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1.
Malays J Pathol ; 42(3): 445-448, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33361727

RESUMO

The author reports two cases of Bullous pemphigoid (BP) with neurofibroma (NF)-like histopathological change. The two patients without neurofibromatosis type 1 (NF1) presented with several bullae on their trunk. Based on the results of positivity for anti-BP180 antibody, direct immunofluorescence, and histopathological findings, they were diagnosed with BP. Histologically, another lesion in the dermis, which was composed of spindle cells with wavy nuclei, collagen fibers, and mast cells, was located close to the bulla. Immunohistochemically, the spindle cells were diffusely positive for S-100 protein and CD34, and weakly positive for epithelial membrane antigen in certain foci. These findings were considered to be "NF-like" histopathological change. This is the first two cases of BP with NF-like histopathological change in patients without NF1.


Assuntos
Penfigoide Bolhoso/patologia , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Neurofibroma/patologia
2.
Andrologia ; 50(1)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28224697

RESUMO

Diabetes mellitus (DM) affects the male ejaculatory function. This study was designed to evaluate the role of oxidative stress in the development of diabetes-induced dysfunction of vas deferens (VD) in the rat. DM was induced by streptozotocin in 40 male Wistar rats. Subsequently, the diabetic animals were divided into three groups: DM group, DM + Eda group and DM + Tau group. These groups were administered saline, edaravone and taurine, respectively, daily for 4 weeks. Another group of ten rats served as a control group. DM was diagnosed in the 40 streptozotocin-injected rats. DM significantly reduced the VD weight. Additionally, DM induced in vitro VD hypercontractility, VD histological abnormalities and increased the serum and VD tissue concentration of malondialdehyde. VD immunohistochemistry revealed overexpression of three markers of oxidative stress. DM significantly reduced serum testosterone levels. No live birth was documented in all DM rats in mating experiments. Antioxidants significantly improved all the aforementioned parameters, except the testosterone levels. This study indicates a deleterious impact of DM-induced oxidative stress on VD histological and functional features. Antioxidant treatment may provide an adjunct tool to alleviate ejaculatory disorders for male patients with type 1 diabetes.


Assuntos
Antioxidantes/farmacologia , Diabetes Mellitus Experimental/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Ducto Deferente/efeitos dos fármacos , Animais , Antipirina/análogos & derivados , Antipirina/farmacologia , Diabetes Mellitus Experimental/metabolismo , Edaravone , Masculino , Malondialdeído/metabolismo , Ratos , Ratos Wistar , Taurina/farmacologia , Ducto Deferente/fisiopatologia
3.
J Eur Acad Dermatol Venereol ; 27(5): 589-92, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22364152

RESUMO

BACKGROUND: Extramammary Paget's disease (EMPD) is a distinct form of malignant skin neoplasm. Invasive EMPD is relatively rare and its detailed histopathological features have not been investigated to date. METHODS: Surgical specimens were obtained from 51 patients with primary invasive EMPD. Clinical data including lymph node status were retrieved from the patients' medical records. Cases were divided into subgroups according to invasion depth: dermal invasion ≤ 1 mm (minimal invasion) and dermal invasion > 1 mm in depth. Histological patterns (nodular/glandular pattern or micronodular pattern), lymphatic/venous invasion, mitosis and lymph node status were compared between the two groups. RESULTS: The invasive EMPDs included 26 cases (51.0%) with dermal invasion ≤ 1 mm (minimal invasion) and 25 cases (49.0%) with dermal invasion > 1 mm in depth. Lymph node metastasis was detected in 2/26 (7.7%) patients with minimally invasive EMPD. Nodular/glandular pattern (72.0%), lymphatic/venous invasion (52.0%), mitosis (88.0%) and nodal metastasis (88.0%) were all significantly more frequent in cases with dermal invasion > 1 mm, compared to EMPDs with dermal invasion ≤ 1 mm (minimal invasion) (P < 0.001). CONCLUSION: These results suggest that invasive EMPD can be divided according to invasion depth, with a cut-off depth of 1 mm. This might represent the basis for a useful, EMPD-specific staging system.


Assuntos
Doença de Paget Extramamária/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Auditoria Médica , Pessoa de Meia-Idade
4.
J Oral Rehabil ; 40(8): 582-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23692649

RESUMO

The oral appliance (OA) is considered to be an effective treatment modality for obstructive sleep apnoea (OSA). Upper airway enlargement during OA therapy is critical, and lateral cephalometry has been used for the two-dimensional evaluation of upper airway form during this therapy. However, this method cannot provide an accurate three-dimensional (3D) view of upper airway form. To confirm the effects of OA on the upper airway in patients with OSAS, we performed CT in the presence and absence of OA in 15 Japanese patients (12 males, 3 females) who responded to OA therapy. CT in the presence and absence of OA was consecutively performed for each patient, and upper airway cross-sectional area in six arbitrary planes parallel to the palatal plane was measured. Next, 3D image reconstruction was performed; morphological changes in upper airway form were evaluated, and upper airway volume at three levels from the palatal plane to the deepest point of the epiglottis was measured. The cross-sectional area of two planes in the posterior soft palate region significantly increased in the presence of OA compared with that in the absence of OA. In the presence of OA, upper airway cross-sectional area and volume significantly increased in the posterior soft palate region compared with those in the posterior tongue region. 3D CT image reconstruction accurately confirmed morphological changes in the upper airway during OA therapy. Continued use of this 3D evaluation is expected to improve the results of OA therapy in the future.


Assuntos
Imageamento Tridimensional/métodos , Palato/diagnóstico por imagem , Sistema Respiratório/diagnóstico por imagem , Apneia Obstrutiva do Sono/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Cefalometria/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Apneia Obstrutiva do Sono/terapia , Resultado do Tratamento
5.
Osteoarthritis Cartilage ; 20(11): 1383-90, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22846714

RESUMO

OBJECTIVE: Previous studies have shown that meniscectomy results in an increase of local load transmission and may cause degeneration of the knee cartilage. Using 3D reconstructed T2 mapping, we examined the influence on the femoral cartilage under loading after medial meniscectomy. DESIGN: Ten porcine knees were imaged using a pressure device and a 3.0-T magnetic resonance imaging (MRI) system. Consecutive sagittal T2 maps were obtained in neutral alignment with and without compression, and under compression at 10° varus alignment. After medial meniscectomy, the aforementioned MRI was repeated. Cartilage T2 before and after meniscectomy under each condition were compared at the 12 regions of interest (ROIs) defined on the 3D weight-bearing area of the femoral cartilage. RESULTS: Before meniscectomy, large decreases in T2 under neutral compression were mainly seen at the anterior and central ROIs of the medial cartilage, which shifted to the posterior ROIs after meniscectomy. There were significant differences in decrease in T2 ratio with loading before and after meniscectomy (9.8%/4.3% at the anterior zone, 4.0%/11.4% at the posterior zone, P < 0.05). By applying varus compression, a more remarkable decrease in the cartilage T2 in posterior ROIs after meniscectomy was achieved. (Before/after meniscectomy: 8.7%/2.5% at the anterior zone, 7.2%/18.7% at the posterior zone, P < 0.05). CONCLUSIONS: Assuming a decrease in T2 with loading correlated with the applied pressure, a deficiency of the medial meniscus resulted in a shift of the primary area with a maximal decrease of cartilage T2 with loading posteriorly in the porcine knee joint, presumably reflecting the intraarticular environment of load transmission.


Assuntos
Artroscopia/efeitos adversos , Cartilagem Articular/patologia , Meniscos Tibiais/cirurgia , Joelho de Quadrúpedes/patologia , Animais , Cartilagem Articular/fisiopatologia , Modelos Animais de Doenças , Imageamento por Ressonância Magnética , Meniscos Tibiais/fisiopatologia , Joelho de Quadrúpedes/fisiopatologia , Joelho de Quadrúpedes/cirurgia , Suínos , Suporte de Carga
6.
Osteoarthritis Cartilage ; 20(7): 646-52, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22469852

RESUMO

OBJECTIVE: The purpose of this study was to examine the three-dimensional (3D) progression patterns of early acetabular cartilage damage in hip dysplasia using high-resolutional computed tomography (CT) arthrography. DESIGN: Thirty-two dysplastic hips of 26 Japanese symptomatic females including 21 hips in pre-stage of osteoarthritis (Kellgren-Lawrence (K-L) grade 0; mean patient age, 32.0 years) and 11 hips in early stage of osteoarthritis (K-L grade 1 or 2; mean patient age, 32.8 years) were examined. Isotropic high-resolutional CT arthrography with an image resolution of 0.5 mm in any orthogonal direction was performed. A 3D acetabular cartilage model was generated and we evaluated distribution of cartilage thickness in 12 zones after dividing the weight-bearing area of the hip joint in radial and lateral/medial directions. RESULTS: In pre-stage of osteoarthritis, significant differences in cartilage thickness were observed between the lateral and medial zones in all radial regions, most prominently in the antero-superior region. In early stage of osteoarthritis, no significant differences in cartilage thickness were observed, except in the most posterior region. The lateral-medial (LM) ratio was defined as cartilage thickness in the lateral zone divided by that in the medial zone, and hips with the LM ratio in the antero-superior region of <1.4 had significantly more extensive involvement of labral tears than hips with the LM ratio of ≥1.4. CONCLUSIONS: In hip dysplasia, acetabular cartilage damage was probably occurred in the antero-superior lateral area. The LM ratio may be a sensitive index to quantify early cartilage damage associated with extent of labral disorders.


Assuntos
Acetábulo/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Luxação Congênita de Quadril/complicações , Osteoartrite do Quadril/etiologia , Acetábulo/patologia , Adolescente , Adulto , Artrografia/métodos , Cartilagem Articular/patologia , Diagnóstico Precoce , Luxação Congênita de Quadril/diagnóstico por imagem , Luxação Congênita de Quadril/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Pessoa de Meia-Idade , Osteoartrite do Quadril/diagnóstico por imagem , Osteoartrite do Quadril/patologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
8.
Osteoarthritis Cartilage ; 18(7): 902-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20472084

RESUMO

OBJECTIVE: Physiological magnetic resonance imaging (MRI) under loading or knee malalignment conditions has not been thoroughly investigated. We assessed the influence of static loading and knee alignment on T2 (transverse relaxation time) mapping of the knee femoral cartilage of porcine knee joints using a non-metallic pressure device. METHODS: Ten porcine knee joints were harvested en bloc with intact capsules and surrounding muscles and imaged using a custom-made pressure device and 3.0-T MRI system. Sagittal T2 maps were obtained (1) at knee neutral alignment without external loading (no loading), (2) under mechanical compression of 140 N (neutral loading), and (3) under the same loading conditions as in (2) with the knee at 10 degrees varus alignment (varus loading). T2 values of deep, intermediate, and superficial zones of the medial and lateral femoral cartilages at the weight-bearing area were compared among these conditions using custom-made software. Cartilage contact pressure between the femoral and tibial cartilages, measured by a pressure-sensitive film, was correlated with cartilage T2 measurements. RESULTS: In the medial cartilage, mean T2 values of the deep, intermediate, and superficial zones decreased by 1.4%, 13.0%, and 6.0% under neutral loading. They further decreased by 4.3%, 19.3%, and 17.2% under varus loading compared to no loading. In the lateral cartilage, these mean T2 values decreased by 3.9%, 7.7%, and 4.2% under neutral loading, but increased by 1.6%, 9.6%, and 7.2% under varus loading. There was a significant decrease in T2 values in the intermediate zone of the medial cartilage under both neutral and varus loading, and in the superficial zone of the medial cartilage under varus loading (P<0.05). Total contact pressure values under neutral loading and varus loading conditions significantly correlated with T2 values in the superficial and intermediate zones of the medial cartilages. CONCLUSIONS: The response of T2 to change in static loading or alignment varied between the medial and lateral cartilages, and among the deep, intermediate, and superficial zones. These T2 changes were significantly related to the contact pressure measurements. Our results indicate that T2 mapping under loading allows non-invasive, biomechanical assessment of site-specific stress distribution in the cartilage.


Assuntos
Cartilagem Articular/fisiologia , Articulação do Joelho/fisiologia , Suporte de Carga/fisiologia , Animais , Fenômenos Biomecânicos , Cartilagem Articular/anatomia & histologia , Articulação do Joelho/anatomia & histologia , Imageamento por Ressonância Magnética , Estatística como Assunto , Estresse Mecânico , Suínos
9.
Science ; 234(4773): 187-9, 1986 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-17746478

RESUMO

An orbiting spacecraft and ground observatories have been used to obtain interferometric observations of cosmic radio sources. The Tracking and Data Relay Satellite System (TDRSS) was used as the orbiting observatory in conjunction with two 64- meter radio telescopes at ground observatories, one in Australia and one in Japan. The quasars 1730-130 (NRAO 530), 1510-089, and 1741-038 were observed at a frequency of 2.3 gigahertz, and a maximum projected baseline of 1.4 earth diameters was achieved. All quasar observations for which valid data were acquired resulted in detected fringes. Many of the techniques proposed for a dedicated very long baseline interferometry observatory in space were used successfully in this experiment.

10.
Curr Biol ; 8(2): 121-4, 1998 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9427648

RESUMO

The yeast UBC9 gene encodes a protein with homology to the E2 ubiquitin-conjugating enzymes that mediate the attachment of ubiquitin to substrate proteins [1]. Depletion of Ubc9p arrests cells in G2 or early M phase and stabilizes B-type cyclins [1]. p18(Ubc9), the Xenopus homolog of Ubc9p, associates specifically with p88(RanGAP1) and p340(RanBP2) [2]. Ran-binding protein 2 (p340(RanBP2)) is a nuclear pore protein [3] [4], and p88(RanGAP1) is a modified form of RanGAP1, a GTPase-activating protein for the small GTPase Ran [2]. It has recently been shown that mammalian RanGAP1 can be conjugated with SUMO-1, a small ubiquitin-related modifier [5-7], and that SUMO-1 conjugation promotes RanGAP1's interaction with RanBP2 [2,5,6]. Here we show that p18(Ubc9) acts as an E2-like enzyme for SUMO-1 conjugation, but not for ubiquitin conjugation. This suggests that the SUMO-1 conjugation pathway is biochemically similar to the ubiquitin conjugation pathway but uses a distinct set of enzymes and regulatory mechanisms. We also show that p18(Ubc9) interacts specifically with the internal repeat domain of RanBP2, which is a substrate for SUMO-1 conjugation in Xenopus egg extracts.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas Ativadoras de GTPase , Ligases/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares , Proteínas Nucleares/metabolismo , Enzimas de Conjugação de Ubiquitina , Ubiquitinas/metabolismo , Animais , Chaperonas Moleculares , Proteínas Recombinantes de Fusão/metabolismo , Proteína SUMO-1 , Xenopus , Proteínas de Xenopus
11.
Mol Cell Biol ; 17(7): 4080-6, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9199343

RESUMO

The Mpv 20 transgenic mouse strain was created by infection of embryos with a defective retrovirus. When Mpv 20 heterozygous animals were crossed, no homozygous neonatal mice or midgestation embryos were identified. When embryos from heterozygous crosses were cultured in vitro, approximately one quarter arrested as uncompacted eight-cell embryos, indicating that proviral insertion resulted in a recessive lethal defect whose phenotype was manifest very early in development. Molecular cloning of the Mpv 20 insertion site revealed that the provirus had disrupted the Npat gene, a gene of unknown function, resulting in the production of a truncated Npat mRNA. Expression of the closely linked Atm gene was found to be unaffected by the provirus.


Assuntos
Proteínas de Ciclo Celular , Fase de Clivagem do Zigoto , Camundongos Transgênicos/embriologia , Proteínas Nucleares , Proteínas Serina-Treonina Quinases , Proteínas/genética , Provírus , Retroviridae/genética , Integração Viral , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Sequência de Bases , Clonagem Molecular , Proteínas de Ligação a DNA , Vírus Defeituosos , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Dados de Sequência Molecular , Proteínas Supressoras de Tumor
12.
Mol Cell Biol ; 19(3): 2366-72, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10022922

RESUMO

The xeroderma pigmentosum group G (XP-G) gene (XPG) encodes a structure-specific DNA endonuclease that functions in nucleotide excision repair (NER). XP-G patients show various symptoms, ranging from mild cutaneous abnormalities to severe dermatological impairments. In some cases, patients exhibit growth failure and life-shortening and neurological dysfunctions, which are characteristics of Cockayne syndrome (CS). The known XPG protein function as the 3' nuclease in NER, however, cannot explain the development of CS in certain XP-G patients. To gain an insight into the functions of the XPG protein, we have generated and examined mice lacking xpg (the mouse counterpart of the human XPG gene) alleles. The xpg-deficient mice exhibited postnatal growth failure and underwent premature death. Since XPA-deficient mice, which are totally defective in NER, do not show such symptoms, our data indicate that XPG performs an additional function(s) besides its role in NER. Our in vitro studies showed that primary embryonic fibroblasts isolated from the xpg-deficient mice underwent premature senescence and exhibited the early onset of immortalization and accumulation of p53.


Assuntos
Reparo do DNA , Proteínas de Ligação a DNA/fisiologia , Endonucleases/fisiologia , Xeroderma Pigmentoso/genética , Animais , Animais Recém-Nascidos , Senescência Celular/genética , Senescência Celular/fisiologia , Dano ao DNA/efeitos da radiação , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Feminino , Humanos , Cinética , Longevidade/genética , Longevidade/fisiologia , Masculino , Camundongos , Camundongos Knockout , Mutagênese , Proteínas Nucleares , Fatores de Transcrição , Raios Ultravioleta
13.
Cancer Res ; 53(3): 495-9, 1993 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8425182

RESUMO

UVS1 is an intermediately UV-sensitive Chinese hamster ovary mutant originally isolated by its hypersensitivity to an anticancer drug, 1-[(4-amino-2-methyl-5-pyrimidinyl)methyl]-3-(2-chloroethyl)-3-nitrosour ea hydrochloride. By cell fusion analysis, UVS1 complemented the UV sensitivity of the mouse lymphoma cell line US31 from the eighth complementation group of UV-sensitive rodent cell lines. By enzyme-linked immunosorbent assay we found that within 3 h after UV irradiation both pyrimidine dimers and (6-4)photoproducts in UVS1 were not removed from chromosomal DNA in UVS1 at all. Twenty-four h after UV irradiation the removal rate of (6-4)photoproducts was intermediate between CHO9, the parental cell line, and 43-3B, a UV-hypersensitive Chinese hamster ovary mutant of the complementation group 1, whereas the pyrimidine dimers in UVS1 were removed less efficiently as 43-3B. Alkaline elution assay showed that the incising activity to damaged DNA after UV irradiation of UVS1 was as low as that of 43-3B. The number of 1-[(4-amino-2-methyl-5-pyrimidinyl)methyl]-3-(2-chloroethyl)-3-nitrosour ea hydrochloride-induced DNA interstrand cross-links of UVS1 was almost equal to that of 43-3B and about 1.5 times more than that of CHO9, suggesting that the gene products defective in UVS1 and 43-3B are essential for the excision repair of DNA damages produced by 1-[(4-amino-2-methyl-5-pyrimidinyl)methyl]-3-(2-chloroethyl)-3-nitrosour ea hydrochloride.


Assuntos
Células CHO/efeitos da radiação , Dano ao DNA , Raios Ultravioleta , Animais , Células CHO/fisiologia , Linhagem Celular , Cricetinae , DNA/efeitos dos fármacos , DNA/genética , DNA/efeitos da radiação , Reparo do DNA , DNA de Neoplasias/efeitos dos fármacos , DNA de Neoplasias/genética , DNA de Neoplasias/efeitos da radiação , Genoma , Cinética , Linfoma/genética , Linfoma/fisiopatologia , Camundongos , Mutação , Nimustina/farmacologia , Sensibilidade e Especificidade , Células Tumorais Cultivadas/efeitos da radiação
14.
Cancer Res ; 41(5): 1958-66, 1981 May.
Artigo em Inglês | MEDLINE | ID: mdl-7214364

RESUMO

Clinicopathological, radiological, and histological studies were performed on urinary bladder neoplasia induced by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in five adult beagle dogs and in ten adult mongrel dogs. Tumors of the urinary bladder developed in dogs given various daily doses of BBN p.o. for different periods. The latent period of tumor induction was 4 years in dogs receiving a daily dose of 80 mg of BBN, 2 to 2.5 years in dogs receiving a daily dose of 160 mg of BBN, and 1.5 years in dogs receiving a daily dose of 240 mg of BBN. The total dose of BBN ingested by the dogs until the first tumors were observed by urological examinations was nearly the same in all groups, 100 to 140 g. These results suggest that there is a correlation between dose and induction time, but further dose-response studies are required. Histologically, tumors of the urinary bladder were transitional cell papillomas or transitional cell carcinomas resembling morphologically those found in human cases. It is possible to observe the process of development of urinary bladder tumors from initial lesions to invasive tumors using routine urological examinations. We believe that this experimental model is valuable for clinicopathological studies of urinary bladder tumors.


Assuntos
Butilidroxibutilnitrosamina , Nitrosaminas , Neoplasias da Bexiga Urinária/induzido quimicamente , Animais , Carcinoma/induzido quimicamente , Cistoscopia , Cães , Feminino , Hematúria/induzido quimicamente , Hiperplasia , Masculino , Neoplasias Experimentais/induzido quimicamente , Papiloma/induzido quimicamente , Neoplasias da Bexiga Urinária/patologia
15.
Oncogene ; 18(52): 7495-505, 1999 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-10602508

RESUMO

Ku antigen is a complex of Ku70 and Ku80 subunits and plays an important role in not only DNA double-strand breaks (DSB) repair and V(D)J recombination, but also in growth regulation. Ku is generally believed to always form and function as heterodimers on the basis of in vitro observations. Here we demonstrate that the localization of Ku80 does not completely coincide with that of Ku70. Ku70 and Ku80 were colocalized in the nucleus in the interphase but not in the late telophase/early G1 phase of the cell cycle. Since the in vivo function of Ku might be partially regulated by the control of its transport, we attempted to investigate the molecular mechanisms underlying the nuclear translocation of Ku. The nuclear translocation of Ku80 started during the late telophase/early G1 phase after the nuclear envelope was formed and this was preceded by the nuclear translocation of Ku70. Furthermore, we found that the Ku80 protein was transported to the nucleus without heterodimerization with Ku70. To understand in detail the mechanism of transport of Ku80, we attempted to identify the nuclear localization signal (NLS) of Ku80 and defined to a region spanning nine amino acid residues (positions 561 - 569). The Ku80 NLS was demonstrated to be mediated to the nuclear rim by two components of PTAC58 and PTAC97. All these findings support the idea that Ku80 can translocate to the nucleus using its own NLS independent of the translocation of Ku70.


Assuntos
Antígenos Nucleares , Núcleo Celular/metabolismo , DNA Helicases , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Sequência de Aminoácidos , Transporte Biológico , Ciclo Celular/genética , Citoplasma/metabolismo , Fase G1/genética , Proteínas de Fluorescência Verde , Humanos , Imuno-Histoquímica/métodos , Membranas Intracelulares/metabolismo , Autoantígeno Ku , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Telófase/genética , Células Tumorais Cultivadas , alfa Carioferinas
16.
Circulation ; 104(24): 2883-5, 2001 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-11739300

RESUMO

BACKGROUND: Reactive oxygen species (ROS) can cause an oxidative modification of nucleotides, such as 8-oxo-7,8-dihydrodeoxyguanosine triphosphate (8-oxo-dGTP), which can lead to defects in DNA replication. The misincorporation of 8-oxo-dGTP into DNA is prevented by 8-oxo-dGTPase, which hydrolyzes 8-oxo-dGTP into 8-oxo-dGMP. The changes in this defensive system have not yet been examined in failing hearts, in which the generation of ROS increases. METHODS AND RESULTS: Myocardial infarction (MI) was created in mice by ligating the left coronary artery. Four weeks later, the left ventricle was dilated and contractility was diminished on echocardiography. The generation of ROS, as measured by electron spin resonance spectroscopy with 4-hydroxy-2,2,6,6-tetramethyl-piperidine-N-oxyl, increased in the noninfarcted left ventricle from MI mice. The formation of thiobarbituric acid-reactive substances also increased in the mitochondria from MI mice. 8-Oxo-dGTPase was detected in the mitochondrial fractions isolated from MI mice using a Western blot analysis with an antibody to its human homologue (hMTH1). Immunohistochemistry showed positive staining for hMTH1 was localized in the cardiac myocytes. CONCLUSIONS: The level of 8-oxo-dGTPase increased in the mitochondria isolated from post-MI hearts as oxidative stress increased, thus suggesting that a preventive mechanism is activated against ROS-induced DNA damage. As a result, 8-oxo-dGTPase is considered a useful marker of mitochondrial oxidative stress in heart failure.


Assuntos
Dano ao DNA , Enzimas Reparadoras do DNA , Mitocôndrias Cardíacas/metabolismo , Infarto do Miocárdio/metabolismo , Estresse Oxidativo/fisiologia , Monoéster Fosfórico Hidrolases/metabolismo , Animais , Western Blotting , Ecocardiografia , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Hemodinâmica , Humanos , Células Jurkat , Pulmão/crescimento & desenvolvimento , Masculino , Camundongos , Tamanho do Órgão , Espécies Reativas de Oxigênio/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
17.
Circulation ; 104(2): 134-6, 2001 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-11447074

RESUMO

BACKGROUND: The generation of reactive oxygen species (ROS) is enhanced in the failing myocardium. We hypothesized that ROS were also increased in the limb skeletal muscles in heart failure. Methods and Results-- Myocardial infarction (MI) was created in mice by ligating the left coronary artery. After 4 weeks, the left ventricle was dilated and contractility was diminished by echocardiography. Left ventricular end-diastolic pressure was elevated after MI in association with an increase in lung weight/body weight and the presence of pleural effusion. The generation of ROS in the limb muscles, including the soleus and gastrocnemius muscles, which were excised after MI, was measured by electron spin resonance spectroscopy with 4-hydroxy-2,2,6,6-tetramethyl-piperidine-N-oxyl (hydroxy-TEMPO). Overall, generation was increased, but it was attenuated in the presence of dimethylthiourea or 4,5-dihydroxy-1,2-benzenedisulfonic disodium salt in the reaction mixture, indicating increased generation of hydroxyl radicals originating from superoxide anion. Thiobarbituric acid-reactive substance formation was also increased in muscles after MI. Mitochondrial complex I and III activities were both decreased after MI, which may have caused the functional uncoupling of the respiratory chain and ROS production. Antioxidant enzyme activities, including superoxide dismutase, catalase, and glutathione peroxidase, were comparable between groups. CONCLUSIONS: Skeletal muscle in post-MI heart failure expressed an increased amount of ROS in association with ROS-mediated lipid peroxidation. This supports the hypothesis that oxidative stress may cause (at least in part) skeletal muscle dysfunction in heart failure.


Assuntos
Modelos Animais de Doenças , Insuficiência Cardíaca/metabolismo , Músculo Esquelético/metabolismo , Infarto do Miocárdio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Catalase/metabolismo , Ecocardiografia , Eletrocardiografia , Espectroscopia de Ressonância de Spin Eletrônica , Tolerância ao Exercício , Glutationa Peroxidase/metabolismo , Insuficiência Cardíaca/etiologia , Hemodinâmica , Peroxidação de Lipídeos , Masculino , Camundongos , Infarto do Miocárdio/complicações , Tamanho do Órgão , Marcadores de Spin , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/etiologia
18.
Genetics ; 113(2): 433-47, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3087816

RESUMO

Two aphidicolin-resistant cell mutants (AC 12 and AC 41) with a fourfold increase in spontaneous frequency of sister chromatid exchanges (SCEs) were obtained out of over 400 aphidicolin-resistant mutants isolated from mouse lymphoma L5178Y cells. They also exhibited three- to fourfold increases in spontaneous frequency of chromosome aberrations (CAs). To determine whether the high level of SCE frequency in AC 12 is caused by 5-bromodeoxyuridine (BrdUrd) used for visualizing SCEs, the effect of BrdUrd incorporated into DNA on SCE induction was analyzed. The SCE frequencies in AC 12 remained constant at BrdUrd incorporation levels corresponding to 2-90% substitution for thymidine in DNA. In addition, the small amount of BrdUrd incorporated into both daughter and parenteral DNA strands in AC 12 had minimal effect on SCE induction. Furthermore, AC 12 and AC 41 were slightly resistant to BrdUrd with respect to the induction of CAs, the inhibition of cell-cycle progression and the decrease in mitotic activity. These findings suggest that the high incidence of SCEs in AC 12 and AC 41 is formed by their intrinsic defects, not by the effects of BrdUrd used. The analysis of SCE frequencies in hybrid cells between these mutants and the parental L5178Y revealed that the genetic defects in AC 12 and AC 41 appear to be recessive, and that these two mutants belong to the same complementation group. Furthermore, AC 12 belonged to a different complementation group from ES 4, which was isolated previously from L5178Y as an SCE mutant with a twofold higher frequency of spontaneous SCEs. This finding indicates that at least two different genetic defects participate in the formation of the high incidence of spontaneous SCEs in mouse cells. These SCE mutants would provide valuable cell materials for studying the molecular mechanism of SCE formation.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Diterpenos/toxicidade , Leucemia L5178/patologia , Leucemia Experimental/patologia , Mutação , Troca de Cromátide Irmã/efeitos dos fármacos , Animais , Afidicolina , Bromodesoxiuridina/farmacologia , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Resistência a Medicamentos , Cinética , Camundongos , Tioguanina/toxicidade
19.
DNA Res ; 2(6): 269-75, 1995 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-8867801

RESUMO

A subtraction procedure was developed for identification and isolation of a human gene transcribed in mouse transformant cells. The procedure was based on subtractive enrichment of the products that were amplified by the combination of reverse transcription and polymerase chain reaction from the 3'-untranslated region (3'-UTR) of human poly(A)+ RNA expressed in the mouse transformant cells. To assess the ability and usefulness of the procedure, we attempted to recover the human purH gene from a mouse transformant cell line, which was originally established by functional complementation using the human metaphase chromosome-mediated gene transfer technique from a mouse purH-negative mutant cell line. Using our procedure, a part of the human transcript in the transformant cells was successfully identified and isolated. The full-length cDNA was isolated using the 3'-UTR clone as a probe, and its biological activity was confirmed by introducing it into the mouse purH-negative mutant cells.


Assuntos
Aciltransferases/genética , Clonagem Molecular/métodos , Hidroximetil e Formil Transferases , Nucleotídeo Desaminases/genética , RNA Mensageiro/genética , Sequências Reguladoras de Ácido Nucleico/genética , Adenina , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , DNA Complementar/genética , Genes , Teste de Complementação Genética , Humanos , Camundongos , Dados de Sequência Molecular , Mutação , Fosforribosilaminoimidazolcarboxamida Formiltransferase , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
20.
Bone ; 19(5): 549-55, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8922656

RESUMO

We measured bone mineral density (BMD) at the lumbar spine (LS-BMD), 1/3 radius (1/3R-BMD), and ultradistal radius (UDR-BMD) in 59 men (4 with spine fractures and 4 with nonspine fractures) and 65 women (10 with spine fractures and 9 with nonspine fractures), all receiving maintenance hemodialysis (HD). The BMD at each site expressed absolutely in g/cm2 was significantly lower in women than in men (p = 0.0001). In men, the absolute and age-matched values of both 1/3R- and UDR-BMD were inversely and significantly correlated with the duration of HD, and with serum alkaline phosphatase and parathyroid hormone levels (p < 0.05), whereas such relationships were obscure in women. On the other hand, the absolute values of BMD at each site in women but not in men were inversely and significantly correlated with patient age (p < 0.001). In both sexes, R-BMD was significantly lower in both the spine and nonspine fracture groups than in the nonfracture group (p < 0.05 and p < 0.01, respectively), whereas the only significant difference in LS-BMD was that it was lower in women with spine fractures than in women without fractures, when expressed as its absolute value (p < 0.05). By receiver operating characteristic analyses, both the absolute and age-matched values of R-BMD were better than LS-BMD as a determinant of non-spine fracture histories, and were similar to absolute LS-BMD as a determinant of spine fracture histories. We conclude that R-BMD is more valuable than LS-BMD for discriminating HD patients with all types of fractures from those without fractures.


Assuntos
Densidade Óssea/fisiologia , Vértebras Lombares/fisiologia , Rádio (Anatomia)/fisiologia , Diálise Renal , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas do Rádio/fisiopatologia , Diálise Renal/normas , Estudos Retrospectivos , Fatores Sexuais , Fraturas da Coluna Vertebral/fisiopatologia
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