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1.
Toxicol Pathol ; : 1926233241245108, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38661116

RESUMO

The European Society of Toxicologic Pathology (ESTP) organized a panel of 24 international experts from many fields of toxicologic clinical pathology (e.g., industry, academia, and regulatory) that came together in 2021 to align the use of terminology to convey the importance of clinical pathology findings in preclinical toxicity studies. An additional goal consisted of how to identify important findings in standard and nonstandard clinical pathology associated endpoints. This manuscript summarizes the information and opinions discussed and shared at the ninth ESTP International Expert Workshop, April 5 to 6, 2022. In addition to terminology usage, the workshop considered topics related to the identification and conveyance of the importance of test item-related findings. These topics included sources of variability, comparators, statistics, reporting, correlations to other study data, nonstandard biomarkers, indirect/secondary findings, and an overall weight-of-evidence approach.

2.
Aust Crit Care ; 2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38797584

RESUMO

BACKGROUND: Following critical illness, family members are often required to adopt caregiving responsibilities. Anxiety and depression are common long term problems for both patients and caregivers. However, at present, it is not known how the trajectories of these symptoms compare between patients and caregivers. OBJECTIVES: The aim of this study was to investigate and compare the trajectories of anxiety and depression in patients and caregivers in the first year following critical illness. METHODS: This study analyses data from a prospective multicentre cohort study of patients and caregivers who underwent a complex recovery intervention following critical illness. Paired patients and caregivers were recruited. The Hospital Anxiety and Depression Scale was used to evaluate symptoms of anxiety and depression at three timepoints: baseline; 3 months; and 12 months in both patient and caregivers. A linear mixed-effects regression model was used to evaluate the trajectories of these symptoms over the first year following critical illness. RESULTS: 115 paired patients and caregivers, who received the complex recovery intervention, were recruited. There was no significant difference in the relative trajectory of depressive symptoms between patients and caregivers in the first 12 months following critical illness (p = 0.08). There was, however, a significant difference in the trajectory of anxiety symptoms between patients and caregivers during this time period (p = 0.04), with caregivers seeing reduced resolution of symptoms in comparison to patients. CONCLUSIONS: Following critical illness, symptoms of anxiety and depression are common in both patients and caregivers. The trajectory of symptoms of depression was similar between caregivers and patients; however, there was a significantly different recovery trajectory in symptoms of anxiety. Further research is required to understand the recovery pathway of caregivers in order to design effective interventions.

3.
Angew Chem Int Ed Engl ; 63(2): e202314423, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37984884

RESUMO

A general and straightforward procedure for the lithiation trapping of cyclic sulfides such as tetrahydrothiophene, tetrahydrothiopyran and a thiomorpholine is described. Trapping with a wide range of electrophiles is demonstrated, leading to more than 50 diverse α-substituted saturated sulfur heterocycles. The methodology provides access to a range of α-substituted cyclic sulfides that are not easily synthesised by the currently available methods.

4.
Lancet ; 400(10350): 431-440, 2022 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-35934006

RESUMO

BACKGROUND: Whole breast irradiation (WBI) after conservative surgery for ductal carcinoma in situ (DCIS) reduces local recurrence. We investigated whether a tumour bed boost after WBI improved outcomes, and examined radiation dose fractionation sensitivity for non-low-risk DCIS. METHODS: The study was an international, randomised, unmasked, phase 3 trial involving 136 participating centres of six clinical trials organisations in 11 countries (Australia, New Zealand, Singapore, Canada, the Netherlands, Belgium, France, Switzerland, Italy, Ireland, and the UK). Eligible patients were women aged 18 years or older with unilateral, histologically proven, non-low-risk DCIS treated by breast-conserving surgery with at least 1 mm of clear radial resection margins. They were assigned to one of four groups (1:1:1:1) of no tumour bed boost versus boost after conventional versus hypofractionated WBI, or randomly assigned to one of two groups (1:1) of no boost versus boost after each centre prespecified conventional or hypofractionated WBI. The conventional WBI used was 50 Gy in 25 fractions, and hypofractionated WBI was 42·5 Gy in 16 fractions. A boost dose of 16 Gy in eight fractions, if allocated, was delivered after WBI. Patients and clinicians were not masked to treatment allocation. The primary endpoint was time to local recurrence. This trial is registered with ClinicalTrials.gov (NCT00470236). FINDINGS: Between June 25, 2007, and June 30, 2014, 1608 patients were randomly assigned to have no boost (805 patients) or boost (803 patients). Conventional WBI was given to 831 patients, and hypofractionated WBI was given to 777 patients. Median follow-up was 6·6 years. The 5-year free-from-local-recurrence rates were 92·7% (95% CI 90·6-94·4%) in the no-boost group and 97·1% (95·6-98·1%) in the boost group (hazard ratio 0·47; 0·31-0·72; p<0·001). The boost group had higher rates of grade 2 or higher breast pain (10% [8-12%] vs 14% [12-17%], p=0·003) and induration (6% [5-8%] vs 14% [11-16%], p<0·001). INTERPRETATION: In patients with resected non-low-risk DCIS, a tumour bed boost after WBI reduced local recurrence with an increase in grade 2 or greater toxicity. The results provide the first randomised trial data to support the use of boost radiation after postoperative WBI in these patients to improve local control. The international scale of the study supports the generalisability of the results. FUNDING: National Health and Medical Research Council of Australia, Susan G Komen for the Cure, Breast Cancer Now, OncoSuisse, Dutch Cancer Society, Canadian Cancer Trials Group.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Neoplasias da Mama/etiologia , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Canadá , Carcinoma Intraductal não Infiltrante/radioterapia , Carcinoma Intraductal não Infiltrante/cirurgia , Fracionamento da Dose de Radiação , Feminino , Humanos , Masculino , Mastectomia Segmentar , Recidiva Local de Neoplasia/etiologia , Estadiamento de Neoplasias , Doses de Radiação
5.
Thorax ; 78(2): 160-168, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35314485

RESUMO

RATIONALE: At present, clinicians aiming to support patients through the challenges after critical care have limited evidence to base interventions. OBJECTIVES: Evaluate a multicentre integrated health and social care intervention for critical care survivors. A process evaluation assessed factors influencing the programme implementation. METHODS: This study evaluated the impact of the Intensive Care Syndrome: Promoting Independence and Return to Employment (InS:PIRE) programme. We compared patients who attended this programme with a usual care cohort from the same time period across nine hospital sites in Scotland. The primary outcome was health-related quality of life (HRQoL) measured via the EuroQol 5-dimension 5-level instrument, at 12 months post hospital discharge. Secondary outcome measures included self-efficacy, depression, anxiety and pain. RESULTS: 137 patients who received the InS:PIRE intervention completed outcome measures at 12 months. In the usual care cohort, 115 patients completed the measures. The two cohorts had similar baseline demographics. After adjustment, there was a significant absolute increase in HRQoL in the intervention cohort in relation to the usual care cohort (0.12, 95% CI 0.04 to 0.20, p=0.01). Patients in the InS:PIRE cohort also reported self-efficacy scores that were 7.7% higher (2.32 points higher, 95% CI 0.32 to 4.31, p=0.02), fewer symptoms of depression (OR 0.38, 95% CI 0.19 to 0.76, p=0.01) and similar symptoms of anxiety (OR 0.58, 95% CI 0.30 to 1.13, p=0.11). There was no significant difference in overall pain experience. Key facilitators for implementation were: integration with inpatient care, organisational engagement, flexibility to service inclusion; key barriers were: funding, staff availability and venue availability. CONCLUSIONS: This multicentre evaluation of a health and social care programme designed for survivors of critical illness appears to show benefit at 12 months following hospital discharge.


Assuntos
Estado Terminal , Qualidade de Vida , Humanos , Estado Terminal/terapia , Cuidados Críticos , Hospitalização , Alta do Paciente , Análise Custo-Benefício
6.
Biochem J ; 477(22): 4383-4395, 2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33111951

RESUMO

A fragment screen of a library of 560 commercially available fragments using a kinetic assay identified a small molecule that increased the activity of the fungal glycoside hydrolase TrBgl2. An analogue by catalogue approach and detailed kinetic analysis identified improved compounds that behaved as nonessential activators with up to a 2-fold increase in maximum activation. The compounds did not activate the related bacterial glycoside hydrolase CcBglA demonstrating specificity. Interestingly, an analogue of the initial fragment inhibits both TrBgl2 and CcBglA, apparently through a mixed-model mechanism. Although it was not possible to determine crystal structures of activator binding to 55 kDa TrBgl2, solution NMR experiments demonstrated a specific binding site for the activator. A partial assignment of the NMR spectrum gave the identity of the amino acids at this site, allowing a model for TrBgl2 activation to be built. The activator binds at the entrance of the substrate-binding site, generating a productive conformation for the enzyme-substrate complex.


Assuntos
Ativadores de Enzimas/química , Proteínas Fúngicas/química , Hypocreales/química , beta-Glucosidase/química , Ressonância Magnética Nuclear Biomolecular
7.
Chemistry ; 26(41): 8969-8975, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32315100

RESUMO

Fragment-based drug discovery is now widely adopted for lead generation in the pharmaceutical industry. However, fragment screening collections are often predominantly populated with flat, 2D molecules. Herein, we describe a workflow for the design and synthesis of 56 3D disubstituted pyrrolidine and piperidine fragments that occupy under-represented areas of fragment space (as demonstrated by a principal moments of inertia (PMI) analysis). A key, and unique, underpinning design feature of this fragment collection is that assessment of fragment shape and conformational diversity (by considering conformations up to 1.5 kcal mol-1 above the energy of the global minimum energy conformer) is carried out prior to synthesis and is also used to select targets for synthesis. The 3D fragments were designed to contain suitable synthetic handles for future fragment elaboration. Finally, by comparing our 3D fragments with six commercial libraries, it is clear that our collection has high three-dimensionality and shape diversity.

8.
Drug Discov Today Technol ; 38: 77-90, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34895643

RESUMO

Fragment-based drug discovery (FBDD) has grown into a well-established approach in the pursuit of new therapeutics. Key to the success of FBDD is the low molecular complexity of the initial hits and this has resulted in fragment libraries that mainly contain compounds with a two-dimensional (2D) shape. In an effort to increase the chemical diversity and explore the impact of increased molecular complexity on the hit rate of fragment library screening, several academic and industrial groups have designed and synthesised novel fragments with a three-dimensional (3D) shape. This review provides an overview of 25 synthetic 3D fragment libraries from the recent literature. We calculate and compare physicochemical properties and descriptors that are typically used to measure molecular three-dimensionality such as fraction sp3 (Fsp3), plane of best fit (PBF) scores and principal moment of inertia (PMI) plots. Although the libraries vary widely in structure and properties, some key common features can be identified which may have utility in designing the next generation of 3D fragment libraries.


Assuntos
Descoberta de Drogas , Bibliotecas de Moléculas Pequenas
9.
Circulation ; 137(4): 376-387, 2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29138292

RESUMO

BACKGROUND: Regional variations in reperfusion times and mortality in patients with ST-segment-elevation myocardial infarction are influenced by differences in coordinating care between emergency medical services (EMS) and hospitals. Building on the Accelerator-1 Project, we hypothesized that time to reperfusion could be further reduced with enhanced regional efforts. METHODS: Between April 2015 and March 2017, we worked with 12 metropolitan regions across the United States with 132 percutaneous coronary intervention-capable hospitals and 946 EMS agencies. Data were collected in the ACTION (Acute Coronary Treatment and Intervention Outcomes Network)-Get With The Guidelines Registry for quarterly Mission: Lifeline reports. The primary end point was the change in the proportion of EMS-transported patients with first medical contact to device time ≤90 minutes from baseline to final quarter. We also compared treatment times and mortality with patients treated in hospitals not participating in the project during the corresponding time period. RESULTS: During the study period, 10 730 patients were transported to percutaneous coronary intervention-capable hospitals, including 974 in the baseline quarter and 972 in the final quarter who met inclusion criteria. Median age was 61 years; 27% were women, 6% had cardiac arrest, and 6% had shock on admission; 10% were black, 12% were Latino, and 10% were uninsured. By the end of the intervention, all process measures reflecting coordination between EMS and hospitals had improved, including the proportion of patients with a first medical contact to device time of ≤90 minutes (67%-74%; P<0.002), a first medical contact to device time to catheterization laboratory activation of ≤20 minutes (38%-56%; P<0.0001), and emergency department dwell time of ≤20 minutes (33%-43%; P<0.0001). Of the 12 regions, 9 regions reduced first medical contact to device time, and 8 met or exceeded the national goal of 75% of patients treated in ≤90 minutes. Improvements in treatment times corresponded with a significant reduction in mortality (in-hospital death, 4.4%-2.3%; P=0.001) that was not apparent in hospitals not participating in the project during the same time period. CONCLUSIONS: Organization of care among EMS and hospitals in 12 regions was associated with significant reductions in time to reperfusion in patients with ST-segment-elevation myocardial infarction as well as in in-hospital mortality. These findings support a more intensive regional approach to emergency care for patients with ST-segment-elevation myocardial infarction.


Assuntos
Serviço Hospitalar de Cardiologia/organização & administração , Prestação Integrada de Cuidados de Saúde/organização & administração , Serviço Hospitalar de Emergência/organização & administração , Disparidades em Assistência à Saúde , Avaliação de Resultados em Cuidados de Saúde/organização & administração , Intervenção Coronária Percutânea , Regionalização da Saúde/organização & administração , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Tempo para o Tratamento/organização & administração , Transporte de Pacientes/organização & administração , Idoso , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Avaliação de Programas e Projetos de Saúde , Sistema de Registros , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/mortalidade , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
10.
Opt Express ; 27(13): 18892-18899, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31252824

RESUMO

We demonstrate a 6.5 mW single transverse and polarization mode GaAs-based oxide-confined VCSEL at 850 nm. High power is enabled by a relatively large oxide aperture and an epitaxial design for low resistance, low optical loss, and high slope efficiency VCSELs. With the oxide aperture supporting multiple polarization unrestrained transverse modes, single transverse and polarization mode operation is achieved by a transverse and polarization mode filter etched into the surface of the VCSEL. While the VCSEL is specifically designed for light source integration on a silicon photonic integrated circuit, its performance in terms of power, spectral purity, polarization, and beam properties are of great interest for a large range of applications.

11.
Acta Orthop ; 90(1): 21-25, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30712497

RESUMO

Background and purpose - Most often, the goal of non-geriatric femoral neck fracture surgery is to preserve the native hip joint. However, reoperations for painful implants, osteonecrosis, and nonunion are common. We determined the reoperation rate and time-to-reoperation following internal fixation of these fractures in a large population cohort. Patients and methods - This retrospective cohort study included patients between the ages of 18 and 50 years old who underwent internal fixation for a femoral neck fracture during 1997-2013. Patients were followed until December 2013. Primary outcomes were reoperation rate and time-to-reoperation. Time-to-event analysis was performed to estimate the rate of any reoperation and for THA specifically, while testing the dependency of time-to-reoperation on secondary variables. Results - 796 young femoral neck fracture patients were treated with internal fixation during the study period (median age 43 years, 39% women). Median follow-up was 8 years (IQR 4-13). One-third underwent at least 1 reoperation at a median 16 months after the index surgery (IQR 8-31). Half of reoperations were for implant removal, followed by conversion to total hip arthroplasty. 14% of the cohort were converted to THA. The median time to conversion was 2 years (IQR 1-4). Neither female sex nor older age had a statistically significant effect on time-to-reoperation or time-to-THA conversion. Interpretation - Following internal fixation of young femoral neck fracture, 1 in 3 patients required a reoperation, and 1 in 7 were converted to THA. These data should be considered by patients and surgeons during treatment decision-making.


Assuntos
Artroplastia de Quadril , Fixação Interna de Fraturas/efeitos adversos , Complicações Pós-Operatórias/cirurgia , Adulto , Fatores Etários , Artroplastia de Quadril/métodos , Artroplastia de Quadril/estatística & dados numéricos , Colúmbia Britânica/epidemiologia , Estudos de Coortes , Bases de Dados Factuais/estatística & dados numéricos , Feminino , Fraturas do Colo Femoral/epidemiologia , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Complicações Pós-Operatórias/classificação , Reoperação/métodos , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
12.
Opt Express ; 26(3): 3638-3645, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29401891

RESUMO

This paper describes an integrated six-beam homodyne laser Doppler vibrometry (LDV) system based on a silicon-on-insulator (SOI) full platform technology, with on-chip photo-diodes and phase modulators. Electronics and optics are also implemented around the integrated photonic circuit (PIC) to enable a simultaneous six-beam measurement. Measurement of a propagating guided elastic wave in an aluminum plate (speed ≈ 909 m/s @ 61.5 kHz) is demonstrated.

13.
Drug Chem Toxicol ; 41(1): 51-61, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28298149

RESUMO

Methotrexate (MTX) is a folic acid antagonist that is widely used to treat a variety of diseases. One of the most serious side effects of MTX therapy is hepatotoxicity. The potential molecular cytotoxic mechanisms of MTX toward isolated rat hepatocytes were investigated using Accelerated Cytotoxicity Mechanism Screening (ACMS) techniques. A concentration and time dependent increase in cytotoxicity and reactive oxygen species (ROS) formation and a decrease in mitochondrial membrane potential (MMP) were observed with MTX. Furthermore, a significant increase in MTX (300 µM)-induced cytotoxicity and ROS formation were observed when glutathione (GSH)-depleted hepatocytes were used whereas addition of N-acetylcysteine (a GSH precursor) decreased cytotoxicity. Catalase inactivation also increased MTX-induced cytotoxicity, while the direct addition of catalase to the hepatocytes decreased cytotoxicity. MTX treatment in isolated rat mitochondria caused swelling and significantly decreased adenosine triphosphate (ATP) and GSH content, and cytochrome c release. Potent antioxidants such as mesna, resveratrol and Trolox decreased MTX-induced cytotoxicity and ROS formation and increased MMP. This study suggests that MTX-induced cytotoxicity caused by ROS formation and GSH oxidation leads to oxidative stress and mitochondrial injury in rat hepatocytes.


Assuntos
Citocromos c/metabolismo , Antagonistas do Ácido Fólico/toxicidade , Hepatócitos/efeitos dos fármacos , Metotrexato/toxicidade , Mitocôndrias Hepáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Antioxidantes/farmacologia , Catalase/metabolismo , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Hepatócitos/enzimologia , Hepatócitos/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/enzimologia , Mitocôndrias Hepáticas/patologia , Dilatação Mitocondrial/efeitos dos fármacos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo
14.
J Environ Manage ; 206: 826-835, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29197808

RESUMO

Contaminated soils pose a risk to human and ecological health, and thermal remediation is an efficient and reliable way to reduce soil contaminant concentration in a range of situations. A primary benefit of thermal treatment is the speed at which remediation can occur, allowing the return of treated soils to a desired land use as quickly as possible. However, this treatment also alters many soil properties that affect the capacity of the soil to function. While extensive research addresses contaminant reduction, the range and magnitude of effects to soil properties have not been explored. Understanding the effects of thermal remediation on soil properties is vital to successful reclamation, as drastic effects may preclude certain post-treatment land uses. This review highlights thermal remediation studies that have quantified alterations to soil properties, and it supplements that information with laboratory heating studies to further elucidate the effects of thermal treatment of soil. Notably, both heating temperature and heating time affect i) soil organic matter; ii) soil texture and mineralogy; iii) soil pH; iv) plant available nutrients and heavy metals; v) soil biological communities; and iv) the ability of the soil to sustain vegetation. Broadly, increasing either temperature or time results in greater contaminant reduction efficiency, but it also causes more severe impacts to soil characteristics. Thus, project managers must balance the need for contaminant reduction with the deterioration of soil function for each specific remediation project.


Assuntos
Metais Pesados , Poluentes do Solo , Recuperação e Remediação Ambiental , Humanos , Concentração de Íons de Hidrogênio , Solo
15.
Angew Chem Int Ed Engl ; 57(1): 223-226, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29155468

RESUMO

An 8-step, gram-scale synthesis of the (-)-sparteine surrogate (22 % yield, with just 3 chromatographic purifications) and a 10-step, gram-scale synthesis of (-)-sparteine (31 % yield) are reported. Both syntheses proceed with complete diastereocontrol and allow access to either antipode. Since the syntheses do not rely on natural product extraction, our work addresses long-term supply issues relating to these widely used chiral ligands.

16.
Opt Express ; 25(4): 4312-4325, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28241635

RESUMO

We demonstrate how to optimize the performance of PAM-4 transmitters based on lumped Silicon Photonic Mach-Zehnder Modulators (MZMs) for short-reach optical links. Firstly, we analyze the trade-off that occurs between extinction ratio and modulation loss when driving an MZM with a voltage swing less than the MZM's Vπ. This is important when driver circuits are realized in deep submicron CMOS process nodes. Next, a driving scheme based upon a switched capacitor approach is proposed to maximize the achievable bandwidth of the combined lumped MZM and CMOS driver chip. This scheme allows the use of lumped MZM for high speed optical links with reduced RF driver power consumption compared to the conventional approach of driving MZMs (with transmission line based electrodes) with a power amplifier. This is critical for upcoming short-reach link standards such as 400Gb/s 802.3 Ethernet. The driver chip was fabricated using a 65nm CMOS technology and flip-chipped on top of the Silicon Photonic chip (fabricated using IMEC's ISIPP25G technology) that contains the MZM. Open eyes with 4dB extinction ratio for a 36Gb/s (18Gbaud) PAM-4 signal are experimentally demonstrated. The electronic driver chip has a core area of only 0.11mm2 and consumes 236mW from 1.2V and 2.4V supply voltages. This corresponds to an energy efficiency of 6.55pJ/bit including Gray encoder and retiming, or 5.37pJ/bit for the driver circuit only.

17.
Chem Res Toxicol ; 30(3): 804-829, 2017 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-28147486

RESUMO

A multiparametric, live-cell, high-content-screening (HCS) cytotoxicity assay was first demonstrated in 2006 ( Arch. Toxicol. 2006 , 80 , 580 - 604 ) to be highly concordant with human hepatotoxicity, including idiosyncratic hepatotoxicities and other target organ toxicities in contrast to historical assays. The success of the assay was attributed to its simultaneous measurement of multiple appropriate "cytobiomarkers": use of human cells with xenometabolic competence for toxicities mediated by metabolites, 72 h exposure to enable expression of slower-acting toxicants, exposure to a wide-range of concentrations from 30- to 100-fold the efficacious concentration, and normalizing the in vitro cytotoxic concentration to an estimate of the in vivo concentration of exposure. An overwhelming volume of evidence has accumulated over the last 10 years to support this approach as necessary in predictive toxicology. Equivalent assays have now been successfully applied in ∼50 studies across a wide variety of toxicants, toxicities, cell types, and disciplines. Review herein of the wider literature on cytotoxicity since the first assay was reported 100 years ago supports the selection of key cytobiomarkers along a final common pathway of cell injury, including cell proliferation, mitochondrial activity, apoptosis, lysosomal mass, oxidative stress, and cell membrane permeability. HCS studies without inclusion of such key cytobiomarkers or without testing to sufficiently high concentration have not been as successful. Furthermore, a subset of the original toxicants has been reanalyzed herein using the original HCS assay and has confirmed their high sensitivities and specificities across locations, HCS technologies, staff, laboratories, and time. A protocol is demonstrated for operational validation of the assay within laboratories to demonstrate proficiency and quality management.


Assuntos
Sobrevivência Celular/efeitos dos fármacos , Transferência de Tecnologia , Animais , Humanos
18.
J Org Chem ; 82(13): 7023-7031, 2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28574711

RESUMO

To provide α-substituted piperazines for early stage medicinal chemistry studies, a simple, general synthetic approach is required. Here, we report the development of two general and simple procedures for the racemic lithiation/trapping of N-Boc piperazines. Optimum lithiation times were determined using in situ IR spectroscopy, and the previous complicated and diverse literature procedures were simplified. Subsequent trapping with electrophiles delivered a wide range of α-functionalized N-Boc piperazines. The scope and limitations of the distal N-group were investigated. The selective α- and ß- arylation of N-Boc piperazines via lithiation/Negishi coupling is reported.

19.
World J Surg ; 41(6): 1415-1419, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28097413

RESUMO

BACKGROUND: In low- and middle-income countries, the volume of traumatic injuries requiring orthopaedic intervention routinely exceeds the capacity of available surgical resources. The objective of this study was to identify predictors of surgical care for lower extremity fracture patients at a high-demand, resource-limited public hospital in Uganda. METHODS: Skeletally mature patients admitted with the intention of definitive surgical treatment of an isolated tibia or femur fractures to the national referral hospital in Uganda were recruited to participate in this study. Demographic, socioeconomic, and clinical data were collected through participant interviews at the time of injury and 6 months post-injury. Social capital (use of social networks to gain access to surgery), financial leveraging, and ethnicity were also included as variables in this analysis. A probit estimation model was used to identify independent and interactive predictors of surgical treatment. RESULTS: Of the 64 patients included in the final analysis, the majority of participants were male (83%), with a mean age of 40.6, and were injured in a motor vehicle accident (77%). Due to resource constraints, only 58% of participants received surgical care. The use of social capital and femur fractures were identified as significant predictors of receiving surgical treatment, with social capital emerging as the strongest predictor of access to surgery (p < 0.05). CONCLUSION: Limited infrastructure, trained personnel, and surgical supplies rations access to surgical care. In this environment, participants with advantageous social connections were able to self-advocate for surgery where demand for these services greatly exceeded available resources.


Assuntos
Recursos em Saúde/provisão & distribuição , Acessibilidade aos Serviços de Saúde , Ortopedia/estatística & dados numéricos , Acidentes de Trânsito/estatística & dados numéricos , Adulto , Feminino , Fraturas do Fêmur/cirurgia , Hospitalização , Humanos , Masculino , Procedimentos Ortopédicos/estatística & dados numéricos , Encaminhamento e Consulta , Uganda
20.
J Environ Qual ; 46(4): 897-905, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28783790

RESUMO

Successful remediation of oil-contaminated agricultural land may include the goal of returning the land to prespill levels of agricultural productivity. This productivity may be measured by crop yield, quality, and safety, all of which are influenced by soil characteristics. This research was conducted to determine if these metrics are affected in hard red spring wheat ( L. cultivar Barlow) when grown in soils treated by ex situ thermal desorption (TD) compared with wheat grown in native topsoil (TS). Additionally, TD soils were mixed with TS at various ratios to assess the effectiveness of soil mixing as a procedure for enhancing productivity. In two greenhouse studies, TD soils alone produced similar amounts of grain and biomass as TS, although grain protein in TD soils was 22% (±7%) lower. After mixing TS into TD soils, the mean biomass and grain yield were reduced by up to 60%, but grain protein increased. These trends are likely the result of nutrient availability determined by soil organic matter and nutrient cycling performed by soil microorganisms. Thermal desorption soil had 84% (±2%) lower soil organic carbon than TS, and cumulative respiration was greatly reduced (66 ± 2%). From a food safety perspective, grain from TD soils did not show increased uptake of polycyclic aromatic hydrocarbons. Overall, this research suggests that TD soils are capable of producing safe, high-quality grain yields.


Assuntos
Agricultura , Triticum/crescimento & desenvolvimento , Carbono , Solo , Poluentes do Solo/química
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