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The abundance of chlorine in the Earth's atmosphere increased considerably during the 1970s to 1990s, following large emissions of anthropogenic long-lived chlorine-containing source gases, notably the chlorofluorocarbons. The chemical inertness of chlorofluorocarbons allows their transport and mixing throughout the troposphere on a global scale, before they reach the stratosphere where they release chlorine atoms that cause ozone depletion. The large ozone loss over Antarctica was the key observation that stimulated the definition and signing in 1987 of the Montreal Protocol, an international treaty establishing a schedule to reduce the production of the major chlorine- and bromine-containing halocarbons. Owing to its implementation, the near-surface total chlorine concentration showed a maximum in 1993, followed by a decrease of half a per cent to one per cent per year, in line with expectations. Remote-sensing data have revealed a peak in stratospheric chlorine after 1996, then a decrease of close to one per cent per year, in agreement with the surface observations of the chlorine source gases and model calculations. Here we present ground-based and satellite data that show a recent and significant increase, at the 2σ level, in hydrogen chloride (HCl), the main stratospheric chlorine reservoir, starting around 2007 in the lower stratosphere of the Northern Hemisphere, in contrast with the ongoing monotonic decrease of near-surface source gases. Using model simulations, we attribute this trend anomaly to a slowdown in the Northern Hemisphere atmospheric circulation, occurring over several consecutive years, transporting more aged air to the lower stratosphere, and characterized by a larger relative conversion of source gases to HCl. This short-term dynamical variability will also affect other stratospheric tracers and needs to be accounted for when studying the evolution of the stratospheric ozone layer.
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BACKGROUND: Isochoric freezing systems enable ice-free preservation of biological matter at subfreezing temperatures under the increased hydrostatic pressure. OBJECTIVE: To examine the effects of pressure and exposure period on rat hearts preserved in an isochoric chamber. MATERIALS AND METHODS: Rat hearts were preserved in the UW solution in isochoric chambers at temperatures from -2°C to -8°C and pressure from the atmospheric level to 78 MPa for up to eight hours, with and without the addition of glycerol. Hearts were evaluated via Langendorff perfusion and HE histology. RESULTS: Hearts were compromised quickly as pressure increased, suggesting an acute time-pressure sensitivity. With the addition of 1 M glycerol, which reduces the pressure experienced at a given temperature, the survival time at -4°C was doubled. CONCLUSION: The enhanced hydrostatic pressure encountered during isochoric preservation yields time-dependent negative effects on the heart, which can potentially be alleviated by the addition of a cryoprotectant.
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Criopreservação/instrumentação , Coração , Isocoros , Soluções para Preservação de Órgãos , Preservação de Órgãos/instrumentação , Adenosina , Alopurinol , Animais , Glutationa , Pressão Hidrostática , Insulina , Rafinose , Ratos , TemperaturaRESUMO
Fallopia japonica (Houtt.) Ronse Decr. (= Polygonum cuspidatum Siebold & Zucc.; Japanese knotweed, JKW) is an invasive perennial forb in the Polygonaceae. It has been identified as a target for biological control in many parts of the world, including the United States. Several potted JKW plants in an outdoor study at the Oregon Department of Agriculture, Salem (44.93° N, 122.99° W) developed leaf spots. Samples collected on August 20, 2007, were sent to the FDWSRU for identification of the disease. The necrotic leaf spots were brown and large, 1 to 3 cm in diameter, and in some cases occupying 30% of the leaf area. Both hemispherical and discoid conidiomata with gloeoid spore masses (3) developed in necrotic areas of all leaves placed in moist chambers. Discoid conidiomata had dark, pedicellate bases subtending a fimbriate disc on which pale brown to brown gloeoid conidial masses were produced. Hemispherical conidiomata were black, circular, sessile, and somewhat flattened, within which similar, gloeoid conidial masses were produced. Conidia from each type of conidioma were unicellular, cylindrical to fusiform, hyaline, and 4.5 to 7.2 × 0.9 to 1.8 µm (mean 5.7 × 1.33). Artificial inoculation of 15 plants was made on two occasions with a suspension of 106 conidia per ml, followed by two 16-hr dew periods at 25°C that were separated by an 8-hr "day;" a similar set of 15 non-inoculated plants served as controls each time. Symptoms similar to those in the original sample developed within 2 months after inoculation. The fungus was easily reisolated, and conidia from each type of conidioma produced similar growth on artificial media and similar disease after inoculation. The characteristics of conidial size and distinctly different conidiomata are diagnostic of Pilidium concavum (Desm.) Höhn (3,4). A sequence of the ITS1-5.8S-ITS2 region DNA, extracted using a DNeasy Plant Mini Kit (QIAGEN), was found identical to that of P. concavum from Rosa sp. (BPI 1107275; GenBank Accession No. AY487094), using BLAST. This isolate, FDWSRU 07-116, has been deposited in the US National Fungus Collection (BPI 883546) and at the Centraalbureau voor Schimmelcultures (CBS 132725). Sequence data have been deposited in GenBank (JQ790789). To our knowledge, this is the first report of P. concavum causing disease on a member of the Polygonaceae in North America (1), a disease clearly different from a Japanese Mycosphaerella sp. under consideration for biological control of JKW in the United Kingdom (2). References: (1) D. F. Farr, and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , May 15, 2012. (2) D. Kurose et al. MycoSci. 50:179, 2009. (3) M. E. Palm, Mycologia 83:787, 1991. (4) A. Y. Rossman, et al. Mycol. Progr. 3:275, 2004.
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Soybean rust (SBR), caused by the fungus Phakopsora pachyrhizi, was detected on Florida Beggarweed (Desmodium tortuosum) for the first time in Alabama in November, 2009. The pathogen was not observed in 2010 or 2011, probably because of the exceptionally dry, hot weather in the region. The pathogen was observed on multiple mature leaves of plants, evenly distributed through a field at the Wiregrass Research and Extension Center in Headland, Alabama, located in the southeast region of the state. Florida Beggarweed can serve as an overwintering host for SBR. Symptoms on leaves were consistent with SBR symptoms previously described on soybeans (1). Sori in multiple pustules were observed on the undersurface of the leaves. Urediniospores and paraphyses were observed microscopically and identified as P. pachyrhizi. Symptomatic leaves from 20 plants were analyzed using an Envirologix monoclonal antibody strip test kit at the Auburn University Plant Diagnostic Laboratory. A subsample of 20 plants were positive for the pathogen. Representative symptomatic leaves were sent to the USDA Molecular Diagnostic Laboratory in Beltsville, Maryland, for confirmation. DNA was extracted from sori aseptically removed from leaves using a Qiagen DNeasy Plant Mini Kit, and amplified with primers Ppa1 and NL4. The resulting partial ITS2 and 28S ribosomal RNA sequences were 100% identical to GenBank entry DQ354537. Voucher specimens were deposited in the USDA Agricultural Research Service, National Fungus Collection (BPI). To our knowledge, this is the first report of the disease on Florida Beggarweed in Alabama. References: (1) A. Carcamo Rodriguez et al. Plant Dis. 90:1260, 2006. (2) R. D. Frederick et al. Phytopathology 92:217, 2002.
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In March 2010, citrus black spot symptoms were observed on sweet orange trees in a grove near Immokalee, FL. Symptoms observed on fruit included hard spot, cracked spot, and early virulent spot. Hard spot lesions were up to 5 mm, depressed with a chocolate margin and a necrotic, tan center, often with black pycnidia (140 to 200 µm) present. Cracked spot lesions were large (15 mm), dark brown, with diffuse margins and raised cracks. In some cases, hard spots formed in the center of lesions. Early virulent spot lesions were small (up to 7 mm long), bright red, irregular, indented, and often with many pycnidia. In addition, small (2 to 3 mm), elliptical, reddish brown leaf lesions with depressed tan centers were observed on some trees with symptomatic fruit. Chlorotic halos appeared as they aged. Most leaves had single lesions, occasionally up to four per leaf. Tissue pieces from hard spots and early virulent spots were placed aseptically on potato dextrose agar (PDA), oatmeal agar, or carrot agar and incubated with 12 h of light and dark at 24°C. Cultures that grew colonies within a week were discarded. Fourteen single-spore cultures were obtained from the isolates that grew slower than the Guignardia mangiferae reference cultures, although pycnidia formed more rapidly in the G. mangiferae cultures (1). No sexual structures were observed. Cultures on half-PDA were black and cordlike with irregular margins with numerous pycnidia, often bearing white cirrhi after 14 days. Conidia (7.1 to 7.8 × 10.3 to 11.8 µm) were hyaline, aseptate, multiguttulate, ovoid with a flattened base surrounded by a hyaline matrix (0.4 to 0.6 µm) and a hyaline appendage on the rounded apex, corresponding to published descriptions of G. citricarpa (anomorph Phyllosticta citricarpa) (1). A yellow pigment was seen in oatmeal agar surrounding G. citricarpa, but not G. mangiferae colonies as previously reported (1,2). DNA was extracted from lesions and cultures and amplified with species-specific primers (2). DNA was also extracted from G. mangiferae and healthy citrus fruit. The G. citricarpa-specific primers produced a 300-bp band from fruit lesions and pure cultures. G. mangiferae-specific primers produced 290-bp bands with DNA from G. mangiferae cultures. The internally transcribed spacer (ITS) of the rRNA gene, translation-elongation factor (TEF), and actin gene regions were sequenced from G. citricarpa isolates and deposited in GenBank. These sequences had 100% homology with G. citricarpa ITS sequences from South Africa and Brazil, 100% homology with TEF, and 99% homology with actin of a Brazilian isolate. Pathogenicity tests with G. citricarpa were not done because the organism infects immature fruit and has an incubation period of at least 6 months (3). In addition, quarantine restrictions limit work with the organism outside a contained facility. To our knowledge, this is the first report of black spot in North America. The initial infested area was ~57 km2. The disease is of great importance to the Florida citrus industry because it causes serious blemishes and significant yield reduction, especially on the most commonly grown 'Valencia' sweet orange. Also, the presence of the disease in Florida may affect market access because G. citricarpa is considered a quarantine pathogen by the United States and internationally. References: (1) R. P. Baayen et al. Phytopathology 92:464, 2002. (2) N. A. Peres et al. Plant Dis. 91:525, 2007 (3) R. F. Reis et al. Fitopath Bras. 31:29, 2006.
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The core species of the family Planistromellaceae are included in the teleomorphic genera Planistroma and Planistromella and the connected anamorphic, coelomycetous genera Alpakesa, Kellermania, and Piptarthron. These genera have been defined primarily on the basis of ascospore septation or number of conidial appendages. Due to a lack of DNA sequence data, phylogenetic placement of these genera within the Dothideomycetes, evaluation of monophyly, and questions about generic boundaries could not be adequately addressed in the past. Isolates of nearly all of the known species in these genera were studied genetically and morphologically. DNA sequence data were generated for the nSSU, ITS, nLSU, and RPB1 markers and analysed phylogenetically. These results placed the Planistromellaceae, herein recognised as a distinct family, in an unresolved position relative to other genera within the order Botryosphaeriales. Species representing the core genera of the Planistromellaceae formed a clade and evaluation of its topology revealed that previous morphology-based definitions of genera resulted in an artificial classification system. Alpakesa, Kellermania, Piptarthron, Planistroma, and Planistromella are herein recognised as belonging to the single genus Kellermania. The following new combinations are proposed: Kellermania crassispora, K. dasylirionis, K. macrospora, K. plurilocularis, and K. unilocularis. Five new species are described, namely K. con- fusa, K. dasylirionicola, K. micranthae, K. ramaleyae, and K. rostratae. Descriptions of species in vitro and a key to species known from culture are provided.
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Quantum sensors based on spin defects in diamond have recently enabled detailed imaging of nanoscale magnetic patterns, such as chiral spin textures, two-dimensional ferromagnets, or superconducting vortices, based on a measurement of the static magnetic stray field. Here, we demonstrate a gradiometry technique that significantly enhances the measurement sensitivity of such static fields, leading to new opportunities in the imaging of weakly magnetic systems. Our method relies on the mechanical oscillation of a single nitrogen-vacancy center at the tip of a scanning diamond probe, which up-converts the local spatial gradients into ac magnetic fields enabling the use of sensitive ac quantum protocols. We show that gradiometry provides important advantages over static field imaging: (i) an order-of-magnitude better sensitivity, (ii) a more localized and sharper image, and (iii) a strong suppression of field drifts. We demonstrate the capabilities of gradiometry by imaging the nanotesla fields appearing above topographic defects and atomic steps in an antiferromagnet, direct currents in a graphene device, and para- and diamagnetic metals.
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BACKGROUND: Generalized anxiety disorder (GAD) is under-researched despite its high prevalence and large impact on the healthcare system. There is a paucity of functional magnetic resonance imaging (fMRI) studies that explore the neural correlates of emotional processing in GAD. The present study investigated the blood oxygen level dependent (BOLD) response to processing positive and negative facial emotions in patients with GAD. METHOD: A total of 15 female GAD patients and 16 female controls undertook an implicit face emotion task during fMRI scanning. They also performed a face emotion recognition task outside the scanner. RESULTS: The only behavioural difference observed in GAD patients was less accurate detection of sad facial expressions compared with control participants. However, GAD patients showed an attenuated BOLD signal in the prefrontal cortex to fearful, sad, angry and happy facial expressions and an attenuated signal in the anterior cingulate cortex to happy and fearful facial expressions. No differences were found in amygdala response. CONCLUSIONS: In contrast with previous research, this study found BOLD signal attenuation in the ventrolateral and medial prefrontal cortex and the anterior cingulate cortex during face emotion processing, consistent with a hypothesis of hypo-responsivity to external emotional stimuli in GAD. These decreases were in areas that have been implicated in emotion and cognition and may reflect an altered balance between internally and externally directed attentional processes.
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Transtornos de Ansiedade/psicologia , Mapeamento Encefálico , Emoções/fisiologia , Expressão Facial , Reconhecimento Visual de Modelos/fisiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância MagnéticaRESUMO
Soybean rust, caused by the fungus Phakopsora pachyrhizi, was detected on jicama (Pachyrhizus erosus L. Urban) for the first time in the United States in November 2009. The pathogen was observed on leaves of a single, potted jicama plant grown outdoors in a residential area and on leaves of all plants in a 12-m2 demonstration plot located at the Auburn University Teaching Garden in Auburn, AL. Symptoms on the upper leaf surfaces were isolated chlorotic areas near the leaf edges in the lower part of the canopy. The abaxial surface was first observed to exhibit brown lesions and subsequently produced volcano-shaped uredinia. These symptoms are consistent with a rust previously described on jicama in Mexico (1). Representative symptomatic plant tissue was sent to the USDA National Identification Services (Mycology) Laboratory in Beltsville, MD for diagnostic confirmation at both the Urbana, IL lab and the USDA National Plant Germplasm and Biotechnology Laboratory for DNA testing. From an infected leaf, samples of approximately 5 mm2 were excised from a microscopically observed rust lesion and an apparently noninfected area. Total DNA was purified with the FastDNA Spin Kit (MP Biomedicals, Solon, OH) followed by the E.Z.N.A. MicroElute DNA Clean-Up Kit (Omega Bio-tek, Inc, Doraville, GA) per manufacturer's instructions. Detection of P. pachyrhizi and P. meibomiae DNA was achieved by quantitative PCR using the method of Frederick et al. (2) and a DNA standard of previously prepared P. pachyrhizi spores. The observed rust pustule was found to contain P. pachyrhizi DNA in excess of 28,000 genomes, while no P. pachyrhizi DNA was observed from the asymptomatic sample. Both samples were negative for P. meibomiae. The fungal structures present were confirmed to be Phakopsora spp. DNA was extracted from sori aseptically removed from leaves with a Qiagen (Valencia, CA) DNeasy Plant Mini Kit and amplified with primers Ppa1 and NL4. The resulting partial ITS2 and 28S ribosomal RNA sequences were 100% identical to GenBank entry DQ354537 P. pachyrhizi internal transcribed spacer 2 and 28S ribosomal RNA gene, partial sequence. Sequences from jicama from Alabama were deposited in GenBank. Voucher specimens were deposited in the USDA Agricultural Research Service, National Fungus Collection (BPI). To our knowledge, this is the first report of the disease on jicama in the United States. References: (1) A. Cárcamo Rodriguez et al. Plant Dis. 90:1260, 2006. (2) R. D. Frederick et al. Phytopathology 92:217, 2002.
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OBJECTIVE: Reference values are usually defined based on blood samples from healthy men or nonpregnant women. This is not optimal as many biological markers changes during pregnancy and adequate reference values are of importance for correct clinical decisions. There are only few studies on the variations of laboratory tests during normal pregnancies, especially during the first two trimesters. It is thus a need to establish such reference values. DESIGN: Longitudinal study of laboratory markers in normal pregnancies. SETTING: Uppsala University Hospital, Sweden. POPULATION: Healthy pregnant females. METHODS: We have studied 25 frequently used laboratory tests during 52 normal pregnancies. Each woman was sampled up to nine times and the samples were divided according to collection time into the following groups: gestational week 7-17; week 17-24; week 24- 28; week 28-31; week 31-34; week 34-38; predelivery (0-2 weeks before delivery) and postpartum (> 6 weeks after delivery). The 2.5 and 97.5 percentiles for these markers were calculated according to the recommendations of the International Federation of Clinical Chemistry on the statistical treatment of reference values. RESULTS: Reference intervals are reported for plasma alanine aminotransferase, albumin, alkaline phosphatase, pancreas amylase, apolipoprotein A1, apolipoprotein B, aspartate aminotransferase, bilirubin, calcium, chloride, creatinine, cystatin C, ferritin, gamma-glutamyltransferase, iron, lactate dehydrogenase, magnesium, phosphate, potassium, sodium, transferrin, triglycerides, thyroid-stimulating hormone, urate and urea during these pregnancy periods. CONCLUSIONS: Most of the analytes change during normal pregnancy. It is thus of importance to use special reference values during pregnancy.
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Biomarcadores/análise , Gravidez/fisiologia , Diagnóstico Pré-Natal/normas , Adulto , Testes de Química Clínica/normas , Feminino , Humanos , Lactente , Recém-Nascido , Trimestres da Gravidez , Valores de ReferênciaRESUMO
A promising way to oppose infectious challenges would be to improve the resistance of the target species through genetic selection. Theoretically, a candidate gene is available against influenza viruses since a resistance trait was fortuitously discovered in the A2G mouse strain. This trait was demonstrated to be correlated with the expression of a specific isoform of the type I interferon (IFN)-dependent protein MX, an isoform coded by a specific allele at the mouse Mx1 locus. Two allelic polymorphisms were described recently in the Sus scrofa homologous gene. In this study, the frequencies and distribution of both alleles were evaluated among European domestic pig and wild boar populations by PCR-RFLP, and the anti-influenza activity conferred by both MX1 isoforms was evaluated in vitro using transfection of Vero cells followed by flow cytometric determination of the fraction of influenza virus-infected cells among MX-producing and MX-nonproducing cell populations. A significant difference in the anti-influenza activity brought by the two MX1 isoforms was demonstrated, which suggests that a significant improvement of innate resistance of pigs by genetic selection might be feasible provided the differences found here in vitro are epidemiologically relevant in vivo.
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Alelos , Proteínas de Ligação ao GTP/genética , Imunidade Inata/genética , Infecções por Orthomyxoviridae/genética , Locos de Características Quantitativas/genética , Sus scrofa/genética , Animais , Chlorocebus aethiops , Proteínas de Ligação ao GTP/imunologia , Humanos , Camundongos , Proteínas de Resistência a Myxovirus , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/veterinária , Locos de Características Quantitativas/imunologia , Sus scrofa/imunologia , Células VeroRESUMO
After 5 years of development, the European College of Veterinary Clinical Pathology (ECVCP) was formally recognized and approved on July 4, 2007 by the European Board of Veterinary Specialisation (EBVS), the European regulatory body that oversees specialization in veterinary medicine and which has approved 23 colleges. The objectives, committees, basis for membership, constitution, bylaws, information brochure and certifying examination of the ECVCP have remained unchanged during this time except as directed by EBVS. The ECVCP declared full functionality based on the following criteria: 1) a critical mass of 65 members: 15 original diplomates approved by the EBVS to establish the ECVCP, 37 de facto diplomates, 7 diplomates certified by examination, and 5 elected honorary members; 2) the development and certification of training programs, laboratories, and qualified supervisors for residents; currently there are 18 resident training programs in Europe; 3) administration of 3 annual board-certifying examinations thus far, with an overall pass rate of 70%; 4) European consensus criteria for assessing the continuing education of specialists every 5 years; 5) organization of 8 annual scientific congresses and a joint journal (with the American Society for Veterinary Clinical Pathology) for communication of scientific research and information; the College also maintains a website, a joint listserv, and a newsletter; 6) collaboration in training and continuing education with relevant colleges in medicine and pathology; 7) development and strict adherence to a constitution and bylaws compliant with the EBVS; and 8) demonstration of compelling rationale, supporting data, and the support of members and other colleges for independence as a specialty college. Formal EBVS recognition of ECVCP as the regulatory body for the science and practice of veterinary clinical pathology in Europe will facilitate growth and development of the discipline and compliance of academic, commercial diagnostic, and industry laboratories in veterinary clinical pathology. Future needs are in developing sponsorship for resident positions, increasing employment opportunities, increasing compliance with laboratory, training, and continuing education standards, and advancing relevant science and technology.
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Educação em Veterinária/tendências , Patologia Clínica/organização & administração , Sociedades/organização & administração , Medicina Veterinária/organização & administração , Europa (Continente)RESUMO
In May 2005, two commercial greenhouse flower growers, one in Louisiana (LA) and one in New York (NY), submitted coleus, Solenostemon scutellarioides (L.) Codd, plants for diagnosis after observing stunted growth, inward curling and twisting of leaves, and leaf abscission on multiple cultivars. Downy mildew-like growth was observable with hand lens or a microscope on the abaxial leaf surfaces of affected plants. Irregular necrotic spotting was present on some, but not all, plants on which sporulation was evident. Microscopic examination of LA material led to tentative identification of the pathogen as Peronospora lamii A. Braun (2). The pale brown conidia ranged from 17 to 26 × 15 to 26 µm (average 23 × 19 µm). Conidiophores ranged from 345 to 561 × 9 to 15 µm. No oospores were found. Additional coleus plants with downy mildew were subsequently found in three retail nurseries in LA in early summer. In NY, infected coleus plants were observed in landscapes in Farmington, Rochester, Ithaca, and in two commercial greenhouses between August and October 2005. NY samples sent to the USDA/APHIS in Beltsville, MD were examined, and the fungus was found to have morphology consistent with P. lamii. Two pathogenicity trials were conducted in NY. Conidia were rubbed from an infected coleus leaf onto the leaves of six healthy potted coleus plants of five cultivars and two basil plants that were placed in a shaded plastic tent in the greenhouse where temperatures ranged from 17 to 22°C. A household humidifier was used to supply mist inside the tent for 5 h per day. Six noninoculated plants of each coleus cultivar and two basil plants, placed in the same environment, served as controls. Downy mildew sporulation and some curling and twisting of leaves were observed 14 days after inoculation on all inoculated plants for three of the five cultivars (Florida Rustic Orange, Aurora Peach, and Aurora Mocha). Cvs. Florida Sun Rose and Lava showed no symptoms or signs of downy mildew. An irregularly shaped brown lesion developed on one inoculated basil leaf, and downy mildew sporulation was evident on the abaxial surface 35 days after inoculation. All noninoculated control plants remained disease free. In a second trial, conidia were rinsed from infected coleus leaves and sprayed onto the abaxial leaf surfaces of three coleus cv. Aurora Mocha plants. Three noninoculated plants served as controls and all were placed in a humidity tent. Leaf twisting and downy mildew sporulation were observed 13 days later on all inoculated plants, and control plants showed no sporulation or symptoms. A downy mildew causing disease of greenhouse-grown basil in Europe, originally identified as P. lamii on the basis of morphology, has recently been reported to be taxonomically distinguishable from P. lamii when tested by molecular methods (1). ITS sequences of coleus downy mildew from NY and LA were nearly identical (99% homology) to those of basil downy mildew from Switzerland and Italy (1). To our knowledge, this is the first report of downy mildew occurrence on coleus. References: (1) L. Belbahri et al. Mycol. Res. 109:1276, 2005. (2) S. M. Francis. Peronospora lamii. Descriptions of Pathogenic Fungi and Bacteria. No. 688. CMI, Kew, England, 1981.
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On November 4, 2004, soybean leaves (Glycine max (L.) Merr) were submitted to the Auburn University Plant Diagnostic Lab by a State Department of Agriculture and Industries Inspector. Samples were collected from an 80-ha field of soybean plants in a late-reproductive-growth stage in Mobile County, Alabama. Under microscopic examination, leaves showed rust pustules in advanced stages of development with urediniospores and sori characteristic of Phakopsora spp. Uredinia were ostiolate in small, brown, angular leaf spots (2 to 3 mm) on lower leaf surfaces. Urediniospores were pale yellow-to-white, globose or ovate, 20 to 40 × 15 to 25 µm. In a subsequent visit to the field, symptoms and signs of the rust disease were observed on plants bordering the edge of the field since the majority of plants were senescent. Tan lesions on lower leaf surfaces contained small pustules surrounded by a small zone of slightly discolored necrotic tissue. Masses of tan spores covered the lower leaf surface pustules. Leaves were mailed overnight to the USDA National Identification Services (Mycology) Laboratory in Beltsville, MD. The fungal structures were confirmed to be a Phakopsora sp., and the sample was forwarded to the USDA National Plant Germplasm and Biotechnology Laboratory in Beltsville, MD. DNA was extracted from leaf pieces containing sori using the Qiagen DNeasy Plant Mini kit (Qiagen, Valencia, CA). Phakopsora pachyrhizi was detected using a real-time polymerase chain reaction (PCR) protocol (1) performed in a Cepheid SmartCycler (Sunnyvale, CA). The PCR master mix was modified to include OmniMix beads (Cepheid). The field and microscopic suspect diagnosis of P. pachyrhizi was confirmed officially by APHIS on November 18, 2004. This was the fourth USDA official confirmation of Asian soybean rust in the continental United States during 2004, and to our knowledge, this is the first report of the disease in Alabama. This report helps confirm that early occurrences of Asian soybean rust in the United States were present in other areas in addition to the first reported finding in Louisiana (2). References: (1) R. D. Frederick et al. Phytopathology 92:217, 2002. (2) R. W. Schneider et al. Plant Dis. 89:774, 2005.
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The Asian soybean rust fungus, Phakopsora pachyrhizi H. Sydow & Sydow, was found on a 0.4-ha patch of kudzu (Pueraria lobata) near Dayton (Liberty County) in East Texas on November 2, 2005. Nearly 100% of the 300 leaflets examined were diseased with severity ranging from 5 to >100 lesions per leaflet. Eleven soybean fields as much as 20 km away were scouted and no infected plants were found. Asian soybean rust was also found on a 0.4-ha field of soybean (Glycine max cv. Vernal) on February 14, 2006 at the Texas A&M Agricultural Experiment Station in Weslaco (Hidalgo County) in the Lower Rio Grande Valley (LRGV) of Texas. Disease incidence was 100% (severity ranging from 5 to >100 lesions per leaflet) on 50 younger plants with green leaves along the edges of the field, whereas most of the plants in this field had senesced. These plants were not symptomatic and were at the R6 stage (full seed) when this field was previously scouted on December 19, 2005. Lesions on leaflets of kudzu and soybean were small and angular with erumpent uredinia typical of P. pachyrhizi. Urediniospores were ovoid or globose, hyaline, and measured 25 to 30 × 14 to 21 µm. Leaf samples with pustules were positive for P. pachyrhizi using enzyme-linked immunosorbent assay (ELISA) (Envirologix, Portland, ME). Morphological and polymerase chain reaction (PCR) identification of P. pachyrhizi from kudzu and soybean samples were confirmed by the USDA-APHIS-PPQ NIS and CPHST laboratories in Beltsville, MD as previously described (2). The kudzu in East Texas is not likely to support overwintering of the pathogen because it usually dies back during the winter. Leaves at this site were dead by January 17, 2006. This is the southernmost infestation of kudzu in Texas known to us. In contrast, the LRGV has a subtropical climate that would favor year-round survival of the fungus (3). This area, where 120 to 160 ha of soybeans are grown, may be a source of inoculum for soybean rust epidemics in the Midwest. Spore movement would follow the same pattern as seen with cereal rusts (1). However, soybeans are typically absent from the LRGV between late December and early March, so survival of the fungus during this interval would require other hosts. Regardless of whether the fungus overwinters here, or moves in from elsewhere, the LRGV spring crop could serve as an early indicator of a potential rust epidemic. References: (1) M. G. Eversmeyer and C. L. Kramer. Annu. Rev. Phytopathol. 38:491, 2000. (2) J. M. Mullen et al. Plant Dis. 90:112, 2006. (3) S. Pivonia et al. Plant Dis. 89:678, 2005.
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Asian soybean rust, caused by Phakopsora pachyrhizi Sydow, has been known to occur in the eastern hemisphere for nearly a century. More recently, it was reported from South America in 2002 and the continental United States in Louisiana in November 2004 (1,2). Subsequently, P. pachyrhizi was confirmed in Alabama, Arkansas, Georgia, Florida, Missouri, Mississippi, South Carolina, and Tennessee in 2004. Surveys conducted in North Carolina in late November 2004 failed to detect this pathogen. Symptoms of the disease were first observed on soybean (Glycine max (L.) Merr.) in North Carolina on 25 October 2005 in farmers' fields in the counties of Brunswick, Columbus, and Robeson. Typical pustules and urediniospores were readily apparent on infected leaves when viewed with a dissecting microscope. Urediniospores were obovoid to broadly ellipsoidal, hyaline to pale yellowish brown with a minutely echinulate thin wall, and measured 18 to 37 × 15 to 24 µm. This morphology is typical of soybean rust caused by P. pachyrhizi or P. meibomiae, the latter is a less aggressive species causing soybean rust in the western hemisphere (1). DNA was extracted from leaves containing sori using the Qiagen DNeasy Plant Mini kit (Valencia, CA). P. pachyrhizi was detected using a real-time polymerase chain reaction (PCR) protocol that differentiates between P. pachyrhizi and P. meibomiae in a Cepheid thermocycler (Sunnyvale, CA) with appropriate positive and negative controls. The PCR master mix was modified to include OmniMix beads (Cepheid). Field diagnosis of P. pachyrhizi was confirmed by the USDA/APHIS on 28 October 2005. Soybean rust was identified in subsequent surveys of soybean fields and leaf samples submitted by North Carolina Cooperative Extension Agents in an additional 15 counties. These samples also were assayed using a traditional PCR protocol and by the enzyme-linked immunosorbent assay protocol included in the EnviroLogix QualiPlate kit (Portland, ME) for soybean rust. Ten soybean specimens from 10 sites were confirmed positive by these methods. Disease was not found on three kudzu samples, although one kudzu sample was adjacent to a soybean field that was positive for P. pachyrhizi. Although soybean rust was eventually detected in 18 North Carolina counties in 2005, no soybean yield loss occurred since the pathogen was detected when more than 80% of the soybean crop was mature. To our knowledge, this is the first report of P. pachyrhizi in North Carolina and the northern most find on soybean in the continental United States in 2005. References: (1) R. D. Frederick et al. Phytopathology 92:217, 2002. (2) R. W. Schneider et al. Plant Dis. 89:774 2005.
RESUMO
Phakopsora pachyrhizi, the causal organism of soybean rust, was first observed in the continental United States on 6 November 2004 (2). On 11 November 2005, as part a national soybean rust monitoring effort, 75 leaves of kudzu (Pueraria montana var. lobata) were arbitrarily collected from a patch growing in Princeton, Caldwell County, Kentucky (37.106650°N, 87.886120°W) that had been periodically scouted for the presence of the disease since May 2005. Upon microscopic examination of the nonincubated sample, a small (Ë2.0 cm2) area of one leaf exhibited lesions, uredinia, and urediniospores characteristic of those reported for P. pachyrhizi (the Asian species) and P. meibomiae (the New World species) (2). No other infected leaves were observed despite repeated visits to the site and collection and observation of nearly 200 leaves. On 16 November 2005, one-half of the symptomatic tissue was sent by overnight courier to the USDA/APHIS/PPQ/NIS Laboratory, Beltsville, MD and the other half was sent to the Southern Plant Diagnostic Network Laboratory (SPDN), University of Florida, Gainesville. Both laboratories confirmed that the rust was a Phakopsora spp. on the basis of morphological examination. The preliminary polymerase chain reaction (PCR) testing conducted by the SPDN according to Harmon et al. (1) indicated the presence of P. pachyrhizi that was confirmed by the USDA/NPGBL using the validated modified real-time PCR assay described previously (2). The field diagnosis of P. pachyrhizi and preliminary PCR results were officially confirmed by USDA/APHIS on 18 November 2005. To our knowledge, this is the first report of P. pachyrhizi on kudzu or any host in Kentucky, and currently, the northernmost report of soybean rust on any host in the continental United States. References: (1) P. F. Harmon et al. On-line publication, doi:10.1094/PHP-2005-0613-O1-RS. Plant Health Progress, 2005. (2) R. W. Schneider et al. Plant Dis. 89:774, 2005.
RESUMO
Asian soybean rust, caused by Phakopsora pachyrhizi Sydow, has been known to occur in the eastern hemisphere for nearly a century. More recently, it was reported from Hawaii in 1994, eastern and southern Africa from 1996-1998, Nigeria in 2001, and Brazil and Paraguay in 2002. Aerobiological models suggested that urediniospores of the pathogen would be disseminated on wind currents to the continental United States in association with tropical storms if the disease became established north of the equator during hurricane season (U.S. Soybean Rust Detection and Aerobiological Modeling online publication at www.aphis.usda.gov/ppq/ ep/soybean_rust/ ). Since soybean rust was observed at approximately 5°N latitude in South America before several hurricanes impacted the continental United States in September 2004, it seems likely that the introduction was associated with at least one of these tropical storms, especially hurricane Ivan. Symptoms of the disease were first observed on soybean (Glycine max (L.) Merr.) in the continental United States on November 6, 2004 in a field near Baton Rouge, LA. Typical pustules and urediniospores on infected leaves were readily apparent when viewed with a dissecting microscope. Urediniospores were obovoid to broadly ellipsoidal, hyaline to pale yellowish brown with a minutely echinulate thin wall, and measured 18 to 37 × 15 to 24 µm. Paraphyses were cylindric to clavate and slightly thickened at the apex, colorless to pale yellowish brown, and 25-50 × 6-14 µm in size. This morphology is typical of Phakopsora pachyrhizi and P. meibomiae, a less aggressive, western hemisphere species (2). DNA was extracted from leaves containing sori using the Qiagen DNeasy Plant Mini kit. P. pachyrhizi was detected using a real-time polymerase chain reaction (PCR) protocol (1) that differentiates between P. pachyrhizi and P. meibomiae performed in a Cepheid thermocycler with appropriate positive and negative controls. The PCR master mix was modified to include OmniMix beads (Cepheid). The field diagnosis of P. pachyrhizi was confirmed officially by the USDA/APHIS on November 10, 2004, and this was followed on November 11, 2004 by a wide-ranging survey of soybean and kudzu (Pueraria sp.) in soybean production areas in southern and central Louisiana. Collections from this survey also were assayed as described above, and six soybean specimens from five sites were confirmed positive. The disease was not found on kudzu samples. To our knowledge, this is the first report of P. pachyrhizi in the continental United States. Voucher specimens have been placed in the USDA National Fungus Collection. References: (1) R. D. Frederick et al. Phytopathology 92:217, 2002. (2) Y. Ono et al. Mycol. Res. 96:825, 1992.
RESUMO
BACKGROUND: There are numerous methods for analyzing creatinine concentration in plasma, including the Jaffé alkaline picrate method in various modifications, enzymatic tests, and chromatographic methods. OBJECTIVE: The purpose of this study was to evaluate whether an enzymatic method could replace a Jaffé method for routine creatinine measurements in plasma from dogs, rats, and mice. The enzymatic method and a compensated Jaffé method were tested against a high-pressure liquid chromatography (HPLC) method, regarded as the gold standard for creatinine measurement. METHODS: Heparinized plasma samples were obtained from 20 beagle dogs, 20 Wistar rats, and 20 CD1-strain mice. The 2 test kits (Roche Diagnostics), Creatinine Jaffé Compensated and the enzymatic Creatinine Plus Version 2 reagent, were used on a Cobas Integra 400. The Jaffé compensated method used a calibration adjustment of 18 micromol/L to correct for the protein matrix in serum and plasma. The HPLC method was an isocratic method using a weak cation-exchange column following protein precipitation. RESULTS: Creatinine concentrations obtained using the enzymatic and the Jaffé methods differed significantly from the results obtained by the HPLC method. For dog plasma, mean values of 61.2, 61.8, and 67.8 micromol/L were obtained by the compensated Jaffé, enzymatic and HPLC methods, respectively. In the rat, respective mean values were 26.7, 21.9, and 23.0 micromol/L, and in the mouse, respective mean values were 14.2, 5.4, and 9.2 micromol/L. CONCLUSION: The enzymatic method can replace the Jaffé method for plasma creatinine determination in dogs, rats, and mice because results from the enzymatic method were closer to HPLC values than were those of the Jaffé method.
Assuntos
Técnicas de Laboratório Clínico/veterinária , Creatinina/sangue , Cães/sangue , Camundongos/sangue , Ratos/sangue , Animais , Cromatografia Líquida de Alta PressãoRESUMO
The kinetics and tissue distribution of 3H-heparin and a 3H-labelled low molecular weight heparin fragment were compared in normal rabbits as well as in rabbits with blocked renal function or reticuloendothelial system (RES). Radioactivity in plasma, urine, liver and kidneys, as well as anti-FXa activity in plasma were determined. The plasma elimination of heparin was, when compared to normal controls, prolonged both in rabbits with renal dysfunction as well as in rabbits with blocked RES, while renal dysfunction was the only parameter that significantly prolonged the plasma half-life of Fragmin. Studies on tissue distribution in normal rabbits revealed that about 60 per cent of the radioactive heparin dose accumulated in the liver and kidney three hours after the injection, whereas the corresponding value was less than 10 per cent for the Fragmin-derived radioactivity. The recovery of radioactivity in urine within three hours was 5 and 35 per cent of the dose, respectively, for 3H-heparin and 3H-Fragmin. It is concluded from the present study that the rapid plasma elimination of heparin in the rabbit (t1/2 = 17 minutes) is mainly due to a high tissue distribution (liver and kidney) while the plasma elimination of Fragmin (t1/2 = 28 minutes) is mainly caused by renal excretion.