERIAL AND METHODS: An electronic database search of MEDLINE/PubMed and Embase was performed from 1990 up to and including August 2013, using MeSH terms and other keywords. Titles and abstracts were screened and the papers that satisfied eligibility criteria were assessed. RESULTS: Of 1954 titles, 17 studies reporting the levels of 21 different cytokines/chemokines were included. Most studies did not find any significant differences in the gingival crevicular fluid levels of cytokines/chemokines between aggressive periodontitis and chronic periodontitis. Some studies demonstrated that the levels of specific proinflammatory and anti-inflammatory cytokines/chemokines were higher (n = 5) and lower (n = 3), respectively, in aggressive periodontitis than in chronic periodontitis. The studies differed in the manner in which they reported the results (e.g. concentrations or total amounts). It was not clear in some studies whether the sample sites from both groups were matched for disease severity. Some studies did not take into account confounders, such as smoking. CONCLUSION: The current weight of evidence is not sufficient to prove that there are distinct gingival crevicular fluid cytokine/chemokine profiles for patients with aggressive periodontitis and chronic periodontitis.


Assuntos
Periodontite Agressiva/imunologia , Quimiocinas/análise , Periodontite Crônica/imunologia , Citocinas/análise , Líquido do Sulco Gengival/imunologia , Líquido do Sulco Gengival/química , Humanos , Mediadores da Inflamação/análise , Interleucinas/análise
19.
J Appl Toxicol ; 34(9): 1023-30, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24105845

RESUMO

Paraquat (PQ) is a widely used, highly toxic and non-selective contact herbicide, which has been associated with central neurotoxic effects, namely the development of Parkinson's disease, but whose effects to the blood-brain barrier (BBB) itself have rarely been studied. This work studied the mechanisms of PQ uptake and efflux in a rat's BBB cell model, the RBE4 cells. PQ is believed to enter cells using the basic or neutral amino acid or polyamine transport systems or through the choline-uptake system. In contrast, PQ efflux from cells is reported to be mediated by P-glycoprotein. Therefore, we evaluated PQ-induced cytotoxicity and the effect of some substrates/blockers of these transporters (such as arginine, L-valine, putrescine, hemicholinium-3 and GF120918) on such cytotoxicity. RBE4 cells were shown to be extremely resistant to PQ after 24 h of exposure; even at concentrations as high as 50 mM approximately 45% of the cells remained viable. Prolonging exposure until 48 h elicited significant cytotoxicity only for PQ concentrations above 5 mM. Although hemicholinium-3, a choline-uptake system inhibitor, significantly protected cells against PQ-induced toxicity, none of the effects were observed for arginine, L-valine or putrescine. Meanwhile, inhibiting the efflux pump P-glycoprotein using GF120918 significantly enhanced PQ-induced cytotoxicity. In conclusion, PQ used the choline-uptake system, instead of the transporters for the basic or neutral amino acids or for the polyamines, to enter RBE4 cells. P-glycoprotein extrudes PQ back to the extracellular medium. However, this efflux mechanism only partially explains the observed RBE4 resistance to PQ.


Assuntos
Herbicidas/toxicidade , Paraquat/toxicidade , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Barreira Hematoencefálica/citologia , Barreira Hematoencefálica/efeitos dos fármacos , Linhagem Celular , Colina/metabolismo , Células Endoteliais/efeitos dos fármacos , Paraquat/farmacocinética , Ratos
20.
Theriogenology ; 218: 239-243, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38359562

RESUMO

The objective of this study was to evaluate the effect of administering injectable progesterone (P4i) before a timed artificial insemination (TAI) protocol on the follicular growth, ovulation, and pregnancy rate of Bos taurus suckled cows. The effect of P4i administration before the TAI on the pregnancy rate (P/AI) was evaluated in 576 suckled Bos taurus cows at 30-90 days postpartum. In addition, the effect of P4i administration before TAI on follicular dynamics was evaluated in subgroup of 401 suckled Bos taurus cows. On Day -10 (D-10), cows were divided into two experimental groups (Control and P4i). In this moment, P4i cows received i.m. 150 mg of injectable long-action progesterone. After that, both experimental groups received a synchronization protocol (Day 0; D0) that consisted of administration i.m. of 2 mg of estradiol benzoate and a progesterone intravaginal insert on D0. On Day 8 (D8), the progesterone insert was removed, and the cows received 500 µg of cloprostenol, 400 IU of eCG, and 1 mg of estradiol cypionate. TAI was performed 48 h after the removal of the progesterone insert. The ultrasound exams were performed in a subgroup of cows on Days 0, 8, 10 and 12 to evaluate the diameter of the largest follicle, rate of follicular growth and risks of single and double ovulation. The pregnancy diagnosis was performed 30 days after TAI in all cows to determine the pregnancy rate. The diameter of the largest follicle, on D10 (P = 0.84), rate of follicular growth (P = 0.14), ovulation rate (P = 0.40) and double ovulation rates (P = 0.23) did not differ between experimental groups. The pregnancy rate was greater in the P4i group [Control 46.2 % (133/288) vs. P4i 55.6 % (160/288); P = 0.03]. The diameter of the largest follicles (LF) on D0 (Control 11.6 ± 0.2 vs. P4i 13.3 ± 0.3) was greater (P = 0.01) in the P4i group. In conclusion, injectable progesterone before the ovulation synchronization protocol increased the diameter of the largest follicle on the D0 and the pregnancy rate in multiparous Bos taurus suckled beef cows.


Assuntos
Ovulação , Progesterona , Gravidez , Feminino , Bovinos , Animais , Progesterona/farmacologia , Folículo Ovariano , Paridade , Estradiol/farmacologia , Fertilidade , Inseminação Artificial/veterinária , Inseminação Artificial/métodos , Sincronização do Estro/métodos
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