ABSTRACT
Self-assembly of CuX2 (X- = BF4-, ClO4-, PF6-, and SbF6-) with a bidentate ethylmethylbis(3-pyridine)silane ligand (L) in the presence of additional polyatomic anions (X' = SiF62- and PF6-) gives rise to single crystals consisting of the X'@[Cu(II)3L6] cage motif. These cages exist as discrete or anion-bridged 3D networks depending on outside anions. The anion-bridged 3D networks interpenetrate in a four-fold fashion, and show, to our best knowledge, the most effective heterogeneous catalysis in 3,5-di-tert-butylcatechol oxidation reaction within 20 min at room temperature. Surprisingly, the heterogeneous catalysis is more effective than its corresponding homogeneous catalysis. Such notable catalytic effects can be explained by the maintenance of 3D inter-cage Cuâ¯Cu distance as a catalytic center.
ABSTRACT
A cyclic manipulation of peanut cage isomers has been achieved via anion exchange and unusual cage isomerism.
ABSTRACT
UNLABELLED: Total hip arthroplasties with hydroxyapatite coatings have shown encouraging results after early-term followup. We presumed hydroxyapatite-coating on a smooth hemispheric press-fit acetabular cup would enhance bone osseointegration and maintain stability of cup after midterm (minimum 5-year) followup. Sixty-three patients had 70 consecutive total hip arthroplasties. Five patients (eight hips) died from problems unrelated to surgery. The remaining patients (62 hips) were followed up for an average of 7 years (range, 6-9 years). The mean age of the patients was 49 years (range, 23-61 years). The average Harris hip score improved from 59 points (range, 32-82 points to 82 points (range, 37-100 points) at final followup. There were seven acetabular component revisions. Of the 55 unrevised cups, 47 hips (85%) were stable by bony ingrowth, five hips (9%) were fibrous stable, and three hips (5%) were unstable with cup migration. Osteolysis around the cup was observed in 18 hips (33%). The average polyethylene wear rate was 0.15 mm/year. Survival rates of the cups at 6 and 8 years were 94.3% and 60.5%, respectively. Total hip arthroplasties using an hydroxyapatite-coated smooth hemispheric acetabular cup showed an unexpected high failure rate in terms of fixation, occurrence of osteolysis, and revision after midterm followup. LEVEL OF EVIDENCE: Therapeutic study, Level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.
Subject(s)
Arthroplasty, Replacement, Hip/instrumentation , Coated Materials, Biocompatible , Durapatite , Hip Joint , Hip Prosthesis , Joint Instability/etiology , Acetabulum , Adult , Female , Follow-Up Studies , Humans , Joint Instability/surgery , Male , Middle Aged , Prosthesis Failure , Reoperation , Retrospective Studies , Time FactorsABSTRACT
Sixty-seven hips in 63 patients who underwent total hip arthroplasties with the use of the nonmodular cementless acetabular component and alumina-on-polyethylene bearing surface were available for complete clinical and radiographic review at a mean follow-up period of 7 (range 5-9) years. The mean age was 59 years (range 34-75) years. The mean preoperative Harris hip score of 50 points improved to 93 points at final follow-up. One (1.5%) hip required revision for a recurrent dislocation. No component was loose radiographically at final follow-up. The mean linear wear rate was 0.07 (range 0.01-0.23) mm/y. At a mean follow-up of 7 years, there was no aseptic loosening. Further follow-up, however, is necessary to determine the potential advantage of nonmodular acetabular component for the development of pelvic osteolysis.
Subject(s)
Arthroplasty, Replacement, Hip , Hip Prosthesis , Adult , Aged , Arthroplasty, Replacement, Hip/adverse effects , Cementation , Female , Follow-Up Studies , Hip Joint/diagnostic imaging , Hip Prosthesis/adverse effects , Humans , Male , Middle Aged , Prosthesis Design , Prosthesis Failure , Radiography , ReoperationABSTRACT
OBJECTIVE AND IMPORTANCE: Anterior endoscopic treatment of a huge anterior sacral meningocele, a rare example of spinal dysraphism, is described. CLINICAL PRESENTATION: A 43-year-old woman presented with severe headache and fever, increasing abdominal pain, and a several-year history of right lower-extremity radicular pain. She exhibited meningeal irritation signs and Currarino's triad. Lumbosacral myelograms and magnetic resonance imaging scans revealed a huge anterior sacral cyst connected with the spinal subarachnoid space. INTERVENTION: A straight rigid endoscope was introduced into the meningocele through a small abdominal incision. The fistula between the meningocele and the spinal subarachnoid space was obliterated with multiple fat grafts harvested from the abdomen. CONCLUSION: An anterior endoscopic procedure is an alternative for the treatment of a huge anterior sacral meningocele.
