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BACKGROUND: Previous reports have indicated that ketamine anesthesia may produce significant improvement if not complete recovery of patients with complex regional pain syndrome (CRPS). AIMS: Here we report on a patient who had CRPS affecting mainly the right side of her body who underwent functional magnetic resonance imaging (fMRI) scans prior to and in the months following apparent successful treatment with anesthetic doses of ketamine. MATERIALS AND METHODS: The patient underwent two imaging sessions: one during her pain state (CRPS+) and 1 month after her ketamine treatment in her pain-free state (CRPS-). Both spontaneous and evoked (brush, cold, and heat) pain scores decreased from 7­9/10 on a visual analog scale prior to the treatment to 0­1 immediately following and for months after the treatment. For each imaging session, the identical mechanical (brush) and thermal (cold and heat) stimuli were applied to the same location (the skin of the dorsum of the right hand). RESULTS: Comparison of CRPS+ vs CRPS- for the three stimuli showed significant changes throughout the cerebral cortex (frontal, parietal, temporal, cingulate, and hippocampus), in subcortical regions such as caudate nucleus, and in the cerebellum. In addition, resting state network analysis showed a reversal of brain network state, and the recovered state paralleled specific default networks in healthy volunteers. DISCUSSION: The observed changes in brain response to evoked stimuli provide a readout for the subjective response. CONCLUSION: Future studies of brain function in these patients may provide novel insight into brain plasticity in response to this treatment for chronic pain.

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Populations in fragmented landscapes experience reduced gene flow, lose genetic diversity over time and ultimately face greater extinction risk. Improving connectivity in fragmented landscapes is now a major focus of conservation biology. Designing effective wildlife corridors for this purpose, however, requires an accurate understanding of how landscapes shape gene flow. The preponderance of landscape resistance models generated to date, however, is subjectively parameterized based on expert opinion or proxy measures of gene flow. While the relatively few studies that use genetic data are more rigorous, frameworks they employ frequently yield models only weakly related to the observed patterns of genetic isolation. Here, we describe a new framework that uses expert opinion as a starting point. By systematically varying each model parameter, we sought to either validate the assumptions of expert opinion, or identify a peak of support for a new model more highly related to genetic isolation. This approach also accounts for interactions between variables, allows for nonlinear responses and excludes variables that reduce model performance. We demonstrate its utility on a population of mountain goats inhabiting a fragmented landscape in the Cascade Range, Washington.

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Complex regional pain syndrome (CRPS) in paediatric patients is clinically distinct from the adult condition in which there is often complete resolution of its signs and symptoms within several months to a few years. The ability to compare the symptomatic and asymptomatic condition in the same individuals makes this population interesting for the investigation of mechanisms underlying pain and other symptoms of CRPS. We used fMRI to evaluate CNS activation in paediatric patients (9-18 years) with CRPS affecting the lower extremity. Each patient underwent two scanning sessions: once during an active period of pain (CRPS(+)), and once after symptomatic recovery (CRPS(-)). In each session, mechanical (brush) and thermal (cold) stimuli were applied to the affected region of the involved limb and the corresponding mirror region of the unaffected limb. Two fundamental fMRI analyses were performed: (i) within-group analysis for CRPS(+) state and CRPS(-) state for brush and cold for the affected and unaffected limbs in each case; (ii) between-group (contrast) analysis for activations in affected and unaffected limbs in CRPS or post-CRPS states. We found: (i) in the CRPS(+) state, stimuli that evoked mechanical or cold allodynia produced patterns of CNS activation similar to those reported in adult CRPS; (ii) in the CRPS(+) state, stimuli that evoked mechanical or cold allodynia produced significant decreases in BOLD signal, suggesting pain-induced activation of endogenous pain modulatory systems; (iii) cold- or brush-induced activations in regions such as the basal ganglia and parietal lobe may explain some CNS-related symptoms in CRPS, including movement disorders and hemineglect/inattention; (iv) in the CRPS(-) state, significant activation differences persisted despite nearly complete elimination of evoked pain; (v) although non-noxious stimuli to the unaffected limb were perceived as equivalent in CRPS(+) and CRPS(-) states, the same stimulus produced different patterns of activation in the two states, suggesting that the 'CRPS brain' responds differently to normal stimuli applied to unaffected regions. Our results suggest significant changes in CNS circuitry in patients with CRPS.

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By using arrays of nanowires with intentionally broken symmetry, we were able to detect microwaves up to 110 GHz at room temperature. This is, to the best of our knowledge, the highest speed that has been demonstrated in different types of novel electronic nanostructures to date. Our experiments showed a rather stable detection sensitivity over a broad frequency range from 100 MHz to 110 GHz. The novel working principle enabled the nanowires to detect microwaves efficiently without a dc bias. In principle, the need for only one high-resolution lithography step and the planar architecture allow an arbitrary number of nanowires to be made by folding a linear array as many times as required over a large area, for example, a whole wafer. Our experiment on 18 parallel nanowires showed a sensitivity of approximately 75 mV dc output/mW of nominal input power of the 110 GHz signal, even though only about 0.4% of the rf power was effectively applied to the structure because of an impedance mismatch. Because this array of nanowires operates simultaneously, low detection noise was achieved, allowing us to detect -25 dBm 110 GHz microwaves at zero bias with a standard setup.

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Rapid processing of histopathologic material is becoming increasingly desirable to fulfill the needs of clinicians treating acutely ill patients. Traditional techniques for rapid processing of paraffin-embedded tissues require 4 to 5 hours, delaying treatment for some critically ill patients and requiring additional shifts of technologists in the laboratory. Microwave processing further shortens this time, allowing even more rapid histopathologic diagnosis. Few data exist comparing quality of microwave-processed tissue with that processed by more traditional techniques. We randomly selected 158 paired specimens from 111 patients. One member of the pair was processed routinely overnight, while the other was processed by the rapid microwave technique. The slides then were compared for quality of histologic preparation in a blinded fashion by 2 pathologists. Eight routinely processed specimens were judged as suboptimal, while 6 microwave-processed specimens were judged as suboptimal and 1 was considered unsatisfactory for evaluation. In the remaining cases, the material obtained by the 2 techniques was considered of identical quality. Microwave processing considerably shortens the preparation time for permanent histologic sections without a demonstrable decrease in section quality or "readability."

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The primary objective of this study was to compare the antihypertensive efficacy and safety of intravenously administered nicardipine with that of intravenous nitroprusside (SNP) in patients with severe hypertension. The study was conducted in 121 patients with severe hypertension (diastolic blood pressure [BP] > 120 mm Hg, or systolic BP > 200 mm Hg). Patients were randomized to receive intravenous nicardipine or SNP. Drugs were administered according to a predetermined dosing schedule for a 10 to 12 h period. Sixty-one patients were randomized to intravenous nicardipine and 60 to SNP. Pretreatment BP values for the nicardipine and SNP groups were 217/128 mm Hg and 219/128 mm Hg, respectively. Therapeutic response (diastolic BP < 100 mm Hg, or a decrease of > 15 mm Hg; systolic BP < 180 mm Hg, or a decrease of > 20 mm Hg) was achieved in 98% (60/61) of patients treated with nicardipine and 93% (56/60) of patients treated with SNP. The mean decreases in systolic and diastolic BP were 61 mm Hg and 40 mm Hg after 4 h of nicardipine, and 59 mm Hg and 38 mm Hg after 4 h of SNP. The mean increases in heart rate also were similar in both groups (nicardipine, 12 beats/min; SNP 10 beats/min). The mean numbers of dose adjustments per hour required to maintain the BP reductions were lower (P < .01) in the nicardipine-treated patients (0.5 +/- 0.1 times per hour) than in the SNP-treated patients (1.5 +/- 0.2 times per hour).(ABSTRACT TRUNCATED AT 250 WORDS)

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Enoximone is an investigational cardiotonic agent with positive inotropic and vasodilatory properties. In this protocol the effects of enoximone on parameters of renal function in patients (n = 14) with New York Heart Association class II or III congestive heart failure were determined after intravenous (IV) treatment (2 mg/kg) and after chronic oral administration (150 mg t.i.d.), either alone or with added furosemide (40 mg b.i.d.). Glomerular filtration rate (GFR), effective renal plasma flow (ERPF), filtration fraction, mean arterial pressure (MAP), renal blood flow (RBF), and renal vascular resistance (RVR) were determined each time. Plasma volume (PV) was determined at baseline and after oral enoximone and after oral enoximone plus furosemide. Significant reductions in GFR (18%) and ERPF (20%) were observed after IV treatment but not after oral treatment with or without furosemide. MAP also was lowered significantly by 14% after IV administration but not after oral treatments. PV after oral enoximone plus furosemide was reduced significantly (31%) compared with baseline. These results demonstrate that enoximone produces acute reductions in GFR and ERPF when given intravenously but has no effect on parameters of renal function when given orally, either alone or with furosemide.

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Forty-seven male subjects were randomly assigned to 4 different groups. Three groups of 10 subjects trained three times a week with a modified contract-relax (CR) method for improving muscle flexibility. Seventeen subjects trained during the same time with a traditional ballistic stretch (BS) method. After 30 days (14 training sessions) the latter group switched over to the CR method. The results showed that the CR method was significantly better than the BS method for improving muscle flexibility in the four different, bilateral muscle groups studied. After the initial 30 days the three groups of 10 subjects trained one, three, and five times a week, respectively, for another 30 days. The results showed that once a week was enough to maintain improved flexibility, while three and five times a week increased it further. The former BS group improved muscle flexibility between the 30th and 60th day, as expected from the results of the initial 30 days with the three CR groups, when training with the CR method three times a week.

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