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1.
BMC Med Imaging ; 24(1): 11, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172764

RESUMEN

BACKGROUND: To validate the feasibility of water enema PET/CT (WE-PET/CT) in incidental colorectal 18F-FDG uptake and improve the accuracy of diagnosing colorectal neoplastic lesions. METHODS: We retrospectively analysed the electronic records of 338 patients undergoing common PET/CT and WE-PET/CT at our hospital. PET/CT results were correlated with colonoscopy pathology and follow-up results. The ROC contrast curve was plotted to evaluate the accuracy of SUVmax on common PET/CT and WE-PET/CT for detecting neoplastic lesions. SUVmax and the median retention indexes (RIs) of cancerous, precancerous, and benign lesions and physiologic uptake were compared. RESULTS: The sensitivity, specificity and accuracy of diagnosing neoplastic lesions with common PET/CT were 84.0%, 78.3% and 80.2%, respectively. The corresponding results with WE-PET/CT were 95.8%, 96.5% and 96.2%. The AUC of SUVmax on WE-PET/CT was significantly higher than that on common PET/CT (0.935 vs. 0.524, p < 0.001). The median SUVmax on WE-PET/CT was significantly higher than that on common PET/CT in cancerous and precancerous lesions, and significantly decreased in benign lesions and physiologic uptake (p < 0.001). The RI was significantly different between cancerous lesions and physiologic uptake, between precancerous lesions and physiologic uptake, between benign lesions and physiologic uptake, and between cancerous and benign lesions (p < 0.05). CONCLUSIONS: WE-PET/CT is a noninvasive, well-tolerated and effective technique for diagnosing incidental colorectal 18F-FDG uptake. It is helpful for a timely colonoscopy and can effectively avoid an unnecessary colonoscopy for incidental colorectal 18F-FDG uptake.


Asunto(s)
Neoplasias Colorrectales , Lesiones Precancerosas , Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Fluorodesoxiglucosa F18 , Agua , Estudios Retrospectivos , Tomografía de Emisión de Positrones , Radiofármacos , Hallazgos Incidentales , Neoplasias Colorrectales/diagnóstico , Enema
2.
Genomics Proteomics Bioinformatics ; 21(5): 1066-1079, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37898309

RESUMEN

The Resource for Coronavirus 2019 (RCoV19) is an open-access information resource dedicated to providing valuable data on the genomes, mutations, and variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this updated implementation of RCoV19, we have made significant improvements and advancements over the previous version. Firstly, we have implemented a highly refined genome data curation model. This model now features an automated integration pipeline and optimized curation rules, enabling efficient daily updates of data in RCoV19. Secondly, we have developed a global and regional lineage evolution monitoring platform, alongside an outbreak risk pre-warning system. These additions provide a comprehensive understanding of SARS-CoV-2 evolution and transmission patterns, enabling better preparedness and response strategies. Thirdly, we have developed a powerful interactive mutation spectrum comparison module. This module allows users to compare and analyze mutation patterns, assisting in the detection of potential new lineages. Furthermore, we have incorporated a comprehensive knowledgebase on mutation effects. This knowledgebase serves as a valuable resource for retrieving information on the functional implications of specific mutations. In summary, RCoV19 serves as a vital scientific resource, providing access to valuable data, relevant information, and technical support in the global fight against COVID-19. The complete contents of RCoV19 are available to the public at https://ngdc.cncb.ac.cn/ncov/.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/genética , Bases del Conocimiento , Mutación
3.
J Transl Med ; 21(1): 399, 2023 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-37337244

RESUMEN

BACKGROUND: Bone marrow metastasis (BMM) is underestimated in gastric cancer (GC). GC with BMM frequently complicate critical hematological abnormalities like diffused intravascular coagulation and microangiopathic hemolytic anemia, which constitute a highly aggressive GC (HAGC) subtype. HAGC present a very poor prognosis with peculiar clinical and pathological features when compared with not otherwise specified advanced GC (NAGC). But the molecular mechanisms underlying BMM from GC remain rudimentary. METHODS: The transcriptomic difference between HAGC and NAGC were analyzed. Genes that were specifically upregulated in HAGC were identified, and their effect on cell migration and invasion was studied. The function of ACTN2 gene were confirmed by GC cell lines, bone-metastatic animal model and patients' tissues. Furthermore, the molecular mechanism of ACTN2 derived-BMM was explored by multiple immunofluorescence staining, western blot, chromatin immunoprecipitation, and luciferase reporter assays. RESULTS: We elucidated the key mechanisms of BMM depending on the transcriptomic difference between HAGC and NAGC. Five genes specifically upregulated in HAGC were assessed their effect on cell migration and invasion. The ACTN2 gene encoding protein α-Actinin-2 was detected enhanced the metastatic capability and induced BMM of GC cells in mouse models. Mechanically, α-Actinin-2 was involved in filopodia formation where it promoted the Actin filament cross-linking by replacing α-Actinin-1 to form α-Actinin-2:α-Actinin-4 complexes in GC cells. Moreover, NF-κB subunit RelA and α-Actinin-2 formed heterotrimers in the nuclei of GC cells. As a direct target of RelA:α-Actinin-2 heterotrimers, the ACTN2 gene was a positive auto-regulatory loop for α-Actinin-2 expression. CONCLUSIONS: We demonstrated a link between filopodia, BMM and ACTN2 activation, where a feedforward activation loop between ACTN2 and RelA is established via actin in response to distant metastasis. Given the novel filopodia formation function and the new mechanism of BMM in GC, we propose ACTN2 as a druggable molecular vulnerability that may provide potential therapeutic benefit against BMM of GC.


Asunto(s)
Actinina , Neoplasias de la Médula Ósea , Neoplasias Gástricas , Animales , Ratones , Actinina/genética , Actinina/metabolismo , Línea Celular Tumoral , FN-kappa B/metabolismo , Seudópodos/metabolismo , Seudópodos/patología , Neoplasias Gástricas/patología
4.
Front Oncol ; 13: 1106890, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36910656

RESUMEN

Occult breast cancer is an uncommon type of breast cancer and its diagnosis is challenging. It is usually invisible on multiple imaging examines. Metastases to the rectum and inguinal lymph nodes from occult breast lobular cancer are even rarer. 68Ga-DOTA peptides can image neuroendocrine tumors by targeting specific somatostatin receptors. Besides, other tumors, including breast cancer, have been shown to express somatostatin receptors. In this case, we presented a 63-year-old woman who underwent both 18F-FDG and 68Ga-DOTATATE PET/CT due to a rectal polyp. An endoscopic excision biopsy confirmed metastatic carcinoma of suspected breast origin, but subsequent ultrasound and MRI showed no signs of malignancy in the breast and adnexa uteri. PET/CT showed obvious 68Ga-DOTATATE activity in bilateral axillary and right inguinal lymph nodes with mild 18F-FDG uptake. Final histopathology at the left axillary, right inguinal lymph nodes, and rectum indicated metastases from breast cancer while the origin remained radiologically occult. Additionally, one uterine fibroids was found with positive uptake of 68Ga-DOTATATE and negative uptake of 18F-FDG. This case suggested that 68Ga-DOTATAE PET/CT may be an effective supplement in diagnosing OBC lymph node metastases with mild 18F-FDG uptake, and it may provide a new technology for the clinical diagnosis of occult breast cancer.

5.
Nucleic Acids Res ; 51(D1): D969-D976, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36263826

RESUMEN

GWAS Atlas (https://ngdc.cncb.ac.cn/gwas/) is a manually curated resource of genome-wide genotype-to-phenotype associations for a wide range of species. Here, we present an updated implementation of GWAS Atlas by curating and incorporating more high-quality associations, with significant improvements and advances over the previous version. Specifically, the current release of GWAS Atlas incorporates a total of 278,109 curated genotype-to-phenotype associations for 1,444 different traits across 15 species (10 plants and 5 animals) from 830 publications and 3,432 studies. A collection of 6,084 lead SNPs of 439 traits and 486 experiment-validated causal variants of 157 traits are newly added. Moreover, 1,056 trait ontology terms are newly defined, resulting in 1,172 and 431 terms for Plant Phenotype and Trait Ontology and Animal Phenotype and Trait Ontology, respectively. Additionally, it is equipped with four online analysis tools and a submission platform, allowing users to perform data analysis and data submission. Collectively, as a core resource in the National Genomics Data Center, GWAS Atlas provides valuable genotype-to-phenotype associations for a diversity of species and thus plays an important role in agronomic trait study and molecular breeding.


Asunto(s)
Estudio de Asociación del Genoma Completo , Plantas , Animales , Estudios de Asociación Genética , Estudio de Asociación del Genoma Completo/métodos , Genómica/métodos , Bases del Conocimiento , Fenotipo , Polimorfismo de Nucleótido Simple , Plantas/genética , Atlas como Asunto
6.
Nucleic Acids Res ; 51(D1): D853-D860, 2023 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-36161321

RESUMEN

Single-cell studies have delineated cellular diversity and uncovered increasing numbers of previously uncharacterized cell types in complex tissues. Thus, synthesizing growing knowledge of cellular characteristics is critical for dissecting cellular heterogeneity, developmental processes and tumorigenesis at single-cell resolution. Here, we present Cell Taxonomy (https://ngdc.cncb.ac.cn/celltaxonomy), a comprehensive and curated repository of cell types and associated cell markers encompassing a wide range of species, tissues and conditions. Combined with literature curation and data integration, the current version of Cell Taxonomy establishes a well-structured taxonomy for 3,143 cell types and houses a comprehensive collection of 26,613 associated cell markers in 257 conditions and 387 tissues across 34 species. Based on 4,299 publications and single-cell transcriptomic profiles of ∼3.5 million cells, Cell Taxonomy features multifaceted characterization for cell types and cell markers, involving quality assessment of cell markers and cell clusters, cross-species comparison, cell composition of tissues and cellular similarity based on markers. Taken together, Cell Taxonomy represents a fundamentally useful reference to systematically and accurately characterize cell types and thus lays an important foundation for deeply understanding and exploring cellular biology in diverse species.

7.
Nucleic Acids Res ; 50(D1): D1131-D1138, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34718720

RESUMEN

Brain is the central organ of the nervous system and any brain disease can seriously affect human health. Here we present BrainBase (https://ngdc.cncb.ac.cn/brainbase), a curated knowledgebase for brain diseases that aims to provide a whole picture of brain diseases and associated genes. Specifically, based on manual curation of 2768 published articles along with information retrieval from several public databases, BrainBase features comprehensive collection of 7175 disease-gene associations spanning a total of 123 brain diseases and linking with 5662 genes, 16 591 drug-target interactions covering 2118 drugs/chemicals and 623 genes, and five types of specific genes in light of expression specificity in brain tissue/regions/cerebrospinal fluid/cells. In addition, considering the severity of glioma among brain tumors, the current version of BrainBase incorporates 21 multi-omics datasets, presents molecular profiles across various samples/conditions and identifies four groups of glioma featured genes with potential clinical significance. Collectively, BrainBase integrates not only valuable curated disease-gene associations and drug-target interactions but also molecular profiles through multi-omics data analysis, accordingly bearing great promise to serve as a valuable knowledgebase for brain diseases.


Asunto(s)
Encefalopatías/genética , Biología Computacional , Bases de Datos Genéticas , Encefalopatías/clasificación , Glioma/genética , Glioma/patología , Humanos , Bases del Conocimiento
9.
Cell Death Dis ; 12(8): 731, 2021 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-34301921

RESUMEN

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. SET and MYND domain-containing protein 3 (SMYD3) has been shown to promote the progression of various types of human cancers, including liver cancer; however, the detailed molecular mechanism is still largely unknown. Here, we report that SMYD3 expression in HCC is an independent prognostic factor for survival and promotes the proliferation and migration of HCC cells. We observed that SMYD3 upregulated sphingosine-1-phosphate receptor 1 (S1PR1) promoter activity by methylating histone 3 (H3K4me3). S1PR1 was expressed at high levels in HCC samples, and high S1PR1 expression was associated with shorter survival. S1PR1 expression was also positively correlated with SMYD3 expression in HCC samples. We confirmed that SMYD3 promotes HCC cell growth and migration in vitro and in vivo by upregulating S1PR1 expression. Further investigations revealed that SMYD3 affects critical signaling pathways associated with the progression of HCC through S1PR1. These findings strongly suggest that SMYD3 has a crucial function in HCC progression that is partially mediated by histone methylation at the downstream gene S1PR1, which affects key signaling pathways associated with carcinogenesis and the progression of HCC.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Progresión de la Enfermedad , N-Metiltransferasa de Histona-Lisina/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Regiones Promotoras Genéticas , Receptores de Esfingosina-1-Fosfato/genética , Apoptosis/genética , Secuencia de Bases , Carcinoma Hepatocelular/genética , Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Células HEK293 , N-Metiltransferasa de Histona-Lisina/genética , Histonas/metabolismo , Humanos , Neoplasias Hepáticas/genética , Lisina/metabolismo , Metilación , Invasividad Neoplásica , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transducción de Señal , Receptores de Esfingosina-1-Fosfato/metabolismo , Ensayo de Tumor de Célula Madre
10.
Chemosphere ; 275: 130093, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33652274

RESUMEN

The objective of this present study was to understand the distribution patterns of various forms of soil phosphorus (P) and the biotic and abiotic factors affecting the soil P fractions under long-term cover crops. Here, we investigated the characteristics of soil P forms, community structure of P-solubilizing bacteria (using 16S rRNA) and the related enzyme activity under clean tillage (CT), 14 years of white clover (WC, Trifolium repens L.) and orchard grass (OG, Dactylis glomerata L.) cover crops in a rain-fed apple orchard on the Weibei Loess Plateau, China. Relative to CT treatment, long-term cover crops enhanced the bioavailability of soil P by increasing the contents of total phosphorus (TP), microbial phosphorus (MBP), organic phosphorus (Po) and certain forms of inorganic phosphorus (e.g. Al-P, Ca2-P, Ca8-P and Fe-P) in the surface soil, in addition, WC treatment also increase the available P (AP) contents in the topsoil. A redundant analysis (RDA) showed that soil organic matter (SOM), NH4+-N and pH were the key environmental factors affecting the morphological changes of soil P. In addition, the effects of long-term cover crops on soil P forms were mainly concentrated in the topsoil, and the WC treatment had a greater impact on soil P composition than the OG treatment. Interestingly, long-term cover crops effectively increased the abundances of P-solubilizing bacteria, such as Streptomyces, Sphingomonas, Nocardioides and Haliangium, and enhanced the alkaline phosphatase (ALP) activity. Overall, long-term cover crops were an effective strategy to activate soil P as they improve the soil environment.


Asunto(s)
Malus , Suelo , China , Fósforo , ARN Ribosómico 16S , Lluvia , Microbiología del Suelo
11.
BMC Med Imaging ; 20(1): 91, 2020 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32746794

RESUMEN

BACKGROUND: Secondary hyperparathyroidism (SHPT) usually requires parathyroidectomy when drug regimens fail. However, obtaining an exact preoperative map of the locations of the parathyroid glands is a challenge. The purpose of this study was to compare the diagnostic performance of US, dual-phase 99mTc-MIBI scintigraphy, early and delayed 99mTc-MIBI SPECT/CT in patients with SHPT. METHODS: Sixty patients with SHPT who were undergoing dialysis were evaluated preoperatively by US, dual-phase 99mTc-MIBI scintigraphy, early and delayed 99mTc-MIBI SPECT/CT. Postoperative pathology served as the gold standard. The sensitivity, specificity, and accuracy were determined for each method. Spearman correlation analysis was used to analyse the correlation of hyperplastic parathyroid calcification with serum alkaline phosphatase (ALP) and parathyroid hormone (PTH). RESULTS: A total of 229 lesions in 60 patients were pathologically confirmed to be parathyroid hyperplasia, with 209 lesions in typical sites, 15 lesions in the upper mediastinum and 5 lesions in the thyroid. A total of 88.33% (53/60) of patients had four lesions. US, early and delayed 99mTc-MIBI SPECT/CT had significantly higher sensitivity and accuracy than dual-phase 99mTc-MIBI scintigraphy (P < 0.001). Furthermore, early 99mTc-MIBI SPECT/CT had significantly higher sensitivity (P < 0.001) and accuracy (P = 0.001 and P < 0.001) than US and delayed 99mTc-MIBI SPECT/CT. In patients with ectopic hyperplastic parathyroid glands, the sensitivity of early 99mTc-MIBI SPECT/CT (90%) was significantly higher than that of US (55%) and dual-phase 99mTc-MIBI scintigraphy (50%) (P < 0.05). The Spearman correlation results showed a significant albeit weak association between calcification and both serum PTH and ALP (P = 0.002). CONCLUSION: The ability of early 99mTc-MIBI SPECT/CT to detect hyperplastic parathyroid glands in patients with SHPT is superior to that of US, dual-phase 99mTc-MIBI scintigraphy and delayed 99mTc-MIBI SPECT/CT; furthermore, dual-phase 99mTc-MIBI SPECT/CT is not essential.


Asunto(s)
Hiperparatiroidismo Secundario/diagnóstico por imagen , Glándulas Paratiroides/diagnóstico por imagen , Radiofármacos/administración & dosificación , Insuficiencia Renal Crónica/terapia , Tecnecio Tc 99m Sestamibi/administración & dosificación , Adulto , Fosfatasa Alcalina/sangre , Femenino , Humanos , Hiperparatiroidismo Secundario/sangre , Hiperparatiroidismo Secundario/cirugía , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Glándulas Paratiroides/patología , Glándulas Paratiroides/cirugía , Hormona Paratiroidea/sangre , Periodo Preoperatorio , Diálisis Renal , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/complicaciones , Sensibilidad y Especificidad , Tomografía Computarizada por Tomografía Computarizada de Emisión de Fotón Único , Factores de Tiempo , Ultrasonografía
12.
RSC Adv ; 10(39): 23276-23285, 2020 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35520297

RESUMEN

This work investigated the optimization of the 68Ga radiolabeling of the dendritic polylysine-1,4,7-triazacyclononane-1,4,7-triacetic acid conjugate (DGL-NOTA). Under pH = 4.0, reaction temperature of 70 °C, and incubation time of 10.0 min, the conjugate (DGL-NOTA) radiochemical yield was between 50% and 70%. After separation and purification, the radiochemical purity was greater than 98%. The radiolabeled formulation (68Ga-NOTA-DGL-PEG-RGDyC) remained stable in both phosphate buffer and serum (all radiochemically greater than 95%) for up to 2 hours with a specific activity of 30 GBq/µmol. Cellular experimental studies have shown that radiolabeled preparations can rapidly enter U87MG cells, and after 2 hours, there was still retention of imaging agents in the cells. In vivo distribution studies had shown that the tracer is excreted by the kidneys. Two hours after injecting the imaging agent, the U87MG tumor tissue uptake value was (4.67 ± 0.09)% ID/g. Positron emission tomography (PET) imaging in animals showed that 68Ga-NOTA-DGL-PEG-RGDyC had good targeting and can be enriched in tumor sites. Through hemolysis testing and morphological changes of red blood cells, it was proved that NOTA-DGL-PEG-RGDyC has good blood compatibility.

13.
J Environ Manage ; 250: 109531, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31513995

RESUMEN

Dissolved organic matter (DOM) is an important parameter that reflects soil fertility and quality. In this study, the effects of intercropping perennial ryegrass and straw mulch on the content, composition and spectral characteristics of soil DOM in orchards in arid and semi-arid areas were investigated by three-dimensional fluorescence excitation-emission matrix (EEM) combined with parallel factor analysis (PARAFAC). Three treatments were applied in a 6-year-old apple orchard on the Loess Plateau: (1) clean tillage (CT); (2) intercropping perennial ryegrass mulch (RE); (3) intercropping straw mulch (CS). Soil samples (0-10, 10-20, 20-40, 40-60, 60-80, 80-100 cm) were collected from different treatments. The total soil organic carbon (SOC) and dissolved organic carbon (DOC) content were ranked as CS> RE> CT, and decreased with soil depth. In addition, the vertical distribution of DOC with different soil depth was caused by organic matter input but not leaching. Three humic-like components and two protein-like components were identified by EEM-PARAFAC. Fluorescence spectra showed that humic-like compounds were the dominant fractions in soil DOM in the CS treatment. Fluorescence Index (FI) indicated that the proportion of plant residues and soil organic matter derived DOM ranked as CT> RE> CS and gradually decreased with soil depth. Our results highlight the key role of orchard intercropping mulch in improving the content and compositions of soil DOM through different forms of organic inputs and provide new theoretical support for the evaluation of soil fertility in orchards.


Asunto(s)
Malus , Suelo , Carbono , Sustancias Húmicas , Espectrometría de Fluorescencia
14.
Bioengineered ; 10(1): 207-217, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31169443

RESUMEN

Groundcover management can significantly affect soil microbial metabolic activities, especially carbon metabolism, in apple orchards. However, there have been few studies on the effects of groundcover on the seasonality of soil microbial carbon metabolism. We, therefore, studied soil microbial carbon metabolism in an apple orchard on China's Loess Plateau under four single species cover crops (the grass Dactylis glomerata L., and the legumes Trifolium repens, Coronilla varia L., Lotus corniculatus L.) during spring, summer and fall. Cover cropping significantly, but differentially, promoted soil microbial carbon metabolism in spring and fall. However, cover cropping leads to a significant reduction of soil moisture in spring and summer due to the competition of soil moisture between the cover crops and apple trees, which probably lead to the changes in types of carbon substances metabolizing by soil microbes in summer. Besides, cover crop significantly enhanced soil organic carbon contents between three seasons while clean cultivation had slight, non-significant effects. The promotion of soil microbial metabolic activities was probably an important mechanism for the carbon accumulation, and we postulate that leguminous cover plants may have significantly different effects, mediated through their root exudates, from grasses on soil carbon contents.


Asunto(s)
Carbono/metabolismo , Malus , Microbiología del Suelo , Estaciones del Año , Suelo
15.
Bioengineered ; 10(1): 218-228, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31138017

RESUMEN

Intercropping can introduce greater plant diversity and functional complementarity in an arable crop system but inter- and intracompetition can between intercropped crops. The rhizo-box was established of apple-white clover intercropped system to examine the competitive relationship between intercropped crops on the Loess Plateau. The results showed that the competitive relationship between intercropped crops was dynamic and changed with the crop competitiveness. Crop competitiveness was characterized by root development, although intercropping inhibited the development and nutrient accumulation aboveground of apple trunks and branches, intercropped apples still maintained a larger root system than under monoculture and the root morphology of intercropped apples changed significantly. White clover had lower competitiveness than apple at the beginning of the year, which was reflected in the inhibited development in May. However in July and October, intercropped white clover had more biomass and nutrient accumulation than under monoculture.


Asunto(s)
Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/metabolismo , Malus/crecimiento & desarrollo , Malus/metabolismo , Biomasa , Medicago/crecimiento & desarrollo , Medicago/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo
16.
Arch Pharm Res ; 29(6): 514-9, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16833021

RESUMEN

A simple HPLC method using UV detection was developed and validated for the determination of levodropropizine (LDP) in dog plasma. The sample was prepared for injection using a liquid-liquid extraction method with 1-phenypiperazine as the internal standard. The mobile phase was methanol-diethylamine solution (0.05 M) (20:80, v/v, pH adjusted to 3.0 with H3PO4) with a detection wavelength of 240 nm. The limit of quantitation (LOQ) of LDP in a biological matrix was determined to be 25.25 ng/mL. The calibration curve was linear across the concentration range of 25.25 to 2020 ng/mL. The intra-day and inter-day precision values (CV %) were within 7% and accuracy (R.E. %) was within 6% of the nominal values for medium (252.5 ng/mL) and high (2020 ng/mL) LDP concentrations. For the LDP concentration at the LOQ, the intra-day and inter-day precision and accuracy were within 20% and 10%, respectively. The average absolute recovery for LDP was 70.28%. This method was successfully used to analyze plasma samples in a steady-state bioavailability study of a newly developed sustained-release LDP tablets (SR) using immediate-release tablets (IR) as the reference. The relative bioavailability of the SR was determined to be 106.3 +/- 12.8% (n=6). The Cmax of the SR was significantly lower (P<0.05), and the tmax was significantly longer than that of the IR (P<0.05). The results of ANOVA and two one-sided tests indicated that the SR exhibited acceptable sustained release properties and was bioequivalent to the IR.


Asunto(s)
Antitusígenos/farmacocinética , Cromatografía Líquida de Alta Presión/métodos , Glicoles de Propileno/farmacocinética , Animales , Antitusígenos/sangre , Disponibilidad Biológica , Preparaciones de Acción Retardada , Perros , Glicoles de Propileno/sangre , Reproducibilidad de los Resultados , Espectrofotometría Ultravioleta , Comprimidos
17.
Life Sci ; 72(25): 2895-904, 2003 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-12697272

RESUMEN

We investigated the rat submaxillary gland for the presence of GnRH and GnRH receptors, the localization and colocalization of GnRH, GnRH receptor and their mRNA, and studied the sequence of GnRH receptor complementary DNA (cDNA) by immunohistochemistry, in situ hybridization and RT-PCR. The results showed that GnRH and GnRH receptor immunoreactive materials were colocalized in the epithelial cells of the serous acinus and glandular duct. The GnRH and GnRH receptor mRNA hybridization signals were detected in the above cells. The sequence obtained from the RT-PCR product was identical to the published cDNA sequence of GnRH receptor in the rat pituitary. The results suggested that the rat submaxillary gland was capable of synthesizing GnRH and GnRH receptors. GnRH may be involved in the functional regulation of the submaxillary gland through autocrine or paracrine activity.


Asunto(s)
Hormona Liberadora de Gonadotropina/sangre , Receptores LHRH/metabolismo , Glándula Submandibular/metabolismo , Animales , Secuencia de Bases , ADN Complementario/biosíntesis , ADN Complementario/genética , Células Epiteliales/metabolismo , Hormona Liberadora de Gonadotropina/biosíntesis , Hormona Liberadora de Gonadotropina/genética , Inmunohistoquímica , Hibridación in Situ , Masculino , Datos de Secuencia Molecular , ARN Mensajero/biosíntesis , Ratas , Ratas Sprague-Dawley , Receptores LHRH/biosíntesis , Receptores LHRH/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Glándula Submandibular/anatomía & histología
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