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1.
AIDS Care ; 32(7): 829-834, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31426660

RESUMO

The aim of the study was to evaluate the oral environment and the taste function of Japanese HIV-infected patients treated with antiretroviral therapy. Their median age of 73 patients taking anti-HIV drugs was 46 years. The median period of taking anti-HIV drugs was 30 months. The oral condition was evaluated by measurement of oral moisture, amount of saliva secretion, the number of oral bacteria, presence of oral candida, a taste test, and the number of missing teeth. The levels of oral moisture and secreted saliva were significantly lower in the HIV-infected group than in the healthy volunteer (control) group. The HIV-infected group showed a more robust decrease in taste sensation than the control group. The number of missing teeth was significantly higher in the HIV-infected group than in the control group. Furthermore, all of the evaluated oral conditions were worse in the HIV-infected patients whose CD4+ T lymphocyte counts were less than 500/mm3 than in the control group. It became clear that the patients taking anti-HIV drugs, especially the CD4+ count < 500/mm3 group, had a deteriorated oral environment and dysgeusia, suggesting that the management of oral hygiene is necessary to maintain oral health, which leads to systemic health.


Assuntos
Infecções por HIV , Paladar , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Infecções por HIV/tratamento farmacológico , Humanos , Japão/epidemiologia , Pessoa de Meia-Idade
2.
Oral Dis ; 21(5): 626-33, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25703825

RESUMO

OBJECTIVE: A large number of individuals have halitosis. The total amount of volatile sulfur compounds, which are the main cause of halitosis, has been correlated with periodontitis following bacterial infection. In this study, Porphyromonas gingivalis (Pg), a major periodontopathogenic bacterium, was isolated from patients with halitosis by the amplification of 16S rRNA, and the ability of isolated Pg to produce methyl mercaptan (CH3 SH) was determined to clarify the relationship between halitosis and Pg infection. MATERIALS AND METHODS: CH3 SH concentrations were measured in patients using Oral Chroma. The production of CH3 SH by Pg standard and clinical strains was also measured in vitro. Real-time PCR was performed to compare the expression of mgl mRNA (which encoded l-methionine-a-deamino-g-mercaptomethane-lyase) among the Pg strains. The production of CH3 SH and the expression of mgl mRNA were also determined to assess the effects of oriental medicine. RESULTS: The production of CH3 SH and the expression of mgl mRNA strongly correlated with each other in the presence of l-methionine. The expression of mgl mRNA by Pg W83 was strongly inhibited by magnoliaceae. CONCLUSION: The production of CH3 SH was correlated with the expression of mgl. Furthermore, the oriental medicine, magnoliaceae, may represent a potential treatment for halitosis.


Assuntos
Halitose/microbiologia , Porphyromonas gingivalis/genética , Porphyromonas gingivalis/metabolismo , RNA Mensageiro/biossíntese , Compostos de Sulfidrila/metabolismo , Adulto , Idoso , Anti-Infecciosos/farmacologia , Proteínas de Bactérias/efeitos dos fármacos , Infecções por Bacteroidaceae/metabolismo , Infecções por Bacteroidaceae/microbiologia , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Humanos , Magnoliaceae , Masculino , Metionina/metabolismo , Metionina/farmacologia , Pessoa de Meia-Idade , Periodontite/metabolismo , Periodontite/microbiologia , Porphyromonas gingivalis/isolamento & purificação , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adulto Jovem
3.
Br J Dermatol ; 171(4): 722-31, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24725174

RESUMO

BACKGROUND: Mycosis fungoides (MF) classically presents from patch stage to plaque stage over a number of years and finally progresses to tumour stage with nodal or visceral involvement. The mechanism of progression remains incompletely elucidated. Chemokines and their receptors are known to be involved in disease mechanisms, with CXCL12 and CXCR4 playing a critical role in carcinogenesis, invasion and cancer cell migration in various carcinomas. OBJECTIVES: To investigate the expression of CXCL12 and CXCR4 in different cutaneous stages of MF. METHODS: Formalin-fixed, paraffin-embedded skin samples from 40 patients with MF (21 patch stage, 10 plaque stage, nine tumour stage) and 30 non-neoplastic control skin samples were analysed. CXCL12 and CXCR4 were assessed by quantitative reverse-transcription polymerase chain reaction and immunohistochemical staining. RESULTS: The expression level of mRNA for CXCL12 in plaque-stage MF was significantly higher than in control skin (P = 0.0035), or patch-stage (P = 0.0108) or tumour-stage disease (P = 0.0089). The CXCR4 mRNA expression level in plaque-stage disease was significantly higher than in control skin (P = 0.0090) or patch-stage disease (P = 0.0387). CXCL12- and CXCR4-positive cell rates in patch-stage and plaque-stage MF were significantly higher than those in control skin (P < 0.0001). CXCL12- and CXCR4-positive cell rates in tumour-stage MF were significantly lower than those in patch- and plaque-stage disease (P = 0.0274 and P = 0.0492, respectively). CONCLUSIONS: Our data suggest that neoplastic T cells in MF are exposed to the microenvironment, given the abundance of CXCL12 during its progression, and also that neoplastic T cells express CXCR4, especially in the pretumour stage. We reveal that the CXCL12-CXCR4 axis plays a critical role in MF progression.


Assuntos
Quimiocina CXCL12/metabolismo , Progressão da Doença , Micose Fungoide/metabolismo , Receptores CXCR4/metabolismo , Neoplasias Cutâneas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Imuno-Histoquímica , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/metabolismo , Linfócitos T/metabolismo
4.
J Phys Chem Lett ; 14(27): 6241-6247, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37401781

RESUMO

Solution-state nuclear magnetic resonance spectroscopy (NMR) is a powerful method for the analysis of intermolecular interactions within a biomolecular system. However, low sensitivity is one of the major obstacles of NMR. We improved the sensitivity of solution-state 13C NMR for the observation of intermolecular interactions between protein and ligand using hyperpolarized solution samples at room temperature. Eutectic crystals composed of 13C-salicylic acid and benzoic acid doped with pentacene were hyperpolarized by dynamic nuclear polarization using photoexcited triplet electrons, and a 13C nuclear polarization of 0.72 ± 0.07% was achieved after dissolution. The binding of human serum albumin and 13C-salicylate was observed with several hundred times sensitivity enhancement under mild conditions. The established 13C NMR was applied for pharmaceutical NMR experiments by observation of the partial return of the 13C chemical shift of salicylate by competitive binding with other non-isotope-labeled drugs.


Assuntos
Proteínas , Ácido Salicílico , Humanos , Ligantes , Solubilidade , Espectroscopia de Ressonância Magnética/métodos , Proteínas/química , Ressonância Magnética Nuclear Biomolecular/métodos
5.
Clin Nephrol ; 78(3): 224-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22874111

RESUMO

Fabry disease (FD) is an Xlinked disorder resulting in a deficiency in α-galactosidase A (α-Gal) activity. FD is one of the causes of progressive renal dysfunction, but its diagnosis is often delayed or missed completely. We herein report the case of a 70-year-old male who had been receiving hemodialysis (HD) for 23 y who was diagnosed with FD after his participation in a screening program for plasma α-Gal activity for 892 HD patients. He had a low plasma α-Gal activity level and was demonstrated to have an E66Q mutation in exon 2 of the α-Gal gene. One of his daughters had the same mutation. The proband died due to aspiration pneumonia before receiving enzyme replacement therapy. We reviewed previous studies and found E66Q mutation in 36% of Japanese FD patients on HD including the present case. The clinical characteristics of E66Q variant are also discussed.


Assuntos
Doença de Fabry/enzimologia , Doença de Fabry/genética , alfa-Galactosidase/genética , Idoso , Doença de Fabry/complicações , Humanos , Japão , Masculino , Mutação , Diálise Renal , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/terapia , alfa-Galactosidase/sangue
6.
J S Afr Vet Assoc ; 93(1): 16-24, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35950805

RESUMO

ABSTRACT: This study investigated causes of attenuation of cerebrospinal fluid (CSF) signal on heavily T2-weighted (T2W) images in dogs with thoracolumbar disc extrusion. Medical records and magnetic resonance images were retrospectively reviewed. Dogs were classified into the following grades; grade 1, non-ambulatory paraparesis; grade 2, paraplegia with deep pain perception and grade 3, paraplegia without deep pain perception. The length of intramedullary T2W hyperintensity of the spinal cord, cranial/ caudal expansion of extradural compressive materials (ECM), and the CSF signal attenuation were measured. Ratios to the second lumbar vertebra (L2) were calculated for the length of intramedullary T2W hyperintensity (T2W:L2), cranial/caudal expansion of ECM (ECML:L2), and CSF signal attenuation (CSF:L2). The dogs were classified into focal or extended T2W hyperintensity groups according to the length [focal, shorter than length of L2; extended, longer than L2]. The area of EMC and the spinal canal were measured on transverse images at the lesion deriving occupancy ratio. The correlation between CSF:L2 and other data were analysed, and CSF:L2 was compared between the grades. In dogs with intramedullary T2W hyperintensity, the locations of CSF attenuation and the hyperintensity were compared if those locations were matched. Fifty-five dogs were included, 36 of which showed intramedullary T2W hyperintensity. Twenty-two of 36 dogs were considered as match of the location of the CSF attenuation and hyperintensity. CSF:L2 was significantly correlated with T2W:L2 in dogs with extended T2W hyperintensity (p = 0.0002), while CSF:L2 was significantly correlated with ECML:L2 in dogs with focal or no T2W hyperintensity (p = 0.0103 and p = 0.0364, respectively). CSF:L2 in grade 3 was significantly greater than those in patients who were grade 1 or 2 (both p < 0.001). In conclusion, higher CSF:L2, which was frequently seen in grade 3, would be most consistent with a higher T2W:L2 which might indicate spinal cord swelling.


Assuntos
Doenças do Cão , Deslocamento do Disco Intervertebral , Disco Intervertebral , Animais , Doenças do Cão/cirurgia , Cães , Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/veterinária , Imageamento por Ressonância Magnética/veterinária , Paraplegia/diagnóstico por imagem , Paraplegia/patologia , Paraplegia/veterinária , Estudos Retrospectivos , Medula Espinal/patologia
7.
J Phys Chem B ; 126(19): 3530-3538, 2022 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-35538043

RESUMO

Dissolution dynamic nuclear polarization has been applied in various fields, including chemistry, biology, and medical science. To expand the scope of these applications, the nuclear singlet state, which is decoherence-free against dipolar relaxation between spin pairs, has been studied experimentally, theoretically, and numerically. The singlet state composed of proton spins is used in several applications, such as enhanced polarization preservation, molecular tagging to probe slow dynamic processes, and detection of ligand-protein complexes. In this study, we predict the lifetimes of the nuclear spin states composed of proton spin pairs using the molecular dynamics method and quantum chemistry simulations. We consider intramolecular dipolar, intermolecular dipolar between solvent and solute, chemical shift anisotropy, and spin-rotation interactions. In particular, the relaxation rate of intermolecular dipolar interactions is calculated using the molecular dynamics method for various solvents. The calculated values and the experimental values are of the same order of magnitude. Our program would provide insight into the molecular design of several NMR applications and would be helpful in predicting the nuclear spin relaxation time of synthetic molecules in advance.


Assuntos
Simulação de Dinâmica Molecular , Prótons , Espectroscopia de Ressonância Magnética/métodos , Soluções , Solventes
8.
Acta Gastroenterol Belg ; 84(2): 289-294, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34217177

RESUMO

BACKGROUND AND STUDY AIM: In principle, additional surgery is performed after endoscopic submucosal dissection for early gastric cancer if the vertical margin is positive, regardless of lesion damage. The recurrence rate of vertical margin-positive lesions due to lesion damage after endoscopic submucosal dissection is unknown, and unnecessary surgeries may be performed. In this study, we investigated whether there was a difference in the recurrence rate between vertical margin-positive lesions due to lesion damage and vertical margin-negative lesions. PATIENTS AND METHODS: We included 1,294 intramucosal gastric cancer lesions that were resected by endoscopic submucosal dissection between January 2008 and December 2016, without additional surgery. The lesions were divided into the Damage and No damage groups based on vertical margin status. The Damage group had only one non-curative indication: a positive vertical margin due to lesion damage. The No damage group had no non curative indications. We compared the recurrence rate between the Damage and No damage groups. RESULTS: The recurrence rates of the Damage and No damage groups were 0% (0/23; 95% confidence interval: 0-14.8%) and 0% (0/1,271; 95% confidence interval: 0-0.003%), respectively, with no statistically significant difference. CONCLUSIONS: In intramucosal gastric cancer, the recurrence rate of vertical margin-positive lesions due to lesion damage was 0%, which did not differ from that of vertical margin-negative lesions with curative resection. Follow-up, instead of additional surgery, may be an option for patients with non-curative resection when the only non-curative indication is a positive vertical margin due to lesion damage.


Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Gástricas , Mucosa Gástrica , Humanos , Recidiva Local de Neoplasia , Estudos Retrospectivos , Resultado do Tratamento
9.
J Exp Med ; 141(6): 1308-28, 1975 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-47899

RESUMO

Treatment of a p-azobenzoate (PAB) derivative of a copolymer of D-glutamic acid and D-lysine (D-GL) induced a profound state of unresponsiveness to PAB-reactive helper T lymphocytes generated in PAB-mouse gamma globulin (MGG)-primed mice. This unresponsiveness in T lymphocytes was specific for PAB-reactive cells, since the bacterial alpha-amylase-, keyhole limpet hemocyanin-, or ovalbumin-primed helper T lymphocytes were not suppressed by PAB-D-GL treatment. Taking advantage of the relative ease with which PAB-D-GL can induce specific unresponsiveness to helper T lymphocytes in an animal previously primed with PAB-MGG, it was possible to approach certain questions concerning the mechanisms of tolerance-induction and the fate of tolerant helper T lymphocytes in the PAB-D-GL model by utilizing a classical adoptive cell transfer systemmelimination of the possibility of carry-over of the tolerogen with cells or of the generation of suppressor cells as the result of PAB-D-GL treatment as an explanation of the suppression of helper T-cell activity strongly inplicates the existence of a central intracellular mechanism of specific tolerance on the helper T-cell level. The possibility that suppression of the activity of PAB-reactive helper T lymphocytes by PAB-D-GL reflects simple blocking of surface receptor molecules on T lymphocytes was ruled out as it was found that the helper activity of PAB-reactive cells was minimally suppressed even when PAB-D-GL was directly exposed in vitro to helper T lymphocytesmmoreover, the most conclusive evidence on te the tolerant state induced by in vivo exposure of primed T cells to PAB-D-GL. It appears, therefore, that specific tolerance induced by PAB-D-GL' TO PAB-reactive helper T lymphocytes is an example of irreversible inhibition of T-cell reactivity to antigen, reflecting yet to be determined events at the intra- and subcellular levels.


Assuntos
Proteínas de Transporte/imunologia , Haptenos , Tolerância Imunológica , Linfócitos T/imunologia , Amilases/imunologia , Animais , Formação de Anticorpos , Células Produtoras de Anticorpos/imunologia , Compostos Azo/imunologia , Benzoatos/imunologia , Sítios de Ligação de Anticorpos , Membrana Celular/imunologia , Proteínas do Sistema Complemento/metabolismo , Adjuvante de Freund , Glutamatos , Hemocianinas/imunologia , Soros Imunes , Esquemas de Imunização , Imunização Passiva/métodos , Lisina/imunologia , Camundongos , Peptídeos/imunologia , Tripsina/farmacologia , gama-Globulinas
10.
J Exp Med ; 146(1): 74-90, 1977 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-68994

RESUMO

Helper and suppressor T-cell activities were detected simultaneously in the spleen cells of mice immunized with para-azobenzoate (PAB)-mouse gammaglobulin (MGG). Dinitrophenyl (DNP)-specific B cells were raised by immunization with DNP-keyhole limpet hemocyanin (KLH) and used as the indicator B-cell population. The helper and suppressor T-cell activities were determined after adoptively transferring spleen cells from PAB-MGG- primed donors and DNP-KLH-primed donors into X-irradiated recipients. Stimulation of these recipients with DNP-MGG-PAB detected helper T-cell activity, which was measured in terms of increased anti-DNP antibody responses of DNP-KLH-primed cells over these responses in the presence of unprimed cells. On the other hand, when DNP-KLH-primed cells were stimulated with DNP-KLH-PAB in the presence of PAB-MGG-primed cells, anti-DNP antibody responses were substantially lower than in unprimed normal cells. This suppressor cell population was (a) hapten-reactive, (b) present in B-cell-depleted spleen cells, (c) Thy-1 positive, (d) detectable earlier than the helper T-cell activities after priming (e) more radiosensitive than helper cells, and (f) found in the spleen but not the lymph nodes in contrast to helper T cells. These data indicate that these suppressor T cells are distinct from the helper T cells. PAB-reactive T cells clearly suppressed the antibody response by inhibiting KLH-reactive helper T-cell functions. The hapten-reactive T-lymphocyte system described here should be useful for analyzing and manipulating the immune response and for studying regulatory interactions of helper and suppressor T cells in the induction of antibody responses.


Assuntos
Haptenos , Supressão Genética , Linfócitos T/imunologia , Animais , Formação de Anticorpos , Células Produtoras de Anticorpos/imunologia , Reações Antígeno-Anticorpo , Compostos Azo/imunologia , Linfócitos B/imunologia , Benzoatos/imunologia , Dinitrofenóis/imunologia , Haplorrinos , Hemocianinas/imunologia , Técnica de Placa Hemolítica , Humanos , Imunização , Linfonodos/imunologia , Camundongos , Baço/citologia , gama-Globulinas/imunologia
11.
J Exp Med ; 146(1): 91-106, 1977 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-68995

RESUMO

An experimental condition was established in vivo for selectively eliminating hapten-reactive suppressor T-cell activity generated in mice primed with a para-azobenzoate (PAB)-mouse gamma globulin (MGG)-conjugate and treated with PAB-nonimmunogenic copolymer of D-amino acids (D- glutamic acid and D-lysine; D-GL). The elimination of suppressor T-cell activity with PAB-D-GL treatment from the mixed populations of hapten- reactive suppressor and helper T cells substantially increased apparent helper T-cell activity. Moreover, the inhibition of PAB-reactive suppressor T-cell generation by the pretreatment with PAB-D-GL before the PAB-MGG-priming increased the development of PAB-reactive helper T-cell activity. The analysis of hapten-specificity of helper T cells revealed that the reactivity of helper cells developed in the absence of suppressor T cells was more specific for primed PAB-determinants and their cross-reactivities to structurally related determinants such as meta-azobenzoate (MAB) significantly decreased, as compared with the helper T-cell population developed in the presence of suppressor T lymphocytes. In addition, those helper T cells generated in the absence of suppressor T cells were highly susceptible to tolerogenesis by PAB-D- GL. Similarly, the elimination of suppressor T lymphocytes also enhanced helper T-cell activity in a polyclonal fashion in the T-T cell interactions between benzylpenicilloyl (BPO)-reactive T cells and PAB- reactive T cells after immunization of mice with BPO-MGG-PAB. Thus inhibition of BPO-reactive suppressor T-cell development by the BPO-v-GL- pretreatment resulted in augmented generation of PAB-reactive helper T cells with higher susceptibility of tolerogenesis to PAB-D-GL. Thus, these results support the notion that suppressor T cells eventually suppress helper T-cell activity and indicate that the function of suppressor T cells related to helper T-cell development is to inhibit the increase in the specificity and apparent affinity of helper T cells in the primary immune response. The hapten-reactive suppressor and helper T lymphocytes are considered as a model system of T cells that regulate the immune response, and the potential applicability of this system to manipulating various T cell-mediated immune responses is discussed in this context.


Assuntos
Células Produtoras de Anticorpos/imunologia , Haptenos , Supressão Genética , Linfócitos T/imunologia , Animais , Formação de Anticorpos , Reações Antígeno-Anticorpo , Compostos Azo/imunologia , Benzoatos/imunologia , Dinitrofenóis/imunologia , Glutamatos/imunologia , Hemocianinas/imunologia , Técnica de Placa Hemolítica , Tolerância Imunológica , Imunização , Lisina/imunologia , Camundongos , Penicilina G/análogos & derivados , Penicilina G/imunologia , gama-Globulinas/imunologia
12.
J Exp Med ; 149(1): 185-99, 1979 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-310858

RESUMO

2,4.6-trinitrophenyl (TNP)-reactive T-cell activities were raised in mice by immunization with TNP-isologous mouse gamma globulin. After establishing that TNP-reactive T lymphocytes can serve as amplifier cells for induction of killer T lymphocytes in allogeneic system, we explored the possibility of this hapten-reactive T-cell system to amplify tumor-specific killer T-lymphocyte activity in the syngeneic system. We utlized relatively weak immunogenic syngeneic plasmacytoma X5563 in C3H/He mice. Analysis of the TNP-reactive T-cell activities revealed that such T lymphocytes express the biological functions of both major subtypes of regulatory T cells, namely suppressors and helpers, and that TNP-reactive suppressor and helper T lymphocytes, respectively, differ in their relative susceptibility to specific inactivation by TNP conjugates of the nonimmunogenic D-amino acid copolymer, D-glutamic acid, and D-lysine (D-GL). By taking advantage of the relative susceptibility-difference to TNP-D-GL, selective inactivation of TNP-reactive suppressor T cells was induced by appropriate treatment with TNP-D-GL, and the generation of TNP-reactive helper T-cell activity was amplified. The supplement of augmented TNP-reactive helper T-cell activity to the system at the immunization with syngeneic X5563 with TNP-haptenation, resulted in a striking augmentation of induction of tumor-specific killer T-lymphocyte activity, and a considerable number of hosts survived after the challenge with lethal dose of viable tumor cells. Thus, appropriate manipulations designed to induce potent hapten-reactive helper T-lymphocytes provided the potential for a very effective mode of immunoprophylaxis against tumor.


Assuntos
Antígenos de Neoplasias , Citotoxicidade Imunológica , Terapia de Imunossupressão , Cooperação Linfocítica , Neoplasias Experimentais/imunologia , Linfócitos T/imunologia , Animais , Proteínas de Transporte/imunologia , Feminino , Haptenos , Memória Imunológica/efeitos da radiação , Células Matadoras Naturais/imunologia , Cooperação Linfocítica/efeitos da radiação , Masculino , Camundongos , Plasmocitoma/imunologia , Raios X
13.
J Chem Phys ; 133(15): 154504, 2010 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-20969400

RESUMO

In dynamic nuclear polarization (DNP) experiments applied to organic solids for creating nonequilibrium, high (1)H spin polarization, an efficient buildup of (1)H polarization is attained by partially deuterating the material of interest with an appropriate (1)H concentration. In such a dilute (1)H spin system, it is shown that the (1)H spin diffusion rate and thereby the buildup efficiency of (1)H polarization can further be enhanced by continually applying radiofrequency irradiation for deuterium decoupling during the DNP process. As experimentally confirmed in this work, the electron spin polarization of the photoexcited triplet state is mainly transferred only to those (1)H spins, which are in the vicinity of the electron spins, and (1)H spin diffusion transports the localized (1)H polarization over the whole sample volume. The (1)H spin diffusion coefficients are estimated from DNP repetition interval dependence of the initial buildup rate of (1)H polarization, and the result indicates that the spin diffusion coefficient is enhanced by a factor of 2 compared to that without (2)H decoupling.

14.
Rev Sci Instrum ; 91(1): 015107, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012590

RESUMO

A magnetic quadrupole lens system coupled to a 30° bending deflection magnet was designed and constructed to realize a beam focusing of Xe+ ions with the energy less than 200 eV. Compared to a triplet electrostatic quadrupole lens system, the quadrupole doublet magnetic lens system showed a larger beam transmission, indicating the mitigation of the space charge in the beam transport region free of the electrostatic field. The misalignment of the magnetic field axis was observed probably due to a slow change in magnetization of magnetic materials to construct the magnetic circuit of the quadrupole lens. A countermeasure to realign the beam axis by coupling the permanent magnets to trim coil electromagnets is proposed.

15.
Science ; 259(5097): 971-4, 1993 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-8438157

RESUMO

Interferon regulatory factor-1 (IRF-1), a transcriptional activator, and IRF-2, its antagonistic repressor, have been identified as regulators of type I interferon and interferon-inducible genes. The IRF-1 gene is itself interferon-inducible and hence may be one of the target genes critical for interferon action. When the IRF-2 gene was overexpressed in NIH 3T3 cells, the cells became transformed and displayed enhanced tumorigenicity in nude mice. This transformed phenotype was reversed by concomitant overexpression of the IRF-1 gene. Thus, restrained cell growth depends on a balance between these two mutually antagonistic transcription factors.


Assuntos
Transformação Celular Neoplásica/genética , Proteínas de Ligação a DNA/genética , Expressão Gênica , Fosfoproteínas/genética , Proteínas Repressoras , Fatores de Transcrição , Células 3T3/metabolismo , Animais , Northern Blotting , Mapeamento Cromossômico , Cromossomos Humanos Par 5 , DNA/biossíntese , Humanos , Técnicas de Imunoadsorção , Fator Regulador 1 de Interferon , Fator Regulador 2 de Interferon , Camundongos , Camundongos Nus , Fenótipo , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Transfecção
16.
Science ; 272(5262): 719-22, 1996 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-8614832

RESUMO

Signal transducers and activators of transcription (STAT) proteins can be conditionally activated in response to epidermal growth factor (EGF) and interferon (IFN)-gamma. STAT activation was correlated with cell growth inhibition in response to EGF and IFN-gamma. Activated STAT proteins specifically recognized the conserved STAT-responsive elements in the promoter of the gene encoding the cyclin-dependent kinase (CDK) inhibitor p21 WAF1/CIP1 and regulated the induction of p21 messenger RNA. IFN-gamma did not inhibit the growth of U3A cells, which are deficient in STAT1, but did inhibit the growth of U3A cells into which STAT1 alpha was reintroduced. Thus, STAT1 protein is essential for cell growth suppression in response to IFN-gamma. The STAT signaling pathway appears to negatively regulate the cell cycle by inducing CDK inhibitors in response to cytokines.


Assuntos
Divisão Celular , Ciclinas/genética , Proteínas de Ligação a DNA/fisiologia , Regulação da Expressão Gênica , Transdução de Sinais , Transativadores/fisiologia , Sequência de Bases , Sítios de Ligação , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/biossíntese , DNA/biossíntese , Proteínas de Ligação a DNA/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Humanos , Interferon gama/farmacologia , Dados de Sequência Molecular , Regiões Promotoras Genéticas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição STAT1 , Fator de Transcrição STAT3 , Transativadores/metabolismo , Transfecção , Células Tumorais Cultivadas
17.
Science ; 264(5167): 1921-4, 1994 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-8009222

RESUMO

The mechanisms underlying interferon (IFN)-induced antiviral states are not well understood. Interferon regulatory factor-1 (IRF-1) is an IFN-inducible transcriptional activator, whereas IRF-2 suppresses IRF-1 action. The inhibition of encephalomyocarditis virus (EMCV) replication by IFN-alpha and especially by IFN-gamma was impaired in cells from mice with a null mutation in the IRF-1 gene (IRF-1-/- mice). The IRF-1-/- mice were less resistant than normal mice to EMCV infection, as revealed by accelerated mortality and a larger virus titer in target organs. The absence of IRF-1 did not clearly affect replication of two other types of viruses. Thus, IRF-1 is necessary for the antiviral action of IFNs against some viruses, but IFNs activate multiple activation pathways through diverse target genes to induce the antiviral state.


Assuntos
Infecções por Cardiovirus/imunologia , Proteínas de Ligação a DNA/fisiologia , Interferon-alfa/farmacologia , Interferon gama/farmacologia , Fosfoproteínas/fisiologia , Fatores de Transcrição/fisiologia , Replicação Viral , Animais , Infecções por Cardiovirus/microbiologia , Células Cultivadas , Proteínas de Ligação a DNA/genética , Vírus da Encefalomiocardite/fisiologia , Regulação da Expressão Gênica , Fator Regulador 1 de Interferon , Camundongos , Mutação , Fosfoproteínas/genética , Simplexvirus/fisiologia , Fatores de Transcrição/genética , Vírus da Estomatite Vesicular Indiana/fisiologia
18.
J S Afr Vet Assoc ; 80(4): 254-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20458868

RESUMO

An 11-year-old male Rough collie was submitted with paraparesis, but did not respond to medical treatment. Clinical signs worsened and the dog displayed paralysis, inability to stand and loss of voluntary bladder control, whereupon magnetic resonance imaging (MRI) was performed. No significant abnormalities were identified from MRI, blood tests, cerebrospinal fluid tests or radiography. After MRI, the dog developed dyspnoea and died. Autopsy and subsequent histopathological examination led to a diagnosis of degenerative myelopathy.


Assuntos
Doenças do Cão/diagnóstico , Coxeadura Animal/etiologia , Imageamento por Ressonância Magnética/veterinária , Doenças Neurodegenerativas/veterinária , Doenças da Medula Espinal/veterinária , Animais , Diagnóstico Diferencial , Cães , Evolução Fatal , Masculino , Doenças Neurodegenerativas/diagnóstico , Doenças da Medula Espinal/diagnóstico
19.
J Periodontol ; 79(10): 1984-90, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18834255

RESUMO

BACKGROUND: The purpose of this study was to investigate the effects of low-intensity pulsed ultrasound (LIPUS) stimulation on the proliferation and differentiation of cementoblast lineage cells. METHODS: An immortalized human periodontal ligament cell line (HPL) showing immature cementoblastic differentiation was used. Cultured HPL cells were subjected to LIPUS exposure (frequency = 1 MHz; pulsed 1:4; intensity = 30 mW/cm(2)) or sham exposure for 15 minutes per day. Expression levels of alkaline phosphatase (ALP), type I collagen (Col-I), runt-related gene 2 (Runx2), bone sialoprotein (BSP), osteocalcin (OCN), and osteopontin (OPN) mRNA were analyzed with real-time polymerase chain reaction analysis. Furthermore, ALP activity, collagen synthesis, and protein level of Runx2 were examined after 6 days of LIPUS exposure. RESULTS: mRNA and protein levels of ALP, Col-I, and Runx2 were significantly increased by LIPUS exposure compared to controls, whereas BSP, OCN, and OPN mRNA expression could not be detected in HPL cells, irrespective of LIPUS exposure. CONCLUSION: LIPUS enhanced ALP activity, collagen synthesis, and Runx2 expression of HPL cells, which provides important insight into the promotion of early cementoblastic differentiation of immature cementoblasts.


Assuntos
Cemento Dentário/citologia , Ultrassom , Fosfatase Alcalina/análise , Biomarcadores/análise , Western Blotting , Diferenciação Celular , Linhagem Celular , Linhagem da Célula , Proliferação de Células , Células Cultivadas , Colágeno/biossíntese , Colágeno Tipo I/análise , Subunidade alfa 1 de Fator de Ligação ao Core/análise , Humanos , Sialoproteína de Ligação à Integrina , Osteocalcina/análise , Osteopontina/análise , Ligamento Periodontal/citologia , Reação em Cadeia da Polimerase , RNA/análise , Sialoglicoproteínas/análise
20.
Anim Reprod Sci ; 106(3-4): 421-30, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17644281

RESUMO

Supplementing in vitro maturation medium with porcine follicular fluid (FF) improves maturation rate, male pronucleus formation, and monospermic fertilization of pig oocytes. This study examined, (1) if there are differences in FF derived from large follicles (LF, 5-6mm in diameter) and small follicles (SF, 3-4mm in diameter) on the effect of supplementing the maturation medium with FF on the progression of nuclear maturation, fertilization rate, and developmental competence of porcine oocytes; (2) whether the FF source influences the effect of the FF on the maturation medium on the survival rate and proliferation rate of cumulus cells (CCs) and the expansion of cumulus-oocyte-complexes (COCs); (3) whether the oocyte source (oocytes collected from LFs or SFs) influences the effect of FF on the progression of the nuclear maturation of oocytes; (4) whether the factors in the FF that affect the kinetics of nuclear maturation are proteins, and the range of the molecular weight of the FF factors. In experiment 1, adding FF from LFs (LFF) significantly accelerated nuclear maturation and improved the fertilization rate; the developmental ratio was comparable with those of adding FF from SFs (SFF). In experiment 2, adding LFF, but not SFF, improved the CC survival rate, although the FF source did not affect the proliferation rate. Expansion of COCs was greater with SFF than LFF. In experiment 3, LFF promoted nuclear maturation of oocytes collected from only LFs. There was a significant interaction between the FF source and the oocyte source in the effect on nuclear maturation stages at 36 h of maturation. In experiment 4, treatment of FF with heat or trypsin diminished the difference between the effect of LFF and SFF on the progression of nuclear maturation. In addition, the predominant effect of LFF compared to that of SFF on nuclear maturation was not affected by ultrafiltration of the FF with a 30-kDa filter, but was diminished by ultrafiltration with a 100-kDa filter. The present study suggests that some proteins present in LFF that range in molecular weight from 30 to 100 kDa improve the developmental competence of oocytes probably via progression of nuclear maturation and cumulus cells viability.


Assuntos
Núcleo Celular/efeitos dos fármacos , Líquido Folicular/fisiologia , Oócitos/efeitos dos fármacos , Oogênese/efeitos dos fármacos , Folículo Ovariano/citologia , Suínos/fisiologia , Animais , Técnicas de Cultura de Células , Núcleo Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura/farmacologia , Feminino , Oócitos/fisiologia , Oogênese/fisiologia , Folículo Ovariano/química , Folículo Ovariano/fisiologia
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