125 research outputs found
β2M Signals Monocytes Through Non-Canonical TGFβ Receptor Signal Transduction.
Rationale: Circulating monocytes can have pro-inflammatory or pro-reparative phenotypes. The
endogenous signaling molecules and pathways that regulate monocyte polarization in vivo are poorly
understood. We have shown that platelet derived beta-2 microglobulin (β2M) and transforming growth
factor beta (TGFβ) have opposing effects on monocytes by inducing inflammatory and reparative
phenotypes respectively, but each bind and signal through the same receptor. We now define the signaling
pathways involved.
Objective: To determine the molecular mechanisms and signal transduction pathways by which β2M and
TGFβ regulate monocyte responses both in vitro and in vivo.
Methods and Results: Wild-type (WT) and platelet specific β2M knockout (Plt-β2M-/-) mice were treated
intravenously with either β2M or TGFβ to increase plasma concentrations to those in cardiovascular
diseases. Elevated plasma β2M increased pro-inflammatory monocytes, while increased plasma TGFβ
increased pro-reparative monocytes. TGFβ receptor (TGFβR) inhibition blunted monocyte responses to
both β2M and TGFβ in vivo. Using imaging flow cytometry, we found that β2M decreased monocyte
SMAD2/3 nuclear localization, while TGFβ promoted SMAD nuclear translocation, but decreased noncanonical/
inflammatory (JNK and NFκB nuclear localization). This was confirmed in vitro using both
imaging flow cytometry and immunoblots. β2M, but not TGFβ, promoted ubiquitination of SMAD3 and
SMAD4, that inhibited their nuclear trafficking. Inhibition of ubiquitin ligase activity blocked noncanonical
SMAD-independent monocyte signaling and skewed monocytes towards a pro-reparative
monocyte response.
Conclusions: Our findings indicate that elevated plasma β2M and TGFβ dichotomously polarize
monocytes. Furthermore, these immune molecules share a common receptor, but induce SMAD-dependent
canonical signaling (TGFβ) versus non-canonical SMAD-independent signaling (β2M) in a ubiquitin ligase
dependent manner. This work has broad implications as β2M is increased in several inflammatory
conditions, while TGFβ is increased in fibrotic diseases.pre-print3451 K
16S-23S rRNA Internal Transcribed Spacer Region (ITS) Sequencing: A Potential Molecular Diagnostic Tool for Differentiating Lactococcus garvieae and Lactococcus petauri
Lactococcus garvieae is the etiological agent of lactococcosis, a clinically and economically significant infectious disease affecting farmed rainbow trout. L. garvieae had been considered the only cause of lactococcosis for a long time; however, L. petauri, another species of the genus Lactococcus, has lately been linked to the same disease. The genomes and biochemical profiles of L. petauri and L. garvieae have a high degree of similarity. Traditional diagnostic tests currently available cannot distinguish between these two species. The aim of this study was to use the transcribed spacer (ITS) region between 16S rRNA and 23S rRNA as a potential useful molecular target to differentiate L. garvieae from L. petauri, saving time and money compared to genomics methods currently used as diagnostic tools for accurate discrimination between these two species. The ITS region of 82 strains was amplified and sequenced. The amplified fragments varied in size from 500 to 550 bp. Based on the sequence, seven SNPs were identified that separate L. garvieae from L. petauri. The 16S-23S rRNA ITS region has enough resolution to distinguish between closely related L. garvieae and L. petauri and it can be used as a diagnostic marker to quickly identify the pathogens in a lactococcosis outbreak
Lung Megakaryocytes are Immune Modulatory Cells that Present Antigen to CD4+ T cells.
Although platelets are the cellular mediators of thrombosis, they are also immune cells. Platelets interact both directly and indirectly with immune cells, impacting their activation and differentiation, as well as all phases of the immune response. Megakaryocytes (Mks) are the cell source of circulating platelets, and until recently Mks were typically only considered bone marrow–resident (BM-resident) cells. However, platelet-producing Mks also reside in the lung, and lung Mks express greater levels of immune molecules compared with BM Mks. We therefore sought to define the immune functions of lung Mks. Using single-cell RNA sequencing of BM and lung myeloid-enriched cells, we found that lung Mks, which we term MkL, had gene expression patterns that are similar to antigen-presenting cells. This was confirmed using imaging and conventional flow cytometry. The immune phenotype of Mks was plastic and driven by the tissue immune environment, as evidenced by BM Mks having an MkL-like phenotype under the influence of pathogen receptor challenge and lung-associated immune molecules, such as IL-33. Our in vitro and in vivo assays demonstrated that MkL internalized and processed both antigenic proteins and bacterial pathogens. Furthermore, MkL induced CD4+ T cell activation in an MHC II–dependent manner both in vitro and in vivo. These data indicated that MkL had key immune regulatory roles dictated in part by the tissue environment.pre-print236 K
Microsurgical and tractographic anatomical study of insular and transsylvian transinsular approach
This study is to define the operative anatomy of the insula with emphasis on the transsylvian transinsular approach. The anatomy was studied in 15 brain specimens, among five were dissected by use of fiber dissection technique; diffusion tensor imaging of 10 healthy volunteers was obtained with a 1.5-T MR system. The temporal stem consists mainly of the uncinate fasciculus, inferior occipitofrontal fasciculus, Meyer’s loop of the optic radiation and anterior commissure. The transinsular approach requires an incision of the inferior limiting sulcus. In this procedure, the fibers of the temporal stem can be interrupted to various degrees. The fiber dissection technique is a very relevant and reliable method for neurosurgeons to study the details of brain anatomic features. The DTI fiber tracking technique can identify the fiber tracts of the temporal stem. Moreover, it will also help further functional study of human insula
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Clash of pans: pan-Africanism and pan-Anglo-Saxonism and the global colour line, 1919–1945
The article demonstrates both conceptually and empirically that pan-Anglo-Saxonist knowledge networks reconstructed and reimagined an apparently de-racialised, scientific, sober and liberal world order that outwardly abandoned, but did not eradicate the twin phenomena of racism and imperialism. Rather the new liberal (imperial) internationalists, organised in newly formed “think tanks” such as Chatham House and the Council on Foreign Relations, and through their increasingly global elite networks, mounted a top-down battle for minds at home and in the wider world. Operating in state-private elite networks, they drove the movement to manage change and develop a new liberal world order particularly to contain pan-Africanists who combatted the domination and exploitation of Africans worldwide. More broadly, we indicate that the pragmatic response to the extremes of Nazi ideology and a countering movement from the cadres of Asian, African and African American intellectuals, anti-colonial and anti-racist struggles within the national and global context, forced the Anglo-centric elites to promote change, albeit limited
Psychological illness is commonly associated with functional gastrointestinal disorders and is important to consider during patient consultation: a population-based study
BACKGROUND: Some individuals with functional gastrointestinal disorders (FGID) suffer long-lasting symptoms without ever consulting their doctors. Our aim was to study co-morbidity and lifestyle differences among consulters and non-consulters with persistent FGID and controls in a defined adult population. METHODS: A random sample of the general adult Swedish population was obtained by a postal questionnaire. The Abdominal Symptom Questionnaire (ASQ) was used to measure GI symptomatology and grade of GI symptom severity and the Complaint Score Questionnaire (CSQ) was used to measure general symptoms. Subjects were then grouped for study by their symptomatic profiles. Subjects with long-standing FGID (n = 141) and subjects strictly free from gastrointestinal (GI) symptoms (n = 97) were invited to attend their local health centers for further assessment. RESULTS: Subjects with FGID have a higher risk of psychological illness [OR 8.4, CI(95)(4.0–17.5)] than somatic illness [OR 2.8, CI(95)(1.3–5.7)] or ache and fatigue symptoms [OR 4.3, CI(95)(2.1–8.7)]. Subjects with psychological illness have a higher risk of severe GI symptoms than controls; moreover they have a greater chance of being consulters. Patients with FGID have more severe GI symptoms than non-patients. CONCLUSION: There is a strong relation between extra-intestinal, mental and somatic complaints and FGID in both patients and non-patients. Psychological illness increases the chance of concomitantly having more severe GI symptoms, which also enhance consultation behaviour
Abuse in Women and Men with and without Functional Gastrointestinal Disorders
We aimed to investigate the history of abuse in childhood and adulthood and health-related quality of life (HRQL) in women and men with FGID in the general adult population. A cross-sectional study in a random population sample (n = 1,537, 20–87 years) living in Östhammar municipality, Sweden, in 1995 was performed. Persons with FGID (n = 141) and a group of abdominal symptom-free controls (SSF, n = 97) were selected by means of a validated questionnaire assessing gastrointestinal symptoms (the ASQ). Abuse, anxiety and depression (the HADS) and HRQL (the PGWB) were measured. Women with FGID had a higher risk of having a history of some kind of abuse, as compared with the SSF controls (45% vs.16%, OR = 2.0, 95% CI: 1.01–3.9; SSF = 1), in contrast to men (29% vs. 24% n.s.). Women with a history of abuse and FGID had reduced HRQL 91 (95% CI 85–97) as compared with women without abuse history 100 (95% CI 96–104, P = 0.01, “healthy” = 102–105 on PGWB). Childhood emotional abuse was a predictor for consulting with OR = 4.20 (95% CI: 1.12–15.7.7). Thus, previous abuse is common in women with FGID and must be considered by the physician for diagnosis and treatment of the disorder
Human Auditory Cortical Activation during Self-Vocalization
During speaking, auditory feedback is used to adjust vocalizations. The brain systems mediating this integrative ability have been investigated using a wide range of experimental strategies. In this report we examined how vocalization alters speech-sound processing within auditory cortex by directly recording evoked responses to vocalizations and playback stimuli using intracranial electrodes implanted in neurosurgery patients. Several new findings resulted from these high-resolution invasive recordings in human subjects. Suppressive effects of vocalization were found to occur only within circumscribed areas of auditory cortex. In addition, at a smaller number of sites, the opposite pattern was seen; cortical responses were enhanced during vocalization. This increase in activity was reflected in high gamma power changes, but was not evident in the averaged evoked potential waveforms. These new findings support forward models for vocal control in which efference copies of premotor cortex activity modulate sub-regions of auditory cortex
Hemispheric Asymmetry in White Matter Connectivity of the Temporoparietal Junction with the Insula and Prefrontal Cortex
The temporoparietal junction (TPJ) is a key node in the brain's ventral attention network (VAN) that is involved in spatial awareness and detection of salient sensory stimuli, including pain. The anatomical basis of this network's right-lateralized organization is poorly understood. Here we used diffusion-weighted MRI and probabilistic tractography to compare the strength of white matter connections emanating from the right versus left TPJ to target regions in both hemispheres. Symmetry of structural connectivity was evaluated for connections between TPJ and target regions that are key cortical nodes in the right VAN (insula and inferior frontal gyrus) as well as target regions that are involved in salience and/or pain (putamen, cingulate cortex, thalamus). We found a rightward asymmetry in connectivity strength between the TPJ and insula in healthy human subjects who were scanned with two different sets of diffusion-weighted MRI acquisition parameters. This rightward asymmetry in TPJ-insula connectivity was stronger in females than in males. There was also a leftward asymmetry in connectivity strength between the TPJ and inferior frontal gyrus, consistent with previously described lateralization of language pathways. The rightward lateralization of the pathway between the TPJ and insula supports previous findings on the roles of these regions in stimulus-driven attention, sensory awareness, interoception and pain. The findings also have implications for our understanding of acute and chronic pains and stroke-induced spatial hemineglect
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