Homology modelling, molecular dynamics simulation and docking evaluation of ß-tubulin of Schistosoma mansoni.

Schistosomiasis is one of the neglected diseases causing considerable morbidity and mortality throughout the world. Microtubules with its main component, tubulin play a vital role in helminthes including schistosomes. Benzimidazoles represent potential drug candidates by binding ß-tubulin. The study aimed to generate a homology model for the ß-tubulin of S. mansoni using the crystal structure of O visaries (Sheep) ß-tubulin (PDB ID: 3N2G D) as a template, then different ß-tubulin models were generated and two previously reported benzimidazole derivatives (NBTP-F and NBTP-OH) were docked to the generated models, the binding results indicated that both S. mansoni, S. haematobium were susceptible to the two NBTP derivatives. Additionally, three mutated versions of S. mansoni ß-tubulin wild-type were generated and the mutation (F185Y) seems to slightly enhance the ligand binding. Dynamics simulation experiments showed S. haematobium ß-tubulin is highly susceptible to the tested compounds; similar to S. mansoni, moreover, mutated models of S. mansoni ß-tubulin altered its NBTPs susceptibility. Moreover, additional seven new benzimidazole derivatives were synthesized and tested by molecular docking on the generated model binding site of S. mansoni ß-tubulin and were found to have good interaction inside the pocket.

Fetal growth restriction and intra-uterine growth restriction: guidelines for clinical practice from the French College of Gynaecologists and Obstetricians.

Small for gestational age (SGA) is defined by weight (in utero estimated fetal weight or birth weight) below the 10th percentile (professional consensus). Severe SGA is SGA below the third percentile (professional consensus). Fetal growth restriction (FGR) or intra-uterine growth restriction (IUGR) usually correspond with SGA associated with evidence indicating abnormal growth (with or without abnormal uterine and/or umbilical Doppler): arrest of growth or a shift in its rate measured longitudinally (at least two measurements, 3 weeks apart) (professional consensus). More rarely, they may correspond with inadequate growth, with weight near the 10th percentile without being SGA (LE2). Birthweight curves are not appropriate for the identification of SGA at early gestational ages because of the disorders associated with preterm delivery. In utero curves represent physiological growth more reliably (LE2). In diagnostic (or reference) ultrasound, the use of growth curves adjusted for maternal height and weight, parity and fetal sex is recommended (professional consensus). In screening, the use of adjusted curves must be assessed in pilot regions to determine the schedule for their subsequent introduction at national level. This choice is based on evidence of feasibility and the absence of any proven benefits for individualized curves for perinatal health in the general population (professional consensus). Children born with FGR or SGA have a higher risk of minor cognitive deficits, school problems and metabolic syndrome in adulthood. The role of preterm delivery in these complications is linked. The measurement of fundal height remains relevant to screening after 22 weeks of gestation (Grade C). The biometric ultrasound indicators recommended are: head circumference (HC), abdominal circumference (AC) and femur length (FL) (professional consensus). They allow calculation of estimated fetal weight (EFW), which, with AC, is the most relevant indicator for screening. Hadlock's EFW formula with three indicators (HC, AC and FL) should ideally be used (Grade B). The ultrasound report must specify the percentile of the EFW (Grade C). Verification of the date of conception is essential. It is based on the crown-rump length between 11 and 14 weeks of gestation (Grade A). The HC, AC and FL measurements must be related to the appropriate reference curves (professional consensus); those modelled from College Francais d'Echographie Fetale data are recommended because they are multicentere French curves (professional consensus). Whether or not a work-up should be performed and its content depend on the context (gestational age, severity of biometric abnormalities, other ultrasound data, parents' wishes, etc.) (professional consensus). Such a work-up only makes sense if it might modify pregnancy management and, in particular, if it has the potential to reduce perinatal and long-term morbidity and mortality (professional consensus). The use of umbilical artery Doppler velocimetry is associated with better newborn health status in populations at risk, especially in those with FGR (Grade A). This Doppler examination must be the first-line tool for surveillance of fetuses with SGA and FGR (professional consensus). A course of corticosteroids is recommended for women with an FGR fetus, and for whom delivery before 34 weeks of gestation is envisaged (Grade C). Magnesium sulphate should be prescribed for preterm deliveries before 32-33 weeks of gestation (Grade A). The same management should apply for preterm FGR deliveries (Grade C). In cases of FGR, fetal growth must be monitored at intervals of no less than 2 weeks, and ideally 3 weeks (professional consensus). Referral to a Level IIb or III maternity ward must be proposed in cases of EFW <1500g, potential birth before 32-34 weeks of gestation (absent or reversed umbilical end-diastolic flow, abnormal venous Doppler) or a fetal disease associated with any of these (professional consensus). Systematic caesarean deliveries for FGR are not recommended (Grade C). In cases of vaginal delivery, fetal heart rate must be monitored continuously during labour, and any delay before intervention must be faster than in low-risk situations (professional consensus). Regional anaesthesia is preferred in trials of vaginal delivery, as in planned caesareans. Morbidity and mortality are higher in SGA newborns than in normal-weight newborns of the same gestational age (LE3). The risk of neonatal mortality is two to four times higher in SGA newborns than in non-SGA preterm and full-term infants (LE2). Initial management of an SGA newborn includes combatting hypothermia by maintaining the heat chain (survival blanket), ventilation with a pressure-controlled insufflator, if necessary, and close monitoring of capillary blood glucose (professional consensus). Testing for antiphospholipids (anticardiolipin, circulating anticoagulant, anti-beta2-GP1) is recommended in women with previous severe FGR (below third percentile) that led to birth before 34 weeks of gestation (professional consensus). It is recommended that aspirin should be prescribed to women with a history of pre-eclampsia before 34 weeks of gestation, and/or FGR below the fifth percentile with a probable vascular origin (professional consensus). Aspirin must be taken in the evening or at least 8h after awakening (Grade B), before 16 weeks of gestation, at a dose of 100-160mg/day (Grade A).

Effect of a novel benzimidazole derivative in experimental Schistosoma mansoni infection.

Currently, praziquantel is the only drug of choice for treatment of schistosomiasis. Reports of praziquantel resistance raise concerns about future control of the disease. Therefore, the search for new schistosomicidal drugs is eminent. In this study, the effect of a novel benzimidazole-derived compound (compound BTP-Iso) was assessed in mice harboring adult Schistosoma mansoni (Egyptian strain). Mice were treated 42 days p.i. with compound BTP-Iso using two treatment regimens (200 or 300 mg/kg). In both regimens, there were significant reductions in the number of recovered S. mansoni worms especially females and in immature ova, in addition to a significant reduction in the number and size of hepatic granulomata. A dose of 300 mg/kg resulted in a significant decrease in intestinal and hepatic tissue egg loads. Effect on schistosomes was confirmed by scanning electron microscopy, where adult worms recovered from mice treated with 200 mg/kg of compound BTP-Iso revealed tegumental alternations, characterised by swelling of tegumental ridges, bleb formation, and mild erosion in male worms; however in females, there were extensive erosion and destruction of the tegumental surface. These promising results may encourage future use of compound BTP-Iso in the treatment of schistosomiasis. However, more research is needed to detect the effect of compound BTP-Iso on early developmental stages of S. mansoni and on other species of human schistosomes.

Efficient regioselective three-component domino synthesis of 3-(1,2,4-Triazol-5-yl)-1,3-thiazolidin-4-ones as potent antifungal and antituberculosis agents.

In research for promising antibacterial and antifungal compounds, a series of 2-aryl 3-[1,2,4]triazol-5-yl 4-thiazolidinones 1 were synthesized by a domino reaction of 5-amino-1H-[1,2,4]triazoles 3, aromatic aldehydes, and α-mercaptoacids in boiling toluene in the presence of molecular sieves 4 Å. Of the twenty novel 3-[1,2,4]triazol-5-yl 4-thiazolidinone derivatives, four compounds 2-benzo[d][1,3]dioxol-6-yl-3-[(3-morpholin-4-yl)-1H-1,2,4-triazol-5-yl)]-1,3-thiazolidin-4-one (1i), 2-(4-chlorophenyl)-5-methyl-3-[3-(4-methylpiperazin-1-yl)-1H-1,2,4-triazol-5-yl]-1,3-thiazolidin-4-one (1p), 2-benzo[d][1,3]dioxol-6-yl-3-[3-(4-methylpiperazin-1-yl)-1H-1,2,4-triazol-5-yl]-1,3-thiazolidin-4-one (1s), 2-benzo[d][1,3]dioxol-6-yl-5-methyl-3-[3-(4-methylpiperazin-1-yl)-1H-1,2,4-triazol-5-yl]-1,3-thiazolidin-4-one (1t) exhibited MICs of 4 µg/mL or less versus Mycobacterium tuberculosis. Moreover, these compounds were screened against Candida albicans. Compounds 1p, 1s gave MICs of 1 µg/mL or less, and were fungicidal. Finally, compound 1s was evaluated against an expanded fungal panel and showed good activity against Cryptococcus neoformans. In addition, compound 1s also appeared to be fungicidal against Aspergillus arrhizus, with MIC <1 µg/mL.

Dicationic phenyl-2,2'-bichalcophenes and analogues as antiprotozoal agents.

A series of phenyl-2,2'-bichalcophene diamidines 1a-h were synthesized from the corresponding dinitriles either via a direct reaction with LiN(TMS)2, followed by deprotection with ethanolic HCl or through the bis-O-acetoxyamidoxime followed by hydrogenation in acetic acid and EtOH over Pd-C. These diamidines show a wide range of DNA affinities as judged from their ΔT(m) values which are remarkably sensitive to replacement of a furan unit with a thiophene one. These differences are explained in terms of the effect of subtle changes in geometry of the diamidines on binding efficacy. Five of the eight compounds were highly active (below 6 nM IC50) in vitro against Trypanosoma brucei rhodesiense (T. b. r.) and four gave IC50values less than 7 nM against Plasmodium falciparum (P. f.). Only one of the compounds was as effective as reference compounds in the T. b. r. mouse model for the acute phase of African trypanosomiasis.

Efficient synthesis of (-)-gamma-lycorane alkaloid by two Bu3SnH-mediated radical cyclisations.

An asymmetric induction using (S)-1-arylethylamine-based chiral auxiliary and two Bu(3)SnH-mediated radical cyclisations have been developed for a total synthesis of (-)-gamma-lycorane (1). The first cyclisation proceeded in 5-endo-trig manner with moderate diastereoselectivtiy to give (3aR,7aR)-octahydroindol-2-one 6b as the major product using alpha-iodo-N-(6-oxocyclohexen-1-yl)-N-[(S)-1-phenylethyl] acetamide (5b). In the second cyclisation, the radical precursor 8 was used as substrate to construct the optically active lycorane skeleton 15 which was reduced using LiAlH4 into (-)-gamma-lycorane (1).

Perchlorate mixed-ligand copper(II) complexes of beta-diketone and ethylene diamine derivatives: thermal, spectroscopic and biochemical studies.

The present work carried out a study on perchlorate mixed-ligand copper(II) complexes which have been synthesized from ethylenediamine derivatives (3a-c) and beta-diketones. These complexes, namely [Cu(DA-Cl)(acac)H(2)O]ClO(4)4, [Cu(DA-Cl)(bzac)H(2)O]H(2)O.ClO(4)5, [Cu(DA-OMe)(acac)H(2)O]ClO(4)6, [Cu(DA-OMe)(bzac)H(2)O]ClO(4)7, [Cu(DA-H)(acac)H(2)O]2H(2)O.ClO(4)8 and [Cu(DA-H)(bzac)H(2)O]ClO(4)9 (where acac, acetylacetonate and bzac, benzoylacetonate) were characterized by elemental analysis, spectral (IR and UV-vis) and magnetic moment measurements. Thermal properties and decomposition kinetics of all complexes are investigated. The interpretation, mathematical analysis and evaluation of kinetic parameters (E, A, DeltaH, DeltaS and DeltaG) of all thermal decomposition stages have been evaluated using Coats-Redfern equation. The biochemical studies showed that, the diamines 3a-c have powerful effects on degradation of DNA and protein. The antibacterial screening demonstrated that, the diamine (DA-Cl), 3b has the maximum and broad activities against Gram +ve and Gram -ve bacterial strains.

2, 3-Bis(5-alkyl-2-thiono-1, 3, 5-thiadiazin-3-yl) propionic acid: one-pot domino synthesis and antimicrobial activity.

In a search for promising antibacterial and antifungal compounds, two new series of 2, 3-bis(5-alkyl-2-thiono-1, 3, 5-thiadiazin-3-yl)propionic acid 1 and their corresponding N, N-dimethylpropionamide 6 have been synthesized. The reaction of 2, 3-diaminopropionate 3, carbon disulfide, formaldehyde, and the appropriate alkyl amines furnished the title compound 1. N, N-dimethylpropionamides 6 were obtained by the reaction of 1 with dimethyl amine in the presence of POCl(3). The newly prepared compounds were screened in vitro against certain strains of Gram-positive and Gram-negative bacteria and compared with nalidixic acid and ciprofloxacin. Moreover, the title compounds were tested for their antifungal activity in vitro against Candida albicans, phytopathogenic, Penicillum expansum and Trichoderma hazianum, and aflatoxin-producing Aspergillus flavus. These compounds exhibit varied activity against the tested pathogenic bacteria and remarkable inhibitory effects on growth or sporulation of some of the tested fungal species.