Residual leukemic cell counts in the bone marrow at the end point of intensive induction therapy may be a prognostic factor for acute myeloblastic leukemia in adults

Many studies analyzing interactions of pH and bioelectric activity focus on changes of the extracellular pH, whereas data concerning central neuronal excitability and intracellular pH (pHi) are rare. Here, we report on the spontaneous bioelectric activity and epileptiform activity of CA3-neurons during a procedure which changed pHi. As monitored in BCECF-AM loaded cells, the change from a CO2/HCO3(-)-buffered to a HEPES-buffered medium (CO2/HCO3(-)-withdrawal, hereafter termed W) was associated with a transient intracellular alkalosis (delta pH = 0.2 +/- 0.04) which preceded a sustained intracellular acidosis (delta pH = 0.4 +/- 0.04). Coinciding with this W-induced biphasic shift of pHi a biphasic alteration of spontaneous bioelectric activity was recorded: as a rule, an up to 30 min lasting increase (excitatory phase) preceded a typical sustained suppression (inhibitory phase). This biphasic action was also observed using various in vitro-epilepsy-models (bicuculline, penicillin, caffeine): epileptiform discharges were completely suppressed after an initial increase in frequency. This modulation of bioelectric activity was unlikely due to alterations of the postsynaptic GABA-system as hyperpolarizing GABAA- and GABAB-responses of CA3-neurons were hardly affected. In the majority of the neurons, the initial increase of spontaneous bioelectric activity (excitatory phase) culminated in transient burst periods lasting 5-30 min. These transient burst periods were blocked by NMDA- or AMPA-antagonists: DL-2-amino-5-phosphonovalerate (APV, 50 microM) or 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, 50 microM). The calcium-antagonist verapamil (50 microM) reduced amplitudes of depolarizations and duration of the transient burst periods. The results suggest that the biphasic alteration of pHi modulates the susceptibility of glutamate receptors and voltage-gated calcium-channels, which leads to respective changes of bioelectric activity.     

CT analysis of the anterior mediastinal fat: before and after lobectomy

CT analysis was performed to evaluate change in the anterior mediastinal fat (AMF) after lobectomy and differences in AMF in the lobectomized region. In 67 carcinoma patients who underwent lobectomy, the area and volume of AMF were measured on CT before and after surgery. Mediastinal deviation after lobectomy was also correlated to the altered fat tissue. The postoperative AMF distribution was distinctly changed in the left upper lobectomy (LUL) group, showing a marked increase from the infra-aortic arch to the carina level, with converse decreases in upper and lower slices. No significant post-operative change was noted in total AMF volume. There was a close correlation between changes in AMF area and mediastinal deviation after lobectomy, and postoperative mediastinal deviation was also greater the in the LUL group than in any other group. In conclusion, postoperative change in the AMF area was distinctly different in the LUL group. Redistribution of displaced AMF is considered to be the main cause of seemingly increased fat tissue.     

EEG and clinical studies of the development of alumina cream epileptic focus in split-brain cats

Alumina cream epileptic focus was established in the right sensorimotor cortex in 20 split-brain cats (partial or complete). EEG and behavioral observations were made in a period ranging from 24 to 836 days. Four types of EEG changes after alumina cream injection were differentiated. These types could be related to the direct effects of brain damage and to development of epilepsy. Spikes and sharp waves and paroxysmal discharges (focal and multifocal) were observed in about 60% of the cats. Clinical seizures developed in about the same percentage of the animals. These values are below those reported for cats with intact interhemispheric commissures. Diphenylhydantoin (DPH) was given orally in a daily dose of up to 15 mg/kg body weight in 9 animals with developed epileptic EEG activity. Five of them had epileptic seizures. DPH was introduced not earlier than 1.5 months after intracortical alumina cream injection. The plasma level of DPH varied between 7-20 mug/ml. This dose produced chronic symptoms of intoxication. Neither EEG changes nor clinical seizures were entirely controlled by this drug. Additional doses of Relanium (diazepam), and phenobarbital were necessary to stop generalized seizures or status epilepticus.     

Coating evolution with an implantable biological battery

A cathode of smooth platinum in a right endoatrial position and an anode of Domal magnesium were used to construct a hybrid bioelectric battery designed to power a pacemaker. In use the cathode is gradually covered by a coating consisting of a crystalline layer and a layer of connective tissue. This coating is responsible for the system change in the reduction process at the cathode level: the transfer from an oxygen to a hydrogen system. This system change causes a voltage drop in the bioelectric battery. This paper deals with oxygen diffusion across the tissue layer, as well as with various spectral and chemical analyses. A high level of calcium and phosphorus in the different analyses carried out seems to show that the presence of these elements is related to the coating of the cathode. The effect on the formation of the coating of the position of the cathode is also discussed.     

Effect of the rolling temperature on the structure and the mechanical properties of high-nitrogen austenitic steels 05Kh21G9N7AMF and 04Kh22G12N4AMF

The structure and the mechanical properties of high-nitrogen austenitic 05Kh21G9N7AMF (0.56% N) and 04Kh22G12N4AMF (0.49% N) steels have been studied after hot rolling. It is found that the temperatures of the onset and end of hot deformation influence the structure and the mechanical properties of these steels. The higher set of mechanical properties of steel 05Kh21G9N7AMF after rolling in the temperature range 1100–900°C is due to the formation of a lamellar and equiaxed fragmented structure.     

Quantitative analysis of interictal behavior in temporal lobe epilepsy

Patients with unilateral temporal epileptic foci were contrasted with normal subjects and patients with neuromuscular disorders in the evaluation of specific psychosocial aspects of behavior. Eighteen traits were assessed in equivalent questionnaires completed by both subjects and observers. The epileptic patients self-reported a distinctive profile of humorless sobriety, dependence, and obsessionalism; raters discriminated temporal lobe epileptics on the basis of circumstantiality, philosophical interests, and anger. The right temporal epileptic displayed emotional tendencies in contrast to ideational traits of left temporal epileptic. Right temporal epileptics exhibited "denial," while left temporal epileptics demonstrated a "catastrophic" overemphasis of dissocial behavior. The results support the hypotheses that sensory-affective associations are established within the temporal lobes, and that, in man, there exists a hemispheric asymmetry in the expression of affect.     

Cortical vascular abnormalities in the syndrome of celiac disease, epilepsy, bilateral occipital calcifications, and folate deficiency

The pathological changes in the syndrome of celiac disease, folate deficiency, bilateral occipital calcifications, and intractable epilepsy have not been previously described. A child with this disorder had a field defect correlating with active lateralized epileptic discharges and asymmetrical lesions. After resection of the right occipital lobe she was seizure free for 4 years. A cortical vascular abnormality with patchy pial angiomatosis, fibrosed veins, and large jagged microcalcifications was found. These pathological abnormalities were similar though not identical to those found in the Sturge-Weber syndrome.     

Distribution of hepatic glycosaminoglycans during acute schistosomiasis: modulation by IFN gamma treatment

The neuropsychological characteristics of frontal lobe epilepsy have rarely been reported, with neuropsychological indicators usually being related to subjects with other forms of neurological damage. In this study we assessed the performance of 74 subjects with frontal lobe epilepsy (42 with left, 32 with right frontal epileptic foci) on a series of measures thought to be sensitive to frontal lobe dysfunction and compared to 57 subjects with temporal lobe epilepsy (31 with left, 26 with right epileptic foci). The results indicated a number of measures that could be considered sensitive to frontal lobe epileptic dysfunction. However, the pattern of results did not indicate consistent deficits to be associated with frontal lobe epileptic dysfunction. There are a number of unique factors associated with epilepsy that need to be considered, and these may account for the variable pattern of results obtained. In particular, the rapid propagation of frontal lobe seizures both bilaterally and to other cortical regions has to be considered.     

Auditory middle latency responses in patients with epilepsy

Middle latency auditory responses (MLRs) were studied in 55 normal subjects and 49 epileptic patients. We evaluated the function of the auditory system and of the temporal lobe in epileptic patients using MLRs. (1) The patients with epilepsy had significantly prolonged Pa and Nb latencies and the significantly increased amplitude of Pa-Nb component. (2) The prolongation and the increase of MLR components in latency and amplitude were more obvious in patients with intractable epilepsy than patients without intractable epilepsy. (3) The difference between left and right sides was larger in epileptic patients than normal subjects. (4) Epileptic patients with polypharmacy had reduced amplitude of Pa-Nb component and prolonged latency of Pa component than patients with monotherapy. Antiepileptic drugs (AEDs) appeared to decrease the amplitude of Pa-Nb component. It was supposed that the enhancement of amplitude of Pa-Nb component represented the abnormality of central nerve system in epileptic patients, in part.     

Hemispheric contributions to the integration of visual and auditory information in speech perception

Differential hemispheric contributions to the perceptual phenomenon known as the McGurk effect were examined in normal subjects, 1 callosotomy patient, and 4 patients with intractable epilepsy. Twenty-five right-handed subjects were more likely to demonstrate an influence of a mouthed word on identification of a dubbed acoustic word when the speaker's face was lateralized to the LVF as compared with the RVF. In contrast, display of printed response alternatives in the RVF elicited a greater percentage of McGurk responses than display in the LVF. Visual field differences were absent in a group of 15 left-handed subjects. These results suggest that in right-handers, the two hemispheres may make distinct contributions to the McGurk effect. The callosotomy patient demonstrated reliable McGurk effects, but at a lower rate than the normal subjects and the epileptic control subjects. These data support the view that both the right and left hemisphere can make significant contributions to the McGurk effect.     

Human resource planning: Challenges for industrial/organizational psychologists.

Human resource planning has traditionally been used by organizations to ensure that the right person is in the right job at the right time. Under past conditions of relative environmental certainty and stability, human resource planning focused on the short term and was dictated largely by line management concerns. Increasing environmental instability, demographic shifts, changes in technology, and heightened international competition are changing the need for and the nature of human resource planning in leading organizations. Planning is increasingly the product of the interaction between line management and planners. In addition, organizations are realizing that in order to adequately address human resource concerns, they must develop long-term as well as short-term solutions. As human resource planners involve themselves in more programs to serve the needs of the business, and even influence the direction of the business, they face new and increased responsibilities and challenges. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Glutamate currents in morphologically identified human dentate granule cells in temporal lobe epilepsy

Glutamate-receptor-mediated synaptic transmission was studied in morphologically identified hippocampal dentate granule cells (DGCs; n = 31) with the use of whole cell patch-clamp recording and intracellular injection of biocytin or Lucifer yellow in slices prepared from surgically removed medial temporal lobe specimens of epileptic patients (14 specimens from 14 patients). In the current-clamp recording, low-frequency stimulation of the perforant path generated depolarizing postsynaptic potentials that consisted of excitatory postsynaptic potentials and phase-inverted inhibitory postsynaptic potentials mediated by the gamma-aminobutyric acid-A (GABA(A)) receptor at a resting membrane potential of -62.7 +/- 2.0 (SE) mV. In the voltage-clamp recording, two glutamate conductances, a fast alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)-receptor-mediated excitatory postsynaptic current (EPSC; AMPA EPSC) and a slowly developing N-methyl-D-aspartate (NMDA)-receptor-mediated EPSC (NMDA EPSC), were isolated in the presence of a GABA(A) receptor antagonist. NMDA EPSCs showed a voltage-dependent increase in conductance with depolarization by exhibiting an N-shaped current-voltage relationship. The slope conductance of the NMDA EPSC ranged from 1.1 to 9.4 nS in 31 DGCs, reaching up to twice the size of the AMPA conductance. This widely varying size of the NMDA conductance resulted in the generation of double-peaked EPSCs and a nonlinear increase of the slope conductance of up to 37.5 nS with positive membrane potentials, which resembled "paroxysmal currents," in a subpopulation of the neurons. In contrast, AMPA EPSCs, which were isolated in the presence of an NMDA receptor antagonist (2-amino-5-phosphonovaleric acid), showed voltage-independent linear changes in the current-voltage relationship and were blocked by 6-cyano-7-nitroquinoxaline-2,3-dione. The AMPA conductance showed little variance, regardless of the size of the NMDA conductance of a given neuron. The average AMPA slope conductance was 5.28 +/- 0.65 (SE) nS in 31 human DGCs. This value was similar to AMPA EPSC conductances in normal rat DGCs (5.35 +/- 0.52 nS, mean +/- SE; n = 55). Dendritic morphology and spine density were quantified in the individual DGCs to assess epileptic pathology. Dendritic spine density showed an inverse correlation (r2 = 0.705) with a slower rise time and a longer half-width of the excitatory postsynaptic potentials mediated by the NMDA receptor. It is concluded that both AMPA and NMDA EPSCs contribute to human DGC synaptic transmission in epileptic hippocampus. However, a wide range of changes in the slope conductance of the NMDA EPSCs suggests that the NMDA-receptor-mediated conductance could be altered in human epileptic DGCs. These changes may influence the generation of chronic subthreshold epileptogenic synaptic activity and give rise to pathological excitation leading to epileptic seizures and dendritic pathology.     

Multiphasic renal CT: comparison of renal mass enhancement during the corticomedullary and nephrographic phases

We report a combined EEG-single-photon emission CT (SPECT) study on a patient with epileptic negative myoclonus (ENM). Clinically, the ENM was characterized by brief repetitive lapses in postural tone of the right upper extremity when the arms were held outstretched, whereas no movement effect was observed during rest. Ictal EEG showed repetitive left frontal spikes with a maximum at electrodes EC1 and F1. EMG silent periods lasting from 100 to 200 ms followed the onset of the EEG transients by a latency of 20 to 40 ms. The N20 component of median nerve somatosensory evoked potentials-representing a biological marker of the location of central fissure-showed a phase reversal between electrodes P3 and C1 and thus was located considerably posterior to the spike maximum. We obtained accurate anatomic reference of cerebral blood flow changes visible on SPECT by a special coregistration technique of MRI and SPECT. SPECT performed during ENM showed a marked regional hyperperfusion in the left middle frontal gyrus and a less pronounced increase in tracer uptake in the left supramarginal gyrus. Our results suggest that ENM is generated by epileptic activity in the premotor area in the middle frontal gyrus corresponding to Brodmann's area 6.     

The clinical picture and electroencephalographic changes in patients with multifocal epilepsy depending on the location of the epileptic foci

As many 116 patients were examined for the clinical course and electroencephalographic changes as well as for the x-ray, CT and NMR-tomography data, on the basis of which different forms of multifocal epilepsy were distinguished: with unilateral epileptic foci (cortical and cortico-subcortical form), bitemporal and with multiple bilateral epileptic foci. The data provided make it possible to differentiate between multifocal epilepsy and generalized epilepsy and to perform surgical treatment using the optimal surgical intervention.     

Computational and numerical methods for bioelectric field problems

Fundamental problems in electrophysiology can be studied by computationally modeling and simulating the associated microscopic and macroscopic bioelectric fields. To study such fields computationally, researchers have developed a variety of numerical and computational techniques. Advances in computer architectures have allowed researchers to model increasingly complex biophysical systems. Modeling such systems requires a researcher to apply a wide variety of computational and numerical methods to describe the underlying physics and physiology of the associated three-dimensional geometries. Issues naturally arise as to the accuracy and efficiency of such methods. In this paper we review computational and numerical methods of solving bioelectric field problems. The motivating applications represent a class of bioelectric field problems that arise in electrocardiography and electroencephalography.     

Comparison of angiomyofibroblastoma and aggressive angiomyxoma in both sexes: four cases composed of bimodal CD34 and factor XIIIa positive dendritic cell subsets

Aggressive angiomyxoma (AA) is a distinctive, locally aggressive, fibromyxoid tumor of the pelvic and genital soft tissues. AA is of unknown histogenesis but the cytologically bland spindled tumor cells, which surround characteristic variegated blood vessels, show fibroblastic or myofibroblastic features. AA may be related to angiomyofibroblastoma (AMF), another cytologically bland fibromyxoid genital spindle cell tumor with variable myoid differentiation that does not, as a rule, recur. Recently, CD34+ primitive fibroblasts and factor XIIIa+ dendritic histiocytes have been found in varying combination in many fibrovascular, fibrohistiocytic, and myxoid soft tissue tumors. Both cells belong to the microvascular unit, a tissue responsible for stromal repair and remodeling and angiogenesis. To determine if these ubiquitous stromal cells participate in the histogenesis of AA and AMF, we examined two scrotal tumors, one AA with multiple recurrences and one AMF, for the presence of CD34+ and FXIIIa+ dendritic cell subsets. For comparison, a vaginal AMF and a pararectal AA in a woman were included. We also studied actins and desmin to detect myofibroblastic differentiation, and, through double labeling studies, assessed hormone receptors and the cell cycle marker Ki 67 in the different cell subsets. The AA showed unusual cytologic atypia and was initially diagnosed as liposarcoma. It massively recurred four times over 12 years, the first time after seven years. The histologic appearance was fairly constant over the years. The scrotal AMF was a circumscribed 6 cm mass in a 37 year old man. In both cases, most tumor cells were wavy and fibrillar, spindled, stellate, or polygonal fibroblast-like CD34+ dendritic cells. Depending on the area examined, a 20-50% subset of dendritic cells showed both nuclear and cytoplasmic staining for FXIIIa. Actin+ cells were rare but vessels had actin+ myopericytes, although a small focus of the initial male AA was desmin positive. The recurring AA expressed androgen receptors and had Ki 67 index of 10-20% in "hot spots" of the primary and up to 30% in recurrent tumors. The scrotal AMF widely expressed androgen and progesterone receptors with focal estrogen receptor positivity and the Ki 67 index was 10%. Both CD34+ fibroblasts and FXIIIa+ histiocytes were present in the Ki 67+ cycling fraction in both the male AA and AMF and both cell types expressed androgen receptors. The female pararectal AA had more focal CD34 reactivity, particularly in perivascular fibroblasts and these cells were admixed with small FXIIIa+ cells. The vaginal AMF was strongly desmin+ and variably to weakly CD34+ with 20% FXIIIa+ dendritic cells and Ki 67 index of 2%. The vaginal AMF strongly expressed estrogen, progesterone, and androgen receptors. In conclusion our data suggest that at least some AA and AMF are myxoid fibrohistiocytic tumors composed of CD34+ fibroblasts and FXIIIa+ dendritic histiocytes. In our tumors, neoplastic CD34+ dendritic fibroblasts showed predominantly myxo-collagenous differentiation with prominent myofibroblastic differentiation in only one desmin+ vaginal AMF. Our results support the notion that AMF and AA are part of a morphologic and histogenetic continuum of myxofibrous and myoid tumors that may arise due to interactions between microvascular CD34+ fibroblasts and FXIIIa+ histiocytes. CD34 and FXIIIa reactivity may be underappreciated in these tumors and is more important when considered histogenetically and biologically rather than in classifying individual neoplasms. Hormonal stimulation of proliferating pelvico-gential microvascular dendritic cells appears to play a role in the morphogenesis of both tumors.     

Group B streptococcus infection rate unchanged by gestational diabetes

The role of electrolysis products, including protons, hydroxyl ions, reactive oxygen intermediates, oxygen, hydrogen, and heat, in mediating electrical enhancement of killing of Pseudomonas aeruginosa biofilms by tobramycin (the bioelectric effect) was investigated. The log reduction in biofilm viable cell numbers compared to the numbers for the untreated positive control effected by antibiotic increased from 2.88 in the absence of electric current to 5.58 in the presence of electric current. No enhancement of antibiotic efficacy was observed when the buffer composition was changed to simulate the reduced pH that prevails during electrolysis. Neither did stabilization of the pH during electrical treatment by increasing the buffer strength eliminate the bioelectric effect. The temperature increase measured in our experiments, less than 0.2 degree C, was far too small to account for the greatly enhanced antibiotic efficacy. The addition of sodium thiosulfate, an agent capable of rapidly neutralizing reactive oxygen intermediates, did not abolish electrical enhancement of killing. The bioelectric effect persisted when all of the ionic constituents of the medium except the two phosphate buffer components were omitted. This renders the possibility of electrochemical generation of an inhibitory ion, such as nitrite from nitrate, an unlikely explanation for electrical enhancement. The one plausible explanation for the bioelectric effect revealed by this study was the increased delivery of oxygen to the biofilm due to electrolysis. When gaseous oxygen was bubbled into the treatment chamber during exposure to tobramycin (without electric current), a 1.8-log enhancement of killing resulted. The enhancement of antibiotic killing by oxygen was not due simply to physical disturbances caused by sparging the gas because similar delivery of gaseous hydrogen caused no enhancement whatsoever.     

Managing within a culturally diverse environment

This paper attempts to elucidate whether common (nonspecific) brain mechanisms are responsible for seizures of epileptic and nonepileptic origin. A comparative study of the following 4 paroxysmal disorders--partial epileptic seizures, paroxysmal dystonia, pseudoseizures and panic attacks was performed. Spontaneous (EEG-mapping) and evoked (contingent negative variation-CNV) bioelectrical activity was measures in all patients several times during interictal periods and after 24-hour sleep deprivation. The main common neurophysiological features of these types of paroxysmal disorders were the increased total power of spontaneous electrical activity, an asymmetric increase of theta-EEC power in the right hemisphere, an increase in total amplitude of CNV. Readiness of the brain for the development of the paroxysms was characterized by dynamic increases of the above parameters of spontaneous and evoked bioelectrical activity.     

MR findings of hypoxic damage of the bilateral striate cortices: a case report

The frequency of accessory mental foramina (AMF) was studied in four population groups: 20th century Asian Indians, African Americans and American Whites, and Pre-Columbian Nazca Indians. AMF were found less frequently in the American White and Asian Indian populations than in the other groups (American White, 1.4%; Asian Indian, 1.5%; African American, 5.7% and Nazca, 9.0%). The incidence of AMFs did not differ significantly between right- and left-hand sides. In certain ethnic groups, i.e., African American, AMF may occur more often in males. Additional studies with larger samples are needed to show whether AMFs are more common in males.