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1.
Plant Dis ; 105(1): 14-26, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32840434

RESUMO

Pathogen-tested foundation plant stocks are the cornerstone of sustainable specialty crop production. They provide the propagative units that are used to produce clean planting materials, which are essential as the first-line management option of diseases caused by graft-transmissible pathogens such as viruses, viroids, bacteria, and phytoplasmas. In the United States, efforts to produce, maintain, and distribute pathogen-tested propagative material of specialty crops are spearheaded by centers of the National Clean Plant Network (NCPN). Agricultural economists collaborated with plant pathologists, extension educators, specialty crop growers, and regulators to investigate the impacts of select diseases caused by graft-transmissible pathogens and to estimate the return on investments in NCPN centers. Economic studies have proven valuable to the NCPN in (i) incentivizing the use of clean planting material derived from pathogen-tested foundation plant stocks; (ii) documenting benefits of clean plant centers, which can outweigh operating costs by 10:1 to 150:1; (iii) aiding the development of disease management solutions that are not only ecologically driven but also profit maximizing; and (iv) disseminating integrated disease management recommendations that resonate with growers. Together, economic studies have reinforced efforts to safeguard specialty crops in the United States through the production and use of clean planting material.


Assuntos
Agricultura , Produtos Agrícolas , Estados Unidos
2.
Integr Org Biol ; 2(1): obaa021, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33791562

RESUMO

In ray-finned fishes, the sternohyoideus (SH) is among the largest muscles in the head region and, based on its size, can potentially contribute to the overall power required for suction feeding. However, the function of the SH varies interspecifically. In largemouth bass (Micropterus salmoides) and several clariid catfishes, the SH functions similarly to a stiff ligament. In these species, the SH remains isometric and transmitts power from the hypaxial musculature to the hyoid apparatus during suction feeding. Alternatively, the SH can shorten and contribute muscle power during suction feeding, a condition observed in the bluegill sunfish (Lepomis macrochirus) and one clariid catfish. An emerging hypothesis centers on SH muscle size as a predictor of function: in fishes with a large SH, the SH shortens during suction feeding, whereas in fish with a smaller SH, the muscle may remain isometric. Here, we studied striped surfperch (Embiotoca lateralis), a species in which the SH is relatively large at 8.8% of axial muscle mass compared with 4.0% for L. macrochirus and 1.7% for M. salmoides, to determine whether the SH shortens during suction feeding and is, therefore, bifunctional-both transmitting and generating power-or remains isometric and only transmits power. We measured skeletal kinematics of the neurocranium, urohyal, and cleithrum with Video Reconstruction of Moving Morphology, along with muscle strain and shortening velocity in the SH and epaxial muscles, using a new method of 3D external marker tracking. We found mean SH shortening during suction feeding strikes (n = 22 strikes from four individual E. lateralis) was 7.2 ± 0.55% (±SEM) of initial muscle length. Mean peak speed of shortening was 4.9 ± 0.65 lengths s-1, and maximum shortening speed occurred right around peak gape when peak power is generated in suction feeding. The cleithrum of E. lateralis retracts and depresses but the urohyal retracts and depresses even more, a strong indicator of a bifunctional SH capable of not only generating its own power but also transmitting hypaxial power to the hyoid. While power production in E. lateralis is still likely dominated by the axial musculature, since even the relatively large SH of E. lateralis is only 8.8% of axial muscle mass, the SH may contribute a meaningful amount of power given its continual shortening just prior to peak gape across all strikes. These results support the finding from other groups of fishes that a large SH muscle, relative to axial muscle mass, is likely to both generate and transmit power during suction feeding.

3.
J Insect Sci ; 15: 112, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26223949

RESUMO

Vineyards were surveyed for grapevine leafroll-associated viruses and their insect vectors in New York State's Finger Lakes region in 2006-2008. Grape mealybug, Pseudococcus maritimus (Erhorn) (Hemiptera: Pseudococcidae), European Fruit Lecanium, Parthenolecanium corni (Bouche), and Cottony Maple Scale, Pulvinaria acericola (Walsh and Riley) (Hemiptera: Coccidae) were identified as vector species in this region. An increase in the incidence of Grapevine leafroll-associated virus 1 (GLRaV-1) and GLRaV-3 was observed in 8 of the 20 vineyards surveyed, which implies transmission by these insect vectors. Two of the vineyards for which a temporal increase in disease incidence was documented were then used to evaluate the efficacy of foliar applications of horticultural oil and two classes of insecticides for control of P. maritimus and for slowing virus spread over 2 years of vine protection. Delayed dormant applications of horticultural oil contributed to control of early season crawlers; however, this was not the case for control of summer populations. Applications of acetamiprid and spirotetramat achieved control in summer populations; however, spirotetramat outperformed acetamiprid in percent reduction of treated compared with control vines and in a side-by-side trial. Vines treated with spirotetramat had a lower percentage of new vines testing positive for GLRaV-1 than control vines after 2 years, while no other spray program altered the increase in incidence of GLRaV-1 or -3.


Assuntos
Compostos Aza , Hemípteros , Insetos Vetores , Inseticidas , Compostos de Espiro , Vitis/virologia , Animais , Controle de Insetos , Neonicotinoides , New York , Piridinas , Distribuição Aleatória
4.
Phytopathology ; 99(10): 1177-84, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19740031

RESUMO

The occurrence and diversity of Grapevine leafroll-associated virus 1 (GLRaV-1) and Grapevine leafroll-associated virus 3 (GLRaV-3) in the soft scales Parthenolecanium corni and Pulvinaria innumerabilis and in the mealybug Pseudococcus maritimus was determined in leafroll-affected vineyards in the Finger Lakes region of New York. Groups of 1 to 4 specimens were collected under loose grapevine bark and tested by reverse-transcription polymerase chain reaction (RT-PCR) for segments of the second diverged copy of the GLRaV-1 coat protein gene or GLRaV-3 heat-shock protein 70-homologue gene. Virus-specific RT-PCR products were amplified from immature insect vectors and adult mealybugs. Single viral amplicons were obtained mostly from immature vectors (35%, 30 of 85) and dual viral amplicons from immature (16%, 10 of 61) and adult (100%, 14 of 14) mealybugs, including individuals. These observations suggested a simultaneous uptake of GLRaV-1 and GLRaV-3 by individual mealybugs. Furthermore, a comparative nucleotide sequence analysis of viral amplicons from soft scales, mealybugs, and grapevines from which vectors were collected showed identical or highly similar haplotypes, indicating that uptake of GLRaV-1 and GLRaV-3 likely occurred by direct feeding of vectors on their host plants.


Assuntos
Biodiversidade , Insetos Vetores/virologia , Insetos/virologia , Doenças das Plantas/virologia , Vírus de Plantas/fisiologia , Vitis/parasitologia , Vitis/virologia , Animais , DNA de Plantas/genética , New York , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Plant Dis ; 93(4): 395-401, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30764222

RESUMO

Vineyards in the Finger Lakes region in New York were surveyed for the three major viruses associated with leafroll disease, i.e., Grapevine leafroll-associated virus 1 (GLRaV-1), Grapevine leafroll-associated virus 2 (GLRaV-2), and Grapevine leafroll-associated virus 3 (GLRaV-3). Target viruses were detected in nearly two-thirds (68%, 65 of 95) of the vineyard blocks surveyed by enzyme-linked immunosorbent assay. Single infections by GLRaV-1, GLRaV-2, and GLRaV-3 occurred in 10% (113 of 1,124), 3% (36 of 1,124), and 15% (173 of 1,124) of the samples tested, respectively, whereas mixed infections affected 3.6% (40 of 1,124) of them, essentially with GLRaV-1 and GLRaV-3 (2.5%, 28 of 1,124). Presence of the target viruses was confirmed in selected samples by reverse transcription-polymerase chain reaction and sequencing. Comparative analysis indicated moderate to high nucleotide sequence identities in the second diverged copy of the GLRaV-1 coat protein gene (81.0 to 86.7%), GLRaV-2 coat protein gene (87.6 to 99.2%), and GLRaV-3 heat shock protein 70 homologue gene (91.5 to 98.3%) of New York isolates with corresponding virus reference strains. The prevalence of the three major leafroll disease-associated viruses in Finger Lakes vineyards results likely from poor sanitary status of planting materials, stressing the need to reinstate a certification program in New York.

6.
Vopr Onkol ; 49(4): 467-71, 2003.
Artigo em Russo | MEDLINE | ID: mdl-14569939

RESUMO

We used rat liver tissue slices and isolated hepatocytes to demonstrate that single exposures to a "weak" carcinogen 4-dimethylaminoazobenzol (DAB) or to a "strong" one, such as N-diethylnitrosamine (DENA), cause identical antigenic restructuring to occur. It presented as formation of membranous heteroorganic antigens of renal origin on hepatocyte surfaces. Antigens were associated with Zajdela's hepatoma; their synthesis lasted longer after exposure to DENA. They, however, were not identified in intact rat liver. Their synthesis, following single exposure, was assayed immunocytofluorimetrically. It is suggested that the antigens be used as markers of cell dysdifferentiation and malignancy and testing substances for carcinogenicity.


Assuntos
Antígenos de Neoplasias/análise , Biomarcadores Tumorais/análise , Hepatócitos/patologia , Neoplasias Hepáticas Experimentais/química , Neoplasias Hepáticas Experimentais/patologia , Fígado/patologia , Animais , Carcinógenos , Diferenciação Celular , Transformação Celular Neoplásica , Dietilnitrosamina , Fluorometria , Hepatócitos/química , Imuno-Histoquímica , Técnicas In Vitro , Fígado/química , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/imunologia , Ratos , p-Dimetilaminoazobenzeno
7.
Biochim Biophys Acta ; 1409(2): 72-86, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9838052

RESUMO

Two protocols were developed that yielded purified oxygen-evolving thylakoid membranes from the diatom Cylindrotheca fusiformis. One protocol employed sonication, while the second involved French press lysis of protoplasts formed by brief culture of cells in a cation-depleted medium. Regardless of the method of cell breakage, some damage to electron transport components occurred. For preservation of both light-dependent electron transport activity and in vivo fluorescence properties, 2 M sorbitol proved to be more effective than 1 M sorbitol, regardless of the method used for cell lysis. Thylakoids purified in 2 M sorbitol using the protoplast/French press method showed the best preservation of in vivo fluorescence emission signals and Photosystem II activity with ferricyanide was completely inhibited by DCMU. Thylakoids purified in 2 M sorbitol using sonication had higher rates of Photosystem II activity with ferricyanide, but this activity was less sensitive to DCMU. Whole-chain electron transport activity was low in all preparations. This is the first report of O2 evolution and of long-wavelength fluorescence in purified thylakoids of any chromophytic alga.


Assuntos
Diatomáceas/metabolismo , Oxigênio/análise , Microbiologia da Água , Diatomáceas/ultraestrutura , Transporte de Elétrons , Protoplastos/metabolismo
8.
Health Phys ; 71(6): 944-6, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8919078

RESUMO

The magnetic field and ionizing radiation dose rate were measured near ground level in the vicinity of a utility power line. The dose rate was monitored using thermoluminescence detectors. Measurements were made at distances up to about 100 m from the main transmission line from the Kewaunee Nuclear Power Plant while the plant was in operation and while the plant was shut down for refueling. No evidence was found that the dose rate is significantly different in the presence of the magnetic field from the power line than in its absence.


Assuntos
Campos Eletromagnéticos , Monitoramento de Radiação/métodos , Radiação Ionizante , Clima , Raios gama , Centrais Elétricas , Doses de Radiação , Wisconsin
9.
Am J Hum Genet ; 57(5): 1104-13, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7485161

RESUMO

Larsen syndrome (LS) is a skeletal dysplasia (osteochondrodysplasia) in which multiple dislocations of the large joints are the major feature. Nosology in this group of diseases, which constitutes 8% of Mendelian disorders in man, is primarily based on clinical and radiographic features. Hopes for more accurate classification grounds are currently being met by progress in elucidation of underlying genetic defects. We have performed linkage analysis in a large Swedish kindred with autosomal dominant LS and found the gene (LAR1) to be strongly linked to chromosome 3p markers (Zmax = 13.4 at (theta = .00). Recombination analysis indicates that the LAR1 locus is located in a region defined distally by D3S1581 and proximally by D3S1600, which cytogenetically maps to chromosome region 3p21.1-14.1. Linkage and recombination analysis of a COL7A1 PvuII intragenic polymorphism versus LS and chromosome 3 markers indicate that COL7A1 is located close to, but distinct from, the LAR1 locus.


Assuntos
Cromossomos Humanos Par 3 , Osteocondrodisplasias/genética , Mapeamento Cromossômico , Ligação Genética , Humanos , Recém-Nascido , Escore Lod , Linhagem , Polimorfismo Genético , Recombinação Genética , Síndrome
10.
Anal Biochem ; 228(1): 123-30, 1995 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-8572268

RESUMO

Photosynthetic pigments and acyl lipids were simultaneously extracted and concentrated by sec-butanol. Pigments extracted with sec-butanol were indistinguishable from those extracted using acetone as determined by quantitative and qualitative HPLC. Use of sec-butanol has several advantages over conventional extraction solvents: (1) pigments are extracted directly from polyacrylamide gel slices without an elution step; (2) pigments in dilute, isolated pigment-protein complexes are extracted and concentrated without first concentrating the sample; (3) when necessary, the concentration factor is readily increased by addition of water; (4) sec-butanol extracts acyl lipids and vitamin K1 as effectively, but much quicker, than chloroform:methanol; (5) sec-butanol rapidly extracts and concentrates pigments from thylakoids of all plant species tested and even directly from many algal/higher plant cells, facilitating analysis of pigment biosynthetic pathways using radioactive substrates; and (6) pigments are stable in sec-butanol for several days at room temperature in the dark or for many weeks if stored at -20 degrees C in darkness. Finally, sec-butanol is preferable to ether for concentrating pigments extracted with acetone.


Assuntos
Lipídeos/isolamento & purificação , Pigmentos Biológicos/isolamento & purificação , Butanóis , Cromatografia Líquida de Alta Pressão , Plantas/química
11.
Med Tr Prom Ekol ; (11): 37-40, 1995.
Artigo em Russo | MEDLINE | ID: mdl-8689076

RESUMO

Experimental study revealed noticeable desensibilization caused by the use of medicinal herbs collections in laboratory animals sensibilized by chromium and nickel. That desensibilization effect of herbal medications is believed to result from activation and normalization of processes removing the agents from the body. Revealed experimentally and supported by clinical trials, therapeutic efficiency of the medicinal herbs collections makes them applicable for treatment and prophylaxis of allergies associated with metals.


Assuntos
Alérgenos/efeitos adversos , Hipersensibilidade a Drogas/imunologia , Poluentes Ambientais/efeitos adversos , Metais/efeitos adversos , Fitoterapia , Animais , Criança , Pré-Escolar , Modelos Animais de Doenças , Avaliação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Lactente , Masculino , Camundongos , Extratos Vegetais/uso terapêutico
12.
Gig Tr Prof Zabol ; (12): 30-2, 1991.
Artigo em Russo | MEDLINE | ID: mdl-1817083

RESUMO

Studied were the new components of dielectric coatings: di-para-xylilene, di-bromine-di-para-xylilene, dichlor-di-para-xylilene, which manifested themselves as low-toxicity compounds free from irritating, sensitizing and fibrogenous effects. The acute action thresholds for aerosols of the paraxylilenes were established at 10 mg/m3 (with regard to general and embryotoxicity), at 5 mg/m3 for the maximal inactive concentrations.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Poluentes Atmosféricos/toxicidade , Compostos de Anilina/toxicidade , Aerossóis , Animais , Relação Dose-Resposta a Droga , Humanos , Concentração Máxima Permitida , Camundongos , Ratos , U.R.S.S.
13.
Lab Delo ; (5): 9-10, 1991.
Artigo em Russo | MEDLINE | ID: mdl-1715958

RESUMO

The suggested complex method for assessment of red blood cell and leukocyte counts and membranous function helps assess the time course of cellular membrane and peripheral blood status from the minimal volumes of the blood by precise estimation of cell loss using conductometry.


Assuntos
Contagem de Eritrócitos/instrumentação , Membrana Eritrocítica/fisiologia , Contagem de Leucócitos/instrumentação , Humanos
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