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1.
Hong Kong Med J ; 26(6): 479-485, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33284132

RESUMO

OBJECTIVES: To investigate the effects of pre-hospital stroke screening and notification on reperfusion therapy for patients with acute ischaemic stroke. METHODS: Pre-hospital stroke screening criteria were established based on a modified version of the Face Arm Speech Time (FAST) test. Screening was performed during ambulance transport by emergency medical service (EMS) personnel who completed a 2-hour training session on stroke screening. Temporal trends affecting acute ischaemic stroke investigation and intervention were compared before and after implementation of the pre-hospital screening. RESULTS: From July 2018 to October 2019, 298 patients with suspected stroke were screened by EMS personnel during ambulance transport prior to hospital arrival. Of these 298 patients, 213 fulfilled the screening criteria, 166 were diagnosed with acute stroke, and 32 received reperfusion therapy. The onset-to-door time was shortened by more than 1.5 hours (100.6 min vs 197.6 min, P<0.001). The door-to-computed tomography time (25.6 min vs 32.0 min, P=0.021), door-to-needle time (49.2 min vs 70.1 min, P=0.003), and door-to-groin puncture time for intra-arterial mechanical thrombectomy (126.7 min vs 168.6 min, P=0.04) were significantly shortened after implementation of the pre-hospital screening and notification, compared with historical control data of patients admitted from January 2018 to June 2018, before implementation of the screening system. CONCLUSION: Implementation of pre-hospital stroke screening using criteria based on a modified version of the FAST test, together with pre-arrival notification, significantly shortened the door-to-reperfusion therapy time for patients with ischaemic stroke. Pre-hospital stroke screening during ambulance transport by EMS personnel who complete a 2-hour focused training session is effective for identifying reperfusion-eligible patients with stroke.


Assuntos
Programas de Triagem Diagnóstica , Serviços Médicos de Emergência/métodos , AVC Isquêmico/diagnóstico , Reperfusão/estatística & dados numéricos , Tempo para o Tratamento/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Precoce , Auxiliares de Emergência/educação , Feminino , Implementação de Plano de Saúde , Humanos , AVC Isquêmico/terapia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos
2.
Int J Obes (Lond) ; 38(8): 1044-52, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24232498

RESUMO

OBJECTIVES: Activation of the Wnt/ß-catenin signaling pathway inhibits adipogenesis by maintaining preadipocytes in an undifferentiated state. We investigated the effect of indirubin-3'-oxime (I3O), which was screened as an activator of the Wnt/ß-catenin signaling, on inhibiting the preadipocyte differentiation in vitro and in vivo. METHODS: 3T3L1 preadipocytes were differentiated with 0, 4 or 20 µM of I3O. The I3O effect on adipocyte differentiation was observed by Oil-red-O staining. Activation of Wnt/ß-catenin signaling in I3O-treated 3T3L1 cells was shown using immunocytochemical and immunoblotting analyses for ß-catenin. The regulation of adipogenic markers was analyzed via real-time reverse transcription-PCR (RT-PCR) and immunoblotting analyses. For the in vivo study, mice were divided into five different dietary groups: chow diet, high-fat diet (HFD), HFD supplemented with I3O at 5, 25 and 100 mg kg(-1). After 8 weeks, adipose and liver tissues were excised from the mice and subject to morphometry, real-time RT-PCR, immunoblotting and histological or immunohistochemical analyses. In addition, adipokine and insulin concentrations in serum of the mice were accessed by enzyme-linked immunosorbent assay. RESULTS: Using a cell-based approach to screen a library of pharmacologically active small molecules, we identified I3O as a Wnt/ß-catenin pathway activator. I3O inhibited the differentiation of 3T3-L1 cells into mature adipocytes and decreased the expression of adipocyte markers, CCAAT/enhancer-binding protein α and peroxisome proliferator-activated receptor γ, at both mRNA and protein levels. In vivo, I3O inhibited the development of obesity in HFD-fed mice by attenuating HFD-induced body weight gain and visceral fat accumulation without showing any significant toxicity. Factors associated with metabolic disorders such as hyperlipidemia and hyperglycemia were also improved by treatment of I3O. CONCLUSION: Activation of the Wnt/ß-catenin signaling pathway can be used as a therapeutic strategy for the treatment of obesity and metabolic syndrome and implicates I3O as a candidate anti-obesity agent.


Assuntos
Adipogenia/efeitos dos fármacos , Fármacos Antiobesidade/farmacologia , Indóis/farmacologia , Síndrome Metabólica/metabolismo , Obesidade/metabolismo , Oximas/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Células 3T3-L1/efeitos dos fármacos , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Dieta Hiperlipídica , Masculino , Medicina Tradicional Chinesa , Síndrome Metabólica/tratamento farmacológico , Camundongos , Obesidade/tratamento farmacológico , Reação em Cadeia da Polimerase/métodos
3.
Plant Dis ; 97(8): 1118, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30722522

RESUMO

The hardy garden mum Chrysanthemum, or "mum" (Chrysanthemum × morifolium Ram.), is a popular flowering herbaceous perennial that is commonly grown for fall sales. In October 2011, suspected wilt disease was observed in potted hardy garden mums (cv. Guiin) grown in greenhouses in Jinju, South Korea. Symptoms included unilateral chlorosis of leaves at the stem apex. Wilted leaves occurred initially on the most severely affected side of the plant, but as the disease progressed, the entire plant wilted and died. Black necrosis and vascular discoloration at the base of stems always developed. Five fungal isolates, successfully isolated from 10 infected stems on potato dextrose agar (PDA), yielded rapidly growing floccose to felt-like colonies, initially white, but turning peach colored. The microconidia were ellipsoid, ovoid, and cylindrical, and measured 3 to 12 × 1 to 3 µm. The macroconidia were falcate, lunate, and measured 8 to 30 × 2 to 4 µm, and had 1 to 5 septa. Pathogenicity was studied in inoculated, potted plants in a greenhouse. A representative isolate of the fungus was grown on PDA at 20°C for about 10 days before inoculation. To obtain conidial suspensions, 10 ml of sterile distilled water (SDW) was added to the culture plates and scraped with a paintbrush to dislodge conidia. The suspension from the culture plates was filtered through cheesecloth and diluted to 2 × 104 micro- and macroconidia/ml with SDW. Nine 3-month-old hardy garden mums were planted in 20-cm-diameter plastic pots containing fine sand. After 10 days, the roots were cut to a depth of 5 cm on two sides of each plant at a distance of 2 cm from the stems. Then, 10 ml of conidial suspension were poured into each pot above the cuts roots, followed by 20 ml 12 days later. Three mums treated with SDW served as controls. Plants were fertilized twice weekly with 100 ml/pot of a nutrient solution (1) that lowered the soil pH and enhanced wilt development. Thirty days after inoculation, all of the artificially inoculated plants had wilted. The control mums remained healthy. The fungus was successfully reisolated to complete Koch's postulates. On the basis of the morphological characters, the fungus was identified as Fusarium oxysporum (3). To identify the isolated fungus, the complete internal transcribe spacer (ITS) rDNA and translation elongation factor 1-alpha (EF1-α) sequences were amplified using the primers ITS1/ITS4 and EF1/EF2, respectively, and sequenced. The resulting sequences were deposited in GenBank (Accession Nos. KC491873 and KC491875). A BLAST search of ITS rDNA (544 bp) and EF1-α (712 bp) sequences against a database of fungal isolates found 100% and 99% similarity to those of F. oxysporum, respectively. Fusarium wilt caused by F. oxysporim on C. morifolium has been previously recorded in North America and India but, to our knowledge, this is the first report of F. oxysporum causing wilt in hardy garden mum in Korea (2). F. oxysporum isolates causing wilts are specific to certain hosts and even to host varieties or cultivars. Further work is required to determine to which forma specialis and race the pathogen belongs. References: (1) A. W. Engelhard and S. S. Woltz. Proc. Fla. State Hort. Soc. 84:351, 1971. (2) H. C. Huang et al. Plant Pathol. Bull. 1:57, 1992. (3) C. V. Subramanian. CMI Descriptions of Pathogenic Fungi and Bacteria. No. 217, 1970.

4.
Nat Aging ; 3(9): 1144-1166, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37563227

RESUMO

Aging, often considered a result of random cellular damage, can be accurately estimated using DNA methylation profiles, the foundation of pan-tissue epigenetic clocks. Here, we demonstrate the development of universal pan-mammalian clocks, using 11,754 methylation arrays from our Mammalian Methylation Consortium, which encompass 59 tissue types across 185 mammalian species. These predictive models estimate mammalian tissue age with high accuracy (r > 0.96). Age deviations correlate with human mortality risk, mouse somatotropic axis mutations and caloric restriction. We identified specific cytosines with methylation levels that change with age across numerous species. These sites, highly enriched in polycomb repressive complex 2-binding locations, are near genes implicated in mammalian development, cancer, obesity and longevity. Our findings offer new evidence suggesting that aging is evolutionarily conserved and intertwined with developmental processes across all mammals.


Assuntos
Metilação de DNA , Epigênese Genética , Humanos , Camundongos , Animais , Metilação de DNA/genética , Envelhecimento/genética , Longevidade/genética , Mamíferos/genética
5.
Plant Dis ; 96(10): 1576, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30727345

RESUMO

Symptoms typical of center rot of onion (Allium cepa L.) were observed in farmers' fields in spring of 2009 and 2010 in Hamyang, South Korea, at an incidence of 30 to 50% (five affected fields representing approximately 6 ha). The symptoms were identical to those reported from infected onions in Georgia in 1997 (1). Harvested bulbs of symptomatic plants had reddish, collapsed scales near the neck. Symptomatic bulb tissues were surface-sterilized by immersing sections of the tissue for 30 s in 1% NaOCl, then rinsing the sections with sterilized, distilled water. Tissues were then macerated in 1 ml of sterilized, distilled water in a 1.5 ml Eppendorf tube using a sterile scalpel. The macerated tissue was left to soak for 10 min, after which a 5 µl suspension from each section was streaked onto plates of nutrient agar (NA). Gram-negative, rod-shaped, yellow bacteria were consistently recovered on NA. Three bacterial isolates recovered were each facultative anaerobes and induced a hypersensitive reaction on tobacco leaves. The biochemical test, API 20E (Biomérieux, Marcy l'Etoile, France), was also used for identification. All three strains tested positive for ß-D-galactosidase, utilization of citrate, and production of acetoin, catalase, and indole. All three strains tested negative for ornithine decarboxylase, lysine decarboxylase, urease, and oxidase. All produced acid from arabinose, glucose, mannitol, and sorbitol; while none produced acid from melibiose, inositol, and rhamnose. These characteristics are consistent with those of P. ananatis (1,2). Five bulbs were each surface-disinfested with 70% ethanol, dried, and injected with 50 µl of the appropriate bacterial suspension containing ~108 CFU/ml, using a syringe. The bulbs were placed in plastic boxes with four sheets of wet paper towel to maintain the relative humidity at 100%, and incubated at 25°C for 2 weeks. Three onion bulbs treated similarly but injected with sterilized, distilled water served as replicates of the control treatment. After 1 week of incubation, inoculated onion bulbs developed a brown discoloration and decay of the internal, fleshy scales matching those observed in the original farmers' fields. The control onion bulbs remained asymptomatic. Bacteria reisolated from lesions in the fleshy bulb scales of the inoculated bulbs had the same characteristics as the original isolates inoculated, proving Koch's postulates. Bacteria were not reisolated from any of the control bulbs. To confirm identity of the isolated bacteria, 16S rRNA and recA genes were amplified with primers 27mF: 5'-AGAGTTTGATCMTGGCTCAG-3' and 1492mR: 5'-GGYTACCTTGTTACGACTT-3', and PAGRECA21: 5'-GGTGAAGACCGCTCAATGGA-3' and PAGRECA621: 5'-CACCGATACGGCGGATATCA-3', respectively (3). Amplification of the 16S rRNA gene generated a 1,506-bp consensus sequence (GenBank Accession No. JQ762264), and amplification of the recA gene generated a consensus sequence of 601 bp (JQ762265). The 16S rRNA and recA gene sequences shared 99% nucleotide identity with those of a P. ananatis strain in GenBank (DQ195523 and AY219004, respectively). Based on symptoms, biochemical tests, and molecular analyses, the bacterium responsible for the onion symptoms in Korea was identified as P. ananatis. To our knowledge, this is the first report of center rot of onion caused by P. ananatis in Korea. References: (1) R. D. Gitaitis and J. D. Gay. Plant Dis. 81:1096, 1997. (2) H. G. Truper and L. de Clari. Int. J. Syst. Bacteriol. 47:908, 1997. (3) A. Wensing et al. Appl. Environ. Microbiol. 76:6248, 2010.

6.
Plant Dis ; 96(2): 292, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30731836

RESUMO

Kalanchoe (Kalanchoe blossfeldiana Poelln.) is widely cultivated in Korea as an ornamental houseplant and succulent garden plant because of its ease of propagation, low water requirements, and wide variety of flower colors. In August 2010, suspected nursery-stage kalanchoe leaf scorch was found at a grower's greenhouses located in Gimhae, Korea. In some greenhouses, 20 to 30%, and occasionally as much as 50%, of the plants were affected. Symptoms on kalanchoe include browning of the leaf margins and yellowing or darkening of tissues between the main leaf veins. As the disease progresses, affected leaves dried up, turned brown, and became brittle. A velvety, blackish olive mold formed on the surface of the dead tissue, followed by plant defoliation. Fresh leaf specimens were collected from infected plants and the causal pathogen was purified with a single-spore isolation technique and transferred onto potato dextrose agar (PDA). Colonies on PDA developed a gray or grayish brown, hairy, velvety mycelium that was mostly immersed and also formed conidia. Conidia were pale to mid brown, oblong, smooth or verruculose, with three to five transverse and one to two longitudinal septa in two to three transverse divisions, and 32 to 55 × 11 to 18 µm. Conidiophores were pale to mid brown, solitary or in fascicles, unbranched or occasionally branched, straight or flexuous, more or less cylindrical but enlarged slightly at one to three apical percurrent proliferations, septate, and 80 to 300 × 2 to 5 µm. A representative isolate of the pathogen was inoculated on kalanchoe leaves for pathogenicity testing. Cultures grown on PDA were flooded with sterile distilled water and after rubbing with an artist's paintbrush with hair bristles, the resulting suspensions were filtered through sterile cheesecloth. Conidial suspensions were adjusted to 2.5 × 104 conidia/ml with sterile distilled water. The leaves of five 1-month-old potted plants were wounded by applying pressure with forceps having serrated teeth, bruising the tissue. Wounded plants were sprayed with a conidial suspension until runoff. Five plants sprayed with sterile distilled water served as controls. The plants were maintained for 48 h at 25°C in a humidity chamber with 100% relative humidity and were then moved to a greenhouse. Symptoms similar to those observed in the farmer's greenhouse developed on wounded leaves within 9 days. The causal pathogen was reisolated from the lesions to prove Koch's postulates. To confirm the identity of the fungus, the complete internal transcribed spacer (ITS) rDNA and glyceraldehyde 3-phosphate dehydrogenase (gpd) gene were amplified and sequenced (1). Amplification of the ITS region generated a 579-bp sequence (GenBank Accession No. HQ840713) and gpd was 558 bp (GenBank Accession No. JF776462). The ITS and gpd sequences were 100% similar to the sequences of Stemphylium xanthosomatis (GenBank Accession Nos. AF442804 and AF443903, respectively). On the basis of symptoms, mycological characteristics, pathogenicity, and molecular data, this fungus was identified as S. xanthosomatis. The type culture of the fungus is stored at the Korean Agricultural Culture Collection (KACC 45812), National Academy of Agricultural Science, Korea. To our knowledge, this is the first report of leaf scorch caused by S. xanthosomatis on kalanchoe in Korea. Reference: (1) M. P. S. Câmara et al. Mycologia 94:660, 2002.

7.
Plant Dis ; 95(5): 616, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-30731967

RESUMO

Sweet persimmon (Diospyros kaki L.), a fruit tree in the Ebenaceae, is cultivated widely in Korea and Japan, the leading producers worldwide (2). Sweet persimmon fruit with flyspeck symptoms were collected from orchards in the Jinju area of Korea in November 2010. The fruit had fungal clusters of black, round to ovoid, sclerotium-like fungal bodies with no visible evidence of a mycelial mat. Orchard inspections revealed that disease incidence ranged from 10 to 20% in the surveyed area (approximately 10 ha) in 2010. Flyspeck symptoms were observed on immature and mature fruit. Sweet persimmon fruit peels with flyspeck symptoms were removed, dried, and individual speck lesions transferred to potato dextrose agar (PDA) and cultured at 22°C in the dark. Fungal isolates were obtained from flyspeck colonies on 10 sweet persimmon fruit harvested from each of three orchards. Fungal isolates that grew from the lesions were identified based on a previous description (1). To confirm identity of the causal fungus, the complete internal transcribed spacer (ITS) rDNA sequence of a representative isolate was amplified and sequenced using primers ITS1 and ITS4 (4). The resulting 552-bp sequence was deposited in GenBank (Accession No. HQ698923). Comparison with ITS rDNA sequences showed 100% similarity with a sequence of Zygophiala wisconsinensis Batzer & Crous (GenBank Accession No. AY598855), which infects apple. To fulfill Koch's postulates, mature, intact sweet persimmon fruit were surface sterilized with 70% ethanol and dried. Three fungal isolates from this study were grown on PDA for 1 month. A colonized agar disc (5 mm in diameter) of each isolate was cut from the advancing margin of a colony with a sterilized cork borer, transferred to a 1.5-ml Eppendorf tube, and ground into a suspension of mycelial fragments and conidia in a blender with 1 ml of sterile, distilled water. The inoculum of each isolate was applied by swabbing a sweet persimmon fruit with the suspension. Three sweet persimmon fruit were inoculated per isolate. Three fruit were inoculated similarly with sterile, distilled water as the control treatment. After 1 month of incubation in a moist chamber at 22°C, the same fungal fruiting symptoms were reproduced as observed in the orchards, and the fungus was reisolated from these symptoms, but not from the control fruit, which were asymptomatic. On the basis of morphological characteristics of the fungal colonies, ITS sequence, and pathogenicity to persimmon fruit, the fungus was identified as Z. wisconsinensis (1). Flyspeck is readily isolated from sweet persimmon fruit in Korea and other sweet persimmon growing regions (3). The exposure of fruit to unusual weather conditions in Korea in recent years, including drought, and low-temperature and low-light situations in late spring, which are favorable for flyspeck, might be associated with an increase in occurrence of flyspeck on sweet persimmon fruit in Korea. To our knowledge, this is the first report of Z. wisconsinensis causing flyspeck on sweet persimmon in Korea. References: (1) J. C. Batzer et al. Mycologia 100:246, 2008. (2) FAOSTAT Database. Retrieved from http://faostat.fao.org/ , 2008. (3) H. Nasu and H. Kunoh. Plant Dis. 71:361, 1987. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, Inc., New York, 1990.

8.
Water Sci Technol ; 59(9): 1699-702, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19448303

RESUMO

Nitrification inhibition by silver nanoparticles (nanosilver) was evaluated by extant respirometry using enriched nitrifying bacteria isolated from wastewater treatment plants. Silver nanoparticles were more toxic than silver ions or silver chloride colloids, all of which did not disrupt cell membrane integrity at 1 mg/L Ag. The toxicity of silver nanoparticles was reduced in the presence of various anions, especially sulfide. The results suggest that silver nanoparticles have the same behaviour of surface complexation as silver ions, and inhibition by nanosilver in wastewater treatment may be removed by reaction of silver nanoparticles with soluble sulfide species.


Assuntos
Bactérias/efeitos dos fármacos , Nanopartículas Metálicas/química , Nitritos/química , Prata/farmacologia , Bactérias/metabolismo , Prata/química , Sulfetos/química , Eliminação de Resíduos Líquidos
10.
Mol Cell Biol ; 6(5): 1751-9, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-2878364

RESUMO

A library of recombinant bacteriophage was prepared from ts167 avian erythroblastosis virus-transformed erythroid precursor cells (HD6), and integrated proviruses from three distinct genomic loci were isolated. A subclone of one of these proviruses (pAEV1) was shown to confer temperature-sensitive release from transformation of erythroid precursor cells in vitro. The predicted amino acid sequence of the v-erbB polypeptide from the mutant had a single amino acid change when compared with the wild-type parental virus. When the wild-type amino acid was introduced into the temperature-sensitive avian erythroblastosis virus provirus in pAEV1, all erythroid clones produced in vitro were phenotypically wild type. The mutation is a change from a histidine to an aspartic acid in the temperature-sensitive v-erbB polypeptide. It is located in the center of the tyrosine-specific protein kinase domain and corresponds to amino acid position 826 of the human epidermal growth factor receptor sequence.


Assuntos
Alpharetrovirus/genética , Vírus da Leucose Aviária/genética , Transformação Celular Neoplásica , Eritroblastos/citologia , Genes Virais , Proteínas Virais/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Células Cultivadas , Embrião de Galinha , Clonagem Molecular , Fibroblastos/citologia , Mutação , Hibridização de Ácido Nucleico , Proteínas Oncogênicas v-erbB , Fenótipo , Transfecção
11.
Mol Cell Biol ; 5(6): 1307-17, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2863747

RESUMO

The nucleotide sequences of two chicken histone genes encoding replacement variant H3.3 polypeptides are described. Unlike the replication variant genes of chickens (and almost all other organisms), these genes contain intervening sequences; introns are present in both genes in the 5' noncoding and coding sequences. Furthermore, the replacement variant histone mRNAs are post-transcriptionally polyadenylated. The locations, but not the sizes, of the two introns within the coding segments of the two genes have been exactly conserved, whereas the intron positions in their respective 5' flanking regions differ. Although both H3.3 genes predict the identical histone polypeptide sequence, they are as different from one another as each of them is from a more common replication variant H3.2 gene in silent base substitutions within the coding sequences. Thus, the H3.3 polypeptide sequence has been precisely maintained over a great evolutionary period, suggesting that this class of histones performs a strongly selected biological function. Although replacement variant histones can account for more than 50% of the total H3 protein in the nuclei of specific chicken tissues, the steady-state level of H3.3 mRNA is nearly the same (and is quite low) in all tissues and ages of animals examined. These properties suggest novel mechanisms for the control of the basal histone biosynthesis which takes place outside of the S phase of the cell cycle.


Assuntos
Galinhas/genética , Histonas/genética , Fatores Etários , Animais , Sequência de Bases , Clonagem Molecular , Regulação da Expressão Gênica , Genes , Especificidade de Órgãos , Filogenia , Poli A/metabolismo , Splicing de RNA , RNA Mensageiro/metabolismo
12.
Cell Calcium ; 27(5): 269-80, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10859593

RESUMO

Sphingosine induces a biphasic increase in cytosolic-free Ca(2+)([Ca(2+)](i)) with an initial peak followed by a sustained increase in HL-60 cells differentiated into neutrophil-like cells. The initial peak is not affected by the presence of ethylene glycol bis (beta-aminoethyl ether) N, N, N', N-tetraacetic acid (EGTA) in the buffer and appears to be dependent on conversion of sphingosine to sphingosine -1-phosphate (S1P) by sphingosine kinase, since it is blocked by the presence of N, N-dimethylsphingosine (DMS), which, like sphingosine, causes a sustained increase itself. The sustained increase that is elicited by sphingosine or DMS is abolished by the presence of EGTA in the buffer. The sustained sphingosine-induced Ca(2+)influx does not appear due to Ca(2+)influx through store-operated Ca(2+)(SOC) channels, since the influx is not inhibited by SKF 96365, nor is it augmented by loperamide. In addition, sphingosine and DMS attenuate the Ca(2+)influx through SOC channels that occurs after depletion of intracellular stores by ATP or thapsigargin. Both the initial peak and the sustained increase in [Ca(2+)](i)elicited by sphingosine can be blocked by phorbol 12-myristate 13-acetate (PMA)-elicited activation of protein kinase C. Thus, in HL-60 cells sphingosine causes a mobilization of Ca(2+)from intracellular Ca(2+)stores, which requires conversion to S1P, while both sphingosine and DMS elicit a Ca(2+)influx through an undefined Ca(2+)channel and cause a blockade of SOC channels.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Células HL-60/efeitos dos fármacos , Lisofosfolipídeos , Esfingosina/análogos & derivados , Esfingosina/farmacologia , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/fisiologia , Sinalização do Cálcio/fisiologia , Células HL-60/fisiologia , Humanos , Fosfotransferases (Aceptor do Grupo Álcool)/farmacologia , Esfingosina/metabolismo
13.
FEBS Lett ; 289(1): 47-50, 1991 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-1832647

RESUMO

The possibility that the ml muscarinic receptor subtype can induce release of intracellular granules and transmitters was studied by transfecting a cultured mast cell line. RBL-2H3 cells, with the ml receptor gene. Comparisons were made between carbachol- and antigen-induced activation of various secretory responses. Like antigen, carbachol stimulated inositol phospholipid hydrolysis and release of arachidonic acid with concomitant dose-dependent secretion of granular contents. Carbachol also stimulated a biphasic increase in intracellular calcium, as measured by single cell fura-2 measurements. Although the kinetics of the carbachol-induced rise in intracellular calcium differed from that induced by antigen, they both utilized the same intracellular pool of calcium, and the second phase of the rise in intracellular calcium was dependent on extracellular calcium in both cases. Thus, the ml muscarinic receptor activates release of granules by a mechanism ostensibly similar to that of antigen.


Assuntos
Carbacol/farmacologia , Mastócitos/metabolismo , Receptores Muscarínicos/metabolismo , Aminoquinolinas , Animais , Antígenos/farmacologia , Ácido Araquidônico , Ácidos Araquidônicos/metabolismo , Cálcio/metabolismo , Linhagem Celular , Corantes Fluorescentes , Hidrólise , Fosfatos de Inositol/metabolismo , Fosfolipídeos/metabolismo , Ratos , Receptores Muscarínicos/genética , Transfecção , beta-N-Acetil-Hexosaminidases/metabolismo
14.
J Med Chem ; 34(3): 1063-8, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1672155

RESUMO

The 2- and 6-fluoro derivatives of the potent beta-adrenergic agonist 3-(tert-butylamino)-1-(3,4-dihydroxyphenoxy)-2-propanol were prepared and their adrenergic properties examined. The order of potency was as follows: beta-adrenergic activity (simulation of cyclic AMP formation in C6 glioma cells), 2-F = parent much greater than 6-F; beta 1-activity (rate of contraction, guinea pig atria), parent greater than 2-F much greater than 6-F; beta 2-activity (relaxation of guinea pig tracheal strip), 2-F greater than parent much greater than 6-F. The affinity of the 2-fluoro analogue for beta 1-adrenergic receptors (inhibition of the specific binding of [3H]dihydroalprenolol, rat cerebral cortical membranes) was 2 times greater, while the 6-fluoro analogue was 1450 times less than the parent. These results suggest that the aromatic rings of phenoxypropanolamine adrenergic agonists and phenylethanolamine adrenergic agonists bind in similar fashion to the adrenergic receptor, and that if interactions between fluorine and the side-chain hydroxyl group are critical in defining beta-adrenergic selectivity, the interactions are similar in both phenoxypropanolamines and phenylethanolamines.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Flúor , Propanolaminas/farmacologia , Agonistas Adrenérgicos beta/química , Agonistas Adrenérgicos beta/metabolismo , Animais , Membrana Celular/metabolismo , Córtex Cerebral/metabolismo , Fenômenos Químicos , Química , AMP Cíclico/metabolismo , Di-Hidroalprenolol/metabolismo , Glioma/metabolismo , Cobaias , Masculino , Estrutura Molecular , Relaxamento Muscular/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Propanolaminas/química , Propanolaminas/metabolismo , Ratos , Receptores Adrenérgicos beta/metabolismo , Relação Estrutura-Atividade , Traqueia/efeitos dos fármacos , Traqueia/fisiologia , Células Tumorais Cultivadas
15.
Cancer Lett ; 97(1): 83-91, 1995 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-7585483

RESUMO

We examined the inhibitory effect of an aqueous extract (referred to as KM-110) from Viscum album coloratum, a Korean mistletoe, on tumour metastasis produced by highly metastatic murine tumour cells, B16-BL6 melanoma, colon 26-M3.1 carcinoma and L5178Y-ML25 lymphoma cells, using experimental and spontaneous metastasis models in syngeneic mice. In experimental metastasis of B16-BL6 and colon 26-M3.1 cells, intravenous (i.v.) administration of KM-110 (100 micrograms/mouse) 1 day after tumour inoculation significantly inhibited lung metastasis of both tumour cells. The administration of KM-110 also exhibited a therapeutic effect on liver and spleen metastasis of L5178Y-ML25 lymphoma cells. Furthermore, in spontaneous metastasis of B16-BL6 melanoma cells, multiple administration of KM-110 into tumour-bearing mice resulted in significant inhibition of lung metastasis by tumour cells, as well as the suppressive activity to the growth of primary tumour. In in vivo analysis for tumour-induced angiogenesis, the i.v. administration of KM-110 suppressed tumour growth and inhibited the number of blood vessels oriented towards the tumour mass. In a bioassay, the culture supernatant (KM-110-treated medium) of murine peritoneal macrophages that had been stimulated with KM-110 (1-10 micrograms/ml) for 30 min followed by 24 h incubation in fresh medium showed a strong tumour necrosis factor-alpha (TNF-alpha) activity. In addition, KM-110-treated medium significantly inhibited the growth of in vitro cultures of rat lung endothelial (RLE) cells. These results suggested that the extract of Korean mistletoe inhibits tumour metastasis caused by haematogenous as well as non-haematogenous tumour cells, and that its antimetastatic effect results from the suppression of tumour growth and the inhibition of tumour-induced angiogenesis by inducing TNF-alpha.


Assuntos
Antineoplásicos/farmacologia , Erva-de-Passarinho/química , Metástase Neoplásica/prevenção & controle , Neoplasias Experimentais/patologia , Neovascularização Patológica/patologia , Plantas Medicinais , Animais , Antineoplásicos/química , Divisão Celular/efeitos dos fármacos , Feminino , Inibidores do Crescimento/farmacologia , Macrófagos Peritoneais/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Extratos Vegetais/farmacologia , Ratos , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/metabolismo
16.
Chest ; 110(1): 48-52, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8681662

RESUMO

OBJECTIVE: To assess the effectiveness of a program to improve care of adult patients hospitalized for asthma. DESIGN: Retrospective analysis of patient and house staff education, patterns of medication use, spacer use, peak flowmeter use, and length of stay before and after team intervention. SETTING: A 960-bed teaching hospital in New York City. PATIENTS: All patients admitted to the hospital with a primary diagnosis of acute asthma exacerbation for 2 separate similar calendar periods, 1 year apart, before and after program intervention. We excluded patients who were hospitalized for less than 24 h or greater than 10 days. The preintervention group comprised 61 patients and the postintervention group 65 patients, well matched in their demographic characteristics and severity of disease. INTERVENTIONS: Using a team approach, we analyzed the process of inpatient treatment of asthma exacerbation, identified root causes for quality deficiency, and implemented specific improvements in the process. These included dedicated nurses who focused on the education of care providers and patients, a personalized attending-intern educational approach, and improvement in the supply and delivery of spacers, peak flowmeters, and medications to the patients. RESULTS: There was a significant increase in use of spacers, peak flowmeters, and inhaled corticosteroids. Systemic corticosteroid and methylxanthine use declined. Length of stay was reduced without increasing early hospital readmission rates. CONCLUSIONS: This program improved the treatment process of adults hospitalized for asthma.


Assuntos
Asma/terapia , Hospitalização , Garantia da Qualidade dos Cuidados de Saúde , Doença Aguda , Adulto , Asma/diagnóstico , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto , Readmissão do Paciente , Estudos Retrospectivos
17.
Life Sci ; 43(5): 387-98, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2456442

RESUMO

The behavioral stimulant effects of xanthines, such as caffeine and theophylline, appear to involve blockade of central adenosine receptors. However, 3-isobutyl-1-methylxanthine (IBMX), a potent phosphodiesterase (PDE) inhibitor, produces behavioral depression. The effects of caffeine analogs on open field behavior of mice and potencies as antagonists of adenosine receptors and as inhibitors of three classes of brain PDE have been compared. 1,7-Dimethyl-3-propargylxanthine, 1,3,7-tripropargylxanthine, and 3,7-dimethyl-1-propargylxanthine, which have high affinity for adenosine receptors and weaker activity as PDE inhibitors, all increase behavioral activity. In contrast, 1,3,7-tripropylxanthine, a more potent inhibitor of the brain calcium-independent (Ca-indep) PDEs than 1,3,7-tripropargylxanthine, produces behavioral depression, even though both analogues are potent adenosine receptor antagonists. 7-Benzyl-IBMX, an active receptor antagonist and selective inhibitor of a brain calcium-dependent (Ca-dep) PDE, produces a slight behavioral activation. Xanthines that are potent adenosine receptor antagonists and relatively weak inhibitors of the Ca-indep PDEs reverse the depressant effects of N6-cyclohexyladenosine, while xanthines, such as 1,3,7-tripropylxanthine, that are potent inhibitors of the Ca-indep PDEs, do not. The results suggest that the behavioral effects of xanthines may be determined primarily by relative activity as adenosine receptor antagonists and as inhibitors of brain Ca-indep PDEs.


Assuntos
Cafeína/análogos & derivados , Atividade Motora/efeitos dos fármacos , Inibidores de Fosfodiesterase/farmacologia , Receptores Purinérgicos/efeitos dos fármacos , Teofilina/análogos & derivados , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cafeína/farmacologia , Cálcio/fisiologia , Técnicas In Vitro , Masculino , Camundongos , Ratos , Ratos Endogâmicos , Relação Estrutura-Atividade , Teofilina/farmacologia
18.
J Pharm Biomed Anal ; 15(9-10): 1265-70, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9226552

RESUMO

Effective monitoring of cefuroxim levels by micellar electrokinetic capillary chromatography with direct serum injection are discussed and compared with the HPLC method. With capillary electrophoresis (CE), in contrast to HPLC, good resolution and efficiency was demonstrated as well as low consumption of solvent and samples. The CE system was applied at 15 kV with UV detection at 274 nm using 150 mM sodium dodecyl sulfate in 20 mM sodium phosphate and borate (pH 9.0) as electrolyte. The results were seen within 12 min with efficiency approaching 182,000 theoretical plates. The coefficients of variations of migration time and peak area were less than 0.8 and 5.9%, respectively. The detection limits for quantitative determination were 0.28 microM level. Good linearity and recovery were also obtained in the range of serum levels usually encountered in clinical analysis with a correlation coefficient of r = 0.991 and 98-101% recovery. The monitoring of cefuroxim in human serum with micellar electrokinetic capillary chromatography (MECC) is demonstrated. Identification of cefuroxim in human serum with MECC is demonstrated. Identification of cefuroxim was performed by characterizing the sample peak in terms of the migration time and UV spectrum. Considering the results of our study, the CE method should by highly suitable for the separation of cefuroxim in biofluids.


Assuntos
Cefuroxima/sangue , Cefalosporinas/sangue , Cromatografia Gasosa/métodos , Cromatografia Líquida de Alta Pressão , Humanos , Injeções , Modelos Lineares , Micelas , Reprodutibilidade dos Testes
19.
Yonsei Med J ; 40(5): 460-6, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10565257

RESUMO

Since amniocentesis made prenatal diagnosis feasible in 1967, the method has been remarkably instrumental in obstetrical practice. A recent study conducted between 1980 and 1997 collected 11,000 amniocentesis procedures done at 10 university hospitals and tertiary centers in Korea. The study indicated that the use of amniocentesis on patients has increased steadily since 1980; however, the number has increased sharply for patients in the mid 1990's. In the 1980's, amniocentesis had been used primarily for patients in advanced maternal age groups (at least 35 years or older). In 1995, amniocentesis had been implemented for the detection of abnormal serum markers (37.6%), and by 1997, amniocentesis was involved in such diagnosis even more frequently (44.8%). Of the total number of uses, 270 (2.5%) involved the detection of chromosomal anomaly. In autosomal disorders, 96 Down syndrome, 33 Edward syndrome, and 6 Patau syndrome were diagnosed. In sex chromosomal anomaly, 10 Turner syndrome, and 10 Klinefelter syndrome were diagnosed. Added to that, 83 translocations, and 15 mosaicisms were diagnosed. Of the 322 cases with abnormal ultrasonographic findings, 21 (6.5%) resulted in chromosomal anomaly. The use of genetic amniocentesis as a prenatal diagnostic test for Korean women has risen 10-fold between 1988 and 1998. As stated earlier, amniocentesis had earlier been used primarily for those in advanced maternal age groups. Today, maternal serum markers and highly sensitive ultrasonic technology can detect many fetal anomalies which eventually necessitate amniocentesis.


Assuntos
Amniocentese , Aberrações Cromossômicas/epidemiologia , Adulto , Transtornos Cromossômicos , Feminino , Idade Gestacional , Humanos , Coreia (Geográfico)/epidemiologia , Idade Materna , Gravidez , Ultrassonografia Pré-Natal , alfa-Fetoproteínas/análise
20.
Appl Radiat Isot ; 56(1-2): 307-13, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11839033

RESUMO

We have developed a multi-channel time scaling method that is suitable for activity measurement of beta emitting nuclides by means of 3-PM Liquid Scintillation Counting, using non-extending dead times and linear amplifiers. Since it enables to obtain the accidental coincidences directly, the true values for both double and triple coincidences are determined by simply taking into account the correction due to dead times. The advantages of the method are demonstrated by studying the activity of 204Tl and 14C. The measured results were compared with those derived by using the mathematical formulae.

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