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1.
J Econ Entomol ; 113(4): 1804-1809, 2020 08 13.
Article in English | MEDLINE | ID: mdl-32484510

ABSTRACT

Integrated control tactics are often necessary for pest management. This is especially true for organisms such as the two-spotted spider mite, Tetranychus urticae Koch. The management of this mite pest species relies on pesticide use, but its short life cycle associated with high selection pressure results in frequent problems of acaricide resistance and population outbreaks. Therefore, combining acaricides and natural enemies is an appealing strategy for managing this pest species. The predatory mite Neoseiulus idaeus Denmark & Muma (Phytoseiidae) is important in arid environments, where other natural enemies show low efficacy. Thus, we investigated the effects of representative acaricides used for managing spider mites around the world in several crops (i.e., abamectin, fenpyroximate, and azadirachtin), on the functional and numerical responses of the phytoseid predator N. idaeus to increasing egg densities of its prey. Acaricide exposure did not affect the type of N. idaeus functional response or attack rate (a). However, acaricide exposure decreased the amount of consumed prey and increased prey handling time (Th). All acaricides affected the numerical response of the predator, which reduced oviposition rates. Therefore, caution is required in attempts to integrate the control methods.


Subject(s)
Acaricides , Mites , Tetranychidae , Animals , Female , Oviposition , Pest Control, Biological , Predatory Behavior
3.
Nature ; 569(7755): 215-221, 2019 05.
Article in English | MEDLINE | ID: mdl-31068722

ABSTRACT

Free-flowing rivers (FFRs) support diverse, complex and dynamic ecosystems globally, providing important societal and economic services. Infrastructure development threatens the ecosystem processes, biodiversity and services that these rivers support. Here we assess the connectivity status of 12 million kilometres of rivers globally and identify those that remain free-flowing in their entire length. Only 37 per cent of rivers longer than 1,000 kilometres remain free-flowing over their entire length and 23 per cent flow uninterrupted to the ocean. Very long FFRs are largely restricted to remote regions of the Arctic and of the Amazon and Congo basins. In densely populated areas only few very long rivers remain free-flowing, such as the Irrawaddy and Salween. Dams and reservoirs and their up- and downstream propagation of fragmentation and flow regulation are the leading contributors to the loss of river connectivity. By applying a new method to quantify riverine connectivity and map FFRs, we provide a foundation for concerted global and national strategies to maintain or restore them.


Subject(s)
Geographic Mapping , Rivers , Water Movements , Animals , Conservation of Natural Resources , Ecosystem , Fishes , International Cooperation , Reproducibility of Results
4.
Appl Radiat Isot ; 141: 241-245, 2018 Nov.
Article in English | MEDLINE | ID: mdl-29759888

ABSTRACT

Self-absorption correction factors are fundamental in spectroscopy to correct the efficiency of the samples detection whose density is different from the radioactive standard. Mathematical simulations have been widespread as a tool to facilitate the procedure of correction factors calculation. In this paper, LabSOCS was used to calculate the self-absorption correction factor for some geometries and the values found were compared to those obtained in MCNP and experimental values. The percentage deviations found for the self-absorption correction factor calculated by LabSOCS were below 1.6% when compared to experimental values. Deviations were below 1.9% in the curve extrapolation of the experimental procedure found in literature. Results obtained show that the deviations increase proportionally to the difference between the density values of the radioactive standard and the sample. High percentage deviations were also noticed in simulations whose samples had high densities, complex geometries and low energy gamma-rays.

5.
Radiat Prot Dosimetry ; 181(2): 149-155, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-29361110

ABSTRACT

Annual effective dose due to the consumption of 40K, 226Ra, 228Ra and 228Th was estimated from high-resolution gamma spectrometry, food consumption data for the inhabitants of Rio de Janeiro City and dose coefficients published by the ICRP 119. A total of 31 samples of cereals, grains, vegetables, flours, liquid and perishables were analyzed. 40K was measured in all samples, and bean sample presented highest specific concentration 489.36 ± 23.70 Bq kg-1. The highest specific concentration for 226Ra, 228Ra and 228Th was measured in pumpkin (7.82 ± 1.09 Bq kg-1), carrot (30.18 ± 1.99 Bq kg-1) and beet (2.43 ± 0.48 Bq kg-1), respectively. The highest contribution to annual effective dose came from beans (556.3 µSv), potato (12.5 µSv), carrot (10.3 µSv), banana (4.7 µSv) and beet (3.3 µSv). It was observed that updates of daily food consumption values was the main reason for an up to 10-fold difference between the annual effective dose found in the present study and literature data.


Subject(s)
Diet , Food Contamination, Radioactive/analysis , Potassium Radioisotopes/analysis , Radium/analysis , Thorium/analysis , Brazil , Humans , Radiation Dosage , Radiation Exposure , Radiation Monitoring
6.
Arq. bras. med. vet. zootec ; 66(1): 168-176, fev. 2014. ilus
Article in English | LILACS | ID: lil-704021

ABSTRACT

Chondrocytes obtained from stifle joint of New Zealand White rabbits were cultivated. Half of cells were maintained in culture for later implantation and the others frozen during six months to evaluate viability. A circular osteochondral defect was created in the right stifle of other twenty seven rabbits. The control group (CG) received no treatment. The thawed (TH) and fresh (FH) heterologous groups received, respectively, an implant of cultivated thawed or fresh heterologous chondrocytes associated with platelet rich plasma (PRP). The CG group showed greatest pain and lameness compared to the other groups seven days after the implantation. Microscopically, at 45 and 90 days, the TH and FH groups showed filling with cartilaginous tissue containing chondrocytes surrounded by a dense matrix of glycosaminoglycans. In the CG group, healing occurred with vascularized fibrous connective tissue without integration to the subchondral bone. Cryopreserved heterologous chondrocytes were viable for implantation and healing of osteochondral lesions; the association with PRP allows the fixation of cells in the lesion and offers growth factors which accelerates repair with tissue similar to articular hyaline cartilage.


Cultivaram-se condrócitos obtidos da articulação do joelho de coelhos. Metade das células foi mantida em cultura para posterior implantação, e a outra metade foi congelada durante seis meses com a finalidade de avaliar a viabilidade. Criou-se um defeito circular osteocondral no joelho direito de outros vinte e sete coelhos. O grupo controle (GC) não recebeu tratamento. Os grupos descongelado (TH) e fresco (FH) receberam, respectivamente, implantes heterólogos de condrócitos cultivados descongelados e frescos, associados com PRP. O grupo GC apresentou maior dor e claudicação em comparação com os outros grupos aos sete dias após o implante. Microscopicamente, aos 45 e 90 dias, os grupos TH e FH mostraram preenchimento da falha com tecido cartilaginoso contendo condrócitos circundados por uma matriz densa de glicosaminoglicanos. Nesse período, no grupo CG, a cura ocorreu com tecido conjuntivo fibroso vascularizado e sem integração com o osso subcondral. Condrócitos heterólogos criopreservados foram viáveis para implantação e tratamento de lesões osteocondrais; a associação com o PRP permitiu a fixação de células na lesão e ofereceu fatores de crescimento que aceleraram a reparação com o tecido semelhante à cartilagem hialina articular.


Subject(s)
Animals , Rabbits , Absorbable Implants , Chondrocytes/transplantation , Platelet-Rich Plasma/cytology , Rabbits
7.
Genet Mol Res ; 12(4): 5858-62, 2013 Nov 22.
Article in English | MEDLINE | ID: mdl-24301955

ABSTRACT

Myelodysplastic syndrome diagnosis of karyotypically normal patients may be elusive because it relies exclusively on morphological and clinical data. In routine practice, finding of an acquired mutation or a cytogenetic abnormality provides irrefutable evidence of the clonal nature of that disease. Recurrent deletions and somatic mutations in TET2, a gene involved in epigenetic regulation, have been reported in about 20% of adult patients with myelodysplastic syndrome. We report a novel g.95805C>T, nonsense TET2 mutation, leading to a premature stop codon (p.Gln913*), in an adult patient with refractory cytopenia with multilineage dysplasia.


Subject(s)
Codon, Nonsense , DNA-Binding Proteins/genetics , Myelodysplastic Syndromes/genetics , Proto-Oncogene Proteins/genetics , Aged , Dioxygenases , Female , Humans , Myelodysplastic Syndromes/diagnosis
8.
Arq. bras. med. vet. zootec ; 63(1): 46-55, Feb. 2011. ilus
Article in English | LILACS | ID: lil-582323

ABSTRACT

This work evaluated the effect of freezing on chondrocytes maintained in culture, aiming the establishment of a cell bank for future application as heterologous implant. Chondrocytes extracted from joint cartilage of nine healthy New Zealand White rabbits were cultivated and frozen with the cryoprotector 5 percent dimethylsulfoxide for six months. Phenotypic and scanning electron microscopy analyses were carried out to identify morphological and functional differences between fresh and thawed cells. After enzymatic digestion, a total of 4.8x10(5)cells per rabbit were obtained. Fresh chondrocytes showed a high mitotic rate and abundant matrix was present up to 60 days of culture. Loss of phenotypic stability was notable in the thawed chondrocytes, with a low labeling of proteoglycans and weak immunostaining of type II collagen. The present study showed important loss of chondrocyte viability under the freezing conditions. For future in vivo studies of heterologous implant, these results suggests that a high number of cells should be implanted in the host site in order to achieve an adequate number of viable cells. Furthermore, the chondrocytes should be implanted after two weeks of culture, when the highest viability rate is found.


Avaliaram-se os efeitos do congelamento sobre condrócitos mantidos em cultura, com o objetivo de se estabelecer um banco celular para futura aplicação como implante heterólogo. Condrócitos extraídos da cartilagem articular de nove coelhos saudáveis, da raça Nova Zelândia Branca, foram cultivados e submetidos ao congelamento, com o citoprotetor sulfóxido de dimetila a 5 por cento, por um período de seis meses. Análises fenotípicas e de microscopia eletrônica de varredura foram realizadas com o objetivo de identificar diferenças morfológicas e funcionais entre as células frescas e as descongeladas. Após a digestão enzimática, foram obtidas 4,8x10(5) células por coelho. Os condrócitos frescos apresentaram elevada taxa mitótica e abundante presença de matriz até os 60 dias de cultura. Nas culturas dos condrócitos descongelados, a perda de estabilidade fenotípica foi marcante, o que foi demonstrado pela baixa intensidade da coloração dos proteoglicanos e pela fraca imunomarcação do colágeno tipo II. Sob as condições de congelamento utilizadas, houve importante perda de viabilidade condrocítica. Para futuros estudos in vivo de implante heterólogo, estes resultados sugerem que o elevado número de células deve ser implantado no sítio hospedeiro, com o objetivo de se obter maior quantidade de células viáveis, e que os condrócitos deverão ser implantados com duas semanas de cultivo, período em que apresentam melhor taxa de viabilidade.


Subject(s)
Animals , Rabbits , Chondrocytes/cytology , Freezing , Microscopy, Electron, Scanning , Cell- and Tissue-Based Therapy
9.
Arq. bras. med. vet. zootec ; 59(1): 114-118, fev. 2007. ilus
Article in Portuguese | LILACS | ID: lil-456423

ABSTRACT

Avaliou-se o efeito da hidroxiapatita sintética na regeneração do osso alveolar e o efeito no tecido vivo de cães. Em dois grupos de 14 cães adultos hígidos, pesando entre 10 e 15kg, foram criados defeitos de 6 x 5mm na superfície vestibular do processo alveolar mandibular direito até atingir a raiz do quarto pré-molar. Em um grupo (tratado), o defeito foi preenchido com hidroxiapatita sintética; o grupo sem tratamento foi usado como controle. Efetuaram-se avaliações clínicas diárias durante uma semana, avaliações radiográficas após a cirurgia e aos oito, 21, 42, 60, 90 e 120 dias do pós-operatório. Vinte e quatro cães apresentaram inflamação, sendo a recuperação no grupo tratado mais lenta. Todos os animais tiveram sangramento com a hidroxiapatita. No grupo-controle houve aumento crescente da radiopacidade dos defeitos, no entanto, aos 120 dias do pós-operatório, os defeitos ainda eram visíveis. No grupo tratado, inicialmente a radiopacidade foi maior que a do osso normal, com diminuição gradual até se tornar semelhante à do osso vizinho, 60 dias após a cirurgia. A hidroxiapatita T290800-1 acelerou o preenchimento do defeito provocado no processo alveolar e acarretou inflamação e hemorragia gengival, o que, no entanto, não contra-indicou o seu uso.


The effect of the synthetic hydroxyapatite on the regeneration of the alveolar bone of dogs and on the alive tissue were evaluated. In two groups of 14 adult healthy dogs, weighing from 10 to 15kg, some defects around 6 x 5mm were provoked on the vestibular surface of the right jaw alveolar process until reaching the root of the forth premolar. In one group, the defect was infilled with synthetic hydroxyapatite. The no treated group dogs were used as control. Clinical evaluations were daily performed over one week, as well as radiographic evaluations after surgery, and on 8, 21, 42, 60, 90 and 120 days after surgery. Twenty-four dogs showed inflammation and the recovery in the treated group was slower than in the control group. Bleeding at the presence of hydroxyapatite was observed in all the animals. The radiographic examination presented an increasing radiopacity in the control group; however, this defect was still visible on day 120 after operation. Initially, in the treated group, radiopacity was higher than that of the normal bone and a gradual decrease occurred until becoming similar to the adjacent bone on day 60 days after surgery. The hydroxyapatite T290800-1 accelerated the infilling of the defect provoked in the alveolar process and caused gingival inflammation and hemorrhage; however, this does not contraindicate its use.


Subject(s)
Animals , Dogs , Durapatite/adverse effects , Mandibular Prosthesis Implantation/adverse effects , Mandibular Prosthesis Implantation/methods , Alveolar Process/transplantation , Transplantation, Autologous/adverse effects , Transplantation, Autologous/methods , Bone Regeneration , Radiography, Dental/methods
10.
Rev. ciênc. farm. básica apl ; 28(1): 51-56, 2007. tab
Article in Portuguese | LILACS | ID: lil-485201

ABSTRACT

O presente trabalho investigou os efeitos farmacológicos e toxicológicos do extrato metanólico dos galhos de Posoqueria acutifolia. Foram realizados os testes de contorções abdominais, formalina, placa quente, edema de pata e pleurisia, bem como para a toxicidade aguda. As doses de 100, 200 e 400 mg/kg inibiram as contorções abdominais. No teste da formalina, a dose de 400 mg/kg reduziu o tempo de lambida da primeira fase, enquanto este efeito foi observado nas doses de 200 e 400 mg/kg sobre a segunda fase. O tempo de permanência sobre aplaca quente aumentou na dose de 400 mg/kg, embora a dose de 200 mg/kg também tenha tido efeito significativo após 90 minutos de tratamento. Houve uma redução do edema de pata, do volume do exsudato e da migração leucocitária nas doses testadas. O extrato testado não foi tóxico nas doses avaliadas. Portanto, o extrato metanólicode P. acutifolia exibe efeitos analgésico e antiinflamatório, o que poderia estar relacionado a seu uso na medicina popular


In the present study, the pharmacological and toxic effects on mice of methanol extract of branches of the Brazilian tree Posoqueria acutifolia were investigated. The tests carried out were acetic acid induced writhing, paw licking induced by formalin, hot plate, paw edema and pleurisy, as well as in acute toxicity test. Doses of 100, 200 and 400 mg/kg inhibited the abdominal contortions. In the formalin test, the first phase of paw licking was shortened at the dose of 400 mg/kg, while the second phase was significantly affected by 200 and 400 mg/kg. The time of reaction to the hot plate increased with 400 mg/kg, although 200 mg/kg had a significant effect after 90 min of treatment. All doses of the methanolic extract reduced the paw edema, the volume of the exsudate and the leukocyte migration. The tested extract showed low acute toxicity to mice. It was concluded that (or thus) the methanol extract of P. acutifolia branches possess analgesic and antiinflammatory activity, which could justify the popular medicinal application of this plant.


Subject(s)
Animals , Male , Rats , Phytotherapy , Rubiaceae/toxicity , Plant Extracts/therapeutic use , Mice , Plant Preparations/pharmacology , Rats, Wistar
11.
Arq. bras. med. vet. zootec ; 58(5): 849-853, out. 2006. ilus
Article in Portuguese | LILACS | ID: lil-441533

ABSTRACT

Avaliou-se a hidroxiapatita sintética como substituto ósseo na regeneração do processo alveolar, utilizando-se 28 cães adultos hígidos, pesando entre 10 e 15kg, divididos em dois grupos. Foram criados defeitos de aproximadamente 6 x 5mm na superfície vestibular do processo alveolar até atingir a raiz do quarto pré-molar mandibular direito. Em um grupo, o defeito foi totalmente preenchido com hidroxiapatita sintética; o outro, sem tratamento, foi usado como controle. Aos 8, 15, 21, 42, 60, 90 e 120 dias, foram coletados fragmentos ósseos para a análise histológica sob microscopia óptica. Observou-se crescimento ósseo e vascular no interior dos poros de hidroxiapatita, intensa proliferação de osteoblastos e neovascularização na presença do implante. A biocompatibilidade da hidroxiapatita permitiu a sua integração com o processo alveolar por meio da formação direta de um osso lamelar. Ocorreu neoformação óssea à medida que a hidroxiapatita foi degradada.


The synthetic hydroxyapatite was evaluated as bone substitute in the regeneration of the alveolar process. Twenty-eight healthy adult dogs weighing from 10 to 15kg were divided into two groups. Defects around 6 x 5mm were provoked on the vestibular surface of the alveolar process until reaching the root of the fourth right mandibular premolar tooth. In one group the defect was totally infilled with synthetic hydroxyapatite, whereas the other untreated one was used as control. On days 8, 15, 21, 42, 60, 90 and 120, bone fragments were collected for the histological analysis under optical microscopy. The following results were observed: both bone and vascular growth inside the hydroxyapatite pores, intense osteoblast proliferations and neovascularization at the presence of the implant. The biocompatibility of the hydroxyapatite allowed its integration with the alveolar process by direct formation of a lamellar bone. The bone neoformation occurred as the hydroxyapatite was degraded.


Subject(s)
Animals , Dogs , Durapatite/analysis , Durapatite/therapeutic use , Mandible/surgery , Bone and Bones/anatomy & histology , Bone Regeneration/physiology
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