Damaged Intestinal Epithelial Integrity Linked to Microbial Translocation in Pathogenic Simian Immunodeficiency Virus Infections

The chronic phase of HIV infection is marked by pathological activation of the immune system, the extent of which better predicts disease progression than either plasma viral load or CD4+ T cell count. Recently, translocation of microbial products from the gastrointestinal tract has been proposed as an underlying cause of this immune activation, based on indirect evidence including the detection of microbial products and specific immune responses in the plasma of chronically HIV-infected humans or SIV-infected Asian macaques. We analyzed tissues from SIV-infected rhesus macaques (RMs) to provide direct in situ evidence for translocation of microbial constituents from the lumen of the intestine into the lamina propria and to draining and peripheral lymph nodes and liver, accompanied by local immune responses in affected tissues. In chronically SIV-infected RMs this translocation is associated with breakdown of the integrity of the epithelial barrier of the gastrointestinal (GI) tract and apparent inability of lamina propria macrophages to effectively phagocytose translocated microbial constituents. By contrast, in the chronic phase of SIV infection in sooty mangabeys, we found no evidence of epithelial barrier breakdown, no increased microbial translocation and no pathological immune activation. Because immune activation is characteristic of the chronic phase of progressive HIV/SIV infections, these findings suggest that increased microbial translocation from the GI tract, in excess of capacity to clear the translocated microbial constituents, helps drive pathological immune activation. Novel therapeutic approaches to inhibit microbial translocation and/or attenuate chronic immune activation in HIV-infected individuals may complement treatments aimed at direct suppression of viral replication

Benign follicular tumors

Benign follicular tumors comprise a large and heterogeneous group of neoplasms that share a common histogenesis and display morphological features resembling one or several portions of the normal hair follicle, or recapitulate part of its embryological development. Most cases present it as clinically nondescript single lesions and essentially of dermatological relevance. Occasionally, however, these lesions be multiple and represent a cutaneous marker of complex syndromes associated with an increased risk of visceral neoplasms. In this article, the authors present the microscopic structure of the normal hair follicle as a basis to understand the type and level of differentiation of the various follicular tumors. The main clinicopathological features and differential diagnosis of benign follicular tumors are then discussed, including dilated pore of Winer, pilar sheath acanthoma, trichoadenoma, trichilemmoma, infundibuloma, proliferating trichilemmal cyst/tumor, trichoblastoma and its variants, pilomatricoma, trichodiscoma/fibrofolliculoma, neurofollicular hamartoma and trichofolliculoma. In addition, the main syndromes presenting with multiple follicular tumors are also discussed, namely Cowden, Birt-Hogg-Dubé, Rombo and Bazex-Dupré-Christol syndromes, as well as multiple tumors of follicular infundibulum (infundibulomatosis) and multiple trichoepitheliomas. Although the diagnosis of follicular tumors relies on histological examination, we highlight the importance of their knowledge for the clinician, especially when in presence of patients with multiple lesions that may be the cutaneous marker of a cancer-prone syndrome. The dermatologist is therefore in a privileged position to recognize these lesions, which is extremely important to provide further propedeutic, appropriate referral and genetic counseling for these patients.info:eu-repo/semantics/publishedVersio

Nicotinic receptors

Regulation of normal or abnormal behaviour is critically controlled by the central serotonergic systems. Recent evidence has suggested that serotonin (5-HT) neurotransmission dysfunction contributes to a variety of pathological conditions, including depression, anxiety, schizophrenia and Parkinson’s disorders. There is also a great amount of evidence indicating that 5-HT signalling may affect the reinforcing properties of drugs of abuse by the interaction and modulation of dopamine (DA) function. This chapter is focused on one of the more addictive drugs, nicotine. It is widely recognised that the effects of nicotine are strongly associated with the stimulatory action it exhibits on mesolimbic DAergic function. We outline the role of 5-HT and its plethora of receptors, focusing on 5-HT2 subtypes with relation to their involvement in the neurobiology of nicotine addiction. We also explore the novel pharmacological approaches using 5-HT agents for the treatment of nicotine dependence. Compelling evidence shows that 5-HT2C receptor agonists may be possible therapeutic targets for smoking cessation, although further investigation is required.peer-reviewe

A metabolomics investigation into the effects of HIV protease inhibitors on HPV16 E6 expressing cervical carcinoma cells

Recently, it has been reported that anti-viral drugs, such as indinavir and lopinavir (originally targeted for HIV), also inhibit E6-mediated proteasomal degradation of mutant p53 in E6-transfected C33A cells. In order to understand more about the mode-of-action(s) of these drugs the metabolome of HPV16 E6 expressing cervical carcinoma cell lines was investigated using mass spectrometry (MS)-based metabolic profiling. The metabolite profiling of C33A parent and E6-transfected cells exposed to these two antiviral drugs was performed by ultra performance liquid chromatography (UPLC)-MS and gas chromatography (GC)-time of flight (TOF)-MS. Using a combination of univariate and multivariate analyses, these metabolic profiles were investigated for analytical and biological reproducibility and to discover key metabolite differences elicited during anti-viral drug challenge. This approach revealed both distinct and common effects of these two drugs on the metabolome of two different cell lines. Finally, intracellular drug levels were quantified, which suggested in the case of lopinavir that increased activity of membrane transporters may contribute to the drug sensitivity of HPV infected cells