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BACKGROUND: Undernutrition is one of the serious health problems among adolescents in India where 253 million adolescents are in the age group of 10-19 years. Since adolescents represent the next generation of adults, it is important to understand the nutritional status of adolescents. Even though several studies have been carried out in different states in India on adolescent undernutrition (stunting, wasting /underweight), there is no study or review that estimated the national pooled prevalence of adolescent undernutrition and its determinants. Therefore, this review aims to determine the pooled prevalence and determinants of undernutrition (stunting, underweight/wasting) among Indian adolescents. METHODS: A systematic review of eligible articles will be conducted using preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines. A comprehensive searching of the literature will be made in Pub Med, EMBASE, SCOPUS, Google, Google Scholar, and Cochrane databases. The quality of the articles included in the review will be evaluated using the Newcastle-Ottawa Scale (NOS) for observational studies in meta-analyses. The pooled prevalence and odds ratio of the associated risk factors or determinants with their 95% confidence interval will be computed using STATA version 16 software. The existence of heterogeneity among studies will be assessed by computing p-values of Higgins's I2 test statistics and Cochran's Q-statistics based on chi-square with a 5% level of significance among reported prevalence. Sensitivity analysis and subgroup analysis will be conducted based on study quality to investigate the possible sources of heterogeneity. Publication bias will be assessed through visual examination of funnel plots and objectively by Egger's regression test. This review protocol has been registered at PROSPERO (CRD42021286814). DISCUSSION: By collecting and summarizing information on adolescent undernutrition can be a step towards a better understanding of the prevalence of nutritional status of Indian adolescents and how the associated factors influence the prevalence of undernutrition. This review will provide directions for further research and healthcare practitioners. This summarized finding at the national level will provide impetus to build nutritional strategies and proper healthcare services to fight against undernutrition among the most ignored population.

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BACKGROUND: Prior estimation of toxicity of each and every, existing and yet to be synthesized chemicals is a must to elude their adverse effect on the environment. Experimental determination of such parameters is time consuming, cost effective and above all, it demands the sacrifice of many vertebrates. At this end, the REACH regulations advocate for the use of non-testing predictive methods such as read-across, weight-of-evidence and QSAR (quantitative structure-activity relationship) techniques. Among these methods, QSAR is found to be the best as it is based on molecular structure only. The descriptors used in deriving the model in QSAR vary according to the nature of the narcotics as well as the species used for. The success of a model in predicting the toxicity of a narcotic purely depends on the type of descriptors selected that explains the structural features closely related to the property under study. In this review, we have focused on the different types of descriptors and QSAR models used to explain the narcosis phenomenon. METHODS: Literature was scanned for acute toxicity of chemicals on species like tadpoles, protozoa, planktonic crustaceans, and small fishes like million fish, rainbow fish etc. from different sources. The toxicity and toxicants were classified considering their polarity and specific interactions of the compounds. Due to complex nature of the substrate, the mechanism of action of toxicant is uncertain. However, the overall results obtained from the biological study have been subjected to QSAR studies to obtain various models, which can provide some ideas on the mode of toxicological action. Different types of molecular descriptors derived both experimentally and theoretically have been used in the QSAR studies. RESULTS: Mostly biochemicals have a specific signature on oil/water partition (Ko/w, P), which is the crux in biological activity. Accordingly, the toxicological activities have good correlations with log P. Addition of some more structural descriptors improves the structure-toxicity relationship. Among these, electronic descriptors like EHOMO, ELUMO and ΔE derived from molecular orbitals have been used in the QSAR. ELUMO describing the energy of excited species of the molecule is found to be the most suitable one. Other molecular descriptors used in the QSAR include constitutional, topological and Abraham's solute descriptors. The models derived from the QSAR studies were found to be highly significant to predict the toxicology as well as to throw light on the mechanism. CONCLUSION: The best descriptor for aquatic narcosis is the KO/W or P. Addition of an electronic parameter (ELUMO) improves the QSAR to some extent. However, substitution of ELUMO by other class of molecular descriptors has also some statistical significance. To have a global QSAR model, in addition to P, some more appropriate descriptors are to be derived either experimentally or theoretically, latter being the more cost effective and easy in derivation.

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Two divergent series of novel chalcone analogs, one derived from 1-cyclohexylpyrrolidin-2-one and the other derived from 1-benzo[f]chromanone, were designed, synthesized and evaluated for cytotoxicity against two murine cancer cell lines. Two 1-benzo[f]chromanone analogs, 4g and 4j yielded moderate toxicity against both melanoma B16 and lymphoma L1210 cell lines with IC(50) values between the range of 5 and 6 µM. With an IC(50) value of 3.4 µM, compound 4g was also active against human MDA-MB-435 melanoma cells. X-ray structures of the ß-hydroxy ketone product (4a) and the α,ß-unsaturated ketone (4h) were collected, and confirm the syn-configuration between the carbonyl moiety and the ß-vinylic proton in 4h. X-ray structures of two 1-cyclohexylpyrrolidin-2-one derivatives were also obtained, and both showed an E-configuration for the double bond.

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The title compound, C(22)H(16)N(2)OS, is a chalcone analog with a thia-zolidinone core that was synthesized as a potential cytotoxic and anti-cancer agent. The structure is commensurately modulated by unit-cell doubling along the direction of the a axis of the cell. The two crystallographically independent mol-ecules are differerentiated by the dihedral angle between the mean planes of the benzyl-idene phenyl group against the thia-zolidin-4-one moiety, which is 5.01 (7)° in one mol-ecule, and 17.41 (6)° in the other. The two mol-ecules are otherwise close to being indistinguishable and are related by crystallographic pseudo-translation. The two mol-ecules are not planar but are slightly bent with the benzyl-idene and phenyl-imino substituents being bent upwards with respect to the center planes of the two mol-ecules. The degree of bending of the two halves of the thia-zolidin-4-one moieties (defined as the planes that inter-sect at the S atom) are 11.08 (7) and 15.88 (7)°. Packing of the mol-ecules is facilitated by C-H⋯π inter-actions and slipped π-π stacking between one of the phenyl rings and a neighboring ethylene π system [distance between the centroid of the ethylene group and the closest phenyl C atom = 3.267 (2) Å, Cg(phenyl)⋯Cg(ethylene) = 3.926 Å].

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Phase diagrams of pseudoternary systems of Tween-80, butanol, hexane and water were constructed by a visual titration method. The cloud points (CPs) at various compositions were determined and the variations in the cloud points were analyzed on the basis of changes in the composition of the different components in the microemulsions. A quantitative model was established by using multiple regression analysis considering weight percent of emulsifier (surfactant+cosurfactant) and oil as independent variables. A lowering in the CP with increase in emulsifier content and decrease in oil content was observed. Addition of sodium chloride also depressed the CP significantly. Further, with the increase in temperature the turbid phase started separating to three different transparent zones. The upper layer was recognized as the oil-rich phase, middle layer was due to microemulsion and the lower layer was found to be a micellar system. Metal ions and colored organic substrates partitioned into these different phases, which provides scope for applications in metal ion preconcentration.

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The sensitivity of the pyrene monomer emission spectrum to the polarity of a medium has been exploited to probe the adsorbed layer of a series of polyoxyethylated alkyl phenols on silica surface. Both the hydrophobicity and hydrophilicity of the surfactants are found to control the adsorption of the surfactants at the silica-water interface. In a series of surfactants having the same hydrophobic chain length but with different hydrophilic chain lengths, the presence of a smaller number of hydrophilic oxyethylene units leads to a conspicuous increase in adsorption density in the premicellar region compared to surfactants having a larger number of oxyethylene units. This has been attributed to the formation of small aggregates (hemimicelles) on the silica surface in the former. The formation of the aggregates gets support from the emission characteristics of pyrene. The number of surfactants constituting different aggregates has been determined.