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Purpose: Use of spinal cord monitoring in children with cerebral palsy (CP) and neuromuscular scoliosis is challenging. The previous reports suggest low success rates in the setting of CP, and it is unclear if transcranial electric motor evoked potentials (TcMEP) monitoring is contraindicated in patients with an active seizure disorder. The purpose of this study was to determine (1) are patients with CP able to be appropriately monitored with TcMEP? and (2) does TcMEP cause an increase in seizure activity? Methods: This was an institutional review board-approved retrospective cohort study observing 304 patients from 2011 to 2020. Inclusion criteria included all patients with CP undergoing posterior spinal fusion during this time. Intraoperative data were examined for the ability to obtain monitoring and any intraoperative events. Patients were followed for 3 months postoperatively to determine any increase in seizure activity that could have been attributed to the TcMEP monitoring. Results: Of the 304 patients who were observed, 21% (20.8%) were unable to be monitored due to lacking baseline signals from the extremities. Seventy-seven percent (77.5%) were successfully monitored with TcMEP. For these patients, no increased seizure activity was documented either intra- or postoperatively. Conclusion: A high percentage of children (77.5%) with CP were able to be successfully monitored with TcMEP during posterior spinal fusion. Furthermore, the concerns about increased seizure activity after TcMEP were not supported by the data from this cohort. Technical details of successful neuromonitoring in these patients are important and included increased stimulation voltage requirements and latency times. Level of evidence: III retrospective comparative study.

Mt Sinai breast oncology partook in Oncology Care Model while converting our chemo consent into an electronic version

Achondroplasia, the most common skeletal dysplasia, is characterized by a variety of medical, functional and psychosocial challenges across the lifespan. The condition is caused by a common, recurring, gain-of-function mutation in FGFR3, the gene that encodes fibroblast growth factor receptor 3. This mutation leads to impaired endochondral ossification of the human skeleton. The clinical and radiographic hallmarks of achondroplasia make accurate diagnosis possible in most patients. However, marked variability exists in the clinical care pathways and protocols practised by clinicians who manage children and adults with this condition. A group of 55 international experts from 16 countries and 5 continents have developed consensus statements and recommendations that aim to capture the key challenges and optimal management of achondroplasia across each major life stage and sub-specialty area, using a modified Delphi process. The primary purpose of this first International Consensus Statement is to facilitate the improvement and standardization of care for children and adults with achondroplasia worldwide in order to optimize their clinical outcomes and quality of life.

Wetlands are important carbon (C) sinks, yet many have been destroyed and converted to other uses over the past few centuries, including industrial salt making. A renewed focus on wetland ecosystem services (e.g., flood control, and habitat) has resulted in numerous restoration efforts whose effect on microbial communities is largely unexplored. We investigated the impact of restoration on microbial community composition, metabolic functional potential, and methane flux by analyzing sediment cores from two unrestored former industrial salt ponds, a restored former industrial salt pond, and a reference wetland. We observed elevated methane emissions from unrestored salt ponds compared to the restored and reference wetlands, which was positively correlated with salinity and sulfate across all samples. 16S rRNA gene amplicon and shotgun metagenomic data revealed that the restored salt pond harbored communities more phylogenetically and functionally similar to the reference wetland than to unrestored ponds. Archaeal methanogenesis genes were positively correlated with methane flux, as were genes encoding enzymes for bacterial methylphosphonate degradation, suggesting methane is generated both from bacterial methylphosphonate degradation and archaeal methanogenesis in these sites. These observations demonstrate that restoration effectively converted industrial salt pond microbial communities back to compositions more similar to reference wetlands and lowered salinities, sulfate concentrations, and methane emissions.

Children with skeletal dysplasia present unique challenges for safe anesthetic care including differences in the anatomy of the respiratory system, possibility of cervical spine instability or spinal stenosis, and a unique body habitus. Even seemly routine anesthesia can result in respiratory arrest or spinal cord injury. These complications can largely be avoided by proper planning such as appropriate techniques for the intubation of difficult airways, recognition of cervical instability, neuromonitoring for any anesthesia over an hour in patients with severe spinal stenosis, and preoperative assessment of the trachea and avoidance of neuraxial anesthesia in children with Morquio syndrome.

Responsive neurostimulation (RNS) is an emerging therapy for patients with refractory focal epilepsy who are not candidates for surgical resection, with limited published experience in the pediatric population. We report a case of refractory multifocal epilepsy following febrile infection related epilepsy syndrome (FIRES) in which surgical resection was not feasible due to multifocal independent seizures and risk of cognitive deficit, and RNS was pursued. Relevant RNS data and neuropsychological testing results were reviewed. By eight months after implantation, decreased frequency and severity of clinical seizures were noted, and RNS data revealed decreased “long episodes,” reduced spread of electrographic seizures, and fewer detections. Neuropsychological assessment, though potentially confounded by stimulant medication, revealed significant improvement in multiple cognitive domains, particularly working memory and processing speed, at six months. These findings illustrate success in detecting and aborting seizures, and additionally suggest a neuromodulatory effect of RNS stimulation. Our case demonstrates feasibility, efficacy and safety of RNS in a pediatric patient with FIRES, with evidence to also suggest cognitive improvement.

Demand for women’s health services is increasing. With the declining number of women’s health care nurse practitioners, it is important that primary care nurse practitioners be prepared to meet the need for women’s health care. An elective course in women’s health was created to increase women’s health content in a primary care graduate nurse practitioner program. This article describes the development of the course and the use of story-based learning as 1 of the teaching strategies. Positive student feedback about the use of stories in the course showed the effectiveness of this teaching strategy.

The severe acute respiratory syndrome coronavirus 2 (coronavirus disease 2019 [COVID-19]) pandemic has challenged medical systems and clinicians globally to unforeseen levels. Rapid spread of COVID-19 has forced clinicians to care for patients with a highly contagious disease without evidence-based guidelines. Using a virtual modified nominal group technique, the Pediatric Difficult Intubation Collaborative (PeDI-C), which currently includes 35 hospitals from 6 countries, generated consensus guidelines on airway management in pediatric anesthesia based on expert opinion and early data about the disease. PeDI-C identified overarching goals during care, including minimizing aerosolized respiratory secretions, minimizing the number of clinicians in contact with a patient, and recognizing that undiagnosed asymptomatic patients may shed the virus and infect health care workers. Recommendations include administering anxiolytic medications, intravenous anesthetic inductions, tracheal intubation using video laryngoscopes and cuffed tracheal tubes, use of in-line suction catheters, and modifying workflow to recover patients from anesthesia in the operating room. Importantly, PeDI-C recommends that anesthesiologists consider using appropriate personal protective equipment when performing aerosol-generating medical procedures in asymptomatic children, in addition to known or suspected children with COVID-19. Airway procedures should be done in negative pressure rooms when available. Adequate time should be allowed for operating room cleaning and air filtration between surgical cases. Research using rigorous study designs is urgently needed to inform safe practices during the COVID-19 pandemic. Until further information is available, PeDI-C advises that clinicians consider these guidelines to enhance the safety of health care workers during airway management when performing aerosol-generating medical procedures. These guidelines have been endorsed by the Society for Pediatric Anesthesia and the Canadian Pediatric Anesthesia Society.

Making high‐quality dopamine (DA)‐producing cells for basic biological or small molecule screening studies is critical for the development of novel therapeutics for disorders of the ventral midbrain. Currently, many ventral midbrain assays have low signal‐to‐noise ratio due to low levels of cellular DA and the rate‐limiting enzyme of DA synthesis, tyrosine hydroxylase (TH), hampering discovery efforts. Using intensively characterized ventral midbrain cells derived from human skin, which demonstrate calcium pacemaking activity and classical electrophysiological properties, we show that an L‐type calcium agonist can significantly increase TH protein levels and DA content and release. Live calcium imaging suggests that it is the immediate influx of calcium occurring simultaneously in all cells that drives this effect. Genome‐wide expression profiling suggests that L‐type calcium channel stimulation has a significant effect on specific genes related to DA synthesis and affects expression of L‐type calcium receptor subunits from the CACNA1 and CACNA2D families. Together, our findings provide an advance in the ability to increase DA and TH levels to improve the accuracy of disease modeling and small molecule screening for disorders of the ventral midbrain, including Parkinson's disease. Using intensively characterized ventral midbrain cells derived from humans, we show that an L‐type calcium agonist can significantly increase tyrosine hydroxylase protein levels and dopamine release. Genome‐wide expression profiling suggests that L‐type calcium channel stimulation has a significant effect on specific genes related to dopamine synthesis and affects expression of L‐type calcium receptor subunits from the CACNA1 and CACNA2D families.

Alkenone‐derived paleotemperature reconstruction holds great promise in lake environments. However, the occurrence of multiple species of alkenone‐producing haptophyte algae in a single lake can complicate the translation of alkenone unsaturation to temperature if each species requires an individual temperature calibration. Here, we present the first systematic monitoring of two alkenone‐producing haptophytes throughout the course of a seasonal cycle in Lake George, North Dakota, using a combined approach of DNA sequencing and alkenone lipid characterization. Field sampling revealed a nonoverlapping haptophyte succession, with both an early and late season haptophyte bloom event. Culturing experiments demonstrated that the two haptophyte species responsible for these blooms had statistically similar alkenone‐temperature responses, although the culture‐based calibrations were distinct from the in situ calibration. Bloom timing of each haptophyte species corresponded to surface‐water temperatures that differed by more than 10°C, revealing that changes in bloom intensities for each species will skew the sediment‐inferred temperatures to a different stage of the growth season. These results highlight the importance of accounting for bloom timing when interpreting alkenone‐derived temperatures in sediment cores, especially in lakes that experience large seasonal fluctuations in water column temperature and salinity.

At a recent consensus conference, the Malignant Hyperthermia Association of the United States addressed 6 important and unresolved clinical questions concerning the optimal management of patients with malignant hyperthermia (MH) susceptibility or acute MH. They include: (1) How much dantrolene should be available in facilities where volatile agents are not available or administered, and succinylcholine is only stocked on site for emergency purposes? (2) What defines masseter muscle rigidity? What is its relationship to MH, and how should it be managed when it occurs? (3) What is the relationship between MH susceptibility and heat- or exercise-related rhabdomyolysis? (4) What evidence-based interventions should be recommended to alleviate hyperthermia associated with MH? (5) After treatment of acute MH, how much dantrolene should be administered and for how long? What criteria should be used to determine stopping treatment with dantrolene? (6) Can patients with a suspected personal or family history of MH be safely anesthetized before diagnostic testing? This report describes the consensus process and the outcomes for each of the foregoing unanswered clinical questions.

Both subjective cognitive decline (SCD) and a family history of Alzheimer’s disease (AD) portend risk of brain abnormalities and progression to dementia. Posterior default mode network (pDMN) connectivity is altered early in the course of AD. It is unclear whether SCD predicts similar outcomes in cognitively normal individuals with a family history of AD.

Background: Vorapaxar is a first-in-class protease-activated receptor-1 antagonist indicated for the reduction of cardiovascular death, myocardial infarction, and stroke in stable patients with prior atherothrombosis, who have not had a prior stroke or transient ischemic attack. The aims of this study were to investigate: 1) the role of vorapaxar in patients with severe coronary artery disease treated previously with coronary artery bypass grafting (CABG); and 2) safety in patients undergoing CABG while receiving vorapaxar.Methods: TRA 2°P-TIMI 50 was a randomized, double-blinded, placebo-controlled trial of vorapaxar in 26,449 stable patients with prior atherothrombosis followed for a median of 30 months. We 1) investigated the efficacy of vorapaxar among patients with a history of CABG prior to randomization (n=2942); and 2) assessed the safety among 367 patients who underwent a new CABG during the trial.Results: Patients with a prior CABG were at higher risk for cardiovascular death, myocardial infarction, or stroke at three years compared with patients without a prior CABG (13.7% vs. 7.8%, p<0.001). Among patients with a prior CABG, vorapaxar significantly reduced the risk of cardiovascular death, myocardial infarction, or stroke (11.9% vs. 15.6%, hazard ratio 0.71, 95% confidence interval 0.58–0.88, p=0.001; number-needed-to-treat = 27). In patients undergoing CABG while receiving vorapaxar, the rate of Thrombolysis in Myocardial Infarction CABG major bleeding was 6.3% vs. 4.1% with placebo (hazard ratio 1.53, 95% confidence interval 0.58–4.01, p=0.39).Conclusions: In patients with a prior CABG, vorapaxar significantly reduced the risk of recurrent major cardiovascular events. In patients undergoing CABG while receiving vorapaxar, bleeding risk appeared similar to that seen in the overall trial population.

IMPORTANCE: In the PEGASUS-TIMI 54 trial, treatment with ticagrelor reduced the incidence of cardiovascular death, myocardial infarction, or stroke by 15% to 16% among stable patients compared with placebo. However, more patients prematurely discontinued treatment with ticagrelor than with placebo. OBJECTIVE: To investigate the reasons and timing of discontinuation of treatment with ticagrelor among stable patients prior myocardial infarction. DESIGN, SETTING, AND PARTICIPANTS: In the PEGASUS-TIMI 54 trial, 21 162 stable outpatients with prior myocardial infarction were randomly assigned to 90 mg of ticagrelor twice daily, 60 mg of ticagrelor twice daily, or placebo, with all of the patients receiving a low dose of aspirin. These participants were followed up for a median of 33 months (study start date: October 2010; completion date: December 2014). Discontinuation of treatment was evaluated by treatment arm, cause, and timing. This analysis was initiated in May 2015. MAIN OUTCOME AND MEASURE: Discontinuation of treatment. RESULTS: Over 33 months, 32%, 29%, and 21% of patients receiving 90 mg of ticagrelor, 60 mg of ticagrelor, and placebo, respectively, discontinued treatment (P &lt; .001). Discontinuation of treatment due to an adverse event occurred in 19%, 16%, and 9% of patients, respectively (P &lt; .001). The most frequent adverse events leading to discontinuation of treatment were bleeding (with Kaplan-Meier event rates of 7.8%, 6.2%, and 1.5% of patients, respectively; P &lt; .001) and dyspnea (6.5%, 4.6%, and 0.8% of patients, respectively; P &lt; .001). Eighty-six percent of bleeding events that led to the discontinuation of treatment with ticagrelor were nonmajor, and 86% of adverse events due to dyspnea that led to discontinuation of treatment with ticagrelor were mild or moderate in severity. The discontinuation rates are annualized for patients who received 90 mg of ticagrelor twice daily (hazard ratio [HR], 2.00 [95% CI, 1.84-2.16] for the first year; HR, 1.12 [95% CI, 1.00-1.26] for the second and third years) and patients who received 60 mg of ticagrelor twice daily (HR, 1.59 [95% CI, 1.46-1.73] for the first year; HR, 1.18 [95% CI, 1.06-1.32] for the second and third years) compared with patients who received placebo. CONCLUSIONS AND RELEVANCE: When initiated among stable patients with prior myocardial infarction, discontinuation of treatment with ticagrelor was driven primarily by nonserious adverse events occurring primarily early after randomization. For patients completing 1 year of treatment, the subsequent discontinuation rate was low. These data demonstrate how adverse events considered “nonserious” by traditional trial criteria may have an effect on quality of life and, thus, may precipitate the discontinuation of treatments and underscore the need for patient education and counseling on the timing and nature of adverse effects with the aim of improving adherence when appropriate. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01225562

•Extreme delta brush pattern was noted in a novel form of autoimmune meningoencephalomyelitis.•Characteristic MRI findings suggest autoimmune GFAP astrocytopathy.•Autoimmune GFAP astrocytopathy was not steroid-responsive in a pediatric patient.

Purpose: We describe an instance in which complete paraplegia was evident immediately postoperatively after apparently uneventful lumbar epidural-general anesthesia in a patient with Morquio Type A syndrome (Morquio A) with moderate thoracic spinal stenosis. Clinical features: A 16-yr-old male with Morquio A received lumbar epidural-general anesthesia for bilateral distal femoral osteotomies. Preoperative imaging had revealed a stable cervical spine and moderate thoracic spinal stenosis with a mild degree of spinal cord compression. Systolic blood pressure (BP) was maintained within 20% of the pre-anesthetic baseline value. The patient sustained a severe thoracic spinal cord infarction. The epidural anesthetic contributed to considerable delay in the recognition of the diagnosis of paraplegia. Conclusion: This experience leads us to suggest that, in patients with Morquio A, it may be prudent to avoid the use of epidural anesthesia without very firm indication, to support BP at or near baseline levels in the presence of even moderate spinal stenosis, and to avoid flexion or extension of the spinal column in intraoperative positioning. If the spinal cord/column status is unknown or if the patient is known to have any degree of spinal stenosis, we suggest that the same rigorous BP support practices that are typically applied in other patients with severe spinal stenosis, especially stenosis with myelomalacia, should apply to patients with Morquio A and that spinal cord neurophysiological monitoring should be employed. In the event that cord imaging is not available, e.g., emergency procedures, it would be prudent to assume the presence of spinal stenosis.

IMPORTANCE: Myringotomy and tympanostomy tube placement for chronic otitis media with effusion is the most common reason for a child to undergo anesthesia in the United States. Postoperative tube obstruction occurs in 1.4% to 36.0% of cases and remains a challenge in achieving middle ear ventilation. OBJECTIVE: To identify risk factors associated with tube obstruction. DESIGN, SETTING, AND PARTICIPANTS: Retrospective medical record review of 248 patients, mean age 2.54 years, seen between March 2007 and June 2011 in a tertiary care pediatric hospital. INTERVENTIONS: Tympanostomy tube placement and postoperative otic drop therapy. MAIN OUTCOMES AND MEASURES: Tube patency at postoperative visit, number of tube removals and revisions, age, sex, body mass index (BMI), middle ear fluid type at time of surgery, and time between surgery and first postoperative visit were examined. Type of surgery (tympanostomy tube placement alone, adenoidectomy + tympanostomy tube placement, tympanostomy tube placement + adenoidectomy + tonsillectomy) and its effect on tube patency were also reviewed. RESULTS: At first follow-up, 10.6% of patients had occlusion of one or both tubes. No significant association was found between tube patency and a patient’s BMI percentile, sex, or procedure type. Patients with no middle ear fluid were more likely to have patent tubes than those who had serous fluid (odds ratio [OR], 3.5; 95% CI, 1.2-10.6; P = .02). A significant inverse correlation was found between patency and time between surgery and follow-up in that patients who had longer follow-up after surgery were less likely to have patent tubes (OR per day of follow-up delay, 0.990; 95% CI, 0.981-0.999; P = .01). CONCLUSIONS AND RELEVANCE: Tympanostomy tube obstruction was seen in 10.6% of patients. Serous fluid and increased time to postoperative visit were statistically significant indicators for tube occlusion.

The article offers information on the professional and personal life actor and screenwriter, Justin Theroux and mentions topics including his role in HBO's production "The Leftovers," his fiance Jennifer Aniston and presents his views on his being politically correct.

The article explores aid coming to Africa. In his book "The Great Escape: Health, Wealth and the Origins of Inequality," economist Angus Deaton questioned the role of the aid and described that the greater proportion of the world's poor are found in China and India. Novelist Charles Dickens is among those individuals known for contributing aid to Africa, along with former U.S. President Bill Clinton and Microsoft founder Bill Gates. INSET: Afrian Philantropy Done Right.

This article provides a clinical nursing update on major neurological complications associated with HIV and AIDS. Life expectancy for those with AIDS has increased as a consequence of antiretroviral therapy, and thus, neurological complications remain a clinical challenge. Four significant diseases associated with HIV and AIDS are addressed: HIV-associated dementia, peripheral neuropathy, cryptococcal meningitis, and toxoplasmosis. Updated statistics, a review of pathophysiology, common manifestations, diagnostic tests, and standard treatments are discussed for each disease. Nursing considerations when caring for this population are reviewed and include assessment, safety, activities of daily living, pain management, and treatment adherence.

Acute ST-segment elevation myocardial infarction (STEMI) accounts for approximately 30% of all acute coronary syndromes (ACS). The high early mortality for patients with STEMI is largely due to the extent of the ischemic injury. However, immediate reperfusion either pharmacologically with fibrinolysis or mechanically by primary percutaneous coronary intervention (PCI) limits the size of the infarction and reduces mortality. Reperfusion therapy by primary PCI reduces mortality and the risk of reinfarction, beyond the benefits achieved by fibrinolysis, especially when the primary PCI is initiated within 90 minutes of first medical contact. The use of adjuvant therapy with antiplatelet and anticoagulant agents is essential to enhance the results of reperfusion, and/or maintain vessel patency following either mode of reperfusion.

Despite the reduction of coronary heart disease mortality over the past 40 years, hospital admissions for acute coronary syndromes (ACS) continue to increase. The goal of this 2-part article is to review the issues at each stage of assessment and management of the ACS patient, and to propose an optimal treatment strategy for the individual patient in the context of the realities, culture, and delivery of healthcare in Canada.

The article offers information on several notable people, who suffered from gout, including founding father of the U.S., Benjamin Franklin, painter, Leonardo da Vinci, and economist, Karl Marx.

Although the Thrombolysis In Myocardial Infarction (TIMI) score incorporates ST deviation, it does not account for characteristics of the ST deviations. In the present study, it was hypothesized that the magnitude and characteristics of ST deviation may add to the prognostic values of the TIMI risk score in acute coronary syndrome (ACS) patients, particularly in lower-risk patients with a TIMI risk score of less than 5.

To evaluate the cost-effectiveness of enoxaparin versus unfractionated heparin in conjunction with fibrinolysis in ST elevation myocardial infarction patients within Canada.

Despite its widespread use, limited data on the validity of the Canadian Cardiovascular Society angina (CCSA) classification relative to other measures of functional status have been reported.

There is substantial concensus regarding the professional roles derived from theoretical models of community psychology. Community field training is necessary for graduate students to experience fundamental role characteristics and develop applied skills relevant to later community practice. A doctoral-level internship and its relationship to professional roles in community psychology is described. Problems associated with development of community internships are discussed from the perspective of both the sponsoring graduate program and the student. Given the importance of understanding Canadian issues, systems, and polices for community practice, it appears highly desirable that graduate students do their internships in Canada.

Cholesterol homeostasis is of emerging therapeutic importance for Alzheimer's disease (AD). Agonists of liver-X-receptors (LXRs) stimulate several genes that regulate cholesterol homeostasis, and synthetic LXR agonists decrease neuropathological and cognitive phenotypes in AD mouse models. The cholesterol transporter ABCG1 is LXR-responsive and highly expressed in brain. In vitro, conflicting reports exist as to whether ABCG1 promotes or impedes Aβ production. To clarify the in vivo roles of ABCG1 in Aβ metabolism and brain cholesterol homeostasis, we assessed neuropathological and cognitive outcome measures in PDAPP mice expressing excess transgenic ABCG1. A 6-fold increase in ABCG1 levels did not alter Aβ, amyloid, apolipoprotein E levels, cholesterol efflux, or cognitive performance in PDAPP mice. Furthermore, endogenous murine Aβ levels were unchanged in both ABCG1-overexpressing or ABCG1-deficient mice. These data argue against a direct role for ABCG1 in AD. However, excess ABCG1 is associated with decreased levels of sterol precursors and increased levels of SREBP-2 and HMG-CoA-reductase mRNA, whereas deficiency of ABCG1 leads to the opposite effects. Although functions for ABCG1 in cholesterol efflux and Aβ metabolism have been proposed based on results with cellular model systems, the in vivo role of this enigmatic transporter may be largely one of regulating the sterol biosynthetic pathway.

The objective of this study was to design a simple apparatus for laboratory calibration of diaphragm type earth pressure cells (EPC). A new testing device was fabricated to permit the application of normal stress to the EPC using various types of soil and load configurations. With respect to fluid pressure, the response of the EPC can be different for the simplest earth pressure conditions because of an arching effect or nonuniform contact stress. For an EPC with a rigid outer rim, sensitivities computed from soil calibrations were lower than those determined from fluid calibrations by about 20 %.

Acute pancreatitis after posterior spinal fusion in children is associated with high intraoperative blood loss. Inflammation, oxidative stress, and pancreatitis markers were assessed during this period. Five of the 17 patients studied developed acute pancreatitis 3–7 days after surgery. Intraoperative blood loss (4850±2315 vs 1322±617 ml) and peak tumor necrosis factor α levels (15.29±5.3 vs 8.27±4.6 pg/ml) in the immediate postoperative period were significantly higher in these five patients than in controls, respectively. No differences were noted in serum interleukin 8, interleukin 6, pancreatis-associated protein, or urine malondialdehyde levels. Urine trypsin-associated peptide, elevated initially in all patients, was significantly higher in the acute pancreatitis group at diagnosis. Length of stay was significantly longer in the acute pancreatitis group. Greater blood loss and peak tumor necrosis factor α are associated with subsequent risk of acute pancreatitis, suggesting a role of ischemia–reperfusion injury.

Presents the short story "Mutrux`s Confession or He Who Gets Slapped," by Alexander Theroux.

OBJECTIVES

Apolipoprotein E (apoE) is a lipid transport molecule, which has been linked to the pathogenesis of Alzheimer’s disease. Recently we have demonstrated that the oxidative insults in hippocampus from AD patients were dependent on the apoE genotype. Interestingly, apoE protein concentration in hippocampus follows a genotype-dependent gradient with the lowest level occurring in ε4 allele carrier. We raised the possibility that, in the hippocampus, the apoE level affects the oxidant/antioxidant balance. Here, we have examined in the apoE-deficient mouse the oxidant/antioxidant status in hippocampus and in frontal cortex from APOE-KO and wild-type mice at 3 and 13 months. We provided evidence that, in the hippocampus, the absence of apoE has a clear impact on the oxidant/antioxidant status. Endogenous level of thiobarbituric acid-reactive substances (TBARS) was found to be markedly elevated whereas level of α-tocopherol was decreased in APOE-deficient mice at 3 and 13 months. Superoxide dismutase activities were also lower in APOE-deficient mice at 13 months. Taken together, these data indicate that the steady state level of apoE may influence, to a certain extent, the balance between oxidants and antioxidants in hippocampus.

An earth pressure cell (EPC) is a device designed to provide an estimate of normal stress in soil. The practice of designing and manufacturing stress-measurement devices revolves around the study of the interaction between the measuring device and the host material. However, distribution of normal stress is not necessarily uniform across a given surface. Consequently, output from an EPC may be different under soil-loading conditions than under fluid pressure. In addition, depending on the design, as the cell deflects, an arching-type phenomenon may develop. A study was conducted to devise a scheme for calibration of EPCs and to recommend a procedure for field installation. A new testing device was designed to permit the application of uniaxial soil pressure to the EPC by using various types of soil and load configurations. Sensitivities computed from soil calibrations varied from those determined from fluid calibrations by as much as 30 percent. A field installation procedure was developed from model tests. In the laboratory, a thin-walled steel cylinder with a geotextile bottom was filled with uniform silica sand in a medium-dense state, and the EPC was placed within the sand. The entire apparatus (EPC, cylinder, and sand) was carried into the field and installed in the desired locations. The steel cylinder was then removed, leaving the cell, sand, and geotextile behind. Preliminary field data indicate that the soil calibration and placement procedure provide reasonably accurate measurements of the change in vertical stress.