Atypical femur fracture during bisphosphonate drug holiday: a case series

Recent studies have noted an increased risk of low energy subtrochanteric and femoral shaft fractures termed "atypical femur fractures" (AFFs) associated with long-term bisphosphonate use. As such, many clinicians have begun recommending a "drug holiday" to reduce the risks associated with long-term bisphosphonate use. We present two cases of AFFs occurring during a 4-year or greater drug holiday following long-term bisphosphonate use. These findings highlight the need to reevaluate optimal bisphosphonate therapy duration, dosage, as well as initiation and duration of a drug holiday with continued monitoring in the prevention of AFFs.

Genome-wide association study of perioperative myocardial infarction after coronary artery bypass surgery

OBJECTIVES

Identification of patient subpopulations susceptible to develop myocardial infarction (MI) or, conversely, those displaying either intrinsic cardioprotective phenotypes or highly responsive to protective interventions remain high-priority knowledge gaps. We sought to identify novel common genetic variants associated with perioperative MI in patients undergoing coronary artery bypass grafting using genome-wide association methodology.

SETTING

107 secondary and tertiary cardiac surgery centres across the USA.

PARTICIPANTS

We conducted a stage I genome-wide association study (GWAS) in 1433 ethnically diverse patients of both genders (112 cases/1321 controls) from the Genetics of Myocardial Adverse Outcomes and Graft Failure (GeneMAGIC) study, and a stage II analysis in an expanded population of 2055 patients (225 cases/1830 controls) combined from the GeneMAGIC and Duke Perioperative Genetics and Safety Outcomes (PEGASUS) studies. Patients undergoing primary non-emergent coronary bypass grafting were included.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome variable was perioperative MI, defined as creatine kinase MB isoenzyme (CK-MB) values ≥10× upper limit of normal during the first postoperative day, and not attributable to preoperative MI. Secondary outcomes included postoperative CK-MB as a quantitative trait, or a dichotomised phenotype based on extreme quartiles of the CK-MB distribution.

RESULTS

Following quality control and adjustment for clinical covariates, we identified 521 single nucleotide polymorphisms in the stage I GWAS analysis. Among these, 8 common variants in 3 genes or intergenic regions met p<10(-5) in stage II. A secondary analysis using CK-MB as a quantitative trait (minimum p=1.26×10(-3) for rs609418), or a dichotomised phenotype based on extreme CK-MB values (minimum p=7.72×10(-6) for rs4834703) supported these findings. Pathway analysis revealed that genes harbouring top-scoring variants cluster in pathways of biological relevance to extracellular matrix remodelling, endoplasmic reticulum-to-Golgi transport and inflammation.

CONCLUSIONS

Using a two-stage GWAS and pathway analysis, we identified and prioritised several potential susceptibility loci for perioperative MI.

Microwave-assisted telescoped cross metathesis-ring closing aza-Michael reaction sequence: step-economical access to nicotine–lobeline hybrid analogues

Step-economical access to nicotinic acetylcholine receptor ligands hybrids through an efficient telescoped cross-metathesis/cyclizing aza-Michael addition involving N-heteroaromatic olefinic derivatives.

Switchable stereocontrolled divergent synthesis induced by aza-Michael addition of deactivated primary amines under acid catalysis

Switchable tandem intramolecular aza-Michael/Michael and double aza-Michael reactions allow the oriented synthesis of highly functionalised cyclic skeletons. Conjugate addition of deactivated anilines triggers chemo- and stereo-divergent ring-closure reaction pathways with a striking selectivity depending on reaction conditions.

Patients' perceptions of health-related quality of life during and after adjuvant radiotherapy for T1N0M0 breast cancer

AIMS

The effects of radiotherapy on health-related quality of life (HRQOL) may influence decisions about adjuvant radiotherapy after breast-conserving surgery. We sought women's ratings of HRQOL during and after radiotherapy.

MATERIALS AND METHODS

Women completed HRQOL measures before, during and after adjuvant radiotherapy for node-negative, hormone receptor-positive breast cancers that were less than 2 cm in size. Acute and late toxicities were rated by clinicians.

RESULTS

There were 161 participants with a median age of 58 years (range 34-82). Mean scores for most aspects of HRQOL worsened only slightly during radiotherapy and improved to baseline levels or better within a few months. The symptoms rated as most distressing were: difficulty sleeping (29%), fatigue (23%), breast discolouration (21%), uncertainty about the future (18%), feeling sad or depressed (18%), feeling anxious or worried (19%). Most rated their experience as better (39%) or much better (28%) than expected. Grade 3 toxicities were rare (5% acute, 1% late) with no grade 4 toxicities.

CONCLUSIONS

Radiotherapy was associated with transient and generally mild impairments in a few aspects of HRQOL. Concerns about adverse effects on HRQOL should not weigh heavily on decisions about adjuvant breast radiotherapy.

Detrimental effects of acute hyperglycaemia on the rat heart

AIM

Hyperglycaemia is an important risk factor for acute myocardial infarction. It can lead to increased induction of non-oxidative glucose pathways (NOGPs) - polyol and hexosamine biosynthetic pathways, advanced glycation end products and protein kinase C - that may contribute to cardiovascular diseases onset. However, the precise underlying mechanisms remain poorly understood. Here we hypothesized that acute hyperglycaemia increases myocardial oxidative stress and NOGP activation resulting in cardiac dysfunction during ischaemia-reperfusion and that inhibition of, and/or shunting flux away from NOGPs [by benfotiamine (BFT) treatment], leads to cardioprotection.

METHODS

We employed several experimental systems: (i) Isolated rat hearts were perfused ex vivo with Krebs-Henseleit buffer containing 33 mm glucose vs. controls (11 mm glucose) ± global ischaemia and reperfusion ± BFT (first 20 min of reperfusion); (ii) Infarct size determination as per the ischaemic protocol, but with regional ischaemia and reperfusion ± BFT treatment; in separate experiments, NOGP inhibitors were also employed for (i) and (ii); and (iii) In vivo coronary ligations performed on streptozotocin-treated rats ± BFT treatment (early reperfusion).

RESULTS

Acute hyperglycaemia generated myocardial oxidative stress, NOGP activation and apoptosis, but caused no impairment of cardiac function during pre-ischaemia, thereby priming hearts for later damage. Following ischaemia-reperfusion (under hyperglycaemic conditions), such effects were exacerbated together with cardiac contractile dysfunction. Moreover, inhibition of respective NOGPs and shunting away by BFT treatment (in part) improved cardiac function during ischaemia-reperfusion.

CONCLUSION

Coordinate NOGP activation in response to acute hyperglycaemia results in contractile dysfunction during ischaemia-reperfusion, allowing for the development of novel cardioprotective agents.

Thermodynamic epimeric equilibration and crystallisation-induced dynamic resolution of lobelanine, norlobelanine and related analogues

The step-economical synthesis of lobelanine involving a ring closing double aza-Michael (RCDAM) reaction is revisited and successfully extended to the synthesis of various configurationally more stable analogues.

Influence of ureteric anastomosis technique on urological complications after kidney transplantation

The best technique for anastomosis of the donor ureter remains unresolved and an individual surgeon's preferred technique is likely to be based on training background. This retrospective analysis compares three ureteroneocystostomy techniques in 204 consecutive transplants with an overall ureteric complication rate of 7.3%. Ureteric complications after kidney transplantation present early, are more common when using deceased donor kidneys, and, require complex reconstructive surgery to resolve. Three significant and related findings have been demonstrated with a common theme related to the length of the transplanted ureter, and not, the debate over extravesical versus intravesical techniques.

Identification and frequency of circulating CD4(+) T lymphocytes specific to Benzylpenicillin in healthy donors

BACKGROUND

Drug hypersensitivity is known to rely on a drug-specific T-cell response. Amplitude of antigen-specific T-cell response is partly controlled by the size of the antigen-specific naïve CD4(+) T-cell repertoire, but estimate of this repertoire has never been investigated for allergenic drugs. The purpose of this study was to evaluate the frequency of benzylpenicillin-specific CD4(+) T lymphocytes in healthy donors.

METHODS

Co-cultures were established with CD4(+) T lymphocytes from healthy donors and mature autologous dendritic cells loaded with benzylpenicillin coupled to human serum albumin. CD4(+) T lymphocytes were stimulated once a week for 4 weeks with benzylpenicillin coupled to human serum albumin. The CD4(+) T-cell response was measured using an interferon-γ ELISPOT assay. Frequency of benzylpenicillin-specific naive CD4(+) T lymphocytes was then calculated using the Poisson distribution law.

RESULTS

Results showed the presence of benzylpenicillin-specific CD4(+) T lymphocytes in 9 of 10 tested healthy donors irrespective of their HLA typing, with a mean frequency of 0.29 cells per million of CD4(+) T cells. Experiments performed on naive (CD45RA(+) ) and on memory (CD45RO(+) ) CD4(+) T lymphocytes showed that these benzylpenicillin-specific CD4(+) T lymphocytes belonged to the naive T-cell subpopulation.

CONCLUSION

This study showed for the first time the existence of naive CD4(+) T lymphocytes specific to benzylpenicillin in healthy donors.