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991.
Abstract OBSERVATIONS ON THE CARYOLOGY OF GENNARIA DIPHYLLA (LINK) PARL. (COELOGLOSSUM DIPHYLLUM FIORI) — Some caryological characters of Gennaria diphylla (Link) Parl, have been here investigated. Chromosome counts from somatic metaphases show a 34 chromosomes diploid set; the resting nuclei have been classified as half-reticulated with chromocenters (« noyaux semi-reticulé à chromocentres » according to Delay's classification); in prophases we have noticed that chromocenters often appear like prochromosomes. The chromosome number 17 (2n = 34) is new for the Ophrydinae. The interest of this research lies in the fact that the species here dealt with has been differently classified by various Authors. 相似文献
992.
Priyanka Tripathi Haihong Guo Alice Dreser Alfred Yamoah Antonio Sechi Christopher Marvin Jesse Istvan Katona Panagiotis Doukas Stefan Nikolin Sabrina Ernst Eleonora Aronica Hannes Glaß Andreas Hermann Harry Steinbusch Alfred C. Feller Markus Bergmann Dick Jaarsma Joachim Weis Anand Goswami 《Cell death & disease》2021,12(5)
Mutations in RNA binding proteins (RBPs) and in genes regulating autophagy are frequent causes of familial amyotrophic lateral sclerosis (fALS). The P56S mutation in vesicle-associated membrane protein-associated protein B (VAPB) leads to fALS (ALS8) and spinal muscular atrophy (SMA). While VAPB is primarily involved in the unfolded protein response (UPR), vesicular trafficking and in initial steps of the autophagy pathway, the effect of mutant P56S-VAPB on autophagy regulation in connection with RBP homeostasis has not been explored yet. Examining the muscle biopsy of our index ALS8 patient of European origin revealed globular accumulations of VAPB aggregates co-localised with autophagy markers LC3 and p62 in partially atrophic and atrophic muscle fibres. In line with this skin fibroblasts obtained from the same patient showed accumulation of P56S-VAPB aggregates together with LC3 and p62. Detailed investigations of autophagic flux in cell culture models revealed that P56S-VAPB alters both initial and late steps of the autophagy pathway. Accordingly, electron microscopy complemented with live cell imaging highlighted the impaired fusion of accumulated autophagosomes with lysosomes in cells expressing P56S-VAPB. Consistent with these observations, neuropathological studies of brain and spinal cord of P56S-VAPB transgenic mice revealed signs of neurodegeneration associated with altered protein quality control and defective autophagy. Autophagy and RBP homeostasis are interdependent, as demonstrated by the cytoplasmic mis-localisation of several RBPs including pTDP-43, FUS, Matrin 3 which often sequestered with P56S-VAPB aggregates both in cell culture and in the muscle biopsy of the ALS8 patient. Further confirming the notion that aggregation of the RBPs proceeds through the stress granule (SG) pathway, we found persistent G3BP- and TIAR1-positive SGs in P56S-VAPB expressing cells as well as in the ALS8 patient muscle biopsy. We conclude that P56S-VAPB-ALS8 involves a cohesive pathomechanism of aberrant RBP homeostasis together with dysfunctional autophagy.Subject terms: Mechanisms of disease, Amyotrophic lateral sclerosis 相似文献
993.
G Di Cara MG Berioli A Biscarini C Soldani P Abate E Ugolini G Allocca M Milioni 《Journal of medical case reports》2012,6(1):299
ABSTRACT: INTRODUCTION: Cow's milk allergy is the most frequent food allergy in Europe and western countries and shows a wide spectrum of clinical features, including atopic dermatitis and gastrointestinal disease. To the best of our knowledge, this report is the first to describe Kawasaki disease-like clinical features and echocardiographic alterations which resolved after a cow's milk-free diet. CASE PRESENTATION: We report a case of a 9-month-old Caucasian girl with atopic dermatitis who developed clinical features commonly present in Kawasaki disease (erythematous skin rash, non-exudative conjunctivitis, fissured lips and neck lymph nodes), together with mild echocardiographic alterations (perivascular brightness, pericardial effusion) in the absence of fever. These features resolved within 2 weeks after the beginning of a cow's milk-free diet. CONCLUSION: Kawasaki disease has recently been considered a possible risk factor for subsequent allergic disease secondary to immune dysfunction. This case report suggests that the immune-related alterations which are commonly present in allergic patients could be similar to the antigen-related immune response in Kawasaki disease and thus could lead to similar clinical features. 相似文献
994.
995.
Fabio Malavasi Eleonora Olivetti Claudio Milanese Angelo O. Carbonara 《Human genetics》1981,58(2):209-212
Summary A sample of healthy unrelated individuals (882 from Continental Italy and Sicily, and 139 from Sardinia) were typed for HLA and Bf polymorphisms. Bf gene frequencies in Continental Italy and Sicily show an intermediate position among European populations, with Lapps on one side and Basques on the other side; while a very peculiar pattern is observed among Sardinians, with an impressive similarity with French Basques and with the highest F1 gene frequency so far observed. The HLA: Bf gametic associations in Italy and Sardinia are also reported, which confirm the different ethnic background of these populations.This work was supported by Centro di Immunogenetica ed Istocompatibilità, C.N.R., Torino, Italy and by a grant of Ministero Pubblica Istruzione (M.P.I., Cap. 8551/1980). 相似文献
996.
Agostina Pietrantoni Eleonora Dofrelli Antonella Tinari Maria Grazia Ammendolia Simona Puzelli Concetta Fabiani Isabella Donatelli Fabiana Superti 《Biometals》2010,23(3):465-475
Influenza is one of the main plagues worldwide. The statistical likelihood of a new pandemic outbreak, together with the alarming
emergence of influenza virus strains that are resistant to available antiviral medications, highlights the need for new antiviral
drugs. Lactoferrin, a 80 kDa bi-globular iron-binding glycoprotein, is a pleiotropic factor with potent antimicrobial and
immunomodulatory activities. Although the antiviral effect of lactoferrin is one of its major biological functions, the mechanism
of action is still under debate. In this research, we have analyzed the effect of bovine lactoferrin (bLf) on Influenza A
virus infection in vitro. Our results showed that (i) Influenza virus infected cells died as a result of apoptosis, (ii) bLf
treatment inhibited programmed cell death by interfering with function of caspase 3, a major virus-induced apoptosis effector,
and (iii) bLf efficiently blocked nuclear export of viral ribonucleoproteins so preventing viral assembly. These results provide
further insights on the antiviral activity of bLf and suggest novel strategies for treatment of Influenza virus infection. 相似文献
997.
Eleonora Kumer Mario Berveglieri Marisa Cova Ida Magri Michela Mascis 《Aerobiologia》1996,12(3):197-200
The microbiological quality of indoor air is creating an increasing interest especially as far as places at risk such as hospitals,
clinics, medical and odontological surgeries are concerned. Working with the odontologists of our province we have been carrying
out a research aimed at preventing cross-infection in odontology. Data obtained from the microbiological analysis of the air
in 36 surgeries using S.A.S were discussed during the V National Congress of Aerobiology. During that congress the need of
setting a standardized technique of air sampling in indoor environments emerged and two routes have been identified: (1) the
gravimetric technique on open plate exposed for an hour close to the dental unit and (2) the use of the volumetric sampler
which gives qualitative data expressed as colonies forming units per cubic metre of air. However, both of these techniques
present some problems: using the first a loss of micro-organisms has been noticed due to the variability of the air fluxes
and the different weight of the biological particles; using the second one the bacterial charge is also undervalued, because
of the stress suffered by the bacteria with the use of the volumetric sampler. In the light of these statements we decided
to use both in dental surgeries to be able to compare the results obtained. Our project is expected to carry out at least
one inspection and the relative sampling (indoor air, water of the dental unit, air of the syringe, disinfectant solution,
surface tampons, biological test of sterility) in each dental surgery in the territory of our health Unit, located in Ferrara,
Northern Italy. 相似文献
998.
999.
Tania Velletri Yin Huang Yu Wang Qing Li Mingyuan Hu Ningxia Xie Qian Yang Xiaodong Chen Qing Chen Peishun Shou Yurun Gan Eleonora Candi Margherita Annicchiarico-Petruzzelli Massimiliano Agostini Huilin Yang Gerry Melino Yufang Shi Ying Wang 《Cell death and differentiation》2021,28(1):156
p53 plays a pivotal role in controlling the differentiation of mesenchymal stem cells (MSCs) by regulating genes involved in cell cycle and early steps of differentiation process. In the context of osteogenic differentiation of MSCs and bone homeostasis, the osteoprotegerin/receptor activator of NF-κB ligand/receptor activator of NF-κB (OPG/RANKL/RANK) axis is a critical signaling pathway. The absence or loss of function of p53 has been implicated in aberrant osteogenic differentiation of MSCs that results in higher bone formation versus erosion, leading to an unbalanced bone remodeling. Here, we show by microCT that mice with p53 deletion systemically or specifically in mesenchymal cells possess significantly higher bone density than their respective littermate controls. There is a negative correlation between p53 and OPG both in vivo by analysis of serum from p53+/+, p53+/−, and p53−/− mice and in vitro by p53 knockdown and ChIP assay in MSCs. Notably, high expression of Opg or its combination with low level of p53 are prominent features in clinical cancer lesion of osteosarcoma and prostate cancer respectively, which correlate with poor survival. Intra-bone marrow injection of prostate cancer cells, together with androgen can suppress p53 expression and enhance local Opg expression, leading to an enhancement of bone density. Our results support the notion that MSCs, as osteoblast progenitor cells and one major component of bone microenvironment, represent a cellular source of OPG, whose amount is regulated by the p53 status. It also highlights a key role for the p53-OPG axis in regulating the cancer associated bone remodeling.Subject terms: Cell biology, Pathogenesis 相似文献
1000.
Specific In Vitro Biological Activity of Snake Venom Myotoxins 总被引:1,自引:0,他引:1
Juan L. Brusés Juan Capaso Eleonora Katz Guillermo Pilar 《Journal of neurochemistry》1993,60(3):1030-1042
Abstract: Some snake venoms contain toxins that are reported to be selective for damaging muscle. This specificity can be used to design experiments intended to eliminate muscle. We studied the small myotoxins and fractions IV and V of Bothrops nummifer venom to evaluate their direct effect on cultured muscle cells, neurons, macrophages, and a fibroblast cell line. The small myotoxins, at 100 μg/ml for 2 h, had no effect in vitro, contrary to the in vivo applications. Fractions IV and V were both myotoxic and, at 100 μg/ml, destroyed all cell types. However, at 10 μg/ml the effects of fraction IV were more selective for muscle. Vacuolation of the sarcoplasmic reticulum and T-tubules was first seen in the poisoned muscles, without initial lesions in the nuclei, sarcolemma, mitochondria, and rough endoplasmic reticulum. Fractions IV and V have different toxic activity in cells other than muscles and are a mixture of two basic proteins (i and ii). Protein ii is predominant in fraction IV and protein i is predominant in fraction V. The toxic effects may be mediated by the formation of nonspecific ionic pores in the sarcolemma and/or T-tubule muscle membrane. 相似文献