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1.
BMC Med Genomics ; 17(1): 176, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956580

RESUMO

BACKGROUND: Intellectual disability (ID) is a neurodevelopmental condition affecting around 2% of children and young adults worldwide, characterized by deficits in intellectual functioning and adaptive behavior. Genetic factors contribute to the development of ID phenotypes, including mutations and structural changes in chromosomes. Pathogenic variants in the HCFC1 gene cause X-linked mental retardation syndrome, also known as Siderius type X-linked mental retardation. The MN1 gene is necessary for palate development, and mutations in this gene result in a genetic condition called CEBALID syndrome. METHODS: Exome sequencing was used to identify the disease-causing variants in two affected families, A and B, from various regions of Pakistan. Affected individuals in these two families presented ID, developmental delay, and behavioral abnormalities. The validation and co-segregation analysis of the filtered variant was carried out using Sanger sequencing. RESULTS: In an X-linked family A, a novel hemizygous missense variant (c.5705G > A; p.Ser1902Asn) in the HCFC1 gene (NM_005334.3) was identified, while in family B exome sequencing revealed a heterozygous nonsense variant (c.3680 G > A; p. Trp1227Ter) in exon-1 of the MN1 gene (NM_032581.4). Sanger sequencing confirmed the segregation of these variants with ID in each family. CONCLUSIONS: The investigation of two Pakistani families revealed pathogenic genetic variants in the HCFC1 and MN1 genes, which cause ID and expand the mutational spectrum of these genes.


Assuntos
Fator C1 de Célula Hospedeira , Deficiência Intelectual , Linhagem , Humanos , Paquistão , Masculino , Deficiência Intelectual/genética , Feminino , Fator C1 de Célula Hospedeira/genética , Proteínas Supressoras de Tumor/genética , Transativadores/genética , Criança , Sequenciamento do Exoma , Pré-Escolar
2.
Front Pharmacol ; 15: 1370833, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887556

RESUMO

Androgenic alopecia (AGA) affects both men and women worldwide. New blood vessel formation can restore blood supply and stimulate the hair regrowth cycle. Recently, our group reported that 2-deoxy-D-ribose (2dDR) is 80%-90% as effective as VEGF in the stimulation of neovascularization in in vitro models and in a chick bioassay. In this study, we aimed to assess the effect of 2dDR on hair growth. We prepared an alginate gel containing 2dDR, polypropylene glycol, and phenoxyethanol. AGA was developed in C57BL6 mice by intraperitoneally injecting testosterone (TE). A dihydrotestosterone (DHT)-treated group was used as a negative control, a minoxidil group was used as a positive control, and we included groups treated with 2dDR gel and a combination of 2dDR and minoxidil. Each treatment was applied for 20 days. Both groups treated with 2dDR gel and minoxidil stimulated the morphogenesis of hair follicles. H&E-stained skin sections of C57BL/6 mice demonstrated an increase in length, diameter, hair follicle density, anagen/telogen ratio, diameter of hair follicles, area of the hair bulb covered in melanin, and an increase in the number of blood vessels. Masson's trichrome staining showed an increase in the area of the hair bulb covered in melanin. The effects of the FDA-approved drug (minoxidil) on hair growth were similar to those of 2dDR (80%-90%). No significant benefit were observed by applying a combination of minoxidil with 2dDR. We conclude that 2dDR gel has potential for the treatment of androgenic alopecia and possibly other alopecia conditions where stimulation of hair regrowth is desirable, such as after chemotherapy. The mechanism of activity of 2dDR remains to be established.

3.
Int J Biol Macromol ; 271(Pt 2): 132443, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38761913

RESUMO

Metal-organic frameworks (MOFs)-based therapy opens a new area for antibiotic-drug free infections treatment. In the present study, chitosan membranes (CS) loaded with two concentrations of copper-MOF 10 mg/20 ml (Cu-MOF10/CS) & 20 mg/20 ml (Cu-MOF20/CS) were prepared by a simple lyophilization procedure. FTIR spectra of Cu-MOF10/CS and Cu-MOF20/CS dressings confirmed absence of any undesirable chemical changes after loading Cu-MOF. The SEM images of the synthesized materials (CS, Cu-MOF10/CS & Cu-MOF20/CS) showed interconnected porous structures. Cytocompatibility of the materials was confirmed by fibroblasts cells culturing and the materials were hemocompatible, with blood clotting index <5 %. Cu-MOF20/CS showed comparatively higher effective antibacterial activity against the tested strains; E. coli (149.2 %), P. aeruginosa (165 %) S. aureus (117.8 %) and MRSA (142 %) as compared to Amikacin, CS and Cu-MOF10/CS membranes. Similarly, Cu-MOF20/CS dressing significantly eradicated the biofilms; P. aeruginosa (37 %) and MRSA (52 %) respectively. In full thickness infected wound rat model, on day 23, Cu-MOF10/CS and Cu-MOF20/CS promoted wound healing up to 87.7 % and 82 % respectively. H&E staining of wounded tissues treated with Cu-MOF10/CS & Cu-MOF20/CS demonstrated enhanced neovascularization and re-epithelization along-with reduced inflammation, while trichrome staining exhibited increased collagen deposition. Overall, this study declares Cu-MOFs loaded chitosan dressings a multifunctional platform for the healing of infected wounds.


Assuntos
Antibacterianos , Bandagens , Biofilmes , Quitosana , Cobre , Liofilização , Estruturas Metalorgânicas , Pseudomonas aeruginosa , Cicatrização , Animais , Quitosana/química , Quitosana/farmacologia , Cicatrização/efeitos dos fármacos , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Ratos , Pseudomonas aeruginosa/efeitos dos fármacos , Porosidade , Cobre/química , Cobre/farmacologia , Biofilmes/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/terapia , Masculino , Indutores da Angiogênese/farmacologia , Indutores da Angiogênese/química , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia
4.
Int J Biol Macromol ; 258(Pt 2): 128966, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38147970

RESUMO

This study focused on the development and evaluation of a stable emulsion system using rice starch, protein isolates, and bran oil as food ingredients. This was performed using a one-factor-at-a-time (OFAT) experimental strategy, which was subsequently refined using response surface modeling (RSM), and the emulsion was then characterized. The resulting quadratic polynomial model effectively captured all the responses, with regression coefficients exceeding 0.90. The emulsion activity index, emulsion stability index, and droplet size were 86.29 %, 93.44 %, and 100.59 nm, respectively. Turbidity was significantly influenced by particle size, with the double emulsion (sample B) exhibiting higher turbidity index (43,250.34 ± 0.046) than the reference sample (29,433.303 ± 0.018). The viscosity of the emulsion increased with the addition of the protein isolates. This inferred that a stable emulsion system derived from rice could serve a multifunctional purpose as carriers, fillers, and binders to enhance the physical, functional and sensory properties of foods.


Assuntos
Oryza , Amido , Emulsões , Óleo de Farelo de Arroz
5.
Am J Transl Res ; 15(9): 5574-5593, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854221

RESUMO

BACKGROUND: Kidney renal clear cell carcinoma (KIRC) is the most prevalent type of renal cell carcinoma (RCC), with a high incidence and mortality rate. There is a lack of sensitive biomarkers. Therefore, the discovery of accurate biomarkers for KIRC patients is critical to improve prognosis. METHODS: We determined hub genes and their associated pathways involved in the pathogenesis of KIRC from the GSE66272 dataset consisting of KIRC (n = 26) and corresponding control (n = 26) samples and later validated the expression and methylation level of the identified hub genes on The Cancer Genomic Atlas (TCGA) datasets and Human RCC 786-O and normal HK-2 cell lines through RNA sequencing (RNA-seq), Reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and targeted bisulfite sequencing (bisulfite-seq) analyses. RESULTS: The identified up-regulated four hub genes include TYROBP (Transmembrane Immune Signaling Adaptor TYROBP), PTPRC (Protein tyrosine phosphatase, receptor type, C), LCP2 (Lymphocyte cytosolic protein 2), and ITGB2 (Integrin Subunit Beta 2). Moreover, the higher expression of TYROBP, PTPRC, LCP2, and ITGB2 in KIRC patients insignificantly correlates with a poor prognosis in KIRC patients. In addition, hub genes were involved in the "Fc epsilon RI signaling pathway, asthma, natural cell killer mediated cytotoxicity, T cell receptor signaling pathway, primary immunodeficiency, Fc gamma R-mediated phagocytosis, malaria, leukocyte transendothelial migration, and legionellosis" pathways and associated with the infiltration level of CD8+ T, CD4+ T, and macrophage cells. CONCLUSION: Our integrated in silico and in vitro analysis identified important hub genes (TYROBP, PTPRC, LCP2, and ITGB2) involved in the pathogenesis of KIRC as possible diagnostic biomarkers.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 299: 122814, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37201329

RESUMO

γ-Glutamytranspeptidase (GGT) is an important tumor biomarker that widely appears in the tumor cells. Therefore, accurate imaging and detection of GGT activity in live cells, serum and pathological cells grasp great importance for the diagnosis, management, and treatment of cancer. Herein, 2-(2-hydroxyl-phenyl)-6-chloro-4-(3H)-quinazolinone (HPQ) is considered as the fluorophore probe for the detection of GGT activity, which is known for the typical mechanism of excited-state intramolecular proton transfer (ESIPT). All the simulations adopted to evaluate the sensing mechanism were carried out via DFT and TDDFT calculations at CAM-B3LYP/TZVP level of theory. The emission properties of HPQ and HPQ-TD are thoroughly studied to understand the photoinduced electron transfer (PET) and excited state intramolecular proton transfer (ESIPT) process. The results reveal that the fluorescence quenching of HPQ (enol form) is assigned to the PET process, whereas the large Stokes shift in fluorescence emission of HPQ (keto form) is related with ESIPT mechanism. The obtained results are further cross validated by frontier molecular orbital (FMO) analysis, geometric analysis, and potential energy curve (PEC) scanning. Our calculations provide powerful evidence for the ESIPT based sensing mechanism of HPQ (keto-enol form) for GGT activity.


Assuntos
Corantes Fluorescentes , Prótons , Modelos Moleculares , Diagnóstico por Imagem , Teoria da Densidade Funcional
7.
Nanomaterials (Basel) ; 13(6)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36986015

RESUMO

Industrial pollutants pose a serious threat to ecosystems. Hence, there is a need to search for new efficient sensor materials for the detection of pollutants. In the current study, we explored the electrochemical sensing potential of a C6N6 sheet for H-containing industrial pollutants (HCN, H2S, NH3 and PH3) through DFT simulations. The adsorption of industrial pollutants over C6N6 occurs through physisorption, with adsorption energies ranging from -9.36 kcal/mol to -16.46 kcal/mol. The non-covalent interactions of analyte@C6N6 complexes are quantified by symmetry adapted perturbation theory (SAPT0), quantum theory of atoms in molecules (QTAIM) and non-covalent interaction (NCI) analyses. SAPT0 analyses show that electrostatic and dispersion forces play a dominant role in the stabilization of analytes over C6N6 sheets. Similarly, NCI and QTAIM analyses also verified the results of SAPT0 and interaction energy analyses. The electronic properties of analyte@C6N6 complexes are investigated by electron density difference (EDD), natural bond orbital analyses (NBO) and frontier molecular orbital analyses (FMO). Charge is transferred from the C6N6 sheet to HCN, H2S, NH3 and PH3. The highest exchange of charge is noted for H2S (-0.026 e-). The results of FMO analyses show that the interaction of all analytes results in changes in the EH-L gap of the C6N6 sheet. However, the highest decrease in the EH-L gap (2.58 eV) is observed for the NH3@C6N6 complex among all studied analyte@C6N6 complexes. The orbital density pattern shows that the HOMO density is completely concentrated on NH3, while the LUMO density is centred on the C6N6 surface. Such a type of electronic transition results in a significant change in the EH-L gap. Thus, it is concluded that C6N6 is highly selective towards NH3 compared to the other studied analytes.

8.
Nanomaterials (Basel) ; 13(2)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36678006

RESUMO

V-series nerve agents are very lethal to health and cause the inactivation of acetylcholinesterase which leads to neuromuscular paralysis and, finally, death. Therefore, rapid detection and elimination of V-series nerve agents are very important. Herein, we have carried out a theoretical investigation of carbon nitride quantum dots (C2N) as an electrochemical sensor for the detection of V-series nerve agents, including VX, VS, VE, VG, and VM. Adsorption of V-series nerve agents on C2N quantum dots is explored at M05-2X/6-31++G(d,p) level of theory. The level of theory chosen is quite adequate in systems describing non-bonding interactions. The adsorption behavior of nerve agents is characterized by interaction energy, non-covalent interaction (NCI), Bader's quantum theory of atoms in molecules (QTAIM), frontier molecular orbital (FMO), electron density difference (EDD), and charge transfer analysis. The computed adsorption energies of the studied complexes are in the range of -12.93 to -17.81 kcal/mol, which indicates the nerve agents are physiosorbed onto C2N surface through non-covalent interactions. The non-covalent interactions between V-series and C2N are confirmed through NCI and QTAIM analysis. EDD analysis is carried out to understand electron density shifting, which is further validated by natural bond orbital (NBO) analysis. FMO analysis is used to estimate the changes in energy gap of C2N on complexation through HOMO-LUMO energies. These findings suggest that C2N surface is highly selective toward VX, and it might be a promising candidate for the detection of V-series nerve agents.

9.
Materials (Basel) ; 15(21)2022 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-36363017

RESUMO

Continuous studies are being carried out to explore new methods and carrier surfaces for target drug delivery. Herein, we report the covalent triazine framework C6N6 as a drug delivery carrier for fluorouracil (FU) and nitrosourea (NU) anti-cancer drugs. FU and NU are physiosorbed on C6N6 with adsorption energies of -28.14 kcal/mol and -27.54 kcal/mol, respectively. The outcomes of the non-covalent index (NCI) and quantum theory of atoms in molecules (QTAIM) analyses reveal that the FU@C6N6 and NU@C6N6 complexes were stabilized through van der Waals interactions. Natural bond order (NBO) and electron density difference (EDD) analyses show an appreciable charge transfer from the drug and carrier. The FU@C6N6 complex had a higher charge transfer (-0.16 e-) compared to the NU@C6N6 complex (-0.02 e-). Frontier molecular orbital (FMO) analysis reveals that the adsorption of FU on C6N6 caused a more pronounced decrease in the HOMO-LUMO gap (EH-L) compared to that of NU. The results of the FMO analysis are consistent with the NBO and EDD analyses. The drug release mechanism was studied through dipole moments and pH effects. The highest decrease in adsorption energy was observed for the FU@C6N6 complex in an acidic medium, which indicates that FU can easily be off-loaded from the carrier (C6N6) to a target site because the cancerous cells have a low pH compared to a normal cell. Thus, it may be concluded that C6N6 possesses the therapeutic potential to act as a nanocarrier for FU to treat cancer. Furthermore, the current study will also provide motivation to the scientific community to explore new surfaces for drug delivery applications.

10.
Int J Mol Sci ; 23(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35628172

RESUMO

The investigation of natural bioactive injectable composites to induce angiogenesis during bone regeneration has been a part of recent minimally invasive regenerative medicine strategies. Our previous study involved the development of in situ-forming injectable composite hydrogels (Chitosan/Hydroxyapatite/Heparin) for bone regeneration. These hydrogels offered facile rheology, injectability, and gelation at 37 °C, as well as promising pro-angiogenic abilities. In the current study, these hydrogels were modified using glycerol as an additive and a pre-sterile production strategy to enhance their mechanical strength. These modifications allowed a further pH increment during neutralisation with maintained solution homogeneity. The synergetic effect of the pH increment and further hydrogen bonding due to the added glycerol improved the strength of the hydrogels substantially. SEM analyses showed highly cross-linked hydrogels (from high-pH solutions) with a hierarchical interlocking pore morphology. Hydrogel solutions showed more elastic flow properties and incipient gelation times decreased to just 2 to 3 min at 37 °C. Toluidine blue assay and SEM analyses showed that heparin formed a coating at the top layer of the hydrogels which contributed anionic bioactive surface features. The chick chorioallantoic membrane (CAM) assay confirmed significant enhancement of angiogenesis with chitosan-matrixed hydrogels comprising hydroxyapatite and small quantities of heparin (33 µg/mL) compared to basic chitosan hydrogels.


Assuntos
Quitosana , Hidrogéis , Quitosana/química , Durapatita/química , Glicerol , Heparina/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Engenharia Tecidual
11.
RSC Adv ; 12(7): 3909-3923, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35425404

RESUMO

In the current study, a covalent triazine framework (CTF-0) was evaluated as an electrochemical sensor against industrial pollutants i.e., O3, NO, SO2, SO3, and CO2. The deep understanding of analytes@CTF-0 complexation was acquired by interaction energy, NCI, QTAIM, SAPT0, EDD, NBO and FMO analyses. The outcome of interaction energy analyses clearly indicates that all the analytes are physiosorbed onto the CTF-0 surface. NCI and QTAIM analysis were employed to understand the nature of the non-covalent interactions. Furthermore, SAPT0 analysis revealed that dispersion has the highest contribution towards total SAPT0 energy. In NBO analysis, the highest charge transfer is obtained in the case of SO3@CTF-0 (-0.167 e-) whereas the lowest charge transfer is observed in CO2@CTF-0. The results of NBO charge transfer are also verified through EDD analysis. FMO analysis revealed that the highest reduction in the HOMO-LUMO energy gap is observed in the case of O3 (5.03 eV) adsorption onto the CTF-0 surface, which indicates the sensitivity of CTF-0 for O3 analytes. We strongly believe that these results might be productive for experimentalists to tailor a highly sensitive electrochemical sensor using covalent triazine-based frameworks (CTFs).

12.
Int J Mol Sci ; 22(21)2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34768868

RESUMO

2-deoxy-D-Ribose (2dDR) was first identified in 1930 in the structure of DNA and discovered as a degradation product of it later when the enzyme thymidine phosphorylase breaks down thymidine into thymine. In 2017, our research group explored the development of wound dressings based on the delivery of this sugar to induce angiogenesis in chronic wounds. In this review, we will survey the small volume of conflicting literature on this and related sugars, some of which are reported to be anti-angiogenic. We review the evidence of 2dDR having the ability to stimulate a range of pro-angiogenic activities in vitro and in a chick pro-angiogenic bioassay and to stimulate new blood vessel formation and wound healing in normal and diabetic rat models. The biological actions of 2dDR were found to be 80 to 100% as effective as VEGF in addition to upregulating the production of VEGF. We then demonstrated the uptake and delivery of the sugar from a range of experimental and commercial dressings. In conclusion, its pro-angiogenic properties combined with its improved stability on storage compared to VEGF, its low cost, and ease of incorporation into a range of established wound dressings make 2dDR an attractive alternative to VEGF for wound dressing development.


Assuntos
Desoxirribose/farmacologia , Fatores de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/efeitos dos fármacos , Indutores da Angiogênese/química , Animais , Bandagens/tendências , Fenômenos Fisiológicos Cardiovasculares/efeitos dos fármacos , Desoxirribose/metabolismo , Humanos , Morfogênese/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Fisiológica/fisiologia , Ribose/metabolismo , Ribose/farmacologia , Fatores de Crescimento do Endotélio Vascular/efeitos dos fármacos
13.
Cureus ; 13(7): e16298, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34405063

RESUMO

Introduction  Breast cancer is a major cause of mortality among females, worldwide. The present study was intended to evaluate the significance in the management of carcinoembryonic antigen (CEA) and cancer antigen 15-3 (CA15-3) in patients with breast cancer. Methodology A cohort study was conducted at the Jinnah Postgraduate Medical Center, Karachi, Pakistan from June 2020 to May 2021. All diagnosed cases of breast cancer who underwent surgical excision of tumor were eligible to partake. Patients who had metastatic breast cancer or had a recurrence were excluded. The patient's sociodemographic and clinical data were documented in a predefined pro forma. It included information about the age, sex, weight, as well as serum CEA and CA15-3. The CA15-3 and CEA levels for each patient were assessed by taking a 5ml blood sample and sending it to the laboratory for further workup. preoperatively on the second, seventh, and 28th postoperative days. Results A mean ± SD age of 52.6 ± 8.89 years was reported. Family history of breast cancer was positive in one-fourth of the patients. Nodal metastasis was negative in 114 (46.72%) patients. Three-fourth of patients had Stage II-IV with only a minority diagnosed with Stage I. The mean levels for CA15-3 in women with Stage I cancer was significantly lower on the seventh day and 28th postoperative day, compared to preoperative levels (p = 0.05). Similar associations were seen for stages II and III. Higher CEA levels were significantly associated with stage III breast cancer preoperatively (5.88 ng/ml, p = 0.05) compared to postoperative values. Conclusion The current study revealed that preoperative values of serum CEA and CA15-3 significantly reduced postoperatively. Moreover, patients with advanced cancers had significantly higher levels of both tumor markers than those with less advanced diseases. The current study highlighted the importance of regular assessment of serum CEA and CA15-3 in breast cancer patients. Both these biomarkers are substantially elevated in breast cancer patients, preoperatively. Determining the levels of serum CEA and CA15-3 pre- and postoperatively may determine the prognosis and aid in forming the most optimal patient care regime with respect to the stage and subtype of cancer.

14.
J Mol Graph Model ; 106: 107910, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33848947

RESUMO

Among noble gases, Helium and Neon have smaller size, high ionization potential and low polarizability due to which these two gases exhibit weak binding affinities toward any surface. Bartlet's discovery and subsequent similar successful discoveries of stable complexes of noble gases opened new avenues for the storage of noble gases particularly on the new surfaces and their interactions for the storage of these gases. Here, we report the adsorption of light noble gases on polycationic clusters. Our current work not only investigates the interaction behavior of He and Ne with (Sb7Te8)5+ cluster but also explores the saturation limit of the cluster for He and Ne. Stability of various complexes of He and Ne with cationic surfaces is determined by the calculation of their interaction energies which reveal that the adsorption of single and multiple atoms of noble gases at faces of double cubic cluster is comparatively more favorable than at the bond lengths. Electronic properties such as HOMO-LUMO gaps show that complexes of He and Ne are more stable electronically than that of pure cluster, because HOMO-LUMO gap of complexes are higher than the bare polycationic cluster. NCI analysis of iso-surfaces and RDG maps confirms the presence of van der Waals forces between light noble gases and polycationic clusters. Saturation studies reveal that cluster can adsorb eleven He and/or ten Ne atoms with no or minimum distortion in the geometry of cluster. The results showed that Ne has greater tendency to interact with polycationic clusters due to the large electronic cloud and polarizability value than He.


Assuntos
Gases , Gases Nobres , Adsorção , Humanos , Masculino , Neônio
15.
Phys Chem Chem Phys ; 23(14): 8557-8570, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33876018

RESUMO

The low concentration of graphene (<5%) in graphene/polypyrrole composites makes it quite challenging to devise a theoretical model for these composites. Thus, herein, we present theoretical calculations to determine the geometric electronic and optical properties of graphene/polypyrrole composites. Ribbon and sheet models of various sizes were considered for graphene. Oligopyrrole of various lengths was deposited in the graphene model in different orientations including π-stacking, tilted and vertical orientations. Theoretical calculations at the M062X/def2-SVP level revealed that π-stacking is the preferred orientation. To model a lower concentration of graphene, sandwich complexes of oligopyrrole were considered with graphene nanoribbons. Interaction energies revealed that sandwich complexes possessed superior additivity. The NCI analysis established that weak van der Waals interactions existed in all composites. Moreover, the HOMO-LUMO gap decreases as the concentration of graphene increases. Thus, the computed optical band gap of the C58H24-based composite is about 1.7 eV, which is consistent with the reported experimental value (2.1-1.81 eV). The computed band gap further decreases to ∼1.6 eV when the proportion of graphene increases to C64H26. Thus, our results for the graphene nanoribbon-based polypyrrole composites are in good agreement with experimental results. The UV/visible spectra revealed that as the concentration of graphene increases, a red shift is observed for all the configurations, which is consistent with experimental results.

16.
J Mol Graph Model ; 101: 107724, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32937278

RESUMO

Polyaniline emeraldine salt and Polyaniline Zinc Oxide composite are comprehensively studied to compare their sensing ability towards ammonia, acetone, methanol and ethanol. Sensing ability is evaluated through thermodynamic, geometric and electronic parameters. A number of orientations are evaluated in search for the lowest energy structure. The comparison of thermodynamic, geometric and electronic parameters of simple and composite sensors confirmed that composite sensor shows better sensing ability than simple PANI. Composite formation between polyaniline and zinc oxide is a thermodynamically feasible process with interaction energy of -42.8 kcal/mol. Both sensor shows highest interaction energy for ethanol among four analytes. Composite sensor shows almost twice the interaction with ethanol, methanol and acetone while 1.5 times the interaction energy for ammonia. The results of run simulations and subsequent calculations showed that in composite sensors, zinc oxide not only enhances the binding power of conducting polymer with analytes but also interacts directly with analytes. Strong hydrogen bonding as well as weak dispersion forces of attraction are responsible for the stability of composite and all complexes, as revealed by non-covalent interaction (NCI) studies. Acetone shows a different behaviour in composite sensor complex than other analytes.


Assuntos
Óxido de Zinco , Amônia , Compostos de Anilina , Polímeros
17.
J Biomed Mater Res B Appl Biomater ; 108(8): 3064-3075, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32619310

RESUMO

Scar free healing together with pain management is one of the major considerations in full thickness wound healing. Extensive wounds take longer to heal without any clinical intervention and, hence, need natural or artificial extracellular matrix support for quick skin regeneration. To address these issues, medicated 3D porous biomimetic scaffolds were developed with a unique combination of biopolymers, that is, chitosan, sodium alginate, and elastin, supplemented with a non-steroidal anti-inflammatory drug (NSAID). Scaffolds were physically characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), swelling ratio analysis, and degradation studies. Findings of the performed analyses proved that these skin substitutes suitable for skin tissue engineering applications attributable to their nano-microporous structures (pore size in range of 0.085-256 µm) allowing cell infiltration and high-water absorption capacity for management of wound exudates. Optimal dose of the loaded ibuprofen was estimated by evaluating effect of variable concentrations of ibuprofen (control, ILM-10, ILM-15, and ILM-20) on adipose tissue-derived mesenchymal stem cells (ASCs) proliferation rate. Out of all experimental groups, ILM-20 constructs were found to accelerate the proliferation rate of seeded ASCs confirming their non-cytotoxic characteristics as well potential to be used for translational scaffold-based therapies.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Nanoestruturas , Dermatopatias/terapia , Pele Artificial , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Anti-Inflamatórios não Esteroides/toxicidade , Biomimética , Bovinos , Ibuprofeno/administração & dosagem , Células-Tronco Mesenquimais , Microscopia Eletrônica de Varredura , Nanoestruturas/toxicidade , Porosidade , Ratos , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier , Cicatrização/efeitos dos fármacos
18.
Microvasc Res ; 131: 104035, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32593538

RESUMO

BACKGROUND: Delayed neovascularisation of tissue-engineered (TE) complex constructs is a major challenge that causes their failure post-implantation. Although significant progress has been made in the field of angiogenesis, ensuring rapid neovascularisation still remains a challenge. The use of pro-angiogenic agents is an effective approach to promote angiogenesis, and vascular endothelial growth factor (VEGF) has been widely studied both at the biological and molecular levels and is recognised as a key stimulator of angiogenesis. However, the exogenous use of VEGF in an uncontrolled manner has been shown to result in leaky, permeable and haemorrhagic vessels. Thus, researchers have been actively seeking alternative agents to upregulate VEGF production rather than exogenous use of VEGF in TE systems. We have previously revealed the potential of 2-deoxy-d-ribose (2dDR) as an alternative pro-angiogenic agent to induce angiogenesis and accelerates wound healing. However, to date, there is not any clear evidence on whether 2dDR influences the angiogenic cascade that involves VEGF. METHODS: In this study, we explored the angiogenic properties of 2dDR either by its direct application to human aortic endothelial cells (HAECs) or when released from commercially available alginate dressings and demonstrated that when 2dDR promotes angiogenesis, it also increases the VEGF production of HAECs. RESULTS: The VEGF quantification results suggested that VEGF production by HAECs was increased with 2dDR treatment but not with other sugars, including 2-deoxy-l-ribose (2dLR) and d-glucose (DG). The stability studies demonstrated that approximately 40-50% of the 2dDR had disappeared in the media over 14 days, either in the presence or absence of HAECs, and the reduction was higher when cells were present. The concentration of VEGF in the media also fell after day 4 associated with the reduction in 2dDR. CONCLUSION: This study suggests that 2dDR (but not other sugars tested in this study) stimulates angiogenesis by increasing the production of VEGF. We conclude 2dDR appears to be a practical and effective indirect route to upregulating VEGF for several days, leading to increased angiogenesis.


Assuntos
Indutores da Angiogênese/farmacologia , Membrana Corioalantoide/irrigação sanguínea , Desoxirribose/farmacologia , Células Endoteliais/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Alginatos/química , Indutores da Angiogênese/química , Animais , Células Cultivadas , Embrião de Galinha , Preparações de Ação Retardada , Desoxirribose/química , Portadores de Fármacos , Estabilidade de Medicamentos , Células Endoteliais/metabolismo , Humanos , Transdução de Sinais , Regulação para Cima
19.
Bioorg Chem ; 100: 103876, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32388426

RESUMO

Over expression of thymidine phosphorylase (TP) in various human tumors compared to normal healthy tissue is associated with progression of cancer and proliferation. The 2-deoxy-d-ribose is the final product of thymidine phosphorylase (TP) catalyzed reaction. Both TP and 2-deoxy-d-ribose are known to promote unwanted angiogenesis in cancerous cells. Discovery of potent inhibitors of thymidine phosphorylase (TP) can offer appropriate approach in cancer treatment. A series of ciprofloxacin 2, 3a-3c, 4a-4d, 5a-5b, 6 and 7 has been synthesized and characterized using spectroscopic techniques. Afterwards, inhibitory potential of synthesized ciprofloxacin 2, 3a-3c, 4a-4d, 5a-5b, 6 and 7 against thymidine phosphorylase enzyme was assessed. Out of these twelve analogs of ciprofloxacin nine analogues 3a-3c, 4a-4c, 5a-5b and 6 showed good inhibitory activity against thymidine phosphorylase. Inhibitory activity as presented by their IC50 values was found in the range of 39.71 ± 1.13 to 161.89 ± 0.95 µM. The 7-deazaxanthine was used as a standard inhibitor with IC50 = 37.82 ± 0.93 µM. Furthermore, the chick chorionic allantoic membrane (CAM) assay was used to investigate anti-angiogenic activity of the most active ciprofloxacin-based inhibitor 3b. To enlighten the important binding interactions of ciprofloxacin derivatives with target enzyme, the structure activity relationship and molecular docking studies of chosen ciprofloxacin analogues was discussed. Docking studies revealed key π-π stacking, π-cation and hydrogen bonding interactions of ciprofloxacin analogues with active site residues of thymidine phosphorylase enzyme.


Assuntos
Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Ciprofloxacina/análogos & derivados , Ciprofloxacina/farmacologia , Timidina Fosforilase/antagonistas & inibidores , Inibidores da Angiogênese/síntese química , Animais , Antibacterianos/síntese química , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Embrião de Galinha , Ciprofloxacina/síntese química , Reposicionamento de Medicamentos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Simulação de Acoplamento Molecular , Timidina Fosforilase/metabolismo
20.
J Tissue Eng Regen Med ; 14(7): 973-988, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32473079

RESUMO

The absorption capacity of cotton dressings is a critical factor in their widespread use where they help absorb wound exudate. Cotton wax dressings, in contrast, are used for wounds where care is taken to avoid adhesion of dressings to sensitive wounds such as burn injuries. Accordingly, we explored the loading of 2-deoxy-D-ribose (2dDR), a small sugar, which stimulates angiogenesis and wound healing in normal and diabetic rats, into both types of dressings and measured the release of it over several days. The results showed that approximately 90% of 2dDR was released between 3 and 5 days when loaded into cotton dressings. For wax-coated cotton dressings, several methods of loading of 2dDR were explored. A strategy similar to the commercial wax coating methodology was found the best protocol which provided a sustained release over 5 days. Cytotoxicity analysis of 2dDR loaded cotton dressing showed that the dressing stimulated metabolic activity of fibroblasts over 7 days confirming the non-toxic nature of this sugar-loaded dressings. The results of the chick chorioallantoic membrane (CAM) assay demonstrated a strong angiogenic response to both 2dDR loaded cotton dressing and to 2dDR loaded cotton wax dressings. Both dressings were found to increase the number of newly formed blood vessels significantly when observed macroscopically and histologically. We conclude this study offers a simple approach to developing affordable wound dressings as both have the potential to be evaluated as pro-active dressings to stimulate wound healing in wounds where management of exudate or prevention of adherence to the wounds are clinical requirements.


Assuntos
Indutores da Angiogênese , Bandagens , Fibra de Algodão , Desoxirribose , Teste de Materiais , Neovascularização Fisiológica/efeitos dos fármacos , Indutores da Angiogênese/química , Indutores da Angiogênese/farmacologia , Animais , Embrião de Galinha , Membrana Corioalantoide/metabolismo , Desoxirribose/química , Desoxirribose/farmacologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/terapia , Camundongos , Células NIH 3T3 , Ratos , Cicatrização
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