Impact of hypotension after return of spontaneous circulation on survival in patients of out-of-hospital cardiac arrest

Objective

To investigate the relationship between hypotension in the first 3 h after return of spontaneous circulation (ROSC) in patients with out-of-hospital cardiac arrest.

Evidence for Elizabethkingia anophelis Transmission from Mother to Infant,Hong Kong

Elizabethkingia anophelis, recently discovered from mosquito gut, is an emerging bacterium associated with neonatal meningitis and nosocomial outbreaks. However, its transmission route remains unknown. We use rapid genome sequencing to investigate 3 cases of E. anophelis sepsis involving 2 neonates who had meningitis and 1 neonate’s mother who had chorioamnionitis. Comparative genomics revealed evidence for perinatal vertical transmission from a mother to her neonate; the 2 isolates from these patients, HKU37 and HKU38, shared essentially identical genome sequences. In contrast, the strain from another neonate (HKU36) was genetically divergent, showing only 78.6% genome sequence identity to HKU37 and HKU38, thus excluding a clonal outbreak. Comparison to genomes from mosquito strains revealed potential metabolic adaptations in E. anophelis under different environments. Maternal infection, not mosquitoes, is most likely the source of neonatal E. anophelis infections. Our findings highlight the power of genome sequencing in gaining rapid insights on transmission and pathogenesis of emerging pathogens.     

EDG1 receptor stimulation leads to cardiac hypertrophy in rat neonatal myocytes

Sphingosine 1 phosphate (S1P), an aminophospholipid, acts extracellularly as a ligand via the specific G protein-coupled receptors of the endothelial differentiation gene (EDG) 1, 3, 5, 6 and 8 receptors family and intracellularly as a second messenger in various cellular types. The aim of this work was to investigate biological activity of S1P in cardiomyocytes with respect to related sphingolipids. S1P was applied for 48 h on rat neonatal cardiomyocytes at 10 nM, 100 nM and 1 microM. S1P induced a concentration-dependent cellular hypertrophy evidenced by an increase in cell size, [3H]-phenylalanine incorporation, protein content and Brain Natriuretic Peptide (BNP) secretion. Among the lipids tested S1P exhibits the lower EC50 (67 nM) followed by dihydro-S1P (107 nM) and sphingosylphosphorylcholine (1.6 microM). The effect of S1P could be related to a stimulation of the EDG1 receptor since we showed that the EDG1 receptor is predominantly expressed at the mRNA and protein levels in rat cardiomyocytes and that specific anti-EDG1 antibodies inhibited the hypertrophic effect induced by S1P. Furthermore the expression level of most other EDG receptors for S1P appeared very low in cardiac myocytes. S1P (100 nM) increased the phosphorylation of p42/44MAPK, p38MAPK, JNK, Akt and p70(S6K), this effect being reversed by inhibitors of their respective phosphorylation which also rescue the hypertrophic phenotype. Finally, S1P stimulated actin stress fibre formation reverted by the Rho inhibitor, the C3 exoenzyme. Altogether, our results show that S1P induces cardiomyocyte hypertrophy mainly via the EDG1 receptor and subsequently via Gi through ERKs, p38 MAPK, JNK, PI3K and via Rho pathway.     

Hemoptysis as an unusual presenting symptom of invasion of a descending thoracic aortic aneurysmal dissection by lung cancer

A 70-year-old woman with a known chronic dissecting aneurysm of the descending thoracic aorta presented with new-onset back pain and hemoptysis. The hemoptysis was thought to be the result of invasion of the bronchial tree by the aneurysm. During surgical repair, a lesion that appeared to be a pulmonary abscess was discovered to be adhering to the aortic tissue, and the patient underwent a localized pulmonary resection. The pathology report of the surgical specimens revealed squamous cell carcinoma of the lung with infiltration of the aortic wall. The patient died of lung cancer 6 months later. Hemoptysis was an unusual presentation in a case of lung cancer that had invaded a stable chronic aortic aneurysm.     

A versatile technique for aortic root replacement without pre-manufactured composite graft: a 12-year experience

BACKGROUND AND AIM OF THE STUDY: Replacement of the aortic root is the treatment of choice for aneurysmal dilatation. Many modifications of the Bentall technique have been described, as have valve-sparing procedures. The study aim was to determine the outcome of a versatile modification of composite replacement that has been adopted over the past 12 years. Separate graft and prosthetic valve components were used to allow freedom of valve choice and the use of an appropriately sized graft for the distal aortic anastomosis. METHODS: Between January 1990 and March 2002, 59 patients (45 males, 14 females; mean age 56 +/- 14 years) underwent aortic root replacement using this technique. Indications for surgery were elective in 35 patients and emergent (usually type A aortic dissection) in 24. The range of valve prostheses used, their size, and the size of aortic graft used in each case was assessed. Durations of ischemia and cardiopulmonary bypass were recorded, as was postoperative blood loss and subsequent patient progress, including valve-related events, perioperative mortality and actuarial survival. RESULTS: A wide range of aortic graft sizes was combined with both mechanical and tissue valves (from 1-7 mm larger in diameter). Median postoperative blood loss was 550 ml (IQR 400-800 ml). Perioperative mortality was 5.1%. There were no valve- or technique-related deaths, and the median actuarial survival was 13.17 years. During a 12-year follow up there were no proximal aortic reoperations. CONCLUSIONS: This technique had favorable perioperative mortality, produced a secure proximal suture line, and allowed the surgeon free choice of both valve type and size of aortic graft. This minimized tension at the distal suture line, and produced good hemostasis, especially in those patients with fragile dissected tissues.     

Amyloid and metabolic positron emission tomography imaging of cognitively normal adults with Alzheimer's parents

This study examines the relationship between fibrillar beta-amyloid (Aβ) deposition and reduced glucose metabolism, a proxy for neuronal dysfunction, in cognitively normal (NL) individuals with a parent affected by late-onset Alzheimer's disease (AD). Forty-seven 40–80-year-old NL received positron emission tomography (PET) with ¹¹C-Pittsburgh compound B (PiB) and 18F-fluoro-2-deoxy-d-glucose (FDG). These included 19 NL with a maternal history (MH), 12 NL with a paternal history (PH), and 16 NL with negative family history of AD (NH). Automated regions of interest, statistical parametric mapping, voxel-wise intermodality correlations, and logistic regressions were used to examine cerebral-to-cerebellar PiB and FDG standardized uptake value ratios across groups. The MH group showed higher PiB retention and lower metabolism in AD regions compared with NH and PH, which were negatively correlated in posterior cingulate, frontal, and parieto-temporal regions (Pearson r ≤ −0.57, p ≤ 0.05). No correlations were observed in NH and PH. The combination of Aβ deposition and metabolism yielded accuracy ≥ 69% for MH vs. NH and ≥ 71% for MH vs. PH, with relative risk = 1.9–5.1 (p values < 0.005). NL individuals with AD-affected mothers show co-occurring Aβ increases and hypometabolism in AD-vulnerable regions, suggesting an increased risk for AD.     

Integration of light scattering with machine learning for label free cell detection

Light scattering has been used for label-free cell detection. The angular light scattering patterns from the cells are unique to them based on the cell size, nucleus size, number of mitochondria, and cell surface roughness. The patterns collected from the cells can then be classified based on different image characteristics. We have also developed a machine learning (ML) method to classify these cell light scattering patterns. As a case study we have used this light scattering technique integrated with the machine learning to analyze staurosporine-treated SH-SY5Y neuroblastoma cells and compare them to non-treated control cells. Experimental results show that the ML technique can provide a classification accuracy (treated versus non-treated) of over 90%. The predicted percentage of the treated cells in a mixed solution is within 5% of the reference (ground-truth) value and the technique has the potential to be a viable method for real-time detection and diagnosis.