Heated humidified high-flow nasal oxygen prevents intraoperative body temperature decrease in non-intubated thoracoscopy.

PURPOSE: In patients receiving non-intubated video-assisted thoracic surgery (NIVATS), transnasal humidified rapid-insufflation ventilatory exchange (THRIVE) has been applied instead of oxygen mask for better oxygenation. However, the THRIVE effects on intraoperative temperature decrease have not been investigated. METHODS: Pre- and postoperative temperatures, measured by an infrared tympanic ear thermometer, taken before sending patients to the operation room and immediately upon their arrival in the postoperative anesthesia unit, were collected from medical records of patients who received NIVATS either with oxygen mask or THRIVE. Intraoperative temperature decrease, calculated by preoperative temperature minus postoperative temperature, was compared between different groups. Multiple linear regression analysis was performed to determine factors associated with intraoperative temperature decrease. RESULTS: Records of 256 adult patients with forced-air warming were retrospectively analyzed. 172 patients of them received THRIVE and 84 patients received oxygen mask. Preoperative temperatures were comparable between groups (THRIVE: 36.25 ± 0.46 °C; mask: 36.30 ± 0.39 °C, p = 0.43). Postoperative temperatures were significantly higher in patients using THRIVE than those using oxygen masks (36.05 ± 0.59 vs 35.87 ± 0.62 °C, p = 0.025). Significantly less intraoperative temperature decrease was shown in THRIVE group (THRIVE: 0.20 ± 0.69 °C; mask: 0.43 ± 0.69 °C, p = 0.04). According to the multiple linear regression analysis, significant temperature decrease was associated with the advanced age (ßage = 0.01) but not the anesthetic duration. Using THRIVE was correlated with significantly less body temperature decrease (ßTRIVE = - 0.24). CONCLUSIONS: THRIVE effectively prevents intraoperative temperature decrease during NIVATS, especially in old patients.

Cone beam CT for determining breast cancer margin: an initial experience and its comparison with mammography and specimen radiograph.

PURPOSE: To assess the ability of cone beam CT (CBCT) in determining the breast cancer margin using, to compare the results with mammography and specimen radiography, and to explore the clinical potential of CBCT for breast imaging. METHODS: Specimens of 46 breast cancer patients were imaged by using a prototype CBCT system. Each patient underwent mammography, CBCT and X-ray of breast surgical specimen within 6 months. Images of mammography, breast surgical specimen radiography and CBCT were evaluated by an experienced radiologist. Indicators, such as: morphology, glitch, density, invasion, structural distortion and calcification, were observed. RESULT: There was no significant difference of the calcification, glitch and morphology among three methods. However, there was significant difference in indicators of breast tumor invasion among three methods. There was statistical significance in detecting invasions of breast cancer cells in peripheral tissues among three methods. CONCLUSION: CBCT shows no superiority over mammography and specimen radiography in determining tumor's outline and detecting calcification. On the other hand, CBCT demonstrates its advantage in determining the 3 dimensional position of a lesion which could be a potential clinical application in future practices of breast imaging.

The influence of autonomic interventions on the sleep-wake-related changes in gastric myoelectrical activity in rats.

BACKGROUND: Significant changes in autonomic activity occur at sleep-wake transitions and constitute an ideal setting for investigating the modulatory role of the autonomic nervous system on gastric myoelectrical activity (GMA). METHODS: Using continuous power spectral analysis of electroencephalogram, electromyogram, and electrogastromyogram (EGMG) data from freely moving rats that had undergone chemical sympathetomy and/or truncal vagotomy, sleep-wake-related fluctuations in GMA were compared among the intervention groups. KEY RESULTS: The pattern and extent of fluctuations in EGMG power across the sleep-wake states was blunted most significantly in rats undergoing both chemical sympathectomy and truncal vagotomy. The effect of these interventions also varied with respect to the transition between different sleep-wake states. The most prominent influences were observed between active waking and quiet sleep and between paradoxical sleep and quiet sleep. CONCLUSIONS & INFERENCES: The sleep-wake-related fluctuations in EGMG power are a result of joint contributions from both sympathetic and vagal innervation. Vagotomy mainly resulted in a reduction in EGMG power, while the role of sympathetic innervation was unveiled by vagotomy and this was reflected most obviously in the extent of the fluctuations in EGMG power.

Ovalbumin sensitizes vagal pulmonary C-fiber afferents in Brown Norway rats.

Sensitization of vagal lung C fibers has been postulated to contribute to the development of asthma, but support for this notion is still lacking. We investigated the characteristics and function of pulmonary C fibers (PCFs) in ovalbumin (OVA)-sensitized Brown Norway rats, an established animal model of asthma. Rats were sensitized with intraperitoneal injection of OVA or were treated with saline (control). In study 1, with the use of open-chest and artificially ventilated rats, inhalation of 5% OVA aerosol evoked an augmented increase in total lung resistance in the OVA-sensitized rats, compared with the control rats. Bilateral vagotomy or subcutaneous pretreatment with a high-dose of capsaicin for blocking of C-fiber function equally attenuated this augmented total lung resistance response, suggesting the involvement of PCFs. In study 2, with the use of anesthetized, spontaneously breathing rats, right atrial injection of capsaicin (1 microg/kg; a PCF stimulant) evoked an augmented apneic response in the OVA-sensitized rats, compared with the control rats. In study 3, with the use of open-chest, paralyzed, and artificially ventilated rats, the afferent PCF responses to right atrial injection of capsaicin (0.5 and 1.0 microg/kg), phenylbiguanide (8 microg/kg; a PCF stimulant), or adenosine (0.2 mg/kg; a PCF stimulant) were enhanced in the OVA-sensitized rats, compared with the control rats. However, the baseline activities of PCFs and their afferent responses to mechanical stimulation by lung hyperinflation in the OVA-sensitized and control rats were comparable. Our results suggested that OVA-sensitized Brown Norway rats possess sensitized vagal PCFs, which may participate in the development of the airway hyperreactivity observed in these animals.

Protein quality of anchovy, mackerel and canned sardine samples.

The protein nutritive value of anchovy, mackerel and canned sardine samples together with casein as a reference formulation were evaluated. Proximate composition, protein quality and protein digestibility were determined. Procedures for evaluation included Protein Efficiency Ratio (PER) using the rat bioassay and in vivo Apparent Digestibility (AD). Rats fed with canned sardine diet had the highest mean body weight (154.8±12.28g) while rats fed with anchovy diet had the lowest mean body weight (145.27±15.89g) with significant differences between all the groups. Mean body weight of rats fed with selected fish diet was higher compared to rats fed with casein diet. For PER value, canned sardine has the highest value (2.48), followed by anchovy (2.46) and mackerel (2.34). PER value for all selected fish is lower than that for casein (3.14). Mackerel had the highest value of in vivo AD (96.99%), followed by casein (96.96%), canned sardine (96.88%) and anchovy (91.29%). In conclusion, among the types of fish compared, sardine had the highest protein quality while mackerel showed the highest digestibility.

Protein quality of anchovy, mackerel and canned sardine samples

The protein nutritive value of anchovy, mackerel and canned sardine samples together with casein as a reference formulation were evaluated. Proximate composition, protein quality and protein digestibility were determined. Procedures for evaluation included Protein Efficiency Ratio (PER) using the rat bioassay and in vivo Apparent Digestibility (AD). Rats fed with canned sardine diet had the highest mean body weight (154.8±12.28g) while rats fed with anchovy diet had the lowest mean body weight (145.27±15.89g) with significant differences between all the groups. Mean body weight of rats fed with selected fish diet was higher compared to rats fed with casein diet. For PER value, canned sardine has the highest value (2.48), followed by anchovy (2.46) and mackerel (2.34). PER value for all selected fish is lower than that for casein (3.14). Mackerel had the highest value of in vivo AD (96.99%), followed by casein (96.96%), canned sardine (96.88%) and anchovy (91.29%). In conclusion, among the types of fish compared, sardine had the highest protein quality while mackerel showed the highest digestibility.

Enhanced sympathetic outflow and decreased baroreflex sensitivity are associated with intermittent hypoxia-induced systemic hypertension in conscious rats.

Long-term exposure to intermittent hypoxia (IH), such as that occurring in association with sleep apnea, may result in systemic hypertension; however, the time course changes in arterial pressure, autonomic functions, and baroreflex sensitivity are still unclear. We investigated the changes in cardiovascular neural regulations during the development of chronic IH-induced hypertension in rats. Sprague-Dawley rats were exposed to repetitive 1.25-min cycles (30 s of N2+45 s of 21% O2) of IH or room air (RA) for 6 h/day during light phase (10 AM-4 PM) for 30 days. Arterial pressure was measured daily using the telemetry system during RA breathing. The mean arterial pressure (MAP) and interpulse interval (PPI) signals were then used to assess the autonomic functions and spontaneous baroreflex sensitivity by auto- and cross-spectral analysis, respectively. Stable MAP, low-frequency power of MAP (BLF), and low-frequency power (LF)-to-high frequency power (HF) ratio of PPI (LF/HF) were significantly higher in IH-exposed rats, compared with those of RA-exposed rats. Elevation of the MAP, BLF, LF/HF, and minute ventilation started 5 days after IH exposure and lasted until the end of the 30-day observation period. Additionally, IH-exposed rats had significant lower slope of MAP-PPI linear regression (under a successively descending and ascending) and magnitude of MAP-PPI transfer function (at frequency ranges of 0.06-0.6 Hz or 0.6-2.4 Hz) after IH exposure for 17 days. However, RA-exposed rats did not exhibit these changes. The results of this study indicate that chronic IH-induced hypertension is associated with a facilitation of cardiovascular sympathetic outflow and inhibition of baroreflex sensitivity in conscious rats.

Attenuation and immunogenicity in humans of a live dengue virus type-4 vaccine candidate with a 30 nucleotide deletion in its 3'-untranslated region.

The recombinant dengue virus type-4 vaccine candidate 2AA30 was attenuated in rhesus monkeys due to an engineered 30-nucleotide deletion in the 3'-untranslated region of the viral genome. A clinical trial to evaluate the safety and immunogenicity of a single dose of 2Adelta30 was conducted with 20 adult human volunteers. The vaccine candidate was well tolerated and did not cause systemic illness in any of the 20 volunteers. Viremia was detectable in 14 volunteers at a mean level of 1.6 log10 plaque-forming units/ml of serum, although all 20 volunteers seroconverted with a seven-fold or greater increase in serum neutralizing antibody titer on day 28 post-vaccination (mean titer = 1:580). A mild, asymptomatic, macular rash developed in 10 volunteers, and a transient elevation in the serum level of alanine aminotransferase was noted in five volunteers. The low level of reactogenicity and high degree of immunogenicity of this vaccine candidate warrant its further evaluation and its use to create chimeric vaccine viruses expressing the structural genes of dengue virus types 1, 2, and 3.

Successful resuscitation of patient with massive coronary air embolism occluding two vessels during coronary angiography--a case report.

Massive coronary air embolism is usually disastrous although successful resuscitation has been reported previously. To what extent a patient with coronary air embolism can be resuscitated is not known. The authors report a rare case of massive air embolism to the left coronary arteries and successful resuscitation by vigilantly maintaining an effective driving force to dissipate the air lock.

Endothelial dysfunction in type 2 diabetes mellitus subjects with peripheral artery disease.

We strived to characterize the endothelial function status in type 2 diabetic patients with peripheral artery disease which was detected by ankle-brachial index by utilizing high frequency ultrasounds. Predictors of endothelial dysfunction were investigated. We chose 23 type 2 diabetic patients had ankle-brachial index <0.97 (0.15-0.95; mean=0.74+/-0.20), 31 diabetic patients had ankle-brachial index >/=1.0 and 28 non-diabetic subjects for study. Older age, a longer duration of diabetes, higher systolic blood pressure, higher prevalence of history of hypertension were observed in patients with peripheral vascular disease. Type 2 diabetic patients showed impaired flow-mediated dilatation than non-diabetic and it showed more impaired in patients with peripheral vascular disease. Nitroglyerin-induced dilatation showed a trend of impairment in patients with peripheral vascular disease but did not reach statistical significance. Age (r=-0.259, P=0.019), baseline brachial artery diameter (r=-0.321, P=0.003), ankle-brachial index (r=0.259, P=0.002) and hypertension history (P=0.01) were significantly associated with flow-mediated dilatation. However, after adjusting for age, only baseline diameter and ankle-brachial index were independent predictors of flow-mediated dilatation. In conclusion, we demonstrated flow-mediated dilatation was impaired in type 2 diabetic patients and it was further impaired in patients with peripheral vascular disease. Nitroglycerin-induced dilatation showed a trend of impairment but did not reach statistical significance.

Immunization of rhesus monkeys with a recombinant of modified vaccinia virus Ankara expressing a truncated envelope glycoprotein of dengue type 2 virus induced resistance to dengue type 2 virus challenge.

Dengue epidemics increasingly pose a public health problem in most countries of the tropical and subtropical areas. Despite decades of research, development of a safe and effective live dengue virus vaccine is still at the experimental stage. To explore an alternative vaccine strategy, we employed the highly attenuated, replication-deficient modified vaccinia Ankara (MVA) as a vector to construct recombinants for expression of the major envelope glycoprotein of one or more dengue virus serotypes. MVA recombinants expressing the highly immunogenic C-terminally truncated dengue type 2 virus (DEN2) or dengue type 4 virus (DEN4) envelope protein (E), approx. 80% of the full-length, were evaluated for their protective immunity in animal models. Each of these recombinants elicited an elevated antibody response to DEN2 or DEN4 E in mice following the booster inoculation, as detected by radio-immunoprecipitation. Recombinant MVA-DEN2 80%E, but not MVA-DEN4 80%E, induced a neutralizing antibody response. The MVA-DEN2 80%E recombinant was chosen to further evaluate its ability to induce resistance to wild type DEN2 challenge in monkeys. Monkeys immunized twice with recombinant MVA-DEN2 80%E developed a low to moderate antibody response and were partially protected against DEN2 challenge, as determined by the viremia pattern. Importantly, the subsequent study showed that all four monkeys immunized with the recombinant in a three dose schedule developed an increased level of antibodies and were completely protected against DEN2 challenge. The potential efficacy of recombinant MVA-DEN2 80%E to protect primates against dengue infection suggests that construction and evaluation of MVA recombinants expressing other serotypes of dengue virus E for use in a tetravalent vaccine strategy might be warranted.

Isolation of an IgG monoclonal anti-dnaJ antibody from an immunoglobulin combinatorial library from a patient with rheumatoid arthritis.

OBJECTIVE: Previously, we showed that rheumatoid arthritis (RA) had both antibodies and T cells specific for the QKRAA-encompassing Escherichia coli dnaJ protein. These findings suggest that the bacteria induced anti-dnaJ responses may cross react with the human homolog of bacterial dnaJ in the joint, resulting in tissue damage. METHODS: We used the combinatorial library technique to isolate and characterize an IgG monoclonal anti-dnaJ antibody (designated CG1) from the blood of a patient with RA. RESULTS: Sequence analysis of CG1 revealed that its heavy and light chain V regions were respectively most homologous to the 3d279d VH4 and the O18 Vk1 genes. Interestingly, 3d279d is frequently expressed by B cells stimulated with staphylococcal enterotoxin; and O18 is the main gene employed by the Vk1 IgG antibodies against Haemophilus influenzae. CONCLUSION: The combinatorial immunoglobulin library method represents an interesting model of how to approach the isolation and characterization of antibody-like reagents in the elucidation of autoantigens in RA.

Evaluation of molecular strategies to develop a live dengue vaccine.

BACKGROUND: Millions of individuals are estimated to become infected with dengue virus each year, particularly in tropical and subtropical regions. Mortality is low but infection can lead to a severe form of dengue, characterised by haemorrhage and shock. A safe and effective vaccine against dengue is still not available. OBJECTIVE: To use the successful construction of dengue type 4 virus (DEN4) cDNA, which yields infectious RNA transcripts, to provide a new approach to the development of safe and effective dengue vaccines. STUDY DESIGN: The 3' and 5' noncoding (NC) regions of the genome were targeted to construct DEN4 deletion mutants, because the sequences in these regions are thought to play an important role in the regulation of viral replication. DEN4 cDNA was also employed to construct a viable chimeric virus with dengue type 1, 2 or 3 antigenicity, by substitution of heterotypic structural protein genes. RESULTS: Most viable mutants, recovered from the cDNA constructs, were partially restricted for growth in simian cells as analysed by plaque morphology assay and viral yield analysis. Several 3' NC deletion mutants which exhibited a range of growth restriction in cell culture were further evaluated for infectivity and immunogenicity in rhesus monkeys. Occurrence and duration of viraemia were reduced for these deletion mutants, compared to the wild type DEN4. Analysis of antibody response to infection in rhesus monkeys also indicated that some of these mutants were attenuated. These DEN4 deletion mutants represent promising live dengue vaccine candidates that merit further clinical evaluation. Chimera DEN1/DEN4 or DEN2/DEN4 which expresses DEN1 or DEN2 antigenicity were also used to infect monkeys. Most monkeys immunised with these chimeric viruses, singly or in combination, developed high titres of neutralising antibodies and were protected against homotypic wild type DEN1 or DEN2 challenge. CONCLUSIONS: DEN4 and its derived chimeric viruses of other three dengue serotype specificity, that contain appropriate attenuating mutations, have a potential use in a tetravalent live vaccine against dengue.

Inhibitory effect of inhaled wood smoke on the discharge of pulmonary stretch receptors in rats.

We investigated the inhibition of slowly adapting pulmonary stretch receptors (PSRs) by inhaled wood smoke. Impulses were recorded from PSRs in 68 anesthetized, open-chest, and artificially ventilated rats. Eighty-one of one hundred five PSRs were inhibited within one or two breaths when 6 ml of wood smoke were delivered into the lungs. As a group (n = 105), PSR activity significantly decreased from a baseline of 19.0 +/- 1.3 (SE) to a lowest level of 12.9 +/- 1.2 impulses/breath at the fourth or fifth breath after smoke delivery. This afferent inhibition usually persisted for 5-18 breaths. In contrast, smoke delivery did not affect transpulmonary pressure. Delivery of gas-phase smoke or a hypercapnic gas mixture containing CO2 at a concentration (15%) matching that in the smoke produced a nearly identical inhibition in the same PSRs (n = 10). This afferent inhibition was largely prevented by pretreatment with acetazolamide (an inhibitor of carbonic anhydrase; n = 10) but was not affected by pretreatment with the vehicle for acetazolamide (n = 8) or isoproterenol (a bronchodilator; n = 10). These results suggest that 1) an increase in H+ concentration resulting from hydration of CO2 in the smoke may be responsible for the inhibitory effect of wood smoke on the discharge of PSRs and 2) changes in lung mechanics are not the cause of this afferent inhibition.

Stimulation of pulmonary rapidly adapting receptors by inhaled wood smoke in rats.

1. The stimulation of pulmonary rapidly adapting receptors (RARs) by wood smoke was investigated. Impulses from seventy RARs were recorded in fifty-nine anaesthetized, open-chest and artificially ventilated rats; responses to delivery of 6 ml of wood smoke into the lungs were studied in sixty-one receptors whereas responses to histamine (10 or 100 microg kg-1, i.v.) were studied in the other nine. 2. Delivery of wood smoke stimulated fifty-two of the sixty-one RARs studied. When stimulated, an intense burst of discharge was evoked within 1 or 2 s of smoke delivery. This increased activity quickly peaked in 1-3 s (Delta = 15.8 +/- 1.6 impulses s-1; n = 61; mean +/- s.e.m.), then declined and yet remained at a level higher than the baseline activity. The mean duration of the stimulation was 25.1 +/- 2.7 s. In contrast, smoke delivery did not affect tracheal pressure. 3. Peak responses of RARs to wood smoke were partially reduced by removal of smoke particulates and were largely attenuated by pretreatment with dimethylthiourea (DMTU, a hydroxyl radical scavenger), indomethacin (Indo, a cyclo-oxygenase inhibitor), or both DMTU and Indo (DMTU + Indo). Conversely, the peak responses of RARs were not significantly affected by pretreatment with isoprenaline (a bronchodilator) or vehicle for these chemicals. Additionally, pretreatment with DMTU, Indo, or DMTU + Indo did not significantly alter the RAR sensitivity to mechanical stimulation (constant-pressure lung inflation; 20 cmH2O). 4. Of the nine RARs tested, six were stimulated by histamine and their sensitivity to this chemical irritant was not altered by pretreatment with DMTU + Indo. 5. The results suggest that both the particulates and gas phases are responsible for, and both the hydroxyl radical and cyclo-oxygenase products are involved in, the stimulation of RARs by wood smoke. Furthermore, changes in lung mechanics following smoke delivery are not the cause of this afferent stimulation.

Immunological and molecular analysis of three monoclonal lupus anticoagulant antibodies from a patient with systemic lupus erythematosus.

Antiphospholipid antibodies (APA), including lupus anticoagulants (LAC; as detected by in vitro blood clotting tests) and anti-cardiolipin antibodies (ACA; as assayed by solid-phase immunoassay), are strongly associated with recurrent thrombosis, thrombocytopenia, and recurrent fetal loss in some patients with systemic lupus erythematosus (SLE). The combined presence of APA and these clinical manifestations is termed antiphospholipid syndrome (APS). LAC and ACA comprise heterogeneous and somewhat overlapping autoantibody subsets. To date, it is unclear what degree of heterogeneity is present in an individual patient and between patients. To begin to address these issues, we generated three monoclonal LAC antibodies from a patient with SLE and APS. These antibodies were studied for their binding specificities and variable (V) region nucleotide sequences. All three LAC were unreactive with DNA, cardiolipin or other phospholipids. Sequence analysis of these antibodies revealed extensive overlap in their Ig V genes with anti-DNA antibodies and other autoantibodies characteristic of lupus. These data provide the first V gene sequence information on a group of SLE-derived LAC without ACA activity, representative of a similar subset of LAC found in patients with APS.

Stimulation of vagal pulmonary C fibers by inhaled wood smoke in rats.

This study investigated the stimulation of vagal pulmonary C fibers (PCs) by wood smoke. We recorded impulses from PCs in 58 anesthetized, open-chest, and artificially ventilated rats and delivered 6 ml of wood smoke into the lungs. Within 1 or 2 s after the smoke delivery, an intense and nonphasic burst of discharge [delta = +7.4 +/- 0.7 (SE) impulses/s, n = 68] was evoked in 60 of the 68 PCs studied and lasted for 4-8 s. This immediate stimulation was usually followed by a delayed and more sustained increase in C-fiber activity (delta = +2.0 +/- 0.4 impulses/s). The overall stimulation was not influenced by removal of smoke particulates (n = 15) or by pretreatment with vehicle (n = 8) for dimethylthiourea (DMTU; a hydroxyl radical scavenger) or indomethacin (Indo; a cyclooxygenase inhibitor). The immediate-phase stimulation was not affected by pretreatment with Indo (n = 8) but was largely attenuated by pretreatment with DMTU (n = 12) or by a combined treatment with DMTU and Indo (DMTU + Indo; n = 8). Conversely, the delayed-phase stimulation was partially suppressed either by DMTU or by Indo but was totally abolished by DMTU + Indo. These results suggest that 1) the stimulation of PCs is linked to the gas phase of wood smoke and 2) hydroxyl radical, but not cyclooxygenase products, is involved in the immediate-phase stimulation, whereas both metabolites are responsible for evoking the delayed-phase stimulation.

Genetic determinants responsible for acquisition of dengue type 2 virus mouse neurovirulence.

Studies conducted some 50 years ago showed that serial intracerebral passage of dengue viruses in mice selected for neurovirulent mutants that also exhibited significant attenuation for humans. We investigated the genetic basis of mouse neurovirulence of dengue virus because it might be directly or indirectly associated with attenuation for humans. Analysis of the sequence in the C-PreM-E-NS1 region of the parental dengue type 2 virus (DEN2) New Guinea C (NGC) strain and its mouse-adapted, neurovirulent mutant revealed that 10 nucleotide changes occurred during serial passage in mice. Seven of these changes resulted in amino acid substitutions, i.e., Leu55-Phe and Arg57-Lys in PreM, Glu71-Asp, Glu126-Lys, Phe402-Ile, and Thr454-Ile in E, and Arg105-Gln in NS1. The sequence of C was fully conserved between the parental and mutant DEN2. We constructed intertypic chimeric dengue viruses that contained the PreM-E genes or only the NS1 gene of neurovirulent DEN2 NGC substituting for the corresponding genes of DEN4. The DEN2 (PreM-E)/DEN4 chimera was neurovirulent for mice, whereas DEN2 (NS1)/DEN4 was not. The mutations present in the neurovirulent DEN2 PreM-E genes were then substituted singly or in combination into the sequence of the nonneurovirulent, parental DEN2. Intracerebral titration of the various mutant chimeras so produced identified two amino acid changes, namely, Glu71-Asp and Glu126-Lys, in DEN2 E as being responsible for mouse neurovirulence. The conservative amino acid change of Gu71-Asp probably had a minor effect, if any. The Glu126-Lys substitution in DEN2 E, representing a change from a negatively charged amino acid to a positively charged amino acid, most likely plays an important role in conferring mouse neurovirulence.

Multidimensional stimulus identification: instructing subjects in the order of reporting stimulus dimensions.

Two experiments were conducted to investigate the effects of order of report on identification of multidimensional stimuli under various experimental conditions. Statistical analysis showed that order of report affected speed of identification. Subjects responded faster if a natural and more appropriate way of reporting stimulus dimensions was used. Further, subjects reacted more slowly if they were free to report stimulus dimensions in any order than when they were forced to report in a particular order. Their performance was even worse when order of report was a with-in-subject factor. Response competition and response inhibition were proposed as possible explanations of the results. The implications of the results for multidimensional identification tasks are to designate an appropriate order of reporting stimulus dimensions and to instruct subjects to respond in that order.

Effects of duration of stimulus and variability of foreperiod on the identification of multidimensional stimuli.

Two experiments were conducted to investigate the effects of duration of stimulus and variability of foreperiod on the identification of multidimensional stimuli. Statistical analysis showed that performance speed and accuracy deteriorated as duration of stimulus was severely limited. Further, subjects seemed to change the allocation of attentional resources according to the attributes of stimulus. They tended to distribute more attentional resources to the less salient attribute which resulted in a statistically nonsignificant effect of order of report under time stress. Variability of foreperiod had very little effect on performance and may not be important to consider in reactions. Implications of these results for the design of multidimensional displays and for human information processing were discussed.