Testing and implementing signal impact analysis in a regulatory setting: results of a pilot study.

BACKGROUND AND AIM: Statistical signal detection methods such as proportional reporting ratios (PRRs) detect many drug safety signals when applied to databases of spontaneous suspected adverse drug reactions (ADRs). Impact analysis is a tool that was developed as an aid to prioritisation of such signals. This paper describes a pilot project whereby impact analysis was simultaneously introduced into practice in a regulatory setting and tested in comparison with the existing approach. METHODS: Impact analysis was run on signals detected during a 26-week period from the UK Adverse Drug Reactions On-line Information Tracking (ADROIT) database of spontaneous ADRs that met minimum criteria (PRR>or=3.0, chi2>or=4.0 and >or=3 reported cases) and related to established drugs (i.e. those that have been available for at least 2 years and no longer carry the 'black triangle' symbol). The current method of signal prioritisation (i.e. the collective judgement at a weekly meeting) was initially performed without knowledge of the findings of impact analysis. Subsequently, the meeting was presented with the findings and, where appropriate, given the opportunity to reconsider the judgement made. The categories arising from the two methods were compared and the ultimate action recorded. Inter-observer variation between scientists performing impact analysis was also assessed. RESULTS: Eighty-six separate signals were analysed by impact analysis, of which 5% were categorised as high priority (A), 14% as requiring further information (B), 31% as low priority (C) and 50% as no action required (D). In general, the new method tended to give a higher level of priority to signals than the existing approach. Overall, there was 59% agreement between the impact analysis and the collective judgement at the meetings (kappa statistic=0.30). There was slightly greater agreement between impact analysis and the final action taken (kappa statistic=0.39), indicating that the findings of an impact analysis had an influence on the outcome. Assessment of inter-observer variation demonstrated that the method is repeatable (kappa statistic for overall category=0.77). Almost 70% of those who participated in the pilot study believed that impact analysis represented an improvement in how signals were prioritised. CONCLUSIONS: Impact analysis is a repeatable method of signal prioritisation that tended to give a higher level of priority to signals than the standard approach and which had an influence on the ultimate outcome.     

Randomized trial of two intravenous schedules of the topoisomerase I inhibitor liposomal lurtotecan in women with relapsed epithelial ovarian cancer: a trial of the national cancer institute of Canada clinical trials group.

PURPOSE: Liposomal lurtotecan (OSI-211) is a liposomal formulation of the water-soluble topoisomerase I inhibitor lurtotecan (GI147211), which demonstrated superior levels of activity compared with topotecan in preclinical models. We studied two schedules of OSI-211 in a randomized design in relapsed ovarian cancer to identify the more promising of the two schedules for further study. PATIENTS AND METHODS: Eligible patients had measurable epithelial ovarian, fallopian, or primary peritoneal cancer that was recurrent after one or two prior regimens of chemotherapy. Patients were randomly assigned to receive either arm A (OSI-211 1.8 mg/m(2)/d administered by 30-minute intravenous infusion on days 1, 2, and 3 every 3 weeks) or arm B (OSI-211 2.4 mg/m(2)/d administered by 30-minute intravenous infusion on days 1 and 8 every 3 weeks). The primary outcome measure was objective response, which was confirmed by independent radiologic review, and a pick the winner statistical design was used to identify the schedule most likely to be superior. RESULTS: Eighty-one patients were randomized between October 2000 and September 2001. The hematologic toxic effects were greater on arm A than on arm B (grade 4 neutropenia, 51% v 22%, respectively), as was febrile neutropenia (26% v 2.4%, respectively). Of the 80 eligible patients, eight patients (10%) had objective responses; six responders (15.4%; 95% CI, 6% to 30%) were in arm A and two responders (4.9%; 95% CI, 1% to 17%) were in arm B. CONCLUSION: The OSI-211 daily for 3 days intravenous schedule met the statistical criteria to be declared the winner in terms of objective response. This schedule was also associated with more myelosuppression than the schedule of OSI-211 administered in arm B.     

Comprehensive analysis of CDKN2A status in microdissected urothelial cell carcinoma reveals potential haploinsufficiency, a high frequency of homozygous co-deletion and associations with clinical phenotype.

PURPOSE: There are significant differences in reported frequencies, modes of inactivation, and clinical significance of CDKN2A in urothelial cell carcinoma (UCC). We aimed to address these issues by investigating all possible modes of inactivation and clinicopathologic variables in a single tumor panel. EXPERIMENTAL DESIGN: Fifty microdissected UCCs were examined. CDKN2A gene dosage (quantitative real-time PCR), allelic status (microsatellite analysis), hypermethylation (methylation-specific PCR), mutation status (denaturing high-performance liquid chromatography and sequencing), protein expression (immunohistochemistry), and clinicopathologic variables (stage, grade, and disease recurrence during follow-up) were assessed. RESULTS: Exon 2 was underrepresented in 20 of 46 (43%) and exon 1beta in 21 of 46 (46%) of cases. Underrepresentation of exon 2 was accompanied by loss of heterozygosity (LOH) of 9p in 6 of 18 (30%) and of exon 1beta in 11 of 19 assessable cases (58%). Overall, LOH of 9p was identified in 15/41 (37%). Homozygous deletion of exons 2 and 1beta was detected in 16 of 46 (35%) and 10 of 46 tumors (22%), respectively. Co-deletion was most common, but exon 2-specific homozygous deletion was also detected. In tumors without homozygous deletion, p16 promoter hypermethylation was detected in 1 of 18 (6%). Hypermethylation of the p14ARF promoter or mutations in CDKN2A were not observed. Homozygous deletion of exon 2 or LOH on 9p were associated with invasion. Homozygous deletion of exon 2 or exon 1beta was associated with recurrent disease. CONCLUSIONS: These results confirm CDKN2A as a clinically relevant target for inactivation in UCC and show that the true frequency of alteration is only revealed by comprehensive analysis. Our results suggest that CDKN2A may be haploinsufficient in human cancer.     

International consensus statement on attention-deficit/hyperactivity disorder (ADHD) and disruptive behaviour disorders (DBDs): clinical implications and treatment practice suggestions.

Researchers and clinicians worldwide share concerns that many youngsters with attention-deficit/hyperactivity disorder (ADHD) and/or disruptive behaviour disorders (DBDs) do not receive appropriate treatment despite availability of effective therapies. At the request of Johnson and Johnson (sponsor), 11 international experts in child and adolescent psychiatry were selected by Professor Stan Kutcher (chair) to address these concerns. This paper describes the experts' consensus conclusions, including treatment practice suggestions for physicians involved in the early treatment of youngsters with ADHD (or hyperkinetic disorder, in countries preferring this classification) and/or DBDs internationally: suggested first-line treatment for ADHD without comorbidity is psychostimulant medication aided by psychosocial intervention. For ADHD with comorbid conduct disorder (CD), psychosocial intervention combined with pharmacotherapy is suggested. For primary CD, suggested first-line treatment is psychosocial intervention, with pharmacotherapy considered as an 'add-on' when aggression/impulsivity is marked and persistent. Pharmacotherapy requires careful titration; full-day coverage is the suggested goal. Regular long-term follow-up is recommended.     

Increased susceptibility to adult paraoxon exposure in mice neonatally exposed to nicotine.

Low-dose exposure of neonatal mice to nicotine has earlier been shown to induce an altered behavioral response to nicotine in adulthood. Organophosphorus insecticides are known to affect the cholinergic system by inhibition of acetylcholinesterase. This study was undertaken to investigate whether neonatal exposure to nicotine makes mice more susceptible to a known cholinergic agent. Neonatal, 10-day-old, male mice were exposed to nicotine-base (33 microg/kg body weight) or saline s.c. twice daily on five consecutive days. At 5 months of age the animals were exposed to paraoxon (0.17 or 0.25 mg/kg body weight [29% and 37% inhibition of cholinesterase, respectively]) or saline sc every second day for 7 days. Before the first paraoxon injection, the animals were observed for spontaneous motor behavior. The spontaneous motor behavior test did not reveal any differences in behavior between the treatment groups. Immediately after the spontaneous behavior test, the animals received the first injection of paraoxon and were observed for acute effects of paraoxon on spontaneous motor behavior. The acute response to paraoxon in the spontaneous motor behavior test was a decreased level of activity in mice neonatally exposed to nicotine. Control animals showed no change in activity. Two months after the paraoxon treatment, the animals were again tested for spontaneous motor behavior. Animals neonatally exposed to nicotine and exposed to paraoxon as adults showed a deranged spontaneous motor behavior, including hyperactivity and lack of habituation.     

Centredness in health care: A systematic overview of reviews

IntroductionThe introduction of effective, evidence‐based approaches to centredness in health care is hindered by the fact that research results are not easily accessible. This is partly due to the large volume of publications available and because the field is closely linked to and in some ways encompasses adjoining fields of research, for example, shared decision making and narrative medicine. In an attempt to survey the field of centredness in health care, a systematic overview of reviews was conducted with the purpose of illuminating how centredness in health care is presented in current reviews.MethodsSearches for relevant reviews were conducted in the databases PubMed, Scopus, Cinahl, PsychINFO, Web of Science and EMBASE using terms connected to centredness in health care. Filters specific to review studies of all types and for inclusion of only English language results as well as a time frame of January 2017–December 2018, were applied.ResultsThe search strategy identified 3697 unique reviews, of which 31 were included in the study. The synthesis of the results from the 31 reviews identified three interrelated main themes: Attributes of centredness (what centredness is), Translation from theory into practice (how centredness is done) and Evaluation of effects (possible ways of measuring effects of centredness). Three main attributes of centeredness found were: being unique, being heard and shared responsibility. Aspects involved in translating theory into practice were sufficient prerequisites, strategies for action and tools used in safeguarding practice. Further, a variety and breadth of measures of effects were found in the included reviews.ConclusionsOur synthesis demonstrates that current synthesized research literature on centredness in health care is broad, as it focuses both on explorations of the conceptual basis and the practice, as well as measures of effects. This study provides an understanding of the commonalities identified in the reviews on centredness in healthcare overall, ranging from theory to practice and from practice to evaluation.Patient or Public ContributionPatient representatives were involved during the initiation of the project and in decisions about its focus, although no patient or public representatives made direct contributions to the review process.     

Outbreak of Salmonella Newport linked to imported frozen cooked crayfish in dill brine,Sweden, July to November 2019

In autumn 2019, the Public Health Agency of Sweden identified a cluster of Salmonella Newport cases by whole genome sequencing (WGS). Cases’ distribution in place and time indicated a nation-wide ongoing outbreak. An investigation was initiated to identify the source and prevent further cases. We conducted a case–case study based on notified salmonellosis cases and a Salmonella trawling questionnaire, comparing 20 outbreak cases and 139 control cases. Food exposures were compared by adjusted odds ratios (aOR) with 95% confidence interval (CI) using logistic regression. Implicated foods were sampled. Outbreak cases were more likely to have consumed crayfish (aOR = 26; 95% CI: 6.3–105). One specific brand of imported frozen, pre-cooked whole crayfish in dill brine was identified as the source. Salmonella Newport was later detected in different batches from retail and in one sample from border control. Isolates from food samples clustered with the human outbreak strain by WGS. Although the retailer made a complete recall, two more cases were identified long afterwards. This investigation demonstrated the successful use of a case–case study and targeted microbiological testing to identify the source. The immediate action taken by the retailer was important to confirm the source and stop the outbreak.     

Mechanical coupling of supracellular stress amplification and tissue fluidization during exit from quiescence

Cellular quiescence is a state of reversible cell cycle arrest that is associated with tissue dormancy. Timely regulated entry into and exit from quiescence is important for processes such as tissue homeostasis, tissue repair, stem cell maintenance, developmental processes, and immunity. However, little is known about processes that control the mechanical adaption to cell behavior changes during the transition from quiescence to proliferation. Here, we show that quiescent human keratinocyte monolayers sustain an actinomyosin-based system that facilitates global cell sheet displacements upon serum-stimulated exit from quiescence. Mechanistically, exposure of quiescent cells to serum-borne mitogens leads to rapid amplification of preexisting contractile sites, leading to a burst in monolayer tension that subsequently drives large-scale displacements of otherwise motility-restricted monolayers. The stress level after quiescence exit correlates with the level of quiescence depth at the time of activation, and a critical stress magnitude must be reached to overcome the cell sheet displacement barrier. The study shows that static quiescent cell monolayers are mechanically poised for motility, and it identifies global stress amplification as a mechanism for overcoming motility restrictions in confined confluent cell monolayers.

Quiescence refers to a state of cell cycle arrest in which cells are retained in a standby mode, ready to re-enter the cell cycle upon activation by a given physiological stimuli. The pool of quiescent cells in the human body is typically represented by tissue-specific stem and progenitor cells, naive immune cells, fibroblasts, and epithelial cells (1, 2). In addition, certain cancer cells have the ability to evade cancer therapy by entering a dormant quiescence-like state (1, 2). Accordingly, careful regulation of entry into and exit out of quiescence is important for several physiological processes such as tissue homeostasis and repair, stem cell maintenance, immunity, reproduction, and development (1, 2).During homeostasis, the balance between quiescent and proliferating cells is controlled by constituents of the microenvironment such as soluble factors, extracellular matrix components, blood vessels, and neighboring cells. On the other hand, during episodes that require extensive tissue renewal and remodeling, for example after injury, coordinated stimulation of quiescent cells into proliferation is facilitated by increased exposure to blood-borne and cell-secreted mitogens through local inflammatory responses such as increased blood flow, increased vascular permeability (vasodilation), and immune cell recruitment (3, 4). Accordingly, a commonly used methodology for studies of quiescence in cultured mammalian cells involves consecutive treatments with serum-free and serum-containing growth medium (1).Quiescent cells are required to maintain a high level of preparedness in order to facilitate rapid activation of specialized cell functions once cell division is stimulated. In agreement with this, quiescent stem cells and naive immune cells have been shown to possess multiple epigenetic and posttranslation mechanisms that facilitate the rapid expression of linage-specific genes following stimulation of quiescence exit (2, 5–14). However, little is known about mechanical forces that facilitate adaptation to cell cycle–activated behaviors.Quiescence exit is frequently associated with activation of cell motility. For example, quiescent stem and naive immune cells migrate out of their niches in response to cell cycle activation in order to support tissue homeostasis, repopulate injured tissue, or to perform immune surveillance at distal locations (15–18). In addition, reawakening of dormant quiescent cancer cells can cause tumor relapse and formation of metastases years after remission (19). In multilayered epithelial tissue, like the skin, exit from quiescence during homeostasis is associated with lateral migration to suprabasal regions, while skin injury evokes massive reawakening of basally localized keratinocytes concomitant with activation of cell sheet displacement by collective migration to restore damaged epidermal surfaces (20–23). The strong correlation between quiescence exit and cell migration in multiple physiological settings suggests the existence of mechanisms that link quiescence exit to activation of cell motility.The dynamics of epithelial collectives is largely regulated by mechanical forces generated through cell–cell interactions as well as interactions between cells and the extracellular environment (24). Key components involved in controlling these forces are cytoskeletal components such as actinomyosin and adhesion complexes such as adherent junctions and focal adhesion complexes (25). Additional factors that have been reported to influence the dynamic behavior of epithelial monolayers include the presence of epithelial edges (24, 26), mechanical stretching or compression (27, 28), expression of the endosomal Rab5 protein (29), exposure of cells to growth factors (30–32), local changes in cell shape (33), and the ability of cells to undergo neighbor exchange (34, 35). In addition, recent studies have also identified a functional link between cell cycle progression and force fluctuation leading to dynamic behavior of cultured epithelial monolayers (36, 37).In this study, we have investigated a mechanical link between quiescence exit and activation of large-scale cell sheet displacements. Using traction force microscopy (TFM), we found that confluent cell monolayers install an actinomyosin-based system during quiescence that produces a coordinated burst of contractile forces and intercellular tension across the epithelial monolayer immediately following exposure to serum-borne mitogens. By combining experiments and theoretical modeling, we show that the amplified forces are essential for driving coordinated cell sheet displacements within otherwise motility-restricted cell monolayers. Furthermore, the magnitude of mechanical forces created during quiescence exit and the extent of cell sheet displacement correlate with quiescence depth. Our study provides evidence that quiescent keratinocyte monolayers possess mechanical preparedness for motility and establish monolayer stress amplification as a strategy for overcoming the motility barrier in confined cell sheets.