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1.
Nature ; 610(7933): 731-736, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36261517

RESUMO

Anaerobic methane oxidation exerts a key control on greenhouse gas emissions1, yet factors that modulate the activity of microorganisms performing this function remain poorly understood. Here we discovered extraordinarily large, diverse DNA sequences that primarily encode hypothetical proteins through studying groundwater, sediments and wetland soil where methane production and oxidation occur. Four curated, complete genomes are linear, up to approximately 1 Mb in length and share genome organization, including replichore structure, long inverted terminal repeats and genome-wide unique perfect tandem direct repeats that are intergenic or generate amino acid repeats. We infer that these are highly divergent archaeal extrachromosomal elements with a distinct evolutionary origin. Gene sequence similarity, phylogeny and local divergence of sequence composition indicate that many of their genes were assimilated from methane-oxidizing Methanoperedens archaea. We refer to these elements as 'Borgs'. We identified at least 19 different Borg types coexisting with Methanoperedens spp. in four distinct ecosystems. Borgs provide methane-oxidizing Methanoperedens archaea access to genes encoding proteins involved in redox reactions and energy conservation (for example, clusters of multihaem cytochromes and methyl coenzyme M reductase). These data suggest that Borgs might have previously unrecognized roles in the metabolism of this group of archaea, which are known to modulate greenhouse gas emissions, but further studies are now needed to establish their functional relevance.


Assuntos
Methanosarcinales , Aminoácidos/genética , Anaerobiose , Citocromos/genética , Citocromos/metabolismo , Ecossistema , Sedimentos Geológicos , Gases de Efeito Estufa/metabolismo , Metano/metabolismo , Methanosarcinales/classificação , Methanosarcinales/genética , Methanosarcinales/metabolismo , Oxirredução , Filogenia , Solo
2.
Mol Cell Proteomics ; 21(11): 100422, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36198386

RESUMO

Cellular biomolecular complexes including protein-protein, protein-RNA, and protein-DNA interactions regulate and execute most biological functions. In particular in brain, protein-protein interactions (PPIs) mediate or regulate virtually all nerve cell functions, such as neurotransmission, cell-cell communication, neurogenesis, synaptogenesis, and synaptic plasticity. Perturbations of PPIs in specific subsets of neurons and glia are thought to underly a majority of neurobiological disorders. Therefore, understanding biological functions at a cellular level requires a reasonably complete catalog of all physical interactions between proteins. An enzyme-catalyzed method to biotinylate proximal interacting proteins within 10 to 300 nm of each other is being increasingly used to characterize the spatiotemporal features of complex PPIs in brain. Thus, proximity labeling has emerged recently as a powerful tool to identify proteomes in distinct cell types in brain as well as proteomes and PPIs in structures difficult to isolate, such as the synaptic cleft, axonal projections, or astrocyte-neuron junctions. In this review, we summarize recent advances in proximity labeling methods and their application to neurobiology.


Assuntos
Comunicação Celular , Proteoma , Biotinilação , Sinapses , Encéfalo
3.
Prehosp Emerg Care ; : 1-7, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38776259

RESUMO

OBJECTIVES: Telephone instructions are commonly used to improve cardiopulmonary resuscitation (CPR) by lay bystanders. This usually implies an audio but no visual connection between the provider and the emergency medical telecommunicator. We aimed to investigate whether video-guided feedback via a camera drone enhances the quality of CPR. METHODS: We conducted a randomized controlled simulation trial. Lay rescuers performed 8 min of CPR on an objective feedback manikin. Participants were randomized to receive telephone instructions with (intervention group) or without (control group) a drone providing a visual connection with the telecommunicator after a 2-min run-in phase. Performed work (total compression depth minus total lean depth) was the primary outcome. Secondary outcomes were the proportion of effective chest compressions, average compression depth, subjective physical strain measured every 2 min, and dexterity in the nine-hole peg test after the scenario. Outcomes were compared using the t- and Mann Whitney-U tests. A two-sided p-value of <0.05 was considered significant. RESULTS: We included 27 individuals (14 (52%) female, mean age 41 ± 14 years). Performed work was greater in the intervention than in the control group (41.3 ± 7.0 vs. 33.9 ± 10.9 m; absolute difference 7.5, 95% CI 1.4 to 14.8; p = 0.046), with higher average compression depth (49 ± 7 vs. 40 ± 13 mm; p = 0.041), and higher proportions of adequate chest compressions (43 (IQR 14-60) vs. 3 (0-29) %; p = 0.041). We did not find any significant differences regarding the remaining secondary outcomes. CONCLUSION: Video-guided feedback via drones might be a helpful tool to enhance the quality of telephone-assisted CPR in lay bystanders.

4.
Facial Plast Surg ; 40(2): 234-244, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37907286

RESUMO

Hair restoration surgery (HRS) is typically a safe outpatient or office-based procedure when physicians follow high ethical standards and uphold community practice standards. Patients' clinical outcomes are mostly operator dependent, and temporary and permanent complications rarely occur. Follicular unit excision (FUE) donor harvesting, in particular, is a challenging harvesting technique requiring a long learning curve, physical stamina, higher than average hand-eye coordination and manual dexterity. The types of complications associated with FUE are comparable to linear strip excision (LSE). Similar to LSE donor harvesting, FUE complications may occur irrespective if standard precautions are followed by the physician. As in any skin and scalp procedure, injuries and poor cosmetic outcomes occur despite appropriate preoperative precautions and intraoperative technique. In increasing and greater instances, however, FUE complications are observed when the physician fails to follow hair restoration practice standards and routine surgical precautions. Physician induced, or iatrogenic complications occur more often when untrained licensed surgeons perform HRS, and who fail to meet practice standards and best practices. In the last decade, physician-influenced FUE complications, or iatrogenic cause of FUE injuries are increasingly observed which results in poor aesthetic outcomes. Higher than average FUE complication rates occur in cases involving inadequately trained physicians, as well as in cases where improper delegation of the FUE hair transplant procedure is performed by unlicensed and untrained individuals. In this chapter, we described commonly encountered HRS complications, as well as physician influenced, or iatrogenic causes of FUE complications.


Assuntos
Folículo Piloso , Coleta de Tecidos e Órgãos , Humanos , Folículo Piloso/cirurgia , Coleta de Tecidos e Órgãos/efeitos adversos , Estética Dentária , Cabelo , Doença Iatrogênica
5.
J Proteome Res ; 22(7): 2377-2390, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37311105

RESUMO

Substance use disorders are associated with disruptions in sleep and circadian rhythms that persist during abstinence and may contribute to relapse risk. Repeated use of substances such as psychostimulants and opioids may lead to significant alterations in molecular rhythms in the nucleus accumbens (NAc), a brain region central to reward and motivation. Previous studies have identified rhythm alterations in the transcriptome of the NAc and other brain regions following the administration of psychostimulants or opioids. However, little is known about the impact of substance use on the diurnal rhythms of the proteome in the NAc. We used liquid chromatography coupled to tandem mass spectrometry-based quantitative proteomics, along with a data-independent acquisition analysis pipeline, to investigate the effects of cocaine or morphine administration on diurnal rhythms of proteome in the mouse NAc. Overall, our data reveal cocaine and morphine differentially alter diurnal rhythms of the proteome in the NAc, with largely independent differentially expressed proteins dependent on time-of-day. Pathways enriched from cocaine altered protein rhythms were primarily associated with glucocorticoid signaling and metabolism, whereas morphine was associated with neuroinflammation. Collectively, these findings are the first to characterize the diurnal regulation of the NAc proteome and demonstrate a novel relationship between the phase-dependent regulation of protein expression and the differential effects of cocaine and morphine on the NAc proteome. The proteomics data in this study are available via ProteomeXchange with identifier PXD042043.


Assuntos
Cocaína , Camundongos , Animais , Cocaína/farmacologia , Núcleo Accumbens/metabolismo , Morfina/farmacologia , Morfina/metabolismo , Proteoma/genética , Proteoma/metabolismo , Analgésicos Opioides/metabolismo , Analgésicos Opioides/farmacologia
6.
J Infect Dis ; 226(10): 1823-1833, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-35856671

RESUMO

BACKGROUND: Persistent immune activation is thought to contribute to heightened atherosclerotic cardiovascular disease (ASCVD) risk among people with human immunodeficiency virus (PWH). METHODS: Participants (≥18 years) with or without human immunodeficiency virus (HIV) and without history of clinical ASCVD were enrolled. We hypothesized that increased macrophage-specific arterial infiltration would relate to plaque composition and systemic immune activation among PWH. We applied a novel targeted molecular imaging approach (technetium-99m [99mTc]-tilmanocept single photon emission computed tomography [SPECT]/CT) and comprehensive immune phenotyping. RESULTS: Aortic 99mTc-tilmanocept uptake was significantly higher among PWH (n = 20) than participants without HIV (n = 10) with similar 10-year ASCVD risk (P = .02). Among PWH, but not among participants without HIV, noncalcified aortic plaque volume related directly to aortic 99mTc-tilmanocept uptake at different uptake thresholds. An interaction (P = .001) was seen between HIV status and noncalcified plaque volume, but not calcified plaque (P = .83). Systemic levels of caspase-1 (P = .004), CD14-CD16+ (nonclassical/patrolling/homing) monocytes (P = .0004) and CD8+ T cells (P = .005) related positively and CD4+/CD8+ T-cell ratio (P = .02) inversely to aortic 99mTc-tilmanocept uptake volume. CONCLUSIONS: Macrophage-specific arterial infiltration was higher among PWH and related to noncalcified aortic plaque volume only among PWH. Key systemic markers of immune activation relating to macrophage-specific arterial infiltration may contribute to heightened ASCVD risk among PWH. CLINICAL TRIALS REGISTRATION: NCT02542371.


Assuntos
Aterosclerose , Infecções por HIV , Placa Aterosclerótica , Humanos , Placa Aterosclerótica/diagnóstico por imagem , Infecções por HIV/tratamento farmacológico , Macrófagos , HIV
7.
Transfusion ; 62(10): 2095-2107, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36062961

RESUMO

BACKGROUND: Stories are powerful in their ability to disseminate information in a meaningful way. We hypothesized that a stem cell donation story library optimized for social media could support the education and recruitment of committed unrelated hematopoietic stem cell donors from needed demographic groups. STUDY DESIGN AND METHODS: We developed Why We Swab, a library of stories on stem cell donation (facebook.com/WhyWeSwab; instagram.com/WhyWeSwab; twitter.com/WhyWeSwab), and evaluated its impact across social and traditional media as well as on eligible potential donors' knowledge and attitudes towards donation. RESULTS: As of December 2021, the library included 28 story arcs featuring 45 storytellers from diverse ancestral backgrounds, including 8 donor-recipient stories. Overall, the stories reached >92,000 people across social media. Notably, stories were republished by 18 print/ broadcast media outlets in Canada and by major medical organizations. A series of stories shown to 33 eligible potential donors improved mean total scores on a donation knowledge test (64% to 85%, p < 0.001), reduced mean ambivalence scale scores (3.85 to 2.70, p < 0.001), and improved participants' willingness to register as donors (45% to 73%, p < 0.005). Data are also shown demonstrating that stakeholders valued the library and that its deployment was associated with improved donor recruitment outcomes in Canada. CONCLUSION: Why We Swab is accessible and relevant to a wide audience, including stem cell donor registries and recruitment organizations seeking to improve their recruitment efforts as well as to blood and organ & tissue donation organizations who can adapt the Why We Swab model to their audiences.


Assuntos
Transplante de Órgãos , Mídias Sociais , Obtenção de Tecidos e Órgãos , Células-Tronco Hematopoéticas , Humanos , Doadores de Tecidos
8.
Vox Sang ; 117(4): 587-596, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34725827

RESUMO

Background and Objectives Communities of practice (CoPs) represent effective models to achieve quality outcomes in health care. We report the development and evaluation of a CoP to improve stem cell donor recruitment in Canada. Materials and Methods In September 2017, we invited national stakeholders in stem cell donor recruitment to participate in a Facebook group and regular e-meetings. E-meetings involved speakers and roundtable discussion on topics related to donor recruitment. The Facebook group facilitated sharing of resources. We evaluated stakeholder perspective of the CoP and the impact on recruitment outcomes. Results As of December 2020, the CoP included 382 members who published 243 posts to the Facebook group about patient/donor stories (40%), resources (27%), updates/questions (21%) and recruitment outcomes (12%). In January 2020, we surveyed 44 CoP participants; the majority felt that the Facebook group (86%) and e-meetings (59%) supported the community, and that the CoP fostered collaboration (82%), improved their donor recruitment knowledge (75%) and practice (77%) and improved their ability to recruit needed donors (64%). The launch of the CoP correlated with improved donor recruitment outcomes. In 2016-2017, CoP participants recruited 2918 registrants (46% male; 55.9% non-Caucasian) compared to 4531 registrants in 2018-2019 (52.9% male; 62.7% non-Caucasian). Members of the CoP developed innovative resources to support recruitment efforts and led national campaigns securing coverage in major media outlets. Conclusion We describe the first CoP in stem cell donor recruitment to be formally evaluated. The CoP model may be adopted by donor recruitment organisations, registries and blood banks worldwide to improve recruitment outcomes. HIGHLIGHTS: • A community of practice (CoP) in stem cell donor recruitment was valued by participants and supported efforts to improve recruitment outcomes. • The CoP model may be adopted by donor recruitment organizations, donor registries, and blood banks worldwide to improve recruitment outcomes.


Assuntos
Bancos de Sangue , Doadores de Tecidos , Feminino , Humanos , Masculino , Sistema de Registros , Células-Tronco , Inquéritos e Questionários
9.
Br J Clin Pharmacol ; 88(12): 5359-5368, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35849446

RESUMO

AIMS: To investigate and characterise the pharmacokinetics of febuxostat and the effect of the covariates of renal function and body size descriptors on the pharmacokinetics of the drug. METHODS: Blood samples (n = 239) were collected using sparse and rich sampling strategies from healthy (n = 9) and gouty (n = 29) subjects. Febuxostat plasma concentrations were measured by a validated high-performance liquid chromatography method. Population pharmacokinetic analysis was performed using NONMEM. A common variability on bioavailability (FVAR) approach was used to test the effect of fed status on absorption parameters. Covariates were modelled using a power model. RESULTS: The time course of the plasma concentrations of febuxostat is best described by a two-compartment model. In the final model, the population mean for apparent clearance (CL/F), apparent central volume of distribution (Vc/F), apparent peripheral volume of distribution (Vp/F), absorption rate constant (ka) and apparent intercompartmental clearance (Q/F) were 6.91 l h-1 , 32.8 l, 19.4 l, 3.6 h-1 and 1.25 l h-1 , respectively. The population parmater variability (coefficient of variation) for CL/F, Vc/F and Vp/F were 13.6, 22 and 19.5%, respectively. Food reduced the relative biovailability and ka by 67% and 87%, respectively. Renal function, as assessed by creatinine clearance, was a significant covariate for CL/F while body mass index was a significant covariate for Vc/F. CONCLUSIONS: Renal function and body mass index were significant covariates. Further work is warranted to investigate the clinical relevance of these results, notably as renal impairment and obesity are common occurrences in people with gout.


Assuntos
Febuxostat , Gota , Humanos , Voluntários Saudáveis , Gota/tratamento farmacológico , Disponibilidade Biológica , Modelos Biológicos
10.
Inorg Chem ; 61(15): 5844-5854, 2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35380803

RESUMO

Halogenated inorganic complexes Ax[MHaly] (A = alkali metal or alkaline earth, M = transition or main group metal, x = 1-3, and y = 2-9) are an archetypal class of compounds that provide entry points to large areas of inorganic and physical chemistry. All of the hexahalo complexes adopt an octahedral, Oh, symmetry (or nearly so). Consequently, one of the bending modes is forbidden in both the infrared and Raman spectra. In the solid state, many of the complexes crystallize in the cubic space group Fm3̅m, which preserves the octahedral symmetry. Even for those that are not cubic, the octahedral symmetry of the [MHal6]n- ion is largely retained and, to a good approximation, so are the selection rules. In the present work, we show that by using the additional information provided by neutron vibrational spectroscopy, in combination with conventional optical spectroscopies, we can generate complete and unambiguous assignments for all the modes. Comparison of the experimental and calculated transition energies for the systems where periodic-density functional theory was possible (i.e., those for which the crystal structure is known) shows that the agreement is almost quantitative. We also provide a linear relationship that enables the prediction of the forbidden mode.

11.
Pediatr Emerg Care ; 38(5): 224-227, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35482495

RESUMO

OBJECTIVE: Unintentional injury is the leading cause of death in children older than 1 year and disproportionately affects pediatric patients in low- and middle-income countries.Improved prehospital care capacity has demonstrated the ability to improve care and save lives. Our collaboration developed and implemented a sustainable prehospital emergency pediatrics care course (EPCC) for Service d'Aide Medicale Urgente, the public emergency medical service in Rwanda. METHODS: A 1-day context-specific EPCC was developed based on international best practices and local feedback. Two cohorts were created to participate in the course. The first group, EPCC 1, was made of 22 Service d'Aide Medicale Urgente providers with preexisting knowledge on the topic who participated in the course and received training to lead future sessions. After completion of the EPCC1, this group led the second cohort, EPCC 2, which was composed of 26 healthcare providers from around Rwanda. Each group completed a 50 question assessment before and after the course. RESULTS: Emergency pediatrics care course 1 mean scores were 58% vs 98% (pre vs post), EPCC 2 mean scores were 49% vs 98% (pre vs post), using matched-pair analysis of 22 and 32 participants, respectively. When comparing unequal variances across the groups with a 2-tailed paired t test, EPCC 1 and EPCC 2 had a statistically significant mean change in pretest and posttest assessment test scores of 40% compared with 46%, P < 0.0001, with 95% confidence interval. A 1-way analysis of variance mean square analysis for the change in scores showed that regardless of the baseline level of training for each participant, all trainees reached similar postassessment scores (F(1) = 1.45, P = 0.2357). CONCLUSIONS: This study demonstrates effective implementation of a context-appropriate prehospital pediatric training program in Kigali, Rwanda. This program may be effective to support capacity development for prehospital care in Rwanda using a qualified local source of instructors.


Assuntos
Serviços Médicos de Emergência , Criança , Pré-Escolar , Pessoal de Saúde/educação , Humanos , Ruanda
12.
J Neurovirol ; 27(1): 101-115, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33405206

RESUMO

Despite improvements in antiretroviral therapy, human immunodeficiency virus type 1 (HIV-1)-associated neurocognitive disorders (HAND) remain prevalent in subjects undergoing therapy. HAND significantly affects individuals' quality of life, as well as adherence to therapy, and, despite the increasing understanding of neuropathogenesis, no definitive diagnostic or prognostic marker has been identified. We investigated transcriptomic profiles in frontal cortex tissues of Simian immunodeficiency virus (SIV)-infected Rhesus macaques sacrificed at different stages of infection. Gene expression was compared among SIV-infected animals (n = 11), with or without CD8+ lymphocyte depletion, based on detectable (n = 6) or non-detectable (n = 5) presence of the virus in frontal cortex tissues. Significant enrichment in activation of monocyte and macrophage cellular pathways was found in animals with detectable brain infection, independently from CD8+ lymphocyte depletion. In addition, transcripts of four poly (ADP-ribose) polymerases (PARPs) were up-regulated in the frontal cortex, which was confirmed by real-time polymerase chain reaction. Our results shed light on involvement of PARPs in SIV infection of the brain and their role in SIV-associated neurodegenerative processes. Inhibition of PARPs may provide an effective novel therapeutic target for HIV-related neuropathology.


Assuntos
Transtornos Cognitivos/virologia , Lobo Frontal/metabolismo , Lobo Frontal/virologia , Poli(ADP-Ribose) Polimerases/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/metabolismo , Animais , Transtornos Cognitivos/metabolismo , Macaca mulatta , Masculino , Síndrome de Imunodeficiência Adquirida dos Símios/virologia
13.
Br J Clin Pharmacol ; 87(11): 4221-4229, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33769612

RESUMO

AIMS: Despite the availability of international consensus guidelines, vancomycin dosing and therapeutic drug monitoring (TDM) remain suboptimal. This study aimed to assess concordance of vancomycin dosing and TDM with institutional guidelines and to identify factors taken into consideration by clinicians when prescribing vancomycin. METHODS: A retrospective audit of 163 patients receiving vancomycin therapy (≥48 hours) was undertaken. Data collected included patient characteristics, dosing history and plasma vancomycin and creatinine concentrations. Concordance of dosing and TDM with institutional guidelines was evaluated. Semi-structured interviews, including simulated prescribing scenarios, were undertaken with prescribers (n = 17) and transcripts analysed. RESULTS: Plasma vancomycin concentrations (n = 1043) were collected during 179 courses of therapy. Only 24% of courses commenced with a loading dose with 72% lower than recommended. The initial maintenance dose was concordant in 42% of courses with 34% lower than recommended. Only 14% of TDM samples were trough vancomycin concentrations. Dose was not adjusted for 60% (21/35) of subtherapeutic and 43% (18/42) of supratherapeutic trough vancomycin concentrations, respectively. Interview participants reported that patient characteristics (including renal function), vancomycin concentrations, guidelines and expert advice influenced vancomycin prescribing decisions. Despite referring to guidelines when completing simulated prescribing scenarios, only 37% of prescribing decisions aligned with guideline recommendations. CONCLUSION: Poor compliance with institutional vancomycin guidelines was observed, despite prescriber awareness of available guidelines. Multifaceted strategies to support prescriber decision-making are required to improve vancomycin dosing and monitoring.


Assuntos
Antibacterianos , Vancomicina , Antibacterianos/uso terapêutico , Monitoramento de Medicamentos , Humanos , Estudos Retrospectivos
14.
Nature ; 523(7559): 208-11, 2015 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-26083755

RESUMO

A prominent feature of the bacterial domain is a radiation of major lineages that are defined as candidate phyla because they lack isolated representatives. Bacteria from these phyla occur in diverse environments and are thought to mediate carbon and hydrogen cycles. Genomic analyses of a few representatives suggested that metabolic limitations have prevented their cultivation. Here we reconstructed 8 complete and 789 draft genomes from bacteria representing >35 phyla and documented features that consistently distinguish these organisms from other bacteria. We infer that this group, which may comprise >15% of the bacterial domain, has shared evolutionary history, and describe it as the candidate phyla radiation (CPR). All CPR genomes are small and most lack numerous biosynthetic pathways. Owing to divergent 16S ribosomal RNA (rRNA) gene sequences, 50-100% of organisms sampled from specific phyla would evade detection in typical cultivation-independent surveys. CPR organisms often have self-splicing introns and proteins encoded within their rRNA genes, a feature rarely reported in bacteria. Furthermore, they have unusual ribosome compositions. All are missing a ribosomal protein often absent in symbionts, and specific lineages are missing ribosomal proteins and biogenesis factors considered universal in bacteria. This implies different ribosome structures and biogenesis mechanisms, and underlines unusual biology across a large part of the bacterial domain.


Assuntos
Bactérias/genética , Microbiologia Ambiental , Genoma Bacteriano/genética , Filogenia , Íntrons/genética , RNA Ribossômico 16S/genética , Proteínas Ribossômicas/genética
15.
Inflammopharmacology ; 29(5): 1255-1259, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34533655

RESUMO

An appreciation of the contribution of Professor Gary Graham to anti-inflammatory and antirheumatic pharmacology and clinical pharmacology.


Assuntos
Anti-Inflamatórios/farmacologia , Antirreumáticos/farmacologia , Farmacologia Clínica/história , Anti-Inflamatórios/história , Antirreumáticos/história , História do Século XX , História do Século XXI , Humanos
16.
J Antimicrob Chemother ; 75(11): 3293-3302, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32790842

RESUMO

BACKGROUND: Current guidelines for intravenous vancomycin identify drug exposure (as indicated by the AUC) as the best pharmacokinetic (PK) indicator of therapeutic outcome. OBJECTIVES: To assess the accuracy of two Bayesian forecasting programs in estimating vancomycin AUC0-∞ in adults with limited blood concentration sampling. METHODS: The application of seven vancomycin population PK models in two Bayesian forecasting programs was examined in non-obese adults (n = 22) with stable renal function. Patients were intensively sampled following a single (1000 mg or 15 mg/kg) dose. For each patient, AUC was calculated by fitting all vancomycin concentrations to a two-compartment model (defined as AUCTRUE). AUCTRUE was then compared with the Bayesian-estimated AUC0-∞ values using a single vancomycin concentration sampled at various times post-infusion. RESULTS: Optimal sampling times varied across different models. AUCTRUE was generally overestimated at earlier sampling times and underestimated at sampling times after 4 h post-infusion. The models by Goti et al. (Ther Drug Monit 2018. 40: 212-21) and Thomson et al. (J Antimicrob Chemother 2009. 63: 1050-7) had precise and unbiased sampling times (defined as mean imprecision <25% and <38 mg·h/L, with 95% CI for mean bias containing zero) between 1.5 and 6 h and between 0.75 and 2 h post-infusion, respectively. Precise but biased sampling times for Thomson et al. were between 4 and 6 h post-infusion. CONCLUSIONS: When using a single vancomycin concentration for Bayesian estimation of vancomycin drug exposure (AUC), the predictive performance was generally most accurate with sample collection between 1.5 and 6 h after infusion, though optimal sampling times varied across different population PK models.


Assuntos
Preparações Farmacêuticas , Vancomicina , Administração Intravenosa , Adulto , Área Sob a Curva , Teorema de Bayes , Humanos
17.
J Antimicrob Chemother ; 75(7): 1981-1984, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32277819

RESUMO

BACKGROUND: Therapeutic drug monitoring (TDM) is recommended to guide voriconazole therapy. OBJECTIVES: To determine compliance of hospital-based voriconazole dosing and TDM with the Australian national guidelines and evaluate the predictive performance of a one-compartment population pharmacokinetic voriconazole model available in a commercial dose-prediction software package. METHODS: A retrospective audit of voriconazole therapy at an Australian public hospital (1 January to 31 December 2016) was undertaken. Data collected included patient demographics, dosing history and plasma concentrations. Concordance of dosing and TDM with Australian guidelines was assessed. Observed concentrations were compared with those predicted by dose-prediction software. Measures of bias (mean prediction error) and precision (mean squared prediction error) were calculated. RESULTS: Adherence to dosing guidelines for 110 courses of therapy (41% for prophylaxis and 59% for invasive fungal infections) was poor, unless oral formulation guidelines recommended a 200 mg dose, the most commonly prescribed dose (56% of prescriptions). Plasma voriconazole concentrations were obtained for 82% (90/110) of courses [median of 3 (range: 1-27) obtained per course]. A minority (27%) of plasma concentrations were trough concentrations [median concentration: 1.5 mg/L (range: <0.1 to >5.0 mg/L)]. Of trough concentrations, 57% (58/101) were therapeutic, 37% (37/101) were subtherapeutic and 6% (6/101) were supratherapeutic. The dose-prediction software performed well, with acceptable bias and precision of 0.09 mg/L (95% CI -0.08 to 0.27) and 1.32 (mg/L)2 (95% CI 0.96-1.67), respectively. CONCLUSIONS: Voriconazole dosing was suboptimal based on published guidelines and TDM results. Dose-prediction software could enhance TDM-guided therapy.


Assuntos
Antifúngicos , Monitoramento de Medicamentos , Austrália , Hospitais , Humanos , Estudos Retrospectivos , Software , Voriconazol
18.
Bioinformatics ; 35(13): 2313-2314, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30462190

RESUMO

SUMMARY: Large-scale, quantitative proteomics data are being generated at ever increasing rates by high-throughput, mass spectrometry technologies. However, due to the complexity of these large datasets as well as the increasing numbers of post-translational modifications (PTMs) that are being identified, developing effective methods for proteomic visualization has been challenging. ProteomicsBrowser was designed to meet this need for comprehensive data visualization. Using peptide information files exported from mass spectrometry search engines or quantitative tools as input, the peptide sequences are aligned to an internal protein database such as UniProtKB. Each identified peptide ion including those with PTMs is then visualized along the parent protein in the Browser. A unique property of ProteomicsBrowser is the ability to combine overlapping peptides in different ways to focus analysis of sequence coverage, charge state or PTMs. ProteomicsBrowser includes other useful functions, such as a data filtering tool and basic statistical analyses to qualify quantitative data. AVAILABILITY AND IMPLEMENTATION: ProteomicsBrowser is implemented in Java8 and is available at https://medicine.yale.edu/keck/nida/proteomicsbrowser.aspx and https://github.com/peng-gang/ProteomicsBrowser. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Visualização de Dados , Proteômica , Bases de Dados de Proteínas , Espectrometria de Massas , Processamento de Proteína Pós-Traducional , Software
19.
Br J Clin Pharmacol ; 86(12): 2486-2496, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32386239

RESUMO

AIMS: To examine the pharmacokinetic-phamacodynamic (PK-PD) relationships of plasma febuxostat and serum urate and the effect of a single dose of the drug on renal excretion and fractional clearance of urate (FCU). METHODS: Blood and urine samples were collected at baseline and up to 145 hours following administration of febuxostat (80 mg) to healthy subjects (n = 9). Plasma febuxostat and serum and urinary urate and creatinine concentrations were determined. Febuxostat pharmacokinetics were estimated using a two-compartment model with first-order absorption. An Emax PK-PD model was fitted to mean febuxostat and urate concentrations. Urinary urate excretion and FCU were calculated pre- and post-dose. RESULTS: Maximum mean plasma concentration of febuxostat (2.7 mg L-1 ) was observed 1.2 hours after dosage. Febuxostat initial and terminal half-lives were 2.0 ± 1.0 and 14.0 ± 4.7 hours (mean ± SD), respectively. The majority (81%) of the drug was eliminated in the 9 hours after dosing. Serum urate declined slowly achieving mean nadir (0.20 mmol L-1 ) at 24 hours. The IC50 (plasma febuxostat concentration that inhibits urate production by 50%) was 0.11 ± 0.09 mg L-1 (mean ± SD). Urinary urate excretion changed in parallel with serum urate. There was no systematic or significant change in FCU from baseline. CONCLUSION: The PK-PD model could potentially be used to individualise febuxostat treatment and improve clinical outcomes. A single dose of febuxostat does not affect the efficiency of the kidney to excrete urate. Further investigations are required to confirm the present results following multiple dosing with febuxostat.


Assuntos
Febuxostat , Supressores da Gota , Gota , Adulto , Febuxostat/farmacocinética , Feminino , Gota/tratamento farmacológico , Supressores da Gota/farmacocinética , Voluntários Saudáveis , Humanos , Rim , Masculino , Eliminação Renal , Ácido Úrico , Adulto Jovem
20.
Environ Sci Technol ; 54(8): 4984-4994, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32181661

RESUMO

Chemical forms of phosphorus (P) in airborne particulate matter (PM) are poorly known and do not correlate with solubility or extraction measurements commonly used to infer speciation. We used P X-ray absorption near-edge structure (XANES) and 31P nuclear magnetic resonance (NMR) spectroscopies to determine P species in PM collected at four mountain sites (Colorado and California). Organic P species dominated samples from high elevations, with organic P estimated at 65-100% of total P in bulk samples by XANES and 79-88% in extracted fractions (62-84% of total P) by NMR regardless of particle size (≥10 or 1-10 µm). Phosphorus monoester and diester organic species were dominant and present in about equal proportions, with low fractions of inorganic P species. By comparison, PM from low elevation contained mixtures of organic and inorganic P, with organic P estimated at 30-60% of total P. Intercontinental PM transport determined from radiogenic lead (Pb) isotopes varied from 0 to 59% (mean 37%) Asian-sourced Pb at high elevation, whereas stronger regional PM inputs were found at low elevation. Airborne flux of bioavailable P to high-elevation ecosystems may be twice as high as estimated by global models, which will disproportionately affect net primary productivity.


Assuntos
Material Particulado/análise , Fósforo/análise , Colorado , Ecossistema , Tamanho da Partícula
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