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1.
Braz J Biol ; 83: e275439, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422263

RESUMO

Visceral Leishmaniasis is included among the neglected tropical diseases, being directly related to conditions of social vulnerability, in urban environments, dogs act as important reservoirs. The aim of the study was to evaluate the distribution of dogs, related risk factors and identify of volatile organic compounds from infected dogs. Peripheral blood samples from 72 dogs were collected for detection using the ELISA test, in addition to hair samples for analysis by GC-MS. Of the evaluated dogs, 13 (18.05%/72) were reactive for canine VL, seven in Aracaju and six in Propriá. Factors related to vegetation, age, place where the dog stays and free access to the street, were associated with a greater chance of the dog becoming infected. Fifty-three compounds were identified from ten canine hair samples, among which 2-butoxyethanol, benzaldehyde, decane, 2-phenylacetaldehyde, nonan-1-ol, 2-phenoxyethanol, nonanoic acid, 8-heptadecene and eicosane were found in seropositive dogs for leishmaniasis. The guardian's posture has been increasingly important, requiring more attention to the dog's health and actions aimed at environmental management in an attempt to reduce cases of canine VL in the state. Even though the identified VOCs have not been associated with leishmanial infection, it is of great use for understanding canine hair substances.


Assuntos
Doenças do Cão , Leishmaniose Visceral , Animais , Cães , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Doenças do Cão/diagnóstico , Doenças do Cão/epidemiologia , Análise Espacial , Brasil , Ensaio de Imunoadsorção Enzimática
2.
Braz J Med Biol Res ; 56: e12947, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37851791

RESUMO

Chemotherapy is one of the most widely used treatments for breast cancer (BC). However, there is evidence of side effects like cognitive changes related to the chemotherapy treatment. The aim of the study was not only to summarize the existing evidence on the relationship between chemotherapy and cognitive performance in women with BC but also to identify additional consequences and aspects associated with these impairments. We conducted a systematic review with meta-analysis and meta-regression to present updated information on the matter. We retrieved data from the databases PubMed, Web of Science, PsycINFO, CINAHL, and Scopus. Twenty studies comprising over 2,500 women were examined and the results indicated that chemotherapy can compromise cognition in women with BC (-1.10 OR [95%CI: -1.81 to -0.74], P<0.01), with working memory (-0.49 OR [95%CI: -0.85 to -0.13], P=0.03) being the most affected among the domains. Furthermore, additional data indicated that cognitive impairment is most likely amid women with BC having a lower education level (Q=4.85, P=0.02). Our results suggested that chemotherapy affects cognitive functions in women with BC, and certain characteristics can worsen the deterioration. A comprehensive study of women with breast cancer and existing predictors contributes to optimized personal journeys, elevated life prospects, and advanced care that can also aid prognosis and therapeutic approaches.


Assuntos
Neoplasias da Mama , Disfunção Cognitiva , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Disfunção Cognitiva/induzido quimicamente , Cognição
3.
Braz. j. med. biol. res ; 56: e12947, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1513878

RESUMO

Chemotherapy is one of the most widely used treatments for breast cancer (BC). However, there is evidence of side effects like cognitive changes related to the chemotherapy treatment. The aim of the study was not only to summarize the existing evidence on the relationship between chemotherapy and cognitive performance in women with BC but also to identify additional consequences and aspects associated with these impairments. We conducted a systematic review with meta-analysis and meta-regression to present updated information on the matter. We retrieved data from the databases PubMed, Web of Science, PsycINFO, CINAHL, and Scopus. Twenty studies comprising over 2,500 women were examined and the results indicated that chemotherapy can compromise cognition in women with BC (-1.10 OR [95%CI: -1.81 to -0.74], P<0.01), with working memory (-0.49 OR [95%CI: -0.85 to -0.13], P=0.03) being the most affected among the domains. Furthermore, additional data indicated that cognitive impairment is most likely amid women with BC having a lower education level (Q=4.85, P=0.02). Our results suggested that chemotherapy affects cognitive functions in women with BC, and certain characteristics can worsen the deterioration. A comprehensive study of women with breast cancer and existing predictors contributes to optimized personal journeys, elevated life prospects, and advanced care that can also aid prognosis and therapeutic approaches.

5.
Res Vet Sci ; 138: 39-48, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34091228

RESUMO

Methotrexate (MTX), an antifolate drug, is widely used in chemotherapeutic protocols for metastatic and primary brain tumors and some autoimmune diseases. Its efficacy for brain tumors is limited by the high incidence of central nervous system (CNS) complications. This investigation aimed to observe the morphological effects, including astroglial and microglial responses, following systemic short-term MTX administration in adult rats. Male Wistar rats received 5 or 10 mg/kg/day of MTX by intraperitoneal route for 4 consecutive days (respectively, MTX5 and MTX10 groups) or the same volume of 0.9% saline solution (control group). On the 5th day, brain samples were collected for hematoxylin-eosin and luxol fast blue staining techniques, as well as for immunohistochemical staining for glial fibrillary acidic protein (GFAP) expression in astrocytes and Iba1 (ionized calcium binding adaptor molecule 1) for microglia in the frontal cortex, hippocampus, hypothalamus and molecular/granular layers of the cerebellum. Morphometric analyses were performed using Image Pro-Plus software. Brain levels of the proinflammatory cytokines TNF-α and IL-1ß were determined by ELISA. No signs of neuronal loss or demyelination were observed in all groups. Increased GFAP and Iba1 expression was found in all areas from the MTX groups, although it was slightly higher in the MTX10 group compared to the MTX5. Both TNF-α and IL-1ß levels were decreased in the MTX5 group compared to controls. In the MTX10 group, TNF-α decreased, although IL-1ß was increased relative to controls. MTX administration induced microglial reaction and astrogliosis in several CNS areas. In the MTX5 group, it apparently occurred in the presence of decreased proinflammatory cytokines.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Astrócitos/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/fisiopatologia , Metotrexato/administração & dosagem , Proteínas dos Microfilamentos/metabolismo , Microglia/efeitos dos fármacos , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Relação Dose-Resposta a Droga , Gliose/induzido quimicamente , Gliose/patologia , Masculino , Microglia/metabolismo , Microglia/patologia , Ratos , Ratos Wistar
6.
J Opt Soc Am A Opt Image Sci Vis ; 37(4): A70-A80, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32400518

RESUMO

This study evaluated reproducibility of the Trivector subtest of the Cambridge Colour Test. Data for normal trichromats were obtained in Brazil ($ N = 111 $N=111) at T0, six months (T1), and 12 months later (T2), and in the United Kingdom (${ N}={79}$N=79), with the test directly followed by a retest. Coefficients of repeatability-Bland-Altman indices-for Protan, Deutan, and Tritan vectors were similar for both datasets. Intraclass correlation coefficients (ICCs)-measures of reliability-were low or moderate for these relatively homogeneous datasets; for a heterogeneous dataset, comprising color-normal and abnormal observers, ICCs were 0.80-0.98, indicating the high discriminative accuracy of the Trivector subtest.

7.
Neotrop Entomol ; 48(6): 919-926, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31701476

RESUMO

Sugarcane is one of the most economically important crops in Brazil. The damage caused by Diatraea saccharalis (F.) (Lepidoptera: Crambidae) results in high costs for its production. Cotesia flavipes Cameron (Hymenoptera: Braconidae) is the most efficient means of controlling this pest. The prohibition of burning and the preservation of soil cover through non-tillage practices increased many population densities of natural enemies of the sugarcane borer (SCB) in sugarcane fields. Euborellia annulipes (Lucas) (Dermaptera: Anisolabididae) is a predator found in sugarcane fields and is associated with predation of SCB. This study aimed to evaluate the influence of parasitism of D. saccharalis by C. flavipes on predation by E. annulipes adult females. For this purpose, fourth instar sugarcane borer larvae were exposed to parasitism over a 5-day period or were not parasitized. Subsequently, the prey was supplied to the predator in arenas under choice and no-choice conditions and under different densities to evaluate the feeding preference over a 12-h period and functional response of the predator over a 24-h period. E. annulipes killed 2-3 fourth instar larvae of the sugarcane borer over a 12-h period. SCB parasitism did not affect the feeding preference of the predator and did not alter the type II functional response. However, the handling time of the predator was lower (1.943 h) and there was a higher T/Th ratio on the non-parasitized larvae (12.352). Our findings indicate E. annulipes as a promising biological control agent of D. saccharalis, with a potential to assist in the sugarcane borer management approaches and could to reduce the costs of parasitoid release in the field.


Assuntos
Himenópteros/fisiologia , Mariposas/parasitologia , Controle Biológico de Vetores , Saccharum , Animais , Brasil , Feminino , Larva/parasitologia
8.
Braz J Med Biol Res ; 51(3): e6568, 2018 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-29340521

RESUMO

The goal of this study was to compare the visual contrast sensitivity (CS) of men and women exposed and not exposed to organic solvents. Forty-six volunteers of both genders aged between 18 and 41 years (mean±SD=27.72±6.28) participated. Gas station attendants were exposed to gas containing 46.30 ppm of solvents at a temperature of 304±274.39 K, humidity of 62.25±7.59% and ventilation of 0.69±0.46 m/s (a passive gas chromatography-based sampling method was used considering the microclimate variables). Visual CS was measured via the psychophysical method of two-alternative forced choice using vertical sinusoidal gratings with spatial frequencies of 0.2, 0.5, 1.0, 2.0, 5.0, 10.0, and 16.0 cpd (cycles per degree) and an average luminance of 34.4 cd/m2. The results showed that visual CS was significantly lower (P<0.05) in the following groups: i) exposed men compared to unexposed men at frequencies of 0.2, 0.5, 1.0, and 2.0 cpd; ii) exposed women compared to unexposed women at a frequency of 5.0 cpd; and iii) exposed women compared to exposed men at a frequency of 0.5 cpd, even at exposures below the tolerance limit (300 ppm). These results suggest that the visual CS of exposed men was impaired over a wider range of spatial frequencies than that of exposed women. This difference may have been due to the higher body fat content of women compared to that of men, suggesting that body fat in women can serve as a protective factor against neurotoxic effects.


Assuntos
Sensibilidades de Contraste/efeitos dos fármacos , Exposição Ocupacional/efeitos adversos , Solventes/efeitos adversos , Percepção Visual/fisiologia , Tecido Adiposo/anatomia & histologia , Adolescente , Adulto , Brasil/epidemiologia , Escolaridade , Feminino , Humanos , Masculino , Microclima , Exposição Ocupacional/estatística & dados numéricos , Limiar Sensorial/fisiologia , Fatores Sexuais , Aprendizagem Espacial/fisiologia , Adulto Jovem
9.
Bull Entomol Res ; 108(4): 479-486, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29061199

RESUMO

We tested the sulfur-modulated plant resistance hypothesis using potted cabbage (Brassica oleracea var. capitata) plants that were grown without and with increasing levels of sulfur fertilization. Changes in plant chemical traits were assessed and developmental performance of Plutella xylostella, a highly host-specific leaf-chewing insect, was followed. Leaf sulfur concentration gradually increased with growing addition of sulfur in soil; however, there was a generalized saturation response curve, with a plateau phase, for improvements in total leaf nitrogen, defense glucosinolates and insect performance. Plutella xylostella performed better in sulfur-fertilized cabbage probably because of the higher level of nitrogen, despite of the higher content of glucosinolates, which are toxic for many non-specialized insects. Despite the importance of sulfur in plant nutrition and production, especially for Brassica crops, our results showed that sulfur fertilization could decrease plant resistance against insects with high feeding specialization.


Assuntos
Brassica/parasitologia , Fertilizantes , Mariposas , Nitrogênio/metabolismo , Enxofre/farmacologia , Animais , Brassica/química , Brassica/efeitos dos fármacos , Brassica/metabolismo , Herbivoria/efeitos dos fármacos , Mariposas/fisiologia , Nitrogênio/análise
10.
Chem Biol Interact ; 235: 10-6, 2015 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-25868679

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disorder; however, there is no treatment able to prevent the loss of dopaminergic neurons or its consequences. Trophic factors such as NGF and BDNF has positive effects on different disorders of the brain, including neurodegeneration. Additionally, studies have suggested the use of venom peptides as a therapeutic strategy for neurological disorders. Therefore, in the present study, we investigated the neuroprotective activity of a peptide isolated from Bothrops atrox venom and its trophic ability by using a cellular model of dopaminergic neurotoxicity induced by 1-methyl-4-phenylpyridinium (MPP(+)) in PC12 cells. We showed that it decreased the activities of the apoptotic proteases caspase-9 (mitochondrial) and caspase-3 (executor) and increased cell viability and proliferation in this model. Additionally, it increased neuritogenesis in non-treated PC12 cells (neuronal model) as well as in PC12 cells treated with the dopaminergic neurotoxin. The amino acid sequence of the peptide was identified as Glutamic acid-Valine-Tryptophan (Glu-Val-Trp). These findings suggest that this tripeptide has the potential to protect against the dopaminergic neurons loss and that trophic stimulation of neuroplasticity might be involved in its mechanism of neuroprotection.


Assuntos
Bothrops/metabolismo , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/tratamento farmacológico , Peptídeos/farmacologia , Peçonhas/farmacologia , 1-Metil-4-fenilpiridínio/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Ácido Glutâmico/farmacologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Biológicos , Células PC12 , Doença de Parkinson/metabolismo , Ratos , Triptofano/farmacologia , Valina/farmacologia
11.
Braz. j. med. biol. res ; 47(4): 321-327, 8/4/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-705767

RESUMO

The aim of this study was to assess contrast sensitivity for angular frequency stimuli as well as for sine-wave gratings in adults under the effect of acute ingestion of alcohol. We measured the contrast sensitivity function (CSF) for gratings of 0.25, 1.25, 2.5, 4, 10, and 20 cycles per degree of visual angle (cpd) as well as for angular frequency stimuli of 1, 2, 4, 24, 48, and 96 cycles/360°. Twenty adults free of ocular diseases, with normal or corrected-to-normal visual acuity, and no history of alcoholism were enrolled in two experimental groups: 1) no alcohol intake (control group) and 2) alcohol ingestion (experimental group). The average concentration of alcohol in the experimental group was set to about 0.08%. We used a paradigm involving a forced-choice method. Maximum sensitivity to contrast for sine-wave gratings in the two groups occurred at 4 cpd sine-wave gratings and at 24 and 48 cycles/360° for angular frequency stimuli. Significant changes in contrast sensitivity were observed after alcohol intake compared with the control condition at spatial frequency of 4 cpd and 1, 24, and 48 cycles/360° for angular frequency stimuli. Alcohol intake seems to affect the processing of sine-wave gratings at maximum sensitivity and at the low and high frequency ends for angular frequency stimuli, both under photopic luminance conditions.


Assuntos
Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Consumo de Bebidas Alcoólicas/fisiopatologia , Consumo de Bebidas Alcoólicas/psicologia , Sensibilidades de Contraste/efeitos dos fármacos , Análise de Fourier , Visão de Cores/efeitos dos fármacos , Etanol/análise , Psicofísica/métodos , Literatura de Revisão como Assunto , Percepção de Tamanho , Análise e Desempenho de Tarefas , Acuidade Visual , Percepção Visual/efeitos dos fármacos
12.
Braz J Med Biol Res ; 47(4): 321-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24676473

RESUMO

The aim of this study was to assess contrast sensitivity for angular frequency stimuli as well as for sine-wave gratings in adults under the effect of acute ingestion of alcohol. We measured the contrast sensitivity function (CSF) for gratings of 0.25, 1.25, 2.5, 4, 10, and 20 cycles per degree of visual angle (cpd) as well as for angular frequency stimuli of 1, 2, 4, 24, 48, and 96 cycles/360°. Twenty adults free of ocular diseases, with normal or corrected-to-normal visual acuity, and no history of alcoholism were enrolled in two experimental groups: 1) no alcohol intake (control group) and 2) alcohol ingestion (experimental group). The average concentration of alcohol in the experimental group was set to about 0.08%. We used a paradigm involving a forced-choice method. Maximum sensitivity to contrast for sine-wave gratings in the two groups occurred at 4 cpd sine-wave gratings and at 24 and 48 cycles/360° for angular frequency stimuli. Significant changes in contrast sensitivity were observed after alcohol intake compared with the control condition at spatial frequency of 4 cpd and 1, 24, and 48 cycles/360° for angular frequency stimuli. Alcohol intake seems to affect the processing of sine-wave gratings at maximum sensitivity and at the low and high frequency ends for angular frequency stimuli, both under photopic luminance conditions.


Assuntos
Consumo de Bebidas Alcoólicas/fisiopatologia , Consumo de Bebidas Alcoólicas/psicologia , Sensibilidades de Contraste/efeitos dos fármacos , Análise de Fourier , Adulto , Visão de Cores/efeitos dos fármacos , Etanol/análise , Feminino , Humanos , Masculino , Psicofísica/métodos , Literatura de Revisão como Assunto , Percepção de Tamanho , Análise e Desempenho de Tarefas , Acuidade Visual , Percepção Visual/efeitos dos fármacos , Adulto Jovem
13.
Braz J Med Biol Res ; 46(10): 855-60, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24141613

RESUMO

Changes in visual function beyond high-contrast acuity are known to take place during normal aging. We determined whether sensitivity to linear sine-wave gratings and to an elementary stimulus preferentially processed in extrastriate areas could be distinctively affected by aging. We measured spatial contrast sensitivity twice for concentric polar (Bessel) and vertical linear gratings of 0.6, 2.5, 5, and 20 cycles per degree (cpd) in two age groups (20-30 and 60-70 years). All participants were free of identifiable ocular disease and had normal or corrected-to-normal visual acuity. Participants were more sensitive to Cartesian than to polar gratings in all frequencies tested, and the younger adult group was more sensitive to all stimuli tested. Significant differences between sensitivities of the two groups were found for linear (only 20 cpd; P<0.01) and polar gratings (all frequencies tested; P<0.01). The young adult group was significantly more sensitive to linear than to circular gratings in the 20 cpd frequency. The older adult group was significantly more sensitive to linear than to circular gratings in all spatial frequencies, except in the 20 cpd frequency. The results suggest that sensitivity to the two kinds of stimuli is affected differently by aging. We suggest that neural changes in the aging brain are important determinants of this difference and discuss the results according to current models of human aging.


Assuntos
Envelhecimento/fisiologia , Sensibilidades de Contraste/fisiologia , Estimulação Luminosa/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Visual de Modelos/fisiologia , Acuidade Visual/fisiologia , Adulto Jovem
14.
Braz. j. med. biol. res ; 46(10): 855-860, 24/set. 2013. graf
Artigo em Inglês | LILACS | ID: lil-688555

RESUMO

Changes in visual function beyond high-contrast acuity are known to take place during normal aging. We determined whether sensitivity to linear sine-wave gratings and to an elementary stimulus preferentially processed in extrastriate areas could be distinctively affected by aging. We measured spatial contrast sensitivity twice for concentric polar (Bessel) and vertical linear gratings of 0.6, 2.5, 5, and 20 cycles per degree (cpd) in two age groups (20-30 and 60-70 years). All participants were free of identifiable ocular disease and had normal or corrected-to-normal visual acuity. Participants were more sensitive to Cartesian than to polar gratings in all frequencies tested, and the younger adult group was more sensitive to all stimuli tested. Significant differences between sensitivities of the two groups were found for linear (only 20 cpd; P<0.01) and polar gratings (all frequencies tested; P<0.01). The young adult group was significantly more sensitive to linear than to circular gratings in the 20 cpd frequency. The older adult group was significantly more sensitive to linear than to circular gratings in all spatial frequencies, except in the 20 cpd frequency. The results suggest that sensitivity to the two kinds of stimuli is affected differently by aging. We suggest that neural changes in the aging brain are important determinants of this difference and discuss the results according to current models of human aging.


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Envelhecimento/fisiologia , Sensibilidades de Contraste/fisiologia , Estimulação Luminosa/métodos , Reconhecimento Visual de Modelos/fisiologia , Acuidade Visual/fisiologia
15.
Neuroscience ; 233: 86-94, 2013 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-23291456

RESUMO

Caffeic acid phenethyl ester (CAPE) is a botanical compound abundant in honeybees' propolis. It has anti-inflammatory, antiviral, antioxidant, immunomodulatory and antitumor properties. Its beneficial effects against neurodegenerative diseases, including Parkinson's disease, have also been suggested and some mechanisms have been proposed. Mitochondrial damage and oxidative stress are critical events in neurodegeneration. Release of cytochrome c from mitochondria to cytosol and the downstream activation of caspase-3 have been suggested as targets of the protective mechanism of CAPE. Most of the studies addressing the protective effect of CAPE have been performed in cell culture. This is the first study to demonstrate the protective effect of CAPE against the dopaminergic neuronal loss induced by 6-hydroxydopamine (6-OHDA) in rats. It also demonstrates, for the first time, the inhibitory effect of CAPE on mitochondrial permeability transition (MPT), a mediator of neuronal death that triggers cytochrome c release and caspase-3 activation. Scavenging of reactive oxygen species (ROS) and metal chelation was demonstrated in the brain-affected areas of the rats treated with 6-OHDA and CAPE. Additionally, we demonstrated that CAPE does not affect brain mitochondrial function. Based on these findings and on its ability to cross the blood-brain barrier, CAPE is a promising compound to treat Parkinson's and other neurodegenerative diseases.


Assuntos
Ácidos Cafeicos/farmacologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Proteínas de Transporte da Membrana Mitocondrial/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Transtornos Parkinsonianos/prevenção & controle , Álcool Feniletílico/análogos & derivados , Adrenérgicos , Animais , Antioxidantes/farmacologia , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Sequestradores de Radicais Livres/farmacologia , Poro de Transição de Permeabilidade Mitocondrial , Oxidopamina , Transtornos Parkinsonianos/induzido quimicamente , Álcool Feniletílico/farmacologia , Ratos , Ratos Wistar
16.
Neotrop Entomol ; 42(6): 545-51, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27193271

RESUMO

Seasonal variation in plant quality may be intense enough to generate predictable patterns in insect herbivore populations. In order to explain seasonal oscillations in neotropical populations of the diamondback moth Plutella xylostella (L.), we tested the following: (1) if nutritional quality of cabbage (Brassica oleraceae var. capitata), a primary host plant of diamondback moth, adversely affects the performance of this insect in late spring and early summer, when populations decline and go extinct, and (2) if nutritional features of cabbage change with the seasons. We measured the performance of diamondback moth reared on leaves of cabbages grown during the four seasons of the year. Summer plants proved to be worse for the survival of the immature stages and subsequent adult fecundity, but there were no significant differences between the remaining seasons. Our results support the hypothesis that short-lived plants, grown in different seasons of the year in the tropics, have different nutritional and defensive attributes. We analyzed nutritional quality of cabbage leaves from the four seasons, but only total lipids were reduced in summer plants. Neotropical populations of diamondback moth collapse before plant quality decay in the summer. If the diamondback moth is well adapted to the seasonal deterioration of the habitat, including the reduction in the quality of host plants, it is expected that emigration happens before the mortality increases and natality decreases during the summer.


Assuntos
Brassica , Mariposas , Folhas de Planta , Animais , Herbivoria , Larva , Dinâmica Populacional , Estações do Ano
17.
J Toxicol Environ Health A ; 75(16-17): 981-90, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22852848

RESUMO

Cisplatin is a highly effective chemotherapeutic drug; however, its use is limited by nephrotoxicity. Studies showed that the renal injury produced by cisplatin involves oxidative stress and cell death mediated by apoptosis and necrosis in proximal tubular cells. The use of antioxidants to decrease cisplatin-induced renal cell death was suggested as a potential therapeutic measure. In this study the possible protective effects of carvedilol, a beta blocker with antioxidant activity, was examined against cisplatin-induced apoptosis in HK-2 human kidney proximal tubular cells. The mitochondrial events involved in this protection were also investigated. Four groups were used: controls (C), cisplatin alone at 25 µM (CIS), cisplatin 25 µM plus carvedilol 50 µM (CV + CIS), and carvedilol alone 50 µM (CV). Cell viability, apoptosis, caspase-9, and caspase-3 were determined. Data demonstrated that carvedilol effectively increased cell viability and minimized caspase activation and apoptosis in HK-2 cells, indicating this may be a promising drug to reduce nephrotoxicity induced by cisplatin.


Assuntos
Apoptose/efeitos dos fármacos , Carbazóis/farmacologia , Cisplatino/toxicidade , Células Epiteliais/efeitos dos fármacos , Túbulos Renais/citologia , Propanolaminas/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Antineoplásicos/toxicidade , Carvedilol , Caspase 3/genética , Caspase 3/metabolismo , Caspase 9/genética , Caspase 9/metabolismo , Linhagem Celular , Células Epiteliais/citologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos
18.
Arq. Inst. Biol. (Online) ; 78(1): 109-113, jan-mar, 2011. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1396414

RESUMO

Objetivou-se com este estudo avaliar a composição e a qualidade físico-química do leite pasteurizado padronizado comercializado na Cidade de São Luis, MA, verificar se estavam dentro dos padrões estabelecidos pela Instrução Normativa nº 51 do Ministério da Agricultura, Pecuária e Abastecimento e observar a ocorrência de fraudes econômicas como adição de água, através da densidade e crioscopia. Foram coletadas 20 amostras de leite pasteurizado padronizado durante o mês de maio de 2009, no comércio local da cidade. Foram realizadas análises de acidez, densidade, índice crioscópico, EST, ESD, proteína, gordura, cinzas, prova de peroxidase e fosfatase alcalina. Das 20 amostras analisadas, verificou-se que a densidade variou de 1,020 a 1,027 g/mL; a acidez de 10 a 14ºD; a gordura de 2,5 a 3,8%; o EST de 8,6 a 11,36%; ESD 6,1 a 7,86%; crioscopia 0,414 a 0,505ºC; proteínas de 2,4 a 3,32% e cinzas de 0,49 a 0,95%, a % de água adicionada variou de 1,27 a 17,83%. Todas as amostras apresentaram fosfatase negativa e peroxidase positiva. Com relação aos resultados obtidos, pode-se concluir que se apresentaram de forma geral insatisfatórios, evidenciando, principalmente, fraude do produto. Portanto, torna-se necessária a adoção de medidas de fiscalização por parte das autoridades competentes e maior conscientização das indústrias e consumidores.


The objective of this study to evaluate the composition and physico-chemical quality of standardized pasteurized milk marketed in São Luis, MA, Brazil, verify whether it was within the standards established by Instruction No. 51 of the Ministry of Agriculture, Livestock and Supply, and observe the occurrence of any economic fraud such as adding water, by measuring the density and freezing point. We collected 20 samples of standardized pasteurized milk during the month of May 2009, at a local town market. These were analyzed for acidity, density, cryoscopy, TS, SNF, protein, fat, ash, proof of peroxidase and alkaline phosphatase. Of the 20 samples analyzed, it was found that the density ranged from 1.020 to 1.027 g/mL; acidity from 10 to 14°D; fat from 2.5 to 3.8%; TS 8.6 to 11.36%; SNF 6.1 to 7.86%; freezing point 0.414 to 0.505°C; proteins from 2.4 to 3.32%; ash 0.49 to 0.95%; while the percentage of water added ranged from 1.27 to 17.83%. All samples were phosphatase negative and peroxidase positive. Regarding the results obtained, we can conclude that they were generally poor, showing mainly product fraud. Therefore, it is necessary to adopt measures for control by the relevant authorities and to raise awareness within the industries and among consumers.


Assuntos
Contaminação de Alimentos/análise , Leite/microbiologia , Composição de Alimentos/química , Pasteurização , Fraude
19.
Chem Biol Interact ; 189(1-2): 45-51, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21044617

RESUMO

Cisplatin is a highly effective chemotherapeutic agent which causes severe nephrotoxicity. Studies have suggested that reactive oxygen species, mainly generated in mitochondria, play a central role in cisplatin-induced renal damage. A wide range of antioxidants have been evaluated as possible protective agents against cisplatin-induced nephrotoxicity; however a safe and efficacious compound has not yet been found. The present study is the first to evaluate the protective potential of carvedilol, a beta-blocker with strong antioxidant properties, against the mitochondrial oxidative stress and apoptosis in kidney of rats treated with cisplatin. The following cisplatin-induced toxic effects were prevented by carvedilol: increased plasmatic levels of creatinine and blood urea nitrogen (BUN); lipid peroxidation, oxidation of cardiolipin; oxidation of protein sulfhydryls; depletion of the non-enzymatic antioxidant defense and increased activity of caspase-3. Carvedilol per se did not present any effect on renal mitochondria. It was concluded that carvedilol prevents mitochondrial dysfunction and renal cell death through the protection against the oxidative stress and redox state unbalance induced by cisplatin. The association of carvedilol to cisplatin chemotherapy was suggested as a possible strategy to minimize the nephrotoxicity induced by this antitumor agent.


Assuntos
Carbazóis/farmacologia , Cisplatino/toxicidade , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Propanolaminas/farmacologia , Animais , Antineoplásicos/toxicidade , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Nitrogênio da Ureia Sanguínea , Carvedilol , Creatinina/sangue , Interações Medicamentosas , Humanos , Malondialdeído/metabolismo , Mitocôndrias/metabolismo , Oxirredução , Ratos , Ratos Wistar , Estatísticas não Paramétricas
20.
Toxicon ; 56(1): 86-92, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20338188

RESUMO

The neurodegenerative diseases are important causes of morbidity and mortality in Western countries. Common mechanisms of toxicity involving mitochondrial damage have been suggested; however, a definitive treatment has not yet been found. Therefore, there has been great interest in the development of mitochondria-targeted protective compounds for the treatment of neuropathies. Animal toxins represent a promising source of new molecules with neuroprotective activity and potential to originate new drugs. We present here the effects of a low-molecular-mass peptides fraction (Ba-V) from Bothrops atrox snake venom, on rat brain mitochondrial function. Ba-V did not induce the mitochondrial swelling and moreover, was as effective as cyclosporin A (CsA) to inhibit the calcium/phosphate-induced swelling, which indicates its potential to prevent the mitochondrial permeability transition (MPT). The membrane electrochemical potential, the oxygen consumption during states-3 and -4 respirations as well as the respiratory control ratio (RCR) were not affected by Ba-V. Additionally, Ba-V did not induce reactive oxygen species (ROS) generation. Interestingly, Ba-V did not protect against the generation of ROS induced by t-BOH, which suggests a protection mechanism other than ROS scavenging. Given the important role of the mitochondrial damage and, more specifically, of MPT, in the development of neuropathies, Ba-V might be useful in the future strategies for the treatment of these diseases.


Assuntos
Bothrops , Venenos de Crotalídeos/química , Dilatação Mitocondrial/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Peptídeos/uso terapêutico , Proteínas de Répteis/uso terapêutico , Animais , Encéfalo , Brasil , Avaliação Pré-Clínica de Medicamentos , Peróxido de Hidrogênio/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Peso Molecular , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/efeitos adversos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/isolamento & purificação , Fosforilação Oxidativa/efeitos dos fármacos , Peptídeos/efeitos adversos , Peptídeos/química , Peptídeos/isolamento & purificação , Permeabilidade/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Proteínas de Répteis/efeitos adversos , Proteínas de Répteis/química , Proteínas de Répteis/isolamento & purificação
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