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1.
Persoonia ; 51: 257-279, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38665980

RESUMO

The genus Podaxis was first described from India by Linnaeus in 1771, but several revisions of the genus have left the taxonomy unclear. Forty-four Podaxis species names and nine intraspecific varieties are currently accepted, but most fungarium specimens are labelled Podaxis pistillaris. Recent molecular analyses based on barcoding genes suggest that the genus comprises several species, but their status is largely unresolved. Here we obtained basidiospores and photographs from 166 fungarium specimens from around the world and generated a phylogeny based on rDNA internal transcribed spacer ITS1,5.8S and ITS2 (ITS), and a phylogenomic analysis of 3 839 BUSCO genes from low-coverage genomes for a subset of the specimens. Combining phylogenetics, phylogenomics, morphology, ecology, and geographical distribution, spanning 250 years of collections, we propose that the genus includes at least 16 unambiguous species. Based on 10 type specimens (holotype, paratype, and syntype), four recorded species were confirmed, P. carcinomalis, P. deflersii, P. emerici, and P. farlowii. Comparing phylogenetic analysis with described species, including morphology, ecology, and distribution, we resurrected P. termitophilus and designated neotypes, epitypes, or lectotypes for five previously described species, P. aegyptiacus, P. africana, P. beringamensis, P. calyptratus, and P. perraldieri. Lastly, based on phylogenies and morphology of type material, we synonymized three reported species, P. algericus, P. arabicus, and P. rugospora with P. pistillaris, and described five new species that we named P. desolatus, P. inyoensis, P. mareebaensis, P. namaquensis, and P. namibensis. Citation: Li GS, Leal-Dutra CA, Cuesta-Maté A, et al. 2023. Resolution of eleven reported and five novel Podaxis species based on ITS phylogeny, phylogenomics, morphology, ecology, and geographic distribution. Persoonia 51: 257-279. doi: 10.3767/persoonia.2023.51.07.

2.
Radiat Prot Dosimetry ; 193(1): 24-36, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33693932

RESUMO

The study aimed to implement realistic source models of a computed tomography (CT) scanner and Monte Carlo simulations to actual patient data and to calculate patient-specific organ and effective dose estimates for patients undergoing dynamic CT myocardial perfusion examinations. Source models including bowtie filter, tube output and x-ray spectra were determined for a dual-source Siemens Somatom Definition Flash scanner. Twenty CT angiography patient datasets were merged with a scaled International Commission on Radiological Protection (ICRP) 110 voxel phantom. Dose simulations were conducted with ImpactMC software. Effective dose estimates varied from 5.0 to 14.6 mSv for the 80 kV spectrum and from 8.9 to 24.7 mSv for the 100 kV spectrum. Significant differences in organ doses and effective doses between patients emphasise the need to use actual patient data merged with matched anthropomorphic anatomy in the dose simulations to achieve a reasonable level of accuracy in the dose estimation procedure.


Assuntos
Tomografia Computadorizada por Raios X , Humanos , Método de Monte Carlo , Perfusão , Imagens de Fantasmas , Doses de Radiação
3.
Phys Med Biol ; 64(7): 075009, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30856614

RESUMO

Personalized dosimetry in computed tomography (CT) can be realized by a full Monte Carlo (MC) simulation of the scan procedure. Essential input data needed for the simulation are appropriate CT x-ray source models and a model of the patient's body which is based on the CT image. The purpose of this work is to develop comprehensive procedures for the determination of CT x-ray source models and their verification by comparison of calculated and measured dose distributions in physical phantoms. Mobile equipment together with customized software was developed and used for non-invasive determination of equivalent source models of CT scanners under clinical conditions. Standard and physical anthropomorphic CT dose phantoms equipped with real-time CT dose probes at five representative positions were scanned. The accumulated dose was measured during the scan at the five positions. ImpactMC, an MC-based CT dose software program, was used to simulate the scan. The necessary inputs were obtained from the scan parameters, from the equivalent source models and from the material-segmented CT images of the phantoms. 3D dose distributions in the phantoms were simulated and the dose values calculated at the five positions inside the phantom were compared to measured dose values. Initial results were obtained by means of a General Electric Optima CT 660 and a Toshiba (Canon) Aquilion ONE. In general, the measured and calculated dose values were within relative uncertainties that had been estimated to be less than 10%. The procedures developed were found to be viable and rapid. The procedures are applicable to any scanner type under clinical conditions without making use of the service mode with stationary x-ray tube position. Results show that the procedures are well suited for determining and verifying the equivalent source models needed for personalized CT dosimetry based on post-scan MC calculations.


Assuntos
Algoritmos , Imagens de Fantasmas , Medicina de Precisão , Radiometria/métodos , Tomógrafos Computadorizados , Tomografia Computadorizada por Raios X/métodos , Humanos , Método de Monte Carlo , Doses de Radiação , Software
4.
Rev Sci Instrum ; 86(11): 115104, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26628169

RESUMO

The separation of krypton and xenon is of particular importance for the field of direct dark matter search with liquid xenon detectors. The intrinsic contamination of the xenon with radioactive (85)Kr makes a significant background for these kinds of low count-rate experiments and has to be removed beforehand. This can be achieved by cryogenic distillation, a technique widely used in industry, using the different vapor pressures of krypton and xenon. In this paper, we present an investigation on the separation performance of a single stage distillation system using a radioactive (83m)Kr-tracer method. The separation characteristics under different operation conditions are determined for very low concentrations of krypton in xenon at the level of (83m)Kr/Xe = 1.9 ⋅ 10(-15), demonstrating, that cryogenic distillation in this regime is working. The observed separation is in agreement with the expectation from the different volatilities of krypton and xenon. This cryogenic distillation station is the first step on the way to a multi-stage cryogenic distillation column for the next generation of direct dark matter experiment XENON1T.

5.
Mol Ecol ; 10(8): 2089-93, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11555252

RESUMO

The mitochondrial ribosomal large subunit (Ls) DNA was used to identify the orchid mycorrhizal fungi found in roots of Dactylorhiza majalis. The gene was amplified using DNA extracted from single pelotons obtained from fresh and silica gel dried roots. Furthermore, sequencing a variety of well-characterized orchid isolates expanded the fungal database of the mitochondrial ribosomal LsDNA. Polymerase chain reaction product length variants present in D. majalis were sequenced and identified using the expanded database. These analyses revealed two different peloton-forming fungi in samples from D. majalis, which sometimes occurred together as a single two-taxa peloton within the same cortex cell. The first taxon belonged to the genus Tulasnella and the second taxon was distantly related to Laccaria.


Assuntos
Basidiomycota/classificação , Basidiomycota/genética , DNA Mitocondrial/genética , Orchidaceae/microbiologia , Raízes de Plantas/microbiologia , DNA Fúngico/análise , DNA Fúngico/genética , DNA Mitocondrial/análise , Proteínas Fúngicas/genética , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proteínas Ribossômicas/genética
6.
Vox Sang ; 80(3): 170-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11449957

RESUMO

BACKGROUND AND OBJECTIVES: Poor prognosis after resection of primary colorectal cancer may be related to the combination of perioperative blood transfusion and subsequent development of infectious complications. White blood cell--and platelet-derived cancer growth substances, including vascular endothelial growth factor (VEGF), may be involved in this process. Therefore, we studied the in vitro release of VEGF from white blood cells and platelets stimulated by bacterial antigens and supernatants from stored red cell components. MATERIALS AND METHODS: Eight units of whole blood (WB) and eight units of buffy-coat-depleted red cell (SAGM) blood were donated by healthy blood donors. Subsequently, half of every unit was leucocyte depleted by filtration, and all 32 half-units were stored under standard conditions for 35 days. Just after storage, and on days 7, 21 and 35 during storage, aliquots of the supernatants were removed from the units and frozen at -80 degrees C. WB from other healthy donors was stimulated for 2 h with sodium chloride (controls), with Escherichia coli lipopolysaccharide (LPS) alone, or with LPS plus supernatants from the non-filtered or prestorage leucofiltered WB units (diluted 1:10), or from non-filtered or prestorage leucofiltered SAGM blood units (diluted 1:20) stored for 0, 7, 21, or 35 days, respectively. Similar assays were performed using Staphylococcus aureus-derived protein A as a stimulatory antigen. The concentration of VEGF was determined in supernatants from stored blood and in assay supernatants by using enzyme-linked immunosorbent assay (ELISA). RESULTS: The concentration of VEGF increased significantly (P < 0.0001) in a storage time-dependent manner in non-filtered WB and SAGM blood, while the increase was abrogated by prestorage leucofiltration. The supernatant concentration of VEGF was significantly increased in LPS-stimulated (P = 0.002) and in protein A-stimulated (P < 0.0001) assays compared with controls. Addition of supernatants from stored, non-filtered WB or SAGM significantly increased the assay supernatant VEGF concentration storage-time dependently (P = 0.006) in LPS assays. In protein A assays, only supernatants from non-filtered WB significantly increased the assay supernatant VEGF concentration storage-time dependently (P = 0.022). This additional effect by supernatants from stored blood components was not observed with prestorage leucofiltered blood. CONCLUSIONS: Extracellular VEGF may accumulate in non-filtered red cell components, but this can be prevented by prestorage leucocyte depletion using filtration. In addition, bacterial antigens appear to induce release of VEGF from white blood cells and platelets. Addition of supernatants from stored, non-filtered WB or SAGM blood may increase the VEGF levels in a storage time-dependent manner, while prestorage leucofiltration may prevent further increase by supernatants.


Assuntos
Antígenos de Bactérias/farmacologia , Fatores de Crescimento Endotelial/metabolismo , Leucócitos/metabolismo , Lipopolissacarídeos/farmacologia , Linfocinas/metabolismo , Proteína Estafilocócica A/farmacologia , Adulto , Remoção de Componentes Sanguíneos , Plaquetas/metabolismo , Preservação de Sangue , Meios de Cultivo Condicionados/farmacologia , Grânulos Citoplasmáticos/metabolismo , Ensaio de Imunoadsorção Enzimática , Eritrócitos , Exocitose/efeitos dos fármacos , Filtração , Humanos , Leucócitos/efeitos dos fármacos , Reação Transfusional , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
7.
Phytopathology ; 91(12): 1231-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18943339

RESUMO

ABSTRACT Fusarium wilt of cotton is a serious fungal disease responsible for significant yield losses throughout the world. Evolution of the causal organism Fusarium oxysporum f. sp. vasinfectum, including the eight races described for this specialized form, was studied using multigene genealogies. Partial sequences of translation elongation factor (EF-1alpha), nitrate reductase (NIR), phosphate permase (PHO), and the mitochondrial small subunit (mtSSU) rDNA were sequenced in 28 isolates of F. oxysporum f. sp. vasinfectum selected to represent the global genetic diversity of this forma specialis. Results of a Wilcoxon Signed-Ranks Templeton test indicated that sequences of the four genes could be combined. In addition, using combined data from EF-1alpha and mtSSU rDNA, the phylogenetic origin of F. oxysporum f. sp. vasinfectum within the F. oxysporum complex was evaluated by the Kishino-Hasegawa likelihood test. Results of this test indicated the eight races of F. oxysporum f. sp. vasinfectum appeared to be nonmonophyletic, having at least two independent, or polyphyletic, evolutionary origins. Races 3 and 5 formed a strongly supported clade separate from the other six races. The combined EF-1alpha, NIR, PHO, and mtSSU rDNA sequence data from the 28 isolates of F. oxysporum f. sp. vasinfectum recovered four lineages that correlated with differences in virulence and geographic origin: lineage I contained race 3, mostly from Egypt, and race 5 from Sudan; lineage II contained races 1, 2, and 6 from North and South America and Africa; lineage III contained race 8 from China; and lineage IV contained isolates of races 4 and 7 from India and China, respectively.

8.
Fungal Genet Biol ; 24(3): 325-34, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9756713

RESUMO

We sequenced the nuclear small subunit of ribosomal DNA (SSU rDNA) from seven species within the insect-pathogenic order Entomophthorales. These sequences were aligned with other published SSU rDNA sequences and phylogenies were inferred using phenetic and cladistic methods. Based on three different phylogenetic methods the Entomophthorales (excluding Basidiobolus ranarum) is monophyletic; B. ranarum was more closely related to chytrids from Chytridiales and Neocallimasticales than to Entomophthorales, as was proposed by Nagahama et al. (Mycologia 87: 203-209, 1995). Nuclear characters (large nuclei containing conspicuous condensed chromatin and lack of a prominent nucleolus) were of predictive value for the monophyly of the family Entomophthoraceae. Conidial characters separate the Entomophthoraceae, which only includes obligate pathogens, into at least two lineages: one lineage with uninucleate conidia and another with multinucleate conidia. The two species of Conidiobolus studied were paraphyletic in our analyses and only distantly related to each other. This information may prove to be important in the use of these fungi as biocontrol agents.


Assuntos
DNA Ribossômico/genética , Entomophthorales/classificação , Entomophthorales/genética , Insetos/microbiologia , Filogenia , Animais , Sequência de Bases , Primers do DNA , DNA Fúngico/genética , DNA Ribossômico/química , Evolução Molecular
9.
Phytopathology ; 88(9): 992-6, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18944878

RESUMO

ABSTRACT To describe the disease cycle of the root pathogen Aphanomyces euteiches, enzymatic activity in the mycelium was compared with the development of oospores in pea roots. Plants were inoculated with two zoospore concentrations to achieve different disease levels. Hyphae were stained for fungal alkaline phosphatase activity in the roots. Additionally, enzyme activity was measured after electrophoresis of an A. euteiches-specific glucose-6-phosphate isozyme. Development of oospores in the roots was measured after staining the oospores with trypan blue. In plants inoculated with the higher zoospore concentration, the enzymatic activity of the pathogen mycelium peaked 10 to 14 days after inoculation, when oospore formation was initiated. Oospore formation was associated with a gradual increase in disease symptoms. At the last harvest, plants inoculated with the higher zoospore concentration had died. In these plants, oospores were found in 90% of the root length, while the enzymatic activity of the mycelium was low. This suggests that the pathogen mycelium is only active on living plants and does not grow saprophytically on dead plant material.

10.
New Phytol ; 132(1): 127-133, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33863061

RESUMO

Short-term effects of benomyl on the arbuscular mycorrhizal fungus Glomus caledonium (Nicol. & Gerd.) Trappe and Gerdeman associated with Cucumis sativus L. were studied by measuring effects on fungal P transport and on fungal alkaline phosphatase activity. Mycorrhizal plants were grown in three compartment systems where nylon mesh was used to separate n root-free hyphal compartment (HC) and a root + hyphal compartment(RHC) from The main root compartment (RC). Non-mycorrhizal control plants were grown in similar growth units. After 6 wk benomyl was applied to the plants in three ways: as soil drenches to RHC or HC, or as u spray to the leaves. Benomyl was added in three concentrations. Equal amounts of 32 P and 33 P were added to the HC and to the RHC respectively, immediately after the application of benomyl. Plants were harvested 4-6 d later. Hyphal transport of 32 P from the HC was inhibited when benomyl was applied to the HC at 10 µg g-1 soil, whereas the uptake of 32 P from RHC I roots + hyphae) was reduced only at the highest dose of application to the RHC (100 µ g g-1 soil). In contrast to the marked reduction of benomyl on fungal P transport, the activity of fungal alkaline phosphatase inside the roots was unaffected by benomyl.

11.
Acta Orthop Scand ; 57(2): 154-7, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3705942

RESUMO

Functional ability and social dependence were investigated by personal interview of 107 lower limb amputees surviving 1-5 years postoperatively. Among eight independent variables studied by multiple regression analysis, increased age was associated unfavorably with physical ability and social dependence. Independence from social provisions preoperatively showed favorable relationships with functional capacity and postoperative dependence. Above-knee or bilateral amputation and postoperative pain were associated with reduced functional ability, but not with social dependence. No significant association was found with cause of operation or sex of the amputees. The importance of proper prosthetic fitting and pain control is emphasized.


Assuntos
Amputação Cirúrgica/reabilitação , Perna (Membro)/cirurgia , Ajustamento Social , Atividades Cotidianas , Adulto , Fatores Etários , Idoso , Amputação Cirúrgica/psicologia , Membros Artificiais , Avaliação da Deficiência , Feminino , Humanos , Locomoção , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/etiologia , Membro Fantasma
13.
Injury ; 13(4): 307-14, 1982 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7061139

RESUMO

Ninety-six displaced fractures of the shaft of the tibia in a series of 162 consecutive fractures were treated by AO internal fixation. Forty per cent were open fractures, of which 93 per cent received prophylactic treatment with antibiotics at the time of admission. The average time between the accident and the operation was 10 hours in closed fractures and 5 hours in open fractures. All cases were operated on by senior surgeons. The infection rate was 5.3 per cent in closed fractures, and 0 in open fractures. The average stay in hospital was 13 days. More than 90 per cent returned to work within 6 months after the accident. No case of pseudarthrosis or re-fracture was seen. The median time to final review was 36 months. Rigid internal fixation is advocated for all displaced fractures of the shaft of the tibia and is advocated as an urgent procedure especially in open fractures, and should be performed by experienced surgeons only. Rigid internal fixation appears to provide effective prophylaxis against secondary soft-tissue damage and limits the consequences of the initial soft-tissue damage.


Assuntos
Fixação Interna de Fraturas/métodos , Fraturas da Tíbia/cirurgia , Adulto , Idoso , Estudos de Avaliação como Assunto , Feminino , Seguimentos , Fraturas Fechadas/cirurgia , Fraturas Expostas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Fatores de Tempo
14.
Acta Orthop Scand ; 48(4): 400-4, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-411321

RESUMO

Seventy patients, representing all the survivors from a group of 117 consecutive Moore arthroplasties, were examined 2 years after the operation. A high incidence of para-articular ossification was observed. The ossification was associated with impaired function of the hip joint. The separation of periost and fascia from the greater trochanter in McFarland's approach may be responsible for the high incidence of bone formation. This theory is compatible with experimental evidence.


Assuntos
Articulação do Quadril/cirurgia , Prótese Articular/efeitos adversos , Ossificação Heterotópica/etiologia , Idoso , Feminino , Fraturas do Colo Femoral/cirurgia , Seguimentos , Humanos , Prótese Articular/métodos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade
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