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1.
Dentomaxillofac Radiol ; 51(6): 20220044, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-35522698

ABSTRACT

OBJECTIVE: To determine the capacity of ultrasonographic image-based measurements of gingival height and alveolar bone level for monitoring periodontal health and disease. METHODS: Sixteen subjects were recruited from patients scheduled to receive dental care and classified as periodontally healthy (n = 10) or diseased (n = 6) according to clinical guidelines. A 40-MHz ultrasound system was used to measure gingival recession, gingival height, alveolar bone level, and gingival thickness from 66 teeth for comparison to probing measurements of pocket depth and clinical attachment level. Interexaminer variability and comparison between ultrasound measurements and probing measurements was performed via Bland-Altman analysis. RESULTS: Gingival recession and its risk in non-recessed patients could be determined via measurement of the supra- and subgingival cementoenamel junction relative to the gingival margin. Interexaminer bias for ultrasound image analysis was negligible (<0.10 mm) for imaged gingival height (iGH) and 0.45 mm for imaged alveolar bone level (iABL). Diseased subjects had significantly higher imaging measurements (iGH, iABL) and clinical measurements (probing pocket depth, clinical attachment level) than healthy subjects (p < 0.05). Subtraction of the average biologic width from iGH resulted in 83% agreement (≤1 mm difference) between iGH and probing pocket depth measurements. CONCLUSIONS: Ultrasonography has an equivalent diagnostic capacity as gold-standard physical probing for periodontal metrics while offering more detailed anatomical information.


Subject(s)
Gingival Recession , Periodontitis , Biomarkers , Gingiva/diagnostic imaging , Humans , Periodontal Attachment Loss/diagnostic imaging , Periodontal Pocket/diagnostic imaging , Ultrasonography
2.
ACS Appl Mater Interfaces ; 13(13): 14974-14984, 2021 Apr 07.
Article in English | MEDLINE | ID: mdl-33761255

ABSTRACT

Photoacoustic (PA) imaging holds great promise as a noninvasive imaging modality. Gold nanorods (GNRs) with absorption in the second near-infrared (NIR-II) window have emerged as excellent PA probes because of their tunable optical absorption, surface modifiability, and low toxicity. However, pristine GNRs often undergo shape transition upon laser illumination due to thermodynamic instability, leading to a reduced PA signal after a few seconds of imaging. Here, we report monodisperse GNR-melanin nanohybrids where a tunable polydopamine (PDA) coating was conformally coated on GNRs. GNR@PDAs showed a threefold higher PA signal than pristine GNRs due to the increased optical absorption, cross-sectional area, and thermal confinement. More importantly, the PA signal of GNR@PDAs only decreased by 29% during the 5 min of laser illumination in the NIR-II window, while significant attenuation (77%) was observed for GNRs. The GNR@PDAs maintained 87% of its original PA signal in vivo even after 10 min of laser illumination. This PDA-enabled strategy affords a rational design for robust PA imaging probes and provides more opportunities for other types of photomediated biomedicines, such as photothermal and photodynamic regimens.


Subject(s)
Gold/chemistry , Melanins/chemistry , Nanotubes/chemistry , Animals , Indoles/chemistry , Infrared Rays , Mice , Nanotubes/ultrastructure , Photoacoustic Techniques/methods , Polymers/chemistry
3.
Fungal Syst Evol ; 6: 1-24, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32904189

ABSTRACT

The Genera of Fungi series, of which this is the sixth contribution, links type species of fungal genera to their morphology and DNA sequence data. Five genera of microfungi are treated in this study, with new species introduced in Arthrographis, Melnikomyces, and Verruconis. The genus Thysanorea is emended and two new species and nine combinations are proposed. Kramasamuha sibika, the type species of the genus, is provided with DNA sequence data for first time and shown to be a member of Helminthosphaeriaceae (Sordariomycetes). Aureoconidiella is introduced as a new genus representing a new lineage in the Dothideomycetes.

4.
Clin Microbiol Infect ; 25(11): 1356-1363, 2019 Nov.
Article in English | MEDLINE | ID: mdl-30910716

ABSTRACT

BACKGROUND: Antimicrobial resistance (AMR) is one of the greatest threats in 21st century medicine. AMR has been characterized as a social dilemma. A familiar version describes the situation in which a collective resource (in this case, antibiotic efficacy) is exhausted due to over-exploitation. The dilemma arises because individuals are motivated to maximize individual payoffs, although the collective outcome is worse if all act in this way. OBJECTIVES: We aim to outline the implications for antimicrobial stewardship of characterizing antibiotic overuse as a social dilemma. SOURCES: We conducted a narrative review of the literature on interventions to promote the conservation of resources in social dilemmas. CONTENT: The social dilemma of antibiotic over-use is complicated by the lack of visibility and imminence of AMR, a loose coupling between individual actions and the outcome of AMR, and the agency relationships inherent in the prescriber role. We identify seven strategies for shifting prescriber behaviour and promoting a focus on the collectively desirable outcome of conservation of antibiotic efficacy: (1) establish clearly defined boundaries and access rights; (2) raise the visibility and imminence of the problem; (3) enable collective choice arrangements; (4) conduct behaviour-based monitoring; (5) use social and reputational incentives and sanctions; (6) address misalignment of goals and incentives; and (7) provide conflict resolution mechanisms. IMPLICATIONS: We conclude that this theoretic analysis of antibiotic stewardship could make the problem of optimizing antibiotic prescribing more tractable, providing a theory base for intervention development.


Subject(s)
Anti-Infective Agents/therapeutic use , Antimicrobial Stewardship/organization & administration , Drug Resistance, Microbial , Drug Utilization/standards , Humans
5.
J Hosp Infect ; 101(4): 428-439, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30099092

ABSTRACT

BACKGROUND: Antimicrobial resistance is a global health threat, partly driven by inappropriate antibiotic prescriptions for acute medical patients in hospitals. AIM: To provide a systematic review of qualitative research on antibiotic prescribing decisions in hospitals worldwide, including broad-spectrum antibiotic use. METHODS: A systematic search of qualitative research on antibiotic prescribing for adult hospital patients published between 2007 and 2017 was conducted. Drawing on the Health Belief Model, a framework synthesis was conducted to assess threat perceptions associated with antimicrobial resistance, and perceived benefits and barriers associated with antibiotic stewardship. FINDINGS: The risk of antimicrobial resistance was generally perceived to be serious, but the abstract and long-term nature of its consequences led physicians to doubt personal susceptibility. While prescribers believed in the benefits of optimizing prescribing, the direct link between over-prescribing and antimicrobial resistance was questioned, and prescribers' behaviour change was frequently considered futile when fighting the complex problem of antimicrobial resistance. The salience of individual patient risks was a key barrier to more conservative prescribing. Physicians perceived broad-spectrum antibiotics to be effective and low risk; prescribing broad-spectrum antibiotics involved low cognitive demand and enabled physicians to manage patient expectations. Antibiotic prescribing decisions in low-income countries were shaped by a context of heightened uncertainty and risk due to poor microbiology and infection control services. CONCLUSIONS: When tackling antimicrobial resistance, the tensions between immediate individual risks and long-term collective risks need to be taken into account. Efforts to reduce diagnostic uncertainty and to change risk perceptions will be critical in shifting practice.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Attitude of Health Personnel , Drug Utilization/statistics & numerical data , Drug Utilization/standards , Practice Patterns, Physicians' , Female , Hospitals , Humans , Male , Qualitative Research
6.
J Viral Hepat ; 25(11): 1287-1297, 2018 11.
Article in English | MEDLINE | ID: mdl-29888827

ABSTRACT

In March 2016, the Australian government offered unrestricted access to direct-acting antiviral (DAA) therapy for chronic hepatitis C virus (HCV) to the entire population. This included prescription by any medical practitioner in consultation with specialists until sufficient experience was attained. We sought to determine the outcomes and experience over the first twelve months for the entire state of South Australia. We performed a prospective, observational study following outcomes of all treatments associated with the state's four main tertiary centres. A total of 1909 subjects initiating DAA therapy were included, representing an estimated 90% of all treatments in the state. Overall, SVR12 was 80.4% in all subjects intended for treatment and 95.7% in those completing treatment and follow-up. 14.2% were lost to follow-up (LTFU) and did not complete SVR12 testing. LTFU was independently associated with community treatment via remote consultation (OR 1.50, 95% CI 1.04-2.18, P = .03), prison-based treatment (OR 2.02, 95% CI 1.08-3.79, P = .03) and younger age (OR 0.98, 95% CI 0.97-0.99, P = .05). Of the 1534 subjects completing treatment and follow-up, decreased likelihood of SVR12 was associated with genotype 2 (OR 0.23, 95% CI 0.07-0.74, P = .01) and genotype 3 (OR 0.23, 95% CI 0.12-0.43, P ≤ .01). A significant decrease in treatment initiation was observed over the twelve-month period in conjunction with a shift from hospital to community-based treatment. Our findings support the high responses observed in clinical trials; however, a significant gap exists in SVR12 in our real-world cohort due to LTFU. A declining treatment initiation rate and shift to community-based treatment highlight the need to explore additional strategies to identify, treat and follow-up remaining patients in order to achieve elimination targets.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis C, Chronic/drug therapy , Antiviral Agents/pharmacology , Continuity of Patient Care , Female , Genotype , Hepacivirus/drug effects , Hepacivirus/genetics , Hepatitis C, Chronic/epidemiology , Hepatitis C, Chronic/virology , Humans , Intention to Treat Analysis , Lost to Follow-Up , Male , Middle Aged , Outcome and Process Assessment, Health Care , Prospective Studies , South Australia/epidemiology , Sustained Virologic Response
7.
Persoonia ; 41: 238-417, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30728607

ABSTRACT

Novel species of fungi described in this study include those from various countries as follows: Angola, Gnomoniopsis angolensis and Pseudopithomyces angolensis on unknown host plants. Australia, Dothiora corymbiae on Corymbia citriodora, Neoeucasphaeria eucalypti (incl. Neoeucasphaeria gen. nov.) on Eucalyptus sp., Fumagopsis stellae on Eucalyptus sp., Fusculina eucalyptorum (incl. Fusculinaceae fam. nov.) on Eucalyptus socialis, Harknessia corymbiicola on Corymbia maculata, Neocelosporium eucalypti (incl. Neocelosporium gen. nov., Neocelosporiaceae fam. nov. and Neocelosporiales ord. nov.) on Eucalyptus cyanophylla, Neophaeomoniella corymbiae on Corymbia citriodora, Neophaeomoniella eucalyptigena on Eucalyptus pilularis, Pseudoplagiostoma corymbiicola on Corymbia citriodora, Teratosphaeria gracilis on Eucalyptus gracilis, Zasmidium corymbiae on Corymbia citriodora. Brazil, Calonectria hemileiae on pustules of Hemileia vastatrix formed on leaves of Coffea arabica, Calvatia caatinguensis on soil, Cercospora solani-betacei on Solanum betaceum, Clathrus natalensis on soil, Diaporthe poincianellae on Poincianella pyramidalis, Geastrum piquiriunense on soil, Geosmithia carolliae on wing of Carollia perspicillata, Henningsia resupinata on wood, Penicillium guaibinense from soil, Periconia caespitosa from leaf litter, Pseudocercospora styracina on Styrax sp., Simplicillium filiforme as endophyte from Citrullus lanatus, Thozetella pindobacuensis on leaf litter, Xenosonderhenia coussapoae on Coussapoa floccosa. Canary Islands (Spain), Orbilia amarilla on Euphorbia canariensis. Cape Verde Islands, Xylodon jacobaeus on Eucalyptus camaldulensis. Chile, Colletotrichum arboricola on Fuchsia magellanica. Costa Rica, Lasiosphaeria miniovina on tree branch. Ecuador, Ganoderma chocoense on tree trunk. France, Neofitzroyomyces nerii (incl. Neofitzroyomyces gen. nov.) on Nerium oleander. Ghana, Castanediella tereticornis on Eucalyptus tereticornis, Falcocladium africanum on Eucalyptus brassiana, Rachicladosporium corymbiae on Corymbia citriodora. Hungary, Entoloma silvae-frondosae in Carpinus betulus-Pinus sylvestris mixed forest. Iran, Pseudopyricularia persiana on Cyperus sp. Italy, Inocybe roseascens on soil in mixed forest. Laos, Ophiocordyceps houaynhangensis on Coleoptera larva. Malaysia, Monilochaetes melastomae on Melastoma sp. Mexico, Absidia terrestris from soil. Netherlands, Acaulium pannemaniae, Conioscypha boutwelliae, Fusicolla septimanifiniscientiae, Gibellulopsis simonii, Lasionectria hilhorstii, Lectera nordwiniana, Leptodiscella rintelii, Parasarocladium debruynii and Sarocladium dejongiae (incl. Sarocladiaceae fam. nov.) from soil. New Zealand, Gnomoniopsis rosae on Rosa sp. and Neodevriesia metrosideri on Metrosideros sp. Puerto Rico, Neodevriesia coccolobae on Coccoloba uvifera, Neodevriesia tabebuiae and Alfaria tabebuiae on Tabebuia chrysantha. Russia, Amanita paludosa on bogged soil in mixed deciduous forest, Entoloma tiliae in forest of Tilia × europaea, Kwoniella endophytica on Pyrus communis. South Africa, Coniella diospyri on Diospyros mespiliformis, Neomelanconiella combreti (incl. Neomelanconiellaceae fam. nov. and Neomelanconiella gen. nov.) on Combretum sp., Polyphialoseptoria natalensis on unidentified plant host, Pseudorobillarda bolusanthi on Bolusanthus speciosus, Thelonectria pelargonii on Pelargonium sp. Spain, Vermiculariopsiella lauracearum and Anungitopsis lauri on Laurus novocanariensis, Geosmithia xerotolerans from a darkened wall of a house, Pseudopenidiella gallaica on leaf litter. Thailand, Corynespora thailandica on wood, Lareunionomyces loeiensis on leaf litter, Neocochlearomyces chromolaenae (incl. Neocochlearomyces gen. nov.) on Chromolaena odorata, Neomyrmecridium septatum (incl. Neomyrmecridium gen. nov.), Pararamichloridium caricicola on Carex sp., Xenodactylaria thailandica (incl. Xenodactylariaceae fam. nov. and Xenodactylaria gen. nov.), Neomyrmecridium asiaticum and Cymostachys thailandica from unidentified vine. USA, Carolinigaster bonitoi (incl. Carolinigaster gen. nov.) from soil, Penicillium fortuitum from house dust, Phaeotheca shathenatiana (incl. Phaeothecaceae fam. nov.) from twig and cone litter, Pythium wohlseniorum from stream water, Superstratomyces tardicrescens from human eye, Talaromyces iowaense from office air. Vietnam, Fistulinella olivaceoalba on soil. Morphological and culture characteristics along with DNA barcodes are provided.

8.
Physiol Biochem Zool ; 90(2): 257-272, 2017.
Article in English | MEDLINE | ID: mdl-28277961

ABSTRACT

Sharks migrate annually over large distances and occupy a wide variety of habitats, complicating analysis of lifestyle and diet. A biogeochemical technique often used to reconstruct shark diet and environment preferences is stable isotope analysis, which is minimally invasive and integrates through time and space. There are previous studies that focus on isotopic analysis of shark soft tissues, but there are limited applications to shark teeth. However, shark teeth offer an advantage of multiple ecological snapshots and minimum invasiveness during removal because of their distinct conveyor belt tooth replacement system. In this study, we analyze δ13C and δ15N values of the organic matrix in leopard shark teeth (Triakis semifasciata) from a captive experiment and report discrimination factors as well as incorporation rates. We found differences in tooth discrimination factors for individuals fed different prey sources (mean ± SD; Δ13Csquid = 4.7‰ ± 0.5‰, Δ13Ctilapia = 3.1‰ ± 1.0‰, Δ15Nsquid = 2.0‰ ± 0.7‰, Δ15Ntilapia = 2.8‰ ± 0.6‰). In addition, these values differed from previously published discrimination factors for plasma, red blood cells, and muscle of the same leopard sharks. Incorporation rates of shark teeth were similar for carbon and nitrogen (mean ± SE; λC = 0.021 ± 0.009, λN = 0.024 ± 0.007) and comparable to those of plasma. We emphasize the difference in biological parameters on the basis of tissue substrate and diet items to interpret stable isotope data and apply our results to stable isotope values from blue shark (Prionace glauca) teeth to illustrate the importance of biological parameters to interpret the complex ecology of a migratory shark.


Subject(s)
Carbon/metabolism , Nitrogen/metabolism , Sharks/physiology , Tooth/chemistry , Animal Feed , Animals , Carbon Isotopes , Nitrogen Isotopes , Tooth/metabolism
9.
Persoonia ; 39: 270-467, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29503478

ABSTRACT

Novel species of fungi described in this study include those from various countries as follows: Antarctica: Cadophora antarctica from soil. Australia: Alfaria dandenongensis on Cyperaceae, Amphosoma persooniae on Persoonia sp., Anungitea nullicana on Eucalyptus sp., Bagadiella eucalypti on Eucalyptus globulus, Castanediella eucalyptigena on Eucalyptus sp., Cercospora dianellicola on Dianella sp., Cladoriella kinglakensis on Eucalyptus regnans, Cladoriella xanthorrhoeae (incl. Cladoriellaceae fam. nov. and Cladoriellales ord. nov.) on Xanthorrhoea sp., Cochlearomyces eucalypti (incl. Cochlearomyces gen. nov. and Cochlearomycetaceae fam. nov.) on Eucalyptus obliqua, Codinaea lambertiae on Lambertia formosa, Diaporthe obtusifoliae on Acacia obtusifolia, Didymella acaciae on Acacia melanoxylon, Dothidea eucalypti on Eucalyptus dalrympleana, Fitzroyomyces cyperi (incl. Fitzroyomyces gen. nov.) on Cyperaceae, Murramarangomyces corymbiae (incl. Murramarangomyces gen. nov., Murramarangomycetaceae fam. nov. and Murramarangomycetales ord. nov.) on Corymbia maculata, Neoanungitea eucalypti (incl. Neoanungitea gen. nov.) on Eucalyptus obliqua, Neoconiothyrium persooniae (incl. Neoconiothyrium gen. nov.) on Persoonia laurina subsp. laurina, Neocrinula lambertiae (incl. Neocrinulaceae fam. nov.) on Lambertia sp., Ochroconis podocarpi on Podocarpus grayae, Paraphysalospora eucalypti (incl. Paraphysalospora gen. nov.) on Eucalyptus sieberi, Pararamichloridium livistonae (incl. Pararamichloridium gen. nov., Pararamichloridiaceae fam. nov. and Pararamichloridiales ord. nov.) on Livistona sp., Pestalotiopsis dianellae on Dianella sp., Phaeosphaeria gahniae on Gahnia aspera, Phlogicylindrium tereticornis on Eucalyptus tereticornis, Pleopassalora acaciae on Acacia obliquinervia, Pseudodactylaria xanthorrhoeae (incl. Pseudodactylaria gen. nov., Pseudodactylariaceae fam. nov. and Pseudodactylariales ord. nov.) on Xanthorrhoea sp., Pseudosporidesmium lambertiae (incl. Pseudosporidesmiaceae fam. nov.) on Lambertia formosa, Saccharata acaciae on Acacia sp., Saccharata epacridis on Epacris sp., Saccharata hakeigena on Hakea sericea, Seiridium persooniae on Persoonia sp., Semifissispora tooloomensis on Eucalyptus dunnii, Stagonospora lomandrae on Lomandra longifolia, Stagonospora victoriana on Poaceae, Subramaniomyces podocarpi on Podocarpus elatus, Sympoventuria melaleucae on Melaleuca sp., Sympoventuria regnans on Eucalyptus regnans, Trichomerium eucalypti on Eucalyptus tereticornis, Vermiculariopsiella eucalypticola on Eucalyptus dalrympleana, Verrucoconiothyrium acaciae on Acacia falciformis, Xenopassalora petrophiles (incl. Xenopassalora gen. nov.) on Petrophile sp., Zasmidium dasypogonis on Dasypogon sp., Zasmidium gahniicola on Gahnia sieberiana.Brazil: Achaetomium lippiae on Lippia gracilis, Cyathus isometricus on decaying wood, Geastrum caririense on soil, Lycoperdon demoulinii (incl. Lycoperdon subg. Arenicola) on soil, Megatomentella cristata (incl. Megatomentella gen. nov.) on unidentified plant, Mutinus verrucosus on soil, Paraopeba schefflerae (incl. Paraopeba gen. nov.) on Schefflera morototoni, Phyllosticta catimbauensis on Mandevilla catimbauensis, Pseudocercospora angularis on Prunus persica, Pseudophialophora sorghi on Sorghum bicolor, Spumula piptadeniae on Piptadenia paniculata.Bulgaria: Yarrowia parophonii from gut of Parophonus hirsutulus. Croatia: Pyrenopeziza velebitica on Lonicera borbasiana.Cyprus: Peziza halophila on coastal dunes. Czech Republic: Aspergillus contaminans from human fingernail. Ecuador: Cuphophyllus yacurensis on forest soil, Ganoderma podocarpense on fallen tree trunk. England: Pilidium anglicum (incl. Chaetomellales ord. nov.) on Eucalyptus sp. France: Planamyces parisiensis (incl. Planamyces gen. nov.) on wood inside a house. French Guiana: Lactifluus ceraceus on soil. Germany: Talaromyces musae on Musa sp. India: Hyalocladosporiella cannae on Canna indica, Nothophoma raii from soil. Italy: Setophaeosphaeria citri on Citrus reticulata, Yuccamyces citri on Citrus limon.Japan: Glutinomyces brunneus (incl. Glutinomyces gen. nov.) from roots of Quercus sp. Netherlands (all from soil): Collariella hilkhuijsenii, Fusarium petersiae, Gamsia kooimaniorum, Paracremonium binnewijzendii, Phaeoisaria annesophieae, Plectosphaerella niemeijerarum, Striaticonidium deklijnearum, Talaromyces annesophieae, Umbelopsis wiegerinckiae, Vandijckella johannae (incl. Vandijckella gen. nov. and Vandijckellaceae fam. nov.), Verhulstia trisororum (incl. Verhulstia gen. nov.). New Zealand: Lasiosphaeria similisorbina on decorticated wood. Papua New Guinea: Pseudosubramaniomyces gen. nov. (based on Pseudosubramaniomyces fusisaprophyticus comb. nov.). Slovakia: Hemileucoglossum pusillum on soil. South Africa: Tygervalleyomyces podocarpi (incl. Tygervalleyomyces gen. nov.) on Podocarpus falcatus.Spain: Coniella heterospora from herbivorous dung, Hymenochaete macrochloae on Macrochloa tenacissima, Ramaria cistophila on shrubland of Cistus ladanifer.Thailand: Polycephalomyces phaothaiensis on Coleoptera larvae, buried in soil. Uruguay: Penicillium uruguayense from soil. Vietnam: Entoloma nigrovelutinum on forest soil, Volvariella morozovae on wood of unknown tree. Morphological and culture characteristics along with DNA barcodes are provided.

10.
Plant Dis ; 98(6): 849, 2014 Jun.
Article in English | MEDLINE | ID: mdl-30708661

ABSTRACT

Phoenix roebelenii (Arecaceae), known as dwarf date (tamareira-anã in Brazil), is a palm native to Southeast Asia and widely cultivated worldwide because of its ornamental value and ease of adaptation to a broad range of climates and soil types (4). In June 2012, some individuals were observed in a private garden in the municipality of Viçosa (state of Minas Gerais, Brazil) bearing numerous necrotic lesions on its leaves. Representative samples were taken, dried in a plant press, and brought to the laboratory for examination. A fungus was regularly associated with the leaf spots. Fungal structures were mounted in lactophenol and slides were examined under a microscope (Olympus BX 51). Spores were taken from sporulating colonies with a sterile fine needle and plated on PDA for isolation. A pure culture was deposited in the culture collection of the Universidade Federal de Viçosa (accession COAD1338). A dried herbarium sample was deposited in the local herbarium (VIC39741). The fungus had the following morphology: conidiophores grouped on sporodochia, cylindrical, 12 to 29 × 5 to 6 µm, dark brown; conidiogenous cells, terminal, proliferating percurrently (annellidic), 8 to 20 × 5 to 6 µm, pale to dark brown; conidia obclavate to subcylindrical, straight, 58 to 147 × 5 to 6 µm, 6 to 16 septate, hila thickened and darkened with a thin-walled projecting papilla, dark brown, and verrucose. The morphology of the Brazilian collections agrees well with the description of Stigmina palmivora (2), a species known to cause leaf spots on P. roebelenii in the United States (Florida) and Japan (3). Pathogenicity was demonstrated through inoculation of leaves of healthy plants by placing 6 mm diameter cuture disks of COAD1338 on the leaf surface followed by incubation in a moist chamber for 48 h and then transferred to a greenhouse bench at 21 ± 3°C. Typical leaf spots were observed 15 days after inoculation. DNA was extracted from the isolate growing in pure culture and ITS and LSU sequences were generated and deposited in GenBank under the accession numbers KF656785 and KF656786, respectively. These were compared by BLASTn with other entries in GenBank, and the closest match for each region were Mycosphaerella colombiensis strain X215 and M. irregulariamosa strain CPC 1362 (EU514231, GU2114441) with 93% of nucleotide homology (over 100% query coverage) for ITS and 98% of nucleotide homology (over 100% query coverage) for LSU. There are no sequences for S. palmivora deposited in public databases for comparison, but for Stigmina platani, the type species in this genus, 86% and 96% nucleotide homology for ITS and LSU with S. palmivora were found. The genus Stigmina is regarded as being polyphyletic (1) and this is probably reflected by these low homology levels found in the BLASTn search. To our knowledge, this is the first report of Stigmina palmivora in Brazil. References: (1) P. W. Crous et al. Stud. Mycol. 75:37, 2012. (2) M. B. Ellis. Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew, UK, 1971. (3) D. F. Farr and A. Y. Rossman. Fungal Databases. Syst. Mycol. Microbiol. Lab. ARS, USDA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ , 2013. (4) H. Lorenzi et al. Palmeira no Brasil: Exóticas e Nativas, 2nd ed. Editora Plantarum, Nova Odessa, Brazil, 2005.

11.
Plant Dis ; 98(7): 1007, 2014 Jul.
Article in English | MEDLINE | ID: mdl-30708853

ABSTRACT

Sinapis alba (Brassicaceae), white mustard, is broadly cultivated for its seed used as component of table mustard (4). In June 2013, a group of diseased S. alba were observed in a vegetable garden on the campus of the Universidade Federal de Viçosa (municipality of Viçosa, state of Minas Gerais, Brazil). Foliage of diseased plants showed numerous chlorotic areas that developed into severe leaf blight with abundant downy mildew growth abaxially. A dried representative specimen has been deposited in the herbarium at the Universidade Federal de Viçosa (accession no. VIC 39743). The fungus had the following morphology: Sporangiophores arborescent, dichotomously branched, 540 to 840 × 8 to 10 µm hyaline, smooth, branches 105 to 210 µm long; esterigmata subacutate and curved, in pairs, 15 to 42 µm long; sporangia globose, 18 to 24 × 15 to 18 µm, hyaline, smooth. DNA was extracted using a Wizard Promega purification kit. The cytochrome oxidase subunit II (COX2) region was amplified with COX2f and COX2r primers (3). The sequence has been deposited in GenBank (Accession No. KJ396953). DNA sequences representing morphologically similar taxa were downloaded from GenBank nucleotide database, aligned in MEGA 5, and analyzed using Bayesian inference and Markov chain Monte Carlo simulation implemented in MrBayes 3.0 with five repetitions. A sequence of Albugo candida was used as outgroup in the analysis. The morphological characteristics places the fungus on S. alba in the complex of species of Pernosporaceae that attack the Brassicaceae. These are notoriously difficult to discriminate by morphology but our COX2-based phylogenetic analysis places it in Hyaloperonospora lunariae (1). This species was previously only known to cause downy mildew on other species of Brassicaceae (Lunaria annua and Erucastrum nasturtiifolium) in Europe (2). To our knowledge, this is the first report of this pathogen-host association in the world. References: (1) O. Constantinescu and J. Fatehi. Nova Hediwigia 74:291, 2002 (2) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory. Online publication. ARS, USDA, 2013. (3) D. S. S. Hudspeth et al. Mycologia 92:674, 2000. (4) B. B. Simpson and M. C. Ogorzaly. Econonic Botany. McGraw Hill, San Diego, CA, 2001.

12.
Cytotherapy ; 10(4): 376-89, 2008.
Article in English | MEDLINE | ID: mdl-18574770

ABSTRACT

BACKGROUND: Current efforts to direct differentiation of human embryonic stem cells (hESC) into a particular cell lineage usually lead to a heterogeneous cell population with only a fraction of the desired cell type present. We show the generation of an essentially pure population of human cardiomyocytes from hESC using lineage selection. METHODS: A construct comprising the murine alpha-myosin heavy chain (alpha-MHC) promoter driving the neomycin-resistance gene was introduced into hES3 cells to generate stable transgenic lines. Transgenic hESC lines were differentiated into cardiomyocytes and subjected to G418 selection. Both G418-selected and non-selected cardiomyocytes were characterized by immunocytochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. The teratoma-forming potential of differentiated cells was assessed by injection of about 2 million cells into the hind limb muscle of SCID mice. Results After cardiac differentiation and antibiotic selection in a suspension culture process, more than 99% of the transgenic cells showed immunoreactivity to alpha-MHC and alpha-actinin; this enrichment efficiency was observed for independent transgenic cell lines. Quantitative RT-PCR analysis revealed high levels of enrichment for cardiac-specific messages in the selected population. Importantly, injection of selected cells into six SCID mice resulted in no apparent teratoma formation, in contrast to differentiated but non-selected controls. DISCUSSION: Our results represent a significant step toward scalable production of pure human cardiomyocytes from stable, expandable hESC lines that will facilitate the development of cell therapies, safety pharmacology and drug discovery.


Subject(s)
Cell Lineage , Embryonic Stem Cells , Myocytes, Cardiac , Animals , Cell Culture Techniques , Cell Differentiation , Cell Line , Electrophysiology , Embryonic Stem Cells/cytology , Embryonic Stem Cells/physiology , Hindlimb/pathology , Humans , Mice , Mice, SCID , Mice, Transgenic , Myocytes, Cardiac/cytology , Myocytes, Cardiac/physiology , Stem Cell Transplantation , Teratoma
13.
Organogenesis ; 2(1): 22-7, 2005 Jan.
Article in English | MEDLINE | ID: mdl-19521525

ABSTRACT

Neurogenin 3 (ngn3) is a basic helix loop helix transcription factor that is transiently expressed in the developing mouse pancreas with peak expression around E15. In mice lacking the ngn3 gene the endocrine cells of the pancreas fail to develop suggesting that the ngn3-positive cell may represent a progenitor cell for the endocrine pancreas. In order to purify and characterize this cell in detail we have generated a transgenic mouse, in which the ngn3 promoter drives expression of enhanced green fluorescent protein (EGFP). In the E15.5 embryo EGFP was expressed in the dorsal and ventral pancreas, the duodenum, and lower intestine as well as in the brain. This pattern of expression was in keeping with the known expression profile of the endogenous ngn3 gene. Within the pancreas EGFP was localized in close proximity to cells that stained positive for ngn3, insulin, and glucagon, but was absent from regions of the pancreas that stained positive for amylase. EGFP was also present in the pancreas at E18.5, although there was no detectable expression of ngn3. At this stage EGFP did not colocalize with any of the hormones or exocrine markers. EGFP(+) cells were FACS purified (96%) from the E15 pancreas yielding approximately 10,000 cells or 1.6% of the total pancreatic cells from one litter. RT/PCR analysis confirmed that the purified cells expressed EGFP, ngn3, insulin, glucagon, somatostatin and pancreatic polypeptide. The ability to purify ngn3(+) cells provides an invaluable source of material for charactering in detail their properties.

14.
Qual Saf Health Care ; 13(6): 461-6, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15576709

ABSTRACT

The medical consultation is best understood as a two-way social interaction involving interactive decision making. Game theory--a theory based on assumptions of rational choice and focusing on interactive decision making--has the potential to provide models of the consultation that can be used to generate empirically testable predictions about the factors that promote quality of care. Three different game structures--the Prisoner's Dilemma game, the Assurance game, and the Centipede game--all provide insights into the possible underlying dynamics of the doctor-patient interaction. Further empirical work is needed to uncover the underlying game structures that occur most commonly in medical consultations. Game theory has the potential to provide a new conceptual and theoretical basis for future empirical work on the interaction between doctors and their patients.


Subject(s)
Game Theory , Models, Theoretical , Referral and Consultation , Humans , Quality of Health Care
15.
Ann Acad Med Singap ; 33(1): 121-7, 2004 Jan.
Article in English | MEDLINE | ID: mdl-15008577

ABSTRACT

The announcement of the birth of Dolly the sheep, the world's first adult cell somatic mammalian clone, in February 1997, caused excitement and concern in equal measure. Since then, the technique has been extended to 7 further species and has been refined to allow the introduction of new genes into clones as well as modification of existing ones. Health problems continue to be an issue of concern and the technique remains highly inefficient. This inefficiency is due to reprogramming difficulties in the donor nuclei, a problem that confounds immediate solution but one that is fuelling a lot of interesting basic research. Cloning could also be used to make embryonic stem (ES) cell lines from healthy cells taken from sick patients and after further manipulation, tissue made from these ES cells could be used to replace damaged tissue. Proof of principle of this concept, otherwise known as therapeutic cloning, has been obtained in mice, but its implementation in humans is a long way off.


Subject(s)
Cloning, Organism , Animals , Cells, Cultured , Humans , Sheep , Stem Cells
16.
Nat Biotechnol ; 19(10): 974-7, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11581666

ABSTRACT

The increasing use of peptides as pharmaceutical agents, especially in the antiviral and anti-infective therapeutic areas, requires cost-effective production on a large scale. Many peptides need carboxy amidation for full activity or prolonged bioavailability. However, this modification is not possible in prokaryotes and must be done using recombinant enzymes or by expression in transgenic milk. Methods employing recombinant enzymes are appropriate for small-scale production, whereas transgenic milk expression is suitable for making complex disulfide-containing peptides required in large quantity. Here we describe a method for making amidated peptides using a modified self-cleaving vacuolar membrane ATPase (VMA) intein expression system. This system is suitable for making amidated peptides at a laboratory scale using readily available constructs and reagents. Further improvements are possible, such as reducing the size of the intein to improve the peptide yields (the VMA intein comprises 454 amino acids) and, if necessary, secreting the fusion protein to ensure correct N-terminal processing to the peptide. With such developments, this method could form the basis of a large-scale cost-effective system for the bulk production of amidated peptides without the use of recombinant enzymes or the need to cleave fusion proteins.


Subject(s)
Cloning, Molecular/methods , Escherichia coli/genetics , Peptides/genetics , Proton-Translocating ATPases/genetics , Recombinant Fusion Proteins/metabolism , Vacuolar Proton-Translocating ATPases , Amides/metabolism , Amino Acid Sequence , Genetic Vectors , Molecular Sequence Data , Peptides/metabolism , Protein Processing, Post-Translational , Recombinant Fusion Proteins/genetics
17.
Respir Physiol ; 127(2-3): 157-72, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11504587

ABSTRACT

Opioid modulation of breathing during postnatal development through to the adult was investigated in the rat. Respiratory frequency, tidal volume and minute volume were recorded in unanesthetized, unrestrained rat pups and adults using barometric plethysmography. Subjects were administered the highly selective mu opioid agonists dermorphin and fentanyl. Fentanyl, which readily crosses the blood-brain barrier, was included to ensure that developmental changes in blood-brain barrier restrictions did not mask some of the dermorphin effects in older neonates. Drugs were administered subcutaneously in neonates and adults, although dermorphin was given by intracerebroventricular route only in adults. In neonates, mu agonist administration caused a gasping-like pattern of breathing, characterized by a marked fall in frequency and a smaller increase in tidal volume. The gasping response was prevented by pre-treatment with the long-acting mu1 antagonist naloxonazine (NALZ). In the presence of NALZ, mu agonists elicited only a small, but significant, reduction in tidal volume. Both dermorphin and fentanyl showed more potent activity in younger pups than in older pups, possibly in the case of dermorphin because of developmental maturation of blood-brain barrier function. In adults, fentanyl and dermorphin both caused a reduction in frequency and minute volume. The response of adults to fentanyl, but not dermorphin, was prevented by NALZ. These results suggest that both mu1 and mu2 receptors contribute to opioid-induced respiratory depression during neonatal and adult life.


Subject(s)
Lung/physiology , Naloxone/analogs & derivatives , Receptors, Opioid, mu/physiology , Respiratory Mechanics/physiology , Age Factors , Analgesics, Opioid/pharmacology , Animals , Animals, Newborn , Female , Fentanyl/pharmacology , Male , Naloxone/pharmacology , Oligopeptides/pharmacology , Opioid Peptides , Rats , Rats, Wistar , Receptors, Opioid, mu/agonists , Receptors, Opioid, mu/antagonists & inhibitors , Respiratory Mechanics/drug effects , Tidal Volume/drug effects , Tidal Volume/physiology
19.
Nature ; 407(6800): 86-90, 2000 Sep 07.
Article in English | MEDLINE | ID: mdl-10993078

ABSTRACT

Since the first report of live mammals produced by nuclear transfer from a cultured differentiated cell population in 1995 (ref. 1), successful development has been obtained in sheep, cattle, mice and goats using a variety of somatic cell types as nuclear donors. The methodology used for embryo reconstruction in each of these species is essentially similar: diploid donor nuclei have been transplanted into enucleated MII oocytes that are activated on, or after transfer. In sheep and goat pre-activated oocytes have also proved successful as cytoplast recipients. The reconstructed embryos are then cultured and selected embryos transferred to surrogate recipients for development to term. In pigs, nuclear transfer has been significantly less successful; a single piglet was reported after transfer of a blastomere nucleus from a four-cell embryo to an enucleated oocyte; however, no live offspring were obtained in studies using somatic cells such as diploid or mitotic fetal fibroblasts as nuclear donors. The development of embryos reconstructed by nuclear transfer is dependent upon a range of factors. Here we investigate some of these factors and report the successful production of cloned piglets from a cultured adult somatic cell population using a new nuclear transfer procedure.


Subject(s)
Cloning, Organism , Nuclear Transfer Techniques , Swine , Animals , Cell Cycle , Cells, Cultured , Cloning, Organism/methods , Female , Microsatellite Repeats , Oocytes
20.
Nature ; 405(6790): 1066-9, 2000 Jun 29.
Article in English | MEDLINE | ID: mdl-10890449

ABSTRACT

It is over a decade since the first demonstration that mouse embryonic stem cells could be used to transfer a predetermined genetic modification to a whole animal. The extension of this technique to other mammalian species, particularly livestock, might bring numerous biomedical benefits, for example, ablation of xenoreactive transplantation antigens, inactivation of genes responsible for neuropathogenic disease and precise placement of transgenes designed to produce proteins for human therapy. Gene targeting has not yet been achieved in mammals other than mice, however, because functional embryonic stem cells have not been derived. Nuclear transfer from cultured somatic cells provides an alternative means of cell-mediated transgenesis. Here we describe efficient and reproducible gene targeting in fetal fibroblasts to place a therapeutic transgene at the ovine alpha1(I) procollagen (COL1A1) locus and the production of live sheep by nuclear transfer.


Subject(s)
Gene Targeting , Nuclear Transfer Techniques , Procollagen/genetics , Sheep/genetics , Animals , Blotting, Southern , Cell Line , Female , Fibroblasts/cytology , Male , Sheep/embryology , Transfection , Transgenes
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