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101.
Toxic and genotoxic evaluation of six antibiotics on non-target organisms   总被引:10,自引:0,他引:10  
The ecotoxicity of the following six antibiotics on aquatic organisms was investigated: Erythromycin, Oxytetracyclin, Sulfamethoxazole, Ofloxacin, Lincomycin and Clarithromycin. Bioassays were performed on bacteria, algae, rotifers, microcrustaceans and fish to assess acute and chronic toxicity, while SOS Chromotest and Ames test were used to detect the genotoxic potential of the investigated drugs. For risk assessment, the environmental impact was calculated by MEC/PNEC ratio using the available data from the literature regarding their occurrence in the aquatic environment and the toxicity data obtained from the bioassays performed. The ecotoxicological results showed that acute toxicity was in the order of mg/L while, for the chronic data the antibiotics were bioactive at concentrations in the order of microg/L, mainly for the algae. Drugs investigated were one or two order of magnitude less active against rotifers and crustaceans. Ofloxacin was the only genotoxic compound and Sulfamethoxazole, Ofloxacin and Lincomycin were mutagenic. As for environmental risk, the macrolides were found to be the most harmful for the aquatic environment.  相似文献   
102.
Light chain amyloidosis (AL) is caused by the aberrant overproduction of immunoglobulin light chains (LCs). The resulting abnormally high LC concentrations in blood lead to deposit formation in the heart and other target organs. Organ damage is caused not only by the accumulation of bulky amyloid deposits, but extensive clinical data indicate that circulating soluble LCs also exert cardiotoxic effects. The nematode C. elegans has been validated to recapitulate LC soluble toxicity in vivo, and in such a model a role for copper ions in increasing LC soluble toxicity has been reported. Here, we applied microscale thermophoresis, isothermal calorimetry and thermal melting to demonstrate the specific binding of Cu2+ to the variable domain of amyloidogenic H7 with a sub-micromolar affinity. Histidine residues present in the LC sequence are not involved in the binding, and yet their mutation to Ala reduces the soluble toxicity of H7. Copper ions bind to and destabilize the variable domains and induce a limited stabilization in this domain. In summary, the data reported here, elucidate the biochemical bases of the Cu2+-induced toxicity; moreover, they also show that copper binding is just one of the several biochemical traits contributing to LC soluble in vivo toxicity.  相似文献   
103.
Cancer immunotherapy has already shown significant improvements by combining different antibodies specific for distinct immune checkpoints, such as Ipilimumab and Nivolumab. Here, we tested combinatorial treatments of immunomodulatory antibodies, previously generated in our laboratory, for their effects on hPBMC activation, either upon stimulation with SEB or in co-cultures with tumor cells by cytokine secretion assays. We found that some of them showed additive or synergistic effects, and on the basis of these observations, we constructed, for the first time, four novel bispecific tribodies (TR), made up of a Fab derived from one anti-IC mAb and two scFvs derived from another mAb targeting a different IC. All four TRs cotargeting either programmed cell death protein 1 (PD-1) and Lymphocyte Activating 3 (LAG-3) or programmed death-ligand 1 (PD-L1) and LAG-3 retained binding affinity for their targets and the antagonistic effects of their parental mAbs, but some of them also showed an increased ability to induce lymphocyte activation and increased in vitro cytotoxicity against tumor cells compared to parental antibodies used either alone or in combinatorial treatments. Furthermore, none of the tribodies showed significant increased cytotoxicity on human cardiomyocytes. Considering that the tribody format reduces production costs (as only one construct provides the inhibitory effects of two antibodies), has an intermediate molecular size (100 kDa) which is well suited for both tumor penetration and an acceptable half-life, we think that these novel immunomodulatory TRBs have the potential to become precious tools for therapeutic applications, particularly in monotherapy-resistant cancer patients.  相似文献   
104.
The prognosis of invasive cervical cancer (CC) remains poor, with a treatment approach that has remained the same for several decades. Lately, a better understanding of the interactions between the disease and the host immune system has allowed researchers to focus on the employment of immune therapy in various clinical settings. The most advanced strategy is immune checkpoint inhibitors (ICIs) with numerous phase II and III trials recently concluded with very encouraging results, assessing single agent therapy, combinations with chemotherapy and radiotherapy. Apart from ICIs, several other compounds have gained the spotlight. Tumor Infiltrating Lymphocytes (TILs) due to their highly selective tumoricidal effect and manageable adverse effect profile have received the FDA’s Breakthrough Therapy designation in 2019. The antibody drug conjugate (ADC) Tisotumab-Vedotin has shown activity in metastatic CC relapsed after at least one line of chemotherapy, with a phase III trial currently actively enrolling patients. Moreover, the deeper understanding of the ever-changing immune landscape of CC carcinogenesis has resulted in the development of active therapeutic vaccines. This review highlights the different immunotherapeutic strategies being explored reflects on what role immunotherapy might have in therapeutic algorithms of CC and addresses the role of predictive biomarkers.  相似文献   
105.
The growth of Lactobacillus plantarum WCFS1 and of its ΔccpA ery mutant, WCFS1-2, was compared in batch fermentations in a complex medium at controlled pH (6.5) and temperature (30°C) with or without aeration, in order to evaluate the effect of ccpA inactivation and aeration on growth, metabolism and stress resistance. Inactivation of ccpA and, to a lesser extent, aeration, significantly affected growth, expression of proteins related to pyruvate metabolism and stress, and tolerance to heat, oxidative and cold/starvation stresses. The specific growth rate of the mutant was ca. 60% of that of the wild type strain. Inactivation of ccpA and aerobic growth significantly affected yield and production of lactic and acetic acid. Stationary phase cells were more stress tolerant than exponential phase cells with little or no effect of inactivation of ccpA or aeration. On the other hand, for exponential phase cells inactivation of ccpA impaired both heat stress and cold/starvation stress, but increased oxidative stress tolerance. For both strains, aerobically grown cells were more tolerant of stresses. Evidence for entry in a viable but non-culturable status upon prolonged exposure to cold and starvation was found. Preliminary results of a differential proteomic study further confirmed the role of ccpA in the regulation of carbohydrate catabolism and class I stress response genes and allow to gain further insight on the role of this pleiotropic regulator in metabolism and stress. This is the first study in which the impact of aerobic growth on stress tolerance of L. plantarum is evaluated. Although aerobic cultivation in batch fermentations does not improve growth it does improve stress tolerance, and may have significant technological relevance for the preservation of starter and probiotic cultures.  相似文献   
106.
In order to study the composition of the lactic acid bacteria (LAB) community of sourdoughs used for the manufacture of Altamura bread, a traditional durum wheat bread produced in Apulia (Southern Italy), 111 strains of LAB were isolated and characterized. The phenotypic characterization of the isolates, carried out using a set of 29 tests, allowed the identification of 15 clusters at the 80% similarity level by hierarchical cluster analysis. Of the isolates, 88% were identified as facultatively heterofermentative LAB (Lactobacillus plantarum, Lb. paracasei, Lb. casei) and 12% as heterofermentative LAB (Lb. brevis, Leuconostoc mesenteroides). SDS-PAGE profiles of whole cell proteins of 68 strains confirmed the identification. Both the diversity and structure of the lactic microflora for sourdoughs for Altamura bread varied among samples.  相似文献   
107.
Four novel straight-chain polyacetylenic alcohols were isolated from a marine ascidian (Phylum Chordata, subphyllum Urochordata) collected off Vigo, along the Atlantic coast of northwestern Spain. The chemical structures, which exhibit an uncommon dienyne group, were characterized by spectroscopic methods, mainly mono- and bi-dimensional NMR. This is the first finding of acetylenic lipids from an organism belonging to phylum Chordata.  相似文献   
108.
MicroRNAs (miRNA) are key regulators of gene expression, controlling different biological processes such as cellular development, differentiation, proliferation, metabolism, and apoptosis. The relationships between miRNA expression and the onset and progression of different diseases, such as tumours, cardiovascular and rheumatic diseases, and neurological disorders, are well known. A nanotechnology-based approach could match miRNA delivery and detection to move beyond the proof-of-concept stage. Different kinds of nanotechnologies can have a major impact on the diagnosis and treatment of miRNA-related diseases such as cancer. Developing novel methodologies aimed at clinical practice represents a big challenge for the early diagnosis of specific diseases. Within this context, nanotechnology represents a wide emerging area at the forefront of research over the last two decades, whose potential has yet to be fully attained. Nanomedicine, derived from nanotechnology, can exploit the unique properties of nanometer-sized particles for diagnostic and therapeutic purposes. Through nanomedicine, specific treatment to counteract only cancer-cell proliferation will be improved, while leaving healthy cells intact. In this review, we dissect the properties of different nanocarriers and their roles in the early detection and treatment of cancer.  相似文献   
109.
Iron is necessary for essential processes in every cell of the body, but the erythropoietic compartment is a privileged iron consumer. In fact, as a necessary component of hemoglobin and myoglobin, iron assures oxygen distribution; therefore, a considerable amount of iron is required daily for hemoglobin synthesis and erythroid cell proliferation. Therefore, a tight link exists between iron metabolism and erythropoiesis. The liver-derived hormone hepcidin, which controls iron homeostasis via its interaction with the iron exporter ferroportin, coordinates erythropoietic activity and iron homeostasis. When erythropoiesis is enhanced, iron availability to the erythron is mainly ensured by inhibiting hepcidin expression, thereby increasing ferroportin-mediated iron export from both duodenal absorptive cells and reticuloendothelial cells that process old and/or damaged red blood cells. Erythroferrone, a factor produced and secreted by erythroid precursors in response to erythropoietin, has been identified and characterized as a suppressor of hepcidin synthesis to allow iron mobilization and facilitate erythropoiesis.  相似文献   
110.
Neuropathic pain is a characteristic feature of small fiber neuropathy (SFN), which in 18% of the cases is caused by genetic variants in voltage-gated sodium ion channels. In this study, we assessed the role of fifteen other ion channels in neuropathic pain. Patients with SFN (n = 414) were analyzed for ANO1, ANO3, HCN1, KCNA2, KCNA4, KCNK18, KCNN1, KCNQ3, KCNQ5, KCNS1, TRPA1, TRPM8, TRPV1, TRPV3 and TRPV4 variants by single-molecule molecular inversion probes–next-generation sequencing. These patients did not have genetic variants in SCN3A, SCN7A-SCN11A and SCN1B-SCN4B. In twenty patients (20/414, 4.8%), a potentially pathogenic heterozygous variant was identified in an ion-channel gene (ICG). Variants were present in seven genes, for two patients (0.5%) in ANO3, one (0.2%) in KCNK18, two (0.5%) in KCNQ3, seven (1.7%) in TRPA1, three (0.7%) in TRPM8, three (0.7%) in TRPV1 and two (0.5%) in TRPV3. Variants in the TRP genes were the most frequent (n = 15, 3.6%), partly in patients with high mean maximal pain scores VAS = 9.65 ± 0.7 (n = 4). Patients with ICG variants reported more severe pain compared to patients without such variants (VAS = 9.36 ± 0.72 vs. VAS = 7.47 ± 2.37). This cohort study identified ICG variants in neuropathic pain in SFN, complementing previous findings of ICG variants in diabetic neuropathy. These data show that ICG variants are central in neuropathic pain of different etiologies and provides promising gene candidates for future research.  相似文献   
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