Publications by authors named "Miriam Calabrese"

The -N(CH) residue is present in acetylcholine (ACh) and in many of its analogues which are used as selective ACh agonist or antagonists for human therapy. The X-ray structures of four ACh derivatives show the presence of short and linear contacts between the C atoms of -N(CH) groups and lone pair possessing atoms. These contacts can be rationalized as tetrel bonds (TtBs) thanks to their geometric features.

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Adducts between OsO and Lewis bases exert a role in important oxidation processes such as epoxidation and dihydroxylation. It has been shown that the attractive interaction driving the formation of these adducts is a σ-hole bond involving the metal as the electrophilic species; the term Osme Bond (OmB) was proposed for designating it. Here some new adducts between OsO and various bases have been characterized through single crystal x-ray diffraction (XRD) and computational studies (density functional theory, DFT), confirming the existence of a robust correlation between σ-hole interaction energy and deformation of the tetrahedral geometry of OsO.

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H-selenite anions (HSeO ) form in the solid unprecedented anionic supramolecular chains wherein single units are assembled via alternating short Se⋅⋅⋅O and H⋅⋅⋅O contacts. Crystallographic analyses and computational studies (the quantum theory of "atoms-in-molecules", QTAIM, and the noncovalent interaction plot, NCIPlot) consistently prove the attractive nature of these chalcogen bonds (ChBs) and hydrogen honds (HBs), the Janus-type character of HSeO anions which act as both donors and acceptors of ChB and HB, and the possible stability of anion dimers in solution. The effectiveness of the ChBs herein described may lead to consider the HSeO moiety as a new entry in the toolbox of crystal engineering based on ChB.

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Matere bonds (MaB) to rhenium in a set of organic perrhenates are probed Re solid-state NMR in applied magnetic fields of up to 35.2 T, and Re NQR. Re quadrupolar couplings distinguish between MaB samples and control samples, and their precise values are governed by shear strain of the ReO anions.

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Analyses of the Cambridge Structural Database and theoretical calculations (PBE0-D3/def2-TZVP level, atoms-in-molecules, natural bond orbital studies) prove the formation of net attractive noncovalent interactions between group 5 elements and electron-rich atoms (neutral or anionic). These kinds of bonding are markedly different from coordination bonds formed by the same elements and possess the distinctive features of σ-hole interactions. The term erythronium bond is proposed to denote these bonds.

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C(sp) atoms are known to act as electrophilic sites in self-assembly processes, and in all cases reported till now, they form only one interaction with nucleophiles; that is, they function as monodentate tetrel bond donors. This manuscript reports experimental (X-ray structural analysis) and theoretical evidence (DFT calculations), proving that the methylene carbon in bis-pyridinium methylene salts establishes two short and directional C(sp)···anion interactions; that is, they function as bidentate tetrel bond donors.

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Single crystal X-ray diffraction of iodate and bromate salts shows that the I and Br atoms in IO and BrO anions form short and linear O-I/Br⋅⋅⋅O contacts with the O atoms of nearby anions. Non-centrosymmetric systems are formed wherein anions are orderly aligned into supramolecular 1D and 2D networks. Theoretical evidences, namely the outcome of QTAIM and NCIplot studies, prove the attractive nature of these contacts and the ability of iodate and bromate anions to act as robust halogen bond (HaB) donors.

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In recent years Pd(II) and Pt(II) cases have been reported wherein metals in square planar complexes were used as nucleophilic partners to construct supramolecular assemblies with electrophilic molecules like σ-hole and π-hole donors. The formation of such assemblies is based on the nucleophilicity and accessibility of the d orbital (in group-10 elements) in the square-planar complexes. This opens new avenues in inorganic chemistry and crystal engineering as it enriches the current toolbox of noncovalent interactions and supramolecular synthons thus allowing the design of new types of architectures in the solid state.

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Methyltrioxorhenium(VII) (MTO) is a widely employed catalyst for metathesis, olefination, and most importantly, oxidation reactions. It is often preferred to other oxometal complexes due to its stability in air and higher efficiency. The seminal papers of K.

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Single crystal X-ray analyses show that iodine in pyridinium periodates acts as a halogen bond (HaB) donor forming short and almost linear contacts with neutral and anionic electron donors. A combination of QTAIM and NCIplot computational tools proves the attractive nature of these contacts.

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This communication reports experimental and theoretical evidences of σ-hole interactions in adducts between nitrogen or oxygen nucleophiles and tetroxides of osmium or other group 8 elements. Cocrystals between pyridine or pyridine N-oxide derivatives and osmium tetroxide are characterized through various techniques and rationalized as σ-hole interactions using DFT calculations and several other computational tools. We propose the term "osme bond" (OmB, Om=Fe, Ru, Os, (Hs)) for naming the noncovalent interactions wherein group 8 elements have the role of the electrophile.

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This longitudinal pilot study examined differences in demographic characteristics of 101 patients with advanced illness (cancer, AIDS) and 81 Family caregivers, evaluated the reliability of the Memorial Symptom Assessment Scale for these patients and their family caregivers; obtained preliminary data regarding similarities or differences in the symptom experience oF these patients and their family caregivers and changes in symptoms over time; and identified demographic variables that may be potential covariates related to the symptom experience. All demographic variables were significantly different for patients with advanced cancer and AIDS, and their symptom experience is similar only with regard to psychologic symptoms; however, based on the Memorial Symptom Assessment Scale, cancer and AIDS patients and their family caregivers have similar symptom experiences, indicating the need for palliative care for both patients and family. Further research is needed to establish the reliability of the Memorial Symptom Assessment Scale for use with family caregivers.

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Background: Although definitions of palliative care include quality of life as a central concern, little research has been published about both the quality of life of patients with advanced illness and their family members, and particularly the changes in their quality of life over time.

Objectives: The aims of this prospective longitudinal pilot study were to: (1) establish the reliability of multidimensional quality of life instruments based on patients with acquired immune deficiency syndrome (AIDS) and patients with cancer and caregivers; (2) identify differences in quality of life between patients with advanced AIDS and cancer, and their family caregivers with consideration of mortality, attrition, and compliance rates; and (3) examine differences in demographic variables and their potential confounding effect when measuring quality of life.

Methods: The sample included 101 patients with advanced illness (63 patients with advanced AIDS and 38 with advanced cancer) and 81 family caregivers (43 caregivers for patients with AIDS and 38 caregivers for patients with cancer).

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Based on a longitudinal, quality-of-life study, this article presents pilot data regarding the spiritual well-being of patients with advanced cancer or AIDS and their family caregivers. Data include similarities and differences between the patient and caregiver populations and patient/family caregiver dyads as well as trends with regard to changes in spiritual well-being during the illness and dying process. The reliability of the Spiritual Well-Being Scale was examined for patient and caregiver groups, as was the relationship between selected demographic variables and spiritual well-being.

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A longitudinal feasibility study regarding quality of life and interventions for patients with advanced cancer or AIDS and their family caregivers was conducted to determine issues related to their recruitment and retention and to obtain pilot data relevant to the development of a larger study. At the completion of the study, a focus group consisting of the members of the palliative care research team was convened to identify barriers to and facilitators of the research process based on their research experience. The purpose of this article is to (1) describe recruitment, mortality rates, attrition rates, and compliance with data collection of patients and family caregivers experiencing an advanced illness and to (2) examine the researchers' perspectives regarding barriers to and facilitators of the research process that relate to patients and family caregivers, institutions, the data collection process, and their personal experiences.

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