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1.
Blood Cells Mol Dis ; 105: 102821, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38218172

RESUMO

Dyslipidemia is frequently observed in polycystic ovarian syndrome (PCOS). Changes in plasma lipid levels potentially alter erythrocyte membrane lipid composition due to lack of inbuilt lipid synthesis machinery. Therefore, development of morphologically altered erythrocytes in PCOS patients with dyslipidemia is expected. However, this has not been established so far. So, we took this opportunity to explore the morphological alterations among dyslipidemic PCO women. We recruited thirty-five dyslipidemic PCOS women (satisfying Rotterdam criteria, without medication) and twenty-five age-matched healthy controls. Scanning electron microscopy revealed a significant increase in the number of stomatocytes, acanthocytes, and echinocytes in the PCO group. PCO group showed a considerable decrease in plasma antioxidant levels. Elevated lipid peroxidation, protein carbonylation, and decreased free thiol group in erythrocyte membrane in PCOS suggest oxidative degradation of the erythrocyte membrane. Elevated intracellular ROS levels, increased methemoglobin formation, and a decrease in NADPH methemoglobin reductase in PCOS also indicate altered physicochemical property of hemoglobin due to oxidative overload. Additionally, these patients exhibit a rise in erythrocyte membrane cholesterol and triglyceride, which promotes the membrane to become less fluidic and less fragile. Thus, these results corroborate a potential role in altering erythrocyte morphology among dyslipidemic PCO women.


Assuntos
Dislipidemias , Síndrome do Ovário Policístico , Humanos , Feminino , Triglicerídeos , Antioxidantes , Eritrócitos , Dislipidemias/complicações
2.
Biomacromolecules ; 23(6): 2428-2440, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35512287

RESUMO

The elevation of the chemotherapeutic efficacy and attenuation of its side effects on healthy cells and tissues become one of the prime targets for the treatment of cancer. Toward this direction, a sequential receptor and mitochondria dual-targeting strategy was implemented in the DX TP PG BN 19F theranostic polymer that was anchored with the chemotherapeutic agent doxorubicin, receptor-targeting biotin, and mitochondria-targeting triphenylphosphonium cations. The polymer was flourished with a unique 19F magnetic resonance imaging (MRI) tracer that exhibited high segmental mobility and eventually led to prolonged T2 relaxation time. Furthermore, for the sake of amphiphilicity, the DX TP PG BN 19F polymer spontaneously aggregated into nano-sphere with positive zeta potential, where the MRI tracer and biotin embedded at the exterior and displayed site-specific targeting and remarkable 19F MRI capability simultaneously. The mitochondria-targeting competency of the DX TP PG BN 19F theranostic polymer was investigated by comparing the non-mitochondrial-targeting DX PG BN 19F polymer using fluorescence microscopic cell imaging in human cervical, HeLa, and breast MCF-7 carcinoma cell lines. Moreover, cytotoxicity experiments of the aforementioned theranostic polymers clarified the enhancement of the chemotherapeutic efficacy of DX TP PG BN 19F theranostic polymers through effective and precise mitochondrial doxorubicin delivery that forced to follow the apoptotic path.


Assuntos
Fluorocarbonos , Polímeros , Biotina , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Humanos , Imageamento por Ressonância Magnética/métodos , Mitocôndrias , Nanomedicina Teranóstica/métodos
3.
Biomacromolecules ; 23(8): 3198-3212, 2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35767830

RESUMO

The sequential cancer cell receptor and mitochondria dual-targeting single delivery agent deliver chemotherapeutic drug effectively and precisely at the targeted site has become a promising strategy to enhance the drug efficacy and suppressions of cancer cell drug resistance prominence. Herein, required specialty molecules like a chemotherapeutic drug [camptothecin (CPT)], mitochondriotropic segment (triphenyl phosphonium cation) receptor targeting ligand (biotin), and magnetic resonance imaging (MRI)-contrast agent (iron-complex) were tethered to the polyprodrug, CP TP PG BN Fe, using the ring-opening metathesis polymerization technique for potential chemotherapy and simultaneous MRI-based diagnosis. This amphiphilic polyprodrug spontaneously aggregated into nanospheres and exhibited remarkable T1-weighted MRI proficiency. Detail in vitro cellular studies revealed unambiguous mitochondrial delivery of CPT, which eventually enhanced the chemotherapeutic efficacy of CP TP PG BN Fe. Therefore, MRI-tracking, receptor-mitochondria dual targeting, theranostic polyprodrug, and CP TP PG BN Fe opened the way for effective and precise chemotherapy, which would have the attractive potential for diagnosis and decisive dose determination in clinical implications.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Antineoplásicos/uso terapêutico , Camptotecina/farmacologia , Meios de Contraste/farmacologia , Meios de Contraste/uso terapêutico , Humanos , Ferro , Imageamento por Ressonância Magnética/métodos , Mitocôndrias/patologia , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Medicina de Precisão , Nanomedicina Teranóstica/métodos
4.
Phys Chem Chem Phys ; 19(26): 17360-17365, 2017 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-28650042

RESUMO

Understanding the changes in the macro-structure of amphiphilic pH-responsive polymers remains a relevant issue due to their potential use as drug delivery carriers. Since some of the amphiphilic polymers are known to exchange hydrogen ions with an aqueous solvent, we monitor the effective change of the surface to volume ratio of such polymer aggregates using solution-state nuclear magnetic resonance (NMR) spectroscopy. The surface to volume ratio with the help of UV-visible spectroscopy is shown to yield the average diameter of the polymer aggregates. We show that the proposed method not only satisfactorily corroborates the existing notions of how the aggregation of these polymers takes place as a function of pH, but also provides a quantitative estimate of the size of the aggregates.

5.
Phys Chem Chem Phys ; 17(48): 32384-9, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26584546

RESUMO

Recently, a sequence with a set of non-equidistant π pulses, often referred to as Uhrig's Dynamic Decoupling (UDD) sequence has been proposed which is shown to be more efficient in suppressing the time dependent systematic sources of dephasing originating from a bosonic bath. This work aims to investigate the potential of such non-equidistant sequences for more accurate measurement of the transverse relaxation time (T2) in liquid state NMR. We have shown experimentally that the dynamic decoupling schemes can estimate T2 more accurately than the equidistant pulse sequence by suppressing the dephasing effects of the field noise in the solution state.

6.
Asian Pac J Cancer Prev ; 24(7): 2543-2550, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37505789

RESUMO

BACKGROUND: To evaluate dosimetry between CT based radiation planning and PET-CT based radiation planning. MATERIAL & METHODS: Histologically proven 40 cases of locally advanced non-small cell carcinoma of lung were accrued for the prospective study. Contrast enhanced planning CT images and PET images were acquired. Target volume delineation, organs of interest & radiation planning were performed in Eclipse V 14.5 followed by dosimetric comparison among GTV, PTV and OARs. A p-value of <0.05 was considered significant. RESULTS: The mean of GTV were 141.18 ± 119.76 cc in CT and 115.54 ± 91.02 cc in PET-CT based and the difference was statistically significant (p=0.03). The mean of CTV were 313.91 ± 180.87 cc in CT and 260.81 ± 148.83 cc in PET-CT based and the difference was statistically significant (p=0.03). The contralateral lung mean dose was statistically very significant (p<0.01) among both the 3D-CRT plans which were 8.49 Gy in CECT based planning and 9.53 Gy in PET CT based planning. The heart mean dose was also statistically significant (p=0.03) among the plans which were 17.90 Gy in CECT based planning and 17.06 Gy in PET CT based planning. Mann-Whitney U test showed the CT based PTV D90 was 58.20 Gy vs 57.58 Gy in PET CT based planning (p=0.02). PTV V95 were also comparable in both of the plans (p=0.02). CONCLUSIONS: GTV measured using PET-CT, may be greater or lesser than the CECT-based GTV. PET-CT-based contouring is more accurate for identifying tumour margins and new lymph node volumes.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Prospectivos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patologia , Elétrons , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Dosagem Radioterapêutica , Fluordesoxiglucose F18
7.
ACS Chem Biol ; 18(4): 969-981, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-36976909

RESUMO

Target class profiling (TCP) is a chemical biology approach to investigate understudied biological target classes. TCP is achieved by developing a generalizable assay platform and screening curated compound libraries to interrogate the chemical biological space of members of an enzyme family. In this work, we took a TCP approach to investigate inhibitory activity across a set of small-molecule methyltransferases (SMMTases), a subclass of methyltransferase enzymes, with the goal of creating a launchpad to explore this largely understudied target class. Using the representative enzymes nicotinamide N-methyltransferase (NNMT), phenylethanolamine N-methyltransferase (PNMT), histamine N-methyltransferase (HNMT), glycine N-methyltransferase (GNMT), catechol O-methyltransferase (COMT), and guanidinoacetate N-methyltransferase (GAMT), we optimized high-throughput screening (HTS)-amenable assays to screen 27,574 unique small molecules against all targets. From this data set, we identified a novel inhibitor which selectively inhibits the SMMTase HNMT and demonstrated how this platform approach can be leveraged for a targeted drug discovery campaign using the example of HNMT.


Assuntos
Histamina N-Metiltransferase , Metiltransferases , Metiltransferases/química , Ensaios de Triagem em Larga Escala , Descoberta de Drogas
8.
ACS Appl Bio Mater ; 5(3): 1284-1296, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-35189682

RESUMO

Magnetic resonance imaging-aided real-time diagnosis along with enhanced chemotherapeutic efficacy using a sequential receptor and mitochondria dual-targeting polymer theranostic has become a promising strategy for the effective and precise treatment of cancer. Toward the accomplishment of this goal, chlorambucil (chemotherapeutic agent), biotin (receptor targeting agent), a triphenylphosphonium segment (mitochondriotropic agent), and an iron rhodamine complex (integrated fluorescence-MR imaging agent) were tethered under a single polymer. Owing to the polymer's (RD CH PG BN TP Fe) amphiphilic character, it spontaneously self-assembled into nanospheres, which exhibited a remarkable effect on the relaxation of the water proton. Further, the qualitative estimation of the change in intensity for the water-proton signal reflected its potential as a T1 contrast theranostic polymer. The mitochondria targeting competency of positively charged nanospheres was displayed using fluorescence microscopy in human cervical, HeLa, and breast, MCF-7, carcinoma cell lines. Furthermore, cytotoxicity experiments demonstrated the enhanced anticancer efficacy in both cancer cell lines. Therefore, effective and precise chemotherapy through sequential receptor-mitochondria targeting and integrated fluorescence-MR imaging would have attractive potential for decisive dose-determination by constantly monitoring the subject area of interest.


Assuntos
Neoplasias , Polímeros , Corantes/metabolismo , Humanos , Ferro/metabolismo , Imageamento por Ressonância Magnética , Mitocôndrias/metabolismo , Neoplasias/diagnóstico por imagem , Polímeros/metabolismo , Prótons , Nanomedicina Teranóstica , Água/metabolismo
9.
Carbohydr Res ; 510: 108452, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34634552

RESUMO

A straightforward synthesis of (+)-trans-(4S,5R)- and (+)-cis-(4R,5R)-whisky lactones starting from d-(+)-mannitol has been reported here in fewer number of efficient steps compared to existing literature processes involving d-mannitol as the chiral pool starting material. Chiron approach directly translated chirality of d-mannitol to one of the two chiral centers in these target molecules. Toward this end, stereoisomerically pure trans- and cis-iodomethyl-γ-lactones were formed in the penultimate step. These two acted as versatile advanced common intermediates as they were also converted to the (+)-trans-(4S,5R)- and (+)-cis-(4R,5R)-cognac lactones, respectively. To the best of our knowledge, till date no synthesis of cognac lactones starting from d-mannitol has been reported. All these lactones are identified as the key aroma components of aged alcoholic beverages.


Assuntos
4-Butirolactona/química , Bebidas Alcoólicas/análise , Lactonas/síntese química , Manitol/química , 4-Butirolactona/análogos & derivados , Lactonas/química , Estrutura Molecular , Estereoisomerismo
10.
ACS Chem Neurosci ; 12(15): 2903-2916, 2021 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-34292711

RESUMO

Solvent dynamics strongly induce the fibrillation of an amyloidogenic system. Probing the solvation mechanism is crucial as it enables us to predict different proteins' functionalities, such as the aggregation propensity, structural flexibility, and toxicity. This work shows that a straightforward NMR method in conjunction with phenomenological models gives a global and qualitative picture of water dynamics at different concentrations and temperatures. Here, we study amyloid system Aß40 and its fragment AV20 (A21-V40) and G37L (mutation at Gly37 → Leu of AV20), having different aggregation and toxic properties. The independent validation of this method is elucidated using all-atom classical MD simulation. These two state-of-the-art techniques are pivotal in linking the effect of solvent environment in the near hydration-shell to their aggregation nature. The time-dependent modulation in solvent dynamics probed with the NMR solvent relaxation method can be further adopted to gain insight into amyloidogenesis and link with their toxicity profiles.


Assuntos
Agregados Proteicos , Água , Peptídeos beta-Amiloides , Simulação de Dinâmica Molecular , Solventes
11.
Carbohydr Res ; 487: 107892, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31901892

RESUMO

Chiron approach was used to acquire optically pure (R)- and (S)-1-(2,6-dimethylphenoxy)propan-2-ol, immediate precursors of (S)- and (R)-mexiletines, respectively. Two different routes were followed from a D-mannitol-derived optically pure common precursor to get the enantiomeric alcohols separately. Comparison of their specific rotation values with the corresponding literature values as well as exact mirror-image relationship between their CD curves proved their high enantiopurity. These alcohols were then transformed to the corresponding amine-drugs in an efficient one-step process instead of two steps described in the literature.


Assuntos
Manitol/química , Mexiletina/química , Estrutura Molecular , Estereoisomerismo
12.
ChemMedChem ; 15(3): 293-301, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31762186

RESUMO

The three GxxxG repeating motifs from the C-terminal region of ß-amyloid (Aß) peptide play a significant role in regulating the aggregation kinetics of the peptide. Mutation of these glycine residues to leucine greatly accelerates the fibrillation process but generates a varied toxicity profile. Using an array of biophysical techniques, we demonstrated the uniqueness of the composite glycine residues in these structural repeats. We used solvent relaxation NMR spectroscopy to investigate the role played by the surrounding water molecules in determining the corresponding aggregation pathway. Notably, the conformational changes induced by Gly33 and Gly37 mutations result in significantly decreased toxicity in a neuronal cell line. Our results indicate that G33 xxxG37 is the primary motif responsible for Aß neurotoxicity, hence providing a direct structure-function correlation. Targeting this motif, therefore, can be a promising strategy to prevent neuronal cell death associated with Alzheimer's and other related diseases, such as type II diabetes and Parkinson's.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Fragmentos de Peptídeos/metabolismo , Doença de Alzheimer/metabolismo , Motivos de Aminoácidos , Relação Dose-Resposta a Droga , Humanos , Cinética , Estrutura Molecular , Relação Estrutura-Atividade
13.
Carbohydr Res ; 473: 5-11, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30590155

RESUMO

A short, simple and convenient chiron approach to (3R,4S,5R)-(-)-3,5-dihydroxy-4-decanolide, a hitherto unknown diastereomer of the reported structure of a naturally occurring acetogenin, (+)-polyporolide has been accomplished starting from a commercially available, inexpensive chiral pool molecule D-(+)-mannitol in nine efficient steps. An advanced intermediate synthesized from D-(+)-mannitol in six steps toward this end was further employed successfully to access two different natural products bearing two contiguous stereogenic centers. As a result, first chiron approach to formal total synthesis of an amide alkaloid, (4R,5R,2E)-4,5-dihydroxy-1-(piperidin-1-yl)dec-2-en-1-one and total synthesis of a male sex pheromone in parasitic Hymenoptera, (4R,5R)-(-)-5-hydroxy-4-decanolide have also been achieved.


Assuntos
Acetogeninas/química , Alcaloides/química , Amidas/química , Manitol/química , Atrativos Sexuais/química , Animais , Himenópteros , Masculino , Estereoisomerismo
14.
J Phys Chem B ; 122(22): 6094-6100, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29750525

RESUMO

Thermoresponsive polymers exhibit coil-globule transition in aqueous solution where the polymer undergoes transition from the coil-like morphology to a globular form with the change of temperature. Such transitions also reflect changes in the solvent dynamics captured by various spectroscopic methods. In this work, we construct a phenomenological model to capture the dynamics of the NMR relaxation of water molecules of an aqueous solution of thermoresponsive polymers that are known to form hydrogen bonds with the solvent water molecules. The model relies on the behavior of the polymer-solvent hydrogen bonds and the sharing of rotational kinetic energy of water molecules in the vicinity of the polymer chain and the bulk. This is shown to provide a direct estimate of the fractional change of the polymer-water hydrogen bonds across lower critical solution temperature from NMR relaxation data of solvent water along with a reliable estimate of the transition temperature. In addition, it also provides a measure of the dispersion of the strengths of these hydrogen bonds. We exemplify the validity of this model by successfully fitting the experimental data to show that the extracted parameters provide significant insights into the role played by the hydrogen bonds in the process. The possible extension of this model to solvents that form no hydrogen bonds with the polymers is also discussed.

15.
ACS Biomater Sci Eng ; 4(5): 1738-1749, 2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-33445331

RESUMO

Theranostic-based nanomedicine plays a crucial role in the field of cancer therapy. This is due to having the capability to combine both therapy and diagnosis together in a single system. Herein a new class of metal-ligand-based nanocarrier in a norbornene backbone has been designed as a theranostic system. Fe3+-terpyridine complex (Fe-Tpy) has been used here as T1 contrast agent for high-resolution MR imaging, and hydrazone-linked doxorubicin is used for effective pH-responsive delivery. Polyethylene glycol functionalized with a folic acid (peg folate) motif is used to make the entire polymeric system dispersible in water for longer retention and site-specific therapy. All these specialty functional groups are anchored in a single system by using the ring-opening metathesis polymerization (ROMP) technique under the norbornene backbone. Relaxivity study and 1D image experiments have shown the utility of Fe-Tpy complex as an effective T1 contrast agent. In vitro studies are performed to confirm the promising potentiality of the nanocarrier as the efficient nanotheranostic system in prostate cancer.

16.
ACS Omega ; 2(6): 2848-2857, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30023678

RESUMO

A multifunctional stimuli-responsive nanotheranostic agent provides huge benefits in nanomedicine by combining both the diagnostic agent and the drug molecule in a single system. This nanosystem is capable of doing multiple tasks, for example, diagnosis, drug delivery, and monitoring the therapeutic response. Hence, theranostic agents are expected to play a significant role in personalized medicine. Herein, a new class of nanotheranostic agents, Pnr-Cbt-Cpt-Pg-Bn, is proposed for the effective delivery of camptothecin. This new class of polymer has been functionalized with a superparamagnetic norbornene cobalt unit for its use in magnetic resonance imaging (MRI). The NMR one-dimensional image confirms the MRI capability of this nanotheranostic agent. This is further modified with the poly(ethylene glycol)-biotin moiety for biocompatibility and site-specificity. The uniqueness of the design is confirmed by an in vitro study where a greater uptake of the nanotheranostic agent is observed when compared with free drugs. Hence, this new class of copolymer shows improved potential as nanotheranostic agents in drug delivery.

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