Ligand properties of boryl ligands in bis-boryl rhodium(III) complexes: a case study.

The oxidative addition of five diborane(4) derivatives, symmetrical and unsymmetrical, to [Rh(PMe)Cl] was studied. Only for the more electron poor diboron derivatives, Bcat, Bpin and catB-Bpin the resulting octahedral bis-boryl complexes [(PMe)Rh(boryl)Cl] were obtained, while for the more electron rich congeners only the equilibrium oxidative addition (catB-Bdmab) or no significant reaction (pinB-Bdmab) was observed (pin = (OCMe), cat = 1,2-OCH, dmab = 1,2-(NMe)CH). By abstraction of the chlorido ligand with NaBArF (BArF = tetrakis-[3,5-bis-(trifluormethyl)-phenyl]-borat) in the presence of a neutral ligand (L = PMe, MeCN, MeNC) the corresponding cationic octahedral complexes [(PMe)Rh(boryl)L] were obtained.

The 2021 Association Research Circulation Osseous Classification for Early-Stage Osteonecrosis of the Femoral Head to Computed Tomography-Based Study.

Background: The Association Research Circulation Osseous developed a novel classification for early-stage (precollapse) osteonecrosis of the femoral head (ONFH). We hypothesized that the novel classification is more reliable and valid when compared to previous 3 classifications: Steinberg, modified Kerboul, and Japanese Investigation Committee classifications.

Methods: In the novel classification, necrotic lesions were classified into 3 types: type 1 is a small lesion, where the lateral necrotic margin is medial to the femoral head apex; type 2 is a medium-sized lesion, with the lateral necrotic margin being between the femoral head apex and the lateral acetabular edge; and type 3 is a large lesion, which extends outside the lateral acetabular edge.

N-H deprotonation of a diaminodialkoxido diborane(4) - a structural study on bifunctional Lewis acids/bases and their dimerisation to B(sp)B(sp)N six membered rings.

The N-H deprotonation of the diaminodialkoxido diborane(4) pinB-Bdab (1) (pin: (OCMe), dab: 1,2-(NH)CH), is crucial for the electrophilic -functionalisation towards unsymmetrical diborane(4) reagents. An N-H deprotonated diborane(4) comprises Lewis basic nitrogen atoms and at the same time Lewis acidic boron atoms. This bifunctionality governs its reactivity and structural chemistry.

Osteonecrosis of the Femoral Head: an Updated Review of ARCO on Pathogenesis, Staging and Treatment.

Non-traumatic osteonecrosis of the femoral head (ONFH) usually affects adults younger than 50 years and frequently leads to femoral head collapse and subsequent arthritis of the hip. It is becoming more prevalent along with increasing use of corticosteroids for the adjuvant therapy of leukemia and other myelogenous diseases as well as management of organ transplantation. This review updated knowledge on the pathogenesis, classification criteria, staging system, and treatment of ONFH.

Diagnosis and Treatment of Femoral Head Osteonecrosis: A Protocol for Development of Evidence-Based Clinical Practice Guidelines.

Introduction: There are many treatment options for patients who have osteonecrosis of the femoral head (ONFH) and management strategies vary widely both among and within individual countries. Although many researchers have attempted to elucidate the optimal strategies for managing this disease, the lack of large-scale randomized control trials and the lack of agreement on disease staging have curtailed the development of clear-cut guidelines.

Materials And Methods: The Association Research Circulation Osseous (ARCO) group sought to address three questions for the management of patients who have ONFH: 1) What imaging studies are most sensitive and specific for the diagnostic evaluation of patients who have ONFH?; 2) What is the best treatment strategy for preventing disease progression in patients who have pre-collapse lesions?; and 3) What is the best treatment strategy for patients who have post-collapse disease? The Patient, Intervention, Comparison, and Outcome (PICO) format was used to formulate the search strategy for each research question.