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3.
Bone Marrow Transplant ; 48(9): 1173-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23524639

RESUMO

Primary graft failure (pGF) is associated with considerable morbidity and mortality. Salvage hematopoietic SCT (HSCT) can rescue pGF patients; however, the optimal preconditioning regimen and stem cell source are yet to be determined, particularly in children. In this study, we retrospectively analyzed 102 pediatric patients who received salvage allogeneic HSCT for pGF. Salvage HSCT from matched or one-Ag-mismatched related donors (rMM01) provided superior OS compared with that from two- or three-Ags-mismatched related donors (rMM23) or cord blood transplantation (CBT). CBT showed a trend toward a slightly lower engraftment rate and late engraftment achievement compared with rMM23; however, the OS rate was similar between the two groups (47.6±7.7% for rMM23 and 45.7±8.6% for CBT, at 1 year after salvage HSCT). Multivariate analysis showed that preconditioning regimens with fludarabine or irradiation were associated with a higher engraftment rate and those with alkylating agents were associated with better OS. In conclusion, our results showed that rMM01 was the most suitable donor for salvage HSCT for pediatric pGF, and that CBT was an equally important option compared with rMM23 for patients without rMM01.


Assuntos
Rejeição de Enxerto/cirurgia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Terapia de Salvação/métodos , Condicionamento Pré-Transplante/métodos , Adolescente , Criança , Pré-Escolar , Sobrevivência de Enxerto , Humanos , Lactente , Prognóstico , Fatores de Risco , Taxa de Sobrevida , Transplante Homólogo , Resultado do Tratamento
4.
Bone Marrow Transplant ; 48(5): 657-60, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23103680

RESUMO

We report long-term outcomes of 329 childhood severe aplastic anemia (SAA) patients who underwent hematopoietic SCT (HSCT) from an HLA-matched sibling donor in the Japanese Hematopoietic Cell Transplantation Registry. OS and EFS at 10 years were as high as 89.7+/-1.7% and 85.5+/-2.0%, respectively. Five cases of late malignancies (LM) were identified (malignant peripheral nerve sheath tumor, thyroid carcinoma, colon carcinoma, MDS and hepatoblastoma). Cumulative incidence of LM was 0.8% at 10 years and 2.5% at 20 years, respectively, which was lower than that in previous reports. This low incidence is in keeping with the low occurrence of skin cancer in Japanese population and of acute GVHD in our study group. Radiation-containing conditioning was not significantly associated with the incidence of LM after HSCT probably because of absolute low patient number who developed LM in our series. In terms of LM development after HSCT, low-dose TBI in HSCT for SAA to avoid graft rejection, which is commonly used in Japan, might be tolerable in the Japanese population because of its low incidence.


Assuntos
Anemia Aplástica/cirurgia , Transplante de Células-Tronco Hematopoéticas/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Antígenos HLA/imunologia , Humanos , Lactente , Japão , Masculino , Irmãos , Análise de Sobrevida , Doadores de Tecidos , Resultado do Tratamento
6.
Bone Marrow Transplant ; 46(8): 1057-62, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21042310

RESUMO

We evaluated the efficacy and safety of the conditioning regimen that consisted of TBI and melphalan (L-PAM), followed by hematopoietic SCT (HSCT) in 23 children with advanced hematological malignancies. The median age at HSCT was 9 (range, 2-15) years. The underlying diseases were ALL in 16 patients (5 in CR2, 3 in CR3, 6 in relapse (RP) and 2 in induction failure (IF)), AML in 4 patients (3 in RP and 1 in IF) and non-Hodgkin's lymphoma in 3 patients (1 in CR3, 1 in CR4 and 1 in RP). The stem cell sources were BM for 19 patients and cord blood for 4 patients. All patients received the conditioning regimen that consisted of TBI 12 or 13.2 Gy and L-PAM 210 mg/m(2). In all, 22 patients engrafted on the median of day 16 (range, 10-23). The regimen was well tolerated and common regimen-related toxicities (RRTs) included grade II stomatitis and grade I hepatic toxicity. The cumulative incidences of RP and TRM were 47.6 and 21.5%, respectively. At a median follow-up of 24.4 months, the probability of disease-free survival was 41.0%. The regimen may provide sufficient anti-leukemic effect without increased RRT for advanced pediatric hematological malignancies.


Assuntos
Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Melfalan/uso terapêutico , Condicionamento Pré-Transplante/métodos , Adolescente , Criança , Pré-Escolar , Terapia Combinada , Intervalo Livre de Doença , Feminino , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/radioterapia , Neoplasias Hematológicas/cirurgia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Estudos Retrospectivos , Condicionamento Pré-Transplante/efeitos adversos , Irradiação Corporal Total
7.
Bone Marrow Transplant ; 41(6): 571-7, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18026150

RESUMO

We report the results of a retrospective analysis in 27 pediatric patients who received low-dose MTX as the second-line treatment for steroid-refractory or -dependent acute and chronic GVHD. Between July 2000 and May 2006, 10 patients with aGVHD and 17 with cGVHD were treated with MTX at a dose of 3-10 mg/m(2) weekly. Seven of ten patients (70%) with aGVHD responded well to MTX, thus resulting in the achievement of either a complete response (CR) or a partial response (PR). The dose of prednisone could be reduced to equal to or lower than 1 mg/kg in the responding patients at the end of MTX therapy. The median number of MTX administrations was five (range, 1-7). Ten (58.8%) of seventeen patients with cGVHD achieved CR or PR. The dose of prednisone could be reduced to lower than 0.4 mg/kg in 16 of 17 patients and seven patients could discontinue prednisone. The median duration of MTX administration was 18 months (range, 1-68). The toxicities of grade III to IV occurred in only six patients presenting cytopenias or elevated levels of serum transaminases. Low-dose MTX was tolerable and effective for the steroid-refractory or -dependent GVHD in reducing the dose of steroid without increasing the risk of opportunistic infection.


Assuntos
Doença Enxerto-Hospedeiro/tratamento farmacológico , Imunossupressores/administração & dosagem , Metotrexato/administração & dosagem , Doença Aguda , Adolescente , Criança , Pré-Escolar , Doença Crônica , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/efeitos adversos , Masculino , Metotrexato/efeitos adversos , Prednisona/administração & dosagem , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
8.
Clin Exp Immunol ; 148(3): 450-60, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17374134

RESUMO

Haematopoietic stem cell transplantation (HSCT) is performed for treatment of a broad spectrum of illnesses. Reconstitution of an intact immune system is crucial after transplantation to avoid infectious complications, and above all, the establishment of T cell receptor (TCR) diversity is the most important goal in the procedure. Until recently, little has been known of the mechanism of T cell reconstitution in the very early period after HSCT. In this study, we analysed TCR repertoires sequentially in four patients with severe combined immunodeficiency (SCID) before and after HSCT. In all patients, the TCR repertoires were extremely abnormal before HSCT, whereas after transplantation there was progressive improvement in TCR diversity, based on analysis of the TCR Vbeta repertoire and CDR3 size distributions. Somewhat unexpectedly, there was a significant but transient expansion of TCR diversity 1 month after transplantation in all cases. Clonotypic analysis of TCRs performed in one case showed that many T cell clones shared identical CDR3 sequences at 1 month and that the shared fraction decreased progressively. These results indicate that early expansion of TCR diversity may reflect transient expansion of pre-existing mature T cells from the donor blood, independent of de novo T cell maturation through the thymus.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Imunodeficiência Combinada Severa/imunologia , Imunodeficiência Combinada Severa/terapia , Subpopulações de Linfócitos T/imunologia , Sequência de Aminoácidos , Sequência de Bases , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular , Células Clonais/imunologia , Regiões Determinantes de Complementaridade/genética , Citometria de Fluxo , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Receptores de Antígenos de Linfócitos T alfa-beta/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
10.
Int Arch Occup Environ Health ; 79(1): 22-6, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16047186

RESUMO

OBJECTIVE: To investigate the influence of room temperature on finger blood flow (FBF) change in healthy subjects exposed to short-term grasping of a vibrating handle under different room temperatures. METHODS: FBF was measured using a blood flowmeter in six male subjects on the dorsum of the middle phalanx of third finger in both hands once at the end of every minute for an equal duration of 5 min at pre-exposure, during exposure to grasping of vibrating handle with sinusoidal vibration and after exposure. Vibration was generated with a frequency of 125 Hz and an rms acceleration of 40 m/s(2). Measurements were conducted in four room temperatures of 15+/-1, 20+/-1, 25+/-1 and 30+/-1 degrees C. RESULTS: Compared with the baseline measurements in the exposed hand during grasping of vibrating handle most significant increase in FBF was observed at 15+/-1 degrees C (P<0.001) and least at 30+/-1 degrees C (P<0.05), and after vibration least significant FBF was found at 25+/-1 degrees C (P<0.05). In case of the unexposed hand significant increase in FBF was exhibited at 20+/-1 degrees C (P<0.01) and 30+/-1 degrees C (P<0.01) during vibration, and only at 15+/-1 degrees C (P<0.05) after vibration. CONCLUSIONS: Response in FBF due to grasping of vibrating handle was of different patterns from the baseline measurement under different room temperature conditions in both exposed and unexposed hands and it was influenced by room temperature. Overall, the influence was greater at lower test room temperature, inducing more significant increase in FBF.


Assuntos
Dedos/irrigação sanguínea , Força da Mão , Temperatura , Vibração , Adulto , Ambiente Controlado , Fluxômetros , Humanos , Japão , Masculino
11.
Eur J Appl Physiol ; 94(5-6): 626-32, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15928934

RESUMO

Percentage finger systolic blood pressure (%FSBP) in response to finger cooling is used to assess vascular components of the hand-arm vibration syndrome and the measurement method is under discussion for standardization. It has been suggested that measurement circumstances including room temperature may affect %FSBP. We investigated the effect of room temperature on %FSBP response to finger cooling in healthy subjects. Six healthy male subjects who were medical students volunteered for the study. Multi-channel plethysmograph was used for simultaneous multi-finger FSBP measurements. The examination room was kept at 21 +/- 1 degrees C and 25 +/- 1 degrees C, and the subjects were randomly assigned. Percentage finger systolic blood pressures for the index, middle, ring and little fingers at 15 degrees C and 10 degrees C cuff-water temperatures were calculated. Four-way analysis of variance was performed to determine the independent effect of subject, room temperature, finger and cuff-water temperature factors on %FSBP. The room temperature as an independent factor affecting %FSBP was statistically significant (P < 0.01). From the results, it can be concluded that %FSBP response to finger cooling in healthy subjects may be affected by room temperature. Therefore, room temperature is expected to be controlled when assessing peripheral vascular components of the upper extremities using %FSBP response to finger cooling.


Assuntos
Pressão Sanguínea/fisiologia , Temperatura Baixa , Ambiente Controlado , Dedos/irrigação sanguínea , Dedos/fisiologia , Temperatura Cutânea/fisiologia , Adulto , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto
12.
Bone Marrow Transplant ; 36(4): 307-13, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15968285

RESUMO

In all, 100 unrelated donor bone marrow transplantations (UD-BMT) were performed in our institute between October 1993 and January 2003. Of 93 evaluable patients, 73 patients had hematological malignancy, 13 had nonmalignancy and seven had lymphoproliferative disease. The estimated 9-year event-free survival (EFS) rate was 57.1+/-5.5% in all patients. In the following analyses of the patients with hematological malignancy, the standard group had significantly better EFS than the high-risk group (61.5+/-7.0 vs 35.6+/-9.7%, P=0.02), and the EFS rate of the tacrolimus (FK-506)+methotrexate (MTX)+/-methylprednisolone prophylactic group for graft-versus-host disease was superior to that of the FK-506 without MTX group (75.7+/-8.0 vs 55.8+/-7.6%, P=0.02). When we compared the EFS rates of the FK506+MTX+/-methylprednisolone (mPSL) group and the HLA-matched related donor BMT group in our institute, these were almost similar (75.7+/-8.1 vs 68.4+/-9.3%). Therefore, UD-BMT using FK-506+MTX+/-mPSL is a safe and useful method for children with hematological malignancy who require allogeneic BMT.


Assuntos
Transplante de Medula Óssea/métodos , Doadores de Tecidos , Adolescente , Adulto , Transplante de Medula Óssea/efeitos adversos , Transplante de Medula Óssea/imunologia , Transplante de Medula Óssea/mortalidade , Criança , Pré-Escolar , Intervalo Livre de Doença , Quimioterapia Combinada , Feminino , Rejeição de Enxerto/etiologia , Doença Enxerto-Hospedeiro/induzido quimicamente , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Doenças Hematológicas/complicações , Doenças Hematológicas/mortalidade , Doenças Hematológicas/terapia , Humanos , Lactente , Japão , Masculino , Metotrexato/uso terapêutico , Metilprednisolona/uso terapêutico , Pré-Medicação , Estudos Retrospectivos , Tacrolimo/uso terapêutico , Tacrolimo/toxicidade
13.
Org Lett ; 3(25): 4075-8, 2001 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-11735588

RESUMO

[reaction: see text] An efficient synthesis of the C10-C31 (BCDEF ring) portion of pinnatoxin A has been achieved. The key step is a highly stereoselective construction of the dispiroketal (BCD ring) system employing an intramolecular hetero-Michael reaction of a reversibly formed hemiketal alkoxide through the use of LiOMe.


Assuntos
Alcaloides/síntese química , Toxinas Marinhas/síntese química , Moluscos/química , Compostos de Espiro/síntese química , Alcaloides/química , Animais , Cristalografia por Raios X , Toxinas Marinhas/química , Conformação Molecular , Estrutura Molecular , Compostos de Espiro/química , Estereoisomerismo
14.
Am J Reprod Immunol ; 45(4): 232-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11327550

RESUMO

PROBLEM: The present study assesses the clinical significance of anti-laminin-1 auto-antibodies (auto-Abs) in recurrent miscarriages. METHOD OF STUDY: A total of 207 recurrent aborters with a history of two or more consecutive first-trimester miscarriages were tested for the presence of anti-laminin-1 Abs, beta2-glycoprotein I-dependent anticardiolipin Abs, lupus anticoagulants, anti-DNA Abs, and anti-nuclear Abs, before they had conceived again. Recurrent aborters then were followed up during subsequent pregnancies and their outcomes were evaluated relative to their blood test results prior to pregnancy. RESULTS: Fifty-five (31.1%) women out of 177 recurrent aborters were positive for IgG anti-laminin-1 auto-Abs. The levels of IgG anti-laminin-1 auto-Abs in recurrent aborters were significantly higher than those in healthy pregnant women and in healthy non-pregnant women (P = 0.0043 and 0.0073, respectively). The live birth rate of subsequent pregnancies in IgG anti-laminin-1 auto-Abs-positive recurrent aborters was significantly lower than the IgG anti-laminin-1 auto-Abs-negative recurrent aborters (P = 0.0320). There were no specifically significant relationships observed between IgG anti-laminin-1 auto-Abs and other tested auto-Abs. CONCLUSION: IgG anti-laminin-1 auto-Abs are associated with recurrent miscarriages and the subsequent pregnancy outcome of recurrent aborters.


Assuntos
Aborto Habitual/imunologia , Autoanticorpos/sangue , Imunoglobulina G/sangue , Laminina/imunologia , Aborto Habitual/etiologia , Adulto , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez
15.
J Lipid Res ; 42(5): 697-709, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11352976

RESUMO

beta(2)-Glycoprotein I (beta(2)-GPI) is a major antigen for antiphospholipid antibodies (Abs) present in patients with the antiphospholipid syndrome (APS). We previously reported that beta(2)-GPI specifically binds to oxidized low density lipoprotein (oxLDL), but not to native low density lipoprotein (LDL). In the present study, a ligand specific for beta(2)-GPI, oxLig-1, was purified from the extracted lipids of oxLDL. The structure of oxLig-1 was shown to be identical to that of synthesized 7-ketocholesteryl-9-carboxynonanoate by mass spectroscopy and nuclear magnetic resonance analyses. Both purified and synthesized oxLig-1 were recognized by beta(2)-GPI and subsequently by anti-beta(2)-GPI auto-Abs, either in enzyme-linked immunosorbent assay (ELISA) or in ligand blot analysis. Binding of liposomes containing oxLig-1 (oxLig-1-liposomes) to mouse macrophages, J774A.1 cells, was relatively low, as compared with that of phosphatidylserine (PS)-liposomes. In contrast, binding of oxLig-1-liposomes was enhanced more than 10-fold in the presence of both beta(2)-GPI and an anti-beta(2)-GPI auto-Ab (WB-CAL-1), derived from (NZW x BXSB) F1 mouse, an animal APS model. Anti-beta(2)-GPI auto-Abs derived from APS patients with episodes of arterial thrombosis were detected in ELISA, using a solid phase oxLig-1 complexed with beta(2)-GPI. We suggest that autoimmune atherogenesis linked to beta(2)-GPI interaction with oxLDL and Abs may be present in APS.


Assuntos
Síndrome Antifosfolipídica/complicações , Autoanticorpos/metabolismo , Glicoproteínas/metabolismo , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Animais , Síndrome Antifosfolipídica/fisiopatologia , Arteriosclerose/etiologia , Arteriosclerose/imunologia , Autoanticorpos/imunologia , Linhagem Celular , Endocitose/fisiologia , Ensaio de Imunoadsorção Enzimática , Glicoproteínas/imunologia , Humanos , Ligantes , Lipoproteínas LDL/química , Lipoproteínas LDL/imunologia , Lipossomos/química , Lipossomos/metabolismo , Espectroscopia de Ressonância Magnética , Metilação , Camundongos , Estrutura Molecular , Fosfolipídeos/metabolismo , Trombose/etiologia , Trombose/imunologia , beta 2-Glicoproteína I
16.
Biochem Biophys Res Commun ; 277(2): 436-42, 2000 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-11032741

RESUMO

It is currently thought that chloroplasts of higher plants were derived from endosymbiont oxygenic photosynthetic bacteria (primary endosymbiosis), while Euglena, a photosynthetic protista, gained chloroplasts by secondary endosymbiosis (i.e., incorporation of a photosynthetic eukaryote into heterotrophic eukaryotic host). To examine if the protein transport inside chloroplasts is similar between these organisms, we carried out heterologous protein import experiments with Euglena precursor proteins and spinach chloroplasts. The precursor of a 30-kDa subunit of the oxygen-evolving complex (OEC30) from the thylakoid lumen of Euglena chloroplasts contained the N-terminal signal, stroma targeting, and thylakoid transfer domains. Truncated preOEC30s lacking the N-terminal domain were post-translationally imported into spinach chloroplasts, transported into the thylakoid lumen, and processed to a mature protein. These results showed that protein translocations within chloroplasts in Euglena and higher plants are similar and supported the hypothesis that Euglena chloroplasts are derived from the ancestral Chlorophyta.


Assuntos
Proteínas de Algas , Cloroplastos/metabolismo , Cloroplastos/fisiologia , Euglena/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Complexo de Proteína do Fotossistema II , Proteínas/metabolismo , Proteínas de Protozoários , Trifosfato de Adenosina/farmacologia , Sequência de Aminoácidos , Animais , Evolução Biológica , DNA Complementar/metabolismo , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Euglena/química , Dados de Sequência Molecular , Complexo de Proteínas do Centro de Reação Fotossintética/química , Plasmídeos/química , Biossíntese de Proteínas , Processamento de Proteína Pós-Traducional , Estrutura Terciária de Proteína , Transporte Proteico , Homologia de Sequência de Aminoácidos , Spinacia oleracea/química , Spinacia oleracea/metabolismo , Tilacoides/química , Fatores de Tempo , Transcrição Gênica
18.
Int Immunol ; 12(8): 1183-92, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10917893

RESUMO

Binding of beta(2)-glycoprotein I (beta(2)-GPI)-dependent anticardiolipin antibodies (aCL) derived from antiphospholipid syndrome (APS) is significantly reduced in aCL ELISA due to loss of the phospholipid (PL) binding property of beta(2)-GPI by plasmin treatment. In the present study, the treatment generated a nicked form of beta(2)-GPI and resulted in loss of antigenicity for the autoantibodies detected in ELISA, using an beta(2)-GPI directly adsorbed polyoxygenated carboxylated plate, the assay system of which was not related to PL binding. The nicked form bound to neither Cu(2+)-oxidized low-density lipoprotein (oxLDL) nor to beta(2)-GPI-specific lipid ligands isolated from oxLDL, the result being a complete loss of subsequent binding of anti-beta(2)-GPI autoantibodies. The conformational change in the nicked domain V was predicted from its intact structure determined by an X-ray analysis (implemented in Protein Data Bank: 1C1Z), molecular modeling and epitope mapping of a monoclonal anti-beta(2)-GPI antibody, i.e. Cof-18, which recognizes the related structure. The analysis revealed that novel hydrophobic and electrostatic interactions appeared in domain V after the cleavage, thereby affecting the PL binding of beta(2)-GPI. Such a conformational change may have important implications for exposure of cryptic epitopes located in the domains such as domain IV.


Assuntos
Fibrinolisina/metabolismo , Glicoproteínas/química , Sequência de Aminoácidos , Anticorpos Anticardiolipina/metabolismo , Anticorpos Monoclonais/imunologia , Reações Antígeno-Anticorpo/efeitos dos fármacos , Ligação Competitiva , Sequência Consenso , Cobre/farmacologia , Ensaio de Imunoadsorção Enzimática , Epitopos/química , Epitopos/imunologia , Fibrinolisina/farmacologia , Glicoproteínas/imunologia , Glicoproteínas/metabolismo , Humanos , Ligantes , Lipoproteínas LDL/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica/efeitos dos fármacos , Conformação Proteica/efeitos dos fármacos , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Especificidade por Substrato , beta 2-Glicoproteína I
19.
J Protein Chem ; 19(8): 649-62, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11307949

RESUMO

Hemoglobin A2 (alpha2delta2), which is present at low concentration (1-2%) in the circulating red cells of normal individuals, has two important features that merit its study, i.e., it inhibits polymerization of sickle HbS and its elevated concentration in some thalassemias is a useful clinical diagnostic. However, reports on its functional properties regarding O2 binding are conflicting. We have attempted to resolve these discrepancies by expressing, for the first time, recombinant hemoglobin A2 and systematically studying its functional properties. The construct expressing HbA2 contains only alpha and delta genes so that the extensive purification required to isolate natural HbA2 is circumvented. Although natural hemoglobin A2 is expressed at low levels in vivo, the amount of recombinant alpha2delta2 expressed in yeast is similar to that found for adult hemoglobin A and for fetal hemoglobin F when the alpha + beta or the alpha + gamma genes, respectively, are present on the construct. Recombinant HbA2 is stable, i.e., not easily oxidized, and it is a cooperative functional hemoglobin with tetramer-dimer dissociation properties like those of adult HbA. However, its intrinsic oxygen affinity and response to the allosteric regulators chloride and 2,3-diphosphoglycerate are lower than the corresponding properties for adult hemoglobin. Molecular modeling studies which attempt to understand these properties of HbA2 are described.


Assuntos
Hemoglobina A2/metabolismo , Sequência de Aminoácidos , Biopolímeros , Hemoglobina A2/química , Hemoglobina A2/genética , Dados de Sequência Molecular , Oxigênio/metabolismo , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/metabolismo , Análise Espectral
20.
Cancer ; 86(3): 533-7, 1999 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10430264

RESUMO

BACKGROUND: When skeletal metastasis is the presenting problem and the primary site is occult, there is a need to identify the primary site as soon as possible. However, the search for the primary tumor is often time-consuming and difficult. The purpose of this study was to analyze the efficacy of particular diagnostic approaches and to devise an efficient and optimal diagnostic strategy. METHODS: Among 213 patients with skeletal metastasis treated between 1990 and 1996 were 64 in whom skeletal lesions were the first manifestation of malignancy. The authors retrospectively analyzed both the final diagnosis and the process by which it was made in these 64 cases. RESULTS: The primary cancer was identified antemortem in 56 (88%) of the 64 patients by examination and in 3 patients at autopsy. Lung carcinoma, the most frequently observed primary lesion, was identified in 23 patients. Other primary lesions were prostate carcinoma in 11 patients, breast carcinoma in 5, and hepatocellular carcinoma in 5. The primary malignancy was not determined in 5 patients. Thoracic and abdominal computed tomography (CT) scans were useful, especially in the diagnosis of patients with lung, hepatocellular, renal cell, and pancreatic carcinomas. Tumor markers were abnormally elevated in 73% of patients with carcinomas. CONCLUSIONS: Although thoracic and abdominal CT scans were useful, examination of the gastrointestinal tract and pelvic CT scan seldom revealed the primary lesion and therefore should not be performed as an initial routine study in the absence of abdominal symptoms. Tumor markers are useful in differentiating carcinoma from hematologic malignancy and primary bone tumor.


Assuntos
Neoplasias Ósseas/secundário , Neoplasias Primárias Desconhecidas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Neoplasias Ósseas/sangue , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Desconhecidas/sangue , Neoplasias Primárias Desconhecidas/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
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