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1.
Int J Mol Sci ; 25(1)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38203833

RESUMEN

The gut microbiome is well known for its influence on human physiology and aging. Therefore, we speculate that the gut microbiome may affect muscle strength in the same way as the host's own genes. To demonstrate candidates for gut microbes affecting muscle strength, we remodeled the original gut microbiome of mice into human intestinal microbiome through fecal microbiome transplantation (FMT), using human feces and compared the changes in muscle strength in the same mice before and three months after FMT. After comparing before and after FMT, the mice were divided into three groups based on the observed changes in muscle strength: positive, none, and negative changes in muscle strength. As a result of analyzing the α-diversity, ß-diversity, and co-occurrence network of the intestinal microbial community before and after FMT, it was observed that a more diverse intestinal microbial community was established after FMT in all groups. In particular, the group with increased muscle strength had more gut microbiome species and communities than the other groups. Fold-change comparison showed that Eisenbergiella massiliensis and Anaeroplasma abactoclasticum from the gut microbiome had positive contributions to muscle strength, while Ileibacterium valens and Ethanoligenens harbinense had negative effects. This study identifies candidates for the gut microbiome that contribute positively and those that contribute negatively to muscle strength.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Humanos , Animales , Ratones , Trasplante de Microbiota Fecal , Heces , Fuerza Muscular
2.
Vet Ophthalmol ; 26(4): 324-330, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36840613

RESUMEN

OBJECTIVE: We aimed to track and evaluate the association between vitreous degeneration and the development of cataracts or retinal detachments in dogs over a long period. ANIMAL STUDIED: Data on vitreous degeneration, cataracts, and retinal detachment in 102 eyes were collected from 68 dogs who underwent ocular ultrasonography at least twice between March 2017 and November 2021 at the Veterinary Medical Teaching Hospital, Konkuk University. The mean follow-up time was 515 ± 256 (mean ± standard deviation; range: 81-1196) days. PROCEDURE: Development of cataracts and retinal detachment, according to the severity of vitreous degeneration grade (VDG), was evaluated during long-term follow-up. RESULTS: In the cataract study (87 eyes, 61 dogs), the number of cataracts developed according to VDG (grade: 0-3) were as follows: VDG 0: 1 in 10 (10%) eyes, VDG 1: 15 in 35 (43%) eyes, VDG 2: 15 in 30 (50%) eyes, and VDG 3: 10 in 12 (83%) eyes. It was significantly different among grades (p = .026). In the retinal detachment study (95 eyes, 64 dogs), the number of retinal detachments developed according to each VDG were as follows: VDG 0: 0 in 11 (0%) eyes, VDG 1: 1 in 36 (3%) eyes, VDG 2: 5 in 35 (14%) eyes, and VDG 3: 4 in 13 (30%) eyes. It was also significantly different among grades (p = .019). CONCLUSIONS: During long-term follow-up, dogs with severe vitreous degeneration had an increased risk of cataract and retinal detachment development than those without or with mild vitreous degeneration.


Asunto(s)
Catarata , Enfermedades de los Perros , Desprendimiento de Retina , Perros , Animales , Desprendimiento de Retina/etiología , Desprendimiento de Retina/veterinaria , Ojo/diagnóstico por imagen , Catarata/complicaciones , Catarata/veterinaria , Agudeza Visual , Ultrasonografía , Enfermedades de los Perros/etiología
3.
Mol Cell ; 56(3): 343-344, 2014 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-25514180

RESUMEN

Metabolic reprogramming is a characteristic of cancer cells. Three studies published in this month's Molecular Cell provide novel insights into the role of mitochondrial pyruvate in tumor metabolism and describe how targeting pyruvate transport and metabolism may afford therapeutic benefit.


Asunto(s)
Mitocondrias/metabolismo , Neoplasias/metabolismo , Ácido Pirúvico/metabolismo , Transporte Biológico , Glucólisis , Humanos , Terapia Molecular Dirigida , Neoplasias/tratamiento farmacológico , Neoplasias/patología
4.
Vet Ophthalmol ; 24(4): 391-399, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34240540

RESUMEN

OBJECTIVE: To prospectively assess the efficacy of a biodegradable collagen matrix (ologen) in dogs with uncontrolled glaucoma receiving an Ahmed glaucoma valve (AGV) implant. ANIMAL STUDIED: Five client-owned dogs with glaucoma (five eyes). PROCEDURES: Five eyes treated for uncontrolled glaucoma underwent AGV implantation with ologen. Ologen was placed on the AGV plate and tube with a scleral flap. Complete ophthalmological examinations were performed preoperatively and at 1 and 3 days, 1 and 2 weeks, and 1, 2, 3, and 6 months postoperatively. Surgical outcomes were assessed based on the intraocular pressure (IOP), vision, frequency of anti-glaucoma eye drops, and bleb morphology; complications, if any, were recorded. The number of dogs with an IOP <20 mmHg with or without topical medications were tabulated and compared to those with an IOP ≥20 mmHg or those requiring surgery to maintain the IOP at <20 mmHg. RESULTS: The IOP significantly decreased from 47.00 ± 5.09 mmHg preoperatively to 17.00 ± 0.71 mmHg 6 months postoperatively (p = .008). IOP was controlled (<20 mmHg) in 5/5 dogs at 6 months postoperatively. Brief periods of elevated IOP (IOP ≥ 20 mmHg, IOP spike) occurred in one eye (case 5) at 1 month (35 mmHg) and 2 months (33 mmHg) postoperatively. The anti-glaucoma eye drop frequency decreased from 3.2 ± 0.44 preoperatively to 1.6 ± 0.90 at 6 months postoperatively (p = .007). CONCLUSIONS: To our knowledge, this is the first study to assess the potential safety of AGV implantation with ologen for canine glaucoma. This method effectively controlled the IOP, without any adverse effects.


Asunto(s)
Colágeno/uso terapéutico , Enfermedades de los Perros/tratamiento farmacológico , Implantes de Drenaje de Glaucoma/veterinaria , Glaucoma/veterinaria , Glicosaminoglicanos/uso terapéutico , Animales , Colágeno/efectos adversos , Enfermedades de los Perros/cirugía , Perros , Femenino , Glaucoma/cirugía , Glicosaminoglicanos/efectos adversos , Presión Intraocular/efectos de los fármacos , Masculino , Estudios Prospectivos , Resultado del Tratamiento
5.
ChemSusChem ; 17(7): e202301044, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38030584

RESUMEN

A crystalline supramolecular photocatalyst is prepared through metal-induced self-assembly of perylene diimide with imidazole groups at the imide position (PDI-Hm). Exploiting the metal-coordination ability of imidazole, a crystalline assembly of copper-coordinated PDI-Hm (CuPDI-Hm) in a nanorod shape is prepared which displays an outstanding photocatalytic oxygen evolution rate of 25,900 µmol g-1 h-1 without additional co-catalysts. The imidazole-copper coordination, along with π-π stacking of PDI frameworks, guides the arrangement of PDI-Hm molecules to form highly crystalline assemblies. The coordination of copper also modulates the size of the CuPDI-Hm supramolecular assembly by regulating the nucleation and growth processes. Furthermore, the imidazole-copper coordination constructs the electric field within the PDI-Hm assembly, hindering the recombination of photo-induced charges to enhance the photoelectric/photocatalytic activity when compared to Cu-free PDI-Hm assemblies. Small CuPDI-Hm assembly exhibits higher photocatalytic activity due to their larger surface area and reduced light scattering. Together, the Cu-imidazole coordination presents a facile way for fabricating size-controlled crystalline PDI assemblies with built-in electric field enhancing photoelectric and photocatalytic activities substantially.

6.
Exp Parasitol ; 134(2): 235-43, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23541983

RESUMEN

Members of the ATP-binding cassette (ABC)-type transporter superfamily have been implicated in multidrug resistance in malaria, and various mechanistic models have been postulated to explain their interaction with diverse antimalarial drugs. To gain insight into the pharmacological benefits of inhibiting ABC-type transporters in malaria chemotherapy, we investigated the in vitro chemosensitization potential of various P-glycoprotein inhibitors. A fluorescent chloroquine derivative was synthesized and used to assess the efflux dynamics of chloroquine in MDR and wild type Plasmodium falciparum parasites. This novel BODIPY-based probe accumulated in the digestive vacuole (DV) of CQ-sensitive parasites but less so in MDR cells. Pre-exposure of the MDR parasites to non-cytocidal concentrations of unlabeled chloroquine resulted in a diffused cytoplasmic retention of the probe whereas a similar treatment with the CQR-reversing agent, chlorpheniramine, resulted in DV accumulation. A diffused cytoplasmic distribution of the probe was also obtained following treatment with the P-gp specific inhibitors zosuquidar and tariquidar, whereas treatments with the tyrosine kinase inhibitors gefitinib or imatinib produced a partial accumulation within the DV. Isobologram analyses of the interactions between these inhibitors and the antimalarial drugs chloroquine, mefloquine, and artemisinin revealed distinct patterns of drug synergism, additivity and antagonism. Taken together, the data indicate that competitive tyrosine kinase and noncompetitive P-glycoprotein ATPase-specific inhibitors represent two new classes of chemosensitizing agents in malaria parasites, but caution against the indiscriminate use of these agents in antimalarial drug combinations.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Antimaláricos/farmacología , Plasmodium falciparum/efectos de los fármacos , Artemisininas/farmacología , Benzamidas/farmacología , Compuestos de Boro/química , Cloroquina/farmacología , Clorfeniramina/farmacología , Dibenzocicloheptenos/farmacología , Interacciones Farmacológicas , Resistencia a Múltiples Medicamentos , Eritrocitos/parasitología , Colorantes Fluorescentes/química , Gefitinib , Humanos , Mesilato de Imatinib , Mefloquina/farmacología , Piperazinas/farmacología , Plasmodium falciparum/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/farmacología , Quinazolinas/farmacología , Quinolinas/farmacología
7.
Animals (Basel) ; 13(21)2023 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-37958114

RESUMEN

Sequential pattern mining (SPM) is a data mining technique used for identifying common association rules in multiple sequential datasets and patterns in ordered events. In this study, we aimed to identify the relationships between commonly occurring internal medicine diseases in canine patients. We obtained medical records of dogs referred to the Konkuk University Veterinary Medicine Teaching Hospital. The data used for SPM included comorbidities and intervals between the diagnoses of internal medicine diseases. Additionally, we estimated the 3-year risk of developing an additional disease after the initial diagnosis of a commonly occurring veterinary internal medicine disease using logistic regression. We identified 547 canine patients diagnosed with ≥ 1 internal medicine disease. The SPM-based analysis assessed comorbidities and intervals for each of the five most common internal medical diseases, including hyperadrenocorticism, myxomatous mitral valve disease, canine atopic dermatitis, chronic kidney disease, and chronic pancreatitis. The highest values of the association rule were 3.01%, 6.02%, 3.9%, 4.1%, and 4.84%, and the shortest intervals were 1.64, 13.14, 5.37, 17.02, and 1.7 days, respectively. This study proposes that SPM is an effective technique for identifying common associations and temporal relationships between internal medicine diseases, and can be used to assess the probability of additional admission due to the development of the subsequent disease that may be diagnosed in canine patients. The results of this study will help veterinarians suggest appropriate preventive measures or other medical treatments for canine patients with medical conditions that have not yet been diagnosed, but are likely to develop in the short term.

8.
Ann Lab Med ; 43(2): 174-179, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36281511

RESUMEN

Background: Development of an accessible method to routinely evaluate the clonality of strains is needed in microbiology laboratories. We compared the discriminatory power of the Fourier-transform infrared (FTIR) spectroscopy-based IR Biotyper (Bruker Daltonics GmbH, Bremen, Germany) to matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), using whole-genome sequencing (WGS) as the reference method. Methods: Eighty-three extended-spectrum ß-lactamase-producing Escherichia coli isolates were tested using WGS, MALDI-TOF MS, and IR Biotyper. Simpson's diversity index (SDI), a statistical analysis for testing the homogeneity of a dendrogram, and the adjusted Rand index (aRI) were used to compare the discriminatory ability between typing tests. Results: The SDI (95% confidence interval) was 0.969 (0.952-0.985) for WGS, 0.865 (0.807-0.924) for MALDI-TOF MS, and 0.974 (0.965-0.983) for IR Biotyper. Compared with WGS, IR Biotyper showed compatible diversity, whereas MALDI-TOF MS did not. The concordance and aRI improved from 66.3% to 84.3% and from 0.173 to 0.538, respectively, for IR Biotyper versus MALDI-TOF MS with WGS as the reference method. IR Biotyper showed substantially improved performance in strain typing compared with MALDI-TOF MS. Conclusions: IR Biotyper is useful for diversity analysis with improved discriminatory power over MALDI-TOF MS in comparison with WGS as a reference method. IR Biotyper is an accessible method to evaluate the clonality of strains and could be applied in epidemiological analysis during an outbreak of a health care facility, as well as for research on the transmission of resistant bacteria in community settings.


Asunto(s)
Bacterias , Escherichia coli , Humanos , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Bacterias/genética , Escherichia coli/genética , beta-Lactamasas/genética , Rayos Láser
9.
Chem Phys Lipids ; 242: 105164, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34906552

RESUMEN

The selection of an animal model is based on the pathological mechanism appropriate for experimental investigation because the therapeutic effect was low depending on the pathological occurrence mechanism. The purpose of this study is to elucidate the changes in lipid proton concentration in two animal models of nonalcoholic fatty liver disease (NAFLD): methionine and choline-deficient (MCD) diet and high-fat diet (HFD). We calculated the T2 relaxation time of 7 lipid protons (LP) in the 9.4 T MRS phantom experiment. The concentrations of LPs were adjusted for T2 and T2* of MCD, HFD, and CCl4 fatty liver animal models. Multivariate analysis and Pearson correlation were performed to analyze LP concentration, and the difference was investigated via Kendall correlation and independent t-test using LP composition ratio. The T2 relaxation time of each LP was accurately determined using phantom experiments. The in vivo magnetic resonance spectroscopy (MRS) data were obtained by quantifying the t2/t2* corrected LP concentration in the liver of the animal model. In case of MCD and HFD, there was an average difference in all LPs except 0.9 ppm LP, and the MCD and CCl4 groups showed differences in the average of all LPs. However, there was no difference between LP of HFD and CCl4 groups. A higher level of unsaturated fatty acids was found in the MCD fatty liver model than in HFD induced fatty liver.


Asunto(s)
Metionina , Enfermedad del Hígado Graso no Alcohólico , Animales , Colina , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Lípidos , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Protones
10.
Microsc Res Tech ; 85(11): 3623-3632, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35916360

RESUMEN

The type and ratio of abnormal red blood cells (RBCs) in blood can be identified through peripheral blood smear test. Accurate classification is important because the accompanying diseases indicated by abnormal RBCs vary. In clinical practice, this task is time-consuming because the RBCs are manually classified. In addition, because the classification depends on the subjective criteria of pathologists, objective classification is difficult to achieve. In this paper, an automatic classification method that is solely based on images of RBCs captured under a microscope and processed using machine learning (ML) is proposed. The size and hemoglobin abnormalities of RBCs were classified by optimizing the criteria used in clinical practice. For morphologically abnormal RBCs classification, used seven geometric features information (major axis, minor axis, ratio of major and minor axis, perimeter, circularity, number of convex hulls, difference between area and convex area) and five types of multiple classifiers (Support Vector Machine, Decision Tree, K-Nearest Neighbor, Random Forest, and Adaboost models). Among was categorized using SVM, highly accurate results (99.9%) were obtained. The classification is performed simultaneously, and results are provided to the user through a graphical user interface (GUI).


Asunto(s)
Aprendizaje Automático , Máquina de Vectores de Soporte , Algoritmos , Eritrocitos , Microscopía
11.
Microsc Res Tech ; 85(1): 364-372, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34453869

RESUMEN

Preclinical experiments to analyze the trabecular space of spongy bones using small animals are required for the evaluation and treatment of patients with osteoporosis (OP). We performed ovariectomy to create OP models. A total of four mice were used. Ovariectomized group (OVX, n = 2) in which both ovaries were resected at random, and the sham operated group (SHAM, n = 2) performed surgery without resecting the ovaries. We propose a study that enables OP analysis by analyzing tibia microstructures of OVX and SHAM using synchrotron radiation (SR). SR imaging is a technology capable of irradiating an extremely small object in the order of several tens of nanometers using a nondestructive method at the microscopic level. Unlike previous imaging diagnoses (staining, micro-CT [Computed Tomography]) it was possible to preserve the real shape and analyze bone microstructures in real-time and analyze and evaluate spongy bones to secure data and increase the reliability of OP analysis. We were able to confirm the possibility of OP diagnosis through experimental animals for spongy bone damage related to bone mineral density. Therefore, we aimed to provide a rehabilitation and medicine therapy intervention method through basic research on the evaluation of OP diagnosis through human-based segmentation of challenging spongy bones while supplementing the limitations of existing imaging methods. RESEARCH HIGHLIGHTS: We present an analysis of osteoporosis through spongy bone using phase-contrast X-ray source. Unlike existing methods, it is possible to analyze the internal microstructure of the tibia with this method. This is an objective mechanism for OP and a basis for rehabilitation.


Asunto(s)
Osteoporosis , Sincrotrones , Animales , Densidad Ósea , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Modelos Animales , Osteoporosis/diagnóstico por imagen , Ovariectomía , Reproducibilidad de los Resultados , Tibia/diagnóstico por imagen , Microtomografía por Rayos X
12.
J Clin Med ; 11(12)2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35743492

RESUMEN

According to previous studies, the increased risk of cutaneous infectious disorders in patients with atopic dermatitis (AD) is related to impaired epidermal function, abnormal systemic immune function, and lower antimicrobial peptides. In this study, we analyzed the association between AD and cutaneous infectious disorders in the real world using sequential pattern mining (SPM). We analyzed National Health Insurance data from 2010-2013 using SPM to identify comorbid cutaneous infectious diseases and the onset durations of comorbidities. Patients with AD were at greater risk for molluscum contagiosum (adjusted odds ratio (aOR), 5.273), impetigo (aOR, 2.852), chickenpox (aOR, 2.251), otitis media (aOR, 1.748), eczema herpeticum (aOR, 1.292), and viral warts (aOR, 1.105). In SPM analysis, comorbidity of 1.06% shown in molluscum contagiosum was the highest value, and the duration of 77.42 days documented for molluscum contagiosum was the shortest onset duration among all the association rules. This study suggests that AD is associated with an increased risk of cutaneous infectious disorders. In particular, care should be taken regarding its high relevance with impetigo, molluscum contagiosum, and otitis media, which may help in preventing AD from worsening through appropriately preventing and managing the condition.

13.
Adv Genet (Hoboken) ; 2(2)2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34423307

RESUMEN

Regeneration is widespread across the animal kingdom but varies vastly across phylogeny and even ontogeny. Adult mammalian regeneration in most organs and appendages is limited, while vertebrates such as zebrafish and salamanders are able to regenerate various organs and body parts. Here, we focus on the regeneration of appendages, spinal cord, and heart - organs and body parts that are highly regenerative among fish and amphibian species but limited in adult mammals. We then describe potential genetic, epigenetic, and post-transcriptional similarities among these different forms of regeneration across vertebrates and discuss several theories for diminished regenerative capacity throughout evolution.

14.
Microscopy (Oxf) ; 70(5): 469-475, 2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34002795

RESUMEN

Until now, studies on nail diseases have been performed through microscopic diagnosis and microscopic computed tomography (micro-CT). However, these kinds of conventional methods have some limitations. Firstly, the microscopic method is considered the gold standard for medical diagnosis. However, due to the use of fluorescent materials, the sample is damaged and it takes a long time to get results. Secondly, while micro-CT is a noninvasive method to get inner structure images of the sample with high resolution, the penetration and spatial resolution are insufficient for studying the microstructures of the sample, such as the sponge bone and the muscle fibers. In contrast, synchrotron radiation (SR) X-ray imaging technology has the advantage of very vividly demonstrating the anatomic structure of the sample with high penetration, sensitivity and resolution. In this study, we compared the optical microscopic method using hematoxylin and eosin staining and SR imaging to analyze the nail tissue in a mouse model. The results showed that SR could depict the inner structures of a mouse nail without any physical damage. Additionally, we could divide the important anatomical structures of the nail unit into three parts with three-dimensional (3D) images: the nail bed, nail matrix and hyponychium. The images showed that SR could be used for analyzing nails by visualizing the relatively clear and medically semantic structures in a 3D section. We expect that the results of this study will be applied to study nail diseases and conduct pharmaceutical research on their treatment.


Asunto(s)
Pezuñas y Garras/anatomía & histología , Sincrotrones , Animales , Ratones , Microscopía , Enfermedades de la Uña , Coloración y Etiquetado
15.
Sci Rep ; 10(1): 4555, 2020 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-32165699

RESUMEN

Damage to lower limb muscles requires accurate analysis of the muscular condition via objective microscopic diagnosis. However, microscopic tissue analysis may cause deformation of the tissue structure due to injury induced by external factors during tissue sectioning. To substantiate these muscle injuries, we used synchrotron X-ray imaging technology to project extremely small objects, provide three-dimensional microstructural analysis as extracted samples. In this study, we used mice as experimental animals to create soleus muscle models with various nerve injuries. We morphologically analyzed and quantified the damaged Section and Crush muscles, respectively, via three-dimensional visualization using synchrotron radiation X-ray imaging to diagnose muscle injury. Results of this study can also be used as basic data in the medical imaging field.


Asunto(s)
Imagenología Tridimensional/métodos , Músculo Esquelético/inervación , Nervio Ciático/diagnóstico por imagen , Nervio Ciático/lesiones , Animales , Masculino , Ratones , Músculo Esquelético/diagnóstico por imagen , Radiografía , Sincrotrones , Rayos X
16.
Acad Radiol ; 25(12): 1595-1602, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29803754

RESUMEN

RATIONALE AND OBJECTIVES: The aim of this study was to determine the optimal weighting factor (WF) for precise quantification using six-point interference Dixon fat percentage imaging by analyzing changes in WFs of fatty acid metabolites (FMs) in high-fat-induced fatty liver disease rat model. MATERIALS AND METHODS: Individual FM-related WFs were calculated based on concentration ratios of integrated areas of seven peak FMs with four phantom series. Ten 8-week-old male Sprague-Dawley rats were used for baseline quantification of fat in liver magnetic resonance imaging or magnetic resonance spectroscopy data. These seven lipid metabolites were then quantitatively analyzed. Spearman test was used for correlation analysis of different lipid proton concentrations. The most accurate WF for six-point interference Dixon fat percentage imaging was then determined. RESULTS: The seven lipid resonance WF values obtained from magnetic resonance spectroscopy data for three different oils (oleic, linoleic, and soybean) were different from each other. In lipid phantoms, except for the phantom containing oleic acid, changes in FP values were significantly different when WFs were changed in six-point interference Dixon fat percentage image. The seven lipid resonance WF values for the nonalcoholic fatty liver animal model were different from human subcutaneous adipose tissue lipid WF values. CONCLUSIONS: WF affected the calculation of six-point interference Dixon-based fat percentage imaging value in phantom experiment. If WF of liver parenchyma FM which is specific to each liver disease is applied, the accuracy of six-point interference Dixon fat percentage imaging can be further increased.


Asunto(s)
Tejido Adiposo/diagnóstico por imagen , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Tejido Adiposo/patología , Animales , Modelos Animales de Enfermedad , Ácido Linoleico/metabolismo , Masculino , Ácido Oléico/metabolismo , Fantasmas de Imagen , Ratas , Ratas Sprague-Dawley , Aceite de Soja/metabolismo
17.
Int J Parasitol Drugs Drug Resist ; 7(1): 120-129, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28285258

RESUMEN

Drugs against malaria are losing their effectiveness because of emerging drug resistance. This underscores the need for novel therapeutic options for malaria with mechanism of actions distinct from current antimalarials. To identify novel pharmacophores against malaria we have screened compounds containing structural features of natural products that are pharmacologically relevant. This screening has identified a 4-nitro styrylquinoline (SQ) compound with submicromolar antiplasmodial activity and excellent selectivity. SQ exhibits a cellular action distinct from current antimalarials, acting early on malaria parasite's intraerythrocytic life cycle including merozoite invasion. The compound is a fast-acting parasitocidal agent and also exhibits curative property in the rodent malaria model when administered orally. In this report, we describe the synthesis, preliminary structure-function analysis, and the parasite developmental stage specific action of the SQ scaffold.


Asunto(s)
Aminoquinolinas/farmacología , Antimaláricos/farmacología , Descubrimiento de Drogas , Plasmodium falciparum/efectos de los fármacos , Estirenos/farmacología , Administración Oral , Aminoquinolinas/química , Aminoquinolinas/uso terapéutico , Animales , Antimaláricos/química , Antimaláricos/uso terapéutico , Eritrocitos/parasitología , Estadios del Ciclo de Vida/efectos de los fármacos , Malaria/tratamiento farmacológico , Malaria/parasitología , Merozoítos/efectos de los fármacos , Pruebas de Sensibilidad Parasitaria , Plasmodium berghei , Plasmodium falciparum/crecimiento & desarrollo , Ratas , Estirenos/química , Estirenos/uso terapéutico
18.
Int J Parasitol Drugs Drug Resist ; 6(1): 85-92, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27054067

RESUMEN

We screened a collection of synthetic compounds consisting of natural-product-like substructural motifs to identify a spirocyclic chromane as a novel antiplasmodial pharmacophore using an unbiased cell-based assay. The most active spirocyclic compound UCF 201 exhibits a 50% effective concentration (EC50) of 350 nM against the chloroquine-resistant Dd2 strain and a selectivity over 50 using human liver HepG2 cells. Our analyses of physicochemical properties of UCF 201 showed that it is in compliance with Lipinski's parameters and has an acceptable physicochemical profile. We have performed a limited structure-activity-relationship study with commercially available chromanes preserving the spirocyclic motif. Our evaluation of stage specificities of UCF 201 indicated that the compound is early-acting in blocking parasite development at ring, trophozoite and schizont stages of development as well as merozoite invasion. SPC is an attractive lead candidate scaffold because of its ability to act on all stages of parasite's aexual life cycle unlike current antimalarials.


Asunto(s)
Antimaláricos/química , Antimaláricos/farmacología , Benzofuranos/farmacología , Eritrocitos/parasitología , Malaria/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Compuestos de Espiro/farmacología , Animales , Antimaláricos/síntesis química , Antimaláricos/aislamiento & purificación , Benzofuranos/uso terapéutico , Evaluación Preclínica de Medicamentos , Estadios del Ciclo de Vida/efectos de los fármacos , Malaria/parasitología , Merozoítos/efectos de los fármacos , Merozoítos/crecimiento & desarrollo , Ratones Endogámicos BALB C , Plasmodium berghei , Plasmodium falciparum/crecimiento & desarrollo , Esquizontes/efectos de los fármacos , Esquizontes/crecimiento & desarrollo , Compuestos de Espiro/uso terapéutico , Relación Estructura-Actividad , Trofozoítos/efectos de los fármacos , Trofozoítos/crecimiento & desarrollo
19.
J Med Chem ; 57(17): 7425-34, 2014 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-25137549

RESUMEN

New antimalarial agents that exhibit multistage activities against drug-resistant strains of malaria parasites represent good starting points for developing next-generation antimalarial therapies. To facilitate the progression of such agents into the development phase, we developed an image-based parasitological screening method for defining drug effects on different asexual life cycle stages of Plasmodium falciparum. High-throughput screening of a newly assembled diversity-oriented synthetic library using this approach led to the identification of carbohybrid-based 2-aminopyrimidine compounds with fast-acting growth inhibitory activities against three laboratory strains of multidrug-resistant P. falciparum. Our structure-activity relationship study led to the identification of two derivatives (8aA and 11aA) as the most promising antimalarial candidates (mean EC50 of 0.130 and 0.096 µM against all three P. falciparum strains, selectivity indices >600, microsomal stabilities >80%, and mouse malaria ED50 values of 0.32 and 0.12 mg/kg/day, respectively), targeting all major blood stages of multidrug-resistant P. falciparum parasites.


Asunto(s)
Antimaláricos/farmacología , Estadios del Ciclo de Vida/efectos de los fármacos , Plasmodium falciparum/efectos de los fármacos , Pirimidinas/farmacología , Animales , Antimaláricos/química , Antimaláricos/farmacocinética , Área Bajo la Curva , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos , Células Hep G2 , Interacciones Huésped-Parásitos/efectos de los fármacos , Humanos , Malaria/parasitología , Malaria/prevención & control , Masculino , Tasa de Depuración Metabólica , Ratones , Ratones Endogámicos BALB C , Modelos Químicos , Estructura Molecular , Plasmodium chabaudi/efectos de los fármacos , Plasmodium chabaudi/fisiología , Plasmodium falciparum/crecimiento & desarrollo , Pirimidinas/química , Pirimidinas/farmacocinética , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad
20.
Biomed Res Int ; 2014: 835013, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24877138

RESUMEN

Nefang, a polyherbal product composed of Mangifera indica (bark and leaf), Psidium guajava, Carica papaya, Cymbopogon citratus, Citrus sinensis, and Ocimum gratissimum (leaves), is a potential therapy against P. falciparum malaria. In vitro antiplasmodial activities of its constituent solvent extracts were analyzed on CQ-sensitive (3D7) and multidrug resistant (Dd2) P. falciparum strains. The interactions involving the differential solvent extracts were further analyzed using a variable potency ratio drug combination approach. Effective concentration 50 (EC50) values were determined by nonlinear regression curve-fitting of the dose-response data and used in calculating the fractional inhibitory concentration 50 (FIC50) and combination indices (CI) for each pair. The derived EC50 values (3D7/Dd2, µ g/mL) are Nefang-96.96/55.08, MiB-65.33/34.58, MiL-82.56/40.04, Pg-47.02/25.79, Cp-1188/317.5, Cc-723.3/141, Cs-184.4/105.1, and Og-778.5/118.9. Synergism was obtained with MiB/Pg (CI = 0.351), MiL/Pg (0.358), MiB/Cs (0.366), MiL/Cs (0.482), Pg/Cs (0.483), and Cs/Og (0.414) when analyzed at equipotency ratios. Cytotoxicity testing of Nefang and the solvent extracts on two human cell lines (Hep G2 and U2OS) revealed no significant toxicity relative to their antiplasmodial activities (SI > 20). Taken together, our data confirm the antimalarial activities of Nefang and its constituent plant extracts and identified extract pairs with promising synergistic interactions for exploitation towards a rational phytotherapeutic and evidence-based antimalarial drug discovery.


Asunto(s)
Antimaláricos , Malaria Falciparum/tratamiento farmacológico , Extractos Vegetales , Plasmodium falciparum , Solventes/química , Antimaláricos/química , Antimaláricos/farmacología , Evaluación Preclínica de Medicamentos , Células Hep G2 , Humanos , Extractos Vegetales/química , Extractos Vegetales/farmacología
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