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1.
Rachana R. Borkute Sren Woelke Gang Pei Anca Dorhoi 《International journal of molecular sciences》2021,22(9)
Neutrophils readily infiltrate infection foci, phagocytose and usually destroy microbes. In tuberculosis (TB), a chronic pulmonary infection caused by Mycobacterium tuberculosis (Mtb), neutrophils harbor bacilli, are abundant in tissue lesions, and their abundances in blood correlate with poor disease outcomes in patients. The biology of these innate immune cells in TB is complex. Neutrophils have been assigned host-beneficial as well as deleterious roles. The short lifespan of neutrophils purified from blood poses challenges to cell biology studies, leaving intracellular biological processes and the precise consequences of Mtb–neutrophil interactions ill-defined. The phenotypic heterogeneity of neutrophils, and their propensity to engage in cellular cross-talk and to exert various functions during homeostasis and disease, have recently been reported, and such observations are newly emerging in TB. Here, we review the interactions of neutrophils with Mtb, including subcellular events and cell fate upon infection, and summarize the cross-talks between neutrophils and lung-residing and -recruited cells. We highlight the roles of neutrophils in TB pathophysiology, discussing recent findings from distinct models of pulmonary TB, and emphasize technical advances that could facilitate the discovery of novel neutrophil-related disease mechanisms and enrich our knowledge of TB pathogenesis. 相似文献
2.
Carmen de Jesús-Gil Lídia Sans-de San Nicols Ester Ruiz-Romeu Marta Ferran Laura Soria-Martínez Irene García-Jimnez Anca Chiriac Josep Manel Casanova-Seuma Josep Manel Fernndez-Armenteros Sherry Owens Antonio Celada Michael D. Howell Ramn María Pujol Luis Francisco Santamaria-Babí 《International journal of molecular sciences》2021,22(4)
Candida albicans (CA) infections have been associated with psoriasis onset or disease flares. However, the integrated immune response against this fungus is still poorly characterized in psoriasis. We studied specific immunoglobulins in plasma and the CA response in cocultures of circulating memory CD45RA− cutaneous lymphocyte antigen (CLA)+/− T cell with autologous epidermal cells from plaque and guttate psoriasis patients (cohort 1, n = 52), and also healthy individuals (n = 17). A complete proteomic profile was also evaluated in plaque psoriasis patients (cohort 2, n = 114) regarding their anti-CA IgA levels. Increased anti-CA IgA and IgG levels are present in the plasma from plaque but not guttate psoriasis compared to healthy controls. CA cellular response is confined to CLA+ T cells and is primarily Th17. The levels of anti-CA IgA are directly associated with CLA+ Th17 response in plaque psoriasis. Proteomic analysis revealed distinct profiles in psoriasis patients with high anti-CA IgA. C-C motif chemokine ligand 18, chitinase-3-like protein 1 and azurocidin were significantly elevated in the plasma from plaque psoriasis patients with high anti-CA levels and severe disease. Our results indicate a mechanism by which Candida albicans exposure can trigger a clinically relevant IL-17 response in psoriasis. Assessing anti-CA IgA levels may be useful in order to evaluate chronic psoriasis patients. 相似文献
3.
4.
Josa. Trujillo-Quijano Delia B. Rodriguez-Amaya W. Esteves Gerhard F. Plonis 《European Journal of Lipid Science and Technology》1990,92(6):222-226
In oils extracted from fresh and sterilized palm fruits (Elaeis guineensis, Jacq. tenera, dura dumpy and psifera and E. oleifera), cis-phytofluene, 13-cis-α-carotene, α-carotene, 13-cis-β-carotene, β-carotene, 9-cis-β-carotene, σ-carotene, zeaxanthin, --cryptoxanthin, poly-cis-lycopene, mono-lycopene and lycopene, were identified and quantified by normal phase open column chromatography (stepwise-elution), TLC, UV/Vis spectroscopy and specific chemical reactions. The sum of α- and β-carotene in all samples analysed was higher than 80% of the total carotenoid content, while the α/β-carotene ratios were W.9, 1/11.1, 1/22 and V2.6 for oils extracted from fresh fruits of dura dumpy, psifera, tenera and E. oleifera, respectively. Total carotenoid contents (pg/g) and vitamin A values (R. E./100 g) of these samples were 1 120.7 and 12 404 for dura dumpy, 283.2 and 3612 for psifera, 660.5 and 7630 for tenera and 1576.8 and 21691 for E. oleifera. The sterilization of fruits (127°C × 35 min.) resulted in isomerization of pigments and reduction of vitamin A values of approximately 45% and 25%, respectively. 相似文献
5.
The incorporation of [1-14C] acetate into fatty acids by cultured epimastigotes ofTrypanosoma cruzi was studied. After 8, 24, and 48 hr incubation with labeled precursor, up to 2.8% of the initial radioactivity added to the
medium was found in theT. cruzi long chain fatty acids. Saturated (16∶0 and 18∶0), monounsaturated (18∶1ω9), and diunsaturated (18∶2ω6) fatty acids were
synthesized. Both the pattern of incorporation of labeled acetate into the fatty acids and the decarboxylation ratios found
suggest that de novo synthesis of fatty acids has taken place. 相似文献
6.
The chemical shift difference between signals of C() and C() of unsaturated ketones, , which we used before to measure acid strengths, has now been used to evaluate the hydrogen bond donor ability of solvents which are not acidic enough to hydronate the indicator. For such solvents there is no general correlation between H-bond donor ability and acid strength: hexa-fluoroisopropanol is a much weaker acid than acetic acid, but it is a stronger H-bond donor. The method can be applied to evaluate the H-bonding properties of solid surfaces, and it was thus found that silica gel has a much stronger H-bond donor ability than methanol or acetic acid. 相似文献
7.
Inspired by the Multiplicative Exponential fragment of Linear Logic, we define a framework called the prismoid of resources where each vertex is a language which refines the λ-calculus by using a different choice to make explicit or implicit (meta-level) the definition of the contraction, weakening, and substitution operations. For all the calculi in the prismoid we show simulation of β-reduction, confluence, preservation of β-strong normalisation and strong normalisation for typed terms. Full composition also holds for all the calculi of the prismoid handling explicit substitutions. The whole development of the prismoid is done by making the set of resources a parameter of the formalism, so that all the properties for each vertex are obtained as a particular case of the general abstract proofs. 相似文献
8.
Nikolaj S. Bjørner Anca Browne Michael A. Colón Bernd Finkbeiner Zohar Manna Henny B. Sipma Tomás E. Uribe 《Formal Methods in System Design》2000,16(3):227-270
We review a number of formal verification techniques supported by STeP, the Stanford Temporal Prover, describing how the tool can be used to verify properties of several versions of the Bakery Mutual exclusion algorithm for mutual exclusion. We verify the classic two-process algorithm and simple variants, as well as an atomic parameterized version. The methods used include deductive verification rules, verification diagrams, automatic invariant generation, and finite-state model checking and abstraction. 相似文献
9.
Delia Neuman 《Computers and the Humanities》1991,25(4):239-246
Delia Neuman is an assistant professor in the College of Library and Information Services at the University of Maryland, College Park. She has written several articles on the use of naturalistic inquiry to study electronic environments, including two published in Educational Technology Research and Development: Naturalistic Inquiry and Computer-Based Instruction: Rationale, Procedures and Potential (Spring 1989) and Learning Disabled Students' Interactions with Commercial Courseware: A Naturalistic Study (Spring 1991). She is currently involved in a study funded by the American Library Association to use naturalistic methods to investigate high school students' use of CD-ROM and online databases. 相似文献
10.
The study is focused on the external and internal mass transfers of lipids during their biodegradation process in a bioreactor with stationary basket bed of immobilized Bacillus spp. cells. By means of the lipid mass balance for a single particle of biocatalyst, considering the kinetic model adapted for the immobilized bacterial cells, specific mathematical models have been developed to estimate their mass flows in the liquid boundary layer surrounding the particle and inside the particle. The values of mass flows are significantly influenced by the internal diffusion velocity of lipids and the rate of their consumption, but also by the position inside the basket bed. These influences accumulated led to the appearance of a biological inactive region near the particle centre, its magnitude varying from 1.3 to 49.4% of the overall volume of particles. 相似文献