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1.
Platelets ; 33(8): 1185-1191, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-35549802

RESUMO

The thrombopoietin mimetic peptide for injection is a second-generation thrombopoietin receptor agonist (TPO-RA) used in the treatment of patients with immune thrombocytopenia. The aim of the present study was to assess the safety, tolerance, pharmacokinetic and pharmacodynamic properties of thrombopoietin mimetic peptide for injection in Chinese healthy volunteers. A randomized, placebo-controlled, double-blind, dose-escalation study was conducted in healthy Chinese subjects aged 18-50 years. Thirty subjects received single subcutaneous injection of 0.3 µg/kg, 1.0 µg/kg, 2.0 µg/kg thrombopoietin mimetic peptide or placebo. Thrombopoietin mimetic peptide was safe and well tolerated at doses of 0.3-2.0 µg/kg. There was no significant change in mean platelet count (PLT) from baseline at the 0.3 µg/kg or placebo groups. The mean PLT of subjects in the 1.0 µg/kg and 2.0 µg/kg groups peaked at day 12 (± 1), began to decline around day 17, and returned to the baseline level at day 28 (± 1). Platelet aggregation rates of the three dose groups showed no significant change before and after administration. Serum concentrations of thrombopoietin mimetic peptide in all subjects were below the quantization limit. This was the first study to demonstrate that subcutaneous injection of thrombopoietin mimetic peptide at doses of 0.3-2.0 µg/kg was safe and well tolerated in Chinese healthy subjects. As a second-generation TPO-RA, thrombopoietin mimetic peptide is effective at improving PLT after single subcutaneous injection at dose of ≥1 µg/kg.P lain l anguage s ummaryWhat is the context?● Immune thrombocytopenia (ITP) is a rare, serious autoimmune disorder characterized by low platelet count (PLT) without an alternate cause. The treatment goal of ITP is to increase the platelet count to a safe level that can stop active bleeding and reduce the risks of future bleeding.● Thrombopoietin receptor agonists (TPO-RAs, e.g. eltrombopag, avatrombopag, hetrombopag, and romiplostim) have shown high response rates in stimulating platelet production and reducing the risk of bleeding. TPO-RAs provide ITP patients with well-tolerated, long-term treatment choices.What is new?● The thrombopoietin mimetic peptide for injection is a new TPO-RAs developed by Shandong Quangang Pharmaceutical Co., Ltd. (China).● This study showed that thrombopoietin mimetic peptide is effective at improving PLT after a single subcutaneous injection.● The thrombopoietin mimetic peptide is safe and well-tolerated in Chinese healthy subjects.What is the impact?● This study provides evidence for the further development potential of the thrombopoietin mimetic peptide.


Assuntos
Púrpura Trombocitopênica Idiopática , Trombocitopenia , Método Duplo-Cego , Humanos , Peptídeos , Preparações Farmacêuticas , Púrpura Trombocitopênica Idiopática/complicações , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Receptores Fc/uso terapêutico , Receptores de Trombopoetina/agonistas , Proteínas Recombinantes de Fusão/efeitos adversos , Trombocitopenia/etiologia , Trombopoetina/efeitos adversos
2.
J Clin Pharm Ther ; 47(8): 1112-1121, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35396752

RESUMO

WHAT IS KNOWN AND OBJECTIVE: For patients after percutaneous coronary interventions (PCI), clopidogrel combined with aspirin is a conventional dual antiplatelet therapy (DAPT) method. Because the genetic polymorphism of CYP2C19 gene leads to clopidogrel resistance, guidelines for antiplatelet recommendations in CYP2C19 of ultrarapid metabolizers (UM), extended metabolizers (EM) and poor metabolizers (PM) are clear. However, there is no clear recommendation as to whether ticagrelor or double dose clopidogrel is the best antiplatelet regimen for CYP2C19 of intermediate metabolizers (IM). To evaluate the efficacy and safety of ticagrelor (combined with aspirin) and high-dose clopidogrel (combined with aspirin) in patients after PCI with CYP2C19 loss-of-function (LOF) alleles. METHODS: We searched the following databases to select RCTs of comparing ticagrelor with high-dose clopidogrel in patients after PCI with CYP2C19 LOF alleles: CNKI, Wanfang Data, PubMed, Clinical trials, Cochrane, Web of Science and Embase. Major adverse cardiovascular events (MACEs), platelet function and TIMI bleeding event were defined as the outcomes. revman 5.3 software was used to perform meta-analysis. RESULTS AND DISCUSSION: A total of 14 RCTs with 2351 patients were enrolled. Meta-analysis showed that compared with high-dose clopidogrel, ticagrelor had reduced incidence of MACEs (OR = 0.32, 95% Cl: 0.23-0.44, p < 0.00001), stent thrombosis (OR: 0.24, 95%CI: 0.13-0.44, p < 0.00001), myocardial infarction OR: 0.42, 95%CI: 0.22-0.80, p = 0.008), revascularization (OR: 0.29, 95%CI: 0.10-0.82, p = 0.02) and unstable angina (OR: 0.47, 95%CI: 0.29-0.77, p = 0.003) in patients after PCI with CYP2C19 LOF alleles. A subgroup analysis showed that ticagrelor reduced the risk of MACEs compared with high-dose clopidogrel regardless of the type of metabolizer. Compared with high-dose clopidogrel, ticagrelor significantly reduced the risk of MACE with longer follow-up period (more than 3 months) without increasing the risk of bleeding (OR: 0.89, 95%CI: 0.53-1.49, p = 0.30), while elevated dyspnoea (OR: 5.62, 95%CI: 3.07-10.28, p < 0.00001). WHAT IS NEW AND CONCLUSIONS: For patients carrying CYP2C19 LOF alleles after PCI, ticagrelor may be better than high-dose clopidogrel in reducing the risk of MACEs, while dyspnoea incidents should be alerted.


Assuntos
Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , Síndrome Coronariana Aguda/tratamento farmacológico , Aspirina , Clopidogrel , Citocromo P-450 CYP2C19/genética , Dispneia/induzido quimicamente , Dispneia/tratamento farmacológico , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Humanos , Inibidores da Agregação Plaquetária , Ensaios Clínicos Controlados Aleatórios como Assunto , Ticagrelor , Resultado do Tratamento
3.
PLoS Genet ; 15(9): e1008368, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31518356

RESUMO

Telomere shortening is associated with aging and age-associated diseases. Additionally, telomere dysfunction resulting from telomerase gene mutation can lead to premature aging, such as apparent skin atrophy and hair loss. However, the molecular signaling linking telomere dysfunction to skin atrophy remains elusive. Here we show that dysfunctional telomere disrupts BMP/pSmad/P63 signaling, impairing epidermal stem cell specification and differentiation of skin and hair follicles. We find that telomere shortening mediated by Terc loss up-regulates Follistatin (Fst), inhibiting pSmad signaling and down-regulating P63 and epidermal keratins in an ESC differentiation model as well as in adult development of telomere-shortened mice. Mechanistically, short telomeres disrupt PRC2/H3K27me3-mediated repression of Fst. Our findings reveal that skin atrophy due to telomere dysfunction is caused by a previously unappreciated link with Fst and BMP signaling that could be explored in the development of therapies.


Assuntos
Células-Tronco/metabolismo , Encurtamento do Telômero/fisiologia , Animais , Atrofia/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular/genética , Linhagem da Célula/genética , Proliferação de Células/genética , Células Epidérmicas/metabolismo , Epiderme/metabolismo , Regulação da Expressão Gênica/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Transdução de Sinais/genética , Proteínas Smad/metabolismo , Telômero/genética , Encurtamento do Telômero/genética , Transativadores/metabolismo
4.
Eur J Clin Pharmacol ; 76(3): 383-391, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31873765

RESUMO

PURPOSE: The aim of the present study was to evaluate the safety, pharmacokinetic (PK) and pharmacodynamic (PD) properties of remimazolam besylate following single ascending dose (SAD) and continuous infusion in healthy Chinese volunteers. METHODS: This was a randomized phase I study conducted in two parts. Part I was a double-blind, placebo- and midazolam-controlled, SAD study among healthy Chinese participants with a remimazolam dose of 0.025-0.4 mg/kg. Part II was an open-label, midazolam-controlled, continuous infusion study. Bispectral index (BIS) monitoring and Modified Observers Assessment of Alertness and Sedation (MOAA/S) score assessment were used to assess the PD properties. RESULTS: The half-life range of remimazolam was from 34.1 ± 8.1 to 59.8 ± 20.5 min in the SAD study. The sedation function was initially observed at the dose of 0.05 mg/kg remimazolam. Doses of ≥ 0.075 mg/kg exerted a peak sedation effect within 1-2 min after injection, resulting in a deeper and more rapid sedation. In the 2 h continuous infusion, remimazolam showed a deeper sedation and more rapid recovery than midazolam. For general anesthesia, an induction dosage of 0.2 mg/kg/min and a maintenance dosage of 1 mg/kg/h can achieve a satisfactory efficacy effect. CONCLUSIONS: Remimazolam was safe and well tolerated in healthy Chinese participants. Based on the phase I clinical study, we suggest that remimazolam besylate demonstrates greater sedation and quicker recovery from sedation than midazolam.


Assuntos
Benzodiazepinas/efeitos adversos , Benzodiazepinas/farmacocinética , Relação Dose-Resposta a Droga , Adulto , Povo Asiático , Benzodiazepinas/uso terapêutico , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Hipnóticos e Sedativos/efeitos adversos , Hipnóticos e Sedativos/farmacocinética , Hipnóticos e Sedativos/uso terapêutico , Infusões Intravenosas/métodos , Masculino , Midazolam/efeitos adversos , Midazolam/farmacocinética , Midazolam/uso terapêutico , Adulto Jovem
5.
Artigo em Inglês | MEDLINE | ID: mdl-31636065

RESUMO

GLS4 is a novel inhibitor of the hepatitis B virus (HBV) capsid assembly with inhibitory activities against nucleot(s)ide-resistant HBV strains. This study investigated the pharmacokinetics, safety, and tolerability of GLS4 and the effects of food and ritonavir in healthy adults. GLS4 was administered in a single-ascending-dose study over 1 to 240 mg and multiple-ascending-dose study that ranged from 30 mg once daily to 180 mg three times daily. The drug interaction study included sequential design (day 1 for 120 mg GLS4 alone, day 5 for 100 mg ritonavir alone, followed by 9 days of both drugs) and a placebo control (9 days of both 240 mg GLS4 and 100 mg ritonavir). The results showed that the steady-state trough concentration of multiple dosing of GLS4 alone was significantly lower than the 90% effective concentration of 55.7 ng/ml, even with increasing dosing frequency and dosage. An initial dose of 100 mg ritonavir significantly boosted plasma concentration at 24 h of 120 mg GLS4 from 2.40 to 49.8 ng/ml (geometric mean ratio, 20.7; 90% confidence interval, 17.0 to 25.3), while a milder effect was observed on the area under the curve from 0 to 24 h, with a 7.42-fold increase, and on the maximum concentration, with a 4.82-fold increase. The pharmacokinetics change in GLS4 persisted after 9 days of chronic dosing, with a trough concentration of 182 ng/ml. Both single and multiple doses of GLS4 up to 240 mg with or without ritonavir were well tolerated. These results support the investigation of a novel HBV treatment regimen containing GLS4 with 100 mg ritonavir added solely to enhance GLS4 concentrations in plasma. (This study was registered at the China Platform for Registry and Publicity of Drug Clinical Trials [http://www.chinadrugtrials.org.cn] under numbers CTR20132137 and CTR20150230.).


Assuntos
Capsídeo/efeitos dos fármacos , Capsídeo/metabolismo , Vírus da Hepatite B/patogenicidade , Ritonavir/uso terapêutico , Adolescente , Adulto , Alanina Transaminase/metabolismo , Antivirais/uso terapêutico , China , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Células Hep G2 , Hepatite B/tratamento farmacológico , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Montagem de Vírus/efeitos dos fármacos , Adulto Jovem
6.
Development ; 142(8): 1390-5, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25852197

RESUMO

Lysophosphatidic acid (LPA) is a bioactive phospholipid that is present in all tissues examined to date. LPA signals extracellularly via cognate G protein-coupled receptors to mediate cellular processes such as survival, proliferation, differentiation, migration, adhesion and morphology. These LPA-influenced processes impact many aspects of organismal development. In particular, LPA signalling has been shown to affect fertility and reproduction, formation of the nervous system, and development of the vasculature. Here and in the accompanying poster, we review the developmentally related features of LPA signalling.


Assuntos
Lisofosfolipídeos/metabolismo , Animais , Movimento Celular/fisiologia , Humanos , Sistema Nervoso/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Reprodução/fisiologia , Transdução de Sinais/fisiologia
7.
Int J Clin Pharmacol Ther ; 55(7): 558-566, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28406088

RESUMO

OBJECTIVE: To determine the pharmacokinetics (PK) of vancomycin in Chinese infant patients using a population pharmacokinetic (PKK) approach in order to provide support for individualized vancomycin therapy. METHOD: The data included 72 sets of steady-state peak and trough serum concentrations from 61 infants (0 - 1 years). PPK analysis was performed using the nonlinear mixed-effects modeling software. Inter- and intraindividual variability was estimated for the clearance and distribution volume of vancomycin. The potential effects of patient sex, postnatal age, postconceptional age, height, weight, body surface area, body mass index, alanine aminotransferase, aspartate aminotransferase, total protein, albumin, white blood cell count, serum creatinine, and concomitant medications on vancomycin PKs were explored. RESULTS: A one-compartment linear model with first-order elimination was used to describe the data. Weight and postnatal age had a significant influence on vancomycin clearance. The typical population parameter estimates of clearance and distribution volume were 0.46 L/h and 4.45 L, respectively. Goodness-of-fit plots and bootstrap outcomes confirmed the relatively good stability and prediction capability of the model. CONCLUSION: This study initially established a vancomycin PPK model to estimate individual PK parameters in Chinese infant patients.
.


Assuntos
Antibacterianos/farmacocinética , Modelos Biológicos , Vancomicina/farmacocinética , Administração Intravenosa , Fatores Etários , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Povo Asiático , Peso Corporal , China , Monitoramento de Medicamentos , Feminino , Humanos , Lactente , Recém-Nascido , Modelos Lineares , Masculino , Taxa de Depuração Metabólica , Estudos Retrospectivos , Vancomicina/administração & dosagem , Vancomicina/sangue
8.
PLoS Comput Biol ; 11(3): e1004122, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25816223

RESUMO

Gene repression by transcription factors, and glucocorticoid receptors (GR) in particular, is a critical, but poorly understood, physiological response. Among the many unresolved questions is the difference between GR regulated induction and repression, and whether transcription cofactor action is the same in both. Because activity classifications based on changes in gene product level are mechanistically uninformative, we present a theory for gene repression in which the mechanisms of factor action are defined kinetically and are consistent for both gene repression and induction. The theory is generally applicable and amenable to predictions if the dose-response curve for gene repression is non-cooperative with a unit Hill coefficient, which is observed for GR-regulated repression of AP1LUC reporter induction by phorbol myristate acetate. The theory predicts the mechanism of GR and cofactors, and where they act with respect to each other, based on how each cofactor alters the plots of various kinetic parameters vs. cofactor. We show that the kinetically-defined mechanism of action of each of four factors (reporter gene, p160 coactivator TIF2, and two pharmaceuticals [NU6027 and phenanthroline]) is the same in GR-regulated repression and induction. What differs is the position of GR action. This insight should simplify clinical efforts to differentially modulate factor actions in gene induction vs. gene repression.


Assuntos
Repressão Epigenética/genética , Modelos Genéticos , Fatores de Transcrição/genética , Biologia Computacional , Humanos , Cinética , Compostos Nitrosos , Fenantrolinas , Pirimidinas , Receptores de Glucocorticoides , Reprodutibilidade dos Testes
9.
Ther Drug Monit ; 38(3): 365-70, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26818624

RESUMO

BACKGROUND: Monohydroxycarbamazepine (MHD, 10-hydroxy-carbamazepine) is the main active metabolite of oxcarbazepine (OXC). The present study aims to investigate the relationship between plasma and saliva concentrations of MHD in Chinese children with epilepsy. METHODS: Plasma and saliva samples were collected and MHD levels were measured by high-performance liquid chromatography system. Linear regression analysis was conducted between the dose of OXC and saliva concentrations, between the dose of OXC and plasma concentrations, and between the saliva concentrations and plasma concentrations. Student's t-test was used for unpaired data. A one-way analysis of variance was used for analyzing co-medication in subgroups of patients. RESULTS: A total of 58 blood samples and 58 saliva samples were obtained from 52 pediatric epileptic patients, with a median age of 5.67 years (0.58-15 years, 23 males and 29 females). There was an apparent positive correlation between the plasma and saliva MHD concentrations [Y = 0.77x - 0.85 (n = 58), R = 0.908, P < 0.01]. MHD plasma and saliva concentrations were positively correlated to daily drug dose (r = 0.461 and 0.417; P < 0.01 respectively). The saliva/plasma MHD ratio was around 0.71 and had no significant difference with age, gender, and combined medications. When data were analyzed for subgroups (one group taking OXC as monotherapy, the second group taking OXC in add-on with non-enzyme-inducing antiepileptic drugs, and the third group taking OXC in add-on with hepatic-enzyme-inducing antiepileptic drugs or moderate inducers), no significant difference was found between plasma and saliva MHD concentrations in all the above 3 groups. CONCLUSIONS: High correlation between plasma and saliva MHD levels supported the use of saliva as an alternative to plasma for OXC monitoring in children with epilepsy.


Assuntos
Anticonvulsivantes/farmacocinética , Carbamazepina/análogos & derivados , Monitoramento de Medicamentos/métodos , Epilepsia/tratamento farmacológico , Adolescente , Anticonvulsivantes/administração & dosagem , Povo Asiático , Carbamazepina/administração & dosagem , Carbamazepina/farmacocinética , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Feminino , Humanos , Lactente , Modelos Lineares , Masculino , Oxcarbazepina , Estudos Prospectivos , Saliva/química
10.
Br J Clin Pharmacol ; 80(5): 1224-34, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25925501

RESUMO

The aim of the present meta-analysis was to determine the efficacy and safety of metformin for the treatment of women with gestational diabetes mellitus (GDM). We searched databases, including PubMed, Embase and the Cochrane Central Register of Controlled Trials, for randomized controlled trials (RCTs) comparing metformin and insulin treatments in women with GDM. We carried out statistical analyses using RevMan 2011 and used the Grading of Recommendations, Assessment, Development, and Evaluations profiler to rate the quality of evidence of the primary outcomes. We analysed eight studies involving 1592 subjects. Meta-analysis of the RCTs showed that metformin had statistically significant effects on pregnancy-induced hypertension [PIH; risk ratio (RR) 0.54; 95% confidence interval (CI) 0.31, 0.91]. However, its effects on neonatal hypoglycaemia (RR 0.80; 95% CI 0.62, 1.02), rate of large-for-gestational age infants (RR 0.77; 95% CI 0.55, 1.08), respiratory distress syndrome (RR 1.26; 95% CI 0.67, 2.37), phototherapy (RR 0.94; 95% CI 0.67, 1.31) and perinatal death (RR 1.01; 95% CI 0.11, 9.53) were not significant. Our analyses suggest that there is no clinically relevant difference in efficacy or safety between metformin and insulin; however, metformin may be a good choice for GDM because of the lower risk of PIH. The advantages of metformin in terms of glycaemic control, PIH incidence and gestational age at birth are unclear, and should be verified in further trials.


Assuntos
Diabetes Gestacional/tratamento farmacológico , Insulina/uso terapêutico , Metformina/efeitos adversos , Metformina/uso terapêutico , Feminino , Humanos , Hipertensão Induzida pela Gravidez/tratamento farmacológico , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Res Nurs Health ; 37(5): 367-78, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25155992

RESUMO

Dietary fiber supplements are used to manage fecal incontinence (FI), but little is known about the fiber type to recommend or the level of effectiveness of such supplements, which appears related to the fermentability of the fiber. The aim of this single-blind, randomized controlled trial was to compare the effects of three dietary fiber supplements (carboxymethylcellulose [CMC], gum arabic [GA], or psyllium) with differing levels of fermentability to a placebo in community-living individuals incontinent of loose/liquid feces. The primary outcome was FI frequency; secondary outcomes included FI amount and consistency, supplement intolerance, and quality of life (QoL). Possible mechanisms underlying supplement effects were also examined. After a 14-day baseline, 189 subjects consumed a placebo or 16 g total fiber/day of one of the fiber supplements for 32 days. FI frequency significantly decreased after psyllium supplementation versus placebo, in both intent-to-treat and per-protocol mixed model analyses. CMC increased FI frequency. In intent-to-treat analysis, the number of FI episodes/week after supplementation was estimated to be 5.5 for Placebo, 2.5 for Psyllium, 4.3 for GA, and 6.2 for CMC. Only psyllium consumption resulted in a gel in feces. Supplement intolerance was low. QoL scores did not differ among groups. Patients with FI may experience a reduction in FI frequency after psyllium supplementation, and decreased FI frequency has been shown to be an important personal goal of treatment for patients with FI. Formation of a gel in feces appears to be a mechanism by which residual psyllium improved FI.


Assuntos
Fibras na Dieta/administração & dosagem , Incontinência Fecal/dietoterapia , Carboximetilcelulose Sódica/administração & dosagem , Feminino , Géis , Goma Arábica/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Psyllium/administração & dosagem , Qualidade de Vida , Método Simples-Cego , Resultado do Tratamento
12.
Eur J Pharm Sci ; 192: 106663, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38056780

RESUMO

BACKGROUND: Brozopentyl Sodium (BZP), a novel agent for ischemic stroke, has shown promising results in preclinical pharmacological studies, prompting the initiation of the first-in-human investigation. PURPOSE: This study aimed to assess the safety, tolerability, and pharmacokinetic (PK) characteristics of BZP in Chinese healthy volunteers. METHODS: The study consisted of two parts. Part I was a single-center, randomized, single-blinded, placebo-controlled, single-ascending study with six BZP dose cohorts (SAD: 25, 50, 100, 200, 300, and 400 mg). Part II was a single-center, randomized, single-blinded, placebo-controlled, multi-dose- and dose-elevated study with three BZP dose cohorts (MAD: 50, 100, and 200 mg). Doses were administered once daily on days 1 and 7 and twice daily on days 2-6. The PK properties of BZP and its bioactive metabolites, BNBP, were assessed. Safety and tolerability evaluations were also conducted. RESULTS: In the SAD study, BZP reached peak plasma concentrations (Tmax) at the end of administration, with median Tmax values ranging from 1 to 1.03 h, while BNBP reached Tmax between 1.25 to 1.38 h. The terminal half-lives (T1/2) were approximately 8 h for BZP and 15 h for BNBP. In the MAD study, steady-state plasma concentrations of BZP were reached by day 5. There was minimal accumulation of both BZP and BNBP after 7 days of administration. The area under the plasma concentration-time curve from 0 to time of the last measurable concentration (AUC0-t) and maximum plasma drug concentration (Cmax) showed dose-proportional increases for BZP but not for BNBP in both study parts. Single and multiple doses of BZP demonstrated a good safety profile and were well-tolerated. CONCLUSION: BZP displayed safety, good tolerability and predictable PK characteristics following both single and multiple ascending intravenous administrations. These findings provide a basis for further clinical development of BZP for ischemic stroke patients.


Assuntos
AVC Isquêmico , Sódio , Humanos , Infusões Intravenosas , Voluntários Saudáveis , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , China
13.
Stem Cell Res Ther ; 15(1): 180, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38902824

RESUMO

BACKGROUND: Telomeres consist of repetitive DNA sequences at the chromosome ends to protect chromosomal stability, and primarily maintained by telomerase or occasionally by alternative telomere lengthening of telomeres (ALT) through recombination-based mechanisms. Additional mechanisms that may regulate telomere maintenance remain to be explored. Simultaneous measurement of telomere length and transcriptome in the same human embryonic stem cell (hESC) revealed that mRNA expression levels of UBQLN1 exhibit linear relationship with telomere length. METHODS: In this study, we first generated UBQLN1-deficient hESCs and compared with the wild-type (WT) hESCs the telomere length and molecular change at RNA and protein level by RNA-seq and proteomics. Then we identified the potential interacting proteins with UBQLN1 using immunoprecipitation-mass spectrometry (IP-MS). Furthermore, the potential mechanisms underlying the shortened telomeres in UBQLN1-deficient hESCs were analyzed. RESULTS: We show that Ubiquilin1 (UBQLN1) is critical for telomere maintenance in human embryonic stem cells (hESCs) via promoting mitochondrial function. UBQLN1 deficiency leads to oxidative stress, loss of proteostasis, mitochondria dysfunction, DNA damage, and telomere attrition. Reducing oxidative damage and promoting mitochondria function by culture under hypoxia condition or supplementation with N-acetylcysteine partly attenuate the telomere attrition induced by UBQLN1 deficiency. Moreover, UBQLN1 deficiency/telomere shortening downregulates genes for neuro-ectoderm lineage differentiation. CONCLUSIONS: Altogether, UBQLN1 functions to scavenge ubiquitinated proteins, preventing their overloading mitochondria and elevated mitophagy. UBQLN1 maintains mitochondria and telomeres by regulating proteostasis and plays critical role in neuro-ectoderm differentiation.


Assuntos
Proteínas Relacionadas à Autofagia , Células-Tronco Embrionárias Humanas , Mitocôndrias , Proteostase , Homeostase do Telômero , Telômero , Humanos , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Proteínas Relacionadas à Autofagia/metabolismo , Proteínas Relacionadas à Autofagia/genética , Mitocôndrias/metabolismo , Telômero/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Estresse Oxidativo , Dano ao DNA
14.
Nat Commun ; 15(1): 3310, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632249

RESUMO

Asian soybean rust (ASR), caused by Phakopsora pachyrhizi, is a devastating disease that is present in all major soybean-producing regions. The limited availability of resistant germplasm has resulted in a scarcity of commercial soybean cultivars that are resistant to the disease. To date, only the Chinese soybean landrace SX6907 has demonstrated an immune response to ASR. In this study, we present the isolation and characterization of Rpp6907-7 and Rpp6907-4, a gene pair that confer broad-spectrum resistance to ASR. Rpp6907-7 and Rpp6907-4 encode atypic nucleotide-binding leucine-rich repeat (NLR) proteins that are found to be required for NLR-mediated immunity. Genetic analysis shows that only Rpp6907-7 confers resistance, while Rpp6907-4 regulates Rpp6907-7 signaling activity by acting as a repressor in the absence of recognized effectors. Our work highlights the potential value of using Rpp6907 in developing resistant soybean cultivars.


Assuntos
Phakopsora pachyrhizi , Glycine max , Genes de Plantas , Doenças das Plantas/genética
15.
Int J Clin Pharmacol Ther ; 51(7): 568-75, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23611568

RESUMO

OBJECTIVES: The aim of this study is to investigate the population pharmacokinetics (PopPK) of cyclosporine (CsA) in the Chinese hematopoietic stem cell transplantation (HSCT) recipients for promoting the individualization of CsA administration. METHODS: A total of 887 retrospective drug monitoring data points were collected from 58 HSCT recipients. Whole blood samples were collected at predose (C0) and 2 hours (C2) post dose. The administration of CsA was intermittent intravenous infusion, continuous intravenous infusion and oral. Population modeling was performed using the NONMEM (nonlinear mixedeffect modeling) program. A one compartment pharmacokinetic model was used to fit the data. RESULTS: Body surface area (BSA), administration route and postoperative days were identified as significant covariates for clearance (CL) according to the final model: CL = 31.0 × (BSA/1.59)0.761 × (ROUT) × (POD), where ROUT was 1.91 if the administration route was intravenous infusion, otherwise it is equal to 1. The POD was 0.818, 0.753, 0.539, and 0.509 for posttransplant Days 0 - 10, 11 - 20, 21 - 30 and more than 30 days, respectively. Administration route was a significant covariate for volume (V) according to the final model: V = 192 × (ROUT), where ROUT was 4.10, 3.63 and 1 when the administration route was continuous intravenous infusion, intermittent intravenous infusion and oral. The other covariates were not identified as a significant effect on CsA pharmacokinetic parameters. CONCLUSION: Body surface area, administration route and postoperative days should be considered in individual pharmacotherapy of cyclosporine for HSCT patient to achieve the desired therapeutic target.


Assuntos
Ciclosporina/farmacocinética , Transplante de Células-Tronco Hematopoéticas , Imunossupressores/farmacocinética , Administração Oral , Adolescente , Adulto , Povo Asiático , Superfície Corporal , Criança , Pré-Escolar , China , Ciclosporina/administração & dosagem , Ciclosporina/sangue , Esquema de Medicação , Cálculos da Dosagem de Medicamento , Monitoramento de Medicamentos , Transplante de Células-Tronco Hematopoéticas/etnologia , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/sangue , Infusões Intravenosas , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Modelos Biológicos , Modelos Estatísticos , Dinâmica não Linear , Estudos Retrospectivos , Adulto Jovem
16.
Tree Physiol ; 43(6): 1042-1054, 2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-36892416

RESUMO

Vegetative and reproductive phase change and phenology are economically and ecologically important traits. Trees typically require several years of growth before flowering and, once mature, seasonal control of the transition to flowering and flower development is necessary to maintain vegetative meristems and for reproductive success. Members of two related gene subfamilies, FLOWERING LOCUST (FT) and TERMINAL FLOWER1 (TFL1)/CENTRORADIALIS (CEN)/BROTHER OF FT AND TFL1 (BFT), have antagonistic roles in flowering in diverse species and roles in vegetative phenology in trees, but many details of their functions in trees have yet to be resolved. Here, we used CRISPR/Cas9 to generate single and double mutants involving the five Populus FT and TFL1/CEN/BFT genes. The ft1 mutants exhibited wild-type-like phenotypes in long days and short days, but after chilling, to release dormancy, they showed delayed bud flush and GA3 could compensate for the ft1 mutation. After rooting and generating some phytomers in tissue culture, both cen1 and cen1ft1 mutants produced terminal as well as axillary flowers, indicating that the cen1 flowering phenotype is independent of FT1. The CEN1 showed distinct circannual expression patterns in vegetative and reproductive tissues and comparison with the expression patterns of FT1 and FT2 suggests that the relative levels of CEN1 compared with FT1 and FT2 regulate multiple phases of vegetative and reproductive seasonal development.


Assuntos
Proteínas de Plantas , Populus , Proteínas de Plantas/metabolismo , Populus/metabolismo , Sistemas CRISPR-Cas , Flores , Meristema/genética , Regulação da Expressão Gênica de Plantas
17.
Sci China Life Sci ; 66(2): 324-339, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36125668

RESUMO

Functional telomeres protect chromosome ends and play important roles in stem cell maintenance and differentiation. Short telomeres negatively impact germ cell development and can contribute to age-associated infertility. Moreover, telomere syndrome resulting from mutations of telomerase or telomere-associated genes exhibits short telomeres and reduced fertility. It remains elusive whether and how telomere lengths affect germ cell specification. We report that functional telomere is required for the coordinated germ cell and somatic cell fate decisions. Using telomerase gene Terc deficient mice as a model, we show that short telomeres restrain germ cell specification of epiblast cells but promote differentiation towards somatic lineage. Short telomeres increase chromatin accessibility to elevate TGFß and MAPK/ERK signaling for somatic cell differentiation. Notably, elevated Fst expression in TGFß pathway represses the BMP4-pSmad signaling pathway, thus reducing germ cell formation. Re-elongation of telomeres by targeted knock-in of Terc restores normal chromatin accessibility to suppress TGFß and MAPK signaling, thereby facilitating germ cell formation. Taken together, our data reveal that functional telomeres are required for germ cell specification by repressing TGFß and MAPK signaling.


Assuntos
Células Germinativas , Telômero , Animais , Camundongos , Cromatina/metabolismo , Células Germinativas/metabolismo , Telomerase/genética , Telomerase/metabolismo , Telômero/genética , Telômero/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia
18.
Adv Ther ; 40(8): 3434-3445, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37285081

RESUMO

INTRODUCTION: To investigate the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of tirzepatide in Chinese patients with type 2 diabetes (T2D). METHODS: In this phase 1, double-blind, placebo-controlled, multiple dose study, patients were randomized into one of two cohorts to receive once-weekly subcutaneous tirzepatide or placebo. The initial tirzepatide dose in both cohorts was 2.5 mg, which was increased by 2.5 mg every 4 weeks to a maximum final dose of 10.0 mg at week 16 (Cohort 1) or 15.0 mg at week 24 (Cohort 2). The primary outcome was the safety and tolerability of tirzepatide. RESULTS: Twenty-four patients were randomized (tirzepatide 2.5-10.0 mg: n = 10, tirzepatide 2.5-15.0 mg: n = 10, placebo: n = 4); 22 completed the study. The most frequently reported treatment-emergent adverse events (TEAEs) among patients receiving tirzepatide were diarrhea and decreased appetite; most TEAEs were mild and resolved spontaneously with no serious adverse events reported in the tirzepatide groups and one in the placebo group. The plasma concentration half-life of tirzepatide was approximately 5-6 days. Mean glycated hemoglobin (HbA1c) decreased over time from baseline in the 2.5-10.0 mg (- 2.4%) and 2.5-15.0 mg (- 1.6%) tirzepatide groups, at week 16 and week 24, respectively, but remained steady in patients receiving placebo. Body weight decreased from baseline by - 4.2 kg at week 16 in the tirzepatide 2.5-10.0 mg group and by - 6.7 kg at week 24 in the 2.5-15.0 mg group. Mean fasting plasma glucose levels fell from baseline by - 4.6 mmol/L in the tirzepatide 2.5-10.0 mg group at week 16 and by - 3.7 mmol/L at week 24 in the tirzepatide 2.5-15.0 mg group. CONCLUSIONS: Tirzepatide was well tolerated in this population of Chinese patients with T2D. The safety, tolerability, PK, and PD profile of tirzepatide support once-weekly dosing in this population. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT04235959.


Assuntos
Diabetes Mellitus Tipo 2 , Hipoglicemiantes , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Método Duplo-Cego , População do Leste Asiático , Hipoglicemiantes/uso terapêutico , Resultado do Tratamento
19.
Cochrane Database Syst Rev ; (2): CD008605, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22336848

RESUMO

BACKGROUND: Ovarian hyperstimulation syndrome (OHSS) is a complication resulting from administration of human chorionic gonadotrophin (hCG) in assisted reproduction technology (ART) treatment. Most case are mild, but forms of moderate or severe OHSS appear in 3% to 8% of in vitro fertilisation (IVF) cycles. Recently, the dopamine agonist cabergoline has been introduced as a secondary prevention intervention for OHSS in women at high risk of OHSS who are undergoing ART treatment. OBJECTIVES: To assess the effectiveness and safety of cabergoline in preventing ovarian hyperstimulation syndrome (OHSS) in high-risk women undergoing ART treatment. SEARCH METHODS: Major medical databases (Cochrane Menstrual Disorders and Subfertility Group Specialised Register of trials, CENTRAL (The Cochrane Library), MEDLINE, EMBASE and PsycINFO) were systematically searched for randomised controlled trials (RCTs) assessing the effect of cabergoline in preventing OHSS. Databases were searched up to September 2011. Registers of clinical trials, abstracts of scientific meetings and reference lists of included studies were searched. No language restrictions were applied. SELECTION CRITERIA: RCTs which compared cabergoline with placebo, no treatment or another intervention for preventing OHSS in high-risk women were considered for inclusion. Primary outcome measures included incidence of moderate or severe OHSS and live birth rate. Secondary endpoints were clinical pregnancy rate, multiple pregnancy rate, miscarriage rate and any other adverse effects of the treatment. DATA COLLECTION AND ANALYSIS: Two authors independently screened titles, abstracts and the full text of publications; extracted data; and assessed risk of bias. Any disagreements were resolved by consensus. Pooled results were reported as odds ratio (OR) and 95% confidence interval (95% CI) by the Mantel-Haenszel method. MAIN RESULTS: Only two trials involving 230 women met the inclusion criteria. Both studies had a moderate risk of bias. Oral cabergoline, 0.5 mg daily, was given as an intervention and compared with a matched placebo. A statistically significant reduction in OHSS was observed in the cabergoline treated group (OR 0.40, 95% CI 0.20 to 0.77; 2 RCTs, 230 women) with a number needed to treat (NTT) of 7. There was a statistically significant difference in the incidence of moderate OHSS, favouring cabergoline (OR 0.38, 95% CI 0.19 to 0.78; 2 RCTs, 230 women) but not in severe OHSS (OR 0.77, 95% CI 0.24 to 2.45; 2 RCTs, 230 women). There was no significant difference in the clinical pregnancy rate (OR 0.94, 95% CI 0.56 to 1.59; 2 RCTs, 230 women), miscarriage rate (OR 0.31, 95% CI 0.03 to 3.07; 1 RCT, 163 women) or any other adverse effects of the treatment (OR 2.07, 95% CI 0.56 to 7.70; 1 RCT, 67 women). However, no data on multiple pregnancy rate or live birth rate were reported in either trial. AUTHORS' CONCLUSIONS: Cabergoline appears to reduce the risk of OHSS in high-risk women, especially for moderate OHSS. The use of cabergoline does not affect the pregnancy outcome (clinical pregnancy rate, miscarriage rate), nor is there an increased risk of adverse events. Further research should consider the risk of administering cabergoline and the comparison between cabergoline and established treatments (such as intravenous albumin and coasting). Large, well-designed and well-executed RCTs that involve more clinical endpoints are necessary to further evaluate the role of cabergoline in OHSS prevention.


Assuntos
Agonistas de Dopamina/uso terapêutico , Ergolinas/uso terapêutico , Síndrome de Hiperestimulação Ovariana/prevenção & controle , Técnicas de Reprodução Assistida , Aborto Espontâneo/prevenção & controle , Administração Oral , Cabergolina , Agonistas de Dopamina/administração & dosagem , Ergolinas/administração & dosagem , Feminino , Humanos , Gravidez , Taxa de Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
Front Plant Sci ; 13: 805101, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35185983

RESUMO

Both the evolution of tree taxa and whole-genome duplication (WGD) have occurred many times during angiosperm evolution. Transcription factors are preferentially retained following WGD suggesting that functional divergence of duplicates could contribute to traits distinctive to the tree growth habit. We used gain- and loss-of-function transgenics, photoperiod treatments, and circannual expression studies in adult trees to study the diversification of three Populus FLOWERING LOCUS D-LIKE (FDL) genes encoding bZIP transcription factors. Expression patterns and transgenic studies indicate that FDL2.2 promotes flowering and that FDL1 and FDL3 function in different vegetative phenophases. Study of dominant repressor FDL versions indicates that the FDL proteins are partially equivalent in their ability to alter shoot growth. Like its paralogs, FDL3 overexpression delays short day-induced growth cessation, but also induces distinct heterochronic shifts in shoot development-more rapid phytomer initiation and coordinated delay in both leaf expansion and the transition to secondary growth in long days, but not in short days. Our results indicate that both regulatory and protein coding sequence variation contributed to diversification of FDL paralogs that has led to a degree of specialization in multiple developmental processes important for trees and their local adaptation.

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