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We previously discovered first-in-class multitargeted 5-substituted pyrrolo[3,2-d]pyrimidine antifolates that inhibit serine hydroxymethyltransferase 2 (SHMT2), resulting in potent in vitro and in vivo antitumor efficacies. In this report, we present crystallographic structures for SHMT2 in complex with an expanded series of pyrrolo[3,2-d]pyrimidine compounds with variations in bridge length (3-5 carbons) and the side chain aromatic ring (phenyl, thiophene, fluorine-substituted phenyl, and thiophene). We evaluated structural features of the inhibitor-SHMT2 complexes and correlations to inhibitor potencies (i.e., Kis), highlighting conserved polar contacts and identifying 5-carbon bridge lengths as key determinants of inhibitor potency. Based on the analysis of SHMT2 structural data, we investigated the impact of mutation of Tyr105 in SHMT2 kinetic analysis and studies with HCT116 cells with inducible expression of wild-type and Y105F SHMT2. Increased enzyme inhibition potency by the pyrrolo[3,2-d]pyrimidine inhibitors with Phe105 SHMT2 accompanied an increased growth inhibition of Phe105-expressing HCT116 cells compared to wild-type SHMT2. Pyrrolo[3,2-d]pyrimidine inhibitors with polyglutamate modifications were evaluated for potencies against SHMT2. We determined the crystal structures of SHMT2 in complex with our lead antifolate AGF347 lacking L-glutamate, or as a diglutamate and triglutamate, for comparison with parent AGF347. These data provide the first insights into the influence of antifolate polyglutamylation on SHMT2:inhibitor interactions. Collectively, our results provide new insights into the critical structural determinants of SHMT2 binding by pyrrolo[3,2-d]pyrimidine inhibitors as novel antitumor agents, as well as the first structural characterization of human SHMT2 in complex with polyglutamates of an SHMT2-targeted antifolate.
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Folate-dependent one-carbon (C1) metabolism encompasses distinct cytosolic and mitochondrial pathways connected by an interchange between serine, glycine and formate. In both the cytosol and mitochondria, folates exist as polyglutamates with polyglutamylation catalyzed by folylpolyglutamate synthetase (FPGS), including cytosolic and mitochondrial isoforms. Serine is metabolized by serine hydroxymethyltransferase (SHMT) 2 in the mitochondria and generates glycine and C1 units for cellular biosynthesis in the cytosol. AGF347 is a novel pyrrolo[3,2-d]pyrimidine antifolate that targets SHMT2 in the mitochondria, and SHMT1 and de novo purine biosynthesis in the cytosol. FPGS is expressed in primary pancreatic cancer specimens and FPGS levels correlate with in vitro efficacies of AGF347 toward human pancreatic cancer cells. MIA PaCa-2 pancreatic cancer cells with CRISPR knockout of FPGS were engineered to express doxycycline-inducible FPGS exclusively in the cytosol (cFPGS) or in both the cytosol and mitochondria (mFPGS). Folate and AGF347 accumulations increased in both the cytosol and mitochondria with increased mFPGS but were restricted to the cytosol with cFPGS. AGF347-Glu5 inhibited SHMT2 ~19-fold greater than AGF347 By metabolomics analysis, mFPGS stimulated the C1 flux from serine in the mitochondria and de novo purine and dTTP synthesis far greater than cFPGS. mFPGS enhanced in vitro inhibition of MIA PaCa-2 cell proliferation by AGF347 (~30-fold) more than cFPGS (~4.9-fold). Similar results were seen with other pyrrolo[3,2-d]pyrimidine antifolates (AGF291, AGF320); however, elevated mFPGS adversely impacted inhibition by the non-classical SHMT2/SHMT1 inhibitor, SHIN1. These results suggest a critical role of mFPGS levels in determining anti-tumor efficacies of mitochondrial-targeted pyrrolo[3,2-d]pyrimidine antifolates for pancreatic cancer. Significance Statement AGF347 is a novel pyrrolo[3,2-d]pyrimidine antifolate that targets serine hydroxymethyltransferase (SHMT) 2 in the mitochondria and SHMT1 and de novo purine biosynthesis in the cytosol. AGF347 accumulation increases with folylpolyglutamate synthetase (FPGS) levels in both the cytosol and mitochondria. Increased mitochondrial FPGS stimulated one-carbon metabolic fluxes in the cytosol and mitochondria and substantially enhanced in vitro inhibition of pancreatic cancer cells by AGF347 Mitochondrial FPGS levels play important roles in determining the anti-tumor efficacies of pyrrolo[3,2-d]pyrimidine antifolates for pancreatic cancer.
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Folate-dependent one-carbon (C1) metabolism is compartmentalized in the mitochondria and cytosol and is a source of critical metabolites for proliferating tumors. Mitochondrial C1 metabolism including serine hydroxymethyltransferase 2 (SHMT2) generates glycine for de novo purine nucleotide and glutathione biosynthesis and is an important source of NADPH, ATP, and formate, which affords C1 units as 10-formyl-tetrahydrofolate and 5,10-methylene-tetrahydrofolate for nucleotide biosynthesis in the cytosol. We previously discovered novel first-in-class multitargeted pyrrolo[3,2-d]pyrimidine inhibitors of SHMT2 and de novo purine biosynthesis at glycinamide ribonucleotide formyltransferase and 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase with potent in vitro and in vivo antitumor efficacy toward pancreatic adenocarcinoma cells. In this report, we extend our findings to an expanded panel of pancreatic cancer models. We used our lead analog AGF347 [(4-(4-(2-amino-4-oxo-3,4-dihydro-5H-pyrrolo[3,2-d]pyrimidin-5-yl)butyl)-2-fluorobenzoyl)-l-glutamic acid] to characterize pharmacodynamic determinants of antitumor efficacy for this series and demonstrated plasma membrane transport into the cytosol, uptake from cytosol into mitochondria, and metabolism to AGF347 polyglutamates in both cytosol and mitochondria. Antitumor effects of AGF347 downstream of SHMT2 and purine biosynthesis included suppression of mammalian target of rapamycin signaling, and glutathione depletion with increased levels of reactive oxygen species. Our results provide important insights into the cellular pharmacology of novel pyrrolo[3,2-d]pyrimidine inhibitors as antitumor compounds and establish AGF347 as a unique agent for potential clinical application for pancreatic cancer, as well as other malignancies. SIGNIFICANCE STATEMENT: This study establishes the antitumor efficacies of novel inhibitors of serine hydroxymethyltransferase 2 and of cytosolic targets toward a panel of clinically relevant pancreatic cancer cells and demonstrates the important roles of plasma membrane transport, mitochondrial accumulation, and metabolism to polyglutamates of the lead compound AGF347 to drug activity. We also establish that loss of serine catabolism and purine biosynthesis resulting from AGF347 treatment impacts mammalian target of rapamycin signaling, glutathione pools, and reactive oxygen species, contributing to antitumor efficacy.
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Antineoplásicos/farmacologia , Citosol/efeitos dos fármacos , Glicina Hidroximetiltransferase/antagonistas & inibidores , Mitocôndrias/efeitos dos fármacos , Pirimidinas/farmacologia , Pirróis/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Citosol/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Técnicas de Inativação de Genes , Glutationa/biossíntese , Glicina Hidroximetiltransferase/genética , Glicina Hidroximetiltransferase/metabolismo , Humanos , Leucovorina/análogos & derivados , Leucovorina/metabolismo , Mitocôndrias/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Nucleotídeos de Purina/biossíntese , Pirimidinas/química , Pirimidinas/uso terapêutico , Pirróis/química , Pirróis/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Serina/metabolismo , Tetra-Hidrofolatos/metabolismoRESUMO
We performed a systematic and meta analytic review of heart rate variability biofeedback (HRVB) for various symptoms and human functioning. We analyzed all problems addressed by HRVB and all outcome measures in all studies, whether or not relevant to the studied population, among randomly controlled studies. Targets included various biological and psychological problems and issues with athletic, cognitive, and artistic performance. Our initial review yielded 1868 papers, from which 58 met inclusion criteria. A significant small to moderate effect size was found favoring HRVB, which does not differ from that of other effective treatments. With a small number of studies for each, HRVB has the largest effect sizes for anxiety, depression, anger and athletic/artistic performance and the smallest effect sizes on PTSD, sleep and quality of life. We found no significant differences for number of treatment sessions or weeks between pretest and post-test, whether the outcome measure was targeted to the population, or year of publication. Effect sizes are larger in comparison to inactive than active control conditions although significant for both. HRVB improves symptoms and functioning in many areas, both in the normal and pathological ranges. It appears useful as a complementary treatment. Further research is needed to confirm its efficacy for particular applications.
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Desempenho Atlético , Sintomas Comportamentais/terapia , Biorretroalimentação Psicológica , Nível de Saúde , Frequência Cardíaca , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Desempenho Psicomotor , HumanosRESUMO
Pneumocystis pneumonia (PCP) caused by Pneumocystis jirovecii (pj) can lead to serious health consequences in patients with an immunocompromised system. Trimethoprim (TMP), used as first-line therapy in combination with sulfamethoxazole, is a selective but only moderately potent pj dihydrofolate reductase (pjDHFR) inhibitor, whereas non-clinical pjDHFR inhibitors, such as, piritrexim and trimetrexate are potent but non-selective pjDHFR inhibitors. To meet the clinical needs for a potent and selective pjDHFR inhibitor for PCP treatment, fourteen 6-substituted pyrido[3,2-d]pyrimidines were developed. Comparison of the amino acid residues in the active site of pjDHFR and human DHFR (hDHFR) revealed prominent amino acid differences which could be exploited to structurally design potent and selective pjDHFR inhibitors. Molecular modeling followed by enzyme assays of the compounds revealed 15 as the best compound of the series with an IC50 of 80â¯nM and 28-fold selectivity for inhibiting pjDHFR over hDHFR. Compound 15 serves as the lead analog for further structural variations to afford more potent and selective pjDHFR inhibitors.
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Antagonistas do Ácido Fólico/uso terapêutico , Pneumocystis carinii/patogenicidade , Pneumocystis/efeitos dos fármacos , Pirimidinas/uso terapêutico , Trimetoprima/uso terapêutico , Antagonistas do Ácido Fólico/farmacologia , Humanos , Modelos Moleculares , Pirimidinas/farmacologia , Relação Estrutura-Atividade , Trimetoprima/farmacologiaRESUMO
To combine the potency of trimetrexate (TMQ) or piritrexim (PTX) with the species selectivity of trimethoprim (TMP), target based design was carried out with the X-ray crystal structure of human dihydrofolate reductase (hDHFR) and the homology model of Pneumocystis jirovecii DHFR (pjDHFR). Using variation of amino acids such as Met33/Phe31 (in pjDHFR/hDHFR) that affect the binding of inhibitors due to their distinct positive or negative steric effect at the active binding site of the inhibitor, we designed a series of substituted-pyrrolo[2,3-d]pyrimidines. The best analogs displayed better potency (IC50) than PTX and high selectivity for pjDHFR versus hDHFR, with 4 exhibiting a selectivity for pjDHFR of 24-fold.
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Aminoácidos/química , Antibacterianos/farmacologia , Antagonistas do Ácido Fólico/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Antibacterianos/síntese química , Domínio Catalítico , Cristalografia por Raios X , Desenho de Fármacos , Ensaios Enzimáticos , Antagonistas do Ácido Fólico/síntese química , Antagonistas do Ácido Fólico/química , Antagonistas do Ácido Fólico/metabolismo , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Simulação de Acoplamento Molecular , Estrutura Molecular , Pneumocystis carinii/enzimologia , Ligação Proteica , Pirimidinas/síntese química , Pirimidinas/química , Pirimidinas/metabolismo , Pirróis/síntese química , Pirróis/química , Pirróis/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Tetra-Hidrofolato Desidrogenase/química , Tetra-Hidrofolato Desidrogenase/metabolismoRESUMO
The discovery, synthesis and biological evaluations of a series of nine N5-substituted-pyrrolo[3,2-d]pyrimidin-4-amines are reported. Novel compounds with microtubule depolymerizing activity were identified. Some of these compounds also circumvent clinically relevant drug resistance mechanisms (expression of P-glycoprotein and ßIII tubulin). Compounds 4, 5, and 8-13 were one to two-digit nanomolar (IC50) inhibitors of cancer cells in culture. Contrary to recent reports (Banerjee et al. J. Med. Chem.2018, 61, 1704-1718), the conformation of the most active compounds determined by 1H NMR and molecular modeling are similar to that reported previously and in keeping with recently reported X-ray crystal structures. Compound 11, freely water soluble as the HCl salt, afforded statistically significant inhibition of tumor growth in three xenograft models [MDA-MB-435, MDA-MB-231 and NCI/ADR-RES] compared with controls. Compound 11 did not display indications of animal toxicity and is currently slated for further preclinical development.
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Antineoplásicos/química , Antineoplásicos/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Pirróis/química , Pirróis/farmacologia , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Camundongos Nus , Microtúbulos/efeitos dos fármacos , Microtúbulos/metabolismo , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Estereoisomerismo , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/uso terapêuticoRESUMO
During animal development, cellular morphogenesis plays a fundamental role in determining the shape and function of tissues and organs. Identifying the components that regulate and drive morphogenesis is thus a major goal of developmental biology. The four-celled tip of the Caenorhabditis elegans male tail is a simple but powerful model for studying the mechanism of morphogenesis and its spatiotemporal regulation. Here, through a genome-wide post-embryonic RNAi-feeding screen, we identified 212 components that regulate or participate in male tail tip morphogenesis. We constructed a working hypothesis for a gene regulatory network of tail tip morphogenesis. We found regulatory roles for the posterior Hox genes nob-1 and php-3, the TGF-ß pathway, nuclear hormone receptors (e.g. nhr-25), the heterochronic gene blmp-1, and the GATA transcription factors egl-18 and elt-6. The majority of the pathways converge at dmd-3 and mab-3. In addition, nhr-25 and dmd-3/mab-3 regulate each others' expression, thus placing these three genes at the center of a complex regulatory network. We also show that dmd-3 and mab-3 negatively regulate other signaling pathways and affect downstream cellular processes such as vesicular trafficking (e.g. arl-1, rme-8) and rearrangement of the cytoskeleton (e.g. cdc-42, nmy-1, and nmy-2). Based on these data, we suggest that male tail tip morphogenesis is governed by a gene regulatory network with a bow-tie architecture.
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Proteínas de Caenorhabditis elegans , Caenorhabditis elegans/genética , Proteínas de Ligação a DNA , Morfogênese/genética , Interferência de RNA , Fatores de Transcrição , Animais , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Genes Homeobox , Masculino , Modelos Animais , Transdução de Sinais/genética , Cauda/crescimento & desenvolvimento , Cauda/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Multitargeted agents provide tumor selectivity with reduced drug resistance and dose-limiting toxicities. We previously described the multitargeted 6-substituted pyrrolo[3,2-d]pyrimidine antifolate 1 with activity against early- and late-stage pancreatic tumors with limited tumor selectivity. Structure-based design with our human serine hydroxymethyl transferase (SHMT) 2 and glycinamide ribonucleotide formyltransferase (GARFTase) structures, and published X-ray crystal structures of 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/inosine monophosphate cyclohydrolase (ATIC), SHMT1, and folate receptor (FR) α and ß afforded 11 analogues. Multitargeted inhibition and selective tumor transport were designed by providing promiscuous conformational flexibility in the molecules. Metabolite rescue identified mitochondrial C1 metabolism along with de novo purine biosynthesis as the targeted pathways. We identified analogues with tumor-selective transport via FRs and increased SHMT2, SHMT1, and GARFTase inhibition (28-, 21-, and 11-fold, respectively) compared to 1. These multitargeted agents represent an exciting new structural motif for targeted cancer therapy with substantial advantages of selectivity and potency over clinically used antifolates.
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Antineoplásicos , Antagonistas do Ácido Fólico , Hidroximetil e Formil Transferases , Neoplasias , Humanos , Antineoplásicos/química , Carbono , Citosol , Antagonistas do Ácido Fólico/química , Hidroximetil e Formil Transferases/metabolismo , Mitocôndrias , Neoplasias/metabolismoRESUMO
OBJECTIVES: Cognitive and emotional deficits have been documented in youth with pediatric bipolar disorder (PBD); however, to date, a systematic evaluation of comprehension and memory for verbally presented information has not been conducted. The effect of emotion on comprehension and memory for verbally presented material also has not been examined. We examined whether youth with PBD have difficulty recalling the big picture (macrostructure) as well as the story details (microstructure). METHODS: A total of 35 youth with PBD and 25 healthy controls completed an Affective Story Task. A psychological processing model allowed for the examination of both the macrostructure and microstructure of language comprehension. RESULTS: Youth with PBD were capable of comprehending the gist of the stories and were not impaired by emotion when comprehending and remembering macrostructure. However, negative emotional material was found to proactively interfere with the encoding and recall of microstructure. Level of depression appeared to impact recall of microstructure, but not macrostructure. CONCLUSIONS: Negatively valenced material may impair subsequent comprehension and memory for details among youth with PBD. This deficit could impact the daily functioning of these youth, as the perception of negative affect may derail aspects of successful comprehension and learning.
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Transtorno Bipolar/complicações , Transtornos Cognitivos/etiologia , Compreensão/fisiologia , Transtornos da Memória/etiologia , Rememoração Mental/fisiologia , Adolescente , Análise de Variância , Criança , Transtornos Cognitivos/diagnóstico , Deficiências do Desenvolvimento/etiologia , Emoções , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Aprendizagem VerbalRESUMO
Major self-mutilation, defined as self-inflicted physical harm without suicidal intent, can be a catastrophic complication of schizoaffective disorder. Oedipism and self-amputation are two sequelae seen in schizoaffective patients. Oedipism is a type of self-mutilation where an individual inflicts an ocular injury to oneself, often leading to blindness. Self-amputation, another complication seen in those with schizoaffective disorder, is defined as the act of deliberately removing healthy limbs. This case report discusses a 39-year-old Ukrainian-American male with a history of schizoaffective disorder who displayed both oedipism and self-amputation behavior of varying extremities. The patient's plan of care was established once an extensive history was obtained and medical records were consolidated. This report contributes to the literature on rare cases of oedipism and self-amputation in patients diagnosed with schizoaffective disorder, depressed type.
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Irritable bowel syndrome (IBS) is a widespread chronic functional gastrointestinal (GI) disorder having bidirectional comorbidity with psychiatric disorders. This review focuses on psychological treatment of IBS, focusing on symptom severity rather than IBS diagnostic criteria. We chose this dimensional approach in order to assess mind-body effects as an alternative or complement to conventional medical treatment, which focuses on symptom relief. We calculated the effect sizes for various psychosocial-mind-body therapies (MBTs) for IBS symptoms in both children and adults. Therapies included meditation, relaxation, yoga, autogenic training, progressive relaxation, general training in stress coping, hypnotherapy, biofeedback, psycho-education, psychodynamic psychotherapy, and cognitive behavioral therapy. We performed a meta-regression analyses and mixed effects contrasts to find various outcome differences, and we analyzed their relative efficacy in both children and adults. We found 53 studies in 50 reports describing randomized controlled trials. Medium to high effect sizes were found across all methods compared with various controls, with possibly higher effects for children. We found no systematic differences among treatment methods. Meta-regression analyses showed no significant effect for the presence of psychophysiological training, meditation or explicit exposure procedures as treatment components, although most MBTs include exposure as a nonexplicit treatment characteristic, and many relaxation techniques have meditative characteristics. We conclude that there is considerable evidence that an array of mind-body and other psychological therapies can be effective complements to medical treatment for IBS symptom severity, with little evidence for relative superiority of any particular approach. We suggest that the various methods may operate through different mechanisms.
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Síndrome do Intestino Irritável/terapia , Terapias Mente-Corpo , Fatores Etários , Treinamento Autógeno , Biorretroalimentação Psicológica , Terapia Cognitivo-Comportamental , Humanos , Hipnose , Síndrome do Intestino Irritável/fisiopatologia , Síndrome do Intestino Irritável/psicologia , Meditação , Atenção Plena , Educação de Pacientes como Assunto , Intervenção Psicossocial , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , YogaRESUMO
Folate-dependent one-carbon (C1) metabolism is compartmentalized into the mitochondria and cytosol and supports cell growth through nucleotide and amino acid biosynthesis. Mitochondrial C1 metabolism, including serine hydroxymethyltransferase (SHMT) 2, provides glycine, NAD(P)H, ATP, and C1 units for cytosolic biosynthetic reactions, and is implicated in the oncogenic phenotype across a wide range of cancers. Whereas multitargeted inhibitors of cytosolic C1 metabolism, such as pemetrexed, are used clinically, there are currently no anticancer drugs that specifically target mitochondrial C1 metabolism. We used molecular modeling to design novel small-molecule pyrrolo[3,2-d]pyrimidine inhibitors targeting mitochondrial C1 metabolism at SHMT2. In vitro antitumor efficacy was established with the lead compounds (AGF291, AGF320, AGF347) toward lung, colon, and pancreatic cancer cells. Intracellular targets were identified by metabolic rescue with glycine and nucleosides, and by targeted metabolomics using a stable isotope tracer, with confirmation by in vitro assays with purified enzymes. In addition to targeting SHMT2, inhibition of the cytosolic purine biosynthetic enzymes, ß-glycinamide ribonucleotide formyltransferase and/or 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase, and SHMT1 was also established. AGF347 generated significant in vivo antitumor efficacy with potential for complete responses against both early-stage and upstage MIA PaCa-2 pancreatic tumor xenografts, providing compelling proof-of-concept for therapeutic targeting of SHMT2 and cytosolic C1 enzymes by this series. Our results establish structure-activity relationships and identify exciting new drug prototypes for further development as multitargeted antitumor agents.
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Antineoplásicos/farmacologia , Carbono/metabolismo , Citosol/metabolismo , Mitocôndrias/metabolismo , Pirimidinas/farmacologia , Pirróis/farmacologia , Animais , Antineoplásicos/química , Vias Biossintéticas/efeitos dos fármacos , Células CHO , Linhagem Celular Tumoral , Cricetinae , Cricetulus , Citosol/efeitos dos fármacos , Feminino , Concentração Inibidora 50 , Metabolômica , Camundongos SCID , Mitocôndrias/efeitos dos fármacos , Purinas/biossíntese , Pirimidinas/química , Pirróis/química , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
All clinically used antifolates lack transport selectivity for tumors over normal cells resulting in dose-limiting toxicities. There is growing interest in developing novel tumor-targeted cytotoxic antifolates with selective transport into tumors over normal cells via the proton-coupled folate transporter (PCFT) over the ubiquitously expressed reduced folate carrier (RFC). A lack of X-ray crystal structures or predictive models for PCFT or RFC has hindered structure-aided drug design for PCFT-selective therapeutics. Four-point validated models (pharmacophores) were generated for PCFT/Activity (HBA, NI, RA, RA) and RFC/Activity (HBD, NI, HBA, HBA) based on inhibition (IC50) of proliferation of isogenic Chinese hamster ovary (CHO) cells engineered to express only human PCFT or only RFC. Our results revealed substantial differences in structural features required for transport of novel molecules by these transporters which can be utilized for developing transporter-selective antifolates.
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Desenvolvimento de Medicamentos , Antagonistas do Ácido Fólico/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Transportador de Folato Acoplado a Próton/química , Proteína Carregadora de Folato Reduzido/química , Animais , Células CHO , Cricetulus , Antagonistas do Ácido Fólico/farmacologia , Humanos , Concentração Inibidora 50 , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos TestesRESUMO
The first dual-degree program combining both the doctor of pharmacy (PharmD) and the doctor of medicine (MD) degrees was designed and launched by Rutgers, The State University of New Jersey, in academic year 2013-2014. This joint effort was led by the Ernest Mario School of Pharmacy (EMSOP) and the Robert Wood Johnson Medical School (RWJMS) to combine expertise in both diagnostic and treatment facets of health care and to prepare graduates for leadership roles in providing and managing comprehensive patient care in a variety of settings. One area of potential value of these skill sets is the drug development industry. A survey was conducted among pharmaceutical executive stakeholders associated with a postdoctoral training program to assess the perceived value of this new dual-degree skill set and to identify particular functions where the combined training has its best fit. Results indicate that the combined nature of this training is highly valued in this setting, especially in the areas of clinical pharmacology, drug safety and pharmacovigilance, medical affairs/strategy, and medical science liaisons. Future monitoring of graduates will further define the value of this dual degree in this and other health care settings.
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OBJECTIVES: The objective of this narrative review was to examine the usage of ketamine as a postoperative analgesic agent across a wide variety of surgeries. DESIGN: A literature search was performed using the phrases "ketamine" and "postoperative pain." The authors analyzed the studies that involved testing ketamine's effectiveness at controlling postoperative pain. Effectiveness was assessed through various outcomes such as the amount of opiate consumption, visual analog scale (VAS) pain scores, and persistent postoperative pain at long-term follow-up. RESULTS: While many different administration protocols were evaluated, delivering ketamine both as a pre- or perioperative bolus and postoperative infusion for up to 48 hours appeared to be the most effective. These effects are dose-dependent. However, a number of studies analyzed showed no benefit in using ketamine versus placebo for controlling postoperative pain. While ketamine is a safe and well-tolerated drug, it does have adverse effects, and there are concerns for possible neurotoxicity and effects on memory. CONCLUSIONS: In a number of limited situations, ketamine has shown some efficacy in controlling postoperative pain and decreasing opioid consumption. More randomized controlled trials are necessary to determine the surgical procedures and administrations (i.e., intravenous, epidural) that ketamine is best suited for.