Predictors of death during 10 years after coronary artery bypass grafting with particular emphasis on age

OBJECTIVES: To describe predictors of death during 10 years of follow-up after coronary artery bypass grafting (CABG); to evaluate whether age interacts with the influence of various predictors on outcome; and to compare the mortality during 10 years after CABG with the mortality in an age- and sex-matched control population. DESIGN: Prospective, observational study. SETTING: Department of Thoracic and Cardiovascular Surgery at Sahlgrenska University Hospital and Scandinavian Heart Centre in G?teborg, Sweden. PARTICIPANTS: All patients from western Sweden who underwent CABG between 1 June 1988 and 1 June 1991 without simultaneous valve surgery and with no previous CABG. MAIN OUTCOME MEASUREMENTS: All-cause mortality during 10 years but more than 30 days after CABG. RESULTS: In all, 2000 patients participated in the survey. The following factors appeared as independent predictors of death: preoperative factors-age, history of congestive heart failure, cerebrovascular disease, history of intermittent claudication, current smoking, degree of left ventricular impairment, valvular disease and duration of angina pectoris; peroperative factors-ventilator time and neurological complications; postoperative factors-arrhythmia, requirement of digitalis and requirement of antidiabetics. There was an interaction between age and history of cerebrovascular disease with a stronger impact on outcome in younger patients. The late (>30 days after CABG) 10-year mortality in the study cohort was 29.6% compared with 25.9% in the control population (P=0.02). CONCLUSION: Among patients who underwent CABG, 13 independent predictors for mortality were found, mainly among preoperative factors but also among peroperative factors, postoperative complications and medication requirement after CABG.     

Incident diabetes mellitus may explain the association between sleep duration and incident coronary heart disease

Aims/hypothesis

Sleep duration is a risk factor for incident diabetes mellitus and CHD. The primary aim of the present study was to investigate, in sex-specific analyses, the role of incident diabetes as the possible biological mechanism for the reported association between short/long sleep duration and incident CHD. Considering that diabetes is a major risk factor for CHD, we hypothesised that any association with sleep duration would not hold for cases of incident CHD occurring before incident diabetes (‘non-diabetes CHD’) but would hold true for cases of incident CHD following incident diabetes (‘diabetes-CHD’).

Methods

A total of 6966 men and 9378 women aged 45–73 years from the Malmö Diet Cancer Study, a population-based, prospective cohort, who had answered questions on habitual sleep duration and did not have a history of prevalent diabetes or CHD were included in the analyses. Incident cases of diabetes and CHD were identified using national registers. Sex-specific Cox proportional hazards regression models were stratified by BMI and adjusted for known covariates of diabetes and CHD.

Results

Mean follow-up times for incident diabetes (n = 1137/1016 [men/women]), incident CHD (n = 1170/578), non-diabetes CHD (n = 1016/501) and diabetes-CHD (n = 154/77) were 14.2–15.2 years for men, and 15.8–16.5 years for women. In men, short sleep duration (< 6 h) was associated with incident diabetes (HR 1.35, 95% CI 1.01, 1.80), CHD (HR 1.41, 95% CI 1.06, 1.89) and diabetes-CHD (HR 2.34, 95% CI 1.20, 4.55). Short sleep duration was not associated with incident non-diabetes CHD (HR 1.35, 95% CI 0.98, 1.87). Long sleep duration (≥ 9 h) was associated with incident diabetes (HR 1.37, 95% CI 1.03, 1.83), CHD (HR 1.33, 95% CI 1.01, 1.75) and diabetes-CHD (HR 2.10, 95% CI 1.11, 4.00). Long sleep duration was not associated with incident non-diabetes CHD (HR 1.33, 95% CI 0.98, 1.80). In women, short sleep duration was associated with incident diabetes (HR 1.53, 95% CI 1.16, 2.01), CHD (HR 1.46, 95% CI 1.03, 2.07) and diabetes-CHD (HR 2.88, 95% CI 1.37, 6.08). Short sleep duration was not associated with incident non-diabetes CHD (HR 1.29, 95% CI 0.86, 1.93).

Conclusions/interpretation

The associations between sleep duration and incident CHD directly reflect the associations between sleep duration and incident diabetes. Incident diabetes may thus be the explanatory mechanism for the association between short and long sleep duration and incident CHD.

     

The PAS positive material in gastric cancer cells of signet ring type is not mucin

Purpose

The purpose of this study is to assess the exocrine and neuroendocrine properties of tumour cells in diffuse gastric cancer with signet ring cell differentiation.

Material and methods

Mucin mRNA and protein expressions (MUC1, 2, 3, 4, 5AC, 6 and MUC13) were assessed by immunohistochemistry and in situ hybridization. The neuroendocrine properties were evaluated by protein and mRNA expression of the general neuroendocrine markers chromogranin A and synaptophysin.

Results

No MUC expression was observed in signet ring tumour cells including the amorphous substance in any of the nine cases. All cases showed immunoreactivity to synaptophysin, and seven out of nine cases immunoreactivity to chromogranin A in signet ring and non-signet ring tumour cells. Chromogranin A mRNA expression was observed in tumour cells in all samples with retained mRNA.

Conclusions

The lack of MUC protein and mRNA in signet ring tumour cells suggests the amorphous substance is not mucin. The lack of MUC mRNA expression in non-signet ring tumour cells questions exocrine differentiation in this tumour group. The abundant protein expression of the general neuroendocrine markers CgA and synaptophysin, and mRNA expression in tumour cells strengthens the hypothesis that this tumour group may be of neuroendocrine origin.     

Differences in cardiovascular safety with non‐steroidal anti‐inflammatory drug therapy—A nationwide study in patients with osteoarthritis

Osteoarthritis (OA) and the non‐steroidal anti‐inflammatory drugs (NSAIDs) used to relieve OA‐associated pain have been linked independently to increased cardiovascular risk. We examined the risk of cardiovascular events associated with NSAID use in patients with OA. We employed linked nationwide administrative registers to examine NSAID use between 1996 and 2015 by Danish patients with OA aged ≥18 years. Using adjusted Cox proportional hazard analyses, we calculated the risk of the composite outcome of cardiovascular death, non‐fatal myocardial infarction and non‐fatal ischaemic stroke/TIA, and of each outcome separately, up to 5 years after OA diagnosis. Of 533 502 patients included, 64.3% received NSAIDs and 38 226 (7.2%) experienced a cardiovascular event during follow‐up. Compared with non‐use, all NSAIDs were associated with increased risk of the composite outcome: hazard ratio (HR) for rofecoxib, 1.90 (95% confidence interval, 1.74‐2.08); celecoxib, 1.47 (1.34‐1.62); diclofenac, 1.44 (1.36‐1.54); ibuprofen, 1.20 (1.15‐1.25); and naproxen, 1.20 (1.04‐1.39). Similar results were seen for each outcome separately. When celecoxib was used as reference, ibuprofen (HRs: 0.81 [CI: 0.74‐0.90]) and naproxen (HRs: 0.81 [0.68‐0.97]) exhibited a lower cardiovascular risk, even when low doses were compared. Low‐dose naproxen and ibuprofen were associated with the lowest risks of the composite outcome compared to no NSAID use: HRs: 1.12 (1.07‐1.19) and 1.16 (0.92‐1.42), respectively. In patients with OA, we found significant differences in cardiovascular risk among NSAIDs. Naproxen and ibuprofen appeared to be safer compared to celecoxib, also when we examined equivalent low doses. In terms of cardiovascular safety, naproxen and ibuprofen, at the lowest effective doses, may be the preferred first choices among patients with OA needing pain relief.     

Neuronal calcium-binding proteins 1/2 localize to dorsal root ganglia and excitatory spinal neurons and are regulated by nerve injury

Neuronal calcium (Ca²⁺)-binding proteins 1 and 2 (NECAB1/2) are members of the phylogenetically conserved EF-hand Ca²⁺-binding protein superfamily. To date, NECABs have been explored only to a limited extent and, so far, not at all at the spinal level. Here, we describe the distribution, phenotype, and nerve injury-induced regulation of NECAB1/NECAB2 in mouse dorsal root ganglia (DRGs) and spinal cord. In DRGs, NECAB1/2 are expressed in around 70% of mainly small- and medium-sized neurons. Many colocalize with calcitonin gene-related peptide and isolectin B4, and thus represent nociceptors. NECAB1/2 neurons are much more abundant in DRGs than the Ca²⁺-binding proteins (parvalbumin, calbindin, calretinin, and secretagogin) studied to date. In the spinal cord, the NECAB1/2 distribution is mainly complementary. NECAB1 labels interneurons and a plexus of processes in superficial layers of the dorsal horn, commissural neurons in the intermediate area, and motor neurons in the ventral horn. Using CLARITY, a novel, bilaterally connected neuronal system with dendrites that embrace the dorsal columns like palisades is observed. NECAB2 is present in cell bodies and presynaptic boutons across the spinal cord. In the dorsal horn, most NECAB1/2 neurons are glutamatergic. Both NECAB1/2 are transported into dorsal roots and peripheral nerves. Peripheral nerve injury reduces NECAB2, but not NECAB1, expression in DRG neurons. Our study identifies NECAB1/2 as abundant Ca²⁺-binding proteins in pain-related DRG neurons and a variety of spinal systems, providing molecular markers for known and unknown neuron populations of mechanosensory and pain circuits in the spinal cord.Calcium (Ca²⁺) plays a crucial role in many and diverse cellular processes, including neurotransmission (1). Glutamate and neuropeptides are neurotransmitters released from the central terminals of dorsal root ganglion (DRG) neurons in the spinal dorsal horn, where signals for different sensory modalities, including pain, are conveyed to higher centers (2–12). Neurotransmitter release is tightly regulated by Ca²⁺-dependent SNARE proteins whose activity is regulated by Ca²⁺-binding proteins (CaBPs) (1, 7, 13).Parvalbumin (PV), calbindin D-28K (CB), calretinin (CR), and secretagogin (Scgn) are extensively studied EF-hand CaBPs, and they have also emerged as valuable anatomical markers for morphologically and functionally distinct neuronal subpopulations (14–17). The expression of CaBPs in DRG neurons has been thoroughly studied (18). Moreover, neuronal Ca²⁺ sensor 1 and downstream regulatory element-antagonist modulator (DREAM) are also EF-hand Ca²⁺-binding proteins in DRGs and the spinal cord (19, 20). Despite these advances, a CaBP has so far not been characterized in the majority of small- and medium-sized DRG neurons, many of which represent nociceptors.The subfamily of neuronal Ca²⁺-binding proteins (NECABs) consists of three members (NECAB1–NECAB3), probably as a result of gene duplication (21). NECABs are also EF-hand proteins, with one pair of EF-hand motifs in the N terminus and a putative antibiotic biosynthesis monooxygenase domain in the C terminus, which are linked by a NECAB homogeneous region (22). NECAB1/2 are restricted to the nervous system, whereas NECAB3 is also expressed in the heart and skeletal muscle (21).NECAB1 was first identified as the target protein of synaptotagmin I C2A-domain by affinity chromatography, with its expression restricted to layer 4 cortical pyramidal neurons, inhibitory interneurons, and hippocampal CA2 pyramidal cells in mouse brain (21, 23). The gene of the second member was cloned from mouse and initially named Necab. It encodes a 389-aa (NECAB2) (24). NECAB2 was identified as a downstream target of Pax6 in mouse retina, which is involved in retinal development (24, 25), as well as being a binding partner for the adenosine A_2A receptor (22). Furthermore, an interaction between NECAB2 and metabotropic glutamate receptor 5 (mGluR5) was demonstrated in rat hippocampal pyramidal cells, possibly regulating mGluR5’s coupling to its signaling machinery (26). Finally, NECAB3, also known as XB51, was isolated as an interacting target for the neuron-specific X11-like protein and is possibly involved in the pathogenesis of Alzheimer’s disease (27, 28).Very recently, NECAB1/2 were shown to have complementary expression patterns in mouse hippocampus at the mRNA and protein levels, whereas NECAB3 is broadly distributed in the hippocampus (29). NECAB1-expressing cells were seen throughout the cell-sparse layers of Ammon’s horn and the hilus of the dentate gyrus. In contrast, NECAB2 is enriched in pyramidal cells of the CA2 region. A minority of NECAB1⁺ neurons were GABAergic yet did not coexpress PV, CB, or CR (29).Here, we investigated the expression of NECAB1/2 in mouse DRGs and spinal cord using quantitative PCR (qPCR), immunohistochemistry (also combined with CLARITY) (30), and Western blotting. We compared the distribution of NECABs with that of the four CaBPs restricted to neurons, PV, CB, CR, or Scgn. NECAB⁺ neurons in the spinal dorsal horn were phenotyped using transgenic mice harboring genetic markers for excitatory [vesicular glutamate transporter 2 (VGLUT2)] (31) or inhibitory [glutamate decarboxylase 67 (GAD67)] (32) cell identities. Finally, the effect of peripheral nerve injury was analyzed.     

Human stem cell models of neurodegeneration: a novel approach to study mechanisms of disease development

The number of patients with neurodegenerative diseases is increasing significantly worldwide. Thus, intense research is being pursued to uncover mechanisms of disease development in an effort to identify molecular targets for therapeutic intervention. Analysis of postmortem tissue from patients has yielded important histological and biochemical markers of disease progression. However, this approach is inherently limited because it is not possible to study patient neurons prior to degeneration. As such, transgenic and knockout models of neurodegenerative diseases are commonly employed. While these animal models have yielded important insights into some molecular mechanisms of disease development, they do not provide the opportunity to study mechanisms of neurodegeneration in human neurons at risk and thus, it is often difficult or even impossible to replicate human pathogenesis with this approach. The generation of patient-specific induced pluripotent stem (iPS) cells offers a unique opportunity to overcome these obstacles. By expanding and differentiating iPS cells, it is possible to generate large numbers of functional neurons in vitro, which can then be used to study the disease of the donating patient. Here, we provide an overview of human stem cell models of neurodegeneration using iPS cells from patients with Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, frontotemporal dementia, Huntington’s disease, spinal muscular atrophy and other neurodegenerative diseases. In addition, we describe how further refinements of reprogramming technology resulted in the generation of patient-specific induced neurons, which have also been used to model neurodegenerative changes in vitro.