Intraoperative Infiltration of Liposomal Bupivacaine vs Bupivacaine Hydrochloride for Pain Management in Primary Total Hip Arthroplasty: A Prospective Randomized Trial

Background

Pain management after total hip arthroplasty is well studied. Nevertheless, there is no consensus regarding the “cocktail” to use in periarticular infiltration (PAI). Liposomal bupivacaine (LB) is a slow release local anesthetic that can be infiltrated during surgery. In this study, we compared LB to bupivacaine hydrochloride (HCL).

A signal transduction pharmacodynamic model of the kinetics of the parasympathomimetic activity of low-dose scopolamine and atropine in rats

We used a novel pharmacokinetic-pharmacodynamic (PK-PD) approach that had been applied for signal transduction kinetics to investigate the kinetics of the parasympathomimetic effect of scopolamine and atropine in rats. The parasympathetic tone was assessed by continuous measurement of the power of the high frequency band (HF) of electrocardiogram (ECG) R-R intervals obtained by power spectral analysis (PSA) of heart rate variability (HRV). To overcome the inherent noise of the HRV-HF data and to quantitatively identify temporal changes in the autonomic tone, a new approach of stepwise regression of the cumulative HF data was applied. The elevation of the parasympathetic tone occurred after a significant lag time (>70 min) following scopolamine administrations [0.25 and 0.5 mg/kg intravenous (iv) bolus or infusion over 100 min], followed by a gradual return to the baseline levels. A similar lag time in parasympathetic stimulation was observed following iv bolus administration of atropine (0.1 mg/kg). The plasma drug concentration versus time data were linked to the response versus time data using a signal transduction pharmacodynamic model that was fitted simultaneously to all four experimental data sets. This PK-PD model resolved the significant discrepancy between the concentration versus time and the response versus time patterns and successfully described the kinetics of the parasympathetic stimulation obtained for different drugs and different rates of administration. This work paves the way for further PK-PD preclinical investigations in this field.     

Epidemiologic, clinical, laboratory, and therapeutic characteristics of influenza A/H1N1 in Moslem Bedouin and Jewish children hospitalized in southern Israel during 2009

A total of 739 (225 H1N1(+)) children with a diagnosis of acute respiratory infection were hospitalized during July to December 2009. The H1N1(+) children were compared with 225 randomly enrolled H1N1(-) children with an influenza-like illness. As compared with influenza-like illness patients, patients with 2009 influenza A/H1N1 were characterized by older age, more vomiting, less hypoxemia and wheezing, lower white blood cell counts, less neutrophilia, and severe lymphopenia.     

Admission glucose,fasting glucose,HbA1c levels and the SYNTAX score in non-diabetic patients undergoing coronary angiography

Background

Pre-diabetic state is a major risk factor for the development of diabetes and cardiovascular events. Admission glucose, fasting glucose and HbA1c levels have an effect on prognosis in patients with pre-diabetes and in non-diabetic individuals. The aim of the present study was to investigate which of the following glucometabolic markers (admission glucose, fasting glucose and HbA1c levels) is correlated with the severity of coronary artery disease (CAD) in non-diabetic patients.

Methods

CAD severity according to SYNTAX score was prospectively evaluated in 226 non-diabetic patients hospitalized with myocardial infarction or stable angina and underwent coronary angiography. Glucose intolerance was assessed by serum admission glucose, fasting glucose and HbA1c levels. Logistic regression analysis was used to evaluate which glucometabolic factor has the strongest correlation with CAD severity.

Results

HbA1c was the only glucometabolic factor associated with SYNTAX score above 22 (OR = 3.03, CI 95 % 1.03–8.9, p = 0.04). HbA1c was also significantly associated with CAD severity in subgroup analysis (MI and stable angina).

Conclusions

In non-diabetic patients with myocardial infarction or stable angina, HbA1c levels correlate with CAD severity as measured by the SYNTAX score. No correlation was found between admission glucose or fasting glucose levels and CAD severity.     

Physical effects underlying the transition from primitive to modern cell membranes

To understand the emergence of Darwinian evolution, it is necessary to identify physical mechanisms that enabled primitive cells to compete with one another. Whereas all modern cell membranes are composed primarily of diacyl or dialkyl glycerol phospholipids, the first cell membranes are thought to have self-assembled from simple, single-chain lipids synthesized in the environment. We asked what selective advantage could have driven the transition from primitive to modern membranes, especially during early stages characterized by low levels of membrane phospholipid. Here we demonstrate that surprisingly low levels of phospholipids can drive protocell membrane growth during competition for single-chain lipids. Growth results from the decreasing fatty acid efflux from membranes with increasing phospholipid content. The ability to synthesize phospholipids from single-chain substrates would have therefore been highly advantageous for early cells competing for a limited supply of lipids. We show that the resulting increase in membrane phospholipid content would have led to a cascade of new selective pressures for the evolution of metabolic and transport machinery to overcome the reduced membrane permeability of diacyl lipid membranes. The evolution of phospholipid membranes could thus have been a deterministic outcome of intrinsic physical processes and a key driving force for early cellular evolution.