Defibrillation before EMS arrival in western Sweden.

BACKGROUND: Bystanders play a vital role in public access defibrillation (PAD) in out-of-hospital cardiac arrest (OHCA). Dual dispatch of first responders (FR) alongside emergency medical services (EMS) can reduce time to first defibrillation. The aim of this study was to describe the use of automated external defibrillators (AEDs) in OHCAs before EMS arrival. METHODS: All OHCA cases with a shockable rhythm in which an AED was used prior to the arrival of EMS between 2008 and 2015 in western Sweden were eligible for inclusion. Data from the Swedish Register for Cardiopulmonary Resuscitation (SRCR) were used for analysis, on-site bystander and FR defibrillation were compared with EMS defibrillation in the final analysis. RESULTS: Of the reported 6675 cases, 24% suffered ventricular fibrillation (VF), 162 patients (15%) of all VF cases were defibrillated before EMS arrival, 46% with a public AED on site. The proportion of cases defibrillated before EMS arrival increased from 5% in 2008 to 20% in 2015 (p<0.001). During this period, 30-day survival increased in patients with VF from 22% to 28% (p=0.04) and was highest when an AED was used on site (68%), with a median delay of 6.5min from collapse to defibrillation. Adjusted odds ratio for on-site defibrillation versus dispatched defibrillation for 30-day survival was 2.45 (95% CI: 1.02-5.95). CONCLUSIONS: The use of AEDs before the arrival of EMS increased over time. This was associated with an increased 30-day survival among patients with VF. Thirty-day survival was highest when an AED was used on site before EMS arrival.

Dravet syndrome--considerable delay in making the diagnosis.

OBJECTIVES: To assess delay in diagnosis and clinical characteristics of Dravet syndrome based on the Dravet register at The National Centre for Epilepsy in Norway. MATERIAL AND METHODS: Medical records of patients diagnosed with Dravet syndrome since 2007 were analysed. RESULTS: Twenty-two patients were identified. In 15, genetic screening disclosed mutations/deletions in the SCN1A gene. Average time from seizure onset to diagnosis was 7.4 years. Mean age at seizure onset was 6.7 months, nine had hemiconvulsions and 13 had generalized tonic-clonic seizures. The seizures were precipitated by fever in 17, by external heating in three. During second year of life, multiple seizure types and cognitive and motoric stagnation occurred. No patients became seizure-free with antiepileptic drugs. The effect of vagal nerve stimulation was disappointing. CONCLUSIONS: By making an early diagnosis, an extensive presurgical evaluation may be avoided, and the patient and their parents may be offered genetic guidance.

Characteristics and motivational factors for joining a lay responder system dispatch to out-of-hospital cardiac arrests.

BACKGROUND: There has been in increase in the use of systems for organizing lay responders for suspected out-of-hospital cardiac arrests (OHCAs) dispatch using smartphone-based technology. The purpose is to increase survival rates; however, such systems are dependent on people's commitment to becoming a lay responder. Knowledge about the characteristics of such volunteers and their motivational factors is lacking. Therefore, we explored characteristics and quantified the underlying motivational factors for joining a smartphone-based cardiopulmonary resuscitation (CPR) lay responder system. METHODS: In this descriptive cross-sectional study, 800 consecutively recruited lay responders in a smartphone-based mobile positioning first-responder system (SMS-lifesavers) were surveyed. Data on characteristics and motivational factors were collected, the latter through a modified version of the validated survey "Volunteer Motivation Inventory" (VMI). The statements in the VMI, ranked on a Likert scale (1-5), corresponded to(a) intrinsic (an inner belief of doing good for others) or (b) extrinsic (earning some kind of reward from the act) motivational factors. RESULTS: A total of 461 participants were included in the final analysis. Among respondents, 59% were women, 48% between 25 and 39 years of age, 37% worked within health care, and 66% had undergone post-secondary school. The most common way (44%) to learn about the lay responder system was from a CPR instructor. A majority (77%) had undergone CPR training at their workplace. In terms of motivation, where higher scores reflect greater importance to the participant, intrinsic factors scored highest, represented by the category values (mean 3.97) followed by extrinsic categories reciprocity (mean 3.88) and self-esteem (mean 3.22). CONCLUSION: This study indicates that motivation to join a first responder system mainly depends on intrinsic factors, i.e. an inner belief of doing good, but there are also extrinsic factors, such as earning some kind of reward from the act, to consider. Focusing information campaigns on intrinsic factors may be the most important factor for successful recruitment. When implementing a smartphone-based lay responder system, CPR instructors, as a main information source to potential lay responders, as well as the workplace, are crucial for successful recruitment.

The structure of the F-actin filament and the actin molecule.

A consensus view on the three-dimensional structure of the F-actin filament and the relative strength of the intersubunit contacts in the filament has been established from an atomic filament model and recent three-dimensional reconstructions from electron micrographs of F-actin filaments. Functional implications of recent structural and biochemical data indicating a rather dynamic filament structure are discussed.

Femur ultrasound (FemUS)--first clinical results on hip fracture discrimination and estimation of femoral BMD.

SUMMARY: A quantitative ultrasound (QUS) device for measurements at the proximal femur was developed and tested in vivo (Femur Ultrasound Scanner, FemUS). Hip fracture discrimination was as good as for DXA, and a high correlation with hip BMD was achieved. Our results show promise for enhanced QUS-based assessment of osteoporosis. INTRODUCTION: Dual X-ray absorptiometry (DXA) at the femur is the best predictor of hip fractures, better than DXA measurements at other sites. Calcaneal quantitative ultrasound (QUS) can be used to estimate the general osteoporotic fracture risk, but no femoral QUS measurement has been introduced yet. We developed a QUS scanner for measurements at the femur (Femur Ultrasound Scanner, FemUS) and tested its in vivo performance. METHODS: Using the FemUS device, we obtained femoral QUS and DXA on 32 women with recent hip fractures and 30 controls. Fracture discrimination and the correlation with femur bone mineral density (BMD) were assessed. RESULTS: Hip fracture discrimination using the FemUS device was at least as good as with hip DXA and calcaneal QUS. Significant correlations with total hip bone mineral density were found with a correlation coefficient R (2) up to 0.72 and a residual error of about one half of a T-score in BMD. CONCLUSIONS: QUS measurements at the proximal femur are feasible and show a good performance for hip fracture discrimination. Given the promising results, this laboratory prototype should be reengineered to a clinical applicable instrument. Our results show promise for further enhancement of QUS-based assessment of osteoporosis.

The structural basis for the intrinsic disorder of the actin filament: the "lateral slipping" model.

Three-dimensional (3-D) helical reconstructions computed from electron micrographs of negatively stained dispersed F-actin filaments invariably revealed two uninterrupted columns of mass forming the "backbone" of the double-helical filament. The contact between neighboring subunits along the thus defined two long-pitch helical strands was spatially conserved and of high mass density, while the intersubunit contact between them was of lower mass density and varied among reconstructions. In contrast, phalloidinstabilized F-actin filaments displayed higher and spatially more conserved mass density between the two long-pitch helical strands, suggesting that this bicyclic hepta-peptide toxin strengthens the intersubunit contact between the two strands. Consistent with this distinct intersubunit bonding pattern, the two long-pitch helical strands of unstabilized filaments were sometimes observed separated from each other over a distance of two to six subunits, suggesting that the intrastrand intersubunit contact is also physically stronger than the interstrand contact. The resolution of the filament reconstructions, extending to 2.5 nm axially and radially, enabled us to reproducibly "cut out" the F-actin subunit which measured 5.5 nm axially by 6.0 nm tangentially by 3.2 nm radially. The subunit is distinctly polar with a massive "base" pointing towards the "barbed" end of the filament, and a slender "tip" defining its "pointed" end (i.e., relative to the "arrowhead" pattern revealed after stoichiometric decoration of the filaments with myosin subfragment 1). Concavities running approximately parallel to the filament axis both on the inner and outer face of the subunit define a distinct cleft separating the subunit into two domains of similar size: an inner domain confined to radii less than or equal to 2.5-nm forms the uninterrupted backbone of the two long-pitch helical strands, and an outer domain placed at radii of 2-5-nm protrudes radially and thus predominantly contributes to the outer part of the massive base. Quantitative evaluation of successive crossover spacings along individual F-actin filaments revealed the deviations from the mean repeat to be compensatory, i.e., short crossovers frequently followed long ones and vice versa. The variable crossover spacings and diameter of the F-actin filament together with the local unraveling of the two long-pitch helical strands are explained in terms of varying amounts of compensatory "lateral slipping" of the two strands past each other roughly perpendicular to the filament axis. This intrinsic disorder of the actin filament may enable the actin moiety to play a more active role in actin-myosin-based force generation than merely act as a rigid passive cable as has hitherto been assumed.

Inhibition of renal tubular transport of methotrexate by probenecid.

The mechanism of excretion of methotrexate (MTX) has been investigated in the monkey. Under steady-state conditions of varied plasma levels of MTX, it was determined that MTX was excreted by renal tubular transport as well as by glomerular filtration. The maximum rate of renal tubular transport of MTX (81 mug/min) was attained at plasma levels of MTX from 6 to 8 mug/ml. Correspondingly, the rate of clearance of MTX from plasma was shown to diminish from a value that was 3-fold greater than the glomerular filtration rate at plasma levels of MTX from 6 to 32 mug/ml. Pretreatment of animals with probenecid (700 mg/sq m) totally inhibited renal tubular transport of MTX when MTX was administered in doses from 1.8 to 621 mg/sq m. Following inhibition of renal tubular transport of MTX by probenecid, steady-state plasma levels of MTX in animals pretreated with probenecid (700 mg/sq m) was reduced by a factor of 2.6 from values determined in non-probenecid-pretreated control animals receiving similar varied doses of MTX (1.8 P to greater than 600 mg/sq m). The mode of i.v. injection of MTX was seen to effect the concentration of MTX in plasma. Initial loading followed by continuous sustaining infusion of MTX provided stable and higher levels of MTX in plasma than was determined in controls or in experimental animals pretreated with probenecid and receiving identical doses of MTX by single bolus injection.

Use of complementary and alternative medicine by patients with cancer: a cross-sectional study at different points of cancer care.

Complementary and alternative medicine (CAM) is widely used by cancer patients. In order to learn more on the usage of CAM, its reasons and motifs as well as sources of information along the trajectory of treatment, we decided to evaluate the prevalence and predictors for the use of CAM by cancer patients while being under active treatment with chemo- or radiotherapy or in aftercare. We distributed a standardized questionnaire among patients attending a department of radio-oncology, an ambulance for oncology and offices of general practitioners (GPs). Five hundred and six patients took part. Most attributed cancer to stress and trauma (23.7 and 16.4 %) or genes (20.8 %). Forty-four percentage reported knowing a physician with competence in CAM, and in all settings, most patients named the GP. Fifty-one percentage admitted using CAM, 35 % informed the oncologist about using CAM, 56 % informed the GP, and 26 % did not inform any physician. Most often used CAM was vitamin D (17 %) and selenium (16 %). Most important goals were to strengthen the immune system (59 %) and become active (52 %). Most patients were satisfied with the CAM methods they used. Yet, with some methods, dissatisfaction was up to 30 %. The GP has an important function concerning CAM in oncology as most patients believe the GP to have best knowledge in CAM. In order to integrate complementary medicine into evidence-based medicine, physicians should be trained on how to communicate on CAM with the patient and with each other. Explaining cancer and cancer therapies in a way lay persons are able to understand may be helpful. Physicians should actively address patients' needs of involvement not only in decision making, but also actively in the therapy.

Towards atomic interpretation of F-actin filament three-dimensional reconstructions.

We have recorded dark field images of negatively stained F-actin filaments polymerized with 2 mM MgCl2 and 50 mM KCl with a scanning transmission electron microscope and computed 3-D reconstructions using a helical parameter search to optimize simultaneously the helical repeat length, the radial position of the filament axis, and the helical selection rule. The resulting optimized averaged filament 3-D reconstruction at 2.5 nm resolution is remarkably similar to an atomic model of the F-actin filament. By comparison, several structural features of the reconstruction can be interpreted at the level of distinct secondary structure elements, and predictions made by the atomic model could be verified: for instance, the density connecting the two long-pitch helical strands in our reconstruction co-localizes with an extended beta-hairpin, the "hydrophobic loop" (i.e. residues 262 to 274), which according to the atomic model establishes the major intersubunit contact between the two long-pitch helical strands. The most pronounced structural variations among individual filament 3-D reconstructions were observed in (1) the details of the intersubunit contact pattern between the two long-pitch helical strands, and (2) the exact size and shape of subdomain 2 of the F-actin molecule, which appears rather flexible and easily deformed. In addition, we found that all phenotypes of F-actin filament 3-D reconstructions that arise from small deviations from the optimal helical parameters or from lowering the nominal resolution exhibited stronger intersubunit contacts between than along the two long-pitch helical strands, a structural feature that has been emphasized for a number of F-actin filament 3-D reconstructions in the past. Since this is clearly at variance with the relative strength of the intersubunit contacts as predicted by the atomic model, it may represent an artifactual structural feature arising from low-resolution data or suboptimal helical data processing, and should therefore be interpreted with caution in terms of indicating chemical, mechanical or conformational states of the F-actin filament.

The common C-terminal sequences of substance P and neurokinin A contact the same region of the NK-1 receptor.

Although neurokinin A (NKA), a tachykinin peptide with sequence homology to substance P (SP), is a weak competitor of radiolabeled SP binding to the NK-1 receptor (NK-1R), more recent direct binding studies using radiolabeled NKA have demonstrated an unexpected high-affinity interaction with this receptor. To document the site of interaction between NKA and the NK-1R, we have used a photoreactive analogue of NKA containing p-benzoyl-L-phenylalanine (Bpa) substituted in position 7 of the peptide. Peptide mapping studies of the receptor photolabeled by (125)I-iodohistidyl(1)-Bpa(7)NKA have established that the site of photoinsertion is located within a segment of the receptor extending from residues 178 to 190 (VVCMIEWPEHPNR). We have previously shown that (125)I-BH-Bpa(8)SP, a photoreactive analogue of SP, covalently attaches to M(181) within this same receptor sequence. Importantly, both of these peptides ((125)I-iodohistidyl(1)-Bpa(7)NKA and (125)I-BH-Bpa(8)SP) have the photoreactive amino acid in an equivalent position within the conserved tachykinin carboxyl-terminal tail. In this report, we also show that site-directed mutagenesis of M(181) to A(181) in the NK-1R results in a complete loss of photolabeling of both peptides to this receptor site, indicating that the equivalent position of SP and NKA, when bound to the NK-1R, contact the same residue.

Clinical and radiologic remission in reticulum cell sarcoma of the brain.

Two patients with cerebral reticulum cell sarcoma (CRCS) are reported in whom neurologic abnormalities and radiologic (computerized tomographic [CT] scan) evidence of tumor remitted. In one patient, remission followed craniectomy and corticosteroid therapy and lasted for eight months. In the other patient, at least four remissions occurred over a span of seven years, each in conjunction with the administration of corticosteroids. Corticosteroids may favorably alter the biologic activity of tumor tissue in some cases of CRCS, predisposing to clinical remission and disappearance of tumor on CT scan.

Direct evidence for the interaction of neurokinin A with the tachykinin NK(1) receptor in tissue.

Neurokinin A (NKA) is a tachykinin peptide that binds with high affinity to the tachykinin NK(2) receptor. Recent homologous binding studies, however, have shown that neurokinin A is also a high-affinity ligand for the tachykinin NK(1) receptor. In this report, we demonstrate that a photoreactive neurokinin A analogue specifically labels the NK(1) receptor in rat submandibular gland membranes and show via bioassay that neurokinin A is a potent stimulator of salivary secretion. Through the use of specific non-peptide antagonists in both photolabeling and functional assays, we unequivocally demonstrate that neurokinin A can specifically interact with the NK(1) receptor in vivo and elicit NK(1) receptor-mediated physiological responses.

Internal metal plate fixation combined with anterior interbody fusion in cases of cervical spine injury.

The authors report their experience with the use of a modified method of internal metal plate fixation combined with anterior interbody fusion in six patients with an unstable lower cervical spine. All of the patients had sustained severe cervical spine injuries in accidents. In most of the cases, the operation was carried out at 1 to 4 weeks after injury. The insertion of the metal plate was very simple and maintained the block bone graft in satisfactory position. This alternative method of internal fixation of the cervical spine was not associated with morbidity, allowed very early mobilization, and shortened the hospital stay.

Basilar artery occlusion in multiple trauma: case report.

The authors report a patient who sustained delayed occlusion of the basilar artery (BA) after an automobile accident. This report illustrates the clinical temporal profile of angiographically verified thromboembolic occlusion of the BA. Further propagation of thrombosis and/or late embolization in the proximal BA and distal vertebral artery resulted in fatal brain stem infarction.

Alterations in cortical oxygen tension during the development of ischemic cerebral edema in primates (Macaca mulatta).

With a closed head primate stroke model, acute cerebral ischemia limited to the middle cerebral artery (MCA) territory was produced by macrosphere embolization of the internal carotid artery bifurcation. Measurements of the oxygen tension (PO2) at the cerebral cortical surface were obtained by continuous on-line mass spectrometry. Percentage of dry weight and tissue sodium, potassium, and chloride concentrations from ischemic and nonischemic hemispheres were determined at various times. With this preparation, we registered the precise onset of cortical surface PO2 depletion, which showed an exponential downward trend (fast component from 0 to 5 minutes, t 1/2 = 0.8 minute, rate of change = 89% per minute; slow component from 5 to 240 minutes, t 1/2 = 285 minutes, rate of change = 0.3% per minute). After the onset of cerebral ischemia, there was an immediate fall of the cortical surface PO2 with reductions of more than 45% at 5 minutes before definite hemiparesis and electroencephalographic abnormalities were recognized. During the secondary phase from 5 to 240 minutes the cortical surface PO2 fell by only an additional 23% of the steady state. Even so, when cortical surface PO2 was maintained at this critically low level, the earliest cerebral cortical edema was evident 180 minutes after MCA occlusion. Thereafter, progressive accumulation of edema fluid in the cortex (90 to 170.8 microliters per g of tissue) and in the white matter (19 to 46.2 microliter per g of tissue) was detected by the end of 240 minutes of cerebral ischemia.

Ischemic cerebral edema in primates: effects of acetazolamide, phenytoin, sorbitol, dexamethasone, and methylprednisolone on brain water and electrolytes.

Brain edema was induced in primates (Macaca mulatta) after regional cerebral ischemia produced by selective embolization of the internal carotid artery bifurcation. Details of the alterations in the distribution of water and electrolytes in the brain during the evolution of ischemic cerebral edema have been described elsewhere. The effects of five theoretically useful pharmacological agents were studied. Acetazolamide failed to improve ischemic edema and, rather, increased mortality. Phenytoin definitely prevented both edema and infarction in only the cerebral cortex. Sorbitol was effective to induce dehydration of the affected cortex and the normal brain tissue, with obvious reduction of the brain bulk. High dose steroids showed an ability to modify edema in the cortex, putamen, and white matter. However, animals treated with methylprednisolone rather than dexamethasone showed a better neurological recovery and smaller infarcts.

Autogeneic fat transplants in the epidural space in routine lumbar spine surgery.

This report presents our experience with the use of autogeneic fat patch grafts to protect the exposed dura mater during lumbar spine operations. A total of 44 consecutive surgical procedures was performed primarily for discogenic or spondylotic disease from 1979 to 1982. Prophylactic antibiotics were used in 21 (48%) cases. The autogeneic fat transplants were well accepted by all recipients during 10.4 (1 to 32) months of follow-up. Fat grafts, greater than 1 cm in thickness, were easily identified on subsequent computed tomographic (CT) scans. There were no postoperative wound infections. However, 1 patient developed a large subcutaneous sterile fluid accumulation at the fat donor site, which required surgical intervention. Our results, both short and long term, indicate that autogeneic fat transplants may be well tolerated in the lumbar spine area. The fat graft viability as demonstrated by CT scanning and histological examination supports the contention that autogeneic fat interposed between dura mater and overlying musculature may serve as a barrier limiting the growth of cicatrix into the spinal canal.

An unusual late complication of acrylic spinal fusion: case report.

The authors report an unusual complication after posterior cervical spine fusion utilizing methyl methacrylate and metallic pins. Eight months postoperatively, the patient noticed a subcutaneous foreign body in the right side of the neck. Radiographic and operative findings confirmed the clinical impression of migration of one of the metallic pins.

Pneumocephalus secondary to tension pneumothorax associated with comminuted fracture of the thoracic spine.

We present an unusual case of pneumocephalus secondary to a tension pneumothorax associated with fracture of the thoracic spine. Air from a pneumothorax entered the thoracic intraspinal compartment and the intracranial cavity through a comminuted fracture of the spine. The pneumocephalus and the pneumothorax resolved after aspiration of the intrathoracic air via an intercostal catheter. Diagnosis, therapeutic modalities, and potential complications of a pneumocephalus and of a communication between the thoracic cavity and the spinal dural space are discussed.