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1.
Neotrop Entomol ; 50(2): 312-316, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32845459

RESUMEN

Aethina tumida Murray is currently a worldwide emergent pest of Apis mellifera L. hives. Although the damaging effect on the colony stores and brood is well known, the possible role of these beetles as a disease carrier is not clear. This is the first report of DNA presence of the trypanosome honeybee parasite Lotmaria passim and Crithidia bombi, and the Apis mellifera filamentous virus (AmFV) in A. tumida. Further studies will be needed to determine if A. tumida is indeed a mechanical or biological vector of these pathogens.


Asunto(s)
Abejas , Escarabajos , Trypanosoma/aislamiento & purificación , Animales , Escarabajos/parasitología
2.
Bull Entomol Res ; 111(1): 100-110, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32594919

RESUMEN

Apis mellifera is infected by more than 24 virus species worldwide, mainly positive-sense, single-stranded RNA viruses of the Dicistroviridae and Iflaviridae families. Among the viruses that infect honey bees, Deformed wing virus is the most prevalent and is present as three master variants DWV-A, B, and C. Given that the ectoparasitic mite Varroa destructor vectors these virus variants, recombination events between them are expected, and variants and their recombinants can co-exist in mites and honeybees at the same time. In this study, we detect, through RT-qPCR, the presence of DWV-A and B in the same samples of adult bees from colonies of Argentina. Total RNA was extracted from pools of ten adult bees from 45 apiaries distributed across the main beekeeping Provinces of Argentina (Buenos Aires, Santa Fe, Córdoba, Santiago del Estero, Río Negro, and Mendoza); then RT-qPCR reactions were performed to detect DWV-A and B, with specific primer pairs. After the amplifications, PCR products (204 and 660 bp amplicons for DWV-B, and ~250 bp for DWV-A) were purified and sequenced to verify that they corresponded to reported sequences, analyzing them using the Blast software. Of the 45 samples analyzed by RT-qPCR, over 90% were infected with DWV-A and 47% were also positive for DWV-B, where it was found in high prevalence specifically in colonies of A. mellifera of the Buenos Aires Province. Future studies will determine the impact of this type of the virus and its ability to recombine with the other DWV types in the apiaries of our country.


Asunto(s)
Abejas/virología , Virus ARN/aislamiento & purificación , Animales , Argentina , Virus ARN/clasificación , Virus ARN/genética , ARN Viral/análisis , Reacción en Cadena en Tiempo Real de la Polimerasa
3.
Arch Soc Esp Oftalmol (Engl Ed) ; 95(6): 279-283, 2020 Jun.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32376128

RESUMEN

CLINICAL CASE: Forteen year old patient presenting progressive decrease in visual acuity of the left eye after 3 months of evolution. On examination he presents bilateral drusen of papilla, associated with juxtapapillary neovascular membrane, which seriously compromises the vision and visual field of the left eye. RESULT: Treatment with 3 consecutive injections of intravitreal ranibizumab resulted in the inactivation of the neovascular membrane with reabsorption of subretinal fluid and improvement of the best corrected visual acuity of the left eye. After 9 months of follow-up, it was 20/20 and stable. CONCLUSION: Although optic nerve head drusen are considered benign, neovascular membranes can be a complication. Anti-VEGFs are an effective alternative for treatment.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Neovascularización Coroidal/tratamiento farmacológico , Drusas del Disco Óptico/tratamiento farmacológico , Ranibizumab/uso terapéutico , Adolescente , Neovascularización Coroidal/complicaciones , Femenino , Humanos , Drusas del Disco Óptico/etiología
4.
Sci Total Environ ; 713: 136554, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-31955084

RESUMEN

This work reports the spatial and temporal variations on the dynamics of OCPs, PCBs, PBDEs and chlorpyrifos in honey bee, bee bread and honey samples, as well as soil and flowers from the surrounding areas, considering, different land uses. Honey bee samples showed the highest pollutant levels, with a predominance of the industrial contaminants over pesticides. Chlorpyrifos showed the highest concentration during the application period in almost all samples from the soybean field (S2), in concordance with its current use. By other hand, the recalcitrant compounds such as, DDTs, BDE #47 and also light PCBs exhibited the highest levels in beehive samples from the field adjacent to urban disposal waste (S3). In both soils and flower samples a prevalence of obsolete compounds over chlorpyrifos was observed, and the 6-CB predominated among the homologous groups of PCBs These results highlights the importance of soils as sink of these persistent contaminants, which became available depending on environmental conditions. Results revealed that the land uses and seasonal variations have directly impacted on the levels of agrochemicals, PCBs and PBDEs found in the beehive matrixes. This survey provides novel evidence about the current situation of pollution on honey bee colonies under temperate climates and contributes to the knowledge of this poor studied topic in Argentina.


Asunto(s)
Miel , Animales , Argentina , Abejas , Cloropirifos , Contaminantes Ambientales
5.
Exp Appl Acarol ; 56(4): 309-18, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22349941

RESUMEN

Although mitochondrial DNA mapping of Varroa destructor revealed the presence of several haplotypes, only two of them (Korean and Japanese haplotypes) were capable to infest Apis mellifera populations. Even though the Korean haplotype is the only one that has been reported in Argentina, these conclusions were based on mites sampled in apiaries from a specific geographical place (Buenos Aires province). To study mites from several sites of Argentina could reveal the presence of the Japanese genotype, especially considering sites near to Brazil, where Japanese haplotype was already detected. The aim of this work was to study the genetic structure of V. destructor populations from apiaries located in various provinces of Argentina, in order to determine the presence of different haplotypes. The study was carried out between January 2006 and December 2009. Phoretic adult Varroa mites were collected from honey bee workers sampled from colonies of A. mellifera located in Entre Ríos, Buenos Aires, Corrientes, Río Negro, Santa Cruz and Neuquén provinces. Twenty female mites from each sampling site were used to carry out the genetic analysis. For DNA extraction a nondestructive method was used. DNA sequences were compared to Korean haplotype (AF106899) and Japanese haplotype (AF106897). All DNA sequences obtained from mite populations sampled in Argentina, share 98% of similitude with Korean Haplotype (AF106899). Taking into account these results, we are able to conclude that Korean haplotype is cosmopolite in Argentina.


Asunto(s)
Abejas/parasitología , Varroidae/genética , Animales , Secuencia de Bases , ADN Mitocondrial/química , ADN Mitocondrial/genética , Complejo IV de Transporte de Electrones/química , Complejo IV de Transporte de Electrones/genética , Femenino , Variación Genética , Haplotipos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Alineación de Secuencia , Análisis de Secuencia de ADN , Varroidae/enzimología
6.
Nat Prod Res ; 25(4): 397-406, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20623426

RESUMEN

In this study, chemical composition, physicochemical properties and bioactivity of two essential oils of Rosmarinus officinalis extracted from plant material with different drying treatments against Apis mellifera, Varroa destructor and Paenibacillus larvae were assessed. The lethal concentration 50 (LC50) for mites and bees was estimated using a complete exposure method test. The broth microdilution method was followed in order to determine the minimum inhibitory concentrations (MICs) of the essential oils against P. larvae. Physicochemical properties were similar in both the essential oils, but the percentage of components showed certain differences according to their drying treatment. ß-Myrcene and 1,8-cineole were the main constituents in the oils. The LC50 for complete exposure method at 24, 48 and 72 h was minor for mites exposed to R. officinalis essential oil dried in oven conditions. MIC values were 700-800 µg mL(-1) and 1200 µg mL(-1) for R. officinalis dried in air and oven conditions, respectively. The results reported in this research show that oil toxicity against V. destructor and P. larvae differed depending on the drying treatment of the plant material before the distillation of essential oil.


Asunto(s)
Abejas/efectos de los fármacos , Aceites Volátiles/química , Aceites Volátiles/farmacología , Paenibacillus/efectos de los fármacos , Rosmarinus/química , Varroidae/efectos de los fármacos , Animales , Antiinfecciosos/química , Antiinfecciosos/farmacología , Insecticidas/química , Insecticidas/farmacología
7.
Rev. méd. Chile ; 134(11): 1417-1426, nov. 2006. tab
Artículo en Español | LILACS | ID: lil-439937

RESUMEN

Backgrounds: There is a high prevalence of obesity and hyperinsulinism among Chilean prepuberal children. Aim: To evaluate insulin sensitivity (IS) using fasting insulin, the Homeostasis Model Assessment (HOMA) and quantitative insulin-sensitivity check index (QUICKI) in Chilean children. Material and Methods: Body mass index (BMI), total body fat percentage ( percentTBF) using the sum of 4 skin folds, abdominal obesity determined through waist circumference (WC), pubertal maturation using five Tanner stages, fasting glucose (Glu) and insulin (Ins), were measured in 354 children aged 6 to 15 years (173 males). IS was evaluated using HOMA and QUICKI. Results: IS was strongly associated with percentTBF and WC. Ins, HOMA and QUICKI were significantly correlated with BMI (r =0.412; 0.405 y -0.442, respectively), percentTBF (r =0.370; 0.367 y -0.394, respectively), and WC (r =0.452; 0.446 y -0.481, respectively). Ins and HOMA increased and QUICKI decreased significantly (p <0.0001) with age. Children in a similar Tanner stage did not have differences in Ins, HOMA and QUICKI. No differences in Ins, HOMA and QUICKI were observed between children in Tanner stages 1 and 2. However, children in Tanner stages 1 and 2, had significantly lower Ins and HOMA and higher QUICKI than those in Tanner 3 to 5 stages. The highest Ins quartile for Tanner stages 1 and 2 was 10.0 æUI/dl; for Tanner stages 3 to five, the figure was 15.6 æUI/dl. Conclusions: These results confirm the relationship of IS with BMI, percentTBF, WC and pubertal maturation. IS decreases significantly and fasting Ins levels increase approximately 50 percent with puberty. This fact must be considered for the diagnosis of hyperinsulinism and insulin resistance in children.


Asunto(s)
Adolescente , Niño , Femenino , Humanos , Masculino , Glucemia/análisis , Resistencia a la Insulina , Insulina/sangre , Estado Nutricional , Obesidad/sangre , Pubertad/sangre , Índice de Masa Corporal , Prueba de Tolerancia a la Glucosa , Homeostasis , Valores de Referencia , Factores de Riesgo
8.
Rev Med Chil ; 134(11): 1417-26, 2006 Nov.
Artículo en Español | MEDLINE | ID: mdl-17277855

RESUMEN

BACKGROUND: There is a high prevalence of obesity and hyperinsulinism among Chilean prepuberal children. AIM: To evaluate insulin sensitivity (IS) using fasting insulin, the Homeostasis Model Assessment (HOMA) and quantitative insulin-sensitivity check index (QUICKI) in Chilean children. MATERIAL AND METHODS: Body mass index (BMI), total body fat percentage (%TBF) using the sum of 4 skin folds, abdominal obesity determined through waist circumference (WC), pubertal maturation using five Tanner stages, fasting glucose (Glu) and insulin (Ins), were measured in 354 children aged 6 to 15 years (173 males). IS was evaluated using HOMA and QUICKI. RESULTS: IS was strongly associated with %TBF and WC. Ins, HOMA and QUICKI were significantly correlated with BMI (r =0.412; 0.405 y -0.442, respectively), %TBF (r =0.370; 0.367 y -0.394, respectively), and WC (r =0.452; 0.446 y -0.481, respectively). Ins and HOMA increased and QUICKI decreased significantly (p <0.0001) with age. Children in a similar Tanner stage did not have differences in Ins, HOMA and QUICKI. No differences in Ins, HOMA and QUICKI were observed between children in Tanner stages 1 and 2. However, children in Tanner stages 1 and 2, had significantly lower Ins and HOMA and higher QUICKI than those in Tanner 3 to 5 stages. The highest Ins quartile for Tanner stages 1 and 2 was 10.0 micro UI/dl; for Tanner stages 3 to five, the figure was 15.6 microUI/dl. CONCLUSIONS: These results confirm the relationship of IS with BMI, %TBF, WC and pubertal maturation. IS decreases significantly and fasting Ins levels increase approximately 50% with puberty. This fact must be considered for the diagnosis of hyperinsulinism and insulin resistance in children.


Asunto(s)
Glucemia/análisis , Resistencia a la Insulina , Insulina/sangre , Estado Nutricional , Obesidad/sangre , Pubertad/sangre , Adolescente , Índice de Masa Corporal , Niño , Femenino , Prueba de Tolerancia a la Glucosa , Homeostasis , Humanos , Masculino , Valores de Referencia , Factores de Riesgo
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