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1.
Insects ; 14(9)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37754702

RESUMO

In South Korea, both Sympetrum depressiusculum Sélys, 1841 (Odonata: Libellulidae), which is distributed throughout Europe and from Russia to the Korean Peninsula, and Sympetrum frequens Sélys, 1883, which is endemic to Japan, are recorded. However, the identity of South Korean populations and the validity of listing the two species have not yet been settled. In this study, we collected seventy-four individuals of Sympetrum species from South Korea (five localities), Russia, The Netherlands, and Japan. These samples were examined for morphology and sequenced for partial COI, 16S rRNA, and a nuclear internal spacer (ITS) region, after which these molecular data were combined with available public data from Russia, Japan, and The Netherlands. Major morphological characters that have been used to distinguish the two species and phylogenetic, network, and structure analyses all consistently suggest that South Korean populations form a single species. Consequently, it could be valid to treat South Korean populations as one species, S. depressiusculum, by applying the senior name. Nevertheless, the validity of maintaining each as an independent species in other countries may need additional study considering that our samples were focused more on South Korea and limited for Europe, Russia, and Japan.

3.
Arch Rehabil Res Clin Transl ; 4(3): 100215, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36123972

RESUMO

Objective: To investigate changes in ultrasound-derived muscle architecture parameters of the brachialis and correlations in patients with subacute stroke. Design: Prospective longitudinal observational study. Setting: Tertiary inpatient rehabilitation center. Participants: Fifty adult patients (N=50) who were recruited within the first month poststroke. The patients had a mean age of 57.2±12.3 years and 68.0% were male. The majority of patients had significant upper limb weakness with a low mean Motricity Index of 18.5±24.7 and median elbow flexor strength of grade 0. Intervention: Not applicable. Main Outcome Measures: Ultrasound of the intact and hemiparetic brachialis was performed at 3-time intervals: within 1 month of stroke onset and at 1 and 6 months after first assessment. Clinical variables captured included upper limb motor power and elbow flexor spasticity. Results: Compared to the intact brachialis, there was reduced muscle thickness (1.93 cm vs 2.07 cm, 1.86 cm vs 2.08 cm, 1.85 cm vs 2.05 cm; P=.022) and increased echo intensity (63.3 arbitrary units [AU] vs 56.8 AU, 69.4 AU vs 56.6 AU, 77.4 AU vs 58.2 AU; P<.001) in the hemiparetic brachialis at all assessment intervals (baseline, 1 month, 6 months). Reduction in muscle mass was greater in older patients, with the correlation coefficient ranging from -0.30 (P=.03) at baseline to -0.50 (P<.001) at 6 months. Presence of elbow flexor spasticity at 1-month assessment interval was associated with lower muscle mass reduction (1.93 cm vs 1.74 cm; P=.017), lower echo intensity (65.1 AU vs 75.1 AU; P=.023), and longer fascicle lengths (12.92 cm vs 9.83 cm; P=.002). Conclusions: Changes including decreased muscle thickness and increased echo intensity of the hemiparetic brachialis were noted over time. Elbow flexor spasticity at 1-month assessment interval appears to mitigate against these changes.

4.
Ann Rehabil Med ; 44(3): 181-194, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32475098

RESUMO

OBJECTIVE: To investigate the usefulness of goal attainment scaling (GAS) in intensive stroke rehabilitation during the subacute stage. METHODS: Medical records of subacute post-stroke patients who had undergone intensive rehabilitation under hospitalization, before and after the application of GAS, were collected. GAS was conducted at the initial evaluation of each patient. Specific goals were suggested by physical and occupational therapists and were determined by the responsible physiatrist. A 5-point scale was used for the GAS score after 4 weeks of rehabilitation according to the preset criteria of each goal. To evaluate the influence of GAS in rehabilitation practice, functional improvements were compared between two patient groups before (n=121) and after (n=141) GAS. To assess progress in GAS practice, the standard GAS score was calculated, and the changes were observed over a 3-year period. The standard GAS score converged to 50 points when the goal was achieved. The therapists who used GAS also completed a survey regarding its usefulness. RESULTS: There were no statistical differences in the motor and cognitive outcomes of the patient groups before and after applying GAS scoring. Successive yearly changes in the standard GAS scores showed progressive convergence to 50 points, signaling that the patient's goal-setting abilities improved. According to the survey, most therapists felt that GAS enhanced the quality of therapies (84.6%). CONCLUSION: GAS improved goal-setting for the rehabilitation of subacute post-stroke patients and might have a positive effect on rehabilitation.

5.
Korean J Pediatr ; 58(2): 52-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25774196

RESUMO

PURPOSE: This study aimed to investigate the relative weight gain at 2-week intervals up to 6 weeks after birth to predict retinopathy of prematurity (ROP) requiring treatment among very low birth weight infants. METHODS: A total of 211 preterm infants with birth weights <1,500 g and gestational age <32 weeks were retrospectively reviewed. The main outcome was the development of ROP requiring treatment. Body weight measurements were recorded daily. Relative weight gains (g/kg/day) were calculated at the second, fourth, and sixth week after birth. RESULTS: Of the 211 infants, 89 developed ROP, of which 41 spontaneously regressed and 48 with early treatment of ROP type I required laser treatment. The relative weight gain at 2, 4, and 6 weeks postnatal age was significantly lower in infants with ROP requiring treatment than in infants without ROP or those with spontaneous regression (P<0.001, P=0.005, and P=0.004, respectively). On logistic regression, poor relative weight gain in the first 2 weeks was found to be related to ROP requiring treatment (adjusted odds ratio, 0.809; 95% confidence interval, 0.695-0.941; P=0.006). Relative weight gain at 2 weeks postnatal age was significantly lower in infants with ROP requiring treatment compared to that in ROP requiring no treatment (P=0.012). CONCLUSION: Poor postnatal weight gain in the first 2 weeks of life is an important and independent risk factor for ROP requiring treatment. Postnatal weight gain can predict the development of severe ROP requiring treatment.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 134: 184-90, 2015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25011045

RESUMO

Proton-substitution effects of 4-hydroxy-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-6-one (HPPCO) on structural and photophysical properties were presented. HPPCO crystallized in the orthorhombic space group Pbca with an intermolecular hydrogen bonding between OH and oxygen atom of the carbonyl. The proton-substituted derivatives, 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl acetate (OPPCA) and 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl benzoate (OPPCB), crystallized in the monoclinic P21/c space group. For OPPCA and OPPCB, a weak interaction between carbonyl oxygen atom in the substituted group and carbon atom in the fused ring was responsible for three-dimensional arrangements. In addition, 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl furan-2-carboxylate (OPPCF), and 6-oxo-5-phenyl-6H-pyrido[3,2,1-jk]carbazol-4-yl naphthoate (OPPCN) were also synthesized. HPPCO and the four derivatives excited by ultraviolet (UV) light produced blue emission. Proton substitution of the OH group significantly increased the radiative transitions and moderately decreased the non-radiative transitions. Consequently the luminescence quantum yields of the derivatives enhanced more than 4.6-fold, no matter what the groups were substituted. Structural and optical properties were further determined using density functional theory (DFT) and ZINDO calculations. The planar structure of the pyridocarbazole-fused ring resulted in π→π(*) electronic transitions within the main frame, with an additional transition from the n(O) of carbonyl to the π(*) of the main frame. The three excited states that arose from these transitions were responsible for the blue luminescence.


Assuntos
Carbazóis/química , Medições Luminescentes/métodos , Modelos Moleculares , Piridinas/química , Técnicas de Química Sintética , Cristalografia por Raios X , Modelos Químicos , Estrutura Molecular , Prótons , Relação Estrutura-Atividade
7.
Aviat Space Environ Med ; 85(2): 187-90, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24597165

RESUMO

BACKGROUND: The traditional water displacement method for measuring limb volume is improved by adding ethanol to water. METHODS: Four solutions were tested (pure water, 0.5% ethanol, 3% ethanol, and 6% ethanol) to determine the most accurate method when measuring the volume of a known object. RESULTS: The 3% and 6% ethanol solutions significantly reduced (P < 0.001) the mean standard deviation of 10 measurements of a known sphere (390.1 +/- 0.25 mi) from 2.27 ml with pure water to 0.9 ml using the 3% alcohol solution and to 0.6 using 6% ethanol solution (the mean coefficients of variation were reduced from 0.59% for water to 0.22% for 3% ethanol and 0.16% for 6% ethanol). The spheres' volume measured with pure water, 0.5% ethanol solution, 3% ethanol solution, and 6% ethanol solution was 383.2 +/- 2.27 ml, 384.4 +/- 1.9 ml, 389.4 +/- 0.9 ml, and 390.2 +/- 0.6 ml, respectively. Using the 3% and 6% ethanol solutions to measure hand volume blindly in 10 volunteers significantly reduced the mean coefficient of variation for hand volumetry from 0.91% for water to 0.52% for the 3% ethanol solution (P < 0.05) and to 0.46% for the 6% ethanol solution (P < 0.05). The mean standard deviation from all 10 subjects decreased from 4.2 ml for water to 2.3 ml for 3% ethanol solution and 2.1 ml for the 6% solution. DISCUSSION: These findings document that the accuracy and reproducibility of hand volume measurements are improved by small additions of ethanol, most likely by reducing surface tension of water.


Assuntos
Antropometria/métodos , Etanol , Mãos/anatomia & histologia , Água , Adulto , Humanos , Masculino , Tamanho do Órgão , Reprodutibilidade dos Testes , Soluções
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 124: 256-64, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24486869

RESUMO

The synthesis and characterization of two europium(III) complexes, [Eu(L)(H2O)]Cl and [Eu(L)(phen)(H2O)]Cl (L=N,N'-bis(salicylidene)-3,6-dioxa-1,8-diaminooctanato and phen=1,10-phenanthroline) are reported. Exciting the Eu(III) complexes with near-UV light resulted in sensitized red luminescence by a transfer of energy from the triplet excited states of L to the Eu(III) ion. Introducing phen to the complex increased the quantum yield of the L-sensitized luminescence of [Eu(L)(phen)(H2O)](+) by more than 18 times relative to [Eu(L)(H2O)](+). The optimized structures and the configurational interaction singles (CIS) of the [Eu(L)(phen)(H2O)](+) and [Eu(L)(H2O)](+) molecules were theoretically studied using ab initio Hartree-Fock (HF). The theoretical calculations showed that the first nearly degenerate 1A and 2A excited states, more specifically the π→π(*) transitions of the two phenolate terminals, contributed significantly to the energy transfer process. Although the phen excitation route was forbidden in [Eu(L)(phen)(H2O)](+), the coordination of phen enhanced the absorbing ability of L markedly and caused the energy transfer from the 1A and 2A states to the (5)D1 and (5)D0 states of Eu(III) to predominate over any radiative and nonradiative processes occurring between the excited states and the ground states of the L moiety. Consequently, the quantum yield of the sensitized luminescence was enhanced significantly in [Eu(L)(phen)(H2O)](+).


Assuntos
Európio/química , Luminescência , Fenantrolinas/química , Bases de Schiff/química , Absorção Fisico-Química , Elétrons , Transferência de Energia , Modelos Moleculares , Teoria Quântica , Análise Espectral , Fatores de Tempo
9.
Langmuir ; 28(25): 9842-8, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22656326

RESUMO

A novel Eu(II) complex with 2-ethylhexyl hydrogen 2-ethylhexyl phosphonate (EHHEHP or PC88A) was synthesized and blended with polystyrene polymer (PS). Both an independent complex and the Eu(II)/PS blend excited by near-UV light produced blue luminescence, arising from the 5d→ 4f transitions of Eu(II). Time-dependent density functional theory (TD-DFT) calculations on electronic structures of the complex molecule indicated that the absorbing and emitting center was associated with the (2)A(d(z(2))) state under the C(2) crystal field. We also synthesized silver nanoparticles (Ag NPs) with an average particle size of 4.48 nm (σ = 0.91 nm) using EHHEHP as a stabilizer. The effects of Ag NPs as a colloidal suspension and an interfacial layer on the luminescence intensity of the blend were investigated as functions of the concentration of Ag NPs and the thickness of the Ag NP layer, respectively. The critical concentration of the colloidal Ag NPs and the critical thickness of the interfacial Ag NP layer were ∼355 ppm and ∼0.16 µm, respectively. Under critical conditions, the Ag NPs increased the luminescence intensity by 4.4 times as a colloidal suspension in CH(2)Cl(2) and 2.2 times as an interfacial-layer state.

10.
Korean J Med Educ ; 23(1): 33-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25814283

RESUMO

PURPOSE: Multimedia can be used to understand the basic anatomy and pathological features of the bladder, providing more intuitive knowledge than traditional education methods. Cystoscopy is one of the most fundamental and important diagnostic procedures for detecting pathology in the bladder. Thus, we developed a PC-based digitalized recording device and electronic document to create an electronic medical record to perform cystoscopy and used them for medical education. METHODS: To share them with an educatee, cystoscopic images from a camera unit were shown on the monitor of a personal computer, which was installed with an interface device with an S-VHS input. With these cystoscopic images, the operator could provide some information on important structures in the bladder, such as bilateral ureteral orifices, the verumontanum and the trigone to the educatee. Also, simple questionnaires were given to medical students to evaluate the effectiveness and value of this system. RESULTS: Cystoscopic images could be transferred to the monitor with considerable ease and quality through the personal computer. This system was effective and valuable in teaching the normal anatomy and pathology of the bladder. Also, based on the results of the questionnaire, we concluded that this system provides high-quality images that are sufficient to relay medical information and is superior to traditional methods with regard to educational effectiveness and increasing one's understanding of medical diseases. CONCLUSION: The PC-based recording system for cystoscopy substitutes for commercial recording devices for medical purposes, and provides sufficient medical information to medical students to allow them to understand the normal anatomy and pathological structure of the bladder.

11.
J Korean Neurosurg Soc ; 43(4): 205-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19096646

RESUMO

Astroblastoma is a rarely diagnosed primary brain neoplasm whose histogenesis has been clarified recently. It occurs in children and young adults and presents as a well circumscribed, contrast-enhancing lesion in the cerebral hemisphere. We present a case of 20-year-old woman with an astroblastoma in the left temporal convexity that was treated with total tumor resection alone. We thought the mass was extra-axial neoplasm based on radiological findings of computed tomography and magnetic resonance imaging initially, but later, we obtained angiographic findings suggesting an intra-axial neoplasm. The patient is doing well even two years after surgery. The characteristic radiological and histopathological features of this case are described with a literature review. An astroblastoma should be included in the differential diagnosis of a superficially located tumor presenting with the findings of an extra-axial mass, especially in a young patient.

12.
Biol Pharm Bull ; 31(4): 558-62, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18379040

RESUMO

Berberine is an isoquinoline plant alkaloid with a long history of being used for the treatment of many diseases in Chinese herbal medicine. Berberine has a wide range of biochemical and pharmacological effects, including antitumor activities, but its mechanism of action is not clearly understood. In this study, we investigated that the relationship between the antiproliferative activities of berberine and the apoptotic pathway associated with its molecular mechanism of action in human glioblastoma T98G cells. Berberine treatment of T98G cell lines inhibited cell proliferation and induced cell death in a dose (50-200 microg/ml) dependent manner with an IC50 value of 134 microg/ml, which was associated with an increase in G1 arrest. Western blot analysis showed that the berberine-induced G1 arrest was mediated through the increased expression of P27 and the decreased expression of cyclin-dependent kinase (CDK) 2, CDK4, cyclin D, and cyclin E proteins. Berberine treatment also markedly enhanced apoptosis in T98G cells through the induction of a higher ratio of the Bax/Bcl-2 proteins, the disruption of mitochondrial membrane potential, and the activation of procaspase-9, caspase-9, caspase-3, and poly(ADP-ribose) polymerase (PARP). Berberine can inhibit T98G cell proliferation by inducing G1 arrest and apoptosis. These results demonstrate that the berberine-induced apoptosis of T98G cells is primarily mediated through the mitochondrial/caspases-dependent pathway.


Assuntos
Apoptose/efeitos dos fármacos , Berberina/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Caspases/fisiologia , Fase G1/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Transdução de Sinais/fisiologia , Western Blotting , Neoplasias Encefálicas/patologia , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Sobrevivência Celular/efeitos dos fármacos , Glioblastoma/patologia , Humanos , Potenciais da Membrana/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
13.
Biomed Pharmacother ; 62(9): 630-6, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18325727

RESUMO

Curcumin, at high concentrations (>2 microM), inhibits the production of nitric oxide (NO) and the expression of inducible NO synthase (iNOS) through inactivation of nuclear factor (NF)-kappaB and, at low concentrations, induces the expression of heme oxygenase (HO)-1 in macrophages. Here, we demonstrated that curcumin at low concentrations (0.5-2 microM) can also inhibit NO production and iNOS expression in lipopolysaccharide (LPS)-activated RAW264.7 macrophages only when the cells were pretreated for at least 6h with curcumin. Curcumin induced dose- and time-dependent HO-1 expression, and this was coincident with the inhibitory effects of low concentrations of curcumin on NO production and iNOS expression. Blockage of HO-1 activity or knockdown of HO-1 expression abolished the inhibitory effects of curcumin. Over-expression of HO-1 or exogenous addition of carbon monoxide, a byproduct derived from heme degradation, mimicked the inhibitory action of low concentrations of curcumin. Moreover, LPS-induced NF-kappaB was diminished in macrophages subjected to prolonged treatment with low concentrations of curcumin. Treatment with HO inhibitor abolished the inhibitory effect of curcumin on LPS-induced NF-kappaB activation. Collectively, we provide evidence to support the important role of HO-1 in inhibition of NO production and iNOS expression by curcumin even at low concentrations.


Assuntos
Curcumina/farmacologia , Heme Oxigenase-1/biossíntese , Macrófagos/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Heme Oxigenase-1/genética , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/biossíntese
14.
Biophys Chem ; 125(2-3): 403-10, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17169480

RESUMO

Spectral properties including circular and linear dichroism (CD and LD) of M-DNA, a molecular electric wire, formed at a high Zn(2+) concentration have been studied using a minor groove binding drug 4',6-diamidino-2-phenylindole (DAPI) as a probe. As the Zn(2+) concentration increased, the magnitude of LD in the DNA absorption region decreased at pH 8.5, implying the aggregation of DNA, which is in contrast with the retained LD magnitude at pH 7.0. As the M-DNA formed, change in the secondary structure of DNA was observed by CD spectrum, which resembles that of the C-form DNA, although overall structure seemed to remain as a right handed double helix. The DAPI-DNA complex in the presence of high concentration of Zn(2+) ions at pH 7.0 exhibited the similar CD spectrum with that in the absence of Zn(2+) ion, consisting of type I, II and III. In contrast, at pH 8.5 at a high Zn(2+) concentration in which DNA is in its M-form, DNA bound DAPI produced only the type III CD, suggesting that DAPI binds at the surface of M-DNA: the presence of Zn(2+) ions prevents the minor groove binding of DAPI.


Assuntos
DNA/química , DNA/metabolismo , Indóis/química , Sítios de Ligação , Concentração de Íons de Hidrogênio , Conformação de Ácido Nucleico , Análise Espectral , Zinco
15.
Free Radic Biol Med ; 41(1): 106-19, 2006 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16781459

RESUMO

Hydrogen sulfide (H(2)S), a regulatory gaseous molecule that is endogenously synthesized by cystathionine gamma-lyase (CSE) and/or cystathionine beta-synthase (CBS) from L-cysteine (L-Cys) metabolism, is a putative vasodilator, and its role in nitric oxide (NO) production is unexplored. Here, we show that at noncytotoxic concentrations, H(2)S was able to inhibit NO production and inducible NO synthase (iNOS) expression via heme oxygenase (HO-1) expression in RAW264.7 macrophages stimulated with lipopolysaccharide (LPS). Both H(2)S solution prepared by bubbling pure H(2)S gas and NaSH, a H(2)S donor, dose dependently induced HO-1 expression through the activation of the extracellular signal-regulated kinase (ERK). Pretreatment with H(2)S or NaHS significantly inhibited LPS-induced iNOS expression and NO production. Moreover, NO production in LPS-stimulated macrophages that are expressing CSE mRNA was significantly reduced by the addition of L-Cys, a substrate for H(2)S, but enhanced by the selective CSE inhibitor beta-cyano-L-alanine but not by the CBS inhibitor aminooxyacetic acid. While either blockage of HO activity by the HO inhibitor, tin protoporphyrin IX, or down-regulation of HO-1 expression by HO-1 small interfering RNA (siRNA) reversed the inhibitory effects of H(2)S on iNOS expression and NO production, HO-1 overexpression produced the same inhibitory effects of H(2)S. In addition, LPS-induced nuclear factor (NF)-kappaB activation was diminished in RAW264.7 macrophages preincubated with H(2)S. Interestingly, the inhibitory effect of H(2)S on NF-kappaB activation was reversed by the transient transfection with HO-1 siRNA, but was mimicked by either HO-1 gene transfection or treatment with carbon monoxide (CO), an end product of HO-1. CO treatment also inhibited LPS-induced NO production and iNOS expression via its inactivation of NF-kappaB. Collectively, our results suggest that H(2)S can inhibit NO production and NF-kappaB activation in LPS-stimulated macrophages through a mechanism that involves the action of HO-1/CO.


Assuntos
Heme Oxigenase-1/metabolismo , Sulfeto de Hidrogênio/farmacologia , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/biossíntese , Animais , Monóxido de Carbono/metabolismo , Linhagem Celular , Heme Oxigenase-1/biossíntese , Humanos , Sulfeto de Hidrogênio/metabolismo , Sulfeto de Hidrogênio/toxicidade , Macrófagos/efeitos dos fármacos , Macrófagos/enzimologia , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Canais de Potássio/metabolismo , Sulfetos/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
16.
Biochim Biophys Acta ; 1760(7): 993-1000, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16580778

RESUMO

The binding site and the geometry of Co(III)meso-tetrakis(N-methylpyridinium-4-yl)porphyrin (CoTMPyP) complexed with double helical poly(dA).poly(dT) and poly(dG).poly(dC), and with triple helical poly(dA).[poly(dT)](2) and poly(dC).poly(dG).poly(dC)(+) were investigated by circular and linear dichroism (CD and LD). The appearance of monomeric positive CD at a low [porphyrin]/[DNA] ratio and bisignate CD at a high ratio of the CoTMPyP-poly(dA).poly(dT) complex is almost identical with its triplex counterpart. Similarity in the CD spectra was also observed for the CoTMPyP-poly(dG).poly(dC) and -poly(dC).poly(dG).poly(dC)(+) complex. This observation indicates that both monomeric binding and stacking of CoTMPyP to these polynucleotides occur at the minor groove. However, different binding geometry of CoTMPyP, when bind to AT- and GC-rich polynucleotide, was observed by LD spectrum. The difference in the binding geometry may be attributed to the difference in the interaction between polynucleotides and CoTMPyP: in the GC polynucleotide case, amine group protrude into the minor groove while it is not present in the AT polynucleotide.


Assuntos
Metaloporfirinas/química , Nucleotídeos/química , Porfirinas/farmacologia , Sítios de Ligação , Dicroísmo Circular , DNA/química , Concentração de Íons de Hidrogênio , Modelos Químicos , Conformação de Ácido Nucleico , Porfirinas/química , Ligação Proteica
17.
Biochim Biophys Acta ; 1760(3): 388-94, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16386850

RESUMO

The interactions between water-soluble cationic oxovanadyl[meso-tetrakis(4-N-methylpyridiumyl)]porphyrin (VOTMPyP) and various synthetic polynucleotide including poly[d(A-T)2], poly[d(G-C)2], and poly[d(I-C)2] were studied using absorption, circular dichroism (CD), and linear dichroism (LD) spectroscopy. When VOTMPyP formed a complex with poly[d(A-T)2] and poly[d(I-C)2], a positive CD signal at low [VOTMPyP]/[DNA] ratios (R ratios) and strong excitonic CD signals at above R > or = 0.15 were induced. The appearance of the CD spectra of the VOTMPyP-poly[d(G-C)2] complex were very different: a small negative CD at low R ratios and very small excitonic CD at high R ratios were observed. Considering the facts that the minor grooves of the former two polynucleotides resemble and the major groove of poly[d(I-C)2] is similar with that of poly[d(G-C)2], it is conclusive that VOTMPyP binds to the minor groove of all DNA at lower R ratios while they stack at the outside of DNA at higher R ratios. The binding geometry of VOTMPyP to all polynucleotides studied by LD seemed to be homogenous, irrespective of the R ratio. It has been found that VOTMPyP can have five- and six-fluxional coordination states. Comparing the absorption spectra of VOTMPyP complexed with poly[d(A-T)2] and poly[d(G-C)2], the distinctive absorptions of the five- and six-coordinated species were observed at lower R ratios which centered at 420-430 nm and 442 nm, respectively. While the six-coordinated VOTMPyP favored the poly[d(A-T)2], the five-coordinated species favored the poly[d(G-C)2] at the low R ratios. As the stacked species increased with an increasing R ratio, the six-coordinated species became the major bound species. These observations lead us to conclude that the guanine base' amino group plays a crucial role not only in determining the binding mode of VOTMPyP but also in the conversion of the six-coordinated species to the five-coordinated species.


Assuntos
DNA/química , Metaloporfirinas/química , Polidesoxirribonucleotídeos/química , Dicroísmo Circular , Poli dA-dT/química , Espectrofotometria , Espectrofotometria Ultravioleta
18.
J Clin Microbiol ; 41(7): 2952-60, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12843026

RESUMO

The nucleotide sequences (534 to 546 bp) of the groEL gene, which encodes the 60-kDa heat shock protein GroEL, from 15 rickettsial strains were determined and compared. In the phylogenetic tree created by the unweighted pair group method with arithmetic averages and the neighbor-joining method, rickettsial strains could be distinguished from Ehrlichia strains. Five spotted fever group strains, four typhus group strains, and six scrub typhus group (STG) strains were differentiated as distinct entities. Unlike gltA and ompA gene analyses, differentiation between members of the genus Rickettsia and the STG rickettsiae by groEL gene analysis was possible. In comparison with 16S rRNA gene analysis, the groEL gene has a higher degree of divergence among the rickettsiae. We therefore successfully developed rapid differentiation methods, PCR-restriction fragment length polymorphism analysis and a species-specific PCR, based on the groEL gene sequences. Four Korean isolates were identified by these methods and groEL gene analysis. The results suggest that the groEL gene is useful for the identification and characterization of rickettsiae.


Assuntos
Técnicas de Tipagem Bacteriana , Chaperonina 60/genética , Infecções por Rickettsia/microbiologia , Rickettsia/classificação , Análise de Sequência de DNA , DNA Ribossômico/análise , DNA Ribossômico/genética , Humanos , Coreia (Geográfico) , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Rickettsia/genética , Especificidade da Espécie
19.
Biophys J ; 83(6): 3460-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12496112

RESUMO

The retinal analog 13-desmethyl-13-iodoretinal (13-iodoretinal) was newly synthesized and incorporated into apomembranes to reconstitute bacteriorhodopsin analog 13-I-bR. The absorption maximum was 598 nm and 97% of the chromophore was an all-trans isomer in the dark- and light-adapted state. Upon flash illumination, 13-I-bR underwent a transient spectral change in which a shorter wavelength intermediate (lambda(max) = 426 nm) similar to the M species of the native bR developed. Also, 13-I-bR showed light-induced proton pumping with rates and extents comparable to those seen in the native bR. The ultraviolet circular dichroism (CD) spectrum originating from the aromatic groups was different from that of the native bR, indicating that the substituted bulky iodine atom strongly interacts with neighboring amino acids. A projection difference Fourier map showed the labeled iodine was in the vicinity of helix C. 13-I-bR is an advantageous specimen for kinetic investigations of light-induced structural changes associated with the proton pumping cycle by x-ray diffraction.


Assuntos
Bacteriorodopsinas/fisiologia , Bacteriorodopsinas/efeitos da radiação , Membrana Purpúrea/fisiologia , Retinaldeído/análogos & derivados , Retinaldeído/fisiologia , Bacteriorodopsinas/química , Simulação por Computador , Escuridão , Concentração de Íons de Hidrogênio/efeitos da radiação , Luz , Modelos Biológicos , Estimulação Luminosa , Fotoquímica/métodos , Fotólise/efeitos da radiação , Bombas de Próton/fisiologia , Bombas de Próton/efeitos da radiação , Membrana Purpúrea/efeitos da radiação , Retinaldeído/química , Retinaldeído/efeitos da radiação , Difração de Raios X/métodos
20.
Am J Chin Med ; 30(4): 463-70, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12568274

RESUMO

This study investigates changes in autonomic nervous function through Qi-training. The power spectrum of heart rate variability (HRV) was examined in 20 sedentary healthy subjects and 20 Qi-trainees. It was found that Qi-training in healthy young subjects during controlled respiration increases the high frequency (HF) power and decreases the low frequency/high frequency (LF/HF) power ratio of HRV. These results support the hypothesis that Qi-training increases cardiac parasympathetic tone. In addition, Qi-trainees were found to have higher parasympathetic heart modulation compared with their age-matched, sedentary counterparts. This augmented HRV in Qi-trainees provides further support for long-term Qi-training as a possible non-pharmacological cardio-protective maneuver. In conclusion, Qi-training may stabilize the autonomic nervous system by modulating the parasympathetic nervous system.


Assuntos
Exercícios Respiratórios , Frequência Cardíaca/fisiologia , Adulto , Eletrocardiografia , Feminino , Humanos , Coreia (Geográfico) , Masculino , Sistema Nervoso Parassimpático/fisiologia , Aptidão Física/fisiologia
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