ApoE-modified solid lipid nanoparticles: A feasible strategy to cross the blood-brain barrier.

Solid lipid nanoparticles (SLN) are colloidal drug delivery systems characterized by higher entrapment efficiency, good scalability of the preparation process and increased sustained prolonged release of the payload compared to other nanocarriers. The possibility to functionalize the surface of SLN with ligands to achieve a site specific targeting makes them attractive to overcome the limited blood-brain barrier (BBB) penetration of therapeutic compounds. SLN are prepared for brain targeting by exploiting the adaptability of warm microemulsion process for the covalent surface modification with an Apolipoprotein E-derived peptide (SLN-mApoE). Furthermore, the influence of the administration route on SLN-mApoE brain bioavailability is here evaluated. SLN-mApoE are able to cross intact a BBB in vitro model. The pulmonary administration of SLN-mApoE is related to a higher confinement in the brain of Balb/c mice compared to the intravenous and intraperitoneal administration routes, without inducing any acute inflammatory reaction in the lungs. These results promote the pulmonary administration of brain-targeted SLN as a feasible strategy for improving brain delivery of therapeutics.

Inhibition of ceramide de novo synthesis as a postischemic strategy to reduce myocardial reperfusion injury.

The injury caused by myocardial reperfusion after ischemia can be contained by interventions aimed at reducing the inflammation and the oxidative stress that underlie exacerbation of tissue damage. Sphingolipids are a class of structural and signaling lipid molecules; among them, the inflammation mediator ceramide accumulates in the myocardium upon ischemia/reperfusion. Here, we show that, after transient coronary occlusion in mice, an increased de novo ceramide synthesis takes place at reperfusion in the ischemic area surrounding necrosis (area at risk). This correlates with the enhanced expression of the first and rate-limiting enzyme of the de novo pathway, serine palmitoyltransferase (SPT). The intraventricular administration at reperfusion of myriocin, an inhibitor of SPT, significantly protected the area at risk from damage, reducing the infarcted area by 40.9 % relative to controls not treated with the drug. In the area at risk, myriocin downregulated ceramide, reduced the content in other mediators of inflammation and reactive oxygen species, and activated the Nrf2-HO1 cytoprotective response. We conclude that an enhanced ceramide synthesis takes part in ischemia/reperfusion injury and that myriocin treatment can be proposed as a strategy for myocardial pharmacological postconditioning.

Solid lipid nanoparticles of cholesteryl butyrate inhibit the proliferation of cancer cells in vitro and in vivo models.

BACKGROUND AND PURPOSE: Solid lipid nanoparticles containing cholesteryl butyrate (cholbut SLN) can be a delivery system for the anti-cancer drug butyrate. These nanoparticles inhibit adhesion of polymorphonuclear and tumour cells to endothelial cells and migration of tumour cells, suggesting that they may act as anti-inflammatory and anti-tumour agents. Here we have evaluated the effects of cholbut SLN on tumour cell growth using in vitro and in vivo models. EXPERIMENTAL APPROACH: Cholbut SLNs were incubated with cultures of four tumour cell lines, and cell growth was analysed by assessing viability, clonogenic capacity and cell cycle. Effects on intracellular signalling was assessed by Western blot analysis of Akt expression. The in vivo anti-tumour activity was measured in two models of PC-3 cell xenografts in SCID/Beige mice. KEY RESULTS: Cholbut SLN inhibited tumour cell line viability, clonogenic activity, Akt phosphorylation and cell cycle progression. In mice injected i.v. with PC3-Luc cells and treated with cholbut SLN, . in vivo optical imaging and histological analysis showed no metastases in the lungs of the treated mice. In another set of mice injected s.c. with PC-3 cells and treated with cholbut SLN when the tumour diameter reached 2 mm, analysis of the tumour dimensions showed that treatment with cholbut SLN substantially delayed tumour growth. CONCLUSION AND IMPLICATIONS: Cholbut SLN were effective in inhibiting tumour growth in vitro and in vivo. These effects may involve, in part, inhibition of Akt phosphorylation, which adds another mechanism to the activity of this multipotent drug.

Cholesteryl butyrate solid lipid nanoparticles inhibit the adhesion and migration of colon cancer cells.

BACKGROUND AND PURPOSE Cholesteryl butyrate solid lipid nanoparticles (cholbut SLN) provide a delivery system for the anti-cancer drug butyrate. These SLN inhibit the adhesion of polymorphonuclear cells to the endothelium and may act as anti-inflammatory agents. As cancer cell adhesion to endothelium is crucial for metastasis dissemination, here we have evaluated the effect of cholbut SLN on adhesion and migration of cancer cells. EXPERIMENTAL APPROACH Cholbut SLN was incubated with a number of cancer cell lines or human umbilical vein endothelial cells (HUVEC) and adhesion was quantified by a computerized micro-imaging system. Migration was detected by the scratch 'wound-healing' assay and the Boyden chamber invasion assay. Expression of ERK and p38 MAPK was analysed by Western blot. Expression of the mRNA for E-cadherin and claudin-1 was measured by RT-PCR. KEY RESULTS Cholbut SLN inhibited HUVEC adhesiveness to cancer cell lines derived from human colon-rectum, breast, prostate cancers and melanoma. The effect was concentration and time-dependent and exerted on both cancer cells and HUVEC. Moreover, these SLN inhibited migration of cancer cells and substantially down-modulated ERK and p38 phosphorylation. The anti-adhesive effect was additive to that induced by the triggering of B7h, which is another stimulus inhibiting both ERK and p38 phosphorylation, and cell adhesiveness. Furthermore, cholbut SLN induced E-cadherin and inhibited claudin-1 expression in HUVEC. CONCLUSION AND IMPLICATIONS These results suggest that cholbut SLN could act as an anti-metastastic agent and they add a new mechanism to the anti-tumour activity of this multifaceted preparation of butyrate.

Paclitaxel-loaded polyester nanoparticles prepared by spray-drying technology: in vitro bioactivity evaluation.

Paclitaxel (PTX), an antimicrotubular agent used in the treatment of ovarian and breast cancer, was encapsulated in nanoparticles (NPs) of poly(lactide-co-glycolide) (PLGA) and poly(ε-caprolactone) (PCL) polymers using the spray-drying technique. Morphology, size distribution, drug encapsulation efficiency, thermal degradation and drug release were characterized. MCF7 cells were employed to evaluate the efficacy of the systems on cell cycle and cytotoxicity. The particle size was in the range 0.8-1 µm. The incorporation efficiency of PTX was more than 80% in all NPs obtained. In vitro drug release took place during 35 days, and drug release rates were in the order PCL > PLGA 50:50 > PLGA 75:25. Unloaded NPs showed to be cytocompatible at MCF7 cells. PTX-loaded NPs demonstrated the release of the drug block cells in the G2/M phase. All PTX-loaded formulations showed their efficacy in killing MCF7 cells, mainly PTX-loaded PLGA 50:50 and PLGA 75:25 that cause a decrease in cell viability lower than 20%.

Cellular uptake of coumarin-6 as a model drug loaded in solid lipid nanoparticles.

The aim of present work was to elucidate the interaction of solid lipid nanoparticles (SLNs) with cellular plasma-membrane to gain insight of intracellular drug delivery. To this aim we followed the uptake of coumarin-6 (a drug model) either free in the extracellular medium or loaded on SLN (c-SLN). Alveolar epithelial cells were exposed to a biocompatible concentration of c-SLN (0.01 mg/ml of tripalmitin) prepared by warm microemulsion whose lipid matrix was constituted by low melting point molecules (fatty acids, triglycerides). Intracellular fluorescence and preferential accumulation in the perinuclear region were increased by 54.8% on comparing c-SLN to the same amount of free coumarin-6 in the medium. Lowering temperature from 37 ° to 4 °C decreased the intracellular signal intensity by about 48% equally for the free as well as for loaded drug, thus suggesting the inhibition of a similar non-endocytotic entrance pathway. No specific co-localization of the fluorescence with intracellular organelles was found. The c-SLN calorimetric profile obtained with differential scanning calorimetry (DSC), revealing transition within the range 58-62 °C, altered remarkably upon incubation with cells, suggesting a change in SLN structure after association with cells membranes. We propose that the uptake of the model drug loaded on SLN is only partly related to the endocytotic pathway; it occurs despite the loss of integrity of the original SLN structure and it appears to be more efficient when the drug is vehicled rather than being free in the culture medium.

Predictors of severe hepatic steatosis using abdominal ultrasound in HIV-infected patients.

OBJECTIVE: Multiple factors may lead to hepatic steatosis (HS) in HIV-positive patients. HS may result in severe liver damage on its own and/or by accelerating the progression of chronic viral hepatitis B or C. METHODS: The sensitivity/specificity of liver ultrasound (US) to recognize severe HS is above 85%. A cross-sectional case-control study of all HIV out-patients who underwent liver US since 2004 was conducted at our institution. RESULTS: Eight hundred and thirty (36.1%) out of 2300 HIV-positive patients on regular follow-up underwent liver US during the study period. Severe HS was diagnosed in 108 (13%) patients. A total of 117 matched HIV controls lacking HS were selected randomly. In patients with severe HS, we found significantly higher values of body mass index (BMI), plasma viral load, serum glucose, alkaline phosphatase, triglycerides and low-density lipoprotein cholesterol, as well as significantly higher prevalence of diabetes, elevated alcohol consumption, lipohypertrophy and advanced liver fibrosis. Furthermore, a trend towards longer exposure to nucleoside analogues was noticed. In the multivariate analysis, only elevated alcohol consumption [odds ratio (OR) 7, P=0.013], lipohypertrophy (OR 5.3, P=0.008), plasma viral load (OR 2.1, P=0.02), BMI (OR 1.2, P=0.013) and serum glucose (OR 1.03, P=0.027) were significantly associated with severe HS. CONCLUSIONS: Severe HS in HIV-positive patients is associated with predisposing factors that are similar to those of HIV-negative individuals. However, its characteristic association with elevated plasma viral load might suggest a direct involvement of HIV in liver fat deposition. Therefore, the benefit of controlling HIV replication with antiretroviral therapy should be balanced against its effect of occasionally inducing metabolic abnormalities and lipodystrophy.

Level, phenotype and activation status of CD4+FoxP3+ regulatory T cells in patients chronically infected with human immunodeficiency virus and/or hepatitis C virus.

CD4(+) regulatory T (T(reg)) cells have been involved in impaired immunity and persistence of viral infections. Herein, we report the level, phenotype and activation status of T(reg) cells in patients chronically infected with human immunodeficiency virus (HIV) and/or hepatitis C virus (HCV). Expression of CD25, CD45RA, CD27, CD127 and CD38 was assessed on these cells using polychromatic flow cytometry in 20 healthy controls, 20 HIV-monoinfected, 20 HCV-monoinfected and 31 HIV/HCV-co-infected patients. T(reg) cells were defined as CD4(+)forkhead box P3 (FoxP3)(+). The percentage of T(reg) cells was increased significantly in HIV patients compared with controls. Moreover, there was a significant inverse correlation between CD4 counts and T(reg) cell levels. Fewer than 50% of T(reg) cells expressed CD25, with differences in terms of CD127 expression between CD25(+) and CD25((-)) T(reg) cells. CD4(+)Foxp3(+) T(reg) cells displayed predominantly a central memory phenotype (CD45RA(-)CD27(+)), without differences between patients and healthy controls. Activated T(reg) cells were increased in HIV patients, particularly considering the central memory subset. In summary, HIV infection, but not HCV, induces an up-regulation of highly activated T(reg) cells, which increases in parallel with CD4 depletion. Hypothetically, this might contribute to the accelerated course of HCV-related liver disease in HIV-immunosuppressed patients.

Liver cirrhosis in HIV-infected patients: prevalence, aetiology and clinical outcome.

Liver disease is frequently seen in HIV+ patients as a result of coinfection with hepatitis B (HBV) or C (HCV) viruses, alcohol abuse and/or exposure to hepatotoxic drugs. The aim of this study was to assess the prevalence of liver cirrhosis, its main causes and clinical presentation in HIV+ patients. Observational, cross-sectional, retrospective study of all HIV+ individuals followed at one reference HIV outpatient clinic in Madrid. Liver fibrosis was measured in all cases using transient elastometry (FibroScan). All 2168 HIV+ patients on regular follow-up (76% males, 46% injecting drug users) were successfully examined by FibroScan) between October 2004 and August 2006. Liver cirrhosis was recognized in 181 (overall prevalence, 8.3%), and the main aetiologies were HCV, 82.3%; HBV, 1.6%; dual HBV/HCV, 2.8%; and triple HBV/HCV/ hepatitis delta virus (HDV) infection, 6.6%. The prevalence of cirrhosis differed among patients with distinct chronic viral hepatitis: HCV, 19.2%; HBV, 6.1%; HBV/HCV, 41.7%; and HBV/HCV/HDV, 66.7%. In 12 patients with cirrhosis (6.7%), no definite aetiology was recognized. Overall, cirrhotics had lower mean CD4 counts than noncirrhotics (408 vs 528 cells/microL respectively; P = 0.02), despite similar proportion of subjects with undetectable viraemia on highly active antiretroviral therapy. Clinical manifestations of liver cirrhosis were: splenomegaly, 61.5%; oesophageal varices, 59.8%; ascites, 22.6%; encephalopathy, 12.1%; and variceal bleeding, 6.1%. Liver cirrhosis and hepatic decompensation events are relatively frequent in HIV+ individuals. Chronic HCV and alcohol abuse, but not chronic HBV, play a major role. Transient elastometry may allow the identification of a significant number of HIV+ individuals with asymptomatic liver cirrhosis.

Liver fibrosis on account of chronic hepatitis C is more severe in HIV-positive than HIV-negative patients despite antiretroviral therapy.

The recent availability of non-invasive tools to measure liver fibrosis has allowed examination of its extent and determination of predictors in all patients with chronic hepatitis C virus (HCV) infection. On the other hand, most information on hepatic fibrosis in HCV/human immunodeficiency virus (HIV)-coinfected patients has been derived from liver biopsies taken before highly active antiretroviral therapy (HAART) was widely available. All consecutive HCV patients with elevated aminotransferases seen during the last 3 years were evaluated and liver fibrosis measured using transient elastography (FibroScan) and biochemical indexes. Patients were split according to their HIV serostatus. A total of 656 (69.6%) HCV-monoinfected and 287 (30.4%) HIV/HCV-coinfected patients were assessed. Mean CD4 count of coinfected patients was 493 cells/muL and 88% were under HAART (mean time, 4.2 +/- 2.4 years). Advanced liver fibrosis or cirrhosis was recognized in 39% of the coinfected and 18% of the monoinfected patients (P < 0.005). A good correlation was found between FibroScan) and biochemical indexes [AST to platelet ratio index (r = 0.405, P < 0.0001), FIB-4 (r = 0.393, P < 0.0001) and Forns (r = 0.407, P < 0.0001)], regardless of the HIV status. In the multivariate analysis, age >45 years, body mass index (BMI) >25 kg/m(2), and HIV infection were independently associated with advanced liver fibrosis or cirrhosis. HIV/HCV-coinfected patients have more advanced liver fibrosis than HCV-monoinfected patients despite the immunologic benefit of HAART.

[Lumbago radiating to the right leg as a form of onset of multiple myeloma in a 33-year-old patient]. / Lumbalgia irradiada a pierna derecha como forma de debut de mieloma múltiple en un paciente de 33 años.

We present the case of a 33 year old man who consulted because a lumbago; a bone lesion was detected on a lumbosacral radiography, and finally was diagnosed of Multiple Myeloma. The illness, diagnosis and epidemiology are briefly analyzed, rebounding the rarity of its presentation in a young man.

Lumbalgia irradiada a pierna derecha como forma de debut de mieloma múltiple en un paciente de 33 años / Lumbalgia irradiated to left leg as the first presentation os a multiple myeloma in a 33 year old man

Se presenta el caso de un varón de 33 años que consulta por lumbalgia y a quien se detecta una lesión ósea en la radiografía lumbosacra, siendo finalmente diagnosticado de Mieloma Múltiple. Se comenta brevemente la enfermedad, su diagnóstico y su epidemiología, subrayando la rareza de su presentación en un joven (AU)

Physical rehabilitation has a positive effect on disability in multiple sclerosis patients.

BACKGROUND: Although physical rehabilitation is commonly administered to MS patients, its efficacy has not been established. OBJECTIVE: We assessed the efficacy of an inpatient physical rehabilitation program on impairment, disability, and quality of life of MS patients with a randomized, single-blind, controlled trial. METHODS: Fifty ambulatory MS patients were assigned to 3 weeks of inpatient physical rehabilitation (study treatment) or exercises performed at home (control treatment). Patients were evaluated at baseline and at 3, 9, and 15 weeks by a blinded examining physician. RESULTS: No changes in impairment occurred in either group, as measured by the Expanded Disability Status Scale. At the end of the intervention the study group improved significantly in disability, as assessed by the Functional Independence Measure (FIM) motor domain, compared with controls (p = 0.004), and the improvement persisted at 9 weeks (p = 0.001). The effect size statistic was usually large or moderate in all scale scores of the FIM motor domain at 3 weeks and moderate to fair thereafter. The study group also improved in overall health-related quality of life profile compared with controls; however, the difference was significant only for the mental composite score at 3 (p = 0.008) and 9 weeks (p = 0.001). CONCLUSIONS: Despite unchanging impairment, physical rehabilitation resulted in an improvement in disability and had a positive impact on mental components of health-related quality of life perception at 3 and 9 weeks.

Cocaine-induced liver injury in mice elicits specific changes in DNA ploidy and induces programmed death of hepatocytes.

Liver injury was induced by a single dose (60 mg/kg) of cocaine in male albino Swiss mice untreated or pretreated with phenobarbital (in drinking water 1 gm/L), for 5 days before cocaine administration. One parameter of liver injury, serum isocitrate dehydrogenase activity, showed sharp increases at 24 hr of cocaine treatment; we also noted decrease hepatic levels of ATP, GSH, cytochrome P-450 and NADPH/NADP+ ratio and increases in malondialdehyde concentration. Histopathological study of liver slices showed perivenous and periportal necrosis induced by cocaine in untreated mice and mice pretreated with phenobarbital, respectively. A regenerative postnecrotic response, which peaked at 48 hr, was demonstrated by the appearance of mitotic cells. Mitotic index analysis showed that proliferative cells appear to be unevenly distributed in the hepatic acinus and were mainly located in the vicinity of the damaged acinar region. Genomic DNA ploidy and the distribution of DNA in the phases of the cell cycle were studied in nuclei of isolated hepatocytes. At 12 hr of cocaine administration, both in untreated and phenobarbital-pretreated mice, the following changes were observed: a sharp decrease in tetraploid (4N) cells (40% to 17% and 25% to 6%, respectively) and octoploid (8N) cells (5% to 2% and 2% to 1%, respectively), together with the appearance of a hypodiploid population (13% and 31%, respectively). Hypodiploid population was characterized as apoptotic cells by detection of DNA fragmentation in agarose gel. These results suggest that a significant percentage of cell death induced by cocaine occurs by means of the apoptosis death program. Comparison of the initial values of DNA ploidy with those obtained at 7 days of cocaine administration showed remarkable increases in polyploid populations (4N and 8N) and a decrease in diploid cells (2N), indicating that the process of differentiation occurs when liver restores its functionality.

Serum magnesium and nerve conduction velocity in uraemic patients on chronic haemodialysis.

In 18 patients on regular haemodialysis treatment, the dialysate magnesium concentration (dMg) was lowered (from 0.5 to 0.25 mmol/litre) and the correlation between serum Mg level (sMg) and nerve conduction velocity was investigated before and one year after dMg variation, in order to ascertain whether hypermagnesaemia plays a role in the pathogenesis of peripheral neuropathy in patients on regular dialysis. The normalization of sMg (from 1.27 +/- SD 0.16 to 0.98 +/- 0.09 mmol/litre) did not result in any improvement in nerve conduction velocity, though such improvement has previously been reported; however, this discrepancy could be explained by the fact that sMg was not excessively high at the beginning of the study.

The use of separator isoelectric focusing in micro-ultrathin polyacrylamide gels in the characterization of some polymorphic proteins of forensic science significance.

The identification of phenotypes of erythrocyte acid phosphatase (EAP), esterase D (EsD), group specific component (Gc), and alpha-1-antitrypsin (PI) by separator isoelectric focusing in micro-ultrathin polyacrylamide gels (interelectrode distance: 45 mm) is described. The protein patterns obtained are compared favorably with the patterns seen by isoelectric focusing in conventional polyacrylamide gel dimensions (interelectrode distance: 110 to 120 mm). The technique described allows greater stability of pH gradients and is a fast and economic method.

Lymphocytoplasmapheresis in multiple sclerosis: one-year results in 6 patients.

6 patients with definite MS underwent lymphocytoplasmapheresis for one year. Clinical data, evoked potential recordings and peripheral blood lymphocyte helper/suppressor ratio were assessed before and after the treatment and were compared with those of a control group of 10 multiple sclerosis patients. Lymphocytoplasmapheresis did not significantly modify clinical and laboratory findings compared with the control group.