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1.
Fungal Syst Evol ; 13: 111-122, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39129970

RESUMO

The genus Phytophthora contains many destructive and globally important plant pathogens. In the last decade, targeted sampling efforts have resulted in a dramatic increase in the number of known species, as well as a better understanding of their global distribution. Routine activities undertaken in botanical gardens, combined with great numbers of local and international visitors, place botanical gardens at risk to the accidental introduction and establishment of pathogens such as Phytophthora spp. In this study, the occurrence of Phytophthora was investigated in two botanical gardens in the KwaZulu-Natal Province of South Africa. Symptomatic collar and stem tissues were collected, and root and rhizosphere soil samples were taken from trees exhibiting symptoms of decline. Standard baiting techniques and direct plating of symptomatic tissues revealed the presence of seven species of Phytophthora residing in four phylogenetic clades. Five of these species, P. cinnamomi, P. citrophthora, P. multivora, P. parvispora and the informally designated taxon Phytophthora sp. stellaris were known to be present in South Africa and P. aquimorbida was recorded for the first time. Of these, P. citrophthora represented a novel host-pathogen association causing bleeding cankers on indigenous Celtis africana. A multilocus phylogenetic analysis based on ITS, ßtub, cox1 and hsp90 sequences showed the presence of an undescribed species belonging to the Phytophthora ITS Clade 5. This species is described here as Phytophthora mammiformis sp. nov. This study highlights the importance of monitoring botanical gardens for the detection and discovery of pathogens and emphasises their value as sites for the discovery of novel host-pathogen associations. Citation: Paap T, Balocchi F, Burgess TI, Bose T, Wingfield MJ (2024). A diverse range of Phytophthora species from botanical gardens in South Africa, including the novel Clade 5 species, Phytophthora mammiformis sp. nov. Fungal Systematics and Evolution 13: 111-122. doi: 10.3114/fuse.2024.13.05.

2.
Fungal Syst Evol ; 9: 1-9, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35978989

RESUMO

Black yeasts are a phylogenetically diverse group of ascomycetous fungi that may exist in both unicellular and mycelial morphs. This group of fungi contains numerous commercially significant species as well as others whose precise roles are unknown, such as endolichenic species. There is currently a paucity of data about endolichenic black yeast species. To bridge this gap, we surveyed China's Inner Mongolia Autonomous Region in July 2019. Several fungal species associated with diverse lichens were isolated during this survey. Among these were two isolates of a previously unknown species of oleaginous black yeast from Mycosphaerellales. Analyses of morphological and molecular data revealed that these two isolates were closely related to Xenodevriesia strelitziicola (Xenodevriesiaceae), although with significant differences. As a result, we established the genus Melanodevriesia gen. nov. to describe this previously unknown species, Melanodevriesia melanelixiae sp. nov. In addition, we used Transmission Electron Microscopy to visualise the intracellular oil bodies metabolised by this fungus in its unicellular state. The black yeast species identified in this study may have a wide range of commercial applications. More research is needed to determine the chemical composition of the microbial oil synthesized by this fungus and whether it has commercial value. Citation: Chang R, Cao W, Wang Y, Li S, Li X, Bose T, Si HL (2022). Melanodevriesia, a new genus of endolichenic oleaginous black yeast recovered from the Inner Mongolia Region of China. Fungal Systematics and Evolution 9: 1-9. doi: 10.3114/fuse.2022.09.01.

3.
Cell Death Dis ; 6: e1648, 2015 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-25695601

RESUMO

Ion channels are abundantly expressed in both excitable and non-excitable cells, thereby regulating the Ca(2+) influx and downstream signaling pathways of physiological processes. The immune system is specialized in the process of cancer cell recognition and elimination, and is regulated by different ion channels. In comparison with the immune cells, ion channels behave differently in cancer cells by making the tumor cells more hyperpolarized and influence cancer cell proliferation and metastasis. Therefore, ion channels comprise an important therapeutic target in anti-cancer treatment. In this review, we discuss the implication of ion channels in regulation of Ca(2+) homeostasis during the crosstalk between immune and cancer cell as well as their role in cancer progression.


Assuntos
Cálcio/metabolismo , Canais Iônicos/metabolismo , Neoplasias/metabolismo , Animais , Homeostase , Humanos , Transdução de Sinais/fisiologia
4.
Eur Cell Mater ; 27: 149-64; discussion 164-5, 2014 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-24554272

RESUMO

The successful vascularisation of complex tissue engineered constructs for bone regeneration is still a major challenge in the field of tissue engineering. In this context, co-culture systems of endothelial cells and osteoblasts represent a promising approach to advance the formation of a stable vasculature as well as an excellent in vitro model to identify factors that positively influence bone healing processes, including angiogenesis. Under physiological conditions, the activation phase of angiogenesis is mainly induced by hypoxia or inflammation. Inflammatory cells such as macrophages secrete proinflammatory cytokines and proangiogenic growth factors, finally leading to the formation of new blood vessels. The aim of this study was to investigate if macrophages might positively influence the formation of microvessel-like structures via inflammatory mechanisms in a co-culture system consisting of human outgrowth endothelial cells (OECs) and primary osteoblasts. Treatment of co-cultures with macrophages (induced from THP-1) resulted in a higher number of microvessel-like structures formed by OECs compared to the co-culture. This change correlated with a significantly higher concentration of the proangiogenic VEGF in cell culture supernatants of triple-cultures and was accompanied by an increase in the expression of different proinflammatory cytokines, such as IL-6, IL-8 and TNFα. In addition, the expression of E-selectin and ICAM-1, adhesion molecules which are strongly involved in the interaction between leukocytes and endothelial cells during the process of inflammation was also found to be higher in triple-cultures compared to the double co-cultures, documenting an ongoing proinflammatory stimulus. These results raise the possibility of actively using pro-inflammatory stimuli in a tissue engineering context to accelerate healing mechanisms.


Assuntos
Diferenciação Celular , Citocinas/farmacologia , Células Endoteliais/efeitos dos fármacos , Macrófagos/metabolismo , Neovascularização Fisiológica , Osteoblastos/efeitos dos fármacos , Regeneração Óssea , Osso e Ossos/irrigação sanguínea , Osso e Ossos/fisiologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Citocinas/metabolismo , Células Endoteliais/citologia , Humanos , Microvasos/citologia , Microvasos/fisiologia , Osteoblastos/citologia , Engenharia Tecidual
5.
Phys Rev Lett ; 110(1): 011801, 2013 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-23383778

RESUMO

We present a measurement of the time-integrated flavor-specific semileptonic charge asymmetry in the decays of B(s)(0) mesons that have undergone flavor mixing, a(sl)(s), using B(s)(0)(B(s)(0)) → D(s)(-/+) µ(±) X decays, with D(s)(-/+) → [symbol: see text]π(-/+) and [symbol: see text]→ K(+) K(-), using 10.4 fb(-1) of proton-antiproton collisions collected by the D0 detector during Run II at the Fermilab Tevatron Collider. A fit to the difference between the time-integrated D(s)(-) and D(s)(+) mass distributions of the B(s)(0) and B(s)(0) candidates yields the flavor-specific asymmetry a(sl)(s) = [-1.12 ± 0.74(stat) ± 0.17(syst)]%, which is the most precise measurement and in agreement with the standard model prediction.

6.
Phys Rev Lett ; 108(26): 261603, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-23004960

RESUMO

Using data collected with the D0 detector at the Fermilab Tevatron Collider, corresponding to 5.3 fb(-1) of integrated luminosity, we search for violation of Lorentz invariance by examining the tt[over ¯] production cross section in lepton+jets final states. We quantify this violation using the standard-model extension framework, which predicts a dependence of the tt[over ¯] production cross section on sidereal time as the orientation of the detector changes with the rotation of the Earth. Within this framework, we measure components of the matrices (c(Q))(µν33) and (c(U))(µν33) containing coefficients used to parametrize violation of Lorentz invariance in the top quark sector. Within uncertainties, these coefficients are found to be consistent with zero.

7.
Phys Rev Lett ; 109(12): 121803, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-23005939

RESUMO

We present a search for the standard model (SM) Higgs boson produced in association with a Z boson in 9.7 fb(-1) of pp collisions collected with the D0 detector at the Fermilab Tevatron Collider at √s = 1.96 TeV. Selected events contain one reconstructed Z→e(+)e(-) or Z→µ(+)µ(-) candidate and at least two jets, including at least one jet identified as likely to contain a b quark. To validate the search procedure, we also measure the cross section for ZZ production in the same final state. It is found to be consistent with its SM prediction. We set upper limits on the ZH production cross section times branching ratio for H→bb at the 95% C.L. for Higgs boson masses 90 ≤ M(H) ≤ 150 GeV. The observed (expected) limit for M(H) = 125 GeV is 7.1 (5.1) times the SM cross section.

8.
Phys Rev Lett ; 109(12): 121804, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-23005940

RESUMO

We present a search for the standard model Higgs boson in final states with a charged lepton (electron or muon), missing transverse energy, and two or three jets, at least one of which is identified as a b-quark jet. The search is primarily sensitive to WH→ℓνbb production and uses data corresponding to 9.7 fb(-1) of integrated luminosity collected with the D0 detector at the Fermilab Tevatron pp Collider at √s = 1.96 TeV. We observe agreement between the data and the expected background. For a Higgs boson mass of 125 GeV, we set a 95% C.L. upper limit on the production of a standard model Higgs boson of 5.2 × σ(SM), where σ(SM) is the standard model Higgs boson production cross section, while the expected limit is 4.7 × σ(SM).

9.
Phys Rev Lett ; 109(12): 121802, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-23005938

RESUMO

We present the results of the combination of searches for the standard model Higgs boson produced in association with a W or Z boson and decaying into bb using the data sample collected with the D0 detector in pp collisions at √s = 1.96 TeV at the Fermilab Tevatron Collider. We derive 95% C.L. upper limits on the Higgs boson cross section relative to the standard model prediction in the mass range 100 GeV ≤ M(H) ≤ 150 GeV, and we exclude Higgs bosons with masses smaller than 102 GeV at the 95% C.L. In the mass range 120 GeV ≤ M(H) ≤145 GeV, the data exhibit an excess above the background prediction with a global significance of 1.5 standard deviations, consistent with the expectation in the presence of a standard model Higgs boson.

10.
Phys Rev Lett ; 108(18): 181803, 2012 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-22681058

RESUMO

We study WW and WZ production with ℓνqq (ℓ=e,µ) final states using data collected by the D0 detector at the Fermilab Tevatron Collider corresponding to 4.3 fb(-1) of integrated luminosity from pp collisions at sqrt[s]=1.96 TeV. Assuming the ratio between the production cross sections σ(WW) and σ(WZ) as predicted by the standard model, we measure the total WV (V=W,Z) cross section to be σ(WV)=19.6(-3.0)(+3.2) pb and reject the background-only hypothesis at a level of 7.9 standard deviations. We also use b-jet discrimination to separate the WZ component from the dominant WW component. Simultaneously fitting WW and WZ contributions, we measure σ(WW)=15.9(-3.2)(+3.7) pb and σ(WZ)=3.3(-3.3)(+4.1) pb, which is consistent with the standard model predictions.

11.
Phys Rev Lett ; 108(15): 151804, 2012 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-22587244

RESUMO

We present a measurement of the W boson mass using data corresponding to 4.3 fb(-1) of integrated luminosity collected with the D0 detector during Run II at the Fermilab Tevatron pp collider. With a sample of 1,677,394 W → eν candidate events, we measure M(W) = 80.367 ± 0.026 GeV. This result is combined with an earlier D0 result determined using an independent Run II data sample, corresponding to 1 fb(-1) of integrated luminosity, to yield M(W) = 80.375 ± 0.023 GeV.

12.
Phys Rev Lett ; 108(13): 131802, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22540694

RESUMO

We present a search for Kaluza-Klein (KK) particles predicted by models with universal extra dimensions (UED) using a data set corresponding to an integrated luminosity of 7.3 fb(-1), collected by the D0 detector at a pp center-of-mass energy of 1.96 TeV. The decay chain of KK particles can lead to a final state with two muons of the same charge. This signature is used to set a lower limit on the compactification scale of R(-1)>260 GeV in a minimal UED model.

13.
Phys Rev Lett ; 108(3): 032004, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22400731

RESUMO

We present a measurement of the ratio of events with correlated t and t ̅t spins to the total number of t ̅t events. This ratio f is evaluated using a matrix-element-based approach in 729 t ̅t candidate events with a single lepton ℓ (electron or muon) and at least four jets. The analyzed p ̅p collisions data correspond to an integrated luminosity of 5.3 fb(-1) and were collected with the D0 detector at the Fermilab Tevatron collider operating at a center-of-mass energy √s=1.96 TeV. Combining this result with a recent measurement of f in dileptonic final states, we find f in agreement with the standard model. In addition, the combination provides evidence for the presence of spin correlation in t ̅t events with a significance of more than 3 standard deviations.

14.
Dentomaxillofac Radiol ; 40(5): 282-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21697153

RESUMO

OBJECTIVE: The aim of this study was to examine the clinical and radiographic presentation of fibrous dysplasia through a 13-year retrospective study in patients who reported to the outpatient unit of Government Dental College, Trivandrum. METHODS: The clinical file records and radiographs of the patients who reported to the outpatient clinic in the Department of Oral Medicine and Radiology were retrospectively reviewed for histopathologically diagnosed fibrous dysplasia. A detailed analysis of the clinical and radiographic features of the 24 cases retrieved was carried out. RESULTS: The male-to-female ratio of incidence was approximately 1:1. Most of the patients were in the second or third decade of life. Almost all the patients presented with a complaint of swelling on the side of the face. The mandible was more frequently involved than the maxilla. The most common radiographic pattern observed was the "ground-glass" appearance. Most of the patients exhibited expansion of the involved bone and loss of lamina dura of associated teeth. CONCLUSION: The awareness of protean features of fibrous dysplasia evident through this study is essential in the accurate diagnosis and proper treatment planning of such lesions.


Assuntos
Displasia Fibrosa Monostótica/diagnóstico por imagem , Doenças Mandibulares/diagnóstico por imagem , Adolescente , Adulto , Idoso , Criança , Feminino , Displasia Fibrosa Monostótica/patologia , Humanos , Índia , Masculino , Doenças Mandibulares/patologia , Doenças Maxilares/diagnóstico por imagem , Doenças Maxilares/patologia , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Adulto Jovem
16.
Nature ; 429(6992): 638-42, 2004 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-15190311

RESUMO

The standard model of particle physics contains parameters--such as particle masses--whose origins are still unknown and which cannot be predicted, but whose values are constrained through their interactions. In particular, the masses of the top quark (M(t)) and W boson (M(W)) constrain the mass of the long-hypothesized, but thus far not observed, Higgs boson. A precise measurement of M(t) can therefore indicate where to look for the Higgs, and indeed whether the hypothesis of a standard model Higgs is consistent with experimental data. As top quarks are produced in pairs and decay in only about 10(-24) s into various final states, reconstructing their masses from their decay products is very challenging. Here we report a technique that extracts more information from each top-quark event and yields a greatly improved precision (of +/- 5.3 GeV/c2) when compared to previous measurements. When our new result is combined with our published measurement in a complementary decay mode and with the only other measurements available, the new world average for M(t) becomes 178.0 +/- 4.3 GeV/c2. As a result, the most likely Higgs mass increases from the experimentally excluded value of 96 to 117 GeV/c2, which is beyond current experimental sensitivity. The upper limit on the Higgs mass at the 95% confidence level is raised from 219 to 251 GeV/c2.

17.
Phys Rev Lett ; 89(26): 261801, 2002 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-12484810

RESUMO

We report the first search for supersymmetric particles via s-channel production and decay of smuons or muon sneutrinos at hadronic colliders. The data for the two-muon and two-jets final states were collected by the D0 experiment and correspond to an integrated luminosity of 94+/-5 pb(-1). Assuming that R parity is violated via the single coupling lambda'211, the number of candidate events is in agreement with expectation from the standard model. Exclusion contours are given in the (m(0),m(1/2)) and (m(x),m(v)) planes for lambda(')(211)=0.09, 0.08, and 0.07.

18.
Phys Rev E Stat Nonlin Soft Matter Phys ; 63(5 Pt 1): 051702, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11414916

RESUMO

The static and dynamic aspects of (4-n-heptyl-4'-cyanobiphenyl) (7CB) perturbed by the dispersion of 70-A-diameter hydrophilic silica aerosil spheres have been investigated using dielectric spectroscopy. Results on five mixtures of 7CB plus silica aerosil are presented in order to probe systematically the disorder introduced by the silica aerosil network on the 7CB molecules. Measurements on homeotropically aligned samples have been made from 75 kHz to 30 MHz in the temperature range 30-60 degrees C. It was found for the mixtures that the nematic-isotropic transition temperature is lower than that of the bulk 7CB. Bulklike relaxation processes due to the rotation of the molecules around the short axis have been analyzed, and were found to follow Arrhenius-type behavior in the nematic phase except in the vicinity of the nematic-isotropic transition temperature. These processes are slightly faster in the mixture than in the free phase. A dielectric process in the low frequency range, absent in the bulk, has been observed in samples with higher silica concentration. All the observed relaxation processes in the mixtures are of non-Debye type.

19.
Ultrasonics ; 39(3): 203-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11350001

RESUMO

The use of the signal processing techniques based on the principle of quasi-frequency diversity can be a suitable solution for the ultrasonic inspection of liquid hydrogen tanks manufactured out of composite materials. Nevertheless, the algorithms developed up to now suffer from limitations that restrict their large-scale use. The split-spectrum processing requires preliminary adjustments that are not always accessible to the user, while the cut-spectrum processing is not sensitive enough to eliminate the noise. We have thus developed an interesting alternative to these two filters. Based on the use of progressive low-pass filters, this algorithm, called low-spectrum processing, takes into account the physical characteristics of the ultrasonic wave propagation in a composite material. Its use in the inspection of tanks made in composites showed better performances.

20.
J Indian Med Assoc ; 98(6): 318-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11002641

RESUMO

Usual torture victims examined by doctors do not have any physical evidence but careful history concerning the method of torture and their effect may provide important evidence. Psychological assessment is very important and will invariably reveal torture. The injury if present to be evaluated against the history and documented as common clinical documentation. Proper documentation is the best campaign of a doctor against torture.


Assuntos
Jurisprudência , Tortura/legislação & jurisprudência , Ferimentos e Lesões/classificação , Documentação , Feminino , Humanos , Índia , Escala de Gravidade do Ferimento , Masculino , Anamnese , Tortura/psicologia
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