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1.
Int J Cardiol Cardiovasc Risk Prev ; 19: 200215, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37771606

RESUMO

Background: Hospital-at-Home (HAH) is a valid alternative for in-hospital stay for a wide variety of clinical indications. Occult myocardial injury, associated with acute illness, mainly occurs in patients with a background of non-obstructive coronary disease. The aim of this study was to describe the prevalence of this phenomenon in our HAH population. Methods: A retrospective description and analysis of data collected for patients admitted to the Sheba beyond's HAH services during 14 months. Results: During a period of 14 months (7/10/21-6/12/22), blood troponin measurements were available for 213 patients (median age 78 years, 52% males) hospitalized mainly for infectious causes. The median HS (highly sensitive) troponin level was 7.7 ng/L (IQR = 13.2 ng/L) (the normal upper limit is 12 ng/L) with 31% of all patients demonstrating an abnormally increased troponin level (68/213). Of all patients, 64% had a background diagnosis of a cardiovascular disease (138/213), of whom, 49% had abnormal HS troponin levels (68/138). No patient suffered from acute cardiac function deterioration and no patient died during their hospital-at-home stay. Conclusion: The prevalence of occult myocardial injury amongst elderly patients admitted to hospital-at-home stay for diagnoses other than myocardial infarction is relatively high but it is not associated with worse short-term clinical outcomes.

2.
Eat Weight Disord ; 16(2): e102-12, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21989094

RESUMO

The current study examined associations among sports participation (SP), athletic identity (AI), weight status, and eating pathology, and whether these relations differed by gender. Data come from male and female first-year college students who participated in the Tufts Longitudinal Health Study (TLHS) between 1999-2007 (N=712). Relations among SP, AI, actual and perceived weight statuses, Eating Disorders Inventory (EDI) subscale scores, and indices of body shape concern and restrictive eating were examined with hierarchical ordinary least squares (OLS) regression. Associations between SP and eating pathology among females were moderated by perceived weight status. By contrast, relations between males' EDI subscales scores and SP were moderated by ethnicity, as well as by actual weight status. Our findings support that sports participation alone neither promotes nor protects against eating pathology among males and females.


Assuntos
Imagem Corporal , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Autoimagem , Identificação Social , Esportes/psicologia , Adolescente , Peso Corporal , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Estudos Longitudinais , Masculino , Fatores Sexuais , Estudantes , Inquéritos e Questionários , Universidades , Adulto Jovem
3.
J Thromb Haemost ; 7(12): 2023-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19793187

RESUMO

BACKGROUND: Warfarin affects the synthesis and function of the matrix Gla-protein, a vitamin K-dependent protein, which is a potent inhibitor of tissue calcification. OBJECTIVES: To investigate the incidence of mitral valve calcium (MVC), mitral annular calcium (MAC) and aortic valve calcium (AVC) in patients with non-valvular atrial fibrillation (AF) treated with warfarin vs. no warfarin. PATIENTS AND METHODS: Of 1155 patients, mean age 74 years, with AF, 725 (63%) were treated with warfarin and 430 (37%) without warfarin. The incidence of MVC, MAC and AVC was investigated in these 1155 patients with two-dimensional echocardiograms. Unadjusted logistic regression analysis was conducted to examine the association between the use of warfarin and the incidence of MVC, MAC or AVC. Logistic regression analyses were also conducted to investigate whether the relationship stands after adjustment for confounding risk factors such as age, sex, race, ejection fraction, smoking, hypertension, diabetes, dyslipidemia, coronary artery disease (CAD), glomerular filtration rate, calcium, phosphorus, calcium-phosphorus product, alkaline phosphatase, use of aspirin, beta blockers, angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and statins. RESULTS: There was a significant association between the use of warfarin and the risk of calcification [unadjusted odds ratio = 1.71, 95% CI = (1.34-2.18)]. The association still stands after adjustment for confounding risk factors. MVC, MAC or AVC was present in 473 of 725 patients (65%) on warfarin vs. 225 of 430 patients (52%) not on warfarin (P < 0.0001). Whether this is a causal relationship remains unknown. CONCLUSIONS: Use of warfarin in patients with AF is associated with an increased prevalence of MVC, MAC or AVC.


Assuntos
Valva Aórtica/patologia , Calcinose/induzido quimicamente , Valva Mitral/patologia , Varfarina/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Proteínas de Ligação ao Cálcio/biossíntese , Proteínas de Ligação ao Cálcio/fisiologia , Proteínas da Matriz Extracelular/biossíntese , Proteínas da Matriz Extracelular/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Estudos Retrospectivos , Risco , Fatores de Risco , Varfarina/uso terapêutico , Proteína de Matriz Gla
4.
J Thromb Haemost ; 7(1): 65-71, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18983493

RESUMO

BACKGROUND AND OBJECTIVES: Based on the American College of Chest Physicians 2004 antithrombotic therapy for venous thromboembolism (VTE) and the Eastern Association for the Surgery of Trauma 2002 guidelines, placement of an inferior vena cava (IVC) filter is indicated in patients who either have, or are at high risk for, VTE, but have a contraindication or failure of anticoagulation. Our aim is to compare clinical characteristics and outcomes of patients receiving IVC filters within-guidelines (WG) and outside-of-guidelines (OOG). METHODS: The 558 patients who received an IVC filter were divided into two groups called WG or OOG. The WG group met the criteria described above and the OOG group did not have a contraindication to or a failure of anticoagulation. RESULTS: The WG group had 362 patients and the OOG group had 196 patients. The OOG group had one (0.5%) patient with post-filter pulmonary embolism (PE), two (1%) with IVC thrombosis, and seven (3.6%) with deep vein thrombosis (DVT). The WG group had five (1.4%) patients with post-filter PE, 13 (3.6%) with IVC thrombosis, and 34 (9.4%) with DVT. All patients who developed post-filter PE had a DVT before filter placement, and patients who did not have a prior VTE event were at a significantly lower risk of developing post-filter IVC thrombosis and PE. CONCLUSION: Our data do not support the use of an IVC filter outside of guidelines in patients without prior VTE who can tolerate anticoagulation because of the low risk of developing PE.


Assuntos
Guias de Prática Clínica como Assunto/normas , Embolia Pulmonar/prevenção & controle , Filtros de Veia Cava/estatística & dados numéricos , Tromboembolia Venosa/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Trombose Venosa/complicações , Adulto Jovem
5.
Br J Haematol ; 124(4): 474-80, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14984497

RESUMO

A total of 110 patients, aged 64 years or over, with de novo acute myeloid leukaemia (AML) and white blood cell counts <50 x 109/l were treated with 3 d of cytarabine 1 g/m2 twice daily, mitoxantrone 12 mg/m2 and etoposide 200 mg/m2, randomized with or without the addition of granulocyte-macrophage colony-stimulating factor (GM-CSF) 200 microg/m2. The primary aim was to evaluate the effect of GM-CSF on the remission rate. Secondary aims included comparison of duration of remission, survival and infectious complications and the impact of maintenance therapy with thioguanine. Complete remission (CR) was achieved by 64% of patients without GM-CSF, and by 65% of patients who received GM-CSF, the median remission duration was 13 vs. 6 months, the median overall survival (OS) was 14 vs. 9 months, the mean time to neutrophil recovery was 25 vs. 17 d (P = 0.03) and the number of positive blood cultures was 46 vs. 39 (P = 0.05) respectively. The impact of thioguanine remains unanswered since only 30 patients remained in CR after consolidation therapy. We conclude that induction therapy is feasible with acceptable toxicity in elderly patients with AML, albeit with a high relapse rate and short OS. GM-CSF prior to, and in combination with, induction treatment reduced the time to neutrophil recovery and the number of neutropenic septicaemia cases but did not improve the OS of AML in the elderly.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Leucemia Mieloide/tratamento farmacológico , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Citarabina/administração & dosagem , Etoposídeo/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Neutropenia/induzido quimicamente , Neutropenia/tratamento farmacológico , Infecções Oportunistas/prevenção & controle , Indução de Remissão , Análise de Sobrevida
6.
Leukemia ; 17(9): 1827-33, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12970783

RESUMO

In this prospective randomized multicenter trial 93 patients, median age 72 years, with RAEB-t (n=25) and myelodysplastic syndrome (MDS)-AML (n=68) were allocated to a standard induction chemotherapy regimen (TAD 2+7) with or without addition of granulocyte-macrophage-CSF (GM-CSF). The overall complete remission (CR) rate was 43% with no difference between the arms. Median survival times for all patients, CR patients, and non-CR patients were 280, 550, and 100 days, respectively, with no difference between the arms. Response rates were significantly better in patients with serum lactate dehydrogenase (S-LDH) levels

Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Citarabina/uso terapêutico , Daunorrubicina/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Leucemia Mieloide/tratamento farmacológico , Tioguanina/uso terapêutico , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Refratária com Excesso de Blastos/tratamento farmacológico , Anemia Refratária com Excesso de Blastos/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Transformação Celular Neoplásica , Citarabina/efeitos adversos , Daunorrubicina/efeitos adversos , Feminino , Seguimentos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/administração & dosagem , Humanos , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/patologia , Estudos Prospectivos , Indução de Remissão , Taxa de Sobrevida , Tioguanina/efeitos adversos
7.
Bone Marrow Transplant ; 31(7): 531-7, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12692617

RESUMO

Transformed lymphoma has a reported incidence of 10-70% among patients with follicular lymphoma. Interpreting the wide-ranging estimates for incidence, survival, and effects of interventions from various studies is complicated by the use of different definitions of lymphoma transformation. Problems in defining histologic transformation will be addressed in this review. To date, there are no reliable markers of risk for transformation or factors predictive of survival. The prognosis for transformed lymphoma is generally poor, with most patients surviving only a few months, though some with limited disease that is chemosensitive may experience prolonged survival. Immunotherapy, particularly monoclonal antibodies and radioimmunoconjugates, holds promise but more experience is necessary. Approximately 200 patients are included in published series of autologous transplantation; of these, one-third remain disease free at 5 years, not dissimilar to reported outcomes for nontransformed disease. However, the treatment-related mortality is higher than in nontransformed disease, and there is a significant incidence of post-transplant myelodysplastic syndrome. The role of allogeneic transplant has yet to be pursued, but should be explored for its potential for a graft-versus-lymphoma effect. Advances in microarray gene analysis and biology may facilitate the understanding of mechanisms of transformation, development of a prognostic index and creation of tailored therapy.


Assuntos
Transformação Celular Neoplásica , Transplante de Células-Tronco Hematopoéticas , Linfoma Folicular/patologia , Linfoma Folicular/terapia , Humanos , Incidência , Linfoma Folicular/epidemiologia , Fatores de Risco
8.
Eur J Haematol ; 68(6): 376-81, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12225396

RESUMO

It is still controversial how to treat elderly patients with acute myeloid leukaemia (AML), and results have been poor with most regimens. We report the long-term results of a randomised study performed by the Leukaemia Group of Middle Sweden during 1984-88 comparing two intensive chemotherapeutic drug combinations. Ninety patients >or=60-yr old with untreated AML were randomly allocated to treatment with daunorubicin, cytosine arabinoside (ara-C), and thioguanine (TAD) (43 patients) or a combination in which aclarubicin was substituted for daunorubicin (TAA) (47 patients). Forty-four patients (49%) entered complete remission (CR), 22/43 (51%) in the TAD group and 22/47 (47%) in the TAA group (ns). The CR rate in patients 70 yr 14/48 (29%) (P<0.0001). Early death within 30 d after treatment initiation was more often seen in patients >70 yr than in patients or=10 yr after inclusion of the last patient, 5/90 patients (one in the TAD group and four in the TAA group, respectively) were still alive, four in continuous complete remission and one in second complete remission. Thus, both treatment regimens appear to have similar efficacy, with a relatively high complete remission rate, and a reasonable survival as compared to other studies including some long-term survivors. However, early deaths are still numerous, particularly in patients above 70 yr of age, and the relapse rate is substantial.


Assuntos
Aclarubicina/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Tioguanina/administração & dosagem , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Humanos , Leucemia Mieloide Aguda/classificação , Leucemia Mieloide Aguda/mortalidade , Pessoa de Meia-Idade , Taxa de Sobrevida , Fatores de Tempo
10.
Proc Natl Acad Sci U S A ; 98(24): 13514-8, 2001 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-11707596

RESUMO

We have developed a methodology of prodrug delivery by using a modified insulin species whose biological activity potentially can be regulated in vivo. Native insulin was derivatized with aldol-terminated chemical modifications that can be selectively removed by the catalytic aldolase antibody 38C2 under physiologic conditions. The derivatized organoinsulin (insulin(D)) was defective with respect to receptor binding and stimulation of glucose transport. The affinity of insulin(D) for the insulin receptor was reduced by 90% in binding studies using intact cells. The ability of insulin(D) to stimulate glucose transport was reduced by 96% in 3T3-L1 adipocytes and by 55% in conscious rats. Incubation of insulin(D) with the catalytic aldolase antibody 38C2 cleaved all of the aldol-terminated modifications, restoring native insulin. Treatment of insulin(D) with 38C2 also restored insulin(D)'s receptor binding and glucose transport-stimulating activities in vitro, as well as its ability to lower glucose levels in animals in vivo. We propose that these results are the foundation for an in vivo regulated system of insulin activation using the prohormone insulin(D) and catalytic antibody 38C2 with potential therapeutic application.


Assuntos
Anticorpos Catalíticos/metabolismo , Frutose-Bifosfato Aldolase/metabolismo , Fragmentos Fab das Imunoglobulinas/metabolismo , Insulina/metabolismo , Precursores de Proteínas/metabolismo , Células 3T3 , Actinas/metabolismo , Animais , Catálise , Linhagem Celular , Glucose/metabolismo , Humanos , Insulina/biossíntese , Masculino , Camundongos , Precursores de Proteínas/biossíntese , Ratos , Ratos Wistar , Receptor de Insulina/metabolismo
11.
J Mol Biol ; 314(1): 93-102, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11724535

RESUMO

Murine antibody 1D4 selectively catalyzes a highly disfavored beta-elimination reaction. Crystal structures of unliganded 1D4 and 1D4 in complex with a transition-state analog (TSA) have elucidated a possible general base mode of catalysis. The structures of the unliganded and liganded Fabs were determined to 1.80 and 1.85 A resolution, respectively. The structure of the complex reveals a binding pocket with high shape complementarity to the TSA, which is recruited to coerce the substrate into the sterically demanding, eclipsed conformation that is required for catalysis. A histidine residue and two water molecules are likely involved in the catalysis. The structure supports either a concerted E2 or stepwise E1cB-like mechanism for elimination. Finally, the liganded 1D4 structure shows minor conformational rearrangements in CDR H2, indicative of induced-fit binding of the hapten. 1D4 has pushed the boundaries of antibody-mediated catalysis into the realm of disfavored reactions and, hence, represents an important milestone in the development of this technology.


Assuntos
Anticorpos Catalíticos/química , Anticorpos Catalíticos/metabolismo , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/metabolismo , Animais , Anticorpos Catalíticos/imunologia , Sítios de Ligação de Anticorpos , Catálise , Cátions/metabolismo , Cristalografia por Raios X , Entropia , Haptenos/química , Haptenos/imunologia , Haptenos/metabolismo , Ligação de Hidrogênio , Fragmentos Fab das Imunoglobulinas/imunologia , Imunoglobulina G/química , Imunoglobulina G/imunologia , Imunoglobulina G/metabolismo , Ligantes , Camundongos , Modelos Moleculares , Conformação Proteica , Solventes , Eletricidade Estática , Relação Estrutura-Atividade
12.
J Biol Chem ; 276(52): 49164-8, 2001 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-11606573

RESUMO

The antibody 38C2 efficiently catalyzed a retro-Michael reaction to convert a novel, cell-permeable fluorogenic substrate into fluorescein within living cells. In vitro, the antibody converted the substrate to fluorescein with a k(cat) of 1.7 x 10(-5) s(-1) and a catalytic proficiency (k(cat)/k(uncat)K(m)) of 1.4 x 10(10) m(-1) (K(m) = 7 microm). For hybridoma cells expressing antibody or Chinese Hamster Ovarian (CHO) cells injected with antibody, incubation of the substrate in the extracellular medium resulted in bright intracellular fluorescence distinguishable from autofluorescence or noncatalyzed conversion of substrate. CHO cells loaded with antibody were 12 times brighter than control cells, and more than 85% of injected cells became fluorescent. The fluorescein produced by the antibody traveled into neighboring cells through gap junctions, as demonstrated by blocking dye transfer using the gap junction inhibitor oleamide. The presence of functional gap junctions in CHO cells was confirmed through oleamide inhibition of lucifer yellow transfer. These studies demonstrate the utility of the intracellular antibody reaction, which could generate tracer dyes in specific cells within complex multicellular environments simply by bathing the system in substrate.


Assuntos
Anticorpos Catalíticos/metabolismo , Comunicação Celular/fisiologia , Fluoresceína/metabolismo , Fluoresceínas/metabolismo , Corantes Fluorescentes/metabolismo , Frutose-Bifosfato Aldolase/metabolismo , Junções Comunicantes/metabolismo , Fragmentos Fab das Imunoglobulinas/metabolismo , Animais , Anticorpos Catalíticos/química , Células CHO , Cricetinae , Fluoresceína/química , Fluoresceínas/química , Corantes Fluorescentes/química , Microinjeções , Estrutura Molecular
13.
Bioorg Med Chem Lett ; 11(22): 2983-6, 2001 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-11677141

RESUMO

We developed a visible detection system for antibody-catalyzed retro-aldol-retro-Michael reactions. Aldolase antibody 38C2 catalyzed the reaction of substrate 1 to provide 6-bromo-2-napthol that forms a visible colored azo dye with diazonium salts. This system has potential for the screening of novel catalysts.


Assuntos
Anticorpos Catalíticos/metabolismo , Frutose-Bifosfato Aldolase/imunologia , Animais , Bactérias/efeitos dos fármacos , Biotransformação , Catálise , Compostos de Diazônio , Hibridomas/efeitos dos fármacos , Cinética , Camundongos , Naftóis/química
14.
Science ; 293(5536): 1806-11, 2001 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-11546867

RESUMO

Recently we reported that antibodies can generate hydrogen peroxide (H2O2) from singlet molecular oxygen (1O2*). We now show that this process is catalytic, and we identify the electron source for a quasi-unlimited generation of H2O2. Antibodies produce up to 500 mole equivalents of H2O2 from 1O2*, without a reduction in rate, and we have excluded metals or Cl- as the electron source. On the basis of isotope incorporation experiments and kinetic data, we propose that antibodies use H2O as an electron source, facilitating its addition to 1O2* to form H2O3 as the first intermediate in a reaction cascade that eventually leads to H2O2. X-ray crystallographic studies with xenon point to putative conserved oxygen binding sites within the antibody fold where this chemistry could be initiated. Our findings suggest a protective function of immunoglobulins against 1O2* and raise the question of whether the need to detoxify 1O2* has played a decisive role in the evolution of the immunoglobulin fold.


Assuntos
Anticorpos Catalíticos/metabolismo , Peróxido de Hidrogênio/metabolismo , Oxidantes/metabolismo , Oxigênio/metabolismo , Água/química , Água/metabolismo , Animais , Anticorpos Catalíticos/química , Sítios de Ligação , Catálise , Sequência Conservada , Cristalografia por Raios X , Humanos , Cinética , Modelos Moleculares , Oxidantes/química , Oxirredução , Conformação Proteica , Oxigênio Singlete , Espectrometria de Massas por Ionização por Electrospray , Termodinâmica , Triptofano/metabolismo , Raios Ultravioleta , Xenônio/metabolismo
16.
Proc Natl Acad Sci U S A ; 98(13): 7528-33, 2001 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-11404472

RESUMO

Effective chemotherapy remains a key issue for successful cancer treatment in general and neuroblastoma in particular. Here we report a chemotherapeutic strategy based on catalytic antibody-mediated prodrug activation. To study this approach in an animal model of neuroblastoma, we have synthesized prodrugs of etoposide, a drug widely used to treat this cancer in humans. The prodrug incorporates a trigger portion designed to be released by sequential retro-aldol/retro-Michael reactions catalyzed by aldolase antibody 38C2. This unique prodrug was greater than 10(2)-fold less toxic than etoposide itself in in vitro assays against the NXS2 neuroblastoma cell line. Drug activity was restored after activation by antibody 38C2. Proof of principle for local antibody-catalyzed prodrug activation in vivo was established in a syngeneic model of murine neuroblastoma. Mice with established 100-mm3 s.c. tumors who received one intratumoral injection of antibody 38C2 followed by systemic i.p. injections with the etoposide prodrug showed a 75% reduction in s.c. tumor growth. In contrast, injection of either antibody or prodrug alone had no antitumor effect. Systemic injections of etoposide at the maximum tolerated dose were significantly less effective than the intratumoral antibody 38C2 and systemic etoposide prodrug combination. Significantly, mice treated with the prodrug at 30-fold the maximum tolerated dose of etoposide showed no signs of prodrug toxicity, indicating that the prodrug is not activated by endogenous enzymes. These results suggest that this strategy may provide a new and potentially nonimmunogenic approach for targeted cancer chemotherapy.


Assuntos
Anticorpos Catalíticos/metabolismo , Etoposídeo/farmacocinética , Etoposídeo/toxicidade , Pró-Fármacos/farmacocinética , Pró-Fármacos/toxicidade , Animais , Biotransformação , Catálise , Divisão Celular/efeitos dos fármacos , Frutose-Bifosfato Aldolase/imunologia , Cinética , Camundongos , Estrutura Molecular , Neuroblastoma , Pró-Fármacos/síntese química , Fatores de Tempo , Células Tumorais Cultivadas
17.
Chemistry ; 7(8): 1691-702, 2001 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-11349910

RESUMO

Naturally occurring epothilones have been synthesized starting from enantiomerically pure aldol compounds 9-11, which were obtained by antibody catalysis. Aldolase antibody 38C2 catalyzed the resolution of (+/-)-9 by enantioselective retro-aldol reaction to afford 9 in 90% ee at 50 % conversion. Compounds 10 and 11 were obtained in more than 99% ee at 50% conversion by resolution of their racemic mixtures using newly developed aldolase antibodies 84G3, 85H6 or 93F3. Compounds 9, 10 and 11 were resolved in multigram quantities and then converted to the epothilones by metathesis processes, which were catalyzed by Grubbs' catalysts.


Assuntos
Antibacterianos/síntese química , Anticorpos Catalíticos/metabolismo , Antineoplásicos/síntese química , Epotilonas , Compostos de Epóxi/síntese química , Tiazóis/síntese química , Antibióticos Antineoplásicos/síntese química , Frutose-Bifosfato Aldolase/metabolismo , Haptenos/metabolismo , Macrolídeos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Myxococcales/metabolismo , Estereoisomerismo
18.
Circulation ; 103(14): 1838-43, 2001 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-11294800

RESUMO

BACKGROUND: Heparin-induced thrombocytopenia (HIT) is an immune-mediated syndrome caused by heparin. Complications range from thrombocytopenia to thrombocytopenia with thrombosis. We report a prospective, historical- controlled study evaluating the efficacy and safety of argatroban, a direct thrombin inhibitor, as anticoagulant therapy in patients with HIT or HIT with thrombosis syndrome (HITTS). METHODS AND RESULTS: Patients with HIT (isolated thrombocytopenia, n=160) or HITTS (n=144) received 2 microgram. kg(-1). min(-1) IV argatroban, adjusted to maintain the activated partial thromboplastin time 1.5 to 3.0 times baseline value. Treatment was maintained for 6 days, on average. Clinical outcomes over 37 days were compared with those of 193 historical control subjects with HIT (n=147) or HITTS (n=46). The incidence of the primary efficacy end point, a composite of all-cause death, all-cause amputation, or new thrombosis, was reduced significantly in argatroban-treated patients versus control subjects with HIT (25.6% versus 38.8%, P=0.014). In HITTS, the composite incidence in argatroban-treated patients was 43.8% versus 56.5% in control subjects (P=0.13). Significant between-group differences by time-to-event analysis of the composite end point favored argatroban treatment in HIT (P=0.010) and HITTS (P=0.014). Argatroban therapy, relative to control subjects, also significantly reduced new thrombosis and death caused by thrombosis (P<0.05). Argatroban-treated patients achieved therapeutic activated partial thromboplastin times generally within 4 to 5 hours of starting therapy and, compared with control subjects, had a significantly more rapid rise in platelet counts (P=0.0001). Bleeding events were similar between groups. CONCLUSIONS: Argatroban anticoagulation, compared with historical control subjects, improves clinical outcomes in patients who have heparin-induced thrombocytopenia, without increasing bleeding risk.


Assuntos
Anticoagulantes/uso terapêutico , Heparina/efeitos adversos , Ácidos Pipecólicos/uso terapêutico , Trombocitopenia/tratamento farmacológico , Idoso , Anticoagulantes/efeitos adversos , Arginina/análogos & derivados , Coagulação Sanguínea/efeitos dos fármacos , Testes de Coagulação Sanguínea , Diarreia/induzido quimicamente , Exantema/induzido quimicamente , Feminino , Hemorragia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Dor/induzido quimicamente , Ácidos Pipecólicos/efeitos adversos , Púrpura/induzido quimicamente , Sulfonamidas , Trombocitopenia/induzido quimicamente , Resultado do Tratamento
19.
J Org Chem ; 66(5): 1725-32, 2001 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-11262119

RESUMO

The synthesis of the first examples of stilbene-tethered hydrophobic C-nucleosides is described. Compounds of this type are targeted for use with our recently reported "blue-fluorescent antibodies" with the aim of probing native and nonnatural DNA. The nucleophilic addition of aryl Grignard reagents to either a protected 2'-deoxy-1'-chloro-ribofuranose or a protected 2'-deoxy-ribonolactone was the key synthetic step and afforded C-nucleosides in good yields. Both routes resulted in a final product that was >/=90% of the beta-anomer. Amide- and ether-based linkers for attachment of trans-stilbene to the nucleobase were assessed for utility during synthesis and in binding of the ligands to a blue-fluorescent monoclonal antibody. X-ray structures of each complex were obtained and serve as a guideline for second-generation stilbene-tethered C-nucleosides. The development of these hydrophobic nucleosides will be useful in current native and nonnatural DNA studies and invaluable for investigations regarding novel, nonnatural genomes in the future.


Assuntos
Anticorpos/química , Nucleosídeos/síntese química , Estilbenos/química , Cristalografia por Raios X , Fluorescência , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
20.
Lakartidningen ; 98(45): 4985-90, 2001 Nov 07.
Artigo em Sueco | MEDLINE | ID: mdl-11816901

RESUMO

Angiogenesis appears to be a prominent feature of many hematological disorders, in particular multiple myeloma. The remissions achieved when treating patients with advanced myeloma with the angiostatic drug thalidomide suggested that the disease might be angiogenesis-dependent. However, the mechanisms for the beneficial effect of thalidomide are, at this time, rather unclear, and may involve other effects beside angiostasis. Nonetheless, these and other observations have spurred an interest in angiogenesis that might lead to new concepts and treatment modalities. Here, an update concerning angiogenesis and multiple myeloma is presented.


Assuntos
Mieloma Múltiplo/irrigação sanguínea , Neovascularização Patológica , Inibidores da Angiogênese/uso terapêutico , Citocinas/biossíntese , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/imunologia , Mieloma Múltiplo/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/imunologia , Talidomida/uso terapêutico
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