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1.
Braz J Biol ; 84: e282231, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38808790

RESUMEN

The technique of terrestrial sampling of boll weevil (BW) populations is expensive and inefficient over large areas, but may be cheaper and more efficient without involving the manipulation of cotton squares. The aim of this study was to develop a technique to sampling cotton squares based on the observation of opened and/or yellowing bracts to determine the need and efficacy of chemical control of BW in cotton crops. The first experiment aimed to estimate the ratio between the number of cotton squares with opened and/or yellowed bracts and that of squares with BW oviposition punctures. The second experiment, aimed to determine the efficacy of chemical control for BW by sampling cotton squares with opened and/or yellowed bracts. The ratio between the number of opened and/or yellowed bracts and the number of cotton squares with oviposition punctures was 2:1. The level and efficiency of chemical control of BW, based on the percentage and sampling of cotton plants with opened and/or yellowed bracts, was 5% and did not differ from the one based on the observation of cotton plants with 10% cotton squares with oviposition punctures by BW females. The control level based on sampling cotton plants with open and/or yellowing bracts was 5%. The efficiency of chemical insecticides using this economic threshold against the BW did not differ from that based on sampling cotton plants with 10% of cotton squares with oviposition punctures by BW females. This indicates that the chemical control of cotton boll weevil can be carried out based on cotton squares with open and/or yellowed bracts.


Asunto(s)
Gossypium , Control de Insectos , Oviposición , Gorgojos , Gorgojos/fisiología , Gossypium/parasitología , Animales , Oviposición/fisiología , Femenino , Control de Insectos/métodos , Insecticidas
2.
Arq. bras. med. vet. zootec. (Online) ; 74(1): 43-50, Jan.-Feb. 2022. tab, ilus
Artículo en Inglés | VETINDEX | ID: biblio-1374396

RESUMEN

Dogs and cats are frequently affected by gastrointestinal parasites of medical and veterinary concern. The correct diagnosis is pivotal to the treatment outcome, reducing the risk of environmental contamination and spreading of these pathogens. The aim of this study was to determine the prevalence of gastrointestinal parasites of domiciled dogs and cats in an urban area of Northeastern Brazil, as well as to discuss the findings from a "One Health" perspective. Fecal samples (n = 231) of dogs (n = 126) and cats (n = 105) were obtained directly from the environment after spontaneous defecation, and subsequently analyzed through the Mini-FLOTAC and Baermann techniques. Of all samples, 28.14% (65/231) presented immature forms of gastrointestinal parasites, with 31.75% (40/126) and 23.81% (25/105) of dogs and cats positive, respectively (x 2 = 1.413; p = 0.2345). Two genera of helminths (Ancylostoma and Toxocara) and two genera of protozoa (Cystoisospora and Entamoeba) were identified. Additionally, co-infections were observed in 15% (6/40) of positive dogs and 28% (7/25) of positive cats (p = 0.2207). None metastrongyloid larvae were detected. In conclusion, animals herein assessed presented a high prevalence of zoonotic gastrointestinal nematodes. Therefore, preventive measures against these neglected parasites should be stimulated.


Cães e gatos são frequentemente afetados por parasitos gastrointestinais de interesse médico e veterinário. Em áreas urbanas, onde esses animais apresentam uma relação próxima com o homem, o diagnóstico correto é fundamental para o resultado do tratamento, reduzindo o risco de contaminação ambiental e de disseminação desses patógenos. O objetivo deste estudo foi determinar a prevalência de parasitos gastrointestinais infectando cães e gatos domiciliados em uma área urbana do Nordeste do Brasil, bem como discutir os achados sob a perspectiva de "Saúde Única". Amostras fecais (n = 231) de cães (n = 126) e gatos (n = 105) foram obtidas diretamente do meio ambiente após a defecação espontânea e, posteriormente, analisadas pelas técnicas Mini-FLOTAC e Baermann. Do total de amostras, 28,14% (65/231) apresentaram formas imaturas de parasitos gastrointestinais (ovos, cistos ou oocistos), com 31,75% (40/126) e 23,81% (25/105) de cães e gatos positivos, respectivamente (x2 = 1,413; P = 0,2345). Dois gêneros de helmintos (Ancylostoma e Toxocara) e dois gêneros de protozoários (Cystoisospora e Entamoeba) foram identificados em cães e gatos. Além disso, coinfecções foram observadas em 15% (6/40) dos cães positivos e em 28% (7/25) dos gatos positivos (P = 0,2207). Nenhuma larva de metastrongilídeo foi detectada. Em conclusão, os animais aqui avaliados apresentaram alta prevalência de nematódeos gastrointestinais de importância zoonótica. Portanto, medidas preventivas contra esses parasitos negligenciados devem ser estimuladas.


Asunto(s)
Animales , Gatos , Perros , Parásitos/aislamiento & purificación , Enfermedades Parasitarias en Animales/epidemiología , Enfermedades de los Gatos/epidemiología , Enfermedades de los Perros/epidemiología , Toxocara/aislamiento & purificación , Brasil/epidemiología , Eucoccidiida/aislamiento & purificación , Entamoeba/aislamiento & purificación , Salud Única , Ancylostoma/aislamiento & purificación
3.
Arq. bras. med. vet. zootec. (Online) ; 73(1): 55-61, Jan.-Feb. 2021. tab, mapas
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1153051

RESUMEN

The number of domestic animals living with human beings is rapidly increasing in parallel with an enhanced risk of transmission of their parasites and the pathogens they might carry. The aim of this study was to assess the occurrence of hematophagous arthropods infesting domestic animals from Northeastern Brazil and to remark the implications of their occurrence on the epidemiology and control of selected veterinary and human diseases. From January 2017 to April 2019, ectoparasites infesting domestic cats, dogs and horses were collected for their respective hosts and identified. Overall, ectoparasites were sampled from 86 domestic animals, living in different anthropic settings. A total of 401 specimens (344 ticks and 57 fleas) were collected from different hosts [i.e., 10 (2.49%), 96 (23.94%) and 295 (73.57%) from cats, dogs and horses, respectively]. Two flea (i.e., Ctenocephalides canis and Ctenocephalides felis) and 5 tick species (i.e., Amblyomma ovale, Amblyomma sculptum, Dermacentor nitens, Rhipicephalus microplus and Rhipicephalus sanguineus sensu lato) were identified. This study provides data on the ectoparasite fauna infesting domestic animals from Northeastern Brazil. The diagnosis and treatment of these parasites should not be underestimated, considering the role that hematophagous arthropods display as vectors of pathogens of medical and veterinary concern.(AU)


O número de animais domésticos infestados por ectoparasitos vivendo em estreito contato com seres humanos está aumentando, elevando o risco de infecção pelos patógenos transmitidos por vetores. Objetivou-se neste estudo avaliar a ocorrência de ectoparasitos infestando animais do nordeste do Brasil e discutir as implicações desse parasitismo na epidemiologia e no controle de doenças de importância médico-veterinária. De janeiro de 2017 a abril de 2019, artrópodes foram coletados de gatos, cães e cavalos, e identificados morfologicamente. Ectoparasitos foram removidos de 86 animais infestados provenientes de áreas urbanas e rurais. Foram identificados 401 espécimes (344 carrapatos e 57 pulgas) coletados de diferentes hospedeiros (10 (2,49%), 96 (23,94%) e 295 (73,57%) de gatos, cães e cavalos, respectivamente. Duas espécies de pulgas (Ctenocephalides canis e Ctenocephalides felis) e cinco espécies de carrapatos (Amblyomma ovale, Amblyomma sculptum, Dermacentornitens, Rhipicephalus microplus e Rhipicephalus sanguineus sensu lato) foram identificadas. Este estudo fornece informações sobre a ectofauna de animais domésticos do nordeste do Brasil. Portanto, o diagnóstico e o tratamento desses parasitos não devem ser subestimados, considerando que os artrópodes aqui relatados podem veicular patógenos de importância médico-veterinária.(AU)


Asunto(s)
Humanos , Animales , Gatos , Perros , Garrapatas , Infestaciones Ectoparasitarias/epidemiología , Siphonaptera , Caballos/parasitología , Brasil , Zoonosis/epidemiología , Rhipicephalus , Ctenocephalides , Salud Única , Amblyomma
4.
Artículo en Inglés | MEDLINE | ID: mdl-25871146

RESUMEN

A detailed quantitative analysis of the specific heat in the 0.5- to 200-K temperature range for almost dry L-cysteine and its dimer, L-cystine, amino acids is presented. We report the occurrence of a sharp first-order transition at ∼76 K for L-cysteine associated with the thiol group ordering which was successfully modeled with the two-dimensional Ising model. We demonstrated that quantum rotors, two-level systems (TLS), Einstein oscillators, and acoustic phonons (the Debye model) are essential ingredients to correctly describe the overall experimental data. Our analysis pointed out the absence of the TLS contribution to the low temperature specific heat of L-cysteine. This result was similar to that found in other noncrystalline amorphous materials, e.g., amorphous silicon, low density amorphous water, and ultrastable glasses. L-cystine presented an unusual nonlinear acoustic dispersion relation ω(q)=vq0.95 and a Maxwell-Boltzmann-type distribution of tunneling barriers. The presence of Einstein oscillators with ΘE∼70 K was common in both systems and adequately modeled the boson peak contributions.


Asunto(s)
Cisteína/química , Cistina/química , Calor , Dimerización , Transición de Fase , Teoría Cuántica
5.
Artículo en Inglés | MEDLINE | ID: mdl-25353517

RESUMEN

Some physical properties of hydrated biomolecules, e.g., the occurrence of a boson peak, have been recognized to resemble those of glassy states. The present work shows that quantum fluctuations play a fundamental role in describing the glassy state of biomolecules, particularly at lower hydration levels. There is a linear relationship between the quantumness and the slope of the temperature dependence of the boson peak frequency, which is used to classify the extent of quantum contributions to the glassy state of glasses in general. Lastly, we demonstrate that the boson peak two-band spectral structure that is observed in some cases can be directly linked to the anisotropy of the elastic properties of the material. The amino acid L-cysteine is studied in detail. The findings are compared with previously reported data for other macromolecules.


Asunto(s)
Biopolímeros/química , Cisteína/química , Interacciones de Partículas Elementales , Modelos Químicos , Modelos Estadísticos , Teoría Cuántica , Simulación por Computador , Transición de Fase , Temperatura , Vibración
6.
J Microsc ; 250(3): 218-27, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23557383

RESUMEN

This in vitro study aimed to quantify water loss at histological points in ground sections of normal enamel during air drying at room temperature (25°C) and relative humidity of 50%. From each of 10 ground sections of erupted permanent human normal enamel, three histological points (n = 30) located at 100, 300 and 500 µm from enamel surface and along a transversal following prisms paths were characterized regarding the mineral, organic and water volumes. Water loss during air drying was from 0 to 48 h. Drying occurred with both falling and constant-drying rates, and drying stabilization times (Teq ) ranged from 0.5 to 11 h with a mean 0.26 (±0.12)% weight loss. In some samples (n = 5; 15 points), Teq increased as a function of the distance from the enamel surface, and drying occurred at an apparent diffusion rate of 3.47 × 10⁻8 cm² s⁻¹. Our data provide evidence of air drying resulting in air replacing enamel's loosely bound water in prisms sheaths following a unidirectional water diffusion rate of 3.47 × 10⁻8 cm² s⁻¹ (from the original enamel surface inward), not necessarily resulting in water evaporating directly into air, with important implications for transport processes and optical and mechanical properties.


Asunto(s)
Esmalte Dental/química , Desecación , Agua/análisis , Aire , Humanos , Humedad , Diente Molar/química , Temperatura
7.
J Phys Condens Matter ; 24(19): 195104, 2012 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-22499214

RESUMEN

Two special dynamical transitions of universal character have recently been observed in macromolecules (lysozyme, myoglobin, bacteriorhodopsin, DNA and RNA) at T* ~100-150 K and T(D) ~180-220 K. The underlying mechanisms governing these transitions have been the subject of debate. In the present work, a survey is reported on the temperature dependence of structural, vibrational and thermodynamical properties of a nearly anhydrous amino acid (orthorhombic polymorph of the amino acid l-cysteine at a hydration level of 3.5%). The temperature dependence of x-ray powder diffraction patterns, Raman spectra and specific heat revealed these two transitions at T* = 70 K and T(D) = 230 K for this sample. The data were analyzed considering amino acid-amino acid, amino acid-water, water-water phonon-phonon interactions and molecular rotor activation. Our results indicated that the two referred temperatures define the triggering of very simple and particular events that govern all the interactions of the biomolecular: activation of CH(2) rigid rotors (T < T* ), phonon-phonon interactions between specific amino acid and water dimer vibrational modes (T* < T < T(D)), and water rotational barriers surpassing (T > T(D)).


Asunto(s)
Cisteína/química , Transición de Fase , Modelos Moleculares , Conformación Molecular , Compuestos de Sulfhidrilo/química , Temperatura , Termodinámica , Vibración
8.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;45(2): 104-112, Feb. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-614579

RESUMEN

Few studies have reported the molecular epidemiological characterization of HIV-1 in the Northern region of Brazil. The present study reports the molecular and epidemiological characterization of 31 HIV-1 isolates from blood donors from the State of Amazonas who donated blood between April 2006 and March 2007. Serum/plasma samples from all donors were screened for HIV antibodies by ELISA and the results confirmed by Western blot analysis. Genomic DNA was extracted from the buffy coat using the Super Quik-Gene-DNA Isolation kit. Nested PCR was performed on the env, gag, and pol regions of HIV-1 using the Gene Amp PCR System 9700. Sequencing reactions were performed using the inner PCR primers and the DYEnamic™ ET Dye Terminator Kit, and phylogenetic analysis was performed using the gag, pol, and env gene sequences. We collected samples from 31 blood donors who tested positive for HIV-1 in confirmatory experiments. The male:female ratio of blood donors was 3.4:1, and the mean age was 32.4 years (range: 19 to 61 years). Phylogenetic analysis showed that subtype B is the most prevalent among Northern Brazilian HIV-1-seropositive blood donors. One HIV-1 subtype C and one circulating recombinant form (CRF_BF) of HIV-1 were identified in the State of Amazonas. This is the first study showing the occurrence of a possible "homogenous" subtype C in this region of Brazil. This finding could contribute to a better characterization of the HIV-1 strains that circulate in the country.


Asunto(s)
Adulto , Femenino , Humanos , Persona de Mediana Edad , Adulto Joven , Donantes de Sangre , Infecciones por VIH/virología , VIH-1 , Secuencia de Bases , Western Blotting , Brasil/epidemiología , Ensayo de Inmunoadsorción Enzimática , Genes env/genética , Genes gag/genética , Genes pol/genética , Infecciones por VIH/epidemiología , VIH-1 , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa
9.
Braz J Med Biol Res ; 45(2): 104-12, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22249428

RESUMEN

Few studies have reported the molecular epidemiological characterization of HIV-1 in the Northern region of Brazil. The present study reports the molecular and epidemiological characterization of 31 HIV-1 isolates from blood donors from the State of Amazonas who donated blood between April 2006 and March 2007. Serum/plasma samples from all donors were screened for HIV antibodies by ELISA and the results confirmed by Western blot analysis. Genomic DNA was extracted from the buffy coat using the Super Quik-Gene-DNA Isolation kit. Nested PCR was performed on the env, gag, and pol regions of HIV-1 using the Gene Amp PCR System 9700. Sequencing reactions were performed using the inner PCR primers and the DYEnamic™ ET Dye Terminator Kit, and phylogenetic analysis was performed using the gag, pol, and env gene sequences. We collected samples from 31 blood donors who tested positive for HIV-1 in confirmatory experiments. The male:female ratio of blood donors was 3.4:1, and the mean age was 32.4 years (range: 19 to 61 years). Phylogenetic analysis showed that subtype B is the most prevalent among Northern Brazilian HIV-1-seropositive blood donors. One HIV-1 subtype C and one circulating recombinant form (CRF_BF) of HIV-1 were identified in the State of Amazonas. This is the first study showing the occurrence of a possible "homogenous" subtype C in this region of Brazil. This finding could contribute to a better characterization of the HIV-1 strains that circulate in the country.


Asunto(s)
Donantes de Sangre , Infecciones por VIH/virología , VIH-1/genética , Adulto , Secuencia de Bases , Western Blotting , Brasil/epidemiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Genes env/genética , Genes gag/genética , Genes pol/genética , Infecciones por VIH/epidemiología , VIH-1/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Adulto Joven
10.
Scand J Immunol ; 73(5): 486-95, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21231952

RESUMEN

The rational of this study we intended to investigate whether the peripheral blood immunological/virological biomarkers were associated with distinct patterns of sleeping quality in patients with chronic hepatitis C-(HCV). Distinct well-established indexes/scores were used to categorize the sleeping quality of HCV patients, including the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale and Fatigue Severity Scores. Our findings demonstrated that HCV patients classified as 'good sleeper' displayed an enhanced frequency of circulating CD8(+) T cells, lower frequency of activated (CD69(+)) neutrophils and eosinophils but enhanced frequency of activated lymphocytes besides lower seric levels of IL-4/IL-8/IL-10 but higher levels of IL-12, besides lower HCV virus load and lower anti-HCV IgG levels. In contrast, HCV patients classified as 'poor sleeper' displayed enhanced levels of activated neutrophils and eosinophils but lower frequency of activated lymphocytes, higher seric levels of IL-6/TNF-α/IL-10 but lower levels of IL-12 besides higher HCV virus load and increased anti-HCV IgG levels. Positive correlation was further confirmed by the relationship between the leucocyte activation status, the cytokine levels, the HCV viral load and the anti-HCV IgG reactivity with the PSQI indexes. Analysis of cytokine signature curves demonstrated that lower frequency of IL-10 was observed in HCV patients classified as 'good sleepers', whereas enhanced frequency of IL-6 was found HCV patients classified as 'poor sleepers'. In conclusion, our data suggest that immunological biomarkers (leucocytes activation status and seric cytokines levels) are likely to be associated with sleeping quality patterns in HCV patients, suggesting their putative use for clinical monitoring purposes.


Asunto(s)
Hepacivirus/inmunología , Hepatitis C Crónica/sangre , Trastornos del Sueño-Vigilia/sangre , Adulto , Anciano , Biomarcadores/sangre , Citocinas/genética , Citocinas/inmunología , Femenino , Citometría de Flujo , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/virología , Humanos , Inmunofenotipificación , Masculino , Persona de Mediana Edad , ARN Viral/química , ARN Viral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trastornos del Sueño-Vigilia/inmunología , Trastornos del Sueño-Vigilia/virología , Subgrupos de Linfocitos T/inmunología , Linfocitos T/inmunología , Adulto Joven
11.
Artículo en Inglés | MEDLINE | ID: mdl-19802756

RESUMEN

The aim of this study was to determine the levels of Penicillium citreonigrum and citreoviridin present in rice samples from Maranhão State, Brazil, where an outbreak of beriberi was reported and 32 deaths occurred (7% of the notified cases died in 2006). The ability of P. citreonigrum to produce citreoviridin was assessed, and a total of 420 samples of 21 different kinds of rice were collected. Mycobiota isolation and identification, the ability of citreoviridin strains to produce toxin, and the natural occurrence of citreoviridin were established. Rice samples were found to have high fungal counts and showed increasing levels from 2004 to 2007 harvest years. The most frequent genus was Aspergillus followed by Penicillium and Cladosporium. Ten out of eleven strains of P. citreonigrum were able to produce citreoviridin. Three rice samples had levels of citreoviridin ranging from 12 to 96.7 ng g(-1), and two bran samples had levels of 128 and 254 ng g(-1). These samples contaminated with P. citreonigrum and citreoviridin were involved in the beriberi cases from Maranhão State. Monitoring rice for mycotoxins in areas where this substrate is the basic food is crucial to prevent outbreaks like the one reported in this study, to improve management practice, and to diminish exposure risk of humans to these harmful toxins.


Asunto(s)
Aurovertinas/metabolismo , Beriberi/epidemiología , Oryza , Penicillium/metabolismo , Brasil/epidemiología , Cromatografía Líquida de Alta Presión , Brotes de Enfermedades , Humanos
12.
J Environ Radioact ; 101(1): 75-81, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19800154

RESUMEN

Natural gamma radiation measurements of sand deposits were carried out in order to study the chronology of prehistoric colonization of the Brazilian coast during the Holocene. The method employs thorium, uranium and potassium as tracers of the geological provenance of Quaternary deposits, where artificial shellmounds are found. The so-called sambaquis are archaeological settlements, characteristic of fisher-gatherers, specialized in the exploitation of shellfish. Our results show a considerable positive correlation between the formation of coastal deposits, based on cross plots of eTh/eU and eTh/K, and the antiquity of its prehistoric human occupation.


Asunto(s)
Rayos gamma , Sedimentos Geológicos/química , Datación Radiométrica/métodos , Brasil , Potasio/análisis , Monitoreo de Radiación/métodos , Trazadores Radiactivos , Mariscos/análisis , Dióxido de Silicio/química , Torio/análisis , Uranio/análisis , Residuos/análisis
13.
Hist Cienc Saude Manguinhos ; 2(3): 44-96, 1995.
Artículo en Portugués | MEDLINE | ID: mdl-16688904

RESUMEN

Archeological diggings in household garbage deposits from nineteenth-century Rio have uncovered an abundance of equipment used in the elimination of fecal material and phlegm. These findings formed the basis for an analysis and interpretation of the era's attitudes regarding body fluids, as adopted when the mentalities of the new 'bourgeois' segments - then undergoing a process of rise and consolidation - were impregnated by Hippocratic humoralism. The text shows how the introduction of a 'body order' was fundamental in building and keeping the social order in the nineteenth century. It likewise shows how the ideology of hygienization was one of the most important and efficacious strategies for underpinning the bourgeoisie's (victorious) project to achieve hegemony.


Asunto(s)
Líquidos Corporales , Humoralismo , Higiene , Odorantes , Clase Social , Población Urbana , Arqueología , Brasil/etnología , Historia del Siglo XIX , Higiene/economía , Higiene/historia , Odorantes/prevención & control , Controles Informales de la Sociedad/historia , Controles Informales de la Sociedad/métodos , Población Urbana/clasificación , Población Urbana/historia , Población Urbana/tendencias
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