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1.
Parasitol Res ; 123(4): 177, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573559

RESUMO

This study aimed to investigate the presence of ectoparasites and the occurrence of natural infection by Rickettsia spp. and Trypanosoma spp. in bats from Rio Grande do Sul (RS), Brazil. The evaluated animals were obtained from the Instituto de Pesquisas Veterinárias Desidério Finamor, sent by the Centro Estadual de Vigilância Sanitária, to carry out rabies diagnostic tests, during the period from 2016 to 2021. The bats came from 34 municipalities in RS. Of the 109 animals surveyed, 35.8% (39/109) had 385 ectoparasites, with an average of 9.9 parasites per animal. Of these bats, all had insectivorous feeding habits, with 35.9% (14/39) females and 64.1% (25/39) males. The co-parasitism of Chirnyssoides sp., Ewingana inaequalis, and Chiroptonyssus robustipes on Molossus currentium (Mammalia, Chiroptera) was recorded for the first time. All bats surveyed were negative for infection by the protozoan and bacteria. Thus, the expansion of the occurrence of these ectoparasites in insectivorous bats in RS was observed. Furthermore, this study corresponds to the first recorded interspecific associations for the species.


Assuntos
Quirópteros , Rickettsia , Trypanosoma , Animais , Feminino , Masculino , Brasil/epidemiologia
2.
Comp Immunol Microbiol Infect Dis ; 108: 102158, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38513385

RESUMO

Leptospirosis is a disease caused by Leptospira spp. responsible for considerable impacts on the public and animal health. In the past two decades, non-domesticated species of pets (unconventional pets) have become popular. However, the role of these unconventional pets on maintaining diseases still unclear. Therefore, the objective of this study was to survey the presence of Leptospira spp. DNA in unconventional pets. Samples of kidney tissues from 29 animals belonging to the Mammalia class (including Orders Carnivora, Lagomorpha and Rodentia) were analyzed for the presence of the gene lipL32. As a result, DNA of pathogenic Leptospira spp. from specie L. interrogans was detected in four (13,80%) of the analyzed samples: three from Oryctolagus cuniculus and one from Mesocricetus auratus. This study highlights the importance of epidemiological surveillance of leptospirosis, as it identified in species of unconventional pets, that may possibly act as reservoirs of Leptospira spp.


Assuntos
Leptospira , Leptospirose , Doenças dos Roedores , Animais , Coelhos , Leptospira/genética , Doenças dos Roedores/epidemiologia , Leptospirose/epidemiologia , Leptospirose/veterinária , Roedores , DNA Bacteriano/genética
3.
Braz J Microbiol ; 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37999913

RESUMO

This study sought to evaluate the in vitro and ex vivo susceptibility of Pythium insidiosum to ozonized sunflower oil (OSO) and verify the morphological alterations of OSO-exposed hyphae. Susceptibility assays were performed according to the broth microdilution protocol M38-A2/CLSI, and the minimal inhibitory (MIC) and minimal oomicidal (MOC) concentrations were also determined. Non-ozonated sunflower oil (SO) was used as the oil control. Additionally, kunkers from equine pythiosis were exposed to OSO. Damages caused by OSO and SO on P. insidiosum hyphae ultrastructure were verified using scanning electron microscopy. The MIC range for OSO was 7000 to 437.5 mg/mL, and the values for SO were higher, ranging from 56000 to 14000 mg/mL. The MOC was equal to MIC for both oil formulations. The OSO fully inhibited the oomycete growth from kunkers, although there was P. insidiosum growth in the kunker control in 24 h of incubation. The SEM analyses showed that both OSO and SO caused morphological alterations in P. insidiosum hyphae, highlighting the presence of cavitation along the hyphae with loss of continuity of the cell wall, which was more evident in the OSO-treated hyphae. The OSO had the best oomicidal activity, leading us to believe that our findings may support future research containing this formulation to be applied in integrative medicine protocols to control pythiosis in animals and humans.

4.
Parasitol Res ; 122(7): 1605-1619, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37154922

RESUMO

Leishmaniasis is a zoonosis caused by protozoan species of the genus Leishmania. It generates different clinical manifestations in humans and animals, and it infects multiple hosts. Leishmania parasites are transmitted by sandfly vectors. The main objective of this systematic review was to identify the host, or reservoir animal species, of Leishmania spp., with the exception of domestic dogs, that were recorded in Brazil. This review included identification of diagnostic methods, and the species of protozoan circulating in the country. For this purpose, a literature search was conducted across index journals. This study covered the period from 2001 to 2021, and 124 studies were selected. Eleven orders possible hosts were identified, including 229 mammalian species. Perissodactyla had the highest number of infected individuals (30.69%, 925/3014), with the highest occurrence in horses. In Brazil, the most commonly infected species were found to be: horses, domestic cats, rodents, and marsupials. Bats, that were infected by one or more protozoan species, were identified as potential reservoirs of Leishmania spp. Molecular tests were the most commonly used diagnostic methods (94 studies). Many studies have detected Leishmania spp. (n = 1422): Leishmania (Leishmania) infantum (n = 705), Leishmania (Viannia) braziliensis (n = 319), and Leishmania (Leishmania) amazonensis (n = 141). Recognizing the species of animals involved in the epidemiology and biological cycle of the protozoan is important, as this allows for the identification of environmental biomarkers, knowledge of Leishmania species can improve the control zoonotic leishmaniasis.


Assuntos
Reservatórios de Doenças , Leishmaniose , Animais , Gatos , Cães , Humanos , Brasil/epidemiologia , Reservatórios de Doenças/parasitologia , Leishmaniose/diagnóstico , Leishmaniose/epidemiologia , Leishmaniose/parasitologia , Leishmaniose/prevenção & controle , Leishmania , Zoonoses/epidemiologia , Zoonoses/parasitologia , Zoonoses/prevenção & controle , Mamíferos/parasitologia , Especificidade de Hospedeiro
5.
Parasitol Res ; 122(7): 1677-1683, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37212834

RESUMO

The objective of this study was to evaluate the effectiveness of live attenuated commercial vaccine LIVACOX® T against avian coccidiosis upon parasite exposure through its correlation with productive and economic performance, clinical observation, and oocyst excretion of broiler chickens. For this purpose, 420 1-day-old Cobb chicks were divided into five groups of 84 birds: (G1) unvaccinated and unchallenged control; (G2) vaccinated on day 0; (G3) challenged on day 1; (G4) vaccinated on day 0 and challenged on day 14; and (G5) challenged on day 14. For 28 days, the clinical signs of infection, weight and feed conversion of the birds, and excretion of oocysts in the feces were evaluated. Macroscopic analysis of intestinal lesions in birds was also performed. After vaccination in G2, G3, and G4 as well as after challenge in G3, G4, and G5, there was an increase in oocyst excretion. In the analysis of weight gain, the difference in final weight between groups G3 and G4 is - 105.74 g per bird. Therefore, if we multiply this value by the average number of birds slaughtered per day in a medium/large slaughterhouse (250,000), we have 26,435 kg of chicken meat per day of slaughter, representing 581,570 kg of monthly losses (22 days of slaughter/month), or approximately R$3,489,420.00 (US$872,355.00), considering the commercial value at R$6.00/kg (US$ 1.5/kg). Thus, the productive and economic impact of coccidiosis in broiler chickens is evident, and the importance of vaccination to prevent the occurrence of the disease and reduce subsequent loss is highlighted.


Assuntos
Coccidiose , Doenças das Aves Domésticas , Vacinas Protozoárias , Animais , Galinhas/parasitologia , Vacinas Atenuadas , Coccidiose/prevenção & controle , Coccidiose/veterinária , Intestinos/patologia , Oocistos , Vacinação/veterinária , Doenças das Aves Domésticas/parasitologia
6.
Fungal Biol ; 127(4): 969-974, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37024156

RESUMO

Pythium insidiosum causes pythiosis, an infection that affects different species of mammals, including humans, and inhabits marshy ecosystems of tropical, subtropical, and temperate regions worldwide. Therefore, this study proposes a protocol to expose Culex quinquefasciatus to P. insidiosum zoospores. Cx. quinquefasciatus immatures (eggs, larvae, and pupae) were exposed to zoospores (8x103 zoospores/mL) of the oomycete for 24 h. The exposure of Cx. quinquefasciatus to the zoospores from L1 to the emergence of adults was evaluated, and P. insidiosum detection was performed by microbiological culture, polymerase chain reaction, and histopathological analysis of stage 4 larvae. The protocol used to produce Cx. quinquefasciatus colonies and adapted for this study proved viable for research on the interaction between P. insidiosum and this Culicidae species. Moreover, P. insidiosum presence was evident in all larval stages of the mosquito, although the presence of the oomycete was not detected in the eggs, pupae, and adults. This study is a pioneer in the development of a protocol to evaluate Cx. quinquefasciatus exposure to P. insidiosum zoospores, and under experimental conditions, P. insidiosum can establish itself in Cx. quinquefasciatus larval stages. The developed protocol is expected to serve as a basis for developing studies to evaluate the interactions of P. insidiosum with these mosquitoes and shed more light on the participation of culicids in expanding the ecological niche of P. insidiosum.


Assuntos
Culex , Culicidae , Pitiose , Pythium , Humanos , Animais , Ecossistema , Pitiose/microbiologia , Larva , Mamíferos
7.
Acta Parasitol ; 68(2): 447-452, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36884141

RESUMO

PURPOSE: The clinical progression of Leishmania (Leishmania) amazonensis infection depends on multiple factors, including immunological status of the host and their genotypic interaction. Several immunological processes depend directly on minerals for an efficient performance. Therefore, this study used an experimental model to investigate the alterations of trace metals in L. amazonensis infection associate with clinical outcome, parasite load, and histopathological lesions, and the effect of CD4 + T cells depletion on these parameters. METHODS: A total of 28 BALB/c mice were divided into 4 groups: 1-non-infected; 2-treated with anti-CD4 antibody; 3-infected with L. amazonensis; and 4-treated with anti-CD4 antibody and infected with L. amazonensis. After 24 weeks post-infection, levels of calcium (Ca), iron (Fe), magnesium (Mg), manganese (Mn), Cu, and Zn were determined by inductively coupled plasma optical emission spectroscopy using tissue samples of the spleen, liver, and kidneys. Additionally, parasite burdens were determined in the infected footpad (inoculation site) and samples of inguinal lymph node, spleen, liver, and kidneys were submitted to histopathological analysis. RESULTS: Despite no significant difference was observed between groups 3 and 4, L. amazonensis-infected mice had a significant reduction of Zn (65.68-68.32%) and Mn (65.98 to 82.17%) levels. Presence of L. amazonensis amastigotes was also detected in the inguinal lymph node, spleen, and liver samples in all infected animals. CONCLUSION: The results showed that significant alterations in micro-elements levels occur in BALB/c mice experimentally infected with L. amazonensis and may increase the susceptibility of individuals to the infection.


Assuntos
Leishmania , Leishmaniose Cutânea , Camundongos , Animais , Leishmaniose Cutânea/parasitologia , Manganês , Zinco , Camundongos Endogâmicos BALB C
8.
Vet Res Commun ; 47(3): 1749-1751, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36598644

RESUMO

Cattle are the main hosts of Rhipicephalus microplus; however, this ixodid can also parasitize other animal species. We collected a specimen of R. microplus larvae from one bat Molossus rufus (Mammalia, Chiroptera) from the Cachoeirinha municipality (29° 56' 52'' S and 51° 5' 43'' W), Rio Grande do Sul, Brazil. The specimen was taxonomically identified using identification keys (Vargas 2006). This study reports the first occurrence of this species parasitizing insectivorous bats in Brazil.


Assuntos
Quirópteros , Rhipicephalus , Bovinos , Animais , Larva , Brasil
9.
Microb Pathog ; 174: 105950, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36528325

RESUMO

Prototheca bovis has been associated with several cases of mastitis in cattle but no record of intramammary infections has been reported in goats. This infection does not respond to available treatments and the disposal recommendation of affected animals cause great damage to the dairy industry. Alternatives for dealing with infections caused by Prototheca spp. are required worldwide. In vitro results suggest polypyrrole as promising molecule for combating this alga, because an algaecide effect was observed on tested Prototheca spp. isolates. Thus, this study evaluated goats as an experimental model for intramammary infection by P. bovis and a protocol for treating these animals with an intramammary polypyrrole solution. The possibility of P. bovis promoting an intramammary infection in goats was experimentally proven, demonstrating this species as an important model for studies involving algae mastitis. Furthermore, polypyrrole reduced the counts of Prototheca sp. in the analyzed samples, showing potential to fight this microorganism also in vivo. The results obtained in this study demonstrate the ability of P. bovis to colonize breast tissue in lactating goats and the highly soluble molecule of polypyrrole has potential use for the treatment of protothecosis.


Assuntos
Mastite Bovina , Prototheca , Feminino , Animais , Bovinos , Humanos , Polímeros/uso terapêutico , Lactação , Pirróis/uso terapêutico , Cabras , Mastite Bovina/tratamento farmacológico
10.
Braz J Microbiol ; 53(4): 2233-2240, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36205841

RESUMO

Leptospirosis is an infectious disease caused by Leptospira spp. and affects animals and humans. Reports of leptospirosis in bats have increased and prompted epidemiological research in Brazil. This study aimed to perform a molecular and epidemiological investigation of pathogenic Leptospira spp. in bat kidneys. The total DNA was extracted from 102 kidney samples from chiropterous of different species and cities in Rio Grande do Sul State (RS), Brazil. The polymerase chain reaction was used to amplify a fragment corresponding to lipL32 gene, which is only present in pathogenic Leptospira spp. lipL32 gene was detected in 22.5% (23/102) of the bat kidney tissues. Phylogenetic analysis showed that L. interrogans is circulating in bats in RS. Most species of the bats collected were insectivores. Pathogenic Leptospira spp. detection in bats demonstrated that these animals participate in the infection chain of leptospirosis and, therefore, may play as reservoirs and disseminators of this microorganism. Thus, it is important to monitor infectious agents, especially with zoonotic potential in bats.


Assuntos
Quirópteros , Leptospira interrogans , Leptospira , Leptospirose , Animais , Humanos , Quirópteros/microbiologia , Filogenia , Leptospira interrogans/genética , Brasil/epidemiologia , Leptospira/genética , Leptospirose/epidemiologia , Leptospirose/veterinária , Leptospirose/microbiologia
11.
Arch Microbiol ; 204(11): 680, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36315293

RESUMO

Bovine mastitis is an important disease in dairy cows, and Staphylococcus aureus is the most prevalent microorganism. Bacteriophages are considered an alternative to treat bacterial infections due to antimicrobial resistance crisis. In this study, we isolated and characterized novel S. aureus temperate phages, namely B_UFSM4 and B_UFSM5, from bovine milk. The complete genomes of B_UFSM4 and B_UFSM5 have 41.396 bp and 41.829 bp, respectively. The viruses have double-stranded DNA and linear architecture. Phylogenic similarity was observed by proteome with Staphylococcus phage phiPV83, CN125 and JS01. Therefore, the phages were classified into the family Siphoviridae, genus Biseptimavirus and order Caudovirales. In the host range, the B_UFSM4 and B_UFSM5 had lytic activity of 45.8% and 54.16%, respectively, inclusive on isolates from Staphylococcus sciuri and Rothia terrae. Thus, in this study, species novel of S. aureus temperate phages was isolated and characterized, these phages reveal similarities to each other; however, they are distinct from other species of S. aureus phages of the family Siphoviridae.


Assuntos
Mastite Bovina , Siphoviridae , Infecções Estafilocócicas , Animais , Feminino , Bovinos , Staphylococcus aureus/genética , Leite/microbiologia , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Fagos de Staphylococcus/genética , Mastite Bovina/microbiologia , Siphoviridae/genética
12.
Parasitol Res ; 121(11): 3269-3273, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36121564

RESUMO

In Brazil, visceral leishmaniasis (VL) has been expanding and urbanizing, mainly in non-endemic areas such as the State of Rio Grande do Sul. Considering that infected dogs are the main reservoirs of VL in urban areas, the present study aimed to evaluate the propagation of canine visceral leishmaniasis (CVL) infection from an unaffected region in transition to a VL transmission area. For this, 1159 and 1087 samples of canine serum from 2015 and 2021, respectively, were analyzed, using the indirect immunofluorescence test. In addition, necropsy reports between 2007 and 2021 were evaluated. The results showed a prevalence of anti-Leishmania spp. antibodies of 7.5% in the samples from 2015, while in 2021 samples, it was 23.5%, with an incidence of 0.4 cases per 100 dogs. It is noteworthy that in 2007, there was no record of CVL as the cause of death in the pathological reports, and in 2021, 41 diagnoses were made with the protozoan being a determinant of the death of the animal. These values indicate an increasing trend in the prevalence and incidence coefficients of CVL. The results of this study allowed us to verify the spread of the disease from an unaffected region to a transmission area of the agent, as well as provide subsidies for health authorities to implement improvements in the CVL control program in the municipality, to mitigate the emergence of human cases of the disease.


Assuntos
Doenças do Cão , Leishmania infantum , Leishmania , Leishmaniose Visceral , Leishmaniose , Animais , Brasil/epidemiologia , Doenças do Cão/diagnóstico , Cães , Humanos , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária
13.
Parasitol Res ; 121(11): 3327-3330, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36109382

RESUMO

Sand flies are hematophagous dipterans and are considered vectors of the parasites belonging to the genus Leishmania, which can infect mammals, including humans, and subsequently cause leishmaniasis. Rio Grande do Sul State (RS), southern Brazil, was considered free of this disease for the last few decades. However, several autochthonous cases of visceral leishmaniasis (VL) have been recorded in different municipalities in recent years. Since 2017, cases of canine visceral leishmaniasis (CVL) have been reported in the municipality of Santa Maria, located in the central region of RS. In 2021, two cases of human VL were confirmed in the city, resulting in one death. To capture the possible vectors involved in the disease transmission cycle, Centers for Disease Control (CDC) modified light traps were installed in the peridomestic residential areas. These points were situated in two city districts where cases of CVL had been reported from January 2021 to January 2022. In the 41 sample collections of sand flies, 9 specimens of Lutzomyia longipalpis were identified, confirming the municipality as an area of VL transmission, according to Brazilian sanitary standards. The spread of Leishmania spp. has been occurring efficiently, resulting in a negative impact on the One Health. This study reports the first detection of L. longipalpis in the central region of RS.


Assuntos
Leishmania , Leishmaniose Visceral , Leishmaniose , Psychodidae , Animais , Brasil/epidemiologia , Cães , Humanos , Leishmaniose Visceral/parasitologia , Mamíferos , Psychodidae/parasitologia
14.
Parasitol Res ; 121(11): 3193-3202, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36048268

RESUMO

This study aimed to detect the occurrence of infection by Leishmania spp.in bats from 34 municipalities of Rio Grande do Sul state (RS; southern Brazil) from 2016 to 2021. A total of 109 bats were provided by the Centro Estadual de Vigilância em Saúde of RS, including six species belonged to Molossidae family, six to Vespertilionidae family, and two to Phyllostomidae family. Leishmania spp. was identified using the nested-PCR method by amplifying the SSU rDNA ribosomal subunit gene into four organ pools: (1) the liver, spleen, and lymph node; (2) heart and lungs; (3) skin; and (4) bone marrow of each bat. Three (3/109, 2.7%) animals tested positive for Leishmania spp. The respective PCR-positive organs came from pools 1 and 3. Two bats (Tadarida brasiliensis) were from the municipality of Canoas, and sequences analysis confirms the species identification as Leishmania infantum. In the third bat (Molossus molossus), from Rio Grande, it was not possible to determine the protozoa species, being considered Leishmania spp. Our results indicate that bats can participate in the biological cycle of Leishmania spp. and perform as host, reservoir, and/or source of infection of the protozoa in different areas of RS. More studies will be needed to elucidate the role of these Chiropteras in the circulation of Leishmania spp. This is the first study reporting the occurrence of Leishmania spp. in bats in Rio Grande do Sul state, southern Brazil.


Assuntos
Quirópteros , Leishmania infantum , Animais , Brasil/epidemiologia , Quirópteros/parasitologia , DNA Ribossômico/genética , Leishmania infantum/genética , Prevalência
15.
Braz J Microbiol ; 53(3): 1715-1721, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35352318

RESUMO

This study aimed to guide professionals working in veterinary laboratories, outpatient clinics, medical centers, and hospitals regarding the biosafety measures that should be adopted during the novel coronavirus (SARS-CoV-2) pandemic. While the population is not yet fully immunized by vaccines, the adoption of biosafety measures is essential to control the spread of circulating strains of the new coronavirus. Thus, the importance of professionals and collaborators following biosafety guidelines in different veterinary work environments is highlighted. The main protocols on biosafety to be adopted include frequent handwashing with water and soap or using 70% alcohol-based hand sanitizers, using personal protective equipment (PPE) (including gloves, lab coat, face mask), avoiding the contact of the hands with mucous membranes (eyes, nose and mouth), not sharing personal objects, keeping environments clean and well ventilated, social distancing of 1.5 m between individuals, and maintaining objects and surfaces regularly clean throughout the work environment. The transformation of work processes, such as various biosafety practices, is necessary within the context of the COVID-19 pandemic and improves the safety of professionals in their work environment and other people and animals, decreasing contamination risks in order to reduce the spread of this viral agent.


Assuntos
COVID-19 , SARS-CoV-2 , Instituições de Assistência Ambulatorial , Animais , COVID-19/epidemiologia , COVID-19/prevenção & controle , Contenção de Riscos Biológicos , Hospitais Veterinários , Humanos , Laboratórios , Pandemias/prevenção & controle
16.
Braz J Microbiol ; 53(2): 1011-1017, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35239152

RESUMO

Essential oils (EO) are aromatic compounds from the plant secondary metabolism. Melaleuca alternifolia EO is well known for its medicinal properties and promising use as an antimicrobial agent. Pythiosis is a difficult-to-treat and emerging disease caused by the oomycete Pythium insidiosum. This study evaluated a nanoemulsion formulation of M. alternifolia (NEMA) in topical and intralesional application to treat experimental pythiosis. Dermal toxicity tests were performed on M. alternifolia EO in Wistar rats. Pythiosis was reproduced in rabbits (n = 9) that were divided into groups: group 1 (control), cutaneous lesions with daily topical application of a non-ionizable gel-based formulation and intralesional application of sterile distilled water every 48 h; group 2 (topical formulation), lesions treated daily with topical application of a non-ionizable gel-based formulation containing 5 mg/ml of NEMA; and group 3 (intralesional formulation), lesions treated with NEMA at 5 mg/ml in aqueous solution applied intralesionally/48 h. The animals were treated for 45 days, and the subcutaneous lesion areas were measured every 5 days. M. alternifolia EO showed no dermal toxicity. The lesion areas treated with intralesional NEMA reduced at the end of treatment, differing from groups 1 and 2 (P < 0.05). In the topically treated group, the lesion areas did not differ from the control group, although the number of hyphae significantly reduced (P < 0.05). Under the experimental conditions of this study, the NEMA formulations presented a favorable safety profile. However, further studies are required to evaluate if this safety applies to higher concentrations of NEMA and to validate its use in clinical pythiosis.


Assuntos
Melaleuca , Óleos Voláteis , Pitiose , Pythium , Animais , Pitiose/tratamento farmacológico , Pitiose/microbiologia , Coelhos , Ratos , Ratos Wistar
17.
Med Mycol ; 57(7): 858-863, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30597067

RESUMO

Pythium insidiosum belongs to the phylum Oomycota. It is capable of infecting mammals causing a serious condition called pythiosis, which affects mainly horses in Brazil and humans in Thailand. The objective of the present study was to verify the in vitro anti-P. insidiosum activity of a biogenic silver nanoparticle (bio-AgNP) formulation. The in vitro assays were evaluated on P. insidiosum isolates (n = 38) following the M38-A2 protocol. Damage to the P. insidiosum hyphae ultrastructure was verified by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Bio-AgNP inhibition concentrations on P. insidiosum isolates ranged from 0.06 to 0.47 µg/ml. It was observed through SEM that P. insidiosum hyphae treated showed surface roughness, as well as cell walls with multiple retraction areas, loss of continuity, and rupture in some areas. The TEM of treated hyphae did not differentiate organelle structures; also, the cellular wall was rarefied, showing wrinkled and partly ruptured borders. The bio-AgNP evaluated has excellent in vitro anti-P. insidiosum activity. However, further studies on its in vivo action are necessary as so to determine the possibility of its use in the treatment of the disease in affected hosts.


Assuntos
Antifúngicos/farmacologia , Hifas/efeitos dos fármacos , Nanopartículas Metálicas/química , Pythium/efeitos dos fármacos , Prata/farmacologia , Hifas/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
18.
Parasitol Res ; 117(3): 713-720, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29374783

RESUMO

This study describes experimental infection of guinea pigs (Cavia porcellus) infested with naturally infected Amblyomma ovale nymphs with Rickettsia sp. (Atlantic rainforest strain), and the capacity of A. ovale nymphs to transmit this bacterium. Twenty-six guinea pigs were divided into the following groups: G1, 10 animals infested with uninfected A. ovale nymphs; G2, 10 animals infested with nymphs infected with Rickettsia sp. (Atlantic rainforest strain); and G3, 6 animals without tick infestation. Blood samples were taken 7, 14, 21, and 28 days post-infestation for serological and hematological tests. For histopathological analysis and rickettsial DNA detection, fragments of the spleen, lung, brain, and liver were harvested after euthanasia. The average feeding period for nymphs was 6.6 days for G1 and 6 days for G2. Hemolymph and PCR assays, performed to detect the causative agent in ticks, indicated that in G1, all ticks were negative, and in G2, all nymphs were positive by PCR and 80% (8/10) was positive by hemolymph tests. The only clinical change was skin scarring at the tick attachment site. Hematological parameters indicated leukopenia and total plasma protein (TPP) increased with decreased platelets in G1. In G2, leukocytosis, neutrophilia, monocytosis, an increase in platelets, and reduced TPP were observed. Only G2 guinea pigs were seroconverted (80%; 8/10). Histopathology tests indicated mild, diffuse hemosiderosis and mild, multifocal, follicular hyperplasia in the spleen. Molecular analysis did not detect Rickettsia sp. DNA in C. porcellus tissues. We demonstrated the capacity of A. ovale nymphs to transmit Rickettsia sp. (Atlantic rainforest strain) to guinea pigs.


Assuntos
Ixodidae/microbiologia , Infecções por Rickettsia/veterinária , Infestações por Carrapato/veterinária , Animais , Cobaias , Ninfa , Reação em Cadeia da Polimerase , Floresta Úmida , Rickettsia/genética , Infecções por Rickettsia/microbiologia , Infecções por Rickettsia/transmissão , Infestações por Carrapato/complicações
19.
Parasitol Res ; 116(11): 2911-2919, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28861619

RESUMO

This study evaluated the efficacy and the economic viability of two anticoccidial treatment regimens tested in lambs naturally exposed to Eimeria spp. re-infections in a grazing system during a 140-day period. Twenty-four suckling lambs were distributed into three groups based on the individual count of oocysts per gram of feces (OPG) and body weight. Animals were treated with toltrazuril 5% (20 mg/kg) at 14- (GI) or 21-day (GII) intervals, and GIII was kept as untreated control. A cost-benefit analysis of each treatment regimen was calculated. Additionally, economic analysis was performed on four hypothetical scenarios, in which lambs could be having 10, 25, 50, or 85% decrease in their expected body weight gain due to clinical. Efficacy of toltrazuril against Eimeria spp. was 96.9-99.9% (GI) and 74.2-99.9% (GII). E. ovinoidalis was most frequently identified, but no clinical signs of coccidiosis were observed in lambs. There were no differences in weight gain among the groups. The cost of treatment per lamb was $13.09 (GI) and $7.83 (GII). The estimation model showed that the cost-benefit ratio favored treatment with toltrazuril when lambs fail to gain weight. In the studied flock, the break-even point for toltrazuril administered at 14-day intervals was reached with 85% decrease in mean weight gain. In conclusion, toltrazuril can be used at 14-day intervals to control Eimeria spp. (re)-infection in lambs raised on pasture. This treatment regimen was not economically feasible for subclinical coccidiosis; however, it may be feasible when used to prevent weight loss caused by clinical coccidiosis.


Assuntos
Coccidiose/veterinária , Coccidiostáticos/uso terapêutico , Eimeria , Doenças dos Ovinos/tratamento farmacológico , Triazinas/uso terapêutico , Administração Oral , Animais , Coccidiose/tratamento farmacológico , Coccidiose/economia , Coccidiostáticos/economia , Análise Custo-Benefício , Fezes , Feminino , Masculino , Oocistos , Ovinos , Doenças dos Ovinos/economia , Triazinas/economia , Aumento de Peso/efeitos dos fármacos
20.
Microb Pathog ; 104: 32-38, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28062289

RESUMO

Chagas disease (CD) is caused by Trypanosoma cruzi, an intracellular protozoan which is a potent stimulator of cell-mediated immunity. In the indeterminate form of CD (IFCD) a modulation between pro- and anti-inflammatory responses establishes a host-parasite adaptation. It was previously demonstrated that purinergic ecto-enzymes regulates extracellular ATP and adenosine levels, influencing immune and inflammatory processes during IFCD. In inflammatory sites ATP, as well as its degradation product, adenosine, function as signaling molecules and immunoregulators through the activation of purinergic receptors. In this work, it was analyzed the gene and protein expression of P2X7 purinergic receptor in peripheral lymphocytes and serum immunoregulatory cytokines from IFCD patients. Gene and protein expression of P2X7 receptor (P2X7R), and serum cytokines (IL-2, IL-10, IL-17 and IFN-γ) were unaltered. However, IFCD group showed significantly higher IL-4 and IL-6 levels while TNF-α was significantly decreased. These results indicate that imune profile of IFCD patients displays anti-inflammatory characteristics, consistent with the establishment of an immunomodulatory response. Further study about the molecular knowledge of P2X7R in IFCD is useful to clarify the participation of purinergic system in the regulatory mechanism which avoid the progression of CD.


Assuntos
Doença de Chagas/genética , Doença de Chagas/imunologia , Expressão Gênica , Imunidade Celular , Linfócitos/imunologia , Linfócitos/metabolismo , Receptores Purinérgicos P2X7/genética , Estudos de Casos e Controles , Doença de Chagas/diagnóstico , Doença de Chagas/parasitologia , Citocinas/metabolismo , Humanos , Imunomodulação , Mediadores da Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Receptores Purinérgicos P2X7/metabolismo
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