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1.
Osteoporos Int ; 30(3): 621-628, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30460382

RESUMO

In osteoporosis patients receiving antiresorptive medications, stopping the drug and delaying tooth extraction has been suggested to reduce the risk of osteonecrosis of the jaw (ONJ). However, postponing tooth extraction for ≥ 2 months was associated with an increased risk of delayed wound healing beyond 8 weeks after extraction, a risk factor for developing ONJ. INTRODUCTION: A long waiting time before tooth extraction could result from concern about a potential increased risk of osteonecrosis of the jaw (ONJ) in osteoporosis patients. We clarified whether a long waiting time before tooth extraction during the past year may be associated with an increased risk of delayed wound healing beyond 8 weeks after tooth extraction, which may be a risk factor of ONJ. METHODS: Of 5639 patients aged ≥ 60 years who visited our 20 clinics or hospitals and answered a structured questionnaire, 426 patients (151 men, 275 women) aged 60-96 years comprised the final participants in this study. Self-reported kyphosis was used as a surrogate marker of vertebral fractures. Stepwise logistic regression analysis, adjusted for covariates, was used to calculate the odds ratio (OR) and the 95% confidence interval (CI) for the presence of delayed wound healing longer than 8 weeks after tooth extraction during the past year based on the duration before extraction. RESULTS: Subjects who had waited > 2 months for tooth extraction had a significantly higher risk of delayed wound healing compared with those whose tooth was extracted within 1 month (OR = 7.23; 95% CI = 2.19-23.85, p = 0.001) regardless if antiresorptive medications for osteoporosis were used. The presence of self-reported kyphosis was significantly associated with an increased risk of delayed wound healing (OR = 5.08; 95% CI = 1.11-23.32, p = 0.036). CONCLUSIONS: A long waiting time before tooth extraction may be a risk factor for delayed wound healing beyond 8 weeks after extraction in patients aged ≥ 60 years.


Assuntos
Osteoporose/fisiopatologia , Extração Dentária , Cicatrização/fisiologia , Idoso , Idoso de 80 Anos ou mais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/prevenção & controle , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/farmacologia , Feminino , Humanos , Cifose/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/fisiopatologia , Período Pós-Operatório , Fatores de Risco , Fraturas da Coluna Vertebral/fisiopatologia , Fatores de Tempo , Listas de Espera , Cicatrização/efeitos dos fármacos
2.
Eur J Pain ; 21(1): 140-147, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27378656

RESUMO

BACKGROUND AND OBJECTIVE: We developed a quantitative method to measure movement representations of a phantom upper limb using a bimanual circle-line coordination task (BCT). We investigated whether short-term neurorehabilitation with a virtual reality (VR) system would restore voluntary movement representations and alleviate phantom limb pain (PLP). METHODS: Eight PLP patients were enrolled. In the BCT, they repeatedly drew vertical lines using the intact hand and intended to draw circles using the phantom limb. Drawing circles mentally using the phantom limb led to the emergence of an oval transfiguration of the vertical lines ('bimanual-coupling' effect). We quantitatively measured the degree of this bimanual-coupling effect as movement representations of the phantom limb before and immediately after short-term VR neurorehabilitation. This was achieved using an 11-point numerical rating scale (NRS) for PLP intensity and the Short-Form McGill Pain Questionnaire (SF-MPQ). During VR neurorehabilitation, patients wore a head-mounted display that showed a mirror-reversed computer graphic image of an intact arm (the virtual phantom limb). By intending to move both limbs simultaneously and similarly, the patients perceived voluntary execution of movement in their phantom limb. RESULTS: Short-term VR neurorehabilitation promptly restored voluntary movement representations in the BCT and alleviated PLP (NRS: p = 0.015; 39.1 ± 28.4% relief, SF-MPQ: p = 0.015; 61.5 ± 48.5% relief). Restoration of phantom limb movement representations and reduced PLP intensity were linearly correlated (p < 0.05). CONCLUSIONS: VR rehabilitation may encourage patient's motivation and multimodal sensorimotor re-integration of a phantom limb and subsequently have a potent analgesic effect. SIGNIFICANCE: There was no objective evidence that restoring movement representation by neurorehabilitation with virtual reality alleviated phantom limb pain. This study revealed quantitatively that restoring movement representation with virtual reality rehabilitation using a bimanual coordination task correlated with alleviation of phantom limb pain.


Assuntos
Atividade Motora/fisiologia , Reabilitação Neurológica/métodos , Membro Fantasma/reabilitação , Extremidade Superior , Realidade Virtual , Adulto , Plexo Braquial/lesões , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimento , Medição da Dor , Membro Fantasma/etiologia , Membro Fantasma/fisiopatologia , Amplitude de Movimento Articular , Interface Usuário-Computador
3.
J Nanosci Nanotechnol ; 17(3): 1616-621, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-29693985

RESUMO

The influence of Y2O3 nanolayers on thermoelectric performance and structure of 2% Al-doped ZnO (AZO) thin films has been studied. Multilayers based on five 50 nm thick AZO layers alternated with few nanometers thick Y2O3 layers were prepared by pulsed laser deposition on Al2O3 single crystals by alternate ablation of AZO target and Y2O3 target. The number of laser shots on Y2O3 target was maintained very low (5, 10 and 15 pulses in three separate experiments. The main phase (AZO) presents polycrystalline orientation and typical columnar growth not affected by the presence of Y2O3 nanolayers. The multilayer with 15 laser shots of Y2O3 showed best thermoelectric performance with electrical conductivity σ 48 S/cm and Seebeck coefficient S = −82 µV/K, which estimate power factor (S2·σ) about 0.03 × 10−3 W m−1 K−2 at 600 K. The value of thermal conductivity (κ) was found 10.03 W m−1 K−1 at 300 K, which is one third of typical value previously reported for bulk AZO. The figure of merit, ZT = S2·σ·T/κ, is calculated 9.6 × 10−4 at 600 K. These results demonstrated the feasibility of nanoengineered defects insertion for the depression of thermal conductivity.

5.
Haemophilia ; 21(5): 653-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25929725

RESUMO

INTRODUCTION: Autoimmune haemophilia-like disease (or haemorrha-philia) due to anti-factor XIII (FXIII; F13 to avoid confusion with FVIII or FXII) antibodies (termed AH13) is a severe bleeding disorder. Although AH13 is thought to be rare, 'the number of its diagnosed patients' has recently increased in Japan. However, its prevalence remains unknown. AIM: To improve understanding of this disease, we examined and diagnosed 32 'new' Japanese patients with AH13. METHODS: The presence of antibodies against F13-A subunit and/or F13-B subunit was confirmed by using a dot blot test and enzyme-linked immunosorbent assays. RESULTS: Most of our patients had autoantibodies against the F13-A subunit (88%). A predominance of men (59%) was observed. The mean age and residual F13 activity of our AH13 cohort were 71.7 years and 10.5% of normal, respectively, and 53% of cases were idiopathic. Autoimmune disorders and malignancies were the leading underlying disease (both 16%). Intramuscular and subcutaneous bleeding were the leading symptoms (both 72%). Most of our patients were treated with F13 concentrates (72%) to arrest bleeding and with prednisolone (81%) to eradicate anti-F13 autoantibodies. Cyclophosphamide and rituximab (both 25%) were also administered. The mortality of AH13 was high (22%), and haemorrhage was the major cause of death (71%). Moreover, 13% of our AH13 patients were diagnosed after haemorrhagic death. CONCLUSION: Physicians/haematologists must raise the awareness of AH13 as a life-threatening disease. This report represents the only experience of a nationwide survey, and may contribute to a diagnosis on potentially overlooked non-Japanese AH13 patients in other countries in the world.


Assuntos
Autoanticorpos/imunologia , Doenças Autoimunes/imunologia , Fator XIII/imunologia , Hemofilia A/imunologia , Adulto , Idoso , Povo Asiático , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/tratamento farmacológico , Feminino , Hemofilia A/diagnóstico , Hemofilia A/tratamento farmacológico , Hemostáticos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento
6.
J Thromb Haemost ; 13(5): 802-14, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25703841

RESUMO

BACKGROUND: Autoimmune hemophilia-like disease (hemorrha-philia or hemorrhagic disorder) caused by anti-factor XIII antibodies (termed AH13) or 'autoimmune FXIII deficiency' is a life-threatening bleeding disorder. AH13 was thought to be rare worldwide. OBJECTIVES: Because the number of diagnosed AH13 cases has recently been increasing, at least in Japan, we conducted a nationwide survey supported by the Japanese Ministry of Health, Labor, and Welfare, and explored the pathologic mechanism(s) of AH13. METHODS: We diagnosed AH13 cases during the last 11 years according to the presence of anti-FXIII autoantibodies confirmed by a dot blot assay and ELISA, and characterized 33 of these both immunologically and biochemically. RESULTS: The AH13 cases were immunologically classified into three types, Aa, Ab, and B. Type Aa autoantibodies, observed in 27 cases, were directed against the native FXIII A subunit (FXIII-A), and blocked FXIII activation. The autoantibodies not only prevented assembly of new FXIII-A2 B2 heterotetramers, but also removed FXIII-A from native FXIII-A2 B2 heterotetramers by forming an FXIII-A-IgG complex. Type Ab autoantibodies, detected in three cases, preferentially bound to activated FXIII-A and inhibited its activity. Type Aa and Ab autoantibodies were 'neutralizing' FXIII antibodies (or FXIII inhibitors), and thus could be screened with functional assays. Type B antibodies, detected in two cases, were non-neutralizing anti-FXIII B subunit (FXIII-B) autoantibodies that possibly accelerated the clearance of FXIII, and thus could be diagnosed exclusively with immunologic methods. CONCLUSION: There are three major types of anti-FXIII autoantibody, with distinct targets and mechanisms that cause AH13.


Assuntos
Autoanticorpos/imunologia , Fator XIII/imunologia , Isoenzimas/imunologia , Ensaio de Imunoadsorção Enzimática , Fator XIII/química , Humanos , Inibidores de Serina Proteinase/farmacologia
7.
Clin Radiol ; 69(12): 1273-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25246336

RESUMO

AIM: To evaluate radiation-induced myocardial damage after mediastinal radiotherapy using MRI. MATERIALS AND METHODS: Between May 2010 and April 2011, delayed contrast-enhanced MRI was performed for patients who had maintained a complete response to curative radiotherapy for oesophageal cancer for more than 6 months. The patients received radiotherapy with a median total dose of 66 Gy (60-70 Gy) for the primary tumour and metastatic lymph nodes. Images of MRI were analysed by a 17-segment method recommended by the American Heart Association. A segment included mainly in the 40 Gy dose line was defined as Segment 40 Gy, a segment included mainly in the 60 Gy dose line as Segment 60 Gy, and a segment out of the radiation fields as Segment OUT. The percentage of late gadolinium enhancement (LGE) was examined in those categories. The layer in which LGE was predominantly distributed was evaluated for each patient. RESULTS: Four hundred and eight segments in 24 patients were analysed. The median interval from completion of radiotherapy to MRI was 23.5 months (range 6-88 months). LGE was detected in 12 of the 24 patients. LGE was detected in 15.38% of Segment 40 Gy cases, 21.21% of Segment 60 Gy cases, and 0% of Segment OUT cases. LGE in mid-myocardial and subendocardial layers was detected in 11 patients and one patient, respectively. CONCLUSION: LGE suggesting radiation induced myocardial fibrosis was observed by performing delayed contrast-enhanced MRI. Care should be taken when planning radiotherapy to avoid late cardiac damage.


Assuntos
Cardiomiopatias/etiologia , Cardiomiopatias/patologia , Neoplasias Esofágicas/radioterapia , Coração/efeitos da radiação , Imageamento por Ressonância Magnética/métodos , Miocárdio/patologia , Lesões por Radiação/complicações , Idoso , Meios de Contraste , Neoplasias Esofágicas/complicações , Feminino , Gadolínio , Humanos , Aumento da Imagem/métodos , Masculino , Radioterapia/efeitos adversos , Dosagem Radioterapêutica , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos
8.
Haemophilia ; 20(2): 255-62, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24286209

RESUMO

Factor XIII (FXIII) consists of the A and B subunits (FXIII-A and FXIII-B) and stabilizes fibrin clots. Defects in either the FXIII-A or FXIII-B gene lead to congenital FXIII deficiency, which manifests a life-long haemorrhagic tendency. Thus, prophylactic FXIII replacement therapy is recommended. To establish a management plan for a 30-year-old male patient with 'indefinite' FXIII deficiency (<40% of the normal FXIII), he was characterized by state-of-the-art techniques as guided by the FXIII/Fibrinogen subcommittee of ISTH/SSC. FXIII activity turned out to be virtually undetectable by three functional assays. Four immunological assays detected essentially no FXIII protein, FXIII-A antigen, and A2 B2 antigen, but normal FXIII-B antigen. Accordingly, he was diagnosed as a 'severe' FXIII-A deficiency case. He had no anti-FXIII antibodies, because a 1:1 cross-mixing test (ammonia release assay) and a five-step mixing test (amine incorporation assay) between his plasma and normal plasma demonstrated deficiency patterns. Furthermore, a dosing test using plasma-derived FXIII concentrates revealed its normal recovery. DNA sequencing analysis identified two novel mutations, W187X & G273V, in the F13A gene. Genetic analyses confirmed that he was a compound heterozygote and his mother and sister were heterozygotes of either one of these mutations, indicating the hereditary nature of this disorder. Molecular modelling predicted that the G273V mutation would cause clashes with the surrounding residues in the core domain of FXIII-A, and ultimately would result in the instability of the mutant molecule. Detailed characterization of 'indefinite' FXIII deficiency made it possible to make its definite diagnosis and best management plan.


Assuntos
Deficiência do Fator XIII/diagnóstico , Deficiência do Fator XIII/genética , Fator XIII/genética , Mutação , Adulto , Sequência de Aminoácidos , Substituição de Aminoácidos , Códon , Fator XIII/química , Fator XIII/imunologia , Fator XIII/metabolismo , Heterozigoto , Humanos , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Linhagem , Guias de Prática Clínica como Assunto , Conformação Proteica , Alinhamento de Sequência , Índice de Gravidade de Doença
9.
Haemophilia ; 19(3): 415-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23279035

RESUMO

Congenital factor XIII (FXIII) deficiency is a severe bleeding disorder. We previously identified an Arg260Cys missense mutation and an exon-IV deletion in patients' A subunit genes, F13A. To characterize the molecular/cellular basis of this disease, we expressed a wild type and these mutant A subunits in baby hamster kidney (BHK) cells. The mutant proteins were expressed less efficiently than the wild type. These mutants gradually decreased inside BHK cells, whereas the wild type remained largely unchanged. The decline/decrease in these mutants was completely blocked/restored by a potent proteasome inhibitor, MG-132. This was consistent with the prediction by molecular modelling that the mutant molecules would lose the native structure of wild-type molecule, leading to their instability and degeneration and ultimately to degradation. These mutants might have significantly altered conformations, resulting in the rapid degradation by the proteasome inside the synthesizing cells, and ultimately leading to FXIII deficiency.


Assuntos
Fator XIIIa/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Animais , Linhagem Celular , Cricetinae , Éxons , Fator XIIIa/genética , Deleção de Genes , Leupeptinas/farmacologia , Microscopia Confocal , Mutação de Sentido Incorreto , Complexo de Endopeptidases do Proteassoma/química , Proteólise/efeitos dos fármacos
10.
Haemophilia ; 18(4): 618-20, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22356719

RESUMO

Acquired factor XIII (FXIII) deficiency due to an autoantibody against FXIII is a very rare, yet potentially life-threatening bleeding disorder. As the standard coagulation tests (prothrombin time and activated partial thromboplastin time) are normal, the specialized tests are required to make an accurate diagnosis. Here, we report a case of acquired FXIII deficiency with severe bleeding symptoms. A 75-year-old man was referred to our hospital because of severe bleeding tendency after a tooth extraction. Laboratory findings showed that routine coagulation studies were normal, but factor XIII (FXIII) activity was low (3%). The presence of FXIII inhibitor was detected with dot blotting studies. Although the bleeding tendency was very severe, it was successfully controlled by infusion of FXIII concentrates combined with immunosuppressive treatment (oral prednisolone). Fibrin cross-linking study showed the significant delay of the γ-chain dimer and α-chain polymer formation. Western blotting revealed the marked decrease in FXIII-A level. The mixing study of FXIII activity measured using amine-incorporation assay showed the incomplete inhibition pattern. There seems to be little agreement as to the treatment strategy of acquired FXIII deficiency. In this patient, the use of FXIII concentrates was very useful in the initial treatment of bleeding symptom. The use of steroids was also effective in increasing FXIII activity without any serious complications.


Assuntos
Deficiência do Fator XIII/complicações , Hematoma/etiologia , Tela Subcutânea/irrigação sanguínea , Idoso , Fator XIII/metabolismo , Deficiência do Fator XIII/diagnóstico , Humanos , Masculino
11.
Aesthetic Plast Surg ; 36(3): 534-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22361958

RESUMO

BACKGROUND: Partial detachment of the superficial musculoaponeurotic system (SMAS) by dissection of the premasseter space (PMS) is an option for enhancing the effectiveness of SMAS-based rhytidectomy. The aim of this study was to identify the underlying cause of the potential risk of motor nerve impairment sometimes caused by PMS dissection and to consider the effective use of PMS dissection, especially in Asians. METHODS: Detailed dissection was carried out on six fixed Japanese cadavers to evaluate facial nerve pathways around the PMS. RESULTS: The anterior wall of the PMS was opaque because each face exhibited fibers of various thicknesses within and around the anterior border of the masseter. The ascending ramifications of the buccal trunk ran through the fibers, outside the anterior border of the masseter in some faces but within it in others. CONCLUSIONS: This study revealed the presence of a danger zone when dissecting the PMS in Asians. Severing the fibers that fix the SMAS to the masseter fascia around the anterior border of the masseter is sometimes unavoidable to attain good mobility of the SMAS. Surgeons must be mindful of the fibers near the anterior border of the masseter because they may be outside the PMS and contain buccal trunk ramifications; the anterior wall of the PMS tends to be opaque in Asians. Nonetheless, the extent of PMS dissection should be determined on an individual basis. The present findings may help to reduce relevant risks in Asian patients and standardize procedures for effective rhytidectomy. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the table of contents or the online instructions to authors at www.springer.com/00266.


Assuntos
Nervo Facial/anatomia & histologia , Ritidoplastia/métodos , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Cadáver , Feminino , Humanos , Masculino , Vias Neurais
14.
J Thromb Haemost ; 7(7): 1084-91, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19422463

RESUMO

OBJECTIVES: The purpose of this study was to elucidate the molecular bases of the heterogeneity of the B subunit of coagulation factor XIII (FXIII-B), classified by isoelectric focusing into its three population-associated major phenotypes. METHODS AND RESULTS: By genetic sequencing and polymerase chain reaction (PCR)-restriction fragment length polymorphism analyses, a C-to-G change was identified in intron K for the Asian-associated major phenotype FXIII-B*3. A transcript containing the novel exon XII' was detected by reverse transcription PCR using hepatocyte cell lines with this allele. The exclusive existence of a novel C-terminal peptide in a homozygote of FXIII-B*3 was also detected by matrix-assisted laser-desorption ionization time of flight mass spectrometry. The FXIII-B*3 isoform had a C-terminus 15 residues longer than the other isoforms, containing two additional basic amino acids and one extra acidic amino acid. Accordingly, the C-to-G nucleotide substitution created an efficient splice acceptor AG dinucleotide, which resulted in allele-specific alternative splicing in intron K. When compared with FXIII-B*1, the third major phenotype, FXIII-B*2, had an A-to-G change in exon III, converting His95 to Arg, and a rare phenotype, FXIII-B*4, had an A-to-T change in exon VII, converting Glu368 to Val. CONCLUSIONS: We found an extremely rare event of complete allele-specific alternative splicing for FXIII-B. The FXIII-B*3 isoform had a distinct C-terminal peptide, while the FXIII-B*2 and FXIII-B*4 isoforms had His95 to Arg and Glu368 to Val substitutions, respectively, which led to differential isoelectric points of these isoforms. Such variations in the amino acid sequence of FXIII-B may have profound effects on its structure-function relationship, plasma FXIII levels, and disease susceptibility.


Assuntos
Alelos , Processamento Alternativo , Coagulação Sanguínea , Fator XIII/genética , Fibrinólise , Genética Populacional , Sequência de Aminoácidos , Sequência de Bases , Fator XIII/química , Humanos , Dados de Sequência Molecular , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , RNA Mensageiro/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
15.
Parasitol Res ; 103(6): 1333-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18690475

RESUMO

Stem barks of Anogeissus leiocarpus and Terminalia avicennoides widely used in Africa for treatment of some parasitic diseases were collected and made into methanolic extracts. The extracts were tested on four strains of promastigote forms of Leishmania in vitro. Solvent fractionation in aqueous, butanolic, and ethyl acetate layer indicated butanol and aqueous fractions to have a superior leishmanicidal activity. Chromatographic separation of the butanolic fraction on Sephadex LH-20 followed by nuclear magnetic resonance and correlation high-performance liquid chromatography revealed the presence of known hydrolyzable tannins and some related compounds-with castalagin as the major compound. The observed activity ranged from 62.5 to > or =150, 112.5 to > or =500, and 55 to >150 microg/ml for the crude methanolic extract, different solvent fractions, and the isolated compounds, respectively, on the four different Leishmania strains.


Assuntos
Combretaceae/química , Taninos Hidrolisáveis/farmacologia , Leishmania/efeitos dos fármacos , Casca de Planta/química , Caules de Planta/química , Animais , Taninos Hidrolisáveis/análise , Taninos Hidrolisáveis/isolamento & purificação , Leishmania/classificação , Medicinas Tradicionais Africanas , Testes de Sensibilidade Parasitária , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Plantas Medicinais/química
16.
J Thromb Haemost ; 6(5): 812-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18315549

RESUMO

BACKGROUND: Multiple studies suggest that the hemostatic and innate immune systems functionally cooperate in establishing the fraction of tumor cells that successfully form metastases. In particular, platelets and fibrinogen have been shown to support metastatic potential through a mechanism coupled to natural killer (NK) cell function. As the transglutaminase that ultimately stabilizes platelet/fibrin thrombi through the covalent crosslinking of fibrin, factor (F) XIII is another thrombin substrate that is likely to support hematogenous metastasis. OBJECTIVE: Directly define the role of FXIII in tumor growth, tumor stroma formation, and metastasis. METHODS: Tumor growth and metastatic potential were quantitatively and qualitatively evaluated in wild-type mice and gene-targeted mice lacking the catalytic FXIII-A subunit. RESULTS: Loss of FXIIIa function significantly diminished hematogenous metastatic potential in both experimental and spontaneous metastasis assays in immunocompetent mice. However, FXIII was not required for the growth of established tumors or tumor stroma formation. Rather, detailed analyses of the early fate of circulating tumor cells revealed that FXIII supports the early survival of micrometastases by a mechanism linked to NK cell function. CONCLUSIONS: Factor XIII is a significant determinant of metastatic potential and supports metastasis by impeding NK cell-mediated clearance of tumor cells. Given that these findings parallel previous observations in fibrinogen-deficient mice, an attractive hypothesis is that FXIII-mediated stabilization of fibrin/platelet thrombi associated with newly formed micrometastases increases the fraction of tumor cells capable of evading NK cell-mediated lysis.


Assuntos
Fator XIII/fisiologia , Células Matadoras Naturais/imunologia , Metástase Neoplásica/patologia , Neoplasias/etiologia , Células Neoplásicas Circulantes/patologia , Transglutaminases/metabolismo , Animais , Plaquetas , Fator XIII/metabolismo , Fibrina , Camundongos , Camundongos Knockout , Trombose , Evasão Tumoral/fisiologia
17.
J Eur Acad Dermatol Venereol ; 22(2): 168-73, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18211409

RESUMO

BACKGROUND: Mondor's disease (MD) is considered an inflammatory condition of superficial vasculitis that develops mainly in the anterolateral thoracoabdominal wall. The pathogenesis of the disease has been controversial, however, because of the lack of histopathologic methods for differentiating between the small vein and the lymphatic vessel. AIM: To objectively examine the origin of vascular lesions in MD, we investigated the endothelial cells of their blood and lymphatic vessels. METHODS: Immunohistochemical examinations were carried out on specimens involving vascular lesions from 16 patients with MD, using antibodies against von Willebrand factor and human lymphatic vessel endothelial hyaluronan receptor-1, which specifically discriminate between lymphatic and blood vessels. RESULTS: The histopathologic findings clearly showed thrombophlebitis in 14 patients, a lesion originating in the lymphatic vessel in one patient, and sclerosis that consisted of the artery together with veins in another. CONCLUSION: This study suggests that almost all cases of MD are due to thrombophlebitis, with a small minority due to lymphangitis or other conditions. We believe this study will contribute to the better recognition of the factual changes in the condition designated MD.


Assuntos
Endotélio Linfático/metabolismo , Endotélio Linfático/patologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Vasculite/patologia , Proteínas de Transporte Vesicular/metabolismo , Fator de von Willebrand/metabolismo , Parede Abdominal/patologia , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Linfangite/complicações , Linfangite/diagnóstico , Vasos Linfáticos/metabolismo , Vasos Linfáticos/patologia , Masculino , Pessoa de Meia-Idade , Tromboflebite/complicações , Tromboflebite/diagnóstico , Vasculite/etiologia , Vasculite/metabolismo , Veias/metabolismo , Veias/patologia
18.
J Thromb Haemost ; 5(11): 2250-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17958743

RESUMO

BACKGROUND AND OBJECTIVES: Protein Z (PZ), which regulates blood coagulation, is mainly synthesized in the liver. Its plasma level varies widely among individuals, and is highly sensitive to Warfarin. The mechanism for the basic transcription of the human PZ gene, however, has not been reported. The aim of this study was to elucidate the mechanism of gene regulation for PZ by characterizing its 5'-flanking region. METHODS AND RESULTS: A reporter gene assay using the human hepatoma cell line, HepG2, identified a minimal promoter region (site A) and two enhancer regions (sites B and C) in the PZ gene. DNase I footprinting and electromobility shift assays revealed binding of the liver-enriched transcriptional factor hepatocyte nuclear factor (HNF)-4alpha to site A, the ubiquitous transcriptional factor Sp1 to sites A and C, and an unidentified factor to site B. The co-transfection of an HNF-4alpha expression vector with reporter gene constructs to the non-hepatic cell line HeLa resulted in a significant increase of PZ promoter activity. CONCLUSIONS: HNF-4alpha plays a crucial role in human PZ gene expression in hepatocytic cells, and Sp1 is also important. These findings provide the first step toward understanding the mechanisms of the varying plasma PZ levels in individuals under physiological and pathological conditions.


Assuntos
Proteínas Sanguíneas/genética , Regulação da Expressão Gênica/fisiologia , Fator 4 Nuclear de Hepatócito/fisiologia , Fígado/química , Fator de Transcrição Sp1/fisiologia , Região 5'-Flanqueadora , Sítios de Ligação , Linhagem Celular Tumoral , Elementos Facilitadores Genéticos , Humanos , Regiões Promotoras Genéticas
19.
J Thromb Haemost ; 5(9): 1923-9, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17723131

RESUMO

BACKGROUND: An international collaborative study, involving 23 laboratories, was carried out, under the auspices of the FXIII Standardization Working Party (SWP), to calibrate the 1st International Standard (IS) for factor XIII (FXIII) plasma. METHODS: Potency estimates for the proposed candidate FXIII plasma (preparation Y: NIBSC code 02/206) were calculated relative to locally collected normal plasma pools (pool N), for both FXIII activity and antigen levels. RESULTS: Estimates of FXIII activity potency for preparation Y showed good agreement between laboratories, with an interlaboratory geometric coefficient of variation (GCV) of 11.5% and a mean value of 0.91 U mL(-1). Furthermore, there was a negligible difference in potencies by two commercially available methods, the potencies differing only by approximately 1%. Estimates of FXIII antigen (A(2)B(2) complex) potency for preparation Y showed good agreement between laboratories, with an interlaboratory GCV of 16.3% and a mean value of 0.93 U mL(-1). Accelerated degradation studies showed that the proposed standard is very stable, with a predicted loss of activity (and antigen) per year of< 0.06% at the recommended storage temperature of -20 degrees C. CONCLUSIONS: The suitability and potency of preparation Y were considered by the participants, members of the ISTH/SSC FXIII Subcommittee, the Scientific and Standardization Committee and the SWP. Following their approval, preparation Y was proposed to and accepted by the Expert Committee on Biological Standardization of the World Health Organization to be the 1st IS for FXIII plasma with an activity potency of 0.91 IU per ampoule and an antigen potency of 0.93 IU per ampoule.


Assuntos
Fator XIII/normas , Plasma , Comportamento Cooperativo , Fator XIII/imunologia , Humanos , Laboratórios , Reprodutibilidade dos Testes
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