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1.
J Nurs Scholarsh ; 56(4): 554-562, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38467584

RESUMO

INTRODUCTION: In the rapidly evolving healthcare landscape, the capacity to foster innovative work behavior among nurses is increasingly important. This study examined the dynamics between inclusive leadership, psychological safety, collectivism, and innovative work behavior among nurses. DESIGN: The study used a cross-sectional, correlational design. METHODS: This study utilized data from 730 medical-surgical nurses who provided direct care to patients. Standardized instruments were used to assess key study variables. Statistical analyses, including moderated mediation regressions, were employed to investigate the complex interplay among these variables. RESULTS: We found a positive association between inclusive leadership and innovative work behavior, and psychological safety mediated this relationship. Collectivism moderated inclusive leadership's direct relationship with psychological safety and its indirect relationship with innovative work behavior. The results revealed that nurses with lower levels of collectivism were more responsive to their managers' inclusive behaviors, strengthening the relation between inclusive leadership, psychological safety, and innovative work behavior. CONCLUSION: Our findings suggest that promoting inclusive leadership behaviors among nurse managers to create a psychologically safe environment can motivate nurses to engage in innovative work behavior. However, it is also important to understand that the effectiveness of leadership may differ depending on the collectivist values of individual nurses. CLINICAL RELEVANCE: Nurse managers should adopt inclusive leadership behaviors, such as valuing trust, open communication, and diversity, in order to foster psychological safety and innovative work behavior among nurses.


Assuntos
Liderança , Enfermeiros Administradores , Humanos , Estudos Transversais , Feminino , Masculino , Adulto , Enfermeiros Administradores/psicologia , Pessoa de Meia-Idade , Recursos Humanos de Enfermagem Hospitalar/psicologia , Atitude do Pessoal de Saúde , Inquéritos e Questionários , Segurança Psicológica
2.
Skin Res Technol ; 25(1): 96-99, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30055047

RESUMO

BACKGROUND: The standard diagnostic test for allergic contact dermatitis is the patch test, which can also be used to identify irritant contact dermatitis. Doubtful reactions (?+) can be often clinically relevant to individuals and can require additional tests. OBJECTIVES: The purpose of this study was to examine whether autofluorescence (AF) measurements in patients with doubtful reactions are helpful in diagnosing contact dermatitis. METHODS: Patients with a history of contact dermatitis were patch tested on the upper back for 48-hours of occlusion using aqueous solutions of 5% sodium lauryl sulfate. Reaction intensity was scored, and AF was measured on reactive lesions and non-lesions. Three dermatologists classified the results as positive or negative using the fluorescence photographs of patients with a doubtful reaction. RESULTS: Among doubtful reactions, the R/G% values were significantly higher in the AF- based positive group than in the negative group (P = .0086). On the other hand, the heterogeneity values of R, G, and B (HR, HG, HB) were significantly lower in the AF-based positive group (P = .0026, .0046, .0004 respectively). CONCLUSIONS: Measuring AF along with the clinical readings can help confirm doubtful patch test reactions.


Assuntos
Dermatite Alérgica de Contato/diagnóstico , Imagem Óptica/métodos , Testes do Emplastro/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
3.
Plant Dis ; 99(2): 292, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30699581

RESUMO

Cudrania tricuspidata (Moraceae) is a deciduous tree widely distributed in East Asia, including China, Korea, and Japan. It produces delicious fruit, and its cortex and root bark have been used as a traditional medicine to treat neuritis and inflammation. As C. tricuspidata has become known as a functional food, its cultivation area and production gradually have increased in Korea. However, information of viral disease in C. tricuspidata is very limited. In September 2012, open-field-grown C. tricuspidata trees showing virus-like symptoms of mosaic, yellowing, and distortion on the leaves were found in Naju, Korea. The fruit production in the diseased trees decreased to 20 to 40% of that in healthy trees. To identify causal agent(s), total RNA was isolated from the symptomatic leaves and used to generate a transcriptome library using the TruSeq Stranded Total RNA with Ribo-Zero Plant kit (Illumina, San Diego, CA) according to the manufacturer's instruction. The transcriptome library was analyzed by next-generation sequencing (NGS) using an Illumina HiSeq2000 sequencer. NGS reads were quality filtered and de novo assembled by the Trinity pipeline, and the assembled contigs were analyzed against the viral reference genome database in Genbank by BLASTn and BLASTx searches (3). The entire NGS procedure was perofrmed by Macrogen Inc. (Seoul, South Korea). Among the analyzed contigs, one large contig (10,043 bp) was of viral origin. Nucleotide blast searches showed that the contig has a maximum identity of 89% (with 100% coverage) to the isolate MS1 (Genbank Accession No. EU761198) of Bean common mosaic virus (BCMV), which was isolated from Macroptilium atropurpureum in Australia. The presence of BCMV was confirmed by a commercially available double-antibody sandwich (DAS)-ELISA kit (Agdia, Elkhart, IN). To confirm the BCMV sequence obtained by NGS, two large fragments covering the entire BCMV genome were amplified by reverse transcription-polymerase chain reaction (RT-PCR) using two sets of specific primers (5'-AAAATAAAACAACTCATAAAGACAAC-3' and 5'-AGACTGTGTCCCAGAGCATTTC-3' to amplify the 5' half of the BCMV genome; 5'-GCATCCTGAGATTCACAGAATTC-3' and 5'-GGAACAACAAACATTGCCGTAG-3' to amplify the 3' half of the BCMV genome) and sequenced. To obtain the complete genome sequence, the 5' and 3' terminal sequences were analyzed by the 5' and 3' rapid amplification of cDNA ends (RACE) method as described previously (1). The assembled full-length sequence of BCMV isolated from C. tricuspidata was 10,051 nucleotides in length without a poly(A) tail. It was deposited in Genbank under the accession number KM076650. BCMV, a member of the genus Potyvirus, is one of the most common viruses naturally infecting legumes, including Phaseolus vulgaris (2). In general, BCMV is known to have a restricted host range outside legume species (2). Therefore, the identification of BCMV from C. tricuspidata in this report is very exceptional. Because BCMV is easily transmitted by various aphids like other potyviruses, a large-scale survey may be required for exact investigation of the BCMV incidence in C. tricuspidata to prevent rapid spread of the virus. To the best of our knowledge, this is the first report of BCMV in C. tricuspidata. References: (1) H.-R. Kwak et al. Plant Pathol. J. 29:274, 2013. (2) M. Saiz et al. Virus Res. 31:39, 1994. (3) S.-E. Schelhorn et al. PLoS Comput. Biol. 9:e1003228, 2013.

4.
Plant Dis ; 98(12): 1748, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30703914

RESUMO

Leonurus sibiricus L. (family Lamiaceae) has been used as a traditional herbal remedy to treat various gynecologic diseases. Although it is a widely distributed subtropical weed in Southeast Asia, L. sibiricus have been commercially cultivated on a small scale in many geographic areas of Korea. In August 2012, field-grown L. sibiricus plants showing mosaic, yellowing, and stunting symptoms were collected near a pepper field in Andong, Korea. Since L. sibiricus is only consumed as a raw material of traditional medicine in Korea, symptomatic plants lose commercial value entirely. To identify the causal agent(s) of the virus-like symptoms, total RNA was extracted from the symptomatic leaves, and a transcriptome library was generated using the TruSeq Stranded Total RNA with Ribo-Zero plant kit (Illumina, San Diego, CA) according to the standard protocol. Next-generation sequencing (NGS) was performed using an Illumina HiSeq2000 sequencer. De novo assembly of the quality filtered NGS reads (101-bp paired-end reads) were performed using the Trinity pipeline and the assembled contigs (92,329 contigs) were analyzed against the viral reference genome database in GenBank by BLASTn and BLASTx searches (3). The entire NGS procedure was performed by Macrogen Inc. (Seoul, South Korea). Among the analyzed contigs, only two large contigs were clearly of viral origin. Nucleotide blast searches showed that the first and second contigs (5,914 and 3,534 bp, respectively) have maximum identities of 91 and 95% to RNA1 of the isolate RP3 (GenBank Accession No. JX183225) and RNA2 of the isolate RP7 (JX183234) of Broad bean wilt virus 2 (BBWV-2), which were isolated from pepper in Korea. The NGS results were confirmed by analyzing the sequences of the fragments covering the entire BBWV-2 genome amplified by RT-PCR using specific primers for BBWV-2 as described previously (1). To obtain the complete genome sequence, terminal sequences of both RNA segments were analyzed by the 5' and 3' rapid amplification of cDNA ends (RACE) method as described previously (1). The assembled full-length sequences of BBWV-2 RNA1 and RNA2 isolated from L. sibiricus were 5,951 and 3,575 nucleotides in length, respectively, and deposited in GenBank under the accessions KM076648 and KM076649, respectively. BBWV-2 belongs to the genus Fabavirus in the family Secoviridae and it is known to have a wide host range. To investigate the host range of the BBWV-2 isolated from L. sibiricus, sap from the symptomatic leaves of L. sibiricus was inoculated to the test plants including Nicotiana benthamiana, Capsicum annuum (red pepper), and C. annuum var. gulosum (Paprika). RT-PCR detection and sequencing of the amplicons showed that all the inoculated test plants were infected with the BBWV-2 isolated from L. sibiricus. Currently, BBWV-2 is epidemic in pepper fields in Korea (1,2). Because BBWV-2 is easily transmitted by various aphids, and L. sibiricus is widely distributed in both wild and cultivated fields in Korea, this host might serve as a potential source of BBWV-2 to other crops such as pepper. To the best of our knowledge, this is the first report of BBWV-2 in L. sibiricus. References: (1) H.-R. Kwak et al. Plant Pathol. J. 29:274, 2013. (2) H.-R. Kwak et al. Plant Pathol. J. 29:397, 2013. (3) S.-E. Schelhorn et al. PLoS Comput. Biol. 9:e1003228, 2013.

5.
Asian-Australas J Anim Sci ; 26(1): 50-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25049705

RESUMO

A facultative bacterium producing cellulolytic and hemicellulolytic enzymes was isolated from the rumen of a native Korean goat. The bacterium was identified as a Bacillus licheniformis on the basis of biochemical and morphological characteristics and 16S rDNA sequences, and has been designated Bacillus licheniformis JK7. Endoglucanase activities were higher than those of ß-glucosidase and xylanase at all temperatures. Xylanase had the lowest activity among the three enzymes examined. The optimum temperature for the enzymes of Bacillus licheniformis JK7 was 70°C for endoglucanase (0.75 U/ml) and 50°C for ß-glucosidase and xylanase (0.63 U/ml, 0.44 U/ml, respectively). All three enzymes were stable at a temperature range of 20 to 50°C. At 50°C, endoglucanse, ß-glucosidase, and xylanase had 90.29, 94.80, and 88.69% residual activity, respectively. The optimal pH for the three enzymes was 5.0, at which their activity was 1.46, 1.10, and 1.08 U/ml, respectively. The activity of all three enzymes was stable in the pH range of 3.0 to 6.0. Endoglucanase activity was increased 113% by K(+), while K(+), Zn(+), and tween 20 enhanced ß-glucosidase activity. Xylanase showed considerable activity even in presence of selected chemical additives, with the exception of Mn(2+) and Cu(2+). The broad range of optimum temperatures (20 to 40°C) and the stability under acidic pH (4 to 6) suggest that the cellulolytic enzymes of Bacillus licheniformis JK7 may be good candidates for use in the biofuel industry.

6.
Asian-Australas J Anim Sci ; 26(3): 358-65, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25049798

RESUMO

A series of in vitro studies were carried out to determine i) the effects of enzyme and formaldehyde treatment on the degradation characteristics of carbohydrate and protein sources and on the synchronicity of these processes, and ii) the effects of synchronizing carbohydrate and protein supply on rumen fermentation and microbial protein synthesis (MPS) in in vitro experiments. Untreated corn (C) and enzyme-treated corn (EC) were combined with soy bean meal with (ES) and without (S) enzyme treatment or formaldehyde treatment (FS). Six experimental feeds (CS, CES, CFS, ECS, ECES and ECFS) with different synchrony indices were prepared. Highly synchronous diets had the greatest dry matter (DM) digestibility when untreated corn was used. However, the degree of synchronicity did not influence DM digestibility when EC was mixed with various soybean meals. At time points of 12 h and 24 h of incubation, EC-containing diets showed lower ammonia-N concentrations than those of C-containing diets, irrespective of the degree of synchronicity, indicating that more efficient utilization of ammonia-N for MPS was achieved by ruminal microorganisms when EC was offered as a carbohydrate source. Within C-containing treatments, the purine base concentration increased as the diets were more synchronized. This effect was not observed when EC was offered. There were significant effects on VFA concentration of both C and S treatments and their interactions. Similar to purine concentrations, total VFA production and individual VFA concentration in the groups containing EC as an energy source was higher than those of other groups (CS, CES and CFS). The results of the present study suggested that the availability of energy or the protein source are the most limiting factors for rumen fermentation and MPS, rather than the degree of synchronicity.

7.
Asian-Australas J Anim Sci ; 25(11): 1568-74, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25049518

RESUMO

Three Holstein steers in the growing phase, each with a ruminal cannula, were used to test the hypothesis that the synchronization of the hourly rate of carbohydrate and nitrogen (N) released in the rumen would increase the amount of retained nitrogen for growth and thus improve the efficiency of microbial protein synthesis (EMPS). In Experiment 1, in situ degradability coefficients of carbohydrate and N in feeds including Korean rice wine residue (RWR) were determined. In Experiment 2, three total mixed ration (TMR) diets having different rates of carbohydrate and N release in the rumen were formulated using the in situ degradability of the feeds. All diets were made to contain similar contents of crude protein (CP) and neutral detergent fiber (NDF) but varied in their hourly pattern of nutrient release. The synchrony index of the three TMRs was 0.51 (LS), 0.77 (MS) and 0.95 (HS), respectively. The diets were fed at a restricted level (2% of the animal's body weight) in a 3×3 Latin-square design. Synchronizing the hourly supply of energy and N in the rumen did not significantly alter the digestibility of dry matter, organic matter, crude protein, NDF or acid detergent fiber (ADF) (p>0.05). The ruminal NH3-N content of the LS group at three hours after feeding was significantly higher (p<0.05) than that of the other groups; however, the mean values of ruminal NH3-N, pH and VFA concentration among the three groups were not significantly different (p>0.05). In addition, the purine derivative (PD) excretion in urine and microbial-N production (MN) among the three groups were not significantly different (p>0.05). In conclusion, synchronizing dietary energy and N supply to the rumen did not have a major effect on nutrient digestion or microbial protein synthesis (MPS) in Holstein steers.

8.
Biochemistry ; 50(16): 3288-99, 2011 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-21355570

RESUMO

Piscidin 4, an antimicrobial peptide recently isolated from mast cells of hybrid striped bass (Morone chrysops female × Morone saxatilis male), is unusual in that it is twice as long (44 amino acids) as the typical members of the piscidin family. We previously showed that native piscidin 4 had a modified amino acid at position 20, but synthetic piscidin 4 (having an unmodified Trp at position 20) had similar potent activity against a number of both human and fish bacterial pathogens. In this study, the structure and membrane topology of synthetic piscidin 4 were examined using liposomes as model bilayers. Circular dichroism analyses revealed that it had a disordered structure in aqueous solution and folded to form a relatively weak α-helical structure in both membrane-mimetic trifluoroethanol solutions and liposome suspensions. Fluorescence data (piscidin 4 embedded in liposomes) and leakage experiments indicated that piscidin 4 interacted strongly with the hydrophobic part of the liposome. Binding of piscidin 4 to liposomes induced significant blue shifts of the emission spectra of the single Trp residue (Trp20). Quenching of Trp20 by water-soluble quencher (either acrylamide or I-) indicated that the fluorescence of Trp20 decreased more in the presence of liposomes than in buffer solution, thus revealing that Trp20 is less accessible to the quenchers in the presence of liposomes. The relative leakage abilities of piscidin 4 (1 µM) with liposomes were in the following order: DPPC (100%)≥EYPC (94%)>DPPC/DPPG (65%)>EYPC/EYPG (0%). This high activity against DPPC and EYPC liposomes was contrary to our data suggesting that piscidin 4 has a much weaker tendency to form an α-helix than other piscidins, such as piscidin 1. However, the structural similarity of protozoan membranes to EYPC liposomes might explain our discovery of the potent activity of piscidin 4 against the important skin/gill parasite ich (Ichthyophthirius multifiliis), but its negligible hemolytic activity against vertebrate membranes (hybrid striped bass or human erythrocytes). It also suggests that other conformation(s) in addition to the α-helix of this peptide may be responsible for its selective activity. This differential toxicity also suggests that piscidin 4 plays a significant role in the innate defense system of hybrid striped bass and may be capable of functioning extracellularly.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Animais , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Bass , Dicroísmo Circular , Eritrócitos/efeitos dos fármacos , Hemólise , Humanos , Lipossomos/metabolismo , Estrutura Secundária de Proteína , Relação Estrutura-Atividade
9.
Protein Expr Purif ; 61(1): 36-44, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18595734

RESUMO

The cysteine-rich peptide hepcidin is an antimicrobial peptide and iron transport regulator that has been found in vertebrates including birds, fish and mammals. To elucidate the structure and biological function of fish hepcidin, which is difficult to produce synthetically, we have cloned several plasmid constructs encoding hepcidin from Japanese flounder, Paralichthys olivaceus, and tested expression of recombinant peptides, each with an N-terminal hexahistidine (6xHis) tag, in inclusion bodies or the periplasmic space of Escherichia coli. Hepcidin expressed in inclusion bodies was reduced, and subsequently refolded using a dilution technique with a cysteine redox system. The oxidized His-hepcidin monomer was separated from protein multimers and mass spectrometry analysis showed that the peptide was of the predicted size and contained four disulfide bonds. Removal of the 6xHis tag was attempted using enzymatic cleavage by Factor Xa and tobacco etch virus (TEV) protease or chemical cleavage by hydroxylamine. The Factor Xa cleavage was unsuccessful and hydroxylamine cleavage resulted in aggregation of cleaved peptide. TEV protease cleavage was successful but immediately resulted in hexamer formation despite varying reaction conditions (redox, non-redox, pH, temperature, target protein concentration, type of buffer). However, the recombinant His-hepcidin fusion peptide monomer showed considerable antimicrobial activity. NMR-based studies showed that hepcidin contained a rare vicinal disulfide linkage at the top of a loop structure and a short beta-sheet structure encompassing residues 7-13 and 19-25 that is stabilized by three disulfide bonds.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Animais , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Cromatografia Líquida , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Fator Xa/metabolismo , Linguado , Hepcidinas , Espectrometria de Massas , Ressonância Magnética Nuclear Biomolecular , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
11.
AJNR Am J Neuroradiol ; 27(6): 1373-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16775300

RESUMO

BACKGROUND AND PURPOSE: Although brain MR imaging findings in adult Wilson disease have been described in considerable detail, a paucity of information currently exists regarding brain MR imaging findings in pediatric Wilson disease. The purpose of this study was to analyze the brain MR imaging findings in Wilson disease of childhood at the initial stage and during follow-up after treatment and to correlate these observations with clinical response. METHODS: We evaluated 50 patients with pediatric Wilson disease. Fifty initial and 20 follow-up MR images from 15 patients following penicillamine treatment were analyzed retrospectively, and the data were correlated with clinical findings. RESULTS: Patients were categorized into 3 groups on the basis of initial MR imaging findings. Group I (n = 23) showed normal MR imaging findings. Group II (n = 15) was characterized by T1-weighted images with increased signal intensity in the globus pallidus (n = 15, 100%) followed by the putamen, midbrain, and caudate nucleus. Group III (n = 12) demonstrated T2-weighted images with increased signal intensity in the putamen (n = 10, 83%), followed by the caudate nucleus, globus pallidus, thalamus, midbrain, and pons. There was a significant difference in mean age, the presence of neurologic symptoms, and Child-Pugh classification among the 3 groups (P < .001). Following copper chelating therapy, the changes on follow-up MR imaging were strongly correlated with clinical response to treatment (P < .001). CONCLUSION: Brain MR imaging in children with Wilson disease can be categorized into distinct groups and demonstrated a significant correlation with clinical findings. Interval changes on follow-up MR imaging were also closely correlated with clinical findings and helpful in assessing the clinical response.


Assuntos
Encéfalo/patologia , Degeneração Hepatolenticular/patologia , Imageamento por Ressonância Magnética , Adolescente , Quelantes/uso terapêutico , Criança , Pré-Escolar , Feminino , Degeneração Hepatolenticular/tratamento farmacológico , Humanos , Masculino , Penicilamina/uso terapêutico
12.
J Leukoc Biol ; 65(2): 241-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10088607

RESUMO

Among the phagocytic leukocytes, monocytes have the important role of clearing out parasitic microorganisms. They accomplish this through production of toxic metabolites of oxygen. Trp-Lys-Tyr-Met-Val-D-Met (WKYMVm), a peptide that stimulates phosphoinositide (PI) hydrolysis in human leukocytes, including monocytes, binds to a unique cell surface receptor and stimulates superoxide generation, killing of Staphylococcus aureus, and activation of phospholipase D (PLD) in human monocytes. Preincubation of the cells with a PI-specific phospholipase C (PLC) inhibitor (U-73122), protein kinase C inhibitor (GF109203X), or intracellular Ca2+ chelator (BAPTA/AM) before the peptide stimulus totally inhibits the peptide-induced PLD activation and superoxide generation. On the other hand, tyrosine kinase inhibitor genistein only partially inhibits the peptide-induced processes. The peptide-induced bacteria killing activity shares regulatory mechanisms for PLD activation with the superoxide generation, which is inhibited in the presence of 1-butanol. We suggest that the peptide stimulates PLD downstream of PLC activation and PLD activation in turn is essential for the peptide-induced immunological functions such as the superoxide generation and killing of bacteria by human monocytes.


Assuntos
Monócitos/enzimologia , Oligopeptídeos/farmacologia , Fosfolipase D/metabolismo , Staphylococcus aureus , Superóxidos/metabolismo , Cálcio/metabolismo , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Humanos , Indóis/farmacologia , Maleimidas/farmacologia , Monócitos/imunologia , Monócitos/metabolismo , Oligopeptídeos/metabolismo , Receptores de Superfície Celular/metabolismo , Fosfolipases Tipo C/fisiologia
13.
Physiol Meas ; 36(6): 1179-92, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26008619

RESUMO

This paper describes a multiple background subtraction method in frequency difference electrical impedance tomography (fdEIT) to detect an admittivity anomaly from a high-contrast background conductivity distribution. The proposed method expands the use of the conventional weighted frequency difference EIT method, which has been used limitedly to detect admittivity anomalies in a roughly homogeneous background. The proposed method can be viewed as multiple weighted difference imaging in fdEIT. Although the spatial resolutions of the output images by fdEIT are very low due to the inherent ill-posedness, numerical simulations and phantom experiments of the proposed method demonstrate its feasibility to detect anomalies. It has potential application in stroke detection in a head model, which is highly heterogeneous due to the skull.


Assuntos
Técnica de Subtração , Tomografia/métodos , Encéfalo , Impedância Elétrica , Imageamento por Ressonância Magnética , Modelos Teóricos , Imagens de Fantasmas
14.
Endocrinology ; 138(2): 617-26, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9002995

RESUMO

Graves' disease is characterized by the overproduction of thyroid hormones due to the persistent stimulation of TSH receptor by autoantibodies. To determine the epitopes recognized by the autoantibodies, an enzyme-linked immunosorbent assay was developed that uses the human TSH receptor extracellular domain attached to plastic wells. The total IgG from some of the Graves' patients interacted with the bound TSH receptor (TSHR) at a significantly higher level than that in normal individuals. The IgG preparation that showed the highest binding activity was used for the identification of peptide sequences that prevent binding of Graves' IgG to TSHR from positional scanning synthetic peptide combinatorial libraries. A hexapeptide mixture, X1X2FDDA (X1 is a mixture of E, M, and Y; X2 is a mixture of E, H, and T), was found to be effective for inhibiting the binding of Graves' IgG to the TSHR. Further fractionation of X1X2FDDA showed that the following three sequences were highly effective: EEFDDA, ETFDDA, and EHFDDA. The second position of the three peptides did not appear to be important. The peptides also inhibited the cAMP synthesis induced by IgG of four of eight patients with Graves' disease tested. The synthesis of cAMP by TSH was also inhibited by the peptides to some extent. The peptide sequences most likely mimic a part of the conformational epitopes recognized by at least one class of Graves' IgG.


Assuntos
Doença de Graves/imunologia , Imunoglobulina G/imunologia , Biblioteca de Peptídeos , Peptídeos/farmacologia , Receptores da Tireotropina/imunologia , Sequência de Aminoácidos , AMP Cíclico/biossíntese , Eletroforese em Gel de Poliacrilamida , Expressão Gênica , Células HeLa , Humanos , Imunoglobulina G/farmacologia , Peptídeos/química , Receptores da Tireotropina/efeitos dos fármacos , Receptores da Tireotropina/genética , Proteínas Recombinantes de Fusão , Relação Estrutura-Atividade , Tireotropina/metabolismo
15.
Am J Trop Med Hyg ; 48(5): 610-25, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8517480

RESUMO

We report a case of massive hepatic infection by Capillaria hepatica in a 14-month-old girl who presented with the symptom triad of persistent fever, hepatomegaly, and leukocytosis with eosinophilia. Twenty-five cases of human infection with this parasite, mostly in children, have been reported in the literature. This is the first case of hepatic capillariasis reported in the Republic of Korea. The diagnosis was made by needle biopsy of the liver. Scanning electron microscopic examination of the biopsy specimen was also performed. Thiabendazole therapy was initiated and the patient developed liver disease-related IgA nephropathy during the therapy. The literature dealing with proven cases of infection with C. hepatica is briefly reviewed.


Assuntos
Capillaria/isolamento & purificação , Infecções por Enoplida , Hepatopatias Parasitárias , Animais , Biópsia por Agulha , Capillaria/ultraestrutura , Infecções por Enoplida/tratamento farmacológico , Infecções por Enoplida/patologia , Feminino , Hepatomegalia , Humanos , Lactente , Coreia (Geográfico) , Fígado/parasitologia , Fígado/patologia , Fígado/ultraestrutura , Hepatopatias Parasitárias/tratamento farmacológico , Hepatopatias Parasitárias/patologia , Microscopia Eletrônica de Varredura
16.
Mol Cells ; 10(4): 469-74, 2000 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-10987147

RESUMO

Phospholipase C (PLC)-gamma1 plays a pivotal role in the signal transduction pathway mediated by growth factors. In this study, we found that neurite outgrowth of pheochromocytoma (PC12) cells was significantly induced by interleukin-6 (IL-6). Stimulation of PC12 cells with IL-6 led to tyrosine phosphorylation of PLC-gamma1 in a dose- and time-dependent manner. IL-6 stimulation also increased the hydrolysis of phosphatidylinositol 4,5-bisphosphate. Accumulation of total inositol phosphate as well as tyrosine phosphorylation of PLC-gamma1 was inhibited by the pretreatment of protein kinase inhibitors such as genistein and staurosporine. These results suggest that PLC-gamma1 may be involved in the signal transduction pathway of IL-6-induced PC12 cell differentiation.


Assuntos
Interleucina-6/farmacologia , Isoenzimas/fisiologia , Neurônios/metabolismo , Fosfotirosina/metabolismo , Fosfolipases Tipo C/fisiologia , Animais , Genisteína/farmacologia , Fosfatos de Inositol/metabolismo , Isoenzimas/metabolismo , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Neurônios/citologia , Neurônios/efeitos dos fármacos , Células PC12 , Fosfolipase C gama , Fosforilação , Fosfotirosina/efeitos dos fármacos , Proteínas Tirosina Quinases/antagonistas & inibidores , Ratos , Transdução de Sinais , Fosfolipases Tipo C/metabolismo
17.
Int J Impot Res ; 12(2): 97-101, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11052635

RESUMO

A Korean multicenter study was conducted to assess the effectiveness of transurethral alprostadil with MUSE in 334 subjects with chronic erectile dysfunction (ED) who were enrolled in 21 clinical centers. Patients with psychogenic impotence comprised about 30% of subjects. Intraurethral alprostadil was titrated in a stepwise fashion in the clinics from 250 to 500 or 1000 mcg based on erectile response and tolerability. The erectile responses were evaluated using an erection assessment scale (score of 1-5). The dose that produced a maximal penile response of score 5 (full rigid erection) or 4 (full tumescence, partial rigidity) was selected for home treatment. Patients who showed partial erection (score of 3) with 1000 mcg were also included in the home-treatment group. In-clinic phase: 198 men (59.3%) had maximal penile responses of score 4 or 5. The rate of maximal responses was not related to patient age, etiology or duration of the ED. A total of 228 (68.3%) men progressed to home treatment. The overall level of comfort of the transurethral alprostadil was rated as uncomfortable or very uncomfortable in 12%. Home phase: During the two-month period of home treatment, 178 (78.1%) men had successful sexual intercourse at least once, and 78.2% of administrations (1976) resulted in successful intercourse. The main causes of drop-out were insufficient erectile response in 27 men (11.8%), adverse reactions (mostly penile or urethral pain) in 7 (3.1%) or both in 7 (3.1%). In conclusion, transurethral alprostadil could be a suitable treatment option for patients with ED regardless of age and etiology of ED. Efficacy in an Asian population (Korea) is comparable to that reported previously in Caucasians.


Assuntos
Alprostadil/administração & dosagem , Disfunção Erétil/tratamento farmacológico , Uretra , Vasodilatadores/administração & dosagem , Adulto , Idoso , Alprostadil/efeitos adversos , Alprostadil/uso terapêutico , Disfunção Erétil/psicologia , Humanos , Coreia (Geográfico) , Masculino , Pessoa de Meia-Idade , Mucosa , Satisfação do Paciente , Pênis/irrigação sanguínea , Qualidade de Vida , Autoadministração , Vasodilatadores/efeitos adversos , Vasodilatadores/uso terapêutico
18.
Clin Biochem ; 31(3): 137-41, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9629486

RESUMO

OBJECTIVES: Previously we reported that a synthetic peptide, WKYMVm, stimulates phosphoinositide (PI) hydrolysis in several hematopoietic cell lines and human neutrophils. In addition, the peptide induces superoxide generation in human neutrophils. The biochemical stimulation appeared to be mediated by specific receptors on leukocytes. In this report we try to find whether the specific receptor(s) exists on specific types of cells in human leukocytes. DESIGN AND METHODS: To study distribution of the peptide-specific receptors, we prepared a probe, biotin-labeled WKYMVm, and analyzed distribution of the peptide receptor using a biochemical study, cytochemical staining, and flow cytometric analysis. RESULTS: The peptide-specific receptors are expressed in several human leukocytes including granulocytes, monocytes, and B-lymphocytes but not T-lymphocytes and erythrocytes. CONCLUSIONS: These data suggest that the receptors for the peptide restricted to certain types of leukocytes and this specificity is probably related to the specific functions of the stimulated leukocytes.


Assuntos
Linfócitos B/metabolismo , Oligopeptídeos/metabolismo , Fosfatidilinositóis/metabolismo , Receptores de Peptídeos/metabolismo , Linfócitos T/metabolismo , Sequência de Aminoácidos , Cálcio/metabolismo , Humanos , Hidrólise , Células Tumorais Cultivadas
19.
Int Immunopharmacol ; 1(6): 1141-51, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11407308

RESUMO

Herbal medicines are increasingly being utilized to treat a wide variety of disease processes. Aqueous extract from the root of Platycodon grandiflorum A. DC (Campanulaceae), Changkil (CK), is reported to have antitumor and immunomodulatory activities; however, the mechanism underlying its therapeutic effect is not known. In the present study we examined the effects of CK on the release of nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha), and on the gene expression of iNOS and TNF-alpha in mouse macrophages. CK elicited a dose-dependent increase in NO and TNF-alpha production in cultured macrophages. CK significantly affected secretion at concentrations of more than 5 micrograms/ml, and its maximum effect was at concentration of 100 micrograms/ml. Reverse transcription polymerase chain reaction showed that increases in NO and TNF-alpha secretion were due to an increase in inducible NO synthase mRNA and TNF-alpha mRNA, respectively. Transient expression assays with NF-kappa B binding sites linked to the luciferase gene revealed that CK-induced increase of inducible NO synthase mRNA and TNF-alpha mRNA were mediated by the NF-kappa B transcription factor complex. These results demonstrate that CK stimulates NO and TNF-alpha release and is able to upregulate iNOS and TNF-alpha expression through NF-kappa B transactivation and this may be a mechanism whereby this herbal medicine elicits its therapeutic effects.


Assuntos
Macrófagos/metabolismo , Óxido Nítrico/metabolismo , Plantas Medicinais/química , Fator de Necrose Tumoral alfa/metabolismo , Animais , Feminino , Imunoensaio , Teste do Limulus , Luciferases/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/biossíntese , Nitritos/metabolismo , Extratos Vegetais/farmacologia , Raízes de Plantas/química , RNA/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Fator de Necrose Tumoral alfa/biossíntese , beta-Galactosidase/metabolismo
20.
Life Sci ; 65(17): 1845-56, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10576564

RESUMO

Trp-Lys-Tyr-Met-Val-Met (WKYMVM) is a novel potent peptide which can stimulate phosphoinositide hydrolysis in U937 as well as U266 and HL-60 cells (Baek et al., J. Biol. Chem. 271, 8170 (1996)). The peptide also induces superoxide generation in human neutrophils (Seo et al., J. Immunol. 158, 1896 (1997)). However, the signaling pathway down-stream of PLC set in motion by the peptide is not yet completely understood. We studied the signaling pathway of the peptide with the goal of elucidating the mechanism of the peptide's action. WKYMVM induced a rapid and transient activation of the ERKs in human histiocytic lymphoma cells, U937. The ERK1 activation peaked at 5 min and returned to the basal level after 30 min. The ERK1 stimulation by the peptide was partially inhibited by pretreatment of the cells with pertussis toxin (PTX), implicating G-protein involvement in the peptide's action. Pretreatment of staurosporine, protein kinase C (PKC) inhibitor, or PKC down-regulating PMA had no impact on the ERK1 activation by the peptide, indicating that the signaling pathway is independent of PKC activation. Pretreatment of the cells with neomycin and intracellular Ca2+ mobilizing reagents had also no effect on the ERK1 activation by the peptide. However, pretreatment with wortmannin or LY294002, the inhibitor of phosphatidylinositol 3 kinase (PI-3K), strongly inhibited peptide-stimulated ERK1 activation. Our results suggest that PI-3K may be an important participant in the ERK cascade induced by the peptide. Furthermore, the treatment of U937 cells with the peptide activated p74Raf-1, an upstream kinase of ERK. Taken together, our results suggest that the peptide activate ERK via a G-protein/PI-3K/Ras/Raf-1 mediated signaling pathway in U937 cells.


Assuntos
Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Oligopeptídeos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteína Quinase C/metabolismo , Western Blotting , Sinalização do Cálcio/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática , Proteínas de Ligação ao GTP/metabolismo , Humanos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Neomicina/farmacologia , Oligopeptídeos/síntese química , Proteínas Proto-Oncogênicas c-raf/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estimulação Química , Células U937
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