97 research outputs found

    Molecular cytogenetic mapping of Cucumis sativus and C. melo using highly repetitive DNA sequences

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    Chromosomes often serve as one of the most important molecular aspects of studying the evolution of species. Indeed, most of the crucial mutations that led to differentiation of species during the evolution have occurred at the chromosomal level. Furthermore, the analysis of pachytene chromosomes appears to be an invaluable tool for the study of evolution due to its effectiveness in chromosome identification and precise physical gene mapping. By applying fluorescence in situ hybridization of 45S rDNA and CsCent1 probes to cucumber pachytene chromosomes, here, we demonstrate that cucumber chromosomes 1 and 2 may have evolved from fusions of ancestral karyotype with chromosome number n= 12. This conclusion is further supported by the centromeric sequence similarity between cucumber and melon, which suggests that these sequences evolved from a common ancestor. It may be after or during speciation that these sequences were specifically amplified, after which they diverged and specific sequence variants were homogenized. Additionally, a structural change on the centromeric region of cucumber chromosome 4 was revealed by fiber-FISH using the mitochondrial-related repetitive sequences, BAC-E38 and CsCent1. These showed the former sequences being integrated into the latter in multiple regions. The data presented here are useful resources for comparative genomics and cytogenetics of Cucumis and, in particular, the ongoing genome sequencing project of cucumbe

    Jastrow-type calculations of one-nucleon removal reactions on open ss-dd shell nuclei

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    Single-particle overlap functions and spectroscopic factors are calculated on the basis of Jastrow-type one-body density matrices of open-shell nuclei constructed by using a factor cluster expansion. The calculations use the relationship between the overlap functions corresponding to bound states of the (A1)(A-1)-particle system and the one-body density matrix for the ground state of the AA-particle system. In this work we extend our previous analyses of reactions on closed-shell nuclei by using the resulting overlap functions for the description of the cross sections of (p,d)(p,d) reactions on the open ss-dd shell nuclei 24^{24}Mg, 28^{28}Si and 32^{32}S and of 32^{32}S(e,ep)(e,e^{\prime}p) reaction. The relative role of both shell structure and short-range correlations incorporated in the correlation approach on the spectroscopic factors and the reaction cross sections is pointed out.Comment: 11 pages, 5 figures, to be published in Phys. Rev.

    A line-of-sight electron cyclotron emission receiver for electron cyclotron resonance heating feedback control of tearing modes

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    An electron cyclotron emission (ECE) receiver inside the electron cyclotron resonance heating (ECRH) transmission line has been brought into operation. The ECE is extracted by placing a quartz plate acting as a Fabry¿Perot interferometer under an angle inside the electron cyclotron wave (ECW) beam. ECE measurements are obtained during high power ECRH operation. Thisdemonstrates the successful operation of the diagnostic and, in particular, a sufficient suppression of the gyrotron component preventing it from interfering with ECE measurements. When integratedinto a feedback system for the control of plasma instabilities this line-of-sight ECE diagnosticremoves the need to localize the instabilities in absolute coordinates

    Pseudogap formation of four-layer BaRuO3_3 and its electrodynamic response changes

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    We investiaged the optical properties of four-layer BaRuO3_{3}, which shows a fermi-liquid-like behavior at low temperature. Its optical conductivity spectra clearly displayed the formation of a pseudogap and the development of a coherent peak with decreasing temperature. Temperature-dependences of the density nn and the scattering rate 1/τ1/\tau of the coherent component were also derived. As the temperature decreases, both nn and 1/τ1/\tau decrease for four-layer BaRuO3_{3}. These electrodynamic responses were compared with those of nine-layer BaRuO3_{3}, which also shows a pseudogap formation but has an insulator-like state at low temperature. It was found that the relative rates of change of both nn and 1/τ1/\tau determine either metallic or insulator-like responses in the ruthenates. The optical properties of the four-layer ruthenate were also compared with those of other pseudogap systems, such as high TcT_{c} cuprates and heavy electron systems.Comment: 7 figures. submitted to Phys. Rev.

    Cross-reactivity of IgM anti-modified protein antibodies in rheumatoid arthritis despite limited mutational load

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    Background Anti-modified protein antibodies (AMPA) targeting citrullinated, acetylated and/or carbamylated self-antigens are hallmarks of rheumatoid arthritis (RA). Although AMPA-IgG cross-reactivity to multiple post-translational modifications (PTMs) is evident, it is unknown whether the first responding B cells, expressing IgM, display similar characteristics or if cross-reactivity is crucially dependent on somatic hypermutation (SHM). We now studied the reactivity of (germline) AMPA-IgM to further understand the breach of B cell tolerance and to identify if cross-reactivity depends on extensive SHM. Moreover, we investigated whether AMPA-IgM can efficiently recruit immune effector mechanisms. Methods Polyclonal AMPA-IgM were isolated from RA patients and assessed for cross-reactivity towards PTM antigens. AMPA-IgM B cell receptor sequences were obtained by single cell isolation using antigen-specific tetramers. Subsequently, pentameric monoclonal AMPA-IgM, their germline counterparts and monomeric IgG variants were generated. The antibodies were analysed on a panel of PTM antigens and tested for complement activation. Results Pentameric monoclonal and polyclonal AMPA-IgM displayed cross-reactivity to multiple antigens and different PTMs. PTM antigen recognition was still present, although reduced, after reverting the IgM into germline. Valency of AMPA-IgM was crucial for antigen recognition as PTM-reactivity significantly decreased when AMPA-IgM were expressed as IgG. Furthermore, AMPA-IgM was 15- to 30-fold more potent in complement-activation compared to AMPA-IgG. Conclusions We provide first evidence that AMPA-IgM are cross-reactive towards different PTMs, indicating that PTM (cross-)reactivity is not confined to IgG and does not necessarily depend on extensive somatic hypermutation. Moreover, our data indicate that a diverse set of PTM antigens could be involved in the initial tolerance breach in RA and suggest that AMPA-IgM can induce complement-activation and thereby inflammation.Pathophysiology and treatment of rheumatic disease

    Large-scale phenotyping of patients with long COVID post-hospitalization reveals mechanistic subtypes of disease

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    One in ten severe acute respiratory syndrome coronavirus 2 infections result in prolonged symptoms termed long coronavirus disease (COVID), yet disease phenotypes and mechanisms are poorly understood1. Here we profiled 368 plasma proteins in 657 participants ≥3 months following hospitalization. Of these, 426 had at least one long COVID symptom and 233 had fully recovered. Elevated markers of myeloid inflammation and complement activation were associated with long COVID. IL-1R2, MATN2 and COLEC12 were associated with cardiorespiratory symptoms, fatigue and anxiety/depression; MATN2, CSF3 and C1QA were elevated in gastrointestinal symptoms and C1QA was elevated in cognitive impairment. Additional markers of alterations in nerve tissue repair (SPON-1 and NFASC) were elevated in those with cognitive impairment and SCG3, suggestive of brain–gut axis disturbance, was elevated in gastrointestinal symptoms. Severe acute respiratory syndrome coronavirus 2-specific immunoglobulin G (IgG) was persistently elevated in some individuals with long COVID, but virus was not detected in sputum. Analysis of inflammatory markers in nasal fluids showed no association with symptoms. Our study aimed to understand inflammatory processes that underlie long COVID and was not designed for biomarker discovery. Our findings suggest that specific inflammatory pathways related to tissue damage are implicated in subtypes of long COVID, which might be targeted in future therapeutic trials

    Semicomplete Multipartite Digraphs Whose Every Arc Is Contained in a Hamiltonian Path

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