Familial touch and perceptual reactivity of children with severe mental illness.
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Caregivers↗
Biomedical subjects
S J Weiss
Publications and source records attributed to S J Weiss.
Perioperative hypertension: an overview.
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Anesthesia↗
The proposed use of a 'screening test' to assess oxygenator performance.
This study aimed to assess whether the use of the physiological shunt equation could (within the first five minutes of initiating CPB) serve as a 'screen' to differentiate normal and dysfunctional oxygenator performance. If dysfunction severe enough to require replacement was necessary, the normothermic patient could be weaned from CPB and replacement would be carried out under safe, controlled conditions. This technique would require postponing the induction of hypothermia (if used), aortic cross-clamping, and arresting the heart until after this screen was completed. This study demonstrates that a strong negative correlation exists between the degree of blood shunting and the membrane's 0 2 transfer performance (r = -0.874). This relation enables us to predict 0 2 transfer performance when only the shunt fraction is known. Of the 41 oxygenators used in this study, 40 demonstrated normal, or below-normal, shunt fractions. Oxygen transfer performance at or above predicted levels would be anticipated for these oxygenators. One of the 41 oxygenators had mildly elevated shunt fractions, which we predicted would be associated with mild 0 2 transfer dysfunction. Based on the performance screen worksheet we created, replacement was not necessary since the oxygenator maintained high levels of 0 2 transfer in reserve despite its marginal performance dysfunction. Assessment of oxygenator performance dysfunction in this earliest phase of CPB would greatly reduce the incidence of emergency oxygenator replacement secondary to actual or perceived oxygenator failure later in the course of the procedure.
Blood Gas Analysis↗
Selective associations produced solely with appetitive contingencies: the stimulus-reinforcer interaction revisited.
In studies reporting stimulus-reinforcer interactions in traditional conditioning paradigms, when a tone-light compound was associated with food the light gained stimulus control, but when the compound was paired with shock avoidance the tone gained control. However, the physical nature of the reinforcer-related events (food vs. shock) presented in the presence of the tone-light compound was always confounded with the conditioned hedonic value of the compound's presence relative to its absence. When the compound was paired with shock, its presence was negative relative to its absence (which was shock-free). In contrast, when the compound was paired with food, its presence was positive relative to its absence (which was food-free). The present experiment dealt with this confounding effect by conditioning a tone-light compound to be positive or negative, relative to its absence, solely with food reinforcement. One group of rats received food for responding in the presence of the tone-light compound and no food in its absence. The other group also responded in the presence of the compound, but received food only in its absence. These rats were trained on a chained schedule in which responding in the presence of the tone-light compound produced a terminal link signaled by the absence of the compound; responding ceased in the terminal link because it delayed food delivery. In a test session to assess stimulus control by the elements of the compound, tone and light were presented separately under extinction conditions. Rats that had been exposed to a positive correlation between food and the compound emitted almost double the responses in the presence of the light as in the presence of the tone. In comparison, rats that had been exposed to a negative correlation emitted only two thirds as many responses in the presence of the light as in the presence of the tone. Because this selective association was produced using only food, it appears that the contingencies under which a reinforcer is presented, rather than (or as well as) its physical properties, can generate the selective associations previously attributed to "stimulus-reinforcer interactions." This could mean that regardless of the class of reinforcer that ultimately maintains responding (appetitive or aversive), the contingency-generated hedonic value of the compound stimulus may influence the dominant modality of stimulus control.
Animals↗
Reversibility of single-incentive selective associations.
Rats were trained to press a lever in the presence of a tone-light compound stimulus and not to press in its absence. In each of two experiments, schedules were designed to make the compound a conditioned punisher for one group and a conditioned reinforcer for the other. In Experiment 1, one group's responding produced food in the presence of the compound but not in its absence. The other group's responding terminated the compound stimulus, and food was presented only in its absence. When tone and light were later presented separately, light controlled more responding than did tone in the former group, but tone gained substantial control in the latter. The same effects were also observed within subjects when the training schedules were switched over groups. In Experiment 2, two groups avoided shock in the presence of the compound stimulus. In the absence of the compound, one group was not shocked, and the other received both response-independent and response-produced shock. When tone and light were presented separately, the former group's responding was mainly controlled by tone, but the latter group's responding was almost exclusively controlled by light. These effects were also observed within subjects when the training schedules were switched over groups. Thus, these single-incentive selective association effects (appetitive in Experiment 1 and aversive in Experiment 2) were completely reversible. The schedules in which the compound should have been a conditioned reinforcer consistently produced visual control, and auditory control increased when the compound should have become a conditioned punisher. Currently accepted accounts of selective associations based on affinities between shock and auditory stimuli and between food and visual stimuli (i.e., stimulus-reinforcer interactions) do not adequately address these results. The contingencies of reinforcement most recently associated with the compound and with its absence, rather than the nature of the reinforcer, determined whether auditory or visual stimulus control developed.
Animals↗
Single-incentive selective associations produced solely as a function of compound-stimulus conditioning context.
Barpressing was maintained in a tone-plus-light (TL) condition in 2 groups of rats by shock-related contingencies and in 2 other groups by food-related contingencies. Responding ceased in TL absence (TL). Contingency arrangements made TL hedonically positive, relative to TL, for 1 shock group and for 1 food group and hedonically negative for 1 shock group and for 1 food group. In a stimulus-element test, the visual modality was dominant when TL was hedonically positive, whereas auditory control increased when TL was negative, irrespective of the reinforcers involved. Within-incentive contingency manipulations produced selective associations hitherto ascribed to stimulus-reinforcer interactions, suggesting that biological constraints on learning may operate at the level of conditioned psychological states.
Animals↗
Interaction of Drosophila DNA polymerase alpha holoenzyme with synthetic template-primers containing mismatched primer bases or propanodeoxyguanosine adducts at various positions in template and primer regions.
We studied recognition and binding of synthetic template-primers by Drosophila DNA polymerase alpha (pol alpha) holoenzyme. The template-primers used contained either mismatched base pairs at various positions in the primer region or exocyclic propanodeoxyguanosine (PdG) adducts at various positions in both template and primer.pol alpha requires primer-terminal complementarity of greater than or equal to 4 base pairs for efficient binding and incorporation. When a mismatched base pair is at the -4 position relative to the 3'-primer terminus, minimal but detectable binding occurs. This is consistent with the ability of pol alpha to incorporate a single nucleotide on a template-primer containing a mismatch at this position, but at a rate of only 7% relative to incorporation on a perfectly matched template-primer. No binding or incorporation (less than 1% of incorporation on a perfectly matched template-primer) was evident when a mismatched base pair was at the -3 position or closer, relative to the 3'-primer terminus. Similar results were obtained when PdG was placed at various positions in the primer region. When a PdG residue was located in the template region (+ 3 position relative to the 3'-primer terminus), single-nucleotide incorporation was stimulated 3-4-fold. These observations suggest that there are intrinsic aspects to the mechanism of nucleotide incorporation by pol alpha which ensure the fidelity of DNA synthesis by this enzyme and may provide novel insights into the fundamental mechanism of polymerase translocation along templates.
Animals↗
Proteolytic inactivation of alpha 1-proteinase inhibitor and alpha 1-antichymotrypsin by oxidatively activated human neutrophil metalloproteinases.
Human neutrophils use the H2O2-myeloperoxidase-chloride system to generate chlorinated oxidants capable of activating metalloproteinase zymogens that hydrolyze not only native and denatured collagens, but also the serine proteinase inhibitor (serpin) alpha 1-proteinase inhibitor (alpha 1 PI). To identify the metalloenzyme that hydrolyzes and inactivates alpha 1 PI, neutrophil releasates were chromatographed over gelatin-Sepharose and divided into fractions containing either progelatinase or procollagenase. The gelatinase-containing fraction cleaved alpha 1 PI in a manner inhibitable by native type V, but not type I, collagen. Conversely, while the collagenase-containing fraction also cleaved alpha 1 PI, this activity was inhibited by type I, but not type V, collagen. Because type I and V collagens are competitive substrates for collagenase and gelatinase, respectively, each of the metalloproteinase zymogens were purified to apparent homogeneity and examined for alpha 1 PI-hydrolytic activities. Both purified gelatinase and collagenase inactivated alpha 1PI by hydrolyzing the serpin within its active-site loop at the Phe352-Leu353 and Pro357-Met358 bonds, albeit with distinct kinetic properties. Furthermore, purified collagenase, but not gelatinase, cleaved a second serpin, alpha 1-antichymotrypsin, by hydrolyzing the Ala362-Leu363 bond within its active-site loop. These data demonstrate that human neutrophils use chlorinated oxidants to activate collagenolytic metalloproteinases whose substrate specificities can be extended to members of the serpin superfamily.
Blotting, Western↗
Psychophysiologic and behavioral effects of tactile stimulation on infants with congenital heart disease.
A within-subjects, counterbalanced, repeated measures design was employed to determine the effects of gender and six different types of verbal and tactile stimuli on the arousal of 24 infants hospitalized for congenital heart disease during their first 6 months of life. Infants were systematically assigned to different sequences of the various stimuli. Measures of arousal included heart rate, blood pressure, respiration, and activity level. Results indicated that the use of touch conducive to neural excitation (i.e., intense, vigorous, extensive touching of highly innervated body areas) produced higher heart rates (p less than .01) and systolic blood pressure (p less than .002) as well as greater activity (p less than .01) than did other types of tactile stimulation or soothing verbal stimulation. Girls appeared more physiologically responsive to touch than boys and a subset of infants showed evidence of distress during more arousing stimulation.
Arousal↗
FG 7142 selectively decreases nonpunished responding, but has no anxiogenic effects on time allocation in a conflict schedule.
Previous work (Thomas et al. 1990) showed that an anxiolytic benzodiazepine increased the time allocated to responding in a conflict situation (where responses were both food-reinforced and shock-punished) versus a nonpunishment situation. The present experiment tested whether a benzodiazepine-receptor inverse agonist (FG 7142, 1-30 mg/kg) would have the opposite effect (i.e., decrease time spent responding in a punishment situation). Chain pulls determined whether a rat's lever presses were reinforced on 1) a lean variable-interval schedule, or 2) a richer variable-interval schedule in which responding also produced shock intermittently. FG 7142 dose-dependently decreased nonpunished lever responding, but did not affect punished responding. The drug nonselectively decreased chain pulling (the schedule-switching response). Like chlordiazepoxide, FG 7142 increased the time spent in the punishment component, showing that not all effects of benzodiazepine-receptor agonists and inverse agonists are opposite. These results are inconsistent with expectations that anxiogenic actions of FG 7142 should 1) decrease punished responding; 2) increase the rate of responses that terminate the punishment condition; and 3) decrease time spent in the punishment component. Rather, nonsuppressed responding seems most sensitive to decreases by FG 7142.
Animals↗
Combined cardiac operation and carotid endarterectomy during aortic cross-clamping.
We present a surgical technique that we believe provides superior cerebral protection for simultaneous correction of carotid and cardiac pathology with low operative mortality and stroke rate. Our study population consists of 23 consecutive patients undergoing cardiac operation between August 1989 and April 1991 who also had associated critical (greater than 85%) carotid artery stenosis. Using 20 degrees C systemic hypothermia for cerebral protection, we performed simultaneous correction of both lesions during the aortic cross-clamp period, using continuous retrograde blood cardioplegia for myocardial protection. Mean patient age was 69.4 years; 83% were 65 years or older. Eighty-seven percent had angina, 35% had recent myocardial infarctions (within 30 days), and 52% had congestive heart failure. Asymptomatic bruit was found in 39%, and 61% had previous strokes, neurologic symptoms, or both. All had 85% or greater luminal narrowing on cerebral angiography, with 65% having severe or critical contralateral disease as well. Sixty-one percent had associated other vascular pathology, including peripheral vascular occlusive disease, renal artery stenosis, or abdominal aortic aneurysm. There were no postoperative strokes or neurologic events. One early vein graft occlusion resulted in postoperative myocardial infarction and subsequent death (4.3%).
Aged↗
Generalization peak shift for autoshaped and operant key pecks.
Pigeons acquired discriminated key pecking between 528- and 540-nm stimuli by either a response-reinforcer (operant group) or a stimulus-reinforcer (autoshaped group) contingency, with other training-schedule parameters comparable over groups. For the birds in the operant group, key pecks intermittently produced grain in the presence of one hue on the key (positive stimulus) but not in the other (negative stimulus). For the birds in the autoshaped group, pecking emerged when grain was intermittently presented independently of key pecking during one key color but was not presented during the other key color. Two independent contingency assays, peck-location comparisons and elimination of differences in reinforcement rate, confirmed the effectiveness of the two training procedures in establishing operant or respondent control of key pecking. After reaching a 10:1, or better, discrimination ratio between key pecks during the two key colors, the birds received a wavelength generalization test. Criterion baseline key-peck rates were comparable for operant and autoshaped groups prior to testing. On the generalization test, performed in extinction, all birds pecked most at a stimulus removed from the positive training stimulus in the direction away from the negative stimulus. In testing, autoshaped "peak" rates (24.5 to 64.9 pecks per minute) were from 33% to 80% higher than rates in the presence of the training stimuli. Respondent peak shift rarely has been reported heretofore, and never this consistently and robustly. These results further confirm the similarity of perceptual processing in classical and operant learning. They are discussed in terms of Spence's gradient-interaction theory and Weiss' (1978) two-process model of stimulus control.
Animals↗
A systematic method of accountability. Sound policies allow facilities to account for the level of charity care they provide.
Charity care policies can help hospitals accurately determine, define, and account for the level of charity care they provide. This information will help hospitals budget appropriately and measure trends that will ultimately affect the organization's viability. State governments, the federal government, and the Internal Revenue Service are more closely scrutinizing not-for-profit hospitals' tax-exempt status. As a result, the American Institute of Certified Public Accountants (AICPA) has revised its requirement to report on charity care. To meet the AICPA's requirement, healthcare providers must develop their own definition of charity and determine criteria for providing care free or at a reduced rate. Setting policies to support the organization's definition of charity is necessary for the development of internal systems that promote the early identification of individuals seeking healthcare who will be unable to pay for services. Several policy implications may result from the facility's charity care determination process. For example, patients exhibiting extreme hardship might still be eligible to receive charity care even though their income and assets exceed the hospital's income guidelines. An organization planning to develop a charity care policy must first thoroughly assess its current charity care practices and cost accounting capabilities. Obtaining input from all the departments involved in the development of the charity care policy is necessary to make the transition as smooth as possible.
Budgets↗
Regulation of transendothelial neutrophil migration by endogenous interleukin-8.
Movement of neutrophils from the bloodstream to inflamed tissue depends on the activation of both the neutrophil and the endothelial cell. Endothelial cells lining the postcapillary venule respond to proinflammatory mediators by expressing adhesion molecules and synthesizing a variety of neutrophil-activating factors. Endothelial cell production of a 77-amino acid variant of interleukin-8 (IL-8) was found to be a requirement for the invasion of neutrophils through a vessel wall model. IL-8 secreted by cytokine- or lipopolysaccharide-stimulated endothelial cells induced the rapid shedding of neutrophil lectin adhesion molecule-1, the up-regulation of leukocyte beta 2 integrins, and the attachment and transmigration of the neutrophils. Thus, endogenous endothelial IL-8 regulates transvenular traffic during acute inflammatory responses.
Antigens, CD↗
Stressors experienced by family caregivers of children with pervasive developmental disorders.
The purpose of this study was to identify the perceived stressors experienced by parents who care for children with Pervasive Developmental Disorders. The relationship between demographics and overall stress was also examined. The most frequently cited stressor was difficulty arranging for and collaborating with professional and support services. Problems associated with the child's emotional and mental state were viewed as the most stressful of all. No demographic variables showed a significant relationship to degree of overall stress.
Adult↗
Localized fibrosis associated with immunotherapy?
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Arm↗
Personality adjustment and social support of parents who care for children with pervasive developmental disorders.
The goal of this study was to examine the degree of personality adjustment and perceived social support of parents who care for children with pervasive developmental disorders. Data were collected with the California Q-Set (a personality measure) and the Norbeck Social Support Questionnaire. Personality adjustment of the parents was found to be significantly less than optimal, with a high degree of anxiety, minimal ego resilience, and use of defensive coping processes. Siblings of the child with the disorder and mothers of the parents were those most frequently identified as providing support to the caregiver, although friends, special education teachers, and daycare staff were the individuals whose support was most significantly related to greater amounts of perceived affection and affirmation, tangible aid, and concrete caregiving assistance. In fact, the more the caregivers depended upon their families for support, the less well adjusted were the caregivers on the personality measure. The implications of the findings for caregivers and their families are discussed.
Adaptation, Psychological↗
Protamine-induced right-to-left intracardiac shunting.
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Cardiopulmonary Bypass↗