54 research outputs found

    Chirality Transfer in a Calixarene-Based Directional Pseudorotaxane Complex

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    Hexamethoxycalix[6]arene 3 forms a directional pseudorotaxane complex with the chiral axle (S)-(alpha-methyl-benzyl)benzylammonium 2(+). Between the two (endo-chiral)-2(+)@3 and (exo-chiral)-2(+)@3 pseudorotaxane stereoisomers, the former is preferentially formed. This result confirms the validity of the "endo-alpha-methyl-benzyl rule", previously reported by us. DFT calculations suggest that C-H horizontal ellipsis pi interactions between the methyl group of 2(+) and the calixarene aromatic rings, determine the stereoselectivity of the threading process toward the "endo-alpha-methyl-benzyl preference". An amplification of optical rotation is observed upon formation of the pseudorotaxane complex (endo-chiral)-2(+)@3 with respect to free axle 2(+). Thus, the specifical rotation of the 1:1 mixture of chiral 2(+)center dot B(ArF)(4)(-) salt and achiral 3 was augmented upon formation of the pseudorotaxane and DFT calculations were used to rationalize this result

    Ring size effect on the solid state assembly of propargyl substituted hexa- and octacyclic peptoids

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    The investigation of the solid state assembly of propargyl substituted hexa- and octacyclic peptoids highlights the effect of ring size in determining the packing arrangement of the macrocycles. A layered arrangement is obtained in the case of the hexacyclic peptoid 1 and a tubular arrangement in the case of the octacyclic peptoid 2. Guest molecules either intercalate between the layers as in 1 or are located within the peptoid nanotube as in 2

    Geographical heterogeneity of clinical and serological phenotypes of systemic sclerosis observed at tertiary referral centres. The experience of the Italian SIR-SPRING registry and review of the world literature

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    Introduction: Systemic sclerosis (SSc) is characterized by a complex etiopathogenesis encompassing both host genetic and environmental -infectious/toxic- factors responsible for altered fibrogenesis and diffuse microangiopathy. A wide spectrum of clinical phenotypes may be observed in patients' populations from different geographical areas. We investigated the prevalence of specific clinical and serological phenotypes in patients with definite SSc enrolled at tertiary referral centres in different Italian geographical macro-areas. The observed findings were compared with those reported in the world literature.Materials and methods: The clinical features of 1538 patients (161 M, 10.5%; mean age 59.8 +/- 26.9 yrs.; mean disease duration 8.9 +/- 7.7 yrs) with definite SSc recruited in 38 tertiary referral centres of the SPRING (Systemic sclerosis Progression INvestiGation Group) registry promoted by Italian Society of Rheumatology (SIR) were obtained and clustered according to Italian geographical macroareas.Results: Patients living in Southern Italy were characterized by more severe clinical and/or serological SSc phenotypes compared to those in Northern and Central Italy; namely, they show increased percentages of diffuse cutaneous SSc, digital ulcers, sicca syndrome, muscle involvement, arthritis, cardiopulmonary symptoms, interstitial lung involvement at HRCT, as well increased prevalence of serum anti-Scl70 autoantibodies. In the same SSc population immunusppressive drugs were frequently employed. The review of the literature underlined the geographical heterogeneity of SSc phenotypes, even if the observed findings are scarcely comparable due to the variability of methodological approaches.Conclusion: The phenotypical differences among SSc patients' subgroups from Italian macro-areas might be correlated to genetic/environmental co-factors, and possibly to a not equally distributed national network of information and healthcare facilities

    Influence of Antisynthetase Antibodies Specificities on Antisynthetase Syndrome Clinical Spectrum TimeCourse

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    Introduction: Increased cardiovascular (CV) morbidity and mortality is observed in inflammatory joint diseases (IJDs) such as rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis. However, the management of CV disease in these conditions is far from being well established.Areas covered: This review summarizes the main epidemiologic, pathophysiological, and clinical risk factors of CV disease associated with IJDs. Less common aspects on early diagnosis and risk stratification of the CV disease in these conditions are also discussed. In Europe, the most commonly used risk algorithm in patients with IJDs is the modified SCORE index based on the revised recommendations proposed by the EULAR task force in 2017.Expert opinion: Early identification of IJD patients at high risk of CV disease is essential. It should include the use of complementary noninvasive imaging techniques. A multidisciplinary approach aimed to improve heart-healthy habits, including strict control of classic CV risk factors is crucial. Adequate management of the underlying IJD is also of main importance since the reduction of disease activity decreases the risk of CV events. Non-steroidal anti-inflammatory drugs may have a lesser harmful effect in IJD than in the general population, due to their anti-inflammatory effects along with other potential beneficial effects.This research was partially funded by FOREUM—Foundation for Research in Rheumatolog

    How ring size and side chains affect the solid state assembly of cyclopeptoids

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    Contiene: - Convenio Marco de Pasantías entre la Universidad Nacional de La Plata y Danone Argentina S.A. Pasantías de Alumnos - Convenio Marco de Pasantías entre la UNLP y Alaro S.A. - Convenio Marco de Pasantías entre la UNLP y Furukawa Electric Latam S.A. - Convenio Marco de Pasantías entre la UNLP y Ligantex S.A. - Convenio Marco de Pasantías sucripto entre Celerative SRL y la UNLP - Convenio Marco de Pasantías sucripto entre Miller Building International S.A. y la UNLP - Ordenanza N° 296. Consejo Superior - Ordenanza N° 297. Consejo Superior - Resolución N° 4 y Texto Ordenado de la Ordenanza N° 181. Consejo Superior - Resolución N° 258. Facultad de Periodismo y Comunicación Social - Resolución N° 638. Facultad de Informática - Resolución N° 1249. Presidencia - Resolución N° 1251. Presidencia - Resolución N° 1926. Facultad de Ciencias ExactasUniversidad Nacional de La Plat
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