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1.
J Hand Surg Eur Vol ; 33(5): 557-60, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18662960

RESUMO

There are only three reports of the surgical outcomes of flexor tendon tenolysis after phalangeal fractures. The fracture type, the time to mobilisation following injury and the time between the injury and tenolysis did not affect the results of tenolysis. The outcome only correlated significantly to the total passive range of motion before tenolysis.


Assuntos
Falanges dos Dedos da Mão/lesões , Fraturas Ósseas/patologia , Tendinopatia/cirurgia , Adolescente , Adulto , Estudos de Coortes , Feminino , Fraturas Ósseas/complicações , Fraturas Ósseas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Estudos Retrospectivos , Tendinopatia/etiologia , Tendinopatia/patologia , Aderências Teciduais/etiologia , Aderências Teciduais/patologia , Aderências Teciduais/cirurgia , Resultado do Tratamento , Adulto Jovem
2.
J Bone Joint Surg Br ; 88(10): 1336-40, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17012424

RESUMO

We compared the results ten years after an inverted V-shaped high tibial osteotomy with those of a historical series of conventional closing-wedge osteotomies. The closing-wedge series consisted of 56 knees in 51 patients with a mean follow-up of 11 years (10 to 15). The inverted V-shaped osteotomy was evaluated in 48 knees in 43 patients at a mean follow-up of 14 years (10 to 19). All the patients were scored using the Japanese Orthopaedic Association rating scale for osteoarthritis of the knee and radiological assessment. The pre-operative grade of osteoarthritis was similar in both groups. Post-operatively, the knee function score was graded as satisfactory in 63% (35) of the closing-wedge group but in 89% (43) of the inverted V-shaped osteotomy group. Post-operative radiological examination showed that delayed union and loss of correction occurred more often after a closing-wedge osteotomy than after an inverted V-shaped procedure. Our study suggests that the inverted V-shaped osteotomy may offer more dependable long-term results than traditional closing-wedge osteotomy.


Assuntos
Osteoartrite do Joelho/cirurgia , Osteotomia/métodos , Tíbia/cirurgia , Idoso , Feminino , Seguimentos , Humanos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/fisiopatologia , Medição da Dor , Complicações Pós-Operatórias , Radiografia , Amplitude de Movimento Articular/fisiologia , Tíbia/diagnóstico por imagem , Resultado do Tratamento
3.
Br J Pharmacol ; 134(7): 1498-504, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11724756

RESUMO

1. We investigated the ability of a newly synthesized sugar derivative, OJ-R9188, [N-(2-tetradecylhexadecanoyl)-O-(L-alpha-fucofuranosyl)-D-seryl]-L-glutamic acid 1-methylamide 5-L-arginine salt, to block binding of selectins to their ligands in vitro and inhibit the infiltration of leukocytes in vivo. 2. OJ-R9188 prevented the binding of human E-, P- and L-selectin-IgG fusion proteins to immobilized sialyl Lewis(x) (sLe(x))-pentasaccharide glycolipid, with IC(50) values of 4.3, 1.3, and 1.2 microM, respectively. 3. In a mouse model of thioglycollate-induced peritonitis, OJ-R9188 at 10 mg kg(-1), i.v. inhibited neutrophil accumulation in the peritoneal cavity. In the IgE-mediated skin reaction, OJ-R9188 at 3 and 10 mg kg(-1), i.v. significantly inhibited extravasation of neutrophils and eosinophils into the inflammatory sites and at 10 mg kg(-1), i.v. also inhibited infiltration caused by picryl chloride-induced delayed-type hypersensitivity in mice. These results suggest that OJ-R9188 may be a useful selectin blocker, with activity against human and mouse E-, P- and L-selectins in vitro and in vivo, and that blocking selectin-sLe(x) binding is a promising strategy for the treatment of allergic skin diseases.


Assuntos
Desoxiguanosina/farmacologia , Dermatite/prevenção & controle , Sequestradores de Radicais Livres/farmacologia , Hipersensibilidade Tardia/prevenção & controle , Selectinas/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Ligação Competitiva/efeitos dos fármacos , Desoxiguanosina/análogos & derivados , Desoxiguanosina/uso terapêutico , Dermatite/imunologia , Dermatite/metabolismo , Dexametasona/farmacologia , Relação Dose-Resposta a Droga , Selectina E/metabolismo , Sequestradores de Radicais Livres/uso terapêutico , Humanos , Hipersensibilidade Tardia/induzido quimicamente , Hipersensibilidade Tardia/metabolismo , Imunoglobulina G/metabolismo , Selectina L/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oligossacarídeos/metabolismo , Selectina-P/metabolismo , Peritonite/induzido quimicamente , Peritonite/metabolismo , Peritonite/prevenção & controle , Cloreto de Picrila/administração & dosagem , Polissacarídeos/farmacologia , Proteínas Recombinantes de Fusão/metabolismo , Antígeno Sialil Lewis X , Tioglicolatos/administração & dosagem
5.
Nature ; 408(6812): 574-8, 2000 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-11117742

RESUMO

Microorganisms have flourished in the oceans since at least 3.8 billion years (3.8 Gyr) ago, but it is not at present clear when they first colonized the land. Organic matter in some Au/U-rich conglomerates and ancient soils of 2.3-2.7 Gyr age has been suggested as remnants of terrestrial organisms. Some 2.7-Gyr-old stromatolites have also been suggested as structures created by terrestrial organisms. However, it has been disputed whether this organic matter is indigenous or exogenic, and whether these stromatolites formed in marine or fresh water. Consequently, the oldest undisputed remnants of terrestrial organisms are currently the 1.2-Gyr-old microfossils from Arizona, USA. Unusually carbonaceous ancient soils--palaeosols--have been found in the Mpumalanga Province (Eastern Transvaal) of South Africa. Here we report the occurrences, elemental ratios (C, H, N, P) and isotopic compositions of this organic matter and its host rocks. These data show that the organic matter very probably represents remnants of microbial mats that developed on the soil surface between 2.6 and 2.7 Gyr ago. This places the development of terrestrial biomass more than 1.4 billion years earlier than previously reported.


Assuntos
Evolução Biológica , Ecossistema , Cianobactérias , Sedimentos Geológicos , África do Sul
6.
J Cell Biol ; 151(2): 209-20, 2000 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-11038170

RESUMO

Keratinocyte proliferation and migration are essential to cutaneous wound healing and are, in part, mediated in an autocrine fashion by epidermal growth factor receptor (EGFR)-ligand interactions. EGFR ligands are initially synthesized as membrane-anchored forms, but can be processed and shed as soluble forms. We provide evidence here that wound stimuli induce keratinocyte shedding of EGFR ligands in vitro, particularly the ligand heparin-binding EGF-like growth factor (HB-EGF). The resulting soluble ligands stimulated transient activation of EGFR. OSU8-1, an inhibitor of EGFR ligand shedding, abrogated the wound-induced activation of EGFR and caused suppression of keratinocyte migration in vitro. Soluble EGFR-immunoglobulin G-Fcgamma fusion protein, which is able to neutralize all EGFR ligands, also suppressed keratinocyte migration in vitro. The application of OSU8-1 to wound sites in mice greatly retarded reepithelialization as the result of a failure in keratinocyte migration, but this effect could be overcome if recombinant soluble HB-EGF was added along with OSU8-1. These findings indicate that the shedding of EGFR ligands represents a critical event in keratinocyte migration, and suggest their possible use as an effective clinical treatment in the early phases of wound healing.


Assuntos
Movimento Celular , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Queratinócitos/fisiologia , Pele/lesões , Cicatrização/fisiologia , Alanina/análogos & derivados , Alanina/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Ácidos Hidroxâmicos/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular , Queratinócitos/citologia , Ligantes , Inibidores de Metaloproteinases de Matriz , Camundongos , Camundongos Endogâmicos BALB C , Inibidores de Proteases/farmacologia
7.
Skeletal Radiol ; 29(12): 717-20, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11271554

RESUMO

The authors report a case of bilateral popliteal amyloidoma causing stenosis of the popliteal artery and vein. This patient had been treated with hemodialysis for 26 years. The diagnosis was made with MR angiography. A popliteal tumor of the right knee was resected surgically and the histologic examination showed deposition of amyloid. After resecting the popliteal tumor, the severe leg pain and intermittent claudication improved. This report suggests that popliteal amyloid tumors should be considered in a patient undergoing long-term hemodialysis who complains of leg pain and intermittent claudication.


Assuntos
Amiloidose/complicações , Arteriopatias Oclusivas/complicações , Isquemia/etiologia , Perna (Membro)/irrigação sanguínea , Artéria Poplítea , Diálise Renal/efeitos adversos , Adulto , Amiloidose/diagnóstico , Arteriopatias Oclusivas/diagnóstico , Doença Crônica , Diagnóstico Diferencial , Humanos , Isquemia/diagnóstico , Perna (Membro)/patologia , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Masculino , Síndrome Nefrótica/terapia , Artéria Poplítea/patologia
8.
Electromyogr Clin Neurophysiol ; 38(3): 147-51, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9637940

RESUMO

We recorded masseter reflex potentials to examine the correlation between the masseter reflex and the muscle stretch reflexes of limbs in 19 patients with olivo-ponto-cerebellar atrophy (OPCA). The patients were subdivided into hyper- (n = 5), normo- (n = 7) and hypo- (n = 7) reflexia groups according to the degrees of the conventional deep tendon jerks in the upper limbs. The masseter reflex potentials, elicited by tapping the chin with a reflex hammer, were recorded from the bilateral masseters using a pair of surface electrodes. The latency of the potentials in the hyporeflexia was significantly longer than in the other groups, while the amplitude of those in the hyperreflexia group was significantly higher than in the other groups. These results indicate that in patients with OPCA the magnitude and latency of the masseter reflex correlates with the status of the muscle stretch reflexes of the limbs in contrast with Friedreich's ataxia where the masseter reflex has been reported to be normal or hyperactive despite hyporeflexia in the limbs.


Assuntos
Músculo Masseter/inervação , Atrofias Olivopontocerebelares/fisiopatologia , Reflexo Anormal/fisiologia , Reflexo de Estiramento/fisiologia , Adulto , Vias Aferentes/fisiopatologia , Idoso , Diagnóstico Diferencial , Eletromiografia , Feminino , Ataxia de Friedreich/diagnóstico , Ataxia de Friedreich/fisiopatologia , Humanos , Masculino , Mesencéfalo/fisiopatologia , Pessoa de Meia-Idade , Atrofias Olivopontocerebelares/diagnóstico , Nervos Periféricos/fisiopatologia , Tempo de Reação/fisiologia
9.
Bioorg Med Chem ; 6(5): 587-93, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9629472

RESUMO

We have developed an effective synthesis of sLe(x) pentasaccharide glycolipid analogue 2. As a part of application of sLe(x) pentasaccharide glycolipid 2 synthesized here, we have investigated the construction of a high-through-put screening system for discovery of selectin blockers. As a result, it was found that compound 2 was a useful ligand for in vitro ELISA assay and could be an important material for high-throughput screening of selectin blockers.


Assuntos
Oligossacarídeos/síntese química , Selectinas/efeitos dos fármacos , Configuração de Carboidratos , Sequência de Carboidratos , Ensaio de Imunoadsorção Enzimática , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Oligossacarídeos/química , Antígeno Sialil Lewis X
10.
J Med Chem ; 40(22): 3534-41, 1997 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-9357520

RESUMO

We have rationally designed a sLe(x) mimetic based on molecular modeling, synthesized type II and type II' beta-turn dipeptides (3a,b), and evaluated their biological profiles both in vitro and in vivo. Against E-selectin-sLe(x) binding, the type II beta-turn dipeptide L-Ser-D-Glu 3a (IC50, 13 microM) and the type II' beta-turn dipeptide D-Ser-L-Glu 3b (IC50, 5.5 microM) were 20-100-fold more potent blockers than sLe(x) (1; IC50, 600 microM) and a 3'-sulfated Le(x) analog (2; IC50, 280 microM). On the other hand, other stereoisomers, such as L-Ser-L-Glu 3c and D-Ser-D-Glu 3d, were very weak blockers, with IC50 > 1000 microM for both 3c,d. Against the P- and L-selectins, despite much different stereochemistry of compounds 3a-d, the dipeptides 3a-d were all more potent blockers than either sLe(x) or compound 2. Interestingly, compound 3b provided significant in vivo efficacy against an immunoglobulin E-mediated skin reaction in a mouse model. These findings indicate that sLe(x) mimetics with type II and type II' beta-turn dipeptides could be useful in the design of an active selectin blocker in vitro and/or in vivo.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Dipeptídeos/química , Mimetismo Molecular , Oligossacarídeos/farmacologia , Selectinas/efeitos dos fármacos , Serina/química , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/uso terapêutico , Desenho de Fármacos , Feminino , Imunoglobulina E/efeitos adversos , Inflamação/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Estrutura Molecular , Oligossacarídeos/química , Antígeno Sialil Lewis X , Estereoisomerismo
11.
J Med Chem ; 40(4): 455-62, 1997 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-9046335

RESUMO

In order to clarify the real ligand structure of L-selectin proposed by Rosen et al., we first synthesized 6-sulfated sLe(x) hexasaccharide ceramide 1, 6'-sulfated sLe(x) hexasaccharide ceramide 2, and 6,6'-disulfated sLe(x) hexasaccharide ceramide 3 and examined their binding avidities for L-selectin. As a result, we found that the 6'-sulfated sLe(x) hexasaccharide ceramides 1-3 have similar binding avidities to L-selectin and their binding to L-selectin appeared somewhat stronger than that of sLe(x). For P-selectin, the sulfated sLe(x) derivatives 1-3 showed a similar avidity to sLe(x). On the other hand, 6-sulfated sLe(x) 2 was recognized to E-selectin and the binding avidity was apparently weak as compared to that of sLe(x) hexasaccharide ceramide. Surprisingly, 6'-sulfated and 6,6'-disulfated sLe(x)s 1 and 3 did not bind to E-selectin at all. We constructed the E-selectin-sLe(x) complex model and investigated the binding mode. Namely, the galactose 6'-position was directed toward the negatively charged residues, Glu80 and Asp100. Our results with E-selectin indicate that the replacement of 6'-OH position from anionic charged group to cationic charged one, e.g., amino groups, could have a marked affect on E-selectin recognition. These results could provide useful information for the drug design of selectin blockers.


Assuntos
Ceramidas/metabolismo , Antígenos do Grupo Sanguíneo de Lewis/metabolismo , Oligossacarídeos/metabolismo , Selectinas/metabolismo , Sulfatos , Animais , Ceramidas/química , Desenho de Fármacos , Selectina E/metabolismo , Ensaio de Imunoadsorção Enzimática , Selectina L/metabolismo , Modelos Químicos , Selectina-P/metabolismo , Ratos , Antígeno Sialil Lewis X , Software , Estereoisomerismo , Relação Estrutura-Atividade
12.
J Med Chem ; 40(3): 362-9, 1997 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-9022803

RESUMO

Through a computer modeling and simulation technique, we investigated the binding mode of a complex of E-selectin-GSC-150, which is a novel selectin blocker. GSC-150 is the 3'-sulfated Lewis X derivative with a long, branched alkyl chain. Initial attempts to construct a model for E-selectin-GSC-150 complex were performed based on a previously reported model of E-selectin-sialyl Lewis X (sLex) complex [Kogan, T.P.; Revelle, B.M.; Tapp, S.; Scott, D.; Beck, P.J.J. Biol. Chem. 1995, 270, 14047-14055]. In our model, the carbohydrate portion of GSC-150 interacted with the protein in a similar manner as that of sLex reported previously. Interestingly, each of the branched alkyl chains extended on the surface of E-selectin and interacted with two different hydrophobic portions. One of these hydrophobic portions consists of Tyr44, Pro46, and Tyr48. Another portion forms a shallow cavity, and it consists of Ala9, Leu114, and the alkyl moieties of the side chains of Lys111, Lys112, and Lys113. A subsequent 200-ps molecular dynamics simulation in solution revealed that the interactions involved in the sugar portion of the ligand were relatively weak, whereas the hydrophobic interactions involved in the branched alkyl chains were fairly stable in solution. These results suggest that the branched alkyl chain serves as an "anchor" for the tight binding of GSC-150 on the surface of E-Selectin. This is the first attempt to evaluate the dynamics of E-Selectin-ligand interactions in solution, and it sheds light on the nature of ligand recognition by selectins.


Assuntos
Selectina E/metabolismo , Glicoesfingolipídeos/metabolismo , Oligossacarídeos/metabolismo , Sequência de Carboidratos , Simulação por Computador , Glicoesfingolipídeos/química , Lectinas/metabolismo , Ligantes , Modelos Moleculares , Conformação Molecular , Dados de Sequência Molecular , Estrutura Molecular , Antígeno Sialil Lewis X , Sulfatos/metabolismo
13.
Geochim Cosmochim Acta ; 61(19): 4115-37, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-11540490

RESUMO

Fifty-eight rock chips from fifteen samples of sedimentary rocks from the Ramah Group (approximately 1.9 Ga) in northeastern Labrador, Canada, were analyzed for major and minor elements, including C and S, to elucidate weathering processes on the Earth's surface about 1.9 Ga ago. The samples come from the Rowsell Harbour, Reddick Bight, and Nullataktok Formations. Two rock series, graywackes-gray shales of the Rowsell Harbour, Reddick Bight and Nullataktok Formations, and black shales of the Nullataktok Formation, are distinguishable on the basis of lithology, mineralogy, and major and trace element chemistry. The black shales show lower concentrations than the graywackes-gray shales in TiO2 (0.3-0.7 wt% vs. 0.7-1.8 wt%), Al2O3 (9.5-20.1 wt% vs. 13.0-25.0 wt%), and sigma Fe (<1 wt% vs. 3.8-13.9 wt% as FeO). Contents of Zr, Th, U, Nb, Ce, Y, Rb, Y, Co, and Ni are also lower in the black shales. The source rocks for the Ramah Group sediments were probably Archean gneisses with compositions similar to those in Labrador and western Greenland. The major element chemistry of source rocks for the Ramah Group sedimentary rocks was estimated from the Al2O3/TiO2 ratios of the sedimentary rocks and the relationship between the major element contents (e.g., SiO2 wt%) and Al2O3/TiO2 ratios of the Archean gneisses. This approach is justified, because the Al/Ti ratios of shales generally retain their source rock values; however, the Zr/Al, Zr/Ti, and Cr/Ni ratios fractionate during the transport of sediments. The measured SiO2 contents of shales in the Ramah Group are generally higher than the estimated SiO2 contents of source rocks by approximately 5 wt%. This correction may also have to be applied when estimating average crustal compositions from shales. Two provenances were recognized for the Ramah Group sediments. Provenance I was comprised mostly of rocks of bimodal compositions, one with SiO2 contents approximately 45 wt% and the other approximately 65 wt%, and was the source for most sedimentary rocks of the Ramah Group, except for black shales of the Nullataktok Formation. The black shales were apparently derived from Provenance II that was comprised mostly of felsic rocks with SiO2 contents approximately 65 wt%. Comparing the compositions of the Ramah Group sedimentary rocks and their source rocks, we have recognized that several major elements, especially Ca and Mg, were lost almost entirely from the source rocks during weathering and sedimentation. Sodium and potassium were also leached almost entirely during the weathering of the source rocks. However, significant amounts of Na were added to the black shales and K to all the rock types during diagenesis and/or regional metamorphism. The intensity of weathering of source rocks for the Ramah Group sediments was much higher than that of typical Phanerozoic sediments, possibly because of a higher PCO2 in the Proterozoic atmosphere. Compared to the source rock values, the Fe3+/Ti ratios of many of the graywackes and gray shales of the Ramah Group are higher, the Fe2+/Ti ratios are lower, and the sigma Fe/Ti ratios are the same. Such characteristics of the Fe geochemistry indicate that these sedimentary rocks are comprised of soils formed by weathering of source rocks under an oxygen-rich atmosphere. The atmosphere about 1.9 Ga was, therefore, oxygen rich. Typical black shales of Phanerozoic age exhibit positive correlations between the organic C contents and the concentrations of S, U, and Mo, because these elements are enriched in oxygenated seawater and are removed from seawater by organic matter in sediments. However, such correlations are not found in the Ramah Group sediments. Black shales of the Ramah Group contain 1.7-2.8 wt% organic C, but are extremely depleted in sigma Fe (<1 wt% as FeO), S (<0.3 wt%), U (approximately l ppm), Mo (<5 ppm), Ni (<2 ppm), and Co (approximately 0 ppm). This lack of correlation, however, does not imply that the approximately 1.9 Ga atmosphere-ocean system was anoxic. Depletion of these elements from the Ramah Group sediments may have occurred during diagenesis.


Assuntos
Atmosfera/química , Sedimentos Geológicos/química , Geologia/métodos , Minerais/análise , Oxigênio/análise , Planeta Terra , Evolução Planetária , Sedimentos Geológicos/análise , Terra Nova e Labrador , Paleontologia
14.
Geology ; 25(9): 858-9, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11540483

RESUMO

The major points of disagreement between Holland and Rye and Ohmoto concern (1) the behavior of ferric iron. (2) the mechanisms of Fe loss. (3) the identification of real paleosols, and (4) the ages of some paleosols.


Assuntos
Atmosfera/química , Compostos Férricos/análise , Sedimentos Geológicos/análise , Ferro/química , Oxigênio/análise , Solo/análise , Evolução Planetária , Sedimentos Geológicos/química , Fenômenos Geológicos , Geologia , Paleontologia , África do Sul , Titânio/química
15.
Geology ; 24(12): 1135-8, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11540480

RESUMO

The loss of Fe from some pre-2.2 Ga paleosols has been considered by previous investigators as the best evidence for a reduced atmosphere prior to 2.2 Ga. I have examined the behavior of Fe in both pre- and post-2.2 Ga paleosols from depth profiles of Fe3+/Ti, Fe2+/Ti, and sigma Fe/Ti ratios, and Fe3+/Ti vs. Fe2+/Ti plots. This new approach reveals a previously unrecognized history of paleosols. Essentially all paleosols, regardless of age, retain some characteristics of soils formed under an oxic atmosphere, such as increased Fe3+/Ti ratios from their parental rocks. The minimum oxygen pressure (PO2) for the 3.0-2.2 Ga atmosphere is calculated to be about 1.5% of the present atmospheric level, which is the same as that for the post-1.9 Ga atmosphere. The loss of sigma Fe, common in paleosol sections of all ages, was not due to a reducing atmosphere, but to reductive dissolution of ferric hydroxides formed under an oxic atmosphere. This reductive dissolution of ferric hydroxides occurred either (1) after soil formation by hydrothermal fluids or (2) during and/or after soil formation by organic acids generated from the decay of terrestrial organic matter. Terrestrial biomass on the early continents may have been more extensive than previously recognized.


Assuntos
Atmosfera/química , Sedimentos Geológicos/análise , Ferro/química , Oxigênio/análise , Solo/análise , Titânio/química , Biomassa , Canadá , Evolução Planetária , Compostos Férricos/análise , Compostos Ferrosos/análise , Sedimentos Geológicos/química , Fenômenos Geológicos , Geologia , Paleontologia , África do Sul
16.
J Med Chem ; 39(10): 2055-9, 1996 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-8642564

RESUMO

As a part of our studies of selectin blockers, we prepared 1-(2-tetradecylhexadecyl)-3'-O-sulfo Le(X) 1 and 1-(2-tetradecylhexadecyl) sLe(X) 2 and examined their inhibitory activities against natural ligand (sLe(X)) binding to E-, P-, and L-selectins. Compounds 1 and 2 were 2 times more potent than the sLe(X) tetrasaccharide toward E-selectin binding and up to 4 times more potent than sLe(X) toward P- and L-selectin binding. Interestingly, compound 1 provided dose-dependent protective effects against an immunoglobulin E-mediated skin reaction in mouse ears. This protective effect was associated with diminished tissue accumulation of neutrophils in the ear (as assessed by myeloperoxidase). These findings indicate that the modification of sLe(X) or 3'-O-sulfo Le(X) with a "branched anchor", a 2-tetradecylhexadecyl group, is useful in the design of a more potent selectin blocker, which has broad inhibitory activities toward all selectins.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Inflamação/tratamento farmacológico , Oligossacarídeos/farmacologia , Selectinas/efeitos dos fármacos , Ésteres do Ácido Sulfúrico/farmacologia , Animais , Anti-Inflamatórios não Esteroides/química , Sequência de Carboidratos , Feminino , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Oligossacarídeos/química , Ésteres do Ácido Sulfúrico/química
17.
J Med Chem ; 39(6): 1339-43, 1996 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-8632441

RESUMO

As part of our studies of selectin blockers, we prepared 1-deoxy-3'-O-sulfo LeX analogs (1-3), 1-deoxy-3'-O-phosphono LeX analogs (4), and 1-deoxy sLeX analogs (5-7), and examined their inhibitory activities against natural ligand (sLeX) binding to E-selectin, P-selectin, and L-selectin. The 1-deoxy sLeX 5 was up to 20 times more potent an inhibitor than the sLeX tetrasaccharide toward P- and L-selectin binding. This indicates that the modification of the 1 or 2 position of sLeX is useful in the design of a more potent selectin blocker.


Assuntos
Selectina E/metabolismo , Selectina L/metabolismo , Antígenos CD15/farmacologia , Selectina-P/metabolismo , Conformação Molecular , Relação Estrutura-Atividade
18.
J Exp Med ; 182(6): 1777-83, 1995 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-7500022

RESUMO

Fas ligand (FasL) is a type II integral membrane protein homologous with tumor necrosis factor (TNF). Recent studies indicate that TNF is processed to yield the soluble cytokine by metalloproteinases at the cell surface of activated macrophages and T cells. In the present study, we investigated whether FasL is also released by metalloproteinases. Treatment with hydroxamic acid inhibitors of matrix metalloproteinases specifically led to accumulation of membrane-type FasL (p40) on the surface of human FasL cDNA transfectants and activated human T cells, as estimated by surface immunofluorescence and immunoprecipitation with newly established anti-human FasL monoclonal antibodies. This surface accumulation of mFasL was associated with the decrease of soluble FasL (p27) in the supernatant as estimated by quantitative ELISA and immunoprecipitation with anti-human FasL monoclonal antibodies. These results indicate that human FasL is efficiently released from the cell surface by metalloproteinases like TNF.


Assuntos
Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Metaloendopeptidases/metabolismo , Animais , Membrana Celular/metabolismo , Células Cultivadas , Proteína Ligante Fas , Humanos , Camundongos , Camundongos Mutantes , Inibidores de Proteases/farmacologia , Processamento de Proteína Pós-Traducional , Solubilidade , Transfecção , Fator de Necrose Tumoral alfa/metabolismo
19.
Ryumachi ; 35(5): 792-801, 1995 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-8594658

RESUMO

MMP-9 degrades type IV collagen, gelatin, type V collagen, and type XI collagen. We measured proMMP-9 and proMMP-9/TIMP-1 complex in sera and joint fluids by sandwich ELISA, and examined immunohistochemically the expression of these proteins in joint tissue from patients with rheumatoid arthritis (RA). ProMMP-9 was purified by the three chromatographic steps from the culture medium of HT1080 cells. Purified proMMP-9 and activated MMP-9 by APMA showed a single band of Mr92000, Mr67000, resectively on gelatin-zymography. We raised two monoclonal antibody colones 2G9, 8G7 against proMMP-9 with BALB/c mice. 2G9 and 8G7 reacted with proMMP-9 on Western blotting, and these clones reacted proMMP-9 and proMMP-9/TIMP-1 complex on sandwich ELISA, specifically. ProMMP-9 concentration in 86 sera (749.4+/-940.2 ng/ml) and 54 joint fluids (4539.9+/-7681.5 ng/ml) from patients with RA was significantly higher than those of patients with osteoarthritis and control. Immunohistochemistry with 2G9 showed that in rheumatoid synovium proMMP-9 localized in neutrophils and monocytes diffusely infiltrated the sublining layer. In addition, osteoclasts in rheumatoid subchondral bone were intensively stained. ProMMP-9 concentration in joint fluids from 39 RA patients was not correlated to stage and class of Steinbrocker and to clinical laboratorial data. But, it was positively correlated to the number of proMMP-9 positive cells in RA synovium (r=0.607) and the score of Roony's diffuse infiltrates of lymphocytes (r=0.720). Our results suggest a role of MMP-9 in joint destraction of RA throughout neutrophils and monocytes, and a regulation of this enzyme by lymphocytes.


Assuntos
Artrite Reumatoide/metabolismo , Colagenases/metabolismo , Líquido Sinovial/química , Adulto , Idoso , Animais , Artrite Reumatoide/etiologia , Feminino , Humanos , Imuno-Histoquímica , Macrófagos , Masculino , Metaloproteinase 9 da Matriz , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Neutrófilos , Líquido Sinovial/citologia
20.
J Biochem ; 117(6): 1218-27, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7490263

RESUMO

An improved combinatorial library system to raise mouse monoclonal antibodies was constructed. PCR primers have been newly designed to optimize the reaction for Pfu DNA polymerase, which has proofreading activity. The phagemid vector (pPDS) is designed to accommodate VH and Vk cDNAs, which had previously been assembled by PCR either in single chain fragment of variable regions (scFv) or Fab form. Antibody cloned in scFv form can be converted to Fab form by substituting the scFv linker of (Gly4Ser)3 with a fragment containing murine CH1 cDNA. This vector will produce soluble Fab in non-amber suppressor cells and allow the shuffling of light chains against a heavy chain. Hybridoma cell lines producing anti-human procollagenase monoclonal antibodies were used as the source of antibody mRNA. Antigen-binding ability of both scFv- and Fab-displaying phage was confirmed by ELISA against human procollagenase. They were also analyzed by DNA sequencing to verify the fidelity of Pfu DNA polymerase and to identify the primer incorporated. The mutation rate was considerably reduced compared to the mutation rate achieved by Taq DNA polymerase. Primers are incorporated into target sequences in most cases.


Assuntos
Anticorpos Monoclonais/genética , Clonagem Molecular , Colagenases/imunologia , Primers do DNA , DNA Polimerase Dirigida por DNA/metabolismo , Precursores Enzimáticos/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Bacteriófagos/genética , Sequência de Bases , Códon/genética , DNA Polimerase Dirigida por DNA/genética , Ensaio de Imunoadsorção Enzimática , Biblioteca Gênica , Vetores Genéticos , Humanos , Fragmentos Fab das Imunoglobulinas/genética , Fragmentos Fab das Imunoglobulinas/imunologia , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Proteínas Recombinantes/genética
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