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1.

Background

Data on suppression of HIV replication in the CNS and on the subsequent risk of neurocognitive impairment using monotherapy with boosted protease inhibitors are limited.

Methods

Ours was an exploratory cross-sectional study in patients on lopinavir/ritonavir-based monotherapy (LPV/r-MT) or standard triple therapy (LPV/r-ART) for at least 96 weeks who maintained a plasma viral load <50 copies/mL. HIV-1 RNA in CSF was determined by HIV-1 SuperLow assay (lower limit of detection, 1 copy/mL). Neurocognitive functioning was assessed using a recommended battery of neuropsychological tests covering 7 areas. Neurocognitive impairment (NCI) was determined and also a global deficit score (GDS) for study comparisons.

Results

Seventeen patients on LPV/r-MT and 17 on LPV/r-ART were included. Fourteen (82.4%) patients on LPV/r-MT and 16 (94.1%) on LPV/r-ART had HIV-1 RNA <1 copy/mL in CSF (p = 0.601). NCI was observed in 7 patients on LPV/r-MT and in 10 on LPV/r-ART (41% vs 59%; p = 0.494). Mean (SD) GDS was 0.22 (0.20) in patients on LPV/r-MT and 0.47 (0.34) in those on LPV/r-ART (p = 0.012).

Conclusions

Suppression of HIV in CSF is similar in individuals with durable plasma HIV-1 RNA suppression who are receiving LPV/r-MT or LPV/r-ART for at least 96 weeks. Findings for HIV-1 replication in CSF and neurocognitive status indicate that this strategy seems to be safe for CNS functioning.  相似文献   
2.
An interdisciplinary approach employing functionalized nanoparticles and ultrasensitive spectroscopic techniques is reported here to track the molecular changes in early stage of malignancy. Melanoma tissue tracking at molecular level using both labelled and unlabelled silver and gold nanoparticles has been achieved using surface enhanced Raman scattering (SERS) technique. We used skin tissue from ex vivo mice with induced melanoma. Raman and SERS molecular characterization of melanoma tissue is proposed here for the first time. Optical nanosensors based on Ag and Au nanoparticles with chemisorbed cresyl violet molecular species as labels revealed sensitive capability to tissues tagging and local molecular characterization. Sensitive information originating from surrounding native biological molecules is provided by the tissue SERS spectra obtained either with visible or NIR laser line. Labelled nanoparticles introduced systematic differences in tissue response compared with unlabelled ones, suggesting that the label functional groups tag specific tissue components revealed by proteins or nucleic acids bands. Vibrational data collected from tissue are presented in conjunction with the immunohistochemical analysis. The results obtained here open perspectives in applied plasmonic nanoparticles and SERS for the early cancer diagnostic based on the appropriate spectral databank.  相似文献   
3.
miR-33 and miR-122 are major regulators of lipid metabolism in the liver, and their deregulation has been linked to the development of metabolic diseases such as obesity and metabolic syndrome. However, the biological importance of these miRNAs has been defined using genetic models. The aim of this study was to evaluate whether the levels of miR-122 and miR-33a in rat liver correlate with lipemia in nutritional models. For this purpose, we analyzed the levels of miRNA-33a and miR-122 in the livers of dyslipidemic cafeteria diet-fed rats and of cafeteria diet-fed rats supplemented with proanthocyanidins and/or ω-3 PUFAs because these two dietary components are well-known to counteract dyslipidemia. The results showed that the dyslipidemia induced in rats that were fed a cafeteria diet resulted in the upregulation of miR-33a and miR-122 in the liver, whereas the presence of proanthocyanidins and/or ω-3 PUFAs counteracted the increase of these two miRNAs. However, srebp2, the host gene of miR-33a, was significantly repressed by ω-3 PUFAs but not by proanthocyanidins. Liver mRNA levels of the miR-122 and miR-33a target genes, fas and pparβ/δ, cpt1a and abca1, respectively, were consistent with the expression of these two miRNAs under each condition. Moreover, the miR-33a and abca1 levels were also analyzed in PBMCs. Interestingly, the miR-33a levels evaluated in PBMCs under each condition were similar to the liver levels but enhanced. This demonstrates that miR-33a is expressed in PBMCs and that these cells can be used as a non-invasive way to reflect the expression of this miRNA in the liver. These findings cast new light on the regulation of miR-33a and miR-122 in a dyslipidemic model of obese rats and the way these miRNAs are modulated by dietary components in the liver and in PBMCs.  相似文献   
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Porcine reproductive and respiratory syndrome virus (PRRSV) has been reported to be shed in the semen of infected boars. To determine whether the reproductive tissues could be a persistent source of virus and the possible origin of PRRSV found in semen of infected boars, 20 PRRSV-seronegative boars were intranasally inoculated with 5 x 10(6) median tissue culture infective doses (TCID50) of PRRSV and necropsied at different times post-inoculation (p.i.) from Day 2 to Day 37 p.i. Blood samples were collected before experimental inoculation, at necropsy and at different times p.i. At necropsy, epididymal semen and reproductive tissues were collected and the presence of the virus determined by virus isolation. The infection of the boars was demonstrated by the isolation of the virus from the sera of all inoculated boars and by seroconversion. PRRSV was detected in serum samples from Day 2 to Day 23 p.i., although the viremic period was largely dependent on the individual response to infection. Viral replication was proven within different reproductive tissues from Day 2 to Day 23 p.i., being most consistently found in the epididymus. In addition, PRRSV was isolated in semen from Day 4 to Day 10 p.i. The correlation of a diminished viremia and the inability to isolate PRRSV from semen or reproductive tissues may be due to one of two possibilities. First, viremia is responsible for most of the virus isolated from reproductive tissues due to the movement of PRRSV-infected cells out of the blood and into the tissues. Second, viremia may initially seed the reproductive tissues with PRRSV, and then the virus is produced into the reproductive tract and shed into semen at low levels.  相似文献   
6.
Bioactive proanthocyanidins have been reported to have several beneficial effects on health in relation to metabolic syndrome, type 2 diabetes, and cardiovascular disease. We studied the effect of grape seed proanthocyanidin extract (GSPE) in rats fed a high fat diet (HFD). This is the first study of the effects of flavonoids on the liver proteome of rats suffering from metabolic syndrome. Three groups of rats were fed over a period of 13 weeks either a chow diet (control), an HFD, or a high fat diet supplemented for the last 10 days with GSPE (HFD + GSPE). The liver proteome was fractionated, using a Triton X-114-based two-phase separation, into soluble and membrane protein fractions so that total proteome coverage was considerably improved. The data from isobaric tag for relative and absolute quantitation (iTRAQ)-based nano-LC-MS/MS analysis revealed 90 proteins with a significant (p < 0.05) minimal expression difference of 20% due to metabolic syndrome (HFD versus control) and 75 proteins due to GSPE treatment (HFD + GSPE versus HFD). The same animals have previously been studied (Quesada, H., del Bas, J. M., Pajuelo, D., Díaz, S., Fernandez-Larrea, J., Pinent, M., Arola, L., Salvadó, M. J., and Bladé, C. (2009) Grape seed proanthocyanidins correct dyslipidemia associated with a high-fat diet in rats and repress genes controlling lipogenesis and VLDL assembling in liver. Int. J. Obes. 33, 1007–1012), and GSPE was shown to correct dyslipidemia observed in HFD-fed rats probably through the repression of hepatic lipogenesis. Our data corroborate those findings with an extensive list of proteins describing the induction of hepatic glycogenesis, glycolysis, and fatty acid and triglyceride synthesis in HFD, whereas the opposite pattern was observed to a large extent in GSPE-treated animals. GSPE was shown to have a wider effect than previously thought, and putative targets of GSPE involved in the reversal of the symptoms of metabolic syndrome were revealed. Some of these novel candidate proteins such as GFPT1, CD36, PLAA (phospholipase A2-activating protein), METTL7B, SLC30A1, several G signaling proteins, and the sulfide-metabolizing ETHE1 and SQRDL (sulfide-quinone reductase-like) might be considered as drug targets for the treatment of metabolic syndrome.An increase in high calorie diets and a sedentary lifestyle are considered the key factors in explaining the epidemic rise in obesity in developed countries (1). Obese patients, especially those with abdominal obesity due to visceral adipose tissue accumulation, run a higher risk of impaired glucose tolerance, which frequently evolves into insulin resistance (2). Obesity and insulin resistance are frequently associated with hypertension, proatherogenic dyslipidemia, chronic inflammation, a prothrombotic state, and recently also fatty liver (3), conditions that together make up what is known as metabolic syndrome and lead to an increased risk of developing cardiovascular disease (CVD)1 and type 2 diabetes (4). Conversely, some dietary patterns and specific food components have been associated with a lower prevalence of obesity, type 2 diabetes, and CVD. In this sense, the traditional Mediterranean diet (characterized by a high fiber content, low glycemic index carbohydrates, unsaturated fats, vitamins, and antioxidant polyphenols) has been linked to a lower incidence of CVD, obesity, and type 2 diabetes (58). Moreover, the French population presents a very low prevalence of death due to CVD despite consuming a diet rich in saturated fats and cholesterol. This phenomenon, known as “the French paradox” (9), has been ascribed to the moderate consumption of red wine and specifically to its content of polyphenols (1012).Polyphenols include flavonoids of which flavan-3-ols and their oligomeric forms (proanthocyanidins) have been reported to exhibit several beneficial health effects by acting as antioxidant, anticarcinogen, cardioprotective, antimicrobial, antiviral, and neuroprotective agents (for a review, see Ref. 13). Specifically, grape and wine proanthocyanidins have a cardioprotective effect through increasing plasma high density lipoprotein cholesterol, decreasing low density lipoprotein-derived atherosclerotic foam cell lesions, attenuating oxidant formation by quenching harmful radicals, increasing endothelium-dependent vasorelaxation, etc. (13). In this context, our group has been working for years on the effect of a grape seed proanthocyanidin extract (GSPE) (containing monomers and oligomers of flavan-3-ols) in relation to metabolic syndrome. In previous works, we have found that GSPE prevents oxidative injury (14), has an insulinomimetic effect on adipocytes and adipose tissue (15), modulates glucose homeostasis (16), decreases plasma levels of triglycerides (TGs) and apolipoprotein B in normolipidemic rats (17), and acts as an in vitro (18, 19) and in vivo (20) anti-inflammatory. We have also shown that GSPE decreases postprandial plasma TG and apolipoprotein B in mice through a hepatic induction of a farnesoid X receptor (FXR) and the small heterodimer partner (SHP) that in turn down-regulates SREBP1c and other lipogenic genes in the liver (21, 22). Furthermore, we have demonstrated that the molecules responsible for the reduced TG synthesis in HepG2 cells treated with GSPE are the sum of a proanthocyanidins trimer and a dimer gallate because they reproduce the GSPE effect (23).The effect of GSPE on metabolic syndrome has been studied in our laboratory by feeding rats a “cafeteria diet.” This diet is an experimental model of a western high sugar and high fat diet extensively used to produce obesity in rats because its palatability induces the animals to increase their energy intake (24). In a recent study conducted by our group (25) as well as this study, the rats were fed a high fat diet (HFD) (cafeteria diet) for 13 weeks, and one group of the animals was treated with a daily dose of GSPE (25 mg/kg of body weight) for the last 10 days (HFD + GSPE). In that study, HFD was shown to cause the animals to be overweight and to suffer from fatty liver, dyslipidemia, and hepatic overexpression of key genes involved in lipogenesis and VLDL assembly, whereas GSPE treatment corrected dyslipidemia and down-regulated some of the genes up-regulated by HFD (25).To better investigate the mechanism behind the changes observed in HFD- and HFD + GSPE-fed rats, we analyzed protein expression in the liver. Because GSPE treatment and obesity have multiple effects, a proteome-wide approach is needed to map proteins from different pathways. Proteomics studies related to obesity, metabolic syndrome, fatty liver, or insulin resistance have previously been performed on the liver (2632). Two such studies looked into the effects of flavonoids in mouse livers (33, 34), but to our knowledge, this is the first hepatic proteome analysis of the effect of flavonoids in rats suffering from metabolic syndrome. To improve the proteome coverage of the complex liver samples, we performed a proteome fractionation according to protein solubility using a two-phase detergent protocol (35). This strategy was advantageous because it captured membrane proteins that otherwise would have been difficult to detect. The resulting soluble and membrane protein fractions were digested, iTRAQ-labeled, fractionated according to isoelectric point, and analyzed by nano-LC-MS/MS. The proteomics study presented here reports a differential expression due to HFD or HFD + GSPE for approximately 140 proteins, indicating that both conditions were potent modifiers of the liver proteome. We have focused on the sugar and lipid metabolism data, which confirmed the repression of hepatic lipogenesis in HFD + GSPE rats. Additionally, new proteins have been revealed as putative GSPE targets.  相似文献   
7.
8.
In recent years, studies on arbuscular mycorrhizal fungi (AMF) have been revealing that the belowground symbiosis can influence the performance of aboveground herbivores and their natural enemies through its effects on the host plant. In this study, we tested whether the colonization of tomato plants by the arbuscular mycorrhizal fungus Rhizophagus irregularis (Syn. Glomus intraradices Schenk and Smith) (Glomeromycota: Glomeraceae) affects the performance of the zoophytophagous mirid bug Macrolophus pygmaeus Rambur (Hemiptera: Miridae). Mycorrhizal colonization in tomato plants positively influenced the predator host-plant acceptance for feeding and oviposition, as well as nymphal survival and female weight. We hypothesize that AMF can modify mirid bug foraging behavior and performance.  相似文献   
9.
A study was conducted with the vine rootstock Richter 110 (Vitis berlandieri Planch. x Vitis rupestris L.) in order to assess whether the colonisation by the arbuscular mycorrhizal fungus (AMF) Glomus intraradices (BEG 72) can delay the disease development in plants inoculated with the root-rot fungus Armillaria mellea (Vahl:Fr) Kummer, and to elucidate if the levels of polyamines (PAs) are modified in response to G. intraradices, A. mellea or by the dual infection. Four treatments were considered: control and G. intraradices-inoculated plants infected or not with A. mellea. Plant growth, mycorrhizal colonisation and disease development were monitored throughout the experiment. High performance liquid chromatography (HPLC) in combination with fluorescence spectrophotometry was used to separate and quantify free root and leaf polyamines. The slower development of pathogenic symptoms and the higher plant biomass of mycorrhizal plants inoculated with A. mellea indicate an increase of tolerance due to the AMF inoculation. The variations in free PA levels detected at the beginning of the pathogenic infection suggest that PAs may have a potential role in the signalling mechanisms of the tolerance of mycorrhizal plants against A. mellea.  相似文献   
10.
ObjectiveThe main objective of this study was to evaluate the effect of procyanidin intake on the level of inflammatory mediators in rats fed a hyperlipidic diet, which are a model of low-grade inflammation as they show an altered cytokine production.DesignMale Zucker Fa/fa rats were randomly grouped to receive a low-fat (LF) diet, a high-fat (HF) diet or a high-fat diet supplemented with procyanidins from grape seed (HFPE) (345 mg/kg feed) for 19 weeks and were then euthanized. We determined biochemical parameters, C-reactive protein (CRP) and IL-6 levels in plasma. Adipose tissue depots and body weight were also determined. We assessed CRP, IL-6, TNF-α and adiponectin gene expression in liver and white adipose tissue (WAT).ResultsAs expected, rats fed the HF diet show an enhanced production of CRP. Our results demonstrate that the HFPE diet decreases rat plasma CRP levels but not IL-6 levels. The decrease in plasma CRP in HFPE rats is related to a down-regulation of CRP mRNA expression in the liver and mesenteric WAT. We have also shown a decrease in the expression of the proinflammatory cytokines TNF-α and IL-6 in the mesenteric WAT. In contrast, adiponectin mRNA is increased in this tissue due to the procyanidin treatment.As previously reported, CRP plasma levels correlate positively with its expression in the mesenteric WAT, suggesting that procyanidin extract (PE) modulates CRP at the synthesis level. CRP plasma levels also correlate positively with body weight. As expected, body weight is associated with the adiposity index. Also, TNF-α expression and IL-6 expression have a strong positive correlation. In contrast, the expression of the anti-inflammatory cytokine adiponectin correlates negatively with the expression of TNF-α and IL-6 in the mesenteric WAT.ConclusionThese results suggest a beneficial effect of PE on low-grade inflammatory diseases, which may be associated with the inhibition of the proinflammatory molecules CRP, IL-6 and TNF-α and the enhanced production of the anti-inflammatory cytokine adiponectin. These findings provide a strong impetus to explore the effects of dietary polyphenols in reducing obesity-related adipokine dysregulation to manage cardiovascular and metabolic risk factors.  相似文献   
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