The propensity for covalent organic frameworks to template polymer entanglement

The introduction of molecularly woven three-dimensional (3D) covalent organic framework (COF) crystals into polymers of varying types invokes different forms of contact between filler and polymer. Whereas the combination of woven COFs with amorphous and brittle polymethyl methacrylate results in surface interactions, the use of the liquid-crystalline polymer polyimide induces the formation of polymer-COF junctions. These junctions are generated by the threading of polymer chains through the pores of the nanocrystals, thus allowing for spatial arrangement of polymer strands. This offers a programmable pathway for unthreading polymer strands under stress and leads to the in situ formation of high-aspect-ratio nanofibrils, which dissipate energy during the fracture. Polymer-COF junctions also strengthen the filler-matrix interfaces and lower the percolation thresholds of the composites, enhancing strength, ductility, and toughness of the composites by adding small amounts (~1 weight %) of woven COF nanocrystals. The ability of the polymer strands to closely interact with the woven framework is highlighted as the main parameter to forming these junctions, thus affecting polymer chain penetration and conformation.

Hydrazine-Hydrazide-Linked Covalent Organic Frameworks for Water Harvesting

We report a postsynthetic strategy and its implementation to make covalent organic frameworks (COFs) with irreversible hydrazide linkages. This involved the synthesis of three 2D and 3D hydrazine-linked frameworks and their partial oxidation. The linkage synthesis and functional group transformation-hydrazine and hydrazide-were evidenced by ¹⁵N multi-CP-MAS NMR. In addition, the isothermal water uptake profiles of these frameworks were studied, leading to the discovery of one hydrazine-hydrazide-linked COF suitable for water harvesting from air in arid conditions. This COF displayed characteristic S-shaped water sorption profiles, a steep pore-filling step below 18% relative humidity at 25 °C, and a total uptake capacity of 0.45 g g^-1. We found that even small changes made on the molecular level can lead to major differences in the water isotherm profiles, therefore pointing to the utility of water sorption analysis as a complementary analytical tool to study linkage transformations.

[DOES A PRISONER HAVE THE RIGHT TO AUTONOMY? A CASE REPORT]

The case presented discusses a prisoner, Y, in his mid-sixties with longstanding medical conditions, who was sentenced to prolonged incarceration. Y refused conventional medicine because he believed that his medical condition was exacerbated by this treatment and only complementary alternative medicine (CAM) would be helpful. He therefore demanded to be treated only by CAM. He was ready to pay for the treatment out of his own pocket. In the prison where Y was previously incarcerated over the course of 12 years, he had access to CAM remedies which were purchased by his family. After being transferred to the current facility, Y was denied access to these remedies by the prison physicians. He appealed in court against this decision and was supported by a CAM specialist, who ascertained that the remedies under consideration were not hazardous to Y's health. This case report discusses the ethical aspects of a prisoner's autonomy to choose medical treatment even when his/her autonomy has been severely curtailed by virtue of the incarceration.

3D Covalent Organic Frameworks Selectively Crystallized through Conformational Design

We present a strategy whereby selective formation of imine covalent organic frameworks (COFs) based on linking of triangles and squares into the fjh topology was achieved by the conformational design of the building units. 1,3,5-Trimethyl-2,4,6-tris(4-formylphenyl)benzene (TTFB, triangle) and 1,1,2,2-tetrakis(4-aminophenyl)ethene (ETTA, square) were reticulated into [(TTFB)4(ETTA)3]imine, termed COF-790, which was fully characterized by spectroscopic, microscopic, and X-ray diffraction techniques. COF-790 exhibits permanent porosity and a Brunauer-Emmett-Teller (BET) surface area of 2650 m2 g-1. Key to the formation of this COF in crystalline form is the pre-designed conformation of the triangle and the square units to give dihedral angles in the range of 75-90°, without which the reaction results in the formation of amorphous product. We demonstrate the versatility of our strategy by also reporting the synthesis and characterization of two isoreticular forms of COF-790, COF-791 and COF-792, based on other square building units.

Standard Practices of Reticular Chemistry

Reticular chemistry is a growing field of science with a multitude of practitioners with diverse frames of thinking, making the need for standard practices and quality indicators ever more compelling.

Molecular Recognition and Cocrystallization of Methylated and Halogenated Fragments of Danicalipin A by Enantiopure Alleno-Acetylenic Cage Receptors

Enantiopure (P)₄- and (M)₄-configured alleno-acetylenic cage (AAC) receptors offer a highly defined interior for the complexation and structure elucidation of small molecule fragments of the stereochemically complex chlorosulfolipid danicalipin A. Solution (NMR), solid state (X-ray), and theoretical investigations of the formed host-guest complexes provide insight into the conformational preferences of 14 achiral and chiral derivatives of the danicalipin A chlorohydrin core in a confined, mostly hydrophobic environment, extending previously reported studies in polar solvents. The conserved binding mode of the guests permits deciphering the effect of functional group replacements on Gibbs binding energies ΔG. A strong contribution of conformational energies toward the binding affinities is revealed, which explains why the denser packing of larger apolar domains of the guests does not necessarily lead to higher association. Enantioselective binding of chiral guests, with energetic differences ΔΔG_293 K up to 0.7 kcal mol^-1 between diastereoisomeric complexes, is explained by hydrogen- and halogen-bonding, as well as dispersion interactions. Calorimetric studies (ITC) show that the stronger binding of one enantiomer is accompanied by an increased gain in enthalpy ΔH but at the cost of a larger entropic penalty TΔS stemming from tighter binding.

Case-Control Retrospective Study of Child Sexual Abuse History among Psychiatric Consultations in a General Hospital Emergency Room

BACKGROUND

A history of childhood sexual abuse (CSA) has been linked to a variety of physical and psychiatric illnesses, including ischemic heart disease and post-traumatic stress disorder (PTSD).

OBJECTIVES

To determine the prevalence of past CSA and re-traumatization among hospital psychiatric consultations and to determine whether a CSA group in a hospital setting shared characteristics with community samples described in the literature.

METHODS

We divided 228 consecutive psychiatric consultations into two groups. One group comprised patients with a past history of CSA while the other group had no such history. Both groups were further divided into a subgroup that presented with features of re-traumatization.

RESULTS

In the cohort, 38% described a history of CSA. Twenty patients were identified as presenting with features of re-traumatization. There were significant differences between the two groups. The patients with a history of CSA were more likely to have arrived at the emergency department (ED) during the preceding 12 months with a diagnosis of PTSD, personality disorder, and substance use disorder. There was a greater proportion of patients in the CSA group who had grown up in an ultra-Orthodox Jewish household and who currently identified as being secular.

CONCLUSIONS

The characteristics of the patients with past CSA in this study are similar to community-based samples, except for a significant gender difference. To the best of our knowledge, this study is the first to investigate CSA history during hospital ED psychiatric consultations. A history of CSA should be considered during psychiatric consultations in a general hospital ED admission.

Psychopathology of Israeli Soldiers Presenting to a General Hospital Emergency Department: Lessons for the Attending Physician and Psychiatrist

BACKGROUND

There is scant research on the psychopathology of Israeli soldiers who present to a general hospital emergency department (ED).

OBJECTIVES

To assess the psychopathology among a cohort of Israeli soldiers who presented to a general hospital ED for mental health assessment.

METHODS

The demographic and clinical characteristics of 124 consecutive soldiers who presented to the ED for psychiatric assessment between January 2008 and September 2012 were reviewed. Twenty-seven soldiers from the cohort were contacted for follow-up by telephone on average 52 months later.

RESULTS

The reasons for presentation to the ED, usually during the early stages of military service, included self-harming behavior, suicidal ideation, somatoform complaints, and dissatisfaction with their military service. Psychiatric diagnoses included adjustment disorder and personality disorder. Self-harming behavior/suicidal ideation was significantly correlated with unspecified adjustment disorder (P = 0.02) and personality disorder (P = 0.001). At follow-up, there was a lack of substantial psychopathology: none of the subjects engaged in self-harming behavior/suicidal ideation and a consistent trend was observed toward clinical improvement.

CONCLUSIONS

Psychiatric intervention of soldiers who present to a general hospital ED because of emotional difficulties may provide the opportunity for crisis intervention and validation of the soldier's distress. To the best of our knowledge this is the first Israeli study of psychopathology among soldiers who presented to an ED.

Alcohol Related Harm: Knowledge Assessment of Medical and Nursing Staff in a General Hospital

BACKGROUND

The prevalence of alcohol related harm (ARH) in Israel has traditionally been low. The lack of familiarity with ARH may derive from the fact that in the past there was limited clinical exposure to these harms. However, ARH is becoming more common in Israel but it is unclear whether the medical and nursing workforce's knowledge is adequate to manage these problems. Our main objective was to assess knowledge regarding ARH among medical and nursing staff (MNS) in an Israeli university affiliated general hospital. We also aimed to compare knowledge of different MNS groups Methods: One hundred and twenty-seven MNS including consultants (senior physicians), residents, interns and nursing staff completed the Knowledge of Psychiatric Aspects of Alcohol Questionnaire (KPAAQ), a validated measure of knowledge concerning ARH comprised of five categories.

RESULTS

There was no significant difference between the four MNS groups in overall mean KPAAQ scores that varied from 45% (nurses) to 54% (interns). However, direct comparisons indicate that physicians scored higher than nurses (p=0.02). overall. The mean score for the KPAAQ category "alcohol withdrawal syndrome" was below 40% for all MNS groups. Physicians scored significantly higher than nursing staff (p=0.005). All MNS mean scores were greater than 63% for the category "alcohol in pregnancy." This was the highest category score.

CONCLUSIONS

Assessment of knowledge regarding ARH among MNS in a general hospital with a standardized instrument demonstrated no significant difference in knowledge of ARH among nursing staff, interns, residents and consultants apart from knowledge about alcohol withdrawal. However, the overall score of the physicians as a whole was significantly higher than the nursing group. These findings suggest a need to implement educational interventions in MNS to increase knowledge of ARH so as to promote the provision of brief interventions for patients with ARH.

Preliminary results of a controlled educational intervention on alcohol related harm among medical students with a 12-month follow-up

BACKGROUND

There are no studies that use validated questionnaires on Alcohol Related Harm (ARH) in order to assess retention of educational programs among medical students. Objective of study to assess retention of an educational inter-vention on ARH among medical students.

METHOD

Seventeen fifth year medical students were assessed with the Knowledge of Psychiatric Aspects of Alcohol Questionnaire (KPAAQ) 12 months after an educational intervention on ARH and compared with a control group.

RESULTS

Significant retention was found in the study group.

CONCLUSIONS

This preliminary research is the first controlled study on medical student retention of an ARH educational intervention using a validated questionnaire.

[Analysis of therapy-relevant receptors in bone marrow carcinosis : Comparison of pathological and clinical parameters]

BACKGROUND

Bone marrow carcinosis is a sign of advanced tumor stage with nonspecific clinical and hematological symptoms. Diagnosis is based on bone marrow biopsy and histopathology, but biopsies are not part of the standard work-up in oncological diseases and data on the correlation between clinical presentation and pathological findings are sparse.

MATERIAL AND METHODS

In a retrospective single-center study, data from 20 tumor patients with bone marrow carcinosis were analyzed. Bone marrow biopsies were re-evaluated regarding quantity of tumor cells, fibrosis/necrosis, and bone changes. Immunohistochemistry of potential therapy-relevant receptors and PD-L1 was performed.

RESULTS

The median age in these 20 patients (13 women, 7 men) was 65 years. The most frequent diagnoses were breast (n = 8) and lung cancer (n = 5). Anemia (94% of patients), thrombocytopenia (72%), and elevated LDH (83%) were frequent findings. The degree of bone marrow infiltration was highly variable and accounted for between 1 and 95% of biopsy space. Significant bone remodeling was present in 14/20 biopsies. No correlation could be found between histological and radiological findings. Treated patients showed some clinical and biochemical improvement, but the overall survival was poor (median 4.5 months, range < 0.5 to 21.5 months).

DISCUSSION

Anemia and thrombocytopenia are frequently associated with bone marrow carcinosis, but are nonspecific. The extent of tumor cell infiltration and osteolytic/osteoblastic changes did not correlate with radiological findings. Therapy-relevant target factors should be evaluated, but therapeutic options are often limited and the prognosis is bad.