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1.
Opt Lett ; 49(7): 1721-1724, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38560846

RESUMO

The intricate spectrally resolved optical nonlinearities resulting from a spectrally broad femtosecond Gaussian laser pulse have been unraveled using a single-scan and spectrometer-based nonlinear optical probing technique. The interaction of the broad femtosecond laser pulse with a strongly absorbing organic dye has unveiled a remarkably distinct nonlinear absorption behavior across the broad spectral window. The nonlinear absorption behavior unveils an unusual transition from the reverse saturation absorption (RSA) to the saturation absorption (SA) as we sweep the wavelength on both sides of the central wavelength of the excitation laser pulse. A competition between the band-filling and excited-state absorption results in such a dramatic switch-over from the RSA to the SA due to the variation of the intensity distribution across the Gaussian pulse spectrum. On the other hand, the nonlinear refraction studies dictate more over the constant Kerr-type positive nonlinear refractive indices across the entire laser pulse, with a pronounced contribution from the nonlinear absorption phase dominating at the center of the pulse. The presented technique establishes a robust and simple spectrometer-based technique that offers new, to the best of our knowledge, avenues for estimating optical nonlinearities for rapid nonlinear optical measurements.

2.
Langmuir ; 40(10): 5401-5408, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38426862

RESUMO

Increasing carbon dioxide emissions has sparked a growing interest in capturing these emissions at the source of their release. For such processes, amines can be used as carbon dioxide capture agents. Herein, CO2 was captured under ambient conditions using solutions of amines and polyamines in ethylene glycol. The captured solutions were then successfully hydrogenated to methanol under hydrogen pressure with a heterogeneous Cu/ZnO/Al2O3 industrial catalyst. An extensive amine scope found that tetramethyl-1,6-hexanediamine, with two tertiary amine sites, provided the highest methanol productivity. This reaction was then optimized to achieve up to 89% methanol yield under relatively mild conditions of 250 °C and 80 bar H2 pressure. The catalyst was shown to be recyclable over five reaction cycles.

3.
Phys Chem Chem Phys ; 26(21): 15125-15129, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38764422

RESUMO

The strong two-photon induced nonlinear absorption and self-focusing type positive nonlinear refraction are pronounced by the structural engineering in ß-functionalized cobalt corroles.

4.
Mol Cancer ; 22(1): 1, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36597126

RESUMO

BACKGROUND: Small cell lung cancer (SCLC) is an aggressive lung cancer subtype that is associated with high recurrence and poor prognosis. Due to lack of potential drug targets, SCLC patients have few therapeutic options. MicroRNAs (miRNAs) provide an interesting repertoire of therapeutic molecules; however, the identification of miRNAs regulating SCLC growth and metastasis and their precise regulatory mechanisms are not well understood. METHODS: To identify novel miRNAs regulating SCLC, we performed miRNA-sequencing from donor/patient serum samples and analyzed the bulk RNA-sequencing data from the tumors of SCLC patients. Further, we developed a nanotechnology-based, highly sensitive method to detect microRNA-1 (miR-1, identified miRNA) in patient serum samples and SCLC cell lines. To assess the therapeutic potential of miR-1, we developed various in vitro models, including miR-1 sponge (miR-1Zip) and DOX-On-miR-1 (Tet-ON) inducible stable overexpression systems. Mouse models derived from intracardiac injection of SCLC cells (miR-1Zip and DOX-On-miR-1) were established to delineate the role of miR-1 in SCLC metastasis. In situ hybridization and immunohistochemistry were used to analyze the expression of miR-1 and target proteins (mouse and human tumor specimens), respectively. Dual-luciferase assay was used to validate the target of miR-1, and chromatin immunoprecipitation assay was used to investigate the protein-gene interactions. RESULTS: A consistent downregulation of miR-1 was observed in tumor tissues and serum samples of SCLC patients compared to their matched normal controls, and these results were recapitulated in SCLC cell lines. Gain of function studies of miR-1 in SCLC cell lines showed decreased cell growth and oncogenic signaling, whereas loss of function studies of miR-1 rescued this effect. Intracardiac injection of gain of function of miR-1 SCLC cell lines in the mouse models showed a decrease in distant organ metastasis, whereas loss of function of miR-1 potentiated growth and metastasis. Mechanistic studies revealed that CXCR4 is a direct target of miR-1 in SCLC. Using unbiased transcriptomic analysis, we identified CXCR4/FOXM1/RRM2 as a unique axis that regulates SCLC growth and metastasis. Our results further showed that FOXM1 directly binds to the RRM2 promoter and regulates its activity in SCLC. CONCLUSIONS: Our findings revealed that miR-1 is a critical regulator for decreasing SCLC growth and metastasis. It targets the CXCR4/FOXM1/RRM2 axis and has a high potential for the development of novel SCLC therapies. MicroRNA-1 (miR-1) downregulation in the tumor tissues and serum samples of SCLC patients is an important hallmark of tumor growth and metastasis. The introduction of miR-1 in SCLC cell lines decreases cell growth and metastasis. Mechanistically, miR-1 directly targets CXCR4, which further prevents FOXM1 binding to the RRM2 promoter and decreases SCLC growth and metastasis.


Assuntos
Neoplasias Pulmonares , MicroRNAs , Carcinoma de Pequenas Células do Pulmão , Humanos , Animais , Camundongos , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Neoplasias Pulmonares/patologia , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Proteína Forkhead Box M1/genética , Receptores CXCR4/genética , Receptores CXCR4/metabolismo
5.
Chemistry ; 29(59): e202301486, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37485580

RESUMO

Low-valent main group compounds that fluoresce in the solid-state were previously unknown. To address this, we investigated room-temperature photoluminescence from a series of crystals of germylenes 3-8 in this article; they exhibited emissions nearly reaching the NIR. Germylene carboxylates (3-8) were synthesized by reacting dipyrromethene stabilized germylene pyrrolide (2) with carboxylic acids such as acetic acid, trifluoroacetic acid, benzoic acid, p-cyanobenzoic acid, p-nitrobenzoic acid, and acetylsalicylic acid.

6.
Cell Mol Neurobiol ; 43(7): 3479-3495, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37193907

RESUMO

Repeated mild traumatic brain injuries (rMTBI) affect mitochondrial homeostasis in the brain. However, mechanisms of long-lasting neurobehavioral effects of rMTBI are largely unknown. Mitofusin 2 (Mfn2) is a critical component of tethering complexes in mitochondria-associated membranes (MAMs) and thereby plays a pivotal role in mitochondrial functions. Herein, we investigated the implications of DNA methylation in the Mfn2 gene regulation, and its consequences on mitochondrial dysfunction in the hippocampus after rMTBI. rMTBI dramatically reduced the mitochondrial mass, which was concomitant with decrease in Mfn2 mRNA and protein levels. DNA hypermethylation at the Mfn2 gene promoter was observed post 30 days of rMTBI. The treatment of 5-Azacytidine, a pan DNA methyltransferase inhibitor, normalized DNA methylation levels at Mfn2 promoter, which further resulted into restoration of Mfn2 function. The normalization of Mfn2 function was well correlated with recovery in memory deficits in rMTBI-exposed rats. Since, glutamate excitotoxicity serves as a primary insult after TBI, we employed in vitro model of glutamate excitotoxicity in human neuronal cell line SH-SY5Y to investigate the causal epigenetic mechanisms of Mfn2 gene regulation. The glutamate excitotoxicity reduced Mfn2 levels via DNA hypermethylation at Mfn2 promoter. Loss of Mfn2 caused significant surge in cellular and mitochondrial ROS levels with lowered mitochondrial membrane potential in cultured SH-SY5Y cells. Like rMTBI, these consequences of glutamate excitotoxicity were also prevented by 5-AzaC pre-treatment. Therefore, DNA methylation serves as a vital epigenetic mechanism involved in Mfn2 expression in the brain; and this Mfn2 gene regulation may play a pivotal role in rMTBI-induced persistent cognitive deficits. Closed head weight drop injury method was employed to induce repeated mild traumatic brain (rMTBI) in jury in adult, male Wistar rats. rMTBI causes hyper DNA methylation at the Mfn2 promoter and lowers the Mfn2 expression triggering mitochondrial dysfunction. However, the treatment of 5-azacytidine normalizes DNA methylation at the Mfn2 promoter and restores mitochondrial function.


Assuntos
Lesões Encefálicas Traumáticas , Neuroblastoma , Animais , Masculino , Ratos , Azacitidina/farmacologia , Encéfalo/metabolismo , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/genética , Lesões Encefálicas Traumáticas/metabolismo , DNA/metabolismo , Metilação de DNA , Glutamatos/metabolismo , Transtornos da Memória/etiologia , Mitocôndrias/metabolismo , Ratos Wistar
7.
Chem Rec ; 23(9): e202300104, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37212421

RESUMO

In the last few years, many reagents and protocols have been developed to allow for the efficient fluorofunctionalization of a diverse set of scaffolds ranging from alkanes, alkenes, alkynes, and (hetero)arenes. The concomitant rise of organofluorine chemistry and visible light-mediated synthesis have synergistically expanded the fields and have mutually benefitted from developments in both fields. In this context, visible light driven formations of radicals containing fluorine have been a major focus for the discovery of new bioactive compounds. This review details the recent advances and progress made in visible light-mediated fluoroalkylation and heteroatom centered radical generation.

8.
J Org Chem ; 88(2): 1194-1199, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36622772

RESUMO

An efficient method for the direct C(sp)-H difluoromethylation of terminal alkynes and the desilylation-difluoromethylation of (trimethylsilyl)acetylenes is disclosed. The copper-catalyzed transformation provides access to a wide range of structurally diverse CF2H alkynes in good yields, utilizing a (difluoromethyl)zinc reagent and an organic oxidant. The difluoromethylation of important synthons and API's is showcased. The synthetic utility of these (difluoromethyl)alkynes is demonstrated by selected cycloaddition reactions. Additionally, a slight modification to the reaction conditions allowed the selective preparation of a 2-difluoromethylindole.

9.
Scand J Rheumatol ; 52(3): 306-316, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36763458

RESUMO

Aortic involvement in immunoglobulin G4-related disease (IgG4-RD) is extremely rare and is often overlooked during the aortitis work-up. IgG4-related aortitis differs from non-IgG4-related aortitis in its histopathological features, site of involvement, laboratory markers, and treatment options. The histopathological examination of the vessel walls characteristically reveals adventitial thickening with intimal sparing, typically affecting the infrarenal abdominal aorta. In addition, inadequate knowledge about the disease often leads to delayed or missed diagnosis and undermanagement of a potentially treatable condition. Hence, in this paper, we review the unique clinical manifestations, laboratory markers, diagnostic features, current treatment strategies, and novel experimental therapeutic options in the management of IgG4-related aortitis.


Assuntos
Aortite , Doença Relacionada a Imunoglobulina G4 , Humanos , Aortite/diagnóstico , Aortite/patologia , Doença Relacionada a Imunoglobulina G4/diagnóstico , Imunoglobulina G , Biomarcadores
10.
Inorg Chem ; 62(32): 12895-12904, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37523680

RESUMO

Optical nonlinearities of discrete absorption energy levels of one of the typical heterocyclic aromatic molecules, free-base porphyrins, have been probed over a broad spectral region (400-1600 nm) utilizing intense femtosecond pulses. A wide range of strong one- and multiphoton-induced nonlinear absorptions of both the blue-end Soret (B) band (au → b1g) and red-end orbital mixing split quasi-allowed Q-bands (Qx(0,0; 0,1), Qy(0,0; 0,1), au → eg) are critically probed and reported. During the resonant excitation within B- (400 nm) and Q-bands (600-750 nm), the nonlinear absorption has become predominant by the saturation of absorption (SA) of the one-photon absorption (1PA) process due to ground-state bleaching. At nonresonant wavelengths, it is dominated by the reverse saturation of absorption (RSA), involving various nonlinear processes of two-, three-, and four-photon (2PA, 3PA, and 4PA) absorptions, either to B- or Q-bands (1100-1600 nm). The laser intensity-dependent nonresonant (2PA, 800 nm) excitations for the prominent B-band show a distinct cross-over from SA to RSA, contributed by the excited-state absorption (ESA) utilizing a three-photon induced (3PA) process, whereas resonant (1PA, 400 nm) excitation reveals a systematic strong SA process. Both wavelength- and intensity-dependent nonlinear refractive index studies exhibit positive electronic Kerr-based self-focusing effects, with prominent contributions of nonlinear absorption and higher-order effects. The spectrally discrete, highly intense laser probing of individual energy bands and the consequent variety of nonlinearities can be broadly generalized for many free-base porphyrins and metalloporphyrins. The present studies provide a strong foundation and new insight into the broad categories of macrocycles, such as porphyrins and phthalocyanines, for myriad applications in nonlinear optics and bio/optophotonics.

11.
Phys Chem Chem Phys ; 25(8): 6131-6141, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36752117

RESUMO

Upconversion materials have attracted considerable research interest for their application in bioimaging due to their unique optical properties. NaREF4 (RE = Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) based host lattice, which is widely used for upconversion, requires expensive rare-earth elements and tedious reaction conditions. Hence there is a need to develop environmentally friendly and cost effective materials for upconversion. In this study, we propose NaBiF4 as a host material for upconversion which is based on environmentally friendly and cost-effective bismuth. NaBiF4 has not been explored as an imaging probe before. We report efficient Yb3+/Tm3+ doped NaBiF4 based upconversion submicron particles which exhibit a photostable, wide upconversion emission range (NIR-to-NIR and Vis) under NIR (980 nm) excitation, and in-vitro non-cytotoxic uptake by mammalian cancer cell lines as well as bacterial cells with a high signal to background ratio. The synthesis of the chosen host material co-doped with Yb3+/Tm3+ has not been reported earlier through such a non-aqueous quaternary reverse micelle route. Here, we functionally validate these submicron particles as viable alternatives to currently available upconversion nanomaterials and highlight their potential as luminescent probes for bioimaging.


Assuntos
Metais Terras Raras , Nanoestruturas , Animais , Luminescência , Mamíferos
12.
Ann Noninvasive Electrocardiol ; 28(3): e13051, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36811259

RESUMO

AIMS: To summarize published case reports of patients diagnosed with coronavirus disease 2019 (COVID-19) and Brugada pattern electrocardiogram (ECG). METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist were followed. A literature search was conducted using PubMed, EMBASE, and Scopus up until September 2021. The incidence, clinical characteristics, and management outcomes of COVID-19 patients with a Brugada pattern ECG were identified. RESULTS: A total of 18 cases were collected. The mean age was 47.1 years and 11.1% were women. No patients had prior confirmed diagnosis of Brugada syndrome. The most common presenting clinical symptoms were fever (83.3%), chest pain (38.8%), shortness of breath (38.8%), and syncope (16.6%). All 18 patients presented with type 1 Brugada pattern ECG. Four patients (22.2%) underwent left heart catheterization, and none demonstrated the presence of obstructive coronary disease. The most common reported therapies included antipyretics (55.5%), hydroxychloroquine (27.7%), and antibiotics (16.6%). One patient (5.5%) died during hospitalization. Three patients (16.6%) who presented with syncope received either an implantable cardioverter defibrillator or wearable cardioverter defibrillator at discharge. At follow-up, 13 patients (72.2%) had resolution of type 1 Brugada pattern ECG. CONCLUSION: COVID-19-associated Brugada pattern ECG seems relatively rare. Most patients had resolution of the ECG pattern once their symptoms have improved. Increased awareness and timely use of antipyretics is warranted in this population.


Assuntos
Antipiréticos , Síndrome de Brugada , COVID-19 , Desfibriladores Implantáveis , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Eletrocardiografia/efeitos adversos , COVID-19/complicações , Síndrome de Brugada/complicações , Síndrome de Brugada/diagnóstico , Síndrome de Brugada/terapia , Desfibriladores Implantáveis/efeitos adversos , Síncope/etiologia
13.
J Postgrad Med ; 69(2): 108-110, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36891941

RESUMO

Littoral cell angioma (LCA) is a rare benign tumor originating exclusively from the venous sinus lining cells of the splenic red pulp. These cells are unique in having a distinctive hybrid endothelial/histiocytic phenotype. Also, there are reports of the association of LCA with internal malignancies. We present a case report highlighting an unusual association of LCA with conventional renal cell carcinoma (RCC), masquerading as a metastatic lesion. Knowledge of such an association is necessary to avoid misdiagnosis and prevent potential overtreatment.


Assuntos
Carcinoma de Células Renais , Hemangioma , Neoplasias Renais , Neoplasias Esplênicas , Humanos , Carcinoma de Células Renais/complicações , Carcinoma de Células Renais/cirurgia , Neoplasias Esplênicas/complicações , Neoplasias Esplênicas/cirurgia , Neoplasias Esplênicas/diagnóstico , Hemangioma/complicações , Hemangioma/diagnóstico , Hemangioma/patologia
14.
Int J Mol Sci ; 24(22)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38003271

RESUMO

Pusa Basmati 1509 (PB1509) is one of the major foreign-exchange-earning varieties of Basmati rice; it is semi-dwarf and early maturing with exceptional cooking quality and strong aroma. However, it is highly susceptible to various biotic stresses including bacterial blight and blast. Therefore, bacterial blight resistance genes, namely, xa13 + Xa21 and Xa38, and fungal blast resistance genes Pi9 + Pib and Pita were incorporated into the genetic background of recurrent parent (RP) PB1509 using donor parents, namely, Pusa Basmati 1718 (PB1718), Pusa 1927 (P1927), Pusa 1929 (P1929) and Tetep, respectively. Foreground selection was carried out with respective gene-linked markers, stringent phenotypic selection for recurrent parent phenotype, early generation background selection with Simple sequence repeat (SSR) markers, and background analysis at advanced generations with Rice Pan Genome Array comprising 80K SNPs. This has led to the development of Near isogenic lines (NILs), namely, Pusa 3037, Pusa 3054, Pusa 3060 and Pusa 3066 carrying genes xa13 + Xa21, Xa38, Pi9 + Pib and Pita with genomic similarity of 98.25%, 98.92%, 97.38% and 97.69%, respectively, as compared to the RP. Based on GGE-biplot analysis, Pusa 3037-1-44-3-164-20-249-2 carrying xa13 + Xa21, Pusa 3054-2-47-7-166-24-261-3 carrying Xa38, Pusa 3060-3-55-17-157-4-124-1 carrying Pi9 + Pib, and Pusa 3066-4-56-20-159-8-174-1 carrying Pita were identified to be relatively stable and better-performing individuals in the tested environments. Intercrossing between the best BC3F1s has led to the generation of Pusa 3122 (xa13 + Xa21 + Xa38), Pusa 3124 (Xa38 + Pi9 + Pib) and Pusa 3123 (Pi9 + Pib + Pita) with agronomy, grain and cooking quality parameters at par with PB1509. Cultivation of such improved varieties will help farmers reduce the cost of cultivation with decreased pesticide use and improve productivity with ensured safety to consumers.


Assuntos
Oryza , Humanos , Melhoramento Genético , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Melhoramento Vegetal , Marcadores Genéticos
15.
Angew Chem Int Ed Engl ; 62(30): e202304294, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37235718

RESUMO

N-(difluoromethyl)amino (-NCF2 H) compounds are of great interest given their unique and underexplored physiochemical properties. The lack of structural diversity in NCF2 H compounds is likely due in part to the shortage of protocols for efficient installation. Presented herein is a new shelf-stable pyridinium reagent that enables the direct installation of the N-(difluoromethyl)sulfonamide moiety [N(Ts)CF2 H)] onto (hetero)arenes and alkenes for the diversification of aryl and alkyl NCF2 H compounds. The described protocol utilizes blue light photoredox catalysis and displays broad functional group tolerance with excellent chemoselectivity. Additional transformations and applicability towards a photoredox continuous flow protocol are also demonstrated.

16.
Chemistry ; 28(41): e202200457, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35605186

RESUMO

A convenient method for the direct ipso-phosphonodifluoromethylation of arylboronic acids via nickel-copper co-catalysis is disclosed. This work, which utilizes inexpensive first row transition metals, represents a facile alternative to the traditional palladium catalyzed approach. The method utilizes inexpensive commodity chemicals and substrates while tolerating a variety of biologically relevant functional groups. Structurally diverse phosphonodifluoromethylarenes are furnished in good yields under short reaction times. Control experiments to probe possible reaction pathways are also included.


Assuntos
Cobre , Níquel , Ácidos Borônicos , Catálise , Estrutura Molecular , Paládio
17.
Inorg Chem ; 61(3): 1297-1307, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34882407

RESUMO

A series of ß-TCBD (1,1,4,4-tetracyano-buta-1,3-diene)-appended porphyrins, M-TCBD (M = 2H, Co(II), Ni(II), Cu(II), and Zn(II)), was synthesized from 2,3-diphenylethynyl-12-nitro-meso-tetraphenylporphyrin, H2-PE2, and characterized by various spectroscopic techniques and electrochemical studies. The reaction proceeds via [2 + 2] cycloaddition and retroelectrocyclization reactions of tetracyanoethylene (TCNE) with H2-PE2. The observed unusual reduction potentials in the cyclic voltammograms of the synthesized porphyrins in the range of -0.06 to -0.10 V are the consequence of the TCBD moiety present at the ß-position of the porphyrin macrocycle. Notably, these porphyrins exhibited three porphyrin ring-centered reductions due to extended π-conjugation. The higher nonlinear optical response exhibited by the M-TCBD series as compared to the precursor (H2-PE2) was attributed to the existence of intramolecular charge transfer and enhanced polarization in the M-TCBD series. The single-beam femtosecond Z-scan measurements were performed to elucidate the third-order nonlinear optical properties, and the temporal response of these porphyrin molecules was investigated using optical pump-probe spectroscopy to study the excited state absorption dynamics. Z-scan measurements revealed that Co-TCBD exhibited a higher nonlinear optical response as compared to free base porphyrins. The two-photon absorption coefficient (ß) and the imaginary part of third-order nonlinear optical susceptibility (χ(3)) were obtained from the open aperture experiment, whereas the close aperture experiment delivered the magnitude and the sign of the nonlinear refractive index (n2) and the real part of χ(3). Furthermore, the femtosecond transient absorption spectroscopy revealed a faster relaxation dynamics of various absorption processes in a picosecond timescale. The excellent optical limiting threshold (1.90-2.33 × 1015 W/m2) of the synthesized porphyrins makes them good materials for laser protection and high-power laser operation.

18.
Inorg Chem ; 61(48): 19289-19301, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36403252

RESUMO

A new series of nonplanar and unsymmetrically ß-functionalized "push-pull" copper corroles, CuTPC(CHO)R7 [R = H, Br, Ph, Me, or 2-thienyl (Th)], were synthesized and characterized to elucidate the effect of ß-functionalization and nonplanarity on the photophysical, redox, and nonlinear optical (NLO) properties on the corrole ring. The synthetic route to unsymmetrically ß-octasubstituted copper corroles includes bromination of CuTPC(CHO) to get CuTPC(CHO)Br7 in 80% yield, which was further subjected to the Pd-catalyzed Suzuki reaction. CuTPC(CHO)Br7 exhibited a large red shift in the Soret band (Δλmax = 35-40 nm) and both the Q bands (Δλmax = 10-50 nm), as compared to CuTPC and CuTPC(CHO). CuTPC(CHO)Br7 was 510 and 290 mV anodically shifted in the first oxidation and the first reduction compared to CuTPC owing to the strong -I effect of CHO and Br groups. Density functional theory studies revealed that all the ß-octasubstituted copper corroles exhibited highly nonplanar saddle-shape conformation of the corrole ring. Very high torsional saddling was observed for CuTPC(CHO)Th7 (79-83°) than that for CuTPC (49-53°), even larger than that for CuTPCBr8 (67-70°). Femtosecond laser-induced third-order NLO studies from these copper corroles showed strong two-photon absorption cross-sections (0.48-6.98 × 104 GM) and self-focusing-type positive nonlinear refraction behavior. The observed structure-dependent two-photon absorption coefficients (ß) are in the range of ∼2.7-20.9 × 10-12 m/W, and the n2 values are in the range of ∼0.64-6.45 × 10-18 m2/W. The present results may facilitate a new window for these copper corroles in nonlinear optical devices, femtosecond optical limiters, and many other ultrafast photonic applications.

19.
Inorg Chem ; 61(26): 9968-9982, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35729686

RESUMO

Two new series of unsymmetrically ß-functionalized porphyrins, MTPP(NO2)MA (1M), (MA = methyl acrylate) and MTPP(NO2)MB (2M) (MB = mono-benzo) (where M = 2H, Co(II), Ni(II), Cu(II) and Zn(II)), were synthesized and characterized by various spectroscopic techniques. The saddle shape conformation of ZnTPP(NO2)MAPy and ZnTPP(NO2)MB was confirmed by single-crystal X-ray analysis. Density functional theory (DFT) calculation revealed that NiTPP(NO2)MB has a severe nonplanar geometry possessing a high magnitude of ΔCß = ±0.727 Å and Δ24 = ±0.422 Å values among all other porphyrins. Synthesized ß-substituted porphyrins exhibited red-shifted B- and Q-bands corresponding to their parent molecule due to the electron-withdrawing peripheral substituents. Notable redshift (Δλmax = 50-60 nm) in electronic spectral features and with weak-intensity emission spectral features were observed for the free-base porphyrins and Zn(II) complexes compared to H2TPP and ZnTPP, respectively. The first-ring reduction potential of MTPP(NO2)MA (1M) exhibited 0.21-0.5 V anodic shift, whereas 0.18-0.23 V anodic shift was observed in the first-ring oxidation potential compared to the corresponding MTPPs due to the presence of electron-withdrawing ß-substituents at the periphery of the macrocycle. Interestingly, NiTPP(NO2)MA (1Ni) has shown an additional NiII/NiIII oxidation potential observed at 2.05 V along with two ring-centered oxidations. The first-ring reduction and oxidation potentials of MTPP(NO2)MB (2M) have shown 0.39-0.46 and 0.19-0.27 V anodic shifts with respect to their corresponding MTPPs. The nonlinear optical (NLO) properties of all of the porphyrins were investigated, and the extracted nonlinear optical parameters revealed intense reverse-saturable absorption (RSA) behavior and the self-focusing behavior with positive nonlinear refractive index in the range of (0.19-1.75) × 10-17 m2/W. Zn(II) complexes exhibited the highest two-photon absorption coefficient (ß) and cross section (σTPA) of ∼95 × 10-12 m/W and 19.66 × 104 GM, respectively, among all of the metal complexes.

20.
J Assoc Physicians India ; 70(4): 11-12, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35443405

RESUMO

Hypertension is one of the leading causes of the global burden of disease. Screening for microalbuminuria is a sensitive, reliable and accessible test for renal disease and CV morbidity or mortality in hypertension. Reducing SBP but not DBP leads to a decrease in microalbuminuria. Therefore this study is intended to study the association of blood lipid level and urine microalbumin in hypertensive individuals in patients examined in Mandya Institute of Medical Science. Material and Objectives: To study the correlation of microalbuminuria and lipid profile in hypertensive patients. The study is a Descriptive cross-sectional study over a period of one year ( JUNE 2020- JUNE 2021). A minimum of 300 hypertensive patients admitted to the hospital or attending outpatient department with documented SBP ≥ 140mmHg and DBP ≥ 90 mmHg in age less than 65 years as per JNC 8 GUIDELINES were recruited into the study. History of treatment for hypertension were also included. Blood pressure was recorded with the patient well rested for ten minutes before recording, seated and an average of two readings on each of the two hospital visits. Lipid profile, blood sugar, urea and serum creatinine, urine examination and microalbuminuria by spot urine microalbumin creatinine ratio (MCR) was done for all patients. Observation: The prevalence of microalbuminuria was 51% in hypertensive individuals. TC, TG, HDL and Body Mass Index (BMI) were significantly higher in hypertensives with microalbuminuria than with normo albuminuria. There was a significant correlation of dyslipidemia and microalbuminuria in association with hypertension (p <0.05). There was higher prevalence of hypertension in male compared to female but did not have statistical significance (p >0.05). There was significantly higher age in the microalbuminuria group than with normoalbuminuric group of individuals (p <0.001). The duration of hypertension was in significant correlation with the occurrence of microalbuminuria in hypertensive individuals (p< 0.05). Conclusion: Authors conclude by saying that MA in hypertensive subjects may prove to be a valuable marker in the evaluation of target organ damage and control of risk factors amenable to prevention (regular treatment of HT, weight control, normal lipid levels) may have a favorable effect in preventing, delaying and lessening prevalence of MA. Early screening of hypertensive patients for MA and prompt treatment of positive cases may help reduce the burden of chronic kidney disease and cardiovascular disease in the community.


Assuntos
Hipertensão , Insuficiência Renal Crônica , Idoso , Albuminúria/epidemiologia , Albuminúria/etiologia , Estudos Transversais , Feminino , Humanos , Hipertensão/complicações , Lipídeos , Masculino , Insuficiência Renal Crônica/complicações
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