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1.
J Trauma Stress ; 36(3): 628-641, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37155933

RESUMO

Despite the therapeutic needs of aging Holocaust survivors, no randomized controlled trial (RCT) of psychotherapy exists for this population, with very few on older adults in general. This RCT aimed to compare the efficacy of Life Review Therapy for Holocaust survivors (LRT-HS) relative to a supportive control group. Holocaust survivors with a probable diagnosis of full or subsyndromal posttraumatic stress disorder (PTSD) or depressive disorder were included. Exclusion criteria were probable dementia, acute psychotic disorder, and acute suicidality. The predefined primary endpoint was the course of PTSD symptom scores. In total, 49 of 79 consecutive individuals assessed for eligibility were randomized and included in the intent-to-treat analyses (LRT-HS: n = 24, control: n = 25; Mage = 81.5 years, SD = 4.81, 77.6% female). Linear mixed models revealed no statistically significant superiority of LRT-HS for PTSD symptoms at posttreatment, with moderate effect sizes, Time x Condition interaction: t(75) = 1.46, p = .148, dwithin = 0.70, dbetween = 0.41, but analyses were significant at follow-up, with large effect sizes, t(79) = 2.89, p = .005, dwithin = 1.20, dbetween = 1.00. LRT-HS superiority for depression was observed at posttreatment, t(73) = 2.58, p = .012, but not follow-up, t(76) = 1.08, p = .282, with moderate effect sizes, dwithin = 0.46-0.60, dbetween = 0.53-0.70. The findings show that even in older age, PTSD and depression following exposure to multiple traumatic childhood events can be treated efficaciously using an age-appropriate treatment that includes structured life review and narrative exposure.


Assuntos
Holocausto , Transtornos de Estresse Pós-Traumáticos , Feminino , Humanos , Idoso , Criança , Idoso de 80 Anos ou mais , Masculino , Transtornos de Estresse Pós-Traumáticos/terapia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Psicoterapia , Sobreviventes
2.
Bioengineering (Basel) ; 10(3)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36978728

RESUMO

In this study, we aimed to evaluate the human placenta as a source of blood vessels that can be harvested for vascular graft fabrication in the submillimeter range. Our approach included graft modification to prevent thrombotic events. Submillimeter arterial grafts harvested from the human placenta were decellularized and chemically crosslinked to heparin. Graft performance was evaluated using a microsurgical arteriovenous loop (AVL) model in Lewis rats. Specimens were evaluated through hematoxylin-eosin and CD31 staining of histological sections to analyze host cell immigration and vascular remodeling. Graft patency was determined 3 weeks after implantation using a vascular patency test, histology, and micro-computed tomography. A total of 14 human placenta submillimeter vessel grafts were successfully decellularized and implanted into AVLs in rats. An appropriate inner diameter to graft length ratio of 0.81 ± 0.16 mm to 7.72 ± 3.20 mm was achieved in all animals. Grafts were left in situ for a mean of 24 ± 4 days. Decellularized human placental grafts had an overall patency rate of 71% and elicited no apparent immunological responses. Histological staining revealed host cell immigration into the graft and re-endothelialization of the vessel luminal surface. This study demonstrates that decellularized vascular grafts from the human placenta have the potential to serve as super-microsurgical vascular replacements.

3.
Leukemia ; 36(10): 2418-2429, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36056084

RESUMO

FLT3 tyrosine kinase inhibitor (TKI) therapy evolved into a standard therapy in FLT3-mutated AML. TKI resistance, however, develops frequently with poor outcomes. We analyzed acquired TKI resistance in AML cell lines by multilayered proteome analyses. Leupaxin (LPXN), a regulator of cell migration and adhesion, was induced during early resistance development, alongside the tyrosine kinase PTK2B which phosphorylated LPXN. Resistant cells differed in cell adhesion and migration, indicating altered niche interactions. PTK2B and LPXN were highly expressed in leukemic stem cells in FLT3-ITD patients. PTK2B/FAK inhibition abrogated resistance-associated phenotypes, such as enhanced cell migration. Altered pathways in resistant cells, assessed by nascent proteomics, were largely reverted upon PTK2B/FAK inhibition. PTK2B/FAK inhibitors PF-431396 and defactinib synergized with different TKIs or daunorubicin in FLT3-mutated AML. Midostaurin-resistant and AML cells co-cultured with mesenchymal stroma cells responded particularly well to PTK2B/FAK inhibitor addition. Xenograft mouse models showed significant longer time to leukemia symptom-related endpoint upon gilteritinib/defactinib combination treatment in comparison to treatment with either drug alone. Our data suggest that the leupaxin-PTK2B axis plays an important role in acquired TKI resistance in AML. PTK2B/FAK inhibitors act synergistically with currently used therapeutics and may overcome emerging TKI resistance in FLT3-mutated AML at an early timepoint.


Assuntos
Leucemia Mieloide Aguda , Inibidores de Proteínas Quinases , Animais , Benzamidas , Linhagem Celular Tumoral , Daunorrubicina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Quinase 2 de Adesão Focal/genética , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Camundongos , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/genética , Proteoma/genética , Pirazinas , Sulfonamidas , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/uso terapêutico
4.
Psychotherapy (Chic) ; 59(4): 521-532, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34941339

RESUMO

Having reached the last phase of their lives, many Holocaust survivors (HS) experience an increase in vulnerability. Despite their remarkable ability to adapt, the process of aging presents them with new challenges, often leading to an increased need for therapy. This is made all the more difficult by the fact that there is little research on trauma therapy in old age. To date, no randomized controlled study has been carried out to examine the effectiveness of psychotherapy in HS. The present case studies report the implementation of life review therapy (LRT-HS) undertaken with two female HS with symptoms of post-traumatic stress disorder (PTSD). The mixed-methods approach sheds light to their individual therapy courses and potential mechanisms of change. Both therapies took place in the context of a randomized controlled study evaluating the efficacy of LRT-HS. This integrative, narrative therapy approach answers the natural need of elderly people to look back on their lives. Patients received about 20 sessions of LRT-HS, including a structured life review, narrative exposure, as well as cognitive and behavioral elements. Patient 1 showed reliable to clinically significant improvements on several quantitative symptom levels and with consistent qualitative findings (e.g., semistructured therapist interview). Symptoms of Patient 2 remained mostly unchanged, while life satisfaction and posttraumatic growth reliably improved and qualitative measures pointed to a reduction of suffering. The studies illustrate that reminiscence can be used in adaptive ways even after the experience of massive traumatization. The coexistence of resilience and vulnerability, complex individual symptom profiles, and influencing factors are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Holocausto , Transtornos de Estresse Pós-Traumáticos , Humanos , Feminino , Idoso , Holocausto/psicologia , Sobreviventes/psicologia , Transtornos de Estresse Pós-Traumáticos/terapia , Transtornos de Estresse Pós-Traumáticos/psicologia , Psicoterapia/métodos , Ansiedade
5.
Front Psychol ; 12: 633049, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33776855

RESUMO

This study adapted and tested the efficacy of the Red-Light Purple-Light (RLPL) games for improving executive function (EF) skills in preprimary classrooms in Nairobi, Kenya. A cluster randomized controlled trial was used to evaluate the efficacy of the adapted RLPL intervention. Specifically, 24 centers (including 48 classrooms) were randomized to the RLPL or a wait-list control condition. Consistent with previous studies, participating classrooms delivered 16 lessons across an 8-week intervention period. A total of 479 children were recruited into the study. After exclusions based on child age and data quality, 451 and 404 children (90% retention) had completed computerized assessments of EF skills at pre- and posttest assessments, respectively. Children in the RLPL centers did not demonstrate any improvements in EF skills relative to their peers in the wait-list control condition (Cohen's ds = -0.14 to 0.03, all ps > 0.20). Exploratory tests of moderators (language of assessment, grade, school type, baseline ability) were also all null. Results are discussed with respect to measurement limitations and contextual factors that may explain the null results of RLPL on EF skills in young children in Kenya.

6.
Nat Commun ; 12(1): 106, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436597

RESUMO

Microplastics are increasingly recognized as ubiquitous global contaminants, but questions linger regarding their source, transport and fate. We document the widespread distribution of microplastics in near-surface seawater from 71 stations across the European and North American Arctic - including the North Pole. We also characterize samples to a depth of 1,015 m in the Beaufort Sea. Particle abundance correlated with longitude, with almost three times more particles in the eastern Arctic compared to the west. Polyester comprised 73% of total synthetic fibres, with an east-to-west shift in infra-red signatures pointing to a potential weathering of fibres away from source. Here we suggest that relatively fresh polyester fibres are delivered to the eastern Arctic Ocean, via Atlantic Ocean inputs and/or atmospheric transport from the South. This raises further questions about the global reach of textile fibres in domestic wastewater, with our findings pointing to their widespread distribution in this remote region of the world.

7.
Bioorg Med Chem ; 28(20): 115698, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33069080

RESUMO

A series of allosteric kidney-type glutaminase (GLS) inhibitors possessing a mercaptoethyl (SCH2CH2) linker were synthesized in an effort to further expand the structural diversity of chemotypes derived from bis-2-(5-phenylacetamido-1,3,4-thiadiazol-2-yl)ethyl sulfide (BPTES), a prototype allosteric inhibitor of GLS. BPTES analog 3a with a mercaptoethyl linker between the two thiadiazole rings was found to potently inhibit GLS with an IC50 value of 50 nM. Interestingly, the corresponding derivative with an n-propyl (CH2CH2CH2) linker showed substantially lower inhibitory potency (IC50 = 2.3 µM) while the derivative with a dimethylsulfide (CH2SCH2) linker showed no inhibitory activity at concentrations up to 100 µM, underscoring the critical role played by the mercaptoethyl linker in the high affinity binding to the allosteric site of GLS. Additional mercaptoethyl-linked compounds were synthesized and tested as GLS inhibitors to further explore SAR within this scaffold including derivatives possessing a pyridazine as a replacement for one of the two thiadiazole moiety.


Assuntos
Derivados de Benzeno/farmacologia , Inibidores Enzimáticos/farmacologia , Glutaminase/antagonistas & inibidores , Rim/enzimologia , Compostos de Sulfidrila/farmacologia , Sítio Alostérico/efeitos dos fármacos , Derivados de Benzeno/síntese química , Derivados de Benzeno/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Glutaminase/metabolismo , Humanos , Estrutura Molecular , Solubilidade , Relação Estrutura-Atividade , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/química
8.
Eur J Psychotraumatol ; 11(1): 1717156, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32128042

RESUMO

Background: After a potentially traumatic event (PTE), children often show symptoms of acute stress disorder (ASD), which may evolve into posttraumatic stress (PTS) disorder. A growing body of literature has employed latent class analysis (LCA) to disentangle the complex structure underlying PTS symptomatology, distinguishing between homogeneous subgroups based on PTS presentations. So far, little is known about subgroups or classes of ASD reactions in trauma-exposed children. Objective: Our study aimed to identify latent classes of ASD symptoms in children exposed to a single-incident PTE and to identify predictors of class membership (gender, age, cultural background, parental education, trauma type, and trauma history). Method: A sample of 2287 children and adolescents (5-18 years) was derived from the Prospective studies of Acute Child Trauma and Recovery (PACT/R) Data Archive, an international archive including studies from the USA, UK, Australia, and Switzerland. LCA was used to determine distinct subgroups based on ASD symptoms. Predictors of class membership were examined using a three-step approach. Results: Our LCA yielded a three-class solution: low (42%), intermediate (43%) and high (15%) ASD symptom severity that differed in terms of impairment and number of endorsed ASD symptoms. Compared to the low symptoms class, children in the intermediate or high severity class were more likely to be of female gender, be younger of age, have parents who had not completed secondary education, and be exposed to a road traffic accident or interpersonal violence (vs. an unintentional injury). Conclusions: These findings provide new information on children at risk for ASD after single-incident trauma, based on a unique set of international data. Classifying children based on latent symptom profiles helps to identify target groups for prevention and intervention after exposure to a PTE.


Antecedentes: después de un evento potencialmente traumático (EPT), los niños a menudo muestran síntomas de trastorno de estrés agudo (TEA), el cual, puede evolucionar a un trastorno de estrés postraumático (TEPT). Un creciente cuerpo de literatura ha empleado el análisis de clase latente (LCA por sus siglas en ingles) para desenredar la compleja estructura subyacente a la sintomatología de TEPT, distinguiendo entre subgrupos homogéneos basados en presentaciones de TEPT. Hasta ahora, se sabe poco sobre los subgrupos o clases de reacciones TEA en niños expuestos a traumas.Objetivo: Nuestro estudio tuvo como objetivo identificar clases latentes de síntomas de TEA en niños expuestos a un solo incidente de EPT e identificar predictores de pertenencia a la clase (género, edad, antecedentes culturales, educación de los padres, tipo de trauma e historial de trauma).Método: se obtuvo una muestra de 2287 niños y adolescentes (5­18 años) de los estudios Prospectivos del Archivo de Datos de recuperación y Trauma Infantil agudo (PACT/R, en sus siglas en inglés), un archivo internacional que incluye estudios de Estados Unidos, Reino Unido, Australia y Suiza. Se utilizó LCA para determinar distintos subgrupos basados en los síntomas de TEA. Los predictores de pertenencia a la clase se examinaron mediante análisis de regresión logística ponderada.Resultados: Nuestro LCA arrojó una solución de tres clases: gravedad de los síntomas de TEA baja (42%), intermedia (43%) y alta (15%) que difería en términos de deterioro y número de síntomas de TEA atribuidos. En comparación con la clase baja e intermedia, los niños en la clase de gravedad alta tenían más probabilidades de ser de género femenino, de menor edad, tener padres que no habían completado la educación secundaria y estar expuestos a la violencia interpersonal (versus a eventos médicos no interpersonales). Pertenecer a una minoría étnica se asoció con la pertenencia a la clase de "síntomas intermedios" en comparación con la clase de "síntomas bajos".Conclusiones: Estos hallazgos brindan nueva información sobre los niños en riesgo de TEA después de un incidente traumático único, en base a un conjunto único de datos internacionales. La clasificación de los niños según los perfiles de síntomas latentes ayuda a identificar los grupos objetivo para la prevención e intervención después de la exposición a un EPT.

9.
Aging Ment Health ; 24(4): 525-549, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-30522330

RESUMO

Objectives: Survivors of the Holocaust have reached an age during which it is common for them to look back on their lives. Previous research has shown that reminiscence can take on either adaptive ('self-positive') or detrimental ('self-negative') forms, which in turn are differently linked to psychological well-being. Thus, the question of "why" and "how" Holocaust survivors recall their autobiographical memories may hold important information about the underlying coping processes at play. This review aims to give insight into the current state of research on these questions.Method: A systematic literature search was conducted, looking for articles reporting quantitative and qualitative research on reminiscence and narrative styles, life review and well-being of Holocaust survivors. A methodological quality assessment was undertaken.Results: 23 articles met the criteria for inclusion. These articles focused either on reminiscence functions or on content and structure of life narratives. Such autobiographical reports were shaped by the experience of Holocaust. However, actual well-being was particularly determined by positive life events. Studies found evidence for resilience and ongoing effort to integrate the past into a coherent review. The link between reminiscence and health remains stable even after massive trauma. Contextual influences (such as culture) and age are discussed as possible covariates.Conclusions: The results show that Holocaust survivors are able to use reminiscence in a functional way, though they are increasingly more vulnerable as they reach very old age. The link between past suffering and present well-being gets stronger with age. Other stressful life experiences after the Holocaust must be considered as exacerbating factors. This review also presents the implications for therapy and open research questions are discussed.


Assuntos
Holocausto , Memória Episódica , Sobreviventes , Adaptação Psicológica , Humanos , Rememoração Mental , Narração
10.
Sci Rep ; 9(1): 11516, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395909

RESUMO

The alveolar bone provides structural support against compressive and tensile forces generated during mastication as well as during orthodontic treatment. To avoid abnormal alveolar bone resorption and tooth loss, a balanced bone turnover by bone-degrading osteoclasts and bone-generating osteoblasts is of great relevance. Unlike its contradictory role in regulating osteoclast and osteoblast cell differentiation, the TGF-ß/BMP-family member GDF15 is well known for its important functions in the regulation of cell metabolism, as well as cell fate and survival in response to cellular stress. Here, we provide first evidence for a potential role of GDF15 in translating mechanical stimuli into cellular changes in immature osteoblasts. We detected enhanced levels of GDF15 in vivo in periodontal ligament cells after the simulation of tooth movement in rat model system as well as in vitro in mechanically stressed human periodontal ligament fibroblasts. Moreover, mechanical stimulation enhanced GDF15 secretion by periodontal ligament cells and the stimulation of human primary osteoblast with GDF15 in vitro resulted in an increased transcription of osteogenic marker genes like RUNX2, osteocalcin (OCN) and alkaline phosphatase (ALP). Together, the present data emphasize for the first time a potential function of GDF15 in regulating differentiation programs of immature osteoblasts according to mechanical stimulation.


Assuntos
Fator 15 de Diferenciação de Crescimento/metabolismo , Osteogênese , Ligamento Periodontal/metabolismo , Estresse Mecânico , Transcrição Gênica , Animais , Células Cultivadas , Fibroblastos/metabolismo , Humanos , Ligamento Periodontal/citologia , Ratos , Ratos Wistar
11.
J Med Chem ; 62(1): 46-59, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29969024

RESUMO

Kidney-type glutaminase (GLS), the first enzyme in the glutaminolysis pathway, catalyzes the hydrolysis of glutamine to glutamate. GLS was found to be upregulated in many glutamine-dependent cancer cells. Therefore, selective inhibition of GLS has gained substantial interest as a therapeutic approach targeting cancer metabolism. Bis-2-[5-(phenylacetamido)-1,3,4-thiadiazol-2-yl]ethyl sulfide (BPTES), despite its poor physicochemical properties, has served as a key molecular template in subsequent efforts to identify more potent and drug-like allosteric GLS inhibitors. This review article provides an overview of the progress made to date in the development of GLS inhibitors and highlights the remarkable transformation of the unfavorable lead into "druglike" compounds guided by systematic SAR studies.


Assuntos
Inibidores Enzimáticos/química , Glutaminase/antagonistas & inibidores , Regulação Alostérica , Sítio Alostérico , Cristalografia por Raios X , Inibidores Enzimáticos/metabolismo , Glutaminase/metabolismo , Humanos , Simulação de Dinâmica Molecular , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Sulfetos/química , Sulfetos/metabolismo , Tiadiazóis/química , Tiadiazóis/metabolismo
12.
Sci Rep ; 8(1): 17715, 2018 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-30531925

RESUMO

Brain injury and inflammation induces a local release of extracellular vesicles (EVs) from astrocytes carrying proteins, RNAs, and microRNAs into the circulation. When these vesicles reach the liver, they stimulate the secretion of cytokines that mobilize peripheral immune cell infiltration into the brain, which can cause secondary tissue damage and impair recovery. Recent studies suggest that suppression of EV biosynthesis through neutral sphingomyelinase 2 (nSMase2) inhibition may represent a new therapeutic strategy. Unfortunately, currently available nSMase2 inhibitors exhibit low potency (IC50 ≥ 1 µM), poor solubility and/or limited brain penetration. Through a high throughput screening campaign of >365,000 compounds against human nSMase2 we identified 2,6-Dimethoxy-4-(5-Phenyl-4-Thiophen-2-yl-1H-Imidazol-2-yl)-Phenol (DPTIP), a potent (IC50 30 nM), selective, metabolically stable, and brain penetrable (AUCbrain/AUCplasma = 0.26) nSMase2 inhibitor. DPTIP dose-dependently inhibited EV release in primary astrocyte cultures. In a mouse model of brain injury conducted in GFAP-GFP mice, DPTIP potently (10 mg/kg IP) inhibited IL-1ß-induced astrocyte-derived EV release (51 ± 13%; p < 0.001). This inhibition led to a reduction of cytokine upregulation in liver and attenuation of the infiltration of immune cells into the brain (80 ± 23%; p < 0.01). A structurally similar but inactive analog had no effect in vitro or in vivo.


Assuntos
Astrócitos/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encefalite/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Esfingomielina Fosfodiesterase/antagonistas & inibidores , Animais , Astrócitos/metabolismo , Encéfalo/metabolismo , Linhagem Celular , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalite/metabolismo , Vesículas Extracelulares/efeitos dos fármacos , Vesículas Extracelulares/metabolismo , Células HEK293 , Humanos , Camundongos , Ratos , Regulação para Cima/efeitos dos fármacos
13.
J Med Chem ; 61(9): 3918-3929, 2018 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-29648826

RESUMO

Mebendazole (MBZ) was developed as a broad-spectrum anthelmintic but has recently shown efficacy as an anticancer agent. The use of MBZ for cancer, however, is challenging due to its poor solubility leading to poor bioavailability. Herein, we developed a prodrug approach with various N-linked promoieties including acyloxymethyl, aminoacyloxymethyl, and substituted phosphonooxymethyl in attempt to improve these characteristics. Compound 12, containing an (((((isopropoxycarbonyl)oxy)methoxy)phosphoryl)oxy)methyl promoiety, showed a >10 000-fold improvement in aqueous solubility. When evaluated in mice, 12 displayed a 2.2-fold higher plasma AUC0- t and a 1.7-fold improvement in brain AUC0- t with a calculated oral bioavailability of 52%, as compared to 24% for MBZ-polymorph C (MBZ-C), the most bioavailable polymorph. In dogs, 12 showed a 3.8-fold higher plasma AUC0- t with oral bioavailability of 41% compared to 11% for MBZ-C. In summary, we have identified a prodrug of MBZ with better physicochemical properties and enhanced bioavailability in both mice and dog.


Assuntos
Anti-Helmínticos/metabolismo , Mebendazol/metabolismo , Nitrogênio/química , Pró-Fármacos/química , Pró-Fármacos/farmacocinética , Água/química , Administração Oral , Animais , Disponibilidade Biológica , Cães , Estabilidade de Medicamentos , Masculino , Camundongos , Pró-Fármacos/administração & dosagem , Pró-Fármacos/metabolismo , Solubilidade , Relação Estrutura-Atividade , Distribuição Tecidual
14.
Biotechnol J ; 13(2)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29087627

RESUMO

The availability of clinical-scale downstream processing strategies for cell-based products presents a critical juncture between basic research and clinical development. Aqueous two-phase systems (ATPS) facilitate the label-free, scalable, and cost-effective separation of cells, and are a versatile tool for downstream processing of cell-based therapeutics. Here, we report the application of a previously developed robotic screening platform, here extended to enable a multiplexed high-throughput cell partitioning analysis in ATPS. We investigated the influence of polymer molecular weight and tie-line length on the resolution of five model cell lines in "charge-sensitive" polyethylene-glycol (PEG)-dextran ATPS. We show, how these factors influence cell partitioning, and that the combination of low molecular weight PEGs and high molecular weight dextrans enable the highest resolution of the five cell lines. Furthermore, we demonstrate that the separability of each cell line from the mixture is highly dependent on the polymer molecular weight composition and tie-line length. Using a countercurrent distribution model we demonstrate that our screenings yielded conditions that theoretically enable the isolation of four of the five cell lines with high purity (>99.9%) and yield.


Assuntos
Separação Celular , Polímeros/química , Células A549 , Animais , Linhagem Celular , Sobrevivência Celular , Dextranos/química , Fibroblastos/citologia , Humanos , Camundongos , Peso Molecular , Polietilenoglicóis/química , Ratos , Robótica
15.
Mol Pharm ; 14(10): 3248-3257, 2017 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-28763226

RESUMO

2-(Phosphonomethyl)pentanedioic acid (2-PMPA) is a potent and selective inhibitor of glutamate carboxypeptidase-II (GCPII) with efficacy in multiple neurological and psychiatric disease models, but its clinical utility is hampered by low brain penetration due to the inclusion of multiple acidic functionalities. We recently reported an improvement in the brain-to-plasma ratio of 2-PMPA after intranasal (IN) dosing in both rodents and primates. Herein, we describe the synthesis of several 2-PMPA prodrugs with further improved brain delivery of 2-PMPA after IN administration by masking of the γ-carboxylate. When compared to IN 2-PMPA in rats at 1 h post dose, γ-(4-acetoxybenzyl)-2-PMPA (compound 1) resulted in significantly higher 2-PMPA delivery to both plasma (4.1-fold) and brain (11-fold). Subsequent time-dependent evaluation of 1 also showed high brain as well as plasma 2-PMPA exposures with brain-to-plasma ratios of 2.2, 0.48, and 0.26 for olfactory bulb, cortex, and cerebellum, respectively, as well as an improved sciatic nerve to plasma ratio of 0.84. In contrast, IV administration of compound 1 resulted in similar plasma exposure of 2-PMPA versus the IN route (AUCIV: 76 ± 9 h·nmol/mL versus AUCIN: 99 ± 24 h·nmol/mL); but significantly lower nerve and brain tissue exposures with tissue-to-plasma ratios of 0.21, 0.03, 0.04, and 0.04 in nerve, olfactory bulb, cortex, and cerebellum, respectively. In primates, IN administration of 1 more than doubled 2-PMPA concentrations in the cerebrospinal fluid relative to previously reported levels following IN 2-PMPA. The results of these experiments provide a promising strategy for testing GCPII inhibition in neurological and psychiatric disorders.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Glutamato Carboxipeptidase II/antagonistas & inibidores , Fármacos Neuroprotetores/farmacologia , Compostos Organofosforados/farmacologia , Administração Intranasal , Administração Intravenosa , Animais , Líquido Cefalorraquidiano/efeitos dos fármacos , Ésteres/análise , Ésteres/química , Ésteres/farmacologia , Macaca mulatta , Masculino , Fármacos Neuroprotetores/análise , Fármacos Neuroprotetores/química , Compostos Organofosforados/análise , Compostos Organofosforados/química , Pró-Fármacos/análise , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Ratos , Ratos Wistar , Distribuição Tecidual
16.
J Med Chem ; 60(18): 7799-7809, 2017 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-28759215

RESUMO

4-Carboxy-α-[3-(hydroxyamino)-3-oxopropyl]-benzenepropanoic acid 1 is a potent hydroxamate-based inhibitor of glutamate carboxypeptidase II. In an attempt to improve its poor oral pharmacokinetics, we synthesized a series of prodrugs by masking its hydrophilic hydroxamate group. Prodrugs were evaluated for oral availability in mice and showed varying degree of plasma exposure to 1. Of these, para-acetoxybenzyl-based, 4-(5-(((4-acetoxybenzyl)oxy)amino)-2-carboxy-5-oxopentyl)benzoic acid, 12, provided 5-fold higher plasma levels of 1 compared to oral administration of 1 itself. Subsequently, para-acetoxybenzyl-based prodrugs with additional ester promoiety(ies) on carboxylate(s) were examined for their ability to deliver 1 to plasma. Isopropyloxycarbonyloxymethyl (POC) ester 30 was the only prodrug that achieved substantial plasma levels of 1. In vitro metabolite identification studies confirmed stability of the ethyl ester of benzoate while the POC group was rapidly hydrolyzed. At oral daily dose-equivalent of 3 mg/kg, 12 exhibited analgesic efficacy comparable to dose of 10 mg/kg of 1 in the rat chronic constrictive injury model of neuropathic pain.


Assuntos
Analgésicos/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Glutamato Carboxipeptidase II/antagonistas & inibidores , Ácidos Hidroxâmicos/uso terapêutico , Neuralgia/tratamento farmacológico , Pró-Fármacos/uso terapêutico , Administração Oral , Analgésicos/química , Analgésicos/farmacocinética , Analgésicos/farmacologia , Animais , Descoberta de Drogas , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Esterificação , Glutamato Carboxipeptidase II/metabolismo , Humanos , Ácidos Hidroxâmicos/química , Ácidos Hidroxâmicos/farmacocinética , Ácidos Hidroxâmicos/farmacologia , Masculino , Camundongos , Neuralgia/enzimologia , Pró-Fármacos/química , Pró-Fármacos/farmacocinética , Pró-Fármacos/farmacologia , Ratos , Ratos Sprague-Dawley
17.
J Med Chem ; 60(16): 7186-7198, 2017 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-28759224

RESUMO

Aberrant excitatory neurotransmission associated with overproduction of glutamate has been implicated in the development of HIV-associated neurocognitive disorders (HAND). The glutamine antagonist 6-diazo-5-oxo-l-norleucine (DON, 14) attenuates glutamate synthesis in HIV-infected microglia/macrophages, offering therapeutic potential for HAND. We show that 14 prevents manifestation of spatial memory deficits in chimeric EcoHIV-infected mice, a model of HAND. 14 is not clinically available, however, because its development was hampered by peripheral toxicities. We describe the synthesis of several substituted N-(pivaloyloxy)alkoxy-carbonyl prodrugs of 14 designed to circulate inert in plasma and be taken up and biotransformed to 14 in the brain. The lead prodrug, isopropyl 6-diazo-5-oxo-2-(((phenyl(pivaloyloxy)methoxy)carbonyl)amino)hexanoate (13d), was stable in swine and human plasma but liberated 14 in swine brain homogenate. When dosed systemically in swine, 13d provided a 15-fold enhanced CSF-to-plasma ratio and a 9-fold enhanced brain-to-plasma ratio relative to 14, opening a possible clinical path for the treatment of HAND.


Assuntos
Aminocaproatos/farmacologia , Compostos Azo/farmacologia , Diazo-Oxo-Norleucina/farmacologia , Transtornos Neurocognitivos/tratamento farmacológico , Nootrópicos/farmacologia , Pró-Fármacos/farmacologia , Aminocaproatos/administração & dosagem , Aminocaproatos/síntese química , Animais , Compostos Azo/administração & dosagem , Compostos Azo/síntese química , Sangue/metabolismo , Encéfalo/metabolismo , Diazo-Oxo-Norleucina/administração & dosagem , Estabilidade de Medicamentos , Feminino , Ácido Glutâmico/metabolismo , Glutaminase/antagonistas & inibidores , Infecções por HIV/complicações , Humanos , Masculino , Camundongos Endogâmicos C57BL , Transtornos Neurocognitivos/etiologia , Nootrópicos/administração & dosagem , Nootrópicos/síntese química , Pró-Fármacos/administração & dosagem , Pró-Fármacos/síntese química , Suínos , Carga Viral/efeitos dos fármacos
18.
Neuropsychologia ; 103: 12-19, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28669896

RESUMO

Our experience of time is often subject to distortions. For instance, time appears to slow down when unexpected events occur. Previous research has shown that the duration of infrequent stimuli - so-called oddballs - is commonly overestimated, an effect referred to as the temporal oddball effect. Oddballs are also known to cause a posterior P3, an event-related potential elicited by motivationally significant stimuli. Here, we propose that the temporal oddball effect and the posterior P3 share a common mechanism. We hypothesized that the P3 amplitude can be used to predict whether the duration of an oddball will be overestimated or not, even if this P3 precedes the offset of the stimulus. In our task, infrequent red targets were embedded in a series of white standards. All stimuli varied in duration and participants had to estimate the duration of the targets and some of the standards. Our data revealed that the duration of target oddballs, but not of standards, was overestimated and overestimations were associated with larger P3 amplitudes than correct short estimates. Because the P3 peaked before stimulus offset, this effect was independent of actual target oddball duration. Using multivariate pattern analysis, we provided direct evidence that it is indeed the P3 elicited by oddballs that caused this effect. Together, our results suggest that the temporal oddball effect is linked to the posterior P3. Based on these findings and established P3 theories, we propose that the common mechanism underlying both phenomena is a phasic norepinephrine response affecting the subjective experience of time.


Assuntos
Encéfalo/fisiologia , Potenciais Evocados/fisiologia , Percepção do Tempo/fisiologia , Adolescente , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Análise Multivariada , Testes Neuropsicológicos , Psicometria , Processamento de Sinais Assistido por Computador , Percepção Visual/fisiologia , Adulto Jovem
19.
J Control Release ; 263: 132-138, 2017 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-28159515

RESUMO

Here we evaluate the potential for local administration of a small molecule FOLH1/GCPII inhibitor 2-phosphonomethyl pentanedioic acid (2-PMPA) as a novel treatment for inflammatory bowel disease (IBD). We found that FOLH1/GCPII enzyme activity was increased in the colorectal tissues of mice with TNBS-induced colitis, and confirmed that 2-PMPA inhibited FOLH1/GCPII enzyme activity ex vivo. In order to maximize local enema delivery of 2-PMPA, we studied the effect of vehicle tonicity on the absorption of 2-PMPA in the colon. Local administration of 2-PMPA in a hypotonic enema vehicle resulted in increased colorectal tissue absorption at 30min compared to 2-PMPA administered in an isotonic enema vehicle. Furthermore, local delivery of 2-PMPA in hypotonic enema vehicle resulted in prolonged drug concentrations for at least 24h with minimal systemic exposure. Finally, daily treatment with the hypotonic 2-PMPA enema ameliorated macroscopic and microscopic symptoms of IBD in the TNBS-induced colitis mouse model, indicating the potential of FOLH1/GCPII inhibitors for the local treatment of IBD.


Assuntos
Colite/tratamento farmacológico , Enema , Glutamato Carboxipeptidase II/antagonistas & inibidores , Doenças Inflamatórias Intestinais/tratamento farmacológico , Compostos Organofosforados/administração & dosagem , Animais , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Glutamato Carboxipeptidase II/metabolismo , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Camundongos Endogâmicos BALB C , Compostos Organofosforados/sangue , Compostos Organofosforados/farmacocinética , Compostos Organofosforados/uso terapêutico , Ácido Trinitrobenzenossulfônico
20.
Biotechnol J ; 12(2)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27883271

RESUMO

The availability of preparative-scale downstream processing strategies for cell-based products presents a critical juncture between fundamental research and clinical development. Aqueous two-phase systems (ATPS) present a gentle, scalable, label-free, and cost-effective method for cell purification, and are thus a promising tool for downstream processing of cell-based therapeutics. Here, the application of a previously developed robotic screening platform that enables high-throughput cell partitioning analysis in ATPS is reported. In the present case study a purification strategy for two model cell lines based on high-throughput screening (HTS)-data and countercurrent distribution (CCD)-modeling, and validated the CCD-model experimentally is designed. The obtained data are shown an excellent congruence between CCD-model and experimental data, indicating that CCD-models in combination with HTS-data are a powerful tool in downstream process development. Finally, the authors are shown that while cell cycle phase significantly influences cell partitioning, cell type specific differences in surface properties are the main driving force in charge-dependent separation of HL-60 and L929 cells. In order to design a highly robust purification process it is, however, advisable to maintain constant growth conditions.


Assuntos
Biotecnologia/métodos , Ciclo Celular/fisiologia , Polietilenoglicóis/química , Água/química
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