Hypertonic sodium lactate reverses brain oxygenation and metabolism dysfunction after traumatic brain injury

BACKGROUND

The mechanisms by which hypertonic sodium lactate (HSL) solution act in injured brain are unclear. We investigated the effects of HSL on brain metabolism, oxygenation, and perfusion in a rodent model of diffuse traumatic brain injury (TBI).

METHODS

Thirty minutes after trauma, anaesthetised adult rats were randomly assigned to receive a 3 h infusion of either a saline solution (TBI-saline group) or HSL (TBI-HSL group). The sham-saline and sham-HSL groups received no insult. Three series of experiments were conducted up to 4 h after TBI (or equivalent) to investigate: 1) brain oedema using diffusion-weighted magnetic resonance imaging and brain metabolism using localized ¹H-magnetic resonance spectroscopy (n = 10 rats per group). The respiratory control ratio was then determined using oxygraphic analysis of extracted mitochondria, 2) brain oxygenation and perfusion using quantitative blood-oxygenation-level-dependent magnetic resonance approach (n = 10 rats per group), and 3) mitochondrial ultrastructural changes (n = 1 rat per group).

RESULTS

Compared with the TBI-saline group, the TBI-HSL and the sham-operated groups had reduced brain oedema. Concomitantly, the TBI-HSL group had lower intracellular lactate/creatine ratio [0.049 (0.047-0.098) vs 0.097 (0.079-0.157); P < 0.05], higher mitochondrial respiratory control ratio, higher tissue oxygen saturation [77% (71-79) vs 66% (55-73); P < 0.05], and reduced mitochondrial cristae thickness in astrocytes [27.5 (22.5-38.4) nm vs 38.4 (31.0-47.5) nm; P < 0.01] compared with the TBI-saline group. Serum sodium and lactate concentrations and serum osmolality were higher in the TBI-HSL than in the TBI-saline group.

CONCLUSIONS

These findings indicate that the hypertonic sodium lactate solution can reverse brain oxygenation and metabolism dysfunction after traumatic brain injury through vasodilatory, mitochondrial, and anti-oedema effects.

Effect of acute and chronic excesses of dietary nitrogen on blood neutrophil functions in cattle

Excess dietary nitrogen (EDN) is commonly expected in dairy herds, but no data are available regarding its consequences on cattle immunity. In this study neutrophil functions were assessed during EDN in steers. In experiment 1, 4 one-month periods, 4 diets [16% crude protein (CP; DM basis), 20% CP based on soybean meal, 20% CP based on urea, and 24% CP based on urea and soybean meal], and 4 steers were included in a crossover design to determine the effects of a chronic excess. In experiment 2, the repercussions of an acute excess were assessed with 2 periods of 10 d, the same 4 steers, and 2 diets containing 14 and 20% CP. Sampling was done during the fourth week of each period in experiment 1, and on d 0, 1, 2, 3, 7, and 9 of each period in experiment 2. Individual blood biochemistry parameters were measured and neutrophil factors, such as counts, recovery after isolation, surface expression of CD11b and CD62L, phagocytosis, diapedesis, reactive oxygen species (ROS) production, and bacteria killing, were determined. Data were analyzed by general linear models of R, with period, diet or biochemical component, and animal as explanatory variables. The outcome variables were biochemical or immune variables. The variables diet, period, and animal were forced as fixed effects. Data collected over the entire period of experiment 2 were pooled. Several multiples linear regressions or ANOVA were performed and a Bonferroni correction was applied. In experiment 2 (acute EDN), neutrophil counts were negatively associated with nitrogen intake, conversely to CD62L expression. The observed relative neutropenia may be due to neutrophil margination because CD62L-expressing neutrophils are more likely to stick to endothelium. Interestingly, ROS production was changed by EDN: chronic EDN (experiment 1) was negatively associated with opsonized zymozan (OZ)-induced ROS production and acute EDN (experiment 2) with spontaneous ROS production. For chronic EDN, ROS production upon phorbol 12-myristate 13-acetate was not modified, in contrast to OZ stimulation. Decreased ROS production during chronic EDN probably involves the early events leading to ROS production, as OZ acts through membrane receptors and phorbol 12-myristate 13-acetate directly activates protein kinase C. This is the first study to provide evidence that the modifications of neutrophil functions produced by excess nitrogen depend on the intensity and duration of the excess. Further studies, including epidemiological studies during risk periods, are needed to resolve the issues linked to EDN.

Novel mutations in pyridoxine-dependent epilepsy

PURPOSE

Pyridoxine-Dependent Epilepsy (PDE) is a rare autosomal recessive disease with neonatal seizures resistant to conventional anti-epileptic drugs. This metabolic disease has to be diagnosed early and treated to improve outcome. We report on two new mutations that open new prenatal prospects and suggest a new diagnostic procedure.

CASE REPORT

We describe PDE in a neonate carrying two novel mutations in the ALDH7A1 gene: c.[852_856delCTTAG] + [1230C > A]; p.[(Phe410Leu)] + p.[(Leu285CysfsX26)]. This case also illustrates that diagnosis could have been made without any pyridoxine withdrawal, thanks to the measurement of biomarkers. The patient was successfully treated with pyridoxine supplementation and currently shows normal neurological development.

Targeted transgenesis at the HPRT locus: an efficient strategy to achieve tightly controlled in vivo conditional expression with the tet system

The tet-inducible system has been widely used to achieve conditional gene expression in genetically modified mice. To alleviate the frequent difficulties associated with recovery of relevant transgenic founders, we tested whether a controlled strategy of transgenesis would support reliable cell-specific, doxycycline (Dox)-controlled transgene expression in vivo. Taking advantage of the potent hypoxanthine-aminopterin-thymidine selection strategy and an embryonic stem (ES) cell line supporting efficient germ-line transmission, we used hypoxanthine phosphoribosyltransferase ( HPRT) targeting to insert a single copy tet-inducible construct designed to allow both glucocorticoid receptor (GR) and β-galactosidase (β-Gal) expression. Conditional, Dox-dependent GR and β-Gal expression was evidenced in targeted ES cells. Breeding ES-derived single copy transgenic mice with mice bearing appropriate tet transactivators resulted in β-Gal expression both qualitatively and quantitatively similar to that observed in mice with random integration of the same construct. Interestingly, GR expression in mice was dependent on transgene orientation in the HPRT locus while embryonic stem cell expression was not. Thus, a conditional construct inserted in single copy and in predetermined orientation at the HPRT locus demonstrated a Dox-dependent gene expression phenotype in adult mice suggesting that controlled insertion of tet-inducible constructs at the HPRT locus can provide an efficient alternative strategy to reproducibly generate animal models with tetracycline-induced transgene expression.

[Invasion of the pulmonary artery by an undifferentiated carcinoma]

INTRODUCTION

The diagnosis of chronic obstruction of the pulmonary artery is difficult. We present the case of a woman with an invasive, undifferentiated carcinoma of the pulmonary artery.

CASE REPORT

A 61 year old woman complained of increasing dyspnoea. This was evaluated by computed tomography which showed a defect in the main pulmonary artery. There was no clinical or radiological improvement following anticoagulant treatment for two months. A repeat CT scan showed a persisting intravascular defect and the diagnoses considered included post-embolic pulmonary arterial hypertension and angiosarcoma. A surgical biopsy was performed and pericardial and aortic tumour nodules were found during the operation. The pathological examination revealed undifferentiated carcinoma. Further investigations failed to reveal the primary site.

CONCLUSION

Invasion of the pulmonary artery by angiosarcoma or other tumour is part of the differential diagnosis of chronic thromboembolic disease. The diagnosis rests on histology obtained by an intravascular or surgical procedure. Complete surgical excision may be possible in angiosarcoma but it was impossible in our patient. The patient died despite two courses of chemotherapy and targeted therapy with erlotinib.

Efficacité du rituximab dans les hémophilies acquises: à propos de deux cas et revue de la littérature

INTRODUCTION

Acquired hemophilia due to an inhibitor of factor VIII is a rare clinical situation.

EXEGESIS

Rituximab is now used in the treatment of acquired hemophilia. We report two cases of acquired hemophilia treated by rituximab with efficiency.

CONCLUSION

Rituximab appears to be a first line immunosuppressive therapy in acquired hemophilia, especially in post-partum hemophilia.

Long-term efficacy and tolerability of flutamide combined with oral contraception in moderate to severe hirsutism: a 12-month, double-blind, parallel clinical trial

OBJECTIVE

Our objective was to test the efficacy and tolerability of three doses of flutamide (125, 250, and 375 mg) combined with a triphasic oral contraceptive (ethynylestradiol/levonorgestrel) during 12 months to treat moderate to severe hirsutism in patients with polycystic ovary syndrome or idiopathic hirsutism.

DESIGN

We conducted a randomized, double-blind, placebo-controlled, parallel clinical trial.

PATIENTS

A total of 131 premenopausal women, suffering from moderate to severe hirsutism, were randomized to placebo or 125, 250, or 375 mg flutamide daily associated with a triphasic oral contraceptive pill. Hirsutism (Ferriman-Gallwey), acne and seborrhea (Cremoncini), and hormone serum levels were monitored at baseline and at 3 (except hormone serum levels), 6, and 12 months. Side effects and biochemical, hematological, and hepatic parameters were assessed.

METHODS

We used three-way ANOVA (subject, dose, and visit) with Scheffé adjustment for multiple comparisons or nonparametrical Friedman test and least-squares mean (paired data) and Kruskall-Wallis test for unpaired data analyses. We used chi(2) or Fisher's test for categorical data.

RESULTS

A total of 119 patients were included in the intention-to-treat analysis. All flutamide doses induced a significant decrease in hirsutism, acne, and seborrhea scores after 12 months compared with placebo without differences among dose levels. Similar related side effects were observed with placebo and 125 mg flutamide (12.5%), and slightly higher with 250 mg (17.3%) and 375 mg (21.2%). No statistically significant differences were observed either among doses or compared with placebo.

CONCLUSIONS

Flutamide at 125 mg daily during 12 months was the minimum effective dose to diminish hirsutism in patients with polycystic ovary syndrome or with idiopathic hirsutism.

Axillary surgery in breast cancer patients

Surgeons have routinely removed ipsilateral axillary lymph nodes from women with breast cancer for over 100 years. The procedure provides important staging information, enhances regional control of the malignancy and may improve survival. As screening of breast cancer has increased, the mean size of newly diagnosed primary invasive breast cancers has steadily decreased and so has the number of women with lymph node metastases. Recognising that the therapeutic benefit of removing normal nodes may be low, alternatives to the routine level I/II axillary lymph node dissection have been sought. A decade ago sentinel lymph node biopsy (SLNB) was introduced. Because of its high accuracy and relatively low morbidity, this technique is now widely used to identify women with histologically involved nodes prior to the formal axillary node dissection. Specifically, SLNB has allowed surgeons to avoid a formal axillary lymph node biopsy in women with histologically uninvolved sentinel nodes, while identifying women with involved sentinel nodes who derive the most benefit from a completion axillary node dissection. Despite the increasing use of SLNB for initial management of the axilla in women with breast cancer, important questions remain regarding patient selection criteria and optimal surgical methods for performing the biopsy. This article discusses the evolution of axillary node surgery for women with breast cancer.

Influence de la déforestation sur le fonctionnement hydrologique de petits bassins versants tropicaux

Les régions tropicales subissent une déforestation importante. En Amérique du Sud,la forêt est généralement remplacée par une prairie, C'est pourquoi nous avons étudié le comportement hydrologique de 2 petits (1,5 ha) bassins versants. Un bassin (bassin B) est recouvert par une forêt primaire, tandis que le second (bassin A) a été défriché et transformé en prairie (Digitaria swazilandensis, programme ÉCÉREX, ORSTOM/CTFT). Ces bassins, situés en Guyane Française, sont proches (500 m), escarpés et principalement constitués par des sols à drainage vertical ralenti. Le climat est de type tmpical humide avec une température moyenne (26 °C) et des précipitations moyennes annuelles (3500 à 3900 mm/an) élevées. L'évapotranspiration réelle et potentielle de la forêt primaire sont respectivement égales à 1470 mm/an et 1565 mm/an, En période d'étiage, nous avons observé un écoulement permanent à l'exutoire du bassin A, alors que le bassin B en est dépourvu. Deux crues (24 mai 1992 et 15 mai 1993) ont été étudiées, simultanément sur les 2 bassins. Pendant les crues, nous avons prélevé des échantillons d'eau des précipitations (pluie et pluviolessivat), des ruisseaux et du sol. Sur ces sites, l'eau circulant dans les couches peu profondes du sol présente une concentration élevée en K+ et faible en Cl-. Une signature opposée caractérise l'eau des couches pmfondes du sol. L'analyse des relations existant entre les traceurs chimiques (K+, Cl-) et isotopique l80) ainsi l'étude des propriétés hydrodynamiques du sol permet de décomposer qualitativement l'hydrogramme de crue en 3 réservoirs: sol superficiel (écoulement hypodermique), sol intermédiaire (de 0 à - 0,4 m), sol profond (bassin B) ou nappe (bassin A). Une décomposition quantitative a été effectuée en utilisant des traceurs chimique (Cl-) et isotopique l80). Nous avons ainsi montré que les crues sur les 2 bassins sont dominées par l'écoulement issu des couches intermédiaires du sol qui représente environ la moitié de l'écoulement total de crue. Cependant,les mécanismes de génération des crues diffèrent sur les 2 bassins. Sur le bassin A, les couches profondes du sol sont saturées avant la crue et participent donc à la totalité de la crue. Au contraire, sur le bassin B, les couches profondes de sol atteignent la saturation peu de temps avant le pic de crue et participent donc essentiellement aux écoulement pendant la décrue. Ces résultats confirment les études hydrologiques réalisées précédemment (FRITSCH, 199Ù) et permettent d'identifier les mécanismes de genèse des crues et ainsi de mettre en évidence l'effet de la déforestation.

Oocyte quality in polycystic ovaries revisited: identification of a particular subgroup of women

PURPOSE

Our purpose was to assess the endocrine status of women with polycystic ovaries (PCO) undergoing IVF, and to compare oocyte quality with endocrine markers of the syndrome, in an attempt to define a subpopulation with poor quality oocytes.

METHODS

This was a retrospective study. Patients were first endocrinologically analyzed: serum levels of androgens (T, androstenedione, DHEAS), FSH, and LH as well as glucose and insulin after an oral glucose tolerance test (OGTT) were recorded and are expressed as absolute values and area under the curve (AUC). Subsequently, they were followed over a 2-year period in which patients underwent several attempts of IVF as well as serving as oocyte donors. Patients were divided into three groups: group I (n = 4) was women who displayed embryos unable to implant in 15 IVF cycles and 10 ovum donation cycles in which they served as donors; group II (n = 16) was PCO patients in whom IVF (n = 38) and/or oocyte donation cycles (n = 42) resulted in pregnancies; and group III (n = 13) was IVF patients with normal appearance of the ovaries by ultrasound. The endocrine status was compared with the IVF results.

RESULTS

There was no difference among groups in the endocrinological parameters tested, except for the OGTT which identified women in group I as having higher serum glucose and insulin levels than patients in groups II and III. Similarly, the OGTT showed higher serum glucose values in group II compared to group III. Women in group I were also obese. Patients in group III were older than PCO patients and needed more gonadotropins to reach an ovarian response which resulted in a reduced number of oocytes retrieved. Fertilization was also impaired in group I, in which no pregnancy was recorded.

CONCLUSIONS

This study shows that there is a particular subgroup of PCO patients with lower fertilization rates and embryos unable to implant. These patients are obese and nonhyperandrogenic and show derangements of insulin secretion.

[45,X/46, XYnf/47, XYnfYnf/46, X, dic (Ynf) (q12) mosaicism in a female patient with gonadal dysgenesis and the stigmata of Turner's syndrome]

A 17-year-old girl was referred to us because of primary amenorrhea and features of Turner's Syndrome. The karyotype obtained from peripheral lymphocytes cultures was mos 45,X/46, XYnf/47, XYnfYnf/46, X, dic (Ynf) (q12). The karyotype of fibroblasts derived from cultures of both gonads was mos 45, X/46, XYnf/47, XYnfYnf. The Y chromosome was non-fluorescent in all the examined lines. We report here the clinical and cytogenetic findings in a patient with an unusual sex chromosome mosaicism.

[Value of digital angiography in the preoperative evaluation of arteritis of the leg. Results of a national survey]

The results of a survey on the role of digital angiography in the preoperative assessment of chronic lower limb arteritis demonstrate the diagnostic utility of combining digital image processing and arteriophlebography in a radiological system. This technique allows a practically complete assessment at one go, which is also made possible by the use of small material and of low-osmolarity contrast media, thus reducing the need for extensive anesthesia other than local anesthesia.

Plasma levels of 3-methylhistidine after ingestion of the pure amino acid or of muscular proteins measured by radioimmunoassay

A radioimmunoassay for plasma 3-methylhistidine (3MeHis) measurements has been developed. The assay has no significant crossreactivity with 18 other amino acids including histidine, carnosine, anserine, and creatinine. In normal subjects who have eaten no meat for 36 hours, plasma levels are constant over a 24-hour period (8.78 +/- 0.48 mumol/L, mean +/- SD). The use of 3MeHis for the assessment of intestinal protein absorption and its potential use as a marker of protein degradation were evaluated by studying its plasma kinetics. The absorption of the free 3MeHis is rapid and reaches a peak after 75 minutes. The peak is delayed after meat ingestion and reaches a maximum after 180 minutes. The ratio of the 75- to 180-minute 3MeHis levels was 1.40 +/- 0.06 for pure 3MeHis and 0.78 +/- 0.06 after meat ingestion (P less than 0.001). Peak height and area under the plasma concentration versus time curve were proportional to the dose received, indicating first order kinetics for 3 MeHis. It has a half-life of 12.2 hours, a metabolic clearance rate of 0.08 L/h and volume of distribution is 11.7 +/- 1.7 L as calculated from the serum values which were obtained up to 24 hours after oral 3MeHis administration. Its endogenous production can therefore be calculated to be 116 mumols per day in young subjects. Thus, the radioimmunoassay develops the potential of this amino acid as a marker of protein degradation and absorption for physiological investigations.

[Specific binding of 3H-progesterone to a plasma protein in the guinea pig fetus]

The presence of a protein that binds specifically and with high affinity to progesterone is found in the plasma of fetal guinea Pig. Progesterone and 5 alpha-dihydroxyprogesterone strongly compete for the 3H-progesterone-protein complex. 5 beta-dihydroxy progesterone, 20 beta-dihydroxyprogesterone, testosterone and synthetic progestagen, R-5020 (17,21-dimethyl-19-norpregna-4, 9-diene-3,20 dione), also compete but less intensely. 17-hydroxyprogesterone, aldosterone, cortisol, oestradiol and oestrone have no effect. The 3H-progesterone-protein, complex has an affinity of Kd = 8.8 +/- 3.5 x 10(-10) M and in sucrose density gradient the sedimentation coefficient is 4.6 S.