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1.
J Chem Phys ; 160(20)2024 May 28.
Article in English | MEDLINE | ID: mdl-38785285

ABSTRACT

Small anionic nickel clusters with ethanol are investigated with a combination of mass-selective infrared photodissociation spectroscopy in a molecular beam and density functional theory simulations at the BLYP/6-311g(d,p) and TPSSh/def2-TZVPP level. In this context, the O-H stretching vibration of the ethanol is analyzed to obtain information about the structural motif, the geometry of the metal core, and the spin state of the clusters. For the [Ni2(EtOH)]- and [Ni3(EtOH)]- clusters, we assign quartet states of motifs with a hydrogen bond from the ethanol to the linear nickel core. The aggregation of a further ethanol molecule, yielding the [Ni3(EtOH)2]- cluster, results in the formation of a cooperative hydrogen bond network between the nickel core and the two ethanol molecules.

2.
Environ Sci Technol ; 58(5): 2271-2281, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38270974

ABSTRACT

To mitigate methane emission from urban natural gas distribution systems, it is crucial to understand local leak rates and occurrence rates. To explore urban methane emissions in cities outside the U.S., where significant emissions were found previously, mobile measurements were performed in 12 cities across eight countries. The surveyed cities range from medium size, like Groningen, NL, to large size, like Toronto, CA, and London, UK. Furthermore, this survey spanned across European regions from Barcelona, ES, to Bucharest, RO. The joint analysis of all data allows us to focus on general emission behavior for cities with different infrastructure and environmental conditions. We find that all cities have a spectrum of small, medium, and large methane sources in their domain. The emission rates found follow a heavy-tailed distribution, and the top 10% of emitters account for 60-80% of total emissions, which implies that strategic repair planning could help reduce emissions quickly. Furthermore, we compare our findings with inventory estimates for urban natural gas-related methane emissions from this sector in Europe. While cities with larger reported emissions were found to generally also have larger observed emissions, we find clear discrepancies between observation-based and inventory-based emission estimates for our 12 cities.


Subject(s)
Air Pollutants , Natural Gas , Cities , Natural Gas/analysis , Methane/analysis , Air Pollutants/analysis , London
4.
Phys Chem Chem Phys ; 19(43): 29438-29448, 2017 Nov 08.
Article in English | MEDLINE | ID: mdl-29077123

ABSTRACT

Understanding subtle aspects of photophysical behavior is the key to design and synthesize new and improved luminescent materials. We contribute to this with an in-depth photophysical characterization of the binuclear copper complex Cu(i)-NHetPHOS-tris-m-tolylphosphine (1), a member of a recently established emitter class for ultra-efficient, printed organic light-emitting diodes (OLEDs). To this end we studied 1 in solution and in solid form, i.e. neat film and KBr-pellet, by means of femtosecond time-resolved transient absorption/reflectivity, time-correlated single photon counting (TCSPC), and nanosecond time-resolved step-scan FTIR spectroscopy. Using these methods, we explore the photoinduced dynamics from ultrafast Franck-Condon state deactivation until the decay of the luminescent states. Upon photoexcitation, we observed multiexponential dynamics in both solution (e.g. acetonitrile 0.8 ps, 59 ps, 3 ns, 11-13 ns) and in solid state (e.g. neat film 0.3 ps, 35 ps, 670 ps, 0.5-1 µs, 3.5-4.5 µs) with four to five time-constants that significantly depend on the type of sample. Quantum chemical calculations at the DFT level in combination with step-scan vibrational spectroscopy provided structural information about the electronic ground state S0 and the lowest lying excited state T1, and show that the latter is populated within 1 µs after photoexcitation. We found thermally activated delayed fluorescence (TADF) for this complex, which has been suggested to be the cause for its high efficiency in printed OLED devices. The results suggest that non-radiative processes, lowering the luminescence quantum yield in solution, are active on the ns to µs timescale.

5.
Z Orthop Unfall ; 153(1): 46-50, 2015 Feb.
Article in German | MEDLINE | ID: mdl-25723580

ABSTRACT

BACKGROUND: Currently, short cementless femoral stems are alternative implants to treat osteoarthritis in young patients with sufficient bone quality in order to get a more proximal load transfer. The purpose of the present study was to biomechanically compare joint reconstructions resulting from implantations of a short-stemmed and a conventional hip replacement. METHODS: 100 patients (50 short-stemmed and 50 conventional) were retrospectively examined. For evaluation of biomechanical parameters standardised pre- and postoperative X-rays (pelvic AP views) were used and digitally analysed. RESULTS: The horizontal femoral off-set increased within both groups (short: 2.0 mm and conventional: 3.3 mm), with a significant increase in the conventional group. The hip centre of rotation was significantly medialised after both procedures (short: 6.0 mm and conventional: 4.2 mm). Limb length was shorter preoperatively at the arthroplasty side, but increased thereafter (short: 2.1 mm and conventional: 2.6 mm). Compared to the native contralateral side the limb length was almost equal after THA (short: 0.7 mm and conventional: 0.8 mm). CONCLUSIONS: Our study shows that an almost anatomic reconstruction of hip joint biomechanics is possible with a short-stemmed prosthesis compared to a conventional stem, regarding limb length, centre of rotation and offset.


Subject(s)
Arthroplasty, Replacement, Hip/instrumentation , Hip Joint/diagnostic imaging , Hip Joint/physiopathology , Hip Prosthesis , Osteoarthritis, Hip/physiopathology , Osteoarthritis, Hip/surgery , Arthroplasty, Replacement, Hip/methods , Equipment Failure Analysis , Female , Hip Joint/surgery , Humans , Male , Middle Aged , Osteoarthritis, Hip/diagnosis , Prosthesis Design , Radiography , Range of Motion, Articular , Treatment Outcome
6.
Z Orthop Unfall ; 151(5): 497-502, 2013 Oct.
Article in German | MEDLINE | ID: mdl-24129720

ABSTRACT

BACKGROUND: The design and the surgical technique of the Silent Micro Hip™ are different compared to other hip stems due to a conical shape for fixation within the metaphyseal femur. The purpose of the present study was to evaluate hip joint biomechanics of the Silent Micro Hip™ in comparison to other implants. Implant-specific differences are highlighted. MATERIAL AND METHOD: 150 consecutive patients (each group 50 Silent Micro Hip™, Nanos™ and SL-Plus™ MIA) were analysed retrospectively. For evaluation of biomechanical parameters pre- and postoperative X-rays (pelvic AP views) were used. RESULTS: The horizontal femoral offset and the limb length showed no significant difference between the Silent Micro Hip™ and the Nanos™ or SL-Plus™ MIA stem at the reconstructed hip. An almost anatomic reconstruction of hip joint biomechanics was reached with all three types of implants. CONCLUSIONS: The Silent Micro Hip™ allows for almost anatomic reconstruction of hip joint biomechanics. Short-term results support the bone-preserving reconstruction with a proximal femoral load transfer. Further studies on the mid- and long-term outcomes are ongoing.


Subject(s)
Hip Joint/physiopathology , Hip Joint/surgery , Hip Prosthesis , Organ Sparing Treatments/methods , Osteoarthritis, Hip/physiopathology , Osteoarthritis, Hip/surgery , Range of Motion, Articular , Arthroplasty, Replacement, Hip/instrumentation , Arthroplasty, Replacement, Hip/methods , Equipment Failure Analysis , Female , Humans , Male , Middle Aged , Miniaturization , Organ Sparing Treatments/instrumentation , Osteoarthritis, Hip/pathology , Prosthesis Design , Treatment Outcome
7.
Article in English | MEDLINE | ID: mdl-23719696

ABSTRACT

Invarioms are aspherical atomic scattering factors that enable structure refinement of more accurate and more precise geometries than refinements with the conventional independent atom model (IAM). The use of single-crystal X-ray diffraction data of a resolution better than sin θ/λ = 0.6 Å(-1) (or d = 0.83 Å) is recommended. The invariom scattering-factor database contains transferable pseudoatom parameters of the Hansen-Coppens multipole model and associated local atomic coordinate systems. Parameters were derived from geometry optimizations of suitable model compounds, whose IUPAC names are also contained in the database. Correct scattering-factor assignment and orientation reproduces molecular electron density to a good approximation. Molecular properties can hence be derived directly from the electron-density model. Coverage of chemical environments in the invariom database has been extended from the original amino acids, proteins and nucleic acid structures to many other environments encountered in organic chemistry. With over 2750 entries it now covers a wide sample of general organic chemistry involving the elements H, C, N and O, and to a lesser extent F, Si, S, P and Cl. With respect to the earlier version of the database, the main modification concerns scattering-factor notation. Modifications improve ease of use and success rates of automatic geometry-based scattering-factor assignment, especially in condensed hetero-aromatic ring systems, making the approach well suited to replace the IAM for structures of organic molecules.

8.
Z Orthop Unfall ; 151(3): 296-301, 2013 Jun.
Article in German | MEDLINE | ID: mdl-23696161

ABSTRACT

INTRODUCTION: The chronic lateral epicondylitis (EHR) as a common pathology of the elbow is often associated with posterolateral rotatory instability of the elbow (PLRI). After evaluation of intra-articular pathology by prior diagnostic arthroscopy, we aimed to build patient groups regarding the stability of the elbow joint. In patients with a stable elbow joint, open surgery with a debridement to the origin of the common extensor tendon and transosseous refixation was performed. Patients with relevant posterolateral rotatory instability, however, underwent an additional LUCL complex stabilisation using triceps tendon graft besides debridement as mentioned above. The purpose of this study was to evaluate and compare the clinical functional outcome between these groups. MATERIAL AND METHODS: 101 patients were included in our study. Arthroscopies were first performed on all patients to identify intra-articular pathological changes. In 26 patients with stable elbows, open surgery with debridement to the origin of the common extensor tendon and transosseous refixation was performed. For the other 75 patients who were found presenting a relevant posterolateral rotatory instability, a stabilisation of the LUCL in addition to the open procedure mentioned above was performed. Examinations and questionnaires were used for retrospective evaluation at follow-up. RESULTS: Both groups of patients revealed significant improvement in pain relief and elbow function. We observed no significant difference between the two methods concerning clinical and functional outcome. CONCLUSION: We recommend diagnostic arthroscopy with assessment of stability prior to the open performance to offer a more reliable evidence for surgical technique selection and therefore to achieve a better clinical outcome.


Subject(s)
Arthroscopy/statistics & numerical data , Debridement/statistics & numerical data , Patient Satisfaction/statistics & numerical data , Plastic Surgery Procedures/statistics & numerical data , Tendon Transfer/statistics & numerical data , Tennis Elbow/epidemiology , Tennis Elbow/surgery , Adult , Aged , Combined Modality Therapy/statistics & numerical data , Female , Germany/epidemiology , Humans , Male , Middle Aged , Prevalence , Recovery of Function , Retrospective Studies , Risk Factors , Tennis Elbow/diagnosis , Treatment Outcome , Young Adult
9.
J Ultrason ; 13(52): 73-81, 2013 Mar.
Article in English | MEDLINE | ID: mdl-26675994

ABSTRACT

Sentinel lymph nodes are the first lymph nodes in the region that receive lymphatic drainage from a primary tumor. The detection or exclusion of sentinel lymph node micrometastases is critical in the staging of cancer, especially breast cancer and melanoma because it directly affects patient's prognosis and surgical management. Currently, intraoperative sentinel lymph node biopsies using blue dye and radioisotopes are the method of choice for the detection of sentinel lymph node with high identification rate. In contrast, conventional ultrasound is not capable of detecting sentinel lymph nodes in most cases. Contrast enhanced ultrasound with contrast specific imaging modes has been used for the evaluation and diagnostic work-up of peripherally located suspected lymphadenopathy. The method allows for real-time analysis of all vascular phases and the visualization of intranodal focal "avascular" areas that represent necrosis or deposits of neoplastic cells. In recent years, a number of animal and human studies showed that contrast enhanced ultrasound can be also used for the detection of sentinel lymph node, and may become a potential application in clinical routine. Several contrast agents have been used in those studies, including albumin solution, hydroxyethylated starch, SonoVue(®), Sonazoid(®) and Definity(®). This review summarizes the current knowledge about the use of ultrasound techniques in detection and evaluation of sentinel lymph node.

10.
Phys Rev Lett ; 105(20): 202502, 2010 Nov 12.
Article in English | MEDLINE | ID: mdl-21231224

ABSTRACT

A microscopic calculation of reaction cross sections for nucleon-nucleus scattering was performed by coupling the elastic channel to all particle-hole excitations in the target and one-nucleon pickup channels. The particle-hole states may be regarded as doorway states through which the flux flows to more complicated configurations, and subsequently to long-lived compound nucleus resonances. Target excitations for (40,48)Ca, 58Ni, 90Zr, and 144Sm were described in a random-phase framework using a Skyrme functional. Reaction cross sections obtained agreed very well with experimental data and predictions of a fitted optical potential. Couplings between inelastic states were found to be negligible, while the pickup channels contribute significantly. For the first time observed absorptions are completely accounted for by explicit channel coupling, for incident energies between 10 and 40 MeV.


Subject(s)
Models, Molecular , Quantum Theory , Elasticity , Thermodynamics
11.
J Invest Dermatol ; 129(4): 899-907, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18830270

ABSTRACT

Due to the steadily increasing incidence of atopic dermatitis (AD), especially in children, there is a high medical need for new therapies and improved animal models. In mice, trimellitic anhydride (TMA) is routinely used to trigger T-cell-dependent contact hypersensitivity (CHS) reactions. In this study, we compared the standard acute TMA-induced CHS in Balb/c mice with subacute and chronic models of TMA-induced ear inflammation. Compared to the acute model, the chronic CHS model more closely reflects characteristics of AD, such as typical morphological changes of the inflamed skin, strong infiltration with T cells, major histocompatibility complex II-positive cells, eosinophils, and mast cells, a T-helper cell-type (Th) 2 cytokine profile and a strong increase of serum IgE levels. Moreover, a strong lymph node involvement with T-helper cell dominance and a mixed Th1/Th2 T-cell differentiation and activation pattern was demonstrated. Importantly, as demonstrated by successful therapy with prednisolone, the chronic TMA-induced CHS model, in contrast to acute and subacute models, made prolonged therapeutic treatment of a pre-established skin inflammation possible. Altogether, we present an improved model of mouse T-cell-dependent skin inflammation for AD. We hope this model will enhance the predictive value of animal models for therapeutic treatment of atopic eczema.


Subject(s)
Dermatitis, Contact/etiology , Disease Models, Animal , Phthalic Anhydrides/toxicity , Animals , Chronic Disease , Cytokines/biosynthesis , Dermatitis, Contact/drug therapy , Dermatitis, Contact/immunology , Dermatitis, Contact/pathology , Female , Immunoglobulin E/blood , Lymph Nodes/immunology , Mice , Mice, Inbred BALB C , Prednisolone/therapeutic use , Skin/immunology , Skin/pathology , T-Lymphocytes/immunology
12.
J Invest Dermatol ; 127(4): 835-45, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17235328

ABSTRACT

A mixture of different fumaric acid esters (FAE) is established for systemic therapy of psoriasis, a frequent inflammatory skin disease. The main active compound of FAE, however, has not been identified so far, and the mechanisms of activity are only partially understood. We analyzed the impact of FAE on in vitro immune function and aimed to gain knowledge about the mode of action. Dimethylfumarate (DMF) and diethylfumarate (DEF), but not fumaric acid, methylhydrogenfumarate and ethylhydrogenfumarate, exhibited potent depression of inflammatory cytokine secretion (e.g., tumor necrosis factoralpha, IL-12, and IFNgamma) in activated human peripheral blood mononuclear cells. Moreover, solely DMF and DEF inhibited alloreactive T-cell proliferation in mixed leukocyte reaction. Interestingly, these immunosuppressive effects were accompanied by the strong induction of the anti-inflammatory stress protein heme oxygenase 1 (HO-1). Supplementation with exogenous glutathione (GSH), which is known to bind DMF, prevented both HO-1 induction as well as the anti-inflammatory effects of DMF. Moreover, inhibition of HO-1 activity restored the diminished IL-12 and IFNgamma production after FAE treatment. These results suggest that DMF acts as active compound within the FAE mixture and at least partially mediates its immunomodulatory activity by the induction of the anti-inflammatory stress protein HO-1 ascribed to the functional depletion of reduced GSH.


Subject(s)
Fumarates/pharmacology , Glutathione/antagonists & inhibitors , Heme Oxygenase-1/biosynthesis , Immunosuppressive Agents/pharmacology , Cell Proliferation/drug effects , Cells, Cultured , Cytokines/antagonists & inhibitors , Dimethyl Fumarate , Dose-Response Relationship, Drug , Enzyme Induction/drug effects , Fumarates/administration & dosage , Glutathione/analogs & derivatives , Glutathione/pharmacology , Heme Oxygenase-1/antagonists & inhibitors , Heme Oxygenase-1/genetics , Humans , Immunosuppressive Agents/administration & dosage , Inflammation Mediators/antagonists & inhibitors , Interferon-gamma/antagonists & inhibitors , Interferon-gamma/metabolism , Interleukin-12/antagonists & inhibitors , Interleukin-12/metabolism , Lymphocytes/cytology , RNA, Small Interfering/pharmacology , Tumor Necrosis Factor-alpha/metabolism
13.
Neuropediatrics ; 34(6): 293-300, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14681754

ABSTRACT

30 patients (23 m/7 f) with untreated, isolated sagittal craniosynostosis (ISC) were re-evaluated at an average age of 9.25 years (2.5 - 25.5). Assessed were neurological status, head shape, school performance, behaviour (with Child Behavior Checklist CBCL), quality of life (TACQOL questionnaire), and a detailed neuropsychological testing (30 patients, 17 siblings as controls). Almost all patients/parents were pleased with the current situation. The aesthetic appearance seemed less obvious compared to photos in infancy. Psychological adjustment as measured by the CBCL was well within normal range. There was a slight tendency for increased internalizing symptoms. TACQOL revealed a lower score for positive emotions. Total score and subscores of test batteries assessing general intellectual performance were in the average range. 6 patients had below average scores in subtests for learning and memory. 12 children had below average scores in one or more subtests for attention. These "deficits" were obviously not of functional importance as all children attended regular school classes (1 exception, an immigrant child of low socio-economic status). These reassuring results regarding school performances, behaviour, and quality of life as well as aesthetic outcome may be helpful when discussing the indication for surgical correction of ISC.


Subject(s)
Cognition/physiology , Cranial Sutures/abnormalities , Craniosynostoses/psychology , Intelligence , Mental Disorders/etiology , Quality of Life/psychology , Adolescent , Adult , Child , Child, Preschool , Educational Measurement , Female , Humans , Male , Neuropsychological Tests
14.
Article in English | MEDLINE | ID: mdl-12471494

ABSTRACT

Biological systems by default involve complex components with complex relationships. To decipher how biological systems work, we assume that one needs to integrate information over multiple levels of complexity. The songbird vocal communication system is ideal for such integration due to many years of ethological investigation and a discreet dedicated brain network. Here we announce the beginnings of a songbird brain integrative project that involves high-throughput, molecular, anatomical, electrophysiological and behavioral levels of analysis. We first formed a rationale for inclusion of specific biological levels of analysis, then developed high-throughput molecular technologies on songbird brains, developed technologies for combined analysis of electrophysiological activity and gene regulation in awake behaving animals, and developed bioinformatic tools that predict causal interactions within and between biological levels of organization. This integrative brain project is fitting for the interdisciplinary approaches taken in the current songbird issue of the Journal of Comparative Physiology A and is expected to be conducive to deciphering how brains generate and perceive complex behaviors.


Subject(s)
Brain/physiology , Songbirds/physiology , Animals , Auditory Pathways , Bayes Theorem , Brain/anatomy & histology , Brain Mapping , Computational Biology , Computer Simulation , DNA-Binding Proteins/metabolism , Electrophysiology , Gene Expression Profiling , Gene Expression Regulation, Developmental , Gene Library , Learning , Models, Neurological , Motor Activity/physiology , Nerve Net , Neural Networks, Computer , Transcription Factors/metabolism , Vocalization, Animal/physiology
15.
Zentralbl Chir ; 126(5): 391-5, 2001 May.
Article in German | MEDLINE | ID: mdl-11396249

ABSTRACT

We present the rare case of a solitary pancreatic metastasis of renal cell cancer being the only manifestation of tumordissemination. In 1993 the patient underwent a transperitoneal nephrectomy for removal of a clear cell renal cancer. In 1998 during follow up we detected a pancreatic tumor which was treated by pancreas resection, splenectomy and resection of the colon transversum. The histology revealed a metastasis of the previously resected renal cancer. The postoperative recovery was impaired by the development of an abcess in the former pancreatic region. During the first year of follow up we did not find any signs for local or distant tumor recurrence. Pancreas resection adapted to the location of the tumor is the treatment of choice for isolated solitary late metastases of renal cell cancer.


Subject(s)
Carcinoma, Renal Cell/secondary , Kidney Neoplasms/surgery , Pancreatic Neoplasms/secondary , Carcinoma, Renal Cell/pathology , Carcinoma, Renal Cell/surgery , Colectomy , Humans , Kidney/pathology , Kidney Neoplasms/pathology , Male , Middle Aged , Nephrectomy , Pancreas/pathology , Pancreatectomy , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/surgery , Splenectomy
16.
J Cell Sci ; 114(Pt 5): 975-86, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11181180

ABSTRACT

We have followed the migration of GFP-labelled nuclei in multinucleate hyphae of Ashbya gossypii. For the first time we could demonstrate that the mode of long range nuclear migration consists of oscillatory movements of nuclei with, on average, higher amplitudes in the direction of the growing tip. We could also show that mitotic division proceeds at a constant rate of 0. 64 microm/minute which differs from the biphasic kinetics described for the yeast Saccharomyces cerevisiae. Furthermore we were able to identify the microtubule-based motor dynein as a key element in the control of long range nuclear migration. For other filamentous fungi it had already been demonstrated that inactivating mutations in dynein led to severe problems in nuclear migration, i.e. generation of long nuclei-free hyphal tips and clusters of nuclei throughout the hyphae. This phenotype supported the view that dynein is important for the movement of nuclei towards the tip. In A. gossypii the opposite seems to be the case. A complete deletion of the dynein heavy chain gene leads to nuclear clusters exclusively at the hyphal tips and to an essentially nucleus-free network of hyphal tubes and branches. Anucleate hyphae and branches in the vicinity of nuclear clusters show actin cables and polarized actin patches, as well as microtubules. The slow growth of this dynein null mutant could be completely reverted to wild-type-like growth in the presence of benomyl, which can be explained by the observed redistribution of nuclei in the hyphal network.


Subject(s)
Ascomycota/metabolism , Cell Nucleus/metabolism , Cytoplasm/metabolism , Dyneins/metabolism , Actins/ultrastructure , Ascomycota/cytology , Ascomycota/ultrastructure , Base Sequence , Benomyl/pharmacology , DNA Primers , Dyneins/genetics , Microscopy, Electron , Microtubules/drug effects , Microtubules/ultrastructure , Mitosis , Mutagenesis
17.
J Cell Sci ; 113 Pt 24: 4563-75, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11082049

ABSTRACT

Filamentous fungi grow by hyphal extension, which is an extreme example of polarized growth. In contrast to yeast species, where polarized growth of the tip of an emerging bud is temporally limited, filamentous fungi exhibit constitutive polarized growth of the hyphal tip. In many fungi, including Ashbya gossypii, polarized growth is reinforced by a process called hyphal maturation. Hyphal maturation refers to the developmental switch from slow-growing hyphae of young mycelium to fast-growing hyphae of mature mycelium. This process is essential for efficient expansion of mycelium. We report for the first time on the identification and characterization of a fungal gene important for hyphal maturation. This novel A. gossypii gene encodes a presumptive PAK (p21-activated kinase)-like kinase. Its closest homolog is the S. cerevisiae Cla4 protein kinase; the A. gossypii protein is therefore called AgCla4p. Agcla4 deletion strains are no longer able to perform the developmental switch from young to mature hyphae, and GFP (green fluorescent protein)-tagged AgCla4p localizes with much higher frequency in mature hyphal tips than in young hyphal tips. Both results support the importance of AgCla4p in hyphal maturation. AgCla4p is also required for septation, indicated by the inability of Agcla4 deletion strains to properly form actin rings and chitin rings. Despite the requirement of AgCla4p for the development of fast-growing hyphae, AgCla4p is not necessary for actin polarization per se, because tips enriched in cortical patches and hyphae with a fully developed network of actin cables can be seen in Agcla4 deletion strains. The possibility that AgCla4p may be involved in regulatory mechanisms that control the dynamics of the actin patches and/or actin cables is discussed.


Subject(s)
Fungal Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Saccharomycetales/enzymology , Saccharomycetales/growth & development , Actins/metabolism , Base Sequence , DNA, Fungal , Fungal Proteins/genetics , Fungal Proteins/physiology , Genes, Fungal , Molecular Sequence Data , Phenotype , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/physiology , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Recombinant Fusion Proteins/physiology , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae Proteins , Subcellular Fractions , p21-Activated Kinases
18.
Curr Genet ; 35(6): 618-25, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10467006

ABSTRACT

The rDNA cluster in the phytopathogenic fungus Ashbya gossypii consists of approximately 50 tandem repeat units of 8197 bp. Each unit carries a gene for the 35S pre-rRNA, processed into 18S, 5.8S and 25S rRNA, and a divergently transcribed gene for 5S rRNA. The well-characterized rDNA of the yeast Saccharomyces cerevisiae is the only other example of a completely sequenced rDNA unit (9137 bp) carrying both a 35S pre-rRNA and a 5S rRNA gene. The coding regions for the 5S, 5.8S, 18S and 25S rRNAs are 95-100% identical whereas transcribed and non-transcribed spacers show 43-66% sequence identity. Functionally characterized rDNA and rRNA elements of S. cerevisiae can be unambiguously recognized in the A. gossypii sequence, including the RNA polymerase-I transcription start site, two Reb1p enhancer binding sites and numerous recognition sequences for rRNA modification and processing. In addition to these functionally characterized sequences eight highly conserved elements from 10 to 71 bp were detected in the over 600-bp transcribed region upstream of the 18S rRNA gene which most likely play as yet uncharacterized functions at the DNA or RNA level. In addition to this work we started to identify A. gossypii homologs of S. cerevisiae nucleolar proteins involved in rDNA maturation.


Subject(s)
Ascomycota/genetics , Genes, rRNA/genetics , Amino Acid Sequence , Ascomycota/chemistry , Base Sequence , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/genetics , Genes, Fungal/genetics , Molecular Sequence Data , Phylogeny , RNA, Ribosomal, 18S/genetics , Repetitive Sequences, Nucleic Acid , Saccharomyces cerevisiae/genetics , Sequence Alignment , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid
19.
Science ; 285(5429): 901-6, 1999 Aug 06.
Article in English | MEDLINE | ID: mdl-10436161

ABSTRACT

The functions of many open reading frames (ORFs) identified in genome-sequencing projects are unknown. New, whole-genome approaches are required to systematically determine their function. A total of 6925 Saccharomyces cerevisiae strains were constructed, by a high-throughput strategy, each with a precise deletion of one of 2026 ORFs (more than one-third of the ORFs in the genome). Of the deleted ORFs, 17 percent were essential for viability in rich medium. The phenotypes of more than 500 deletion strains were assayed in parallel. Of the deletion strains, 40 percent showed quantitative growth defects in either rich or minimal medium.


Subject(s)
Gene Deletion , Genes, Essential , Genome, Fungal , Open Reading Frames , Saccharomyces cerevisiae/genetics , Culture Media , Gene Expression Regulation, Fungal , Gene Targeting , Genes, Fungal , Phenotype , Polymerase Chain Reaction , Recombination, Genetic , Saccharomyces cerevisiae/growth & development
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