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1.
FEMS Yeast Res ; 232023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36708173

RESUMO

Wine is composed of multitudinous flavour components and volatile organic compounds that provide this beverage with its attractive properties of taste and aroma. The perceived quality of a wine can be attributed to the absolute and relative concentrations of favourable aroma compounds; hence, increasing the detectable levels of an attractive aroma, such as ß-ionone with its violet and berry notes, can improve the organoleptic qualities of given wine styles. We here describe the generation of a new grape-must fermenting strain of Saccharomyces cerevisiae that is capable of releasing ß-ionone through the heterologous expression of both the enzyme carotenoid cleavage dioxygenase 1 (CCD1) and its substrate, ß-carotene. Haploid laboratory strains of S. cerevisiae were constructed with and without integrated carotenogenic genes and transformed with a plasmid containing the genes of CCD1. These strains were then mated with a sporulated diploid wine industry yeast, VIN13, and four resultant crosses-designated MQ01-MQ04-which were capable of fermenting the must to dryness were compared for their ability to release ß-ionone. Analyses of their fermentation products showed that the MQ01 strain produced a high level of ß-ionone and offers a fermenting hybrid yeast with the potential to enhance the organoleptic qualities of wine.


Assuntos
Saccharomyces cerevisiae , Vinho , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Odorantes , Norisoprenoides/metabolismo , Fermentação
2.
Chemphyschem ; 21(21): 2367, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33462928

RESUMO

The front cover artwork is provided by the group of Ralf Ludwig at the University of Rostock. The image shows the calculated cyclic octamer of hydroxyl-functionalized cations, being prominent constituents of ionic liquids. Strong cooperative hydrogen bonds overcome like-charge repulsion and prevent the cluster from Coulomb explosion. Read the full text of the Article at 10.1002/cphc.202000681.

3.
Theriogenology ; 108: 185-191, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29223656

RESUMO

Administration of progesterone (P4) after estradiol is usually performed to prepare non-cyclic mares as embryo recipients. However, there are successful pregnancy reports after embryo transfer in non-cyclic mares treated only with progestins. The objective of this study was to evaluate endometrial gene expression and immunostaining for estrogen receptor alpha (ERα), beta (ERß) and progesterone receptor (PR) in seasonal anestrous mares treated with long acting P4 (LA P4). Endometrial tissue from eight seasonal anestrous mares was collected immediately before administration of 1.5 g of LA P4 and five days after. The receptors protein expression was evaluated by immunohistochemistry and the percentage of the immunostained area was determined by ImageJ software. Transcripts abundance for ERα, ERß and PR were determined by RT-qPCR. Blood samples were collected daily to measure plasma P4 concentrations. Protein expression for ERα was greater (p < 0.05) after LA P4 administration, although gene expression was not affected by treatment (p > 0.05). There was no difference for ERß protein expression (p = 0.07) and ERß gene expression was reduced (p < 0.05) after treatment. Gene and protein expression for PR was not altered (p > 0.05). In conclusion, endometrial PR and ERα expression patterns after LA P4 administration were similar to those previously found in protocols using estradiol prior to LA P4 to prepare non-cyclic mares as embryo recipients.


Assuntos
Endométrio/metabolismo , Cavalos/metabolismo , Progesterona/uso terapêutico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Animais , Transferência Embrionária/métodos , Transferência Embrionária/veterinária , Feminino , Perfilação da Expressão Gênica , Imuno-Histoquímica , Progesterona/administração & dosagem , RNA Mensageiro/metabolismo
4.
Theriogenology ; 97: 159-169, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28583600

RESUMO

To test the hypothesis that the administration of 2.5 mg of estradiol benzoate (EB) followed by 1500 mg of long acting progesterone (LA P4) causes similar uterine changes and molecular dynamics in anovulatory mares to those observed in cyclic ones, we evaluated the changes of estrogen (ERα and ERß) and progesterone receptors (PR) in anestrous, transitional and cyclic mares by RT-qPCR and immunohistochemistry. In addition, we evaluated uterine edema, tonus and estrogens and progesterone plasma profile. Endometrial biopsies were taken from anestrous and transitional mares immediately before EB injection, 48 h after EB administration and five days after LA P4 was given. In cyclic mares, biopsies were collected at estrus and at five days after ovulation. Similar estrogen peaks were achieved after the injection of the single EB dose between treated and cyclic groups, as well as maximum uterine edema. Uterine tone was increased to diestrus levels after administration of 1500 mg of LA P4. Changes in relative abundance of transcripts for PR, ERα and ERß when progesterone stimulated endometrium was compared to estrogen stimulated endometrium were similar between cyclic and non-cyclic treated mares. However, apparent decreased PR in the endometrial glandular epithelium was not observed in non-cyclic mares five days after LA P4 administration as observed at five days after ovulation in cyclic mares. The protocol produced similar endometrial edema, uterine tonus and changes in relative abundance of PR, ERα and ERß transcripts to those observed in cyclic mares during late estrus and early diestrus, as well as similar estradiol and estrogen conjugate plasma concentrations.


Assuntos
Estradiol/farmacologia , Ciclo Estral/fisiologia , Cavalos/fisiologia , Progesterona/farmacologia , Útero/efeitos dos fármacos , Animais , Estradiol/administração & dosagem , Feminino , Progesterona/administração & dosagem , Útero/fisiologia
5.
Theriogenology ; 86(7): 1749-56, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27494983

RESUMO

The present study evaluated the influence of different regimens of estradiol benzoate (EB) treatments followed by a single dose of long-acting progesterone (LA P4) on plasma estrogen and P4 concentrations in noncyclic mares prepared as embryo recipients. Twenty-one anestrous mares were distributed into three groups (n = 7 mares per group), according to the EB dose received (single dose of 2.5 mg, total of 5 mg in decreasing doses, and total of 10 mg in decreasing doses), which was followed by a single administration of 1500 mg of LA P4 in all groups. Mares were reevaluated during the ovulatory phase and seven of them became part of the cyclic nontreated control group. Ultrasonography was performed to monitor endometrial edema, and blood samples were collected to measure estradiol (E2), estrogen conjugate (EC), and P4 by RIA. Maximum uterine edema was achieved 24 hours after administration of EB in all treated groups. Maximum E2 concentrations were observed 24 hours after the first EB injection in treated groups and there were no differences (P > 0.05) among treatments. Maximum EC concentration was observed 24 hours after the single EB injection in the 2.5-mg group, whereas in the 5- and 10-mg groups EC peaks were observed 48 hours after the first EB administration. Maximum P4 concentrations were detected 24 hours after LA P4 injection, although higher P4 concentrations were observed in the group treated with 2.5 mg of EB than in that treated with 10 mg of EB (P < 0.05). Because P4 concentrations were reduced after administration of high doses of EB, we also measured 17α-hydroxyprogesterone (17-OH-P) to test the hypothesis that high concentrations of EB would accelerate the conversion of P4 to 17-OH-P. However, 17-OH-P concentrations paralleled P4 profile in all groups, irrespective of EB doses. In summary, the three EB treatment regimens induced similar E2 peaks, although the observation of EC peaks 24 hours after E2 peaks in the 5- and 10-mg groups indicate that an excess of E2 was given, which was converted into EC to be inactivated. Administration of 10 mg of EB reduced P4 concentrations 24 hours after LA P4 was given. We demonstrated that the mechanism by which this reduction occurred was not by an increase in P4 metabolism to 17α-OH-P. In conclusion, the use of 2.5 mg of EB followed by 1500 mg of LA P4 appears to be a more appropriate regimen to treat noncyclic mares, although additional studies are needed to verify embryo survival with this treatment dose.


Assuntos
Transferência Embrionária/veterinária , Estradiol/análogos & derivados , Cavalos/fisiologia , Prenhez , Progesterona/farmacologia , Animais , Preparações de Ação Retardada , Esquema de Medicação , Estradiol/administração & dosagem , Estradiol/farmacologia , Feminino , Gravidez , Prenhez/efeitos dos fármacos , Progesterona/administração & dosagem
6.
Bone Marrow Transplant ; 50(5): 679-84, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25642765

RESUMO

Prognosis is poor for patients with biologically aggressive Non-Hodgkin lymphoma (NHL), refractory to chemotherapy or relapsed after autologous transplantation, especially when no disease control before allogeneic transplantation is achieved. In 16 patients (median age 53, median prior regimes 5) with relapsed or refractory non-remission NHL, we analysed retrospectively the efficacy of a sequential therapy comprising clofarabine re-induction followed by a reduced-intensity conditioning with fludarabine, CY and melphalan, and T-cell-replete HLA-haploidentical transplantation. High-dose CY was utilized post-transplantation. All patients engrafted. Early response (day +30) was achieved in 94%. Treatment-related grade III-IV toxicity occurred in 56%, most commonly transient elevation of transaminases (36%), while there was a low incidence of infections (19% CMV reactivation, 19% invasive fungal infection) and GVHD (GVHD: acute III-IV: 6%; mild chronic: 25%). One-year non-relapse mortality was 19%. After a median follow-up of 21 months, estimated 1- and 2-year PFS was 56 and 50%, respectively, with 11 patients (69%) still alive after 2 years. In summary, sequential therapy is feasible and effective and provides an acceptable toxicity profile in high-risk non-remission NHL. Presumably, cytotoxic reinduction with clofarabine provides enough remission time for the graft-versus lymphoma effect of HLA-haploidentical transplantation to kick in, even in lymphomas that are otherwise chemo-refractory.


Assuntos
Nucleotídeos de Adenina/administração & dosagem , Antimetabólitos Antineoplásicos/administração & dosagem , Arabinonucleosídeos/administração & dosagem , Antígenos HLA , Transplante de Células-Tronco Hematopoéticas , Linfoma não Hodgkin , Adulto , Idoso , Aloenxertos , Clofarabina , Intervalo Livre de Doença , Feminino , Humanos , Linfoma não Hodgkin/mortalidade , Linfoma não Hodgkin/terapia , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Taxa de Sobrevida
7.
Bone Marrow Transplant ; 49(7): 895-901, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24820212

RESUMO

Haploidentical haematopoietic SCT (HSCT) using T-cell-replete grafts and post-transplant high-dose CY has found increasing acceptance. Our purpose was to evaluate the feasibility and outcome of this strategy as second HSCT incorporating donor change for acute leukaemia relapse after a first allogeneic transplantation. The courses of 20 consecutive adults (median age 37 years, 12 male) with AML (n=14), ALL (n=5) and acute bi-phenotypic leukaemia (n=1) were analysed retrospectively. Conditioning consisted of fludarabine, CY and either melphalan or TBI or tresosulfan+/-etoposide. Engraftment was achieved in 17 (85%), and a second remission was induced in 15 patients (75%) on day +30. The rate of grade II-IV acute GvHD was 35%, while chronic GvHD occurred in five patients. Most commonly observed grade III-IV toxicities were mucositis (30%), hyperbilirubinemia (20%), elevation of transaminases (20%) and creatinine (20%), while invasive fungal infection affected 30%. One-year non-relapse mortality (NRM) was 36%. At a median follow-up of 17 months, estimated 1-year OS was 45%, and 1-year relapse-free survival was 33%. This strategy was feasible and allowed for successful engraftment with a moderate rate of toxicity. Early outcome and NRM are at least comparable with results after a second HSCT from HLA-matched donors without donor change at HSCT2.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia/terapia , Condicionamento Pré-Transplante/métodos , Doença Aguda , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Doadores de Tecidos , Transplante Homólogo , Adulto Jovem
8.
Haemophilia ; 20(5): 651-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24697870

RESUMO

Haemostatic management of haemophilia B patients undergoing surgery is critical to patient safety. The aim of this ongoing prospective trial was to investigate the haemostatic efficacy and safety of a recombinant factor IX (rFIX) (Bax326) in previously treated subjects (12-65 years, without history of FIX inhibitors) with severe or moderately severe haemophilia B, undergoing surgical, dental or other invasive procedures. Haemostatic efficacy was assessed according to a predefined scale. Blood loss was compared to the average and maximum blood loss predicted preoperatively. Haemostatic FIX levels were achieved peri- and postoperatively in 100% of subjects (n = 14). Haemostasis was 'excellent' intraoperatively in all patients and postoperatively in those without a drain, and 'excellent' or 'good' at the time of drain removal and day of discharge in those with a drain employed. Following the initial dose, the mean FIX activity level rose from 6.55% to 107.58% for major surgeries and from 3.60% to 81.4% for minor surgeries. Actual vs. predicted blood loss matched predicted intraoperative blood loss but was equal to or higher than (but less than 150%) the maximum predicted postoperative blood loss reflecting the severity of procedure and FIX requirements. There were no related adverse events, severe allergic reactions or thrombotic events. There was no evidence that BAX326 increased the risk of inhibitor or binding antibody development to FIX. BAX326 was safe and effective for peri-operative management of 14 subjects with severe and moderately severe haemophilia B.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Coagulantes/uso terapêutico , Fator IX/uso terapêutico , Hemofilia B/tratamento farmacológico , Hemostasia Cirúrgica/métodos , Procedimentos Cirúrgicos Operatórios/métodos , Adolescente , Adulto , Idoso , Inibidores dos Fatores de Coagulação Sanguínea/imunologia , Estudos de Casos e Controles , Criança , Coagulantes/efeitos adversos , Fator IX/efeitos adversos , Feminino , Hemofilia B/imunologia , Hemorragia/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória , Cuidados Pós-Operatórios , Estudos Prospectivos , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Adulto Jovem
9.
Haemophilia ; 20(1): 15-24, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23834666

RESUMO

BAX326 is a recombinant factor IX (rFIX; nonacog gamma) manufactured without the addition of any materials of human or animal origin, and with two viral inactivation steps (solvent/detergent treatment and 15 nm nanofiltration). The aim of this prospective trial was to investigate the pharmacokinetics, haemostatic efficacy and safety of BAX326 in previously treated patients aged 12-65 years with severe or moderately severe haemophilia B. BAX326 was safe and well tolerated in all 73 treated subjects; adverse events considered related to treatment (2.7% incidence, all non-serious) were transient and mild, and no hypersensitivity reactions, inhibitor formation or thrombotic events were observed. Pharmacokinetic (PK) equivalence (n = 28) between BAX326 and a licensed rFIX was confirmed in terms of the ratio of geometric mean AUC(0-72) h per dose. Twice-weekly prophylaxis [mean duration 6.2 (±0.7) months; 1.8 (±0.1) infusions per week, 49.5 (±4.8) IU kg(-1) per infusion] was effective in preventing bleeding episodes, with a significantly lower (79%, P < 0.001) annualized bleed rate (4.2) compared to an on-demand treatment in a historical control group (20.0); 24 of 56 subjects on prophylaxis (43%) did not bleed throughout the study observation period. Of 249 total acute bleeds, 211 (84.7%) were controlled with one to two infusions of BAX326. Haemostatic efficacy at resolution of bleed was rated excellent or good in 96.0% of all treated bleeding episodes. The results of this study indicate that BAX326 is safe and efficacious in treating bleeds and routine prophylaxis in patients aged 12 years and older with haemophilia B.


Assuntos
Fator IX/uso terapêutico , Hemofilia B/tratamento farmacológico , Proteínas Recombinantes , Adolescente , Adulto , Idoso , Coagulação Sanguínea/efeitos dos fármacos , Criança , Fator IX/farmacocinética , Feminino , Hemofilia B/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Pré-Medicação , Qualidade de Vida , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
10.
Phys Rev Lett ; 108(17): 170602, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22680848

RESUMO

For simulation studies of (macro) molecular liquids it would be of significant interest to be able to adjust or increase the level of resolution within one region of space, while allowing for the free exchange of molecules between open regions of different resolution or representation. We generalize the adaptive resolution idea and suggest an interpretation in terms of an effective generalized grand canonical approach. The method is applied to liquid water at ambient conditions.

11.
Genes Brain Behav ; 11(1): 69-78, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21906262

RESUMO

Receptor-interacting protein 140 (RIP140) is a negative transcriptional coregulator of nuclear receptors such as estrogen, retinoic acid or glucocorticoid receptors. Recruitment of RIP140 results in an inhibition of target gene expression through different repressive domains interacting with histone deacetylases or C-terminal binding proteins. In this study, we analyzed the role of RIP140 activity in memory processes using RIP140-deficient transgenic mice. Although the RIP140 protein was clearly expressed in the brain (cortical and hippocampus areas), the morphological examination of RIP140(-/-) mouse brain failed to show grossly observable alterations. Using male 2-month-old RIP140(-/-) , RIP140(+/-) or RIP140(+/+) mice, we did not observe any significant differences in the open-field test, rotarod test and in terms of spontaneous alternation in the Y-maze. By contrast, RIP140(-/-) mice showed long-term memory deficits, with an absence of decrease in escape latencies when animals were tested using a fixed platform position procedure in the water maze and in the passive avoidance test. Noteworthy, RIP140(-/-) mice showed decreased swimming speed, suggesting swimming alterations that may in part account for the marked alterations measured in the water maze. Moreover, RIP140(+/-) and RIP140(-/-) mice showed a significant increase in immobility time in the forced swimming test as compared with wild-type animals. These observations showed that RIP140 gene depletion results in learning and memory deficits as well as stress response, bringing to light a major role for this transcriptional coregulator in the neurophysiological developmental mechanisms underlying cognitive functions.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Reação de Fuga/fisiologia , Inativação Gênica , Resposta de Imobilidade Tônica/fisiologia , Memória de Longo Prazo/fisiologia , Proteínas Nucleares/genética , Adaptação Fisiológica , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Encéfalo/metabolismo , Cognição/fisiologia , Comportamento Exploratório/fisiologia , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/fisiologia , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Transgênicos , Proteínas Nucleares/metabolismo , Proteína 1 de Interação com Receptor Nuclear , Teste de Desempenho do Rota-Rod , Estresse Psicológico/fisiopatologia , Natação , Distribuição Tecidual
12.
Haemophilia ; 17(3): 433-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21299740

RESUMO

Replacement therapy or prophylaxis, has become the standard of care for the treatment of severe haemophilia A. To describe bleeding patterns in children, adolescents and adults on prophylaxis and their observed relationships to times of infusion (during the week and during the day) as well as season of the year. Data from Advate pre-licensure prospective clinical trials from 145 patients with factor VIII (FVIII) <1%, were used. All patients underwent a 48-h pharmacokinetic study. The 10-65 year group had ≥ 75 exposure days on fixed prophylaxis (25-40 IU kg(-1) 3-4x per week). Prophylaxis was not fixed but similar for 1-6 year olds. Bleeding patterns were analysed. Overall, 700 bleeds were observed in 110/145 patients. All were treated with prophylaxis, mean dose 108 IU kg(-1) week(-1) in on average 2.9 infusions (1-6 years), 86 IU kg (-1) week(-1) in 2.7 infusions (10-17 years), and 75 IU kg (-1) week(-1) in 2.6 infusions (18-65 years), respectively. On prophylaxis, median total bleeds per year were low at 3.1 for patients aged 1-6 years, 3.3 for those aged 10-17 years and 2.1 for patients aged 18-65 years. Patients aged 1-6 years had predominantly soft tissue bleeds (79%). Incidence of joint bleeding was not associated with season, but was significantly lower in patients who infused FVIII in the mornings: median 0 per year (IQR 0.0-0.4) compared to those who infused later [median 1.8 per year (IQR 0.0-5.2)]. Older patients predominantly experienced joint bleeds (50% and 62%, respectively). More joint bleeds occurred during the summer [43 and 46% respectively, (P < 0.01)]. Bleeding patterns in patients on prophylaxis varied according to age. In addition, the 10-65 year olds showed increased bleeding during the summer. After confirmation in prospective studies, this information may be used to improve tailoring of prophylactic treatment.


Assuntos
Fator VIII/uso terapêutico , Hemofilia A/tratamento farmacológico , Hemorragia/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Fator VIII/administração & dosagem , Fator VIII/farmacocinética , Hemartrose/epidemiologia , Hemartrose/etiologia , Hemorragia/etiologia , Humanos , Lactente , Pessoa de Meia-Idade , Estudos Prospectivos , Estações do Ano , Fatores de Tempo , Adulto Jovem
13.
J Thromb Haemost ; 8(4): 730-6, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20398185

RESUMO

BACKGROUND: Dose tailoring of coagulation factors requires reliably estimated and reproducible pharmacokinetics (PK) in the individual patient. OBJECTIVES: To investigate the contribution of both biological and methodological factors to the observed variability of factor VIII (FVIII) PK, with the focus on differences between children and adults, and to examine the implications for dosing. PATIENTS: Data from 52 1-6-year-old and 100 10-65-year-old patients with hemophilia A (FVIII < or = 2 IU dL(-1)) in three clinical studies were included. RESULTS: In vivo recovery was lower, weight-adjusted clearance was higher and FVIII half-life was on average shorter in children than in adults. However, a reduced blood sampling schedule for children was estimated to account for up to one half of the total observed differences. Intrapatient variance in PK was smaller than interpatient variance in 10-65-year-olds. Age and ratio of actual to ideal weight only showed weak relationships with PK parameters. Variance in PK caused large variance in the calculated dose required to maintain a target FVIII trough level during prophylactic treatment. CONCLUSION: Differences in blood sampling schedules should be taken into account when results from different PK studies are compared. However, even with this consideration, PK cannot be predicted from observable patient characteristics but must be determined for the individual. Because the influence of reducing the blood sampling was minor in comparison to the true variance between patients, a reduced blood sampling protocol can be used. Low intrapatient variability supports the use of PK measurements for dose tailoring of FVIII.


Assuntos
Coagulantes/administração & dosagem , Coagulantes/farmacocinética , Cálculos da Dosagem de Medicamento , Monitoramento de Medicamentos , Fator VIII/administração & dosagem , Fator VIII/farmacocinética , Hemofilia A/tratamento farmacológico , Adolescente , Adulto , Fatores Etários , Idoso , Estatura , Índice de Massa Corporal , Peso Corporal , Criança , Pré-Escolar , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Coagulantes/sangue , Relação Dose-Resposta a Droga , Meia-Vida , Hemofilia A/sangue , Humanos , Lactente , Modelos Lineares , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Adulto Jovem
14.
J Thromb Haemost ; 8(2): 269-75, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19943875

RESUMO

BACKGROUND: Prophylactic factor (F)VIII has been shown to reduce bleeds and arthropathy in patients with severe hemophilia A. OBJECTIVES: Assuming that the trough FVIII level is an important determinant of the efficacy of prophylaxis, this paper addresses the effect of the inter-patient variability in pharmacokinetics and different dosing regimens on trough levels. METHODS: Simulations used FVIII half-lives and in vivo recoveries (IVR), observed during clinical trials with Advate [Antihemophilic Factor (Recombinant), Plasma/Albumin-Free Method], and commonly used prophylactic regimens to calculate their effect on FVIII levels during prophylaxis. RESULTS AND CONCLUSIONS: Half-life and dose frequency had a larger effect on trough FVIII and time per week with FVIII<1 IU dL(-1) than IVR and infused dose per kg. The combined effect of these parameters resulted in substantial inter-patient variability in the amount of FVIII required to sustain a desired trough level. Prophylactic regimens based on Monday, Wednesday, Friday dosing were less cost effective in maintaining a desired trough level throughout the week. Dose escalation on Friday to cover the weekend would require potentially harmful doses of FVIII in many patients, especially in young children where more than 50% would require a Friday dose of over 100 IU kg(-1) and some would require more than 400 IU kg(-1). Knowledge of individual patients' half-lives and alteration of frequency of infusions may allow the more cost-effective use of FVIII and potentially expand access to prophylaxis to a greater number of patients, especially in regions where healthcare resources are scarce.


Assuntos
Coagulantes/administração & dosagem , Coagulantes/farmacocinética , Fator VIII/administração & dosagem , Fator VIII/farmacocinética , Hemartrose/prevenção & controle , Hemofilia A/tratamento farmacológico , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Coagulantes/sangue , Coagulantes/economia , Simulação por Computador , Análise Custo-Benefício , Esquema de Medicação , Custos de Medicamentos , Cálculos da Dosagem de Medicamento , Monitoramento de Medicamentos , Fator VIII/economia , Meia-Vida , Hemartrose/sangue , Hemartrose/economia , Hemartrose/etiologia , Hemofilia A/sangue , Hemofilia A/complicações , Hemofilia A/economia , Humanos , Lactente , Infusões Parenterais , Pessoa de Meia-Idade , Modelos Biológicos , Estudos Prospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
17.
J Thromb Haemost ; 7(3): 413-20, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19143924

RESUMO

BACKGROUND: The role of prophylactic factor VIII (FVIII) to decrease hemophilic bleeding and arthropathy is well established. The rationale for this strategy is to convert patients with severe hemophilia A to a moderate clinical phenotype by reducing time spent with a FVIII level <1 IU dL(-1). Studies to date, however, have not demonstrated a strong link between FVIII level and the bleeding rate. OBJECTIVES: To assess the effect of FVIII level on break-through bleeding in patients with severe hemophilia A on prophylaxis. PATIENTS/METHODS: This study analysed data from 44 patients aged 1-6 and 99 patients aged 10-65 years with severe hemophilia A (FVIII <1 IU dL(-1)) who were treated with prophylactic FVIII as part of clinical studies assessing pharmacokinetics, safety and efficacy of a recombinant FVIII (Advate). Each patient had pharmacokinetic measurements and FVIII infusions recorded, and these were used to calculate time spent with a FVIII below 1, 2 and 5 IU dL(-1). RESULTS: The data demonstrate that increasing time with a FVIII below 1 IU dL(-1) is associated with increased total bleeds and hemarthroses. Lack of adherence to the intended frequency of FVIII infusion was the most important determinant of low FVIII and increased bleeding. In children aged 1-6 years, the rate of bleeding was also influenced by FVIII half-life and clearance. CONCLUSIONS: These data have important implications for the management of patients with severe hemophilia.


Assuntos
Fator VIII/administração & dosagem , Hemofilia A/complicações , Hemorragia/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Fator VIII/análise , Fator VIII/farmacocinética , Hemofilia A/tratamento farmacológico , Humanos , Lactente , Pessoa de Meia-Idade , Farmacocinética , Pré-Medicação , Adulto Jovem
20.
Vaccine ; 24(24): 5256-63, 2006 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-16624457

RESUMO

A prospective, randomised, multicentre, single-blind phase 3 study was performed to assess the safety of a vaccination schedule consisting of two vaccinations (21-35 days apart) with the tick-borne encephalitis (TBE) vaccine FSME-IMMUN "adults" (five consecutive lots) in comparison to another licensed TBE vaccine (Encepur), with polygeline) (two lots) in healthy volunteers (n=3966) aged 16-65 years. The safety of the third vaccination with FSME-IMMUN "adults" (6 months after the first vaccination) was investigated in a follow-up study on the same population (n=3705) and TBE antibody titres were analysed pre- and post-vaccination in a subgroup of volunteers (n=564). Following the first vaccination, the overall incidence of fever (> or =38.0 degrees C) was 0.8% in the FSME-IMMUN "adults" study group and 5.6% in the comparator study group; fever was mainly mild. The fever rate after the second vaccination was 0.6% and 0.5% in the two study groups, respectively. Local and systemic reactions after the first vaccination occurred with a lower frequency in the FSME-IMMUN "adults" study group than in the comparator group. Upon analysing the tolerability of the third vaccination with FSME-IMMUN "adults", similar results were determined in both study groups of volunteers previously vaccinated with FSME-IMMUN "adults" or with the comparator vaccine. The immunogenicity results demonstrated similar seroconversion rates (as determined by ELISA or neutralization test) before and after the third vaccination in the FSME-IMMUN "adults" group and in the comparator group respectively. The results of both studies demonstrate that: (1) FSME-IMMUN "adults" is safe and highly immunogenic, (2) all five production lots of FSME-IMMUN "adults" were consistent with respect to a low rate of adverse events, (3) FSME-IMMUN "adults" induces considerably lower adverse reaction rates than the comparator vaccine after the first vaccination, and (4) two vaccinations with the comparator vaccine can be successfully followed by a third vaccination with FSME-IMMUN "adults".


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/imunologia , Vacinas Virais/efeitos adversos , Vacinas Virais/imunologia , Adolescente , Adulto , Idoso , Anticorpos Antivirais/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Vacinação
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