Endogenous and artificial miRNAs explore a rich variety of conformations: a potential relationship between secondary structure and biological functionality.

Mature microRNAs are short non-coding RNA sequences which upon incorporation into the RISC ribonucleoprotein complex, play a crucial role in regulation of gene expression. However, miRNAs can exist within the cell also as free molecules fulfilling their biological activity. Therefore, it is emerging that in addition to sequence even the structure adopted by mature miRNAs might play an important role to reach the target. Indeed, we analysed by several spectroscopic techniques the secondary structures of two artificial miRNAs selected by computational tool (miR-Synth) as best candidates to silence c-MET and EGFR genes and of two endogenous miRNAs (miR-15a and miR-15b) having the same seed region, but different biological activity. Our results demonstrate that both endogenous and artificial miRNAs can arrange in several 3D-structures which affect their activity and selectivity toward the targets.

O'nil Anteversa® mini-plate for stable hip fracture: first experience considerations and outcomes.

Hip fractures are associated with a 20% one-year mortality and a 50% loss of function. Over 700,000 deaths are estimated to occur annually worldwide following hip fractures. Concern exist regarding which is the best implant for extracapsular fractures fixation. For a correct positioning of the cephalic screw, a new plate (O'Nil Anteversa® mini-plate, Intrauma, Torino, Italy) with a fixed 8°of anteversion in the axial plane was developed. A total of 22 patients with an intertrochanteric fracture underwent surgery with Anteversa® mini-plate between October 2016 and April 2017. Data collected included patients' age at surgery, gender, fracture type, operative side, surgeon, type of implant, TAD, CalTAD and TADCalTAD. All patients underwent clinical and radiographic evaluations according to the AO Surgery Reference classification. The mean TAD, CalTAD and TADcalTAD for the entire population of study were, respectively, 20.18±7.5 mm, 20.45±7.25 mm, and 40.62±14.44 mm. The mean TAD, CalTAD and TADcalTAD of those patients who experienced mobilisation of the cephalic screw were, respectively, 20.26±5.87 mm, 19.53±5.47 mm, and 39.8±11.16 mm. Three patients experienced mobilisation of the cephalic screw, and none of these had a TAD greater than 25 mm, a CalTAD greater of 25mm or a TADcalTAD greater than 50 mm. This type of device meets the essential requirements for a correct treatment of intertrochanteric fractures in elderly patients. However, the excessive need of attention in each step, and the consequent increased time of surgery, could be seen as a limitation for its use.

Anti-HIV activity of new higher order G-quadruplex aptamers obtained from tetra-end-linked oligonucleotides.

By combining the ability of short G-rich oligodeoxyribonucleotides (ODNs) containing the sequence 5'CGGA3' to form higher order G-quadruplex (G4) complexes with the tetra-end-linked (TEL) concept to produce aptamers targeting the HIV envelope glycoprotein 120 (gp120), three new TEL-ODNs (1-3) having the sequence 5'CGGAGG3' were synthesized with the aim of studying the effect of G4 dimerization on their anti-HIV activity. Furthermore, in order to investigate the effect of the groups at the 5' position, the 5' ends of 1-3 were left uncapped (1) or capped with either the lipophilic dimethoxytrityl (DMT) (2) or the hydrophilic glucosyl-4-phosphate (3) moieties. The here reported results demonstrate that only the DMT-substituted TEL-ODN 2 is effective in protecting human MT-4 cell cultures from HIV infection (76% max protection), notwithstanding all the three new aptamers proved to be capable of forming stable higher order dimeric G4s when annealed in K+-containing buffer, thus suggesting that the recognition of a hydrophobic pocket on the target glycoprotein by the aptamers represents a main structural feature for triggering their anti-HIV activity.

Stabilization vs. destabilization of G-quadruplex superstructures: the role of the porphyrin derivative having spermine arms.

The interaction of the porphyrin derivative H2TCPPSpm4, having spermine pendants in the four meso positions, with the G-quadruplex (GQ) structure formed by the DNA aptamer TGGGAG has been investigated by means of UV, electronic circular dichroism and PAGE studies. The results reported here demonstrate that the porphyrin derivative is capable of stabilizing or destabilizing the higher-ordered structures of parallel GQs, depending on the method used to reach their relative stoichiometry (titration vs. single addition). Noteworthily, when two equivalents of H2TCPPSpm4 were mixed directly with one equivalent of the (TGGGAG)4 GQ to reach a 2 : 1 H2TCPPSpm4 : GQ ratio T1/2 higher than 80 °C was also observed confirming the presence of higher-ordered GQ structures.

miR302 regulates SNAI1 expression to control mesangial cell plasticity.

Cell fate decisions are controlled by the interplay of transcription factors and epigenetic modifiers, which together determine cellular identity. Here we elaborate on the role of miR302 in the regulation of cell plasticity. Overexpression of miR302 effected silencing of the TGFß type II receptor and facilitated plasticity in a manner distinct from pluripotency, characterized by increased expression of Snail. miR302 overexpressing mesangial cells also exhibited enhanced expression of EZH2 coincident with Snail upregulation. esiRNA silencing of each component suggest that Smad3 and EZH2 are part of a complex that regulates plasticity and that miR302 regulates EZH2 and Snail independently. Subsequent manipulation of miR302 overexpressing cells demonstrated the potential of using this approach for reprogramming as evidenced by de novo expression of the tight junction components ZO-1 and E-cadherin and the formation of ZO-1 containing tight junctions. Understanding the processes through which dynamic epigenetic silencing is controlled in adults cells will allow us to address the epigenetic state of acquired disease and whether original states, regenerative in nature, can be restored with therapy.

[Breast metastases from lung cancers with the EGFR mutation]. / Métastases mammaires des cancers bronchopulmonaires avec mutation de l'EGFR.

INTRODUCTION: The breast is a rare site for metastases from lung cancers. Their occurrence in patients with adenocarcinoma which has the EGFR mutation is exceptional. In this context, it is sometimes difficult to differentiate a second primary breast cancer from a breast metastasis. OBSERVATIONS: We report the cases of two patients who developed breast metastases from lung adenocarcinoma that was TTF1 positive with a deletion of exon 19 of the EGFR gene. A non-smoking woman of Asian origin, presented with a solitary breast metastasis 29 months after being established on first-line chemotherapy. The second case was a Caucasian patient who was an active smoker presented with tumor progression with multiple metastases including involvement of both breasts 10 months after the start of treatment with a tyrosine kinase inhibitor. In both, tumor cells from the breast showed positive immunostaining for TTF1 and genotyping detected the presence of the deletion of exon 19 of the EGFR gene. CONCLUSION: In patients with lung adenocarcinoma and EGFR mutation, immunohistochemical examination, including TTF1 and genotyping of synchronous breast tumour, is needed to confirm its metastatic nature and to guide treatment.

Management of malignant pleural mesothelioma: a French multicenter retrospective study (GFPC 0802 study).

BACKGROUND: Malignant pleural mesothelioma (MPM) is a rare disease with poor prognosis in spite of significant improvement in survival, due to new chemotherapy regimens. We describe here patients' profiles and management in daily practice in France. METHODS: Observational retrospective study. Data were collected from medical files. All patients with histologically proven MPM diagnosed from January 2005 to December 2008 were included in the participating sites. RESULTS: Four hundred and six patients were included in 37 sites: mean age 68.9 ± 9.8 years, male predominance (sex ratio 3.27), latency of the disease 45.7 years, epithelioïd type 83 %. Diagnosis was made using thoracoscopy in 80.8 % of patients. Radical surgery was performed in 6.2 % of cases. Chemotherapy was administered to 74.6 % of patients. First line regimens consisted mainly of platinum + pemetrexed (91 %) or pemetrexed alone (7 %). Objective response rate was 17.2 % and another 41.6 % of patients experienced disease stabilization. Half of these patients underwent second line chemotherapy (platinium + pemetrexed 31.6 %, pemetrexed alone 24.6 %), resulting in a 6 % response rate. Third-line chemotherapy (56 patients) yielded disease control in 5.4 % of cases. CONCLUSIONS: The management of MPM in France is usually in accordance with guidelines. Response rates are somewhat lower than those described in clinical trials.

Outstanding effects on antithrombin activity of modified TBA diastereomers containing an optically pure acyclic nucleotide analogue.

Herein, we report optically pure modified acyclic nucleosides as ideal probes for aptamer modification. These new monomers offer unique advantages in exploring the role played in thrombin inhibition by a single residue modification at key positions of the TBA structure.

Studies on the influence of inversion of polarity sites on the dG residues glycosidic conformation in quadruplex structures.

Insights into the influence of inversion of polarity sites on the dG residues glycosidic conformation in quadruplexes is presented. The NMR studies concern modified oligodeoxynucleotides based on the quadruplex forming sequence TGGGT.

A topological classification of G-quadruplex structures.

A topological classification of most quadruplex structures is proposed, based on two main characteristics: 1) the relative orientation of the strands and 2) the nature of the loops connecting the strands.

[Splenic metastasis from a bronchial carcinoma]. / Métastase splénique d'un cancer broncho-pulmonaire.

INTRODUCTION: Isolated splenic metastases from a bronchial carcinoma, without other visceral metastatic involvement, are exceptionally uncommon. CASE REPORT: The authors report the finding of an isolated splenic metastasis 21 months after a left pneumonectomy for an undifferentiated large cell carcinoma, initially staged pT3N1M0. The splenic metastasis presented as a major deterioration in general health and sharp pains in the left hypochondrium. Splenectomy confirmed the metastatic nature of the splenic tumour and relieved the severe abdominal pains. Two years after the splenectomy and with out adjuvant treatment the patient remains in complete remission. CONCLUSION: Splenectomy for a metastasis from a bronchial carcinoma should avoid the later complications of this type of metastasis: severe abdominal pain, splenic rupture and compression of neighbouring vessels. If the bronchial carcinoma is controlled locally and the splenic metastasis is isolated, splenectomy offers, perhaps, a further chance of prolonged survival.

[Choroidal metastases in lung cancer]. / Métastases choroïdiennes des cancers broncho-pulmonaires.

INTRODUCTION: Ocular metastases are rare and their diagnosis can be difficult, being dependent on a combination of clinical examination of the eye, ultrasound, angiography and magnetic resonance imaging. CLINICAL CASE: We describe two cases of cases of choroidal metastases in patients with a bronchogenic carcinoma. In both cases the metastases presented at a late stage in the disease and occurred in association with cerebral metastases. One patient had an epidermoid tumour the other a small cell carcinoma. Loss of visual acuity, which was slowly progressive in the first case and abrupt in the second, led to the diagnosis of choroidal metastases. Following radiotherapy in a dose of 30 Gray delivered to the posterior segment of the eye, both patients' visual acuity recovered to near normal within a few weeks. CONCLUSION: If patients with lung cancer develop visual disturbance the possibility of choroidal metastases should be considered. Ocular radiotherapy can often ameliorate disabling visual disturbance, significantly improving quality of life.

Synthesis of 5-methylamino-2'-deoxyuridine derivatives.

Reductive amination of 3',5'-O-(tetraisopropyldisilyloxane-1,3-diyl)-2'-deoxy-5-formyluridine with several aliphatic and aromatic amines, in various solvents, is described. In the case of aliphatic amines, the expected C-5 substituted methylamino pyrimidine nucleosides are formed along with by-products deriving from opening of the pyrimidine ring. Relative amounts of the by-products depend upon the polarity of the solvent employed.

Solid-phase synthesis of oligonucleotides containing a bipyridine ligand at the 3'-3' inversion of polarity site.

The preparation of a solid support useful for the synthesis of oligonucleotides with a 3'-3' inversion of polarity, via a linker containing a chelating molecule, namely 2,2'-bipyridine, is described.

Use of automated solid-phase extraction equipment for the determination of isoniazid in milk.

The possibility of using automated equipment for solid phase extraction of isoniazid from milk has been investigated. This equipment provides two noteworthy advantages: it shortens the time of analysis and avoids SPE column plugging, stabilizing flow rates. After setting the correct programme on software controlling the equipment, some validation parameters have been determined to obtain recovery and repeatability data. The mean recovery for spiked samples resulted in the range 75-95%, the standard error ranged from -5 to -20% while the RSD varied from 2 to 22%. Therefore the method can be considered reliable and fast.

[Pulmonary lymphangioleiomyomatosis in a menopaused woman]. / Lymphangioléiomyomatose pulmonaire chez une femme ménopausée.

We report an unusual case of pulmonary lymphangioleiomyomatosis in a menopaused woman who had been taking estrogen hormone replacement therapy for several years. The characteristic feature of this uncommon disease is a proliferation of non-tumoral abnormal smooth muscle cells within the alveolar walls, and around the bronchi, lymph nodes and blood vessels. About twenty cases of pulmonary lymphangioleiomyomatosis have been described in menopaused women, who generally were taking estrogen hormone replacement therapy. This subpopulation does not appear to present any particular clinical, functional or radiographic features.

Clenbuterol residues in non-liver containing meat as a cause of collective food poisoning.

beta 2-adrenergic agonists, particularly clenbuterol, are illegally used as growth promoters to obtain lean in meat. Their administration in feedlots can constitute a severe risk for animal welfare and exposes consumers to involuntary drug consumption at pharmacological active concentrations. Reported poisoning episodes have been associated with the consumption of beef liver where clenbuterol residues concentrate. In August 1996, 62 persons asked for medical help at the emergency rooms of 2 hospitals near the city of Caserta (Italy). Their clinical profile was characteristic of previously occurring clenbuterol intoxication, which reported superventricular extrasystoles and atrial fibrillation. All patients had non-liver beef meat consumption 10-30 min to 2-3 h before symptoms developed. An ELISA screening test specific for clenbuterol confirmed the drug's presence. Definitive confirmation of clenbuterol and determination of the drug content in meat samples were obtained by GC-MS, using 2 different derivatization. Concentrations in the meats ranged from 0.8 to 7.4 mg/kg. These analytical data provided evidence of the seriousness of the poisoning and helped the National Health System identify other possible misinterpreted cases. This case demonstrates that clenbuterol poisoning can also occur after consumption of beef meat other than liver.

Use of automated solid-phase extraction equipment for the determination of ivermectin residues in animal liver by HPLC.

An improvement of the method commonly used for the determination of ivermectin is proposed. An automatic system is used for the solid-phase extraction column purification stage in order to provide more efficient and fast sample preparation, prior to separation and quantification by HPLC. Some tests were performed to obtain recovery and repeatability data. The mean recovery for spiked samples (five replicates twice at three concentration levels) was more than 90% in the concentration range 7.5-30 ng g-1. The tests for accuracy (five replicates at three concentration levels) gave a standard error of -2.0% at the highest and -19.2% at the lowest concentration. Concerning repeatability data (five replicates twice at three concentration levels), in the concentration range 7.5-30 ng g-1 the RSD varied from 9.29 to 2.15%. The described method was used in a survey on the presence of ivermectin in food-producing animals in two regions of southern Italy; no positives out of 250 liver samples were found.