Role of macrophage sialoadhesin in host defense against the sialylated pathogen group B <em>Streptococcus</em>

ABSTRACT: Several bacterial pathogens decorate their surfaces with sialic acid (Sia) residues within cell wall components or capsular exopolysaccharides. Sialic acid expression can promote bacterial virulence by blocking complement activation or by engagement of inhibitory sialic acid-binding immunoglobulin-like lectins (Siglecs) on host leukocytes. Expressed at high levels on splenic and lymph node macrophages, sialoadhesin (Sn) is a unique Siglec with an elongated structure that lacks intracellular signaling motifs. Sialoadhesin allows macrophage to engage certain sialylated pathogens and stimulate inflammatory responses, but the in vivo significance of sialoadhesin in infection has not been shown. We demonstrate that macrophages phagocytose the sialylated pathogen group B Streptococcus (GBS) and increase bactericidal activity via sialoadhesin-sialic-acid-mediated recognition. Sialoadhesin expression on marginal zone metallophillic macrophages in the spleen trapped circulating GBS and restricted the spread of the GBS to distant organs, reducing mortality. Specific IgM antibody responses to GBS challenge were also impaired in sialoadhesin-deficient mice. Thus, sialoadhesin represents a key bridge to orchestrate innate and adaptive immune defenses against invasive sialylated bacterial pathogens. KEY MESSAGE: Sialoadhesin is critical for macrophages to phagocytose and clear GBS. Increased GBS organ dissemination in the sialoadhesin-deficient mice. Reduced anti-GBS IgM production in the sialoadhesin-deficient mice. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00109-014-1157-y) contains supplementary material, which is available to authorized users

Highly polymorphic microsatellite markers for the assessment of male reproductive skew and genetic variation in Critically Endangered crested macaques (Macaca nigra)

Genetic analyses based on non-invasively collected samples have become an important tool for evolutionary biology and conservation. Crested macaques (Macaca nigra), endemic to Sulawesi, Indonesia, are important for our understanding of primate evolution as Sulawesi macaques represent an exceptional example of primate adaptive radiation. Crested macaques are also Critically Endangered. However, to date we know very little about their genetics. The aim of our study was to find and validate microsatellite markers useful for evolutionary, conservation and other genetic studies on wild crested macaques. Using faecal samples of 176 wild macaques living in the Tangkoko Reserve, Sulawesi, we identified 12 polymorphic microsatellite loci through cross-species PCR amplification with later modification of some of these primers. We tested their suitability by investigating and exploring patterns of paternity, observed heterozygosity and evidence for inbreeding. We assigned paternity to 63 of 65 infants with high confidence. Among cases with solved paternity, we found no evidence of extra-group paternity and natal breeding. We found a relatively steep male reproductive skew B index of 0.330±0.267; mean±SD) and mean alpha paternity of 65% per year with large variation across groups and years (29-100%). Finally, we detected an excess in observed heterozygosity and no evidence of inbreeding across our three study groups, with an observed heterozygosity of 0.766±0.059 and expected heterozygosity of 0.708±0.059, and an inbreeding coefficient of -0.082±0.035. Our results indicate that the selected markers are useful for genetic studies on wild crested macaques, and possible also other Sulawesi and closely related macaques. They further suggest that the Tangkoko population of crested macaques is still genetically variable despite its small size, isolation and the species’ reproductive patterns. This gives us hope that other endangered primate species living in small, isolated populations may also retain a healthy gene pool, at least in the short term

CLINICAL PROFILE, PRESCRIPTION PATTERNS, AND ADVERSE DRUG REACTIONS IN PATIENTS WITH VITILIGO: A PROSPECTIVE STUDY

Objectives: The objectives of the study were to assess clinical profile (age of onset, age of presentation, gender, site of involvement, severity (stage), type of vitiligo, triggering factors, and associated diseases), prescription patterns (monotherapy, combination therapy, oral, topical, and therapeutic categories of drugs prescribed) and to monitor and report adverse drug reactions (based on World Health Organization [WHO] causality assessment scale) in vitiligo patients. Methods: A hospital-based prospective observational study was carried out by evaluating and assessing the clinical profile and prescription patterns of 85 patients who attended dermatology venereology and leprosy (DVL) outpatient department at Sri Padmavathi Medical College for Women, SVIMS, Tirupati, over a period of 6 months from June 2019 to December 2019. Results: In our study, forty four (51.77%) patients were female, vitiligo vulgaris is the most common morphological type observed in twenty seven (31.76%) patients. 31–50 years was the predominant age group. The mean age of onset and presentation was 38.35 (standard deviation of 18.37) and 43.27 (standard deviation of 17.96) years, respectively. Forty-one (48.23%) patients were having Stage 1 vitiligo. Fifty (58.85%) patients were having vitiligo at more than 1 site. Twelve (14.11%) patients were having a positive family history of vitiligo. Thirty-seven (43.53%) patients had triggering factors. Associated diseases were found in thirty (35%) patients. Combination therapy was given to sixty one (71.77%) patients. Topical medications were given to fifty two (61.18%) patients. During the study, we did not have a single patient complaining of any adverse drug reaction. Conclusion: Longer the time after appearance of vitiligo, lesser the number of patients attending follow-up. If vitiligo is diagnosed at the earliest stage, more are the chances for complete repigmentation. Patients with a poor economic background are less bothered about their skin condition and are not using medications properly

Hick and Radhakrishnan on Religious Diversity: Back to the Kantian Noumenon

We shall examine some conceptual tensions in Hick’s ‘pluralism’ in the light of S. Radhakrishnan’s reformulation of classical Advaita. Hick himself often quoted Radhakrishnan’s translations from the Hindu scriptures in support of his own claims about divine ineffability, transformative experience and religious pluralism. However, while Hick developed these themes partly through an adaptation of Kantian epistemology, Radhakrishnan derived them ultimately from Śaṁkara (c.800 CE), and these two distinctive points of origin lead to somewhat different types of reconstruction of the diversity of world religions. Our argument will highlight the point that Radhakrishnan is not a ‘pluralist’ in terms of Hick’s understanding of the Real. The Advaitin ultimate, while it too like Hick’s Real cannot be encapsulated by human categories, is, however, not strongly ineffable, because some substantive descriptions, according to the Advaitic tradition, are more accurate than others. Our comparative analysis will reveal that they differ because they are located in two somewhat divergent metaphysical schemes. In turn, we will be able to revisit, through this dialogue between Hick and Radhakrishnan, the intensely vexed question of whether Hick’s version of pluralism is in fact a form of covert exclusivism.This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/s11841-015-0459-

Hampered Foraging and Migratory Performance in Swans Infected with Low-Pathogenic Avian Influenza A Virus

It is increasingly acknowledged that migratory birds, notably waterfowl, play a critical role in the maintenance and spread of influenza A viruses. In order to elucidate the epidemiology of influenza A viruses in their natural hosts, a better understanding of the pathological effects in these hosts is required. Here we report on the feeding and migratory performance of wild migratory Bewick's swans (Cygnus columbianus bewickii Yarrell) naturally infected with low-pathogenic avian influenza (LPAI) A viruses of subtypes H6N2 and H6N8. Using information on geolocation data collected from Global Positioning Systems fitted to neck-collars, we show that infected swans experienced delayed migration, leaving their wintering site more than a month after uninfected animals. This was correlated with infected birds travelling shorter distances and fuelling and feeding at reduced rates. The data suggest that LPAI virus infections in wild migratory birds may have higher clinical and ecological impacts than previously recognised

Understanding How Social Entrepreneurs Fit into the Tourism Discourse

This chapter discusses how social entrepreneurs fit into the existing tourism discourse. It examines four areas of literature in particular, tourism entrepreneurs, sustainability, destination development and intrapreneurship, and analyzes how introducing the concept of social entrepreneurs into these discussions is useful, and contributes to our understanding. Furthermore the paper illustrates that as social entrepreneurs are relevant to a broad range of issues in the tourism literature this should prevent the development of research silos where social entrepreneurship scholars seek out their own vein of research. The nexus of common ground and interests, as displayed in this chapter, should enhance the development of research, thought and understanding of social entrepreneurs within the field as a whole The key argument is that research on social entrepreneurs is not just relevant for those interested in entrepreneurs it also effects our thinking on issues such as destination development, relationships between stakeholders, tourism policy and sustainability. The chapter concludes with a wide range of questions for further research

Transthoracic coronary flow reserve and dobutamine derived myocardial function: a 6-month evaluation after successful coronary angioplasty

After percutaneous transluminal coronary angioplasty (PTCA), stress-echocardiography and gated single photon emission computerized tomography (g-SPECT) are usually performed but both tools have technical limitations. The present study evaluated results of PTCA of left anterior descending artery (LAD) six months after PTCA, by combining transthoracic Doppler coronary flow reserve (CFR) and color Tissue Doppler (C-TD) dobutamine stress. Six months after PTCA of LAD, 24 men, free of angiographic evidence of restenosis, underwent standard Doppler-echocardiography, transthoracic CFR of distal LAD (hyperemic to basal diastolic coronary flow ratio) and C-TD at rest and during dobutamine stress to quantify myocardial systolic (S(m)) and diastolic (E(m )and A(m), E(m)/A(m )ratio) peak velocities in middle posterior septum. Patients with myocardial infarction, coronary stenosis of non-LAD territory and heart failure were excluded. According to dipyridamole g-SPECT, 13 patients had normal perfusion and 11 with perfusion defects. The 2 groups were comparable for age, wall motion score index (WMSI) and C-TD at rest. However, patients with perfusion defects had lower CFR (2.11 ± 0.4 versus 2.87 ± 0.6, p < 0.002) and septal S(m )at high-dose dobutamine (p < 0.01), with higher WMSI (p < 0.05) and stress-echo positivity of LAD territory in 5/11 patients. In the overall population, CFR was related negatively to high-dobutamine WMSI (r = -0.50, p < 0.01) and positively to high-dobutamine S(m )of middle septum (r = 0.55, p < 0.005). In conclusion, even in absence of epicardial coronary restenosis, stress perfusion imaging reflects a physiologic impairment in coronary microcirculation function whose magnitude is associated with the degree of regional functional impairment detectable by C-TD

Non-Linear Population Firing Rates and Voltage Sensitive Dye Signals in Visual Areas 17 and 18 to Short Duration Stimuli

Visual stimuli of short duration seem to persist longer after the stimulus offset than stimuli of longer duration. This visual persistence must have a physiological explanation. In ferrets exposed to stimuli of different durations we measured the relative changes in the membrane potentials with a voltage sensitive dye and the action potentials of populations of neurons in the upper layers of areas 17 and 18. For durations less than 100 ms, the timing and amplitude of the firing and membrane potentials showed several non-linear effects. The ON response became truncated, the OFF response progressively reduced, and the timing of the OFF responses progressively delayed the shorter the stimulus duration. The offset of the stimulus elicited a sudden and strong negativity in the time derivative of the dye signal. All these non-linearities could be explained by the stimulus offset inducing a sudden inhibition in layers II–III as indicated by the strongly negative time derivative of the dye signal. Despite the non-linear behavior of the layer II–III neurons the sum of the action potentials, integrated from the peak of the ON response to the peak of the OFF response, was almost linearly related to the stimulus duration