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1.
Int J Mol Sci ; 25(13)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39000244

RESUMO

Cutaneous wounds, both acute and chronic, begin with loss of the integrity, and thus barrier function, of the skin. Surgery and trauma produce acute wounds. There are 22 million surgical procedures per year in the United States alone, based on data from the American College of Surgeons, resulting in a prevalence of 6.67%. Acute traumatic wounds requiring repair total 8 million per year, 2.42% or 24.2 per 1000. The cost of wound care is increasing; it approached USD 100 billion for just Medicare in 2018. This burden for wound care will continue to rise with population aging, the increase in metabolic syndrome, and more elective surgeries. To heal a wound, an orchestrated, evolutionarily conserved, and complex series of events involving cellular and molecular agents at the local and systemic levels are necessary. The principal factors of this important function include elements from the neurological, cardiovascular, immune, nutritional, and endocrine systems. The objectives of this review are to provide clinicians engaged in wound care and basic science researchers interested in wound healing with an updated synopsis from recent publications. We also present data from our primary investigations, testing the hypothesis that cannabidiol can alter cutaneous wound healing and documenting their effects in wild type (C57/BL6) and db/db mice (Type 2 Diabetes Mellitus, T2DM). The focus is on the potential roles of the endocannabinoid system, cannabidiol, and the important immune-regulatory wound cytokine IL-33, a member of the IL-1 family, and connective tissue growth factor, CTGF, due to their roles in both normal and abnormal wound healing. We found an initial delay in the rate of wound closure in B6 mice with CBD, but this difference disappeared with time. CBD decreased IL-33 + cells in B6 by 70% while nearly increasing CTGF + cells in db/db mice by two folds from 18.6% to 38.8% (p < 0.05) using a dorsal wound model. We review the current literature on normal and abnormal wound healing, and document effects of CBD in B6 and db/db dorsal cutaneous wounds. CBD may have some beneficial effects in diabetic wounds. We applied 6-mm circular punch to create standard size full-thickness dorsal wounds in B6 and db/db mice. The experimental group received CBD while the control group got only vehicle. The outcome measures were rate of wound closure, wound cells expressing IL-33 and CTGF, and ILC profiles. In B6, the initial rate of wound closure was slower but there was no delay in the time to final closure, and cells expressing IL-33 was significantly reduced. CTGF + cells were higher in db/bd wounds treated with CBD. These data support the potential use of CBD to improve diabetic cutaneous wound healing.


Assuntos
Canabidiol , Pele , Cicatrização , Cicatrização/efeitos dos fármacos , Animais , Canabidiol/farmacologia , Canabidiol/uso terapêutico , Humanos , Pele/metabolismo , Pele/efeitos dos fármacos , Camundongos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico
2.
Water Res ; 256: 121620, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677036

RESUMO

Phage emit communication signals that inform their lytic and lysogenic life cycles. However, little is known regarding the abundance and diversity of the genes associated with phage communication systems in wastewater treatment microbial communities. This study focused on phage communities within two distinct biochemical wastewater environments, specifically aerobic membrane bioreactors (AeMBRs) and anaerobic membrane bioreactors (AnMBRs) exposed to varying antibiotic concentrations. Metagenomic data from the bench-scale systems were analyzed to explore phage phylogeny, life cycles, and genetic capacity for antimicrobial resistance and quorum sensing. Two dominant phage families, Schitoviridae and Peduoviridae, exhibited redox-dependent dynamics. Schitoviridae prevailed in anaerobic conditions, while Peduoviridae dominated in aerobic conditions. Notably, the abundance of lytic and lysogenic proteins varied across conditions, suggesting the coexistence of both life cycles. Furthermore, the presence of antibiotic resistance genes (ARGs) within viral contigs highlighted the potential for phage to transfer ARGs in AeMBRs. Finally, quorum sensing genes in the virome of AeMBRs indicated possible molecular signaling between phage and bacteria. Overall, this study provides insights into the dynamics of viral communities across varied redox conditions in MBRs. These findings shed light on phage life cycles, and auxiliary genetic capacity such as antibiotic resistance and bacterial quorum sensing within wastewater treatment microbial communities.


Assuntos
Bacteriófagos , Reatores Biológicos , Filogenia , Bacteriófagos/genética , Anaerobiose , Percepção de Quorum , Resistência Microbiana a Medicamentos/genética , Águas Residuárias , Aerobiose
4.
Bioanalysis ; 14(19): 1257-1270, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36416749

RESUMO

Aim: To develop and validate a bioanalytical method for the quantification of INCB000928 in hemodialysate. Materials & methods: Blank dialysate and phosphate-buffered saline were compared with hemodialysate for surrogate matrix selection. Direct addition of internal standard without analyte extraction and a high-performance LC-MS/MS were used for analysis. Results & conclusion: INCB000928 in hemodialysate exhibited strong nonspecific binding to polypropylene containers. In the presence of 10% isopropyl alcohol, the loss of INCB000928 was fully recovered, regardless of pre- or post-addition of the solvent. Blank dialysate and phosphate-buffered saline were determined to be appropriate surrogate matrices by using a three-way cross-comparison and were subsequently validated in the quantitative analysis of INCB000928 in hemodialysate.


Fibrodysplasia ossificans progressiva (FOP) is a very rare disease characterized by congenital malformation of the great toes and progressive heterotopic ossification. The genetic cause of FOP is mutation in the gene ALK2. INCB000928 is a novel and orally available drug that inhibits ALK2 protein activity and has been shown to prevent ossification in a laboratory mouse model of FOP. Patients with end-stage renal disease who undergo hemodialysis may require a different dose of INCB000928. This study showed that INCB000928 was heavily adsorbed by the container wall, resulting in underestimated drug levels in hemodialysate. We present a method to accurately measure INCB000928 levels in hemodialysate by using isopropyl alcohol as an antiadsorption agent and cost-effective surrogate matrix.


Assuntos
Miosite Ossificante , Humanos , Soluções para Hemodiálise , Cromatografia Líquida , Receptores de Ativinas Tipo I/metabolismo , Espectrometria de Massas em Tandem , Inibidores de Proteínas Quinases , Fosfatos
5.
Bioanalysis ; 14(7): 405-419, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35264018

RESUMO

Aim: To develop a bioanalytical method for quantifying INCB000928 in human saliva. Materials & methods: Human centrifuged saliva and human whole saliva were compared for matrix selection. Protein precipitation extraction and HPLC-MS/MS was used for analysis. Results & conclusion: Nonspecific binding of INCB000928 was reduced in whole versus centrifuged saliva. Whole saliva was a preferred matrix for INCB000928 bioanalytical method validation. Incurred sample reanalysis (ISR) using a successfully validated method failed in a healthy volunteer study because of inhomogeneous INCB000928 concentration across sample tube depths. Individual mixing of sample tubes followed by immediate aliquoting corrected the ISR failure, with 97.2% of repeats passing versus 41.7% for the same ISR samples.


Fibrodysplasia ossificans progressiva (FOP) is a very rare condition where bone forms outside the skeleton (ossification), leading to restricted movement, decreased quality of life and shortened life span. Mutations in a gene called ALK2 have been identified as causing FOP. INCB000928 is a novel drug (to be taken by mouth) which inhibits ALK2 activity and prevents ossification in a laboratory mouse model of FOP. Because monitoring of the levels and efficacy of a drug often requires blood draws, which can be taxing in patients with FOP, this study aimed to develop a method to measure INCB000928 levels in saliva. The authors propose a unique procedure to process saliva samples to ensure accurate, reproducible quantitation of INCB000928 levels in saliva.


Assuntos
Miosite Ossificante , Saliva , Receptores de Ativinas Tipo I/genética , Receptores de Ativinas Tipo I/metabolismo , Humanos , Mutação , Saliva/metabolismo , Espectrometria de Massas em Tandem
6.
Br J Clin Pharmacol ; 88(1): 237-247, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34169560

RESUMO

AIMS: Pemigatinib, an inhibitor of the fibroblast growth factor receptor (FGFR) family of receptor tyrosine kinases, is approved for previously treated, unresectable locally advanced or metastatic cholangiocarcinoma. Pemigatinib is predominantly metabolized by CYP3A4 with minimal renal elimination. METHODS: Separate hepatic and renal impairment studies were conducted to evaluate the effect of these impairments on pemigatinib pharmacokinetics (PK). Each study was of open-label, parallel-group design, conducted in participants with normal organ function and with hepatic or renal impairment. Plasma concentrations of pemigatinib were quantified by liquid chromatography tandem mass spectrometry (LC-MS/MS) and pemigatinib PK parameters were derived by noncompartmental analysis. Geometric mean ratios and two-sided 90% confidence intervals of Cmax , AUC0-t , and AUC0-∞ were compared by analysis of variance (ANOVA). RESULTS: Compared with healthy matched participants: Cmax and AUC0-∞ ratio (90% confidence interval) in participants with moderate hepatic impairment were 96.7% (59.4%, 157%) and 146% (100%, 212%), respectively; Cmax and AUC0-∞ ratio in participants with severe hepatic impairment were 94.2% (68.9%, 129%) and 174% (116%, 261%), respectively; Cmax and AUC0-∞ ratio in participants with severe renal impairment were 64.6% (44.1%, 94.4%) and 159% (95.4%, 264%), respectively; Cmax and AUC0-∞ ratio in participants with end-stage renal disease (ESRD) before haemodialysis (HD) were 77.5% (51.2%, 118%) and 76.8% (54.0%, 109%), respectively; Cmax and AUC0-∞ ratio in participants with ESRD after HD were 90.0% (59.3%, 137%) and 91.3% (64.1%, 130%), respectively. CONCLUSION: Pemigatinib dose should be reduced for patients with severe hepatic or renal impairment, and no dose adjustment is required for patients with moderate hepatic impairment or in ESRD patients undergoing HD.


Assuntos
Falência Renal Crônica , Hepatopatias , Insuficiência Renal , Área Sob a Curva , Cromatografia Líquida , Humanos , Rim/metabolismo , Falência Renal Crônica/terapia , Morfolinas , Pirimidinas , Pirróis , Espectrometria de Massas em Tandem
8.
Eur J Clin Pharmacol ; 77(12): 1887-1897, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34282472

RESUMO

PURPOSE: Pemigatinib (INCB054828), a potent and selective oral fibroblast growth factor receptor 1-3 inhibitor, is a Biopharmaceutical Classification System class II compound with good permeability and pH-dependent solubility that is predominantly metabolized by cytochrome P450 (CYP) 3A. Two drug-drug interaction studies, one with acid-reducing agents, esomeprazole (proton pump inhibitor [PPI]) and ranitidine (histamine-2 [H2] antagonist), and the other with potent CYP3A-modulating agents, itraconazole (CYP3A inhibitor) and rifampin (CYP3A inducer), were performed. METHODS: Both were open-label, fixed-sequence studies conducted in up to 36 healthy participants each, enrolled into two cohorts (n = 18 each). Pemigatinib plasma concentration was measured, and pharmacokinetic parameters were derived by non-compartmental analysis. RESULTS: There was an 88% and 17% increase in pemigatinib area under the plasma drug concentration-time curve (AUC) and maximum plasma drug concentration (Cmax), respectively, with itraconazole, and an 85% and 62% decrease in pemigatinib AUC and Cmax with rifampin coadministration. There was a 35% and 8% decrease in pemigatinib AUC and Cmax, respectively, with esomeprazole, and a 2% decrease in Cmax and 3% increase in AUC with ranitidine coadministration. In both studies, all adverse events reported were grade ≤ 2. CONCLUSION: Coadministration with itraconazole or rifampin resulted in a clinically significant change in pemigatinib exposure. Therefore, coadministration of strong CYP3A inducers with pemigatinib should be avoided, and the dose of pemigatinib should be reduced if coadministration with strong CYP3A inhibitors cannot be avoided. The effect of PPIs/H2 antagonists on pemigatinib exposure was modest, and pemigatinib can be administered without regard to coadministration of PPIs/H2 antagonists.


Assuntos
Antiulcerosos/farmacologia , Indutores do Citocromo P-450 CYP3A/farmacologia , Inibidores do Citocromo P-450 CYP3A/farmacologia , Morfolinas/farmacocinética , Pirimidinas/farmacocinética , Pirróis/farmacocinética , Área Sob a Curva , Citocromo P-450 CYP3A/metabolismo , Interações Medicamentosas , Voluntários Saudáveis , Humanos , Taxa de Depuração Metabólica , Morfolinas/efeitos adversos , Morfolinas/sangue , Pirimidinas/efeitos adversos , Pirimidinas/sangue , Pirróis/efeitos adversos , Pirróis/sangue
9.
Environ Res ; 200: 111456, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34111440

RESUMO

Although extensive research to date has focused on enhancing removal rates of antibiotics from municipal wastewaters, the transformation products formed by anaerobic treatment processes remain understudied. The present work aims to examine the possible roles that the different microbial communities of an anaerobic membrane bioreactor (AnMBR) play in the transformation of antibiotics during wastewater treatment. As part of this work, sulfamethoxazole, erythromycin, and ampicillin were added in separate stages to the influent of the AnMBR at incremental concentrations of 10, 50, and 250 µg/L each. Antibiotic-specific transformation products detected during each stage, as identified by high resolution LC-MS, are reported herein. Results suggest that both isoxazole (sulfamethoxazole) and ß-lactam (ampicillin) ring opening could be facilitated by the AnMBR's bioprocess. Microbial community analysis results indicated that relative activity of the system's suspended biomass consistently shifted towards syntrophic groups throughout the duration of the experiment. Notable differences were also observed between the suspended biomass and the AnMBR's membrane biofilms. Membrane-attached biofilm communities showed high relative activities of several specific methanogenic (Methanothrix and Methanomethylovorans), syntrophic (Syntrophaceae), and sulfate-reducing (Desulfomonile) groups. Such groups have been previously identified as involved in the formation of the antibiotic degradation products observed in the effluent of the AnMBR. The activity of these communities within the biofilms likely confers certain advantages that aid in the biotransformation of the antibiotics tested.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Anaerobiose , Antibacterianos , Biofilmes , Reatores Biológicos , Águas Residuárias
10.
Front Bioeng Biotechnol ; 9: 613626, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912543

RESUMO

Co-digestion of fats, oils, and grease (FOG) with food waste (FW) can improve the energy recovery in anaerobic membrane bioreactors (AnMBRs). Here, we investigated the effect of co-digestion of FW and FOG in AnMBRs at fat mass loading of 0.5, 0.75, and 1.0 kg m-3 day-1 with a constant organic loading rate of 5.0 gCOD L-1 day-1 in both a single-phase (SP) and two-phase (TP) configuration. A separate mono-digestion of FW at an identical organic loading rate was used as the benchmark. During co-digestion, higher daily biogas production, ranging from 4.0 to 12.0%, was observed in the two-phase methane phase (TP-MP) reactor compared to the SP reactor, but the difference was statistically insignificant (p > 0.05) due to the high variability in daily biogas production. However, the co-digestion of FW with FOG at 1.0 kg m-3 day-1 fat loading rate significantly (p < 0.05) improved daily biogas production in both the SP (11.0%) and TP (13.0%) reactors compared to the mono-digestion of FW. Microbial community analyses using cDNA-based MinION sequencing of weekly biomass samples from the AnMBRs revealed the prevalence of Lactobacillus (92.2-95.7% relative activity) and Anaerolineaceae (13.3-57.5% relative activity), which are known as fermenters and fatty acid degraders. Syntrophic fatty acid oxidizers were mostly present in the SP and TP-MP reactors, possibly because of the low pH and short solid retention time (SRT) in the acid phase digesters. A greater abundance of the mcrA gene copies (and methanogens) was observed in the SP and MP reactors compared to the acid-phase (AP) reactors. This study demonstrates that FW and FOG can be effectively co-digested in AnMBRs and is expected to inform full-scale decisions on the optimum fat loading rate.

11.
Environ Sci Technol ; 54(19): 12742-12751, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32875793

RESUMO

Anaerobic membrane bioreactors (AnMBRs) can significantly reduce the release of antibiotic resistance elements to the environment. The purpose of this study was to elucidate the role of membrane fouling layers (biofilms) in mitigating the release of intracellular and extracellular antibiotic resistance genes (iARGs and eARGs) from an AnMBR. The AnMBR was equipped with three membrane modules, each exhibiting a different level of fouling. Results showed that the absolute abundance of ARGs decreased gradually in the suspended biomass during operation of the AnMBR. Normalized abundances of targeted ARGs and intI1 were found to be significantly higher in the fouling layers compared to the suspended biomass, implying adsorption or an increased potential for horizontal gene transfer of ARGs in the biofilm. Effluent ARG data revealed that the highly fouled (HF) membrane significantly reduced the absolute abundance of eARGs. However, the HF membrane effluent concomitantly had the highest absolute abundance of iARGs. Nevertheless, total ARG abundance (sum of iARG and eARG) in the effluent of the AnMBR was not impacted by the extent of fouling. These results suggest a need for a combination of different treatment technologies to effectively prevent antibiotic resistance proliferation associated with these two ARG fractions.


Assuntos
Antibacterianos , Águas Residuárias , Anaerobiose , Antibacterianos/farmacologia , Reatores Biológicos , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Membranas Artificiais
12.
J Clin Pharmacol ; 59(12): 1641-1647, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31282592

RESUMO

Itacitinib is a potent, selective JAK-1 inhibitor currently in phase 3 development for the treatment of acute and chronic graft-versus-host disease (GVHD) in combination with corticosteroids. Itacitinib is primarily eliminated via metabolism by cytochrome P-450 (CYP)3A4 with minimal renal elimination. A drug-drug interaction study was conducted to evaluate the impact of the strong CYP3A inhibitor itraconazole or the strong CYP3A4 inducer rifampin on the pharmacokinetics of itacitinib in healthy volunteers. In cohort 1, subjects received 200 mg sustained release (SR) tablets of itacitinib on days 1 and 6 and 200 mg itraconazole on days 2-7. In cohort 2, subjects received 200 mg SR itacitinib on days 1 and 9 and 600 mg rifampin on days 2-9. Thirty-six subjects were enrolled, 18 in each cohort with 17 completing itacitinib dosing in cohort 1 and 15 completing itacitinib dosing in cohort 2. Coadministration of itraconazole with itacitinib resulted in a nearly 5-fold increase in area under the concentration-time curve (AUC0-∞ ) (geometric mean ratio [GMR] 4.88, 90%Cl 4.17-5.72) and an ∼3-fold increase in peak concentration (Cmax ) (GMR 3.15, 90%Cl 2.58-3.54). Coadministration of rifampin with itacitinib resulted in a nearly 80% decrease in AUC0-∞ (GMR 0.208, 90%Cl 0.173, 0.249) and Cmax (GMR 0.231, 90%Cl 0.195, 0.274). Results of this study informed the study design of the phase 3 GVHD protocols with regard to coadministration of strong CYP3A inhibitors and CYP3A4 inducers. These data combined with phase 3 data will inform final dosing recommendations.


Assuntos
Itraconazol/uso terapêutico , Inibidores de Proteínas Quinases/farmacocinética , Rifampina/uso terapêutico , Administração Oral , Adulto , Área Sob a Curva , Citocromo P-450 CYP3A/metabolismo , Indutores do Citocromo P-450 CYP3A/uso terapêutico , Inibidores do Citocromo P-450 CYP3A/uso terapêutico , Interações Medicamentosas/fisiologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
Environ Sci Technol ; 53(7): 3599-3609, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30810034

RESUMO

Anaerobic membrane bioreactors (AnMBRs) are an emerging technology with potential to improve energy efficiency and effluent reuse in mainstream wastewater treatment. However, their contribution to the proliferation of contaminants of emerging concern, such as antibiotic resistance genes (ARGs), remains largely unknown. The purpose of this study was to determine the effect of select influent antibiotics at varying concentrations on the presence and abundance of ARGs in an AnMBR system and its effluent. Quantification of targeted ARGs revealed distinct profiles in biomass and effluent, with genes conferring resistance to different antibiotic classes dominating in biomass (macrolides) and effluent (sulfonamides). Effluent sul1 gene abundance was strongly correlated with abundance of intl1, signifying the potential importance of mobile genetic elements in ARG release from AnMBR systems. The addition of specific antibiotics also affected normalized abundances of their related ARGs, exemplifying the potential impact of selective pressures at both low (10 µg/L) and high (250 µg/L) influent antibiotic concentrations.


Assuntos
Antibacterianos , Eliminação de Resíduos Líquidos , Anaerobiose , Reatores Biológicos , Resistência Microbiana a Medicamentos , Genes Bacterianos , Águas Residuárias
14.
Nanotechnology ; 27(37): 375202, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27486701

RESUMO

Advances in semiconductor technology due to the aggressive downward scaling of on-chip feature sizes have led to rapid rises in the resistivity and current density of interconnect conductors. As a result, current interconnect materials, Cu and W, are subject to performance and reliability constraints approaching or exceeding their physical limits. Therefore, alternative materials are being actively considered as potential replacements to meet such constraints. The carbon nanotube (CNT) is among the leading replacement candidates for on-chip interconnect vias due to its high aspect-ratio nanostructure and superior current-carrying capacity to Cu and W, as well as other potential candidates. Based on the results for 40 nm and 60 nm top-contact metallized CNT vias, we demonstrate that not only are their current-carrying capacities two orders of magnitude higher than their Cu and W counterparts, they are enhanced by reduced via resistance due to contact engineering facilitated by the first reported contact resistance extraction scheme for a 40 nm linewidth.

15.
Artigo em Inglês | MEDLINE | ID: mdl-25337387

RESUMO

BACKGROUND: After the failure of so many drugs and therapies for acute ischemic stroke, innovative approaches are needed to develop new treatments. One promising strategy is to test combinations of agents in the pre-hospital setting prior to the administration of intravenous tissue plasminogen activator (IV-tPA) and/ or the use of mechanical reperfusion devices in the hospital. METHODS: We performed a 2 × 2 factorial design preclinical trial where we tested minocycline (MINO), remote ischemic perconditioning (RIPerC) and their combination treatment in a thromboembolic clot model of stroke in mice, without IV-tPA or later treated with IV-tPA at 4 hours post-stroke. Cerebral blood flow (CBF) was measured by laser speckle contrast imaging (LSCI), behavioral outcomes as neurological deficit score (NDS) and adhesive tape removal test, and infarct size measurement were performed at 48 hours post-stroke. Mice within the experimental sets were randomized for the different treatments, and all outcome measures were blinded. RESULTS: RIPerC significantly improved CBF as measured by LSCI in both with and without tPA treated mice (P < 0.001). MINO and RIPerC treatment were effective alone at reducing infarct size (p < 0.0001) and improving short-term functional outcomes (p < 0.001) in the tPA and non-tPA treated animals. The combination treatment of MINO and RIPerC significantly reduced the infarct size greater than either intervention alone (p < 0.05). There were trends in favor of improving functional outcomes after combination treatment of MINO and RIPerC; however combination treatment group was not significantly different than the individual treatments of MINO and RIPerC. There was no "statistical" interaction between minocycline and RIPerC treatments indicating that the effects of RIPerC and MINO were additive and not synergistic on the outcome measures. CONCLUSION: In the future, combining these two safe and low cost interventions in the ambulance has the potential to "freeze" the penumbra and improve outcomes in stroke patients. This pre-clinical 2 × 2 design can be easily translated into a pre-hospital clinical trial.

16.
Nanotechnology ; 25(37): 375702, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25148299

RESUMO

Ion-beam-induced deposition (IBID) and electron-beam-induced deposition (EBID) with tungsten (W) are evaluated for engineering electrical contacts with carbon nanofibers (CNFs). While a different tungsten-containing precursor gas is utilized for each technique, the resulting tungsten deposits result in significant contact resistance reduction. The performance of CNF devices with W contacts is examined and conduction across these contacts is analyzed. IBID-W, while yielding lower contact resistance than EBID-W, can be problematic in the presence of on-chip semiconducting devices, whereas EBID-W provides substantial contact resistance reduction that can be further improved by current stressing. Significant differences between IBID-W and EBID-W are observed at the electrode contact interfaces using high-resolution transmission electron microscopy. These differences are consistent with the observed electrical behaviors of their respective test devices.

17.
Bioanalysis ; 5(15): 1831-41, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23905857

RESUMO

This White Paper is focused on the technical aspects regarding quantifying pharmaceutically derived inorganic elements in biomatrices in support of GLP nonclinical and clinical studies using inductively coupled plasma (ICP) techniques. For decades ICP has been used in support of Environmental Protection Agency analyses and has more recently been applied for use in the pharmaceutical industry. Current bioanalytical method validation and sample analysis regulatory guidance applies to chromatographic platforms used for analysis of large- and small-molecule PK and TK assessments; however, it is not directly applicable to all aspects of various ICP techniques. Increasingly, quadrupole and high-resolution ICP-MS methods of analysis are being used to quantify inorganic elements contained in pharmaceutical compounds and biomatrices. Many elements occur endogenously in biomatrices, affecting quantification of blanks, standard curve samples, QC samples, and the selection of appropriate levels for the LLOQ.


Assuntos
Descoberta de Drogas/instrumentação , Descoberta de Drogas/métodos , Preparações Farmacêuticas/análise , Espectrofotometria Atômica/instrumentação , Espectrofotometria Atômica/métodos , Biomarcadores/análise , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Biomarcadores/urina , Calibragem , Descoberta de Drogas/normas , Elementos Químicos , Guias como Assunto , Limite de Detecção , Preparações Farmacêuticas/sangue , Preparações Farmacêuticas/líquido cefalorraquidiano , Preparações Farmacêuticas/urina , Controle de Qualidade , Padrões de Referência , Manejo de Espécimes , Espectrofotometria Atômica/normas , Estudos de Validação como Assunto
18.
Sci China Life Sci ; 56(9): 767-79, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23900568

RESUMO

The BRAIN project recently announced by the president Obama is the reflection of unrelenting human quest for cracking the brain code, the patterns of neuronal activity that define who we are and what we are. While the Brain Activity Mapping proposal has rightly emphasized on the need to develop new technologies for measuring every spike from every neuron, it might be helpful to consider both the theoretical and experimental aspects that would accelerate our search for the organizing principles of the brain code. Here we share several insights and lessons from the similar proposal, namely, Brain Decoding Project that we initiated since 2007. We provide a specific example in our initial mapping of real-time memory traces from one part of the memory circuit, namely, the CA1 region of the mouse hippocampus. We show how innovative behavioral tasks and appropriate mathematical analyses of large datasets can play equally, if not more, important roles in uncovering the specific-to-general feature-coding cell assembly mechanism by which episodic memory, semantic knowledge, and imagination are generated and organized. Our own experiences suggest that the bottleneck of the Brain Project is not only at merely developing additional new technologies, but also the lack of efficient avenues to disseminate cutting edge platforms and decoding expertise to neuroscience community. Therefore, we propose that in order to harness unique insights and extensive knowledge from various investigators working in diverse neuroscience subfields, ranging from perception and emotion to memory and social behaviors, the BRAIN project should create a set of International and National Brain Decoding Centers at which cutting-edge recording technologies and expertise on analyzing large datasets analyses can be made readily available to the entire community of neuroscientists who can apply and schedule to perform cutting-edge research.


Assuntos
Mapeamento Encefálico , Região CA1 Hipocampal/fisiologia , Memória , Animais , Humanos , Camundongos
19.
Neurobiol Learn Mem ; 105: 200-10, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23838072

RESUMO

It has been widely recognized that the understanding of the brain code would require large-scale recording and decoding of brain activity patterns. In 2007 with support from Georgia Research Alliance, we have launched the Brain Decoding Project Initiative with the basic idea which is now similarly advocated by BRAIN project or Brain Activity Map proposal. As the planning of the BRAIN project is currently underway, we share our insights and lessons from our efforts in mapping real-time episodic memory traces in the hippocampus of freely behaving mice. We show that appropriate large-scale statistical methods are essential to decipher and measure real-time memory traces and neural dynamics. We also provide an example of how the carefully designed, sometime thinking-outside-the-box, behavioral paradigms can be highly instrumental to the unraveling of memory-coding cell assembly organizing principle in the hippocampus. Our observations to date have led us to conclude that the specific-to-general categorical and combinatorial feature-coding cell assembly mechanism represents an emergent property for enabling the neural networks to generate and organize not only episodic memory, but also semantic knowledge and imagination.


Assuntos
Mapeamento Encefálico , Hipocampo/fisiologia , Memória Episódica , Semântica , Animais , Medo/fisiologia , Humanos , Camundongos , Rede Nervosa/fisiologia , Neurônios/fisiologia
20.
Drugs R D ; 13(2): 119-28, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23615868

RESUMO

BACKGROUND: In clinical practice, α2-adrenoceptor agonists have been adjunctively administered with psychostimulants for the treatment of attention-deficit/hyperactivity disorder (ADHD). Two studies have examined the adjunctive use of guanfacine extended release (GXR, Intuniv®; Shire Development LLC, Wayne, PA, USA) with psychostimulants in children and adolescents with a suboptimal response to psychostimulant treatment. However, the potential for pharmacokinetic drug-drug interactions (DDIs) between GXR and lisdexamfetamine dimesylate (LDX, Vyvanse®; Shire US LLC, Wayne, PA, USA) has not been thoroughly evaluated. OBJECTIVE: The primary objective of this study was to examine the pharmacokinetics of GXR 4 mg and LDX 50 mg given as single doses alone and in combination. STUDY DESIGN: This was an open-label, randomized, three-period crossover, DDI study. SETTING: The study was conducted in a single clinical research center. PARTICIPANTS: Forty-two healthy adults were randomized in this study. INTERVENTIONS: Subjects were administered single oral doses of GXR 4 mg, LDX 50 mg, or GXR and LDX in combination. MAIN OUTCOME MEASURES: Blood samples collected predose and up to 72 h postdose assessed guanfacine, LDX, and d-amphetamine levels. Bioequivalence was defined as the 90% confidence intervals (CIs) of the geometric mean ratios of the area under the plasma concentration-time curve extrapolated to infinity (AUC0-∞) and maximum plasma concentration (Cmax) falling within the bioequivalence reference interval (0.80-1.25). Safety measures included adverse events, vital signs, and electrocardiograms (ECGs). RESULTS: Forty subjects completed the study. Following administration of LDX alone or in combination with GXR, the statistical comparisons of the AUC0-∞ and Cmax of d-amphetamine fell entirely within the reference interval. For guanfacine, the 90% CI of the geometric mean ratio of AUC∞ for the two treatments was within the bioequivalence criteria, but for Cmax the upper bound of the 90% CI exceeded the standard range for bioequivalence by 7%. This relatively small change is unlikely to be clinically meaningful. Treatment-emergent adverse events (TEAEs) were reported by 42.9% of subjects; the most commonly reported TEAEs included dizziness (5.0, 7.3, and 7.3%) and headache (7.5, 4.9, and 7.3%) following administration of GXR, LDX, and GXR and LDX in combination, respectively. Clinically significant ECG abnormalities occurred in one subject following administration of LDX and in one subject following coadministration of GXR and LDX. CONCLUSIONS: In healthy adults, coadministration of GXR and LDX did not result in a clinically meaningful pharmacokinetic DDI compared with either treatment alone. No unique TEAEs were observed with coadministration of GXR and LDX compared with either treatment alone.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacocinética , Estimulantes do Sistema Nervoso Central/farmacocinética , Dextroanfetamina/farmacocinética , Guanfacina/farmacocinética , Adolescente , Agonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Agonistas de Receptores Adrenérgicos alfa 2/efeitos adversos , Adulto , Estimulantes do Sistema Nervoso Central/administração & dosagem , Estimulantes do Sistema Nervoso Central/efeitos adversos , Dextroanfetamina/administração & dosagem , Dextroanfetamina/efeitos adversos , Interações Medicamentosas , Quimioterapia Combinada/efeitos adversos , Eletrocardiografia/efeitos dos fármacos , Feminino , Guanfacina/administração & dosagem , Guanfacina/efeitos adversos , Humanos , Dimesilato de Lisdexanfetamina , Masculino , Pessoa de Meia-Idade , Equivalência Terapêutica , Sinais Vitais/efeitos dos fármacos
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