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1.
J Exp Clin Cancer Res ; 42(1): 99, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37095531

RESUMO

BACKGROUND: MiT-Renal Cell Carcinoma (RCC) is characterized by genomic translocations involving microphthalmia-associated transcription factor (MiT) family members TFE3, TFEB, or MITF. MiT-RCC represents a specific subtype of sporadic RCC that is predominantly seen in young patients and can present with heterogeneous histological features making diagnosis challenging. Moreover, the disease biology of this aggressive cancer is poorly understood and there is no accepted standard of care therapy for patients with advanced disease. Tumor-derived cell lines have been established from human TFE3-RCC providing useful models for preclinical studies. METHODS: TFE3-RCC tumor derived cell lines and their tissues of origin were characterized by IHC and gene expression analyses. An unbiased high-throughput drug screen was performed to identify novel therapeutic agents for treatment of MiT-RCC. Potential therapeutic candidates were validated in in vitro and in vivo preclinical studies. Mechanistic assays were conducted to confirm the on-target effects of drugs. RESULTS: The results of a high-throughput small molecule drug screen utilizing three TFE3-RCC tumor-derived cell lines identified five classes of agents with potential pharmacological efficacy, including inhibitors of phosphoinositide-3-kinase (PI3K) and mechanistic target of rapamycin (mTOR), and several additional agents, including the transcription inhibitor Mithramycin A. Upregulation of the cell surface marker GPNMB, a specific MiT transcriptional target, was confirmed in TFE3-RCC and evaluated as a therapeutic target using the GPNMB-targeted antibody-drug conjugate CDX-011. In vitro and in vivo preclinical studies demonstrated efficacy of the PI3K/mTOR inhibitor NVP-BGT226, Mithramycin A, and CDX-011 as potential therapeutic options for treating advanced MiT-RCC as single agents or in combination. CONCLUSIONS: The results of the high-throughput drug screen and validation studies in TFE3-RCC tumor-derived cell lines have provided in vitro and in vivo preclinical data supporting the efficacy of the PI3K/mTOR inhibitor NVP-BGT226, the transcription inhibitor Mithramycin A, and GPNMB-targeted antibody-drug conjugate CDX-011 as potential therapeutic options for treating advanced MiT-RCC. The findings presented here should provide the basis for designing future clinical trials for patients with MiT-driven RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Inibidores de MTOR , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Translocação Genética , Fosfatidilinositol 3-Quinase , Glicoproteínas de Membrana/genética
2.
Clin Cancer Res ; 29(2): 472-487, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36322002

RESUMO

PURPOSE: PAX-fusion negative rhabdomyosarcoma (FN RMS) is driven by alterations in the RAS/MAP kinase pathway and is partially responsive to MEK inhibition. Overexpression of IGF1R and its ligands is also observed in FN RMS. Preclinical and clinical studies have suggested that IGF1R is itself an important target in FN RMS. Our previous studies revealed preclinical efficacy of the MEK1/2 inhibitor, trametinib, and an IGF1R inhibitor, BMS-754807, but this combination was not pursued clinically due to intolerability in preclinical murine models. Here, we sought to identify a combination of an MEK1/2 inhibitor and IGF1R inhibitor, which would be tolerated in murine models and effective in both cell line and patient-derived xenograft models of RAS-mutant FN RMS. EXPERIMENTAL DESIGN: Using proliferation and apoptosis assays, we studied the factorial effects of trametinib and ganitumab (AMG 479), a mAb with specificity for human and murine IGF1R, in a panel of RAS-mutant FN RMS cell lines. The molecular mechanism of the observed synergy was determined using conventional and capillary immunoassays. The efficacy and tolerability of trametinib/ganitumab was assessed using a panel of RAS-mutated cell-line and patient-derived RMS xenograft models. RESULTS: Treatment with trametinib and ganitumab resulted in synergistic cellular growth inhibition in all cell lines tested and inhibition of tumor growth in four of six models of RAS-mutant RMS. The combination had little effect on body weight and did not produce thrombocytopenia, neutropenia, or hyperinsulinemia in tumor-bearing SCID beige mice. Mechanistically, ganitumab treatment prevented the phosphorylation of AKT induced by MEK inhibition alone. Therapeutic response to the combination was observed in models without a mutation in the PI3K/PTEN axis. CONCLUSIONS: We demonstrate that combined trametinib and ganitumab is effective in a genomically diverse panel of RAS-mutated FN RMS preclinical models. Our data also show that the trametinib/ganitumab combination likely has a favorable tolerability profile. These data support testing this combination in a phase I/II clinical trial for pediatric patients with relapsed or refractory RAS-mutated FN RMS.


Assuntos
Rabdomiossarcoma , Humanos , Animais , Camundongos , Criança , Linhagem Celular Tumoral , Camundongos SCID , Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/genética , Rabdomiossarcoma/patologia , Inibidores de Proteínas Quinases/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno
3.
Ann Pharmacother ; 57(2): 127-132, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35684957

RESUMO

BACKGROUND: There is currently limited guidance from the American Diabetes Association regarding transitions of care for patients with diabetes. OBJECTIVE: This study's aim was to determine the impact of a diabetes-specific transitions of care clinic (TOCC) on hospital utilization and patient outcomes in recently discharged patients with diabetes. METHODS: This retrospective study evaluated patients seen by TOCC as compared with similar patients discharged from the study institution the year prior. The primary outcome was a composite of the number of unique patients with readmissions/emergency department (ED) visits within 30 days of discharge. Secondary outcomes included a subcomponent analysis of readmissions/ED visits, index hospital length of stay (LOS), and to describe clinical interventions made in clinic. This study was approved by the institutional review board of the Office of Responsible Research Practice at the Ohio State University Wexner Medical Center. RESULTS: There were 165 patients in the TOCC group and 157 in the control group based on the matching criteria. There was a statistically significant decrease in the primary outcome in the TOCC group versus the control group (18% vs 36%, P < 0.001). In evaluation of its subcomponents, there was a statically significant decrease in patients with readmissions (11% vs 26%, P < 0.001) but not ED visits (10% vs 17%, P = 0.096). The LOS for the TOCC group was shorter at 4 days versus 5 days in the control group (P = 0.055). CONCLUSIONS AND RELEVANCE: The implementation of a diabetes-specific TOCC can decrease both readmissions and ED visits and may impact hospital LOS. In addition, a TOCC can be used to identify gaps in preventive care. The results from this study may help support the creation of similar TOCC at other institutions.


Assuntos
Diabetes Mellitus , Readmissão do Paciente , Humanos , Estudos Retrospectivos , Alta do Paciente , Tempo de Internação , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Serviço Hospitalar de Emergência , Hospitais
4.
Prog Transplant ; 32(4): 292-299, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36039516

RESUMO

Introduction: Despite strong public support, organ donor registration rates (RR) continue to lag while need only grows. In the United States, the traditional registration site is the Department of Motor Vehicles (DMV), however Primary care provider (PCP) offices have been considered as alternate locations for increasing RR. Methods: Twelve PCP offices across 2 New York Counties were subjected to a control week where participants received only a registration opportunity and an intervention week with the addition of a motivational poster and informational brochure. Zip code level sociodemographic data were obtained for each site. RR from the DMV over the same period served as historical control. Results: There were 1292 participants in the control phase and 1099 in the experimental phase. New registration rate for the control was 33.8% (289/897); experimental phase 7.88% (61/769); DMV registration 21.02% (1902/9050). The intervention was associated with a significant decrease in registrations (OR 0.181 (95% CI 0.135-0.244, P < 0.001)). Offices were clustered based on sociodemographic factors and regressed in 2 clusters. Lower educational attainment was associated with lower registration in the first but not second cluster (OR = 0.948 (0.923-0.974, P < 0.001)). Conclusions: This study provided evidence that PCP offices were a feasible site for organ donor registration and calls into question the efficacy of written materials-only interventions for increasing organ donor RR. It reiterated the negative effect of lower educational attainment on registration and suggested future studies focus on more active methods of engagement.


Assuntos
Obtenção de Tecidos e Órgãos , Humanos , Estados Unidos , New York , Sistema de Registros , Doadores de Tecidos , Atenção Primária à Saúde
5.
J Transl Med ; 20(1): 375, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35982453

RESUMO

BACKGROUND: Several new generation CDK4/6 inhibitors have been developed and approved for breast cancer therapy in combination with endocrine therapeutics. Application of these inhibitors either alone or in combination in other solid tumors has been proposed, but no imaging biomarkers of response have been reported in non-breast cancer animal models. The purpose of this study was to evaluate 3'-[18F]fluoro-3'-deoxythymidine ([18F]FLT) Positron Emission Tomography (PET) as in vivo biomarker of response to palbociclib in a non-breast cancer model. METHODS: Twenty-four NSG mice bearing patient derived xenografts (PDX) of a well-characterized bladder tumor were randomized into 4 treatment groups: vehicle (n = 6); palbociclib (n = 6); temozolomide (n = 6); and palbociclib plus temozolomide (n = 6) and treated with two cycles of therapy or vehicle. Tumor uptake of [18F]FLT was determined by micro-PET/CT at baseline, 3 days, and 9 days post initiation of therapy. Following the second cycle of therapy, the mice were maintained until their tumors reached a size requiring humane termination. RESULTS: [18F]FLT uptake decreased significantly in the palbociclib and combination arms (p = 0.0423 and 0.0106 respectively at day 3 and 0.0012 and 0.0031 at day 9) with stable tumor volume. In the temozolomide arm [18F]FLT uptake increased with day 9 uptake significantly different than baseline (p = 0.0418) and progressive tumor growth was observed during the treatment phase. All groups exhibited progressive disease after day 22, 10 days following cessation of therapy. CONCLUSION: Significant decreases in [18F]FLT uptake as early as three days post initiation of therapy with palbociclib, alone or in combination with temozolomide, in this bladder cancer model correlates with an absence of tumor growth during therapy that persists until day 18 for the palbociclib group and day 22 for the combination group (6 days and 10 days) following cessation of therapy. These results support early modulation of [18F]FLT as an in vivo biomarker predictive of palbociclib therapy response in a non-breast cancer model.


Assuntos
Didesoxinucleosídeos , Neoplasias da Bexiga Urinária , Animais , Biomarcadores , Linhagem Celular Tumoral , Didesoxinucleosídeos/metabolismo , Humanos , Camundongos , Piperazinas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons/métodos , Piridinas , Temozolomida/uso terapêutico , Timidina , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/tratamento farmacológico
7.
World J Crit Care Med ; 10(4): 112-119, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34316446

RESUMO

Artificial intelligence (AI) and digital twin models of various systems have long been used in industry to test products quickly and efficiently. Use of digital twins in clinical medicine caught attention with the development of Archimedes, an AI model of diabetes, in 2003. More recently, AI models have been applied to the fields of cardiology, endocrinology, and undergraduate medical education. The use of digital twins and AI thus far has focused mainly on chronic disease management, their application in the field of critical care medicine remains much less explored. In neurocritical care, current AI technology focuses on interpreting electroencephalography, monitoring intracranial pressure, and prognosticating outcomes. AI models have been developed to interpret electroencephalograms by helping to annotate the tracings, detecting seizures, and identifying brain activation in unresponsive patients. In this mini-review we describe the challenges and opportunities in building an actionable AI model pertinent to neurocritical care that can be used to educate the newer generation of clinicians and augment clinical decision making.

8.
Mol Plant Pathol ; 22(3): 382-389, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33471956

RESUMO

Plant viruses typically have highly condensed genomes, yet the plant-pathogenic viruses Cassava brown streak virus, Ugandan cassava brown streak virus, and Euphorbia ringspot virus are unusual in encoding an enzyme not yet found in any other virus, the "house-cleaning" enzyme inosine triphosphatase. Inosine triphosphatases (ITPases) are highly conserved enzymes that occur in all kingdoms of life and perform a house-cleaning function by hydrolysing the noncanonical nucleotide inosine triphosphate to inosine monophosphate. The ITPases encoded by cassava brown streak virus and Ugandan cassava brown streak virus have been characterized biochemically and are shown to have typical ITPase activity. However, their biological role in virus infection has yet to be elucidated. Here we review what is known of viral-encoded ITPases and speculate on potential roles in infection with the aim of generating a greater understanding of cassava brown streak viruses, a group of the world's most devastating viruses.


Assuntos
Manihot/virologia , Doenças das Plantas/virologia , Potyviridae/enzimologia , Pirofosfatases/metabolismo , Potyviridae/genética , Pirofosfatases/genética , Proteínas Virais/genética , Proteínas Virais/metabolismo , Inosina Trifosfatase
9.
Mol Cancer Ther ; 19(8): 1589-1597, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32430490

RESUMO

The camptothecin derivatives topoisomerase I (TOP1) inhibitors, irinotecan and topotecan, are FDA approved for the treatment of colorectal, ovarian, lung and breast cancers. Because of the chemical instability of camptothecins, short plasma half-life, drug efflux by the multidrug-resistance ABC transporters, and the severe diarrhea produced by irinotecan, indenoisoquinoline TOP1 inhibitors (LMP400, LMP776, and LMP744), which overcome these limitations, have been developed and are in clinical development. Further modifications of the indenoisoquinolines led to the fluoroindenoisoquinolines, one of which, LMP517, is the focus of this study. LMP517 showed better antitumor activity than its parent compound LMP744 against H82 (small cell lung cancer) xenografts. Genetic analyses in DT40 cells showed a dual TOP1 and TOP2 signature with selectivity of LMP517 for DNA repair-deficient tyrosyl DNA phosphodiesterase 2 (TDP2)- and Ku70-knockout cells. RADAR assays revealed that LMP517, and to a lesser extent LMP744, induce TOP2 cleavage complexes (TOP2cc) in addition to TOP1ccs. Histone γH2AX detection showed that, unlike classical TOP1 inhibitors, LMP517 targets cells independently of their position in the cell cycle. Our study establishes LMP517 as a dual TOP1 and TOP2 inhibitor with therapeutic potential.


Assuntos
Indanos/uso terapêutico , Isoquinolinas/uso terapêutico , Terapia de Alvo Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Inibidores da Topoisomerase I/uso terapêutico , Inibidores da Topoisomerase II/uso terapêutico , Animais , Camptotecina/farmacologia , Carcinoma de Células Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Galinhas , DNA Topoisomerases Tipo I , DNA Topoisomerases Tipo II , Etoposídeo/farmacologia , Feminino , Histonas/análise , Humanos , Indanos/farmacologia , Isoquinolinas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Linfoma/patologia , Linfoma/veterinária , Camundongos , Camundongos Nus , Doenças das Aves Domésticas/patologia , Distribuição Aleatória , Proteínas Recombinantes/efeitos dos fármacos , Especificidade por Substrato , Ensaios Antitumorais Modelo de Xenoenxerto
10.
J Am Pharm Assoc (2003) ; 60(2): 391-396, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31813750

RESUMO

OBJECTIVE: This study aimed to evaluate the impact of a pharmacist-led postsurgical discharge medication reconciliation program in an accountable care organization-like setting. SETTING: Multidisciplinary primary care network in Central Ohio. PRACTICE DESCRIPTION: Ambulatory care pharmacists are integrated in a primary care network, which includes a centralized focus on assistance with population health metrics, along with an interdisciplinary team. PRACTICE INNOVATION: In May 2018, a pharmacist-led medication reconciliation postdischarge (MRP) program was initiated focused on a postsurgical discharge population. EVALUATION: A retrospective chart review was conducted to compare the 2 primary end points of overall MRP rates from 4 payers in 2017 and 2018, and the postsurgical MRP rates from May 25 to November 30 of 2017 and 2018. Secondary outcomes included description of pharmacist interventions in pharmacy-led service and 30-day readmission or emergency department (ED) utilization rates for postsurgical population. RESULTS: A total of 5837 hospitalizations were identified as eligible for overall MRP completion in 2017 (n = 2621) and 2018 (n = 3216). A 20% relative increase in overall MRP completion was reported in 2018 (P < 0.001). In 2017, 55.9% of postsurgical MRPs were completed. The implementation of the pharmacy-led MRP program led to a 41% relative increase in postsurgical MRP completion (78.9% in 2018, P < 0.001). Pharmacists completed 220 postsurgical MRPs in the 6-month study period, including 765 total recommendations for intervention and an average of 3 recommendations and 4 medication list updates per MRP. There was no statistically significant reduction in 30-day readmission and ED utilization rates in 2018 (6.8% in 2017 vs. 6.2% in 2018, P = 0.74). CONCLUSION: A pharmacy-led postsurgical discharge program led to an increase in MRP completion rates in the target postsurgical MRP population, which also positively affected the overall MRP completion rate. Pharmacists can be key players in the improvement and quality of MRP measures.


Assuntos
Farmacêuticos , Serviço de Farmácia Hospitalar , Assistência ao Convalescente , Humanos , Reconciliação de Medicamentos , Ohio , Alta do Paciente , Readmissão do Paciente , Indicadores de Qualidade em Assistência à Saúde , Estudos Retrospectivos
11.
Plant J ; 98(6): 988-999, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30790358

RESUMO

Plant asparaginyl endopeptidases (AEPs) are expressed as inactive zymogens that perform maturation of seed storage protein upon cleavage-dependent autoactivation in the low-pH environment of storage vacuoles. The AEPs have attracted attention for their macrocyclization reactions, and have been classified as cleavage or ligation specialists. However, we have recently shown that the ability of AEPs to produce either cyclic or acyclic products can be altered by mutations to the active site region, and that several AEPs are capable of macrocyclization given favorable pH conditions. One AEP extracted from Clitoria ternatea seeds (butelase 1) is classified as a ligase rather than a protease, presenting an opportunity to test for loss of cleavage activity. Here, making recombinant butelase 1 and rescuing an Arabidopsis thaliana mutant lacking AEP, we show that butelase 1 retains cleavage functions in vitro and in vivo. The in vivo rescue was incomplete, consistent with some trade-off for butelase 1 specialization toward macrocyclization. Its crystal structure showed an active site with only subtle differences from cleaving AEPs, suggesting the many differences in its peptide-binding region are the source of its efficient macrocyclization. All considered, it seems that either butelase 1 has not fully specialized or a requirement for autocatalytic cleavage is an evolutionary constraint upon macrocyclizing AEPs.


Assuntos
Arabidopsis/enzimologia , Clitoria/enzimologia , Cisteína Endopeptidases/metabolismo , Ligases/metabolismo , Arabidopsis/genética , Evolução Biológica , Catálise , Domínio Catalítico , Clitoria/genética , Cristalografia por Raios X , Ciclização , Cisteína Endopeptidases/química , Cisteína Endopeptidases/genética , Ligases/química , Ligases/genética , Modelos Estruturais , Mutação , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Recombinantes , Proteínas de Armazenamento de Sementes/genética , Proteínas de Armazenamento de Sementes/metabolismo
12.
Mol Cancer Ther ; 17(8): 1694-1704, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29748210

RESUMO

Contrary to other anticancer targets, topoisomerase I (TOP1) is targeted by only one chemical class of FDA-approved drugs: topotecan and irinotecan, the derivatives of the plant alkaloid, camptothecin. The indenoisoquinolines LMP400, LMP744, and LMP776 are novel noncamptothecin TOP1 inhibitors in clinical trial, which overcome the limitations of camptothecins. To further improve metabolic stability, their methoxy groups have been replaced by fluorine, as in the fluoroindenoisoquinolines NSC 781517 (LMP517), NSC 779135 (LMP135), and NSC 779134 (LMP134). We tested the induction and stability of TOP1 cleavage complexes (TOP1cc), and the induction and persistence of DNA damage measured by histone H2AX phosphorylation (γH2AX) compared with their parent compounds LMP744 and LMP776 in leukemia CCRF-CEM and colon carcinoma HCT116 cells. The fluoroindenoisoquinolines induced TOP1cc and γH2AX at nanomolar concentrations, and at higher levels than the parent indenoisoquinolines. The fluoroindenoisoquinoline LMP135 showed greater antitumor activity than topotecan in small-cell lung cancer cell H82 xenografts. It was also more potent than topotecan in the NCI-60 cancer cell line panel. Bioinformatics tools (http://discover.nci.nih.gov/cellminercdb) were used to investigate the following: (i) the correlations of fluoroindenoisoquinolines activity with other drugs, and (ii) genomic determinants of response in the NCI-60. The activity of the fluoroindenoisoquinolines was mostly correlated with camptothecin derivatives and the parent indenoisoquinolines, consistent with TOP1 targeting. Genomic analyses and activity assays in CCRF-CEM SLFN11-deleted cells showed that SLFN11 expression is a dominant determinant of response to LMP135. This study shows the potential value of the fluoroindenoisoquinolines for further development as novel anticancer agents targeting TOP1. Mol Cancer Ther; 17(8); 1694-704. ©2018 AACR.


Assuntos
Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Inibidores da Topoisomerase I/uso terapêutico , Animais , Camptotecina/farmacologia , Feminino , Humanos , Camundongos , Camundongos Nus , Inibidores da Topoisomerase I/farmacologia
13.
Elife ; 72018 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-29384475

RESUMO

Constrained, cyclic peptides encoded by plant genes represent a new generation of drug leads. Evolution has repeatedly recruited the Cys-protease asparaginyl endopeptidase (AEP) to perform their head-to-tail ligation. These macrocyclization reactions use the substrates amino terminus instead of water to deacylate, so a peptide bond is formed. How solvent-exposed plant AEPs macrocyclize is poorly understood. Here we present the crystal structure of an active plant AEP from the common sunflower, Helianthus annuus. The active site contained electron density for a tetrahedral intermediate with partial occupancy that predicted a binding mode for peptide macrocyclization. By substituting catalytic residues we could alter the ratio of cyclic to acyclic products. Moreover, we showed AEPs from other species lacking cyclic peptides can perform macrocyclization under favorable pH conditions. This structural characterization of AEP presents a logical framework for engineering superior enzymes that generate macrocyclic peptide drug leads.


Assuntos
Cisteína Endopeptidases/metabolismo , Helianthus/enzimologia , Helianthus/metabolismo , Peptídeos Cíclicos/metabolismo , Proteínas de Plantas/metabolismo , Ribossomos/metabolismo , Domínio Catalítico , Cristalografia por Raios X , Cisteína Endopeptidases/química , Conformação Proteica
14.
New Phytol ; 218(3): 923-928, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28322452

RESUMO

Contents Summary 923 I. Introduction 923 II. Plant AEPs with macrocyclizing ability 924 III. Mechanism of macrocyclization by AEPs 925 IV. Conclusions 927 Acknowledgements 927 References 927 SUMMARY: Plant asparaginyl endopeptidases (AEPs) are important for the post-translational processing of seed storage proteins via cleavage of precursor proteins. Some AEPs also function as peptide bond-makers during the biosynthesis of several unrelated classes of cyclic peptides, namely the kalata-type cyclic peptides, PawS-Derived Peptides and cyclic knottins. These three families of gene-encoded peptides have different evolutionary origins, but all have recruited AEPs for their maturation. In the last few years, the field has advanced rapidly, with the biochemical characterization of three plant AEPs capable of peptide macrocyclization, and insights have been gained from the first AEP crystal structures, albeit mammalian ones. Although the biochemical studies have improved our understanding of the mechanism of action, the focus now is to understand what changes in AEP sequence and structure enable some plant AEPs to perform macrocyclization reactions.


Assuntos
Cisteína Endopeptidases/metabolismo , Sequência de Aminoácidos , Ciclização , Cisteína Endopeptidases/química , Modelos Moleculares , Peptídeos Cíclicos/química , Peptídeos Cíclicos/metabolismo , Especificidade por Substrato
15.
J Appl Res Intellect Disabil ; 31(5): 760-767, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29152833

RESUMO

BACKGROUND: Current policy in the England suggests that people with intellectual disabilities should, where possible, access mainstream mental health services; this should include access to mainstream therapy services. It is likely that mainstream therapists will need training and support to work with people with intellectual disabilities. METHOD: Sixty-eight therapists working in an English Improving Access to Psychological Therapies (IAPT) service received one- or 2-day training on working with people with intellectual disabilities. Measures of confidence, general therapeutic self-efficacy and attitudes to people with intellectual disabilities' use of mainstream mental health services were completed pre-training, post-training and at 3-month follow-up; at which time, 12 participants were interviewed about the impact of the training on their practice. RESULTS: There was a significant positive change in all measures immediately post-training which was maintained at 3-month follow-up. CONCLUSIONS: Training considerations for mainstream therapists who may work with people with intellectual disabilities are discussed.


Assuntos
Atitude do Pessoal de Saúde , Competência Clínica , Currículo , Pessoal de Saúde/educação , Deficiência Intelectual/terapia , Psicoterapia/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
J Biol Chem ; 292(30): 12398-12411, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28536266

RESUMO

Seed storage proteins are both an important source of nutrition for humans and essential for seedling establishment. Interestingly, unusual napin-type 2S seed storage albumin precursors in sunflowers contain a sequence that is released as a macrocyclic peptide during post-translational processing. The mechanism by which such peptides emerge from linear precursor proteins has received increased attention; however, the structural characterization of intact precursor proteins has been limited. Here, we report the 3D NMR structure of the Helianthus annuus PawS1 (preproalbumin with sunflower trypsin inhibitor-1) and provide new insights into the processing of this remarkable dual-destiny protein. In seeds, PawS1 is matured by asparaginyl endopeptidases (AEPs) into the cyclic peptide SFTI-1 (sunflower trypsin inhibitor-1) and a heterodimeric 2S albumin. The structure of PawS1 revealed that SFTI-1 and the albumin are independently folded into well-defined domains separated by a flexible linker. PawS1 was cleaved in vitro with recombinant sunflower HaAEP1 and in situ using a sunflower seed extract in a way that resembled the expected in vivo cleavages. Recombinant HaAEP1 cleaved PawS1 at multiple positions, and in situ, its flexible linker was removed, yielding fully mature heterodimeric albumin. Liberation and cyclization of SFTI-1, however, was inefficient, suggesting that specific seed conditions or components may be required for in vivo biosynthesis of SFTI-1. In summary, this study has revealed the 3D structure of a macrocyclic precursor protein and provided important mechanistic insights into the maturation of sunflower proalbumins into an albumin and a macrocyclic peptide.


Assuntos
Helianthus/química , Peptídeos Cíclicos/química , Pré-Albumina/química , Peptídeos Cíclicos/metabolismo , Pré-Albumina/metabolismo , Conformação Proteica , Precursores de Proteínas/química , Precursores de Proteínas/metabolismo
17.
Plant Cell ; 29(3): 461-473, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28298518

RESUMO

Bowman-Birk Inhibitors (BBIs) are a well-known family of plant protease inhibitors first described 70 years ago. BBIs are known only in the legume (Fabaceae) and cereal (Poaceae) families, but peptides that mimic their trypsin-inhibitory loops exist in sunflowers (Helianthus annuus) and frogs. The disparate biosynthetic origins and distant phylogenetic distribution implies these loops evolved independently, but their structural similarity suggests a common ancestor. Targeted bioinformatic searches for the BBI inhibitory loop discovered highly divergent BBI-like sequences in the seedless, vascular spikemoss Selaginella moellendorffii Using de novo transcriptomics, we confirmed expression of five transcripts in S. moellendorffii whose encoded proteins share homology with BBI inhibitory loops. The most highly expressed, BBI3, encodes a protein that inhibits trypsin. We needed to mutate two lysine residues to abolish trypsin inhibition, suggesting BBI3's mechanism of double-headed inhibition is shared with BBIs from angiosperms. As Selaginella belongs to the lycopod plant lineage, which diverged ∼200 to 230 million years before the common ancestor of angiosperms, its BBI-like proteins imply there was a common ancestor for legume and cereal BBIs. Indeed, we discovered BBI sequences in six angiosperm families outside the Fabaceae and Poaceae. These findings provide the evolutionary missing links between the well-known legume and cereal BBI gene families.


Assuntos
Selaginellaceae/metabolismo , Inibidores da Tripsina/metabolismo , Evolução Molecular , Fabaceae/metabolismo , Magnoliopsida/metabolismo , Proteínas de Plantas/metabolismo , Poaceae/metabolismo
18.
Plant Physiol ; 174(1): 154-171, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28348066

RESUMO

The accumulation of proanthocyanidins is regulated by a complex of transcription factors composed of R2R3 MYB, basic helix-loop-helix, and WD40 proteins that activate the promoters of biosynthetic genes. In poplar (genus Populus), MYB134 is known to regulate proanthocyanidin biosynthesis by activating key flavonoid genes. Here, we characterize a second MYB regulator of proanthocyanidins, MYB115. Transgenic poplar overexpressing MYB115 showed a high-proanthocyanidin phenotype and reduced salicinoid accumulation, similar to the effects of MYB134 overexpression. Transcriptomic analysis of MYB115- and MYB134-overexpressing poplar plants identified a set of common up-regulated genes encoding proanthocyanidin biosynthetic enzymes and several novel uncharacterized MYB transcriptional repressors. Transient expression experiments demonstrated the capacity of both MYB134 and MYB115 to activate flavonoid promoters, but only in the presence of a basic helix-loop-helix cofactor. Yeast two-hybrid experiments confirmed the direct interaction of these transcription factors. The unexpected identification of dihydromyricetin in leaf extracts of both MYB115- and MYB134-overexpressing poplar led to the discovery of enhanced flavonoid B-ring hydroxylation and an increased proportion of prodelphinidins in proanthocyanidin of the transgenics. The dramatic hydroxylation phenotype of MYB115 overexpressors is likely due to the up-regulation of both flavonoid 3',5'-hydroxylases and cytochrome b5 Overall, this work provides new insight into the complexity of the gene regulatory network for proanthocyanidin synthesis in poplar.


Assuntos
Proteínas de Plantas/metabolismo , Populus/metabolismo , Proantocianidinas/biossíntese , Fatores de Transcrição/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas/classificação , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Populus/citologia , Populus/genética , Ligação Proteica , Fatores de Transcrição/classificação , Fatores de Transcrição/genética , Técnicas do Sistema de Duplo-Híbrido
19.
Subst Abus ; 37(1): 127-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26860334

RESUMO

BACKGROUND: Alcohol and opioid use disorders are common among adults under community supervision. Although several medications (medication-assisted treatment or MAT) are Food and Drug Administration (FDA)-approved to treat such disorders, they are underutilized with this population despite established effectiveness at decreasing substance use. This paper examines how community correctional agents' understanding of addiction and views of MAT influence their professional actions regarding addiction medications. METHODS: A total of 118 semistructured qualitative interviews were conducted with community correctional agents taking part in the CJ-DATS MATICCE implementation study across 20 parole/probation offices in 9 US states. Using grounded theory methodology and an iterative analytic approach, issues of role perception, views of MAT, current treatment referral, and community supervision practices were explored. RESULTS: Agents often had limited autonomy to make direct treatment referrals, regardless of their views of MAT, as they were required to follow court orders and their organization's policies and procedures. Within some organizations, community correctional agents held sufficient autonomy to make direct treatment referrals, with agents struggling to reconcile their desire to support their clients who needed MAT with concerns about the abuse potential of opioid agonist medications. Viewing MAT as a "treatment of last resort" was counterbalanced by the view that it was an effective evidence-based practice. Agents described how MAT impacted their ability to supervise clients and how their knowledge and understanding of MAT was directly influenced by watching their clients who were successful or unsuccessful on MAT. Even those agents who were more accepting of MAT were largely unsupportive of it long-term use. CONCLUSIONS: Community correctional agents' views of MAT were influenced by their understanding of addiction as well as their experiences supervising clients receiving treatment with medications, but whether or not MAT referrals were made was not always within their control.


Assuntos
Serviços de Saúde Comunitária/métodos , Conhecimentos, Atitudes e Prática em Saúde , Polícia/psicologia , Feminino , Humanos , Masculino , Metadona/uso terapêutico , Pessoa de Meia-Idade , Tratamento de Substituição de Opiáceos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Pesquisa Qualitativa , Encaminhamento e Consulta , Estados Unidos
20.
Prev Sci ; 17(2): 157-66, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26314868

RESUMO

This study replicated and extended previous evaluations of the Signs of Suicide (SOS) prevention program in a high school population using a more rigorous pre-test post-test randomized control design than used in previous SOS evaluations in high schools (Aseltine and DeMartino 2004; Aseltine et al. 2007). SOS was presented to an ethnically diverse group of ninth grade students in technical high schools in Connecticut. After controlling for the pre-test reports of suicide behaviors, exposure to the SOS program was associated with significantly fewer self-reported suicide attempts in the 3 months following the program. Ninth grade students in the intervention group were approximately 64% less likely to report a suicide attempt in the past 3 months compared with students in the control group. Similarly, exposure to the SOS program resulted in greater knowledge of depression and suicide and more favorable attitudes toward (1) intervening with friends who may be exhibiting signs of suicidal intent and (2) getting help for themselves if they were depressed or suicidal. In addition, high-risk SOS participants, defined as those with a lifetime history of suicide attempt, were significantly less likely to report planning a suicide in the 3 months following the program compared to lower-risk participants. Differential attrition is the most serious limitation of the study; participants in the intervention group who reported a suicide attempt in the previous 3 months at baseline were more likely to be missing at post-test than their counterparts in the control group.


Assuntos
Promoção da Saúde/normas , Avaliação de Programas e Projetos de Saúde , Instituições Acadêmicas , Prevenção do Suicídio , Adolescente , Connecticut , Feminino , Humanos , Masculino
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