L-selectin expression is regulated by CXCL8-induced reactive oxygen species produced during human neutrophil rolling.

Neutrophils destroy invading microorganisms by phagocytosis by bringing them into contact with bactericidal substances, among which ROS are the most important. However, ROS also function as important physiological regulators of cellular signaling pathways. Here, we addressed the involvement of oxygen derivatives in the regulation of human neutrophil rolling, an essential component of the inflammatory response. Flow experiments using dihydroethidium-preloaded human neutrophils showed that these cells initiate an early production of intracellular ROS during the rolling phase of the adhesion cascade, a phenomenon that required cell rolling, and the interaction of the chemokine receptor CXCR2 with their ligand CXCL8. Flow cytometry experiments demonstrated that L-selectin shedding in neutrophils is triggered by ROS through an autocrine-paracrine mechanism. Preincubation of neutrophils with the NADPH oxidase complex inhibitor diphenyleniodonium chloride significantly increased the number of rolling neutrophils on endothelial cells. Interestingly, the same effect was observed when CXCL8 signaling was interfered using either a blocking monoclonal antibody or an inhibitor of its receptor. These findings indicate that, in response to CXCL8, neutrophils initiate ROS production during the rolling phase of the inflammatory response. This very early ROS production might participate in the modulation of the inflammatory response by inducing L-selectin shedding in neutrophils.

[Effects of prebiotics and probiotics on gastrointestinal tract lymphoid tissue in hiv infected patients]. / Efecto de la terapia con probióticos/prebióticos sobre la reconstitución del tejido linfoide asociado a la mucosa gastrointestinal durante la infección por el virus de la inmunodeficiencia humana-1.

HIV infection induces alterations in almost all immune cell populations, mainly in CD4+ T cells, leading to the development of opportunistic infections. The gut-associated lymphoid tissue (GALT) constitutes the most important site for viral replication, because the main target cells, memory T-cells, reside in this tissue. It is currently known that alterations in GALT are critical during the course of the infection, as HIV-1 induces loss of tissue integrity and promotes translocation of microbial products from the intestinal lumen to the systemic circulation, leading to a persistent immune activation state and immune exhaustion. Although antiretroviral treatment decreases viral load and substantially improves the prognosis of the infection, the alterations in GALT remains, having a great impact on the ability to establish effective immune responses. This emphasizes the importance of developing new therapeutic alternatives that may promote structural and functional integrity of this tissue. In this regard, therapy with probiotics/prebiotics has beneficial effects in GALT, mainly in syndromes characterized by intestinal dysbiosis, including the HIV-1 infection. In these patients, the consumption of probiotics/prebiotics decreased microbial products in plasma and CD4+ T cell activation, increased CD4+ T cell frequency, in particular Th17, and improved the intestinal flora. In this review, the most important findings on the potential impact of the probiotics/prebiotics therapy are discussed.

Prevention of neutrophil extravasation by α2-adrenoceptor-mediated endothelial stabilization.

Adrenergic receptors are expressed on the surface of inflammation-mediating cells, but their potential role in the regulation of the inflammatory response is still poorly understood. The objectives of this work were to study the effects of α2-adrenergic agonists on the inflammatory response in vivo and to determine their mechanism of action. In two mouse models of inflammation, zymosan air pouch and thioglycolate-induced peritonitis models, the i.m. treatment with xylazine or UK14304, two α2-adrenergic agonists, reduced neutrophil migration by 60%. The α2-adrenergic antagonist RX821002 abrogated this effect. In flow cytometry experiments, the basal surface expression of L-selectin and CD11b was modified neither in murine nor in human neutrophils upon α2-agonist treatment. Similar experiments in HUVEC showed that UK14304 prevented the activation-dependent upregulation of ICAM-1. In contrast, UK14304 augmented electrical resistance and reduced macromolecular transport through a confluent HUVEC monolayer. In flow chamber experiments, under postcapillary venule-like flow conditions, the pretreatment of HUVECs, but not neutrophils, with α2-agonists decreased transendothelial migration, without affecting neutrophil rolling. Interestingly, α2-agonists prevented the TNF-α-mediated decrease in expression of the adherens junctional molecules, VE-cadherin, ß-catenin, and plakoglobin, and reduced the ICAM-1-mediated phosphorylation of VE-cadherin by immunofluorescence and confocal analysis and Western blot analysis, respectively. These findings indicate that α2-adrenoceptors trigger signals that protect the integrity of endothelial adherens junctions during the inflammatory response, thus pointing at the vascular endothelium as a therapeutic target for the management of inflammatory processes in humans.

In vivo modulation of the inflammatory response by nonsteroidal antiinflammatory drug-related compounds that trigger L-selectin shedding.

Diphenylamine-based nonsteroidal antiinflammatory drugs (NSAIDs) are able to cause in vitro the shedding of L-selectin. The aim of this work was to determine the physio-logic relevance of L-selectin shedding in the antiinflammatory effect exerted by NSAIDs in vivo. Chemical compounds structurally related to NSAIDs - including diphenyl-amine, N-phenylanthranilic acid (N-Ph), diphenylacetic acid - as well as the traditional NSAID indomethacin were studied using the zymosan air-pouch mouse model. Animals intramuscularly pretreated with indomethacin or N-Ph, but not with diphenyl-amine or diphenylacetic acid, showed a significant dose-dependent reduction in the number of neutrophils compared with untreated animals (N-Ph, IC50 = 6.7 mg/kg). Except for indomethacin, none of these compounds caused any significant reduction in cyclooxygenase-1 activity in vivo. In flow chamber experiments, N-Ph reduced the capability of human neutrophils to pass across the endothelial barrier by interfering with leukocyte rolling step on HUVEC. N-Ph, but not diphenylacetic acid, induced activation-independent L-selectin shedding in mouse neutrophils. Interestingly, N-Ph exerted an antiinflammatory effect similar to that of the anti-L-selectin blocking antibody Mel-14, although no additive action was observed when both compounds were combined. These data suggest that the L-selectin shedding induced by NSAIDs may be involved in the antiinflammatory action exerted by these compounds in clinical settings.

Facial disability index (FDI): adaptation to Spanish, reliability and validity.

OBJECTIVES: To adapt to Spanish the facial disability index (FDI) described by VanSwearingen and Brach in 1995 and to assess its reliability and validity in patients with facial nerve paresis after parotidectomy. STUDY DESIGN: The present study was conducted in two different stages: a) cross-cultural adaptation of the questionnaire and b) cross-sectional study of a control group of 79 Spanish-speaking patients who suffered facial paresis after superficial parotidectomy with facial nerve preservation. The cross-cultural adaptation process comprised the following stages: (I) initial translation, (II) synthesis of the translated document, (III) retro-translation, (IV) review by a board of experts, (V) pilot study of the pre-final draft and (VI) analysis of the pilot study and final draft. RESULTS: The reliability and internal consistency of every one of the rating scales included in the FDI (Cronbach's alpha coefficient) was 0.83 for the complete scale and 0.77 and 0.82 for the physical and the social well-being subscales. The analysis of the factorial validity of the main components of the adapted FDI yielded similar results to the original questionnaire. Bivariate correlations between FDI and House-Brackmann scale were positive. The variance percentage was calculated for all FDI components. CONCLUSIONS: The FDI questionnaire is a specific instrument for assessing facial neuromuscular dysfunction which becomes a useful tool in order to determine quality of life in patients with facial nerve paralysis. Spanish adapted FDI is equivalent to the original questionnaire and shows similar reliability and validity. The proven reproducibility, reliability and validity of this questionnaire make it a useful additional tool for evaluating the impact of facial nerve paralysis in Spanish-speaking patients.

Pro-Inflammatory Alterations of Circulating Monocytes in Latent Tuberculosis Infection.

Background: Latent tuberculosis infection (LTBI) has been associated with increased cardiovascular risk. We investigated the activation and pro-inflammatory profile of monocytes in individuals with LTBI and their association with coronary artery disease (CAD). Methods: Individuals 40-70 years old in Lima, Peru, underwent QuantiFERON-TB testing to define LTBI, completed a coronary computed tomography angiography to evaluate CAD, and provided blood for monocyte profiling using flow cytometry. Cells were stimulated with lipopolysaccharide to assess interleukin-6 (IL-6) and tumor necrosis factor (TNF)-α responses. Results: The clinical characteristics of the LTBI (n = 28) and non-LTBI (n = 41) groups were similar. All monocyte subsets from LTBI individuals exhibited higher mean fluorescence intensity (MFI) of CX3CR1 and CD36 compared with non-LTBI individuals. LTBI individuals had an increased proportion of nonclassical monocytes expressing IL-6 (44.9 vs 26.9; P = .014), TNF-α (62.3 vs 35.1; P = .014), and TNF-α+IL-6+ (43.2 vs 36.6; P = .042). Among LTBI individuals, CAD was associated with lower CX3CR1 MFI on classical monocytes and lower CD36 MFI across all monocyte subsets. In multivariable analyses, lower CD36 MFI on total monocytes (b = -0.17; P = .002) and all subsets remained independently associated with CAD in LTBI. Conclusions: Individuals with LTBI have distinct monocyte alterations suggestive of an exacerbated inflammatory response and tissue migration. Whether these alterations contribute to cardiovascular disease pathogenesis warrants further investigation.

A Sex-Stratified Analysis of Monocyte Phenotypes Associated with HIV Infection in Uganda.

Women with HIV may experience higher rates of non-AIDS comorbidities compared to men with HIV, but the underlying mechanisms are not well understood. We investigated sex-related differences in the effects of HIV on monocyte phenotypes within the Ugandan Study of HIV effects on the Myocardium and Atherosclerosis (mUTIMA). Of 133 participants who provided blood for flow cytometry assays, 86 (65%) were women and 91 (68%) were persons living with HIV (PLWH) on antiretroviral therapy. The median age was 57 (interquartile range, 52-63) years. PLWH exhibited a lower proportion of circulating CD14+CD16- classical monocytes (66.3% vs. 75.1%; p < 0.001), and higher proportion of CD14+CD16+ inflammatory monocytes (17% vs. 11.7%; p = 0.005) compared to HIV-uninfected participants. PLWH had an increased expression of the chemokine receptor CX3CR1 in total monocytes (CX3CR1+ monocytes, 24.5% vs. 4.7%; p < 0.001) and monocyte subsets. These findings were generally similar when analyzed by sex, with no significant interactions between sex and HIV status in adjusted models. Our data show that the inflammatory monocyte subset is expanded and monocyte CX3CR1 chemokine receptor expression is enhanced among PLWH, regardless of sex. Whether these parameters differentially affect risk for non-AIDS comorbidities and clinical outcomes in women with HIV requires additional investigation.

Induction of Follicular-Like CXCR5+ CD8+ T Cells by TGF-ß1/IL-23 Is Limited During HIV Infection.

Follicular CD4+ T cells are the main HIV reservoirs due to, among other factors, the low frequency of CD8+ T cells in lymphoid follicles. Follicular CXCR5+ CD8+ T cells are associated with HIV control, but their differentiation conditions are yet undefined. In this study, we explored the in vitro effect of transforming growth factor (TGF)-ß1, interleukin (IL)-12, and IL-23 on the induction of CXCR5, the follicle homing receptor, in human circulating CD8+ T cells from seronegative, and treated HIV-infected individuals. The combination of TGF-ß1 plus IL-23 induced the highest expression of CXCR5 in purified CD8+ T cells. These CXCR5+ CD8+ T cells also expressed a transcriptional and phenotypic profile similar to that of follicular CD4+ T cells, such as the upregulation of BCL6, inducible costimulator and CD40L, and downregulation of PRDM1. These cells responded in vitro to CXCL13 and had low expression of CCR7. In addition, after polyclonal stimulation, they produced IL-21, interferon-γ, and de novo perforin. However, in comparison with seronegative individuals, CD8+ T cells from HIV-infected patients had a lower response to TGF-ß1/IL-23, a defect that was restored with the blockade of the programmed cell death 1 inhibitory receptor. Thus, TGF-ß1 plus IL-23 induce follicular-like CXCR5+ CD8+ T cells in seronegative individuals, but in HIV-infected patients there is a limited response which could impair the generation of this cell population.

The Spontaneous Control of HIV Replication is Characterized by Decreased Pathological Changes in the Gut-associated Lymphoid Tissue.

BACKGROUND: HIV infection induces alterations in the gut-associated lymphoid tissue (GALT) that constitutes the most important site for viral replication due to the extensive presence of effector memory T-cells. In the case of HIV-controllers, several studies have reported fewer peripheral alterations and conserved immune responses that correlate with viral control; however, the histopathological characterization of GALT in those patients is still missing. In this study, we evaluated pathological alterations in GALT, trying to associate them with clinical parameters of HIV infected patients with or without evidence of viral control. METHODS: This study included eight HIV-controllers (antiretroviral treatment-naïve patients, with viral loads below 2.000 copies/mL for at least 1 year); 14 Noncontrollers (antiretroviral treatmentnaïve patients, with viral loads > 2.000 copies/mL and CD4+ T cells count > 250 cells/µL), and 12 uninfected donors. Biopsy fragments were obtained by rectosigmoidoscopy and stained with hematoxylin and eosin, silver methenamine, Ziehl Neelsen, and modified Ziehl Neelsen. RESULTS: Histopathological findings in HIV-controllers were similar to those observed in the uninfected group. In contrast, noncontrollers exhibited several alterations including condyloma acuminate, squamous metaplasia and acute colitis. These alterations were associated with disease progression. CONCLUSION: HIV-controllers exhibit lower pathological alterations in the gut tissue, associated with higher CD4 T cell count, and lower viral load.

HIV replication is associated to inflammasomes activation, IL-1ß, IL-18 and caspase-1 expression in GALT and peripheral blood.

BACKGROUND: Human immunodeficiency virus (HIV) promotes an inflammatory process, leading to the progressive loss of the functional capacity of the immune system. The HIV infection induces alterations in several tissues, but mainly in the gut-associated lymphoid tissue (GALT). However, the degree of GALT deterioration varies among infected individuals. In fact, it has been shown that HIV-controllers, who spontaneously control viral replication, exhibit a lower inflammatory response, and a relative normal frequency and function of most of the immune cells. Inflammasomes are molecular complexes involved in the inflammatory response, being NLRP1, NLRP3, NLRC4, AIM2 and Pyrin inflammasomes, the best characterized so far. These complexes regulate the maturation of cytokines of the IL-1 family, including IL-1ß and IL-18. These cytokines have been associated with immune activation and expansion of HIV target cells, promoting viral replication. Interesting, some reports indicate that HIV induces the activation of the NLRP3 inflammasome, but the role of this, and other inflammasomes during HIV infection, especially in GALT, remains unclear. OBJECTIVE: To compare the relative expression of inflammasome components and the proinflammatory response related to their activity, between HIV-progressors and HIV-controllers. METHODS: GALT biopsies and peripheral blood mononuclear cells (PBMCs) from 15 HIV-controllers and 15 HIV-progressors were obtained. The relative expression of the following inflammasome components were evaluated by RT-PCR: NLRP3, NLRC4, NLRP1, AIM2, ASC, Caspase-1, IL-1ß and IL-18. In addition, plasma concentration of IL-18 was evaluated as an indicator of baseline proinflammatory status. Finally, in supernatants of PBMCs in vitro stimulated with inflammasome agonists, the concentrations of IL-1ß and IL-18 were quantified by ELISA. RESULTS: HIV-progressors exhibited higher expression of IL-1ß, IL-18 and caspase-1 genes in GALT and PBMCs compared with HIV-controllers. In addition, HIV-progressors had also increased expression of ASC in PBMCs. When plasma levels were evaluated, IL-18 was increased in HIV-progressors. Interesting, these patients also showed an increased production of IL-1ß in supernatants of PBMCs stimulated in vitro with the agonists of AIM2, NLRP1 and NLRC4 inflammasomes. Finally, the expression of caspase-1, NLRP1, IL-1ß and IL-18 in GALT or peripheral blood was correlated with CD4+ T-cell count and viral load. CONCLUSION: Our results suggest that during HIV-infection, the required signals to induce the expression of different components of the inflammasomes are produced, both in GALT and in periphery. The activation of these molecular complexes could increase the number of target cells, favoring HIV replication and cell death, promoting the disease progression.

A Low Frequency of IL-17-Producing CD8+ T-Cells Is Associated With Persistent Immune Activation in People Living With HIV Despite HAART-Induced Viral Suppression.

Immune activation is the hallmark of HIV infection, even in patients with highly active anti-retroviral therapy (HAART)-induced viral suppression. A major cause of immune activation during HIV infection is the intestinal microbial translocation as a consequence, among other factors, of the decrease and/or dysfunction of interleukin (IL)-17-producing T-cells, due to their role promoting the integrity of the intestinal barrier. A population of IL-17-producing CD8+ T-cells (Tc17 cells), characterized by the expression of CD161, has been described, but its relation with the persistent immune activation in non-viremic people living with HIV (PLWH) on HAART is unclear. By flow cytometry, we characterized the activation phenotype (evaluated by the expression of HLA-DR and CD38) of circulating CD161-expressing CD8+ T-cells; in addition, we explored the functionality of polyclonally-stimulated Tc17 cells in PLWH under HAART-induced viral suppression, and in healthy individuals. Finally, we determined the association of Tc17 cells with the expression of cellular and soluble activation markers. Circulating CD161-expressing CD8+ T-cells were decreased in PLWH compared with healthy individuals, despite their similar basal activation state. After polyclonal stimulation, IL-17 production was higher in CD8+ T-cells co-expressing HLA-DR and CD38 in healthy individuals. In contrast, although PLWH had a higher frequency of HLA-DR+ CD38+ CD8+ T-cells after stimulation, they had a lower production of IL-17. Interferon (IFN)-γ-producing CD8+ T-cells (Tc1 cells) were increased in PLWH. The low Tc17 cells response was associated with a high expression of CD38 and programmed death 1 protein, high levels of soluble CD14 and the treatment duration. Finally, to explore potential immunomodulatory strategies, the in vitro effect of the anti-inflammatory agent sulfasalazine was assessed on Tc17 cells. Interestingly, a decreased inflammatory environment, death of activated CD8+ T-cells, and an increased frequency of Tc17 cells were observed with sulfasalazine treatment. Thus, our findings suggest that activated CD8+ T-cells have a marked capacity to produce IL-17 in healthy individuals, but not in PLWH, despite HAART. This dysfunction of Tc17 cells is associated with the persistent immune activation observed in these patients, and can be partially restored by anti-inflammatory agents.

High Expression of Antiviral Proteins in Mucosa from Individuals Exhibiting Resistance to Human Immunodeficiency Virus.

BACKGROUND: Several soluble factors have been reported to have the capacity of inhibiting HIV replication at different steps of the virus life cycle, without eliminating infected cells and through enhancement of specific cellular mechanisms. Yet, it is unclear if these antiviral factors play a role in the protection from HIV infection or in the control of viral replication. Here we evaluated two cohorts: i) one of 58 HIV-exposed seronegative individuals (HESNs) who were compared with 59 healthy controls (HCs), and ii) another of 13 HIV-controllers who were compared with 20 HIV-progressors. Peripheral blood, oral and genital mucosa and gut-associated lymphoid tissue (GALT) samples were obtained to analyze the mRNA expression of ELAFIN, APOBEC3G, SAMHD1, TRIM5α, RNase 7 and SerpinA1 using real-time PCR. RESULTS: HESNs exhibited higher expression of all antiviral factors in peripheral blood mononuclear cells (PBMCs), oral or genital mucosa when compared with HCs. Furthermore, HIV-controllers exhibited higher levels of SerpinA1 in GALT. CONCLUSIONS: These findings suggest that the activity of these factors is compartmentalized and that these proteins have a predominant role depending on the tissue to avoid the infection, reduce the viral load and modulate the susceptibility to HIV infection.

Magnesium sulphate injected subcutaneously suppresses autotomy in peripherally deafferented rats.

In rats, recent evidence suggests that injury discharge caused by peripheral nerve section releases excitatory amino acids into the spinal cord which in turn influences decisively the development of autotomy, a self-mutilation behaviour directed towards the denervated areas. Autotomy has been proposed as a behavioural correlate of the neuropathic pain which occurs in humans after complete nerve lesions. Mg2+ ions have been shown to offer protection from neurological and degenerative disorders in which excitatory amino acids are putatively involved. To ascertain the preventive value of Mg2+ administration on autotomy, male rats underwent unilateral ligation and transection of the sciatic and saphenous nerves 30 min after being injected subcutaneously (s.c.) with 300 or 600 mg/kg MgSO4 or saline. Thereafter, autotomy was monitored for 8 weeks. Serum, lumbosacral (L1-S1) and brain magnesium levels were analyzed 0, 30, 60, 120, 180, 240, 360 min and 24 h after the s.c. injection of 600 mg/kg MgSO4. Serum magnesium levels increased quickly from 1.02 mM (0 time) to 4.52 mM (at 60 min) and dropped afterwards to reach physiological levels at 6 h. Peak increments in L1-S1 and brain Mg2+ levels were smaller (32% and 30%, respectively) although maintained for at least 6 h. Magnesium pretreatment in a significant and dose-dependent manner (1) largely suppressed autotomy, (2) decreased final autotomy scores, (3) delayed autotomy onset, and (4) decreased the percentage of animals engaged in high autotomy behaviors. The data support a role for excitatory amino acids in determining susceptibility to autotomy and suggest a hopeful way to prevent neuropathic pain in humans after peripheral deafferentation.

Effects of selective neurotoxic lesion of lumbosacral serotonergic and noradrenergic systems on autotomy behaviour in rats.

Male rats underwent unilateral ligation and transection of the sciatic and saphenous nerves 2, 7 or 14 days after being injected intrathecally (at the thoracolumbar junction) with 6-hydroxydopamine (6-OHDA), 5,6-dihydroxytryptamine (5,6-DHT) or vehicle, and the development of autotomy was monitored. The effects of both neurotoxins on cervicothoracic (C5-T1) and lumbosacral (L1-S1) norepinephrine (NE), dopamine (DA) and 5-hydroxytryptamine (5-HT) spinal cord levels were analysed by HPLC in separate groups of rats. 6-OHDA treatment (20 micrograms/10 microliters) produced a rapid (from day 2) and significant (90-95%) fall in NE content only at L1-S1. 5,6-DHT administration (20 micrograms/10 microliters) produced a gradual (68%, 90% and 94%, at 2, 7 and 14 days, respectively) and selective depletion of 5-HT only at L1-S1. DA levels remained essentially unchanged after both neurotoxins. No differences in monoamine levels were detected among groups injected with vehicle. The main effects of neurotoxins on autotomy were: (1) a significant delay in the onset of autotomy in the rats injected with 6-OHDA 2 days before neurectomy; (2) a trend to autotomize earlier and more severely in the rats injected with 5,6-DHT 7 days before neurectomy and (3) an almost complete suppression of autotomy in the rats injected with 5,6-DHT 14 days before neurectomy. These results revealed that the expression of autotomy in rats can be modulated by interfering with spinal cord serotonergic activity and suggest new possible avenues for the treatment of certain specific pain diseases, such a phantom limb pain, by using selective agents capable of activating or blocking spinal cord serotonergic receptor subtypes.

Relationship between autotomy behaviour and spinal cord monoaminergic levels in rats.

In the rat, unilateral neurectomy of the sciatic and saphenous nerves causes autotomy, a self-mutilation behaviour, against the denervated limb that is variable in both its onset and severity. To study some of the possible neurochemical sources of this variability, spinal cord levels of norepinephrine (NE), dopamine (DA), serotonin (5-HT0 and 5-hydroxyindoleacetic acid (5-HIAA) were analysed ipsi- and contralateral to the lesioned side by high performance liquid chromatography at C5-T1 and L1-S1. According to the early or late onset and to the slight or intense autotomy behaviour, the animals were assigned to four different groups: early autotomy, early no autotomy, late autotomy, and late no autotomy. Two sham-operated groups were sacrificed at an early or late stage in the postoperative period. The spinal cord NE content remained unchanged throughout the different experimental situations. The more conspicuous changes observed were: (1) a generalized increase in spinal 5-HT metabolism in all deafferented groups; (2) a significant and selective increase in lumbosacral 5-HT and 5-HIAA levels of the rats that did not self-lesion for 8 weeks after deafferentation and (3) a significant fall (30-45%) in DA levels at denervated spinal segments of the rats that actively self-attacked late in the postoperative period. The data suggests that spinal cord serotonergic and dopaminergic influences play an important role in determining the susceptibility to autotomy (and perhaps chronic pain) after peripheral deafferentation.

Superoxide anion mediates the L-selectin down-regulation induced by non-steroidal anti-inflammatory drugs in human neutrophils.

UNLABELLED: Non-steroidal anti-inflammatory drugs (NSAIDs) induce the shedding of L-selectin in human neutrophils through a mechanism still not well understood. In this work we studied both the functional effect of NSAIDs on the neutrophils/endothelial cells dynamic interaction, and the potential involvement of reactive oxygen species (ROS) in the NSAIDs-mediated down-regulation of L-selectin. When human neutrophils were incubated with diclofenac, a significant reduction in the number of cells that rolled on activated endothelial cells was observed. Different NSAIDs (flufenamic acid, meclofenamic acid, diclofenac, indomethacin, nimesulide, flurbiprofen, meloxicam, phenylbutazone, piroxicam, ketoprofen and aspirin) caused variable increase in neutrophil intracellular ROS concentration, which was inversely proportional to the change produced in L-selectin surface expression. Pre-incubation of neutrophils with superoxide dismutase, but not with catalase, showed both a significant protective effect on the L-selectin down-regulation induced by several NSAIDs and a diminished effect of diclofenac on neutrophil rolling. Interestingly, diclofenac and flufenamic acid but not piroxicam significantly increased the extracellular superoxide anion production by neutrophils, and inhibition of nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase activity with diphenyleneiodonium prevented the down-regulation of L-selectin by diclofenac. In accordance with these results, neutrophils from patients with chronic granulomatous disease, a hereditary disease in which neutrophils show a reduced capacity to form superoxide radicals, exhibited a lower down-regulation of L-selectin (IC50: 15.3 µg/ml) compared to normal controls (IC50: 5.6 µg/ml) in response to diclofenac. CONCLUSION: A group of NSAIDs is capable of interfering with the ability of neutrophils to interact with endothelial cells by triggering L-selectin-shedding through the NADPH-oxidase-dependent generation of superoxide anion at the plasma membrane.

Integral valorization of Leucaena diversifolia by hydrothermal and pulp processing.

Wood from the leguminous tree, Leucaena diversifolia, was subjected to hydrothermal treatment (autohydrolysis) at 160-180 °C for 0-30 min followed by ethanol-soda-anthraquinone delignification. The liquid phase contained 18.65 g of sugars per liter, and the solid phase had a gross heating value of 19.083 MJ/kg, but could also be used as a source of cellulose pulp for the production of paper with tear, burst, and tensile indexes of 2.4 N m2/kg, 2.6 MPa m2/kg and 40.7 kN m/kg, respectively. L. diversifolia lends itself readily to valorization for energy production, and also to integral, fractional exploitation by autohydrolysis and ethanol-soda-anthraquinone delignification, which can additionally bring environmental benefits to cropping zones.

Efecto de la terapia con probióticos/prebióticos sobre la reconstitución del tejido linfoide asociado a la mucosa gastrointestinal durante la infección por el virus de la inmunodeficiencia humana-1 / Effects of prebiotics and probiotics on gastrointestinal tract lymphoid tissue in hiv infected patients

HIV infection induces alterations in almost all immune cell populations, mainly in CD4+ T cells, leading to the development of opportunistic infections. The gut-associated lymphoid tissue (GALT) constitutes the most important site for viral replication, because the main target cells, memory T-cells, reside in this tissue. It is currently known that alterations in GALT are critical during the course of the infection, as HIV-1 induces loss of tissue integrity and promotes translocation of microbial products from the intestinal lumen to the systemic circulation, leading to a persistent immune activation state and immune exhaustion. Although antiretroviral treatment decreases viral load and substantially improves the prognosis of the infection, the alterations in GALT remains, having a great impact on the ability to establish effective immune responses. This emphasizes the importance of developing new therapeutic alternatives that may promote structural and functional integrity of this tissue. In this regard, therapy with probiotics/prebiotics has beneficial effects in GALT, mainly in syndromes characterized by intestinal dysbiosis, including the HIV-1 infection. In these patients, the consumption of probiotics/prebiotics decreased microbial products in plasma and CD4+ T cell activation, increased CD4+ T cell frequency, in particular Th17, and improved the intestinal flora. In this review, the most important findings on the potential impact of the probiotics/prebiotics therapy are discussed.

A strategy for conversion from subcutaneous to oral ketamine in cancer pain patients: effect of a 1:1 ratio.

CONTEXT: No consensus exists about the most appropriate dose ratio for conversion from parenteral to oral ketamine. OBJECTIVES: To confirm that a 1:1 dose ratio is suitable for converting subcutaneous (s.c.) to oral ketamine in cancer patients. METHODS: Patients with opioid poorly responsive cancer pain, who responded to 0.4, 0.6, or 0.8 mg s.c. ketamine bolus, were treated with 0.1, 0.15, or 0.2mg/kg/h ketamine infusion, respectively. Switching to the oral route, by applying a 1:1 dose ratio, was carried out in patients who experienced adequate pain relief and continued to need ketamine as a coanalgesic. Pain, somnolence, feelings of insobriety, confusion, and cardiovascular parameters were assessed throughout the process. RESULTS: Twenty-nine patients were enrolled in the study. Ketamine infusion decreased pain intensity from severe to no pain or slight pain in 23 of 29 and six of 29 patients, respectively. The median of s.c. ketamine doses was 0.2mg/kg/h (range 0.1-0.5). After oral switching, 27 of 29 patients remained as successfully controlled as when receiving s.c. ketamine. The other two patients needed a slight dose ratio readjustment, to 1:1.3 and 1:1.5, to maintain pain control. The median of oral ketamine doses was 300 mg/day (interquartile range 240-382.5). Seven of 29 patients receiving s.c. ketamine developed moderate and transitory side effects, such as feelings of insobriety and somnolence. No side effects were present while receiving oral ketamine. No significant changes were observed in cardiovascular parameters. CONCLUSION: A 1:1 dose ratio for conversion from s.c. to oral ketamine is safe and effective in cancer pain patients.