Too young to kill? U.S. Supreme Court treads a dangerous path in Roper v. Simmons

The death penalty remains an intensely divisive topic in American society. Recently, there has been a series of cases, first involving defendants with mental retardation and more recently involving juveniles, in which the U.S. Supreme Court has ruled by a five-to-four margin that the death penalty in both these classes violates the Constitution's prohibition against cruel and unusual punishment guaranteed in the Eighth Amendment. In this essay, I explore the Supreme Court's recent decision in Roper v. Simmons, a case involving juveniles. Besides a more general discussion of the Supreme Court's decision and the biting dissent led by Justice Scalia, I focus on the reliance on foreign authorities in the Court's decision. I submit that irrespective of the moral arguments against the death penalty, reliance on foreign authorities in interpreting the U.S. Constitution is a dangerous trend, as it has long-term sovereignty implications for the United States.     

Comparison of cardiac output in OPCAB: bolus thermodilution technique versus pulse contour analysis

The study was designed to evaluate the clinical agreement between intermittent bolus thermodilution technique and pulse contour analysis technique. Sixty patients with normal left ventricular function undergoing elective off-pump coronary bypass surgery were included in this prospective study. In addition to routine monitoring, a 7.5F pulmonary artery thermodilution catheter via right internal jugular vein and a 4F arterial thermodilution catheter into femoral artery were also placed. Cardiac output measurements were compared before induction, after induction, after sternotomy, during the various anastomoses, post-protamine and post-sternal closure. Statistical analysis was performed using analysis of agreement to assure bias distribution of differences between the two methods by using Bland and Altman analysis. The cardiac output values obtained at preinduction, post-induction, and post-sternal closure time points showed good agreement, whereas the values obtained during the various anastomoses showed significant differences (p <0.05). Therefore it was concluded that pulse contour analysis cannot be relied upon completely whenever there is a change in the position of heart or alteration in systemic vascular resistance. But the trends in cardiac output were in complete agreement during the entire procedure.     

Restoration of dysregulated CC chemokine signaling for monocyte/macrophage chemotaxis in head and neck squamous cell carcinoma patients by neem leaf glycoprotein maximizes tumor cell cytotoxicity

Previous studies have shown that the CC chemokine receptor CCR5 is downregulated on monocyte/macrophage (MO/Mφ) surfaces in head and neck squamous cell carcinoma (HNSCC) patients (stage IIIB). Ligands (RANTES, MIP-1α and MIP-1β) of this chemokine receptor were also secreted in lesser quantity from MO/Mφ of HNSCC patients in comparison with healthy individuals. In an aim to restore this dysregulated receptor–ligand signaling, we have used neem leaf glycoprotein (NLGP), a novel immunomodulator reported from our laboratory. NLGP upregulated CCR5 expression, as evidenced from studies on MO/Mφ of peripheral blood from HNSCC patients as well as healthy individuals. Expression of RANTES, MIP-1α and MIP-1β was also upregulated following NLGP treatment of these cells in vitro. Interestingly, NLGP has little effect on the expression of CCR5 and the ligand RANTES in oral cancer cells. This restored CCR5 receptor–ligand signaling seen in MO/Mφ was reflected in improved CCR5-dependent, p38 mitogen-activated protein kinase (MAPK)-mediated migration of MO/Mφ after NLGP treatment to a standard chemoattractant. NLGP also induces better antigen presentation and simultaneous costimulation to effector T cells by MO/Mφ by upregulating human leucocyte antigen (HLA)-ABC, CD80 and CD86. In addition, NLGP-treated MO/Mφ-primed T cells can effectively lyse tumor cells in vitro. The effects of NLGP on monocyte migration and T cell-mediated oral tumor cell killing were further demonstrated in transwell assays with or without CCR5 neutralization. These results suggest a new approach in cancer immunotherapy by modulating dysregulated CCR5 signals from MO/Mφ.     

Synthesis and recovery characteristics of branched and grafted PNIPAAm–PEG hydrogels for the development of an injectable load-bearing nucleus pulposus replacement

A family of injectable poly(N-isopropyl acrylamide) (PNIPAAm) copolymer hydrogels has been fabricated in order to tune mechanical properties to support load-bearing function and dimensional recovery for possible use as load-bearing medical devices, such as a nucleus pulposus replacement for the intervertebral disc. PNIPAAm–polyethylene glycol (PEG) copolymers were synthesized with varying hydrophilic PEG concentrations as grafted or branched structures to enhance dimensional recovery of the materials. Polymerizations were confirmed with attenuated total reflectance-Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy studies. Incorporation of PEG was effective in raising water content of pure PNIPAAm hydrogels (29.3% water for pure PNIPAAm vs. 47.7% for PEG branches and 39.5% for PEG grafts). PNIPAAm with 7% grafted as well as 7% branched PEG had significantly reduced compressive modulus compared to that of pure PNIPAAm. Initially recovered compressive strain was significantly increased for 7% PEG branches after pre-testing immersion in PBS for up to 33 days, while 7% PEG grafts decreased this value. Sample height recovery for pure PNIPAAm was limited to 31.6%, while PNIPAAm with 7% branches was increased to 71.3%. When mechanically tested samples were allowed to recover without load over 30 min, each composition was able to significantly recover height, indicating that the time to recovery is slower than the unloading rates typically used in testing. While the incorporation of hydrophilic PEG was expected to alter the mechanical behavior of the hydrogels, only the branched form was able to significantly enhance dimensional recovery.     

A new method for experimental characterisation of scattered radiation in 64-slice CT scanner

Purpose:

The consummate 64-slice CT scanner that spawns a new generation of non-invasive diagnostic tool, however revolutionary, brings with it the incidental by-product that is scattered radiation. The extended detector aperture capability in the 64-slcie CT scanner allows the effects of scattered radiation to be more pronounced and therefore demands that the magnitude and spatial distribution of scatter component be addressed during the imaging process. To this end, corrective algorithms need to be formulated on a basis of a precise understanding of scatter distribution. Relative to a 64-slice CT scanner, here now a unique solution is based upon dedicated blockers operative within various detector rows, calculating scatter profiles and scatter to primary ratios (SPR).

Materials and methods:

A single dimension blocker array was installed beneath the collimator, and the extrapolated shadow area on the detectors revealed the scatter radiation after exposure. The experiment was conducted using a 64-slice CT scanner manufactured by GE Healthcare Technologies.

Results:

Variables such as tube voltage, phantom size and phantom-off centring on the scatter profile and the SPR was measured using the dedicated blocker method introduced above. When tube voltage is increased from 80kVp to 140kVp in a 21.5 cm water phantom, the SPR is found to reduce from 219.9 to 39.9 respectively.

Conclusion:

The method developed within this study is applicable to any measurement and is direct with minimal complexity.     

Perceptual wind-up in the human oesophagus is enhanced by central sensitisation

BACKGROUND: Oesophageal acid infusion induces enhanced pain hypersensitivity in non-acid exposed upper oesophagus (secondary hyperalgesia) in patients with non-cardiac chest pain, thus suggesting central sensitisation contributes to visceral pain hypersensitivity in functional gut disorders (FGD). Perceptual wind-up (increased pain perception to constant intensity sensory stimuli at frequencies>or=0.3 Hz) is used as a proxy for central sensitisation to investigate pain syndromes where pain hypersensitivity is important (for example, fibromyalgia). AIMS: Wind-up in central sensitisation induced human visceral pain hypersensitivity has not been explored. We hypothesised that if wind-up is a proxy for central sensitisation induced human visceral pain hypersensitivity, then oesophageal wind-up should be enhanced by secondary hyperalgesia. METHODS: In eight healthy volunteers (seven males; mean age 32 years), perception at pain threshold to a train of 20 electrical stimuli applied to the hand and upper oesophagus (UO) at either 0.1 Hz (control) or 2 Hz was determined before and one hour after a 30 minute lower oesophageal acid infusion. RESULTS: Wind-up occurred only with the 2 Hz train in the UO and hand (both p=0.01). Following acid infusion, pain threshold decreased (17 (4)%; p=0.01) in the UO, suggesting the presence of secondary hyperalgesia. Wind-up to the 2 Hz train increased in the UO (wind-up ratio 1.4 (0.1) to 1.6 (0.1); p=0.03) but not in the hand (wind-up ratio 1.3 (0.1) and 1.3 (0.1); p=0.3) CONCLUSION: Enhanced wind-up after secondary oesophageal hyperalgesia suggests that visceral pain hypersensitivity induced by central sensitisation results from increased central neuronal excitability. Wind-up may offer new opportunities to investigate the contribution of central neuronal changes to symptoms in FGD.