650 research outputs found
Courtship Ritual of Male and Female Nuclei during Fertilization in Neurospora crassa
This is the final version. Available on open access from the American Society for Microbiology via the DOI in this recordSexual reproduction is a key process influencing the evolution and adaptation of animals, plants, and many eukaryotic microorganisms, such as fungi. However, the sequential cell biology of fertilization and the associated nuclear dynamics after plasmogamy are poorly understood in filamentous fungi. Using histone-fluorescent parental isolates, we tracked male and female nuclei during fertilization in the model ascomycete Neurospora crassa using live-cell imaging. This study unravels the behavior of trichogyne resident female nuclei and the extraordinary manner in which male nuclei migrate up the trichogyne to the protoperithecium. Our observations raise new fundamental questions about the modus operandi of nucleus movements during sexual reproduction, male and female nuclear identity, guidance of nuclei within the trichogyne and, unexpectedly, the avoidance of "polyspermy" in fungi. The spatiotemporal dynamics of male nuclei within the trichogyne following plasmogamy are also described, where the speed and the deformation of male nuclei are of the most dramatic observed to date in a living organism. IMPORTANCE Using live-cell fluorescence imaging, for the first time we have observed live male and female nuclei during sexual reproduction in the model fungus Neurospora crassa. This study reveals the specific behavior of resident female nuclei within the trichogyne (the female organ) after fertilization and the extraordinary manner in which male nuclei migrate across the trichogyne toward their final destination, the protoperithecium, where karyogamy takes place. Importantly, the speed and deformation of male nuclei were found to be among the most dramatic ever observed in a living organism. Furthermore, we observed that entry of male nuclei into protoperithecia may block the entry of other male nuclei, suggesting that a process analogous to polyspermy avoidance could exist in fungi. Our live-cell imaging approach opens new opportunities for novel research on cell-signaling during sexual reproduction in fungi and, on a broader scale, nuclear dynamics in eukaryotes
LMDA Review, volume 11, issue 1
Contents include: Advocacy Guidelines,LMDA Members Meet with the NEA, Update The Elliot Hayes Award,Update Script Exchange, Presentation Of Elliott Hayes Award to Rebecca Rugg, To Lynn Thomson, Conference Panels and Sessions, Conversations About Digital Dramaturgy, Key Note, Dramaturg As Generator, Multi-Authorship: Too Many Cooks?, Desperately Seeking Research, On Copyright, The Dramaturg As Advocate For The Arts On City, State/Provincial, And National Levels, Entrances And Exits, The (New Play) Workshop\u27s The Thing, Anne Cattaneo On Commissioning New Work, LMDA Regions And VPs, News From Canada, News from Baltimore, News from Chicago, The Past Two Years, and On, Notes to Fellow LMDA Members, Spotlight on Early Career Dramturgs, Dramaturgy Opening Arena Stage, Internship at the Women\u27s Project, Literary Residency in New York, Dramaturgy/Literary Management Internship at Arena Stage, Job Opening at UCSD, A Note to LMDA Members, Unity Fest 2001 Call for Scripts, Call for Directors, Actors, Dramaturgs, and Call for Updates to the LMDA Guide to Programs in Dramaturgy.https://soundideas.pugetsound.edu/lmdareview/1022/thumbnail.jp
Heightened Efficacy of Anidulafungin When Used in Combination with Manogepix or 5-Flucytosine against Candida auris In Vitro.
Candida auris is an emerging, multidrug-resistant fungal pathogen that causes refractory colonization and life-threatening, invasive nosocomial infections. The high proportion of C. auris isolates that display antifungal resistance severely limits treatment options. Combination therapies provide a possible strategy by which to enhance antifungal efficacy and prevent the emergence of further resistance. Therefore, we examined drug combinations using antifungals that are already in clinical use or are undergoing clinical trials. Using checkerboard assays, we screened combinations of 5-flucytosine and manogepix (the active form of the novel antifungal drug fosmanogepix) with anidulafungin, amphotericin B, or voriconazole against drug resistant and susceptible C. auris isolates from clades I and III. Fractional inhibitory concentration indices (FICI values) of 0.28 to 0.75 and 0.36 to 1.02 were observed for combinations of anidulafungin with manogepix or 5-flucytosine, respectively, indicating synergistic activity. The high potency of these anidulafungin combinations was confirmed using live-cell microfluidics-assisted imaging of the fungal growth. In summary, combinations of anidulafungin with manogepix or 5-flucytosine show great potential against both resistant and susceptible C. auris isolates
LMDA Review, volume 10, issue 1
Contents include: Photo of Conference Participants Annual Conference 1999, Send in your Ballot, A Note to Ourselves, Increase in Dues and New Annual Membership Expiration Date, LMDA Archive, LMDA Administrator; LMDA Interns, Mid-Year Meeting, Early Career Dramaturg Program, Elliot Hayes Award 2000, Report on Canadian Caucus, Script Exchange, Report on the Dramaturgy Focus Group ATHE 1999, Elliot Hayes Award Winners Lue Douthit and Michel Volansky, Acceptance Speech Lue Morgan Douthit, Elliot Hayes Award Presentation to Michele Volansky for Space, On the Elliot Hayes Award Michele Volansky, Day One of the Conference, Day Two of the Conference, Day Three of the Conference, Day Four of the Conference, The Advocacy Caucus Presentation at the Conference, Final Thoughts, Conference 1999 Many Thanks, Arthur Ballet and the Office for Advanced Drama Research, Spotlight on Early Career Dramaturg Vanessa Porteous, A Working History of LMDA The Early Years, From Academia to Arena A Dramaturg\u27s Education in the Real World, Tony Creamer and Death of a Salesman, Two Moments, Jobs and Projects, Scriptseeker.com, LMDA Online Listserv Instructions, Note from James Magruder, Literary Managers and Dramaturgs of the Americas Bibliography 1999, Noted with Pleasure, and Internship Questionnaire.https://soundideas.pugetsound.edu/lmdareview/1020/thumbnail.jp
Fungal iron availability during deep seated candidiasis is defined by a complex interplay involving systemic and local events
Peer reviewedPublisher PD
Prevalence of Disorders Recorded in Dogs Attending Primary-Care Veterinary Practices in England
Purebred dog health is thought to be compromised by an increasing occurence of inherited diseases but inadequate prevalence data on common disorders have hampered efforts to prioritise health reforms. Analysis of primary veterinary practice clinical data has been proposed for reliable estimation of disorder prevalence in dogs. Electronic patient record (EPR) data were collected on 148,741 dogs attending 93 clinics across central and south-eastern England. Analysis in detail of a random sample of EPRs relating to 3,884 dogs from 89 clinics identified the most frequently recorded disorders as otitis externa (prevalence 10.2%, 95% CI: 9.1-11.3), periodontal disease (9.3%, 95% CI: 8.3-10.3) and anal sac impaction (7.1%, 95% CI: 6.1-8.1). Using syndromic classification, the most prevalent body location affected was the head-and-neck (32.8%, 95% CI: 30.7-34.9), the most prevalent organ system affected was the integument (36.3%, 95% CI: 33.9-38.6) and the most prevalent pathophysiologic process diagnosed was inflammation (32.1%, 95% CI: 29.8-34.3). Among the twenty most-frequently recorded disorders, purebred dogs had a significantly higher prevalence compared with crossbreds for three: otitis externa (P = 0.001), obesity (P = 0.006) and skin mass lesion (P = 0.033), and popular breeds differed significantly from each other in their prevalence for five: periodontal disease (P = 0.002), overgrown nails (P = 0.004), degenerative joint disease (P = 0.005), obesity (P = 0.001) and lipoma (P = 0.003). These results fill a crucial data gap in disorder prevalence information and assist with disorder prioritisation. The results suggest that, for maximal impact, breeding reforms should target commonly-diagnosed complex disorders that are amenable to genetic improvement and should place special focus on at-risk breeds. Future studies evaluating disorder severity and duration will augment the usefulness of the disorder prevalence information reported herein
Use of placebo interventions among Swiss primary care providers
Background: Placebo interventions can have meaningful effects for patients. However, little is known about the circumstances of their use in clinical practice. We aimed to investigate to what extent and in which way Swiss primary care providers use placebo interventions. Furthermore we explored their ideas about the ethical and legal issues involved.
Methods: 599 questionnaires were sent to general practitioners (GPs) and paediatricians in private practice in the Canton of Zurich in Switzerland. To allow for subgroup analysis GPs in urban, suburban, and rural areas as well as paediatricians were selected in an even ratio.
Results: 233 questionnaires were completed (response rate 47%). 28% of participants reported that they never used placebo interventions. More participants used impure placebos therapeutically than pure placebos (57% versus 17%, McNemar's chi2 = 78, p<0.001). There is not one clear main reason for placebo prescription. Placebo use was communicated to patients mostly as being "a drug or a therapy" (64%). The most frequently chosen ethical premise was that they "can be used as long as the physician and the patient work together in partnership" (60% for pure and 75% for impure placebos, McNemar's chi2 = 12, p<0.001). A considerable number of participants (11-38%) were indecisive about statements regarding the ethical and legal legitimacy of using placebos.
Conclusions: The data obtained from Swiss primary care providers reflect a broad variety of views about placebo interventions as well as a widespread uncertainty regarding their legitimacy. Primary care providers seem to preferentially use impure as compared to pure placebos in their daily practice. An intense debate is required on appropriate standards regarding the clinical use of placebo interventions among medical professionals
The Chlamydia psittaci Genome: A Comparative Analysis of Intracellular Pathogens
Chlamydiaceae are a family of obligate intracellular pathogens causing a wide range of diseases in animals and humans, and facing unique evolutionary constraints not encountered by free-living prokaryotes. To investigate genomic aspects of infection, virulence and host preference we have sequenced Chlamydia psittaci, the pathogenic agent of ornithosis.A comparison of the genome of the avian Chlamydia psittaci isolate 6BC with the genomes of other chlamydial species, C. trachomatis, C. muridarum, C. pneumoniae, C. abortus, C. felis and C. caviae, revealed a high level of sequence conservation and synteny across taxa, with the major exception of the human pathogen C. trachomatis. Important differences manifest in the polymorphic membrane protein family specific for the Chlamydiae and in the highly variable chlamydial plasticity zone. We identified a number of psittaci-specific polymorphic membrane proteins of the G family that may be related to differences in host-range and/or virulence as compared to closely related Chlamydiaceae. We calculated non-synonymous to synonymous substitution rate ratios for pairs of orthologous genes to identify putative targets of adaptive evolution and predicted type III secreted effector proteins.This study is the first detailed analysis of the Chlamydia psittaci genome sequence. It provides insights in the genome architecture of C. psittaci and proposes a number of novel candidate genes mostly of yet unknown function that may be important for pathogen-host interactions
mTOR Controls Ovarian Follicle Growth by Regulating Granulosa Cell Proliferation
We have shown that inhibition of mTOR in granulosa cells and ovarian follicles results in compromised granulosa proliferation and reduced follicle growth. Further analysis here using spontaneously immortalized rat granulosa cells has revealed that mTOR pathway activity is enhanced during M-phase of the cell cycle. mTOR specific phosphorylation of p70S6 kinase and 4E-BP, and expression of Raptor are all enhanced during M-phase. The predominant effect of mTOR inhibition by the specific inhibitor Rapamycin (RAP) was a dose-responsive arrest in the G1 cell cycle stage. The fraction of granulosa cells that continued to divide in the presence of RAP exhibited a dose-dependent increase in aberrant mitotic figures known as anaphase bridges. Strikingly, estradiol consistently decreased the incidence of aberrant mitotic figures. In mice treated with RAP, the mitotic index was reduced compared to controls, and a similar increase in aberrant mitotic events was noted. RAP injected during a superovulation regime resulted in a dose-dependent reduction in the numbers of eggs ovulated. Implications for the real-time regulation of follicle growth and dominance, including the consequences of increased numbers of aneuploid granulosa cells, are discussed
Striatal Dopamine Transmission Is Subtly Modified in Human A53Tα-Synuclein Overexpressing Mice
Mutations in, or elevated dosage of, SNCA, the gene for α-synuclein (α-syn), cause familial Parkinson's disease (PD). Mouse lines overexpressing the mutant human A53Tα-syn may represent a model of early PD. They display progressive motor deficits, abnormal cellular accumulation of α-syn, and deficits in dopamine-dependent corticostriatal plasticity, which, in the absence of overt nigrostriatal degeneration, suggest there are age-related deficits in striatal dopamine (DA) signalling. In addition A53Tα-syn overexpression in cultured rodent neurons has been reported to inhibit transmitter release. Therefore here we have characterized for the first time DA release in the striatum of mice overexpressing human A53Tα-syn, and explored whether A53Tα-syn overexpression causes deficits in the release of DA. We used fast-scan cyclic voltammetry to detect DA release at carbon-fibre microelectrodes in acute striatal slices from two different lines of A53Tα-syn-overexpressing mice, at up to 24 months. In A53Tα-syn overexpressors, mean DA release evoked by a single stimulus pulse was not different from wild-types, in either dorsal striatum or nucleus accumbens. However the frequency responsiveness of DA release was slightly modified in A53Tα-syn overexpressors, and in particular showed slight deficiency when the confounding effects of striatal ACh acting at presynaptic nicotinic receptors (nAChRs) were antagonized. The re-release of DA was unmodified after single-pulse stimuli, but after prolonged stimulation trains, A53Tα-syn overexpressors showed enhanced recovery of DA release at old age, in keeping with elevated striatal DA content. In summary, A53Tα-syn overexpression in mice causes subtle changes in the regulation of DA release in the striatum. While modest, these modifications may indicate or contribute to striatal dysfunction
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