Synthesis of Oligonucleotide Conjugates and Phosphorylated Nucleotide Analogues: An Improvement to a Solid Phase Synthetic Approach

An improvement to our solid phase strategy to generate pharmacologically interesting molecule libraries is proposed here. The synthesis of newo-chlorophenol-functionalised solid supports with very high loading (0.18–0.22 meq/g for control pore glass (CPG) and 0.25–0.50 meq/g for TG) is reported. To test the efficiency of these supports, we prepared nucleotide and oligonucleotide models, and their coupling yields and the purity of the crude detached materials were comparable to previously available results. These supports allow the facile and high-yield preparation of highly pure phosphodiester and phosphoramidate monoester nucleosides, conjugated oligonucleotides, and other yet unexplored classes of phosphodiester and phosphoramidate molecules

New 23-phosphodiester derivatives of Silibin and DHS: synthesis and preliminary evaluation of antioxidant properties

Silybin is the major flavonolignan of silymarin which is widely used as a natural remedy for the treatment of cirrhosis, chronic hepatitis, and liver diseases associated with alcohol consumption and exposure to environmental toxins. Different studies recently made on the antiradical activity of silybin and DHS have elucidated the functional groups responsible for this activity. The results suggest that the C-23 position could be a site for useful modifications aimed to improve the bioactivity of silybin and/or DHS analogues. Recently we describe an efficient synthetic strategy to obtain a variety of new silybin and 2,3-dehydrosilybin (DHS) derivatives in which the 23-hydroxyl group was converted to a sulfate, phosphodiester, or amine group, using a solution-phase approach. The antioxidant properties of the new compounds were evaluated in a cellular model in vivo and most of them displayed an antioxidant activity comparable or higher to silybin and DHS. These results confirmed the assumption that modifications in position C–23 do not affect the radical scavenging activity of these analogues. With the final goal to expand the repertoire of silybin and DHS C-23 modified, we describe here the synthesis and preliminary evaluation of antioxidant properties of a variety of new silybin and DHS conjugated with different labels through a phosphodiester bond The antioxidative properties of the above-synthesized compounds were determined by free radical scavenging (DPPH) assay

Synthesis and characterization of a mini-library of new conjugated d(TGGGAG) oligonucleotides with potential anti-HIV activity.

In the search for ODNs endowed with relevant antiviral properties, Hotoda and coworkers investigated a series of G-quadruplex-forming ODNs, finally focusing on modified d(TGGGAG) ODNs conjugated with aromatic residues at the 5-end. These were found to exhibit potent anti-HIV activity associated with low cytotoxicity when carrying at the 5′-end bulky aromatic residues. Recently we described a general approach to obtain a mini library of new d(TGGGAG) ODNs, conjugated with different aromatic groups at the 5’-end through a phosphodiester bond. Several modified sequences showed pronounced anti-HIV-1 activity and they showed high binding affinities for the HIV-1 envelope gp120 and gp41. In these structures the 5-end residues play a major role on the G-quadruplex stability, dramatically enhancing stability of the quadruplex complexes (Tm>20°C). With the final goal to expand the repertoire of accessible end-modified G-rich ODNs, and to get a more complete picture of their structure-activity relationships, we describe herein the synthesis and characterization of a mini-library of new d(5’TGGGAG3’) carrying hydrophobic groups at the 5’-end and 2-hydroxyethylphosphate group at the 3'-end, connected through phosphodiester and phosphoramidate bonds, respectively. In order to study the influence of the conjugation at the ends of the oligonucleotide chains on their ability to form quadruplex structures, a CD analysis was undertaken on the conjugated oligomers in comparison with the corresponding unmodified d(TGGGAG) oligomer

Measles Outbreak Among Healthcare Professionals: Operational Response and Remedial Measures

Given the numerous cases recorded in 2017, a descriptive epidemiological study was conducted in the Viterbo Local Health Unit (LHU) area, Italy. Hospital Discharge Sheets (HDSs) and the notifications of infectious diseases (NOIDs) were used.We were able to trace the distribution of the disease both in the general population and, in particular, among the staff of Belcolle Hospital in Viterbo. In 2017, 50 cases of measles were detected among the population in the area of Viterbo. Of these, 10 concerned healthcare professionals and 3 employees of the Viterbo LHU.Due to the education and information campaign on the measles, mumps, and rubella (MMR) vaccine and the close monitoring of the vaccination coverage among the employees of the hospital (performed for the first time), only 4 cases were registered from January 1, 2018 to December 31, 2018 in the same area, and no healthcare workers were involved

siRNAs bearing aromatic residues in the 3’-overhang region

RNA interference (RNAi) is a biological process whereby small interfering RNA (siRNA) and microRNA (miRNA) silence gene expression in a sequence-specific manner. These effectors regulate gene expression through the RNA-induced silencing complex (RISC). It has been suggested that RISC preferentially selects and incorporates one of two strands of the siRNA duplex depending on its thermodynamic features and that the off-target effects of siRNAs can be correlated to the Tm of the duplex. The problem of unwanted incorporation of the passenger strand into RISC could be address altering the thermodynamic asymmetry of the duplex by using specific chemical modifications. Structural studies have revealed that the 3’-overhang region of the guide strand of siRNA is recognized by the PAZ domain and is accommodated into its hydrophobic binding pocket. We expected that aromatic-based modifications in 3’-overhang would enhance RISC selection of antisense strands of siRNA duplexes, reducing off-target effects induced by sense strands. In this study, we report the synthesis of siRNAs bearing diphenylpropylamine, tyramine and tryptamine units at the 3’-end of sense and antisense strands. We found thermodynamic stability of the conjugates was increased by these modifications. Furthermore, but not surprisingly, the modified duplexes were found to retain RNA-like A-type conformation. We also assessed the nuclease resistance of the modified siRNAs and found it was similar to those of unmodified siRNAs. These results prompted us to investigate the silencing activity of the siRNAs possessing the aromatic moiety in the 3’-end by in vitro experiments in mammalian cells

Minimally invasive video-assisted thyroidectomy (MIVAT)

Minimally invasive video-assisted thyroidectomy (MIVAT) was first described in 1999 and it has become a widespread technique performed worldwide. Although initially limited to benign thyroid nodules, MIVAT was progressively adopted for all types of thyroid diseases, while remaining within the selection criteria. It is reported that, in selected cases, MIVAT is comparable to standard open thyroidectomy (SOT) in terms of oncologic radicality, time, costs and complications rate, with the advantage of a better cosmetic result and a lower post-operative pain

Harpin oligonucleotides forming G-quadruplexes: new aptamers with potential anti-HIV activity

Several G-rich synthetic oligodeoxyribonucleotides (ODNs) have shown promising biological properties, ranging from anticancer to anti-HIV activities. G-quadruplex formation was found to be a crucial prerequisite in determining these biological effects. Aptamers exhibiting anti-HIV activity represent an important class of potential therapeutics. Recently we described the synthesis and characterization of new d(TGGGAG) ODNs, conjugated with different aromatic groups at the 5’-end through a phosphodiester bond. The modified sequences showed a parallel stranded tetramolecular G-quadruplexes CD profile and a pronounced anti-HIV-1 activity. Herein, with the aim to use d(TGGGAG) as a lead sequence for a more effective anti-HIV agent, we propose the fully automated synthesis of new ODNs containing two d(TGGGAG) sequences whose 3-ends are joint by an hexaethylenglycole loop. CD analysis was undertaken on the 3’-3’ linked d(TGGGAG) hairpins in comparison with the corresponding unmodified oligomers. Besides, in order to study the influence of the conjugation at the ends of the harpin chains on their ability to stabilize quadruplex structures and on their anti-HIV activity, different conjugated oligomers have been studied

Cavity-based lymphomas: challenges and novel concepts. A report of the 2022 EA4HP/SH lymphoma workshop

The 2022 European Association for Haematopathology/Society for Hematopathology lymphoma workshop session on cavity-based lymphomas included sixty-eight cases in seven sections. The disease entities discussed include primary effusion lymphomas (PEL), extracavitary primary effusion lymphomas and confounding entities (ECPEL), HHV8-negative B-lineage lymphomas-effusion based (EBV-negative, EBV-positive, and plasmablastic types), diffuse large B-cell lymphoma associated with chronic inflammation, fibrin-associated diffuse large B-cell lymphoma (FA-DLBCL), breast implant-associated anaplastic large cell lymphoma (BIA-ALCL), and other lymphomas presenting as an effusion. All entities above are discussed; however, three are delved into greater detail given the challenges with classification: ECPEL, HHV8-negative effusion-based lymphomas, and FA-DLBCL. Cases exemplifying the diagnostic difficulty in differentiating ECPEL from HHV8-positive diffuse large B-cell lymphoma and germinotropic lymphoproliferative disorder were discussed. The more recently recognized effusion-based HHV8-negative large B-cell lymphoma is explored, with several cases submitted raising the question if this subset should be carved out as a specific entity, and if so, what should be the refining diagnostic criteria. Case submissions to the FA-DLBCL section yielded one of the largest case series to date, including classic cases, cases furthering the discussion on disease sites and prognosis, as well as novel concepts to be considered in this entity. The 2022 EA4HP/SH workshop cases allowed for further confirmation of the characteristics of some of the more historically accepted cavity-based lymphomas, as well as further inquiry and debate on relatively new or evolving entities

Impact of Previous Nephrectomy on Clinical Outcome of Metastatic Renal Carcinoma Treated With Immune-Oncology: A Real-World Study on Behalf of Meet-URO Group (MeetUro-7b)

Background: Immune-Oncology (IO) improves Overall Survival (OS) in metastatic Renal Cell Carcinoma (mRCC). The prognostic impact of previous Cytoreductive Nephrectomy (CN) and radical nephrectomy (RN), with curative intent, in patients treated with IO is not well defined. The aim of our paper is to evaluate the impact of previous nephrectomy on outcome of mRCC patients treated with IO. Methods: 287 eligible patients were retrospectively collected from 16 Italian referral centers adhering to the MeetUro association. Patients treated with IO as second and third line were included, whereas patients treated with IO as first line were excluded. Kaplan–Meier method and log-rank test were performed to compare Progression Free Survival (PFS) and OS between groups. In our analysis, both CN and RN were included. The association between nephrectomy and other variables was analyzed in univariate and multivariate setting using the Cox proportional hazard model. Results: 246/287 (85.7%) patients had nephrectomy before IO treatment. Median PFS in patients who underwent nephrectomy (246/287) was 4.8 months (95%CI 3.9–5.7) vs 3.7 months (95%CI 1.9–5.5) in patients who did not it (HR log rank 0.78; 95%CI 0.53 to 1.15; p = 0.186). Median OS in patients who had previous nephrectomy (246/287) was 20.9 months (95%CI 17.6–24.1) vs 13 months (95%CI 7.7–18.2) in patients who did not it (HR log rank 0.504; 95%CI 0.337 to 0.755; p = 0.001). In the multivariate model, nephrectomy showed a significant association with OS (HR log rank 0.638; 95%CI 0.416 to 0.980), whereas gland metastases were still associated with better outcome in terms of both OS (HR log rank 0.487; 95%CI 0.279 to 0.852) and PFS (HR log rank 0.646; 95%CI 0.435 to 0.958). Conclusions: IO treatment, in patients who had previously undergone nephrectomy, was associated with a better outcome in terms of OS. Further prospective trials would assess this issue in order to guide clinicians in real word practice