The Wood equation allows consistent fitting of individual antibody-response profiles of Zika virus or SARS-CoV-2 infected patients.

Antibody kinetic curves obtained during a viral infection are often fitted using aggregated patient data, hiding the heterogeneity of individual humoral immune responses. Individual antibody responses can be modeled using the Wood equation and grouped according to their profile. Such modeling takes into account several important kinetic parameters, such as the day when antibody detection becomes positive [daypos], the day of the maximal response [daymax], the maximum antibody level [levelmax], and the day when antibody detection becomes negative [dayneg]. Potential associations between these profiles and studied factors can then be tested.

Peripherally inserted central catheters: a hidden emerging cause of infection outbreaks.

In our institution, between January 2010 and December 2017, 15 140 peripherally inserted central catheters (PICCs) were inserted in 12 314 patients. Using time-series analysis to evaluate the annual historical trend (AHT), we observed a significant increase in bloodstream infections (BSIs; AHT = 24; p < 0.001) and associated deaths (AHT = 3; p 0.02) in patient with PICCs. The risk of experiencing a BSI was significantly higher in patients with PICCs (odds ratio = 9.6; 95% confidence interval, 9.08-10.18; p < 0.001). To reduce PICC-related BSIs and their related mortality, it is important to limit the overuse of PICCs and to implement a 'no PICC' policy by limiting the insertion of PICCs to situations without other available options.

Description of 'Gorbachella massiliensis' gen. nov., sp. nov., 'Fenollaria timonensis' sp. nov., 'Intestinimonas timonensis' sp. nov. and 'Collinsella ihuae' sp. nov. isolated from healthy fresh stools with culturomics.

We report here the main characteristics of 'Gorbachella massiliensis' GD7T gen. nov., sp. nov., 'Fenollaria timonensis' GD5T sp. nov., 'Intestinimonas timonensis' GD4T sp. nov., and 'Collinsella ihuae' sp. nov. GD8T isolated from one fresh stool of a French volunteer. We used a bacterial culturomics approach combined with taxono-genomics.

'Bittarella massiliensis' gen. nov., sp. nov. isolated by culturomics from the gut of a healthy 28-year-old man.

We report here the main features of the proposed new bacterial genus Bittarella. The type strain 'Bittarella massiliensis' GD6T (CSUR P2149) was isolated from a stool sample from a healthy French man.

Drancourtella massiliensis gen. nov., sp. nov. isolated from fresh healthy human faecal sample from South France.

Strain GD1(T) gen. nov., sp. nov., is the type strain of the newly proposed genus and species Drancourtella massiliensis, belonging to the Clostridiales order. This strain, isolated from the stool of a healthy person, is a Gram-positive rod, oxygen intolerant and nonmotile, with spore-forming activity. The features of this organism and its genome sequence are described. The draft genome is 3 057 334 bp long with 45.24% G + C content; it contains 2861 protein-coding genes and 64 RNA genes.

Endogenous synthesis cannot compensate for absence of dietary oleic acid in rats.

It is important to know whether an organism is able to synthesize all the oleic acid it needs. To determine this, it is sufficient to feed animals a diet containing essential fatty acids but totally lacking oleic acid, and then determine whether tissue concentrations of fatty acids of the (n-9) series are altered due to insufficient endogenous synthesis of oleic acid from stearic acid. In fact, the effects of a total oleic acid deficiency have not previously been studied because all the vegetable oils used in human and animal nutrition contain this fatty acid in variable amounts. Thus, we fed rats semipurified diets whose lipids (triglycerides) were synthesized chemically. Female rats were fed the diets for 3 wk before mating, and their pups (fed the same diets) were killed when 21 and 60 d old. Generally speaking, oleic acid deficiency resulted in a lower level of this acid in the various organs examined (liver, kidney, testes, heart, muscle and sciatic nerve in 21-d-old rats and liver, kidney, heart, muscle and sciatic nerve in 60-d-old rats). Brain, myelin and nerve endings were not affected at either age. This lower level was accompanied by a higher level of 16:1(n-7) and, to a lesser extent, 18:1(n-7). Dietary supplementation with oleic acid (1666 mg/100 g diet) for up to 21 d resulted in normal levels of this fatty acid in some organs (liver, heart, sciatic nerve) but not in others (kidney, muscle, testes) and a decrease in 16:1(n-7), which returned to about the same levels as in the control group in all organs except liver. Adding small or large amounts of stearic acid to the oleic acid-deficient diet had little or no effect on oleic acid levels in the tissues. We conclude that rats (particularly in liver) do not have sufficient synthesizing potential to guarantee the normal fatty acid composition of certain organs if oleic acid is totally absent in the diet.

Dietary alpha-linolenic acid deficiency in adult rats for 7 months does not alter brain docosahexaenoic acid content, in contrast to liver, heart and testes.

In adult rats, 22:6(n - 3) dietary deficiency does not affect brain membranes, but has a significant effect on some other visceral organs. 60-day-old male rats fed a diet containing sufficient amounts of both linoleic and alpha-linolenic acid were divided into three groups. One group continued the same diet; the second was fed a diet containing 2% sunflower oil, the third was fed 10% sunflower oil (sunflower oil contains linoleic acid, but trace amount of alpha-linolenic acid). Animals were killed different times after receiving the new diets (1 to 31 weeks). For animals fed the diets containing only sunflower oil, deficiency in cervonic acid content (DHA, docosahexaenoic acid, 22:6(n - 3)) was not detected in whole brain, myelin or nerve endings within 31 weeks. In contrast, this acid progressively declined in liver, heart and testes up to 3 weeks and remained nearly stable thereafter. In parallel to the reduction of cervonic acid content, 22:5(n - 6) content increased in liver and heart, but not in testes. It also increased in brain, nerve endings and myelin from week 3, 6 and, 9 respectively. These results suggest that brain cervonic acid is highly preserved or is maintained at the expense of other organs.

Effect of dietary n-3 fatty acid deficiency on blood-to-brain transfer of sucrose, alpha-aminoisobutyric acid and phenylalanine in the rat.

Possible alterations in blood-to-brain unidirectional transport of sucrose (mol. wt., 342), alpha-aminoisobutyric acid (mol. wt., 104), and L-phenylalanine (mol. wt., 165) induced by a diet deficient in n-3 polyunsaturated fatty acids were studied with respect to blood-brain barrier function. Two groups of rats were for to two generations with a semisynthetic diet. One group of rats was fed a peanut oil+rapeseed oil diet which contained both essential fatty acids: linoleic acid (18:2 n-6) and alpha-linolenic acid, (18:3 n-3). Another group was fed a diet of peanut oil, this diet (containing 18:2 n-6) was deficient in alpha-linolenic acid. The experiments were performed at 6 months of age. Unidirectional transfer rate constants (Ki) of sucrose, alpha-aminoisobutyric acid and L-phenylalanine were measured. The diet based on peanut oil (deficient in n-3) caused a greater blood-to-brain transport of sucrose but not of alpha-aminoisobutyric acid or L-phenylalanine. These observations indicate that regardless of the mechanisms involved, alterations in essential fatty acids induced by diet can modulate to some extent the blood-brain transport of hydrophilic molecules without a carrier.