104 research outputs found

    Differential reactivity of the inner and outer positions of Au25(SCH2CH2Ph)18 dimeric staples under place exchange conditions

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    The kinetic anal. of the place exchange reaction on the neutral Au25(SCH2CH2Ph)\u200b18 cluster by using 4-\u200bfluorobenzylthiol and a series of substituted arylthiols allowed us to establish, for the first time, that the selectivity for the inner and outer positions of the dimeric staples of the cluster can be modulated by using incoming thiols with different structures

    Thermodynamic and Kinetic Stabilities of Al(III) Complexes with N2O3 Pentadentate Ligands

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    : Al(III) complexes have been recently investigated for their potential use in imaging with positron emission tomography (PET) by formation of ternary complexes with the radioisotope fluorine-18 (18F). Although the derivatives of 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) are the most applied chelators for [Al18F]2+ labelling and (pre)clinical PET imaging, non-macrocyclic, semi-rigid pentadentate chelators having two N- and three O-donor atoms such as RESCA1 and AMPDA-HB have been proposed with the aim to allow room temperature labelling of temperature-sensitive biomolecules. The paucity of stability data on Al(III) complexes used for PET imaging instigated a complete thermodynamic and kinetic solution study on Al(III) complexes with aminomethylpiperidine (AMP) derivatives AMPTA and AMPDA-HB and the comparison with a RESCA1-like chelator CD3A-Bn (trans-1,2-diaminocyclohexane-N-benzyl-N,N',N'-triacetic acid). The stability constant of [Al(AMPDA-HB)] is about four orders of magnitude higher than that of [Al(AMPTA)] and [Al(CD3A-Bn)], highlighting the greater affinity of phenolates with respect to acetate O-donors. On the other hand, the kinetic inertness of the complexes, determined by following the Cu2+-mediated transmetallation reactions in the 7.5-10.5 pH range, resulted in a spontaneous and hydroxide-assisted dissociation slightly faster for [Al(AMPTA)] than for the other two complexes (t1/2 = 4.5 h for [Al(AMPTA)], 12.4 h for [Al(AMPDA-HB)], and 24.1 h for [Al(CD3A-Bn)] at pH 7.4 and 25 °C). Finally, the [AlF]2+ ternary complexes were prepared and their stability in reconstituted human serum was determined by 19F NMR experiments

    AAZTA-Like Ligands Bearing Phenolate Arms as Efficient Chelators for 68Ga Labelling in vitro and in vivo

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    : The introduction of a phenolate pendant arm in place of an acetate on AAZTA- and DATA-like ligands resulted in hepta- and hexadentate chelators able to form Ga(III) complexes with thermodynamic stability and kinetic inertness higher than that of other Ga(III) complexes based on the parent 6-amino-6-methylperhydro-1,4-diazepine scaffold. In particular, the heptadentate AAZ3A-endoHB with a phenolate arm on an endocyclic N-atom shows a logKGaL of 27.35 and a remarkable resistance to hydroxide coordination up to basic pH (pH>9). This behaviour allows to also improve the kinetic inertness of the complex showing a dissociation half-life (t1/2 ) at pH 7.4 of 76 h. Although also the hexadentate AAZ2A-exoHB chelator forms a stable (logKGaL =24.69) and inert (t1/2 =33 h at pH 7.4) Ga(III) complex, the 68 Ga labelling showed a better radiochemical yield with AAZ3A-endoHB, especially at room temperature. Thus, a bifunctional chelator of AAZ3A-endoHB was synthesized bearing an isothiocyanate group that was conjugated to the N-terminus of a c(RGD) peptide for integrin receptor targeting. Finally, the conjugate was successfully labelled with 68 Ga isotope, and the resulting radiotracer tested for its stability in human serum and then in vivo for targeting B16-F10 tumours with miniPET imaging

    A self-reported screening tool for detecting community-dwelling older persons with frailty syndrome in the absence of mobility disability : the FiND questionnaire

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    BACKGROUND: The "frailty syndrome" (a geriatric multidimensional condition characterized by decreased reserve and diminished resistance to stressors) represents a promising target of preventive interventions against disability in elders. Available screening tools for the identification of frailty in the absence of disability present major limitations. In particular, they have to be administered by a trained assessor, require special equipment, and/or do not discriminate between frail and disabled individuals. Aim of this study is to verify the agreement of a novel self-reported questionnaire (the "Frail Non-Disabled" [FiND] instrument) designed for detecting non-mobility disabled frail older persons with results from reference tools. METHODOLOGY/PRINCIPAL FINDINGS: Data are from 45 community-dwelling individuals aged 6560 years. Participants were asked to complete the FiND questionnaire separately exploring the frailty and disability domains. Then, a blinded assessor objectively measured the frailty status (using the phenotype proposed by Fried and colleagues) and mobility disability (using the 400-meter walk test). Cohen's kappa coefficients were calculated to determine the agreement between the FiND questionnaire with the reference instruments. Mean age of participants (women 62.2%) was 72.5 (standard deviation 8.2) years. Seven (15.6%) participants presented mobility disability as being unable to complete the 400-meter walk test. According to the frailty phenotype criteria, 25 (55.6%) participants were pre-frail or frail, and 13 (28.9%) were robust. Overall, a substantial agreement of the instrument with the reference tools (kappa\u200a=\u200a0.748, quadratic weighted kappa\u200a=\u200a0.836, both p values<0.001) was reported with only 7 (15.6%) participants incorrectly categorized. The agreement between results of the FiND disability domain and the 400-meter walk test was excellent (kappa\u200a=\u200a0.920, p<0.001). CONCLUSIONS/SIGNIFICANCE: The FiND questionnaire presents a very good capacity to correctly identify frail older persons without mobility disability living in the community. This screening tool may represent an opportunity for diffusing awareness about frailty and disability and supporting specific preventive campaigns

    Main clinical features in patients at their first psychiatric admission to Italian acute hospital psychiatric wards. The PERSEO study

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    BACKGROUND: Few data are available on subjects presenting to acute wards for the first time with psychotic symptoms. The aims of this paper are (i) to describe the epidemiological and clinical characteristics of patients at their first psychiatric admission (FPA), including socio-demographic features, risk factors, life habits, modalities of onset, psychiatric diagnoses and treatments before admission; (ii) to assess the aggressive behavior and the clinical management of FPA patients in Italian acute hospital psychiatric wards, called SPDCs (Servizio Psichiatrico Diagnosi e Cura = psychiatric service for diagnosis and management). METHOD: Cross-sectional observational multi-center study involving 62 Italian SPDCs (PERSEO – Psychiatric EmeRgency Study and EpidemiOlogy). RESULTS: 253 FPA aged <= 40 were identified among 2521 patients admitted to Italian SPDCs over the 5-month study period. About half of FPA patients showed an aggressive behavior as defined by a Modified Overt Aggression Scale (MOAS) score greater than 0 Vs 46% of non-FPA patients (p = 0.3651). The most common was verbal aggression, while about 20% of FPA patients actually engaged in physical aggression against other people. 74% of FPA patients had no diagnosis at admission, while 40% had received a previous psychopharmacological treatment, mainly benzodiazepines and antidepressants. During SPDC stay, diagnosis was established in 96% of FPA patients and a pharmacological therapy was prescribed to 95% of them, mainly benzodiazepines, antipsychotics and mood stabilizers. CONCLUSION: Subjects presenting at their first psychiatric ward admission have often not undergone previous adequate psychiatric assessment and diagnostic procedures. The first hospital admission allows diagnosis and psychopharmacological treatment to be established. In our population, aggressive behaviors were rather frequent, although most commonly verbal. Psychiatric symptoms, as evaluated by psychiatrists and patients, improved significantly from admission to discharge both for FPA and non-FPA patients

    Clinical features and therapeutic management of patients admitted to Italian acute hospital psychiatric units: the PERSEO (psychiatric emergency study and epidemiology) survey

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    <p>Abstract</p> <p>Background</p> <p>The PERSEO study (psychiatric emergency study and epidemiology) is a naturalistic, observational clinical survey in Italian acute hospital psychiatric units, called SPDCs (Servizio Psichiatrico Diagnosi e Cura; in English, the psychiatric service for diagnosis and management). The aims of this paper are: (i) to describe the epidemiological and clinical characteristics of patients, including sociodemographic features, risk factors, life habits and psychiatric diagnoses; and (ii) to assess the clinical management, subjective wellbeing and attitudes toward medications.</p> <p>Methods</p> <p>A total of 62 SPDCs distributed throughout Italy participated in the study and 2521 patients were enrolled over the 5-month study period.</p> <p>Results</p> <p>Almost half of patients (46%) showed an aggressive behaviour at admission to ward, but they engaged more commonly in verbal aggression (38%), than in aggression toward other people (20%). A total of 78% of patients had a psychiatric diagnosis at admission, most frequently schizophrenia (36%), followed by depression (16%) and personality disorders (14%), and no relevant changes in the diagnoses pattern were observed during hospital stay. Benzodiazepines were the most commonly prescribed drugs, regardless of diagnosis, at all time points. Overall, up to 83% of patients were treated with neuroleptic drugs and up to 27% received more than one neuroleptic either during hospital stay or at discharge. Atypical and conventional antipsychotics were equally prescribed for schizophrenia (59 vs 65% during stay and 59 vs 60% at discharge), while atypical drugs were preferred in schizoaffective psychoses (72 vs 49% during stay and 70 vs 46% at discharge) and depression (41 vs 32% during stay and 44 vs 25% at discharge). Atypical neuroleptics were slightly preferred to conventional ones at hospital discharge (52 vs 44%). Polypharmacy was in general widely used. Patient attitudes toward medications were on average positive and self-reported compliance increased during hospital stay.</p> <p>Conclusion</p> <p>Results confirm the widespread use of antipsychotics and the increasing trend in atypical drugs prescription, in both psychiatric in- and outpatients.</p

    Two randomised and placebo-controlled studies of an oral prostacyclin analogue (Iloprost) in severe leg ischaemia [The Oral Iloprost in severe Leg Ischaemia Study Group]

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    Two separate studies are described using the same prostacyclin analogue in a similar group of patients. Objectives: to assess the tolerability and efficacy of two dose regimens of oral Iloprost compared with placebo in the treatment of patients with ischaemic ulcers, gangrene or rest pain due to severe arterial disease over a period of 4 weeks (Study A) and one year (Study B). Design: multicentre, placebo controlled, double-blind, randomized prospective studies. Subjects & Methods: 178 (study A) and 624 (study B) patients with trophic skin lesions (ulcers or gangrene) or ischaemic rest pain due to severe arterial disease. To confirm severe arterial disease patients were required to have a systolic ankle Doppler pressure of 70 mmHg or less or a toe systolic Doppler pressure of 50 mmHg or less in one leg.In both studies patients were randomly allocated to three treatment groups: placebo, low dose Iloprost (50\u2013100 g twice a day) or high dose (150\u2013200 g twice a day) In Study A the main outcome measures were tolerability of different doses of Iloprost and death, major amputation, healing of trophic lesions and relief of rest pain at the end of the follow up, which was 5 months after the end of the treatment. In Study B the primary end point was time to major amputation and stroke or death up to 12 months. Secondary pre-defined end points included the combined end point of patients alive without amputation, no trophic skin changes, no rest pain and not on regular analgesics. Results: the proportion of patients who completed the 4-week treatment period in Study A at the intended dose was 58%, 43%, 45% respectively in the placebo, low dose and high dose Iloprost groups. In an intention to treat analysis the proportion of patients who survived without major amputation, ulcers or gangrene and had no rest pain was 11% in the placebo group, 19% in the low dose iloprost group and 28% in the high dose Iloprost group. The pooled Iloprost groups showed a statistically significantly better result than the placebo group (p=0.04), as did the high dose Iloprost group compared to the placebo (p=0.014). In Study B there was no treatment benefit in terms of a primary end point of amputation and death. However the secondary combined end point of patients who survived without a major amputation, ulcers or gangrene and had no rest pain, nor a need for regular analgesia was favourable for Iloprost, with 18% of patients in the placebo group reaching this optimal secondary end point, compared to 23% in the low dose Iloprost group and 26% in the higher dose Iloprost group (p<0.05). Conclusions: oral Iloprost administered for a year showed no clear benefit in patients with advanced severe leg ischaemia (PAOD III and IV). The results obtained with 4 weeks\u2019 treatment in Study A and in previous trials of intravenous Iloprost could not be reproduce

    Straightforward synthesis of fluorinated amphiphilic thiols

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    C8-perfluoroalkyl thiols bearing a polyoxyethylene chain of variable length were prepared in good yields following a straightforward synthetic strategy. These thiols are soluble in organic solvents of different polarities from chloroform to methanol. The thiol with a PEG550 chain shows very good solubility in water
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