The NLRP3 inflammasome is essential for IL-18 production in a murine model of macrophage activation syndrome

Hyperinflammatory disease is associated with an aberrant immune response resulting in cytokine storm. One such instance of hyperinflammatory disease is known as macrophage activation syndrome (MAS). The pathology of MAS can be characterised by significantly elevated serum levels of interleukin (IL)-18 and interferon (IFN)-γ. Given the role for IL-18 in MAS, we sought to establish the role of inflammasomes in the disease process. Using a murine model of CpG-DNA induced MAS, we discovered that the expression of the NLRP3 inflammasome was increased and correlated with IL-18 production. Inhibition of the NLRP3 inflammasome, or downstream caspase-1, prevented MAS-mediated upregulation of plasma IL-18 but interestingly did not alleviate key features of hyperinflammatory disease including hyperferritinaemia and splenomegaly. Furthermore IL-1 receptor blockade with IL-1Ra did not prevent the development of CpG-induced MAS, despite being clinically effective in the treatment of MAS. These data demonstrate that in the development of MAS, the NLRP3 inflammasome was essential for the elevation in plasma IL-18, a key cytokine in clinical cases of MAS, but was not a driving factor in the pathogenesis of CpG-induced MAS.

Discovery of an inhibitor of DNA-driven inflammation that preferentially targets the AIM2 inflammasome

Inflammation driven by DNA sensors is now understood to be important to disease pathogenesis. Here, we describe new inhibitors of DNA sensing, primarily of the inflammasome forming sensor AIM2. Biochemistry and molecular modeling has revealed 4-sulfonic calixarenes as potent inhibitors of AIM2 that likely work by binding competitively to the DNA-binding HIN domain. Although less potent, these AIM2 inhibitors also inhibit DNA sensors cGAS and TLR9 demonstrating a broad utility against DNA-driven inflammatory responses. The 4-sulfonic calixarenes inhibited AIM2-dependent post-stroke T cell death, highlighting a proof of concept that the 4-sulfonic calixarenes could be effective at combating post-stroke immunosuppression. By extension, we propose a broad utility against DNA-driven inflammation in disease. Finally, we reveal that the drug suramin, by virtue of its structural similarities, is an inhibitor of DNA-dependent inflammation and propose that suramin could be rapidly repurposed to meet an increasing clinical need.

Phenolic and quinone methide nor-triterpenes as selective NLRP3 inflammasome inhibitors

Dysregulated inflammasome activity, particularly of the NLRP3 inflammasome, is associated with the development of several inflammatory diseases. The study of molecules directly targeting NLRP3 is an emerging field in the discovery of new therapeutic compounds for the treatment of inflammatory disorders. Friedelane triterpenes are biologically active phytochemicals having a wide range of activities including anti-inflammatory effects. In this work, we evaluated the potential anti-inflammatory activity of phenolic and quinonemethide nor-triterpenes (1-11) isolated from Maytenus retusa and some semisynthetic derivatives (12-16) through inhibition of the NLRP3 inflammasome in macrophages. Among them, we found that triterpenes 6 and 14 were the most potent, showing markedly reduced caspase-1 activity, IL-1β secretion (IC₅₀ = 1.15 µM and 0.19 µM, respectively), and pyroptosis (IC₅₀ = 2.21 µM and 0.13 µM, respectively). Further characterization confirmed their selective inhibition of NLRP3 inflammasome in both canonical and non-canonical activation pathways with no effects on AIM2 or NLRC4 inflammasome activation.

Disruptions in endocytic traffic contribute to the activation of the NLRP3 inflammasome

Inflammation driven by the NLRP3 inflammasome is coordinated through multiple signaling pathways and is regulated by subcellular organelles. Here, we tested the hypothesis that NLRP3 senses disrupted endosome trafficking to trigger inflammasome formation and inflammatory cytokine secretion. NLRP3-activating stimuli disrupted endosome trafficking and triggered localization of NLRP3 to vesicles positive for endolysosomal markers and for the inositol lipid PI4P. Chemical disruption of endosome trafficking sensitized macrophages to the NLRP3 activator imiquimod, driving enhanced inflammasome activation and cytokine secretion. Together, these data suggest that NLRP3 can sense disruptions in the trafficking of endosomal cargoes, which may explain in part the spatial activation of the NLRP3 inflammasome. These data highlight mechanisms that could be exploited in the therapeutic targeting of NLRP3.

Looking into the IL-1 of the storm: are inflammasomes the link between immunothrombosis and hyperinflammation in cytokine storm syndromes?

Inflammasomes and the interleukin (IL)-1 family of cytokines are key mediators of both inflammation and immunothrombosis. Inflammasomes are responsible for the release of the pro-inflammatory cytokines IL-1β and IL-18, as well as releasing tissue factor (TF), a pivotal initiator of the extrinsic coagulation cascade. Uncontrolled production of inflammatory cytokines results in what is known as a "cytokine storm" leading to hyperinflammatory disease. Cytokine storms can complicate a variety of diseases and results in hypercytokinemia, coagulopathies, tissue damage, multiorgan failure, and death. Patients presenting with cytokine storm syndromes have a high mortality rate, driven in part by disseminated intravascular coagulation (DIC). While our knowledge on the factors propagating cytokine storms is increasing, how cytokine storm influences DIC remains unknown, and therefore treatments for diseases, where these aspects are a key feature are limited, with most targeting specific cytokines. Currently, no therapies target the immunothrombosis aspect of hyperinflammatory syndromes. Here we discuss how targeting the inflammasome and pyroptosis may be a novel therapeutic strategy for the treatment of hyperinflammation and its associated pathologies.

Itaconate and fumarate derivatives inhibit priming and activation of the canonical NLRP3 inflammasome in macrophages

The NLRP3 inflammasome is a multiprotein complex that regulates caspase-1 activation and subsequent interleukin (IL)-1β and IL-18 release from innate immune cells in response to infection or injury. Derivatives of the metabolites itaconate and fumarate, dimethyl itaconate (DMI), 4-octyl itaconate (4OI) and dimethyl fumarate (DMF) limit both expression and release of IL-1β following NLRP3 inflammasome activation. However, the direct effects of these metabolite derivatives on NLRP3 inflammasome responses require further investigation. Using murine bone marrow-derived macrophages, mixed glia and organotypic hippocampal slice cultures (OHSCs), we demonstrate that DMI, 4OI and DMF pretreatments inhibit pro-inflammatory cytokine production in response to lipopolysaccharide (LPS), as well as inhibit subsequent NLRP3 inflammasome activation induced by nigericin. DMI, 4OI, DMF and monomethyl fumarate (MMF), another fumarate derivative, also directly inhibited biochemical markers of NLRP3 activation in LPS-primed macrophages, mixed glia, OHSCs and human macrophages in response to nigericin and imiquimod, including ASC speck formation, caspase-1 activation, gasdermin D cleavage and IL-1β release. DMF, an approved treatment of multiple sclerosis, as well as DMI, 4OI and MMF, inhibited NLRP3 activation in macrophages in response to lysophosphatidylcholine, which is used to induce demyelination, suggesting a possible mechanism for DMF in multiple sclerosis through NLRP3 inhibition. The derivatives also reduced pro-IL-1α cleavage in response to the calcium ionophore ionomycin. Together, these findings reveal the immunometabolic regulation of both the priming and activation steps of NLRP3 activation in macrophages. Furthermore, we highlight itaconate and fumarate derivatives as potential therapeutic options in NLRP3- and IL-1α-driven diseases, including in the brain.

LRRC8A is dispensable for a variety of microglial functions and response to acute stroke

Microglia, resident brain immune cells, are critical in orchestrating responses to central nervous system (CNS) injury. Many microglial functions, such as phagocytosis, motility and chemotaxis, are suggested to rely on chloride channels, including the volume‐regulated anion channel (VRAC), but studies to date have relied on the use of pharmacological tools with limited specificity. VRAC has also been proposed as a drug target for acute CNS injury, and its role in microglial function is of considerable interest for developing CNS therapeutics. This study aimed to definitively confirm the contribution of VRAC in microglia function by using conditional LRRC8A‐knockout mice, which lacked the essential VRAC subunit LRRC8A in microglia. We demonstrated that while VRAC contributed to cell volume regulation, it had no effect on phagocytic activity, cell migration or P2YR12‐dependent chemotaxis. Moreover, loss of microglial VRAC did not affect microglial morphology or the extent of ischemic damage following stroke. We conclude that VRAC does not critically regulate microglial responses to brain injury and could be targetable in other CNS cell types (e.g., astrocytes) without impeding microglial function. Our results also demonstrate a role for VRAC in cell volume regulation but show that VRAC is not involved in several major cellular functions that it was previously thought to regulate, and point to other, alternative mechanisms of chloride transport in innate immunity.

LRRC8A is essential for hypotonicity-, but not for DAMP-induced NLRP3 inflammasome activation

The NLRP3 inflammasome is a multi-molecular protein complex that converts inactive cytokine precursors into active forms of IL-1β and IL-18. The NLRP3 inflammasome is frequently associated with the damaging inflammation of non-communicable disease states and is considered an attractive therapeutic target. However, there is much regarding the mechanism of NLRP3 activation that remains unknown. Chloride efflux is suggested as an important step in NLRP3 activation, but which chloride channels are involved is still unknown. We used chemical, biochemical, and genetic approaches to establish the importance of chloride channels in the regulation of NLRP3 in murine macrophages. Specifically, we identify LRRC8A, an essential component of volume-regulated anion channels (VRAC), as a vital regulator of hypotonicity-induced, but not DAMP-induced, NLRP3 inflammasome activation. Although LRRC8A was dispensable for canonical DAMP-dependent NLRP3 activation, this was still sensitive to chloride channel inhibitors, suggesting there are additional and specific chloride sensing and regulating mechanisms controlling NLRP3.

Mechanisms of NLRP3 priming in inflammaging and age related diseases

The NLRP3 inflammasome is a vital part of the innate immune response, whilst its aberrant activation drives the progression of a number of non-communicable diseases. Thus, NLRP3 inflammasome assembly must be tightly controlled at several checkpoints. The priming step of NLRP3 inflammasome activation is associated with increased NLRP3 gene expression, as well as post-translational modifications that control NLRP3 levels and licence the NLRP3 protein for inflammasome assembly. Increasing life expectancy in modern society is accompanied by a growing percentage of elderly individuals. The process of aging is associated with chronic inflammation that drives and/or worsens a range of age related non-communicable conditions. The NLRP3 inflammasome is known to contribute to pathological inflammation in many settings, but the mechanisms that prime NLRP3 for activation throughout aging and related co-morbidities have not been extensively reviewed. Here we dissect the biochemical changes that occur during aging and the pathogenesis of age related diseases and analyse the mechanisms by which they prime the NLRP3 inflammasome, thus exacerbating inflammation.

Atheroprone flow activates inflammation via endothelial ATP-dependent P2X7-p38 signalling

Objective

Atherosclerosis is a focal disease occurring at arterial sites of disturbed blood flow that generates low oscillating shear stress. Endothelial inflammatory signalling is enhanced at sites of disturbed flow via mechanisms that are incompletely understood. The influence of disturbed flow on endothelial adenosine triphosphate (ATP) receptors and downstream signalling was assessed.

Methods and results

Cultured human endothelial cells were exposed to atheroprotective (high uniform) or atheroprone (low oscillatory) shear stress for 72 h prior to assessment of ATP responses. Imaging of cells loaded with a calcium-sensitive fluorescent dye revealed that atheroprone flow enhanced extracellular calcium influx in response to 300 µM 2'(3')-O-(4-Benzoylbenzoyl) adenosine-5'-triphosphate. Pre-treatment with pharmacological inhibitors demonstrated that this process required purinergic P2X7 receptors. The mechanism involved altered expression of P2X7, which was induced by atheroprone flow conditions in cultured cells. Similarly, en face staining of the murine aorta revealed enriched P2X7 expression at an atheroprone site. Functional studies in cultured endothelial cells showed that atheroprone flow induced p38 phosphorylation and up-regulation of E-selectin and IL-8 secretion via a P2X7-dependent mechanism. Moreover, genetic deletion of P2X7 significantly reduced E-selectin at atheroprone regions of the murine aorta.

Conclusions

These findings reveal that P2X7 is regulated by shear forces leading to its accumulation at atheroprone sites that are exposed to disturbed patterns of blood flow. P2X7 promotes endothelial inflammation at atheroprone sites by transducing ATP signals into p38 activation. Thus P2X7 integrates vascular mechanical responses with purinergic signalling to promote endothelial dysfunction and may provide an attractive potential therapeutic target to prevent or reduce atherosclerosis.

Disposition of [s]-heparin in the rat

[(35)S]-Heparin is rapidly taken up by tissues after intraperitoneal injection andrapidly degraded. Skin, aorta and lung showed an especially high affinity for[(35)S]-heparin. In these organs, as well as in adrenal gland, stomach, heart and brain,the isotope was found preponderantly as dialysable metabolite(s) of heparin. Another group of tissues (large intestine, fat, kidney and liver) was characterized by a smaller proportion of dialysable material. Tissues that showed a high affinity for exogenous heparin appeared to catabolize it rapidly. It is also noted that some of the radioactive material present in tissues after the injection of [(35)S]-heparin could come from the uptake of [(35)S]-sulphate resulting from the degradation of [(35)S]-heparin. The incorporation of [(35)S]-sulphate into the sulphomucopolysaccharides of some tissues is recorded.

Primary placement of a titanium motility post in a porous polyethylene orbital implant: animal model with quantitative assessment of fibrovascular ingrowth and vascular density

PURPOSE

To determine whether a Medpor porous polyethylene orbital implant, at the time of initial orbital implant surgery, will tolerate the insertion of a titanium screw on the anterior surface of the implant.

METHODS

Twelve New Zealand white rabbits were enucleated and implanted with a porous polyethylene orbital implant. At the time of enucleation, the porous polyethylene orbital implants were drilled, and titanium motility coupling posts were inserted. The motility coupling posts were inserted at two projection heights (2 or 4 mm) and either covered within Tenon capsule/conjunctiva (eight implants) or left exposed (four implants). Rabbits were killed at 6 or 12 weeks. Clinical tissue tolerance, histologic response to the motility coupling post, and vascular density of the porous polyethylene orbital implant were evaluated.

RESULTS

The motility coupling posts were well tolerated, and extrusion or migration of the motility coupling post did not occur. The average percentage cross-sectional area of the implant occupied by fibrovascular tissue at 6 and 12 weeks was 76.3% and 97.5%, respectively. In comparing the vascular density (number of vessels per square millimeter) in the porous polyethylene orbital implant within a 1-mm zone immediately surrounding the motility coupling post, no significant difference between this zone and the vascular density found within its entire corresponding annulus was found at either 6 or 12 weeks.

CONCLUSIONS

During the 6- and 12-week observation periods, all implanted motility coupling posts demonstrated favorable tissue tolerance and stable interfaces with surrounding tissues. The extent of fibrovascular tissue ingrowth and vascular density verify that initial screw insertion does not adversely affect the healing process after porous polyethylene orbital implant implantation. Thus, primary placement of the motility coupling post may obviate the need for a secondary surgical procedure.

Hypnosis and suggestion-based approaches to smoking cessation: an examination of the evidence

This article reviews 59 studies of hypnosis and smoking cessation as to whether the research empirically supports hypnosis as a treatment. Whereas hypnotic procedures generally yield higher rates of abstinence relative to wait-list and no-treatment conditions, hypnotic interventions are generally comparable to a variety of nonhypnotic treatments. The evidence for whether hypnosis yields outcomes superior to placebos is mixed. In short, hypnosis cannot be considered a specific and efficacious treatment for smoking cessation. Furthermore, in many cases, it is impossible to rule out cognitive/behavioral and educational interventions as the source of positive treatment gains associated with hypnotic treatments. Hypnosis cannot, as yet, be regarded as a well-established treatment for smoking cessation. Nevertheless, it seems justified to classify hypnosis as a "possibly efficacious" treatment for smoking cessation.

Hypnosis, context effects, and the recall of early autobiographical memories

This study found that attempts to recall earliest memories were strongly influenced by the testing context. It showed that a brief 3-minute self-hypnosis experience, coupled with the insinuation that hypnosis improves memory, resulted in earlier autobiographical memory reports (M = 29.5 months) than instructions for relaxation (M = 37.9 months) or counting/visualization (M = 48.9 months). Inquiries about earliest memories across 5 age ranges showed that the hypnotic context resulted in a higher proportion of participants reporting a memory at or before 12, 24, 36, 48, and 60 months of age. Nearly 40% of the "hypnotized" participants reported a memory for an event that reportedly occurred at or before 12 months of age. A brief discussion of context effects and demand characteristics associated with hypnosis and memory follows.

Removal of an infected silicone rod frontalis sling without recurrence of ptosis

We examined a child with congenital ptosis. She underwent a bilateral silicone rod frontalis sling operation. One of the slings became infected and necessitated removal. We noticed no recurrence of her ptosis after sling removal. Removal of a frontalis sling does not invariably lead to recurrence of ptosis. We hypothesize that a scar tract formed in the plane of tissue from which the sling was removed. This band of scar tissue can act as a frontalis sling to elevate the eyelid.

Hypnotizability, the dissociative experiences scale, HGSHS: A amnesia, and automatic writing: is there an association?

The present study examined whether participants (N = 112) selected on the basis of high and low dissociative ability (Dissociative Experiences Scale [DES]; Bernstein & Putnam, 1986), high and low/simulating hypnotizability (Harvard Group Scale of Hypnotic Susceptibility, Form A [HGSHS:A]; Shor & Orne, 1962), and past performance on the HGSHS:A amnesia item differentially passed an automatic writing suggestion administered during a follow-up experiment. Results from a loglinear analysis supported a single main effect for hypnotizability. Low hypnotizable, simulating participants were more than six times as likely to pass the automatic writing suggestion than high hypnotizable participants. Results found dissociation status and past performance on an ostensibly dissociative suggestion (i.e., amnesia) to be independent of passing the automatic writing suggestion. Findings are discussed in light of other research regarding the relation between the DES and hypnotizability.

"Normal pressure" pseudotumor cerebri

We present a case report of a patient with clinical features suggestive of pseudotumor cerebri (PTC), without a documented elevated measurement of intracranial pressure (ICP). Chart review was done of one patient's clinical course over a 28-month period. The patient was treated for PTC even though she never had a documented elevated ICP. Her signs and symptoms, including headache, disc edema, and visual field loss, all showed improvement with standard PTC therapy, which ultimately included optic nerve sheath fenestration (ONSF). Her presenting symptoms of clinical depression were also relieved with this treatment. PTC may present without an elevated ICP as defined by current standards. Some patients may be more susceptible to lower levels of ICP and develop this syndrome, and it may be responsive to standard PTC therapy. Further investigation may warrant that clinical depression be included as another minor symptom of PTC.

Lack of a precursor-product relationship between histamine and its metabolites in brain after histidine loading

Levels of histamine and its major metabolites in brain, tele-methylhistamine (t-MH) and tele-methylimidazoleacetic acid (t-MIAA), were measured in rat brains up to 12 h after intraperitoneal administration of L-histidine (His), the precursor of histamine. Compared with saline-treated controls, mean levels of histamine were elevated at 1 h (+102%) after a 500 mg/kg dose; levels of t-MH did not increase. Following a 1,000 mg/kg dose, mean histamine levels were increased for up to 7 h, peaked at 3 h, and returned to control levels within 12 h. In contrast, levels of t-MH showed a small increase only after 3 h; levels of t-MIAA remained unchanged after either dose. Failure of most newly formed histamine to undergo methylation, its major route of metabolism in brain, suggested that histamine was metabolized by another mechanism possibly following nonspecific decarboxylation. To test this hypothesis, other rats were injected with alpha-fluoromethylhistidine (alpha-FMHis; 75 mg/kg, i.p.), an irreversible inhibitor of specific histidine decarboxylase. Six hours after rats received alpha-FMHis, the mean brain histamine level was reduced 30% compared with saline-treated controls. Rats given His (1,000 mg/kg) 3 h after alpha-FMHis (75 mg/kg) and examined 3 h later had a higher (+112%) mean level of histamine than rats given alpha-FMHis, followed by saline. Levels of t-MH and t-MIAA did not increase. These results imply that high doses of His distort the simple precursor-product relationship between histamine and its methylated metabolites in brain. The possibility that some His may undergo nonspecific decarboxylation in brain after His loading is discussed. These findings, and other actions of His independent of histamine, raise questions about the validity of using His loading as a specific probe of brain histaminergic function.

pros-Methylimidazoleacetic acid in cerebrospinal fluid of patients with chronic schizophrenia: relationships to ratings of symptoms, ventricular brain ratios, and rates of urine excretion

Concentrations of pros-methylimidazoleacetic acid (p-MIAA) were measured in cerebrospinal fluid of 30 patients with chronic schizophrenia. Levels of p-MIAA correlated negatively with mean scores of the Psychiatric Symptom Assessment Scale for positive symptoms (r = -0.48), but not negative symptoms, and with ventricular brain ratios (r = -0.48). Patients with abnormal ventricular enlargements had much lower concentrations of p-MIAA than those with normal ventricles. These results suggest that processes that reduce accumulation of p-MIAA in CSF may be associated with increased severity of symptoms among patients with chronic schizophrenia.

The relationship between urine excretion and biogenic amines and their metabolites in cerebrospinal fluid of schizophrenic patients

Concentrations of norepinephrine and metabolites of biogenic amines were measured in lumbar cerebrospinal fluid of 30 patients with chronic schizophrenia, nine of whom were polyuric. The mean level of norepinephrine was two-fold higher (p < or = 0.025) in polyuric patients than in patients whose excretion of urine was within the normal range. CSF levels of histamine's primary metabolite, tele-methylhistamine, an index of brain histaminergic activity, were positively correlated (p < 0.005) with daily urine volume. These results are consistent with the known influence of norepinephrine and histamine on fluid regulation and suggest that norepinephrine and histamine may be involved in psychogenic polydipsia-polyuria in schizophrenic patients.

Bone formation in hydroxyapatite orbital implants

PURPOSE

We examined the histopathologic features of two hydroxyapatite orbital implants that were removed from two patients.

METHODS

Two surgically removed hydroxyapatite orbital implants were decalcified and processed for routine light microscopic examination.

RESULTS

Both implants demonstrated fibrovascular ingrowth and foci of bone formation.

CONCLUSION

Bone may form in hydroxyapatite orbital implants.

Nasopharyngeal carcinoma. A study examining Asian patients treated in the United States

From 1972 to 1991, 126 Asian patients with nasopharyngeal carcinoma underwent definitive radiation therapy for locoregional disease: 86 men, 40 women. Median age was 50. All patients received external-beam irradiation with cobalt 60 or 4-18 MV x-rays. Local recurrence, regional recurrence, and distant metastases were 22%, 11%, and 23%, respectively. Local recurrence progressively increased with increasing T stage, but doses in those who recurred did not differ from the group as a whole. Regional recurrence was not associated with T or N stage or dose. Patients with N2 disease had the highest distant metastatic rate. The 5- and 10-year overall survival rates were 54% and 38%, respectively. Of age, gender, and histology, only age less than 50 was found to be favorably prognostic. No severe long-term complications were observed, and acute reactions were acceptable. Our survival results are comparable with results found both in Asia and North America. Nonetheless, altered fractionation techniques and/or other radiation modalities should be further explored to improve locoregional control.

Release of glutamate from striatum of freely moving rats by pros-methylimidazoleacetic acid

The effect of pros-methylimidazoleacetic acid (p-MIAA) was measured on the release of glutamate and aspartate from cerebral cortex, hippocampus, and striatum of freely moving rats, and on the uptake of 14C by striatal slices incubated in the presence of L-[14C]-glutamate. Twenty-four hours after implantation of a dialysis fiber, striatum, hippocampus, or cerebral cortex spontaneously released both glutamate and aspartate in the micromolar range. p-MIAA (1 microM to 1 mM), added to the dialysis perfusate, elicited a concentration-dependent increase of glutamate release from striatum with a maximal increase of about threefold. This effect did not occur in hippocampus or cortex. In none of these regions did p-MIAA increase aspartate release significantly. The p-MIAA effect was not mimicked by its isomer tele-methyl-imidazoleacetic acid. p-MIAA did not influence the uptake of glutamate by striatal slices. The glutamate-releasing action of p-MIAA may affect striatal function and explain the positive correlation between levels of p-MIAA in CSF and the severity of Parkinson's disease.

Histamine metabolites in cerebrospinal fluid of patients with chronic schizophrenia: their relationships to levels of other aminergic transmitters and ratings of symptoms

Levels of the histamine metabolites, tele-methylhistamine (t-MH) and tele-methylimidazoleacetic acid (t-MIAA), and metabolites of other aminergic transmitters and of norepinephrine were measured in cerebrospinal fluid of 36 inpatients with chronic schizophrenia and eight controls. The mean t-MH level from controls was nearly identical to the levels seen previously in healthy volunteers. Compared with controls, the mean level of t-MH in the schizophrenic patients was 2.6-fold higher (p = 0.006); 21 of the patients had levels exceeding the range of controls. There was no significant difference (p > 0.05) in levels of other analytes, although the levels of t-MH correlated significantly with those of t-MIAA, homovanillic acid, 3,4-dihydroxyphenylacetic acid, norepinephrine, 3-methoxy-4-hydroxyphenylglycol and 5-hydroxyindoleacetic acid. The difference in levels of t-MH were not attributable to medication, since those taking (n = 10) or withdrawn from (n = 26) neuroleptic drugs had nearly the same mean levels of t-MH; each group had higher levels than controls (ANOVA: p < 0.05). Patients with or without tardive dyskinesia showed no significant differences in means of any analyte. Only levels of t-MH among those with schizophrenia correlated with positive symptom scores on the Psychiatric Symptom Assessment Scale (rs = 0.45, p < 0.02). The elevated levels of t-MH in cerebrospinal fluid, which represent histamine that was released and metabolized, suggest increased central histaminergic activity in patients with chronic schizophrenia.

Reasoning abilities in Psy.D. and Ph.D. clinical graduate students: a preliminary study

Clinical students in regionally representative Psy.D. and Ph.D. programs responded to a questionnaire that assessed everyday reasoning and psychological knowledge. Ph.D.s scored higher on the Methodology Reasoning test and the Conditional Probability test, while there were no differences on the Verbal or Statistical Reasoning tests or the Psychology questions. Calibration curves indicated that Psy.D.s tended to be somewhat more overconfident in their responses than Ph.D.s. Similarities and differences between the performance of the Psy.D.s and Ph.D.s are discussed, as well as the limitations and implications of the study.

Measurement of histamine metabolites in brain and cerebrospinal fluid provides insights into histaminergic activity

Measurements of the concentrations of histamine's metabolites, tele-methylhistamine (t-MH) and tele-methylimidazoleacetic acid (t-MIAA), in brain have been used to evaluate histamine turnover in brains of animals, and the same measurements in CSF have been used to infer histaminergic activity in brains of man. In regions of rat brain, half-lives of histamine are shorter than those of dopamine, 5-hydroxytryptamine and norepinephrine. Studies of human CSF suggest that brain histaminergic activity increases with age and is higher in females than in males.

Clinical and research attitudes of Psy.D. and Ph.D. clinical graduate students

A survey of 137 Psy.D. and Ph.D. clinical graduate students out of 561 at 4 Ph.D. schools and 4 Psy.D. schools indicated that these Ph.D. students found knowledge of statistics and research design to be more useful than the 98 Psy.D. students. A need to replicate and to ascertain the basis for such differences was discussed.

Physicians practicing other occupations, especially literature

Literature has been the favored nonmedical pursuit of physicians probably because the practice of medicine is suffused with narratives, the patient's history being one. Arthur Conan Doyle regarded medicine as a "grim romance," Somerset Maugham as an opportunity to see "life in the raw," and William Carlos Williams treated "the patient as a work of art." These sentiments may be linked to humanistic medicine. At some medical schools, literature is taught in the context of and integrated with medicine in an attempt to enhance ethics and empathy which were explicitly expressed by some physician-writers.

Paralysis of downgaze in two patients with clinical-radiologic correlation

Selective downgaze paralysis was correlated with discrete bilateral lesions at the mesencephalic-diencephalic junction in a 9-year-old girl following severe pneumococcal meningitis, and in a 64-year-old man who suffered an embolic infarction. Magnetic resonance imaging demonstrated bilateral lesions in the region of the rostral interstitial nucleus of the medial longitudinal fasciculus. Clinical-radiologic correlation allowed identification of the likely vascular cause in both patients.

Pseudomemory in hypnotized and task-motivated subjects

Highly hypnotizable hypnotized (H; n = 16) and task-motivated (TM; n = 13) subjects received pseudomemory suggestions (see Orne, 1979). TM subjects reported being more awake and motivated than did H subjects and were more likely to pass the target noise suggestion. However, 69% of subjects in both conditions who passed the noise suggestion reported pseudomemories. Pseudomemory rate (for H subjects, 69% and for TM subjects, 46%) was not reduced by informing subjects that they could distinguish reality and fantasy in a state of deep concentration. At final inquiry, after deep concentration, pseudomemories remained stable (for H subjects, 75% and for TM subjects, 54%). As predicted, H subjects reported more unsuggested noises and more pseudomemories of novel noises than did TM subjects. Subjects who reported pseudomemories were more confident in the accuracy of their memories than were subjects who reported that the suggested noises were imagined.

Finding the hypnotic virtuoso--another look: a brief communication

Student volunteers who scored 9 (N = 20), 10 (N = 19), 11 (N = 26), and 12 (N = 15) on a live-administered Harvard Group Scale of Hypnotic Susceptibility (HGSHS:A) of Shor and E. Orne (1962) were retested with the individually administered Stanford Hypnotic Susceptibility Scale (SHSS:C) of Weitzenhoffer and Hilgard (1962). There appeared to be a break in HGSHS:A's predictive ability at 11 suggestions passed. Whereas a majority of Ss who passed at least 11 HGSHS:A suggestions retested in SHSS:C "virtuoso" range (i.e., passed at least 11 suggestions), a relatively small percentage of Ss who passed fewer than 11 HGSHS:A suggestions retested as SHSS:C virtuosos. These results are generally consistent with previous research (Register & Kihlstrom, 1986) using a standard taped-recorded HGSHS:A induction.

Pseudomemory in hypnotized and task-motivated subjects

Highly hypnotizable hypnotized (H; n = 16) and task-motivated (TM; n = 13) subjects received pseudomemory suggestions (see Orne, 1979). TM subjects reported being more awake and motivated than did H subjects and were more likely to pass the target noise suggestion. However, 69% of subjects in both conditions who passed the noise suggestion reported pseudomemories. Pseudomemory rate (for H subjects, 69% and for TM subjects, 46%) was not reduced by informing subjects that they could distinguish reality and fantasy in a state of deep concentration. At final inquiry, after deep concentration, pseudomemories remained stable (for H subjects, 75% and for TM subjects, 54%). As predicted, H subjects reported more unsuggested noises and more pseudomemories of novel noises than did TM subjects. Subjects who reported pseudomemories were more confident in the accuracy of their memories than were subjects who reported that the suggested noises were imagined.

Decreasing junk-food consumption through the use of self-management procedures: a case study

By using a self-management program, a 25-yr.-old white male was able to decrease the amount of junk food and beverage consumed while increasing the amount of healthier food and beverage ingested during evening snacks. This change was evident at 6 wk. and at a 6-mo. follow-up. Factors contributing to this success were discussed.

Levels of pros-methylimidazoleacetic acid: correlation with severity of Parkinson's disease in CSF of patients and with the depletion of striatal dopamine and its metabolites in MPTP-treated mice

The cerebrospinal fluid (CSF) levels of pros-methylimidazoleacetic acid (p-MIAA) in thirteen medication-free patients with mild to moderate Parkinson's disease were highly correlated (Spearman's rho = 0.749, p less than 0.005) with the severity of signs of the disease as scored on the Columbia University Rating Scale. Levels of p-MIAA in males (n = 8) and females (n = 5) were each significantly correlated with scores of severity (rho = 0.78, p less than 0.05 and rho = 1.0, p less than 0.05, respectively). In C57BL/6 mice treated with 1-methyl-4-phenyl-1,2,3,6-tetra-hydropyridine (MPTP), levels of p-MIAA were significantly correlated with the depleted levels of dopamine (r = 0.85, p less than 0.01), homovanillic acid (r = 0.79, p less than 0.02), 3,4-dihydroxyphenylacetic acid (r = 0.84, p less than 0.01) and norepinephrine (r = 0.91, p less than 0.002) in striatum, but not in cortex of the same mice. No such correlations were observed in either striatum or cortex of saline-treated control mice. Mean levels of p-MIAA in CSF did not differ significantly between patients and age-matched controls; and mean levels of p-MIAA in striatum did not differ between MPTP-treated mice and controls. The simplest hypothesis to account for these strong correlations in the absence of differences in mean levels of p-MIAA is that accumulation of p-MIAA [or process(es) that govern its accumulation] influences a failing nigrostriatal system. It is also possible (in analogy with findings in other diseases and with other drugs) that measurements of the putative metabolite(s) of p-MIAA may distinguish the patients and the MPTP-treated mice from their respective controls. Elucidation of the processes that regulate formation and disposition of p-MIAA in brain and information on the neural effects of p-MIAA, its precursors and its putative metabolites may yield insight into factors that regulate the progression of Parkinson's disease, and may shed additional light on the cause(s) of this disease.

Influence of age and gender on the levels of histamine metabolites and pros-methylimidazoleacetic acid in human cerebrospinal fluid

The metabolites of histamine, tele-methylhistamine (t-MH) and tele-methylimidazoleacetic acid (t-MIAA), were measured in cerebrospinal fluid (CSF) from 47 subjects with neurological disorders and healthy controls. In lumbar CSF, concentrations of these metabolites were significantly correlated. Levels of t-MH, t-MIAA and their sum (which represents virtually all histamine metabolized in brain) were significantly higher in CSF from older subjects and were positively correlated with age. Females had higher levels of histamine metabolites than males. Males had higher levels of pros-methylimidazoleacetic acid (p-MIAA), an isomer of t-MIAA that is not a metabolite of histamine. Levels of p-MIAA increased with age among men. Analysis of covariance indicated that the subjects' health status had little or no effect on age- or sex-related differences in levels of analytes in CSF; sex-related differences were independent of changes attributed to age. These results are in contrast to those of age-related effects on levels of other aminergic transmitter metabolites in CSF and suggest that metabolic activity of histamine in brain may increase with age.

Serotonergic modulation of the release of endogenous norepinephrine from rat hypothalamic slices

Ca+(+)-dependent release of endogenous norepinephrine (NE) and dopamine from superfused rat hypothalamic slices was stimulated by 40 mM K+. 20 mM K+ released only NE. Two consecutive exposures to 20 mM K+ (S1 and S2, respectively) produced NE release of similar magnitude (S2/S1 = 1.03 +/- 0.08). Serotonin (5-HT), 3 to 10 microM, in the presence of methylsergide or ritanserin (antagonists at 5-HT1-like and 5-HT2 receptors), caused a concentration-dependent decrease of K(+)-evoked NE release. 5-HT alone did not alter K(+)-evoked NE release. 2-Methyl-serotonin, 2-methyl-5-hydroxytryptamine, 3 to 10 microM (a selective 5-HT3 agonist), mimicked the 5-HT response in the presence and in the absence of ritanserin. A highly selective 5-HT3 antagonist, (3 alpha-tropanyl)1H-indole-3-carboxylic acid ester (ICS 205-930), 1 nM, inhibited the effect of both agonists. The isomers of another highly selective 5-HT3 antagonist, zacopride, inhibited the effect of 2-methyl-serotonin, 2-methyl-5-hydroxytryptamine, at a concentration range, 0.03 to 20 nM, characteristic of their interaction with 5-HT3 receptors. alpha-Methyl-serotonin, alpha-methyl-5-hydroxytryptamine, a selective 5-HT1-like/5-HT2 agonist, failed to affect the K(+)-evoked NE release, but antagonized the effect of 2-methyl-serotonin, 2-methyl-5-hydroxytryptamine. These observations provide direct evidence that, in rat hypothalamus, 5-HT modulates release of endogenous NE through activation of 5-HT3 and, possibly, 5-HT1C receptors.

Histamine metabolites and pros-methylimidazoleacetic acid in human cerebrospinal fluid

In cerebrospinal fluid, levels of the histamine metabolites, tele-methylhistamine and tele-methylimidazole-acetic acid, were higher in elderly than in young people, and women had higher levels than men. Therefore, age and gender should be considered in studies of histamine metabolites as exemplified by their measurements in cerebrospinal fluid of patients with Huntington's disease. Levels of pros-methylimidazoleacetic acid, an isomer of tele-methylimidazoleacetic acid and not a metabolite of histamine, were higher in cerebrospinal fluid of men than of women. Levels of pros-methylimidazoleacetic acid in cerebrospinal fluid were highly positively correlated with the severity of Parkinson's disease in a group of non-medicated, mildly to moderately affected patients.

Literalism and hypnosis: hypnotic versus task-motivated subjects

To extend previous literalism research with hypnotized and simulating subjects, we compared literalism rates of hypnotized, highly hypnotizable subjects (N = 12) with nonhypnotized, task-motivated subjects (N = 12) who were also highly hypnotizable. Six questions of the type used by Erickson (e.g., "Do you mind telling me your name?") constituted tests of literalism (scored if response is "Yes" or "No," either verbally or nonverbally). Whereas Erickson claimed that 97% of his "deep trance" subjects and 90% of his "medium trance" subjects exhibited literal responses, we found that 87.5% of hypnotized, high-hypnotizable subjects' responses were nonliteral. Hypnotized and task-motivated subjects did not differ in their literal responding to the individual questions or when their scores were summed across questions. No support was secured for Erickson's assertion that literalism is a cardinal feature of hypnosis.

Influence of age and gender on the levels of histamine metabolites and pros-methylimidazoleacetic acid in human cerebrospinal fluid

The metabolites of histamine, tele-methylhistamine (t-MH) and tele-methylimidazoleacetic acid (t-MIAA), were measured in cerebrospinal fluid (CSF) from 47 subjects with neurological disorders and healthy controls. In lumbar CSF, concentrations of these metabolites were significantly correlated. Levels of t-MH, t-MIAA and their sum (which represents virtually all histamine metabolized in brain) were significantly higher in CSF from older subjects and were positively correlated with age. Females had higher levels of histamine metabolites than males. Males had higher levels of pros-methylimidazoleacetic acid (p-MIAA), an isomer of t-MIAA that is not a metabolite of histamine. Levels of p-MIAA increased with age among men. These results are in contrast to those of age-related effects on levels of other aminergic transmitter metabolites in CSF and suggest that metabolic activity of histamine in brain may increase with age.

Literalism as a marker of hypnotic "trance": disconfirming evidence

The responses given by highly hypnotizable, hypnotic subjects and those of unhypnotizable subjects who simulated hypnosis to questions of the type, "Do you mind telling me your name?" and "Do you mind standing up?" were contrasted. The purpose was to examine Erickson's (1980) assertion that literalism (answering "yes" or "no" verbally or nonverbally without any cognitive elaboration) is a marker of hypnotic "trance." Simulators exhibited a greater rate of literalism than hypnotic "virtuosos" (i.e., extreme scorers on both group and individual hypnotizability measures). Hypnotized subjects and nonhypnotized subjects approached in the campus library responded comparably. Because less than a third of hypnotic virtuosos responded literally, our results strongly refuted Erickson's assertion that literalism is a cognitive feature of hypnosis.

Pharmacological receptors: the need for a compendium of classification, nomenclature and structure

In an attempt to contain the chaos of receptor nomenclature, the supplement distributed with this issue of TiPS catalogues cell surface receptors and their subtypes according to the most commonly used nomenclature and describes them in pharmacological, biochemical and molecular terms. This reporting of the status quo will be an invaluable aid to communication, but all scientists (not just pharmacologists) working on receptors would agree that a radical and rational classification of receptors also needs to be initiated. In this article, Jack Peter Green proposes a system of (and mechanism for) classification that should satisfy both the 'taxonomic realists' and the 'taxonomic skeptics'.

Literalism as a marker of hypnotic "trance": Disconfirming evidence

The responses given by highly hypnotizable, hypnotic subjects and those of unhypnotizable subjects who simulated hypnosis to questions of the type, "Do you mind telling me your name?" and "Do you mind standing up?" were contrasted. The purpose was to examine Erickson's (1980) assertion that literalism (answering "yes" or "no" verbally or nonverbally without any cognitive elaboration) is a marker of hypnotic "trance." Simulators exhibited a greater rate of literalism than hypnotic "virtuosos" (i.e., extreme scorers on both group and individual hypnotizability measures). Hypnotized subjects and nonhypnotized subjects approached in the campus library responded comparably. Because less than a third of hypnotic virtuosos responded literally, our results strongly refuted Erickson's assertion that literalism is a cognitive feature of hypnosis.