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1.
Article in English | MEDLINE | ID: mdl-37653626

ABSTRACT

BACKGROUND: Dominating David-derived networks are widely studied due to their fractal nature, with applications in topology, chemistry, and computer sciences. The use of molecular structure descriptors is a standard procedure that is used to correlate the biological activity of molecules with their chemical structures, which can be useful in the field of pharmacology. OBJECTIVE: This article's goal is to develop analytically closed computing formulas for eccentricity-based descriptors of the second type of dominating David-derived derived network. Thermodynamic characteristics, physicochemical properties, and chemical and biological activities of chemical graphs are just a few of the many properties that may be determined using these computation formulas. METHODS: Vertex sets were initially divided according to their degrees, eccentricities, and cardinalities of occurrence. The eccentricity-based indices are then computed using some combinatorics and these partitions. RESULTS: Total eccentricity, average eccentricity, and the Zagreb index are distance-based topological indices utilized in this study for the second type of dominating David-derived network, denoted as D_2 (m). CONCLUSION: These calculations will assist the readers in estimating the fractal and difficult-to-handle thermodynamic and physicochemical aspects of chemical structure. Apart from configuration and impact resistance, the D_2 (m) design has been used for fundamental reasons in a variety of technical and scientific advancements.

2.
Molecules ; 28(2)2023 Jan 05.
Article in English | MEDLINE | ID: mdl-36677612

ABSTRACT

A branch of graph theory that makes use of a molecular graph is called chemical graph theory. Chemical graph theory is used to depict a chemical molecule. A graph is connected if there is an edge between every pair of vertices. A topological index is a numerical value related to the chemical structure that claims to show a relationship between chemical structure and various physicochemical attributes, chemical reactivity, or, you could say, biological activity. In this article, we examined the topological properties of a planar octahedron network of m dimensions and computed the total eccentricity, average eccentricity, Zagreb eccentricity, geometric arithmetic eccentricity, and atom bond connectivity eccentricity indices, which are used to determine the distance between the vertices of a planar octahedron network.

3.
Molecules ; 27(19)2022 Sep 27.
Article in English | MEDLINE | ID: mdl-36234902

ABSTRACT

Chemical descriptors are numeric numbers that capture the whole graph structure and comprise a basic chemical structure. As a topological descriptor, it correlates with certain physical aspects in addition to its chemical representation of underlying chemical substances. In the modelling and design of any chemical network, the graph is important. A number of chemical indices have been developed in theoretical chemistry, including the Wiener index, the Randic index, and many others. In this paper, we look at the benzenoid networks and calculate the exact topological indices based on the degrees of the end vertices.

4.
Materials (Basel) ; 15(8)2022 Apr 14.
Article in English | MEDLINE | ID: mdl-35454580

ABSTRACT

Over the past few years, the popularity of graphene as a potential 2D material has increased since graphene-based materials have applications in a variety of fields, including medicine, engineering, energy, and the environment. A large number of graphene sheets as well as an understanding of graphene's structural hierarchy are critical to the development of graphene-based materials. For a variety of purposes, it is essential to understand the fundamental structural properties of graphene. Molecular descriptors were used in this study to investigate graphene sheets' structural behaviour. Based on our findings, reverse degree-based molecular descriptors can significantly affect the exchange-correlation energy prediction. For the exchange-correlation energy of graphene sheets, a linear regression analysis was conducted using the reverse general inverse sum indeg descriptor, RGISI(p,q). From RGISI(p,q), a set of reverse topological descriptors can be obtained all at once as a special case, resulting in a model with a high correlation coefficient (R between 0.896 and 0.998). Used together, these reverse descriptors are graphed in relation to their response to graphene. Based on this study's findings, it is possible to predict the exchange correlation energy as well as the geometric structures of graphene sheets with very little computational cost.

5.
Int J Quantum Chem ; 121(9): e26594, 2021 May 05.
Article in English | MEDLINE | ID: mdl-33612855

ABSTRACT

The spread of novel virus SARS-CoV-2, well known as COVID-19 has become a major health issue currently which has turned up to a pandemic worldwide. The treatment recommendations are variable. Lack of appropriate medication has worsened the disease. On the basis of prior research, scientists are testing drugs based on medical therapies for SARS and MERS. Many drugs which include lopinavir, ritonavir and thalidomide are listed in the new recommendations. A topological index is a type of molecular descriptor that simply defines numerical values associated with the molecular structure of a compound that is effectively used in modeling many physicochemical properties in numerous quantitative structure-property/activity relationship (QSPR/QSAR) studies. In this study, several degree-based and neighborhood degree sum-based topological indices for several antiviral drugs were investigated by using a M-polynomial and neighborhood M-polynomial methods. In addition, a QSPR was established between the various topological indices and various physicochemical properties of these antiviral drugs along with remdesivir, chloroquine, hydroxychloroquine and theaflavin was performed in order to assess the efficacy of the calculated topological indices. The obtained results reveal that topological indices under study have strong correlation with the physicochemical characteristics of the potential antiviral drugs. A biological activity (pIC50) of these compounds were also investigated by using multiple linear regressions (MLR) analysis.

6.
Saudi Pharm J ; 28(9): 1093-1100, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32922140

ABSTRACT

Quantitative structure-activity relationship (QSAR) represents quantitative correlation of chemical structural features called as molecular descriptors and pharmacological activity as response endpoints. Topological index is a molecular descriptor extensively used to study QSAR of pharmaceuticals to assess their molecular characteristics by numerical computation. Theoretical assessment of drug like molecules helps to expedite the drug design and discovery process by rationalizing the lead identification, lead optimization and understanding their mechanism of actions. Therefore, in this article, we have computed the general inverse sum indeg index, ISI α , ß of Hyaluronic acid-curcumin conjugates by using molecular structure analysis and edge partitioning technique. Many standard topological indices are obtained as a special case of ISI α , ß . We also proposed general inverse sum indeg polynomial ISI α , ß ( G n , x ) of Hyaluronic acid-curcumin conjugates from which many well-known polynomials are deduced.

7.
J Pak Med Assoc ; 64(12 Suppl 2): S70-5, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25989785

ABSTRACT

OBJECTIVE: To determine the frequency of early relapse after achieving good initial correction in children who were on clubfoot abduction brace. METHODS: The cross-sectional study was conducted at the Jinnah Postgraduate Medical Centre, Karachi, and included parents of children of either gender in the age range of 6 months to 3years with idiopathic clubfoot deformities who had undergone Ponseti treatment between September 2012 and June 2013, and who were on maintenance brace when the data was collected from December 2013 to March 2014. Parents of patients with follow-up duration in brace less than six months and those with syndromic clubfoot deformity were excluded. The interviews were taken through a purposive designed questionnaire. SPSS 16 was used for data analysis. RESULTS: The study included parents of 120 patients. Of them, 95(79.2%) behaved with good compliance on Denis Browne Splint, 10(8.3%) were fair and 15(12.5%)showed poor compliance. Major reason for poor and non-compliance was unaffordability of time and cost for regular follow-up. Besides, 20(16.67%) had inconsistent use due to delay inre-procurement of Foot Abduction Braceonce the child had outgrown the shoe. Only 4(3.33%) talked of cultural barriers and conflict of interest between the parents. Early relapse was observed in 23(19.16%) patients and 6(5%) of them responded to additional treatment and were put back on brace treatment; 13(10.83%) had minor relapse with forefoot varus, without functional disability, and the remaining 4(3.33%) had major relapse requiring extensive surgery. Overall success was recorded in 116(96.67%) cases. CONCLUSIONS: The positioning of shoes on abduction brace bar, comfort in shoes, affordability, initial and subsequent delay in procurement of new shoes once the child's feet overgrew the shoe, were the four containable factors on the part of Ponseti practitioner.

8.
J Enzyme Inhib Med Chem ; 26(4): 569-78, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21171899

ABSTRACT

A novel series of 6-(2-chloroquinolin-3-yl)-4-substituted-phenyl-6H-1,3-oxazin-2-amines were synthesized and evaluated for in vitro antimalarial efficacy against chloroquine sensitive (MRC-02) as well as chloroquine resistant (RKL9) strains of Plasmodium falciparum. The activity tested was at nanomolar concentration. ß-Hematin formation inhibition activity (BHIA(50)) of oxazines were determined and correlated with antimalarial activity. A reasonably good correlation (r = 0.49 and 0.51, respectively) was observed between antimalarial activity (IC(50)) and BHIA(50). This suggests that antimalarial mode of action of these compounds seems to be similar to that of chloroquine and involves the inhibition of hemozoin formation. Some of the compounds were showing better antimalarial activity than chloroquine against resistant strain of P. falciparum and were also found to be active in the in vivo experiment.


Subject(s)
Antimalarials/pharmacology , Chalcone/chemistry , Oxazines/pharmacology , Plasmodium falciparum/drug effects , Antimalarials/chemical synthesis , Antimalarials/chemistry , Cyclization , Epithelial Cells/drug effects , Epithelial Cells/microbiology , Hemeproteins/antagonists & inhibitors , Humans , Molecular Structure , Oxazines/chemical synthesis , Oxazines/chemistry , Parasitic Sensitivity Tests , Stereoisomerism , Structure-Activity Relationship
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