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1.
Braz J Biol ; 83: e273470, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37851770

RESUMO

The performance of three successive generations of Mahanarva spectabilis (Distant) (Hemiptera: Cercopidae) fed on four forages exposed to environments with different CO2 concentrations was evaluated. In the first bioassay, we utilized the following scenarios: A) plants and insects were kept at high and constant CO2 (700 ppm) and B) the insects were kept at CO2 700 ppm and fed on plants from the greenhouse (average of 390 ppm). In the second bioassay, we utilized the following scenarios: C) plants and insects were kept in a greenhouse and D) the insects were kept in the greenhouse and fed on plants kept at CO2 700 ppm. The survival and duration of the nymphal and adult stages and the number of eggs/female of M. spectabilis were evaluated. It was only possible to evaluate the cumulative effects of the increase of CO2 on three successive generations of M. spectabilis kept in a greenhouse, due to the reduced survival of the insects in the first generation in the laboratory. A greater direct than indirect effect of the CO2 level on the performance of M. spectabilis was observed. Furthermore, it should be considered that the effect of CO2 elevation on the survival, periods of development, and fecundity, when taken together, can significantly impact the population dynamics of M. spectabilis in future climate scenarios.


Assuntos
Brachiaria , Hemípteros , Animais , Dióxido de Carbono , Ninfa , Clima
2.
Carbohydr Polym ; 236: 116036, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32172852

RESUMO

Diclofenac sodium (DS) is an emergent pollutant, and among the methods investigated for its removal, adsorption is the most widely utilized technique. Hydroxyapatite and chitosan are biomaterials often used for adsorption. However, both biomaterials are limited due to their low chemical stability in an acidic medium; furthermore, pure hydroxyapatite interacts poorly with diclofenac. In this work, hydroxyapatite was organofunctionalized with 3-aminopropyltrimethoxysilane and further used to obtain amino hydroxyapatite /chitosan hybrids by crosslinking with glutaraldehyde at pH 3, 4, 5, and 6. X-ray diffraction patterns indicated the preservation of the hydroxyapatite phase under all pH conditions. Based on the control reaction of the amino hydroxyapatite with glutaraldehyde and its further reduction in sodium borohydride, the formation of CN moieties was highlighted as the main interaction mechanism between the aldehyde and amino groups. Therefore, crosslinking with glutaraldehyde was evaluated by infrared, Raman spectroscopy, and 13C NMR techniques; the results suggested contributions of imine formation and hydrogen bonding. The hybrid obtained at pH 3 exhibited an enhanced adsorption capacity of 125 mg g-1 at 15 min. The synergy between amino hydroxyapatite and chitosan crosslinked by glutaraldehyde was demonstrated.

3.
Chemosphere ; 242: 125109, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31675586

RESUMO

Organoclays have been applied as efficient adsorbents for pharmaceutical pollutants from aqueous solution. In this work, dodecylpyridinium chloride (C12pyCl) and hexadecylpyridinium chloride (C16pyCl) cationic surfactants were used for the preparation of organobentonites destined for diclofenac sodium (DFNa) adsorption, an anionic drug widely detected in wastewater. The organofunctionalization of the clay samples was performed under microwave irradiation at 50 °C for 5 min with surfactant amounts of 100% and 200% in relation to the cation exchange capacity (CEC) of the pristine bentonite. The amount of incorporated ammonium salts based on CHN elemental analysis was higher for all samples prepared with 200% of the CEC. The basal spacings of the organoclays ranged from 1.54 to 2.13 nm, indicating the entrance of organic cations into the interlayer spacing of the clay samples, and the spacing depended on the size of the alkyl organic chain. The hydrophobic character of the organobentonites was verified by thermogravimetry and infrared spectroscopy (FTIR). The adsorption isotherms showed that the drug capacity adsorption was influenced by the amount of surfactant incorporated into the bentonite, the packing density and the arrangement of the surfactants in the interlayer spacing. Zeta potential measurements of the organobentonites and FTIR analysis after drug adsorption suggested that electrostatic and nonelectrostatic interactions contributed to the mechanism of adsorption.


Assuntos
Bentonita/química , Diclofenaco/química , Adsorção , Anti-Inflamatórios não Esteroides/química , Cátions/química , Interações Hidrofóbicas e Hidrofílicas , Eletricidade Estática , Tensoativos/química , Água/química , Difração de Raios X
4.
5.
J Anim Sci ; 95(6): 2488-2495, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28727062

RESUMO

This study aimed to characterize the maximum heart rate (HR) and the intensity of official marcha contests (OMC) and to compare the cost of transport (COT) and metabolic power (Pmet) of Mangalarga Marchador (MM) horses of marcha batida (MB) and marcha picada (MP) gaits. Twenty-two MM horses participated in this study. The experiment was conducted in 3 phases: 1) maximum effort test (MET), 2) OMC, and 3) standardized marcha test (SMT). To characterize the HR, 19 horses (14 MB and 5 MP) underwent a MET. Of those, 13 (9 MB and 4 MP) were monitored during the OMC, which consisted of 4 stages: marcha, walk, functional trial, and rest. The average heart rate (HR) in each stage of the OMC was related to the HR to determine their relative intensity. The SMT was performed with 14 horses (9 MB and 5 MP), of which 11 had already participated in the previous stages. The COT and Pmet were calculated from the HR values obtained during the SMT. Blood samples were collected to analyze plasma lactate concentration ([Lac]). One-way ANOVA or 1-way repeated-measures ANOVA followed by the Tukey's test ( < 0.05) were used to analyze the results. The average HR was 211 ± 11 and 214 ± 11 beats/min (bpm) for the MB and MP groups, respectively, with no difference ( = 0.7066) between them. The [Lac] increased as a result of the MET ( < 0.05), with no difference between groups ( > 0.05). This indicated that horses of both groups had the same physical fitness levels. The OMC stages defined in our study differed ( < 0.05) regarding the relative intensity of the HR, except for the walk and standing stages, which were similar ( = 0.0875). The MP group presented greater COT ( = 0.0247) and Pmet ( = 0.0193). It can be concluded that the mean HR of MM horses (MB and MP) is 212 ± 11 bpm. The OMC of the MM breed can be characterized as an effort of intermittent and submaximal intensity. In addition, the locomotion of the MB horses is probably more energetically efficient than that of MP horses.


Assuntos
Metabolismo Energético , Marcha , Cavalos/fisiologia , Condicionamento Físico Animal , Animais , Feminino , Frequência Cardíaca/fisiologia , Ácido Láctico/sangue , Masculino , Descanso , Fatores de Tempo
7.
J Insect Sci ; 162016.
Artigo em Inglês | MEDLINE | ID: mdl-27012869

RESUMO

The aim of this study was to determine the favorable constant temperature range for Mahanarva spectabilis(Distant) (Hemiptera: Cercopidae) development as well as to generate geographic distribution maps of this insect pest for future climate scenarios. M. spectabilis eggs were reared on two host plants (Brachiaria ruziziensis(Germain and Edvard) and Pennisetum purpureum(Schumach)), with individual plants kept at temperatures of 16, 20, 24, 28, and 32 °C. Nymphal stage duration, nymphal survival, adult longevity, and egg production were recorded for each temperature*host plant combination. Using the favorable temperature ranges for M. spectabilis development, it was possible to generate geographic distribution. Nymphal survival was highest at 24.4 °C, with estimates of 44 and 8% on Pennisetum and Brachiaria, respectively. Nymphal stage duration was greater on Brachiaria than on Pennisetum at 20 and 24 °C but equal at 28 °C. Egg production was higher on Pennisetum at 24 and 28 °C than at 20 °C, and adult longevity on Pennisetum was higher at 28 °C than at 20 °C, whereas adult longevity at 24 °C did not differ from that at 20 and 28 °C. With these results, it was possible to predict a reduction in M. spectabilis densities in most regions of Brazil in future climate scenarios.


Assuntos
Aquecimento Global , Hemípteros/fisiologia , Animais , Brachiaria/parasitologia , Brasil , Hemípteros/crescimento & desenvolvimento , Longevidade/fisiologia , Ninfa/fisiologia , Oviposição/fisiologia , Pennisetum/parasitologia , Temperatura
8.
Arq. bras. med. vet. zootec ; 66(2): 635-639, Jan.-Apr. 2014. tab
Artigo em Português | LILACS | ID: lil-709310

RESUMO

The present study aimed to compare the morphometric measurements of Mangalarga Marchador horses of batida and picada marcha. Twenty-two linear and eight angular measurements of 222 males (130 of batida marcha and 92 of picada marcha) and 266 females (168 of batida marcha and 98 picada marcha) were compared in a completely randomized design, consisting of two treatments: horses of batida and picada marcha. The results were submitted to analysis of variance and means were compared by Fisher test (P<0.05). It was concluded that most of the measures of Mangalarga Marchador horses of batida and picada marcha have similar values, however, there are differences between some angles of members...


Assuntos
Animais , Masculino , Feminino , Fenômenos Biomecânicos , Biometria , Cavalos/anatomia & histologia , Marcha/fisiologia , Amplitude de Movimento Articular/fisiologia , Movimento/fisiologia
9.
J Econ Entomol ; 107(1): 396-402, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24665725

RESUMO

This study determined the number of spittlebug adults, Mahanarva spectabilis Distant (Hemiptera: Cercopidae), that should be used in selection tests of the forage grass, Brachiaria ruziziensis (Germain and Evrard). In this study, 0, 1, 2, 4, or 8 M. spectabilis adults were kept in plants for 4 or 8 d per experimental plot. After these periods, the insects were removed from the plants and chlorophyll content, damage score, dry weight, fresh weight, and percent dry matter of shoots were evaluated. Chlorophyll content decreased significantly with higher density of M. spectabilis in plants exposed to the pest for 4 or 8 d. Plants that were exposed to eight spittlebugs for 8 d showed a approximately 60% loss of chlorophyll content. When the forage was infested with eight adults for 4 d, the average damage score was 3 (50% of the leaf area was affected). The damage score and fresh and dry weights of the forage did not change depending on the exposure time of the plants to the spittlebugs. The percentage of dry matter of the plants infested was higher with the increase insect density and exposure time for all densities. Thus, the minimum recommended number is eight M. spectabilis adults for 4 d in resistance tests of B. ruziziensis to this pest species.


Assuntos
Brachiaria/fisiologia , Hemípteros , Animais , Distribuição Aleatória
10.
Neotrop Entomol ; 43(6): 526-31, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27194060

RESUMO

Behavioral patterns and pheromone titer in females of the steam borer Diatraea indigenella Dyar & Heinrich were assessed for 7 days during scotophase under a 13:11 L:D photoperiod. Calling was observed from the first scotophase for most of the females. The highest percentage of calling females was recorded 6 h after the onset of scotophase. Calling bouts and length of calling were affected by age, decreasing dramatically after the sixth scotophase. By coupling chemical and electrophysiological techniques (GC-EAD, GC-MS) and olfactometer bioassays (Z,E)-9,11-hexadecadienal was identified as the main sex pheromonal component in the extracts of female glands. The concentration varied from 2.53 to 13.7 ng gland(-1) with a peak at the 6th hour of scotophase. In addition, two unidentified secondary active components were detected at very low concentrations. Behavioral assays showed that 86% of the male moths were more attracted to the gland extracts than to hexane (control), and 77% of the male moths were more attracted to the gland extract than to the synthetic major component (Z,E)-9,11-hexadecadienal. However, 68% of males preferred the synthetic major component over hexane. The identification of the major sex pheromonal component represents an important step toward the complete elucidation of the composition of the sex pheromone of D. indigenella in order to develop monitoring tools.


Assuntos
Comunicação Animal , Mariposas , Atrativos Sexuais , Animais , Feminino , Masculino , Feromônios , Reprodução
11.
Int J Biol Macromol ; 61: 471-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23973496

RESUMO

Chitosan-montmorillonite (KSF-CTS) beads were prepared by crosslinking with pentasodium tripolyphosphate (TPP). Montmorillonite (KSF-Na), CTS and KSF-CTS biocomposite were used to remove Cu(II) from aqueous solutions. These materials were characterized before and after copper adsorption by XRD, FTIR and thermogravimetry (TG). The data indicated that the adsorption process proceeds kinetically according to a pseudo-second-order model. The adsorption processes were adjusted to the Langmuir model for KSF-Na and CTS and to the Temkin model for KSF-CTS. The maximum adsorption capacity followed the order CTS>KSF-CTS>KSF-Na. Percentages desorption of copper ions from the KSF-CTS composite after three desorption cycles were 86%, 85% and 84%, respectively, using EDTA as regeneration agents.


Assuntos
Bentonita/química , Cátions/química , Quitosana/química , Cobre/química , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Purificação da Água , Difração de Raios X
12.
Artigo em Inglês | LILACS | ID: lil-508230

RESUMO

The present work aimed to determine the oral microbiotic composition of snakes from São José do Rio Preto city, São Paulo State, Brazil. Ten snake species, comprising the families Boidae, Colubridae, Elapidae and Viperidae, were submited to microbiological examination of their oral cavity, which indicated positivity for all buccal samples. Gram-negative bacilli, gram-negative cocci bacilli, grambacilli and gram-positive cocci were isolated from the snakes. Among isolated bacterium species, the occurrence of coagulase-negative staphylococci in the buccal cavity of Crotalus durissus (Viperiade), Eunectes murinus (Boidae), Mastigodryas bifossatus (Colubridae) and Bacillus subtilis, common to oral cavity of Bothrops alternatus (Viperidae) and Phalotris mertensi (Colubridae), was detected. It was observed higher diversity of isolated bacteria from the oral cavity of Micrurus frontalis (Elapidae) and Philodryas nattereri (Colubridae), as well as the prevalence of gram-positive baccillus and gram-positive cocci. The composition of the oral microbiota of the studied snakes, with or without inoculating fangs, is diverse and also related to the formation of abscesses at the bite site in the victims of the ophidian accidents, and to pathogenic processes in the snakes that host these microorganisms


Assuntos
Animais , Boidae , Bactérias/isolamento & purificação , Boca/microbiologia , Colubridae , Viperidae , Brasil
13.
AIDS ; 19(13): w1-6, 2005 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-16103763

RESUMO

Research teams from five countries, Brazil, China, Kenya, Peru and Thailand, have initiated a policy-maker survey on vaccine delivery, cost studies for future HIV vaccination programmes, and associated simulation modeling exercises analysing the relative cost-effectiveness of potential HIV vaccination strategies. The survey assesses challenges and opportunities for future country-level HIV vaccination strategies, providing data on the vaccine characteristics (e.g. vaccine efficacies for susceptibility, infectiousness and disease progression) and vaccination programme strategies to be considered in the cost-effectiveness modeling analyses. The study will provide decision-makers with modeling data on vaccination policy considerations that will assist in developing country-level capacities for future HIV vaccine policy adoption and effective delivery systems, and will help delineate the long-term financial requirements for sustainable HIV vaccination programmes. The WHO-UNAIDS HIV Vaccine Initiative and the collaborating researchers welcome comments or questions from policy makers, health professionals and other stakeholders in the public and private sectors about this effort to help advance policy and capacity related to future potential HIV vaccines.


Assuntos
Vacinas contra a AIDS/economia , Infecções por HIV/prevenção & controle , Programas de Imunização/economia , Vacinas contra a AIDS/provisão & distribuição , Simulação por Computador , Análise Custo-Benefício , Atenção à Saúde , Infecções por HIV/economia , Pesquisas sobre Atenção à Saúde , Política de Saúde , Acessibilidade aos Serviços de Saúde , Humanos , Cooperação Internacional , Modelos Econométricos , Formulação de Políticas
14.
J. venom. anim. toxins ; 8(1): 102-111, 2002. ilus, tab
Artigo em Inglês | LILACS | ID: lil-303725

RESUMO

The objective of this clinical study was to evaluate local tissue damage caused by Bothrops sp envenoming in relation to lesion type and damaged tissues using magnetic resonance imaging (MRI). Fifteen patients bitten by Bothrops snakes were treated at the Emergency Unit of the Tropical Diseases Unit at the University Hospital, Botucatu School of Medicine, UNESP, Säo Paulo State, Brazil. After receiving specific serotherapy, the patients were submitted to MR of the bite site. T1 spin-echo MRI were obtained revealing the following lesions: edema (n=9), edema associated with hemorrhage (n=5), and hemorrhage (n=1). Perimuscular areas (n=6) and subcutaneous tissues (n=5) were the most affected, followed by muscular tissues (n=4). It is important to mention that MRI did not show myonecrosis of the bite site, a widely reported finding in anatomical and histopathological experimental studies.


Assuntos
Humanos , Masculino , Feminino , Criança , Idoso , Adolescente , Adulto , Pessoa de Meia-Idade , Bothrops , Brasil , Imageamento por Ressonância Magnética/classificação , Pele , Mordeduras de Serpentes , Venenos de Crotalídeos/efeitos adversos , Lesões dos Tecidos Moles/fisiopatologia
16.
Cad Saude Publica ; 16(## Suppl 1): 77-87, 2000.
Artigo em Português | MEDLINE | ID: mdl-10904391

RESUMO

This article analyzes the temporal distribution of reported AIDS cases by level of education used as a proxy variable for individual socioeconomic status. All AIDS cases aged 20-69 years and reported through May 29, 1999, with date of diagnosis between 1986-1996, were included in the study. Incidence rates were calculated for men and women according to level of education ("level 1" up to 8 years of schooling and "level 2" with over 8 years of schooling), by five geographic regions, and by year of diagnosis. Incidence rates for men with less schooling were close to or higher than those for men with more schooling (particularly in the Southeast region). For women, a time series showed that incidence rates increased at a higher rate among women with less schooling in all regions of the country; in the Southeast, the incidence rate for women with less schooling was already greater than for women with more schooling by 1989. According to the present analysis, the AIDS epidemic in Brazil began among people from the more highly educated social strata and progressed steadily through to the less educated social strata, especially among women.


Assuntos
Síndrome da Imunodeficiência Adquirida/epidemiologia , Escolaridade , Síndrome da Imunodeficiência Adquirida/diagnóstico , Adulto , Idoso , Brasil/epidemiologia , Notificação de Doenças , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Classe Social , Fatores Socioeconômicos
17.
Am J Epidemiol ; 133(7): 748-52, 1991 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2018029

RESUMO

The authors carried out a critical assessment of the literature to learn about the extent of use of the case-control method in outbreak investigations, and to identify problems observed in the use of this method to investigate outbreaks. The literature search comprised reports of outbreak investigations from the MEDLINE system, Morbidity and Mortality Weekly Report, and six epidemiologic and medical journals. The proportion of these reports that used the case-control method increased from one article out of 519 in the 1960-1965 period to 144 out of 845 reported outbreaks in the 1980-1985 period. A comparison of the case-control studies of outbreak investigations in the 1970-1975 period with those in the 1980-1985 period revealed relatively more sophisticated methods of analysis in the latter period.


Assuntos
Estudos de Casos e Controles , Surtos de Doenças , Métodos Epidemiológicos , Humanos , Sistemas de Informação
18.
Arq Neuropsiquiatr ; 45(1): 53-9, 1987 Mar.
Artigo em Português | MEDLINE | ID: mdl-3300614

RESUMO

A case of Creutzfeldt-Jakob disease (CJD) in a 76 year-old man is presented. The clinical picture included a rapid progressive dementia associated with ataxia, global aphasia, myoclonus and pyramidal signs; death occurred after about 4 months. There was an antecedent of chemical trauma caused by plant liquid on right eye 12 to 18 months before. The electroencephalogram showed diffuse slow activity and the neuropathological findings were typical. The detection of a protein called "prion" or PrP27-30 in the scrapie and the finding that some proteins isolated from brain of patients with CJD have reacted with antibodies raised against it have improved the knowledge about the infectious agent. The recent reports of young patients with CJD after human growth hormone therapy prepared from pools of pituitary glands obtained at autopsy are alarming and probably new cases will be described.


Assuntos
Córtex Cerebral/patologia , Síndrome de Creutzfeldt-Jakob/patologia , Idoso , Síndrome de Creutzfeldt-Jakob/fisiopatologia , Síndrome de Creutzfeldt-Jakob/transmissão , Humanos , Masculino , Degeneração Neural , Príons/patogenicidade
19.
Arq Neuropsiquiatr ; 44(2): 195-200, 1986 Jun.
Artigo em Português | MEDLINE | ID: mdl-2879524

RESUMO

A case of polyarteritis nodosa (PAN) in a 54 year-old man is presented. The clinical picture showed a 6-month history of mixed sensorimotor distal symmetrical polyneuropathy in all limbs together with anorexia, weight loss, fatigue, arthralgia, myalgia, mild fever and hypertension. The laboratory studies showed leucocytosis, elevated ESR, positive HBsAg and presence of cryoglobulins. Selective renal, celiac and mesenteric angiography was performed by femoral approach and has showed innumerable aneurysms most of them in hepatic and renal circulation. After about two weeks death has occurred. A brief discussion is done on clinical aspects of PAN pointing out the importance of HBsAg determination on etiopathogenesis and angiographic study on diagnosis.


Assuntos
Poliarterite Nodosa/diagnóstico , Aneurisma/complicações , Aneurisma/diagnóstico por imagem , Angiografia , Antígenos de Superfície da Hepatite B/análise , Humanos , Masculino , Pessoa de Meia-Idade , Poliarterite Nodosa/complicações , Poliarterite Nodosa/imunologia , Artéria Renal/diagnóstico por imagem
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