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1.
Angew Chem Int Ed Engl ; 62(16): e202215595, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-36789879

RESUMEN

The design of metal-organic frameworks (MOFs) having large pore sizes and volumes often requires the use of complex organic ligands, currently synthesized using costly and time-consuming palladium-catalyzed coupling chemistry. Thus, in the present work, a new strategy for ligand design is reported, where piperazine and dihydrophenazine units are used as substitutes for benzene rings, which are the basic building block of most MOF ligands. This chemistry, which is based on simple, nucleophilic aromatic substitution (SN Ar) reactions, is used for the transition metal catalyst-free construction of 21 new, carboxylate-based ligands with varying sizes, shapes, and denticity and 15 linear di- and tetra-nitriles. Moreover, to demonstrate the utility of the ligands as building blocks, 16 new structurally diverse MOFs having surface areas up to 3100 m2 g-1 were also synthesized.

2.
Med J Islam Repub Iran ; 32: 135, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30815430

RESUMEN

Background: PI3K/Akt/mTOR pathway is a crucial pathway in the angiogenesis, tumour growth and cell differentiation of several cancers. The PI3K and KIT genes are key genes of this pathway. Previous studies have reported the importance of these genes in the development of gastrointestinal carcinoma, leukaemia, and melanomas. The role of mutations and overexpression of PI3K and KIT genes in breast cancer has been previously proved. This study investigates the correlation between PI3K and KIT gene mutations in sporadic breast cancer. Methods: Multiplex Ligation-dependent Probe Amplification (MLPA) technique was used to determine the Copy Number Variation (CNV) of PI3K and KIT genes in 34 breast cancer tumours and PCR-sequencing was used to detect the mutation in PI3K exons 9 and 20. Results: Our results reported that 27% of patients had CNV of the KIT gene; whereas, 20% and 17.5% of patients, had mutation and CNV in the PI3K gene, respectively. We did not found a significant correlation between the mutations of PI3K and KIT genes. Conclusion: About two-tenth of the patients revealed CNV and lesser than two-tenth indicated mutation in the PI3K gene, whereas one-third of the patients demonstrated CNV in the KIT gene. Thus, administration of the PI3K and KIT gene inhibitor drugs might be proposed to suppress breast cancer in patients with mutation and CNV of each of these individual genes.

3.
ACS Omega ; 9(17): 19071-19076, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38708203

RESUMEN

Radioactive iodine poses a significant risk to human health, particularly with regard to reproductive and metabolic functions. Designing and developing highly efficient adsorbent materials for radioactive substances remain a significant challenge. This study aimed to address this issue by the fabricating polymeric beads containing covalent organic polymer (COP) as an effective method for removing iodine vapor. To achieve this, a COP was first synthesized via the Friedel-Crafts reaction catalyzed by anhydrous aluminum chloride. Then, COP-loaded polysulfone (PSf) (COP@PSf) and PSf beads were prepared using a phase separation method. The beads produced in this research have exhibited remarkable proficiency in adsorbing iodine vapor, showing an adsorption capacity of up to 216 wt % within just 420 min, which is higher than that of most other similar beads reported in the literature.

4.
Carbohydr Polym ; 195: 413-419, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29804994

RESUMEN

An acidic ionic liquid (IL), i.e. 1-(carboxymethyl)pyridinium chloride, is synthesized and investigated for its untapped potential to dissolve cellulose, chitosan and chitin with concentrations of up to 11, 10 and 5 wt.%, respectively. Interestingly, the optimum water content of the IL/water towards efficient dissolution is determined to be as high as 40 wt.%, which is in evident contrast to the previous reports for other ILs by which the dissolution of polysaccharides is achieved at the expense of water content. Using high water content in IL/water mixture makes a breakthrough in ease of solution processability and dissolution cost reduction. Regenerated cellulose and chitosan have less crystallinity and lower temperature of thermal degradation onset (Tons) compared to the initial samples. The regenerated cellulose exhibits reduction in degree of polymerization, crystallinity and Tons by 55.1%, 11.0% and 38.2%, respectively. Chitin in addition to dissolution, is also hydrolyzed to quaternary ammonium chitosan.

5.
Iran J Pathol ; 13(4): 447-453, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30774684

RESUMEN

BACKGROUND AND OBJECTIVE: The PI3K/AKT/mTOR pathway is known to play an important role in regulating angiogenesis both in normal and breast cancer (BC) tissues. PIK3CA amplification was reported in various malignancies, including approximately 10% of BC cases. The aim of this study was to identify the frequency of PIK3CA amplification in Iranian female patients suffering from BC. Additionally, possible association between PIK3CA amplification and P110α expression with microvascular density (MVD) was examined. METHODS: DNA samples were extracted from paraffin embedded tumor tissue blocks and copy number changes were evaluated by MLPA Technique. The results were analyzed by coffalyzer software. The tissue expression of P110α and CD34 was assessed using immunohistochemistry. RESULTS: Ten out of 40 samples (17.5%) showed amplification in PIK3CA gene and 22 out of 40 samples (55%) showed overexpression in P110α. For CD34, from 40 samples, 20 (50%), 15 (37.5%) and 5 (12.5%) had scores 1+, 2+ and 3+, respectively. CONCLUSION: No significant association was detected between gain of PIK3CA copy number and P110α or CD34 tissue expression.

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