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1.
J Psychiatr Res ; 173: 151-156, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38531145

RESUMEN

Treatment response is hard to predict and detailed mechanisms unknown. Lower levels of the dehydroepiandrosterone sulphate (DHEA(S)) - a precursor to testosterone and estrogen - have been associated to depression and to response to antidepressant treatment. Previous studies however may have been ridden by confounding and reverse causation. The aim of this study is to evaluate whether higher levels of DHEA(S) are causally linked to response to antidepressants using mendelian randomization (MR). We performed a Two-sample MR analysis using data the largest publicly available GWAS of DHEA(S) levels (n = 14,846) using eight common genetic variants associated to DHEA(S) (seven single nucleotide polymorphisms and one variant rs2497306) and the largest GWAS of antidepressant response (n = 5218) using various MR methods (IVW, MR Egger, Weighted mean, weighted mode, MR-PRESSO) and single SNP analysis. We further investigated for pleiotropy conducting a look up on PhenoScanner and GWAS Catalog. Results show no evidence for DHEA(S) gene risk score from any of MR methods, however, we found a significant association on individual variant analysis for rs11761538, rs17277546, and rs2497306. There was some evidence for heterogeneity and pleiotropy. This is the first paper to show some evidence for a causal association of genetically-predicted DHEA and improvement of depressive symptoms. The effect is not a simple linear effect, and we were unable to dissect whether the effect was direct effect of DHEA(S), mediated by DHEA(S) or on the pathway is not yet clear. Further studies using more refined instrumental variables will help clarify this association.


Asunto(s)
Antidepresivos , Análisis de la Aleatorización Mendeliana , Humanos , Antidepresivos/farmacología , Antidepresivos/uso terapéutico , Puntuación de Riesgo Genético , Polimorfismo de Nucleótido Simple/genética , Deshidroepiandrosterona , Estudio de Asociación del Genoma Completo
2.
J Photochem Photobiol B ; 227: 112379, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34998114

RESUMEN

In this work the thermal diffusivity (D) of Astyanax lacustris fish scale is investigated aiming to use it for environmental integrity certification. The D values were obtained by a relatively simple procedure by a photoacoustic method. The chosen fish species is from wide occurrence in Brasil's basins. It has short migration, and it has also been used as environmental bioindicator. The results obtained in 195 scales sampled from three different streams in the Midwest region in Brazil gives an average value of D ~ 4 × 10-3 cm2/s. ANCOVA analysis demonstrated that D values are able to differentiate among the three basins and indicates that it is dependent on the scales thickness and water conductivity. This last one is strongly affected by biotic and abiotic actions, so that D values measured by photoacoustic method can be used for interpreting the environmental integrity from where the fishes were sampled.


Asunto(s)
Monitoreo del Ambiente , Peces , Animales , Brasil , Ecosistema , Monitoreo del Ambiente/métodos , Análisis Espectral
3.
Psychiatry Res ; 282: 112607, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31630039

RESUMEN

Rapidly urbanizing areas of Latin America experience elevated but unevenly distributed levels of violence. Extensive research suggests that individual exposure to violence is associated with higher odds of both internalizing (anxiety and mood) and externalizing (substance and intermittent explosive) mental disorders. Less research, however, has focused on how neighborhood-level violence, as an indicator of broader neighborhood contexts, might relate to the mental health of residents, independently of an individual's personal exposure. We used multilevel analyses to examine associations of neighborhood-level violence with individual-level past-year mental disorders, controlling for individual-level violence exposure. We used data from 7,251 adults nested in 83 neighborhoods within five large Latin American cities as part of the WHO World Mental Health Surveys. Accounting for individual-level violence exposure, living in neighborhoods with more violence was associated with significantly elevated odds of individual-level internalizing disorders, but not externalizing disorders. Caution should be exercised when making causal inferences regarding the effects of neighborhood-level violence in the absence of experimental interventions. Nevertheless, neighborhood context, including violence, should be considered in the study of mental disorders. These findings are particularly relevant for rapidly urbanizing areas with high levels of violence, such as Latin America.


Asunto(s)
Trastornos Mentales/epidemiología , Violencia/psicología , Adolescente , Adulto , Ciudades , Femenino , Encuestas Epidemiológicas , Humanos , América Latina/epidemiología , Masculino , Trastornos Mentales/psicología , Salud Mental , Análisis Multinivel , Características de la Residencia , Urbanización , Adulto Joven
4.
Neotrop Entomol ; 48(6): 1030-1038, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31456168

RESUMEN

Chemical compounds present on the cuticle of social insects are important in communication, as they are used in recognition of nestmates and sexual partners as well as in caste distinction, varying according to several factors, such as genetic and environmental. In this context, some studies have explored the cuticular chemical profile as a tool for assessing intra- and interspecific differences in social insects, although few studies have investigated this in social wasps. This study aimed to assess the differences in cuticular chemical profiles among different geographic samples of the wasp Mischocyttarus consimilis Zikán. Our hypothesis was that environmental factors are decisive to compose the cuticular chemical profiles of colonies of these social wasps and that there are differences regarding the geographic distribution among colonies. We used Fourier Transform Infrared-Photoacoustic Spectroscopy (FTIR-PAS) to assess the chemical profiles of samples. Our results show that despite there are differences between the cuticular chemical composition of the wasps' samples from different populations, there is no significant correlation compared to the spatial distribution of the colonies nor with the environment. Thus, our hypothesis was refuted, and we can infer that in this species neither exogenous nor genetic factors stand out to differentiate the chemical signature of their colonies, but a combination of both.


Asunto(s)
Estructuras Animales/química , Variación Biológica Poblacional , Espectroscopía Infrarroja por Transformada de Fourier , Avispas/química , Animales , Brasil , Geografía
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 217: 190-196, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30939365

RESUMEN

The thermoxidation of biodiesel was monitored using different spectroscopic techniques: UV-Vis and MIR absorption, Raman spectroscopy, and visible fluorescence. As the oxidation progressed, the UV-Vis absorption spectra showed an increase in the spectral range between 34,000 and 26,000 cm-1, while two main fluorescence bands (under ultraviolet excitation) were observed at around 21,000 and 15,000 cm-1. The UV-Vis absorption and fluorescence intensities presented opposite behavior during the processes, irrespective of the temperature used (90, 140, or 190 °C). These effects could be explained by the consumption of natural antioxidants, followed by the formation of primary oxidation compounds. The Raman and MIR absorption results indicated the existence of a cis-trans isomerization effect, followed by the formation of hydroperoxides during the oxidation, with the behavior being the same as that revealed by the UV-Vis absorption and fluorescence analyses. The comparison, under the same conditions, of different spectroscopy techniques that can be used to monitor the stages of thermoxidation of soybean biofuel provides important information for selection of an appropriate technique for evaluating biodiesel integrity.


Asunto(s)
Biocombustibles/análisis , Glycine max/química , Calor , Espectrometría de Fluorescencia/métodos , Espectrofotometría Ultravioleta/métodos , Espectrometría Raman/métodos , Oxidación-Reducción
6.
Appl Opt ; 57(16): 4672-4676, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29877376

RESUMEN

During beer production, the mashing process is fundamental for extraction of the main sugars from the starch. The quantification of these fermentable sugars during the process provides a measure of the alcoholic content of the final beer. Therefore, monitoring of the sugar composition during beer production is very important for obtaining a quality product. This paper demonstrates the potential of white light interferometry (WLI) for monitoring the extraction of sugars in different mashing processes, by observing the refractive index of the mixture. All the mashings presented linear increases of the refractive index during the temperature steps, which were influenced by the concentrations of sugars produced in each step. Cauchy parameters obtained by refractive index interpretation showed the influence of carbohydrates on absorption in the infrared region, and amino acids on absorption in the ultraviolet region. Strong correlation was obtained between the refractive index and °Bx values, indicating that the WLI technique is a potential analytical method for monitoring the mashing process during beer production.

7.
Epidemiol Psychiatr Sci ; 27(6): 552-567, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29283080

RESUMEN

AIMS: A substantial proportion of persons with mental disorders seek treatment from complementary and alternative medicine (CAM) professionals. However, data on how CAM contacts vary across countries, mental disorders and their severity, and health care settings is largely lacking. The aim was therefore to investigate the prevalence of contacts with CAM providers in a large cross-national sample of persons with 12-month mental disorders. METHODS: In the World Mental Health Surveys, the Composite International Diagnostic Interview was administered to determine the presence of past 12 month mental disorders in 138 801 participants aged 18-100 derived from representative general population samples. Participants were recruited between 2001 and 2012. Rates of self-reported CAM contacts for each of the 28 surveys across 25 countries and 12 mental disorder groups were calculated for all persons with past 12-month mental disorders. Mental disorders were grouped into mood disorders, anxiety disorders or behavioural disorders, and further divided by severity levels. Satisfaction with conventional care was also compared with CAM contact satisfaction. RESULTS: An estimated 3.6% (standard error 0.2%) of persons with a past 12-month mental disorder reported a CAM contact, which was two times higher in high-income countries (4.6%; standard error 0.3%) than in low- and middle-income countries (2.3%; standard error 0.2%). CAM contacts were largely comparable for different disorder types, but particularly high in persons receiving conventional care (8.6-17.8%). CAM contacts increased with increasing mental disorder severity. Among persons receiving specialist mental health care, CAM contacts were reported by 14.0% for severe mood disorders, 16.2% for severe anxiety disorders and 22.5% for severe behavioural disorders. Satisfaction with care was comparable with respect to CAM contacts (78.3%) and conventional care (75.6%) in persons that received both. CONCLUSIONS: CAM contacts are common in persons with severe mental disorders, in high-income countries, and in persons receiving conventional care. Our findings support the notion of CAM as largely complementary but are in contrast to suggestions that this concerns person with only mild, transient complaints. There was no indication that persons were less satisfied by CAM visits than by receiving conventional care. We encourage health care professionals in conventional settings to openly discuss the care patients are receiving, whether conventional or not, and their reasons for doing so.


Asunto(s)
Trastornos de Ansiedad/terapia , Terapias Complementarias , Trastornos Mentales/terapia , Trastornos del Humor/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Trastornos de Ansiedad/epidemiología , Femenino , Encuestas Epidemiológicas , Humanos , Trastornos Mentales/epidemiología , Persona de Mediana Edad , Trastornos del Humor/epidemiología , Satisfacción Personal , Índice de Severidad de la Enfermedad , Adulto Joven
8.
Artículo en Inglés | MEDLINE | ID: mdl-28689076

RESUMEN

Thermal lens spectroscopy (TLS) in the near-near-infrared region was used to explore the absorptions of overtones and combination bands of sulfentrazone (SFZ) herbicide diluted in methanol. This spectroscopic region was chosen in order to guarantee that only thermal lens effect is noted during the experimental procedure. The results showed that it was possible to detect very low concentrations (~2ng/µL) of SFZ in methanol by determining its thermal diffusivity or the absorption coefficient due to the 3ν(NH)+1δ(CH) combination band. This minimum SFZ concentration is the limit observed by chromatography method. The findings demonstrated that the TLS can be used for precise and accurate assessment of pesticides in ecosystems. Besides, the 3ν(NH)+1δ(CH) combination band at 960nm can be used as a marker for SFZ in methanol.

10.
Acta Psychiatr Scand ; 136(1): 74-84, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28542726

RESUMEN

OBJECTIVE: While psychotic experiences (PEs) are known to be associated with a range of mental and general medical disorders, little is known about the association between PEs and measures of disability. We aimed to investigate this question using the World Mental Health surveys. METHOD: Lifetime occurrences of six types of PEs were assessed along with 21 mental disorders and 14 general medical conditions. Disability was assessed with a modified version of the WHO Disability Assessment Schedule. Descriptive statistics and logistic regression models were used to investigate the association between PEs and high disability scores (top quartile) with various adjustments. RESULTS: Respondents with PEs were more likely to have top quartile scores on global disability than respondents without PEs (19.1% vs. 7.5%; χ2  = 190.1, P < 0.001) as well as greater likelihood of cognitive, social, and role impairment. Relationships persisted in each adjusted model. A significant dose-response relationship was also found for the PE type measures with most of these outcomes. CONCLUSIONS: Psychotic experiences are associated with disability measures with a dose-response relationship. These results are consistent with the view that PEs are associated with disability regardless of the presence of comorbid mental or general medical disorders.


Asunto(s)
Personas con Discapacidad/estadística & datos numéricos , Salud Global/estadística & datos numéricos , Salud Mental/estadística & datos numéricos , Trastornos Psicóticos/epidemiología , Adulto , Encuestas Epidemiológicas/estadística & datos numéricos , Humanos , Organización Mundial de la Salud
11.
Neotrop Entomol ; 46(6): 642-648, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28255952

RESUMEN

In the present work, we explored multiple data from different biological levels such as cuticular hydrocarbons, chromosomal features, and mtDNA sequences in the Neotropical social wasp Mischocyttarus consimilis (J.F. Zikán). Particularly, we explored the genetic and chemical differentiation level within and between populations of this insect. Our dataset revealed shallow intraspecific differentiation in M. consimilis. The similarity among the analyzed samples can probably be due to the geographical proximity where the colonies were sampled, and we argue that Paraná River did not contribute effectively as a historical barrier to this wasp.


Asunto(s)
Cromosomas de Insectos , ADN Mitocondrial/genética , Hidrocarburos/análisis , Avispas/genética , Avispas/metabolismo , Estructuras Animales/metabolismo , Animales , Avispas/química
12.
Psychol Med ; 47(10): 1744-1760, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28222820

RESUMEN

BACKGROUND: Although specific phobia is highly prevalent, associated with impairment, and an important risk factor for the development of other mental disorders, cross-national epidemiological data are scarce, especially from low- and middle-income countries. This paper presents epidemiological data from 22 low-, lower-middle-, upper-middle- and high-income countries. METHOD: Data came from 25 representative population-based surveys conducted in 22 countries (2001-2011) as part of the World Health Organization World Mental Health Surveys initiative (n = 124 902). The presence of specific phobia as defined by the Diagnostic and Statistical Manual of Mental Disorders, fourth edition was evaluated using the World Health Organization Composite International Diagnostic Interview. RESULTS: The cross-national lifetime and 12-month prevalence rates of specific phobia were, respectively, 7.4% and 5.5%, being higher in females (9.8 and 7.7%) than in males (4.9% and 3.3%) and higher in high- and higher-middle-income countries than in low-/lower-middle-income countries. The median age of onset was young (8 years). Of the 12-month patients, 18.7% reported severe role impairment (13.3-21.9% across income groups) and 23.1% reported any treatment (9.6-30.1% across income groups). Lifetime co-morbidity was observed in 60.5% of those with lifetime specific phobia, with the onset of specific phobia preceding the other disorder in most cases (72.6%). Interestingly, rates of impairment, treatment use and co-morbidity increased with the number of fear subtypes. CONCLUSIONS: Specific phobia is common and associated with impairment in a considerable percentage of cases. Importantly, specific phobia often precedes the onset of other mental disorders, making it a possible early-life indicator of psychopathology vulnerability.


Asunto(s)
Comorbilidad , Empleo/estadística & datos numéricos , Salud Global/estadística & datos numéricos , Salud Mental/estadística & datos numéricos , Trastornos Fóbicos/epidemiología , Factores Socioeconómicos , Adolescente , Adulto , Edad de Inicio , Femenino , Encuestas Epidemiológicas/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores Sexuales , Organización Mundial de la Salud , Adulto Joven
13.
Neotrop Entomol ; 46(1): 8-17, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27457373

RESUMEN

Wasps are able to synthesize toxic compounds known as venoms, which form a part of a mechanism to overcome prey and also to defend their colonies. Study of the compounds that constitute these substances is essential in order to understand how this defense mechanism evolved, since there is evidence that the venoms can vary both intra- and interspecifically. Some studies have used liquid and gas chromatography as a reliable technique to analyze these compounds. However, the use of Fourier transform infrared photoacoustic spectroscopy (FTIR-PAS) to analyze the variations in venom's chemical profile has been proposed recently. This study evaluated whether the FTIR-PAS technique is effective for assessing the role of environmental factors on intra- and interspecific differences in the venom of the wasps Polybia paulista Von Ihering and Polybia occidentalis Olivier by FTIR-PAS. The colonies were collected in three municipalities of Mato Grosso do Sul, Brazil, in different types of environments. The results showed that the venoms of P. paulista and P. occidentalis differed significantly in profile. In addition, the intraspecific differences in the venom's chemical profile of P. paulista are related to the type of environment where they nested, regardless of the geographical distance between the nests. The FTIR-PAS technique proved to be reliable and effective to evaluate the variations in the venom's chemical profile in social wasps.


Asunto(s)
Ponzoñas/química , Avispas , Animales , Brasil , Espectroscopía Infrarroja por Transformada de Fourier
14.
Epidemiol Psychiatr Sci ; 26(1): 89-101, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27066821

RESUMEN

AIMS: Important transformations in psychiatric healthcare (HC) delivery have been implemented in Latin America during the beginning of 21st century. However, information on current service uses patterns is scant, obstructing the estimates and proper planning of service needs for general population. The current investigation aims to describe patterns and estimates predictors of 12-month HC use by individuals with mental disorders in São Paulo metropolitan area, Brazil. METHOD: Data are from São Paulo Mental Health Survey, a cross-sectional multistage representative study. Participants were face-to-face interviewed in their household, using a structured diagnostic interview, the World Mental Health Survey Initiative version of the Composite International Diagnostic Interview. A total of 5037 respondents, non-institutionalised, aged 18 years and older were interviewed. The response rate was 81.3%. We determined the percentages of individuals with 12-month DSM-IV anxiety, mood and substance disorders that received treatment in the 12 months prior to assessment in main service sectors (specialty mental health, general medicine, human services (HS), and complementary and alternative medicine). The number of visits and percentage of individuals who received treatment at minimally adequacy also was estimated. Multilevel regression controlled contextual variables that influenced the use of service and treatment adequacy. RESULTS: Only 10.1% of respondents used some HC service in the 12 months prior to assessment for their psychiatric problems, including 3.9% of them being treated either by a psychiatrist, 3.5% by a non-psychiatrist mental health specialist, 3.3% by a general medical (GM) provider, 1.5% by a HS provider and 1.4% by a complementary and alternative medical provider. In general, those participants who received service in the mental health specialty sector reported more visits than those in the GM sector (median 3.9 v. 1.5 visits). The cases seen in specialty sector outnumber those visiting GM treatment in terms of minimally adequate treatment (54.6 v. 23.2%). The likelihood of receiving treatment was significantly greater among individuals diagnosed with any anxiety and mood disorder, presenting more severe disorders, and with possession of HC insurance. CONCLUSIONS: The great majority of individuals with an active mental disorder in São Paulo were either untreated or insufficiently treated. Awareness and training programmes to GM professionals are advocated to improve recognition, care take and referral to specialty care when needed. Proper integration among HC sectors is recommended.


Asunto(s)
Atención a la Salud/métodos , Disparidades en Atención de Salud , Trastornos Mentales/terapia , Servicios de Salud Mental/estadística & datos numéricos , Visita a Consultorio Médico/estadística & datos numéricos , Vigilancia de la Población/métodos , Población Urbana , Adolescente , Adulto , Brasil/epidemiología , Estudios Transversales , Femenino , Encuestas de Atención de la Salud , Humanos , Trastornos Mentales/epidemiología , Trastornos Mentales/psicología , Salud Mental , Prevalencia , Índice de Severidad de la Enfermedad , Factores Socioeconómicos , Adulto Joven
15.
Appl Opt ; 55(24): 6639-43, 2016 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-27556983

RESUMEN

A dispersive white-light Michelson interferometer was used to determine the wavelength dependence of the refractive index (n) in the visible range from 425 to 775 nm and the thermo-optical coefficient (dn/dT) of fused silica (FS) and borosilicate glass (BK7). For FS, the values obtained for n and dn/dT at 546 nm were 1.46079 and 11.3×10-6 K-1, respectively, while the values for BK7 glass were 1.51825 and 2.2×10-6 K-1, respectively, which is in good agreement with the literature. The accuracy of the methodology used for n was almost 10-6, enabling precise spectroscopic characterization of materials across a wide spectral range.

16.
Psychol Med ; 46(14): 2955-2970, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27484622

RESUMEN

BACKGROUND: Although mental disorders are significant predictors of educational attainment throughout the entire educational career, most research on mental disorders among students has focused on the primary and secondary school years. METHOD: The World Health Organization World Mental Health Surveys were used to examine the associations of mental disorders with college entry and attrition by comparing college students (n = 1572) and non-students in the same age range (18-22 years; n = 4178), including non-students who recently left college without graduating (n = 702) based on surveys in 21 countries (four low/lower-middle income, five upper-middle-income, one lower-middle or upper-middle at the times of two different surveys, and 11 high income). Lifetime and 12-month prevalence and age-of-onset of DSM-IV anxiety, mood, behavioral and substance disorders were assessed with the Composite International Diagnostic Interview (CIDI). RESULTS: One-fifth (20.3%) of college students had 12-month DSM-IV/CIDI disorders; 83.1% of these cases had pre-matriculation onsets. Disorders with pre-matriculation onsets were more important than those with post-matriculation onsets in predicting subsequent college attrition, with substance disorders and, among women, major depression the most important such disorders. Only 16.4% of students with 12-month disorders received any 12-month healthcare treatment for their mental disorders. CONCLUSIONS: Mental disorders are common among college students, have onsets that mostly occur prior to college entry, in the case of pre-matriculation disorders are associated with college attrition, and are typically untreated. Detection and effective treatment of these disorders early in the college career might reduce attrition and improve educational and psychosocial functioning.


Asunto(s)
Salud Global/estadística & datos numéricos , Trastornos Mentales/epidemiología , Salud Mental/estadística & datos numéricos , Estudiantes/estadística & datos numéricos , Universidades/estadística & datos numéricos , Organización Mundial de la Salud , Adolescente , Adulto , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Adulto Joven
17.
J Phys Condens Matter ; 28(31): 315402, 2016 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-27300313

RESUMEN

In situ micro-Raman spectroscopy was used to investigate the structural evolution of OH(-)-free calcium aluminosilicate glasses, under high pressure and at room temperature. Evaluation was made of the role of the SiO2 concentration in percalcic join systems, for Al/(Al + Si) in the approximate range from 0.9 to 0.2. Under high pressure, the intensity of the main band related to the bending mode of bridging oxygen ([Formula: see text][T-O-T], where T = Si or Al) decreased gradually, suggesting that the bonds were severely altered or even destroyed. In Si-rich glasses, compression induced a transformation of Q (n) species to Q (n-1). In the case of Al-rich glass, the Al in the smallest Q (n) units evolved from tetrahedral to higher-coordinated Al (([5])Al and ([6])Al). Permanent structural changes were observed in samples recovered from the highest pressure of around 15 GPa and, particularly for Si-rich samples, the recovered structure showed an increase of three-membered rings in the Si/Al tetrahedral network.

18.
Neotrop Entomol ; 45(1): 72-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26563402

RESUMEN

Apiculture in Brazil is quite profitable and has great potential for expansion because of the favorable climate and abundancy of plant diversity. However, the occurrence of pests, diseases, and parasites hinders the growth and profitability of beekeeping. In the interior of the state of São Paulo, apiaries are attacked by ants, especially the species Camponotus atriceps (Smith) (Hymenoptera: Formicidae), which use the substances produced by Apis mellifera scutellata (Lepeletier) (Hymenoptera: Apidae), like honey, wax, pollen, and offspring as a source of nourishment for the adult and immature ants, and kill or expel the adult bees during the invasion. This study aimed to understand the invasion of C. atriceps in hives of A. m. scutellata. The individuals were classified into castes and subcastes according to morphometric analyses, and their cuticular chemical compounds were identified using Photoacoustic Fourier transform infrared spectroscopy (FTIR-PAS). The morphometric analyses were able to classify the individuals into reproductive castes (queen and gynes), workers (minor and small ants), and the soldier subcaste (medium and major ants). Identification of cuticular hydrocarbons of these individuals revealed that the eight beehives were invaded by only three colonies of C. atriceps; one of the colonies invaded only one beehive, and the other two colonies underwent a process called sociotomy and were responsible for the invasion of the other seven beehives. The lack of preventive measures and the nocturnal behavior of the ants favored the invasion and attack on the bees.


Asunto(s)
Hormigas/anatomía & histología , Hormigas/química , Abejas , Animales , Brasil , Proteínas de Insectos/química
19.
Artículo en Inglés | MEDLINE | ID: mdl-25554953

RESUMEN

In the present paper the synthesis and optical characterization of iodinated acetophenone, 4-hydroxy-3-iodoacetophenone and 4-hydroxy-3,5-diiodoacetophenone obtained from 4-hydroxyacetophenone, were carried out. The optical features of iodinated molecules were determined by performing the UV-Vis absorption, fluorescence and thermal lens spectroscopies. The results showed that the optical properties of the 4-hydroxyacetophenone is altered when the iodine atom is inserted, as substituent, in the aromatic ring. Although it was determined that the optical feature was changed when one iodine atom was inserted in the aromatic ring (4-hydroxy-3-iodoacetophenone), the results revealed that emission behavior was strongly altered when two iodine atoms (4-hydroxy-3,5-diiodoacetophenone) were acting as substituents: the fluorescence quantum efficiency increases approximately 60%.


Asunto(s)
Acetofenonas/química , Halogenación , Teoría Cuántica , Soluciones , Espectrometría de Fluorescencia , Temperatura
20.
Genet Mol Res ; 13(4): 10035-48, 2014 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-25501215

RESUMEN

The cuticular chemical composition plays a significant role in the recognition of nest mates in social insects, thus functioning as a chemical signature of the colony. The structure of cuticular chemicals is subject to interference from genetic and exogenous factors, including diet. In this study, various colonies of the Ectatomma brunneum ant were removed from their natural environment and housed in a laboratory to monitor the response of the cuticular chemical composition to dietary changes. Analyses were performed using gas chromatography and Fourier transform infrared photoacoustic spectroscopy, which has not been previously used for this type of analysis. The results indicate that this method is useful for analyzing biological and natural systems. We observed changes in the chemical signature with food traces in the first 30 days under feed control. Therefore, genetic information may not be the only criterion that can be used to describe the chemical signature of a species; environmental variations also influence recognition signals. Furthermore, these results reinforce the reliability of the Fourier transform infrared photoacoustic spectroscopy method.


Asunto(s)
Hormigas/química , Dieta , Integumento Común/fisiología , Técnicas Fotoacústicas , Animales , Cromatografía de Gases , Análisis Discriminante , Ionización de Llama , Hidrocarburos/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Vibración
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