Effects of an online mindfulness-based program for parents of children with attention deficit/hyperactivity disorder: a pilot, mixed methods study.

Objectives: Online mindfulness-based program (MBP) for parents and families especially in clinical population is limited. Engagement and significant dropout are major issues in MBP implementation. This pilot study examined the effects of an online mindfulness-based program (MBP) on parents of children with Attention Deficit/Hyperactivity Disorder (ADHD). Methods: A mixed methods study was applied to evaluate the effects of the MBP. A total of 43 parents were recruited and were randomly assigned into intervention group and waitlist control group. The online MBP lasted for 28 days, including 20 psychoeducation videos, homework audio guidance, and four instructor-led online group meetings. Purposive sampling was used to recruit parents who completed the program to share their experiences and suggestions for improving the program in semi-structured online interviews. Results: Quantitative data showed that participants from the online MBP reported a medium to large effect on the reduction of child ADHD symptoms. In semi-structured interviews, participants reported positive experiences in their help seeking intention, and personal changes, such as emotion regulation and quality attention to their children. Participants further made suggestions for improvement. Conclusions: The effect of online MBP is promising, and the program should be conducted. A large scale randomized controlled trial should be conducted to investigate the effects of MBP in clinical populations. Clinical trial registration: ClinicalTrials.gov NCT05480423.

Effects of a Mindful Parenting Workshop for Parents of Adolescents and Young Adults Following Social Unrest in Hong Kong.

OBJECTIVES: The social unrest that began in Hong Kong in 2019 became a threat to public mental health, such as for depression and post-traumatic stress disorders. A supportive family environment is the most effective protective factor for mental health problems for young people who are exposed to conflict and violence. This study investigated the outcomes of a brief mindful parenting workshop on parent mental health and family functioning. METHODS: Using a randomized controlled trial design, 54 parents of adolescents and young adults were randomized into intervention group and waitlist control group. Depression, anxiety, post-traumatic stress symptoms, negative emotions, family functioning, and family conflicts were measured at baseline (pretest), following training, and at 3-month follow-up. RESULTS: We found a significant improvement in family functioning among parents in the intervention group when compared to those parents in the control group (F [1, 51] = 4.41, p = .04). When we further controlled the child-initiated physical conflict as covariate, a significant reduction of self-rated levels of depressive symptoms was found in the parents from the intervention group when compared to the parents in the control group (F [1, 49] = 5.14, p = .03). CONCLUSIONS: We found preliminary evidence that a brief mindful parenting workshop can strengthen parent and family mental health at times of social unrest. TRIAL REGISTRATION: ClinicalTrials.gov (NCT04427683).

Microscale arrays for the profiling of start and stop signals coordinating human-neutrophil swarming.

Neutrophil swarms protect healthy tissues by sealing off sites of infection. In the absence of swarming, microbial invasion of surrounding tissues can result in severe infections. Recent observations in animal models have shown that swarming requires rapid neutrophil responses and well-choreographed neutrophil migration patterns. However, in animal models physical access to the molecular signals coordinating neutrophil activities during swarming is limited. Here, we report the development and validation of large microscale arrays of zymosan-particle clusters for the study of human neutrophils during swarming ex vivo. We characterized the synchronized swarming of human neutrophils under the guidance of neutrophil-released chemokines, and measured the mediators released at different phases of human-neutrophil swarming against targets simulating infections. We found that the network of mediators coordinating human-neutrophil swarming includes start and stop signals, proteolytic enzymes and enzyme inhibitors, as well as modulators of activation of other immune and non-immune cells. We also show that the swarming behavior of neutrophils from patients following major trauma is deficient and gives rise to smaller swarms than those of neutrophils from healthy individuals.

Balancing Patient Autonomy, Surrogate Decision Making, and Physician Non-Maleficence When Considering Do-Not-Resuscitate Orders: An Ethics Case Analysis.

[Full article available at http://rimed.org/rimedicaljournal-2017-10.asp].

A Worldwide Competition to Compare the Speed and Chemotactic Accuracy of Neutrophil-Like Cells.

Chemotaxis is the ability to migrate towards the source of chemical gradients. It underlies the ability of neutrophils and other immune cells to hone in on their targets and defend against invading pathogens. Given the importance of neutrophil migration to health and disease, it is crucial to understand the basic mechanisms controlling chemotaxis so that strategies can be developed to modulate cell migration in clinical settings. Because of the complexity of human genetics, Dictyostelium and HL60 cells have long served as models system for studying chemotaxis. Since many of our current insights into chemotaxis have been gained from these two model systems, we decided to compare them side by side in a set of winner-take-all races, the Dicty World Races. These worldwide competitions challenge researchers to genetically engineer and pharmacologically enhance the model systems to compete in microfluidic racecourses. These races bring together technological innovations in genetic engineering and precision measurement of cell motility. Fourteen teams participated in the inaugural Dicty World Race 2014 and contributed cell lines, which they tuned for enhanced speed and chemotactic accuracy. The race enabled large-scale analyses of chemotaxis in complex environments and revealed an intriguing balance of speed and accuracy of the model cell lines. The successes of the first race validated the concept of using fun-spirited competition to gain insights into the complex mechanisms controlling chemotaxis, while the challenges of the first race will guide further technological development and planning of future events.

Microfluidic mazes to characterize T-cell exploration patterns following activation in vitro.

The migration of T-cell subsets within peripheral tissues is characteristic of inflammation and immunoregulation. In general, the lymphocyte migratory response is assumed directional and guided by local gradients of chemoattractants and/or chemorepellents. However, little is known about how cells explore their tissue environment, and whether lymphocyte activation may influence speed and exploratory patterns of migration. To probe migration patterns by T-cells we designed a microfluidic maze device that replicates critical features of a tissue-like microenvironment. We quantified the migration patterns of unstimulated and mitogen-activated human T-cells at single cell resolution and found significant differences in exploration within microfluidic mazes. While unstimulated lymphocytes migrated in a directed manner, activated T-cells migrated through large areas of the mazes in an exploratory pattern in response to the chemoattractants RANTES (CCL5) and IP-10 (CXCL10). The analysis of migration enabled by the microfluidic devices help develop new methods for determining how human circulating T-cells function in vivo to seek out antigens in health and disease states.

A neutrophil treadmill to decouple spatial and temporal signals during chemotaxis.

After more than 50 years of debates, the role of spatial and temporal gradients during cell chemotaxis is still a contentious matter. One major challenge is that when cells move in response to a heterogeneous chemical environment they are exposed to both spatial and temporal concentration changes. Even in the presence of perfectly stable chemical gradients, moving cells experience temporal changes of concentration simply by moving between locations with different chemical concentrations in a heterogeneous environment. Thus, the effects of the spatial and temporal stimuli cannot be dissociated and studied independently, hampering progress towards understanding the mechanisms of cell chemotaxis. Here we employ microfluidic and other engineering tools to build a system that accomplishes a function analogous to a treadmill at the cellular scale, holding a moving cell at a specified, unchanging location in a chemical gradient. Using this system, we decouple the spatial and temporal gradients around moving human neutrophils and find that temporal gradients are necessary for the directional persistence of human neutrophils during chemotaxis. Our results suggest that temporal chemoattractant changes are important during neutrophil migration and should be taken into account when deciphering the signalling pathways of cell chemotaxis.

Microfluidic platform for the quantitative analysis of leukocyte migration signatures.

Leukocyte migration into tissues is characteristic of inflammation. It is usually measured in vitro as the average displacement of populations of cells towards a chemokine gradient, not acknowledging other patterns of cell migration. Here, we designed and validated a microfluidic migration platform to simultaneously analyse four qualitative migration patterns: chemoattraction, -repulsion, -kinesis and -inhibition, using single-cell quantitative metrics of direction, speed, persistence and fraction of cells responding. We find that established chemokines, complement component 5a and IL-8 induce chemoattraction and repulsion in equal proportions, resulting in the dispersal of cells. These migration signatures are characterized by high persistence and speed and are independent of the chemokine dose or receptor expression. Furthermore, we find that twice as many T lymphocytes migrate away than towards stromal cell-derived factor 1 and their directional migration patterns are not persistent. Overall, our platform helps discover migratory signature responses and uncovers an avenue for precise characterization of leukocyte migration and therapeutic modulators.

Collective and individual migration following the epithelial-mesenchymal transition.

During cancer progression, malignant cells in the tumour invade surrounding tissues. This transformation of adherent cells to a motile phenotype has been associated with the epithelial-mesenchymal transition (EMT). Here, we show that EMT-activated cells migrate through micropillar arrays as a collectively advancing front that scatters individual cells. Individual cells with few neighbours dispersed with fast, straight trajectories, whereas cells that encountered many neighbours migrated collectively with epithelial biomarkers. We modelled these emergent dynamics using a physical analogy to phase transitions during binary-mixture solidification, and validated it using drug perturbations, which revealed that individually migrating cells exhibit diminished chemosensitivity. Our measurements also indicate a degree of phenotypic plasticity as cells interconvert between individual and collective migration. The study of multicellular behaviours with single-cell resolution should enable further quantitative insights into heterogeneous tumour invasion.

On-demand, competing gradient arrays for neutrophil chemotaxis.

Neutrophils are the most abundant type of white blood cells in the circulation, protecting the body against pathogens and responding early to inflammation. Although we understand how neutrophils respond to individual stimuli, we know less about how they prioritize between competing signals or respond to combinational signals. This situation is due in part to the lack of adequate experimental systems to provide signals in controlled spatial and temporal fashion. To address these limitations, we designed a platform for generating on-demand, competing chemical gradients and for monitoring neutrophil migration. On this platform, we implemented forty-eight assays generating independent gradients and employed synchronized valves to control the timing of these gradients. We observed faster activation of neutrophils in response to fMLP than to LTB4 and unveiled for the first time a potentiating effect for fMLP during migration towards LTB4. Our observations, enabled by the new tools, challenge the current paradigm of inhibitory competition between distinct chemoattractant gradients and suggest that human neutrophils are capable of complex integration of chemical signals in their environment.

Retrotaxis of human neutrophils during mechanical confinement inside microfluidic channels.

The current paradigm of unidirectional migration of neutrophils from circulation to sites of injury in tissues has been recently challenged by observations in zebrafish showing that neutrophils can return from tissues back into the circulation. However, the relevance of these observations to human neutrophils remains unclear, the forward and reverse migration of neutrophils is difficult to quantify, and the precise conditions modulating the reverse migration cannot be isolated. Here, we designed a microfluidic platform inside which we observed human neutrophil migration in response to chemoattractant sources inside channels, simulating the biochemical and mechanical confinement conditions at sites of injury in tissues. We observed that, after initially following the direction of chemoattractant gradients, more than 90% of human neutrophils can reverse their direction and migrate persistently and for distances longer than one thousand micrometers away from chemoattractant sources (retrotaxis). Retrotaxis is enhanced in the presence of lipoxin A4 (LXA4), a well-established mediator of inflammation resolution, or Tempol, a standard antioxidant. Retrotaxis stops after neutrophils encounter targets which they phagocytise or on surfaces presenting high concentrations of fibronectin. Our microfluidic model suggests a new paradigm for neutrophil accumulation at sites of inflammation, which depends on the balance of three simultaneous processes: chemotaxis along diffusion gradients, retrotaxis following mechanical guides, and stopping triggered by phagocytosis.

Microfluidic chemotaxis platform for differentiating the roles of soluble and bound amyloid-ß on microglial accumulation.

Progressive microglial accumulation at amyloid-ß (Aß) plaques is a well-established signature of the pathology of Alzheimer's disease, but how and why microglia accumulate in the vicinity of Aß plaques is unknown. To understand the distinct roles of Aß on microglial accumulation, we quantified microglial responses to week-long lasting gradients of soluble Aß and patterns of surface-bound Aß in microfluidic chemotaxis platforms. We found that human microglia chemotaxis in gradients of soluble Aß42 was most effective at two distinct concentrations of 23 pg.mL(-1) and 23 ng.mL(-1) Aß42 in monomers and oligomers. We uncovered that while the chemotaxis at higher Aß concentrations was exclusively due to Aß gradients, chemotaxis at lower concentrations was enhanced by Aß-induced microglial production of MCP-1. Microglial migration was inhibited by surface-bound Aß42 in oligomers and fibrils above 45 pg.mm(-2). Better understanding of microglial migration can provide insights into the pathophysiology of senile plaques in AD.

Microfluidic chambers for monitoring leukocyte trafficking and humanized nano-proresolving medicines interactions.

Leukocyte trafficking plays a critical role in determining the progress and resolution of inflammation. Although significant progress has been made in understanding the role of leukocyte activation in inflammation, dissecting the interactions between different leukocyte subpopulations during trafficking is hampered by the complexity of in vivo conditions and the lack of detail of current in vitro assays. To measure the effects of the interactions between neutrophils and monocytes migrating in response to various chemoattractants, at single-cell resolution, we developed a microfluidic platform that replicates critical features of focal inflammation sites. We integrated an elastase assay into the focal chemotactic chambers (FCCs) of our device that enabled us to distinguish between phlogistic and nonphlogistic cell recruitment. We found that lipoxin A(4) and resolvin D1, in solution or incorporated into nano-proresolving medicines, reduced neutrophil and monocyte trafficking toward leukotriene B(4). Lipoxin A(4) also reduced the elastase release from homogenous and heterogenous mixtures of neutrophils and monocytes. Surprisingly, the effect of resolvin D1 on heterogenous mixtures was antisynergistic, resulting in a transient spike in elastase activity, which was quickly terminated, and the degraded elastin removed by the leukocytes inside the FCCs. Therefore, the microfluidic assay provides a robust platform for measuring the effect of leukocyte interactions during trafficking and for characterizing the effects of inflammation mediators.

Biological network motif detection: principles and practice.

Network motifs are statistically overrepresented sub-structures (sub-graphs) in a network, and have been recognized as 'the simple building blocks of complex networks'. Study of biological network motifs may reveal answers to many important biological questions. The main difficulty in detecting larger network motifs in biological networks lies in the facts that the number of possible sub-graphs increases exponentially with the network or motif size (node counts, in general), and that no known polynomial-time algorithm exists in deciding if two graphs are topologically equivalent. This article discusses the biological significance of network motifs, the motivation behind solving the motif-finding problem, and strategies to solve the various aspects of this problem. A simple classification scheme is designed to analyze the strengths and weaknesses of several existing algorithms. Experimental results derived from a few comparative studies in the literature are discussed, with conclusions that lead to future research directions.

Atypical antipsychotics and weight gain in Chinese patients: a comparison of olanzapine and risperidone.

OBJECTIVE: To compare the effect of olanzapine with that of risperidone on weight change among Chinese patients in Hong Kong. METHOD: The body weight of subjects maintained on olanzapine or risperidone treatment was recorded at the outpatient clinic of a teaching hospital. Pretreatment weight of the subjects was retrieved from case records. Subjects on olanzapine treatment were matched in sex, age, and diagnosis with those on risperidone treatment, and demographic and clinical data were analyzed. The study was conducted in May and June 2002. RESULTS: Twenty-eight olanzapine-risperidone matched pairs were studied. All were diagnosed with DSM-IV schizophrenia. In patients treated with olanzapine and risperidone, respectively, mean +/- SD duration of treatment with atypical neuroleptics was 103.5 +/- 47.4 weeks and 93.2 +/- 50.6 weeks (range, 21-255 weeks), and mean doses were 12.4 +/- 6.7 mg/day and 4.5 +/- 2.8 mg/day. The mean +/- SD weight gain of subjects on treatment with olanzapine and risperidone, respectively, was 8.34 +/- 5.97 kg (18.53 +/- 13.27 lb) and 2.74 +/- 8.09 kg (6.09 +/- 17.98 lb) with a statistically significant difference at p < .005. Lower baseline body weight and body mass index were associated with greater weight gain in both olanzapine- and risperidone-treated subjects. Gender, age, mean daily dose, and duration of treatment had no effect on weight change. CONCLUSION: Treatment with olanzapine was associated with significantly greater weight gain than treatment with risperidone in Chinese schizophrenia patients in Hong Kong. The effect of adjunctive anticonvulsant treatment on weight gain requires further study.