319 research outputs found
Hydrolysis of 5-methylfuran-2-yl to 2,5-dioxopentanyl allows for stable bio-orthogonal proximity-induced ligation
Ligation methodologies featuring bio-orthogonal units and leading to the formation of a stable adduct are the ideal candidates for being applied in a biological context. However, most of the available strategies rely on highly reactive species that require careful handling, or on the activation of pro-reactive functional groups. We here report on a proximity-induced ligation reaction that relies on a stable 2,5-dione, that can be conveniently generated under acidic conditions from a 2,5-dialkylfuran building block, and hydrazine nucleophiles. This bio-orthogonal ligation, which proceeds under physiological conditions, does not require any stimulus or trigger and leads to the formation of a pyridazinium adduct that demonstrates excellent stability under harsh conditions (24 h at 90 °C). The reaction was applied to the formation of PNA-PNA adducts, DNA- and RNA-templated ligations, and for the formation of peptide-peptide adducts in solution. This convenient methodology was further implemented on plastic and glass surfaces to realize self-addressable covalent constructs
Beyond small molecules: Targeting G-quadruplex structures with oligonucleotides and their analogues
G-Quadruplexes (G4s) are widely studied secondary DNA/RNA structures, naturally occurring when G-rich sequences are present. The strategic localization of G4s in genome areas of crucial importance, such as proto-oncogenes and telomeres, entails fundamental implications in terms of gene expression regulation and other important biological processes. Although thousands of small molecules capable to induce G4 stabilization have been reported over the past 20 years, approaches based on the hybridization of a synthetic probe, allowing sequence-specific G4-recognition and targeting are still rather limited. In this review, after introducing important general notions about G4s, we aim to list, explain and critically analyse in more detail the principal approaches available to target G4s by using oligonucleotides and synthetic analogues such as Locked Nucleic Acids (LNAs) and Peptide Nucleic Acids (PNAs), reporting on the most relevant examples described in literature to date
O-136. Use of mini-Percoll and swim-up sperm preparation techniques in separating spermatozoa with chromatin packaging anomalies
X-linked heterochromatin distribution in the holocentric chromosomes of the green apple aphid Aphis pomi
Chromatin organization in the holocentric chromosomes of the green apple aphid Aphis pomi has been investigated at a cytological level after C-banding, NOR, Giemsa, fluorochrome staining and fluorescent in situ hybridization (FISH). C-banding technique showed that heterochromatic bands are exclusively located on X chromosomes. This data represents a peculiar feature that clearly contradicts the equilocal distribution of heterochromatin typical of monocentric chromosomes. Moreover, silver staining and FISH carried out with a 28S rDNA probe localized rDNA genes on one telomere of each X chromosome; CMA(3) staining reveals that these silver positive telomeres are, the only GC-rich regions among A. pomi heterochromatin, whereas all other C-positive bands are DAPI positive thus containing AT-rich DNA
Generalizability of Cardiovascular Safety Trials on SGLT2 Inhibitors to the Real World: Implications for Clinical Practice
Introduction: Following the US Food and Drug Administration (FDA) guidance on the evaluation of novel agents for the treatment of type 2 diabetes mellitus (T2DM), a number of cardiovascular outcomes safety trials (CVOTs) on sodium-glucose cotransporter-2 inhibitors (SGLT2i) have been conducted. These trials show similarities in study design and definition of primary endpoints, but differ in their eligibility criteria. The aim of the present study was to investigate the generalizability of CVOTs on SGLT2i to Italian adults with T2DM; we estimated the proportions of this patient population who would be eligible for enrollment in EMPA-REG OUTCOME (empagliflozin), CANVAS (canagliflozin), DECLARE-TIMI 58 (dapagliflozin), and VERTIS-CV (ertugliflozin) studies.
Methods: This observational, cross-sectional study was conducted in 222 Italian diabetes clinics. Data on 455,662 adult patients with T2DM seen during 2016 were analyzed against the published patient eligibility criteria for the four CVOTs. The current use of SGLT2i in potentially eligible patients was assessed.
Results: Among the population identified, the proportion of patients meeting major eligibility criteria was 11.7% for EMPA-REG OUTCOME, 29.4% for CANVAS, 55.9% for DECLARE-TIMI 58, and 12.8% for VERTIS-CV. Of the patients eligible for these CVOTs, only a minority (range 4.4-6.8%) was actually prescribed an SGLT2i. Compared with patients in the CVOTs, eligible patients in the real world showed older age and longer diabetes duration, lower BMI and HbA1c levels, lower prevalence of established cardiovascular and cerebrovascular disease, and higher rates of microvascular complications and peripheral arterial disease.
Conclusion: The percentage of patients potentially eligible for treatment with SGLT2i varies as a reflection of different eligibility criteria applied in the trials. A large number of patients that could benefit from SGLT2i in terms of not only cardiovascular protection but also renal protection do not receive the treatment
Sperm nuclear DNA damage and altered chromatin structure: effect on fertilization and embryo development
In the first part of this report we investigate whether chromatin anomalies in human spermatozoa can influence fertilization after intracytoplasmic sperm injection (ICSI). We have examined the sperm chromatin packaging quality using the chromomycin A3 (CMA3) fluorochrome and the presence of DNA damage in spermatozoa using in-situ nick translation. When comparing the spermatozoa of patients undergoing in-vitro fertilization (IVF) and ICSI distinct differences are evident in that ICSI males have a higher CMA3 fluorescence, indicating spermatozoa with loosely packed chromatin, and more spermatozoa containing endogenous DNA nicks. When examining the unfertilized oocytes of ICSI patients we found that men who had a high percentage of anomalies in their chromatin, i.e. >30% CMA3 fluorescence and >10% nicks, had more than double the number of unfertilized oocytes containing spermatozoa that had remained condensed. The observation that failed fertilized oocytes, injected with spermatozoa from patients with a higher percentage of sperm nuclear anomalies, contain more condensed spermatozoa indicates that a selection process against these spermatozoa may be in place at the time of fertilization. In the second part of the study we show that spare ICSI embryos have significantly lower rates of development to the blastocyst stage compared with those developed after routine IVF. These results show that a greater understanding of the molecular basis of male infertility is therefore needed to broaden our knowledge on the effect that abnormal spermatozoa have on fertilization and embryo developmen
Sperm chromatin anomalies can influence decondensation after intracytoplasmic sperm injection
In this study we investigated whether morphology and chromatin anomalies in human spermatozoa can influence fertilization after intracytoplasmic sperm injection (ICSI). We examined unfertilized oocytes, using the fluorochrome Hoechst 33342, to determine whether a relationship exists between failure of fertilization and sperm chromatin quality. Sperm chromatin packaging quality was assessed using the chromomydn A3 (CMA3) fluorochrome, and the presence of DNA damage in spermatozoa, using in-situ nick translation. Normal males present sperm parameters with a normal morphology of >20%, CMA3 fluorescence of <30% and exhibit endogenous nicks in <10% of their spermatozoa. When patients were separated according to these values no difference was observed in their fertilization rates after ICSL When the unfertilized ICSI oocytes were examined, we found that patients with CMA3 fluorescence of <30% and nicks in <10% of their spermatozoa had only 17.5 and 21.6% respectively of their unfertilized oocytes containing spermatozoa that remained condensed. In contrast, patients with higher CMA3 and nick values had a significantly higher number, 412 and 48.9%, of their unfertilized oocytes containing condensed spermatozoa. Sperm morphology did not show any such pattern. The percentage of spermatozoa which had initiated decondensation in unfertilized oocytes was not influenced by morphology, CMA3 fluorescence or nicks. In light of these results we postulate that poor chromatin packaging and/or damaged DNA may contribute to failure of sperm decondensation after ICSI and result in failure of fertilizatio
Case studies of automation in services
A full understanding of the technological complexity underlying robotics and automation is still lacking, most of all when focusing on the impacts on work in services. By means of a qualitative analysis based on over 50 interviews to HR managers, IT technicians, workers and trade union delegates, this work provides evidence on the main changes occurring at shopfloor level in selected Italian companies having adopted technological artefacts potentially affecting labour tasks by automating processes. The analysis of interviews complemented with visits to the companies and desk research on business documents highlights that so far labour displacement due to the adoption of automation technologies is not yet in place, while tasks and organizational reconfiguration appear more widespread. Major heterogeneity applies across plants due to the final product/service produced, the techno-organizational capabilities of the firm and the type of strategic orientation versus technological adoption. These elements also affect drivers and barriers to technological adoption. Overall, the analysis confirms the complexity in automating presumably low-value-added phases: human labour remains crucial in conducting activities that require flexibility, adaptability and reconfiguration of physical tasks. Further, human agency and worker representation, in particular the role of trade unions, are almost disregarded and not considered by the firms when deciding to introduce a new technology
Gene Modulation by Peptide Nucleic Acids (PNAs) Targeting microRNAs (miRs)
Since non-viral gene therapy was developed and employed in different in vitro and in vivo
experimental systems as an effective way to control and modify gene expression, RNA has
been considered as a molecular target of great relevance (Li &Huang, 2008, López-Fraga et
al., 2008). In combination with standard chemotherapy, the siRNA therapy can reduce the
chemoresistance of certain cancers, demonstrating its potential for treating many malignant
diseases. Examples of RNA sequences to be targeted for therapeutic applications are
mRNAs coding oncoproteins or RNA coding anti-apoptotic proteins for the development of
anti-cancer therapy.
In the last years, progresses in molecular biology have allowed to identify many genes
Coding for small non coding RNA molecules, microRNA (miRNAs or miRs), able to
regulate gene expression at the translation level (Huang et al., 2008, Shrivastava &
Shrivastava, 2008, Sahu et al. 2007, Orlacchio et al., 2007, Williams et al., 2008,
Papagiannakopoulos & Kosik, 2008). Accordingly, an increasing number of reports associate
the changed expression with specific phenotypes and even with pathological conditions
(Garzon & Croce, 2008, Mascellani et al., 2008, Sontheimer & Carthew, 2005, Filipowicz et
al., 2005, Alvarez-Garcia & Miska, 2005). Interestingly, microRNAs play a double role in
cancer, behaving both as oncogenes or tumor suppressor genes. In general, miRs promoting
cancer targets mRNA coding for tumor-suppression proteins, while microRNAs exhibiting
tumor-suppression properties usually target mRNAs coding oncoproteins. MicroRNAs
which have been demonstrated to play a crucial role in the initiation and progression of
human cancer are defined as oncogenic miRNAs (oncomiRs) (Cho, 2007). The oncomiR
expression profiling of human malignancies has also identified a number of diagnostic and
prognostic cancer signals (Cho, 2007, Lowery et al., 2008). Moreover, microRNAs have been
firmly demonstrated to be involved in cancer metastasis (metastamiRs).
Examples of metastasis-promoting microRNAs are, miR-10b (Calin et al., 2006), miR-373 and -
520c (Woods et al., 2007), miR-21, -143 and -182 (Hayashita et al., 2005; Si et al., 2007; Zhu et al.,2007). Reviews on metastamiR has been recently published Hurst et al. (Hurst et al. 2009,
Edmonds et al. 2009). Reviews on metastamiRs has been recently published by Hurst et al
A performance score of the quality of inpatient diabetes care is a marker of clinical outcomes and suggests a cause-effect relationship between hypoglycaemia and the risk of in-hospital mortality
Aims: To build a tool to assess the management of inpatients with diabetes mellitus and to investigate its relationship, if any, with clinical outcomes. Materials and methods: A total of 678 patients from different settings, Internal Medicine (IMU, n = 255), General Surgery (GSU, n = 230) and Intensive Care (ICU, n = 193) Units, were enrolled. A work-flow of clinical care of diabetes was created according to guidelines. The workflow was divided into five different domains: (a) initial assessment; (b) glucose monitoring; (c) medical therapy; (d) consultancies; (e) discharge. Each domain was assessed by a performance score (PS), computed as the sum of the scores achieved in a set of indicators of clinical appropriateness, management and patient empowerment. Appropriate glucose goals were included as intermediate phenotypes. Clinical outcomes included: hypoglycaemia, survival rate and clinical conditions at discharge. Results: The total PS and those of initial assessment and glucose monitoring were significantly lower in GSU with respect to IMU and ICU (P <.0001). The glucose monitoring PS was associated with lower risk of hypoglycaemia (OR = 0.55; P <.0001), whereas both the PSs of glucose monitoring and medical therapy resulted associated with higher in-hospital survival only in the IMU ward (OR = 6.67 P =.001 and OR = 2.38 P =.03, respectively). Instrumental variable analysis with the aid of PS of glucose monitoring showed that hypoglycaemia may play a causal role in in-hospital mortality (P =.04). Conclusions: The quality of in-hospital care of diabetes may affect patient outcomes, including glucose control and the risk of hypoglycaemia, and through the latter it may influence the risk of in-hospital mortality
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