Cybersecurity Risk Management Framework for Blockchain Identity Management Systems in Health IoT

Blockchain (BC) has recently paved the way for developing Decentralized Identity Management (IdM) systems for different information systems. Researchers widely use it to develop decentralized IdM systems for the Health Internet of Things (HIoT). HIoT is considered a vulnerable system that produces and processes sensitive data. BC-based IdM systems have the potential to be more secure and privacy-aware than centralized IdM systems. However, many studies have shown potential security risks to using BC. A Systematic Literature Review (SLR) conducted by the authors on BC-based IdM systems in HIoT systems showed a lack of comprehensive security and risk management frameworks for BC-based IdM systems in HIoT. Conducting a further SLR focusing on risk management and supplemented by Grey Literature (GL), in this paper, a security taxonomy, security framework, and cybersecurity risk management framework for the HIoT BC-IdM systems are identified and proposed. The cybersecurity risk management framework will significantly assist developers, researchers, and organizations in developing a secure BC-based IdM to ensure HIoT users' data privacy and security.

Internal Delensing of Cosmic Microwave Background Polarization B-Modes with the POLARBEAR Experiment

Using only cosmic microwave background polarization data from the polarbear experiment, we measure B-mode polarization delensing on subdegree scales at more than 5σ significance. We achieve a 14% B-mode power variance reduction, the highest to date for internal delensing, and improve this result to 22% by applying for the first time an iterative maximum a posteriori delensing method. Our analysis demonstrates the capability of internal delensing as a means of improving constraints on inflationary models, paving the way for the optimal analysis of next-generation primordial B-mode experiments.

Abstract P1-10-15: Development of humanized anti-CD47 monoclonal antibodies with differentiated functional profiles

CD47 is a cell surface transmembrane protein that binds to signal regulatory protein alpha (SIRPα) on macrophages and results in a “don't eat me” signal that inhibits phagocytosis. Breast cancer cells, both primary and metastatic, frequently overexpress CD47 and exploit this pathway to evade macrophage-mediated destruction. Anti-CD47 monoclonal antibodies (mAbs) block the CD47/SIRPα interaction and promote tumor cell destruction via phagocytosis. Anti-CD47 mAbs also contribute to an anti-tumor T-cell response in immune-competent mice. Therefore, anti-CD47 antibodies represent a new class of immune checkpoint inhibitors that modulate both the innate and adaptive immune systems.

CD47 is expressed on multiple cell types, including tumor cells and normal cells. Many anti-CD47 mAbs block the CD47/SIRPα interaction and cause phagocytosis of tumor cells, but do not directly induce the death of human tumor cells. Tioma has created new humanized anti-CD47 mAbs with novel and differentiated functional profiles to enhance functional heterogeneity. Ti-104, Ti-176 and Ti-108 block the binding of SIRPα to CD47 and increase phagocytosis of human tumor cells. They also induce cell death of human hematological and solid tumor cell lines (including breast cancer lines) in a cell autonomous manner. Cell death was determined by an increase in phosphatidylserine-positive/7AAD-positive tumor cells assessed by flow cytometry following incubation in media containing anti-CD47 mAb or a negative control immunoglobulin. In vitro, these mAbs bind to human tumor cell lines with apparent binding affinities ranging from low pM to low nM, depending on the cell line and method of analysis (solid-phase or cell-based ELISA, flow cytometry or surface plasmon resonance). In vitro, Ti-104 and Ti-108 bind to human RBCs, whereas Ti-176 has markedly reduced binding to human and cynomolgus monkey RBCs.

In a four-week (once-weekly dosing) exploratory safety study in cynomolgus monkeys with Ti-176 and Ti-108, no dose-limiting toxicity or gross pathological or microscopic findings were identified after an initial dose of 5 mg/kg (Week 1) followed by doses of 50 mg/kg (Weeks 2, 3, and 4). Ti-176 treatment resulted in minimal decrease in red cell mass, hemoglobin and hematocrit, which corresponded in vitro to markedly reduced binding to cynomolgus monkey RBCs. Ti-108 caused transient reduction of RBC parameters comparable to some previously reported anti-CD47 mAbs.

Ti-104, Ti-176 and Ti-108 showed potent, dose-dependent efficacy in multiple mouse tumor models, including in the MDA-MB-231 triple-negative breast cancer orthotopic model.

These data provide the preclinical rationale for further evaluation of Ti-104, Ti-176 and Ti-108 as breast cancer treatments.

Citation Format: Karr RW, Liu K, Hiebsch R, Capoccia B, Donio M, Crowley K, Puro R, Chanda S, Manning P. Development of humanized anti-CD47 monoclonal antibodies with differentiated functional profiles [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-10-15.

Systematic effects from an ambient-temperature, continuously rotating half-wave plate

We present an evaluation of systematic effects associated with a continuously rotating, ambient-temperature half-wave plate (HWP) based on two seasons of data from the Atacama B-Mode Search (ABS) experiment located in the Atacama Desert of Chile. The ABS experiment is a microwave telescope sensitive at 145 GHz. Here we present our in-field evaluation of celestial (Cosmic Microwave Background (CMB) plus galactic foreground) temperature-to-polarization leakage. We decompose the leakage into scalar, dipole, and quadrupole leakage terms. We report a scalar leakage of ∼0.01%, consistent with model expectations and an order of magnitude smaller than other CMB experiments have been reported. No significant dipole or quadrupole terms are detected; we constrain each to be <0.07% (95% confidence), limited by statistical uncertainty in our measurement. Dipole and quadrupole leakage at this level lead to systematic error on r ≲ 0.01 before any mitigation due to scan cross-linking or boresight rotation. The measured scalar leakage and the theoretical level of dipole and quadrupole leakage produce systematic error of r < 0.001 for the ABS survey and focal-plane layout before any data correction such as so-called deprojection. This demonstrates that ABS achieves significant beam systematic error mitigation from its HWP and shows the promise of continuously rotating HWPs for future experiments.

In-patient diabetes care: the impact of diabetes outreach team on long-term glycaemic control

AIM

Our aim is to assess the impact of inpatient diabetes services on glycaemic control in patient with diabetes admitted to a secondary care hospital in UK.

METHODS

We performed a retrospective analysis of all diabetes mellitus (DM) in-patients who were seen by our Diabetes Outreach Team from June 2007 to December 2010. Those with an admission diagnosis of hypoglycaemia were excluded. Blood samples including HbA1c at the initial visit and subsequent outpatient follow-up at 3-6 months were collected. Patients admitted with newly diagnosed diabetes were analysed separately.

RESULTS

In total 2002 patient data were captured. 778 patients were eliminated initially because of failure to attend follow-up clinic, lack of follow-up HbA1c data, and because of planned discharge to the community. Complete blood samples were available for 1224 patients. Of this, 235 patients (19.2% of those with complete data) were analysed separately as their primary diagnosis was hypoglycaemia. In the remaining 989 patients, 31 (3.1%) new onset Type 1 DM patients and 91 (9.2%) new onset Type 2 patients were analysed separately. In patients with known DM (n = 867) HbA1c improved from 75 mmol/mol (9.0% ± 2.39) to 69 mmol/mol (8.46% ± 2.0) (p < 0.001). In the newly diagnosed Type 1 DM (n = 31) patients HbA1c improved from 114 mmol/mol (12.55% ± 2.27) to 58 mmol/mol (7.43% ± 2.05) (p < 0.001). In the newly diagnosed Type 2 DM (n = 91) patients HbA1c improved from 93 mmol/mol (10.70% ± 3.04) to 56 mol/mol (7.29% ± 1.74) (p < 0.001). In those who presented with hypoglycaemia (n = 235) HbA1c changed from 58 mmol/mol (7.48% ± 1.59) to 59 mmol/mol (7.59% ± 1.57) (p = 0.2).

CONCLUSION

By providing a comprehensive care, structured education and appropriate intervention through our Diabetes Outreach Team, we have shown a significant reduction in HbA1c for recently hospitalised patients.

Transport of Organic Solutes through Amorphous Teflon AF Films

Fluorous media have great potential for selective extraction (e.g., as applied to organic synthesis). Fluorous polymer films would have significant advantages in fluorous separations. Stable films of Teflon AF 2400 were cast from solution. Films appear defect-free (SEM; AFM). Rigid aromatic solutes are transported (from chloroform solution to chloroform receiving phase) in a size-dependent manner (log permeability is proportional to -0.0067 times critical volume). Benzene's permeability is about 2 orders of magnitude higher than in comparable gas-phase experiments. The films show selectivity for fluorinated solutes in comparison to the hydrogen-containing control. Transport rates are dependent on the solvent making up the source and receiving phases. The effect of solvent is, interestingly, not due to changes in partition ratio, but rather it is due to changes in the solute diffusion coefficient in the film. Solvents plasticize the films. A less volatile compound, -COOH-terminated poly(hexafluoropropylene oxide) (4), plasticizes the films (T(g) = -40 degrees C). Permeabilities are decreased in comparison to 4-free films apparently because of decreased diffusivity of solutes. The slope of dependence of log permeability on critical volume is not changed, however.

Parents explain more often to boys than to girls during shared scientific thinking

Young children's everyday scientific thinking often occurs in the context of parent-child interactions. In a study of naturally occurring family conversation, parents were three times more likely to explain science to boys than to girls while using interactive science exhibits in a museum. This difference in explanation occurred despite the fact that parents were equally likely to talk to their male and female children about how to use the exhibits and about the evidence generated by the exhibits. The findings suggest that parents engaged in informal science activities with their children may be unintentionally contributing to a gender gap in children's scientific literacy well before children encounter formal science instruction in grade school.

A rapid method to detect dried saliva stains swabbed from human skin using fluorescence spectroscopy

Saliva on skin is important in forensic trace evidence. If areas where saliva is present can be outlined, this may lead to DNA analysis and identification. This study describes a rapid and non-destructive method to detect dried saliva on the surface of the skin by fluorescence spectroscopy. Eighty-two volunteers deposited samples of their own saliva on the skin of their ventral forearm. A control sample of water was deposited at three different sites on the contralateral arm. Saliva and water control were then allowed to air-dry. Swab samples were taken from dried saliva and control sites and were dissolved in 0.1M KCl solution. Emission spectra were obtained from the solution and were characterized by a principal maximum at 345-355nm with excitation at 282nm. The fluorescence emission intensity was greater than background readings obtained from the control swab site in 80 of 82 volunteers (approximately 97.6%). The fluorescence profile of saliva samples were similar to those obtained from aqueous samples of pure amylase and tryptophan, an endogenous fluorophore in alpha-amylase. The presence of an emission peak at 345-355nm with excitation at 282nm could provide a strong presumptive indication of saliva deposition.

Pulmonary tuberculosis in pregnancy

Tuberculosis (TB) was once a formidable public health hazard but is now less feared because of the development of an armamentarium of effective drugs. The incidence of TB had been declining for decades until recently when the number of cases of TB began to rise. The most obvious reasons for this trend were the rising rate of human immunodeficiency virus infection and the development of multiple drug-resistant TB. The largest percentage increase in TB cases occurred among persons 25 to 44 years of age; many of them are women. A number of these women will first be diagnosed with TB infection during pregnancy. It is important for the clinician to be aware of the impact of TB on this population. Patients must be screened as recommended by the Centers for Disease Control and Prevention because it is important to quickly diagnose TB. Prompt and effective therapy will benefit the mother and the neonate. This article reviews the diagnosis, prevention, and treatment regimens of TB in pregnancy, as well as the effects on the HIV patient, the neonate, and breastfeeding. Prompt recognition and treatment of TB infection will ensure that the rates of TB cases decline.

Explanation and generalization in young children's strategy learning

Children often learn new problem-solving strategies by observing examples of other people's problem-solving. When children learn a new strategy through observation and also explain the new strategy to themselves, they generalize the strategy more widely than children who learn a new strategy but do not explain. We tested three hypothesized mechanisms through which explanations might facilitate strategy generalization: more accurate recall of the new strategy's procedures; increased selection of the new strategy over competing strategies; or more effective management of the new strategy's goal structure. Findings supported the third mechanism: Explanations facilitated generalization through the creation of novel goal structures that enabled children to persist in use of the new strategy despite potential interference from competing strategies. The facilitative effect of explanation did vary with children's age and did not vary between explanations children created by themselves versus explanations they learned from the experimenter.

Analog classroom assessment of Adderall in children with ADHD

OBJECTIVE

This was a randomized, double-blind, crossover study of 30 children with attention-deficit/hyperactivity disorder (ADHD) that evaluated the time course effects of four doses of Adderall (5, 10, 15, and 20 mg), an inactive control (placebo), and a positive control (clinical dose of methylphenidate).

METHOD

For each treatment condition, a capsule was administered in the morning and assessments were performed in an analog classroom setting every 1.5 hours across the day. Subjective (teacher ratings of deportment and attention) and objective (scores on math tests) measures were obtained for each classroom session, and these measures were used to evaluate time-response and dose response effects of Adderall.

RESULTS

For doses of Adderall greater than 5 mg, significant time course effects were observed. Rapid improvements on teacher ratings and math performance were observed by 1.5 hours after administration, and these effects dissipated by the end of the day. The specific pattern of time course effects depended on dose: the time of peak effects and the duration of action increased with dose of Adderall.

CONCLUSIONS

This documentation of efficacy in a controlled study supports the addition of Adderall to the armamentarium of psychotropic medications for the treatment of ADHD. The differences in time-response patterns of Adderall and methylphenidate may help tailor treatment to meet specific clinical needs of different children with ADHD.

Studies of aggressive behaviour in schizophrenia: is there a response bias?

Of 73 patients who met selection criteria to enter into a study on aggressive behaviour in schizophrenia, 11 patients (15.1%) did not participate. The participants and non-participants were similar in age, gender ratio and proportion who had aggressive behaviour. The participants, however, had a longer duration of illness, a longer duration of current admission, were more likely to suffer from residual schizophrenia, but less likely to suffer from disorganized schizophrenia and were less severely ill than the non-participants. These results indicate the need, in studies of aggressive behaviour in schizophrenia, to consider non-response bias as a confounding variable.

Violence in schizophrenia: role of hallucinations and delusions

The study examines the relationship between hallucinations/delusions and violent behaviour in a sample of long-stay inpatients with chronic schizophrenia. Thirty-one subjects defined as violent and meeting DSM-111-R criteria for schizophrenia were compared with 31 matched non-violent schizophrenia patients with respect to detailed phenomenologies of auditory hallucinations using the Mental Health Research Institute Unusual Perceptions Schedule (Carter and Copolov, 1993; Carter et al., 1995) and delusions using the Maudsley Assessment of Delusions Schedule (Taylor et al., 1994). Patients in the violent groups were significantly more likely to experience negative emotions, tone and content related to their voices than those in the non-violent group, whilst patients in the non-violent group were more likely to experience positive emotions, tone and content related to their voices. Patients in the non-violent group were significantly more likely to report success in coping with their voices. There was no association between command hallucinations and violent behaviour. Patients in the violent group were more likely to hold persecutory delusional beliefs than those in the non-violent group, while patients in the non-violent group were likely to hold grandiose delusions than those in the violent group. Patients in the violent group were also more likely to report that the delusion made them feel angry, while those in the non-violent group were more likely to report that the delusion made them feel elated. The results suggest specific aspects of the phenomenologies of hallucinations and delusions that should be clinically assessed to determine the likelihood of violence as a result of such psychotic symptoms.

Aggressive behaviour in schizophrenia: role of state versus trait factors

The objective of this article was to elucidate the relative importance of state vs. trait factors in determining aggressive behaviour in schizophrenia. Thirty-one aggressive schizophrenia patients in rehabilitation wards were compared with 31 matched non-aggressive patients with respect to their psychopathology, phenomenologies of hallucinations and delusions, neuroleptic motor side effects, history of aggression and personality traits. Significant differences between the two groups were found in relation to psychopathology, affective responses to hallucinations/delusions, history of aggression and personality traits, but there were no significant differences regarding neuroleptic motor side effects. The effects of history of aggression as well as personality traits were independent of and similar to the total level of psychopathology, but were much smaller when compared to those of negative affective responses to hallucinations/delusions.

Reduction in tuberculin skin-test conversions among medical house staff associated with improved tuberculosis infection control practices

OBJECTIVE

To assess the efficacy of an infection control program as measured by tuberculin skin-test (TST) conversion rates in medical house staff.

DESIGN

Observational study.

SETTING

University-based hospital in New York City serving a large indigent population.

PARTICIPANTS

Medical house staff.

INTERVENTIONS

TST conversions were measured every 6 months in medical house staff from June 1992 to June 1994. Compliance with the isolation policy was measured by identifying room locations 24 hours after admission of patients who had Mycobacterium tuberculosis recovered from respiratory specimens.

RESULTS

The TST conversion rate decreased from 5.8 to 0, 2.3, and 0 per 100 person years of exposure in successive 6-month periods. The estimated annual TST conversion rate among interns fell from 7 per 100 person years in June 1992 to 0 per 100 person years in June 1993 and 0 per 100 person years in June 1994 (P < .029). The proportion of patients with pulmonary tuberculosis who were isolated in negative-pressure rooms increased from 38% to 75% over the study period (P < .01).

CONCLUSION

Development of a multifaceted infection control program can decrease the risk of nosocomial tuberculosis infection in medical house staff.

Is repeat laparotomy of value in patients with suspected intra-abdominal sepsis in the intensive care unit?

The management of patients with suspected post laparotomy intra-abdominal sepsis poses a major therapeutic challenge to clinicians. The mortality is high and the optimal interventional modality remains ill-defined. We define the incidence, diagnostic methodology, pre- and postoperative findings and outcome of patients going from the intensive care unit for a repeat laparotomy in search of abdominal sepsis over a one year period. Fifteen patients were included with an overall mortality of 60 percent. In 6 cases more than one relaparotomy was performed with a mortality of 50 percent. Sepsis was found in 14 of the 15 cases with a mortality of 57 percent and the patient with a normal relaparotomy died. The primary surgery was elective in 26 percent of cases and the mortality was 50 percent. All the non-survivors required mechanical ventilation, inotropic support and continuous veno-veno haemodialysis while the survivors required less organ support. Radiological assessment (ultrasound scan and CT scan) were no better at predicting an abnormal relaparotomy than clinical assessment. Higher mortality rates were associated with increasing age and multi-system organ failure (p < 0.05).

Aggressive behaviour in schizophrenia: the role of psychopathology

OBJECTIVE

The aim of this study was to determine the psychopathological correlates of aggressive behaviour in schizophrenia.

METHOD

Thirty-one aggressive patients in rehabilitation wards meeting DSM-III-R criteria for schizophrenia were compared with 31 matched non-aggressive patients in relation to their psychopathology using the Clinical Global Index (CGI), Positive and Negative Symptoms scale (PANSS) and the Montgomery-Asberg Depression Rating Scale.

RESULTS

The aggressive group had significantly higher CGI, positive symptom, negative symptom, general psychopathology and total PANSS scores than the non-aggressive group. The two groups could be distinguished by three sets of symptoms: symptoms with verbal or/and physical aggression as part of their definition; symptoms suggesting frontal lobe impairment; and excitement. The two groups did not differ in their level of depressive symptomatology.

CONCLUSIONS

The aggressive group were overall more ill than the non-aggressive group, and the former could be distinguished from the latter by certain aspects of their psychopathology.

Aggressive behaviour and platelet 3H-paroxetine binding in schizophrenia

Forty schizophrenic patients were included in a study of the relationship between serotonin function as measured by 3H-paroxetine binding to platelet membranes and aggressive behaviour. Patients classified as either aggressive or non-aggressive were paired by age, sex and duration of illness. 3H-Paroxetine binding variations were avoided by taking samples for each pair between 09:00 and 11:00 h, within 4 days of each other, and by assaying pair of samples together. The mean Kd for the aggressive group was 0.193 +/- 0.126 nM and the mean Kd for the non-aggressive group was 0.176 +/- 0.164 nM. The mean Bmax for the aggressive group was 1451 +/- 386 fmol/mg protein while the mean for the non-aggressive group was 1549 +/- 375 fmol/mg protein. There was no significant difference between the groups for either parameter, Kd or Bmax. There were no significant correlations between psychopathology rating including positive and negative symptoms, depression, suicidal thoughts, impulse control, as well as both past and present history of aggression, hostility and irritability traits, psychopathic deviance and either Bmax and Kd. This study finds no relationship between aggressive behaviour and peripheral serotonin function as measured by 3H-paroxetine binding to platelet membranes.

Acute renal failure in orthotopic liver transplantation

Acute renal failure (ARF) is a frequent complication of orthotopic liver transplantation (OLT) and is a major cause of mortality and morbidity. We report the incidence, management and outcome of ARF in OLT patients during the first year of a liver transplant programme.

Formularies in integrated health systems: Sharp HealthCare

Formulary management implications are described for a California health system comprising 7 hospitals, 4 skilled-nursing centers, 22 medical clinics, 8 urgent care facilities, and a health maintenance organization. Sharp HealthCare serves nearly one million people in the San Diego area. A single institutional care division (ICD) pharmacy service has been created under the guidance of a steering committee comprising a pharmacy operations coordinator and a staff pharmacist from each site, the system pharmacy director, the system senior pharmacy information systems specialist, and the system senior clinical pharmacy specialist. Operations at each site are overseen by an operations coordinator instead of a pharmacy director. Functional teams reporting to the steering committee are standardized pharmacy processes, including formulary management; this is particularly important because the ICD has pharmacists and nurse per diem pools. Until 1995, formularies were independently managed at each site. Now, one system formulary is being developed. Standard policies and procedures, a nonformulary drug request form, and a monograph format have been completed. The hospitals' autonomous medical staffs have thus far elected to retain individual pharmacy and therapeutics (P&T) committees but approved a revamped formulary review process and system-wide P&T subcommittees. The computer system is being enhanced so that pharmacists will have access to applicable P&T committee-approved guidelines for drug use. Since vendors were advised that the system is establishing one formulary, Sharp has been able in some cases to achieve better pricing than it previously could through its purchasing group.

Identification of three separate binding sites on SHK toxin, a potent inhibitor of voltage-dependent potassium channels in human T-lymphocytes and rat brain

Eighteen synthetic analogs of ShK toxin, a thirty-five residue K channel blocker derived from the sea anemone Stichodactyla helianthus, were prepared in order to identify functionally important residues. CD spectra of sixteen of the analogs were virtually identical with the spectrum of wild-type toxin, indicating that the conformations were not affected by the substitutions. A conserved residue, Lys22, is essential for ShK binding to rat brain K channels which are primarily of the Kv1.2 type. However, a cationic side chain at position 22 is not essential for binding to the human Jurkat T-lymphocyte Kv1.3 channel. While decreasing bulkiness at this position affected toxin affinity for the brain K channels, increasing bulkiness decreased toxin affinity for both brain and lymphocyte K channels. In contrast to the rat brain channels, ShK binding to Kv1.3 was sensitive to substitution at Lys9 and Arg11.

Formularies in integrated health systems: Sharp HealthCare

Formulary management implications are described for a California health system consisting of 7 hospitals, 4 skilled-nursing centers, 22 medical clinics, 8 urgent care facilities, and a health maintenance organization. Sharp HealthCare serves nearly 1 million people in the San Diego area. A single institutional care division (ICD) pharmacy service has been created under the guidance of a steering committee consisting of a pharmacy operations coordinator and a staff pharmacist from each site, the system pharmacy director, the system senior pharmacy information systems specialists, and the system senior clinical pharmacy specialist. Operations at each site are overseen by an operations coordinator instead of a pharmacy director. Functional teams reporting to the steering committee are standardizing pharmacy processes, including formulary management; this is particularly important because the ICD has pharmacist and nurse per diem pools. Until 1995, formularies were independently managed at each site. Now, one system formulary is being developed. Standard policies and procedures, a nonformulary drug request form, and a monograph format have been completed. The hospitals' autonomous medical staffs have thus far elected to retain individual pharmacy and therapeutics (P&T) committees but approved a revamped formulary review process and systemwide P&T subcommittees. The computer system is being enhanced so that pharmacists anywhere in one of the hospitals will have access to applicable P&T committee-approved guidelines for drug use. Since vendors were advised that the system is establishing one formulary, Sharp has been able in some cases to achieve better pricing than it previously could through its purchasing group. Drug use is influenced by each site's pharmacy and therapeutics committee. The ideal, however, is to have this responsibility consolidated in a single systemwide committee.

Constraints on learning in nonprivileged domains

Constraints on learning, rather than being unique to evolutionarily privileged domains, may operate in nonprivileged domains as well. Understanding of the goals that strategies must meet seems to play an especially important role in these domains in constraining the strategies that are generated and in allowing children to evaluate strategies even before they use them. The present experiments showed that children can use their conceptual understanding to accurately evaluate strategies that they not only do not yet use but that are more conceptually advanced than the strategies they do use. In Experiment 1, 5-year-olds who did not yet use the min strategy for adding numbers judged it to be smarter than an equally novel illegitimate strategy, and to be just as smart as their typical strategy of counting from one. In Experiment 2, 9-year-olds who did not yet use the forking strategy to play tic-tac-toe judged it to be even smarter than their own win/block approach. The results demonstrated a large number of commonalities between the functioning of constraints in privileged and nonprivileged domains, as well as suggesting some possible differences.

Schwannoma (neurilemoma) with malignant transformation. A rare, distinctive peripheral nerve tumor

Malignant transformation of a schwannoma (neurilemoma) is an exceedingly rare event. We describe two cases with such change and review the reported purported examples. The tumors in our patients involved a finger and pelvis. Sex, age, and clinical follow-up were available for only the second case, involving a 31-year-old man who died with recurrent and metastatic tumor. Seven acceptable cases were found in the literature. Analysis of the nine cases of schwannoma with malignant transformation showed no sex predilection, but revealed a tumor differing significantly from conventional malignant peripheral nerve sheath tumors. The mean age (56 years) was two decades older, no patient had neurofibromatosis, in four cases there was a years-long history of an antecedent mass, and in none of the cases was the malignant component an interlacing, fasciculated spindle-cell tumor. Rather, the malignant component was commonly purely epithelioid (seven of nine cases). In the two other cases, cells of the malignant component had neuroepithelial features. The prognosis for patients with schwannomas undergoing malignant change is poor. Five of eight patients with follow-up (62%) died of disease with either residual (one patient) or metastatic tumor (four patients).

The microgenetic method: A direct means for studying cognitive development

Progress in understanding cognitive developmental change mechanisms requires methods that yield detailed data about particular changes. The microgenetic method is an approach that can yield such data. It involves (a) observations of individual children throughout the period of the change, (b) a high density of observations relative to the rate of change within that period, and (c) intensive trial-by-trial analyses intended to infer the processes that gave rise to the change. This approach can illuminate both qualitative and quantitative aspects of change, indicate the conditions under which changes occur, and yield otherwise unobtainable information about short-lived transition strategies. The cost in time and effort of such studies is often high, but the value of the information about change can more than justify the cost.

Diuretics after transurethral prostatectomy: a double-blind controlled trial comparing frusemide and mannitol

Mannitol and frusemide were compared in a randomized, controlled, double-blind trial for their effects in promoting diuresis after prostatectomy and on indices of water intoxication. The drugs had comparable diuretic effects. Sodium loss was greater with frusemide, contributing to sodium depletion after operation. Administration of frusemide was associated with more frequent need for i.v. volume expansion after operation. Plasma osmolality was greater with mannitol (289 (SD 4.2 mosmol kg-1 at 1 h after operation and 285 (5.3) mosmol kg-1 at 4 h after operation) than with frusemide (282 (7.1) mosmol kg-1 and 279 (6.7) mosmol kg-1, respectively) (P less than 0.05). Plasma concentration of sodium was significantly greater with mannitol (136.9 (3.1) mmol litre-1) than with frusemide (134.4 (2.8) mmol litre-1) only on the morning after surgery (P less than 0.05). Mannitol is an effective alternative to frusemide in inducing diuresis after prostatectomy, and may protect against water intoxication.

Septicaemia and the prevention of multiorgan failure--the intensive care perspective

Septicaemia frequently presents without "classic" signs of infection--tachypnoea, hypotension and confusion are the commonest features. The mortality rate is 40 to 80% and in intensive care units, septicaemia accounts for 70% of all deaths. Despite the use of antimicrobial drugs to which the offending organism is sensitive, patients are still dying. Effects on distant organ systems are due to "Mediators". "Microvascular Failure" resulting in tissue hypoxia is the unifying hypothesis of multiple organ failure in septicaemia. Mortality is correlated with the number of organ system failures. Supportive management is aimed at prevention of organ failure--manipulation of the circulation being the central key. Intravascular volume expansion, vasoactive drugs, mechanical ventilation and invasive monitoring are the means. Antimicrobial therapy must be guided by 'best guess' approach with multiple agents until isolation of the offending organism can recommend specific therapy. Aggressive surgical drainage or excision, is particularly applicable in abdominal sepsis. Several adjunctive therapies aimed at mediators of sepsis, are as yet experimental.

Serum concentrations of prilocaine following retrobulbar block

Retrobulbar block for eye surgery is associated with adverse reactions. We performed retrobulbar block in 10 patients using prilocaine (Citanest) and found mean (SD) peak serum concentrations of 851 (165.6) ng ml-1 (range 540-1100 mg ml-1). Peak serum concentrations occurred 3-7 min after the end of administration of the block, and in all cases were less than those associated with toxicity.

Barbiturate anesthetics inhibit thromboxane-, potassium-, but not angiotensin-induced pulmonary vasoconstriction

Administration of the oxidant lipid peroxide tertiary butyl hydroperoxide (t-bu-OOH) in the isolated rabbit lung leads to acute pulmonary vasoconstriction, which is caused by the synthesis of thromboxane. The inhalational anesthetics, halothane, nitrous oxide, and cyclopropane, markedly enhance t-bu-OOH-induced pulmonary vasoconstriction and thromboxane production. The effects of the intravenous (iv) barbiturates thiopental and pentobarbital on t-bu-OOH-induced vasoconstriction were studied. Thiopental completely and pentobarbital partially blocked t-bu-OOH-induced vasoconstriction. Thiopental inhibited t-bu-OOH-induced synthesis of thromboxane and prostacyclin but pentobarbital did not. This inhibitory action of thiopental may be due to its antioxidant properties because similar inhibition has been observed of t-bu-OOH-induced thromboxane production with the antioxidants, vitamin E, or butylated hydroxylanisole. Thiopental and pentobarbital also inhibited the vasoconstriction induced by a thromboxane analog, epoxymethano prostaglandin H2 (U46619). Finally, both barbiturates partially inhibited the pulmonary vasoconstriction caused by potassium chloride, which requires calcium entry, but they did not inhibit the constriction caused by angiotensin II, which does not require calcium entry. These results suggest that pentobarbital and thiopental may block pulmonary vasoconstriction by inhibiting calcium entry.