Nutritional composition of ultra-processed plant-based foods in the out-of-home environment: a multi-country survey with plant-based burgers

Ultra-processed plant-based foods, such as plant-based burgers, have gained in popularity. Particularly in the out-of-home (OOH) environment, evidence regarding their nutritional profile and environmental sustainability is still evolving. Plant-based burgers available at selected OOH sites were randomly sampled in Amsterdam, Copenhagen, Lisbon and London. Plant-based burgers (patty, bread and condiment) (n 41) were lab analysed for their energy, macronutrients, amino acids and minerals content per 100 g and serving and were compared with reference values. For the plant-based burgers, the median values per 100 g were 234 kcal, 20·8 g carbohydrates, 3·5 g dietary fibre and 12·0 g fat, including 0·08 g TFS and 2·2 g SFA. Protein content was 8·9 g/100 g, with low protein quality according to amino acid composition. Median Na content was 389 mg/100 g, equivalent to 1 g salt. Compared with references, the median serving provided 31% of energy intake based on a 2000 kcal per day and contributed to carbohydrates (17-28%), dietary fibre (42%), protein (40%), total fat (48%), SFA (26%) and Na (54%). One serving provided 15-23% of the reference values for Ca, K and Mg, while higher contributions were found for Zn, Mn, P and Fe (30-67%). The ultra-processed plant-based burgers provide protein, dietary fibre and essential minerals and contain relatively high levels of energy, Na and total fats. The amino acid composition indicated low protein quality. The multifaceted nutritional profile of plant-based burgers highlights the need for manufacturers to implement improvements to better support healthy dietary habits, including reducing energy, Na and total fats.

Sentinel Lymph Node Identification in Breast Cancer: Feasibility Study

The aim of the study was to evaluate in our institute the technique of sentinel node (SN) identification and biopsy in the surgical treatment of early breast cancer. Between June 1998 and November 1999 54 patients (age range, 31–75 years) where studied. Inclusion criteria were age less than 75 years, indication for conservative surgery, absence of palpable axillary nodes, Karnofksy index >70. Lymphoscintigraphy was performed 16–18 hours prior to surgery, following injection of 0.1–0.2 mL of 99mTc-Nanocoll: the administered activity was 3–4 MBq in group A (44 pts) and 7–8 MBq in group B (10 pts). The colloids were administered by transdermal supralesional injection in 49 patients with palpable nodules and by intraparenchymal ultrasound-guided injection in five patients with non-palpable nodules. Planar projections were performed starting from the 5th until the 80th min (or 180th in the event of late migration). In 10 patients further projections were acquired 14–18 h following tracer administration. All nodes identified by gamma probe (MR 100 Pol. Hi. Tech) were histologically evaluated by immunohistochemistry and standard histology. Scintigraphic visualization of the SN was obtained in 49 patients: in 38 of these patients there was only one SN while in 11 patients there were two or three SNs. The delayed scan made in 10 patients did not show any further nodes. In all patients given US-guided perilesional injections migration was late (after at least 60 min). Our study confirms the validity of the scintigraphic procedure, its safety for patients and health care workers, and the feasibility of interdisciplinary collaboration.

Radioguided Surgery of Breast Cancer: Radiation Protection Survey

The aim of this study was to estimate the radioactive risk for surgical staff performing radioguided sentinel lymph node (SN) biopsy and to calculate the contamination level in the operating room for assessment of the possible need for specific radiation protection procedures. We studied 20 patients who were selected for quadrantectomy and SN biopsy. The day before surgery a volume of 0.15 mL of 99mTc-nanocoll was injected: the activity was 3.11 ± 0.85 MBq in group A (15 pts) and 11.6 ± 0.6 MBq in group B (5 pts). External radiation to staff was evaluated by measuring the exposure rate in air one hour after radiopharmaceutical administration. The air KERMA rate during surgery was estimated considering the physical decay of 99mTc. Contamination of disposable materials and surgical instruments in the operating room was measured using a contamination monitor, whereas the residual activity in the SN and the injection site was measured with a gamma probe. The exposure rate at 20 cm from the injection site was 0.75 μSv/h when the most radioactive patients (group B) were treated. Contamination in the operating room proved to be negligible. Considering the number of radioguided treatments carried out by a surgeon in one year, an equivalent effective dose of 0.075 mSv was estimated; the recommended dose limit according to the relevant Italian law, DL 230/95, is 1 mSv/yr. Surgical staff therefore do not require a classification of “exposed workers'’ and there is no need to supply the operating room with special containers for radioactive waste.

CT Angiography ASPECTS Predicts Outcome Much Better Than Noncontrast CT in Patients with Stroke Treated Endovascularly

BACKGROUND AND PURPOSE

Noncontrast CT ASPECTS has been investigated as a predictor of outcome in patients with acute ischemic stroke. Our purpose was to investigate whether CTA source images are a better predictor of clinical and radiologic outcomes than NCCT ASPECTS in candidates for endovascular stroke therapy.

MATERIALS AND METHODS

CT scans of patients (n = 124) were independently evaluated by 2 readers for baseline NCCT and CTA source image ASPECTS and for follow-up ASPECTS. An mRS of ≤2 at 3 months was considered a favorable outcome. Receiver operating characteristic curve analysis was used to assess the ability of NCCT and CTA source image ASPECTS to identify patients with favorable outcomes. A stepwise multiple regression analysis was performed to find independent predictors of outcome.

RESULTS

Baseline CTA source image ASPECTS correlated better than NCCT ASPECTS with follow-up ASPECTS (r = 0.76 versus r = 0.51; P for comparison of the 2 coefficients < .001). Receiver operating characteristic curve analysis showed that baseline CTA source image ASPECTS compared with NCCT ASPECTS can better identify patients with favorable outcome (CTA source image area under the curve = 0.83; 95% CI, 0.76-0.91; NCCT area under the curve = 0.67; 95% CI, 0.58-0.77; P < .001). Finally, the stepwise regression analysis showed that lower age, good recanalization, lower time to recanalization, and good baseline CTA source image ASPECTS, not NCCT ASPECTS, were independent predictors of favorable outcome.

CONCLUSIONS

CTA source image ASPECTS predicts outcome better than NCCT ASPECTS; this finding suggests CTA rather than NCCT as a main step in the decision-making process for patients with acute ischemic stroke.

Ferritin-supported lipid bilayers for triggering the endothelial cell response

Hybrid nanoassemblies of ferritin and silica-supported lipid bilayers (ferritin-SLBs) have been prepared and tested for the adhesion, spreading and proliferation of retinal microvascular endothelial cells (ECs). Lipid membranes with varying surface charge were obtained by mixing cationic 1-palmitoyl-2-oleoyl-sn-glycero-3-ethylphosphocholine (POEPC) with zwitterionic 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) at increasing POPC/POEPC ratios. The supported bilayer formation and their subsequent interaction processes with ferritin were studied at the pH of 7.4 at different protein concentrations, by using the quartz crystal microbalance with dissipation monitoring and by atomic force microscopy. Both kinetics and viscoelastic parameters of the protein-lipid membrane interface were scrutinized, as well as surface coverage. Phase-contrast optical microscopy analyses of the ferritin-SLBs substrates after their interaction with endothelial cells evidenced the highest cell adhesion (2-4h of incubation time) and proliferation (from 24h to 5 days) for the membranes of POPC/POEPC (75:25 ratio). Moreover, ferritin increased both cell adhesion and proliferation in comparison to control glass (respectively 1.5- and 1.75-fold) as well as proliferation in comparison to bare POPC/POEPC (95:5 ratio) (2 fold). Results are very promising in the goal of modulating the endothelial cell response through the interplay of viscoelastic/charge properties of the solid-supported membranes and the SLB-conditioned ferritin activity.

Role of cytosolic and calcium independent phospholipases A(2) in insulin secretion impairment of INS-1E cells infected by S. aureus

Cytosolic PLA2 (cPLA2) and Ca(2+)-independent PLA2 (iPLA2) play a significant role in insulin β-cells secretion. Bacterial infections may be responsible of the onset of diabetes. The mechanism by which Staphylococcus aureus infection of INS-1 cells alters glucose-induced insulin secretion has been examined. After acute infection, insulin secretion and PLA2 activities significantly increased. Moreover, increased expressions of phospho-cPLA2, phospho-PKCα and phospho-ERK 1/2 were observed. Chronic infection causes a decrease in insulin release and a significant increase of iPLA2 and COX-2 protein expression. Moreover, insulin secretion in infected cells could be restored using specific siRNAs against iPLA2 isoform and specific COX-2 inhibitor.

Asthenozoospermia and membrane remodeling enzymes: a new role for phospholipase A2

Phosholipase A2 (PLA2 ) activity in the seminal plasma and in sperm heads is closely related to sperm motility and male fertility. Therefore, the purpose of this study was to investigate the possible involvement of different isoforms of phospholipase in asthenozoospermia. To accomplish this, cPLA2 , phospho-cPLA2 , iPLA2 , and sPLA2 were evaluated by immunofluorescence and immunoblot analyses in spermatozoa obtained from 22 normozoospermic men and 28 asthenozoospermic patients. We found significant differences in cPLA2 and its phosphorylated/activated form, iPLA2 , and sPLA2 content and distribution in normal and asthenozoospermic patients. cPLA2 was localized in heads, midpieces, and tails of all spermatozoa as constitutive enzyme, less expressed in the tail of spermatozoa with low progressive motility. While active phospho-cPLA2 distribution was homogeneous throughout the cell body of control-donor spermatozoa, lower levels were detected in the tails of asthenozoospermic patients, as opposed to its strong presence in heads. Low immunofluorescence signal for iPLA2 was found in astenozoospermic patients, whereas sPLA2 was significantly lower in the heads of asthenozoospermic patients. Spermatozoa with low progressive motility showed differences both in terms of total specific activity and of intracellular distribution. cPLA2 , iPLA2 , and sPLA2 specific activities correlated positively and in a significantly manner with sperm progressive motility both in normozoospermic men and asthenozoospermic patients. In conclusion, PLA2 s are expressed in different areas of human spermatozoa. Spermatozoa with low motility showed differences in total specific activity and enzyme distributions. We speculated that PLA2 expression and/or different distribution could be potential biomarkers of asthenozoospermia, one of the major causes of male factor infertility.

Effect of Sildenafil on Pre-Eclampsia-Like Mouse Model Induced By L-Name

N(omega)-nitro-L-arginine methyl ester (L-NAME) decreases the vasodilator effect of nitric oxide (NO) and induces pre-eclampsia in mouse. Sildenafil inhibits the degradation of nitric oxide and increases vasodilation. This study aimed to determine the effects of sildenafil citrate on angiogenesis and oxidative stress at the maternal foetal interface on pre-eclampsia-like mouse model induced by L-NAME. Twenty pregnant mice were divided into four groups: (i) vehicle control; (ii) L-NAME; (iii) sildenafil; (4) L-NAME+sildenafil. L-NAME was administered from day 7 of pregnancy and sildenafil from day 8 until day 16; animals were euthanized on day 17. Placental and foetal sizes and weights were measured; lipid peroxide levels and catalase activity in placental homogenates were determined, and placental vascular endothelia were identified by lectin-histochemistry using BSA-I lectin. Western blot analysis was used to determine VEGF expression in placental homogenates. No changes were seen in placental and foetal development in mice with normal pregnancies treated with sildenafil. Treatments with L-NAME reduced significantly the placental weight and average height and decreased the percentage of the endothelial surface. These alterations may be mediated by the reduction of NO levels in trophoblastic cells, due to the inhibitory effect of L-NAME on nitric oxide synthase (NOS) synthesis. This effect was offset by the treatment with sildenafil, with an increase in the percentage of the endothelial surface. In conclusion, our results indicate that treatment with sildenafil on pre-eclampsia mouse model can be used without adverse effects on the concept and its use in the treatment of pre-eclampsia is promising.

Subclinical central inflammation is risk for RIS and CIS conversion to MS

Background:

Subtle diffuse intrathecal inflammation is undetectable by conventional neuroimaging, and could influence multiple sclerosis (MS) disease course.

Objective:

To explore the role of subclinical persisting intrathecal inflammation in radiologically isolated syndrome (RIS) or clinically isolated syndrome (CIS) conversion to MS, and in early MS disease reactivation.

Methods:

One-hundred ninety-three subjects with RIS, CIS, relapsing–remitting (RR), or primary progressive (PP) MS were included, along with 76 matched controls. Cerebrospinal fluid (CSF) levels of interleukin-8 (IL-8), a major proinflammatory cytokine, were measured as a biomarker of intrathecal inflammation. Patients were followed up for 2 years. Clinical and imaging measures of disease progression were recorded.

Results:

High central contents of IL-8 were associated to clinical progression in subjects with RIS, and to the risk of conversion to MS in subjects with CIS. Asymptomatic intrathecal inflammation placed subjects at risk for MS conversion, even regardless lesion load. CSF IL-8 levels were higher in RR MS with high disease activity. Higher number of relapses in the first two years since diagnosis and shorter first inter-attack intervals were observed in patients with high levels of IL-8.

Conclusion:

IL-8 might provide utility in determining the presence of active intrathecal inflammation, and could be important in diagnostically undefined cases.

The autonomic balance predicts cardiac responses after the first dose of fingolimod

BACKGROUND

Predictive markers of cardiac side effects would be helpful for the stratification and individualized monitoring of multiple sclerosis (MS) patients prescribed with fingolimod.

OBJECTIVE

To test whether the autonomic balance predicts a cardiac response after the first dose of fingolimod.

METHODS

A total of 55 consecutive relapsing-remitting MS (RRMS) patients underwent 'head-up tilt', Valsalva maneuver, deep breathing and handgrip tests before their first dose of fingolimod. The normalized unit of the high frequency (HF) component (HF normalized units; HFnu), reflecting mostly vagal activity; and the low frequency (LF) component (LF normalized units; LFnu) reflecting mostly sympathetic activity, were considered for the analysis of heart rate (HR) variability. The patients' HR and electrocardiographic parameters ((the interval between P wave and ventricular depolarization (PR); the interval between Q and T waves (QT)) were recorded during 6-hour post-dose monitoring.

RESULTS

We found significant correlations between measures of parasympathetic function and fingolimod-induced bradycardia. Subjects with higher Valsalva ratio and HR variation during deep breathing had, in fact, nadir HR ≤ 50 beats/minute (bpm) after the first fingolimod dose. Conversely, significant negative correlations were found between measures of sympathetic function and fingolimod-induced PR interval increase. Subjects with lower LFnu at rest and less increase of blood pressure on the handgrip test showed a PR interval increase > 20 ms after fingolimod.

CONCLUSIONS

Assessing autonomic control of cardiovascular functions can be useful to predict cardiac effects after the first fingolimod dose.

Interleukin-8 is associated with acute and persistent dysfunction after optic neuritis

Background:

Acute optic neuritis is often in association with multiple sclerosis (MS). Proinflammatory cytokines trigger neuronal damage in neuroinflammatory disorders but their role in optic neuritis is poorly investigated.

Objective:

The objective of this work is to investigate the associations of intrathecal contents of proinflammatory cytokines with transient and persistent dysfunctions after optic neuritis.

Methods:

In 50 MS patients followed for up to six months, cerebrospinal fluid (CSF) levels of IL-1β, TNF and IL-8 were determined, along with clinical, neurophysiological and morphological measures of optic neuritis severity.

Results:

Visual impairment, measured by high- and low-contrast visual acuity, and delayed visual-evoked potential (VEP) latencies were significantly correlated to IL-8 levels during optic neuritis. IL-8 at the time of optic neuritis was also associated with persistent demyelination and final axonal loss, inferred by VEP and optical coherence tomography measures, respectively. Contents of IL-8 were correlated to functional visual outcomes, being higher among patients with incomplete recovery. Multivariate analysis confirmed that IL-8 significantly predicted final visual acuity, at equal values of demographics and baseline visual scores.

Conclusion:

Our study points to IL-8 as the main inflammatory cytokine associated with demyelination and secondary neurodegeneration in the optic nerve after optic neuritis.

Interleukin-1β alters the sensitivity of cannabinoid CB1 receptors controlling glutamate transmission in the striatum

Proinflammatory cytokines such as tumor necrosis factor-α and interleukin-1β (IL1β) regulate both excitatory and inhibitory synaptic transmission in the central nervous system. The interaction between IL1β and endocannabinoid system (ECS) is also emerging, based on the evidence that IL1β effects on striatal spontaneous excitatory and inhibitory postsynaptic currents are regulated by transient receptor potential vanilloid 1 (TRPV1) channels, members of the ECS. Furthermore, IL1β has also been shown to control the sensitivity of cannabinoid CB1 receptors controlling GABA transmission (CB1Rs(GABA)) in the striatum. To better detail the synaptic action of IL1β, and to clarify its complex interaction with the ECS, here we investigated the possible interplay between IL1β and CB1Rs controlling glutamate transmission (CB1Rs(glu)), other critical elements of the ECS. Our results show that the sensitivity of CB1Rs(glu) is fully blocked in the presence of IL1β in corticostriatal brain slices, and that the protein kinase C/TRPV1 pathway is involved in this effect. IL1β failed to modulate the sensitivity of glutamate synapses to the stimulation of GABAB receptors. We also provided evidence that IL1β-CB1Rs(GABA) but not IL1β-CB1Rs(glu) interaction is under the control of the brain-derived neurotrophic factor (BDNF)/trkB signaling and of lipid raft composition, because BDNF gene partial deletion, pharmacological blockade of trkB and membrane cholesterol removal with methyl-β-cyclodextrin all blocked IL1β-mediated inhibition of CB1Rs(GABA) but left unaltered the sensitivity of CB1Rs(glu) to this cytokine. Our results provide further evidence that synaptic transmission and the ECS are regulated by IL1β in the striatum.

Oral fingolimod rescues the functional deficits of synapses in experimental autoimmune encephalomyelitis

BACKGROUND AND PURPOSE Alterations of glutamate-mediated synaptic transmission occur early during neuroinflammatory insults, and lead to degenerative neuronal damage in multiple sclerosis (MS) and also in experimental autoimmune encephalomyelitis (EAE), which is a murine model of MS. Fingolimod is an effective orally active agent for the treatment of MS, affecting lymphocyte invasion of the brain. However, it is still unclear if fingolimod can be neuroprotective in this disorder. EXPERIMENTAL APPROACH Using neurophysiological recordings and morphological evaluation of dendritic integrity, we evaluated the effects of oral fingolimod on the clinical score of EAE mice in order to determine whether the compound was associated with preservation of synaptic transmission. KEY RESULTS Oral fingolimod prevented and reversed the pre- and postsynaptic alterations of glutamate transmission in EAE mice. These effects were associated with a clear amelioration of the clinical deterioration seen in EAE mice, and with a significant inhibition of neuronal dendritic pathology. Fingolimod did not alter the spontaneous excitatory postsynaptic currents in control animals, suggesting that only the pathological processes behind the inflammation-induced defects in glutamate transmission were modulated by this compound. CONCLUSIONS AND IMPLICATIONS The beneficial effects of fingolimod on the clinical, synaptic and dendritic abnormalities of murine EAE might correlate with the neuroprotective actions of this agent, as observed in MS patients. LINKED ARTICLE This article is commented on by Gillingwater, pp. 858-860 of this issue. To view this commentary visit http://dx.doi.org/10.1111/j.1476-5381.2011.01612.x.

Intramuscular fatty acid composition of lambs fed diets containing alternative protein sources

Thirty male Merinizzata italiana lambs were divided into three groups after weaning according to live weight. The diet of the three groups differed in the main protein source used in the concentrate, soybean meal for treatment SBM, faba bean for treatment FB and peas for treatment PEA. Lambs were fed ad libitum and slaughtered at about 160 days of age. Meat from the PEA group had higher proportions of the essential fatty acids C18:2 ω-6 and C18:3 ω-3 than from FB and SBM lambs and consequently its derivatives, C20:4 ω-6 and C20:5 ω-3 respectively, were higher in meat from PEA animals, compared to SBM and FB ones. The total n-3 fatty acids were highest in meat from PEA lambs and consequently PEA lambs showed a more favourable n-6/n-3 ratio. In conclusion the use of legume seeds such as peas in lamb diets positively affected intramuscular fatty acid composition.

The effects of dietary N-3 and antioxidant supplementation on erythrocyte membrane fatty acid composition and fluidity in exercising horses

REASONS FOR PERFORMING STUDY

Fatty acid supplementation could modulate erythrocyte membrane fluidity in horses at rest and during exercise, but information is lacking on the effect of exercise.

OBJECTIVES

To assess the effect of exercise with, and without, an oral antioxidant supplementation enriched with n-3 fatty acids on erythrocyte membrane fluidity (EMF) and fatty acid composition in eventing horses.

METHODS

Twelve healthy and regularly trained horses were divided randomly into 2 groups: group S received an oral antioxidant cocktail enriched in n-3 fatty acid (alphatocopherol, eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) whereas group P was placebo-treated. At the end of 4 weeks, all horses performed a standardised exercise test (ET) under field conditions. Venous blood was sampled before starting treatment (TO), immediately before (T1) as well as 15 min (T2) and 24 h (T3) after ET. Spin labelled (16-DOXYL-stearic acid) red blood cell membranes were characterised using the relaxation correlation time (Tc in inverse proportion to EMF). Fatty acid composition (%) of the membrane was determined by gas-liquid chromatography.

RESULTS

Supplementation did not induce changes in EMF (T1 vs. TO) but significant changes in membrane composition were observed and there were increases in n-3 polyunsaturated fatty acid PUFA, n-3/n-6 ratio, and total n-3 fatty acids. Exercise (T2 vs. T1) induced a significant decrease of EMF in group P (Tc: +19%, P<0.05) and nonsignificant decrease in group S (Tc: +5%), whereas membrane fatty acid composition did not change in either group. During the recovery period (T3 vs. T2), EMF decreased significantly in group S (Tc: +29%, P<0.05) and nonsignificantly in group P (Tc: +18%) without any significant changes in fatty acid composition.

CONCLUSION AND POTENTIAL RELEVANCE

An enriched oral antioxidant supplementation induced changes in membrane composition, which modulated the decrease in EMF induced by exercise. Long chain n-3 fatty acid supplementation might therefore be beneficial.

Protecting effect of vitamin E supplementation on submaximal exercise-induced oxidative stress in sedentary dogs as assessed by erythrocyte membrane fluidity and paraoxonase-1 activity

The aim of this placebo-controlled study was to investigate the effects of oral vitamin E supplementation for 10 weeks on exercise-induced oxidative damage in untrained dogs. Eight dogs were randomly assigned to a supplementation (n=4) or control (n=4) group and underwent two isolated submaximal exercise sessions, 10 weeks apart. Blood was collected during each session to measure erythrocyte membrane fluidity (EMF), paraoxonase-1 (PON1) activity, plasma malondialdehyde (MDA) and vitamin E concentrations. These biomarkers were measured in venous blood samples collected before (t(0)), just after (t, EMF only) and 1d (t+1d) and 7d (t+7d) after the dogs ran on a treadmill. Prior to vitamin E supplementation, exercise induced a significant decrease in PON1 activity, EMF, vitamin E concentration and a significant increase in MDA concentration at t+1d. After a 10 week vitamin E supplementation period, these exercise-induced changes in PON1 activity, EMF and MDA concentration were still significant in the control group, but not in the supplemented group. These results suggested that vitamin E supplementation had a protective effect on submaximal exercise-induced oxidative damage in sedentary dogs.

Effects of exercise and oral antioxidant supplementation enriched in (n−3) fatty acids on blood oxidant markers and erythrocyte membrane fluidity in horses

The aim of this study was to investigate in a placebo-controlled field study the effect of a (n-3)-vitamin supplementation on erythrocyte membrane fluidity (EMF), oxidant/antioxidant markers and plasmatic omega3/omega6 fatty acid ratio (FAR) in 12 eventing horses. Venous blood was sampled at rest before (PRE) and after (POST) a three week treatment period with either the supplement (group S, n=6) or a placebo (group P, n=6) as well as after 15min (POST E15') and 24h (POST E24h) after a standardised exercise test. The following markers were analysed: EMF, plasma antioxidant capacity of water and lipid soluble components, ascorbic acid, uric acid (UA), glutathione (reduced: GSH, oxidised: GSSG), vitamin E (Vit E), beta-carotene, glutathione peroxidase (GPx) and superoxide dismutase (SOD) activity, selenium, copper (Cu), zinc (Zn), oxidised proteins (Protox), lipid peroxides (Pool) and FAR. EMF did not differ between group S and P after treatment, but GPx remained unchanged in group S whereas it decreased in group P and plasma Cu/Zn ratio remained unchanged whereas it increased in group P. FAR were significantly increased in group S. Exercise induced a significant decrease of EMF (POST vs. E24h) in both groups, but which was significantly lower at E15' in group S than in group P. Exercise induced a significant increase of UA and ACW (POST vs. E15') and Protox (POST vs. E24h) in both groups. An exercise-related decrease in GSH and Pool (POST vs. E15') was found in group P, whereas Vit E and FAR (POST vs. E24h) significantly decreased in both groups. The study showed that exercise induced a decrease in EMF in horses associated with changes of blood oxidative balance. The (omega-3)-vitamin supplementation tested improved the oxidative balance poorly but delayed the exercise-induced decrease of EMF and increased the FAR.

Pored domes in adrenocortical capillaries. An ultrastructural study in mammals

The adrenocortical gland is one of the most vascularized organs of the mammalian body. It undergoes continuous morphological changes dynamically dependent upon special permeability conditions related to various physiological and physiopathological events. The adrenal cortex of different adult mammals (3 pigs, 2 mice, 3 sheep) was studied by means of scanning (SEM) and transmission (TEM) electron microscopy. As seen by SEM it is formed of polyhedral cells which delimit a characteristic continuous labyrinth system of intercellular lacunae occupied by sinusoid-like capillaries. The capillary wall is fenestrated and is lined by flattened endothelial cells with their nuclear part bulging into the capillary lumen. The fenestrae are round or oval pores measuring 50-100 nm in diameter. They are usually clustered to form sieve plates and characteristically present a thin membranous diaphragm. Irregular microelevations and dome-like projections are often seen. These structures are made of thin cytoplasmic plates interrupted by numerous small pores which show a sieve plate profile. The pored-domes on the nuclear portion seem to be identical in structure to those found in the thinner endothelial part; some of them appear to detach from the endothelial cell. The pored-domes are structurally comparable to those reported both in the renal glomerular endothelium and in liver sinusoids. These endothelial structures may be an expression of the high rate of filtration of these tissues and may be also related to the final step of the replacement of the sieve plates during endothelial regeneration.

[Chronic diarrhea and weight loss. Diverticulosis of the small intestine with bacterial overgrowth]

Chronische Durchfälle und Gewichtsverlust mit Hypalbuminämie und Vitamin B12-Mangel führten bei einer 77-jährigen Frau zur Diagnose einer Dünndarmdivertikulose. Die Symptomatik war Folge eines Malabsorptionssyndromes aufgrund einer bakteriellen Überwucherung. Eine siebentägige Therapie mit Ciprofloxacin brachte die Durchfälle zum Verschwinden und die Patientin begann wieder an Gewicht zuzunehmen.

Membrane fluidity and lipid content of human spermatozoa selected by swim-up method

In this work, we examined whether spermatozoa (spz) from normospermic fertile patients and selected by a swim-up (S-U) procedure had a particular membrane fluidity related to their maturity and their lipid content as compared with the sperm cells from the whole ejaculate (total sperm). Swim-up selected sperm had a reduced cytoplasmic space as revealed by a lower creatine kinase (CK) activity compared with total sperm (2 +/- 1 vs. 12 +/- 5 mUI/10(7) spz, p < 0.05). The cholesterol (Chol) and total phospholipid (PL) contents were significantly lower in S-U selected sperm than in total sperm (0.72 +/- 0.08 vs. 1.20 +/- 0.30 nmol/10(6) spz for Chol and 1.77 +/- 0.17 vs. 2.78 +/- 0.50 nmol/10(6) spz for PL, p < 0.05) and such a decrease was observed for the three major membrane PL: phosphatidylethanolamine (PE), phosphatidylcholine (PC) and sphingomyelin (SM). However, these decreases were not associated with a change in either Chol/PL or PC/(PC + PE) molar ratios. Membrane fluidity estimated by fluorescence polarization remained comparable between the S-U sperm fraction and total sperm (fluorescence polarization anisotropy, r, which is inversely proportional to the fluidity: 0.235 +/- 0.006 vs. 0.230 +/- 0.005). The sperm membrane fluidity obtained in normospermic patients was compared with abnormospermic ones (oligoasthenoteratospermia). In abnormospermic patients, the membrane fluidity was decreased in migrated spermatozoa compared with total sperm (anisotropy: 0.210 +/- 0.010 vs. 0.250 +/- 0.013, p < 0.01). Our data suggest that the S-U method selected a subpopulation of mature spermatozoa characterised by a low content of Chol and PL, likely related to a reduced membrane area. The fact that Chol/PL and PC/(PC + PE) molar ratios were unchanged shows a maintenance of the membrane quality. This was confirmed by the fluorescence anisotropy measurement showing no difference in plasma membrane fluidity between S-U selected sperm and total sperm. In abnormal semen the migrated spermatozoa had a lower fluidity compared with total sperm suggesting a defective sperm function. These results bring new elements characterizing the S-U selected spermatozoa.

Incubation of lipid emulsions with plasma lipoproteins modifies the fluidity of each particle

Lipid emulsions (LE) contain triglyceride (TG)-rich particles (TGRP) and phospholipid-rich particles (PLRP). Various lipid and protein exchanges take place during in vitro incubations of LE with lipoproteins. These composition changes affect physical properties of particles. The aim of this study was to determine the role of different LE particles and the effect of TG composition on physical modifications. Low density lipoproteins (LDL: 1.025 < d < 1.040 g/mL) or high density lipoproteins (HDL: 1.085 < d< 1.150 g/mL) were incubated with the following four LE or their TGRP or PLRP, which were manufactured with the same phospholipid emulsifier: long-chain triglycerides (LCT): 100% soybean oil; medium-chain triglycerides (MCT)/LCT (MCT/LCT, 5:5, w/w); FO (100% fish oil); and MLF541 (MCT/LCT/FO, 5:4:1, by wt). After incubation, modified LE particles and lipoproteins were analyzed by fluorescence polarization. Observed physical modifications were significant in emulsion particles (ordering effect) but not in lipoproteins and also were significant for TG composition effect. Since intact emulsion contained a large excess of TGRP over PLRP, it is not surprising that intact emulsion had the same behavior as TGRP alone, and that PLRP had the same physical characteristics as lipoproteins. TG loss and cholesterol and protein acquisitions by emulsion particles rigidify their envelope. The two emulsions containing FO were less ordered after incubation. In conclusion, incubation of LE with lipoproteins changes physical properties of each kind of particle, and TG composition of the emulsion affects emulsion particle changes but has no effect on LDL and HDL. These order modifications induce more effective exchanges between LE particles and lipoproteins and modify their metabolism; HDL changes may increase the reverse cholesterol transport.

Nicotine self-administration and withdrawal: modulation of anxiety in the social interaction test in rats

RATIONALE

Most smokers report smoking has an anxiolytic effect, which may contribute to nicotine dependence.

OBJECTIVE

To examine effects in the social interaction test (SI) of anxiety after 4 weeks' self-administered nicotine (15 infusions of 0.03 mg/kg, totalling 0.45 mg/kg per day), and after 24 and 72 h of withdrawal. The effect of exposure to the operant chamber on withdrawal responses was also examined.

METHODS

Animals were trained to self-administer saline or nicotine and after 4 weeks they were tested in SI after their daily self-administration session. Animals were retested after 24 and 72 h withdrawal, when they were either taken directly from the home cage or were tested 5 min after a 30-min exposure to the operant chamber.

RESULTS

Compared with the saline control group, the animals that had been self-administering nicotine for 4 weeks showed decreased social interaction with no decrease in locomotor activity, indicating a significant anxiogenic effect of the nicotine infusions. There was no change in social interaction after 24 and 72 h withdrawal from chronic nicotine, regardless of whether or not the rats were exposed to the operant chamber just prior to being tested.

CONCLUSIONS

Nicotine self-administration is not maintained because of its anxiolytic effect, but despite, or because of, its anxiogenic effect. There was no evidence of an anxiogenic response after either 24 or 72 h of withdrawal and thus increased anxiety on withdrawal from nicotine does not seem to contribute to nicotine self-administration.

Modulation of the phospholipid transfer protein-mediated transfer of phospholipids by diacylglycerols

Previous studies have shown that diacylglycerols (DAG) are formed during triglyceride hydrolysis in very low density lipoproteins (VLDL), a process that is accompanied by an elevated phospholipid transfer protein (PLTP)-mediated transfer of phospholipids (PL) from VLDL to high density lipoprotein. Because PLTP has been also shown to transfer DAG, we hypothesized that DAG might modulate PL transfer through a mechanism of competition with respect to PLTP. To address this question we performed in vitro PL transfer assays using specifically designed PL donor particles. These were single bilayer vesicles (SBV) and large (EM-L) or small (EM-S) lipid emulsions, containing various proportions of DAG. The PLTP-mediated transfers of PL decreased as the volumes of the particle cores increased (SBV > EM-S > EM-L). In all cases, these transfers were inhibited by DAG in a concentration-dependent manner. We determined the core-to-surface distribution of DAG and we measured their relative affinity for PLTP by comparison with that of PL. From these parameters, we calculated the theoretical effects of DAG on PL transfers that would result from a competition mechanism. The experimental data showed that the inhibiting effects of DAG on PL transfers were much more important than those predicted from our calculations. Additional data showed that a large part of DAG effects was in fact due to their ability to increase the viscosity of the particle PL surfaces, as calculated from electron spin resonance experiments. These results show that DAG can modulate the PLTP-dependent PL transfers, both by competition with PL and by increasing the viscosity of the particle surfaces. These findings might be physiopathologically relevant in situations where elevated plasma concentrations of DAG might result from hypertriglyceridemia.-Lalanne, F., C. Motta, Y. Pafumi, D. Lairon, and G. Ponsin. Modulation of the phospholipid transfer protein-mediated transfer of phospholipids by diacylglycerols. J. Lipid Res. 2001. 42: 142;-149.

Prostasomes inhibit the NADPH oxidase activity of human neutrophils

Prostasomes are particular lipid vesicles secreted by the prostate in human semen and involved in several physiological functions such as the improvement of sperm motility or immunomodulation. We have previously shown that they reduced the overall reactive oxygen species (ROS) production of seminal polymorphonuclear neutrophils (PMN). The present study was conducted to define the mechanism by which prostasomes inhibit the ROS production of blood and seminal PMN. The luminol chemiluminescence measuring total ROS production of blood PMN stimulated by either a phorbol ester (PMA) or a chemoattractant peptide, formyl-Met-Leu-Phe (fMLP) was significantly inhibited by prostasomes. The NADPH oxidase activity of the PMN was measured by 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1, 2-a]pyrazin-3-one (MCLA) chemiluminescence. Prostasomes inhibited the NADPH oxidase activity of blood or seminal PMN and increased the lag-phase of the enzyme after PMA stimulation. Prostasomes also inhibited significantly the NADPH oxidase activity of fMLP stimulated blood PMN, but the inhibition was not significant for seminal PMN. The lipid composition of blood PMN was analysed and compared to the lipid composition of prostasomes. This showed that prostasomes had a high cholesterol:phospholipid molar ratio and a high proportion of sphingomyelin. Together with the fact that prostasomes can rigidify the plasma membrane of blood PMN, these results led us to postulate that prostasomes inhibit the NADPH oxidase activity of PMN by lipid transfer from the prostasomes to the plasma membrane of the PMN.

Membrane fluidity predicts the outcome of cryopreservation of human spermatozoa

Semen cryopreservation is an important procedure in the treatment of human infertility. However, the ability of spermatozoa to survive freeze/thaw processes varies between patients. Cryopreservation-induced stress may result in membrane injury with consequent loss of sperm motility and viability. We investigated the relationship between the physico-chemical state of the human sperm membranes and their tolerance to cryopreservation. Conventional characteristics of 20 semen samples were analysed before and after cryopreservation as well as their membrane fluidity assessed by measuring the fluorescence polarization anisotropy, which is inversely proportional to the fluidity. Correlation between fluidity and post-thaw recoveries of motile and viable spermatozoa were examined. Results showed that membrane anisotropy markedly varies between patients. In cryopreserved spermatozoa, anisotropy values were significantly higher than in fresh spermatozoa. Furthermore, recovery of motile and viable spermatozoa after freeze/thaw was strongly correlated with anisotropy of fresh spermatozoa (P < 0.05). The higher the membrane fluidity was before freezing, the better was the response of spermatozoa to cryopreservation. The results indicate that the freeze/thaw process results in a rigidifying effect on the sperm membrane and suggest that sperm adaptability to freeze/thaw-induced stress could be dependent on their initial membrane fluidity. The latter finding has practical implications for predicting the response of spermatozoa following freezing and thawing and for improving the recovery of viable spermatozoa.

Abnormalities of erythrocyte membrane fluidity, lipid composition, and lipid peroxidation in systemic sclerosis: evidence of free radical-mediated injury

OBJECTIVE

To elucidate whether oxidative injury occurs in systemic sclerosis (SSc) and whether it affects the erythrocyte membrane (EM) properties.

METHODS

EM fluidity and lipid composition (cholesterol:phospholipid molar ratio [C:PL], fatty acid composition) were studied in 52 patients with SSc and in 53 subjects without SSc (32 with primary Raynaud's phenomenon [RP] and 21 healthy subjects [controls]). Fluidity was measured as the fluorescence anisotropy of the hydrophobic fluorescent probe DPH (1,6-diphenyl-1,3,5-hexatriene). Lipid peroxidation products were determined as thiobarbituric acid-reactive substances (TBARS).

RESULTS

EM fluidity was significantly lower in SSc patients than in primary RP patients and controls (P < 0.001). The EM C:PL molar ratio was significantly higher in SSc patients than in primary RP patients and controls (P < 0.05). Levels of EM polyunsaturated n6 fatty acids (PUFA n6) were significantly lower in SSc patients than in primary RP patients and controls (P < 0.001). TBARS were significantly increased in SSc patients compared with primary RP patients and controls (P < 0.001). Multiple regression analyses indicated that the reduced EM fluidity was partly due to its greater C:PL molar ratio, lower PUFA n6 content, and higher TBARS levels. EM fluidity was lower among patients with nailfold capillary loss (P < 0.001) and digital ischemic ulcers (P < 0.05). EM lipid peroxidation products were higher among patients with pulmonary involvement (bibasal pulmonary fibrosis [P < 0.05] and reduced levels of diffusing capacity for carbon monoxide [P < 0.001]) and among patients who were positive for anti-topoisomerase I antibodies (P < 0.05) or negative for anticentromere antibodies (P < 0.001).

CONCLUSION

Our findings support the idea that oxidative injury occurs in SSc and that, through lipid peroxidation, it induces structural and functional changes of the EM that may contribute to the development of the microvascular abnormalities that are seen in the disease.