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1.
Chem Asian J ; : e202400818, 2024 Oct 04.
Article in English | MEDLINE | ID: mdl-39363755

ABSTRACT

In this work, we unveil a novel synthesis of bench stable Ni (II) complexes supported by tetradentate Schiff-base ligands and the complexes were devoid of any phosphine or phosphine-based ligand. These Ni-complexes were successfully applied for the dehydrogenation of secondary alcohols for ketone and ketazine syntheses. Secondary alcohols with different functional groups were well tolerated during catalytic cycle. Moreover, we successfully extended this protocol for the synthesis of biologically significant ketones and ketazines. On the basis of various control experiments, probable reaction pathway was proposed and an acceptorless alcohol dehydrogenation mechanism was suggested.

2.
BMC Geriatr ; 24(1): 727, 2024 Sep 02.
Article in English | MEDLINE | ID: mdl-39223513

ABSTRACT

BACKGROUND: During the COVID-19 pandemic, patients with Alzheimer's disease and related dementias (ADRD) were especially vulnerable, and modes of medical care delivery shifted rapidly. This study assessed the impact of the pandemic on care for people with ADRD, examining the use of primary, emergency, and long-term care, as well as deaths due to COVID and to other causes. METHODS: Among 4.2 million beneficiaries aged 66 and older with ADRD in traditional Medicare, monthly deaths and claims for routine care (doctors' office and telehealth visits), inpatient/emergency department (ED) visits, and long-term care facility use from March or June 2020 through December 2022 are compared to monthly rates predicted from January-December 2019 using OLS and logistic/negative binomial regression. Correlation analyses examine the association between excess deaths - due to COVID and non-COVID causes - and changes in care use in the beneficiary's state of residence. RESULTS: Increased telehealth visits more than offset reduced office visits, with primary care visits increasing overall (by 9 percent from June 2020 onward relative to the predicted rate from 2019, p < .001). Emergency/inpatient visits declined (by 9 percent, p < .001) and long-term care facility use declined, remaining 14% below the 2019 trend from June 2020 onward (p < .001). Both COVID and non-COVID deaths rose, with 231,000 excess deaths (16% above the prediction from 2019), over 80 percent of which were attributable to COVID. Excess deaths were higher among women, non-White patients, those in rural and isolated zip codes, and those with higher social deprivation index scores. States with the largest increases in primary care visits had the lowest excess deaths (correlation -0.49). CONCLUSIONS: Older adults with ADRD had substantial deaths above pre-pandemic projections during the COVID-19 pandemic, 80 percent of which were attributed to COVID-19. Routine care increased overall due to a dramatic increase in telehealth visits, but this was uneven across states, and mortality rates were significantly lower in states with higher than pre-pandemic visits.


Subject(s)
COVID-19 , Dementia , Telemedicine , Humans , COVID-19/mortality , COVID-19/epidemiology , Aged , United States/epidemiology , Female , Male , Telemedicine/trends , Dementia/epidemiology , Dementia/mortality , Dementia/therapy , Aged, 80 and over , Medicare/trends , Office Visits/trends , Office Visits/statistics & numerical data , Emergency Service, Hospital/trends , Emergency Service, Hospital/statistics & numerical data , Pandemics , Long-Term Care/trends , Long-Term Care/statistics & numerical data
3.
Adv Healthc Mater ; : e2401991, 2024 Sep 02.
Article in English | MEDLINE | ID: mdl-39221545

ABSTRACT

Neurodegenerative disorders (NDDs) are a class of debilitating diseases that progressively impair the protein structure and result in neurological dysfunction in the nervous system. Among these disorders, Alzheimer's disease (AD), prion diseases such as Creutzfeldt-Jakob disease (CJD), and Parkinson's disease (PD) are caused by protein misfolding and aggregation at the cellular level. In recent years, transition metal complexes have gained significant attention for their potential applications in diagnosing, imaging, and curing these NDDs. These complexes have intriguing possibilities as therapeutics due to their diverse ligand systems and chemical properties and can interact with biological systems with minimal detrimental effects. This review focuses on the recent progress in transition metal therapeutics as a new era of hope in the battle against AD, CJD, and PD by modulating protein aggregation in vitro and in vivo. It may shed revolutionary insights into unlocking new opportunities for researchers to develop metal-based drugs to combat NDDs.

4.
Small ; : e2406113, 2024 Sep 16.
Article in English | MEDLINE | ID: mdl-39279593

ABSTRACT

Fabrication of cost-effective and robust metal-based electrocatalysts for hydrogen evolution reactions (HER) across the entire pH range has garnered significant attention in harvesting renewable energy. Herein, the fabrication of 3D high-surface Ni Foam-Graphene-Carbon Nanotubes (NGC) decorated with phosphorous-inserted tin selenide (SnSe-P) showcases unprecedented HER activity with minimal overpotentials across all pH ranges (52 mV in acidic, 93 mV in basic, and 198 mV in neutral conditions@10 mA cm-2) and stability at 1 A cm-2 for 72 h. The as-designed catalyst shows a low overpotential of 122 mV@10 mA cm-2 in alkaline seawater, achieved through controlled electronic distribution on Sn site after incorporation of P in NGC-SnSe-P. A stable cell voltage of 1.56 V@10 mA cm⁻2 is achieved for prolonged time in 1 m KOH toward overall water electrolysis. Experimental and theoretical investigation reveals that the insertion of P in layered SnSe enables s orbitals of H* and p orbitals of Sn to interact, favoring the adsorption of the H* intermediate. A renewable approach is adopted by using silicon solar cells (η = 10.66%) to power up the electrolyzer, yielding a solar-to-hydrogen (STH) conversion efficiency of 7.70% in 1 m KOH and 5.65% in alkaline seawater, aiming toward green hydrogen production.

5.
Chemistry ; : e202403256, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39301674

ABSTRACT

A newly developed dual-functional fluorescence sensing probe (phenylhydrazinyl pyridine) Schiff base (SB) has been designed with good selectivity for distinguishing Mg2+ and Al3+ metal ions in different solvent solutions. SB exhibits quick and visual turn-on fluorescence enhancement in response to Mg2+ and Al3+ detection. The addition of Mg2+ in ACN-HEPES buffer (1:1, v/v, pH 7.2) at (λmax = 390 nm) and Al3+ in MeOH-HEPES buffer (1:1, v/v, pH 7.2) at  (λmax = 360 nm) resulted in significant enhancement of fluorescence, up to 7 - 9 times. These low detection limits of 7.1 × 10-6 M (7.1 µM) and 5.15 × 10-7 M (0.51 µM) for Mg2+ and Al3+, respectively, have been achieved by this solvent-controlled platform. Due to the sensing potential towards Mg2+, the probe was utilized as an imaging material for breast cancer cells. 1H-NMR studies were utilized to explore SB's sensing mechanism through turn-on fluorescence. Density functional theory (DFT) calculations were utilized to validate optimized SB and its intricate geometries, which govern the sensing mechanism in the solvent environment. Such a probe has extensive potential applications in bioimaging and the assessment of the quality of wastewater.

6.
Org Biomol Chem ; 2024 Sep 25.
Article in English | MEDLINE | ID: mdl-39318345

ABSTRACT

Herein, we present the first efficient and sustainable multicomponent synthesis (MCS) of 2-pyrazolines using acceptorless dehydrogenation of benzyl alcohols catalysed by nickel(II) catalysts. Two air-stable phosphine free nickel(II) complexes anchored by NNN-type pincer ligands were synthesized and efficiently used in the MCS of 40 distinct pyrazoline derivatives.

7.
J Assoc Physicians India ; 72(9): 58-63, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39291518

ABSTRACT

INTRODUCTION: Serum sodium levels <135 mmol/L are known as hyponatremia. The syndrome of inappropriate antidiuresis (SIAD), which is described by a drop in the effective arterial blood volume (EABV), is the most common cause of hyponatremia. This study was carried out to categorize hyponatremia based on volume status and on parameters like fractional excretion of uric acid (FE-UA), fractional excretion of sodium (FE-Na), urine uric acid (U-UA), and serum uric acid (SR-UA) values. MATERIALS AND METHODS: Sixty-one patients admitted to the Department of Medicine at Rajendra Institute of Medical Sciences (RIMS), Ranchi, with hyponatremia were included in the study by applying random sampling. Routine urine and blood samples were collected for biochemical tests. Institutional ethical clearance was obtained for this study. Data were analyzed using Statistical Package for the Social Sciences (SPSS) (version 21). Frequency, central tendency, receiver operating characteristic (ROC), and nonparametric Mann-Whitney U test analysis tools were utilized for analysis. RESULTS: Syndrome of inappropriate antidiuretic hormone secretion (SIADH) was found in nearly 50.82% of hyponatremic patients. Approximately, 70% of non-SIADH patients were hypovolemic. When compared to the non-SIADH group, patients in the SIADH group had significantly higher systolic blood pressure (SBP) and diastolic blood pressure (DBP), lower pulse rates, and lower urine creatinine levels and urine creatinine to serum creatinine ratio. The non-SIADH group had significantly higher SR-UA levels (p < 0.0001), but the SIADH group had significantly higher U-UA levels and significantly lower SR-UA levels. Among the studied parameters, FE-UA was the most accurate in diagnosing SIADH. FE-UA (>12%) is a better diagnostic marker for distinguishing SIADH patients from non-SIADH patients. CONCLUSION: FE-uric acid was found to be the most superior in diagnosing SIADH, followed by FE-Na.


Subject(s)
Hyponatremia , Inappropriate ADH Syndrome , Sodium , Uric Acid , Humans , Hyponatremia/urine , Hyponatremia/diagnosis , Hyponatremia/etiology , Uric Acid/urine , Uric Acid/blood , Female , Male , Inappropriate ADH Syndrome/diagnosis , Inappropriate ADH Syndrome/urine , Middle Aged , Sodium/urine , Sodium/blood , Adult , Aged , Electrolytes/urine , Electrolytes/blood
8.
J Med Chem ; 67(16): 14184-14199, 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39102502

ABSTRACT

Galectin-3 (Gal-3) is a carbohydrate binding protein that has been implicated in the development and progression of fibrotic diseases. Proof-of-principal animal models have demonstrated that inhibition of Gal-3 is a potentially viable pathway for the treatment of fibrosis─with small molecule Gal-3 inhibitors advanced into clinical trials. We hereby report the discovery of novel galactose-based monosaccharide Gal-3 inhibitors comprising 2-methyl-4-phenyl-2,4-dihydro-3H-1,2,4-triazole-3-thione (compound 20) and 4-phenyl-4H-1,2,4-triazole (compound 15). Notably, hindered rotation caused by steric interaction between the 3-thione and ortho-trifluoromethyl group of compounds 20, 21 induced formation of thermodynamically stable atropisomers. Distinct X-ray cocrystal structures of 20 and 21 were obtained, which clearly demonstrated that the configuration of 21 proscribes a key halogen bonding σ-hole interaction of 3-chloro with carbonyl oxygen of Gly182, thereby leading to significant loss in potency. Ultimately, 20 and 15 were evaluated in mouse pharmacokinetic studies, and both compounds exhibited oral exposures suitable for further in vivo assessment.


Subject(s)
Galactose , Galectin 3 , Triazoles , Triazoles/chemistry , Triazoles/pharmacology , Triazoles/chemical synthesis , Triazoles/pharmacokinetics , Galactose/chemistry , Galactose/metabolism , Animals , Humans , Galectin 3/antagonists & inhibitors , Galectin 3/metabolism , Mice , Structure-Activity Relationship , Crystallography, X-Ray , Thiones/chemistry , Thiones/pharmacology , Thiones/chemical synthesis , Thiones/pharmacokinetics , Blood Proteins/metabolism , Galectins/antagonists & inhibitors , Galectins/metabolism , Models, Molecular
9.
Cureus ; 16(7): e64261, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39130827

ABSTRACT

Scrub typhus is a zoonotic feverish condition that can range from mild to severe, potentially life-threatening symptoms. Common signs include fever, headache, muscle pain, and a skin rash. Although rare, splenic infarction is a known complication of scrub typhus, with only a limited number of cases documented in medical literature. The case of a 68-year-old male with fever and abdominal discomfort, ultimately diagnosed with both scrub typhus and splenic infarct, illustrates the importance of recognizing splenic infarction as a potential complication of scrub typhus, particularly in areas where the disease is prevalent. The patient was promptly diagnosed and managed with a favorable outcome.

10.
Chempluschem ; : e202400219, 2024 Aug 10.
Article in English | MEDLINE | ID: mdl-39126688

ABSTRACT

Copper catalyzed intramolecular annulation of 2-((2benzylidene-1-phenylhydrazineyl)methyl)pyridine derivatives was described. It was found that Cu(II) is reduced under the reaction condition to Cu(I). Synthesized 1, 2-dihydro [1,2,4] triazinium salt showed fluorescence activity in solid state. On treating with base, an instant increase in fluorescence was observed. A detailed physicochemical assessment underscored the robust DNA-binding prowess of the [1,2,4] triazinium cationic species (C1-C3) via intercalative mechanisms. Notably, binding assays with BSA accentuated the heightened nucleic acid affinity of these cationic species.

11.
Nanoscale ; 16(30): 14350-14357, 2024 Aug 07.
Article in English | MEDLINE | ID: mdl-39018112

ABSTRACT

Liquid electronics have potential applications in soft robotics, printed electronics, and healable electronics. The intrinsic shortcomings of solid-state electronics can be offset by liquid conductors. Alloys of gallium have emerged as transformative materials for liquid electronics owing to their intrinsic fluidity, conductivity, and low toxicity. However, sculpting liquid metal or its composites into a 3D architecture is a challenging task. To tackle this issue, herein, we explored the interfacial chemistry of metal ions and tannic acid (TA) complexation at a liquid-liquid interface. First, we established that an MIII-TA network at the liquid-liquid interface could structure liquid in liquid by jamming the interfacial film. The surface coverage of the droplet largely depends on the concentration of metal ions, oxidation state of metal ions and pH of the surrounding environment. Further extending the approach, we demonstrated that TA-functionalized gallium nanoparticles (Ga NPs) can also sculpt liquid droplets in the presence of transition metal ions. Finally, a mold-based free-standing 3D architecture is obtained using the interfacial reaction and interfacial crowding of a metal-phenolate network. Conductivity measurement reveals that these liquid constructs can be used for low-voltage electronic applications, thus opening the door for liquid electronics.

12.
Dalton Trans ; 53(28): 11995-12006, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-38963284

ABSTRACT

The spontaneous aggregation of infectious or misfolded forms of prion protein is known to be responsible for neurotoxicity in brain cells, which ultimately leads to the progression of prion disorders. Bovine spongiform encephalopathy (BSE) in animals and Creutzfeldt-Jakob disease (CJD) in humans are glaring examples in this regard. Square-planar complexes with labile ligands and indole-based compounds are found to be efficiently inhibitory against protein aggregation. Herein, we report the synthesis of an indole-based cyclometallated palladium complex. The ligand and complex were characterized by various spectroscopic techniques such as UV-visible, NMR, IR, and HRMS. The molecular structure of the complex was confirmed by single-crystal X-ray crystallography. The interaction of the complex with PrP106-126 was studied using UV-visible spectroscopy, CD spectroscopy, MALDI-TOF MS, and molecular docking. The inhibition effects of the complex on the PrP106-126 aggregation, fibrillization and amyloid formation phenomena were analysed through the ThT assay, CD, TEM and AFM. The effect of the complex on the aggregation process of PrP106-126 was determined kinetically through the ThT assay. The complex presented high binding affinity with the peptide and influenced the peptide's conformation and aggregation in different modes of binding. Furthermore, the MTT assay on neuronal HT-22 cells showed considerable protective properties of the complex against PrP106-126-mediated cytotoxicity. These findings suggest that the compound influences peptide aggregation in different ways, and the anti-aggregation action is primarily associated with the metal's physicochemical properties and the reactivity rather than the ligand. As a result, we propose that this compound be investigated as a potential therapeutic molecule in metallopharmaceutical research to treat prion disease (PD).


Subject(s)
Coordination Complexes , Indoles , Palladium , Protein Aggregates , Palladium/chemistry , Palladium/pharmacology , Humans , Indoles/chemistry , Indoles/pharmacology , Protein Aggregates/drug effects , Coordination Complexes/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/chemical synthesis , Molecular Docking Simulation , Peptide Fragments/chemistry , Peptide Fragments/pharmacology , Peptide Fragments/metabolism , Prion Proteins/chemistry , Prion Proteins/metabolism , Prion Proteins/antagonists & inhibitors , Prions
13.
Dalton Trans ; 53(20): 8740-8749, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38712566

ABSTRACT

This work describes a new well-defined, air-stable, phosphine free palladium(II) [Pd(L)Cl] (1) catalyst. This catalyst was utilized for N-alkylation of amines and indole synthesis where H2O was found to be the by-product. A broad range of aromatic amines were alkylated using this homogeneous catalyst with a catalyst loading of 0.1 mol%. Greener aromatic and aliphatic primary alcohols were utilized and a hydrogen auto-transfer strategy via a metal-ligand cooperative approach was investigated. The precursor of the antihistamine-containing drug molecule tripelennamine was synthesized on a gram scale for large-scale applicability of the current synthetic methodology. A number of control experiments were performed to investigate the possible reaction pathway and the outcomes of these experiments indicated the azo-chromophore as a hydrogen reservoir during the catalytic cycle.

14.
ACS Appl Mater Interfaces ; 16(20): 26899-26914, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38741334

ABSTRACT

The extreme sensitivity of 2D-layered materials to environmental adsorbates, which is typically seen as a challenge, is harnessed in this study to fine-tune the material properties. This work investigates the impact of environmental adsorbates on electrical properties by studying metal-semiconductor-metal (MSM) devices fabricated on CVD-synthesized SnSe flakes. The freshly prepared devices exhibit positive photoconductivity (PPC), whereas they gradually develop negative photoconductivity (NPC) after being exposed to an ambient environment for ∼1 day. While the photodetectors based on positive photoconductivity exhibit a responsivity and detectivity of 6.1 A/W and 5.06 × 108 Jones, the same for the negative photoconductivity-based photodetector reaches up to 36.3 A/W and 1.49 × 109 Jones, respectively. In addition, the noise-equivalent power of the NPC photodetector decreases by 300 times as compared to the PPC device, which implies a prominent detection capability of the NPC device against weak photo signals. To substantiate the hypothesis that negative photoconductivity stems from the photodesorption of water and oxygen molecules on the dangling bonds of SnSe flakes, the flakes are etched along the most active planes (010) with a focused laser beam in an inert environment, which enhances responsivity by 43%, supporting negative photoconductivity linked to photodesorption. Furthermore, the humidity-dependent dark current variation of the NPC photodetectors is used to design a humidity sensor for human respiration monitoring with faster response and recovery times of 0.72 and 0.68 s, respectively. These findings open up the possibility of tuning the photoelectrical response of layered materials in a facile manner to develop future sensors and optoelectronic multifunctional devices.

15.
Toxicol Res (Camb) ; 13(2): tfae058, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38617714

ABSTRACT

The present study aimed to elucidate the short term biodistribution of nano sized graphene oxide (GO) along with the toxicological assessment under in-vivo condition with an intent to analyse the toxic effects of sudden accidental exposure of GO The synthesised GO was characterized using UV-Visible spectroscopy, XRD, FTIR, Raman spectroscopy, TGA and DLS. The morphological imaging was performed using SEM, TEM and AFM. With a lateral size of less than 300 nm, these nanoparticles exhibit significant organ barrier permeability of up to 20%. Upon acute exposure to 10 mg/kg dose of ICG-tagged GO nanoflakes through intravenous route, various organs such as kidney, spleen and liver were observed, and the nanoparticles predominantly accumulated in the liver upon 24 h of exposure. Upon confirming the accumulation of these particles in liver through IVIS imaging, our next attempt was to analyse various biochemical and serum parameters. An elevation in various serum parameters such as ALT, AST, Creatinine and Bilirubin was observed. Similarly, in the case of biochemical parameters tested in liver homogenates, an increase in NO, Catalase, GSH, SOD, ROS, LPO, GR, GPx, and GST was observed. This study highlights the potential toxicological risk associated with GO exposure which must be taken into account for any risk analysis associated with GO based consumer products and the occupational hazards.

16.
Brain Spine ; 4: 102797, 2024.
Article in English | MEDLINE | ID: mdl-38601773

ABSTRACT

Introduction: Leptomeningeal melanocytomas are rare tumours originating from neural crest derived melanocytes. They are usually solitary and presentation with multifocal meningeal melanocytoma is very rare and indicative of potentially more aggressive behaviour. This case report and scoping review sought to evaluate the presentation, and key radiological features that can help differentiate multifocal meningeal melanocytoma from other differentials and provide a discussion of the key management and prognostic points once these tumours are diagnosed. Case presentation: A 26 year old male presented with neck pain radiating to both shoulders and subjective weakness in left shoulder movement. MRI demonstrated a large enhancing C2-C3 intradural-extramedullary lesion with further lesions at the T7/T8 level, left cerebellopontine angle and midline suprachiasmatic region. Whilst the imaging appearances were initially thought be indicative of a phacomatosis such as NF2-related schwannomatosis, surgical excision of the cervical tumour confirmed a melanocytic tumour of leptomeningeal origin, consistent with multifocal meningeal melanocytoma. Patient made a good post-operative recovery and remains under half yearly radiological surveillance, with repeat MRI 6 months after surgery demonstrating subtle growth of the untreated intracranial and spinal lesions. Literature review and conclusions: This is the first description, to our knowledge, of a multifocal meningeal melanocytoma associated with both cerebellopontine angle and suprasellar lesions. This case and included scoping review highlight the need to consider this rare diagnosis whenever multifocal craniospinal lesions are encountered, and the need to consider aggressive management through surgical resection and adjuvant craniospinal radiotherapy once these tumours are diagnosed.

17.
Bioorg Med Chem ; 101: 117638, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38394996

ABSTRACT

As a result of our continued efforts to pursue Gal-3 inhibitors that could be used to fully evaluate the potential of Gal-3 as a therapeutic target, two novel series of benzothiazole derived monosaccharides as potent (against both human and mouse Gal-3) and orally bioavailable Gal-3 inhibitors, represented by 4 and 5, respectively, were identified. These discoveries were made based on proposals that the benzothiazole sulfur atom could interact with the carbonyl oxygen of G182/G196 in h/mGal-3, and that the anomeric triazole moiety could be modified into an N-methyl carboxamide functionality. The interaction between the benzothiazole sulfur and the carbonyl oxygen of G196 in mGal-3 was confirmed by an X-ray co-crystal structure of early lead 9, providing a rare example of using a S···O binding interaction for drug design. It was found that for both the series, methylation of 3-OH in the monosaccharides caused no loss in h & mGal-3 potencies but significantly improved permeability of the molecules.


Subject(s)
Galectin 3 , Monosaccharides , Animals , Humans , Mice , Benzothiazoles/chemistry , Benzothiazoles/pharmacology , Drug Design , Galectin 3/antagonists & inhibitors , Galectins/antagonists & inhibitors , Monosaccharides/chemistry , Monosaccharides/pharmacology , Oxygen , Sulfur
18.
Haematologica ; 109(4): 1082-1094, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-37941406

ABSTRACT

Oral azacitidine (oral-Aza) treatment results in longer median overall survival (OS) (24.7 vs. 14.8 months in placebo) in patients with acute myeloid leukemia (AML) in remission after intensive chemotherapy. The dosing schedule of oral-Aza (14 days/28-day cycle) allows for low exposure of Aza for an extended duration thereby facilitating a sustained therapeutic effect. However, the underlying mechanisms supporting the clinical impact of oral-Aza in maintenance therapy remain to be fully understood. In this preclinical work, we explore the mechanistic basis of oral-Aza/extended exposure to Aza through in vitro and in vivo modeling. In cell lines, extended exposure to Aza results in sustained DNMT1 loss, leading to durable hypomethylation, and gene expression changes. In mouse models, extended exposure to Aza, preferentially targets immature leukemic cells. In leukemic stem cell (LSC) models, the extended dose of Aza induces differentiation and depletes CD34+CD38- LSC. Mechanistically, LSC differentiation is driven in part by increased myeloperoxidase (MPO) expression. Inhibition of MPO activity either by using an MPO-specific inhibitor or blocking oxidative stress, a known mechanism of MPO, partly reverses the differentiation of LSC. Overall, our preclinical work reveals novel mechanistic insights into oral-Aza and its ability to target LSC.


Subject(s)
Azacitidine , Leukemia, Myeloid, Acute , Animals , Mice , Humans , Azacitidine/pharmacology , Azacitidine/therapeutic use , Antigens, CD34/metabolism , Leukemia, Myeloid, Acute/genetics , Peroxidase , Stem Cells/metabolism
19.
Dalton Trans ; 53(3): 986-995, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38088032

ABSTRACT

Copper complexes [Cu(L1H)ClO4] (1) and [Cu(L2)NO3] (2), which are relevant to the metal site of the galactose oxidase enzyme, were synthesized and characterized by different spectroscopic methods. L1H2 and L2H2 [where L1H2 stands for 2,2'-((1E,1'E)(2,2'-(pyridine-2,6-diyl)bis(2-phenylhydrazin-2-yl-1-ylidene))bis(methanylylidene))diphenol and L2H2 stands for 6,6'-((1E,1'E)-(2,2'-(pyridine-2,6-diyl)bis(2-phenylhydrazin-2-yl-1-ylidene))bis(methanylylidene))bis(2,4-di-tert-butylphenol), H stands for dissociable proton] are pentadentate ligands. These ligands provide pyridyl N, two imine N, and two non-innocent phenoxyl and phenolato O donors, forming complex 1 as a non-radical complex, while complex 2 is a phenoxyl radical complex. The molecular structures of complexes 1 and 2 were authenticated by X-ray crystallography. Benzyl alcohol oxidation was investigated, and the conversion of 9,10-dihydroanthracene to anthracene was examined to scrutinize the H-atom abstraction reaction. Nuclease activity with complexes 1 and 2 was investigated by self-activated plasmid DNA (pBR322) cleavage. Non-innocent properties of the ligand-containing phenolato function were investigated by DFT calculations.


Subject(s)
Copper , Hydrogen , Phenols , Copper/chemistry , Galactose Oxidase/chemistry , DNA Cleavage , Metals , Pyridines , Ligands , Crystallography, X-Ray
20.
Inorg Chem ; 63(1): 714-729, 2024 Jan 08.
Article in English | MEDLINE | ID: mdl-38150362

ABSTRACT

Ligands derived from 2-(1-phenylhydrazinyl)pyridine and salicylaldehyde (HL1), 3-methoxysalicylaldehyde (HL2), 5-bromosalicylaldehyde (HL3), and 3,5-di-tert-butylsalicylaldehyde (HL4) react with [VIVO(acac)2] in MeOH followed by aerial oxidation to give [VVO2(L1)] (1), [VVO2(L2)] (2), [VVO2(L3)] (3), and [VVO2(L4)] (4). Complex [VIVO(acac)(L1)] (5) is also isolable from [VIVO(acac)2] and HL1 in dry MeOH. Structures of all complexes were confirmed by single-crystal X-ray and spectroscopic studies. They efficiently catalyze benzyl alcohol and its derivatives' oxidation in the presence of H2O2 to their corresponding aldehydes. Under optimized reaction conditions using 1 as a catalyst precursor, conversion of benzyl alcohol follows the order: 4 (93%) > 2 (90%) > 1 (86%) > 3 (84%) ≈ 5 (84%). These complexes were also evaluated for antifungal and antiproliferative activities. Complex 3 with MIC50 = 16 µg/mL, 4 with MIC50 = 12 µg/mL, and 5 with MIC50 = 16 µg/mL are efficient toward planktonic cells of Candida albicans and Candida tropicalis. On Michigan cancer foundation-7 (MCF-7) cells, they show comparable cytotoxic effects and exhibit IC50 in the 27.3-33.5 µg/mL range, and among these, 4 exhibits the highest cytotoxicity. A similar study on human embryonic kidney cells (HEK293) confirms their less toxicity at lower concentrations (4 to 16 µg/mL) compared to MCF-7.


Subject(s)
Antifungal Agents , Vanadium , Humans , Vanadium/chemistry , Antifungal Agents/pharmacology , Hydrogen Peroxide/chemistry , HEK293 Cells , Benzyl Alcohols , Ligands
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