Comparative electrophysiological evaluation of hippocampal function following repeated inhalation exposures to JP-8, Jet A,JP-5, and the synthetic Fischer Tropsch fuel

Exposure to fuels continues to be a concern in both military and general populations. The aim of this study was to examine effects of in vivo rat repeated exposures to different types of jet fuel utilizing microelectrode arrays for comparative electrophysiological (EP) measurements in hippocampal slices. Animals were exposed to increasing concentrations of four jet fuels, Jet Propellant (JP)-8, Jet A, JP-5, or synthetic Fischer Tropsch (FT) fuel via whole-body inhalation for 20 d (6 hr/d, 5 d/week for 28 d) and synaptic transmission as well as behavioral performance were assessed. Our behavioral studies indicated no significant changes in behavioral performance in animals exposed to JP-8, Jet A, or JP-5. A significant deviation in learning pattern during the Morris water maze task was observed in rats exposed to the highest concentration of FT (2000 mg/m³). There were also significant differences in the EP profile of hippocampal neurons from animals exposed to JP-8, Jet A, JP-5, or FT compared to control air. However, these differences were not consistent across fuels or dose dependent. As expected, patterns of EP alterations in brain slices from JP-8 and Jet A exposures were more similar compared to those from JP-5 and FT. Further longitudinal investigations are needed to determine if these EP effects are transient or persistent. Such studies may dictate if and how one may use EP measurements to indicate potential susceptibility to neurological impairments, particularly those that result from inhalation exposure to chemicals or mixtures.     

Caregiving and cardiovascular disease risk factors in male and female Luo elders from Kenya

Background: The HIV/AIDS pandemic has created over 11 million orphans, who are primarily being cared for by grandparents. It has been suggested that this renewed parenting responsibility presents elders with added stressors. Few studies have systematically examined the impact of caregiving on health outcomes.

Aim: The aim of this study was to examine the impact of caregiving on cardiovascular risk. It was hypothesized that caregiving would increase cardiovascular disease risk as measured by Framingham risk scores.

Subjects and method: 386 Luo elders (age = 73±8), divided into caregiving and non-caregiving groups, were recruited from the Nyanza Province, Kenya. Data were obtained from the participants including: Total cholesterol, HDL cholesterol, glucose, blood pressure, age, sex and smoking status.

Results: No significant difference was found between the Framingham risk scores of caregivers and non-caregivers. Among women increased BMI was positively associated with Framingham score (p=0.017), and among men increased waist circumference was positively associated with the score (p<0.001). Among women, the number of orphans under one's care lowered the risk of falling into the top quartile of the Framingham score while being a caregiver increased the risk of falling into the top quartile.

Conclusion: This study demonstrates that there is not a simple relationship between caregiving and cardiovascular risk.     

Has Tranexamic Acid in Total Knee Arthroplasty Made Tourniquet Use Obsolete?

The application of tranexamic acid (TXA) in total joint arthroplasty has dramatically improved peri-operative blood management. In light of these benefits, a study by Huang et al., “Intravenous and Topical Tranexamic Acid Alone Are Superior to Tourniquet Use for Primary Total Knee Arthroplasty,” evaluates the need for continued use of the intra-operative tourniquet, which remains a routine practice with documented benefits and adverse effects. This review evaluates the study’s design and critically interprets its findings for clinical practice. Through a prospective, randomized trial, Huang et al. demonstrated that among selected patients undergoing primary total knee arthroplasty, the use of a tourniquet results in no reduction in blood loss beyond that provided by TXA alone. Moreover, the use of TXA without a tourniquet led to improved early clinical outcomes such as reduced post-operative swelling, improved knee range of motion at discharge, and enhanced patient satisfaction. As medicine is practiced in an increasingly value-driven environment, this study provides a useful method for evaluating the utility of commonly used interventions. Its findings highlight the need for future investigations into the optimal administration of TXA in total knee arthroplasty.     

Determination of Tedizolid susceptibility interpretive criteria for gram-positive pathogens according to clinical and laboratory standards institute guidelines

For effective antibacterial therapy, physicians require qualitative test results using susceptibility breakpoints provided by clinical microbiology laboratories. This article summarizes the key components used to establish the Clinical Laboratory Standards Institute (CLSI) breakpoints for tedizolid. First, in vitro studies using recent surveillance and clinical trial isolates ascertained minimal inhibitory concentration (MIC) distributions against pertinent organisms, including staphylococci, streptococci, and enterococci. Studies in animal models of infection determined rates of antibacterial efficacy and survival following administration of tedizolid phosphate at doses equivalent to those in humans. Pharmacokinetic and pharmacodynamic analyses examined the relationship between plasma concentrations and MICs against the target organism. Finally, clinical trials assessed clinical and microbiologic outcomes by MIC. All these data were evaluated and combined to obtain the ratified CLSI susceptibility criteria for tedizolid of ≤0.5 μg/mL for Staphylococcus aureus, Streptococcus pyogenes, Streptococcus agalactiae, and Enterococcus faecalis and ≤0.25 μg/mL for Streptococcus anginosus group.