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1.
Iran J Vet Res ; 23(1): 18-23, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35782359

RESUMO

Background: Infectious bronchitis virus (IBV) causes severe economic losses worldwide. IBV has a broad tissue distribution with different viral loads in different tissues. Additionally, IBV can induce apoptosis in infected cells. Aims: The present study aimed to evaluate the role of the genetic background of chickens in viral load and the expression level of apoptotic genes in different tissues of two hybrids of commercial broiler chickens (Ross 308 and Cobb 500) challenged with IBV. Methods: Chickens at 21 days of age were nasally challenged with 200 µL of allantoic fluid containing 104 EID50/ml of Iranian variant-2-like IBV (IS/1494). The expression level of apoptotic genes (Fas, FasL, Bax, and Bcl-2) in the tracheal and renal tissues and the amount of viral load in the tracheal, renal, and cloacal swab samples were investigated two, five, and seven days after IBV infection by RT-qPCR assay. Results: The amount of viral load and apoptotic the expression level of apoptotic genes in the tracheal (two and five days after infection) and renal samples (seven days after infection) were significantly higher in the Ross challenged group than in the Cobb challenged group.Furthermore, no difference was observed in the cloaca viral load on sampling days. Conclusion: To our knowledge, this is the first report that evaluated the role of the chickens' genetic background in the amount of viral load and the expression level of apoptotic genes against IBV. Further studies are needed to investigate the pathogenic characteristics of IBV in Ross 308 and Cobb 500 chickens.

2.
Arch Razi Inst ; 77(6): 2097-2104, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-37274897

RESUMO

In recent years, a nanoparticle-based strategy has shown that non-denatured protein toxins can be used to enhance the appropriate immune response. Once the toxin reacts between the nanoparticles and the protein (toxin), it loses its toxicity because it does not attach to its ligand at the cell surface. The results of the nanoparticle and toxin complex show that the nanoparticles facilitate the internal release of the toxin. Clostridium perfringens beta toxin is produced by Clostridium perfringens type B and C, and diarrhea is the most important disease caused in newborn lambs. When beta toxin forms a complex with nanoparticles, the reaction between the toxin and the nanoparticle leads to the formation of a new form of nanoparticle in which the toxin loses its lethality due to its involvement; therefore, it becomes a toxoid. The nanoparticles used in this research are of poly lactic-co-glycolic acid (PLGA) type, one of the most developed biodegradable polymers. This study aimed to isolate and purify Clostridium perfringens beta toxin and produce its complex with PLGA nanoparticles to form a non-toxic structure. In this study, Clostridium perfringens beta toxin type B was isolated using ammonium sulfate precipitation and gel filtration chromatography. Toxin assay was performed in vivo (lethal dose [LD50]) and in vitro by sodium dodecyl sulphate-polyacrylamide gel electrophoresis at each stage, and the quantity of purified toxin was calculated to be 10 mg/ml. Afterward, the beta toxin antigen was used as the basis for the preparation of nanotoxoid candidates with nanoparticle formulation. Moreover, the PLGA polymer and water-oil-water methods were used to fabricate nanoparticles. Under optimal conditions, nanoparticles without antigen with an average size of 100 nm and zeta potential of -23.28 mV, as well as nanoparticles containing antigen with an average size of 120 nm and zeta potential of -18.2 mV, were prepared. When nanoparticles are injected into mice with the beta toxin, the toxin becomes a toxoid with no toxicity effects, and it cannot bind to its receptors and reveal its effects. In this study, the mice showed mild symptoms in one case, and none of them died. The beta and PLGA toxin model could also be applied as a candidate to study the release and immunization of the target animal. In order to achieve antigen regulation using natural polymers, it is recommended to conduct a comparative study between nanoparticles based on natural polymers.


Assuntos
Clostridium perfringens , Polímeros , Animais , Camundongos , Ovinos , Relação Dose-Resposta a Droga , Toxoides
3.
Arch Microbiol ; 200(7): 1009-1016, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29627903

RESUMO

Salmonella is widely distributed throughout the world and can be found in poultry industry, animal breeding centers, food and feedstuffs of all geographical regions. This study was conducted to determine and identify Salmonella serovars isolated from poultry, calves and foodstuffs (poultry and animals products such as egg and meat). A total of one hundred isolates of Salmonella serovars including Salmonella Typhimurium, Salmonella Enteritidis, Salmonella Infantis, Salmonella Gallinarum and Salmonella Pullorum consecutively were subjected to the conventional culture, biochemical and serological assays. The utility of molecular multiplex PCR was investigated to identify and differentiate among five Salmonella serovars which were identified according to the presence of rfbJ, fljB, invA, and fliC genes in S. Typhimurium, sefA, invA and spv genes in Salmonella Enteritidis, fljB, fliC and invA genes in Salmonella Infantis, hut and slgC genes in both Salmonella Gallinarum and Salmonella Pullorum and speC gene specifically in Salmonella Gallinarum. Biochemical assays and serotyping are complicated to directly differentiate between Salmonella Gallinarum and Salmonella Pullorum because of their antigenic similarity. According to the results, Multiplex PCR can be considered as simple, rapid, accurate and useful test to identify and differentiate among Salmonella serovars.


Assuntos
Ovos/microbiologia , Carne/microbiologia , Reação em Cadeia da Polimerase Multiplex/métodos , Salmonella/isolamento & purificação , Animais , Animais Domésticos/microbiologia , Bovinos , Contaminação de Alimentos/análise , Aves Domésticas/microbiologia , Salmonella/classificação , Salmonella/genética , Salmonella enteritidis/classificação , Salmonella enteritidis/genética , Salmonella enteritidis/isolamento & purificação , Salmonella typhimurium/classificação , Salmonella typhimurium/genética , Salmonella typhimurium/isolamento & purificação , Sorogrupo , Sorotipagem
4.
Braz J Microbiol ; 44(2): 643-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24294264

RESUMO

This study aims at evaluating the effects of Zataria multiflora (Z. multiflora) essential oil (EO) on growth, aflatoxin production and transcription of aflatoxin biosynthesis pathway genes. Total RNAs of Aspergillus parasiticus (A.parasiticus) ATCC56775 grown in yeast extract sucrose (YES) broth medium treated with Z. multiflora EO were subjected to reverse transcription- polymerase chain reaction (RT-PCR). Specific primers of nor-1, ver-1, omt-A and aflR genes were used. In parallel mycelial dry weight of samples were measured and all the media were assayed by high-pressure liquid chromatography (HPLC) for aflatoxinB1 (AFB1), aflatoxinB2 (AFB2), aflatoxinG1 (AFG1), aflatoxinG2 (AFG2) and aflatoxin total (AFTotal) production. The results showed that mycelial dry weight and aflatoxin production reduce in the presence of Z. multiflora EO (100 ppm) on day 5 of growth. It was found that the expression of nor-1, ver-1, omt-A and aflR genes was correlated with the ability of fungus to produce aflatoxins on day 5 in YES medium. RT-PCR showed that in the presence of Z.multiflora EO (100 ppm) nor-1, ver-1 and omtA genes expression was reduced. It seems that toxin production inhibitory effects of Z. multiflora EO on day 5 may be at the transcription level and this herb may cause reduction in aflatoxin biosynthesis pathway genes activity.


Assuntos
Aflatoxinas/biossíntese , Antifúngicos/metabolismo , Aspergillus/efeitos dos fármacos , Vias Biossintéticas/efeitos dos fármacos , Lamiaceae/química , Óleos Voláteis/metabolismo , Transcrição Gênica/efeitos dos fármacos , Antifúngicos/isolamento & purificação , Aspergillus/genética , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Vias Biossintéticas/genética , Cromatografia Líquida de Alta Pressão , Perfilação da Expressão Gênica , Óleos Voláteis/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Braz. j. microbiol ; 44(2): 649-655, 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-688596

RESUMO

This study aims at evaluating the effects of Zataria multiflora (Z. multiflora) essential oil (EO) on growth, aflatoxin production and transcription of aflatoxin biosynthesis pathway genes. Total RNAs of Aspergillus parasiticus (A.parasiticus) ATCC56775 grown in yeast extract sucrose (YES) broth medium treated with Z. multiflora EO were subjected to reverse transcription-polymerase chain reaction (RT-PCR). Specific primers of nor-1, ver-1, omt-A and aflR genes were used. In parallel mycelial dry weight of samples were measured and all the media were assayed by high-pressure liquid chromatography (HPLC) for aflatoxinB1 (AFB1), aflatoxinB2 (AFB2), aflatoxinG1 (AFG1), aflatoxinG2 (AFG2) and aflatoxin total (AFTotal) production. The results showed that mycelial dry weight and aflatoxin production reduce in the presence of Z. multiflora EO (100 ppm) on day 5 of growth. It was found that the expression of nor-1, ver-1, omt-A and aflR genes was correlated with the ability of fungus to produce aflatoxins on day 5 in YES medium. RT-PCR showed that in the presence of Z.multiflora EO (100 ppm) nor-1, ver-1 and omtA genes expression was reduced. It seems that toxin production inhibitory effects of Z. multiflora EO on day 5 may be at the transcription level and this herb may cause reduction in aflatoxin biosynthesis pathway genes activity.


Assuntos
Aflatoxinas/biossíntese , Antifúngicos/metabolismo , Aspergillus/efeitos dos fármacos , Vias Biossintéticas/efeitos dos fármacos , Lamiaceae/química , Óleos Voláteis/metabolismo , Transcrição Gênica/efeitos dos fármacos , Antifúngicos/isolamento & purificação , Aspergillus/genética , Aspergillus/crescimento & desenvolvimento , Aspergillus/metabolismo , Vias Biossintéticas/genética , Cromatografia Líquida de Alta Pressão , Perfilação da Expressão Gênica , Óleos Voláteis/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
6.
Braz. j. microbiol ; 40(3): 439-445, Sept. 2009. tab
Artigo em Inglês | LILACS | ID: lil-522463

RESUMO

Disseminated candidiasis is a serious problem in public health that results from the invasion of Candida species, in particular Candida albicans. The aim of this study was to compare the efficacies of Zataria multiflora essential oil and itraconazole in clearing C. albicans from the visceral organs of BALB/c mice suffered from disseminated candidiasis. Zataria multiflora essential oil was extracted using Clevenger-type apparatus and analyzed by gas chromatography mass spectrometry (GC-MS). For clearance experiment, mice (20-25 g, N=8 per group) received essential oil at doses of 30, 48 and 64 mg/kg and itraconazole at dose of 200 mg/kg intraperitoneally (IP) 2 days before and after intravenous inoculation of 0.5×10(6) C. albicans blastospores. The treated animals were sacrificed on day 20, and 0.1 g of the tissue homogenates was plated onto specific media. In GC-Mass, the main components of the essential oil were carvacrol (61.29 percent) and thymol (25.18 percent). The results demonstrated that IP administration of 64 mg/kg of the essential oil had the highest efficacy in reducing C. albicans and produced 39.5, 21.8, 141.5, 174 and 501-fold reductions in mean CFUs per 0.1 gram in Candida infections of the liver, spleen, lungs, brain and kidneys, respectively, compared to positive control. Itraconazole showed significantly more responsiveness than the essential oil at dose of 30 mg/kg in clearing C. albicans from the kidneys (P<0.02), brain (P<0.02) and spleen (P<0.04), and less responsiveness than that of 64 mg/kg in clearing the organism from the brain (P<0.01), lungs (P<0.0005) and kidneys (P<0.0005), whereas no significant difference was observed between this drug and Z. multiflora at dose of 48 mg/kg. These data explain the increased rate of yeast clearance and reduced dissemination to the viscera of Z. multiflora treated mice.


A candidíase disseminada é um problema sério de saúde publica decorrente da invasão por espécies de Candida, e Candida albicans em particular. O objetivo deste estudo foi comparar a eficiência do óleo essencial de Zataria multiflora e itraconazol na remoção de C. albicans das vísceras de camundongos BALB/c com candidíase disseminada. O óleo essencial de Zataria multiflora foi extraído empregando um aparelho do tipo Clevenger e analisado por cromatografia a gás e espectrometria de massa (GC-MS). Para os experimentos de remoção, camundongos (20-25g, n=8 por grupo) receberam óleo essencial nas doses de 30, 48 e 64 mg/kg e itraconazol na dose de 200 mg/kg via intraperitoneal (IP) por dois dias antes e após a inoculação intravenosa de 0,5 x 10(6) blastósporos de C. albicans. Os animais tratados foram sacrificados no vigésimo dia e 0,1g dos tecidos homogeneizados foram semeados em meios específicos. De acordo com o GC-MS, os principais componentes do óleo essencial foram carvacrol (61,29 por cento) e timol (25,28 por cento). Os resultados mostraram que a administração IP de 64 mg/kg de óleo essencial apresentou a eficiência mais alta na redução de C. albicans e resultou na redução de 39,5, 21,8, 141,5, 174 e 501 vezes na contagem média de C. albicans por 0,1g do fígado, baço, pulmões, cérebro e rins, respectivamente, quando comparado ao controle positivo. O itraconazol apresentou redução de C. albicans maior do que o óleo essencial na dose de 30mg/kg nos rins (P<0,02), cérebro (P<0,02) e baço (P<0,04) e menor no cérebro (P<0,01), pulmões (P<0,0005) e rins (P<0,0005) na dose de 64 mg/kg, enquanto não houve diferença entre esse droga e óleo essencial na dose de 48mg/kg. Estes resultados explicam a remoção aumentada de leveduras e a disseminação reduzida para as vísceras de camundongos tratados com Z. multiflora.

7.
Braz J Microbiol ; 40(3): 439-45, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24031384

RESUMO

Disseminated candidiasis is a serious problem in public health that results from the invasion of Candida species, in particular Candida albicans. The aim of this study was to compare the efficacies of Zataria multiflora essential oil and itraconazole in clearing C. albicans from the visceral organs of BALB/c mice suffered from disseminated candidiasis. Zataria multiflora essential oil was extracted using Clevenger-type apparatus and analyzed by gas chromatography mass spectrometry (GC-MS). For clearance experiment, mice (20-25 g, N=8 per group) received essential oil at doses of 30, 48 and 64 mg/kg and itraconazole at dose of 200 mg/kg intraperitoneally (IP) 2 days before and after intravenous inoculation of 0.5 × 10(6) C. albicans blastospores. The treated animals were sacrificed on day 20, and 0.1 g of the tissue homogenates was plated onto specific media. In GC-Mass, the main components of the essential oil were carvacrol (61.29%) and thymol (25.18%). The results demonstrated that IP administration of 64 mg/kg of the essential oil had the highest efficacy in reducing C. albicans and produced 39.5, 21.8, 141.5, 174 and 501-fold reductions in mean CFUs per 0.1 gram in Candida infections of the liver, spleen, lungs, brain and kidneys, respectively, compared to positive control. Itraconazole showed significantly more responsiveness than the essential oil at dose of 30 mg/kg in clearing C. albicans from the kidneys (P<0.02), brain (P<0.02) and spleen (P<0.04), and less responsiveness than that of 64 mg/kg in clearing the organism from the brain (P<0.01), lungs (P<0.0005) and kidneys (P<0.0005), whereas no significant difference was observed between this drug and Z. multiflora at dose of 48 mg/kg. These data explain the increased rate of yeast clearance and reduced dissemination to the viscera of Z. multiflora treated mice.

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