Interleukin-1beta and tumor necrosis factor-alpha are expressed by different subsets of microglia and macrophages after ischemic stroke in mice

Background  

Interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) are expressed by microglia and infiltrating macrophages following ischemic stroke. Whereas IL-1β is primarily neurotoxic in ischemic stroke, TNF-α may have neurotoxic and/or neuroprotective effects. We investigated whether IL-1β and TNF-α are synthesized by overlapping or segregated populations of cells after ischemic stroke in mice.     

Paradoxical stimulation and inhibition by protein kinase C modulating agents of lipopolysaccharide evoked production of tumour necrosis factor in human monocytes.

Human blood monocytes were activated by bacterial lipopolysaccharide endotoxin (LPS) (10 ng/ml) for cytotoxicity of WEHI-164 mouse fibrosarcoma cells, determined by release of 51Cr from WEHI-164 tumour cells incubated with monocyte supernatants. The chemotactic peptide N-formylmethionyl-leucyl-phenylalanine (FMLP) augmented LPS-induced cytotoxicity but had no effect alone. FMLP but not LPS stimulated phospholipase C (PLC), determined by the release of [3H]inositol phosphates. Addition of tumour promoter and protein kinase C stimulant, phorbol-12-myristate-13-acetate (PMA) at concentrations of 3 x 10(-10) M to 3 x 10(-9) M, resulted in an augmentation of 30-200% in LPS-evoked cytotoxicity. The effects of FMLP and PMA, like the effect of LPS alone, were completely blocked by antibody to recombinant human tumour necrosis factor-alpha (TNF-alpha), indicating that cytotoxicity induced by LPS, FMLP, and PMA were due solely to TNF release. Concentrations of PMA greater than 3 x 10(-9) M caused inhibition of TNF release. Okadaic acid (20 ng/ml), an inhibitor of phosphatases I and IIa, augmented the effects of LPS and the stimulatory effects of low levels of PMA, suggesting that phosphorylation was important in the actions of both LPS and PMA. The effects of LPS and of low levels of PMA were augmented by the protein kinase C (PKC) inhibitors H-7 (10-30 microM), staurosporine (2-10 nM) and calphostin C (0.1 microM). Higher concentrations of the inhibitors prevented LPS-evoked TNF release and its augmentation by low levels of PMA. However, they did not prevent the inhibition by high levels of PMA. One possible explanation for the results is that different isozymes of PKC may mediate the stimulatory as compared to the inhibitory effects of PKC on TNF production.     

Expression of the LspA1 and LspA2 proteins by Haemophilus ducreyi is required for virulence in human volunteers

Haemophilus ducreyi colocalizes with polymorphonuclear leukocytes and macrophages and evades phagocytosis during experimental infection of human volunteers. H. ducreyi contains two genes, lspA1 and lspA2, which encode predicted proteins of 456 and 543 kDa, respectively. Compared to its wild-type parent, an lspA1 lspA2 double mutant does not inhibit phagocytosis by macrophage and myelocytic cell lines in vitro and is attenuated in an experimental rabbit model of chancroid. To test whether expression of LspA1 and LspA2 was necessary for virulence in humans, six volunteers were experimentally infected. Each volunteer was inoculated with three doses (ranging from 85 to 112 CFU) of the parent (35000HP) in one arm and three doses (ranging from 60 to 822 CFU) of the mutant (35000HP Omega 12) in the other arm. The papule formation rates were 88% (95% confidence interval [95% CI], 76.8 to 99.9%) at 18 parent sites and 72% (95% CI, 44.4 to 99.9%) at 18 mutant sites (P = 0.19). However, papules were significantly smaller at mutant sites (mean size, 24.8 mm(2)) than at parent sites (mean size, 39.1 mm(2)) 24 h after inoculation (P = 0.0002). The pustule formation rates were 44% (95% CI, 5.8 to 77.6%) at parent sites and 0% (95% CI, 0 to 39.4%) at mutant sites (P = 0.009). With the caveat that biosafety regulations preclude testing of a complemented mutant in human subjects, these results indicate that expression of LspA1 and LspA2 facilitates the ability of H. ducreyi to initiate disease and to progress to pustule formation in humans.     

How are different types of continuity achieved? A mixed methods longitudinal study

BACKGROUND: In the context of developments in healthcare services that emphasise swift access to care, concern has been expressed about whether and how continuity of care, particularly interpersonal continuity, will continue to be achieved. AIM: To explore how patients regard and use primary care services in relation to continuity of provider and access to care, to identify factors that promote or hinder their success in achieving their preferences, and to describe what this means for how different types of continuity are achieved. DESIGN OF STUDY: Longitudinal, mixed methods. SETTING: Community in London and Leicester. METHOD: Purposive sample of 31 patients recruited from general practices, walk-in centres and direct advertising. Data collection involved in-depth interviews, consultation record booklets completed over 6 months and general practice records for the year including the study period. Data were analysed qualitatively. RESULTS: Four patterns were identified in the way patients used primary care. These were shaped by their own preferences, by the organisation and culture of their primary care practices, and by their own and their provider's efforts to achieve their preferences. Different configurations of these factors gave rise to different types of continuity. Patients were not always able to achieve the type they wanted. Patients with apparently similar consulting patterns could experience them differently. CONCLUSION: Within a programme of modernisation, policies that promote a commitment to meeting the preferences of different patients with flexibility and understanding are most likely to provide continued support for interpersonal and other types of continuity of care.     

Minimizing Therapeutic Differences Between Bilateral and Unilateral Nondominant ECT

Conflicting results continue to be reported for studies contrasting the therapeutic efficacy of bilateral and unilateral nondominant electroconvulsive therapy (ECT). At least in part, the therapeutic advantage for bilateral ECT observed by some investigators may be related to the use of nonoptimum unilateral ECT technique. Consideration of technique-related factors, such as stimulus electrode location, contact at the electrode-scalp interface, stimulus dosing, and seizure monitoring, will allow unilateral ECT to be carried out with maximal therapeutic potency.     

Racial Identity Clusters and Their Relation to Postpartum Maternal Functioning in Black Women

Maternal and Child Health Journal - Racial identity, which is the degree that individuals define themselves regarding their racial group membership, may influence the mental well-being of Black...     

Universal Mindfulness Training in Schools for Adolescents: a Scoping Review and Conceptual Model of Moderators,Mediators, and Implementation Factors

Prevention Science - There is evidence that universal school-based mindfulness training (SBMT) can have positive effects for young people. However, it is unknown who benefits most from such...