Traumatic spinal cord injury is characterized by an immediate, irreversible loss of tissue at the lesion site, as well as a secondary expansion of tissue damage over time. Although secondary injury should, in principle, be preventable, no effective treatment options currently exist for patients with acute spinal cord injury (SCI). Excessive release of ATP by the traumatized tissue, followed by activation of high-affinity P2X7 receptors, has previously been implicated in secondary injury, but no clinically relevant strategy by which to antagonize P2X7 receptors has yet, to the best of our knowledge, been reported. Here we have tested the neuroprotective effects of a systemically administered P2X7R antagonist, Brilliant blue G (BBG), in a weight-drop model of thoracic SCI in rats. Administration of BBG 15 min after injury reduced spinal cord anatomic damage and improved motor recovery without evident toxicity. Moreover, BBG treatment directly reduced local activation of astrocytes and microglia, as well as neutrophil infiltration. These observations suggest that BBG not only protected spinal cord neurons from purinergic excitotoxicity, but also reduced local inflammatory responses. Importantly, BBG is a derivative of a commonly used blue food color (FD&C blue No. 1), which crosses the blood-brain barrier. Systemic administration of BBG may thus comprise a readily feasible approach by which to treat traumatic SCI in humans.astrocytes ͉ inflammation ͉ microglia ͉ motor neurons ͉ purinergic signaling

ObjectivesTo assess the direct and indirect effects of patient or caregiver factors on caregiver burden of caring for community-residing people with mild Alzheimer’s disease (AD).MethodsWe conducted a cross-sectional study of patients diagnosed with AD from two hospitals and three communities in Taiyuan, China and their caregivers. For this survey, 200 patients with mild AD and their caregivers were selected. Caregivers were asked to provide sociodemographic information including age, gender, relationship with the patient, level of education, and number of contact hours per week with the patient. Caregiver burden was assessed using the Caregivers Burden Inventory. The caregivers also completed other measures including the Positive Aspects of Caregiving, the Family Adaptation, Partnership, Growth, Affection, and Resolve, and the Social Support Rating Scale. The patients with AD completed the Montreal Cognitive Assessment; their caregivers completed the Activities of Daily Living Scale and a questionnaire about the patients’ Behavioral and Psychological symptoms of Dementia. The main outcome in this study was caregiver burden. The care receivers’ level of cognitive function, physical function, and behavioral problems were treated as original stress; the primary appraisal variable was measured as the number of hours of caregiving in the previous week reported by the caregiver. Mediator variables included perceived social support, family function, and caregiving experience. Path analysis was used to build the interrelationship among caregiver burden and patient or caregiver factors.ResultsA lower level of cognitive function in patients (r = −0.28, p<0.001) and longer hours of caregiving (r = 0.17, p = 0.019) were related to increased caregiver burden. Greater social support (r = −0.23, p<0.001), family function (r = −0.17, p = 0.015) and caregiving experience (r = −0.16, p = 0.012) were related to decreased caregiver burden. Social support (r = 0.16, p = 0.040) and family function (r = 0.25, p = 0.002) were directly related to patients’ level of cognitive functioning, but were mediator factors between level of cognitive function in patients and caregiver burden. Similarly, social support was a mediator factor between patients' daily function (r = −0.23, p = 0.004) and caregiver burden; while caregiving experience mediated the link between behavioral and psychological symptoms in patients (r = 0.36, p<0.001) and caregiver burden.ConclusionLevel of cognitive function and hours of caregiving were directly related to caregiver's burden. Social support, family function and caregiving experience could mediate the relationship between patient factors and caregiver burden. Focusing on patient factors and promoting caregiver care will be helpful in lowering the perceived burden of caregiving.

Understanding the interaction between soluble factors and cells in the cellular microenvironment is critical to understanding a wide range of diseases. Microchannel culture systems provide a tool for separating diffusion and convection based transport making possible controlled studies of the effects of soluble factors in the cellular microenvironment. In this paper we compare the proliferation kinetics of cells in traditional culture flasks to those in microfluidic channels, and explore the relationship between microchannel geometry and cell proliferation. PDMS (polydimethylsiloxane) microfluidic channels were fabricated using micromolding methods. Fall armyworm ovarian cells (Sf9) were homogeneously seeded in a series of different sized microchannels and cultured under a no flow condition. The proliferation rates of Sf9 cells in all of the microchannels were slower than in the flask culture over the first 24 h of culture. The proliferation rates in the microchannels then continuously decreased reaching 5% of that in the flasks over the next 48 h and maintained this level for 5 days. This growth inhibition was reversible and influenced only by the cell seeding density and the channel height but not the channel length or width. One possible explanation for the observed dimension-dependent cell proliferation is the accumulation of different functional molecules in the diffusion dominant microchannel environment. This study provides insights into the potential effects of the diffusion of soluble factors and related effects on cell behavior in microenvironments relevant to the emerging use of microchannel culture systems.

Gibberellic acid (GA) can regulate many plant developmental processes. GAST1 has been identified as a GA-stimulated transcript, and Arabidopsis GAST-like genes are known to constitute the GASA family. However, the functions of most GASA genes are not clear at present. In this study, the function of GASA14, a member of the GASA family, was investigated. GASA14 expression was upregulated by GA and downregulated by the transcriptional regulators that repress GA responses, the DELLA proteins GAI and RGA. Phenotypic analysis showed that growth of the GASA14 null mutant (gasa14-1) line was retarded, and the growth of the 35S::GASA14 lines were promoted in young plants. Furthermore, seed germination of the gasa14-1 plants showed more sensitivity to paclobutrazol (an inhibitor of GA biosynthesis) than Columbia (Col) plants, suggesting that GASA14 is required for GA-dependent responses. Analysis of the responses of the gasa14-1 and 35S::GASA14 lines to abscisic acid (ABA) and salt revealed that germination and seedling establishment of gasa14-1 were poorer than those of Col plants and that the 35S::GASA14 lines were more resistant to ABA and salt. Further analysis showed that overexpression of GASA14 could suppress reactive oxygen species (ROS) accumulation. Taken together, these results demonstrated that GASA14 regulates leaf expansion and abiotic stress resistance by modulating ROS accumulation. Because GASA14 contains both GASA (GA-stimulated in Arabidopsis) and PRP (proline-rich protein) domains, the PRP domain coding sequence was overexpressed in Col plants and it was found that the growth of the transgenic plants and the responses to ABA and salt were not altered. These results thus suggest that the GASA domain is necessary for the functions of GASA14.

The cellular microenvironment plays a critical role in shaping and directing the process of communication between the cells. Soluble signals are responsible for many cellular behaviors such as cell survival, proliferation and differentiation. Despite the importance of soluble signals, canonical methods are not well suited to the study of soluble factor interactions between multiple cell types. Macro-scale technology often puts cells into a convective environment that can wash away and dilute soluble signals from their targets, minimizing local concentrations of important factors. In addition, current methods such as transwells, require large numbers of cells and are limited to studying just two cell types. Here, we present data supporting the use of microchannels to study soluble factor signaling providing improved sensitivity as well as the ability to move beyond existing co-culture and conditioned medium paradigms. In addition, we present data suggesting that microculture can be used to unmask effects of population demographics. In this example the data support the hypothesis that a growth promoting subpopulation of cells exists in the mouse mammary gland.