Polyunsaturated fatty acids and inflammatory diseases

Inflammation is overall a protective response, whose main goal is to liberate the human being of cellular lesions caused by micro-organisms, toxins, allergens, etc., as well as its consequences, and of death cells and necrotic tissues. Chronic inflammation, which is detrimental to tissues, is the basic pathogenic mechanism of hypersensitivity reactions against xenobiotics. Other frequent pathologies, for instance atherosclerosis, chronic hepatitis, inflammatory bowel disease (IBD), liver cirrhosis, lung fibrosis, psoriasis, and rheumatoid arthritis are also chronic inflammatory diseases. Chemical mediators of inflammation are derived from blood plasma or different cell-type activity. Biogenic amines, eicosanoids and cytokines are within the most important mediators of inflammatory processes. The different activities of eicosanoids derived from arachidonic acid (20:4 n-6) versus those derived from eicosapentaenoic acid (20:5 n-3) are one of the most important mechanisms to explain why n-3, or omega-3, polyunsaturated fatty acids (PUFA) exhibit anti-inflammatory properties in many inflammatory diseases. Dietary supplements ranging 1-8 g per day of n-3 PUFA have been reportedly beneficial in the treatment of IBD, eczema, psoriasis and rheumatoid arthritis. In addition, recent experimental studies in rats with experimental ulcerative colitis, induced by intrarectal injection of trinitrobenzene sulphonic acid, have documented that treatment with n-3 long-chain PUFA reduces mucosal damage as assessed by biochemical and histological markers of inflammation. Moreover, the defence antioxidant system in this model is enhanced in treated animals, provided that the n-3 PUFA supply is adequately preserved from oxidation.

Modulation of the immune response mediated by dietary nucleotides

Dietary nucleotides have been reportedly beneficial, especially for infants, since they positively influence lipid metabolism, immunity, and tissue growth, development and repair. Rapidly proliferating tissues, such as the immune system or the intestine are not able to fulfil the needs of cell nucleotides exclusively by de novo synthesis and they preferentially utilize the salvage pathway recovering nucleosides and nucleobases from blood and diet. In the present review we describe the modulatory effect of dietary nucleotides on the immune system together with some of their effects on gut-associated lymphoid tissue. Dietary nucleotides influence lymphocyte maturation, activation and proliferation. Likewise, they affect the lymphocyte subset populations in both the small intestine and blood. Moreover, they are involved in enhancing macrophage phagocytosis and delayed hypersensitivity as well as allograft and tumour responses. In addition, they contribute to the immunoglobulin response in early life, having a positive effect on infection. In fact the incidence and duration of acute diarrhoea is lower in infants fed supplemented-nucleotide formulas. The molecular mechanisms by which dietary nucleotides modulate the immune system are practically unknown. Dietary nucleotides have been shown to enhance the production and the genetic expression of IL-6 and IL-8 by foetal small intestinal explants. Dietary nucleotides may influence protein biosynthesis as well as signal membrane transduction mediated by the interaction of exogenous nucleosides and their receptors may also contribute to modulate the expression of a number of genes, some of which can directly affect the levels of intestinal cytokines.

Serum selenium and risk of large size colorectal adenomas in a geographical area with a low selenium status

OBJECTIVE

Selenium is a fundamental nutrient to human health that might have anticarcinogenic effects. Previous studies have assessed the possible relationship of selenium status to colorectal adenomas with controversial results. We primarily aimed to assess the relationship of serum selenium status with the presence of large size colorectal adenomas in subjects living in a poor selenium region. The serum selenium status in colorectal cancer was also evaluated.

METHODS

Serum selenium levels were measured in 28 patients with large size sporadic adenomatous polyps, 24 patients with colorectal adenocarcinomas, and 35 age-matched healthy individuals. A logistic regression analysis was performed to assess the relationship of serum selenium to colorectal adenomatous polyps after adjusting for confounding variables (age, sex, smoking habit, and alcohol drinking).

RESULTS

Among subjects aged < or = 60 yr, mean serum selenium levels were significantly lower in both patient groups (adenoma, 57.9 +/- 4.3 microg/L; cancer, 43.7 +/- 6.6 microg/L) than in healthy controls (88.9 +/- 8 microg/L) (p = 0.0001). There were no difference among subjects > 60 yr old. A significant inverse association between selenium status and the diagnosis of large size adenomatous polyps after adjusting for confounding variables was found (adjusted p = 0.029). Subjects with higher selenium status (> or = 75th percentile value of 82.11 microg/L) had a lower probability (OR = 0.17, 95% CI = 0.03-0.84) to be in the adenoma group than subjects with lower selenium status (< 82.11 microg/L). This association was more marked in subjects aged < or = 60 yr (adjusted p value = 0.04, OR = 0.08, 95% CI = 0.007-0.91), and was not significant in older subjects.

CONCLUSIONS

Results suggest that high selenium status may decrease the risk of large size adenomas in a low selenium region, and that this preventive effect seems to be exclusive to subjects < or = 60 yr. These results will need to be confirmed in additional epidemiological studies before recommending selenium supplementation in patients with colon adenomas.

Long-chain polyunsaturated fatty acids (LC-PUFA) during early development: contribution of milk LC-PUFA to accretion rates varies among organs

Long-chain polyunsaturated fatty acids (LC-PUFA) accretion (essential for growth and neural development) was studied from late fetal throughout weaning age in the ferret, a species with maternal LC-PUFA sufficiency during pregnancy and lactation. The data show that a) accretion rate of LC-PUFA is rapid during early postnatal development, b) milk LC-PUFA decrease during lactation, c) adipose tissue LC-PUFA level is directly related to milk LC-PUFA level, while accretion in brain and liver exceeds dietary intake, d) accretion of arachidonic acid occurs earlier than docosahexaenoic acid, suggesting earlier development of n6-fatty acid endogenous synthesis.

Surface Pressure–Area Isotherms and Fluorescent Behavior of Phospholipids Containing Labeled Pyrene

In this work, the surface and fluorescent behavior of three phospholipids containing a pyrene molecule in one of their hydrocarbon chains was studied. Differences between the isotherms provided by the different monolayers can be attributed to the orientation of the head group in the phospholipids at the air/water interface. This assertion is supported by the fluorescent behavior of monolayers of phospholipids containing labeled pyrene (Py-DPPE, Py-DPPC, and Py-DPPG).

Sunflower, virgin-olive and fish oils differentially affect the progression of aortic lesions in rabbits with experimental atherosclerosis

In this study we report the effects of sunflower, virgin olive and fish oils on the progression of aortic lesions. A total of 24 male New Zealand rabbits (six per each group) were fed for 50 days on a diet containing 3% lard and 1.3% cholesterol, to induce atherosclerosis. An atherogenic control group (A) was killed after this period and three groups were fed for an additional period of 30 days with a diet composed of (1.75 g of supplemented oil and 98.25 of standard chow): sunflower oil (S), virgin olive oil (O) and fish oil (F). A control group (n=6) was fed with a standard chow diet for 80 days. LDL lipid composition and histological analysis of aortic atherosclerotic lesions were assayed. The atherogenic diet caused a significant increase of cholesterol levels in LDL and aorta tissue. Cholesterol ester content rose significantly in the aortic arch of groups S, O and F. Fatty streaks were found in all aortic sections, although only group S showed a significant progression of the lesion compared with group A. We conclude that the replacement of a high cholesterol-saturated fat diet by another cholesterol free-unsaturated fat diet does not regress atherosclerosis in rabbit. However, sunflower oil provokes a significant progression in lesion development, whereas diet enrichment with extra virgin olive oil and, to a lesser extent, fish oil, stops this progression.

Modifications in the C terminus of the synaptosome-associated protein of 25 kDa (SNAP-25) and in the complementary region of synaptobrevin affect the final steps of exocytosis

Fusion proteins made of green fluorescent protein coupled to SNAP-25 or synaptobrevin were overexpressed in bovine chromaffin cells in order to study the role of critical protein domains in exocytosis. Point mutations in the C-terminal domain of SNAP-25 (K201E and L203E) produced a marked inhibition of secretion, whereas single (Q174K, Q53K) and double mutants (Q174K/Q53K) of amino acids from the so-called zero layer only produced a moderate alteration in secretion. The importance of the SNAP-25 C-terminal domain in exocytosis was also confirmed by the similar effect on secretion of mutations in analogous residues of synaptobrevin (A82D, L84E). The effects on the initial rate and magnitude of secretion correlated with the alteration of single vesicle fusion kinetics since the amperometric spikes from cells expressing SNAP-25 L203E and K201E and synaptobrevin A82D and L84E mutants had lower amplitudes and larger half-width values than the ones from controls, suggesting slower neurotransmitter release kinetics than that found in cells expressing the wild-type proteins or zero layer mutants of SNAP-25. We conclude that a small domain of the SNAP-25 C terminus and its counterpart in synaptobrevin play an essential role in the final membrane fusion step of exocytosis.

Epidemiology of pneumonia hospitalizations in Spain, 1995-1998

OBJECTIVES

This epidemiological survey was undertaken to estimate the burden of hospital admissions for pneumonia in Spain during a four-year period (1995-1998).

METHODS

Data were obtained from the national surveillance system for hospital data.

RESULTS

There were 231,512 hospital admissions for pneumonia (ICD 9 CM 480-486; first listed diagnosis) during this period, that is an annual incidence of 177 cases per 100,000 population. The incidence was higher in children <5 years of age and in persons >or=65 years compared with other age groups. The annual cost of these hospitalizations to the National Health Care System was of 127 million ECUS.

CONCLUSIONS

Preventive measures, such as vaccination of population groups at high risk, to reduce pneumonia-related morbidity could result in large cost savings to the National Health Care System.

Budesonide enema in pouchitis--a double-blind, double-dummy, controlled trial

BACKGROUND

Pouchitis has been suggested to be a recurrence of ulcerative colitis in a colon-like mucosa. Topical steroids are a valid therapeutic alternative for distal forms of ulcerative colitis.

AIM

To investigate the efficacy and tolerability of budesonide enema in the treatment of pouchitis compared with oral metronidazole.

MATERIALS AND METHODS

Twenty-six patients with an active episode of pouchitis (defined as a pouchitis disease activity index score >or= 7) and no treatment during the previous month were randomized to receive either budesonide enema (2 mg/100 mL at bedtime) plus placebo tablets or oral metronidazole (0.5 g b.d.) plus placebo enema in a prospective, double-blind, double-dummy, 6-week, controlled trial.

RESULTS

Based on the intention-to-treat principle, we detected a significant improvement in disease activity at the end of the first week with both drugs (P < 0.01). After that, improvement was moderated until stabilization at 4 weeks in both treatments. The per protocol analysis showed that both drugs had similar efficacy in terms of disease activity, clinical and endoscopic findings. Fifty-eight per cent and 50% of patients improved (decrease in pouchitis disease activity index >or= 3) with budesonide enema and metronidazole, respectively (odds ratio, 1.4; confidence interval, 0.2-8.9). Adverse effects were observed in 57% of patients given metronidazole and in 25% of patients given budesonide.

CONCLUSIONS

Budesonide enemas are an alternative treatment for active pouchitis, with similar efficacy but better tolerability than oral metronidazole.

Nucleotides as semiessential nutritional components

Dietary nucleotides are required nutrients for some tissues under certain circumstances. A lack of dietary nucleotides negatively influences protein synthesis in both the liver and the small intestine of rats. Ribosome degradation has been observed as being among the mechanisms responsible for this effect. Dietary nucleotides can also modulate gene expression by interaction with specific transcription factors, in both the liver and the small intestine.

Fortified foods. Criteria for vitamin supplementation in Spain

OBJECTIVE

To review and analyse criteria for vitamin supplementation and fortification in Spain.

DESIGN

Systematic review of scientific literature and simulation analysis of food fortification.

METHODS

A simulation analysis using a fortified beverage was performed in a random sample of 2855 children aged 2 to 24 years in Spain.

RESULTS

High-risk groups for vitamin supplementation and fortification in Spain are highlighted, and target vitamins considered have been: folic acid, vitamin A, vitamin E, vitamin D and vitamin B12 (particularly in the elderly). A beverage fortified with vitamins C, A, B1 and B6 may contribute to improving the intake of all of these vitamins with the exception of vitamin A, since the Recommended Nutrient Intake is already covered with current consumption.

CONCLUSIONS

A detailed knowledge of nutritional status helps to ensure the rationale and follow up of nutrient supplementation and fortification.

Erectile dysfunction in a primary care setting: results of an observational, no-control-group, prospective study with sildenafil under routine conditions of use

In order to assess the effectiveness of sildenafil under routine conditions of use in primary care settings and to evaluate its impact on patient's life satisfaction and partner's satisfaction with treatment for erectile dysfunction (ED), an open, multicentre, observational, prospective study was designed in which 2816 patients were treated with sildenafil for at least 10 weeks. Effectiveness was assessed using the International Index of Erectile Dysfunction (IIEF), life satisfaction was measured with 'Life-satisfaction Check List' (LISAT 8), and EDITS was optionally used to assess the partner's satisfaction with ED therapy. Sildenafil was effective in 86.6% of patients. All dimensions of IIEF significantly increased with sildenafil, particularly erectile domain which overall sample mean score improved was 13.2 points (P < 0.001). The greatest increases in satisfaction with all aspects of life were seen in sex life and relationship with partner dimensions. The patients' partners, answered by a minority of partners, were highly satisfied with the treatment and its rapid action, therefore they were in favour of continuing with same. The adverse events occurring were similar to those seen in clinical research on sildenafil in the premarketing phase. No control group was included in this study.

Dietary long-chain polyunsaturated fatty acids from different sources affect fat and fatty acid excretions in rats

Several sources of long-chain polyunsaturated fatty acids (LCP) have been evaluated for infant-formula supplementation. These sources differ in their chemical structure [triglyceride (TG) or phospholipid (PL)], arrangement of fatty acids on the TG or PL backbone, fatty acid composition and presence of other lipid components. All of these characteristics influence fat digestion, may affect fat and fatty acid absorption, and hence, LCP bioavailability and metabolism in infancy. The main objective of this work was to establish the influence of different dietary LCP sources on overall fat and LCP absorption in early life. We compared fat and fatty acid excretions at weaning in rats fed control diets or diets supplemented with LCP as TG or PL. Two separate experiments were conducted. In Experiment 1, weanling rats were fed for 3 wk a control diet (C1), a diet with TG from tuna and fungal oils (TF-TG) or a diet with PL from pig brain concentrate (PB-PL). In Experiment 2, weanling rats were fed for 3 wk a control diet (C2), a diet containing egg-TG (EG-TG) or a diet containing egg-PL (EG-PL). Fat, mineral and saturated fatty acid excretions in feces were higher in rats fed PB-PL compared with those fed TF-TG diet. In Experiment 2, groups did not differ in fat and mineral excretions. However, the EG-PL group had lower fecal excretions of saturated fatty acids than the C2 and EG-TG groups. The 16:1(n-7), 18:1(n-9), 18:2(n-6) and 22:6(n-3) levels in feces were higher in the EG-TG group than in the EG-PL group. In summary, total fat and LCP excretions differed among rats fed diets supplemented with LCP from different sources.

Epidemiology of primary varicella hospitalizations in Spain

An approach to the burden of varicella can be obtained from information on the hospitalizations. Data were obtained from the national surveillance system for hospital data. All hospital discharges for varicella were analyzed for the 1995-1998 period. A total of 3632 primary varicella-related discharges were identified, representing an annual incidence of 2.8 per 100,000 population. A total of 58% of cases were <10 years of age and 33% were 21-50 years old. Each year primary varicella will be responsible for 6174 days of hospitalization, representing an annual cost of 1.6 million euros. There is substantial severe morbidity each year from varicella that, to reduce, would require vaccination of infants and susceptible adults.

Absorption and distribution of dietary fatty acids from different sources

Lipids have physical, chemical, and physiological properties that make them important factors in human nutrition. They form a group of compounds of varied chemical nature that have the common property of being soluble in organic solvents but insoluble in water. This basic property affects their digestion, absorption, and transport in the blood and metabolism at cellular level. Firstly, fatty-acid chain length and number of double bonds influence fat absorption. Thus, medium-chain fatty acids (MCFA) are better absorbed than long-chain fatty acids. Secondly, the positional distribution of fatty acids (FA) in dietary triglycerides (TG) determine whether FA are absorbed as 2-monoglycerides (2-MG) or free fatty acids (FFA), and hence, influences the composition of chylomicroms (CM) because triglycerides (TG) are resyntethysed in the intestinal mucosa using 2-MG from dietary lipids. Generally, the absorption of FA in the sn-2 position of TG is favored, whereas no specificity has been found for the fatty acids in the sn-1 and sn-3 positions. Finally, some FA of nutritional interest, namely, long-chain polyunsaturated fatty acids (LCP), are present in dietary lipid sources as both TG or phospholipids (PL). Fatty acids esterified as PL or TG may show different availability. In fact, some authors have suggested a better absorption of LCP-PL. Moreover, dietary LCP in form of TG or PL differently affects the composition of HDL and LDL PL.

Dietary trans fatty acids in early life: a review

Trans fatty acids are unsaturated fatty acids with at least a double trans configuration, resulting in a more rigid molecule close to a saturated fatty acid. These appear in dairy fat because of ruminal activity, and in hydrogenated oils; margarines, shortenings and baked goods contain relatively high levels of trans fatty acids. These fatty acids can be incorporated into both fetal and adult tissues, although the transfer rate through the placenta continues to be a contradictory subject. In preterm infants and healthy term babies, trans isomers have been inversely correlated to infantile birth weight. However, in multigenerational studies using animals, there is no correlation between birth weight, growth, and dietary trans fatty acids. Maternal milk reflects precisely the daily dietary intake of trans fatty acids, from 2% to 5% of the total fatty acids in human milk. The level of linoleic acid in human milk is increased by a high trans diet, but long-chain polyunsaturated fatty acids remain mostly unaffected. Likewise, infant tissues incorporate trans fatty acids from maternal milk, raising the level of linoleic acid and relatively decreasing arachidonic and docosahexaenoic acids. This suggests an inhibitory effect of trans fatty acid on liver Delta-6 fatty-acid desaturase activity. As opposed to blood and liver, the brain appears to be protected from the trans fatty-acid accumulation in experimental animals, but no data have yet been reported for human newborns. Further investigations in humans are needed to definitively establish the potential physiological consequences of trans fatty-acid intake during the neonatal period.

The influence of dietary nucleotides on humoral and cell immunity in the neonate and lactating infant

The organism constantly requires nucleotides, especially for tissues that present a high rate of turnover, such as the cells of the immune system. In certain circumstances, nucleotides may become semi-essential nutrients required by a particular organ. There is evidence of the potential role of exogenous nucleotides as regulators of the immune function. In experiments carried out with animals, studies have shown that dietary nucleotides stimulate the humoral immune response to T-dependent antigens and raise total antibody levels. The present study reveals an increase in the production of immunoglobulins, an improved response to vaccines, a reduction in morbidity and increased tolerance to dietary antigens. Therefore, the addition of nucleotides to formula appears to favour the immune function.

Analysis of 31 CFTR mutations in 55 families from the South of Spain

We carried out a molecular analysis of 350 chromosomes from 55 families originating from the South of Spain (Andalucia) who were diagnosed with cystic fibrosis (CF). We used polymerase chain reaction, followed by an oligonucleotide ligation assay (OLA) and sequence-coded separation using capillary electrophoresis. A frequency of 43.5% for DeltaF508 was found, making it the most common CF mutation in our sample. Seven more mutations (G542X, R334W, R1162X, 2789+5G-->A, R117H, DeltaI507 and W1282X) were detected and accounted for 24.7% of the total. The remaining mutations (31.8%) were undetectable with the methodology used in this study.

Hospital admissions for pertussis in Spain, 1995-1998

This epidemiological survey was undertaken to estimate the annual burden of hospitalizations for pertussis in Spain during a four-year period 1995-1998. Data were obtained from the national surveillance system for hospital data. All hospital discharges for pertussis (ICD-9- CM 033) were analyzed. The annual incidence of hospitalization for pertussis was 1.7 per 100,000 population. Eighty-nine percent of the cases were < 1 year of age (incidence of 78 per 100,000) and 95% were < or =5 years of age (incidence of 28 per 100,000). During the study period, 14 deaths were reported among patients hospitalized by pertussis. Despite of the high immunization rates, many pertussis cases occur each year, mostly of them among very young children.

Crude protein fractions in common vetch (Vicia sativa L.) fresh forage during pod filling

Crude protein (CP) of forages can be separated into fractions of differentiated abilities to provide available amino acids in the lower gut of ruminants. This knowledge is critical to develop feeding systems and to predict animal responses. We have measured during two growing seasons (1996 to 1997 and 1997 to 1998) the CP fractions of common vetch fresh forage with the objective being to assess the influence of maturity on concentration of CP fractions (as a percentage of total CP) and fraction yields. Fraction B2, which represents true protein of intermediate ruminal degradation rate, was the largest single fraction in common vetch forage (about 40% of CP across seasons and maturity stages). Soluble fractions (A plus B1) were less than 50% of total CP while the unavailable fraction C ranged from 4 to 8% of total CP. As a result, the remaining fraction B3 (true protein of very low degradation rate) only represented 2 to 9% of total CP. Concentration and yield of fraction B3 increased (P < 0.05) from flowering to pod-filling. Results showed that undegraded dietary protein represented a small proportion of total CP in common vetch forage. Moving the harvesting stage from flowering to the pod filling phase allowed for greater yield of undegraded dietary protein.

Vesicouterine fistula after vacuum delivery and two previous cesarean sections. A case report

BACKGROUND

Vesicouterine fistulas are associated with cesarean section and more rarely with vaginal birth after cesarean (VBAC). Many surgical approaches exist, including hysterectomy.

CASE

A vesicouterine fistula was diagnosed after VBAC in a 34-year-old multipara with two previous cesarean sections. The defect failed to close after four months of bladder drainage. Closure via laparotomy with an omental flap and preservation of the uterus was successful.

CONCLUSION

Vesicouterine fistula can occur after VBAC, and failure of conservative therapy can be treated abdominally with preservation of the uterus.