Ultrastructural Evidence for a Role of Astrocytes and Glycogen-Derived Lactate in Learning-Dependent Synaptic Stabilization.

Long-term memory formation (LTM) is a process accompanied by energy-demanding structural changes at synapses and increased spine density. Concomitant increases in both spine volume and postsynaptic density (PSD) surface area have been suggested but never quantified in vivo by clear-cut experimental evidence. Using novel object recognition in mice as a learning task followed by 3D electron microscopy analysis, we demonstrate that LTM induced all aforementioned synaptic changes, together with an increase in the size of astrocytic glycogen granules, which are a source of lactate for neurons. The selective inhibition of glycogen metabolism in astrocytes impaired learning, affecting all the related synaptic changes. Intrahippocampal administration of l-lactate rescued the behavioral phenotype, along with spine density within 24 hours. Spine dynamics in hippocampal organotypic slices undergoing theta burst-induced long-term potentiation was similarly affected by inhibition of glycogen metabolism and rescued by l-lactate. These results suggest that learning primes astrocytic energy stores and signaling to sustain synaptic plasticity via l-lactate.

Arteriovenous fistulae for access to hemodialysis in Chad : feasibility study of a medical civic action program by a French army surgical unit.

INTRODUCTION: Use of chronic intermittent hemodialysis is recent in Chad, where it remains underdeveloped. Vascular access is most commonly by catheter. The objective of our study was to demonstrate the feasibility of arteriovenous fistula (AVF) surgery for hemodialysis during deployments as part of the medical civic action program (MEDCAP). METHODS: We prospectively included all patients admitted for AVF creation at Camp Kossei forward surgical unit in N'Djamena (Chad) between December 2016 and February 2017. Surgery was performed by an experienced vascular surgeon. The data collected included age, sex, cause of kidney failure, type of anesthesia, AVF location, and the duration of the intervention and hospitalization. Patients were examined one month after the procedure to evaluate the functionality, morbidity, and mortality of the AVF. RESULTS: We performed 17 AVF in 3 months. Male to female ratio was 3. High blood pressure was the main cause of chronic kidney failure (55%). All interventions were conducted under locoregional anesthesia. Overall, 35% of fistulae were radiocephalic, 41% brachiocephalic, and 24% brachiobasilic. The mean duration of intervention was 58 minutes and that of hospitalization one day. No deaths occurred. Global morbidity, including non-functioning AVF, was 25%. CONCLUSION: Our study showed that AVF surgery is feasible during deployment, especially in Chad, and meets the needs of the local healthcare facilities. It should be developed and taught to local surgeons.

Inappropriate bradycardia in Ebola virus disease.

BACKGROUND: As part of French assistance for the outbreak of Ebola virus disease in west Africa, a military treatment center for infected healthcare workers was deployed in Conakry, Guinea. Although some cases of bradycardia have been reported since the first Ebola outbreak, they have never been documented to our knowledge. We studied heart rhythm in patients with Ebola virus disease to analyze inappropriate bradycardia and discuss its mechanism. METHODS: Nine patients who tested positive for Ebola were admitted in March 2015. Baseline clinical data were noted at admission and twice a day during follow-up, and laboratory analyses (with troponin testing) were performed. RESULTS: At admission, patients had no or moderate tachycardia (pulse = 82 ± 27 bpm). Among them, a 32-year-old midwife admitted on her fourth day of symptoms had marked bradycardia: 43 bpm. ECG showed sinus bradycardia with no conduction disturbances or repolarization anomalies; findings were similar for the three other patients with bradycardia (< 60 bpm). During follow-up, her pulse gradually increased, as it did for the other three; all four recovered. DISCUSSION: Despite several factors likely to promote tachycardia, we observed no or only moderate tachycardia in all patients with Ebola. In our study, ECG recorded sinus rhythm, without significant node dysfunction or atrioventricular block. In the absence of any evidence of myocarditis, we discuss the possibility of a central nervous system cause, associated with encephalitis. CONCLUSION: We observed relative or marked bradycardia in our patients infected with Ebola. We hypothesize that its causal mechanism was encephalitis.

[The intraosseous infusion in adult]. / La perfusion intraosseuse chez l'adulte.

Intraosseous infusion is an old knowledge, abandoned in the 1950s in favor of the peripheral vein, and it was essentially described in pediatrics and military medicine. Since 2005, this way is experiencing a resurgence of interest in emergency medicine particularly in adults after the failure's installation of a peripheral vein in order not to waste the time of care and administration of treatment. New devices that allow intraosseous infusion are currently used in humans. We propose to review the different kind of catheters used, to know the main technical characteristics, indications, contraindications and potential complications. We propose a comparison with the peripheral vein and a comparison between the different catheters.

Effects of abomasal infusion of flaxseed (Linum usitatissimum) oil on microbial ß-glucuronidase activity and concentration of the mammalian lignan enterolactone in ruminal fluid, plasma, urine and milk of dairy cows.

Ruminal microbiota plays an important role in the conversion of plant lignans into mammalian lignans. The main mammalian lignan present in the milk of dairy cows fed flax products is enterolactone (EL). The objectives of the present study were to investigate the effects of abomasal infusion of flax oil on the metabolism of flax lignans and concentrations of EL in biological fluids of dairy cows. A total of six rumen-cannulated dairy cows were assigned within a 2 × 3 factorial arrangement of six treatments utilising flax hulls (0 and 15·9 % of DM) and abomasal infusion of flax oil (0, 250 and 500 g/d). There were six periods of 21 d each. Samples were collected during the last 7 d of each period and subjected to chemical analysis. Flax hull supplementation increased concentrations of EL in ruminal fluid, plasma, urine and milk, while flax oil infusion had no effect. Post-feeding, ß-glucuronidase activity in the ruminal fluid of cows infused with 250 g flax oil was significantly lower for cows fed hulls than for those fed the control diet. The present study demonstrated that the presence of a rich source of n-3 fatty acids such as flax oil in the small intestine does not interfere with the absorption of the mammalian lignan EL and that lower ruminal ß-glucuronidase activity had no effect on the conversion of flax lignans into EL in the rumen of dairy cows.

Abomasal or ruminal administration of flax oil and hulls on milk production, digestibility, and milk fatty acid profile of dairy cows.

Four ruminally fistulated primiparous lactating Holstein cows were assigned to a 4 × 4 Latin square design to determine the effects of the site of administration (rumen or abomasum) of flax oil and flax hulls on diet digestibility and milk fatty acid profile of dairy cows. The treatments were 1) oil and hulls administered in the rumen and abomasal infusion of water (RUM/RUM), 2) oil and hulls infused in the abomasum (ABO/ABO), 3) oil administered in the rumen and hulls infused in the abomasum (RUM/ABO), and 4) oil infused in the abomasum and hulls placed in the rumen (ABO/RUM). Cows on the ABO/ABO and RUM/RUM treatments had the highest and lowest amounts of basal dry matter eaten, respectively. Higher dry matter digestibility was obtained when flax oil bypassed the rumen (ABO/ABO and ABO/RUM) compared with when flax oil was administered directly in the rumen (RUM/ABO and RUM/RUM). Apparent digestibility of ether extract was higher when flax hulls were administered in the rumen (RUM/RUM and ABO/RUM) compared with when flax hulls were infused in the abomasum (ABO/ABO and RUM/ABO). The lowest digestibility of acid detergent fiber and neutral detergent fiber was obtained when both flax products were added in the rumen, which may be attributed to the high amount of oil present in the rumen (7.8% of total dry matter input). The lowest yield of 4% fat-corrected milk was obtained for cows on the RUM/RUM treatment, probably as a result of lower dry matter intake and digestibility of fiber. Milk concentrations of protein, fat, total solids, and lactose were similar among treatments. Administration of oil and hulls in the rumen resulted in the highest concentrations of intermediate products of biohydrogenation and total trans fatty acids in milk fat compared with the other treatments. All ratios of n-6 to n-3 fatty acids in milk fat were lower than the 4 to 1 ratio recommended to improve human health. These results suggest that the presence of both flax oil and flax hulls in the rumen decreases 4% fat-corrected milk yield and digestibility but provides a desirable fatty acid profile of milk to enhance consumers' health.

Milk composition, milk fatty acid profile, digestion, and ruminal fermentation in dairy cows fed whole flaxseed and calcium salts of flaxseed oil.

Four ruminally lactating Holstein cows averaging 602+/-25 kg of body weight and 64+/-6 d in milk at the beginning of the experiment were randomly assigned to a 4 x 4 Latin square design to determine the effects of feeding whole flaxseed and calcium salts of flaxseed oil on dry matter intake, digestibility, ruminal fermentation, milk production and composition, and milk fatty acid profile. The treatments were a control with no flaxseed products (CON) or a diet (on a dry matter basis) of 4.2% whole flaxseed (FLA), 1.9% calcium salts of flaxseed oil (SAL), or 2.3% whole flaxseed and 0.8% calcium salts of flaxseed oil (MIX). The 4 isonitrogenous and isoenergetic diets were fed for ad libitum intake. Experimental periods consisted of 21 d of diet adaptation and 7 d of data collection and sampling. Dry matter intake, digestibility, milk production, and milk concentrations of protein, lactose, urea N, and total solids did not differ among treatments. Ruminal pH was reduced for cows fed the CON diet compared with those fed the SAL diet. Propionate proportion was higher in ruminal fluid of cows fed CON than in that of those fed SAL, and cows fed the SAL and CON diets had ruminal propionate concentrations similar to those of cows fed the FLA and MIX diets. Butyrate concentration was numerically higher for cows fed the SAL diet compared with those fed the FLA diet. Milk fat concentration was lower for cows fed SAL than for those fed CON, and there was no difference between cows fed CON and those fed FLA and MIX. Milk yields of protein, fat, lactose, and total solids were similar among treatments. Concentrations of cis-9 18:1 and of intermediates of ruminal biohydrogenation of fatty acids such as trans-9 18:1 were higher in milk fat of cows fed SAL and MIX than for those fed the CON diet. Concentration of rumenic acid (cis-9, trans-11 18:2) in milk fat was increased by 63% when feeding SAL compared with FLA. Concentration of alpha-linolenic acid was higher in milk fat of cows fed SAL and MIX than in milk of cows fed CON (75 and 61%, respectively), whereas there was no difference between FLA and CON. Flaxseed products (FLA, SAL, and MIX diets) decreased the n-6 to n-3 fatty acid ratio in milk fat. Results confirm that flax products supplying 0.7 to 1.4% supplemental fat in the diet can slightly improve the nutritive value of milk fat for better human health.

Administration of Pediococcus acidilactici or Saccharomyces cerevisiae boulardii modulates development of porcine mucosal immunity and reduces intestinal bacterial translocation after Escherichia coli challenge.

In this study, the influence of the probiotics, Pediococcus acidilactici (PA) and Saccharomyces cerevisiae boulardii (SCB), on intestinal immune traits and resistance to enterotoxigenic Escherichia coli (ETEC) infection was evaluated in pigs. Two weeks before farrowing, 30 sows and their future litters were allocated to the following treatments: 1) control group without antibiotic or probiotic treatment (CTRL), 2) control with antibiotic (tiamulin) added to weanling feed (ABT), or litters treated with 3) PA, 4) SCB, or 5) PA+SCB from 24 h after birth. During lactation, PA, SCB, or PA+SCB were given to piglets 3 times a week by gavage. After weaning at 21 d of age, probiotics or ABT were added to the diet. Four pigs per litter were chosen to evaluate performance and blood concentrations of folic acid and vitamin B(12). Three of these were orally challenged with an ETEC strain on d 49 to 51 and killed on d 52. Three piglets from the rest of the litter were slaughtered on d 18 and 3 others on d 24. Blood, ileum, and mesenteric lymph node (MLN) samples were taken to characterize leukocyte populations, determine IgA concentrations in ileal flushes, and evaluate bacterial translocation in MLN. No treatment effect on postweaning performance and on blood concentrations of folic acid and vitamin B(12) was observed. In the ileum, the percentage of CD4(-)CD8(+low) T cells was greater (P = 0.05) in 18-d-old nursed piglets treated with PA than in those of the CTRL and PA+SCB groups. In the MLN, the percentage of CD8(+) T cells was not affected by any of the treatments at d 18 and 24 but decreased (P = 0.006) after weaning. In the blood, CD8(+) T cells were not affected by treatments or weaning. After the ETEC challenge (d 52), bacterial translocation to MLN was reduced (P = 0.05) in pigs treated with PA, SCB, PA+SCB, or ABT compared with CTRL. No treatment effect was observed on blood leukocyte populations after ETEC challenge, although a time effect (d 42 vs. 52) indicated that blood CD4(+) and gammadelta-T lymphocytes were increased (P < 0.05) on d 52 compared with d 42, whereas CD4(-)CD8(+low) T lymphocytes and monocytes were markedly reduced (P < 0.01). Finally, the IgA concentration in ileal flushes collected on d 42 and 52 was greater in SCB and CTRL piglets than in ABT and PA piglets. In conclusion, probiotics may have the potential to modulate establishment of lymphocyte populations and IgA secretion in the gut and to reduce bacterial translocation to MLN after ETEC infection.

Concentration of the mammalian lignans enterolactone and enterodiol in milk of cows fed diets containing different concentrations of whole flaxseed.

A total of 32 lactating Holstein cows with mean body weight of 622 kg (s.e. = 24) were allotted, at week 25 of lactation, to eight groups of four cows blocked for similar days in milk. The objective of the experiment was to determine the effect of feeding four dietary concentrations (0, 50, 100 or 150 g/kg of dry matter) of whole flaxseed, which contains the plant lignan precursor secoisolariciresinol diglucoside (SDG), on concentrations of two mammalian lignans (enterodiol and enterolactone) in milk. The effects of the four diets on feed intake, milk production, milk composition and digestion were also studied. Cows within each block were assigned to one of the four isonitrogenous and isoenergetic total mixed diets and the experiment was carried out from week 25 to 29 of lactation. Diets were fed for ad libitum intake. Enterolactone was the mammalian lignan, of the two metabolites studied, detected in the milk of cows and its concentration in milk tended (P = 0.08) to increase linearly with higher intake of SDG in the diet. Feed intake, milk yield and milk composition were similar among diets. Milk fatty acid profile was slightly improved by feeding flaxseed, as shown by higher concentrations of fatty acids (e.g. n-3) recognized as being beneficial for human health. Those results suggest that feeding of whole flaxseed may result in changes in milk fatty acid composition and enterolactone content, which offer benefits for consumers.

Independent measurement of the total active 8B solar neutrino flux using an array of 3He proportional counters at the Sudbury Neutrino Observatory.

The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54_-0.31;+0.33(stat)-0.34+0.36(syst)x10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Deltam2=7.59_-0.21;+0.19x10(-5) eV2 and theta=34.4_-1.2;+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results.

In vitro metabolism of flax lignans by ruminal and faecal microbiota of dairy cows.

AIMS: To determine the in vitro conversion of plant lignans from two flax products (hull and seed) into the mammalian lignans, enterolactone and enterodiol, by bovine ruminal and faecal microbiota. METHODS AND RESULTS: Flax seeds and hulls were incubated in vitro over a 96-h time course with ruminal or faecal inoculum. Plant lignans in flax seeds and hulls averaged 9.2 and 32.0 nmol mg(-1), respectively. The highest net production of enterodiol at 72 and 96 h of incubation was obtained with flax hulls incubated with faecal microbiota. There was no difference in net production of enterodiol between flax products within the first 24 h of incubation. In general, net production of enterolactone over the 96-h time course was significantly higher for flax products incubated with ruminal than with faecal microbiota. Net production of enterolactone at 72 and 96 h of incubation was greater for flax hulls than flax seeds. CONCLUSIONS: Results of the present experiment suggest that, of the metabolites studied, the main mammalian lignan metabolite produced from flax hulls and seeds by ruminal microbiota is enterolactone while faecal microbiota leads mainly to the net production of enterodiol. SIGNIFICANCE AND IMPACT OF THE STUDY: This research will improve the understanding of the metabolic pathway of mammalian lignans in dairy cows, in order to enable targeted manipulation of their quantities in milk.

[Carotido-cavernous fistula after traumatic brain injury: an unusual vascular complication]. / Fistule carotidocaverneuse post-traumatique : une complication vasculaire inhabituelle.

The authors reported the case of a young man who suffered a cranial traumatism and showed neurological, ophthalmic and orbital signs with orbital bruit, cranial nerve palsy and chemosis while he was in the intensive care unit. Further examinations of imagery made it possible to highlight a high-flow carotid-cavernous fistula which was the origin of these symptoms and which was successfully treated by endovascular way. The aim of this article is to remind the reader of the characteristics of this pathology, in terms of epidemiology, physiopathology, clinical and paraclinical presentation, and therapeutic care.

Effect of postruminal glutamine supplementation on immune response and milk production in dairy cows.

Seventeen multiparous Holstein cows were used to examine the effect of an increased duodenal supply of Gln on immune function and production. Cows received continuous abomasal infusions of water (control: n = 8) or 300 g/d of Gln (n = 9) for 21 d starting within 48 h of calving. There were nonsignificant increases in milk and milk protein yields in response to Gln supplementation. Glutamine treatment had no effect on plasma glucose, nonesterified fatty acids (NEFA), or beta-hydroxybutyrate (BHBA) concentrations but did tend to increase plasma urea N concentration. The Gln treatment resulted in an increase of 108 microM in the plasma Gln concentration. Total essential AA concentrations decreased with the Gln treatment, whereas total nonessential AA concentrations were unaffected. T Lymphocyte proliferation did not differ between the control and Gln-treated cows. Treatment had no effect on the relative abundance of CD8 T cells but did increase the abundance of CD4 T cells. Cytokine production, as measured by IFN-gamma concentration determined in vitro in concanavalin-A-stimulated peripheral blood mononuclear cells, was similar between the treatments. Over the first 3 wk following calving, Gln supplementation had limited effects on milk production, metabolic parameters, and immune function.

Efficacy of botanical insecticides from Piper species (Piperaceae) extracts for control of Ruropean chafer (Coleoptera: Scarabaeidae).

Biopesticides, including botanicals, can offer a safe and effective alternative to conventional insecticides for controlling major insect pests within an integrated pest management program. The current study highlights the practical application of a botanical insecticide for controlling a major insect pest of turfgrass: European chafer, Rhizotrogus majalis (Razoumowsky). Greenhouse and field trials were conducted to test the efficacy of a botanical formulation based on black pepper, Piper nigrum L. (Piperaceae), seed extracts to R. majalis larvae. The 7-d P. nigrum extract LC50 for R. majalis third instars was 2.5%. Successful treatment in the field was accomplished with the application of a 2% P. nigrum formulation to turfgrass infested with R. majalis second and third instars, whereas 4% extract was required in a second field trial with older third instars. The 2% pepper extract activity was comparable with the conventional insecticide diazinon in the first field trial. However, the 4% pepper extracts significantly affected the earthworm populations in treated plots compared with diazinon in the second field trail. The analysis of soil residues for piperamides in the P. nigrum extract determined a half-life of 1 - 2.6 d in the first and second field trials, respectively. This confirmed the expectation that under field conditions the residual activity would be less than conventional insecticides, thereby reducing the environmental risk associated with pesticide use. We recommend the pepper formulation for spot treatment applications when population densities reveal an epicenter of infestation rather than broadcasting over large areas, thus helping to minimize cost and negative affects on nontarget invertebrates.

Influence of parturition and diets enriched in n-3 or n-6 polyunsaturated fatty acids on immune response of dairy cows during the transition period.

The objectives of this study were to evaluate the functional properties of immunocompetent cells in dairy cows fed diets enriched in n-3 or n-6 polyunsaturated fatty acids during the transition period. Six weeks before calving, 21 primiparous and 27 multiparous pregnant Holstein dairy cows were randomly allotted to 1 of 3 dietary fat treatments: calcium salts of palm oil (Megalac), micronized soybeans, or whole flaxseed, which are, respectively, rich in saturated, n-6, or n-3 fatty acids. On wk 6 and 3 before parturition, cows received a subcutaneous injection of ovalbumin to measure the antibody response in colostrum and serum. Colostrum samples were collected at the first milking after calving, and blood samples were taken 6, 3, and 1 wk before the expected calving date and 1, 3, and 6 wk after calving. Blood mononuclear cells were cultured to evaluate the proliferative response to concanavalin A and the in vitro productions of interferon-gamma, tumor necrosis factor-alpha, nitric oxide, and prostaglandin E2. The serum antibody response to ovalbumin was unaffected by dietary fatty acids, but the response was lower in primiparous cows than in multiparous cows. A significant diet x parity interaction indicated that colostral antibody level against ovalbumin was significantly higher in multiparous cows fed soybeans than in those fed flaxseed or Megalac; there was no difference among treatments for primiparous cows. The lymphocyte response to concanavalin A was lower in cows fed soybeans than in those receiving flaxseed or Megalac when the cells were incubated with autologous serum. The proliferative response of mononuclear cells incubated with autologous serum was suppressed in the 1st wk after calving in both primiparous and multiparous cows, and multiparous cows showed a higher response than primiparous cows throughout the experiment. There was a significant interaction between parity and diet as a result of a greater production of interferon-gamma by mononuclear cells incubated with autologous serum in multiparous cows than in primiparous cows fed flaxseed; there was no difference among cows fed the other diets. Interferon-gamma production was reduced around calving while the inverse was observed for productions of nitric oxide and tumor necrosis factor-alpha. Productions of nitric oxide, prostaglandin E2, and tumor necrosis factor-gamma were greater in primiparous cows than in multiparous cows. In conclusion, functional properties of lymphocytes and monocyte/macrophage lineage of dairy cows during the transition period are modulated by parturition and the composition of polyunsaturated fatty acids in the diet.

Measurement of the total active 8B solar neutrino flux at the Sudbury Neutrino Observatory with enhanced neutral current sensitivity.

The Sudbury Neutrino Observatory has precisely determined the total active (nu(x)) 8B solar neutrino flux without assumptions about the energy dependence of the nu(e) survival probability. The measurements were made with dissolved NaCl in heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21 +/- 0.27(stat)+/-0.38(syst) x 10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields Deltam(2)=7.1(+1.2)(-0.6) x 10(-5) eV(2) and theta=32.5(+2.4)(-2.3) degrees. Maximal mixing is rejected at the equivalent of 5.4 standard deviations.