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1.
Scand J Rheumatol ; 49(2): 96-104, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31578102

RESUMO

Objective: Recent studies have provided new insights into the role of lymph nodes (LNs) in rheumatoid arthritis (RA). The aim of this study was to evaluate the metabolic activity of the axillary LNs in relation to that of the upper limb joints and the clinical assessment of disease activity in RA patients treated with biologic therapies.Method: 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT) scans were acquired for 64 patients with RA at baseline and after 6 months of biologic therapy, and the patients' clinical status was evaluated. The maximum standardized uptake value (SUVmax), metabolic active volume, and total lesion glycolysis (TLG) were used to assess glucose metabolism in the LNs and 12 joints. Clinical evaluations included serum markers and the Disease Activity Score based on 28-joint count-erythrocyte sedimentation rate (DAS28-ESR).Results: Changes in the SUVmax and TLG for the axillary LNs correlated significantly with those of the ipsilateral wrist joints. There was a positive correlation between the changes in the three metabolic parameters of the axillary LNs and the changes in disease activity after treatment. After 6 months of biologic therapy, all metabolic parameters for the axillary LNs in patients with a DAS28-ESR < 3.2 were significantly lower than those of patients with a DAS28-ESR ≥ 3.2.Conclusion: A relationship between the glucose metabolism of the axillary LNs and the ipsilateral wrist joints was demonstrated by the 18F-FDG-PET/CT parameters. The metabolic activity and active volume of axillary LNs may reflect the therapeutic response to the biologic treatment of RA.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Fluordesoxiglucose F18 , Linfonodos/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Receptores de Interleucina-6/antagonistas & inibidores , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto , Idoso , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/metabolismo , Axila , Feminino , Glucose/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Articulação do Punho/metabolismo
2.
Diabet Med ; 35(3): 376-380, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29247561

RESUMO

AIM: To examine the contribution of PTPN2 coding variants to the risk of childhood-onset Type 1A diabetes. METHODS: PTPN2 mutation analysis was carried out for 169 unrelated Japanese people with childhood-onset Type 1A diabetes. We searched for coding variants that were absent or extremely rare in the general population and were scored as damaging by multiple in silico programs. We performed mRNA analysis and three-dimensional structural prediction of the detected variants, when possible. We also examined possible physical links between these variants and previously reported risk SNPs as well as clinical information from variant-positive children. RESULTS: One frameshift variant (p.Q286Yfs*24) and two probably damaging missense substitutions (p.C232W and p.R350Q) were identified in one child each. Of these, p.Q286Yfs*24 and p.C232W were hitherto unreported, while p.R350Q accounted for 2/121,122 alleles of the exome datasets. The p.Q286Yfs*24 variant did not encode stable mRNA, and p.C232W appeared to affect the structure of the tyrosine-protein phosphatase domain. The three variants were physically unrelated to known risk SNPs. The variant-positive children manifested Type 1A diabetes without additional clinical features and invariably carried risk human leukocyte antigen alleles. CONCLUSIONS: The results provide the first indication that PTPN2 variants contribute to the risk of Type 1A diabetes, independently of known risk SNPs. PTPN2 coding variants possibly induce non-specific Type 1A diabetes phenotypes in individuals with human leukocyte antigen-mediated disease susceptibility. Our findings warrant further validation.


Assuntos
Diabetes Mellitus Tipo 1/genética , Mutação da Fase de Leitura/genética , Mutação de Sentido Incorreto/genética , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Adolescente , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença/genética , Antígenos HLA/genética , Humanos , Lactente , Masculino , Fases de Leitura Aberta/genética , Polimorfismo de Nucleotídeo Único/genética , RNA Mensageiro/genética
3.
J Periodontal Res ; 53(5): 750-761, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29687476

RESUMO

BACKGROUND AND OBJECTIVE: Epithelial cells derived from different regions exhibit marked differences in their differentiation capacity, allowing them to provide a suitable protective barrier. We aimed to clarify the role of peptidylarginine deiminase (PAD) in modifying the key epidermal proteins filaggrin (FLG) and keratin 1 (K1) during stratification of the rat palate and buccal mucosa. MATERIAL AND METHODS: We performed immunofluorescence, immunoblotting, PAD activity assays and 2-dimensional electrophoresis, and developed an organotypic culture model. RESULTS: PAD1 expression was highest in the palate, whereas PAD2, PAD3 and PAD4 expression was highest in the skin, suggesting the tissue-specific expression of PAD isozymes that leads to differences in calcium dependency. Immunoblotting showed that the FLG monomer, as well as its degradation products and precursor (proFLG), were most abundantly expressed in the skin but had low expression in the palate, whereas only faint proFLG expression was detected in the buccal mucosa. FLG and K1 were colocalized with PAD1 and were likely to be citrullinated in the cornified layers of the skin; this colocalization was not detected on the palatal surface, and dot-like presence of proFLG that might be citrullinated and that of PAD1 were found in the granules of the palate. Organotypic models derived from the rat palate revealed that PAD inhibition reduced the breakdown of FLG, increased its association with K1 together with epithelial compaction, and decreased permeability in a dye permeability assay. Conversely, PAD stimulation had the opposite effects. CONCLUSION: Citrullination is likely a protein modification that plays an important role in maintaining the structure and function of oral cornified mucosa in a way that is distinctly different from that of the skin.


Assuntos
Citrulinação/fisiologia , Mucosa Bucal/enzimologia , Desiminases de Arginina em Proteínas/metabolismo , Animais , Animais Recém-Nascidos , Western Blotting , Eletroforese em Gel Bidimensional , Proteínas Filagrinas , Imunofluorescência , Proteínas de Filamentos Intermediários/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real
4.
Skin Res Technol ; 24(2): 175-179, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29057565

RESUMO

BACKGROUND: Acquired skin hypopigmentation has many etiologies, including autoimmune melanocyte destruction, skin aging, inflammation, and chemical exposure. Distinguishing lesions from normally pigmented skin is clinically important to precisely assess disease severity. However, no gold standard assessment method has been reported. We aimed to investigate whether spectrophotometers are useful for assessing vitiligo and rhododendrol (4-(4-hydroxyphenol)-2-butanol) (Rhododenol® )-induced leukoderma disease severity by quantifying skin color. METHODS: Mexameter® MX18 and CM-700d spectrophotometer were used for assessing vitiligo/leukoderma by measuring melanin index, L*a*b* color space, and ΔE*ab value, which represents the color difference between two subjects and is calculated by the values of L*a*b*. RESULTS: MX18 and CM-700d can quantitatively distinguish vitiligo/leukoderma from normally pigmented skin based on melanin index. CM-700d consistently quantified the color of vitiligo/leukoderma lesions and surrounding normally pigmented skin in L*a*b* color spaces and ΔE*ab. ΔE*ab is well correlated with melanin index and clinical appearance. CONCLUSION: ΔE*ab has been frequently used in aesthetic dentistry; however, current study is the first to use it in the measurement of skin color. ΔE*ab seems to be a useful parameter to evaluate the color contrast between vitiligo/leukoderma and surrounding normally pigmented skin and can be used to evaluate disease severity and patient's quality of life.


Assuntos
Hipopigmentação/induzido quimicamente , Pigmentação da Pele/fisiologia , Vitiligo/patologia , Adulto , Feminino , Humanos , Hipopigmentação/patologia , Masculino , Melaninas/metabolismo , Pessoa de Meia-Idade , Espectrofotometria
7.
J Periodontal Res ; 49(6): 703-10, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24329962

RESUMO

BACKGROUND AND OBJECTIVE: Keratinization of the oral mucosa, such as the gingiva, has been shown to be important for periodontal health. Caspase-14 is a protease that plays a role in keratinization of the epidermis. The objective of this study was to investigate whether the expression of caspase-14 is intimately linked with keratinization and to examine the effect of the main component of green tea on the improvement of keratinization in rat oral mucosal preparations. MATERIAL AND METHODS: Histological and immunohistochemical analyses and quantitative mRNA measurements of caspase-14 and its substrate filaggrin were performed using different types of rat epithelial tissue and organotypic reconstruction culture models derived from epithelial cells and fibroblasts taken from the rat oral mucosa. RESULTS: In the skin, palate, buccal mucosa and esophagus, the degree of keratinization appeared to be associated with expression of cytokeratin 10. The relative protein and mRNA expression levels of caspase-14 and filaggrin were consistent with the degree of keratinization in the following order: skin > palate > buccal mucosa > esophagus. The culture models of palatal and buccal mucosa retained a stratified epithelial structure. Expression of caspase-14 appeared to be stronger in the palatal model than in the buccal model. Remarkably, epigallocatechin-3-gallate (EGCG) improved the localization of cytokeratins and increased the expression of caspase-14 and filaggrin. This expression was more intense in the palatal model than in the buccal model, indicating that both models maintain the intrinsic properties of keratinization of the mucosa from where the cultured cells were derived. CONCLUSIONS: These results suggest that keratinization is closely associated with expression of caspase-14 and filaggrin. Our reconstruction models are promising tools for drug evaluation and show that EGCG is beneficial for improving both keratinization and expression of the linked protease in the oral mucosa.


Assuntos
Caspase 14/análise , Proteínas de Filamentos Intermediários/análise , Mucosa Bucal/química , Fosfoproteínas/análise , Animais , Animais Recém-Nascidos , Caspase 14/efeitos dos fármacos , Catequina/análogos & derivados , Catequina/farmacologia , Técnicas de Cultura de Células , Células Epiteliais/química , Epitélio/química , Esôfago/citologia , Fibroblastos/química , Proteínas Filagrinas , Proteínas de Filamentos Intermediários/efeitos dos fármacos , Queratina-10/análise , Queratina-10/efeitos dos fármacos , Queratinas , Modelos Animais , Palato/citologia , Inibidores de Proteases/farmacologia , Ratos , Ratos Wistar , Pele/citologia , Técnicas de Cultura de Tecidos
10.
J Appl Microbiol ; 115(1): 61-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23594273

RESUMO

AIM: To characterize novel multiple bacteriocins produced by Lactobacillus sakei D98. METHODS AND RESULTS: Lactobacillus sakei D98 isolated from Shubo (rice malt) produced at least three bacteriocins. Using three purification steps, three novel antimicrobial peptides termed sakacin D98a, sakacin D98b and sakacin D98c were purified from the culture supernatant. Amino acid and DNA sequencing analysis revealed that the sakacins D98a, D98b and D98c are novel class IIa-like or class IId bacteriocins. In particular, sakacin D98b has a variant pediocin-box sequence, YANGVXC (with Ala instead of Gly), and a different location for the disulfide bridge (Cys(11) and Cys(18)) from that found in other class IIa bacteriocins. CONCLUSIONS: Three novel bacteriocins were identified from Lactobacillus sakei D98. Their antimicrobial spectra and intensities indicate that these sakacins would have different modes of action. In addition, sakacin D98b showed low inhibitory activity against Listeria, probably due to the differences in amino acids and position of the disulfide bridge compared with the other class IIa bacteriocins. SIGNIFICANCE AND IMPACT OF STUDY: Sakacins D98a and D98c are novel bacteriocins belonging to class IId bacteriocins. On the other hand, sakacin D98b, a class IIa-like bacteriocin, has a unique internal structure and activity spectrum.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bacteriocinas/química , Bacteriocinas/farmacologia , Lactobacillus/metabolismo , Sequência de Aminoácidos , Antibacterianos/biossíntese , Bacteriocinas/biossíntese , Sequência de Bases , Dissulfetos/química , Dados de Sequência Molecular , Análise de Sequência de DNA
11.
Gene Ther ; 18(9): 857-66, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21490680

RESUMO

In vitro culture systems of human myogenic cells contribute greatly to elucidation of the molecular mechanisms underlying terminal myogenic differentiation and symptoms of neuromuscular diseases. However, human myogenic cells have limited ability to proliferate in culture. We have established an improved immortalization protocol for human myogenic cells derived from healthy and diseased muscles; constitutive expression of mutated cyclin-dependent kinase 4, cyclin D1 and telomerase immortalized human myogenic cells. Normal diploid chromosomes were preserved after immortalization. The immortalized human myogenic cells divided as rapidly as primary human myogenic cells during the early passages, and underwent myogenic, osteogenic and adipogenic differentiation under appropriate culture conditions. The immortalized cells contributed to muscle differentiation upon xenotransplantation to immunodeficient mice under conditions of regeneration following muscle injury. We also succeeded in immortalizing cryopreserved human myogenic cells derived from Leigh disease patients following primary culture. Forced expression of the three genes shortened their cell cycle to < 30 h, which is similar to the doubling time of primary cultured human myogenic cells during early passages. The immortalization protocol described here allowed human myogenic cells to recapture high proliferation activity without compromising their differentiation potential and normal diploidy.


Assuntos
Linhagem Celular Transformada , Ciclina D1/genética , Quinase 4 Dependente de Ciclina/genética , Células Satélites de Músculo Esquelético/fisiologia , Animais , Ciclo Celular , Diferenciação Celular , Divisão Celular , Humanos , Doença de Leigh/genética , Camundongos , Mutação , Osteogênese
12.
Vet Pathol ; 48(5): 970-4, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20971945

RESUMO

A case of cardiac hamartoma in a 2-month-old squirrel monkey is reported. The monkey showed a loss of appetite and died suddenly. Microscopically, an encapsulated nodular lesion was found at the right atrial wall. The lesion consisted of irregularly shaped, slender myocytes intermingled with a few fibroblasts and collagen fibers. Neither nuclear atypia nor inflammatory cell infiltrate was seen. The constituting cells had stratified striations in the cytoplasm and reacted immunohistochemically for desmin, indicating the nature of myocytes. Based on the above findings, a diagnosis of cardiac hamartoma was made. This is the first case of cardiac hamartoma in this species.


Assuntos
Hamartoma/veterinária , Cardiopatias/veterinária , Doenças dos Macacos/patologia , Saimiri , Animais , Evolução Fatal , Hamartoma/patologia , Cardiopatias/patologia , Imuno-Histoquímica/veterinária
13.
J Appl Microbiol ; 109(1): 282-91, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20070442

RESUMO

AIM: To characterize novel multiple bacteriocins produced by Leuconostoc pseudomesenteroides QU 15. METHODS AND RESULTS: Leuconostoc pseudomesenteroides QU 15 isolated from Nukadoko (rice bran bed) produced novel bacteriocins. By using three purification steps, four antimicrobial peptides termed leucocin A (ΔC7), leucocin A-QU 15, leucocin Q and leucocin N were purified from the culture supernatant. The amino acid sequences of leucocin A (ΔC7) and leucocin A-QU 15 were identical to that of leucocin A-UAL 187 belonging to class IIa bacteriocins, but leucocin A (ΔC7) was deficient in seven C-terminal residues. Leucocin Q and leucocin N are novel class IId bacteriocins. Moreover, the DNA sequences encoding three bacteriocins, leucocin A-QU 15, leucocin Q and leucocin N were obtained. CONCLUSIONS: These bacteriocins including two novel bacteriocins were identified from Leuc. pseudomesenteroides QU 15. They showed similar antimicrobial spectra, but their intensities differed. The C-terminal region of leucocin A-QU 15 was important for its antimicrobial activity. Leucocins Q and N were encoded by adjacent open reading frames (ORFs) in the same operon, but leucocin A-QU 15 was not. SIGNIFICANCE AND IMPACT OF STUDY: These leucocins were produced concomitantly by the same strain. Although the two novel bacteriocins were encoded by adjacent ORFs, a characteristic of class IIb bacteriocins, they did not show synergistic activity.


Assuntos
Bacteriocinas/química , Bacteriocinas/isolamento & purificação , Leuconostoc/metabolismo , Sequência de Aminoácidos , Sequência de Bases , DNA Bacteriano/genética , Leuconostoc/genética , Dados de Sequência Molecular , Análise de Sequência de DNA , Análise de Sequência de Proteína
14.
Gut ; 58(11): 1504-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19398440

RESUMO

OBJECTIVE: To establish an appropriate steroid treatment regimen for autoimmune pancreatitis (AIP). METHODS: A retrospective survey of AIP treatment was conducted in 17 centres in Japan. The main outcome measures were rate of remission and relapse. RESULTS: Of 563 patients with AIP, 459 (82%) received steroid treatment. The remission rate of steroid-treated AIP was 98%, which was significantly higher than that of patients without steroid treatment (74%, 77/104; p<0.001). Steroid treatment was given for obstructive jaundice (60%), abdominal pain (11%), associated extrapancreatic lesions except the biliary duct (11%), and diffuse enlargement of the pancreas (10%). There was no relationship between the period necessary to achieve remission and the initial dose (30 mg/day vs 40 mg/day) of prednisolone. Maintenance steroid treatment was given in 377 (82%) of 459 steroid-treated patients, and steroid treatment was stopped in 104 patients. The relapse rate of patients with AIP on maintenance treatment was 23% (63/273), which was significantly lower than that of patients who stopped maintenance treatment (34%, 35/104; p = 0.048). From the start of steroid treatment, 56% (55/99) relapsed within 1 year and 92% (91/99) relapsed within 3 years. Of the 89 relapsed patients, 83 (93%) received steroid re-treatment, and steroid re-treatment was effective in 97% of them. CONCLUSIONS: The major indication for steroid treatment in AIP is the presence of symptoms. An initial prednisolone dose of 0.6 mg/kg/day, is recommend, which is then reduced to a maintenance dose over a period of 3-6 months. Maintenance treatment with low-dose steroid reduces but dose not eliminate relapses.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Pancreatite/tratamento farmacológico , Prednisolona/administração & dosagem , Esteroides/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Estudos Retrospectivos , Prevenção Secundária , Resultado do Tratamento
15.
Br J Cancer ; 101(4): 598-604, 2009 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-19638976

RESUMO

BACKGROUND: It has been reported that treatment with uracil-tegafur (UFT) has shown significantly better survival and relapse-free survival (RFS) than surgery alone. Therefore, we compared UFT with a combination therapy of cyclophosphamide, methotrexate, and fluorouracil (CMF) in patients who had undergone curative surgery for axillary lymph node-positive breast cancer. METHODS: A total of 377 node-positive patients with stage I, II, or IIIA disease were registered from September 1996 through July 2000 and were randomly assigned to either 6 cycles of CMF or 2 years of UFT. In both arms, tamoxifen (TAM) was concurrently administered for 2 years. The primary end point in this study was the non-inferiority of UFT to CMF. RESULTS: No statistically significant difference between the two groups was observed with regard to the 5-year RFS rate (72.2% in the UFT and 76.3% in the CMF). Adverse event profiles differed between the two groups, with a significantly lower incidence of leukopenia and anaemia in the UFT group, as well as anorexia, nausea/vomiting, stomatitis, and alopecia, which have implications for quality of life. CONCLUSION: UFT administered in combination with TAM holds promise in the treatment of lymph node-positive early breast cancer. On stratified analysis, the recurrence rate in the UFT group was found to be better in oestrogen receptor (ER)-positive patients. Tegafur-based treatment should be evaluated by a prospective randomised trial conducted in ER-positive patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/terapia , Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Hormonais/efeitos adversos , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Terapia Combinada , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Metástase Linfática/patologia , Mastectomia , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Taxa de Sobrevida , Tamoxifeno/administração & dosagem , Tamoxifeno/efeitos adversos , Tegafur/administração & dosagem , Tegafur/efeitos adversos , Uracila/administração & dosagem , Uracila/efeitos adversos
16.
Science ; 269(5227): 1092-5, 1995 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-17755532

RESUMO

A survey of hydrothermal activity along the superfast-spreading (approximately 150 millimeters per year) East Pacific Rise shows that hydrothermal plumes overlay approximately 60 percent of the ridge crest between 13 degrees 50' and 18 degrees 40'S, a plume abundance nearly twice that known from any other rige portion of comparable length. Plumes were most abundant where the axial cross section is inflated and an axial magma chamber is present. Plumes with high ratios of volatile ((3)He, CH(4), and H(2)S) to nonvolatile (Mn and Fe) species marked where hydrothermal circulation has been perturbed by recent magmatic activity. The high proportion of volatile-rich plumes observed implies that such episodes are more frequent here than on slower spreading ridges.

17.
Horm Metab Res ; 41(4): 333-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19048456

RESUMO

Pheochromocytomas are tumors that may produce a variety of substances in addition to catecholamines. To date, among several cases of systemic inflammatory syndrome associated with interleukin-6 (IL-6) secretion, IL-6-producing pheochromocytomas, have been reported. However, the mechanism underlying IL-6 oversecretion in these cases has not yet been clarified. This report describes a patient with pheochromocytoma who exhibited pyrexia and marked inflammatory signs including C-reactive protein elevation. The inflammatory symptoms were easily controlled by the administration of loxoprofen, a nonsteroidal anti-inflammatory drug. The plasma concentration of IL-6 and 11-d-TXB(2), a stable metabolite of thromboxane A(2) (TXA(2)), were significantly elevated in parallel with an elevation of norepinephrine in the samples obtained by selective venous sampling. A left adrenalectomy was performed, and the acute inflammatory symptoms naturally diminished without loxoprofen. Cultured tumor cells obtained from the resected specimen spontaneously released IL-6, and indomethacin inhibited the IL-6 release. According to a cDNA microarray analysis, mRNA of protein kinase C-delta (PKC-delta), prostaglandin D synthase, and arachidonate release-relating enzymes were significantly overexpressed in the tumor tissue in comparison to the adjacent nontumor tissue. The constitutive phosphorylation of PKC-delta was observed in the tumor tissue. These results strongly suggest that the systemic inflammatory syndrome in IL-6-producing pheochromocytoma, at least in part, is caused by the overexpression of PKC-delta, resulting in an excess of arachidonate derivatives such as prostaglandins.


Assuntos
Expressão Gênica , Interleucina-6/sangue , Feocromocitoma/genética , Feocromocitoma/imunologia , Proteína Quinase C-delta/genética , Idoso , Feminino , Humanos , Interleucina-6/imunologia , Feocromocitoma/sangue , Feocromocitoma/cirurgia , Proteína Quinase C-delta/imunologia , Células Tumorais Cultivadas
18.
J Dent Res ; 87(8): 762-6, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18650549

RESUMO

The flexural strength of Type I collagen, the major organic component of human dentin, increases with heat. We hypothesized that human dentin can be strengthened by heating, which may help prevent fracture of non-vital teeth after restoration. Beam-shaped dentin specimens were obtained from the crowns of human third molars. The dentinal tubular orientations were arranged to run parallel or perpendicular to loading surfaces. The flexural and microtensile strengths of dentin in the parallel specimens were 2- to 2.4-fold greater after being heated between 110 degrees C and 140 degrees C for 1 hr. The stress intensity factors at fracture also increased after specimens were heated. The x-ray diffraction analyses suggested that shrinking of the lateral packing of the collagen triple-helices from 14 A to 11 A was the probable cause of the strengthening of heated dentin. We conclude that heat treatment strengthens human dentin.


Assuntos
Análise do Estresse Dentário , Dentina/química , Temperatura Alta , Dente Molar/química , Análise de Variância , Dessecação , Humanos , Técnicas In Vitro , Estresse Mecânico , Resistência à Tração
19.
Clin Nephrol ; 69(2): 107-13, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18218304

RESUMO

BACKGROUND/METHODS: The presence or absence of hypothyroidism was assessed in 152 consecutive Japanese patients with end-stage renal disease on hemodialysis. Eight patients who had undergone treatment for thyroid disease before starting hemodialysis therapy, and 3 patients with amyloidosis due to rheumatoid arthritis were excluded. RESULTS: Of the remaining 141 hemodialysis patients, 14 (9.9%) (9 males and 5 females, aged 69.1 A+/- 8.8 years with a mean duration of hemodialysis of 69 A+/- 51 months) were in a hypothyroid state, defined as a thyroid-stimulating hormone (TSH) level > 5 mU/l. Antithyroid peroxidase antibodies were positive in only 1 of the 14 patients, while antithyroglobulin antibodies were negative in all of these patients. After iodide restriction, the serum TSH level decreased in all the patients from a mean of 16.49 A+/- 22.80 to 4.44 A+/- 3.35 mU/l after 1 month, 4.25 A+/- 2.24 mU/l after 2 months and 3.97 A+/- 2.22 mU/l after 3 months. The 3 months of iodide restriction were also associated with decreases in systolic blood pressure (142 A+/- 19 to 125 A+/- 16 mmHg, p < 0.05), diastolic blood pressure (79 A+/- 13 to 72 A+/- 9 mmHg, p < 0.05) and thyroid gland volume estimated by ultrasonography (13.7 A+/- 6.3 to 11.6 A+/- 5.2 ml, p < 0.05). CONCLUSION: A high prevalence of reversible primary hypothyroidism was found in end-stage renal disease patients on hemodialysis. Retention of excess iodide may be the mechanism responsible for reversible hypothyroidism rather than immunological perturbations. It is, therefore, recommended to attempt iodide restriction before starting l-thyroxine replacement therapy.


Assuntos
Hipotireoidismo/epidemiologia , Falência Renal Crônica/terapia , Diálise Renal/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/complicações , Japão/epidemiologia , Falência Renal Crônica/complicações , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Glândula Tireoide/diagnóstico por imagem , Tireotropina/sangue , Ultrassonografia
20.
J Clin Invest ; 92(1): 54-61, 1993 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7686924

RESUMO

We have developed two different models of tumor angiogenesis by human brain tumors: one being tube formation by bovine aortic endothelial (BAE) cells cocultured with tumor cells in vitro, and other being in vivo angiogenesis in mice when tumor cells are transplanted into the dorsal sac. We investigated whether tube formation could be induced in BAE cells in type I collagen gel when these cells were cocultured with seven human glioma cell lines. Four of the seven glioma cell lines, which had high levels of basic fibroblast growth factor (bFGF) mRNA, induced tube formation by BAE cells. The tube formation was blocked by coadministration of anti-bFGF antibody. In in vivo model system of tumor angiogenesis in mice, these four cell lines were highly angiogenic. In contrast, with the other three glioma cell lines, which had poor expression of bFGF, BAE cells showed no apparent tube formation. These three cell lines did not efficiently develop capillary networks in mice. The results demonstrated a correlative relationship in the tubulogenesis of BAE cells, bFGF mRNA levels and angiogenesis in mice. The present study with two model systems of tumor angiogenesis suggests that the angiogenesis of some human glioma cell lines is mediated by bFGF, possibly via paracrine control.


Assuntos
Endotélio Vascular/crescimento & desenvolvimento , Glioma/irrigação sanguínea , Neovascularização Patológica , Animais , Fator 2 de Crescimento de Fibroblastos/fisiologia , Expressão Gênica , Substâncias de Crescimento/genética , Humanos , Técnicas In Vitro , Camundongos , Morfogênese , Transplante de Neoplasias , RNA Mensageiro/genética , Fator de Crescimento Transformador alfa/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Células Tumorais Cultivadas
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