Rest-activity rhythm disruption and metabolic health in schizophrenia: a cross-sectional actigraphy study of community-dwelling people living with schizophrenia and non-psychiatric comparison participants

STUDY OBJECTIVES

People living with schizophrenia (PLWS) have increased physical comorbidities and premature mortality which may be linked to dysregulated rest-activity rhythms (RARs). This study aimed to compare RARs between PLWS and non-psychiatric comparison participants (NCs); examine the relationships of RARs with age, sleep, metabolic and physical health outcomes; and, among PLWS, relationships of RARs with illness-related factors.

METHODS

The study sample included 26 PLWS and 36 NCs, assessed with wrist-worn actigraphy to compute RAR variables and general sleep variables. Participants completed assessments for clinical symptoms, physical health, sleep quality, medication use, and assays for fasting glycosylated hemoglobin (HbA1c) levels. We examined group differences in RAR and sleep variables, relationships of RAR variables with metabolic and physical health measures, and, among PLWS, relationships between RAR variables and illness-related measures.

RESULTS

PLWS had significantly shorter active periods, lower relative amplitude, and lower mean activity during their most active 10 hours compared to the NCs (Cohen's d=.79, .58, and .62; respectively). PLWS had poorer sleep quality, greater mean percent sleep, less wake after sleep onset, and higher total sleep time (TST) variability compared to NCs. PLWS had higher rates of antidepressant, anxiolytic, and antipsychotic medication use compared to NCs, which may have impacted sleep quality and objective sleep measures. Across both groups, more fragmented and variable RARs were associated with higher HbA1c levels (ηp2=0.10) and worse physical health (ηp2=0.21). Among PLWS, RARs were correlated with TST (rs=.789, p<0.01) and percent sleep (rs=.509, p<0.05), but not with age, sleep quality, or other illness-related factors.

CONCLUSIONS

RARs provide unique information about sleep and activity for PLWS and have the potential for targeted interventions to improve metabolic health and mortality.

Self-compassion, but not compassion toward others, is associated with better physical health: A cross-sectional study

Compassion is a modifiable construct that is associated with better physical health outcomes but, to our knowledge, has seldom been studied in people with schizophrenia (PwS) despite its applicability to counteract widespread depression in this community that might prevent positive health behaviors. We hypothesized that, compared to non-psychiatric comparison subjects (NCs), PwS would have lower compassion toward self (CTS), lower compassion toward others (CTO), and a positive association between compassion and health outcomes, such as physical wellbeing, comorbidities, and plasma hs-CRP. This cross-sectional study examined differences in physical health, CTS, and CTO in 189 PwS and 166 NCs. We used general linear models to analyze the relationship between compassion and health. As hypothesized, PwS had lower levels of CTS and CTO, worse physical well-being, more comorbidities, and higher levels of plasma hs-CRP than NCs. In the combined sample, higher CTS was significantly associated with better physical well-being and fewer comorbidities, while higher CTO was significantly associated with more comorbidities. In PwS alone, higher CTS was significantly associated with better physical well-being and lower levels of hs-CRP. CTS seemed to have a larger positive association with physical health than CTO, with depression acting as a potential mediator for CTS. Exploring effects of CTS interventions on physical health and health behaviors could be a promising next step.

Astroglial toxicity promotes synaptic degeneration in the thalamocortical circuit in frontotemporal dementia with GRN mutations

Mutations in the human progranulin (GRN) gene are a leading cause of frontotemporal lobar degeneration (FTLD). While previous studies implicate aberrant microglial activation as a disease-driving factor in neurodegeneration in the thalamocortical circuit in Grn-/- mice, the exact mechanism for neurodegeneration in FTLD-GRN remains unclear. By performing comparative single-cell transcriptomics in the thalamus and frontal cortex of Grn-/- mice and patients with FTLD-GRN, we have uncovered a highly conserved astroglial pathology characterized by upregulation of gap junction protein GJA1, water channel AQP4, and lipid-binding protein APOE, and downregulation of glutamate transporter SLC1A2 that promoted profound synaptic degeneration across the two species. This astroglial toxicity could be recapitulated in mouse astrocyte-neuron cocultures and by transplanting induced pluripotent stem cell-derived astrocytes to cortical organoids, where progranulin-deficient astrocytes promoted synaptic degeneration, neuronal stress, and TDP-43 proteinopathy. Together, these results reveal a previously unappreciated astroglial pathology as a potential key mechanism in neurodegeneration in FTLD-GRN.

Granulin loss of function in human mature brain organoids implicates astrocytes in TDP-43 pathology

Loss of function (LoF) of TAR-DNA binding protein 43 (TDP-43) and mis-localization, together with TDP-43-positive and hyperphosphorylated inclusions, are found in post-mortem tissue of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) patients, including those carrying LoF variants in the progranulin gene (GRN). Modeling TDP-43 pathology has been challenging in vivo and in vitro. We present a three-dimensional induced pluripotent stem cell (iPSC)-derived paradigm-mature brain organoids (mbOrg)-composed of cortical-like-astrocytes (iA) and neurons. When devoid of GRN, mbOrgs spontaneously recapitulate TDP-43 mis-localization, hyperphosphorylation, and LoF phenotypes. Mixing and matching genotypes in mbOrgs showed that GRN-/- iA are drivers for TDP-43 pathology. Finally, we rescued TDP-43 LoF by adding exogenous progranulin, demonstrating a link between TDP-43 LoF and progranulin expression. In conclusion, we present an iPSC-derived platform that shows striking features of human TDP-43 proteinopathy and provides a tool for the mechanistic modeling of TDP-43 pathology and patient-tailored therapeutic screening for FTD and ALS.

Plastin 3 rescues BDNF-TrkB signaling in spinal muscular atrophy

In this issue, Hennlein and colleagues (2023. J. Cell Biol.https://doi.org/10.1083/jcb.202204113) show that F-actin-bundling protein Plastin 3 is drastically reduced in motor neurons with spinal muscular atrophy, whereas virus-mediated overexpression of Plastin 3 restores actin cytoskeleton and promotes BDNF-TrkB signaling in the growth cones of spinal motor neurons.

Confidence interval prediction for neural network models

To derive an estimate of a neural network's accuracy as an empirical modeling tool, a method to quantify the confidence intervals of a neural network model of a physical system is desired. In general, a model of a physical system has error associated with its predictions due to the dependence of the physical system's output on uncontrollable or unobservable quantities. A confidence interval can be computed for a neural network model with the assumption of normally distributed error for the neural network. The proposed method accounts for the accuracy of the data with which the neural network model is trained.

Decoding the ancient Greek astronomical calculator known as the Antikythera Mechanism

The Antikythera Mechanism is a unique Greek geared device, constructed around the end of the second century bc. It is known that it calculated and displayed celestial information, particularly cycles such as the phases of the moon and a luni-solar calendar. Calendars were important to ancient societies for timing agricultural activity and fixing religious festivals. Eclipses and planetary motions were often interpreted as omens, while the calm regularity of the astronomical cycles must have been philosophically attractive in an uncertain and violent world. Named after its place of discovery in 1901 in a Roman shipwreck, the Antikythera Mechanism is technically more complex than any known device for at least a millennium afterwards. Its specific functions have remained controversial because its gears and the inscriptions upon its faces are only fragmentary. Here we report surface imaging and high-resolution X-ray tomography of the surviving fragments, enabling us to reconstruct the gear function and double the number of deciphered inscriptions. The mechanism predicted lunar and solar eclipses on the basis of Babylonian arithmetic-progression cycles. The inscriptions support suggestions of mechanical display of planetary positions, now lost. In the second century bc, Hipparchos developed a theory to explain the irregularities of the Moon's motion across the sky caused by its elliptic orbit. We find a mechanical realization of this theory in the gearing of the mechanism, revealing an unexpected degree of technical sophistication for the period.

Booster seat use and reasons for nonuse

BACKGROUND

Many children 4 to 9 years old are inappropriately restrained in vehicles and are at risk for injury in crashes.

OBJECTIVES

This study was undertaken to determine the rate of booster seat use and the reasons for nonuse.

METHODS

Observations were conducted at a random sample of day care centers, and drivers of unrestrained children 4 to 8 years old were interviewed to determine the reasons for lack of booster seat use.

RESULTS

Observations were conducted on 149 children. Shoulder belt use significantly increased with the age of the child; 28.3% of 4-year-olds and 70.0% of 6- to 8-year-olds used lap-shoulder belts. Overall, 27.7% of children in the target age group used booster seats; only 10% of children 6 to 8 years old were restrained with booster seats. Booster seat use decreased when there were 3 or more passengers in the vehicle. The most common reason for lack of booster seat use was that parents thought the child was large enough to use the regular lap-shoulder belt system, or problems with attempting to use the seat in the vehicle. More than one half of parents who were not using booster seats at the time of the survey reported owning seats.

CONCLUSION

This study indicates that parental misconceptions about size and safety of regular restraint equipment are the most common reason that children are not appropriately restrained in vehicles. This information can be used to guide community intervention programs.

Managing the care of complex, difficult patients in the medical-surgical setting

The increasing medical, psychological, and social complexity of hospitalized patients is a serious concern. Most staff nurses are inadequately prepared to deal with the complexity of these patient's issues. The difficult patient is described as having a medical condition requiring hospitalization and who also exhibits problems such as pain, substance abuse, and issues such as anger, manipulation, or noncompliance which are difficult and challenging behaviors. An overview of the most troublesome patients seen in the inpatient setting today and some clinical direction on how to best manage these patients are presented.

Self-reported narcissism and perceived parental permissiveness and authoritarianism

The hypothesis that inadequate parenting promotes the development of pathological narcissism was tested in a sample of 370 undergraduate students. They responded to the O'Brien (1987) Multiphasic Narcissism Inventory (OMNI) and to measures of parental permissiveness, authoritarianism, and authoritativeness. Perceived parental permissiveness and authoritarianism served as independent predictors of greater narcissistic tendencies. The students who scored high on the OMNI were also less likely to evaluate both of their parents as having been especially strong in their use of the adjustment-promoting authoritative style. Theoretical efforts to link narcissism with inadequate parenting therefore may have merit and may deserve additional research attention.

Further contrasts between self-reflectiveness and internal state awareness factors of private self-consciousness

Although widely used as a unitary measure of self-focused attention, the Private Self-Consciousness subscale (Fenigstein, Scheier, & Buss, 1975) contains two factors. In the present study, this subscale and its self-reflectiveness (SR) factor predicted greater shame, guilt, other-directedness, and social anxiety; but the internal state awareness (ISA) factor displayed relationships that were in the opposite direction. Contrasts between SR and ISA often became more obvious in partial correlations, when one factor was examined while controlling for the other. In relationships with personal and social identity, SR appeared to reflect public as much as private self-consciousness. These data support recent suggestions that it may be necessary to construct more adequate measures of private self-consciousness.

Characterisation of the copper uptake mechanism and isolation of the ceruloplasmin receptor/copper transporter in human placental vesicles

In this paper we have studied copper (Cu) uptake by microvillar vesicles isolated from human term placenta. We have characterised Cu uptake from CuHis2 complexes and shown that ceruloplasmin (Cp) inhibits uptake. Inhibition is complex and variable; in one series of experiments, the Vmax for uptake drops from 31.3 +/- 1.2 nmol/min per mg vesicle protein without added Cp to 11.3 +/- 1 nmol/min per mg vesicle protein at 91 micrograms/ml Cp. Similarly, the K0.5 increases from 0.35 +/- 0.08 microM to 1.35 +/- 0.25 microM, while the n value (the Hill coefficient) falls from 1.9 +/- 0.23 in the absence of Cp to 1.1 +/- 0.13 In another series, Cp had no effect below concentrations of about 100 micrograms/ml and in a third series only increased K0.5. The variability in effect seems to be related to the specific activity of the ceruloplasmin, which in turn is related to the copper complexes of the protein. The effect is specific for Cp; apotransferrin and a2-macroglobulin have no effect. 67Cu-labelled ceruloplasmin binds specifically to vesicles of term placenta with an affinity of 2.8 microU/mg vesicle protein and a Bmax of 79 microU/mg vesicle protein. CuHis2, but not histidine alone, can block the uptake. The data can be reconciled by proposing that the binding site of the transporter is relatively small and recognises a Cu-dihistidine structure common to the low-molecular-weight complex and to the Type I and Type II coppers of ceruloplasmin. We have used these observations to develop an isolation method for the transporter and have identified it as a protein of M(r) 90,000 which is closely associated with alkaline phosphatase. There are also two proteins of M(r) 45,000 and 40,000 which may be breakdown products of the larger complex. Antibodies to the 45,000 protein block Cu binding and uptake from CuHis2 complexes, strongly implicating it as the copper transporter/ceruloplasmin receptor of human term placenta.

Chemical reactivity of some isothiazolone biocides

Chemical reactions between the isothiazolone biocides, N-methylisothiazol-3-one (MIT), benzisothiazol-3-one (BIT) and 5-chloro-N-methylisothiazol-3-one (CMIT) with cysteine have been investigated by u.v. and NMR spectroscopy. At physiological pH all three agents interacted oxidatively with thiols to form disulphides. Further interaction with thiols caused the release of cystine and formation of a reduced, ring-opened form of the biocide (mercaptoacrylamide). In an analogous fashion to the initial reaction the mercaptoacrylamide reacted with another molecule of biocide to give biocide dimers. NMR spectral studies indicated that for CMIT the mercaptoacrylamide form is capable of tautomerization to a highly reactive thio-acyl chloride. Formation of mercaptoacrylamide was in all cases highly pH-dependent. Alcohol dehydrogenase was insensitive to all three agents but was highly sensitive to CMIT when co-administered with dithiothreitol. Capacity to form a thioacyl chloride from the mercaptoacrylamide is suggested to account for much of this enhanced activity. Stopped-flow spectroscopic studies showed rates of reaction with glutathione (GSH) to directly parallel antimicrobial activity. Additionally, CMIT was able to react directly with both ionization states of GSH (pH 7-10) whilst BIT and MIT appeared only to interact when the glutamyl-nitrogen of GSH was charged (pH 8.5).

Rearrangement of the T-cell-receptor beta-chain gene in the diagnosis of lymphoproliferative disorders

The arrangement of the T-cell-receptor and immunoglobulin genes has been analysed in 77 cases of lymphoproliferative disorder. All 6 T-cell leukaemias and 16 of 19 T-cell lymphomas showed rearrangement of the gene coding for the beta chain of the T-cell receptor, associated in all cases with a germline arrangement of the immunoglobulin genes. All 36 B-cell leukaemias and all 16 B-cell lymphomas showed rearrangement of immunoglobulin genes; the T-cell-receptor gene was in the germline configuration in most of these cases but showed a rearranged pattern in 3 cases (2 chronic lymphatic leukaemias and 1 immunoblastic lymphoma). The combined use of T-cell-receptor and immunoglobulin gene probes promises to be a valuable means of identifying and classifying T-cell neoplasms.

Insulin tolerance test: human growth hormone response and insulin resistance in primary unipolar depressed, bipolar depressed and control subjects

Preliminary data from the National Institute of Mental Health-Clinical Research Branch Collaborative Program on the Psychobiology of Depression dealing with the human growth hormone (hGH) response to the Insulin Tolerance Test (ITT) during the pre-treatment (drug-free) period of the study are presented in this paper. Data are reported for 54 unipolar depressed, 21 bipolar depressed, and 40 normal control subjects, who represent approximately 50% of the final subject sample to be studied. In this population the unipolar depressed subjects showed a significantly greater resistance to insulin-induced hypoglycaemia than bipolar and control subjects. After applying the inclusion/exclusion criteria necessary to interpret hGH responses accurately, the data from only 54 subjects were acceptable. Mean peak hGH concentrations were not significantly different among the three groups. There was, however, a significant difference in the distributions of the hGH peak response, with the bipolar depressed population demonstrating greater variability in response than unipolar and control populations. These findings are discussed as they relate to previous reports and theoretical considerations.

The biological fate of sulphur colloid

The in-vivo behaviour of sulphur colloid has been investigated using colloids labelled with 35S as well as 99m Tc. The rates of clearance of 35S and 99m Tc from the blood, the rates of accumulation in liver and bone and the distribution of the two radioisotopes in various organs are all markedly different. The results demonstrate that although technetium is rapidly removed from the blood stream and primarily accumulated in the liver the colloid particles themselves are broken down in vivo with the release of sulphur.

The physical and chemical characteristics of sulphur colloids

The characteristics of sulphur colloids have been investigated using colloids labelled with 35S as well as with 99mTc. The results support a model in which technetium is incorporated in the body of the particle rather than on its surface. Elemental sulphur on the surface of the particle is susceptible to attack both by sulphide ions and by protein and other materials containing --SH groups. The ready conversion of sulphur to soluble polysulphides means that sulphur colloid particles undergo conspicuous changes in diameter, both while standing in a closed vial, and on injection into body fluids. This behaviour casts doubts on the value of routine particle-size measurement as a quality control procedure.