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1.
Mymensingh Med J ; 30(2): 420-425, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33830123

RESUMEN

Different types of solitary brain lesions and also tumefactive demyelinating lesions exhibit many features on CT and MRI that are characteristics of malignancy and surgical biopsy is often performed in suspected tumour. Proton MR Spectroscopy has been used to differentiate different type of these solitary brain lesions. Our purpose is to determine whether MR spectroscopy is able to improve preoperative diagnostic accuracy in case of intracranial solitary tumors. This cross sectional study was carried out among 44 patients who were referred to Radiology and Imaging Department by Neurosurgery and Neuro-medicine department of BSMMU, Dhaka, Bangladesh as MRI suspected glioma for MRS scan during the period of 24 months. MRS was performed in 44 patients with suspected glioma. Metabolic ratio of choline: Cr, NAA: Cr, Lactate: Cr was calculated in short and intermediated echo times (TES). Tumors were subdivided into neoplasm and inflammatory mass. Neoplasm was again subdivided into glioblastoma multiforme and solitary metastasis. The patients were followed up and surgical resection biopsy reports were collected. MRS findings and histopathological findings were then correlated. In this study 68.18% of patients were diagnosed as Glioblastoma multiform by MRS and also in histopathology 18.18%. Patient was diagnosed as solitary metastasis in MRS and 20.45%. Patient was diagnosed as solitary metastasis by histopathology and 13.64%. Patient was diagnosed as abscess in MRS while in histopathology 11.37% patients were diagnosed as abscess.


Asunto(s)
Neoplasias Encefálicas , Glioma , Bangladesh , Encéfalo , Neoplasias Encefálicas/diagnóstico por imagen , Estudios Transversales , Humanos , Espectroscopía de Resonancia Magnética
2.
Adv Exp Med Biol ; 1310: 187-209, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33834438

RESUMEN

Given the merit of high-resolution cross-sectional imaging, magnetic resonance imaging (MRI) has been utilized in many preclinical and clinical research fields. In addition to T2-weighted imaging for assessing anatomic changes by disease and therapeutic agents, diffusion-weighted imaging, dynamic contrast-enhanced MRI, and MR spectroscopy can provide disease- and drug-specific functional information in both in vivo and ex vivo status. Another advantage of MRI is its ability to bridge the preclinical and clinical experiments as it allows similar study methods and environments between animals and humans. Therefore, MRI can be used as a useful tool for drug development. Investigators have discovered a variety of MRI biomarkers that can quantitatively measure the biological alteration led by disease and treatment. In this chapter, a number of commonly used preclinical MRI biomarkers for drug development will be introduced and discussed, particularly being focused on their value for translational research.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Imagen por Resonancia Magnética , Medios de Contraste , Desarrollo de Medicamentos , Humanos , Espectroscopía de Resonancia Magnética
3.
Adv Exp Med Biol ; 1280: 19-37, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33791972

RESUMEN

Nuclear magnetic resonance (NMR) spectroscopy is a major analytical method used in the growing field of metabolomics. Although NMR is relatively less sensitive than mass spectrometry, this analytical platform has numerous characteristics including its high reproducibility and quantitative abilities, its nonselective and noninvasive nature, and the ability to identify unknown metabolites in complex mixtures and trace the downstream products of isotope labeled substrates ex vivo, in vivo, or in vitro. Metabolomic analysis of highly complex biological mixtures has benefitted from the advances in both NMR data acquisition and analysis methods. Although metabolomics applications span a wide range of disciplines, a majority has focused on understanding, preventing, diagnosing, and managing human diseases. This chapter describes NMR-based methods relevant to the rapidly expanding metabolomics field.


Asunto(s)
Imagen por Resonancia Magnética , Metabolómica , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Reproducibilidad de los Resultados
4.
Adv Exp Med Biol ; 1280: 115-130, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33791978

RESUMEN

Metabolic rewiring/reprogramming is an essential hallmark of cancer. Alteration of metabolic phenotypes is occurred in cancer cells in response to a harsh condition to support cancer cell proliferation, survival, and metastasis. Stable isotope can be used as a tracer to investigate the redistribution of the carbons labeled in glucose in order to elucidate the detailed mechanisms of cellular rewiring and reprogramming in tumor microenvironment. Stable isotope-resolved metabolomics (SIRM) is an analytical method inferring metabolic networking by using advanced nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) to analyze the fate of a single atom from a stable isotope-enriched precursor to a product metabolite. This methodology has been demonstrated for a wide range of biological applications, including cancer metabolomic analysis. The basic principle and platforms of SIRM and its implication for cancer metabolism research will be addressed in this chapter.


Asunto(s)
Metabolómica , Neoplasias , Humanos , Marcaje Isotópico , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Neoplasias/genética , Microambiente Tumoral
5.
Adv Exp Med Biol ; 1280: 201-218, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33791984

RESUMEN

Nuclear magnetic resonance (NMR) spectroscopy offers reproducible quantitative analysis and structural identification of metabolites in various complex biological samples, such as biofluids (plasma, serum, and urine), cells, tissue extracts, and even intact organs. Therefore, NMR-based metabolomics, a mainstream metabolomic platform, has been extensively applied in many research fields, including pharmacology, toxicology, pathophysiology, nutritional intervention, disease diagnosis/prognosis, and microbiology. In particular, NMR-based metabolomics has been successfully used for cancer research to investigate cancer metabolism and identify biomarker and therapeutic targets. This chapter highlights the innovations and challenges of NMR-based metabolomics platform and its applications in cancer research.


Asunto(s)
Líquidos Corporales , Neoplasias , Biomarcadores , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Metabolómica
6.
Urologiia ; (1): 90-94, 2021 Mar.
Artículo en Ruso | MEDLINE | ID: mdl-33818942

RESUMEN

PURPOSE: In order to determine the role and significance of functional magnetic resonance urography (fMRU) in the diagnosis of ureteropelvic junction obstruction (UPJO), a comparative analysis of the results of fMRU and dynamic renal scintigraphy (DRS) was carried out. MATERIALS AND METHODS: From January 2017 to December 2019, fMRU and diuretic DRS were performed in 36 patients (mean age 89+/-63 months). Boys - 26 (72.2%), girls - 10 (27.8%). Left-sided hydronephrosis was detected in 23 (63.9%) children, right-sided in 12 (33.3%) patients, and bilateral lesions in 1 (2.8%) patient (2 renal units (RU)). Antenatal hydronephrosis was detected in 9 (25%) patients, and postnatally in 27 (75%) patients. According to ultrasound data, grade II hydronephrosis occurred in 11 (29.8%) RU, grade III - in 21 RU (56.7%), and grade IV - in 5 RU (13.5%) according to the SFU classification. A diuretic test was performed in 26 patients. RESULTS: Median and quartiles of differential renal function (DRF) according to fMRU data on the affected side were 37% [29; 43], and according to DRS - 46% [40;49]. When performing fMRU, a positive diuretic test was detected in 20 patients, 5 patients - negative and 1 patient - doubtful, and according to the DRS data, 12 patients had a positive test, 10 patients - negative and 4 patients - doubtful. Differences in DRF between fMRU and DRS varied between 0.7-33%. The average value of differences in DRF on the affected side was 11.3+/-8.5%. When comparing the results of DRF on the affected side, a moderate correlation was found on the Cheddock scale (r=0.59, p<0.05) between fMRU and DRS data. In comparison of the DRF using the Wilcoxon test, statistically significant differences were revealed (p<0,05). SUMMARY: Our experience demonstrates the high potential of fMRU in terms of replacing the classical methods of diagnosis of UPJO in children, taking into account the high correlation coefficients between the results of fMRU and DRS. Standardization of the fMRU protocol will increase the diagnostic relevance of information and in the future will make fMRU the only necessary study to determine management tactics for patients with UPJO.


Asunto(s)
Hidronefrosis , Obstrucción Ureteral , Niño , Femenino , Humanos , Hidronefrosis/diagnóstico por imagen , Lactante , Pelvis Renal/diagnóstico por imagen , Espectroscopía de Resonancia Magnética , Masculino , Embarazo , Cintigrafía , Estudios Retrospectivos , Obstrucción Ureteral/diagnóstico por imagen , Urografía
7.
Int J Nanomedicine ; 16: 1377-1390, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33658778

RESUMEN

Background: Vascular drug delivery becomes a promising direction in the development of novel therapeutic strategies in the treatment of cardiovascular pathologies, such as hypertension. However, targeted delivery of hydrophobic substances, with poor bioavailability, remains a challenge. Here, we described the hypotensive effects of a low dose of curcumin delivered to the vascular wall using hyaluronic acid-based nanocapsules. Methods: The group of hypertensive TGR(m-Ren2)27 rats, was administrated respectively with the vehicle, curcumin solution or curcumin delivered using hyaluronic acid-based nanocapsules (HyC12-Cur), for 7 days each, maintaining the wash-out period between treatments. Arterial blood pressure (systolic - SBP, diastolic - DBP) and heart rate (HR) were monitored continuously using a telemetry system (Data Science International), and Mean Arterial Pressure (MAP) was calculated from SBP and DBP. Results: In hypertensive rats, a low dose of curcumin (4.5 mg/kg) administrated in HyC12-Cur for 7 days resulted in a gradual inhibition of SBP, DBP and MAP increase without an effect on HR. At the end of HyC12-Cur - based treatment changes in SBP, DBP and MAP amounted to -2.0±0.8 mmHg, -3.9±0.7 mmHg and -3.3±0.7 mmHg, respectively. In contrast, the administration of a curcumin solution (4.5 mg/kg) did not result in a significant hypotensive effect and the animals constantly developed hypertension. Vascular delivery of capsules with curcumin was confirmed using newly developed fluorine-rich nanocapsules (HyFC10-PFOB) with a shell based on a HA derivative and similar size as HyC12-Cur. HyFC10-PFOB gave fluorine signals in rat aortas analyzed ex vivo with a 19F NMR technique after a single intragastric administration. Conclusion: These results suggest that nanocapsules based on hyaluronic acid, the ubiquitous glycosaminoglycan of the extracellular matrix and an integral part of endothelial glycocalyx, may represent a suitable approach to deliver hydrophobic, poorly bioavailable compounds, to the vascular wall.


Asunto(s)
Curcumina/administración & dosificación , Curcumina/uso terapéutico , Ácido Hialurónico/química , Hipertensión/tratamiento farmacológico , Nanocápsulas/química , Administración Oral , Animales , Aorta/efectos de los fármacos , Aorta/patología , Presión Sanguínea/efectos de los fármacos , Curcumina/farmacología , Diástole/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Flúor/química , Frecuencia Cardíaca/efectos de los fármacos , Hidrodinámica , Interacciones Hidrofóbicas e Hidrofílicas , Hipertensión/fisiopatología , Espectroscopía de Resonancia Magnética , Masculino , Tamaño de la Partícula , Ratas , Electricidad Estática , Sístole/efectos de los fármacos
8.
No Shinkei Geka ; 49(2): 349-355, 2021 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-33762456

RESUMEN

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes(MELAS)is the most dominant form of mitochondrial diseases, presenting with headaches, seizures, and stroke-like episodes. Stroke-like episodes is a distinguishing feature of MELAS. Symptoms appear before the age of 20 years in 65-76% of patients. For the clinical diagnosis of MELAS, evidence of lactate accumulation in the central nervous system is important. The radiographic features of MELAS are stroke-like lesions in the affected brain areas, primarily the occipito-parietal or posterior temporal lobe. MRI shows high signal intensities on T2-weighted or FLAIR images. The cerebral blood flow in lesions can be increased in the acute phase. MR spectroscopy(MRS)shows a lactate peak in the brain lesions, which is important evidence of lactate accumulation. In pediatric or young adult patients with occipito-parietal stroke-like lesions, a prominent lactate peak in MRS is the key radiographic sign that supports the diagnosis of MELAS.


Asunto(s)
Síndrome MELAS , Accidente Cerebrovascular , Adulto , Encéfalo , Niño , Humanos , Síndrome MELAS/diagnóstico , Síndrome MELAS/diagnóstico por imagen , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/etiología , Adulto Joven
9.
No Shinkei Geka ; 49(2): 368-374, 2021 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-33762459

RESUMEN

Although the prognosis of brain abscesses has historically improved, the mortality rate still ranges from 5 to 32%, with ventricular perforation reaching 50% and 85-100% in fungal brain abscesses. The characteristic finding of ring-like enhancement by contrast-enhanced imaging is non-specific, and DWI, SWI and MR spectroscopy are very useful in differentiating brain abcesses from necrotizing brain tumors. Brain abscesses show apparent diffusion restriction on the DWI/apparent diffusion coefficient(ADC) map, whereas necrotizing brain tumors often show a weak diffusion restriction. The "dual rim sign" on SWI is also a highly specific finding of brain abscess.


Asunto(s)
Absceso Encefálico , Neoplasias Encefálicas , Encéfalo , Absceso Encefálico/diagnóstico por imagen , Absceso Encefálico/cirugía , Neoplasias Encefálicas/diagnóstico por imagen , Diagnóstico Diferencial , Imagen de Difusión por Resonancia Magnética , Humanos , Espectroscopía de Resonancia Magnética
10.
No Shinkei Geka ; 49(2): 438-444, 2021 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-33762470

RESUMEN

Proton magnetic resonance spectroscopy(1H-MRS)is a non-invasive method for evaluating brain function and metabolism. 1H-MRS can quantify low-molecular-weight metabolites in a living brain; it shows their spectra without tracer administration. In this paper, we introduce 1H-MRS and MRS for imaging the distribution of metabolites. The applications of 1H-MRS imaging for several neurological disorders will be outlined.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Humanos , Espectroscopía de Resonancia Magnética , Espectroscopía de Protones por Resonancia Magnética
11.
Eur J Radiol ; 137: 109610, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33657474

RESUMEN

PURPOSE: Fatigue is a common symptom in patients with multiple sclerosis (MS) with unknown pathophysiology. Dysfunction of the GABAergic/glutamatergic pathways involving inhibitory and excitatory neurotransmitters such as  γ-aminobutyric acid (GABA) and glutamine + glutamate pool (Glx) have been implicated in several neurological disorders. This study is aimed to evaluate the potential role of GABA and Glx in the origin of central fatigue in relapse remitting MS (RRMS) patients. METHODS: 24 RRMS patients and 16 age- and sex-matched healthy controls (HC) were scanned using Mescher-Garwood point resolved spectroscopy (MEGA-PRESS) with a 3 T system to quantify GABA+ and Glx from prefrontal (PFC) and sensorimotor (SMC) cortices. Self-reported fatigue status was measured on all participants using the Modified Fatigue Impact Scale (MFIS). RESULTS: RRMS patients had higher fatigue scores relative to HC (p ≤  0.05). Compared to HC, Glx levels in RRMS patients were significantly decreased in SMC (p =  0.04). Significant correlations were found between fatigue scores and GABA+ (r = -0.531, p =  0.008) and Glx (r = 0.511, p =  0.018) in PFC. Physical fatigue was negatively correlated with GABA+ in SMC and PFC (r = -0.428 and -0.472 respectively, p ≤  0.04) and positively with PFC Glx (r = 0.480, p =  0.028). CONCLUSION: The associations between fatigue and GABA + and Glx suggest that there might be dysregulation of GABAergic/glutamatergic neurotransmission in the pathophysiological mechanism of central fatigue in MS.


Asunto(s)
Ácido Glutámico , Esclerosis Múltiple , Encéfalo/diagnóstico por imagen , Fatiga , Glutamina , Humanos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/diagnóstico por imagen , Ácido gamma-Aminobutírico
12.
J Vis Exp ; (168)2021 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-33720118

RESUMEN

Many major allergens bind to hydrophobic lipid-like molecules, including Mus m 1, Bet v 1, Der p 2, and Fel d 1. These ligands are strongly retained and have the potential to influence the sensitization process either through directly stimulating the immune system or altering the biophysical properties of the allergenic protein. In order to control for these variables, techniques are required for the removal of endogenously bound ligands and, if necessary, replacement with lipids of known composition. The cockroach allergen Bla g 1 encloses a large hydrophobic cavity which binds a heterogeneous mixture of endogenous lipids when purified using traditional techniques. Here, we describe a method through which these lipids are removed using reverse-phase HPLC followed by thermal annealing to yield Bla g 1 in either its Apo-form or reloaded with a user-defined mixture of fatty acid or phospholipid cargoes. Coupling this protocol with biochemical assays reveal that fatty acid cargoes significantly alter the thermostability and proteolytic resistance of Bla g 1, with downstream implications for the rate of T-cell epitope generation and allergenicity. These results highlight the importance of lipid removal/reloading protocols such as the one described herein when studying allergens from both recombinant and natural sources. The protocol is generalizable to other allergen families including lipocalins (Mus m 1), PR-10 (Bet v 1), MD-2 (Der p 2) and Uteroglobin (Fel d 1), providing a valuable tool to study the role of lipids in the allergic response.


Asunto(s)
Alérgenos/metabolismo , Lípidos/química , Proteínas/metabolismo , Alérgenos/aislamiento & purificación , Animales , Cromatografía Líquida de Alta Presión , Cucarachas , Hipersensibilidad/inmunología , Ligandos , Espectroscopía de Resonancia Magnética , Fosfolípidos/química , Unión Proteica , Pliegue de Proteína , Reproducibilidad de los Resultados
13.
Carbohydr Polym ; 260: 117801, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712149

RESUMEN

Slowly digestible starches have received interest due to their lower increase of postprandial blood glucose and insulin levels and, hence, modification of starches towards slower digestibility has commercial interest. However, chemical characteristics driving enzymatic (digestive) degradation are not fully unraveled. The digestion properties of starches have been linked to their crystalline type, chain length distribution, amylose content or degree of branching, but content and length of relatively long side-chains in amylopectin has not been paid attention to. Therefore, this research focusses on the unique content and length of amylopectin side-chains from conventional and new starch sources (potato, corn, pea, and tulip) correlated to the enzymatic digestion. The rate of hydrolysis was found to be correlated with the crystalline type of starch, as previously suggested, however, the complete hydrolysis of all starches, independent of the crystalline type and source, was shown to be governed by the content of longer amylopectin chains.


Asunto(s)
Gelatina/química , Glucano 1,4-alfa-Glucosidasa/metabolismo , Almidón/metabolismo , alfa-Amilasas/metabolismo , Cristalización , Digestión , Hidrólisis , Espectroscopía de Resonancia Magnética , Guisantes/metabolismo , Solanum tuberosum/metabolismo , Almidón/química , Zea mays/metabolismo
14.
Carbohydr Polym ; 260: 117825, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712166

RESUMEN

Polysaccharide ASK was isolated from the Abies sibirica foliage by extraction with an aqueous KOH solution. ASK was shown to contain structurally different polymers such as arabinoglucuronoxylans, xyloglucans, glucomannans, arabinogalactan-proteins (AGPs). The pectic polysaccharides were also found in the alkaline extract of ASK and were represented by regions of homogalactorunan and rhamnogalactouronan-I whose side sugar chains were made up chiefly of highly branched 1,5-α-l-arabinan. The potential couplings between those polysaccharides were examined. Our studies showed simultaneous elution of pectin, xyloglucans, arabinoglucuronoxylans and AGPs, indicating that pectins can be covalently bound to the other cell-wall polysaccharides. NMR spectroscopy results revealed that the polysaccharides obtained by ion-exchange chromatography almost had no free reducing ends. These findings corroborate the conclusion that pectin, AGPs, glucan and xylan are bound together. The existence of the covalently bound complex of pectin-xylan-xyloglucan-AGP is suggested herein. Pectin and xylan are hypothesized to be covalently linked through RG-I regions.


Asunto(s)
Abies/metabolismo , Glucanos/química , Mucoproteínas/química , Pectinas/química , Polisacáridos/análisis , Xilanos/química , Hidrólisis , Espectroscopía de Resonancia Magnética , Peso Molecular , Proteínas de Plantas/química , Polisacáridos/metabolismo , Siberia
15.
Molecules ; 26(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33668752

RESUMEN

Polyvinyl chloride (PVC), one of the most important polymer materials nowadays, has a large variety of formulations through the addition of various plasticizers to meet the property requirements of the different fields of applications. Routine analytical methods able to identify plasticizers and quantify their amount inside a PVC product with a high analysis throughput would promote an improved understanding of their impact on the macroscopic properties and the possible health and environmental risks associated with plasticizer leaching. In this context, a new approach to identify and quantify plasticizers employed in PVC commodities using low-field NMR spectroscopy and an appropriate non-deuterated solvent is introduced. The proposed method allows a low-cost, fast, and simple identification of the different plasticizers, even in the presence of a strong solvent signal. Plasticizer concentrations below 2 mg mL-1 in solution corresponding to 3 wt% in a PVC product can be quantified in just 1 min. The reliability of the proposed method is tested by comparison with results obtained under the same experimental conditions but using deuterated solvents. Additionally, the type and content of plasticizer in plasticized PVC samples were determined following an extraction procedure. Furthermore, possible ways to further decrease the quantification limit are discussed.


Asunto(s)
Plastificantes/análisis , Cloruro de Polivinilo/análisis , Espectroscopía de Resonancia Magnética , Estructura Molecular , Plastificantes/economía , Cloruro de Polivinilo/economía
16.
Molecules ; 26(4)2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33669887

RESUMEN

In the last few years, a new term, "High-phenolic olive oil", has appeared in scientific literature and in the market. However, there is no available definition of that term regarding the concentration limits of the phenolic ingredients of olive oil. For this purpose, we performed a large-scale screening and statistical evaluation of 5764 olive oil samples from Greece coming from >30 varieties for an eleven-year period with precisely measured phenolic content by qNMR. Although there is a large variation among the different cultivars, the mean concentration of total phenolic content was 483 mg/kg. The maximum concentration recorded in Greece reached 4003 mg/kg. We also observed a statistically significant correlation of the phenolic content with the harvest period and we also identified varieties affording olive oils with higher phenolic content. In addition, we performed a study of phenolic content loss during usual storage and we found an average loss of 46% in 12 months. We propose that the term high-phenolic should be used for olive oils with phenolic content > 500 mg/kg that will be able to retain the health claim limit (250 mg/kg) for at least 12 months after bottling. The term exceptionally high phenolic olive oil should be used for olive oil with phenolic content > 1200 mg/kg (top 5%).


Asunto(s)
Espectroscopía de Resonancia Magnética , Aceite de Oliva/química , Fenoles/análisis , Estadística como Asunto , Aldehídos/análisis , Monoterpenos Ciclopentánicos/análisis , Grecia , Fenoles/química , Preservación Biológica
17.
Molecules ; 26(4)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670094

RESUMEN

Unapproved ingredients included in herbal medicines and dietary supplements have been detected as adulterated synthetic drugs used for erectile dysfunction. Extraction from a dietary supplement was performed to isolate the compounds by HPLC analysis. The structural characterization was confirmed using mass spectrometry (ESI-TOF/MS and LC-MS/MS), 1H NMR, and 13C NMR spectroscopy techniques. Results identified the thus-obtained compound to be sulfoaildenafil, a thioketone analogue of sildenafil. The biological activities of this active compound have been focused for the first time by the experimental point of view performance in vitro. The results revealed that sulfoaildenafil can affect the therapeutic level of nitric oxide through the upregulation of nitric oxide synthase and phosphodiesterase type 5 (PDE5) gene expressions. This bulk material, which displays structural similarity to sildenafil, was analyzed for the presence of a PDE5 inhibitor using a theoretical calculation. These unique features of the potential activity of PDE5 protein and its inhibitors, sildenafil and sulfoaildenafil, may play a key consideration for understanding the mode of actions and predicting the biological activities of PDE5 inhibitors.


Asunto(s)
Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/genética , Suplementos Dietéticos , Disfunción Eréctil/tratamiento farmacológico , Inhibidores de Fosfodiesterasa 5/química , Cromatografía Líquida de Alta Presión , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/química , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 5/efectos de los fármacos , Disfunción Eréctil/patología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Medicina de Hierbas , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Espectrometría de Masas , Modelos Moleculares , Estructura Molecular , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Piperazinas/química , Piperazinas/uso terapéutico , Citrato de Sildenafil/química , Citrato de Sildenafil/uso terapéutico , Sulfonas/química , Sulfonas/uso terapéutico
18.
Molecules ; 26(4)2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33670502

RESUMEN

Promising research over the past decades has shown that some types of pentacyclic triterpenes (PTs) are associated with the prevention of type 2 diabetes (T2D), especially those found in foods. The most abundant edible sources of PTs are those belonging to the ursane and oleanane scaffold. The principal finding is that Cecropia telenitida contains abundant oleanane and ursane PT types with similar oxygenation patterns to those found in food matrices. We studied the compositional profile of a rich PT fraction (DE16-R) and carried out a viability test over different cell lines. The biosynthetic pathway connected to the isolated PTs in C. telenitida offers a specific medicinal benefit related to the modulation of T2D. This current study suggests that this plant can assemble isobaric, positional isomers or epimeric PT. Ursane or oleanane scaffolds with the same oxygenation pattern are always shared by the PTs in C. telenitida, as demonstrated by its biosynthetic pathway. Local communities have long used this plant in traditional medicine, and humans have consumed ursane and oleanane PTs in fruits since ancient times, two key points we believe useful in considering the medicinal benefits of C. telenitida and explaining how a group of molecules sharing a closely related scaffold can express effectiveness.


Asunto(s)
Vías Biosintéticas , Cecropia (Planta)/química , Suplementos Dietéticos , Triterpenos Pentacíclicos/metabolismo , Animales , Muerte Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Fraccionamiento Químico , Cromatografía Líquida de Alta Presión , Humanos , Espectroscopía de Resonancia Magnética , Ratones , Triterpenos Pentacíclicos/química , Triterpenos Pentacíclicos/farmacología
19.
Molecules ; 26(4)2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33670764

RESUMEN

Phytochemical investigation of leaves and stembark of Artocarpus lacucha collected in Thailand resulted in three yet undescribed isomeric flavan-3-ol derivatives (1-3), the four known compounds gambircatechol (4), (+)-catechin (5), (+)-afzelechin (6) and the stilbene oxyresveratrol (7). Compounds 1 to 3 feature 6/6/5/6/5/6 core structures. All structures were deduced by NMR and MS, while density functional theory (DFT) calculations on B3LYP theory level were performed of compounds 1 to 3 to support the stereochemistry in positions 2 and 3 in the C-ring. Possible biosynthetic pathways leading to 4 are discussed. The DPPH assay revealed high radical scavenging activities for 1 (EC50 = 9.4 ± 1.0 µmol mL-1), 2 (12.2 ± 1.1), 3 (10.0 ± 1.5) and 4 (19.0 ± 2.6), remarkably lower than ascorbic acid (EC50 = 34.9) and α-tocopherol (EC50 = 48.6). A cytotoxicity assay revealed moderate but consistent antiproliferative properties of 1 in CH1/PA-1 (ovarian teratocarcinoma) and SW480 (colon carcinoma) cells, with IC50 values of 25 ± 6 and 34 ± 4 µM, respectively, whereas effects in A549 (non-small cell lung cancer) cells were rather negligible. The performed DCFH-DA assay of 1 in the former cell lines confirmed potent antioxidative effects even in the cellular environment.


Asunto(s)
Artocarpus/química , Flavonoides/farmacología , Depuradores de Radicales Libres/farmacología , Antioxidantes/farmacología , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Simulación por Computador , Flavonoides/química , Humanos , Espectroscopía de Resonancia Magnética , Conformación Molecular , Oxidación-Reducción , Estereoisomerismo
20.
Molecules ; 26(4)2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33673291

RESUMEN

Isocyanoazulenes (CNAz) constitute a relatively new class of isocyanoarenes that offers rich structural and electronic diversification of the organic isocyanide ligand platform. This article considers a series of 2-isocyano-1,3-X2-azulene ligands (X = H, Me, CO2Et, Br, and CN) and the corresponding zero-valent complexes thereof, [(OC)5Cr(2-isocyano-1,3-X2-azulene)]. Air- and thermally stable, X-ray structurally characterized 2-isocyano-1,3-dimethylazulene may be viewed as a non-benzenoid aromatic congener of 2,6-dimethyphenyl isocyanide (2,6-xylyl isocyanide), a longtime "workhorse" aryl isocyanide ligand in coordination chemistry. Single crystal X-ray crystallographic {Cr-CNAz bond distances}, cyclic voltametric {E1/2(Cr0/1+)}, 13C NMR {δ(13CN), δ(13CO)}, UV-vis {dπ(Cr) → pπ*(CNAz) Metal-to-Ligand Charge Transfer}, and FTIR {νN≡C, νC≡O, kC≡O} analyses of the [(OC)5Cr(2-isocyano-1,3-X2-azulene)] complexes provided a multifaceted, quantitative assessment of the π-acceptor/σ-donor characteristics of the above five 2-isocyanoazulenes. In particular, the following inverse linear relationships were documented: δ(13COtrans) vs. δ(13CN), δ(13COcis) vs. δ(13CN), and δ(13COtrans) vs. kC≡O,trans force constant. Remarkably, the net electron withdrawing capability of the 2-isocyano-1,3-dicyanoazulene ligand rivals those of perfluorinated isocyanides CNC6F5 and CNC2F3.


Asunto(s)
Cianuros/química , Electrones , Compuestos Heterocíclicos/química , Isotiocianatos/química , Azulenos/química , Cristalografía por Rayos X , Ligandos , Espectroscopía de Resonancia Magnética , Metales/química , Modelos Moleculares , Estructura Molecular
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