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Aim: \ud Cardiac arrest (CA) survival has diverse psychosocial outcomes for both survivors and their close family, with little known regarding long-term adjustment and recovery experiences. We explored the psychological adjustment and experiential perspectives of survivors and families in the second year after out-of-hospital cardiac arrest (OHCA).\ud \ud Methods:\ud A prospective, mixed-methods study of adult OHCA survivors in Victoria, Australia was conducted. Eighteen survivors and 12 family members completed semi-structured interviews 14–19 months post-arrest. Survivors’ cognition, anxiety, depression and post-traumatic stress symptoms were measured using a battery of psychological assessments. A thematic content analysis approach was applied to qualitative interview data by two independent investigators, with data coded and categorised into themes and sub-themes.\ud \ud Results:\ud Survivors’ cognition, depression, anxiety and post-traumatic stress symptoms were not clinically elevated in the second year post-arrest. Subjective cognitive failures were associated with increased anxiety but not with mental state. Depression was significantly correlated with post-traumatic symptoms. Six primary themes emerged from survivors’ recovery stories, focused on: awakening and realisation, barriers to adjustment, psychosocial difficulties, integration, protective factors and unmet needs. Family perspectives revealed four primary themes focused on trauma exposure, survivor adjustment problems, family impact, and areas for service improvement.\ud \ud Conclusion:\ud Survivors and their family members describe complex recovery journeys characterised by a range of psychosocial adjustment challenges, which are not adequately captured by common psychological measures. Post-arrest care systems are perceived by survivors and their families as inadequate due to a lack of accurate information regarding post-arrest sequalae, limited follow-up and inconsistent access to allied health care.

The typical vertebrate centromeres contain long stretches of highly repeated DNA sequences (satellite DNA). We previously demonstrated that the karyotypes of the species belonging to the genus Equus are characterized by the presence of satellite-free and satellite-based centromeres and represent a unique biological model for the study of centromere organization and behavior. Using horse primary fibroblasts cultured in vitro, we compared the segregation fidelity of chromosome 11, whose centromere is satellite-free, with that of chromosome 13, which has similar size and a centromere containing long stretches of satellite DNA. The mitotic stability of the two chromosomes was compared under normal conditions and under mitotic stress induced by the spindle inhibitor, nocodazole. Two independent molecular-cytogenetic approaches were used—the interphase aneuploidy analysis and the cytokinesis-block micronucleus assay. Both assays were coupled to fluorescence in situ hybridization with chromosome specific probes in order to identify chromosome 11 and chromosome 13, respectively. In addition, we tested if the lack of centromeric satellite DNA affected chromatid cohesion under normal and stress conditions. We demonstrated that, in our system, the segregation fidelity of a chromosome is not influenced by the presence of long stretches of tandem repeats at its centromere. To our knowledge, the present study is the first analysis of the mitotic behavior of a natural satellite-free centromere.

Summary A common assumption is that human chromosomes carry equal chances of mis-segregation during compromised cell division. Human chromosomes vary in multiple parameters that might generate bias, but technological limitations have precluded a comprehensive analysis of chromosome-specific aneuploidy. Here, by imaging specific centromeres coupled with high-throughput single-cell analysis as well as single-cell sequencing, we show that aneuploidy occurs non-randomly following common treatments to elevate chromosome mis-segregation. Temporary spindle disruption leads to elevated mis-segregation and aneuploidy of a subset of chromosomes, particularly affecting chromosomes 1 and 2. Unexpectedly, we find that a period of mitotic delay weakens centromeric cohesion and promotes chromosome mis-segregation and that chromosomes 1 and 2 are particularly prone to suffer cohesion fatigue. Our findings demonstrate that inherent properties of individual chromosomes can bias chromosome mis-segregation and aneuploidy rates, with implications for studies on aneuploidy in human disease., Graphical Abstract, Highlights • Aneuploidy rates vary between chromosomes after drug-induced mis-segregation • Chromosomes 1 and 2 comprise a large proportion of anaphase lagging chromosomes • Mitotic delay and cohesion fatigue drive chromosome mis-segregation • Chromosomes 1 and 2 are particularly prone to cohesion fatigue, Worrall et al. show that individual human chromosomes can respond differently to defects in mitosis that lead to chromosome mis-segregation. Following nocodazole washout, chromosomes 1 and 2 are particularly prone to a weakening of centromeric cohesion and elevated rates of chromosome lagging during anaphase.

Photodynamic therapy (PDT) is a cancer treatment involving systemic administration of a tumor-localizing photosensitizer; this, when activated by the appropriate wavelength of light, interacts with molecular oxygen to form a toxic, short-lived species known as singlet oxygen, which is thought to mediate cellular death. Photofrin, a complex mixture of porphyrin oligomers has recently received FDA approval for the photodynamic treatment of esophageal and endobronchial carcinoma, but its photodynamic and toxicity profiles are far from ideal. In the present study we evaluated a series of porphyrin-based PSs, some of which newly synthesized by our group, with the aim to identify agents with more favorable characteristics. For the most effective compounds in the porphyrin series, chlorin analogs were also synthesized; for comparison, the screening also included Photofrin. Cytotoxicity studies were performed by the MTT assay on a cultured human colon adenocarcinoma cell line (HCT116); the results indicate that the 3,4,5-trimethoxyphenyl, 3OH- and 4OH-phenyl, and the sulfonamidophenyl derivatives are significantly more potent than Photofrin. Flow cytometric studies and fluorescence microscopy indicate that in PDT-treated HCT116 cells death occurs mainly by apoptosis. In summary, novel PSs described in the present study, belonging both to the porphyrin and chlorin series, have proven more effective than Photofrin in killing colon cancer cells in vitro; extending these observation to in vivo models, particularly regarding the deeper reaching chlorin derivatives, might lead to significant advances in the development of tumor PDT.

Two experiments examined some relationships between feeding schedule and two psychoactive drugs on the mouse-killing response in rats. Experiment 1 showed that the combination of a high dose of d-amphetamine (2.00 mg/kg) and food satiation effectively suppresses killing while either factor alone does not. Experiment 2 showed that the combination of a high dose of pilocarpine (30 mg/kg) and food deprivation induces a considerable percentage of Sprague-Dawley rats to kill mice while either variable alone does not.

The purpose of this study was to determine the effect of a computer-administered test on test anxiety and performance. The sample comprised twenty-six male and fourteen female college students enrolled in a developmental reading course at a private university. Subjects were randomly assigned to either a computerized or to a pencil-and-paper testing situation. Both groups were administered a revised version of the Test Anxiety Scale (TAS-R) and a sample of items from the California Short-Form Test of Mental Maturity (CMM). Mean differences between groups on the TAS-R and the CMM were tested for significance using t-tests. The results indicated significant differences in anxiety level, t(38) = −1.87, p < .05, and test performance, t(38) = 2.68, p < .01. It was concluded that computer-administered testing can potentially increase test anxiety and depress test performance for examinees who are relatively unfamiliar with computers.