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1.
Gene ; 888: 147785, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37689222

RESUMO

Transposable elements (TEs) are mobile repetitive DNA sequences that can transfer horizontally between species. Due to their mutagenic characteristics, TEs are associated with different evolutionary events, including chromosomal rearrangements that are abundant in the beetle Euchroma gigantea. In order to understand more in depth the impact of TEs on the genomic evolution of E. gigantea, we characterized the E. gigantea mobilome and evaluated the horizontal transfer of Tc1-Mariner elements. Genomic sequencing data was generated on the Illumina Hiseq plataform, from a specimen (Northeast lineage) collected in Recife, Pernambuco - Brazil. The TEs were characterized by two independent approaches based on the clustering and assembly of highly repetitive sequences, the RepeatExplorer and dnaPipeTE. The sequences obtained were further characterized using ORFfinder and CD-Search, to obtain the TEs' potential coding proteins and verify the presence and integrity of known TE domains. Evidence for horizontal transfer was evaluated by nucleotide and protein genetic distance between TEs from E. gigantea and other species and phylogenetic incongruences detected between TEs and hosts phylogenetic trees. The mobilome of E. gigantea represents about 21 to 26% of its genome. This mobilome is composed of TEs from 31 superfamilies, belonging to different classes and most known orders of TEs. Several types of TEs with intact domains were observed with emphasis on Tc1-Mariner suggesting the presence of potentially autonomous elements. This superfamily also stands out for having the greatest abundance and diversity, with TEs being classified into four families. When compared to TEs deposited in databases, Mariner TEs stood out as having the highest nucleotide identity (above 90%) with TEs from phylogenetically distant species, such as ants and bees. Altogether these results suggest that E. gigantea Mariner TEs underwent multiple horizontal transfer events to other insect species.


Assuntos
Besouros , Humanos , Animais , Besouros/genética , Filogenia , Elementos de DNA Transponíveis/genética , Genômica , Nucleotídeos , Evolução Molecular
2.
Rev. Fac. Odontol. (B.Aires) ; 38(89): 69-74, 2023. ilus
Artigo em Espanhol | LILACS | ID: biblio-1553303

RESUMO

Objetivo: Evaluar la supervivencia de Streptococcus mutans (S.mutans)en un tipo de fómite. Método: Se reactivó una cepa de S.mutans ATCC25175 criopre-servada en agar TYCSB. El inóculo se estandarizó en PBS buffer hasta obtener turbidez equivalente al 0,5 de Mc Farland y un OD = 0.01 por espectrofotome-tría. Bloques plásticos de 2cm2/superficie fueron seleccionados como fómites. La descontaminación de los bloques se realizó por inmersión en alcohol etílico 70% v/v durante 10 minutos, los que fueron secados en cabina de seguridad biológica. La conta-minación de los mismos se realizó por inmersión en inóculo estandarizado durante 10 minutos. Los blo-ques contaminados se extrajeron y depositaron so-bre placas de Petri estériles hasta cumplir los tiem-pos propuestos (T0-T4 con intervalos de 30 minutos). A cada tiempo, los bloques fueron eluidos en 20 ml de buffer PBS y agitados en vortex durante 30 segun-dos. 100 µl de cada eluato fueron sembrados por dis-persión en agar TYCSB e incubados en anaerobiosis por 48 horas a 37°C. El recuento de colonias (UFC/ml) se realizó bajo lupa estereoscópica 50X. Resulta-dos: El recuento inicial de S.mutans fue de 7,8 X 106(DS+1,7 X 106) UFC/ml y para cada tiempo de estu-dio fue de: T0=3.25 X 104 (DS+1.9 X 103); T1=2.63X104 (DS+4,50E+03); T2= 1.85 X 104 (DS+9,45E+02); T3=1.93 X103(DS+1,29E+03) y T4=1.2X103 (DS+7,21x102). Conclusión: En los rangos de tiempos establecidos, la cepa de S.mutans ensayada permaneció viable sobre la superficie plástica (AU)


Aim: To evaluate the survival time of Streptococcus mutans (S.mutans) in a type of fomites. Method: A strain of cryopreserved S.mutans ATCC 25175 was reactivated in TYCSB agar. The inoculum was standardized in the PBS buffer to obtain turbidity equivalent to 0.5 Mc Farland and OD = 0.01 by spectrophotometry. Plastic blocks of 2 cm2 /surface were selected as fomites. Decontamination of the blocks was carried out for 10 minutes by immersion in ethyl alcohol 70% v/v, which were dried in a biosafety chamber. Contamination was carried out by immersion in standardized inoculum for 10 minutes. The contaminated blocks were extracted and put on sterile Petri dishes until the proposed times were met (T0-T4 at 30-minute intervals). At each time, the blocks were eluted in 20 ml of PBS buffer and vortexed for 30 seconds. 100 µl of each eluate were dispersed on TYCSB agar and incubated anaerobically for 48 hours at 37°C. Colony count (CFU/ml) was performed under a 50X stereoscopic magnifying glass. Results: The initial S.mutans count was 7,8 X 106 (DS+1,7 X 106) CFU/ml and for each study time was: T0=3.25 X 104 (DS+1.9 X 103); T1=2.63X104 (DS+4,50E+03); T2= 1.85 X 104 (DS+9,45E+02); T3=1.93 X103(DS+1,29E+03) y T4=1.2X103 (DS+7,21x102). Conclusion: Within the established time ranges, the tested S.mutans strain remained viable on the plastic surface (AU))


Assuntos
Streptococcus mutans/isolamento & purificação , Transmissão de Doença Infecciosa , Plásticos , Espectrofotometria/métodos , Contagem de Colônia Microbiana/métodos , Descontaminação/métodos , Meios de Cultura , Sobrevivência
3.
Pathogens ; 11(2)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35215168

RESUMO

Sub-Saharan Africa has one of the highest rates of hepatitis B virus (HBV) infection globally, with an incidence of 1.5 million and 0.8 million yearly deaths, which drives synergistic efforts towards its elimination. To assess the risk of mother-to-child transmission of HBV infection, a cross-sectional study was conducted on 1012 pregnant women in Angola to investigate HBV serological and molecular profiles. The prevalence of HBV was 8.7% (n = 88), with hepatitis B core IgM antibody (anti-HBc IgM) positivity identified in 12.8%, hepatitis B "e" antigen (HBeAg) positivity in 30%, and HBV DNA ≥ 200,000 IU/mL in 28.2%. Family tracking studied 44 children, of which 11 (25%) received at least two doses of the hepatitis B vaccine. HBV was detected in 10/44 (22.7%) children, with vaccination reported in one infected child. Further testing identified anti-HBc IgM positivity in 3/10 (30%), HBeAg positivity in 55%, and both seromarkers in 20%. The results revealed the importance of antenatal HBV screening, antiviral prophylaxis for mothers with high viral loads or HBeAg positivity, and timely first-dose hepatitis B vaccines in newborns. Anti-HBc IgM positivity among pregnant women and children highlights prophylactic measures worth considering, including antenatal hepatitis B vaccination and catch-up vaccination to young children.

4.
J Fungi (Basel) ; 7(4)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808442

RESUMO

Clonal outbreaks due to azole-resistant Candida parapsilosis (ARCP) isolates have been reported in numerous studies, but the environmental niche of such isolates has yet to be defined. Herein, we aimed to identify the environmental niche of ARCP isolates causing unremitting clonal outbreaks in an adult ICU from a Brazilian cancer referral center. C. parapsilosis sensu stricto isolates recovered from blood cultures, pericatheter skins, healthcare workers (HCW), and nosocomial surfaces were genotyped by multilocus microsatellite typing (MLMT). Antifungal susceptibility testing was performed by the EUCAST (European Committee for Antimicrobial Susceptibility Testing) broth microdilution reference method and ERG11 was sequenced to determine the azole resistance mechanism. Approximately 68% of isolates were fluconazole-resistant (76/112), including pericatheter skins (3/3, 100%), blood cultures (63/70, 90%), nosocomial surfaces (6/11, 54.5%), and HCW's hands (4/28, 14.2%). MLMT revealed five clusters: the major cluster contained 88.2% of ARCP isolates (67/76) collected from blood (57/70), bed (2/2), pericatheter skin (2/3), from carts (3/7), and HCW's hands (3/27). ARCP isolates were associated with a higher 30 day crude mortality rate (63.8%) than non-ARCP ones (20%, p = 0.008), and resisted two environmental decontamination attempts using quaternary ammonium. This study for the first time identified ARCP isolates harboring the Erg11-Y132F mutation from nosocomial surfaces and HCW's hands, which were genetically identical to ARCP blood isolates. Therefore, it is likely that persisting clonal outbreak due to ARCP isolates was fueled by environmental sources. The resistance of Y132F ARCP isolates to disinfectants, and their potential association with a high mortality rate, warrant vigilant source control using effective environmental decontamination.

5.
Bol Med Hosp Infant Mex ; 78(1): 34-40, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33661873

RESUMO

Background: On March 11, 2020, the World Health Organization declared the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic, and on February 28, Mexico reported its first case. Internationally, cases in newborns are few and the outcomes, in general, are good. There is no certainty of possible vertical transmission, and the presence of the virus in human milk is improbable. The gold standard for diagnosis is the reverse transcription-polymerase chain reaction (RT-PCR) test. We performed a literature review and presented a case of perinatal COVID-19. Clinical case: We describe the case of a full-term male infant with a birth weight of 3450 g and history of rooming-in with another mother-baby pair, both positive for SARS-CoV-2. On the second day of life, the neonate developed pneumonia, with clinical, X-ray and ultrasound diagnostic confirmation. On the third day of life, RT-PCR was positive for SARS-CoV-2; the mother was also positive but remained asymptomatic. The patient required mechanical ventilation and was transferred to a tertiary level neonatal unit on day 5 of life, where congenital heart disease was ruled out. He evolved satisfactorily with a negative RT-PCR test for SARS-CoV-2 on day 8 and was extubated and discharged on day 21 of life. Telephone follow-up was performed without complications. Conclusions: The present case was classified as horizontal transmission with a short incubation period of COVID-19.


Introducción: El 11 de marzo de 2020 la Organización Mundial de la Salud declaró la pandemia por SARS-CoV-2 y el 28 de febrero México reportó su primer caso. En todo el mundo, los casos en recién nacidos son pocos y la evolución, en general, es buena. No hay certeza sobre la posible transmisión vertical, y la presencia del virus en la leche humana es altamente improbable. El método de referencia para el diagnóstico es la prueba de reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR). Se presenta un caso clínico de COVID-19 perinatal y se llevó a cabo una revisión de la literatura sobre el tema. Caso clínico: Recién nacido de sexo masculino, de término, con un peso al nacer de 3,450 g, con antecedente de alojamiento conjunto con otro binomio madre-hijo positivo para SARS-CoV-2. Al segundo día de vida desarrolló neumonía diagnosticada por clínica, rayos X y ultrasonido. Presentó prueba positiva para SARS-CoV-2 al día 3 de vida, al igual que la madre, quien permaneció asintomática. El paciente requirió ventilación mecánica y fue trasladado a una unidad neonatal de tercer nivel el día 5 de vida, donde se descartó cardiopatía congénita y evolucionó satisfactoriamente. La prueba de RT-PCR para SARS-CoV-2 fue negativa al día 8, por lo que se realizó extubación y egreso al día 21 de vida. Se realizó seguimiento telefónico, sin complicaciones. Conclusiones: El presente caso fue catalogado como transmisión horizontal con un periodo corto de incubación de COVID-19.


Assuntos
COVID-19/transmissão , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez/virologia , COVID-19/diagnóstico , Teste para COVID-19 , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , México , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Respiração Artificial , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
6.
Bol. méd. Hosp. Infant. Méx ; 78(1): 34-40, Jan.-Feb. 2021. graf
Artigo em Inglês | LILACS | ID: biblio-1153237

RESUMO

Abstract Background: On March 11, 2020, the World Health Organization declared the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic, and on February 28, Mexico reported its first case. Internationally, cases in newborns are few and the outcomes, in general, are good. There is no certainty of possible vertical transmission, and the presence of the virus in human milk is improbable. The gold standard for diagnosis is the reverse transcription-polymerase chain reaction (RT-PCR) test. We performed a literature review and presented a case of perinatal COVID-19. Clinical case: We describe the case of a full-term male infant with a birth weight of 3450 g and history of rooming-in with another mother-baby pair, both positive for SARS-CoV-2. On the second day of life, the neonate developed pneumonia, with clinical, X-ray and ultrasound diagnostic confirmation. On the third day of life, RT-PCR was positive for SARS-CoV-2; the mother was also positive but remained asymptomatic. The patient required mechanical ventilation and was transferred to a tertiary level neonatal unit on day 5 of life, where congenital heart disease was ruled out. He evolved satisfactorily with a negative RT-PCR test for SARS-CoV-2 on day 8 and was extubated and discharged on day 21 of life. Telephone follow-up was performed without complications. Conclusions: The present case was classified as horizontal transmission with a short incubation period of COVID-19.


Resumen Introducción: El 11 de marzo de 2020 la Organización Mundial de la Salud declaró la pandemia por SARS-CoV-2 y el 28 de febrero México reportó su primer caso. En todo el mundo, los casos en recién nacidos son pocos y la evolución, en general, es buena. No hay certeza sobre la posible transmisión vertical, y la presencia del virus en la leche humana es altamente improbable. El método de referencia para el diagnóstico es la prueba de reacción en cadena de la polimerasa con transcriptasa inversa (RT-PCR). Se presenta un caso clínico de COVID-19 perinatal y se llevó a cabo una revisión de la literatura sobre el tema. Caso clínico: Recién nacido de sexo masculino, de término, con un peso al nacer de 3,450 g, con antecedente de alojamiento conjunto con otro binomio madre-hijo positivo para SARS-CoV-2. Al segundo día de vida desarrolló neumonía diagnosticada por clínica, rayos X y ultrasonido. Presentó prueba positiva para SARS-CoV-2 al día 3 de vida, al igual que la madre, quien permaneció asintomática. El paciente requirió ventilación mecánica y fue trasladado a una unidad neonatal de tercer nivel el día 5 de vida, donde se descartó cardiopatía congénita y evolucionó satisfactoriamente. La prueba de RT-PCR para SARS-CoV-2 fue negativa al día 8, por lo que se realizó extubación y egreso al día 21 de vida. Se realizó seguimiento telefónico, sin complicaciones. Conclusiones: El presente caso fue catalogado como transmisión horizontal con un periodo corto de incubación de COVID-19.


Assuntos
Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Adulto Jovem , Complicações Infecciosas na Gravidez/virologia , Transmissão Vertical de Doenças Infecciosas , COVID-19/transmissão , Complicações Infecciosas na Gravidez/diagnóstico , Respiração Artificial , Seguimentos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Teste para COVID-19 , COVID-19/diagnóstico , México
7.
Mol Genet Genomics ; 295(6): 1339-1353, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32601732

RESUMO

Transposable elements (TEs) are mobile DNA sequences that are able to move from one genomic location to another. These selfish elements are known as genomic parasites, since they hijack the host molecular machinery to generate new copies of themselves. The mobilization of TEs can be seen as a natural mutagen because new TE copies can insert into different loci and impact host genomic structure through different mechanisms. Although our knowledge about TEs is improving with new genomes available, there is still very limited data about the mobilome of species from the Coleoptera order, the most diverse order of insects, including species from the Scarabaeidae family. Therefore, the main goal of this study was to characterize the mobilome of D. (Luederwaldtinia) schiffleri, based on low-coverage genome sequencing, and reconstruct their evolutionary history. We used a combination of four different approaches for TE characterization and maximum likelihood phylogenetic analysis to study their evolution. We found a large and diverse mobilome composed of 38 TE superfamilies, 20 DNA transposon and 18 retrotransposons, accounting for 21% of the genome. Moreover, we found a number of incongruences between the TE and host phylogenetic trees in three DNA transposon TE superfamilies, which represents five TE families, suggesting possible horizontal transfer events between highly divergent taxa. In summary, we found an abundant and diverse mobilome and a number of horizontal transfer events that have shaped the evolutionary history of this species.


Assuntos
Besouros/genética , Elementos de DNA Transponíveis/genética , Evolução Molecular , Transferência Genética Horizontal , Genoma/genética , Filogenia , Animais
8.
J Econ Entomol ; 112(3): 1098-1104, 2019 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-30715431

RESUMO

Horizontal transmission of Helicoverpa armigera nucleopolyhedrovirus (HearNPV) has been found to occur through several pathways involving abiotic factors such as soil, wind, and rain, and biotic factors such as predators, parasitoids, and infected hosts. Previous studies examining horizontal transmission through certain biological carriers speculated they were likely not significant in increasing infection rates, however; these studies only focused on a relatively small number of arthropods present within a field setting. This study was conducted to evaluate the horizontal transmission potential of HearNPV by all potential biological carriers when applied as a foliar bioinsecticide or as virus-infected, nonmotile Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae) larvae in a soybean field. Soybean plots were either sprayed with HearNPV or infested with late-stage HearNPV-infected larvae, and sample zones were sampled 3, 7, 10, 14, 17, and 21 days after the infestation, and analyzed for viral presence using PCR. We then identified HearNPV carriers through contamination from the application (involuntary) or through contact with a HearNPV-infected larva (voluntary). Both were confirmed through PCR analysis. Regardless of application technique, on average, HearNPV was capable of disseminating up to 61.0 m in 3 d after inoculation and was found within the sampled canopy 13-21 d after inoculation. Several arthropods were identified as novel carriers of HearNPV. Results from this study indicate that many novel HearNPV carriers are likely important in disseminating HearNPV.


Assuntos
Mariposas , Nucleopoliedrovírus , Animais , Baculoviridae , Larva
9.
J Infect Dev Ctries ; 13(1): 44-49, 2019 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32032022

RESUMO

INTRODUCTION: Hepatitis B virus (HBV) infection in children is a health problem worldwide. In Mexico, a high prevalence rate of HBV infection and occult HBV infection have been reported in high-risk adults and children. However, studies regarding HBV infection transmitted from HBV-infected parents to children are limited. This study aimed to determine the risk factors associated with HBV transmission of HBV from parents to children in Mexico. METHODOLOGY: A retrospective case-control study was carried out in 24 pediatric patients with clinical HBV infection and 48 healthy controls. Bivariate and forward conditional logistic regression analysis was used to compare demographic variables, the status of HBV vaccination, and risk factors for HBV infection transmission among children and their parents. RESULTS: No newborns were diagnosed with HBV infection, and no significant differences were found in age (p = 0.209) or gender (p = 0.612) compared to the control group. The independent risk factor associated with HBV transmission was the presence of a parent with a history of promiscuity (OR = 30.95, 95%CI = 3.382-283.326; p = 0.002), whereas having completed the HBV vaccination schedule for their age was a protective factor against HBV infection in the children (OR = 0.245, 95%CI = 0.079-0.764; p = 0.015). CONCLUSIONS: HBV infection in Mexican children is associated with close interpersonal contact with a parent engaged in high-risk sexual practices suggesting that the horizontal route could be the primary mode of infection. Child and adult vaccination campaigns should be reinforced to avoid HBV infection in Mexico.


Assuntos
Transmissão de Doença Infecciosa , Saúde da Família , Hepatite B/transmissão , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Hepatite B/epidemiologia , Humanos , Lactente , Recém-Nascido , Masculino , México/epidemiologia , Prevalência , Estudos Retrospectivos , Fatores de Risco , Inquéritos e Questionários
11.
Ciênc. Anim. (Impr.) ; 29(4): 50-57, 2019. tab
Artigo em Português | VETINDEX | ID: biblio-1472527

RESUMO

Protozoários do gênero Neospora adquiriram grande importância ao serem incriminados como causa de aborto em bovinos, ingressando assim, no grupo de patógenos de relevância em medicina veterinária. Atualmente são conhecidas duas espécies potencialmente patogênicas, a saber, N. hughesi e N. caninum. A primeira espécie é relacionada a distúrbios neurológicos em potros e a segunda concorre como possível causa de aborto também em equinos. São conhecidas duas formas de transmissão deste Apicomplexa, a vertical ou transplacentária e a horizontal. Sabidamente fatores referentes ao parasita e ao hospedeiro interferem na eficiência tanto da infecção como na confecção de uma resposta imune efetiva, que culmine com a produção de anticorpos específicos ao imunógeno desafiante. Neste sentido o presente trabalho buscou verificar se as imunoglobulinas produzidas pelo concepto ainda em sua vida intrauterina, mediante desafio endógeno, persistem em seu organismo no seu primeiro ano de vida. Para tal, utilizou-se como forma de diagnóstico a pesquisa de anticorpos via Reação de Imunofluorescência Indireta (RIFI). Foi realizado acompanhamento sorológico de potros congenitamente infectado e livres de Neospora spp. ao nascimento e aos 12 meses de idade. Constatou-se que 40% dos potros congenitamente infectados apresentavam IgG contra Neospora spp. aos 12 meses e, entre os potros soronegativos ao nascimento 28% produziram IgG específico ao final de seu primeiro ano de vida. Estes resultados apontam que a presença de imunoglobulinas específicas antiNeospora spp. ao final do primeiro ano de vida dos potros, independe do status sorológico materno, indicando que a via de infecção horizontal é importante para equinos.


Protozoa of the genus Neospora acquired great importance to be incriminated as a major cause of abortion in cattle in some regions of the planet, thus joining in relevant pathogens group in veterinary medicine. Currently known are two potentially pathogenic species, namely N. hughesi and N. caninum. The first kind is related to neurological disorders in foals and the second competes as a possible cause of abortion also in horses. Two are known forms of transmission of this Apicomplexa, vertical or placenta and the horizontal. Known factors related to the parasite and the host interfere with the efficiency of both the infection and the manufacture of an effective immune response, culminating in the production of specific antibodies to challenging immunogen. In this sense, the present study was to ascertain whether the immunoglobulins produced by the fetus still in its intrauterine life through endogenous challenge, persist in your body in its first year of life. Therefore, we used as a means of diagnosis for antibodies via Immunofluorescence Assay (IFA). Was conducted serological monitoring of congenitally infected foals and free of Neospora spp. birth until they fulfilled: 12 months of age. It was found that 40% of congenitally infected foals had IgG against Neospora spp. at 12 months, and among seronegative foals at birth 28% produced specific IgG to the end of their first year of life. These results indicate that thepresence of specific anti-Neospora spp. immunoglobulins. the end of the first year of foals, independent of maternal HIV status, indicating that the horizontal infection pathway is important for horses.


Assuntos
Animais , Cavalos/parasitologia , Coccidiose/congênito , Coccidiose/diagnóstico , Coccidiose/transmissão , Coccidiose/veterinária , Neospora , Técnica Indireta de Fluorescência para Anticorpo/veterinária
12.
Ciênc. Anim. (Impr.) ; 29(4): 50-57, 2019. tab
Artigo em Português | VETINDEX | ID: vti-25357

RESUMO

Protozoários do gênero Neospora adquiriram grande importância ao serem incriminados como causa de aborto em bovinos, ingressando assim, no grupo de patógenos de relevância em medicina veterinária. Atualmente são conhecidas duas espécies potencialmente patogênicas, a saber, N. hughesi e N. caninum. A primeira espécie é relacionada a distúrbios neurológicos em potros e a segunda concorre como possível causa de aborto também em equinos. São conhecidas duas formas de transmissão deste Apicomplexa, a vertical ou transplacentária e a horizontal. Sabidamente fatores referentes ao parasita e ao hospedeiro interferem na eficiência tanto da infecção como na confecção de uma resposta imune efetiva, que culmine com a produção de anticorpos específicos ao imunógeno desafiante. Neste sentido o presente trabalho buscou verificar se as imunoglobulinas produzidas pelo concepto ainda em sua vida intrauterina, mediante desafio endógeno, persistem em seu organismo no seu primeiro ano de vida. Para tal, utilizou-se como forma de diagnóstico a pesquisa de anticorpos via Reação de Imunofluorescência Indireta (RIFI). Foi realizado acompanhamento sorológico de potros congenitamente infectado e livres de Neospora spp. ao nascimento e aos 12 meses de idade. Constatou-se que 40% dos potros congenitamente infectados apresentavam IgG contra Neospora spp. aos 12 meses e, entre os potros soronegativos ao nascimento 28% produziram IgG específico ao final de seu primeiro ano de vida. Estes resultados apontam que a presença de imunoglobulinas específicas antiNeospora spp. ao final do primeiro ano de vida dos potros, independe do status sorológico materno, indicando que a via de infecção horizontal é importante para equinos.(AU)


Protozoa of the genus Neospora acquired great importance to be incriminated as a major cause of abortion in cattle in some regions of the planet, thus joining in relevant pathogens group in veterinary medicine. Currently known are two potentially pathogenic species, namely N. hughesi and N. caninum. The first kind is related to neurological disorders in foals and the second competes as a possible cause of abortion also in horses. Two are known forms of transmission of this Apicomplexa, vertical or placenta and the horizontal. Known factors related to the parasite and the host interfere with the efficiency of both the infection and the manufacture of an effective immune response, culminating in the production of specific antibodies to challenging immunogen. In this sense, the present study was to ascertain whether the immunoglobulins produced by the fetus still in its intrauterine life through endogenous challenge, persist in your body in its first year of life. Therefore, we used as a means of diagnosis for antibodies via Immunofluorescence Assay (IFA). Was conducted serological monitoring of congenitally infected foals and free of Neospora spp. birth until they fulfilled: 12 months of age. It was found that 40% of congenitally infected foals had IgG against Neospora spp. at 12 months, and among seronegative foals at birth 28% produced specific IgG to the end of their first year of life. These results indicate that thepresence of specific anti-Neospora spp. immunoglobulins. the end of the first year of foals, independent of maternal HIV status, indicating that the horizontal infection pathway is important for horses.(AU)


Assuntos
Animais , Cavalos/parasitologia , Neospora , Coccidiose/congênito , Coccidiose/veterinária , Coccidiose/diagnóstico , Coccidiose/transmissão , Técnica Indireta de Fluorescência para Anticorpo/veterinária
13.
Ticks Tick Borne Dis ; 9(5): 1133-1136, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29703549

RESUMO

Rickettsia parkeri strain Atlantic rainforest (SAR) is the etiological agent of a spotted fever group rickettsiosis in Brazil, where it is transmitted to humans by the tick Amblyomma ovale. A previous study demonstrated that R. parkeri SAR was successfully maintained in A. ovale ticks by transstadial and transovarial passages; however, because this agent induced lower reproduction rates in A. ovale, the participation of a vertebrate amplifier host, yet to be determined, was speculated. Since the rice rat Euryoryzomys russatus was demonstrated to be the most important host for immature stages of A. ovale in a focus of R. parkeri SAR transmission, the present study evaluated the competence of rice rats to act as amplifying host of R. parkeri SAR for A. ovale ticks. Rice rats were infested with R. parkeri SAR-infected A. ovale nymphs, and four days later with uninfected A. ovale larvae. Rickettsial transmission to rats was confirmed by seroconversion to R. parkeri antigens. Detached engorged larvae were allowed to molt to nymphs, in which rickettsial DNA was detected in up to 60% (mean: 20%) of the specimens. When part of these nymphs was allowed to feed on susceptible rice rats, rickettsial transmission was confirmed by seroconversion, indicating that there was successful horizontal transmission of R. parkeri SAR from infected nymphs to uninfected larvae in the previous acquisition infestations. Because we used naïve, susceptible rats, we infer that this horizontal transmission occurred via a systemic infection (rickettsemia) in the rat. Our results, coupled with previous epidemiological studies, suggest that under natural conditions rice rats could be acting as amplifying hosts of R. parkeri SAR to A. ovale ticks.


Assuntos
Ixodidae/microbiologia , Infecções por Rickettsia/sangue , Infecções por Rickettsia/epidemiologia , Rickettsia/isolamento & purificação , Sigmodontinae/microbiologia , Sigmodontinae/parasitologia , Infestações por Carrapato/epidemiologia , Animais , Anticorpos Antibacterianos/sangue , Brasil/epidemiologia , DNA Bacteriano/genética , Transmissão de Doença Infecciosa , Larva/microbiologia , Ninfa/microbiologia , Ratos/parasitologia , Rickettsia/genética , Rickettsia/imunologia , Infecções por Rickettsia/imunologia , Infecções por Rickettsia/transmissão , Infestações por Carrapato/parasitologia
14.
R Soc Open Sci ; 4(5): 161013, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28572992

RESUMO

The attine ant system is a remarkable example of symbiosis. An antagonistic partner within this system is the fungal parasite Escovopsis, a genus specific to the fungal gardens of the Attini. Escovopsis parasitizes the Leucoagaricus symbiont that leaf-cutting ants (Acromyrmex, Atta) have been farming over the past 8-12 Myr. However, it has been a puzzle how Escovopsis reaches its host. During a seasonal survey of nests of Acromyrmex subterraneus subterraneus in Atlantic rainforest in Brazil, Escovopsis was detected in all the sampled fungal garden waste tips or middens (n = 111). Middens were built strategically; always below the nest entrances. Here, we report the first evidence of a putative mechanism for horizontal transmission of Escovopsis between attine colonies. It is posited that leaf-cutting ants pick up the spores from soil and litter during foraging and vector the mycoparasite between attine colonies. Field and laboratory experiments, using At. laevigata and Ac. subterraneus subterraneus, confirm that Escovopsis spores are phoretic, and have an inbuilt dormancy, broken by the presence of their Leucoagaricus host. However, in the coevolutionary arms race, Atta ants may lose out-despite most species in the genus investing in a more advanced waste disposal system-due to the insanitary habits of their Acromyrmex neighbours.

15.
Rev. chil. infectol ; Rev. chil. infectol;33(6): 703-705, dic. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1042631

RESUMO

We report a Serratia marcescens outbreak occurred in the NICU of a pediatric hospital in Guayaquil, Ecuador. Nine cases of infection were detected, from which septicemia was developed in 55.5%. The index case was a newborn derived from another institution with septic arthritis caused by the outbreak strain. The infection rate was 17.6% and mortality rate was 33.3%. All isolates were resistant to aminoglycosides and susceptible to third generation cephalosporins and carbapenems. Clonality analysis by pulsed-field gel electrophoresis (PFGE) revealed the presence of two closely related clones confirming the horizontal spread. Measures were taken by the committee such as: strengthening the hand hygiene, patient hygiene and cohort studies of gastrointestinal colonization, which allowed the control of the outbreak.


Comunicamos un brote nosocomial por Serratia marcescens en una Unidad de Cuidados Intensivos en un hospital pediátrico de Guayaquil, Ecuador. Se detectaron nueve casos de infección, manifestándose en 55,5% de los casos como sepsis. El caso índice correspondió a un neonato derivado de otra institución con artritis séptica. La tasa de ataque fue 17,6% (n: 51) y la mortalidad 33,3%. Todos los aislados presentaron resistencia a las cefalosporinas y aminoglucósidos y sensibilidad a carbapenémicos. El análisis de clonalidad reveló la presencia de dos clones estrechamente relacionados, confirmando la diseminación horizontal. Las medidas de control de brote fueron: reforzamiento de higiene de manos, cohorte de los pacientes y búsqueda de colonización gastrointestinal.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Serratia marcescens/isolamento & purificação , Unidades de Terapia Intensiva Neonatal , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Infecções por Serratia/epidemiologia , Serratia marcescens/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Infecção Hospitalar/microbiologia , Infecções por Serratia/microbiologia , Equador/epidemiologia
16.
FEMS Microbiol Ecol ; 91(4)2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25764472

RESUMO

Despite Wolbachia being widespread among terrestrial isopods, studies on this symbiotic relationship are still incipient in the Neotropical region. The aims of the present study were to investigate the presence and prevalence of Wolbachia in natural populations of terrestrial isopod species in South America, and to analyze the diversity and phylogenetic relationships of Wolbachia strains. A total of 1172 individuals representing 11 families and 35 species were analyzed. We observed distinct evolutionary scenarios according to the geographical origins of the species: strains harbored by most of the introduced species belong to the Oniclade in supergroup B and are identical to those found in their original ecozone (i.e. Palearctic). On the other hand, the strains found in native Neotropical terrestrial isopods showed low prevalence, high diversity and none of them belonged to the Oniclade, although most belonged to supergroup B. The dynamics of infection in Neotropical species seems to be the result of several events of loss and acquisition of the bacteria, which refutes the hypothesis of an ancestral acquisition of Wolbachia in Oniscidea. The presence of strains from supergroups A and F was also detected for the first time in terrestrial isopods, revealing a Wolbachia diversity previously unknown for this group of host.


Assuntos
Isópodes/microbiologia , Wolbachia/classificação , Wolbachia/genética , Animais , Técnicas de Tipagem Bacteriana , Sequência de Bases , Biodiversidade , Evolução Biológica , DNA Bacteriano/genética , Variação Genética/genética , Geografia , Tipagem de Sequências Multilocus , Filogenia , Análise de Sequência de DNA , América do Sul , Simbiose
17.
Proc Biol Sci ; 281(1785): 20140474, 2014 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-24807259

RESUMO

In horizontally transmitted mutualisms, mutualists disperse separately and reassemble in each generation with partners genetically unrelated to those in the previous generation. Because of this, there should be no selection on either partner to enhance the other's reproductive output directly. In symbiotic ant-plant mutualisms, myrmecophytic plants host defensive ant colonies, and ants defend the plants from herbivores. Plants and ants disperse separately, and, although ant defence can indirectly increase plant reproduction by reducing folivory, it is unclear whether ants can also directly increase plant reproduction by defending seeds. The neotropical tree Cordia alliodora hosts colonies of Azteca pittieri ants. The trees produce domatia where ants nest at stem nodes and also at the node between the peduncle and the rachides of the infloresence. Unlike the stem domatia, these reproductive domatia senesce after the tree fruits each year. In this study, I show that the tree's resident ant colony moves into these ephemeral reproductive domatia, where they tend honeydew-producing scale insects and patrol the nearby developing fruits. The presence of ants significantly reduced pre-dispersal seed predation by Amblycerus bruchid beetles, thereby directly increasing plant reproductive output.


Assuntos
Formigas/fisiologia , Besouros/fisiologia , Cordia/crescimento & desenvolvimento , Simbiose , Animais , Herbivoria , México , Caules de Planta/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento
18.
Vet Parasitol ; 202(3-4): 257-64, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24560936

RESUMO

The aim of this study was to determine the transmission paths of Neospora caninum in a dairy herd of crossbred cattle. Two hundred and ninety animals were grouped according to the year of their birth to verify the distribution of infection according to age. The blood of 196 cattle was collected thrice, with an average interval of 210 days, to evaluate the existence of horizontal transmission in the herd. To evaluate vertical transmission, the blood of 64 calves was collected prior to ingestion of colostrum and from their mothers at parturition. Moreover, 63 family trees were built. The presence of anti-N. caninum antibodies was detected using an indirect fluorescent antibody test. The chi-square test (χ(2)) with Yates' correction or Fisher's exact test was used to evaluate the relation between the serology and age groups and between the serostatus of cows and their progeny in different calvings. A higher seropositivity (p=0.035) was found in animals born in 2008 compared to those born in 1997-2007. The serological status of only 13 animals presented changes, of which six (3.1%) became seropositive, indicating a low proportion of horizontal transmission. All seropositive cows gave birth to seropositive calves, resulting in 100% vertical transmission. Sixty-three family trees were constructed. In 29 (46%) of these families, there were animals seropositive for N. caninum. Congenital infection in relation to the number of births was estimated from the relation of Mother+ and Daughter+, without significant differences (p=0.84) between the number of births and the transmission of the parasite from infected cows to their progeny. The low proportion of horizontal transmission combined with the high proportion of vertical transmission allowed us to conclude that transplacental transmission is the principal route of N. caninum infection in the herd.


Assuntos
Doenças dos Bovinos/transmissão , Coccidiose/veterinária , Transmissão Vertical de Doenças Infecciosas/veterinária , Neospora/fisiologia , Animais , Anticorpos Antiprotozoários/sangue , Brasil , Bovinos , Coccidiose/transmissão , Cães , Feminino , Masculino , Gravidez
19.
Rev. Soc. Bras. Med. Trop ; Rev. Soc. Bras. Med. Trop;45(3): 301-304, May-June 2012. tab
Artigo em Inglês | LILACS | ID: lil-640424

RESUMO

INTRODUCTION:The objectives of this study were evaluate hepatitis B virus (HBV) serological markers in children and adolescents followed up at the Child Institute of the Hospital das Clínicas, Faculdade de Medicina de São Paulo, Universidade de São Paulo; identify chronic HBV carriers and susceptible individuals in the intrafamilial environment; characterize HBV genotypes; and identify mutations in the patients and household contacts. METHODS: Ninety-five hepatitis B surface antigen-positive children aged <19 years and 118 household contacts were enrolled in this study. Commercial kits were used for the detection of serological markers, and PCR was used for genotyping. RESULTS: Hepatitis B e antigen (HBeAg) was detected in 66.3% (63/95) of cases. Three of the 30 HBeAg-negative and anti-HBeAg-positive patients presented with precore mutations and 11 presented with mutations in the basal core promoter (BCP). Genotype A was identified in 39 (43.8%) patients, genotype D in 45 (50.6%), and genotype C in 5 (5.6%). Of the 118 relatives, 40 were chronic HBV carriers, 52 presented with the anti-HBc marker, 19 were vaccinated, and 7 were susceptible. Among the relatives, genotypes A, D, and C were the most frequent. One parent presented with a precore mutation and 4 presented with BCP mutations. CONCLUSIONS: Genotypes A and D were the most frequent among children, adolescents, and their relatives. The high prevalence of HBV in the families showed the possibility of its intrafamilial transmission.


INTRODUÇÃO: Os objetivos deste estudo foram: avaliar os marcadores sorológicos nas crianças e adolescentes acompanhadas no Instituto da Criança do Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP); identificar portadores crônicos do VHB e indivíduos suscetíveis no ambiente intrafamiliar; caracterizar o genótipo do VHB; observar a presença de cepas mutantes entre os pacientes e familiares estudados. MÉTODOS: Noventa e cinco crianças e adolescentes positivas para o antígeno de superfície do vírus da Hepatite B (AgHBs), menores de 19 anos, e 118 familiares foram envolvidos neste estudo. Foram utilizados kits comerciais para a pesquisa dos marcadores sorológicos e a PCR foi utilizada para genotipagem. RESULTADOS: O antígeno e do vírus da hepatite B (AgHBe) foi detectado em 66,3% (63/95) dos casos. Três dos 30 pacientes AgHBe negativo e anti-HBe positivo apresentaram mutação na região pré-core e 11 na região BCP. Em 39 (43,8%) pacientes, foi identificado o genótipo A, 45 (50,6%)o genótipo D e cinco (5,6%) o genótipo C. Dos 118 familiares estudados, 40 eram portadores crônicos do VHB, 52 tinham marcador sorológico de contato prévio e sete eram suscetíveis. Dentre os familiares AgHBs positivos, os genótipos A, D e C foram os mais frequentes. Um familiar apresentou mutação na região pré-core e quatro apresentaram mutação na região do BCP. CONCLUSÕES: Os genótipos A e D foram os mais frequentes dentre as crianças adolescentes e seus familiares. Alta frequência do VHB nos familiares mostrou a possibilidade de transmissão intrafamiliar.


Assuntos
Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Adulto Jovem , Família , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Mutação/genética , Portador Sadio , Busca de Comunicante , DNA Viral/genética , Ensaio de Imunoadsorção Enzimática , Genótipo , Anticorpos Anti-Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/transmissão , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas
20.
Ciênc. rural ; Ciênc. rural (Online);41(11): 1867-1870, nov. 2011. tab
Artigo em Português | LILACS | ID: lil-608043

RESUMO

A transmissão horizontal de fungos entomopatogênicos tem papel importante na epizootiologia, pois está diretamente associada à disseminação do agente causal da doença de insetos. Em hospedeiros que apresentam restrita mobilidade, a presença de pragas secundárias no agroecossistema pode ajudar na formação de focos secundários da doença e, com isso, aumentar a mortalidade das pragas-chave. Para tanto, a disseminação de Beauveria bassiana, introduzida inoculativamente através de iscas tipo telha, foi avaliada em um bananal infestado por Cosmopolites sordidus (Piracicaba) e outro por C. sordidus e Metamasius hemipterus (Botucatu). Constatou-se que, em Piracicaba, não foram capturados insetos infectados na testemunha, sendo os índices de infecção nas parcelas que receberam B. bassiana de 8 e 15 por cento. Em Botucatu, o índice de infecção dos insetos capturados na testemunha chegou a 17 por cento, enquanto que, nas parcelas tratadas, variou de 28 a 54 por cento. Os resultados obtidos neste trabalho demostram que a presença de M. hemipterus influenciou na disseminação de B. bassiana para a população de C. sordidus, praga-chave dessa cultura.


Horizontal transmission of entomopathogenic fungi plays an important role in the epizootiology, because it is directly associated with the spread of causal agents of insect diseases. In hosts with restricted mobility, the presence of secondary pests in the agroecosystem can help in the formation of secondary disease outbreaks and increase the mortality of the target pest. For this purpose, the dissemination of Beauveria bassiana inoculated using tile-type baits was evaluated in a banana plantation infested with Cosmopolites sordidus (Piracicaba) and one with C. sordidus and Metamasius hemipterus (Botucatu). In Piracicaba, insects contaminated with the pathogen were not found in the control group, and infection rates in the plots that received B. bassiana ranged between 8 and 15 percent. In Botucatu, the infection rate of insects in the control reached 17 percent, whereas in the fungal treatment plots, it varied from 28 to 54 percent. The present results demonstrate the influence of M. hemipterus in the dissemination of B. bassiana in populations of C. sordidus, a target pest of this crop.

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