Treatment of Head and Neck Injuries in the Helmeted Athlete

Sport-related concussion treatment includes three major phases: initial evaluation at the time of the injury, treatment while the patient is symptomatic, and evaluation of the readiness for a gradual return to participation. Each concussion evaluation should include similar elements: assessment of symptoms, assessment of cognitive ability, assessment of coordination (of the eyes, upper extremities, and lower extremities), and assessment for additional injuries. The spine-boarding recommendations from the American College of Emergency Physicians, National Association of EMS Physicians, and National Athletic Trainers' Association have changed. These recommendations include both decreased use of spinal immobilization and removal of the helmet and shoulder pads prior to securing the athlete to the board when sufficient numbers of trained providers are present. Preseason training and pregame meetings or "medical time outs" should become standard practice for the sidelines medical team (including the athletic trainer, team physician, emergency response personnel, and possibly others).

The Basic Biology of BACE1: A Key Therapeutic Target for Alzheimer's Disease

Alzheimer’s disease (AD) is an intractable, neurodegenerative disease that appears to be brought about by both genetic and non-genetic factors. The neuropathology associated with AD is complex, although amyloid plaques composed of the β-amyloid peptide (Aβ) are hallmark neuropathological lesions of AD brain. Indeed, Aβ plays an early and central role in this disease. β-site amyloid precursor protein (APP) cleaving enzyme 1 (BACE1) is the initiating enzyme in Aβ genesis and BACE1 levels are elevated under a variety of conditions. Given the strong correlation between Aβ and AD, and the elevation of BACE1 in this disease, this enzyme is a prime drug target for inhibiting Aβ production in AD. However, nine years on from the initial identification of BACE1, and despite intense research, a number of key questions regarding BACE1 remain unanswered. Indeed, drug discovery and development for AD continues to be challenging. While current AD therapies temporarily slow cognitive decline, treatments that address the underlying pathologic mechanisms of AD are completely lacking. Here we review the basic biology of BACE1. We pay special attention to recent research that has provided some answers to questions such as those involving the identification of novel BACE1 substrates, the potential causes of BACE1 elevation and the putative function of BACE1 in health and disease. Our increasing understanding of BACE1 biology should aid the development of compounds that interfere with BACE1 expression and activity and may lead to the generation of novel therapeutics for AD.

A new symptom-based questionnaire for predicting the presence of asthma

BACKGROUND

Early diagnosis and treatment of asthma is important for improving health and minimizing the social and economic burden of the disease. A simple questionnaire would provide a convenient and timesaving tool to help physicians diagnose asthma.

OBJECTIVE

The senior author developed a simple, pre-interview screening questionnaire--the Asthma Screening Questionnaire (ASQ)--consisting of 6 questions. The present report provides performance evidence that the ASQ is a reliable instrument for diagnosing asthma in adults.

METHODS

Participants were asthmatics or controls, aged 18 to 65 years. All participants completed the questionnaire (self-administered and physician-administered), and underwent spirometry and a methacholine challenge test (if there was no reversibility during initial spirometry). Sensitivity, specificity, and positive and negative predictive values were calculated for each question, and the total scores of asthmatics were compared with those of controls. The degree of agreement between the self-administered and the physician-administered questionnaire was calculated.

RESULTS

The main symptoms discriminating asthmatics from controls were cough more than average (88% vs 0%), cough from chest (72% vs 0%), shortness of breath with exercise (84% vs 16%), and chest tightness when lying down (72% vs 4%). A cutoff point of total score > or = 4 was associated with the highest combination of sensitivity (96%) and specificity (100%). Substantial agreement was observed between the self-administered and the physician-administered questionnaire (kappa statistic, 0.56-1.00; P<.0001).

CONCLUSIONS

The ASQ is a simple, inexpensive, and efficient pre-interview screening tool to diagnose asthma.

Screening for catastrophic neck injuries in sports

The cervical spine is prone to injury due to the structure of the articulating vertebrae at the level of C4-C6, where the spinal cord occupies more of the spinal canal. Cervical spine injuries can occur in all sports and all ages. Participation in contact sports certainly increases the possibility of cervical spine injuries. In screening for catastrophic neck injuries it is vital to examine incidence and injury surveillance statistics in sports. These data can help determine sport-specific preponderance of catastrophic injury. Screening methods for predisposition to catastrophic cervical spine injuries include a concise history, physical examination, and radiographic methods. There is currently no universal classification system utilizing imaging of the cervical spine that has been validated as a screening method for catastrophic neck injuries.

Noninvasive monitoring of elevated intramuscular pressure in a model compartment syndrome via quantitative fascial motion

Compartment syndromes, conditions of elevated intramuscular pressure (IMP) resulting from trauma or chronic overuse, frequently require invasive IMP monitoring for accurate diagnosis. Our objective was to test a noninvasive ultrasound technique for estimating IMP based on fascial displacement waveforms from arterial blood pressure pulses. IMP was increased in the legs of 23 healthy adult subjects up to 80 mmHg using two blood pressure cuffs covering the region from the knee to the ankle. Receiver operator characteristic curves and recursive partitioning were used to determine the sensitivity and specificity of diagnosing elevated IMP using fascial displacement. For one curve, in which several ultrasonic measurement parameters were used along with subject body mass index and blood pressure, the sensitivity and specificity for diagnosing normal IMP (below 30 mmHg) from elevated IMP (30 mmHg and up) was 0.61 and 0.94, respectively. Recursive partitioning, in which IMP was divided into three ranges (normal <30 mmHg, midrange of 30-40 mmHg, and elevated >or=50 mmHg), resulted in improved diagnostic sensitivity (0.77) with almost no change in specificity (0.93).

Primary gastrointestinal lymphangiectasia presenting as cryptococcal meningitis

BACKGROUND

Opportunistic infections commonly occur in immunocompromised patients; however, it is unusual for an adult to present with a combined cellular and humoral immunodeficiency. Cryptococcal meningitis is a fatal condition if untreated and is usually found in patients with cellular immunodeficiency.

OBJECTIVE

To report the case of an adult patient with cryptococcal meningitis secondary to intestinal lymphangiectasia.

METHODS

A 59-year-old man was admitted to the hospital for disseminated cryptococcal meningitis and osteomyelitis. Laboratory evaluation, computed tomography, esophagogastroduodenoscopy, and biopsy were performed.

RESULTS

Laboratory evaluation revealed a lymphopenia, hypoalbuminemia, hypogammaglobulinemia, and negative human immunodeficiency virus test results by enzyme-linked immunosorbent assay and polymerase chain reaction. The complete blood cell count, urinalysis, serum and urine protein electrophoresis, and functional antibody responses to protein and polysaccharide antigens were normal. Results of computed tomography of the chest, abdomen, and pelvis were unremarkable. Multiple lymphangiectasias were visualized with esophagogastroduodenoscopy and confirmed by biopsy. The patient was treated with intravenous amphotericin B and flucytosine, and the meningitis resolved.

CONCLUSIONS

Based on a computerized search of the medical literature, this is the first description of cryptococcal meningitis secondary to intestinal lymphangiectasias. The combination of lymphopenia, hypogammaglobulinemia, and hypoalbuminemia should alert the clinician to the possibility of intestinal lymphangiectasias and the potential for immune dysfunction.

Isoprenoids and Alzheimer's disease: a complex relationship

Cholesterol metabolism has been linked to Alzheimer's disease (AD) neuropathology, which is characterized by amyloid plaques, neurofibrillary tangles and neuroinflammation. Indeed, the use of statins, which inhibit cholesterol and isoprenoid biosynthesis, as potential AD therapeutics is under investigation. Whether statins offer benefit for AD will be determined by the outcome of large, placebo-controlled, randomized clinical trials. However, their use as pharmacological tools has delineated novel roles for isoprenoids in AD. Protein isoprenylation regulates multiple cellular and molecular events and here we review the complex roles of isoprenoids in AD-relevant processes and carefully evaluate isoprenoid pathways as potential AD therapeutic targets.

Expression of somatostatin receptor types 1-5 in 81 cases of gastrointestinal and pancreatic endocrine tumors. A correlative immunohistochemical and reverse-transcriptase polymerase chain reaction analysis

Somatostatin receptors (SSTRs) have been extensively mapped in human tumors by means of autoradiography, reverse-transcriptase polymerase chain reaction (RT-PCR), in situ hybridization (ISH) and immunohistochemistry (IHC). We analyzed the SSTR type 1-5 expression by means of RT-PCR and/or IHC in a series of 81 functioning and non-functioning gastroenteropancreatic (GEP) endocrine tumors and related normal tissues. Moreover, we compared the results with clinical, pathological and hormonal features. Forty-six cases (13 intestinal and 33 pancreatic) were studied for SSTR 1-5 expression using RT-PCR, IHC with antibodies to SSTR types 2, 3, 5 and ISH for SSTR2 mRNA. The vast majority of tumors expressed SSTR types 1, 2, 3 and 5, while SSTR4 was detected in a small minority. Due to the good correlation between RT-PCR and IHC data on SSTR types 2, 3, and 5, thirty-five additional GEP endocrine tumors were studied with IHC alone. Pancreatic insulinomas had an heterogeneous SSTR expression, while 100% of somatostatinomas expressed SSTR5 and 100% gastrinomas and glucagonomas expressed SSTR2. Pre-operative biopsy material showed an overlapping immunoreactivity with that of surgical specimens, suggesting that the SSTR status can be detected in the diagnostic work-up. It is concluded that SSTRs 1-5 are heterogeneously expressed in GEP endocrine tumors and that IHC is a reliable tool to detect SSTR types 2, 3 and 5 in surgical and biopsy specimens.

Titrating the expression of a Gi protein-coupled receptor using an ecdysone-inducible system in CHO-K1 cells

Changes in receptor density are often associated with pathological conditions. For example, high levels of the G protein-coupled somatostatin receptor, sst2, have been detected in a number of malignant cell types, a characteristic feature that is routinely utilised as a diagnostic tool. However, how the increased receptor expression affects cellular function through alterations in G protein-coupling or changes in the intensity or duration of activated signalling pathways is poorly understood. The current report details the use of an ecdysone-inducible expression system in CHO-K1 cells, whereby the consequence of modulating the level of human sst2 receptor expression on specific transduction events can be examined. A time- and concentration-dependent induction of sst2 receptor expression was attained by exposure of cells to the ecdysteroid-inducing agent, muristerone A (MuA). Increases in sst2 receptor expression were determined by immunoassay, immunoblotting and immunocytochemical analysis. Maximal sst2 receptor expression was obtained after treatment of cells with 7 microM MuA for 24 h. Functionality of the sst2 receptor was assessed by immunoblot analysis of phosphorylated forms of MAP kinase. Following receptor activation, time-dependent increases in the level of MAP kinase phosphorylation were shown to correlate with the degree of sst2 receptor induction. Confirmation of receptor activation was determined by visualisation of ligand-induced redistribution of sst2 receptors from the plasma membrane to discrete intracellular compartments. However, in a series of further studies, both immunocytochemical and fluorescence-activated cell sorting (FACS) analyses demonstrated that over a prolonged period, stable receptor expression could not be maintained in CHO-K1 cells using this expression system. Thus, routine analysis of the sst2 receptor expressing cell population is required to derive comparable results between assays, especially when some assays provide information from the whole cell population whilst others are based at the single cell level. On the basis of these observations we conclude that, providing such quality control measurements are taken, the ecdysone inducible expression system is a useful tool to modulate functional sst2 receptor expression in an in vitro environment over short time periods.

Characterisation of somatostatin sst2 receptor splice variants

Somatostatin is a peptide with a multitude of functions in the central nervous system and the periphery. It mediates its actions by binding to high-affinity G-protein coupled receptors, genes for five of which (sst1-sst5) have recently been cloned. The somatostatin sst2 receptor exists as two splice variants, sst2(a) and sst2(b) receptors, which differ in length and composition of their intracellular carboxy-termini. In this review, we describe the localisation of the two receptor isoforms in the central nervous system, the periphery and also in tumour tissue. Furthermore, we summarise and discuss the data on the functional properties of the recombinant splice variants that have been generated so far, which include activation of extracellular acidification rates, inhibition of adenylate cyclase and activation of MAP-kinases as well as the transcription factor Elk-1.

A unique talin homologue with a villin headpiece-like domain is required for multicellular morphogenesis in Dictyostelium

Molecules involved in the interaction between the extracellular matrix, cell membrane and cytoskeleton are of central importance in morphogenesis. Talin is a large cytoskeletal protein with a modular structure consisting of an amino-terminal membrane-interacting domain, with sequence similarities to members of the band 4.1 family, and a carboxy-terminal region containing F-actin-binding and vinculin-binding domains [1] [2]. It also interacts with the cytoplasmic tail of beta integrins which, on the external face of the membrane, bind to extracellular matrix proteins [3]. The possible roles of talin in multicellular morphogenesis in development remain largely unexplored. In Dictyostelium, a eukaryotic microorganism capable of multicellular morphogenesis, a talin homologue (TALA) has previously been identified and shown to play an important role in cell-to-substrate adhesion and maintenance of normal elastic properties of the cell [4] [5] [6]. Here, we describe a second talin homologue (TALB) that is required for multicellular morphogenesis in the development of Dictyostelium. Unlike any other talin characterised to date, it contains an additional carboxy-terminal domain homologous to the villin headpiece.

A unique rat model of bile ductular hyperplasia in which liver is almost totally replaced with well-differentiated bile ductules

A novel rat model was developed in which furan combined in a unique synergistic manner with bile duct ligation to induce replacement of most of liver with well-differentiated hyperplastic bile ductules. Multiple tissue sections of liver from Fischer 344 male rats first subjected to a bile duct ligation and 1 week later given furan by gavage at 45 mg/kg body weight, once a day, five times weekly for 5 to 6 weeks, exhibited a mean percent of bile ductule tissue per total liver section area of 72.6 +/- 16.3% compared to control values of 20.0 +/- 4.2% for bile duct-ligated rats that received corn oil by gavage instead of furan and 11.9 +/- 3.1% for rats that were given a sham operation followed by furan. This dramatic difference was also reflected by the very high mean gamma-glutamyl transpeptidase specific activity of liver homogenates from the bile duct-ligated/furan-treated rats, which was approximately 8 x 10(3) nmoles p-nitroaniline/mg protein/hour versus values of approximately 2 x 10(3) for bile duct-ligated/corn oil control, approximately 1 x 10(3) for sham-operated/furan-treated control, and 44.9 for untreated rat. The data presented support a potentially powerful experimental model for investigating bile ductular cell functions, differentiation, and proliferation.

A human respiratory syncytial virus (RSV) primate model of enhanced pulmonary pathology induced with a formalin-inactivated RSV vaccine but not a recombinant FG subunit vaccine

Human respiratory syncytial virus (RSV) is the leading cause of severe bronchiolitis and pneumonia in infants. RSV vaccine development has been stifled for the past 23 years because infants vaccinated with formalin-inactivated (FI) RSV have experienced exacerbated disease upon RSV infection. This exacerbated disease phenomenon is poorly understood, in part because of the lack of a primate model that exhibits a similar exacerbated disease state. Vaccination of African green monkeys with either FI RSV or a genetically engineered subunit vaccine termed FG glycoprotein reduced replication of challenge virus. However, only vaccination with FI RSV induced an enhanced pulmonary pathologic response to RSV infection. Pulmonary inflammatory scores in the FG glycoprotein-vaccinated monkeys were no greater than in monkeys vaccinated with adjuvant alone. This is the first demonstration of RSV vaccine-induced enhanced pathology in a primate and illustrates that a subunit vaccine has the potential of circumventing this exacerbated disease phenomenon.

Dress for success. A nurse's knowledge of simple clothing adaptations and dressing aids may make the difference between rehabilitation success and failure

Typical chronic diseases that affect older people often result in the loss of independence in daily activities, such as dressing. Losses of functional independence in such basic areas are factors in the institutionalization of elderly persons. The nurse's challenge? Help your clients remain independent. Simple clothing adaptations and dressing aids will help elderly people preserve self-esteem, social contacts, and control of their personal environment.

Vaccination of cotton rats with a chimeric FG glycoprotein of human respiratory syncytial virus induces minimal pulmonary pathology on challenge

The cotton rat model of human respiratory syncytial virus (RSV) infection was used to study the safety and efficacy of a chimeric FG glycoprotein that was expressed in insect cells using a baculovirus vector. Histologic and virologic examination of vaccinated rat lungs was done after challenge with RSV. When rats were challenged 1 month after vaccination, severe pulmonary inflammation characterized by both a mononuclear and polymorphonuclear cell infiltrate and 30%-40% involvement of lung tissue was observed with a formalin-inactivated RSV vaccine. The FG glycoprotein induced minimal lung inflammation (involving 2%-5% of the lung), while negative controls had 1%-3% lung involvement. Two doses with as little as 20 ng of FG glycoprotein formulated in an aluminum hydroxide adjuvant completely protected the cotton rats from RSV challenge. Thus the chimeric FG glycoprotein is highly immunogenic and induces minimal pulmonary inflammation in the cotton rat model.

Precipitation of the renin inhibitor ditekiren upon i.v. infusion; in vitro studies and their relationship to in vivo precipitation in the cynomolgus monkey

Ditekiren is a pseudo-octapeptide being developed as an inhibitor of human renin. Preclinical drug safety studies with this drug involved continuous i.v. infusions through indwelling catheters in the right internal jugular vein of the cynomolgus monkey for up to 30 days. The following physiocochemical properties of ditekiren make it susceptible to intravascular precipitation immediately following iv infusion: (1) the water solubility of ditekiren is high at acidic pH where the drug is formulated (pH 4) but low at physiologic pH, and (2) the water solubility of ditekiren decreases by roughly 50% from room temperature (25 degrees C) to physiologic temperature (37 degrees C). Studies of 28- and 30-day infusion durations revealed intravascular precipitation in monkeys using drug solutions and rates of infusion that were expected to be precipitation-free, based on the solubility of ditekiren and assumptions about blood flow in the monkey right internal jugular vein. Therefore, an in vitro apparatus was used to study the relationship among the drug concentration in the infusate, the rate of infusion, and the occurrence of precipitation in a fluid stream of phosphate-buffered bovine serum albumin solution (a facsimile of plasma). Maximum rates of infusion without precipitation were determined for a range of concentrations of drug in two separate formulations. Infusion conditions identified by the in vitro method as precipitation-free were then tried in a definitive 14-day monkey study. Of 24 monkeys infused with solutions of ditekiren, none showed evidence of intravascular precipitation.(ABSTRACT TRUNCATED AT 250 WORDS)