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81.
Mycopathologia - Literature on COVID-19-associated pulmonary mucormycosis (CAPM) is sparse. Pulmonary artery pseudoaneurysm (PAP) is an uncommon complication of pulmonary mucormycosis (PM), and...  相似文献   
82.
Synthesis of several enantiomerically pure unsaturated bicyclo[3.3.1]nonane and related brexane (tricyclo[4.3.0.03,7]nonane) derivatives bearing exocyclic benzylidene substituents from readily available (+)‐(1S,5S)‐bicyclo[3.3.1]nonane‐2,6‐dione was accomplished. Molecular geometry and chiroptical properties of compounds with enone and styrene chromophores were studied by X‐ray diffraction analysis, molecular modeling, and circular dichroism (CD) spectroscopy. Difunctional 3,7‐dibenzylidenebicyclo[3.3.1]nonanes, such as 2 and 7 , 8 , 9 , exhibited intense CD couplets, arising from the exciton coupling between the two unsaturated chromophores. The observed negative sign of the exciton couplets is congruent with the negative twist (negative chirality) defined by the two interacting transition dipoles. The sign of the Cotton effect corresponding to the π→π* transitions in the CD spectra of monoenone 4 and tricyclic brexane acetate 11 was correlated with the intrinsic dissymmetry (helicity) of the styrene chromophore. Chirality 27:728–737, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
83.
Two different nematodes were isolated from the bark of Albizia lebbeck trees; one from insect infested and another from noninfested, healthy tree. Based on the biological, morphological, and molecular evidences, the nematodes are described as Deladenus albizicus n. sp. and D. processus n. sp. (Nematoda: Hexatylina). Deladenus albizicus n. sp., isolated from insect-infested tree, multiplied on the fungus Nigrospora oryzae. Myceliophagous females of this nematode reproduced by parthenogenesis and spermathecae were indistinct. Infective females, readily produced in the cultures, are dorsally curved. Only one type of males containing small-sized sperms in their genital tracts were produced in the culture. Myceliophagous females: L = 0.75 to 1.71 mm, a = 32.3 to 50.8, b = 9.3 to 11.2, b’ = 5.2 to 7.3, c = 27.2 to 35.6, V = 91.0 to 93.3, c’ = 2.0 to 2.9, stylet = 11 to 12 µm, excretory pore in the region of median pharyngeal bulb, 43 to 47 µm anterior to hemizonid. Deladenus processus n. sp., isolated from bark of healthy A. lebbeck tree, was cultured on Alternaria alternata. Myceliophagous females reproduced by amphimixis and their spermathecae contained rounded sperms. Infective females were never produced, even in old cultures. Myceliophagous females: L = 0.76 to 0.99 mm, a = 34 to 49, b = 13.3 to 17.7, b’ = 3.8 to 5.8, c = 19.6 to 22.8, V = 92.2 to 93.5, c’ = 2.7 to 3.5, stylet = 6 to 7 µm, excretory pore in the proximity of hemizonid, tail conoid, tapering from both sides to a long pointed central process. It is proposed to classify Deladenus species in three groups: durus, siricidicola, and laricis groups based on female and spermatogonia dimorphism, mode of reproduction, and insect parasitism.  相似文献   
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Parkinson’s disease (PD) is a chronic neurodegenerative disorder characterized by the loss of dopamine neurons in the substantia nigra, decreased striatal dopamine levels, and consequent extrapyramidal motor dysfunction. Recent evidence indicates that cyclin-dependent kinase 5 (Cdk5) is inappropriately activated in several neurodegenerative conditions, including PD. To date, strategies to specifically inhibit Cdk5 hyperactivity have not been successful without affecting normal Cdk5 activity. Previously we reported that TFP5 peptide has neuroprotective effects in animal models of Alzheimer’s disease. Here we show that TFP5/TP5 selective inhibition of Cdk5/p25 hyperactivation in vivo and in vitro rescues nigrostriatal dopaminergic neurodegeneration induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP/MPP+) in a mouse model of PD. TP5 peptide treatment also blocked dopamine depletion in the striatum and improved gait dysfunction after MPTP administration. The neuroprotective effect of TFP5/TP5 peptide is also associated with marked reduction in neuroinflammation and apoptosis. Here we show selective inhibition of Cdk5/p25 ­hyperactivation by TFP5/TP5 peptide, which identifies the kinase as a potential therapeutic target to reduce neurodegeneration in Parkinson’s disease.  相似文献   
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Tang TT  Zhu ZF  Wang J  Zhang WC  Tu X  Xiao H  Du XL  Xia JH  Dong NG  Su W  Xia N  Yan XX  Nie SF  Liu J  Zhou SF  Yao R  Xie JJ  Jevallee H  Wang X  Liao MY  Shi GP  Fu M  Liao YH  Cheng X 《PloS one》2011,6(9):e24272

Objective

Animal studies suggest that regulatory T (Treg) cells play a beneficial role in ventricular remodeling and our previous data have demonstrated defects of Treg cells in patients with chronic heart failure (CHF). However, the mechanisms behind Treg-cell defects remained unknown. We here sought to elucidate the mechanism of Treg-cell defects in CHF patients.

Methods and Results

We performed flow cytometry analysis and demonstrated reduced numbers of peripheral blood CD4+CD25+FOXP3+CD45ROCD45RA+ naïve Treg (nTreg) cells and CD4+CD25+FOXP3+CD45RO+CD45RA memory Treg (mTreg) cells in CHF patients as compared with non-CHF controls. Moreover, the nTreg/mTreg ratio (p<0.01), CD4+CD25+FOXP3+CD45RO CD45RA+CD31+ recent thymic emigrant Treg cell (RTE-Treg) frequency (p<0.01), and T-cell receptor excision circle levels in Treg cells (p<0.01) were lower in CHF patients than in non-CHF controls. Combined annexin-V and 7-AAD staining showed that peripheral Treg cells from CHF patients exhibited increased spontaneous apoptosis and were more prone to interleukin (IL)-2 deprivation- and CD95 ligand-mediated apoptosis than those from non-CHF individuals. Furthermore, analyses by both flow cytometry and real-time polymerase chain reaction showed that Treg-cell frequency in the mediastinal lymph nodes or Foxp3 expression in hearts of CHF patients was no higher than that of the non-CHF controls.

Conclusion

Our data suggested that the Treg-cell defects of CHF patients were likely caused by decreased thymic output of nascent Treg cells and increased susceptibility to apoptosis in the periphery.  相似文献   
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