844 research outputs found

    Immunopathology of Leishmaniasis: an update.

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    Leishmaniasis represents a severe, increasing, public health problem. The perspective of its control is highly dependent on research progress, on therapeutic manipulations of the immune system, and on vaccine development. There is a correlation between the clinical outcome of Leishmania infection and the cytokine response profile. While a protective immune response against Leishmania has been clearly identified to be related to the influence of a type-1 response and IFN-gamma production, the precise role of T helper (TH) 2 cytokines in non-healing infections requires further exploration. IL-4 and IL-13 (TH2 cytokines) can promote disease progression in cutaneous leishmaniasis, whereas IL-4 would appear to enhance protective type-1 responses in visceral leishmaniasis. Thus, the TH1/TH2 paradigm of resistance/susceptibility to intracellular parasites is probably an oversimplification of a more complicated network of regulatory/counter regulatory interactions. Moreover, the presence of antigen specific regulatory T cell subsets may provide an environment that contributes to the balance between TH1 and TH2 cells. Finally, the involvement of CD8 positive T cells has been described, but the modality of their function in this kind of infection has not been so far elucidated

    Immunology of human rickettsial diseases.

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    Among human rickettsial diseases caused by micro-organisms of the genus Rickettsia (Order Rickettsiales; Family Rickettsiaceae), transmitted to human hosts through arthropod vectors, Mediterranean Spotted Fever, or Boutonneuse Fever, and Rocky Mountain Spotted Fever are considered to be important infectious diseases due to continued prevalence in the developed world, and potentially fatal outcome in severe cases. Proliferation of rickettsiae, at the site of the tick bite, results in focal epidermal and dermal necrosis (tache noire). Rickettsiae then spread via lymphatic vessels to the regional lymph nodes, and, via the bloodstream, to skin, brain, lungs, heart, liver, spleen and kidneys. The pathogen invades and proliferates in the endothelial cells of small vessels, target cells of rickettsial infection, destroying them, and spreading the infection to the endothelia of the vascular tree. The damage of the endothelium, and the subsequent endothelia dysfunction, is followed by the activation of acute phase responses, with alteration in the coagulation and in the cytokine network, together with a transient immune dysregulation, characterized by the reduction in peripheral CD4+ T lymphocytes

    Strategies and Controversies in the Treatment With Carbon Dioxide Laser of Laryngeal Hemangioma: A Case Series and Review of the Literature

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    Introduction: The hemangioma is the most common vascular tumor, involving the head and neck in 60% of cases. It is rare in the larynx. In children, hemangiomas are more frequent on the subglottis, whereas in adults the most common site is the supraglottis. Laryngeal hemangioma with cavernous features isolated to the free edge of the vocal fold is a very rare clinical finding. We present 2 cases of glottic hemangioma. Both patients reported severe hoarseness. Cases: In the first patient, an extensive blue-purple mass was seen on the right vocal cord. The patient was posted for microlaryngeal surgery with carbon dioxide (CO2) laser. Second patient had a large, smooth, flesh-colored polypoid mass emanating from the left vocal cord. The patient was posted for microlaryngeal surgery. After 2 months, both patients showed a considerable voice improvement. Discussion: Vocal cord hemangiomas are very rare, and they usually cause problem in the voice of the patient. A vascular lesion that may mimic a hemangioma may sometimes result from an organizing hematoma following a hemorrhage on the vocal cords due to voice abuse. Laryngeal hemangiomas also need to be distinguished pathologically from polypoidal vascular granulation tissue that may be produced by laryngeal biopsy, intubation, or trauma. Indirect endoscopy is enough to diagnosis. No active treatment is advised for adult laryngeal hemangiomas unless the lesions are symptomatic or show a tendency to involve other parts. There is no uniformly accepted treatment of head and neck hemangiomas. Surgical excision with laser CO2 microlaryngoscopic techniques gives satisfactory results

    Fear of missing out (FoMO) and internet use: A comprehensive systematic review and meta-analysis.

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    FoMO has been considered a predisposing factor toward excessive internet use, and a great deal of literature has investigated the link between FoMO and internet use. However, there is still a lack of cohesion in the literature. The current study have been conducted and reported in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). In the current systematic review and meta-analysis of 86 effect-sizes, representative of 55,134 participants (Mean age = 22.07, SD = 6.15, females = 58.37%), we found that the strength of the trait FoMO- internet use association significantly varies from r = 0.11 to r = 0.63. In some populations, FoMO appears to increase with age and it is reverse in other populations. Facebook use was unrelated to FoMO in some populations, and higher FoMO was linked with stopping Instagram use for some individuals. The FoMO- internet use association was independent of their severity, as the interaction was not significant, and this association was neither linear nor curvilinear. The FoMO-internet use association does not appear to be associated with depressive, anxiety, and stress symptoms or level of life satisfaction. The COVID-19 pandemic was the only significant moderator of the FoMO-internet use association, strengthening this relationship. FoMO demonstrates a considerable role in internet use; however, there is no evidence of interaction or bi-directional association between the mentioned. Overall, we still don't know what factors contribute to individuals exhibiting distinct patterns in the FoMO-internet use association

    Pulmonary arterial hypertension (PAH) from autopsy study: T-cells, B-cells and mastocytes detection as morphological evidence of immunologically mediated pathogenesis.

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    Background: Pulmonary arterial hypertension (PAH) is characterized by severe vascular remodelling, resulting in increased pulmonary vascular resistance with cardiac hypertrophy and heart failure. However, the diagnosis of PAH is often inaccurate. Many cases of PAH are incorrectly diagnosed or missed, and they are often associated with death. The aim of this study was to verify the morphological and histological criteria of fatal cases of PAH and evaluate the lymphocytic populations associated to lesions with reactive neo-angiogenesis. Methods: Pulmonary lung sections from 10 cases of sudden unexpected death (SUD) in the absence of previously diagnosed diseases and in an apparent state of well-being, with final histological post autopsy diagnosis of PAH were collected. The pathological findings were compared using ten controls from non-pathological lung from deaths from other causes. The autopsies included 4 males (40%) and 6 females (60%) with an average age of 52.1 ± 10.1 years. Sections stained with hematoxylin and eosin (H&E) were revised for a morphological diagnosis. Subsequently, serial sections were performed and stained with immunohistochemistry for anti-CD20 (B-lymphocytes), anti-CD3 (T-lymphocytes), anti-CD4 (T-helper lumphocytes), anti-CD8 (T-cytotoxic lymphocytes) and anti-CD117/C-Kit (mast cells/MCs) to detect inflammatory infiltrate and different ratios of cell-type. Statistical analysis was conducted using a paired t-test looking at 100 cells in 3 different tissue samples representative of vascular lesion and 3 different random normal lung parenchyma fields without lesion (from 10 normal control lungs), to identify specific lymphocyte subpopulations in inflammatory infiltrates. Results: There was a significant percentage increase of CD20 (p < 0.001), CD8 (p = 0.002), CD4 (p < 0.001), and CD117/C-Kit positive (C-Kit+; p < 0.001) cells mainly detected around wall vessels; while increased MCs positivity and C-Kit+ were observed especially in alveolar septa. In addition, reactive angiomatosis was observed. Conclusions: The inflammatory infiltrate should be included for a correct diagnosis of PAH besides the vascular remodelling. The inflammatory infiltrate seems to be implicated as a main factor in the pathogenesis. This finding is important to rule out secondary pulmonary hypertension, to identify SUDs of unknown causes and to add new elements to the literature that can explain the immunologically related pathogenesis of PAH

    Isolation and characterization of Bartonella quintana from parotid gland of an immunocompetent man.

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    We describe a case of the isolation of Bartonella quintana from the parotid gland of an apparently healthy man. Pathological examination showed intraparotid granulomatous abscessual lymphadenitis. Diagnosis was made on the basis of high titers of immunoglobulin G (IgG) and IgM antibodies and of culture isolation of a causative agent from parotid aspirate
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