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A cross-sectional study was carried out in Dumki Upazila of Patuakhali district in Bangladesh to assess the prevalence of stunting, wasting and underweight among the under-five children. Anthropometric measurements were taken from all children, aged 0-59 months in the studied area using wooden height board and digital weight machine. We used WHO Anthro software for analyzing the z scores of the children. A total of 4409 (2296 boys and 2113 girls) under five children were counted for anthropometric analysis. Regarding the Height-for-age Z-score (HAZ), the study revealed that the prevalence of stunting was 27.10% (95% CI: 25.8-28.5) of the children while 7.80% (95% CI: 7-8.6) were severe stunting. By assessing the Weight-for-height Z-score (WHZ), the study showed that 11.20% (95% CI: 10.3-12.1) were wasting whereas 3% (95% CI 2.5-3.5) were severe wasting. According to Weight-for-age Z-score (WAZ), about 18.20% (95% CI: 17-19.3) were underweight and 4.1% (95% CI: 3.5-4.7) were underweight. The findings of the study show that prevalence of stunting is very high. Focusing on childhood stunting is a high priority, and there should be comprehensive efforts to increase the overall nutritional status of the under-five children in this area.

International audience; Lipocyclopeptides isolated from marine sources hold great promise as new lead for therapeutics. Here, wepropose the first attempt towards the total synthesis of Trichormamide A. This synthesis will help to confirm the proposed structure of the cyclic lipopeptide.

Peptaibols are linear non ribosomal peptides which have been the object of intense research efforts regarding their synthesis and the elucidation of the mechanism allowing their insertion in biological membranes. Forty years after their discovery they are still considered as model compounds and suitable probes for the investigation of new approaches aiming to test the efficacy of new coupling reagents, to physically and spectroscopically investigate the way by which they interact with the lipid bilayer and to develop artificial membrane pores. The stable helical secondary structure adopted by the peptaibols turn to be an adequate platform for gaining insight on the structural modifications induced by the substitution of the amide bond by 1,2,3-triazoles, but also for monitoring the impact of newly designed α,α-dialkyl glycine with fluorinated and silylated side chains as 2-aminoisobutyric acid mimic. Peptaibols secondary structure dictated by Aib high content has inspired the development of foldamers. Challenges and investigations on the above mentioned topics are discussed in this brief review.

International audience; 1,4-Disubstituted-1,2,3-triazole (Tz) is widely used in peptides as a trans-amide bond mimic, despite having hazardous effects on the native peptide activity. The impact of amide bond substitution by Tz on peptide secondary structures is scarcely documented. We performed a Tz scan, by systematically replacing peptide bonds following the Aib residues with Tz on two model peptaibols: alamethicin F50/5 and bergofungin D, which adopt stable α- and 310 helices, respectively. We observed that the Tz insertion, whatever its position in the peptide sequences, abolished their antimicrobial activity. The structural consequences of this insertion were further investigated using CD, NMR and X-ray diffraction. Importantly, five crystal structures that were incorporated with Tz were solved, showing various degrees of alteration of the helical structures, from minor structural perturbation of the helix to partial disorder. Together, these results showed that Tz insertions impair helical secondary structures.

A highly efficient total synthesis of 3- epi -(+)-lycoricidine has been described for the first time from easily available ( S )-Garner aldehyde with an overall yield of 7% in 20 steps. Stereoselective nucleophilic addition, Sharpless asymmetric dihydroxylation, Dess–Martin periodinane oxidation, intramolecular aldol cyclization, and Luche reduction are the salient features of this approach.

We propose a simple and efficient strategy to significantly improve the antibacterial activity of peptaibols and other antimicrobial peptides by N-terminal capping with 1,2,3-triazole bearing various hydrophobic substituents on C-4. We showed, herein, that such N-terminal insertions on alamethicin F50/5 could enhance its antimicrobial activity on gram-positive bacteria without modification of its overall three-dimensional structure. Indeed, while the native peptide and its analogues shared comparable helical contents, the crystal structure of one of the most active derivative showed a local slight distortion of the N-terminal extremity, which was also observed in solution using NMR spectroscopy. Importantly, fluorescence studies showed that the N-capped derivatives had increased affinity for liposomes which may indicate they interacted more strongly with the bacterial membrane than alamethicin F50/5.

The present study investigated the alleviative effect of aqueous extract of Trichosanthes dioica fruit (AQTD) against arsenic induced cardiotoxicity in Wistar albino rats. AQTD (50 and 100 mg/kg) was administered orally to rats for 20 consecutive days before oral administration of sodium arsenite (10 mg/kg) for 8 days. Then the body weights, heart weights, hematological profile, serum biochemical profile; myocardial antioxidative parameters viz. lipid peroxidation, reduced and oxidized glutathione, glutathione-S-transferase, glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT), and DNA fragmentation were evaluated. Pretreatment with AQTD markedly and significantly normalized body weights, heart weights, hematological profile, serum biochemical profile and significantly modulated all the myocardial antioxidative parameters and reduced DNA fragmentation in arsenic intoxicated rats. Therefore, T. dioica fruit possessed remarkable alleviative effects against arsenic induced myocardial toxicity in Wistar albino rats mediated by amelioration of arsenic induced myocardial oxidative stress by several mechanisms.

A short and stereoselective route for the synthesis of 2-oxopiperazines is presented starting from different naturally abundant α-amino acids. The key synthetic steps involved amide coupling, Wittig reaction, HWE olefination, aza-Michael reaction, iodocyclization. This new pathway involving first report of iodocyclization to construct chiral substituted 2-oxopiperazines furnished final compounds in good yields.

An efficient enantioselective formal total synthesis of antimalarial natural product (-)-raphidecursinol B along with its all stereoisomers is described from commercially available 3,4,5-trimethoxybenzaldehyde using the Sharpless asymmetric dihydroxylation, regioselective α-tosylation, epoxide opening and Mitsunobu reaction as the key reaction steps.

A short and stereoselective route for the synthesis of 1-hydroxyquinolizidine, an advanced synthetic intermediate for the total synthesis of (+)-epiquinamide is presented. The key synthetic steps involve diastereoselective nucleophilic addition on l -serine derived Garner aldehyde and acid mediated (PTSA) ring closing metathesis. The methodology is also elaborated successfully for the total synthesis of (+)-α-conhydrine, an important piperidine alkaloid.

As a result of their easy availability in enantiomerically enriched form and their possession of synthetically transformable diverse functional groups, amino acids have been extensively used by synthetic organic and medicinal chemists as a chiral pool for access to heterocycles (monocycles, bicycles or polycycles, either bridged or fused). This review describes the syntheses of diverse asymmetric heterocycles with various membered rings (n = 3-9) followed by benzo or heteroannulated ones, for the period from 1996 to Dec. 2013. It details solution phase synthetic methodologies in which the naturally occurring α-amino acid is incorporated, totally or partially, into the final product.

As a result of their easy availability in enantiomerically enriched form and their possession of synthetically transformable diverse functional groups, amino acids have been extensively used by synthetic organic and medicinal chemists as a chiral pool for access to heterocycles (monocycles, bicycles or polycycles, either bridged or fused). This review describes the syntheses of diverse asymmetric heterocycles with various membered rings (n = 3-9) followed by benzo or heteroannulated ones, for the period from 1996 to Dec. 2013. It details solution phase synthetic methodologies in which the naturally occurring α-amino acid is incorporated, totally or partially, into the final product.

A highly efficient and convenient method for the synthesis of substituted chiral 1,4-oxazepanes and 1,4-diazepanes have been described from Garner aldehyde through reductive amination with amino ester hydrochlorides followed by intramolecular cyclization as the key steps.

We have synthesized a new series of aryl aryl methyl thio arenes (AAMTAs) and evaluated antimalarial activity in vitro and in vivo against drug-resistant malaria. These compounds interact with free heme, inhibit hemozoin formation, and prevent Plasmodium falciparum growth in vitro in a concentration-dependent manner. These compounds concentration dependently promote oxidative stress in Plasmodium falciparum as evident from the generation of intraparasitic oxidants, protein carbonyls, and lipid peroxidation products. Furthermore, AAMTAs deplete intraparasite GSH levels, which is essential for antioxidant defense and survival during intraerythrocytic stages. These compounds displayed potent antimalarial activity not only in vitro but also in vivo against multidrug-resistant Plasmodium yoelii dose dependently in a mouse model. The mixtures of enantiomers of AAMTAs containing 3-pyridyl rings were found to be more efficient in providing antimalarial activity. Efforts have been made to synthesize achiral AAMTAs 17-23 and among them, compound 18 showed significant antimalarial activity in vivo.

An efficient stereoselective synthesis of aminocyclopentitols from (S)- and (R)-Garner aldehydes is presented here. The key steps involved diastereoselective addition of vinylmagnesium bromide to a Garner aldehyde, ring closing metathesis, diastereoselective dihydroxylation and stereoselective reduction of the keto functionality.

The cellulolytic mesophilic isolate Streptomyces albolongus (A5) was used to determine the effect of nitrogen and carbon sources on the production of cellulolytic enzymes using cellobiose octaacetate (COA) as an inducer. The isolate was able to degrade various cellulosic carbon sources. However, the rate of degradation, production of extracellular protein, reducing sugar, saccharification and production of enzyme were enhanced when 0.6% COA was used as an inducer in addition to the main substrate. Among the nitrogen sources tested, beef extract showed maximum production of the enzyme (136.7 U/ml CMCase) in Winstead's medium. The enzyme production was further enhanced in the medium supplemented with 0.6% COA, which corresponded to 154.69 U/ml CMCase activity. Among the carbon sources, carboxymethylcellulose (CMC) was found to be the best carbon source and again supplementation of the medium with 0.6% COA enhances CMCase production. Other than CMCase activity, the organism also produced appreciable levels of filter paper cellulase (FPase), avicelase and â-glucosidase activities.Keywords: Streptomyces albolongus, Carboxymethylcellulose (CMC), Cellobiose octaacetate (COA), InductionDOI: http://dx.doi.org/10.3329/bjm.v24i1.1243 Bangladesh J Microbiol, Volume 24, Number 1, June 2007, pp 70-72