RESUMEN

Early cow-calf separation followed by individual housing of calves is standard practice on dairy farms. However, a growing body of evidence suggests that as awareness grows the public will oppose these practices, which could compromise the dairy industry's social license. Despite disagreement among different stakeholders over weighting and evaluations of effects of early separation (e.g., distress response, disease risk), recent systematic reviews indicate that there is little scientific evidence supporting this practice. The acceptability of alternative cow-calf management systems is unknown. We used a mixed methods survey with a convenience sample of 307 Canadians plus a representative sample of 1,487 Americans to investigate perceptions of these systems, examining the effects of providing social or foster cow contact following early separation or not separating cow-calf pairs. Attitudes and perceptions of animal welfare were more positive (on a 7-point scale where 1 is most negative, 7 is most positive, and 4 is a neutral midpoint) toward the system where calves were not separated from the cow (mean ± SE; 5.8 ± 0.07; 5.7 ± 0.07), compared with systems in which the calf was separated and individually housed (3.6 ± 0.07; 3.4 ± 0.07), separated and group housed (3.7 ± 0.07; 3.4 ± 0.07), or separated and kept with a foster cow (3.8 ± 0.07; 3.6 ± 0.07). Participants were consistent in their attitudes toward and perceptions of animal welfare within the system, suggesting that participants took a holistic and value-oriented approach to cow-calf management regarding separation. These results, in combination with many participants' concern for the importance of the mother cow-calf relationship and perceptions that severing of this bond was a breach of standard of care, suggest that there may be low acceptance of any cow-calf management system involving early separation as such systems are unlikely to resonate with underlying values.

Asunto(s)

Bienestar del Animal , Industria Lechera , Animales , Actitud , Canadá , Bovinos , Industria Lechera/métodos , Granjas , Femenino , Humanos

RESUMEN

Cyclin-dependent-kinases (CDKs) are members of the serine/threonine kinase family and are highly regulated by cyclins, a family of regulatory subunits that bind to CDKs. CDK9 represents one of the most studied examples of these transcriptional CDKs. CDK9 forms a heterodimeric complex with its regulatory subunit cyclins T1, T2 and K to form the positive transcription elongation factor b (P-TEFb). This complex regulates transcription via the phosphorylation of RNA polymerase II (RNAPolII) on Ser-2, facilitating promoter clearance and transcription elongation and thus remains an attractive therapeutic target. Herein, we have utilized classical affinity purification chemical proteomics, kinobeads assay, compressed CEllular Thermal Shift Assay (CETSA)-MS and Limited Proteolysis (LiP) to study the selectivity, target engagement and downstream mechanistic insights of a CDK9 tool compound. The above experiments highlight the value of quantitative mass spectrometry approaches to drug discovery, specifically proteome wide target identification and selectivity profiling. The approaches utilized in this study unanimously indicated that the CDK family of kinases are the main target of the compound of interest, with CDK9, showing the highest target affinity with remarkable consistency across approaches. We aim to provide guidance to the scientific community on the available chemical biology/proteomic tools to study advanced lead molecules and to highlight pros and cons of each technology while describing our findings in the context of the CDKs biology.

Asunto(s)

Quinasa 9 Dependiente de la Ciclina/antagonistas & inhibidores , Proteómica , Línea Celular Tumoral , Fraccionamiento Químico , Quinasa 9 Dependiente de la Ciclina/genética , Quinasa 9 Dependiente de la Ciclina/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Espectrometría de Masas

RESUMEN

Optical refractometry techniques enable realization of both pressure and temperature directly from properties of the gas. The NIST refractometer, a fixed length optical cavity (FLOC) has previously been evaluated for operation as pressure standard, and now in this paper, is evaluated for the feasibility of operation as a primary temperature standard as well. The challenge is that during operation, one cavity is filled with gas. Gas dynamics predicts that this will result in heating which in turn will affect the cavity temperature uniformity, impeding the ability to measure the gas temperature with sufficient accuracy to make the standard useful as a primary standard for temperature or pressure. Temperature uniformity across the refractometer must be less than 0.5 mK for measurements of the refractivity to be sufficiently accurate for the FLOC. This paper compares computer modeling to laboratory measurements, enabling us to validate the model to predict thermal behavior and to accurately determine the measurement uncertainty of the technique. The results presented in this paper show that temperature of the glass elements of the refractometer and 'thermal-shell' copper chamber are equivalent to within 0.5 mK after an equilibration time of 3000 s (when going from 1 kPa to 100 kPa). This finding enables measurements of the copper chamber to determine the gas temperature to within an uncertainty (k = 1) of 0.5 mK. Additionally, the NIST refractometer is evaluated for feasibility of operation as temperature standard.

RESUMEN

AIMS AND OBJECTIVES: The study aimed to determine the factors which influence clinician behaviour and adherence to best practice when clinicians provide the initial care for paediatric burn patients admitted to a burns unit. BACKGROUND: Optimal initial care of burn patients influences morbidity and mortality. Non-burn specialist clinician adherence to best practice is influenced by previously unexplored factors. DESIGN: General inductive qualitative methods were used to explore factors which influenced clinicians providing acute pre-admission burn care for children in Western Australia. METHODS: Interviews of nineteen clinicians using standardised open-ended questions based on the Gilbert Behaviour Engineering Model were used to collect data. RESULTS: The main influencing factors identified were the telehealth service which supported practice, whilst IT issues provided challenges to clinicians. CONCLUSION: Telehealth services support clinicians when providing burn care, however IT issues are an major barrier to both best practice and accessing the telehealth service and should be optimised to support clinical care IMPACT STATEMENT: What does this paper contribute to the wider global community? It provides burn clinicians with an insight into the factors which facilitate optimal care for patients prior to transfer to burn units, as well as the barriers faced by non-burn specialist clinicians when patients initially present for care. Models of care which acknowledge these factors can help facilitate optimal patient care.

Asunto(s)

Unidades de Quemados/normas , Quemaduras , Quemaduras/terapia , Niño , Adhesión a Directriz , Hospitalización , Humanos , Telemedicina , Australia Occidental

RESUMEN

The NIST on a Chip (NOAC) program's central idea is the idea that measurement technology can be developed to enable metrology to be performed "outside the National Metrology Institute" by the creation of deployed and often miniaturized standards. These standards, when based on fundamental properties of nature, are directly tracible to the international system of units known as the SI. NIST is also developing quantum-based standards for SI traceability known as QSI, or Quantum based International System of units. Specifically, this paper will cover NIST efforts in the area of thermodynamic metrology to develop NOAC standards for pressure, vacuum and temperature measurements.

RESUMEN

Over the past decade, the field of forensic science has received recommendations from the National Research Council of the U.S. National Academy of Sciences, the U.S. National Institute of Standards and Technology, and the U.S. President's Council of Advisors on Science and Technology to study the validity and reliability of forensic analyses. More specifically, these committees recommend estimation of the rates of occurrence of erroneous conclusions drawn from forensic analyses. "Black box" studies for the various subjective feature-based comparison methods are intended for this purpose. In general, "black box" studies often have unbalanced designs, comparisons that are not independent, and missing data. These aspects pose difficulty in the analysis of the results and are often ignored. Instead, interpretation of the data relies on methods that assume independence between observations and a balanced experiment. Furthermore, all of these projects are interpreted within the frequentist framework and result in point estimates associated with confidence intervals that are confusing to communicate and understand. We propose to use an existing likelihood-free Bayesian inference method, called Approximate Bayesian Computation (ABC), that is capable of handling unbalanced designs, dependencies among the observations, and missing data. ABC allows for studying the parameters of interest without recourse to incoherent and misleading measures of uncertainty such as confidence intervals. By taking into account information from all decision categories for a given examiner and information from the population of examiners, our method also allows for quantifying the risk of error for the given examiner, even when no error has been recorded for that examiner. This opens the door to the detection of behavioural patterns in the decision-making of examiners through their ABC rate estimates. These patterns could be used to detect error prone examiners, enabling additional training efforts to be more tailored to each examiner, limiting the risk of errors before they occur. We illustrate our proposed method by reanalysing the results of the "Noblis Black Box" study by Ulery et al. [18]. We did not choose this study because we disagree with their results, but because it is a good example of a study with dependent observations and missing data, and the data is publicly available. The ABC estimates for the population generally agreed with Ulery et al.'s plug-in estimates. However, credible intervals obtained from ABC are much wider than the confidence intervals for the corresponding parameter estimates that did not account for the dependencies among observations.

RESUMEN

Mcl-1 is a member of the Bcl-2 family of proteins that promotes cell survival by preventing induction of apoptosis in many cancers. High expression of Mcl-1 causes tumorigenesis and resistance to anticancer therapies highlighting the potential of Mcl-1 inhibitors as anticancer drugs. Here, we describe AZD5991, a rationally designed macrocyclic molecule with high selectivity and affinity for Mcl-1 currently in clinical development. Our studies demonstrate that AZD5991 binds directly to Mcl-1 and induces rapid apoptosis in cancer cells, most notably myeloma and acute myeloid leukemia, by activating the Bak-dependent mitochondrial apoptotic pathway. AZD5991 shows potent antitumor activity in vivo with complete tumor regression in several models of multiple myeloma and acute myeloid leukemia after a single tolerated dose as monotherapy or in combination with bortezomib or venetoclax. Based on these promising data, a Phase I clinical trial has been launched for evaluation of AZD5991 in patients with hematological malignancies (NCT03218683).

Asunto(s)

Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Leucemia Mieloide Aguda/tratamiento farmacológico , Mieloma Múltiple/tratamiento farmacológico , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/antagonistas & inhibidores , Animales , Bortezomib/farmacología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Línea Celular Tumoral , Cristalografía por Rayos X , Humanos , Leucemia Mieloide Aguda/patología , Ratones , Ratones Endogámicos C57BL , Ratones SCID , Mieloma Múltiple/patología , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Ratas , Ratas Desnudas , Sulfonamidas/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto

RESUMEN

New techniques using refractometry have enabled gas pressure to be measured using laser interferometry. Two key techniques have been studied at NIST which include the Fixed Length Optical Cavity (FLOC) and the Variable Length Optical Cavity (VLOC). The measurement techniques are described and the traceability of these measurements through quantum mechanics that enables them to be primary standards. This technology is critical for gas pressure metrology to move away from artifact based standards (and especially mercury based) and move to quantum based methods for realization of the pascal.

RESUMEN

INTRODUCTION The aim of this study was to identify the rate of incisional hernia formation following ileostomy reversal in patients who underwent anterior resection for colorectal cancer. In addition, we aimed to ascertain risk factors for the development of reversal-site incisional hernias and to record the characteristics of the resultant hernias. MATERIALS AND METHODS Using a prospectively compiled database of colorectal cancer patients who were treated with anterior resection, we identified individuals who had undergone both ileostomy formation and subsequent reversal of their ileostomies from January 2005 to December 2014. Medical records were reviewed to record descriptive patient data about risk factors for hernia formation, operative details and any subsequent operations. Computed tomography reports were reviewed to identify the number, site and characteristics of incisional hernias. RESULTS A total of 121 patients were included in this study; 14.9% (n = 18) developed an incisional hernia at the ileostomy reversal site; 17.4% (n = 21) at a non-ileostomy site and 6.6% (n = 8) developed both. The reversal-site hernias were smaller both in width and length compared with the non-ileostomy-site hernias. Risk factors for the development of reversal-site incisional hernias were higher body mass index (BMI), lower age, open surgery, longer reversal time and a history of previous hernias. We did not detect a difference in the size of the incisional hernias that developed in patients with these specific risk factors. CONCLUSIONS Incisional hernias are a significant complication of ileostomy reversal. Further evaluation of the use of prophylactic mesh to reduce the incidence of incisional hernias may be worthwhile.

Asunto(s)

Hernia Abdominal/epidemiología , Ileostomía , Hernia Incisional/epidemiología , Complicaciones Posoperatorias/epidemiología , Neoplasias del Recto/cirugía , Recto/cirugía , Factores de Edad , Anciano , Índice de Masa Corporal , Quimioterapia Adyuvante , Neoplasias Colorrectales/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo , Femenino , Hernia Abdominal/diagnóstico por imagen , Humanos , Incidencia , Hernia Incisional/diagnóstico por imagen , Laparoscopía , Laparotomía , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Sobrepeso/epidemiología , Complicaciones Posoperatorias/diagnóstico por imagen , Radioterapia Adyuvante , Reoperación , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Tomografía Computarizada por Rayos X

RESUMEN

Epigenetic gene regulation is a dynamic process orchestrated by chromatin-modifying enzymes. Many of these master regulators exert their function through covalent modification of DNA and histone proteins. Aberrant epigenetic processes have been implicated in the pathophysiology of multiple human diseases. Small-molecule inhibitors have been essential to advancing our understanding of the underlying molecular mechanisms of epigenetic processes. However, the resolution offered by small molecules is often insufficient to manipulate epigenetic processes with high spatiotemporal control. Here we present a generalizable approach, referred to as 'chemo-optical modulation of epigenetically regulated transcription' (COMET), enabling high-resolution, optical control of epigenetic mechanisms based on photochromic inhibitors of human histone deacetylases using visible light. COMET probes may be translated into new therapeutic strategies for diseases where conditional and selective epigenome modulation is required.

Asunto(s)

Regulación de la Expresión Génica/efectos de la radiación , Luz , Optogenética/métodos , Compuestos Azo/química , Epigénesis Genética , Humanos , Células MCF-7 , Modelos Moleculares , Estructura Molecular

RESUMEN

Using confocal microscopy we investigate binary colloidal mixtures with large size asymmetry, in particular the formation of dynamically arrested states of the large spheres. The volume fraction of the system is kept constant, and as the concentration of small spheres is increased we observe a series of transitions of the large spheres to different arrested states: an attractive glass, a gel, and an asymmetric glass. These states are distinguished by the degree of dynamical arrest and the amount of structural and dynamical heterogeneity. The transitions between two different arrested states occur through melting and the formation of a fluid state. While a space-spanning network of bonded particles is found in both arrested and fluid states, only arrested states are characterized by the presence of a space-spanning network of dynamically arrested particles.

RESUMEN

In order to predict the fate of biodiversity in a rapidly changing world, we must first understand how species adapt to new environmental conditions. The long-term evolutionary dynamics of species' physiological tolerances to differing climatic regimes remain obscure. Here, we unite palaeontological and neontological data to analyse whether species' environmental tolerances remain stable across 3 Myr of profound climatic changes using 10 phylogenetically, ecologically and developmentally diverse mollusc species from the Atlantic and Gulf Coastal Plains, USA. We additionally investigate whether these species' upper and lower thermal tolerances are constrained across this interval. We find that these species' environmental preferences are stable across the duration of their lifetimes, even when faced with significant environmental perturbations. The results suggest that species will respond to current and future warming either by altering distributions to track suitable habitat or, if the pace of change is too rapid, by going extinct. Our findings also support methods that project species' present-day environmental requirements to future climatic landscapes to assess conservation risks.

Asunto(s)

Biodiversidad , Evolución Biológica , Cambio Climático , Ecosistema , Moluscos/fisiología , Animales , Moluscos/genética , Filogenia , Estados Unidos

RESUMEN

Small molecule fluorophores are indispensable tools for modern biomedical imaging techniques. In this report, we present the development of a new class of BODIPY dyes based on an alkoxy-fluoro-boron-dipyrromethene core. These novel fluorescent dyes, which we term MayaFluors, are characterized by good aqueous solubility and favorable in vitro physicochemical properties. MayaFluors are readily accessible in good yields in a one-pot, two-step approach starting from well-established BODIPY dyes, and allow for facile modification with functional groups of relevance to bioconjugate chemistry and bioorthogonal labeling. Biological profiling in living cells demonstrates excellent membrane permeability, low nonspecific binding, and lack of cytotoxicity.

Asunto(s)

Compuestos de Boro/análisis , Colorantes Fluorescentes/análisis , Imagen Molecular/métodos , Compuestos de Boro/síntesis química , Compuestos de Boro/química , Permeabilidad de la Membrana Celular , Supervivencia Celular , Femenino , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/química , Humanos , Células MCF-7 , Estructura Molecular , Solubilidad , Células Tumorales Cultivadas

RESUMEN

Three novel steroidal antiestrogen-geldanamycin conjugates were prepared using a convergent strategy. The antiestrogenic component utilized the 11ß-(4-functionalized-oxyphenyl) estradiol scaffold, while the geldanamycin component was derived by replacement of the 17-methoxy group with an appropriately functionalized amine. Ligation was achieved in high yield using azide alkyne cyclization reactions. Evaluation of the products against two breast cancer cell lines indicated that the conjugates retained significant antiproliferative activity.

Asunto(s)

Benzoquinonas/síntesis química , Benzoquinonas/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Antagonistas de Estrógenos/síntesis química , Antagonistas de Estrógenos/farmacología , Lactamas Macrocíclicas/síntesis química , Lactamas Macrocíclicas/farmacología , Benzoquinonas/química , Neoplasias de la Mama/metabolismo , Química Clic , Ensayos de Selección de Medicamentos Antitumorales , Antagonistas de Estrógenos/química , Femenino , Humanos , Lactamas Macrocíclicas/química , Células MCF-7 , Estructura Molecular

RESUMEN

INTRODUCTION: As part of our program to develop estrogen receptor (ER) targeted imaging and therapeutic agents we chose to evaluate 11ß-substituted estradiol analogs as a representative scaffold. Previous synthetic studies provided an entry into this class of compounds and other work indicated that 11ß-(substituted aryl) estradiol analogs were potent antagonists of the ER. Little information existed about the specific structural features involved in the transition from agonism to antagonism for the 11ß-aryl estradiol analogs or their potential as scaffolds for drug conjugation. METHODS: We prepared and characterized a series of 11ß-(4-Substituted phenyl) estradiol analogs using modifications of existing synthetic methods. The new compounds, as well as standard steroidal agonists and antagonists, were evaluated as competitive ligands for the ERß-LBD. Functional assays used the induction of alkaline phosphatase in Ishikawa cells to determine potency of the compounds as ER agonists or antagonists. RESULTS: The synthetic strategy successfully generated a series of compounds in which the 4-substituent was sequentially modified from hydroxyl to methoxy to azidoethoxy/N,N-dimethylaminoethoxy and eventually to a prototypical 1,4-naphthoquinone-containing moiety. The new compounds all retained high relative binding affinity (RBA) for the ERα-LBD, ranging from 13-83% that of estradiol. No subtype selectivity was observed. More importantly, the transition from agonist to antagonist activity occurs at the 4-methoxy stage where the compound is a mixed antagonist. More notably, antagonism appeared to be more dependent upon the size of the 11ß-substituent than upon the nature of the terminal group CONCLUSIONS: We have developed a synthetic strategy that provides facile access to potent 11ß-(4-substituted phenyl) estradiol analogs. The resultant compounds retain high affinity for the ERα-LBD and, more importantly, demonstrate potent antagonist activity in cells. Large functionalities distal to the 11ß-phenyl ring had little additional effect on either affinity or efficacy, suggesting the incorporation of diverse imaging or biologically active groups can be attached without significantly compromising the ER-binding capacity. Future studies are in progress to exploit the 11ß-aryl estradiol analogs as potential drug delivery systems and imaging agents.

Asunto(s)

Estradiol/síntesis química , Estradiol/farmacología , Receptor alfa de Estrógeno/agonistas , Receptor alfa de Estrógeno/antagonistas & inhibidores , Estradiol/análogos & derivados , Estradiol/química , Humanos , Estructura Molecular , Estereoisomerismo , Relación Estructura-Actividad

Asunto(s)

Compuestos de Boro/química , Radiofármacos/síntesis química , Ácidos/química , Anticuerpos Monoclonales Humanizados/química , Compuestos de Boro/síntesis química , Catálisis , Radioisótopos de Flúor/química , Tomografía de Emisión de Positrones , Radiofármacos/química , Temperatura , Trastuzumab

RESUMEN

As part of our program to develop breast cancer specific therapeutic agents, we have synthesized a conjugate agent that is a conjugate of the steroidal anti-estrogen and the potent cytotoxin doxorubicin. In this effort, we employed a modular assembly approach to prepare a novel 11ß-substituted steroidal anti-estrogen functionalized with an azido-tetraethylene glycol moiety, which could be coupled to a complementary doxorubicin benzoyl hydrazone functionalized with a propargyl tetraethylene glycol moiety. Huisgen [3 + 2] cycloaddition chemistry gave the final hybrid that was evaluated for selective uptake and cytotoxicity in ER(+)-MCF-7 and ER(-)-MDA-MB-231 breast cancer cell lines. The results demonstrated that the presence of the anti-estrogenic component in the hybrid compound was critical for selectivity and cytotoxicity in ER(+)-MCF-7 human breast cancer cells as the hybrid was ~70-fold more potent than doxorubicin in inhibition of cell proliferation and promoting cell death.

Asunto(s)

Neoplasias de la Mama/metabolismo , Doxorrubicina/química , Doxorrubicina/uso terapéutico , Diseño de Fármacos , Antagonistas de Estrógenos/química , Terapia Molecular Dirigida , Receptores de Estrógenos/metabolismo , Esteroides/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Doxorrubicina/síntesis química , Doxorrubicina/farmacología , Humanos , Concentración 50 Inhibidora

RESUMEN

The preparation and characterization of a novel nitroxide spin probe based on a steroidal anti-estrogen is described. The probe 5 demonstrated very high binding affinity for both the alpha and beta isoforms of the estrogen receptor-ligand binding domain. EPR spectrometric studies demonstrate conformational constraints for the ligand, consistent with the nitroxyl moiety occupying a position just beyond the receptor-solvent interface.

Asunto(s)

Antagonistas de Estrógenos/síntesis química , Receptor alfa de Estrógeno/metabolismo , Receptores de Estrógenos/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Antagonistas de Estrógenos/química , Antagonistas de Estrógenos/farmacología , Receptor alfa de Estrógeno/efectos de los fármacos , Ligandos , Modelos Moleculares , Estructura Molecular , Óxidos de Nitrógeno/química , Unión Proteica/efectos de los fármacos , Isoformas de Proteínas/metabolismo , Estructura Terciaria de Proteína , Receptores de Estrógenos/efectos de los fármacos

RESUMEN

Histone deacetylases (HDACs) are a group of enzymes that modulate gene expression and cell state by deacetylation of both histone and non-histone proteins. A variety of HDAC inhibitors (HDACi) have already undergone clinical testing in cancer. Real-time in vivo imaging of HDACs and their inhibition would be invaluable; however, the development of appropriate imaging agents has remained a major challenge. Here, we describe the development and evaluation of (18)F-suberoylanilide hydroxamic acid ((18)F-SAHA 1a), a close analogue of the most clinically relevant HDAC inhibitor suberoylanilide hydroxamic acid (SAHA). We demonstrate that 1a has near identical biochemical activity profiles to that of SAHA and report findings from pharmacokinetic studies. Using a murine ovarian cancer model, we likewise show that HDAC inhibitor target binding efficacy can be quantitated within 24 h of administration. 1a thus represents the first (18)F-positron emission tomography (PET) HDAC imaging agent, which also exhibits low nanomolar potency and is pharmacologically analogous to a clinically relevant HDAC inhibitor.

Asunto(s)

Radioisótopos de Flúor , Inhibidores de Histona Desacetilasas , Ácidos Hidroxámicos , Animales , Histona Desacetilasas/metabolismo , Ratones , Ratones Endogámicos C57BL , Vorinostat