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Over the past decade, clinical trials have shown that spinal cord stimulation can restore motor functions that were thought to be permanently impaired in persons with spinal cord injury. However, the off-target effects of delivering electrical impulses to intertwined spinal networks remain largely unknown. This generates safety concerns for this otherwise fast-progressing technology. Herein, we present the prevalence of autonomic dysreflexia (AD) that occurred during implanted spinal cord stimulation testing for motor activation of the lower extremities. Eleven participants with spinal cord injury underwent implantation of temporary percutaneous epidural and dorsal root ganglia stimulation leads. Participants completed two days of parameter testing at baseline, then six days of motor rehabilitation sessions, and two days of parameter testing at end of study. The goal of parameter testing was to determine electrode configuration(s), pulse amplitudes, and frequencies that activated lumbosacral spinal sensorimotor networks that generate lower extremity functions. During all parameter testing sessions, continuous blood pressure and heart rate monitoring recordings were collected. Evidence of autonomic dysreflexia was found in 22% of all parameter tests with participants at rest. Most of these episodes (97%) were asymptomatic. These episodes occurred more frequently when using epidural stimulation, at or near amplitudes that elicited whole leg muscle activation and using a wide-field electrode configuration. Although monitoring occurred during passive testing, motor rehabilitation sessions use stimulation for longer periods, at higher frequencies and amplitudes. These sessions may carry additional risks of autonomic dysreflexia. Investigation of these concerns should continue as spinal cord stimulation progresses toward clinical translation. NEW & NOTEWORTHY Spinal cord stimulation for motor recovery after spinal cord injury is a popular research intervention, though off-target effects are a concern. Using continual blood pressure and heart rate recordings during passive spinal cord stimulation parameter testing, we identified frequent episodes of autonomic dysreflexia that were rarely associated with symptoms. This presents a previously unrecognized risk of spinal cord stimulation and appropriate vigilance in targeted monitoring is urged to maintain participant safety.

Objective: The primary objective of this study was to quantify changes in performance of task-specific motor activities over 12 motor rehabilitation sessions with lumbosacral spinal cord stimulation (SCS) via either transcutaneous stimulation or epidural stimulation. Both stimulation modalities have been used in recent years to restore functions lost to spinal cord injury (SCI). Secondary outcomes examine participants' perspectives captured via the User Experience Questionnaire (UEQ) upon study completion to further understand their perception of SCS., Methods: Six individuals with SCI completed 12 sessions with one modality of SCS during supine and/or side-lying, seated forward reaching, and standing activities. Changes in volitional lower extremity movement, the number of points of contact needed at hips and/or knees to facilitate standing, and changes in seated forward reaching distance were used to quantify performance. The UEQ was administered to gauge participants' perspectives following use of SCS to enable functions impaired due to SCI., Results: For all participants, performance of motor activities improved with SCS compared to without stimulation. Responses for the UEQ showed an overall positive perception of trialing SCS with rehabilitation to enhance motor functions impaired by SCI., Conclusions: Regardless of injury severity, location of injury, time since SCI, or SCS modality, all participants experienced gains in motor function in the presence of SCS combined with a condensed rehabilitation program. However, no evidence of sustained motor functions was found in the absence of SCS. UEQ results highlight the positive perception of SCS with rehabilitation as well as the importance of consulting persons with lived experience of SCS during clinical trial design and protocol development. Trial registration: ClinicalTrials.gov identifier: NCT05095454.

The International Classification of Diseases, 11th edition (ICD-11) adopted a fully dimensional model of personality disorder. The Personality Inventory for ICD-11 (PiCD) and Informant-Personality Inventory for ICD-11 (IPiC) were developed to assess the ICD-11 trait model, and the PiCD has since received significant validation support. However, there has only been one prior study of longitudinal predictive validity of the PiCD, two relatively short test-retest reliability studies of the PiCD, and no prior longitudinal tests of the IPiC. Longitudinal psychometric support for psychological assessment measures is essential. The present study provides a longer, larger, 2-year psychometric validation test of the PiCD and IPiC. Participants ( N = 711) and their informants ( N = 569) were recruited in the St. Louis Personality and Aging Network. The results demonstrated strong 2-year retest reliability for the PiCD and IPiC, as well as mean-level stability. Additionally, we explored the relationships between the PiCD and IPiC and important life outcome measures (depressive symptoms, satisfaction with life, and health status). The analysis revealed several significant associations between PiCD and IPiC scales and the outcome variables across time. Further, the PiCD Negative Affectivity and IPiC Detachment scales demonstrated incremental validity over each other and the outcome variables at Wave 1 in the prediction of depressive symptoms and satisfaction with life, respectively. The findings provide essential longitudinal test-retest reliability and predictive validity support for the PiCD and IPiC. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Lay Abstract: This study looked at how Australian autistic and non-autistic adults experience barriers to healthcare. We asked autistic and non-autistic adults to complete the Barriers to Healthcare Checklist Short-Form (BHC). We analysed data from 263 autistic adults and 70 non-autistic adults. We found that autistic adults experienced more barriers to healthcare than non-autistic adults. Gender diversity, feeling more anxious, having greater disability and feeling unsatisfied with social support contributed to barriers to healthcare in autistic participants. We recommend interventions such as developing and implementing a national action plan, similar to the National Roadmap for Improving the Health of People with Intellectual Disability (2021) to reduce barriers and address unmet healthcare needs of Australian autistic adults. We also recommend working with autistic adults to develop new policies and strategies, implementing environmental adaptations to health care facilities, and increasing Autism education opportunities for health professionals to address gaps in knowledge., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article.

Sensory processing difficulties can negatively impact wellbeing in adults with disabilities. A range of interventions to address sensory difficulties have been explored and virtual reality (VR) technology may offer a promising avenue for the provision of sensory interventions. In this study, preliminary evidence about the impact of Evenness, an immersive VR sensory room experience, for people with disabilities was investigated via a single intervention pre-post mixed methods design. Quantitative methodology included single intervention pre-post design (five month timeframe) with 31 adults with various developmental disabilities to determine the impact of use of aVR sensory room using a head mounted display (HMD) in relation to anxiety, depression, sensory processing, personal wellbeing and adaptive behaviour. Qualitative semi-structured interviews were also conducted with thirteen purposefully selected stakeholders following Evenness use. Results indicated significant improvements in anxiety, depression and sensory processing following Evenness use. Qualitative analysis corroborated the anxiety findings. No significant changes were observed in personal wellbeing or adaptive behaviour. Results are promising and indicate that a VR sensory room may have a positive impact on anxiety, depression and sensory processing for adults with disabilities. A longer study timeframe and a more rigorous experimental methodology is needed to confirm these findings., (© 2023. The Author(s).)

Primate sleeping site selection is influenced by multiple ecological factors including predation avoidance, thermoregulation and food access. To test these hypotheses, we studied the sleeping trees used by a group of wild silky sifakas (Propithecus candidus) in Marojejy National Park, Madagascar. During this 10-month study, the group slept in 828 sleeping trees from approximately 35 genera. In support of thermoregulation, generalized linear models revealed that as temperature decreased, the number of individuals sleeping together significantly increased and they slept at further distances from the trunk. As rainfall increased, sleep site height significantly increased. Weinmannia was the most frequented tree genus, despite low abundance, accounting for 29% of all sleeping trees. In support of food access, 94.8% of sleeping trees were food trees. Weinmannia is among the most highly preferred food trees. The group slept at a mean height of 16.0 m near the top of tall trees which averaged 19.5 m. Sleep trees were significantly taller than trees in botanical plots within the sifaka's home range. They never slept in the same trees on consecutive nights, and sleeping heights were significantly higher than daytime heights which is consistent with predation avoidance. Social sleeping in groups of 2 or 3 individuals (62.9%) was more common than solitary sleeping (37.1%). At such heights, huddling may increase vigilance and lessen the risk of predation by fossa (Cryptoprocta ferox) while also reducing heat loss. These patterns suggest that silky sifaka sleep site choice is influenced by thermoregulation and food access in addition to predation avoidance. We suggest that understanding sleep site use can assist in conservation of species like silky sifakas by enabling researchers to find new groups, protect habitats with key tree species and inform reforestation efforts., (© 2021 S. Karger AG, Basel.)

Prostate cancer is a common cancer among males in the USA and is often treated by intermittent androgen deprivation therapy. This therapy requires a patient to alternate between periods of androgen suppression treatment and no treatment. Prostate-specific antigen levels are used to track relative changes in tumor volume of prostate cancer patients undergoing intermittent androgen deprivation therapy. During this therapy, there is a pause between treatment cycles. Traditionally, continuous ordinary differential equations are used to estimate prostate-specific antigen levels. In this paper, we use dynamic equations to estimate prostate-specific antigen levels and construct a novel time scale model to account for both continuous and discrete time simultaneously. This allows us to account for breaks between treatment cycles. Using empirical data sets of prostate-specific antigen levels, a known bio-marker of prostate cancer, across multiple patients, we fit our model and use least squares to estimate two parameter values. We then compare our model to the data and find a resemblance on treatment intervals similar to our time scale.

Occupational therapy is the leading profession with regard to supporting children who experience difficulties with occupations as a result of sensory processing differences. However, there are mixed reports with regard to the efficacy of various sensory interventions and approaches, leaving little clear guidance for occupational therapists supporting children with these difficulties. The Sensory Form is a planning tool developed in 2017 to guide occupational therapists in their professional reasoning for assessment and intervention of sensory processing differences. To date, no research has been conducted on its use. Researchers introduced the tool to 20 occupational therapists with relevant experience and conducted an online survey of their perceptions about The Sensory Form. Findings were analysed using descriptive statistics and qualitative content analysis. Therapists reported that they found the tool acceptable for use, described key strengths and weaknesses of The Sensory Form, and outlined changes to improve the tool. The Sensory Form may have an application in guiding the practice of therapists supporting children with sensory processing differences. Further development of associated resources may be warranted., Competing Interests: The first author was formerly employed by the organisation which developed The Sensory Form at the time of development. No authors were employed by the organisation which developed The Sensory Form at the time the research took place. There is no financial gain for authors associated with any positive findings in this study., (Copyright © 2020 Caroline J. Mills et al.)

Fatigue has been proposed to increase the risk of knee injury. This study tracked countermovement jump, knee isometric strength, and kinetics and kinematics in 8 female soccer players (experimental group) during an anticipated sidestep maneuver before and after two matches played over a 43-h period. Time points were: Before and after match 1 (T0 and T1), 12 h after the first match (T2), and immediately after the second match (T3). A control group participated only in practice sessions. Isometric knee extension strength decreased by 14.8% at T2 ( p = 0.003), but knee flexion was not affected until T3, declining by 12.6% ( p = 0.018). During the sidestep maneuver, knee joint degrees of flexion at initial contact was increased by 17.1% at T3, but maximum knee and hip angle at initial contact were unchanged. Peak resultant ground reaction force (GRF) increased by 12.6% ( p = 0.047) at T3 (3.03 xBW) from 2.69 xBW at T0, while posterior GRF was significantly higher than T0 at all three subsequent time points (T1 = 0.82 ± 0.23 xBW, T2 = 0.87 ± 0.22 xBW, T3 = 0.89 ± 0.22 xBW). Anterior tibial shear force increased significantly ( p = 0.020) at T3 (1.24 ± 0.12 xBW) compared to T1 (1.15 ± 0.13 xBW), an 8.8% increase. Lateral tibial shear force was significantly higher at both T1 (0.95 ± 0.20 xBW) and T3 (1.15 ± 0.38 xBW) compared to T0 (0.67 ± 0.25 xBW). These findings suggest that participation in a soccer match has significant effects on both physical performance parameters and kinetics/kinematics during a sidestep cut, but these can be more pronounced after a second match with short rest.

To study the genetic architecture of anther exsertion, a trait under stabilizing selection in wild radish, artificial selection on anther exsertion was applied for 11 generations. Two replicate lines each of increased and decreased exsertion plus two randomly-mated controls were included. Full pedigree information is available from generation five. To estimate correlated responses to selection, 571 plants from all lines and matrilines were grown in the greenhouse and a number of floral, growth, and phenology traits were measured. To create an outbred F2 mapping population, all possible crosses among the two high and two low exsertion lines were made, using a multiple-family design to capture the genetic variance still present after 11 generations of selection. Six floral traits were measured on 40 parents, 240 F1, and 4,868 F2 offspring. Opportunities for reuse of these data include traits not previously analyzed, other analyses, especially using the pedigree and fitness data, and seeds from all generations and photos of flowers in the later generations are available.

Background: Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-associated death in the United States. Its diagnosis is based on clinical and radiographic changes that are indistinguishable from acute lung injury/acute respiratory distress syndrome (ALI/ARDS). TRALI is presumed to be a form of ALI/ARDS; however, it differs in its triggering events and associated mortality. Two cases of rapidly fatal TRALI in which the postmortem pathology differed from that classically associated with ALI/ARDS are reported., Case Report: Two men (aged 75 and 83 years) developed rapidly fatal TRALI after receiving single units of plasma for correction of elevated international normalized ratios. The donors were found to have white blood cell (WBC) antibodies that included specificities for WBC antigens expressed by the recipient (HLA Class I or Class II and/or HNA-3b [5a] antibody). Autopsy findings in both patients revealed bilateral pleural effusions and extensive patchy areas of alveoli filled with proteinaceous fluid. The pulmonary capillaries were congested with red blood cells and WBCs. Diffuse alveolar damage, including interstitial inflammation, intraalveolar granulocyte infiltration, and hyaline membrane formation, were not identified in either case., Conclusion: In both patients the clinical and radiographic findings were indicative of TRALI and indistinguishable from ALI/ARDS. However, diffuse alveolar damage, the classic autopsy finding in ARDS, was not identified, suggesting a different pathogenesis. Further studies are needed on the role of polymorphonuclear cells in the initiating events of TRALI that lead to ALI and the resulting breakdown of the permeability integrity of the alveolar walls.

The ligand-gated ion channel family includes receptors for serotonin (5-hydroxytryptamine, 5-HT), acetylcholine, GABA, and glutamate. Drugs targeting subtypes of these receptors have proven useful for the treatment of various neuropsychiatric and neurological disorders. To identify new ligand-gated ion channels as potential therapeutic targets, drafts of human genome sequence were interrogated. Portions of four novel genes homologous to 5-HT(3A) and 5-HT(3B) receptors were identified within human sequence databases. We named the genes 5-HT(3C1)-5-HT(3C4). Radiation hybrid (RH) mapping localized these genes to chromosome 3q27-28. All four genes shared similar intron-exon organizations and predicted protein secondary structure with 5-HT(3A) and 5-HT(3B). Orthologous genes were detected by Southern blotting in several species including dog, cow, and chicken, but not in rodents, suggesting that these novel genes are not present in rodents or are very poorly conserved. Two of the novel genes are predicted to be pseudogenes, but two other genes are transcribed and spliced to form appropriate open reading frames. The 5-HT(3C1) transcript is expressed almost exclusively in small intestine and colon, suggesting a possible role in the serotonin-responsiveness of the gut.

Three studies were conducted to assess mean level changes in personality traits during adolescence. Versions of the Revised NEO Personality Inventory (P. T. Costa, Jr., & R. R. McCrae, 1992a) were used to assess the 5 major personality factors. A 4-year longitudinal study of intellectually gifted students (N = 230) was supplemented by cross-sectional studies of nonselected American (N = 1,959) and Flemish (N = 789) adolescents. Personality factors were reasonably invariant across ages, although rank-order stability of individual differences was low. Neuroticism appeared to increase in girls, and Openness to Experience increased in both boys and girls; mean levels of Extraversion, Agreeableness, and Conscientiousness were stable. Results extend knowledge of the developmental curve of personality traits backward from adulthood and help bridge the gap with child temperament studies.

Studies of water chlorination by-products have suggested a possible increased risk of bladder and colon cancers, as well as adverse reproductive and developmental effects such as increased spontaneous abortion rates and fetal anomalies. A workshop for an expert working group was convened to advise Health Canada on the need for further action. Participants were given background papers and a set of key questions to review prior to the meeting. At the workshop, experts presented an overview of what was known to date on water chlorination by-products from toxicologic studies, epidemiologic studies of cancer and adverse reproductive/developmental effects, and risk assessment. This paper summarizes the information provided in the background papers and presentations, describes the consensus arrived at regarding assessment of evidence for level of risk and presents a number of suggestions for future research.

Many people have difficulty comprehending that a child can be gifted and also have learning disabilities. As a result, children with special needs that result from both their high abilities and their learning problems are rarely identified and are often poorly served. This article explores the current policies and practices with regard to defining, identifying, and educating this population. Recommendations are included that would help ensure that students who are gifted and have learning disabilities receive the intervention needed to help them achieve their full potential.

The objective of this paper is to assess the impact of the 1994 Workshop on Public Education Messages for Reducing Health Risks from Ultraviolet Radiation (UVR). The target audience was any organization in Canada doing education on the health risks of UVR. A mailed survey with telephone follow-up was distributed to 130 addresses, including workshop participants, recipients of the workshop report and 40 local public health units. The response rate was 62%. Public health messages from the workshop served as an added impetus or helped to initiate activities around UVR in approximately 40% of organizations over the two years since the workshop. The public health messages were used directly in programming by approximately 38% of all organizations responding. However, looking at those who had previously seen the messages, 61% used them directly in programming. Forty percent of those sampled had never seen a copy of the messages. The results suggest the need for improved dissemination of consensus statements.

Objective: Restenosis is a common problem which limits the effectiveness of percutaneous transluminal coronary angioplasty (PTCA). The cellular mechanisms of restenosis appear to involve smooth muscle cell (SMC) migration to the neointima in response to mitogens and growth factors, resulting in proliferation and deposition of cells in the lumen of the vessel. An antibody directed against PDGF attenuates this response in the rat. Thus, signaling cascades induced by growth factors including PDGF may be important targets for therapeutic intervention., Methods: Since a number of growth factors activate c-fos via the p21-ras signaling pathway, we examined c-fos expression in a time course experiment involving restenotic lesions in rat carotid arteries. Sections of arteries collected at 1, 3, 7, 14 and 28 days following balloon injury were hybridized using a fluorescein-labeled RNA probe to c-fos. Immunohistochemistry was performed with antibodies to proliferating cell nuclear antigen (PCNA) and alpha-smc actin to characterize cellular constituents of the neointima, and detect any correlation between fos expression and PCNA localization., Results: Expression of c-fos was low at day 1. By day 3, the media and adventitia were positively stained. At days 7 and 14, most cells in the neointima were labeled. By day 28, c-fos was expressed mainly in scattered cells along the luminal surface. Control sections revealed little labeling and confirmed specific staining by the antisense strand, PCNA localization and c-fos expression were similar at days 1, 3, 7 and 28, but at day 14 c-fos was expressed throughout the lesion, with PCNA localized mainly along the luminal edge. The majority of the cells making up the neointima stained rather intensely for alpha-smc actin, identifying them as SMCs., Conclusions: Results of these experiments indicate that, while c-fos expression correlates with lesion formation, it may be associated with a cellular process distinct from proliferation in this model.

The purpose of this study was to identify the distribution of androgen receptors in the bald and hairy scalp of adult male and female stumptail macaque monkeys by light microscopic biotin-avidin immunocytochemistry with a highly purified rat monoclonal antibody against the cloned human androgen receptor. Consistent, intense nuclear and minimal cytoplasmic immunostaining was observed in several distinct cell populations of the pilosebaceous unit including the dermal papilla, hair epithelium, outer root sheath, dermal sheath, and sebaceous gland. A similar distribution of androgen receptors was found in miniaturized and terminal anagen and telogen follicles of the bald and hairy scalp, respectively. Binding of androgen receptor antibody was also detected in dermal fibroblasts, basal and intermediate layers of the interfollicular epidermis, and duct and glandular cells of eccrine sweat glands. This investigation demonstrates the presence of androgen receptors in the pilosebaceous unit of the scalp of the stumptail macaque and also shows that their distribution is comparable to that previously reported for humans.

The purpose of these experiments was to determine if an extracellular calcium binding site gradient is evident in freshly dissected or cultured mouse vibrissa and human scalp follicles and to measure possible drug effects on this gradient. Mouse vibrissae were cultured with or without either minoxidil or pinacidil, and human scalp follicles were cultured with or without epidermal growth factor. Anagen vibrissa and scalp follicles were dissected and placed in culture for 4 h to 4 days, then fixed in a solution containing lanthanum chloride and prepared for either quantitative energy-dispersive X-ray microanalysis (X-ray) or qualitative transmission electron microscopy (TEM). Since lanthanum has a high charge density it displaces Ca2+ ions from anionic binding sites. TEM analysis revealed extensive accumulation of electron-dense lanthanum deposits in the intercellular compartment of differentiating cells in the hair shaft and inner root sheath in the apex of the follicular bulb. Sparse lanthanum precipitate was observed in the intercellular space of the proliferative cells at the base of the bulb. This gradient of lanthanum precipitate was evident in both freshly dissected and cultured vibrissa and scalp hair follicles, irrespective of treatment with drugs that grow hair or epidermal growth factor. X-ray microanalysis indicated that percent by weight of lanthanum was markedly higher in the apex compared to the base of the follicular bulb in vibrissa and scalp follicles. These qualitative and quantitative data demonstrate that an extracellular calcium binding site gradient exists in cultured vibrissa and scalp hair follicles, and that this gradient is not significantly affected by hair growth altering drugs including minoxidil or pinacidil, and epidermal growth factor.

Objective: To evaluate a computer-based, real-time, multibreath nitrogen washout technique in mechanically ventilated patients, incorporating an in-line flow measurement device to measure functional residual capacity and two indices of gas mixing, ventilatory efficiency, and alveolar mixing efficiency., Setting: ICU, Charing Cross Hospital, London., Design: Within-patient reproducibility of a multibreath nitrogen washout technique., Patients: Seven intubated patients requiring mechanical ventilation. One patient completed two sets of readings., Interventions: Patients were connected to a pneumatically driven ventilator fitted with a switching device to be operated either by an appropriate oxygen-nitrogen mixture or equivalently blended oxygen-argon mixture. An inspiratory-expiratory, two-way valve was attached to the delivery port of the ventilator, with a pneumotachograph for flow measurement and a gas sampling probe for gas concentration measurement in line with the patient's endotracheal tube. The analog signals were digitized and handled by a microcomputer., Measurements and Main Results: No significant differences were found for any index, with coefficients of variation of 1.5%, 2.9%, and 2.1% for functional residual capacity, ventilatory efficiency, and alveolar mixing efficiency, respectively., Conclusions: This method gives excellent reproducibility for biological measurements in a clinical setting and shows that these measurements can readily be made on mechanically ventilated patients.

Changes in gas viscosity during the nitrogen washout test will affect pneumotachograph measurements. A digital correction technique, using estimates of viscosity derived from measurements of gas concentration, has been described and was examined in this study. The pneumotachograph gain varied directly with argon concentration (coefficient of correlation = 0.995, P less than 0.01) indicating that a simple correction was legitimate. This was tested with an in vitro model, giving very consistent estimates of volume (FRC) despite variations in the ventilation pattern, which were slightly underestimated due to incomplete mixing in the system. Alveolar mixing efficiency (AME) was also reproducible but, like studies in man, fell when low tidal volumes were used. In a repeatability study in six volunteers, examined six times on each of two days, FRC and AME were also reproducible (average coefficient of variation within subjects of 4.97% and 4.34% respectively), considerably better than another reported study using conventional flow measurements. This method appears to be a useful addition to existing techniques for studying nitrogen washout.

1. Beat-by-beat indices of contractility for assessment of inotropic effects in a given subject were studied using pacing with beta-adrenergic blockade, in eight patients undergoing routine left heart catheterization. A catheter-tip manometer was sited in the left ventricle and an electromagnetic velocity transducer was mounted further back on the same catheter so that it was sited in the ascending aorta. 2. The maximum rate of rise of left ventricular pressure (dPLV/dtmax), and of aortic velocity (maximum acceleration, MA) and stroke volume (SV) were all obtained with this catheter. Filling effects were assessed by head-up to head-down tilt, inotropic effects by paced post-extrasystolic potentiation. 3. Tilt produced a mean increase in left ventricular end-diastolic pressure (PLVED) of 8.1 mmHg (P less than 0.05), dPLV/dtmax decreased 4.3% (n.s.), peak velocity (PV) increased 23% (P less than 0.05), MA increased 5.4% (n.s.), and SV increased 17.5% (P less than 0.05). Post-extrasystolic potentiation produced a mean decrease in PLVED of 2.8 mmHg (n.s.), dPLV/dtmax increased 35% (P less than 0.05), PV increased 14% (P less than 0.05), MA increased 55% (P less than 0.05), and SV increased 8.7% (n.s.). 4. There was no difference in response between patients with normal and patients with impaired left ventricular ejection fraction. 5. It is concluded that increased left ventricular filling increases stroke volume greatly (Starling effect) but does not affect dPLV/dtmax, which (together with MA) nevertheless responds markedly to increased contractility. dPLV/dtmax appears to be a volume-insensitive index of contractility in the intact human, whether ejection fraction is normal or impaired.

The relationship between personality variables associated with sex roles and the cognitive variables of math and verbal ability was examined in three groups of adolescents. Masculinity and femininity of interests, behavioral traits, and values were examined using three inventories: the Femininity Scale from the California Psychological Inventory, the Bem Sex Role Inventory, and the Study of Values. Results indicate that there is some evidence for a positive relationship between masculine traits and values and math ability, and feminine traits and values and verbal skills (for both sexes). Certain traits indicative of maturity were found to be positively related to both high math and high verbal scores, while certain highly sex-typed traits and interests were found to be negatively related to both cognitive variables. A different relationship for males and females was found between high intellectual scores and indicators of self-concept and emotional well-being. The differing relationship between each of the three personality variables indicative of sex roles (e.g., interests, values, traits) and cognitive variables emphasizes the need to view masculinity and feminity, as well as "sex-role," as a complex combination of the many different aspects of sex roles as they exist in our society.

The electromagnetic flowmeter, which has developed since its inception into a reliable clinical instrument that has become the standard to which all other flowmeters are compared, is described. Perivascular and intravascular transducers now available, which can easily be used to give reliable, high fidelity recordings of blood flow and velocity, are also discussed.

The hemodynamic effects of sulfinpyrazone were investigated in 12 anesthetized dogs. Bolus injections into a coronary artery (1--500 mg) and a femoral artery (10--300 mg) and intravenous infusions (10 and 20 mg/min up to 500 mg) were given. After intracoronary injection, coronary dilatation occurred for over 20 min without major changes in cardiac muscle function. Femoral vasodilatation was also induced by local injection. Slow intravenous infusion resulted in inconsistent changes of coronary blood flow. However, in one instance, coronary dilatation was observed at a plasma level of 27.8 microgram/ml, which is comparable with that reached in man after standard oral dosage. Thus, sulfinpyrazone has coronary vasodilator effects which may have relevance to patient therapy.

This paper describes a method for determining whether beta-blocking agents reduce myocardial oxygen consumption by a direct action on the myocardium in addition to that reduction produced by changes in cardiac mechanical function. Measurements of myocardial oxygen consumption were made in anaesthetized dogs . Changes in heart rate were produced by atropine and by ventricular pacing. Alterations in ventricular loading were achieved by balloon inflations in the descending aorta and by infusions of nitroprusside and dextran. Measurements under these conditions were repeated after beta-blockade. Analysis required the separation of the part of reduced myocardial oxygen consumption resulting from the mechanical effects of beta-blockade from any possible additional direct effect on the myocardium. There was no evidence for a significant direct effect. The average overall reduction in myocardial oxygen consumption after beta-blockade was 18% but the estimated reduction not accountable to mechanical effects was only 2% (range, 95% probability, -7% to 3%).

The volume, velocity, and acceleration of ascending aortic blood were measured in man using a pulsed Doppler ultrasound instrument, with online spectral analysis and offline computer processing of velocity data. This system was firstly validated in a test rig capable of generating pulsatile flow of talc particles in water at physiological velocities and accelerations in a model aorta. Doppler measurements correlated well (r greater than or equal to 0.90) with simultaneous electromagnetic measurements of stroke volume, peak ejection velocity, and maximum acceleration in this rig. In vivo validation was performed firstly by comparing simultaneous Doppler and thermodilution cardiac output (Q) measurements; this yielded the following regression equation: Doppler Q = 0.90 X thermodilution Q + 0.03 litre.min-1, r = 0.92; n = 38. Beat by beat measurements were then validated against simultaneous invasive aortic blood velocity measurements made using a Mills electromagnetic cathetertip probe. When paced single beats of different size were compared within subjects the correlation coefficients between Doppler and electromagnetic measurements averaged 0.89 for stroke volume, 0.91 for peak ejection velocity, and 0.79 for maximum acceleration in five subjects. The absolute values for velocity and acceleration from the Doppler system differed significantly from the absolute values given by the electromagnetic system and this difference was not consistent between subjects. It is concluded that the Doppler system can non-invasively record relative changes in left ventricular ejection in man.

The protein-sparing effects of the peripheral infusion of crystalline amino acids (PAA) was studied metabolically in selected surgical patients subjected to various degrees of stress. Twenty-one patients (sixteen cancer patients receiving chemotherapy and/or radiotherapy, three with major abdominal traumatic injuries and four with paralytic ileus) were infused with 2 1/24 hours of a solution of 4.2% Travasol amino acids with only 5% glucose as a source of nonprotein calories. One-half of the cancer patients were also allowed ad libitum oral intake of a regular hospital diet or Vivonex-HN. The nutritional status was evaluated by measuring changes in body weight, serum albumin levels and nitrogen balance. Body weight decreased in only the trauma patients. When these solutions were the sole source of nutrients all patients were in negative nitrogen balance and had significant decreases in their serum albumin levels. Serum albumin levels were preserved only when extra sources of calories were provided. The infusion of the crystalline amino acids without adequate levels of nonprotein energy did not conserve protein in these stressed patients.

Measurements have been made of pressure and blood velocity in venae cavae and aorta in a patient with severe cardiac tamponade in whom there was pulsus paradoxus. The characteristic pressure changes of pulsus paradoxus were associated with variations in peak blood velocity in the ascending aorta and stroke output. Maximum filling of the right side of the heart occurred during inspiration, and was associated in time with minimum left ventricular stroke volume. These findings point to competition for space by the ventricles in the distended pericardial sac as being the major factor in the production of pulsus paradoxus.