Influence of Electromagnetic Fields on Function of Automated External Defibrillators

Objectives: In this study, the authors tested whether electromagnetic interference (EMI) is able to impair correct electrocardiogram analysis and produce false‐positive shock advice from automated external defibrillators (AEDs) when the true rhythm is sinus. Methods: Nineteen healthy subjects were used to test five AEDs available on the Austrian market in a prospective, open, and sequence‐randomized study. The primary outcome variable was the absolute number of shocks advised in the presence of EMI. The secondary outcome was the number of impaired analyses caused by incorrectly detected patient movements or electrode failure. Results: Of 760 tests run, 18 (2.37%) cases of false‐positive results occurred, and two of five AEDs recommended shocks in the presence of sinus rhythm. Of 760 tests run, no electrode failures occurred. There were 27 occurrences (3.55%) of motion detected by an AED in the presence of strong electromagnetic fields. Conclusions: AED models differ in their response to EMI; it may be useful to consider specific safety requirements for areas with such fields present. Working personnel and emergency medical services staff should be informed about potential risks and the possible need for patient evacuation before AEDs are attached and shock recommendations are followed.     

Outcome treatment of pseudoarthrosis of long bones with decortication method depends on osteosynthesis]

Purpose of work was estimation of the results of treatment of pseudoarthrosis of the long bone with the method of decortication, with use of autogenic bone depends on kind of pseudoarthrosis and kind of osteosynthesis. In the years 1995-2005 56 patients were treated because of pseudoarthrosis of long bone in our Clinic. Pseudoarthrosis is classified according to Weber-Cech classification. In the methodology of clinical estimation and subjective estimation of the patient Stewart and Hundley and Anderson classification were used. Union was achieved in 51 cases. Time of bone union achievement was 5 months. The results of treatment are depends on morfology of pseudoartrosis and are independs of kind of osteosynthesis.     

Disseminating tumor cells and their interactions with leukocytes visualized in the brain.

Brain tumors are increasingly prevalent. Recent advances focus attention on individual, disseminated tumor cells that cannot be imaged or eliminated. Cells of the immune system may be ideally suited to attack individual tumor cells, but more basic understanding is needed. We describe a rat model, using the lacZ reporter gene, that allows identification of individual tumor cells, and tumor-leukocyte interactions in vivo. The model demonstrates how widely tumor can disseminate, without secondary tumorigenesis or recruitment of nonneoplastic cells. It demonstrates that leukocytes have access to disseminating tumor. Among its many applications, this work lays a foundation for developing cell-mediated immunotherapy against individual brain tumor cells.     

Sympathetic reinnervation after heart transplantation, assessed by iodine-123 metaiodobenzylguanidine imaging, and heart rate variability.

OBJECTIVE: Complete allograft denervation occurs during heart transplantation. Partial ventricular sympathetic reinnervation may develop one year or later after transplantation and can be measured with iodine-123-meta-iodobenziylguanidine (MIBG) uptake. Aim of this study was to assess sinus node sympathetic reinnervation measured with heart rate variability and ventricular sympathetic reinnervation evaluated with MIBG. METHODS: Twelve patients and 14 healthy controls were included. In patients, MIBG scintigraphy with early and late imaging was performed. Heart to mediastinum ratio (HMR) was calculated and patients were divided in groups with (HMR>1.3) and without left ventricular reinnervation (HMR<1.3). Bipolar ECG with high sampling rate and resolution was recorded over 8.5 min in supine position and in upright position after 10 min interval. R-R intervals in time domain and heart rate variability in frequency domain through spectral power analysis of R-R intervals were analysed to evaluate sinus node reinnervation. Spectral power in low frequency range (0.04-0.15 Hz) above 4.5 ms(2) was considered as sinus node sympathetic reinnervation. RESULTS: Six (50%) patients had evidence of left ventricular sympathetic reinnervation on scintigraphy. Sinus node sympathetic reinnervation based on heart rate variability was detected in 6 (50%) patients in supine, and in 4 (33%) patients in upright body position. Four patients groups were discerned: (1) with ventricular and sinus node sympathetic reinnervation, (2) with sinus node sympathetic reinnervation, (3) with ventricular sympathetic reinnervation and (4) without atrial or ventricular sympathetic reinnervation. Ventricular reinnervation process was time dependent and sinus node reinnervation was not. CONCLUSIONS: Simultaneous ventricular sympathetic reinnervation assessed by MIBG and sinus node sympathetic reinnervation assessed by heart rate variability in supine as in upright position were detected only in two patients (17%). The results of our study show that eventual sinus node sympathetic reinnervation and left ventricular sympathetic reinnervation do not occur simultaneously.     

Hip arthroplasty after failed internal fixation of the trochanteric fractures in aged patients with co-existent osteoporosis]

The authors present the results of hip arthroplasty of 67 patients treated after failed internal fixation of the osteoporotic, trochanteric fractures of the femur, which were primary stabilised with angular plate AO in 39 patients and with dynamic hip screw (DHS) in 28 patients. In the discussed material 16 persons were male and 51 female, in the age between 51 and 83 years old. According to the Evans classification in 4 cases we diagnosed type I of fracture, in 10--type II, 31--type III and in 22--type IV. Hip arthroplasty was made from the 3rd to the 39th week after primary fixation of the fracture. In 42 patients we made total hip arthroplasty, in 14 cases Austin-Moore hemiarthroplasty, and in 11 patients bipolar arthroplasty. According to the Postel and Merle d'Aubigne classification there were obtained 29 very good, 21 good and 17 satisfactory results.     

Lipophilic platinum complexes entrapped in liposomes: improved stability and preserved antitumor activity with complexes containing linear alkyl carboxylato leaving groups

Lipophilic diaminocyclohexane (DACH) platinum complexes have shown significant promise in preclinical studies. One of these compounds,cis-bis-neodecanoato-trans-R,R-1,2-diaminocyclohexaneplatinum(II) (NDDP), which contains two branched leaving groups of 10 carbons, showed a favorable toxicity profile in a liposomal formulation in early clinical trials. However, like many other DACH platinum compounds with branched leaving groups, it is unstable within the liposomes, thus preventing its widespread clinical evaluation. We studied the effect of the configuration of leaving groups on intraliposomal complex stability by studying a series of DACH platinum complexes containing linear alkyl carboxylato leaving groups of 5–18 carbons. The entrapment efficiency was greater than 90% for all liposomal preparations of the complexes and was independent of lipid composition and length of the leaving group. The drug leakage from the liposomes was minimal, but was directly related to the length of the leaving group. Intraliposomal stability was inversely related to the length of the leaving group and the content of DMPG (dimyristoyl phosphatidylglycerol) in the liposomes. The effect of length of leaving group on intraliposomal stability was minimal in compounds with leaving groups smaller than 10 carbons, but very pronounced in compounds with longer leaving groups. Stable liposomal formulations of selected compounds with leaving groups of 6 and 10 carbons had significant in vivo antitumor activity against both L1210/S and L1210/PDD leukemias. The results indicate (1) that compounds with linear leaving groups are much more stable within DMPG-containing liposomes than compounds with branched leaving groups and (2) that DMPG is required for in vivo antitumor activity. Stable and active liposomal formulations of selected compounds with linear leaving groups have been identified. These formulations are candidates for clinical development.Abbreviations DMPC dimyristoyl phosphatidylcholine - DMPG dimyristoyl phosphatidylglycerol - L-NDDP liposomalcis-bis-neodecanoato-trans-1,2-diaminocyclohexaneplatinum(II) The work reported in this paper was supported in part by NIH grants CA 41581, 45423, 50270, and 58342     

Radiation therapy of testicular seminoma: a 15-year survey.

A retrospective review of 69 patients with testicular seminoma, stage I and II, treated by orchiectomy and adjuvant irradiation at McGill University Hospitals from 1972 to 1987 was performed. All patients underwent either lymphangiogram or computed axial tomography scan for evaluation of retroperitoneal disease. There were 52 stage I (75%), 13 stage IIA (11%), 2 stage IIB (3%), and 2 stage IIC (Royal Marsden Hospital staging criteria). Median follow-up time was 6.2 years. The 10-year actuarial survivals were 94% and 93% for stages I and II, respectively. Only two stage I patients failed treatment, and both died from metastatic disease. Interestingly, both developed biopsy-proven metastatic brain disease and had no evidence of intra-abdominal recurrence. In stage II disease, only one patient failed the treatment. There was no serious acute toxicity and no late complications have been encountered. Radiation therapy following orchiectomy is the treatment of choice for stage I and for most stage II patients with testicular seminoma. The controversial aspects of radiographic retroperitoneal staging, the use of prophylactic mediastinal irradiation for stage II patients, and the role of surveillance only for stage I patients are discussed.     

Delayed-type hypersensitivity elicited by synthetic peptides complexed with Mycobacterium tuberculosis hsp 70.

Four synthetic peptides bearing dominant CD4+ T-cell epitopes of the 19,000 and 38,000 MW proteins of Mycobacterium tuberculosis were used to provoke a delayed-type hypersensitivity (DTH) reaction in mice previously immunized with recombinant 19,000 and 38,000 MW proteins. It was found that an effective enhancement of the DTH reaction was obtained if the peptides were administered as a complex with M. tuberculosis hsp 70 protein. The increase in reactivity was not obtained when hsp 70 and peptide were co-injected at the same site, but not in complex, or when the specific peptide was displaced from the complex by an irrelevant peptide with high capacity to bind hsp 70. One of the antigenic peptides whose capacity to complex with hsp 70 is low, failed to show the enhancement of DTH when injected together with hsp 70.     

Butyrate infusions in the ovine fetus delay the biologic clock for globin gene switching.

The switch from fetal to adult hemoglobin expression is regulated in many mammalian species by a developmental clock-like mechanism and determined by the gestational age of the fetus. Prolonging fetal globin gene expression is of considerable interest for therapeutic potential in diseases caused by abnormal beta-globin genes. Butyric acid, which is found in increased plasma concentrations in infants of diabetic mothers who have delayed globin gene switching, was infused into catheterized fetal lambs in utero during the time of the normal globin gene switch period. The globin gene switch was significantly delayed in three of four butyrate-treated fetuses compared with controls and was entirely prevented in one fetus in whom the infusion was begun before the globin switch was under way. These data provide a model for investigating and arresting the biologic clock of hemoglobin switching.     

Behavioral dissociation of anterodorsal and posteroventral hippocampus by subseizure stimulation in mice

BALB/c mice were bilaterally implanted with bipolar electrodes either in anterodorsal (ADH) or posteroventral hippocampus (PVH) in order to compare the effects of postsession electrical stimulation on memory processes. For each experiment, 30 s after the end of the first session, the animals were stimulated during 80 s. For both hippocampal regions, the stimulation intensity was half of the afterdischarge threshold value. Control groups were naive, ADH and PVH implanted non-stimulated animals. Different appetitive and aversive tasks were used. Subseizure stimulation never created a deficit. Depending on the region of the hippocampus stimulated and on the learning task, a retention enhancement was eventually observed. These data are in agreement with the involvement of hippocampus in initial stages of memory consolidation. Further, the subseizure stimulation permitted a functional dissociation between the two hippocampal regions. Both regions seemed involved in the integration of information, but the anterodorsal part would be rather related to behavioral inhibition, while the posteroventral part would have the capacity to induce an arousal state allowing behavioral flexibility.