Cemented humeral stem versus press-fit humeral stem in total shoulder arthroplasty: a systematic review and meta-analysis.

AIMS: The aim of this study was to evaluate the differences in revision and complication rates, functional outcomes, and radiological outcomes between cemented and press-fit humeral stems in primary anatomical total shoulder arthroplasty (TSA). MATERIALS AND METHODS: A comprehensive systematic review and meta-analysis was conducted searching for studies that included patients who underwent primary anatomical TSA for primary osteoarthritis or rheumatoid arthritis. RESULTS: There was a total of 36 studies with 927 cemented humeral stems and 1555 press-fit stems. The revision rate was 5.4% (95% confidence interval (CI) 3.9 to 7.4) at a mean of 89 months for cemented stems, and 2.4% (95% CI 1.1 to 4.7) at a mean of 40 months for press-fit stems. A priori subgroup analysis to control for follow-up periods demonstrated similar revision rates: 2.3% (95% CI 1.1 to 4.7) for cemented stems versus 1.8% (95% CI 1.4 to 2.9) for press-fit stems. Exploratory meta-regression found that longer follow-up was a moderating variable for revision (p = 0.003). CONCLUSION: Cement fixation had similar revision rates when compared to press-fit stems at short- to midterm follow-up. Rotator cuff pathology was a prevalent complication in both groups but is likely not related to fixation type. Overall, with comparable revision rates, possible easier revision, and decreased operative time, humeral press-fit fixation may be an optimal choice for primary anatomical TSA in patients with sufficient bone stock. Cite this article: Bone Joint J 2019;101-B:1107-1114.

Development of a platform to evaluate and limit in-stent restenosis.

The objective of this work was to develop a platform to evaluate and deliver putative therapeutic agents for in-stent restenosis. Arterial stenting is applied in more than 60% of balloon angioplasties for treating cardiovascular disease. However, stented arteries encounter accelerated rates of restenosis. No prior platform has allowed evaluation or local management of in-stent restenosis without perturbing the very system being examined. A stainless steel, balloon-expandable stent was modified to serve as an ablumenal drug delivery platform. Several combinations of bioerodible polymer microspheres and gels were evaluated for channel retention under in vitro flow and in vivo conditions. A stent-anchored hybrid system prevented material embolization under all conditions. Unlike prior platforms, these stents do not alter local inflammation or in-stent plaque formation relative to conventional Palmaz-Schatz stents after in vivo deployment. The system also proved sensitive enough to detect plaque reduction with an antirestenotic agent. We conclude that a platform to evaluate and deliver therapeutic agents for in-stent restenosis has been achieved.

Temporary hair removal in patients with hirsutism: a clinical study.

Women with facial hirsutism are burdened with hairs that often interfere with personal and work activities. Temporary hair removal is a major component in the management of hirsute patients. From a caseload of 1,000 patients, we submitted questionnaires to 271 and interviewed 135. We found that shaving was the most helpful and most frequently used temporary method. Judicious plucking can be helpful if tolerated, but care must be taken to avoid folliculitis, pigmentation, and scarring. Waxing and depilatories were used by less than 6 percent of patients on the face and by about 20 percent on other parts of the body. The avoidance of irritants and the use of hydrocortisone 1 percent cream are important in the management of any irritation due to hair removal techniques. Cosmetic coverups may be helpful.

Crystal structure of the Dbl and pleckstrin homology domains from the human Son of sevenless protein.

Proteins containing Dbl homology (DH) domains activate Rho-family GTPases by functioning as specific guanine nucleotide exchange factors. All known DH domains have associated C-terminal pleckstrin homology (PH) domains that are implicated in targeting and regulatory functions. The crystal structure of a fragment of the human Son of sevenless protein containing the DH and PH domains has been determined at 2.3 A resolution. The entirely alpha-helical DH domain is unrelated in architecture to other nucleotide exchange factors. The active site of the DH domain, identified on the basis of sequence conservation and structural features, lies near the interface between the DH and PH domains. The structure suggests that ligation of the PH domain will be coupled structurally to the GTPase binding site.

Crystallographic analysis of the recognition of a nuclear localization signal by the nuclear import factor karyopherin alpha.

Selective nuclear import is mediated by nuclear localization signals (NLSs) and cognate transport factors known as karyopherins or importins. Karyopherin alpha recognizes "classical" monopartite and bipartite NLSs. We report the crystal structure of a 50 kDa fragment of the 60 kDa yeast karyopherin alpha, in the absence and presence of a monopartite NLS peptide at 2.2 A and 2.8 A resolution, respectively. The structure shows a tandem array of ten armadillo repeats, organized in a right-handed superhelix of helices. Binding of the NLS peptide occurs at two sites within a helical surface groove that is lined by conserved residues. The structure reveals the determinants of NLS specificity and suggests a model for the recognition of bipartite NLSs.

Mass spectral analysis of complex lipids desorbed directly from lyophilized membranes and cells.

Three desorption ionization techniques--laser desorption, plasma desorption and fast atom bombardment mass spectrometry--have been applied to lyophilized cells, membranes, lysed cells and various extracts. It has been shown that intact polar lipids are selectively desorbed from biological membranes by these methods and that their mass spectra provide "fingerprints" which reflect the unique biochemical composition of each class of cell or membrane.