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Mesoporous bioactive glasses (MBGs) are bioceramics designed to induce bone tissue regeneration and very useful materials with the ability to act as drug delivery systems. MBGs can be implanted in contact with bone tissue in different ways, as particulate material, in 3D scaffolds or as nanospheres. In this work, we assessed the effects of particles of mesoporous bioactive glass MBG-75S and mesoporous nanospheres NanoMBG-75S on RAW 264.7 and J774A.1 macrophages, which present different sensitivity and are considered as ideal models for the study of innate immune response. After evaluating several cellular parameters (morphology, size, complexity, proliferation, cell cycle and intracellular content of reactive oxygen species), the action of MBG-75S particles and NanoMBG-75S on the polarization of these macrophages towards the pro-inflammatory (M1) or reparative (M2) phenotype was determined by the expression of specific M1 (CD80) and M2 (CD206, CD163) markers. We previously measured the adsorption of albumin and fibrinogen on MBG-75S particles and the production of pro-inflammatory cytokines as TNF-α and IL-6 by macrophages in response to these particles. This comparative study demonstrates that particles of mesoporous bioactive glass MBG-75S and mesoporous nanospheres NanoMBG-75S allow the appropriated development and function of RAW 264.7 and J774A.1 macrophages and do not induce polarization towards the M1 pro-inflammatory phenotype. Therefore, considering that these mesoporous biomaterials offer the possibility of loading drugs into their pores, the results obtained indicate their high potential for use as drug-delivery systems in bone repair and osteoporosis treatments without triggering an adverse inflammatory response.

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The objective of this study was to investigate the factors underlying the development of metabolic syndrome (MetS) in HIV-infected patients. Two hundred and sixty-six clinical cases were selected for a retrospective study. The sample was classified using the Adult Treatment Panel III guidelines and the identification of risk or protective factors associated with MetS evaluated via multivariate logistic or multinomial regressions. HIV-infected individuals diagnosed with MetS tend to be older, overweight, or obese (85% have a BMI ≥ 25), with a waist circumference > 90 cm (96.5 [88.8-105.5] cm, median [interquartile range]). Blood testing these individuals revealed high fasting levels of insulin (8.1 [5.8-21.6] pg/ml), glucose (98.0 [84.0-116.0] mg/dl), triglycerides (201.0 [142.0-267.3] mg/dl), and high-density lipoprotein cholesterol (36.5 [29.8-43.3] mg/dl) in addition with higher levels of inflammatory mediators such as high-sensitivity C-reactive protein (2.5 [1.0-4.9] mg/dl) and interleukin-6 (3.4 [2.8-3.8] pg/ml). The likelihood of HIV-infected individuals who are virally suppressed developing MetS is about 60% higher than those with acute infection. Treatment with nucleoside reverse transcriptase inhibitors (NRTIs) and protease inhibitors (PIs) increases the chance of developing MetS by around 2.4 times. Individuals with a lower antioxidant capacity (total antioxidant status [TAS] <1.33) have a 2.6 times higher risk of developing MetS. HIV-related chronic inflammation, a low TAS, and treatment with NRTIs in association with PIs are additional MetS risk factors.

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BACKGROUND: Colorectal cancer is the third most common and the third most lethal cancer in both men and women in developed countries. About 75% of cases are first diagnosed when the disease is classified as localized or regional, undergo potentially curative treatment and enter a post-treatment surveillance program. Although such programs drain significant resources from health systems, empirical evidence of their efficacy is scanty. PATIENTS AND METHODS: Dukes B2-C colorectal cancer patients who had no evidence of disease at the end of their front-line treatment (surgery and adjuvant radiochemotherapy, if indicated) were eligible for the trial and randomized to two different surveillance programs. These programs differed greatly in the frequency of diagnostic imaging. They had similar schedules of physical examinations and carcinoembryonic antigen (CEA) assessments. Patients received baseline and yearly health-related quality-of-life (HR-QoL) questionnaires. Primary outcomes were overall survival (OS) and QoL. RESULTS: From 1998 to 2006, 1228 assessable patients were randomized, 933 with colon cancer and 295 with rectal cancer. More than 90% of patients had the expected number of diagnostic procedures. Median follow-up duration was 62 months [interquartile range (IQR) 51-86] in the minimal surveillance group and 62 months (IQR 50-85) in the intensive group. At primary analysis, 250 patients had recurred and 218 had died. Intensive surveillance anticipated recurrence, as shown by a significant difference in mean disease-free survival of 5.9 months. Comparison of OS curves of the whole intention-to-treat population showed no statistically significant differences. HR-QoL of life scores did not differ between regimens. CONCLUSION: Our findings support the conclusions of other randomized clinical trials, which show that early diagnosis of cancer recurrence is not associated with OS benefit. CLINICALTRIALSGOV: NCT02409472.

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To study dysglycaemia in human immunodeficiency virus (HIV)-infected patients we conducted a retrospective cohort study of the glucose profile in HIV-infected patients. The fasting blood glucose was analysed taking into consideration conventional risk factors as well as HIV infection and highly active antiretroviral therapy (HAART). One hundred seventy-three cases were selected for this study. Five risk factors had significant effects (p < 0.05) on glucose levels: age, body mass index (BMI), hepatitis C virus/hepatitis B virus (HCV/HBV) co-infection, viral load (VL), and CD4(+) T-lymphocyte count. Fasting blood glucose levels increased with age (0.59 mg/dL/year), decreased with the VL (-4.1 × 10(-6 )mg/dL/number of viral RNA copies) and the CD4(+) T-lymphocyte count (-0.016 mg/dL/cell count). Furthermore, obese patients and those co-infected with HCV/HBV were more prone to develop dysglycaemia having, on average, 15.4 mg/dL and 13.8 mg/dL higher levels, respectively, of fasting blood glucose. Despite an increase of 1.0% and 8.4% in the glucose levels noticed among HIV patients treated with non-nucleotide inhibitors of reverse transcriptase and protease inhibitors, respectively, HAART did not prove to be a significant predictor of fasting glucose levels as well as lipodystrophy and male gender. Age, BMI, HCV/HBV co-infection and HIV-related (VL and CD4(+) T-lymphocyte count) factors seem to be the most influential on fasting blood glucose levels in HIV-infected individuals.

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Crohn's disease (CD) has been correlated with altered macrophage response to microorganisms. Considering the efficacy of infliximab treatment on CD remission, we investigated infliximab effects on circulating monocyte subsets and on macrophage cytokine response to bacteria. Human peripheral blood monocyte-derived macrophages were obtained from CD patients, treated or not with infliximab. Macrophages were infected with Escherichia coli, Enterococcus faecalis, Mycobacterium avium subsp. paratuberculosis (MAP) or M. avium subsp avium, and cytokine levels [tumour necrosis factor (TNF) and interleukin (IL)-10] were evaluated at different time-points. To evaluate infliximab-dependent effects on monocyte subsets, we studied CD14 and CD16 expression by peripheral blood monocytes before and after different infliximab administrations. We also investigated TNF secretion by macrophages obtained from CD16(+) and CD16(-) monocytes and the frequency of TNF(+) cells among CD16(+) and CD16(-) monocyte-derived macrophages from CD patients. Infliximab treatment resulted in elevated TNF and IL-10 macrophage response to bacteria. An infliximab-dependent increase in the frequency of circulating CD16(+) monocytes (particularly the CD14(++) CD16(+) subset) was also observed (before infliximab: 4·65 ± 0·58%; after three administrations: 10·68 ± 2·23%). In response to MAP infection, macrophages obtained from CD16(+) monocytes were higher TNF producers and CD16(+) macrophages from infliximab-treated CD patients showed increased frequency of TNF(+) cells. In conclusion, infliximab treatment increased the TNF production of CD macrophages in response to bacteria, which seemed to depend upon enrichment of CD16(+) circulating monocytes, particularly of the CD14(++) CD16(+) subset. Infliximab treatment of CD patients also resulted in increased macrophage IL-10 production in response to bacteria, suggesting an infliximab-induced shift to M2 macrophages.

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OBJECTIVE: Study of the lipid profile in patients infected with HIV treated with different combinations of high activity anti-retroviral therapy (HAART). DESIGN AND METHODS: A retrospective cohort study of the lipid profile in patients undergoing HAART. The study analyzes the evolution of concentrations of triglycerides (TG), total cholesterol (TC), LDL-cholesterol (LDLc) and HDL-cholesterol (HDLc) in a period of at least 3 years of treatment. From a total of 750 clinical cases analyzed in Hospital Joaquim Urbano (Oporto, Portugal) 124 patients were selected for this study. RESULTS: After 3 years of treatment, we observed the development of dyslipidaemia by increases in TG (17%), TC (29%) and LDLc (9%), particularly in patients treated with a combination of drugs which included protease inhibitors (PI). Moreover, the non-nucleoside reverse transcriptase inhibitors (NNRTI) were associated with better lipid profile. The increase of 46% in HDLc was the most surprising finding. CONCLUSIONS: The results indicate that patients with HAART have a more atherogenic lipidic profile with increased TC, LDLc and TG levels. Since the effectiveness of NNRTI is similar to that of PI, but with a smaller atherogenic profile, it should be the first choice drug to be selected in the HIV treatment.

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Congenital malaria, defined as the presence of malaria parasites in the erythrocytes of newborns aged <7 days, was considered rare in endemic areas until recent studies started reporting high prevalence rates. Various theories have been postulated to explain this phenomenon, but they are not proven conclusively from research. Against this background, a prospective study was designed with the following objectives. To determine the prevalence of congenital malaria parasitaemia and identify possible risk factors amongst newborns delivered in O.O.U.T.H Sagamu, Ogun State. Over a 6-month period, 192 live newborns and their mothers were consecutively recruited into the study. Within 3 days of life, neonatal peripheral blood samples were collected for malaria screening by blood film microscopy and detection of plasmodium lactate dehydrogenase (pLDH) with the OptiMAL Rapid Malaria Test kit. Maternal peripheral blood samples were taken simultaneously, to check for malaria infestation by blood film microscopy, and questionnaires were administered on the mothers to identify possible factors associated with the development of neonatal parasitaemia. Neonatal clinical and laboratory data were recorded in a pro forma designed for the study. Data analysis was done with Epi-info version 6 software and level of significance set at <5%. Twenty-one of 192 newborns delivered in O.O.U.T.H within the study period were diagnosed as having congenital malaria by blood film microscopy, giving a prevalence rate of 10.9%. The main identified innate neonatal risk factor for congenital malaria parasitaemia was prematurity. First-order pregnancy, history of fever within 3 months of delivery and peripheral parasitaemia at delivery (p < 0.001) were the variables that were significantly higher in the mothers of the parasitemic newborns. We conclude that congenital malaria parasitaemia in tropical endemic areas is not rare. Pre-term neonates, infants of primigravidae, women with history of fever within 3 months of delivery and women with post-partum peripheral parasitaemia may benefit from routine screening for malaria.

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OBJECTIVE: To assess the performance of OptiMAL, a rapid malaria antigen capture dipstick, in diagnosing congenital malaria. METHODS: Live newborns aged 0-3 days, delivered at Olabisi Onabanjo University Teaching Hospital, Sagamu, Nigeria between August 2004 and January 2005, were screened for malaria parasitaemia with an immunochromatographic test (OptiMAL) and blood film microscopy. OptiMAL detects plasmodium lactate dehydrogenase (pLDH). RESULTS: Twenty-one of 192 newborns (10.9%) were diagnosed with congenital malaria by blood film microscopy. The OptiMAL test was negative in all infants. CONCLUSION: OptiMAL rapid malaria antigen capture dipstick might not be useful for diagnosing malaria parasitaemia in newborns. Blood film microscopy remains the gold standard for the diagnosis of congenital malaria.

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BACKGROUND: Recent guidelines do not recommend antithrombotic prophylaxis (AP) to prevent catheter-related thrombosis in cancer patients with a central line. PATIENTS AND METHODS: This study assessed the management of central lines in cancer patients, current attitude towards AP, catheter-related and systemic venous thromboses, and survival. RESULTS: Of 1410 patients enrolled, 1390 were seen at least once in the 6-month median follow-up. Continuous AP, mainly low-dose warfarin, was given to 451 (32.4%); they were older, with a more frequent history of venous thromboembolism (VTE), and more advanced cancer. There was no difference in catheter-related thrombosis in patients given AP or not (2.8% and 2.2%, odds ratio 1.29, 95% confidence interval 0.64-2.6). The median time to first catheter-related complication was 120 days. Systemic VTE including deep and superficial thromboses and pulmonary embolism, were less frequent with AP (4% versus 8.2%, P = 0.005). Mortality was also lower (25% versus 44%, P = 0.0001). Multiple logistic regression analysis found only advanced cancer and no AP significantly associated with mortality. No major bleeding was recorded with AP. CONCLUSIONS: Current AP schedules do not appear to prevent catheter-related thrombosis. Systemic VTE and mortality, however, appeared lower after prophylaxis.

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The prevalence, causes, and consequences of energy-protein malnutrition (EPM) are reviewed in cirrhosis and its treatment, with special emphasis on those aspects that can be carried out in the ambulatory regime. EPM is a highly prevalent situation in advanced cirrhosis, but it probably already occurs in early stages of the disease. EPM has an important prognosis in cirrhosis. Specifically, the nutritional status could be a better predictor of the evolution after a liver transplant than the conventional prognostic indicators. The increase in the oxidation of fats and proteins is the most important mechanisms in EPM in these patients. The hypermetabolism and the deficit in ingestion are also relevant factors in the EPM in cirrhosis. Conventional diet therapy is the most important tool in the long term nutritional treatment in cirrhosis. The administration of nightly carbohydrate supplements could partially revert the alteration in the oxidation of the energetic substrates in these patients. Also, oral supplements of chemically defined diets could improve the quality of life and the long term survival of these patients. When artificial nutrition is indicated, enteral nutrition is the modality of choice in these patients. Enteral nutrition in cirrhosis is safe, nutritionally effective (as it guarantees an adequate energetic-proteineic ingestion), and in some studies it has been associated with a better short term survival. Adding branched chain amino acids to the diets or enteral supplements meant for cirrhotics would only be essential in patients who show intolerance to the conventional protein. Other changes in the components of the diet formulae meant for cirrhotics are open to further research.

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Energy-protein malnutrition and the sub-clinical deficiencies of vitamins and trace elements, are frequent findings in ulcerative colitis and Crohn's disease, and these may negatively influence the clinical course of these diseases. In general, the majority of the patients with ulcerative colitis and uncomplicated Crohn's disease can ingest a normal diet that is well balanced and without any restrictions. The intolerance to specific foods is rare in Crohn's disease and the application of exclusion diets in a routine manner is not indicated. When the nutritional status cannot be adequately maintained with normal ingestion, the use of artificial nutrition is indicated. Enteral nutrition is the first choice nutritional support system if the gastrointestinal tract is accessible and at least partially functional. In Crohn's disease enteral nutrition could have a specific anti-inflammatory effect ("primary treatment"), and it has been suggested that this could be effective to induce the clinical remission of the activity bouts of the disease. Some types of dietary fiber could be effective in the treatment of ulcerative colitis. Initial studies suggest their usefulness in maintaining the remission of the disease.

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BACKGROUND: Although leucovorin (LV) + 5-fluorouracil (5-FU) is considered the treatment of choice for advanced colorectal cancer in most countries, the optimal schedule of this combination has not yet been established. Low-dose LV appears to be as active as high-dose LV in the daily-times-five regimen, but no randomized study of the levorotatory stereoisomer (6S-LV) given at two different dose levels has been published. PATIENTS AND METHODS: Between November 1991 and June 1994, 422 patients (all with measurable disease previously untreated with chemotherapy) were randomized to 6S-LV (100 mg/sqm/i.v.) + 5-FU (370 mg sqm/15 min i.v. infusion), both administered for 5 days every 28 days (arm A), or to 6S-LV (10 mg/sqm/i.v./5-FU (doses as above), also given for 5 days every 28 days (arm B). The primary endpoint of the study was the comparison of response rates (WHO criteria): the secondary endpoint was the assessment of survival and tolerability. No evaluation of the quality of life or the symptomatic effect of treatment was planned. RESULTS: The response rate was 9.3% in arm A (95% CI: 5.4-13.1), with 2 CR and 18 PR, and 10.7% in arm B (95% CI: 6.5-14.9), with 3 CR + 19 PR, without any significant difference (P = 0.78). The median time to progression was eight months in both groups and overall survival was 11 months, with no difference between treatments. Toxicity mainly consisted of gastrointestinal side effects (mucositis and diarrhoea), which were rarely severe (grade 3-4: 5%-10% of patients) and similar in the two groups. CONCLUSIONS: In this large-scale multicentre trial, the low and high doses of 6S-LV appeared to be equivalent in terms of the biochemical modulation of 5-FU in advanced colorectal cancer although, for several reasons (including the timing and the strict criteria of response evaluation, the high number of patients with unfavourable prognostic factors, the multi-institutional nature of the study, the dose and modality of 5-FU administration), the response rate was lower than that reported in some of the other published studies. Given the considerable difference in economic cost between the two dosages, the use of high-dose 6S-LV in the daily-times-five regimen is not recommended in clinical practice.

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In advanced colorectal cancer the addition of folinic acid (FA) has been shown to lead to increased activity, at least in terms of response rate, in comparison with 5-fluorouracil (5FU) alone. Similarly, interferon-alpha (IFN) is able to potentiate 5FU, although high doses cause heavy toxicity. Given the different mechanisms of action of the two agents, the double modulation of 5FU deserves clinical evaluation. In a multicenter study (involving both primary care and referral institutions) 63 patients with advanced colorectal cancer, previously untreated with chemotherapy, received, in an outpatient setting, FA (200 mg/m2 i.v. bolus) + 5FU (400 mg/m2 i.v. in 15 min) for 5 consecutive days every 4 weeks + IFN 3 x 10(6) U on alternate days, starting 1 week before chemotherapy. During the 5 days of 5FU + FA, IFN was administered daily. The antitumour activity, the impact on response duration and survival and toxicity of the combination were evaluated according to WHO criteria. Of the 63 enrolled patients, 56 were evaluable: there were 2 complete responses (3%) and 13 partial responses (21%), giving an objective response rate of 24% (95% confidence interval 13-35%); no change was observed in 17 cases and progressive disease in 24. Median duration of response was 9 months and median survival (all patients) 13 months. Toxicity was acceptable, even though 4 patients presented reversible grade 4 side-effects (2 mucositis and 2 diarrhoea). With this schedule and these doses, addition of IFN did not lead to any increase in the activity of 5FU + FA. In colorectal cancer, further clinical studies with these drugs should be based on a deeper experimental knowledge of their mechanisms of interaction.

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Plasma membrane fractions from normal, regenerating liver and the AS-30D ascites hepatocarcinoma exhibited a high degree of enrichment when a set of plasma membrane enzyme markers were studied in comparison to the ones associated to the mitochondrial and cytosolic compartments. While the (Ca2+, Mg2+)-ATPase observed for the plasma membrane fraction isolated from normal liver showed an activity of 1.2 mumoles/mg/min, the regenerating liver and the AS-30D plasma membrane fractions presented a much lower ATPase activity (0.3 and 0.22 mumoles/mg/min respectively). Despite the differences in ATPase activity observed between models, the plasma membrane fraction from the AS-30D hepatocarcinoma presented a calcium transport activity similar to the value observed for the normal system (5.9 and 5.5 nmoles Ca2+/mg/10 min, respectively). Interestingly, the ATP in equilibrium with Pi exchange experiments carried out with the different plasma membrane fractions revealed that the (Ca2+, Mg2+)-ATPase contained in the plasma membrane from the AS-30D cells shows an exchange activity of 26 nmoles ATP in equilibrium with Pi/mg/min, similar to the one observed fo the enzyme from normal liver (30 nmoles ATP in equilibrium with Pi/mg/min). Our results suggest that the plasma membrane from the transformed model presents a more efficient mechanism to regulate the movement of calcium through the calcium pump, with an optimum expenditure of energy.

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An updated revision has been made of the relevant nutritional and metabolic aspects of the so-called critical patient or of the patient exposed to aggressive measures. The different factors and circumstances that coincide in a situation of multiorgan failure in this type of patient have been assessed. The importance of the GI tract (Gut Hypothesis) and malnutrition has been underscored, both as the origin of Multisystemic Failure and in the application of possible therapeutic measures. A special point has been made on the importance of sustaining small bowel function, and on the adaptation mechanisms regarding the controversy on the use of enteral nutrition in these situations.

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