Germination des Graines et Croissance en Pépinière et en Champ des Plantules de Detarium senegalense au Bénin

La plantation ou le semis est une méthode certaine pour asseoir rapidement sur le sol une couverture végétale de protection. L’utilisation réussie des semences ne peut être examinée sans une compréhension parfaite de leur physiologie. La présente étude sur Detarium senegalense a pour objectif de déterminer les paramètres de germination et la croissance des plants en pépinière et en champ. Les graines utilisées pour la germination ont subi plusieurs traitements. Le suivi de la croissance des plantules en pépinière et d’autres mis en champ a été effectué. Les données des paramètres de germination et de croissance ont été collectées et analysées. Les résultats ont montré que les graines de Detarium senegalense ont une forte potentialité de germination sans traitement avec un taux de germination de 76 % et un temps de latence de 20 jours. Les résultats du test de Kruskal-Wallis et d’analyse de la variance (ANOVA) ont montré que la durée de trempage des graines dans l’eau froide à température ambiante a un effet négatif sur le taux de germination des graines. En ce qui concerne le suivi de la croissance des plants, les résultats ont montré que les plants de Detarium senegalense ont un accroissement assez rapide. Les plants en pépinière ont atteint en moyenne une hauteur de 83,8 ± 2,28 cm après huit mois en pépinière. Tandis que les plants en champs quant à eux ont atteint une hauteur moyenne de 137,33± 7,08 cm. Les plants en champ ont une vigueur de croissance assez élevée que les plants en pépinière. Detarium senegalense a l’aptitude d’être utilisée dans les programmes de reboisement et de restauration des forêts dégradées après quatre mois en pépinière. Planting or sowing is a sure method for quickly placing a protective plant cover on the ground. The successful use of seeds cannot be examined without a perfect understanding of their physiology. The present study on Detarium senegalense aims to determine the parameters of germination and growth of plants in the nursery and in the field. Different treatments have been carried out on the seeds used for germination. The growth of seedlings in the nursery and other field crops was monitored. Data on germination and growth parameters were collected and analyzed. The results showed that the seeds of Detarium senegalense have a strong potential for germination without treatment with a germination rate of 76% and a standby time of 20 days. The results of the Kruskal-Wallis test and analysis of variance (ANOVA) showed that the duration of soaking the seeds in cold water at room temperature has a negative effect on the germination rate of the seeds. With regard to monitoring the growth of the plants, the results showed that the plants of Detarium senegalense have a fairly rapid growth. Nursery plants reached an average height of 83.8 ± 2.28 cm after eight months in the nursery. While the field plants have reached an average height of 137.33 ± 7.08 cm. Plants in the field have a fairly high growth vigor than plants in the nursery. Detarium senegalense hasthe ability to be used in reforestation and restoration programs for degraded forests after four months in the nursery

The High-Resolution Structures of the Neutral and the Low pH Crystals of Aminopeptidase from \u3cem\u3eAeromonas proteolytica\u3c/em\u3e

The aminopeptidase from Aeromonas proteolytica (AAP) contains two zinc ions in the active site and catalyzes the degradation of peptides. Herein we report the crystal structures of AAP at 0.95-Å resolution at neutral pH and at 1.24-Å resolution at low pH. The combination of these structures allowed the precise modeling of atomic positions, the identification of the metal bridging oxygen species, and insight into the physical properties of the metal ions. On the basis of these structures, a new putative catalytic mechanism is proposed for AAP that is likely relevant to all binuclear metalloproteases

Comparison of the internalization efficiency of LDL and transferrin receptors on L2C guinea pig lymphocytes

AbstractWe demonstrate that L2C lymphocytes have about 10-times more receptors for transferrin (TO than healthy lymphocytes, as has been shown in the case of LDL receptors. The dissociation constant is the same in the two cell types (about 4 × 10−7 M). In contrast to LDL, Tf enters L2C lymphocytes with very rapid kinetics. It is shown by cross-reaction that each receptor is internalized independently of the other

The \u3cem\u3edapE\u3c/em\u3e-encoded \u3cem\u3eN\u3c/em\u3e-Succinyl-l,l-Diaminopimelic Acid Desuccinylase from \u3cem\u3eHaemophilus influenzae\u3c/em\u3e Is a Dinuclear Metallohydrolase

The Zn K-edge extended X-ray absorption fine structure (EXAFS) spectra, of the dapE-encoded N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE) from Haemophilus influenzae have been recorded in the presence of one or two equivalents of Zn(II) (i.e. [Zn_(DapE)] and [ZnZn(DapE)]). The Fourier transforms of the Zn EXAFS are dominated by a peak at ca. 2.0 Å, which can be fit for both [Zn_(DapE)] and [ZnZn(DapE)], assuming ca. 5 (N,O) scatterers at 1.96 and 1.98 Å, respectively. A second-shell feature at ca. 3.34 Å appears in the [ZnZn(DapE)] EXAFS spectrum but is significantly diminished in [Zn_(DapE)]. These data show that DapE contains a dinuclear Zn(II) active site. Since no X-ray crystallographic data are available for any DapE enzyme, these data provide the first glimpse at the active site of DapE enzymes. In addition, the EXAFS data for DapE incubated with two competitive inhibitors, 2-carboxyethylphosphonic acid and 5-mercaptopentanoic acid, are also presented

Caractérisation Rhéologique Empirique Et Relative - Détermination De La Loi Constitutive Des Suspensions Eau Et Déchets Papiers-Cartons

Pour mettre au point un procédé de fabrication de briques autobloquantes à partir de déchets papier-carton, et d’en garantir la reproductibilité, maîtriser la qualité de la suspension eaux et déchets papier-cartons devient fondamental. En effet, cette suspension est mélangée avec du sable et du ciment pour obtenir les briques autobloquantes. Il est alors essentiel de déterminer la loi constitutive des suspensions eaux et déchets papier-carton. Une méthode de caractérisation rhéologique empirique et relative du type viscosimètre rotatif a été adoptée à partir de la conception et de réalisation d’un broyeur de déchets-papiers. Cette méthode propose d’utiliser ce broyeur comme rhéomètre de process et de définir la viscosité apparente de la suspension à partir de celle d’un fluide newtonien de référence qui nécessiterait la même puissance consommée dans des conditions opératoires et géométriques identiques. Dans le cadre de cette étude, la suspension eaux et déchets cellulosiques suit la loi d’Ostwald de Waële et l’eau est utilisée comme fluide de référence. La courbe caractéristique obtenue sur le broyeur avec l’eau sera comparée avec celles obtenues avec les différentes pâtes de papier. Les données mesurées sont les vitesses de rotation et les puissances électriques consommées pour en déduire les nombres de puissances (Np). À partir de la fonction modèle Np = k RexFry, les paramètres k, x, y seront déterminées pour ajuster les données expérimentales enregistrées. Pour constituer ces données expérimentales et modéliser les courbes caractéristiques du broyeur, l’inclinaison des pales de l’agitateur a été variée : 30° (T30), 45° (T45) et 60° (T60). Différents types de déchets cellulosiques ont également été utilisés : papiers journaux (PJ), papiers vélin (PV) et papiers cartons (PC). La vitesse de rotation du mobile passe de 1 tr/s, à 2,5 tr/s, à 4 tr/s, à 5 tr/s puis elle est augmentée par pas de 2,5 tr/s jusqu’à atteindre la vitesse maximale du moteur qui est de 25 tr/s. Les nombres de puissances obtenus des expériences ont été ajustés par la régression non-linéaire avec deux types de mises en équation sous MatLab. La première mise en équation a été faite par l’algorithme de Nelder Mead (N-M) qui, après 38 à 47 itérations et 75 à 88 évaluations des fonctions, a donné des valeurs de k, x et y. La deuxième a été faite par l’algorithme de Levenberg Marquadt (L-M) et a donné des valeurs de k, x, y après 4 à 5 itérations et 15 à 18 évaluations des fonctions. Ces deux méthodes donnent des résultats différents. Les nombres d’itérations montrent la puissance de chaque algorithme et celui de Levenberg Marquadt converge plus vite. Les valeurs du facteur de fiabilité R 1, qui signifie un comportement rhéoépaississant. Les suspensions eaux et déchets papiers-cartons sont généralement dans les mêmes classes des solutions d’amidons agitées.

Spectroscopic and X-ray Crystallographic Characterization of Bestatin Bound to the Aminopeptidase from \u3cem\u3eAeromonas (Vibrio) proteolytica\u3c/em\u3e

Binding of the competitive, slow-binding inhibitor bestatin ([(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoy]-leucine) to the aminopeptidase from Aeromonas proteolytica (AAP) was examined by both spectroscopic and crystallographic methods. Electronic absorption spectra of the catalytically competent [Co_(AAP)], [CoCo(AAP)], and [ZnCo(AAP)] enzymes recorded in the presence of bestatin revealed that both of the divalent metal ions in AAP are involved in binding bestatin. The electron paramagnetic resonance (EPR) spectrum of the [CoCo(AAP)]−bestatin complex exhibited no observable perpendicular- or parallel-mode signal. These data indicate that the two CoII ions in AAP are antiferromagnetically coupled yielding an S = 0 ground state and suggest that a single oxygen atom bridges between the two divalent metal ions. The EPR data obtained for [CoZn(AAP)] and [ZnCo(AAP)] confirm that bestatin interacts with both metal ions. The X-ray crystal structure of the [ZnZn(AAP)]−bestatin complex was solved to 2.0 Å resolution. Both side chains of bestatin occupy a well-defined hydrophobic pocket that is adjacent to the dinuclear ZnII active site. The amino acid residues ligated to the dizinc(II) cluster in AAP are identical to those in the native structure with only minor perturbations in bond length. The alkoxide oxygen of bestatin bridges between the two ZnII ions in the active site, displacing the bridging water molecule observed in the native [ZnZn(AAP)] structure. The M−M distances observed in the AAP−bestatin complex and native AAP are identical (3.5 Å) with alkoxide oxygen atom distances of 2.1 and 1.9 Å from Zn1 and Zn2, respectively. Interestingly, the backbone carbonyl oxygen atom of bestatin is coordinated to Znl at a distance of 2.3 Å. In addition, the NH2 group of bestatin, which mimics the N-terminal amine group of an incoming peptide, binds to Zn2 with a bond distance of 2.3 Å. A combination of the spectroscopic and X-ray crystallographic data presented herein with the previously reported mechanistic data for AAP has provided additional insight into the substrate-binding step of peptide hydrolysis as well as insight into important small molecule features for inhibitor design

Epidemiological, clinical and therapeutic profile of uterine fibroids at the Befelatanana University hospital centre of obstetric gynecology of Antananarivo, Madagascar

Background: Leiomyomas or fibromyomas more commonly referred as uterine fibroids are the most common tumors of the female genital tract. They affect 20 to 25% of women in genital activity. The objective of present study is to describe the epidemiological and therapeutic profile of uterine fibroids at the UHCOBG.Methods: Retrospective and descriptive cross-sectional study of patients with uterine fibroids hospitalized in the department of gynecology of the UHCOBG between January 2015 and December 2016.Results: In total, 101 cases of uterine fibroids have been identified with a prevalence of 3.92%. The average age is 42.75±3.6 years old. The most affected age group varies from 35 to 45 years old. Thirty-eight-point six percent of the patients were pauciparous. The medical history of irregular menstrual cycle disorders was present in 17.8% of the cases. The symptomatology was dominated by menometrorrhagia (78.2%) and in 67.3% of the cases, patients had anemia. The majority of patients (64.4%) had poly-myomatous uterus which fibroid location was predominantly corporeal (92.1%), isthmic (21.8%), and three quarters of the mapping was interstitial. Complications were dominated by aseptic necrobiosis (7.9%) and conservative treatment in 68.3% of the cases. Laparotomy is the pillar of a surgical treatment. The duration of hospitalization was short in 77.2% of the cases, 91.1% had a good progress and no death was noticed during 2 years.Conclusions: This is the first operative indication of all gynecological pathologies in present UHC and proves to be a real public health problem. The development of operative laparoscopy is necessary to reduce the morbidity associated with treatment

Investigating the circulating sphingolipidome response to a single high-intensity interval training session within healthy females and males in their twenties (SphingoHIIT): Protocol for a randomised controlled trial.

Introduction: Growing scientific evidence indicates that sphingolipids predict cardiometabolic risk, independently of and beyond traditional biomarkers such as low-density lipoprotein cholesterol. To date, it remains largely unknown if and how exercise, a simple, low-cost, and patient-empowering modality to optimise cardiometabolic health, influences sphingolipid levels. The SphingoHIIT study aims to assess the response of circulating sphingolipid species to a single session of high-intensity interval training (HIIT). Methods: This single-centre randomised controlled trial (RCT) will last 11 days per participant and aim to include 32 young and healthy individuals aged 20-29 (50% females). Participants will be randomly allocated to the HIIT (n= 16) or control groups (physical rest, n= 16). Participants will self-sample fasted dried blood spots for three consecutive days before the intervention (HIIT versus rest) to determine baseline sphingolipid levels. Dried blood spots will also be collected at five time points (2, 15, 30, 60min, and 24h) following the intervention (HIIT versus rest). To minimise the dietary influence, participants will receive a standardised diet for four days, starting 24 hours before the first dried blood sampling. For females, interventions will be timed to fall within the early follicular phase to minimise the menstrual cycle's influence on sphingolipid levels. Finally, physical activity will be monitored for the whole study duration using a wrist accelerometer. Ethics and dissemination: The Ethics Committee of Northwest and Central Switzerland approved this protocol (ID 2022-00513). Findings will be disseminated in scientific journals and meetings. Trial Registration The trial was registered on www.clinicaltrials.gov (NCT05390866, https://clinicaltrials.gov/ct2/show/NCT05390866) on May 25, 2022