Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Addict Biol ; 26(1): e12862, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-31997525

RESUMEN

Methamphetamine (METH) enhances dopamine (DA) transmission in the mesolimbic system implicated in its reinforcing effects. Our previous studies have shown that acupuncture attenuates drug-seeking behaviors by modulating GABAergic transmission in the ventral tegmental area and DA release in the nucleus accumbens (NAc) of the striatum. The effects of acupuncture on METH-induced behaviors and its mediation by neural pathways remain a relatively understudied area of research. The central amygdala (CeA) plays a critical role in physiological and behavioral responses to somatosensory and drug stimuli and has been implicated in negative reinforcement. Thus, we evaluated the role of the CeA in acupuncture effects on locomotor activity, positive affective states, and DA release in the NAc following acute administration of METH. Acupuncture at acupoint HT7 reduced locomotor activity, 50-kHz ultrasonic vocalizations (USVs), and NAc DA release following systemic injection of METH, which was prevented by electrolytic lesions or optogenetic inhibition of the CeA. Acupuncture alone excited CeA neurons and reversed the suppression of CeA neurons induced by METH. These results suggest that acupuncture can relieve psychomotor responses and positive affective states following METH by inhibiting NAc DA release and this effect is mediated by activation of CeA neurons.


Asunto(s)
Terapia por Acupuntura , Núcleo Amigdalino Central/metabolismo , Comportamiento de Búsqueda de Drogas/fisiología , Metanfetamina/metabolismo , Animales , Estimulantes del Sistema Nervioso Central/metabolismo , Dopamina/metabolismo , Locomoción , Masculino , Neuronas/metabolismo , Núcleo Accumbens/metabolismo , Ratas , Ratas Sprague-Dawley , Refuerzo en Psicología , Área Tegmental Ventral/metabolismo
2.
Virol J ; 17(1): 94, 2020 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-32631440

RESUMEN

BACKGROUND: The emergence of influenza viruses resistant to anti-influenza drugs is a threat to global public health. The Korea Centers for Disease Control and Prevention operates the Korea Influenza and Respiratory Viruses Surveillance System (KINRESS) to monitor epidemics of influenza and Severe Acute Respiratory Infection (SARI) to identify mutated influenza viruses affecting drug resistance, pathogenesis, and transmission. METHODS: Oropharyngeal swab samples were collected from KINRESS and SARI during the 2018-2019 season. The specimens confirmed influenza virus using real-time RT-PCR on inoculated MDCK cells. HA and NA sequences of the influenza viruses were analyzed for phylogeny and mutations. Neuraminidase inhibition and hemagglutination inhibition assays were utilized to characterize the isolates. RESULTS: Two A(H1N1)pdm09 isolates harboring an H275Y substitution in the neuraminidase sequence were detected in patients with acute hematologic cancer. They had prolonged respiratory symptoms, with the virus present in the respiratory tract despite oseltamivir and peramivir treatment. Through the neuraminidase inhibition assay, both viruses were found to be resistant to oseltamivir and peramivir, but not to zanamivir. Although hemagglutinin and neuraminidase phylogenetic analyses suggested that the 2 A(H1N1)pdm09 isolates were not identical, their antigenicity was similar to that of the 2018-19 influenza vaccine virus. CONCLUSIONS: Our data indicate the utility of monitoring influenza-infected immunocompromised patients in general hospitals for the early detection of emerging neuraminidase inhibitor-resistant viruses and maintaining continuous laboratory surveillance of patients with influenza-like illness in sentinel clinics to monitor the spread of such new variants. Finally, characterization of the virus can inform the risk assessment for future epidemics and pandemics caused by drug-resistant influenza viruses.


Asunto(s)
Farmacorresistencia Viral/genética , Inhibidores Enzimáticos/farmacología , Huésped Inmunocomprometido , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Subtipo H1N1 del Virus de la Influenza A/genética , Neuraminidasa/antagonistas & inhibidores , Ácidos Carbocíclicos/farmacología , Adulto , Sustitución de Aminoácidos , Antivirales/farmacología , Femenino , Guanidinas/farmacología , Humanos , Gripe Humana , Mutación , Orofaringe/virología , Oseltamivir/farmacología , Filogenia , República de Corea , Análisis de Secuencia de ADN , Zanamivir/farmacología
3.
Environ Sci Technol ; 54(16): 9949-9957, 2020 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-32660243

RESUMEN

Biological concentrations of methylmercury (MeHg) are elevated throughout the Arctic Ocean; however, to date, the major sources and the spatial variability of MeHg are not well quantified. To identify the major inputs and outputs of MeHg to the Arctic shelf water column, we measured MeHg concentrations in the seawater and sediment samples from the East Siberian Sea collected from August to September 2018. We found that the MeHg concentrations in seawater and pore water were higher on the slope than on the shelf, while the MeHg concentrations in the sediment were higher on the shelf than on the slope. We created a mass budget for MeHg and found that the benthic diffusion and resuspension largely exceed other sources, such as atmospheric deposition and river water input. The major sinks of MeHg in the water column were dark demethylation and evasion. When we extrapolated our findings on benthic diffusion to the entire Arctic shelf system, the annual MeHg diffusion from the shelf sediments was estimated to be 23,065 ± 939 mol yr-1, about 2 times higher than previously proposed river discharges. Our study suggests that the MeHg input from shelf sediments in the Arctic Ocean is significant and has been previously underestimated.


Asunto(s)
Mercurio , Compuestos de Metilmercurio , Contaminantes Químicos del Agua , Regiones Árticas , Monitoreo del Ambiente , Sedimentos Geológicos , Mercurio/análisis , Ríos , Agua de Mar , Contaminantes Químicos del Agua/análisis
4.
Molecules ; 25(1)2020 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-31906359

RESUMEN

Isoflavones in soybeans are well-known phytoestrogens. Soy isoflavones present in conjugated forms are converted to aglycone forms during processing and storage. Isoflavone aglycones (IFAs) of soybeans in human diets have poor solubility in water, resulting in low bioavailability and bioactivity. Enzyme-mediated glycosylation is an efficient and environmentally friendly way to modify the physicochemical properties of soy IFAs. In this study, we determined the optimal reaction conditions for Deinococcus geothermalis amylosucrase-mediated α-1,4 glycosylation of IFA-rich soybean extract to improve the bioaccessibility of IFAs. The conversion yields of soy IFAs were in decreasing order as follows: genistein > daidzein > glycitein. An enzyme quantity of 5 U and donor:acceptor ratios of 1000:1 (glycitein) and 400:1 (daidzein and genistein) resulted in high conversion yield (average 95.7%). These optimal reaction conditions for transglycosylation can be used to obtain transglycosylated IFA-rich functional ingredients from soybeans.


Asunto(s)
Deinococcus/enzimología , Glucosiltransferasas/metabolismo , Glycine max/química , Isoflavonas/química , Extractos Vegetales/química , beta-Glucanos/química , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Escherichia coli/genética , Vectores Genéticos , Genisteína/química , Glucosiltransferasas/genética , Glicosilación , Isoflavonas/biosíntesis , Isoflavonas/aislamiento & purificación , Isoflavonas/farmacocinética , Espectrometría de Masas , Fitoestrógenos/química , Extractos Vegetales/aislamiento & purificación , beta-Glucanos/farmacocinética
6.
Emerg Infect Dis ; 24(6): 1156-1158, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29774855

RESUMEN

Taenia saginata is the most common human tapeworm worldwide but has been unknown in Myanmar. In 2017, fecal examination in Yangon, Myanmar, revealed eggs of Taenia species in 2 children from a monastic school. Several proglottids expelled after medication with praziquantel were morphologically and molecularly confirmed to be T. saginata tapeworms.


Asunto(s)
Técnicas de Diagnóstico Molecular , Taenia saginata/genética , Teniasis/diagnóstico , Teniasis/parasitología , Animales , Niño , Heces/parasitología , Genes de Helminto , Humanos , Mianmar , Filogenia , Reacción en Cadena de la Polimerasa , Taenia saginata/clasificación
7.
Korean J Physiol Pharmacol ; 19(4): 365-72, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26170741

RESUMEN

Aripiprazole (ARI) is a commonly prescribed medication used to treat schizophrenia and bipolar disorder. To date, there have been no studies regarding the molecular pathological and immunotoxicological profiling of aripiprazole. Thus, in the present study, we prepared two different formulas of aripiprazole [Free base crystal of aripiprazole (ARPGCB) and cocrystal of aripiprazole (GCB3004)], and explored their effects on the patterns of survival and apoptosis-regulatory proteins under acute toxicity and cytotoxicity test conditions. Furthermore, we also evaluated the modulatory activity of the different formulations on the immunological responses in macrophages primed by various stimulators such as lipopolysaccharide (LPS), pam3CSK, and poly(I:C) via toll-like receptor 4 (TLR4), TLR2, and TLR3 pathways, respectively. In liver, both ARPGCB and GCB3004 produced similar toxicity profiles. In particular, these two formulas exhibited similar phospho-protein profiling of p65/nuclear factor (NF)-κB, c-Jun/activator protein (AP)-1, ERK, JNK, p38, caspase 3, and bcl-2 in brain. In contrast, the patterns of these phospho-proteins were variable in other tissues. Moreover, these two formulas did not exhibit any cytotoxicity in C6 glioma cells. Finally, the two formulations at available in vivo concentrations did not block nitric oxide (NO) production from activated macrophage-like RAW264.7 cells stimulated with LPS, pam3CSK, or poly(I:C), nor did they alter the morphological changes of the activated macrophages. Taken together, our present work, as a comparative study of two different formulas of aripiprazole, suggests that these two formulas can be used to achieve similar functional activation of brain proteins related to cell survival and apoptosis and immunotoxicological activities of macrophages.

8.
Neuropharmacology ; 205: 108917, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-34896117

RESUMEN

Prolintane (1-Phenyl-2-pyrrolidinylpentane), a synthetic central nervous system (CNS) stimulant, is structurally similar to amphetamine but pharmacologically acts as a dopamine reuptake inhibitor like cocaine. While several case studies reported adverse effects and recreational use of prolintane, the abuse potential of the drug has not been systemically examined yet. In the present study, we evaluated the behavioral effects of prolintane regarding its abuse liability in rodents using locomotor activity, conditioned place preference (CPP), self-administration (SA), and drug discrimination paradigms, as well as in-vivo microdialysis experiment. First, acute prolintane (10 and 20 mg/kg, intraperitoneal injection) increased locomotor activity (distance traveled, cm) in mice but to a lesser degree than methamphetamine (as a positive control). We also found that a single and solitary injection of prolintane (20 mg/kg, IP) significantly increased extracellular dopamine in the striatum. The following result suggests that its stimulatory effects might be associated with the mesolimbic dopaminergic pathway. Further, prolintane produced a significant drug-paired place preference at doses of both 10 and 20 mg/kg. In the SA experiment, the mice that self-administered prolintane intravenously (4 mg/kg/inf) showed a higher infusion and active lever responses but not inactive lever responses. Additionally, cumulative doses of prolintane partially elicited cocaine-appropriate lever responses (38.57% at doses up to 10 mg/kg) in rats. These results implied that prolintane has not only rewarding and reinforcing effects but also interoceptive stimulus properties, which are similar to cocaine at a moderate level. Taken together, this study was the first to show, to our knowledge, that prolintane has a certain level of abuse potential and should be considered carefully as a valuable basis for legal restrictions on use.


Asunto(s)
Conducta Animal/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/farmacología , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/metabolismo , Dopamina/metabolismo , Locomoción/efectos de los fármacos , Pirrolidinas/farmacología , Animales , Estimulantes del Sistema Nervioso Central/administración & dosificación , Ratones , Pirrolidinas/administración & dosificación , Ratas , Autoadministración , Trastornos Relacionados con Sustancias
9.
Food Chem ; 374: 131493, 2022 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-34802809

RESUMEN

Soy isoflavones (SIs) show various health benefits, such as antioxidant and estrogenic effects. It is important to understand the bioaccessibility and bioavailability of SIs due to the close relation to their bioactivities. In this study, the antioxidant capacity, bioaccessibility, and bioavailability of 12 SIs were evaluated using radical-scavenging methods, simulations of human digestion, and Caco-2 cells in Transwell, respectively. All SIs were stable (91.1-99.2%) under gastric digestion conditions compared with the control (100%), whereas acetyl and malonyl conjugates were unstable (38.5% and 65.5%, respectively) under small intestinal digestion conditions. SI aglycones showed higher permeability (7-15 times) and cellular accumulation (8.8 times) than their glucosides. A small amount of SI conjugates was intact in the cell and in the basolateral side of each Transwell. These results suggest that SI conjugates, especially malonyl and acetyl forms, have incidental bioactivity after being metabolized to aglycones inside the cell.


Asunto(s)
Glycine max , Isoflavonas , Antioxidantes , Disponibilidad Biológica , Células CACO-2 , Digestión , Humanos
11.
J Agric Food Chem ; 69(20): 5764-5773, 2021 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-33973775

RESUMEN

Common buckwheat sprout (CBS) contains more flavone C-glycosides (FCGs) and flavonol O-glycosides (FOGs) than does common buckwheat seed. Both flavonoids in CBS are well known for providing benefits to human health. However, they are relatively less bioaccessible and more directly degradable to aglycone during digestion than are multiglycosylated flavonoids. To overcome such limitations, the water solubility and digestion stability of FCGs and FOGs were enhanced by transglycosylation using cyclodextrin glycosyltransferase. Gastric conditions had little effect on the stability of FCGs and FOGs and their enzyme-modified compounds. In contrast, under intestinal conditions, transglycosylated FCGs lost a glucose moiety and reverted to their parent compounds before transglycosylation. Under colonic fermentation using human fecal samples, the different profiles and concentrations of short-chain fatty acids were suggested to be mainly due to the presence of transglycosylated FCGs and FOGs. These findings indicate that the process of transglycosylation changes the bioaccessibility of flavonoids in CBS.


Asunto(s)
Fagopyrum , Digestión , Fermentación , Flavonoides , Glicósidos , Humanos , Extractos Vegetales
12.
Emerg Infect Dis ; 16(12): 1938-42, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21122225

RESUMEN

To identify oseltamivir resistance, we analyzed neuraminidase H275Y mutations in samples from 10 patients infected with pandemic (H1N1) 2009 virus in South Korea who had influenza that was refractory to antiviral treatment with this drug. A neuraminidase I117M mutation that might influence oseltamivir susceptibility was detected in sequential specimens from 1 patient.


Asunto(s)
Antivirales/uso terapéutico , Brotes de Enfermedades , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Subtipo H1N1 del Virus de la Influenza A/genética , Gripe Humana/tratamiento farmacológico , Neuraminidasa/genética , Oseltamivir/uso terapéutico , Sustitución de Aminoácidos , Antivirales/farmacología , Preescolar , Farmacorresistencia Viral , Femenino , Humanos , Lactante , Gripe Humana/epidemiología , Gripe Humana/virología , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Datos de Secuencia Molecular , Oseltamivir/farmacología , República de Corea/epidemiología , Proteínas Virales/genética
13.
Neurosci Lett ; 715: 134620, 2020 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-31711977

RESUMEN

OBJECTIVE: Methamphetamine is a drug abused worldwide. Even though its abuse is a serious problem in many countries, there are few safe and effective therapies to treat addiction. In a previous study, music therapy attenuated relapse to morphine. Based on the study, we investigated whether music therapy suppresses the reinstatement of methamphetamine self-administration behavior. METHODS: Male Sprague-Dawley rats were trained to intravenously self-administer methamphetamine (0.1 mg/kg) using a fixed ratio 1 schedule in a daily 2 h session. Following 3 weeks of training, rats who had established a stable daily intake were subjected to extinction for 1 week. On the next day, priming injection was performed to induce reinstatement. Music therapy was played twice daily during the extinction period and immediately before the test session. In the second experiment, the selective GABAA and GABAB receptor antagonists were treated prior to the last music therapy to investigate a possible neuronal mechanism. Immunofluorescence was performed to immunohistochemically examine the behavioral effects. RESULTS: The meditation music by Young-Dong Kim but not the control music by Jeff Beck reduced active lever responding during the reinstatement session. And the effects of music therapy were blocked by GABA receptors antagonists. Also, immunofluorescence showed the pattern of c-Fos expression in the nucleus accumbens paralleled the behavioral results. CONCLUSION: Results of the present study suggest that meditation music by Young-Dong Kim can be a useful therapy to prevent the reinstatement of methamphetamine addiction during abstinence.


Asunto(s)
Comportamiento de Búsqueda de Drogas/efectos de los fármacos , Meditación , Metanfetamina/efectos adversos , Musicoterapia/métodos , Música , Recurrencia , Prevención Secundaria/métodos , Animales , Extinción Psicológica , Antagonistas de Receptores de GABA-A/farmacología , Antagonistas de Receptores de GABA-B/farmacología , Masculino , Núcleo Accumbens/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , República de Corea , Autoadministración
14.
Osong Public Health Res Perspect ; 11(1): 3-7, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32149036

RESUMEN

OBJECTIVES: Following reports of patients with unexplained pneumonia at the end of December 2019 in Wuhan, China, the causative agent was identified as coronavirus (SARS-CoV-2), and the 2019 novel coronavirus disease was named COVID-19 by the World Health Organization. Putative patients with COVID-19 have been identified in South Korea, and attempts have been made to isolate the pathogen from these patients. METHODS: Upper and lower respiratory tract secretion samples from putative patients with COVID-19 were inoculated onto cells to isolate the virus. Full genome sequencing and electron microscopy were used to identify the virus. RESULTS: The virus replicated in Vero cells and cytopathic effects were observed. Full genome sequencing showed that the virus genome exhibited sequence homology of more than 99.9% with SARS-CoV-2 which was isolated from patients from other countries, for instance China. Sequence homology of SARS-CoV-2 with SARS-CoV, and MERS-CoV was 77.5% and 50%, respectively. Coronavirus-specific morphology was observed by electron microscopy in virus-infected Vero cells. CONCLUSION: SARS-CoV-2 was isolated from putative patients with unexplained pneumonia and intermittent coughing and fever. The isolated virus was named BetaCoV/Korea/KCDC03/2020.

15.
Neuroreport ; 31(4): 352-358, 2020 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-32058432

RESUMEN

Methamphetamine is one of the widely abused drugs. Nevertheless, there is little predominant therapy for the abuse. In the previous study, acupuncture had shown to attenuate methamphetamine self-administration behavior, and based on, the present study investigated whether acupuncture inhibits the reinstatement of methamphetamine self-administration. As well, a possible neuronal mechanism was investigated. Male Sprague-Dawley rats weighing 270-300 g were trained to intravenously self-administer methamphetamine (0.1 mg/kg) for 3 weeks. Following training, rats who administered stable amount of methamphetamine underwent extinction period of 1 week. Thereafter, priming injection was performed to induce reinstatement, and acupuncture was given immediately before priming. In the second experiment, the selective antagonists of GABAA and GABAB receptors were treated prior to acupuncture to investigate a neuronal mechanism of GABAergic pathway. Acupuncture treatment at HT7, but not at the control acupoint LI5, reduced the active lever responses on the reinstatement session, showing that HT7 suppressed craving for methamphetamine induced by reexposure to the drug during abstinence. And, the effects of acupuncture were blocked by the GABA receptors' antagonists. In addition, HT7 did not influence saline self-administration, indicating that acupuncture effect was selective to the methamphetamine. Results of the present study show that acupuncture at HT7 suppresses reinstatement of methamphetamine self-administration behavior through the GABA receptor system without affecting the normal state. From the results, it may be suggested that acupuncture at HT7 can be a useful option in the treatment of methamphetamine addiction.


Asunto(s)
Terapia por Acupuntura/métodos , Estimulantes del Sistema Nervioso Central , Comportamiento de Búsqueda de Drogas/fisiología , Extinción Psicológica , Metanfetamina , Trastornos Relacionados con Sustancias/prevención & control , Animales , Antagonistas de Receptores de GABA-A/farmacología , Masculino , Ratas , Ratas Sprague-Dawley , Trastornos Relacionados con Sustancias/metabolismo
16.
RSC Adv ; 10(71): 43514-43522, 2020 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-35519706

RESUMEN

Invasive bioelectrodes are widely used as an effective treatment for several acute and chronic diseases. In earlier work using high surface area invasive porous bioelectrodes evaluated in an animal model of alcoholism withdrawal, we demonstrated significantly improved electrophysiological and behavioral responses. In this study, we further modify the surface of these invasive porous bioelectrodes with noble metal (Ag, Au, Pt) nanoparticles. Compared to both conventional and porous bioelectrodes, noble metal sensitized invasive porous bioelectrodes show markedly increased low threshold (LT) and wide dynamic range (WDR) neuronal activity. In particular, Pt-sensitized invasive porous bioelectrodes show the highest WDR neuronal activity only upon insertion. In addition, Ag-sensitized invasive porous bioelectrodes, whose surface area is about 37 times greater than that of conventional bioelectrodes, show improved electrochemical properties with higher LT and WDR neuronal activity when stimulated. In an animal model of chronic alcoholism, using normal and alcohol-treated Sprague-Dawley (SD) rats evaluated with the elevated plus maze (EPM) test, the Ag-sensitized invasive porous bioelectrodes show about 20% higher open arms time. These results suggest that these noble metal-sensitized invasive bioelectrodes may offer improved therapeutic outcomes for the treatment of chronic alcoholism, and given these enhanced electrophysiological properties, for other conditions as well.

17.
Antioxidants (Basel) ; 9(10)2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33086613

RESUMEN

Previous reports on phytochemicals in green tea (GT) and processed teas mainly focused on more representative compounds such as catechins. Here, we focus on the insignificantly studied non-catechin components in tea extracts, and explore the multivariate correlation between diverse phenolic compounds in tea and the in vitro antioxidant and anticancer effects. Extracts from GT and four types of processed teas were further divided into hydrophilic and hydrophobic fractions, whose phenolic compositions and antioxidant capacities were quantified using HPLC-MS and three antioxidant assays, respectively. For three types of teas, the anticancer effects of their extracts and fractions were assessed using cancer cell lines. The hydrophobic fractions had lower antioxidant capacities than the corresponding hydrophilic fractions, but exhibited superior antiproliferative effects on cancer cells compared with the whole extract and the hydrophilic fraction. Partial least squares-discriminant analysis revealed a strong correlation between the anticancer effects and the theaflavins and flavonols. Therefore, in addition to catechins, the hydrophobic fraction of tea extracts may have beneficial health effects.

18.
Osong Public Health Res Perspect ; 11(3): 112-117, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32528816

RESUMEN

OBJECTIVES: Coronavirus Disease-19 (COVID-19) is a respiratory infection characterized by the main symptoms of pneumonia and fever. It is caused by the novel coronavirus severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2), which is known to spread via respiratory droplets. We aimed to determine the rate and likelihood of SARS-CoV-2 transmission from COVID-19 patients through non-respiratory routes. METHODS: Serum, urine, and stool samples were collected from 74 hospitalized patients diagnosed with COVID-19 based on the detection of SARS-CoV-2 in respiratory samples. The SARS-CoV-2 RNA genome was extracted from each specimen and real-time reverse transcription polymerase chain reaction performed. CaCo-2 cells were inoculated with the specimens containing the SARS-COV-2 genome, and subcultured for virus isolation. After culturing, viral replication in the cell supernatant was assessed. RESULTS: Of the samples collected from 74 COVID-19 patients, SARS-CoV-2 was detected in 15 serum, urine, or stool samples. The virus detection rate in the serum, urine, and stool samples were 2.8% (9/323), 0.8% (2/247), and 10.1% (13/129), and the mean viral load was 1,210 ± 1,861, 79 ± 30, and 3,176 ± 7,208 copy/µL, respectively. However, the SARS-CoV-2 was not isolated by the culture method from the samples that tested positive for the SARS-CoV-2 gene. CONCLUSION: While the virus remained detectable in the respiratory samples of COVID-19 patients for several days after hospitalization, its detection in the serum, urine, and stool samples was intermittent. Since the virus could not be isolated from the SARS-COV-2-positive samples, the risk of viral transmission via stool and urine is expected to be low.

19.
J Eukaryot Microbiol ; 56(5): 413-20, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19737193

RESUMEN

We investigated feeding by phototrophic red-tide dinoflagellates on the ubiquitous diatom Skeletonema costatum to explore whether dinoflagellates are able to feed on S. costatum, inside the protoplasm of target dinoflagellate cells observed under compound microscope, confocal microscope, epifluorescence microscope, and transmission electron microscope (TEM) after adding living and fluorescently labeled S. costatum (FLSc). To explore effects of dinoflagellate predator size on ingestion rates of S. costatum, we measured ingestion rates of seven dinoflagellates at a single prey concentration. In addition, we measured ingestion rates of the common phototrophic dinoflagellates Prorocentrum micans and Gonyaulax polygramma on S. costatum as a function of prey concentration. We calculated grazing coefficients by combining field data on abundances of P. micans and G. polygramma on co-occurring S. costatum with laboratory data on ingestion rates obtained in the present study. All phototrophic dinoflagellate predators tested (i.e. Akashiwo sanguinea, Amphidinium carterae, Alexandrium catenella, Alexandrium tamarense, Cochlodinium polykrikoides, G. polygramma, Gymnodinium catenatum, Gymnodinium impudicum, Heterocapsa rotundata, Heterocapsa triquetra, Lingulodinium polyedrum, Prorocentrum donghaiense, P. micans, Prorocentrum minimum, Prorocentrum triestinum, and Scrippsiella trochoidea) were able to ingest S. costatum. When mean prey concentrations were 170-260 ng C/ml (i.e. 6,500-10,000 cells/ml), the ingestion rates of G. polygramma, H. rotundata, H. triquetra, L. polyedrum, P. donghaiense, P. micans, and P. triestinum on S. costatum (0.007-0.081 ng C/dinoflagellate/d [0.2-3.0 cells/dinoflagellate/d]) were positively correlated with predator size. With increasing mean prey concentration of ca 1-3,440 ng C/ml (40-132,200 cells/ml), the ingestion rates of P. micans and G. polygramma on S. costatum continuously increased. At the given prey concentrations, the maximum ingestion rates of P. micans and G. polygramma on S. costatum (0.344-0.345 ng C/grazer/d; 13 cells/grazer/d) were almost the same. The maximum clearance rates of P. micans and G. polygramma on S. costatum were 0.165 and 0.020 microl/grazer/h, respectively. The calculated grazing coefficients of P. micans and G. polygramma on co-occurring S. costatum were up to 0.100 and 0.222 h, respectively (i.e. up to 10% and 20% of S. costatum populations were removed by P. micans and G. polygramma populations in 1 h, respectively). Our results suggest that P. micans and G. polygramma sometimes have a considerable grazing impact on populations of S. costatum.


Asunto(s)
Diatomeas , Dinoflagelados/fisiología , Conducta Alimentaria , Animales , Dinoflagelados/química , Dinoflagelados/ultraestructura , Microscopía Confocal , Microscopía Electrónica de Transmisión , Microscopía Fluorescente
20.
Foods ; 8(11)2019 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-31689931

RESUMEN

Buckwheat sprouts that are synthesized during the germination process are rich in flavonoids, including orientin, vitexin, rutin, and their isomers (isoorientin, isovitexin, and quercetin-3-O-robinobioside, respectively). The purpose of this study was to optimize and validate an analytical method for separating flavonoid isomers in common buckwheat sprout extract (CSE). Factors, such as range, linearity, precision, accuracy, limit of detection, and limit of quantification, were evaluated for each standard using high-performance liquid chromatography (HPLC). On the basis of resolution and symmetry, a column temperature of 40 °C with 0.1% (v/v) acidic water and acetonitrile as mobile phases, at a flow rate of 1 mL min-1 were determined to be the optimal analytical conditions. Calibration curves for orientin, isoorientin, vitexin, isovitexin, and rutin exhibited good linearity with correlation coefficients of 0.9999 over the 6.25-100.00 µg mL-1 range. Recovery values of 96.67-103.60% confirmed that the method was accurate for all flavonoids. The relative standard deviations of intra-day repeatability and inter-day reproducibility confirmed method preciseness, with values of less than 5.21% and 5.40%, respectively. The developed method was used to analyze flavonoids in CSE, with isomers satisfactorily separated and simultaneously quantified. We demonstrated that the developed HPLC method can be used to monitor flavonoids in buckwheat sprouts.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA