Érica Teixeira - Academia.edu (original) (raw)
Papers by Érica Teixeira
<b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazil... more <b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazilian Propolis"Evidence-based Complementary and Alternative Medicine 2005;2(1):33-38.Published online 09 Feb 2005PMCID:PMC1062153.© The Author (2005). Published by Oxford University Press. All rights reserved. Propolis was removed from the left side and bees are working to seal the resultant opening with new propolis deposits.
Brazil, though the Africanized honeybees are considered resistant and tolerant to most of bee pat... more Brazil, though the Africanized honeybees are considered resistant and tolerant to most of bee pathogens and parasites, in recent years considerable losses have been reported in some localities, especially in the Southeast and Southern states. Since the phenomenon that is affecting honeybees around the world has been observed also in Brazil (with less intensity), we proposed a research project aiming to determine possible causes for such decline or losses, and in particular to test the likelihoods of specific predicted causative agent(s) for this condition. Alternative approaches, including genetic screening can be extremely useful and can accelerate important discoveries related to the current problem. Here it was present an overview about these activitites and a summary (2009 to 2011) of the situation in the two regions. No symptoms of the American Foul Brood were detected and analysis of more than 600 honey samples presented negative results, using the Brazilian official method fo...
Journal of Apicultural Research, 2012
Honey bee losses in Brazil have been observed over the past few years. These losses share somewha... more Honey bee losses in Brazil have been observed over the past few years. These losses share somewhat similar symptoms with the syndrome known as Colony Collapse Disorder (CCD) in the USA. After more than a half century of introgression from Apis mellifera subsp. scutellata, Africanized honey bees have tolerance against Varroa destructor and other parasites and other pathogens (Aumeier et al., 2001; Guzman-Novoa et al., 1999; Mondragon et al., 2005; Moretto and Mello, 1999; 2001; Rosenkranz, 1999; Vandame et al., 2002). Consequently, it was surprising when serious population declines were observed in southern Brazil. Specifically, decreased bee populations and significant colony losses have been observed in Sao Paulo state, generally between March and July (autumn and winter in the Southern Hemisphere). We are actively testing these bees for indicators or causes of these losses, and for any similarities between colony losses in Brazil and CCD as described in the USA (vanEngelsdorp et al., 2009). This disorder, whereby the majority of worker bees in a colony disappear over a matter of weeks, often leaving healthy brood behind, has been tied to losses of 30-90% of colonies from some beekeeping operations in the USA (vanEngelsdorp and Meixner, 2010). Cox-Foster et al. (2007) used a metagenomic approach to survey microbes in CCD hives, normal hives, and imported royal jelly. Candidate pathogens were screened for significance of association with CCD, and IAPV, a positive stranded RNA virus belonging to the genus Aparavirus, family Dicistroviridae, displayed a strong correlation with CCD in surveyed colonies.
Molecular Ecology Resources, 2008
Aethina tumida, a beetle parasite of honey bee colonies, has recently and dramatically expanded i... more Aethina tumida, a beetle parasite of honey bee colonies, has recently and dramatically expanded its range and now parasitizes honey bees on three continents. Polymorphic microsatellite loci for this beetle species will help map this continuing range expansion, and will also prove useful for exploring the mating system and local gene flow patterns for this important parasite. We describe 15 loci that are polymorphic in both the native and introduced ranges of this species, showing from two to 22 alleles.
Journal of Invertebrate Pathology, 2008
This work describes the first molecular-genetic evidence for viruses in Brazilian honey bee sampl... more This work describes the first molecular-genetic evidence for viruses in Brazilian honey bee samples. Three different bee viruses, Acute bee paralysis virus (ABPV), Black queen cell virus (BQCV), and Deformed wing virus (DWV) were identified during a screening of RNAs from 1920 individual adult bees collected in a region of southeastern Brazil that has recently shown unusual bee declines. ABPV was detected in 27.1% of colony samples, while BQCV and DWV were found in 37% and 20.3%, respectively. These levels are substantially lower than the frequencies found for these viruses in surveys from other parts of the world. We also developed and validated a multiplex RT-PCR assay for the simultaneous detection of ABPV, BQCV, and DWV in Brazil.
Journal of Invertebrate Pathology, 2013
Until the mid-1990s, the only microsporidium known to infect bees of the genus Apis was Nosema ap... more Until the mid-1990s, the only microsporidium known to infect bees of the genus Apis was Nosema apis. A second species, Nosema ceranae, was first identified in 1996 from Asian honey bees; it is postulated that this parasite was transmitted from the Asian honey bee, Apis cerana, to the European honey bee, Apis mellifera. Currently, N. ceranae is found on all continents and has often been associated with honey bee colony collapse and other reports of high bee losses. Samples of Africanized drones collected in 1979, preserved in alcohol, were analyzed by light microscopy to count spores and were subjected to DNA extraction, after which duplex PCR was conducted. All molecular analyses (triplicate) indicated that the drones were infected with both N. ceranae and N. apis. PCR products were sequenced and matched to sequences reported in the GenBank (Acc. Nos. JQ639316.1 and JQ639301.1). The venation pattern of the wings of these males was compared to those of the current population living in the same area and with the pattern of drones collected in 1968 from Ribeirão Preto, SP, Brazil, from a location close to where African swarms first escaped in 1956. The morphometric results indicated that the population collected in 1979 was significantly different from the current living population, confirming its antiquity. Considering that the use of molecular tools for identifying Nosema species is relatively recent, it is possible that previous reports of infections (which used only light microscopy, without ultrastructural analysis) wrongly identified N. ceranae as N. apis. Although we can conclude that N. ceranae has been affecting Africanized honeybees in Brazil for at least 34 years, the impact of this pathogen remains unclear.
Apidologie, 2016
Honeybees are essential components to modern agriculture and economy. However, a continuous incre... more Honeybees are essential components to modern agriculture and economy. However, a continuous increase in cases of colony losses and colony depopulation are being reported worldwide. This critical situation has put the fragile equilibrium between bees and plants on the edge. As a consequence, several scientists have begun to focus their lines of research on this issue. Most researchers agree that there is no single explanation for the observed colony losses. Instead, these losses result from a synergistic interaction between different stressors. South America is not the exception; several cases of colony losses and colony depopulation were reported by beekeepers throughout the continent, yet no accurate data has been published to date. Therefore, this article attempts to analyze the past and present situation of honeybee health in South America, specifically in Argentina, Chile, Uruguay, Brazil, and Venezuela. Furthermore, it is intended to serve as a comparison to future colony losses, as well as to provide guidance for future hypothesis-driven research on the causes of colony mortality. We evaluate the impact of the main parasites and pathogens affecting honeybee colonies and discuss the role of each with respect to reported honeybee losses. We also contemplate the main challenges that each nation must confront with regards to honeybee health.
There is an increasing need for substances with antiviral activity since the treatment of viral i... more There is an increasing need for substances with antiviral activity since the treatment of viral infections with most antivirals is often unsatisfactory due to the problem of, amongst other things, viral latency and the likelihood of new viral agents arising. Previously we isolated bauer-7-en-3-yl acetate (BA), a pentacyclic triterpenoid obtained from the chloroform extract of an sample of propolis from southeast Brazil (TEIXEIRA, et al., 2006). Here we investigated the antiviral activity of BA against the alphaherpesviruses bovine herpesvirus 1 (BoHV-1) and pseudorabiesvirus (SuHV-1, suid herpesvirus) during infection of Madin-Darby bovine kidney (MDBK) and African green monkey kidney (VERO) cells cultures, respectively. In short, BA was tested for its cytotoxic properties and antiviral effect through virus yield reduction and virucidal activity in both cells. Results showed that BA 20µg mL-1 and 15µg mL-1 were the maximal non-cytotoxic concentration (MNCC) to VERO and MDBK cells, respectively. BA reduced significantly SuHV-1 titrers in both antiviral tests (p<0.05) while inhibition was not observed against BoHV-1. However, how BA interferes on the virus multiplication still need to be elucidated.
<b>Copyright information:</b>Taken from "Plant Origin of Green Propolis: Bee Beh... more <b>Copyright information:</b>Taken from "Plant Origin of Green Propolis: Bee Behavior, Plant Anatomy and Chemistry"Evidence-based Complementary and Alternative Medicine 2005;2(1):85-92.Published online 06 Jan 2005PMCID:PMC1062148.© The Author (2005). Published by Oxford University Press. All rights reserved. St, starch inclusion.
<b>Copyright information:</b>Taken from "Plant Origin of Green Propolis: Bee Beh... more <b>Copyright information:</b>Taken from "Plant Origin of Green Propolis: Bee Behavior, Plant Anatomy and Chemistry"Evidence-based Complementary and Alternative Medicine 2005;2(1):85-92.Published online 06 Jan 2005PMCID:PMC1062148.© The Author (2005). Published by Oxford University Press. All rights reserved. Du, resiniferous duct; Ep, epiderm; GT, glandular trichome; P, phloem; X, xylem.
<b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazil... more <b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazilian Propolis"Evidence-based Complementary and Alternative Medicine 2005;2(1):33-38.Published online 09 Feb 2005PMCID:PMC1062153.© The Author (2005). Published by Oxford University Press. All rights reserved. () 2,2-Dimethyl-8-prenylchromene; () 4-hydroxy-3,5-diprenyl cinnamic acid (artepillin C); () 3-prenyl cinnamic acid allyl ester; () kaempferide; () propolis benzofuran A. See text for references.
<b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazil... more <b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazilian Propolis"Evidence-based Complementary and Alternative Medicine 2005;2(1):33-38.Published online 09 Feb 2005PMCID:PMC1062153.© The Author (2005). Published by Oxford University Press. All rights reserved. () Isocupressic acid, a labdane diterpenoid; (B) 13C-symphyoreticulic acid, a clerodane diterpenoid; (C) esters of long chain fatty acids (3-hydroxystearic acid = 11, procrim a; 3-hydroxystearic acid = 13, procrim b) and a pentacyclic triterpenoid (lupeol); (D) Farnesol a sesquiterpenoid, see text for references.
Previous studies suggested that the Brazilian sac brood disease (BSB) may be caused by some conte... more Previous studies suggested that the Brazilian sac brood disease (BSB) may be caused by some content present in the ethanol soluble extract from pollen grains of Stryphnodendron polyphyllum, plant species containing high level of tannin. Bioassays showed that larvae of honeybee Apis mellifera present signals of BSB disease when fed on diet containing tannic acid. This study investigated the effect of diet containing tannic acid on the midgut epithelium of A. mellifera larvae. Bee larvae were fed at field and laboratory conditions with artificial food. Results did not show any morphological changes in the midgut of larvae fed on diet containing tannic acid.
Alternative approaches including metagenomic and genetic screening can be extremely useful and ca... more Alternative approaches including metagenomic and genetic screening can be extremely useful and can accelerate important discoveries related to a current phenomenon wich affect honey bees around the world (characterized by the depopulation or sudden losses of hives). To determine possible causes for the decline in honey bee colonies from southeastern Brazil, and in particular to test the likelihoods of specific predicted causative agent(s) for this condition, a diverse set of analyses were proposed. These analyses form part of a more extensive Epidemiological Evaluation Program for bees in southeastern Brazil. Here we present an overview about part of this Program. Three viruses were identified (Acute Bee Paralysis Virus-ABPV, Black Queen Cell Virus-BQCV, and Deformed Wing Virus-DWV) in 1,920 analyzed bees, and a multiplex RT-PCR assay was developed and validated. Although strategy adopted to analyze data in details is still being evaluated and prepared by the authors, the first results indicated that ca. 26 % of the samples carried Israeli Acute Paralysis Virus (IAPV), and some isolates for this virus were found. Nosema ceranae, Melissococus pluton, Leptomonas apis, and Spiroplasma apis were also detected. Pathological, epidemiological, and widespread studies remain to be conducted once no single pathogen seems overly predominant in declining bee colonies.
MicrobiologyOpen, 2014
Two species of Spiroplasma (Mollicutes) bacteria were isolated from and described as pathogens of... more Two species of Spiroplasma (Mollicutes) bacteria were isolated from and described as pathogens of the European honey bee, Apis mellifera, ~30 years ago but recent information on them is lacking despite global concern to understand bee population declines. Here we provide a comprehensive survey for the prevalence of these two Spiroplasma species in current populations of honey bees using improved molecular diagnostic techniques to assay multiyear colony samples from North America (U.S.A.) and South America (Brazil). Significant annual and seasonal fluctuations of Spiroplasma apis and Spiroplasma melliferum prevalence in colonies from the U.S.A. (n = 616) and Brazil (n = 139) occurred during surveys from 2011 through 2013. Overall, 33% of U.S.A. colonies and 54% of Brazil colonies were infected by Spiroplasma spp., where S. melliferum predominated over S. apis in both countries (25% vs. 14% and 44% vs. 38% frequency, respectively). Colonies were co-infected by both species more freque...
iz.sp.gov.br
There is an increasing need for substances with antiviral activity since the treatment of viral i... more There is an increasing need for substances with antiviral activity since the treatment of viral infections with most antivirals is often unsatisfactory due to the problem of, amongst other things, viral latency and the likelihood of new viral agents arising. Previously we isolated bauer-7-en-3-yl acetate (BA), a pentacyclic triterpenoid obtained from the chloroform extract of an sample of propolis from southeast Brazil (TEIXEIRA, et al., 2006). Here we investigated the antiviral activity of BA against the alphaherpesviruses bovine herpesvirus 1 (BoHV-1) and pseudorabiesvirus (SuHV-1, suid herpesvirus) during infection of Madin-Darby bovine kidney (MDBK) and African green monkey kidney (VERO) cells cultures, respectively. In short, BA was tested for its cytotoxic properties and antiviral effect through virus yield reduction and virucidal activity in both cells. Results showed that BA 20µg mL-1 and 15µg mL-1 were the maximal non-cytotoxic concentration (MNCC) to VERO and MDBK cells, respectively. BA reduced significantly SuHV-1 titrers in both antiviral tests (p<0.05) while inhibition was not observed against BoHV-1. However, how BA interferes on the virus multiplication still need to be elucidated.
<b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazil... more <b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazilian Propolis"Evidence-based Complementary and Alternative Medicine 2005;2(1):33-38.Published online 09 Feb 2005PMCID:PMC1062153.© The Author (2005). Published by Oxford University Press. All rights reserved. Propolis was removed from the left side and bees are working to seal the resultant opening with new propolis deposits.
Brazil, though the Africanized honeybees are considered resistant and tolerant to most of bee pat... more Brazil, though the Africanized honeybees are considered resistant and tolerant to most of bee pathogens and parasites, in recent years considerable losses have been reported in some localities, especially in the Southeast and Southern states. Since the phenomenon that is affecting honeybees around the world has been observed also in Brazil (with less intensity), we proposed a research project aiming to determine possible causes for such decline or losses, and in particular to test the likelihoods of specific predicted causative agent(s) for this condition. Alternative approaches, including genetic screening can be extremely useful and can accelerate important discoveries related to the current problem. Here it was present an overview about these activitites and a summary (2009 to 2011) of the situation in the two regions. No symptoms of the American Foul Brood were detected and analysis of more than 600 honey samples presented negative results, using the Brazilian official method fo...
Journal of Apicultural Research, 2012
Honey bee losses in Brazil have been observed over the past few years. These losses share somewha... more Honey bee losses in Brazil have been observed over the past few years. These losses share somewhat similar symptoms with the syndrome known as Colony Collapse Disorder (CCD) in the USA. After more than a half century of introgression from Apis mellifera subsp. scutellata, Africanized honey bees have tolerance against Varroa destructor and other parasites and other pathogens (Aumeier et al., 2001; Guzman-Novoa et al., 1999; Mondragon et al., 2005; Moretto and Mello, 1999; 2001; Rosenkranz, 1999; Vandame et al., 2002). Consequently, it was surprising when serious population declines were observed in southern Brazil. Specifically, decreased bee populations and significant colony losses have been observed in Sao Paulo state, generally between March and July (autumn and winter in the Southern Hemisphere). We are actively testing these bees for indicators or causes of these losses, and for any similarities between colony losses in Brazil and CCD as described in the USA (vanEngelsdorp et al., 2009). This disorder, whereby the majority of worker bees in a colony disappear over a matter of weeks, often leaving healthy brood behind, has been tied to losses of 30-90% of colonies from some beekeeping operations in the USA (vanEngelsdorp and Meixner, 2010). Cox-Foster et al. (2007) used a metagenomic approach to survey microbes in CCD hives, normal hives, and imported royal jelly. Candidate pathogens were screened for significance of association with CCD, and IAPV, a positive stranded RNA virus belonging to the genus Aparavirus, family Dicistroviridae, displayed a strong correlation with CCD in surveyed colonies.
Molecular Ecology Resources, 2008
Aethina tumida, a beetle parasite of honey bee colonies, has recently and dramatically expanded i... more Aethina tumida, a beetle parasite of honey bee colonies, has recently and dramatically expanded its range and now parasitizes honey bees on three continents. Polymorphic microsatellite loci for this beetle species will help map this continuing range expansion, and will also prove useful for exploring the mating system and local gene flow patterns for this important parasite. We describe 15 loci that are polymorphic in both the native and introduced ranges of this species, showing from two to 22 alleles.
Journal of Invertebrate Pathology, 2008
This work describes the first molecular-genetic evidence for viruses in Brazilian honey bee sampl... more This work describes the first molecular-genetic evidence for viruses in Brazilian honey bee samples. Three different bee viruses, Acute bee paralysis virus (ABPV), Black queen cell virus (BQCV), and Deformed wing virus (DWV) were identified during a screening of RNAs from 1920 individual adult bees collected in a region of southeastern Brazil that has recently shown unusual bee declines. ABPV was detected in 27.1% of colony samples, while BQCV and DWV were found in 37% and 20.3%, respectively. These levels are substantially lower than the frequencies found for these viruses in surveys from other parts of the world. We also developed and validated a multiplex RT-PCR assay for the simultaneous detection of ABPV, BQCV, and DWV in Brazil.
Journal of Invertebrate Pathology, 2013
Until the mid-1990s, the only microsporidium known to infect bees of the genus Apis was Nosema ap... more Until the mid-1990s, the only microsporidium known to infect bees of the genus Apis was Nosema apis. A second species, Nosema ceranae, was first identified in 1996 from Asian honey bees; it is postulated that this parasite was transmitted from the Asian honey bee, Apis cerana, to the European honey bee, Apis mellifera. Currently, N. ceranae is found on all continents and has often been associated with honey bee colony collapse and other reports of high bee losses. Samples of Africanized drones collected in 1979, preserved in alcohol, were analyzed by light microscopy to count spores and were subjected to DNA extraction, after which duplex PCR was conducted. All molecular analyses (triplicate) indicated that the drones were infected with both N. ceranae and N. apis. PCR products were sequenced and matched to sequences reported in the GenBank (Acc. Nos. JQ639316.1 and JQ639301.1). The venation pattern of the wings of these males was compared to those of the current population living in the same area and with the pattern of drones collected in 1968 from Ribeirão Preto, SP, Brazil, from a location close to where African swarms first escaped in 1956. The morphometric results indicated that the population collected in 1979 was significantly different from the current living population, confirming its antiquity. Considering that the use of molecular tools for identifying Nosema species is relatively recent, it is possible that previous reports of infections (which used only light microscopy, without ultrastructural analysis) wrongly identified N. ceranae as N. apis. Although we can conclude that N. ceranae has been affecting Africanized honeybees in Brazil for at least 34 years, the impact of this pathogen remains unclear.
Apidologie, 2016
Honeybees are essential components to modern agriculture and economy. However, a continuous incre... more Honeybees are essential components to modern agriculture and economy. However, a continuous increase in cases of colony losses and colony depopulation are being reported worldwide. This critical situation has put the fragile equilibrium between bees and plants on the edge. As a consequence, several scientists have begun to focus their lines of research on this issue. Most researchers agree that there is no single explanation for the observed colony losses. Instead, these losses result from a synergistic interaction between different stressors. South America is not the exception; several cases of colony losses and colony depopulation were reported by beekeepers throughout the continent, yet no accurate data has been published to date. Therefore, this article attempts to analyze the past and present situation of honeybee health in South America, specifically in Argentina, Chile, Uruguay, Brazil, and Venezuela. Furthermore, it is intended to serve as a comparison to future colony losses, as well as to provide guidance for future hypothesis-driven research on the causes of colony mortality. We evaluate the impact of the main parasites and pathogens affecting honeybee colonies and discuss the role of each with respect to reported honeybee losses. We also contemplate the main challenges that each nation must confront with regards to honeybee health.
There is an increasing need for substances with antiviral activity since the treatment of viral i... more There is an increasing need for substances with antiviral activity since the treatment of viral infections with most antivirals is often unsatisfactory due to the problem of, amongst other things, viral latency and the likelihood of new viral agents arising. Previously we isolated bauer-7-en-3-yl acetate (BA), a pentacyclic triterpenoid obtained from the chloroform extract of an sample of propolis from southeast Brazil (TEIXEIRA, et al., 2006). Here we investigated the antiviral activity of BA against the alphaherpesviruses bovine herpesvirus 1 (BoHV-1) and pseudorabiesvirus (SuHV-1, suid herpesvirus) during infection of Madin-Darby bovine kidney (MDBK) and African green monkey kidney (VERO) cells cultures, respectively. In short, BA was tested for its cytotoxic properties and antiviral effect through virus yield reduction and virucidal activity in both cells. Results showed that BA 20µg mL-1 and 15µg mL-1 were the maximal non-cytotoxic concentration (MNCC) to VERO and MDBK cells, respectively. BA reduced significantly SuHV-1 titrers in both antiviral tests (p<0.05) while inhibition was not observed against BoHV-1. However, how BA interferes on the virus multiplication still need to be elucidated.
<b>Copyright information:</b>Taken from "Plant Origin of Green Propolis: Bee Beh... more <b>Copyright information:</b>Taken from "Plant Origin of Green Propolis: Bee Behavior, Plant Anatomy and Chemistry"Evidence-based Complementary and Alternative Medicine 2005;2(1):85-92.Published online 06 Jan 2005PMCID:PMC1062148.© The Author (2005). Published by Oxford University Press. All rights reserved. St, starch inclusion.
<b>Copyright information:</b>Taken from "Plant Origin of Green Propolis: Bee Beh... more <b>Copyright information:</b>Taken from "Plant Origin of Green Propolis: Bee Behavior, Plant Anatomy and Chemistry"Evidence-based Complementary and Alternative Medicine 2005;2(1):85-92.Published online 06 Jan 2005PMCID:PMC1062148.© The Author (2005). Published by Oxford University Press. All rights reserved. Du, resiniferous duct; Ep, epiderm; GT, glandular trichome; P, phloem; X, xylem.
<b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazil... more <b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazilian Propolis"Evidence-based Complementary and Alternative Medicine 2005;2(1):33-38.Published online 09 Feb 2005PMCID:PMC1062153.© The Author (2005). Published by Oxford University Press. All rights reserved. () 2,2-Dimethyl-8-prenylchromene; () 4-hydroxy-3,5-diprenyl cinnamic acid (artepillin C); () 3-prenyl cinnamic acid allyl ester; () kaempferide; () propolis benzofuran A. See text for references.
<b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazil... more <b>Copyright information:</b>Taken from "Origin and Chemical Variation of Brazilian Propolis"Evidence-based Complementary and Alternative Medicine 2005;2(1):33-38.Published online 09 Feb 2005PMCID:PMC1062153.© The Author (2005). Published by Oxford University Press. All rights reserved. () Isocupressic acid, a labdane diterpenoid; (B) 13C-symphyoreticulic acid, a clerodane diterpenoid; (C) esters of long chain fatty acids (3-hydroxystearic acid = 11, procrim a; 3-hydroxystearic acid = 13, procrim b) and a pentacyclic triterpenoid (lupeol); (D) Farnesol a sesquiterpenoid, see text for references.
Previous studies suggested that the Brazilian sac brood disease (BSB) may be caused by some conte... more Previous studies suggested that the Brazilian sac brood disease (BSB) may be caused by some content present in the ethanol soluble extract from pollen grains of Stryphnodendron polyphyllum, plant species containing high level of tannin. Bioassays showed that larvae of honeybee Apis mellifera present signals of BSB disease when fed on diet containing tannic acid. This study investigated the effect of diet containing tannic acid on the midgut epithelium of A. mellifera larvae. Bee larvae were fed at field and laboratory conditions with artificial food. Results did not show any morphological changes in the midgut of larvae fed on diet containing tannic acid.
Alternative approaches including metagenomic and genetic screening can be extremely useful and ca... more Alternative approaches including metagenomic and genetic screening can be extremely useful and can accelerate important discoveries related to a current phenomenon wich affect honey bees around the world (characterized by the depopulation or sudden losses of hives). To determine possible causes for the decline in honey bee colonies from southeastern Brazil, and in particular to test the likelihoods of specific predicted causative agent(s) for this condition, a diverse set of analyses were proposed. These analyses form part of a more extensive Epidemiological Evaluation Program for bees in southeastern Brazil. Here we present an overview about part of this Program. Three viruses were identified (Acute Bee Paralysis Virus-ABPV, Black Queen Cell Virus-BQCV, and Deformed Wing Virus-DWV) in 1,920 analyzed bees, and a multiplex RT-PCR assay was developed and validated. Although strategy adopted to analyze data in details is still being evaluated and prepared by the authors, the first results indicated that ca. 26 % of the samples carried Israeli Acute Paralysis Virus (IAPV), and some isolates for this virus were found. Nosema ceranae, Melissococus pluton, Leptomonas apis, and Spiroplasma apis were also detected. Pathological, epidemiological, and widespread studies remain to be conducted once no single pathogen seems overly predominant in declining bee colonies.
MicrobiologyOpen, 2014
Two species of Spiroplasma (Mollicutes) bacteria were isolated from and described as pathogens of... more Two species of Spiroplasma (Mollicutes) bacteria were isolated from and described as pathogens of the European honey bee, Apis mellifera, ~30 years ago but recent information on them is lacking despite global concern to understand bee population declines. Here we provide a comprehensive survey for the prevalence of these two Spiroplasma species in current populations of honey bees using improved molecular diagnostic techniques to assay multiyear colony samples from North America (U.S.A.) and South America (Brazil). Significant annual and seasonal fluctuations of Spiroplasma apis and Spiroplasma melliferum prevalence in colonies from the U.S.A. (n = 616) and Brazil (n = 139) occurred during surveys from 2011 through 2013. Overall, 33% of U.S.A. colonies and 54% of Brazil colonies were infected by Spiroplasma spp., where S. melliferum predominated over S. apis in both countries (25% vs. 14% and 44% vs. 38% frequency, respectively). Colonies were co-infected by both species more freque...
iz.sp.gov.br
There is an increasing need for substances with antiviral activity since the treatment of viral i... more There is an increasing need for substances with antiviral activity since the treatment of viral infections with most antivirals is often unsatisfactory due to the problem of, amongst other things, viral latency and the likelihood of new viral agents arising. Previously we isolated bauer-7-en-3-yl acetate (BA), a pentacyclic triterpenoid obtained from the chloroform extract of an sample of propolis from southeast Brazil (TEIXEIRA, et al., 2006). Here we investigated the antiviral activity of BA against the alphaherpesviruses bovine herpesvirus 1 (BoHV-1) and pseudorabiesvirus (SuHV-1, suid herpesvirus) during infection of Madin-Darby bovine kidney (MDBK) and African green monkey kidney (VERO) cells cultures, respectively. In short, BA was tested for its cytotoxic properties and antiviral effect through virus yield reduction and virucidal activity in both cells. Results showed that BA 20µg mL-1 and 15µg mL-1 were the maximal non-cytotoxic concentration (MNCC) to VERO and MDBK cells, respectively. BA reduced significantly SuHV-1 titrers in both antiviral tests (p<0.05) while inhibition was not observed against BoHV-1. However, how BA interferes on the virus multiplication still need to be elucidated.