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Subtropical Regions (subtropical + regions)
Selected AbstractsComparison of oxygen consumption in drosophilid flies from different climatesENTOMOLOGICAL SCIENCE, Issue 4 2006Ayako OIKAWA Abstract Oxygen consumption at rest was studied in drosophilid species from cool-temperate, warm-temperate and subtropical regions to assess whether adaptations to different climates are associated with changes in metabolic rates. In experiments at 23°C using 8-day-old males of 28 species, body mass was revealed to be a significant predictor of oxygen consumption. No significant relation was detected between mass-adjusted oxygen consumption and latitudinal distribution or thermal tolerance by either conventional regression analysis or a phylogenetically based method. The effect of temperature on oxygen consumption was studied with experiments at 15, 18, 23 and 28°C using 8- and 24-day-old males of four species of each of the montium species subgroup and the subgenus Drosophila. In these experiments, it was confirmed that temperature was a significant predictor of mass-adjusted oxygen consumption. In both lineages, mass-adjusted oxygen consumption was not higher in cool-temperate species than in subtropical species. Thus, adaptations to colder climates are not associated with elevation of metabolic rates in these drosophilid species. The results of the present study also indicate that oxygen consumption is not related to the capacity to walk quickly. [source] Structural Studies of the O-Chain Polysaccharide from Plesiomonas shigelloides Strain 302,73 (Serotype O1)EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 18 2008Giuseppina Pieretti Abstract Plesiomonas shigelloides is a Gram-negative bacterium belonging to the Enterobacteriaceae family. It has been found in an aquatic environment in the tropical and subtropical regions and is responsible for many gastrointestinal infections in humans, which take place from drinking untreated water or eating uncooked shellfish. Plesiomonas shigelloides has also been reported to provoke extraintestinal infections such as meningitis and bacteremia in immunocompromised adults and neonates. Despite the emerging importance of this pathogenic microorganism, only three different O-antigens have been characterised so far. The structure of the O-chain of the lipopolysaccharide (LPS) from Plesiomonasshigelloides strain 302,73 (serotype O1) was determined by chemical analysis, 1D and 2D NMR spectroscopy and MALDI-TOF mass spectrometry. The polysaccharide was constituted by a linear pentasaccharidic repeating unit as follows: ,3)-,- L -PneNAc4OAc(1,4)-,- L -FucNAc(1,4)-,- L -FucNAc(1,4)-,- L -FucNAc(1,3)-,- D -QuiNAc4NHb(1, (PneNAc = 2-acetamido-2,6-dideoxy-talose, Hb = (S)-3-hydroxybutanoyl) PneNAc O -acetylation was not stoichiometric and was found to be about 75,%. The position of the O -acetyl group and the amount of acetylation were deduced by NMR spectroscopic analysis. All the monosaccharides included in the repeating unit were deoxyamino sugars, which most probably, together with the presence of O -acetyl groups, were responsible for the recovery of the LPS in the phenol layer of the phenol/water extract of dried bacteria cells.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] The influence of the tropical and subtropical Atlantic and Pacific Oceans on precipitation variability over Southern Central South America on seasonal time scalesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 4 2004Guillermo J. Berri Abstract This paper studies the temporal and spatial patterns of precipitation anomalies over southern central South America (SCSA; 22,40°S and 54,70°W), and their relationship with the sea-surface temperature (SST) variability over the surrounding tropical and subtropical Atlantic and Pacific Oceans. The data include monthly precipitation from 68 weather stations in central,northern Argentina and neighbouring Brazil, Paraguay and Uruguay, and monthly SSTs from the NOAA dataset with a 2° resolution for the period 1961,93. We use the method of canonical correlation analysis (CCA) to study the simultaneous relationship between bi-monthly precipitation and SST variability. Before applying the CCA procedure, standardized anomalies are calculated and a prefiltering is applied by means of an empirical orthogonal function (EOF) analysis. Thus, the CCA input consists of 10 EOF modes of SST and between 9 and 11 modes for precipitation and their corresponding principal components, which are the minimum number of modes necessary to explain at least 80% of the variance of the corresponding field. The results show that November,December presents the most robust association between the SST and SCSA precipitation variability, especially in northeastern Argentina and southern Brazil, followed by March,April and May,June. The period January,February, in contrast, displays a weak relationship with the oceans and represents a temporal minimum of oceanic influence during the summer semester. Based on the CCA maps, we identify the different oceanic and SCSA regions, the regional averages of SST and precipitation are calculated, and linear correlation analysis are conducted. The periods with greater association between the oceans and SCSA precipitation are November,December and May,June. During November,December, every selected region over SCSA reflects the influence of several oceanic regions, whereas during May,June only a few regions show a direct association with the oceans. The Pacific Ocean regions have a greater influence and are more widespread over SCSA; the Atlantic Ocean regions have an influence only over the northwestern and the southeastern parts of SCSA. In general, the relationship with the equatorial and tropical Atlantic and Pacific Oceans is of the type warm,wet/cold,dry, whereas the subtropical regions of both oceans show the opposite relationship, i.e. warm,dry/cold,wet. Copyright © 2004 Royal Meteorological Society [source] Antimalarial compounds isolated from plants used in traditional medicineJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 11 2009Joanne Bero Abstract Objectives This review covers the compounds with antiplasmodial activity isolated from plants published from 2005 to the end of 2008, organized according to their phytochemical classes. Details are given for substances with IC50 values , 11 ,M. Key findings Malaria is a major parasitic disease in many tropical and subtropical regions and is responsible for more than 1 million deaths each year in Africa. The rapid spread of resistance encourages the search for new active compounds. Nature and particularly plants used in traditional medicine are a potential source of new antimalarial drugs as they contain molecules with a great variety of structures and pharmacological activities. Summary A large number of antimalarial compounds with a wide variety of structures have been isolated from plants and can play a role in the development of new antimalarial drugs. Ethnopharmacological approaches appear to be a promising way to find plant metabolites that could be used as templates for designing new derivatives with improved properties. [source] Practice Guidelines for Evaluation of Fever in Returning Travelers and MigrantsJOURNAL OF TRAVEL MEDICINE, Issue 2003Valérie D'Acremont Background Fever upon return from tropical or subtropical regions can be caused by diseases that are rapidly fatal if left untreated. The differential diagnosis is wide. Physicians often lack the necessary knowledge to appropriately take care of such patients. Objective To develop practice guidelines for the initial evaluation of patients presenting with fever upon return from a tropical or subtropical country in order to reduce delays and potential fatal outcomes and to improve knowledge of physicians. Target audience Medical personnel, usually physicians, who see the returning patients, primarily in an ambulatory setting or in an emergency department of a hospital and specialists in internal medicine, infectious diseases, and travel medicine. Method A systematic review of the literature,mainly extracted from the National Library of Medicine database,was performed between May 2000 and April 2001, using the keywords fever and/or travel and/or migrant and/or guidelines. Eventually, 250 articles were reviewed. The relevant elements of evidence were used in combination with expert knowledge to construct an algorithm with arborescence flagging the level of specialization required to deal with each situation. The proposed diagnoses and treatment plans are restricted to tropical or subtropical diseases (nonautochthonous diseases). The decision chart is accompanied with a detailed document that provides for each level of the tree the degree of evidence and the grade of recommendation as well as the key points of debate. Participants and consensus process Besides the 4 authors (2 specialists in travel/tropical medicine, 1 clinical epidemiologist, and 1 resident physician), a panel of 11 European physicians with different levels of expertise on travel medicine reviewed the guidelines. Thereafter, each point of the proposed recommendations was discussed with 15 experts in travel/tropical medicine from various continents. A final version was produced and submitted for evaluation to all participants. Conclusion Although the quality of evidence was limited by the paucity of clinical studies, these guidelines established with the support of a large and highly experienced panel should help physicians to deal with patients coming back from the Tropics with fever. [source] Development of microsatellite markers in Rhizophora stylosa using a dual-suppression-polymerase chain reaction techniqueMOLECULAR ECOLOGY RESOURCES, Issue 1 2004M. S. Islam Abstract Rhizophora stylosa is an ecologically important mangrove tree species that is found in tropical and subtropical regions. We isolated five polymorphic microsatellite loci from R. stylosa using a dual-suppression-polymerase chain reaction technique. These loci provided microsatellite markers with polymorphism of four alleles in each locus for overall population. The mean expected heterozygosities ranged from 0.113 to 0.473. [source] The isolation of microsatellite loci in the Mediterranean fruitfly Ceratitis capitata (Diptera: Tephritidae) using a biotin/streptavidin enrichment techniqueMOLECULAR ECOLOGY RESOURCES, Issue 3 2001D. G. Casey Abstract The Medfly (Ceratitis capitata) is a polyphagous dipteran pest which has spread from North Africa to the countries of the Mediterranean Basin and has also invaded tropical and subtropical regions throughout the world. Colonizing populations typically possess low levels of genetic variability. Microsatellites provide an effective means of investigating the population structure of such genetically depauperate populations, however, microsatellite markers traditionally require a long phase of development in new taxa. We used a biotin/streptavidin capture technique to isolate microsatellites directly from C. capitata genomic DNA and we describe here the identification of seven polymorphic microsatellite markers in C. capitata. [source] Botrytis cinerea: the cause of grey mould diseaseMOLECULAR PLANT PATHOLOGY, Issue 5 2007BRIAN WILLIAMSON SUMMARY Introduction:,Botrytis cinerea (teleomorph: Botryotinia fuckeliana) is an airborne plant pathogen with a necrotrophic lifestyle attacking over 200 crop hosts worldwide. Although there are fungicides for its control, many classes of fungicides have failed due to its genetic plasticity. It has become an important model for molecular study of necrotrophic fungi. Taxonomy:, Kingdom: Fungi, phylum: Ascomycota, subphylum: Pezizomycotina, class: Leotiomycetes, order: Helotiales, family: Sclerotiniaceae, genus: Botryotinia. Host range and symptoms: Over 200 mainly dicotyledonous plant species, including important protein, oil, fibre and horticultural crops, are affected in temperate and subtropical regions. It can cause soft rotting of all aerial plant parts, and rotting of vegetables, fruits and flowers post-harvest to produce prolific grey conidiophores and (macro)conidia typical of the disease. Pathogenicity:,B. cinerea produces a range of cell-wall-degrading enzymes, toxins and other low-molecular-weight compounds such as oxalic acid. New evidence suggests that the pathogen triggers the host to induce programmed cell death as an attack strategy. Resistance:, There are few examples of robust genetic host resistance, but recent work has identified quantitative trait loci in tomato that offer new approaches for stable polygenic resistance in future. Useful websites:,http://www.phi-base.org/query.php, http://www.broad.mit.edu/annotation/genome/botrytis_cinerea/Home.html, http://urgi.versailles.inra.fr/projects/Botrytis/, http://cogeme.ex.ac.uk [source] Physiology and molecular aspects of Verticillium wilt diseases caused by V. dahliae and V. albo-atrumMOLECULAR PLANT PATHOLOGY, Issue 2 2006EMILIE F. FRADIN SUMMARY Introduction:,Verticillium spp. are soil-borne plant pathogens responsible for Verticillium wilt diseases in temperate and subtropical regions; collectively they affect over 200 hosts, including many economically important crops. There are currently no fungicides available to cure plants once they are infected. Taxonomy:, Kingdom: Fungi, phylum: Ascomycota, subphylum, Pezizomycotina, class: Sordariomycetes, order: Phyllachorales, genus: Verticillium. Host range and disease symptoms:, Over 200 mainly dicotyledonous species including herbaceous annuals, perennials and woody species are host to Verticillium diseases. As Verticillium symptoms can vary between hosts, there are no unique symptoms that belong to all plants infected by this fungus. Disease symptoms may comprise wilting, chlorosis, stunting, necrosis and vein clearing. Brown vascular discoloration may be observed in stem tissue cross-sections. Pathogenicity:,Verticillium spp. have been reported to produce cell-wall-degrading enzymes and phytotoxins that all have been implicated in symptom development. Nevertheless, evidence for a crucial role of toxins in pathogenicity is inconsistent and therefore not generally accepted. Microsclerotia and melanized mycelium play an important role in the disease cycle as they are a major inoculum source and are the primary long-term survival structures. Resistance:, Different defence responses in the prevascular and the vascular stage of Verticillium wilt diseases determine resistance. Although resistance physiology is well established, the molecular processes underlying this physiology remain largely unknown. Resistance against Verticillium largely depends on the isolation of the fungus in contained parts of the xylem tissues followed by subsequent elimination of the fungus. Although genetic resistance has been described in several plant species, only one resistance locus against Verticillium has been cloned to date. Useful website:,http://cbr-rbc.nrc-cnrc.gc.ca/services/cogeme/ [source] Soft rot erwiniae: from genes to genomesMOLECULAR PLANT PATHOLOGY, Issue 1 2003Ian K. Toth SUMMARY The soft rot erwiniae, Erwinia carotovora ssp. atroseptica (Eca), E. carotovora ssp. carotovora (Ecc) and E. chrysanthemi (Ech) are major bacterial pathogens of potato and other crops world-wide. We currently understand much about how these bacteria attack plants and protect themselves against plant defences. However, the processes underlying the establishment of infection, differences in host range and their ability to survive when not causing disease, largely remain a mystery. This review will focus on our current knowledge of pathogenesis in these organisms and discuss how modern genomic approaches, including complete genome sequencing of Eca and Ech, may open the door to a new understanding of the potential subtlety and complexity of soft rot erwiniae and their interactions with plants. Taxonomy: ,The soft rot erwiniae are members of the Enterobacteriaceae, along with other plant pathogens such as Erwinia amylovora and human pathogens such as Escherichia coli, Salmonella spp. and Yersinia spp. Although the genus name Erwinia is most often used to describe the group, an alternative genus name Pectobacterium was recently proposed for the soft rot species. Host range:,Ech mainly affects crops and other plants in tropical and subtropical regions and has a wide host range that includes potato and the important model host African violet ( Saintpaulia ionantha ). Ecc affects crops and other plants in subtropical and temperate regions and has probably the widest host range, which also includes potato. Eca , on the other hand, has a host range limited almost exclusively to potato in temperate regions only. Disease symptoms: ,Soft rot erwiniae cause general tissue maceration, termed soft rot disease, through the production of plant cell wall degrading enzymes. Environmental factors such as temperature, low oxygen concentration and free water play an essential role in disease development. On potato, and possibly other plants, disease symptoms may differ, e.g. blackleg disease is associated more with Eca and Ech than with Ecc. Useful websites: ,http://www.scri.sari.ac.uk/TiPP/Erwinia.htm, http://www.ahabs.wisc.edu:16080/pernalab/erwinia/index.htm, http://www.tigr.org/tdb/mdb/mdbinprogress.html, http://www.sanger.ac.uk/Projects/E_carotovora/. [source] Rapid analysis of Jatropha curcas gene functions by virus-induced gene silencingPLANT BIOTECHNOLOGY JOURNAL, Issue 9 2009Jian Ye Summary Jatropha curcas L. is a small, woody tree of the Euphorbiaceae family. This plant can grow on marginal land in the tropical and subtropical regions and produces seeds containing up to 30% oil. Several Asian countries have selected Jatropha for large scale planting as a biodiesel feedstock. Nevertheless, Jatropha also possesses several undesirable traits that may limit its wide adoption. An improved understanding of plant development and the regulation of fatty acid (FA) and triacylglyceride biosynthesis in Jatropha is particularly facilitative for the development of elite crops. Here, we show that a tobacco rattle virus (TRV) vector can trigger virus-induced gene silencing (VIGS) in Jatropha. Our optimized method produced robust and reliable gene silencing in plants agroinoculated with recombinant TRV harbouring Jatropha gene sequences. We used VIGS to investigate possible functions of 13 Jatropha genes of several functional categories, including FA biosynthesis, developmental regulation and toxin biosynthesis, etc. Based on the effects of VIGS on the FA composition of newly emerged leaves, we determined the function of several genes implicated in FA biosynthesis. Moreover, VIGS was able to discriminate independent functions of related gene family members. Our results show that VIGS can be used for high-throughput screening of Jatropha genes whose functions can be assayed in leaves. [source] Pyramiding of genes conferring resistance to Tomato yellow leaf curl virus from different wild tomato speciesPLANT BREEDING, Issue 6 2008F. Vidavski Abstract Tomato (Solanum lycopersicum) production in tropical and subtropical regions of the world is limited by the endemic presence of Tomato yellow leaf curl virus (TYLCV). Breeding programmes aimed at producing TYLCV-resistant tomato cultivars have utilized resistance sources derived from wild tomato species. So far, all reported breeding programmes have introgressed TYLCV resistance from a single wild tomato source. Here, we tested the hypothesis that pyramiding resistances from different wild tomato species might improve the degree of resistance of the domesticated tomato to TYLCV. We have crossed TYLCV-resistant lines that originated from different wild tomato progenitors, Solanum chilense, Solanum peruvianum, Solanum pimpinellifolium, and Solanum habrochaites. The various parental resistant lines and the F1 hybrids were inoculated in the greenhouse using viruliferous whiteflies. Control, non-inoculated plants of the same lines and hybrids were exposed to non-viruliferous whiteflies. Following inoculation, the plants were scored for disease symptom severity, and transplanted to the field. Resistance was assayed by comparing yield of inoculated plants to those of the control non-inoculated plants of the same variety. Results showed that the F1 hybrids between the resistant lines and the susceptible line suffered major yield reduction because of infection, but all hybrids were more resistant than the susceptible parent. All F1 hybrids resulting from a cross between two resistant parents, showed a relatively high level of resistance, which in most cases was similar to that displayed by the more resistant parent. In some cases, the hybrids displayed better levels of resistance than both parents, but the differences were not statistically significant. The F1 hybrid between a line with resistance from S. habrochaites and a line with resistance from S. peruvianum (HAB and 72-PER), exhibited the lowest yield loss and the mildest level of symptoms. Although the resistance level of this F1 hybrid was not statistically different from the level of resistance displayed by the 72-PER parent itself, it was statistically better than the level of resistance displayed by the F1 hybrids between 72-PER and any other resistant or susceptible line. [source] Variation and genetics of tolerance to cull fruit formation in slicing cucumberPLANT BREEDING, Issue 4 2004N. P. S. Dhillon Abstract Cull fruit formation (CFF) in cucumber is a serious problem in subtropical regions. A world collection of cucumber was evaluated in the field for tolerance to CFF over 2 years. Tolerance was identified in landraces collected from the centre of origin (India). Highly significant genotypic effects for tolerance to CFF were observed. The data revealed the presence of genetic variability among cucumber inbreds for tolerance to CFF, which would be useful to develop CFF-tolerant varieties or hybrids. Genotype-by-environment interaction for tolerance to CFF was not detected. Twenty-one F1 hybrids evaluated for tolerance to CFF indicated the dominance of a low CFF trait which appears to be controlled by many dominant genes. The in breds ,JL-1', ,JL-2' and ,JL-11' would be good choices as parents for developing CFF-tolerant cucumber hybrids. [source] Erratum: M.M.M. Okumura, C.H.C. Boyadjian and S. Eggers (2007) Auditory exostoses as an aquatic activity marker: A comparison of coastal and inland skeletal remains from tropical and subtropical regions of Brazil.AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2007No abstract is available for this article. [source] Larvicidal Effects of Fungal Meroterpenoids in the Control of Aedes aegypti L., the Main Vector of Dengue and Yellow FeverCHEMISTRY & BIODIVERSITY, Issue 2 2008Regina Geris Abstract The mosquito Aedes aegypti is an increasing problem of public health, being the vector responsible for dengue and Yellow Fever in tropical and subtropical regions. The aim of this work was to determine the potential larvicidal activity of a series of meroterpenoids, compounds 1,7, previously obtained fungal secondary metabolites from Penicillium sp., against the third-instar larvae of A. aegypti. The lethal concentrations (LC50 and LC90) of 1,7 were evaluated 24,h after exposure. Dehydroaustin (4) was the most active meroterpenoid in the series, with an LC50 value of 2.9,ppm, making it an attractive natural insecticide. [source] Seasonal influenza activity in Hong Kong and its association with meteorological variationsJOURNAL OF MEDICAL VIROLOGY, Issue 10 2009Paul K.S. Chan Abstract Influenza seasons appear consistently in the temperate regions, but are more variable in tropical/subtropical regions. The determinant for such variation remains poorly understood. This study documented the activity of influenza over a 10-year period in Hong Kong; examining its association with changes in temperature and relative humidity. The two types of influenza exhibited different correlations with meteorological variations. Influenza A showed two seasonal peaks occurring respectively in winter/spring and summer months in most years. Influenza B showed a clear winter/spring peak, but its activity during summer months was more variable. Cold and humid conditions were associated with a higher activity of both influenza A and B. In contrast, hot and humid conditions were associated with a higher activity of influenza A, but were associated with only a moderate, less consistent increase in the activity of influenza B. A trend of increase in the magnitude of summer peaks of influenza A, but not influenza B, was observed. A hypothetical 2°C rise in temperature would decrease the proportion of favorable days for influenza A in December,April from 78% to 57%, but an increase from 58% to 71% in May,November; with a similar effect (from 83% to 62%) for influenza B during December,April, but a modest change (from 17% to 18%) during May,November. The presence of two seasonal peaks of influenza annually emphasizes the need to evaluate the duration of protective immunity offered by vaccination. Further study on the effects of climate change and global warming on the activity of influenza is warranted. J. Med. Virol. 81:1797,1806, 2009. © 2009 Wiley-Liss, Inc. [source] | ||||||||||||||||