Severe human granulocytic anaplasmosis transmitted by blood transfusion

A 36-year-old woman acquired severe human granulocytic anaplasmosis after blood transfusion following a cesarean section. Although intensive treatment with mechanical ventilation was needed, the patient had an excellent recovery. Disease caused by Anaplasma phagocytophilum infection was confirmed in 1 blood donor and in the transfusion recipient.     

Dopamine receptors of the monkey anterior pituitary in various endocrine states

The anterior pituitary of adult Macaca fascicularis monkeys was removed when they were killed and the potent dopamine (DA) antagonist [3H]spiperone was used to label DA receptors. Saturation isotherms of [3H]piperone binding indicated a dissociation constant of 0.09 nM and maximal sites of 170 fmol/mg assay protein (n = 2). Competition studies validated the hypothesis that [3H]spiperone labeled DA receptors; the order of potency of 12 compounds was appropriate for a dopaminergic interaction and was similar to the order found in the anterior pituitary of other mammals. A concentration of [3H]spiperone that would label 90% of the specific binding sites (0.76 nM) was used to estimate the total DA receptor activity in the anterior pituitary of individual monkeys. [3H]spiperone binding in pregnant monkeys was greater than the binding in ovariectomized and lactating females or intact males (P less than 0.05 or 0.01). The postpartum lactating group contained more [3H]spiperone binding activity than the cycling group (P less than 0.05). Determination of the serum concentrations of PRL, estradiol, testosterone, progesterone, and dehydroepiandrosterone confirmed the predicted hormonal status of the individual monkeys at the time of sacrifice. Because DA is a PRL inhibitory hormone, it was of interest that the serum PRL concentration was positively correlated with the degree of [3H]spiperone binding (r2 = 0.74). This observation, combined with the known hypertrophy and/or hyperplasia of the mammotroph during pregnancy, supports the hypothesis that the DA receptor is associated with the PRL cell of the anterior pituitary.     

Changes in fetal rhesus monkey plasma dehydroepiandrosterone sulfate: relationship to gestational age, adrenal weight and preterm delivery

These studies were performed to assess the concentrations of dehydroepiandrosterone sulfate (DHAS) in the rhesus monkey fetal circulation from midgestation through the neonatal period, to determine the relation between changes in fetal adrenal size and DHAS levels both during gestation and after surgical stress, and to explore possible relations between changes in the concentration of DHAS in the fetal circulation and the initiation of labor. When plasma DHAS was quantified in cord blood and in serial samples from chronically catheterized rhesus monkey fetuses, a significant increase in plasma DHAS concentration occurred after 150 days gestational age (404 +/- 37 vs. 1093 +/- 159 ng/ml), and an additional increase was found after 159 days (2246 +/- 712 ng/ml). A diurnal change in fetal plasma DHAS occurred in chronically catheterized fetuses, with evening samples having higher values than morning samples. Further, there was an increase in plasma DHAS concentrations in the 4-5 days after fetal surgery. A significant increase in fetal plasma DHAS concentration occurred in the newborn rhesus monkey. Although plasma DHAS concentrations remained significantly higher than in the late gestation fetus, they decreased by approximately half within the first 2 weeks of life. A close correlation existed between fetal plasma DHAS and fetal adrenal weight in control fetuses delivered by hysterotomy and fetuses that were delivered 5 days after fetal surgery. Adrenal weights in the latter were significantly higher than those in comparably aged fetuses delivered by hysterotomy that had not undergone the stress of fetal surgery. The possible relationship between the increase in plasma DHAS and the initiation of labor was studied by monitoring the changes in daily morning DHAS concentrations in long term catheterized fetuses and comparing these values to the mean cross-sectional DHAS values corresponding to that gestational age. In all but one case, the values of DHAS, although they increased preceding delivery, were still within the range found in fetuses of the same gestational age that were not in labor. These data indicate that increases in DHAS are intimately related to parallel increases in fetal adrenal weight, that there are striking increases in DHAS levels near the end of gestation, that an increase in DHAS is a component of the fetal response to surgical stress, and that there is no immediately apparent, direct relationship between fetal DHAS and preterm delivery.     

Acute stress reactivity from contested dominance in dominant and submissive males

We examined the cardiovascular and testosterone responses of dominant and submissive males to an interpersonal challenge of dominance status. Twenty college-aged students rated their dominance to predefined reference groups and engaged in a debate against a trained technician. Throughout the task, they were continuously given false feedback regarding biochemical substances in the plasma that purportedly covaried with dominance. Covariance analyses revealed that the task created greater heart rate reactivity and lower testosterone levels on the part of submissive subjects when contrasted with those scoring high in self-reported dominance. Interpretation of these data emphasizes the importance of an interactionist perspective in research dealing with acute stress reactivity.     

Gripping-force identification using EEG and phase-demodulation approach

In this paper we investigate the fuzzy identification of brain-code during simple gripping-force control tasks. Since the synchronized oscillatory activity and the phase dynamics between the brain areas are two important mechanisms in the brain’s function and information transfer, we decided to examine whether it is possible to extract the encoded information from the EEG signals using the phase-demodulation approach. The EEG was measured during the performance of different visuomotor tasks and the information we were trying to decode was the gripping force as applied by the subjects. The study revealed that it is possible, by using simple beta-rhythm filtering, phase demodulation, principal component analysis and a fuzzy model, to estimate the gripping-force response by using EEG signals as the inputs for the proposed model. The presented study has shown that even though EEG signals represent a superposition of all the active neurons, it is still possible to decode some information about the current activity of the brain centers. Furthermore, the cross-validation showed that the information about the gripping force is encoded in a very similar way for all the examined subjects. Thus, the phase shifts of the EEG signals seem to have a key role during activity and information transfer in the brain, while the phase-demodulation method proved to be a crucial step in the signal processing.     

Anabolic steroids and aggressive behavior in cynomolgus monkeys

An animal model was employed to examine the effect of testosterone on aggressive behavior patterns. Ten cynomolgus monkeys were assigned to either an experimental or a control group and given biweekly injections; the experimental group received testosterone propionate, and the controls a sham solution. Prior to and upon the completion of an 8-week treatment period, behavioral observations were conducted. Although the administration of testosterone resulted in a significant increase in aggression, more important was the finding that changes in behavior were mediated by social status; that is, the incidence of both contact and noncontact aggression in dominant monkeys was far greater than the frequency of these behaviors in subordinate monkeys. These data are discussed in terms of the potential role of anabolic steroids as a risk factor in cardiovascular disease.Research described here was supported, in part, by grants from the National Heart, Lung and Blood Institute (HL14164, HL72978, HL30675).     

Virtual environment for lower-extremities training

This study proposed virtual reality (VR) as a modality of lower-extremities training. A kinematic model of a human body and a corresponding virtual figure were developed, in order to visualize the movements of the subject in a real-time virtual environment on a large display, which represented a virtual mirror. An optical system with active markers was used to assess the movements of a training subject. A preliminary investigation was conducted with a group of healthy male subjects, who performed the stepping-in-place test by tracking the movements of the reference virtual figure, which represented a virtual instructor. Both figures were shown in the virtual mirror at the same time from the desired angle of view. Four stepping tasks featuring different cadences and hip angles were performed, with difficulty levels ranging from easy to demanding. The results obtained included basic kinematic and temporal parameters, which provided quantitative measures of a subject's adaptation to the virtual training environment, and thereby justifying the feasibility of the virtual mirror as a useful system in lower-extremities training applications.