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1.
CBE Life Sci Educ ; 21(3): ar47, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35816448

RESUMEN

Learning molecular biology involves using visual representations to communicate ideas about largely unobservable biological processes and molecules. Genes and gene expression cannot be directly visualized, but students are expected to learn and understand these and related concepts. Theoretically, textbook illustrations should help learners master such concepts, but how are genes and other DNA-linked concepts illustrated for learners? We examined all DNA-related images found in 12 undergraduate biology textbooks to better understand what biology students encounter when learning concepts related to DNA. Our analysis revealed a wide array of DNA images that were used to design a new visual framework, the DNA Landscape, which we applied to more than 2000 images from common introductory and advanced biology textbooks. All DNA illustrations could be placed on the landscape framework, but certain positions were more common than others. We mapped figures about "gene expression" and "meiosis" onto the landscape framework to explore how these challenging topics are illustrated for learners, aligning these outcomes with the research literature to showcase how the overuse of certain representations may hinder, instead of help, learning. The DNA Landscape is a tool to promote research on visual literacy and to guide new learning activities for molecular biology.


Asunto(s)
Aprendizaje , Estudiantes , ADN/genética , Humanos , Alfabetización
2.
J Mater Cycles Waste Manag ; 24(4): 1603-1611, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35570848

RESUMEN

This study aimed to quantify the amount of pharmaceutical waste produced in New Zealand, and determine the composition of pharmaceutical waste from community pharmacies in Auckland, New Zealand. Pharmaceutical waste collected in New Zealand is increasing, peaking at 542 tonne in 2019. Pharmaceutical waste collected from hospitals and pharmacies in Auckland increased by more than fourfold from 2016 to 2020. An audit of the types of pharmaceutical waste collected from community pharmacies revealed that the most common classes of drugs identified in this waste stream belonged to the nervous system, cardiovascular system and alimentary tract, and metabolism. Following examination of the contents of 12 pharmaceutical waste bins, 475 different pharmaceutical products were identified, highlighting the breadth of drugs in this waste stream. A range of dosage forms and hence materials were identified, which could present challenges for future waste treatment approaches. Hazardous drugs were identified including cytotoxic compounds, which should go into a separate waste stream for incineration. There is a need for similar data to be collected from multiple sites to fully appreciate the magnitude and composition of pharmaceutical waste. This will allow for the suitability of current practices for managing this hazardous waste stream to be evaluated.

3.
Angew Chem Int Ed Engl ; 61(18): e202201700, 2022 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-35194905

RESUMEN

A strategy for the generation of heterotrimetallic double cavity (DC) cages [Pdn Ptm L4 ]6+ (DC1: n=1, m=2; and DC2: n=2, m=1) is reported. The DC cages were generated by combining an inert platinum(II) tetrapyridylaldehyde complex with a suitably substituted pyridylamine and PdII ions. 1 H and DOSY nuclear magnetic resonance spectroscopy (NMR) and electrospray ionization mass spectrometry (ESIMS) data were consistent with the formation of the DC architectures. DC1 and DC2 were shown to interact with several different guest molecules. The structure of DC1, which features two identical cavities, binding two 2,6-diaminoanthraquinone (DAQ) guest molecules was determined by single-crystal X-ray crystallography. In addition, DC1 was shown to bind two molecules of 5-fluorouracil (5-FU) in a statistical (non-cooperative) manner. In contrast, DC2, which features two different cage cavities, was found to interact with two different guests, 5-FU and cisplatin, selectively.


Asunto(s)
Fluorouracilo , Platino (Metal) , Cristalografía por Rayos X , Espectroscopía de Resonancia Magnética
4.
Sci Rep ; 11(1): 23626, 2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34880294

RESUMEN

We show a method to control magnetic interfacial effects in multilayers with Dzyaloshinskii-Moriya interaction (DMI) using helium (He[Formula: see text]) ion irradiation. We report results from SQUID magnetometry, ferromagnetic resonance as well as Brillouin light scattering results on multilayers with DMI as a function of irradiation fluence to study the effect of irradiation on the magnetic properties of the multilayers. Our results show clear evidence of the He[Formula: see text] irradiation effects on the magnetic properties which is consistent with interface modification due to the effects of the He[Formula: see text] irradiation. This external degree of freedom offers promising perspectives to further improve the control of magnetic skyrmions in multilayers, that could push them towards integration in future technologies.

5.
Front Chem ; 9: 786367, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34926406

RESUMEN

Multimetallic complexes have been shown in several examples to possess greater anticancer activity than their monometallic counterparts. The increased activity has been attributed to altered modes of action. We herein report the synthesis of a series of heterodimetallic compounds based on a ditopic ligand featuring 2-pyridylimine chelating motifs and organometallic half-sandwich moieties. The complexes were characterized by a combination of 1H NMR spectroscopy, electrospray ionization mass spectrometry, elemental analysis and single crystal X-ray diffraction. Investigations into the stability of representative complexes in DMSO-d 6 and 10% DMSO-d 6 /D2O revealed the occurrence of solvent-chlorido ligand exchange. Proliferation assays in four human cancer cell lines showed that the Os-Rh complex possessed minimal activity, while all other complexes were inactive.

6.
CBE Life Sci Educ ; 20(4): ar53, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34546102

RESUMEN

Concepts of molecular biology and genetics are difficult for many biology undergraduate students to master yet are crucial for deep understanding of how life works. By asking students to draw their ideas, we attempted to uncover the mental models about genes and gene expression held by biology students (n = 23) and experts (n = 18) using semistructured interviews. A large divide was identified between novice and expert conceptions. While experts typically drew box-and-line representations and thought about genes as regions of DNA that were used to encode products, students typically drew whole chromosomes rather than focusing on gene structure and conflated gene expression with simple phenotypic outcomes. Experts universally described gene expression as a set of molecular processes involving transcription and translation, whereas students often associated gene expression with Punnett squares and phenotypic outcomes. Follow-up survey data containing a ranking question confirmed students' alignment of their mental models with the images uncovered during interviews (n = 156 undergraduate biology students) and indicated that Advanced students demonstrate a shift toward expert-like thinking. An analysis of 14 commonly used biology textbooks did not show any relationship between Punnett squares and discussions of gene expression, so it is doubtful students' ideas originate directly from textbook reading assignments. Our findings add to the literature about mechanistic reasoning abilities of learners and provide new insights into how biology students think about genes and gene expression.


Asunto(s)
Biología Molecular , Estudiantes , Biología , ADN , Expresión Génica , Humanos , Solución de Problemas
9.
Front Chem ; 9: 697684, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34307299

RESUMEN

Two new di(2,2'-bipyridine) ligands, 2,6-bis([2,2'-bipyridin]-5-ylethynyl)pyridine (L1) and bis(4-([2,2'-bipyridin]-5-ylethynyl)phenyl)methane (L2) were synthesized and used to generate two metallosupramolecular [Fe2(L)3](BF4)4 cylinders. The ligands and cylinders were characterized using elemental analysis, electrospray ionization mass spectrometry, UV-vis, 1H-, 13C and DOSY nuclear magnetic resonance (NMR) spectroscopies. The molecular structures of the [Fe2(L)3](BF4)4 cylinders were confirmed using X-ray crystallography. Both the [Fe2(L1)3](BF4)4 and [Fe2(L2)3](BF4)4 complexes crystallized as racemic (rac) mixtures of the ΔΔ (P) and ΛΛ (M) helicates. However, 1H NMR spectra showed that in solution the larger [Fe2(L2)3](BF4)4 was a mixture of the rac-ΔΔ/ΛΛ and meso-ΔΛ isomers. The host-guest chemistry of the helicates, which both feature a central cavity, was examined with several small drug molecules. However, none of the potential guests were found to bind within the helicates. In vitro cytotoxicity assays demonstrated that both helicates were active against four cancer cell lines. The smaller [Fe2(L1)3](BF4)4 system displayed low µM activity against the HCT116 (IC50 = 7.1 ± 0.5 µM) and NCI-H460 (IC50 = 4.9 ± 0.4 µM) cancer cells. While the antiproliferative effects against all the cell lines examined were less than the well-known anticancer drug cisplatin, their modes of action would be expected to be very different.

10.
Chembiochem ; 22(15): 2521-2525, 2021 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-34137488

RESUMEN

Hypoxia-inducible factor prolyl hydroxylase domain 2 (PHD2) is an important oxygen sensor in animals. By using the CO-releasing molecule-2 (CORM-2) as an in situ CO donor, we demonstrate that CO is an inhibitor of PHD2. This report provides further evidence about the emerging role of CO in oxygen sensing and homeostasis.


Asunto(s)
Prolina Dioxigenasas del Factor Inducible por Hipoxia
11.
Artículo en Inglés | MEDLINE | ID: mdl-32913487

RESUMEN

Topics related to energy transformation and metabolism are important parts of an undergraduate biology curriculum, but these are also topics that students traditionally struggle with. To address this, we have created a short online Interactive Video Vignette (IVV) called To Ferment or Not to Ferment: That is the Question. This IVV is designed to help students learn important ideas related to cellular respiration and metabolism. Students in various courses across four institutions were assigned the IVV as an out-of-class preinstruction homework assignment. To test the effectiveness of this IVV on student learning, we collected and analyzed data from questions embedded in the IVV, open response reflection questions, and pre- and postassessments from IVV watchers and nonwatchers. Our analysis revealed that students who completed the IVV activity interacted productively with this online tool and made significant learning gains on important topics related to cellular respiration and metabolism. This IVV is freely available via https://www.rit.edu/cos/interactive/MINT for instructors to adopt for class use.

12.
Trials ; 21(1): 542, 2020 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-32552857

RESUMEN

BACKGROUND: Most individuals with dementia or mild cognitive impairment (MCI) have multiple chronic conditions (MCC). The combination leads to multiple medications and complex medication regimens and is associated with increased risk for significant treatment burden, adverse drug events, cognitive changes, hospitalization, and mortality. Optimizing medications through deprescribing (the process of reducing or stopping the use of inappropriate medications or medications unlikely to be beneficial) may improve outcomes for MCC patients with dementia or MCI. METHODS: With input from patients, family members, and clinicians, we developed and piloted a patient-centered, pragmatic intervention (OPTIMIZE) to educate and activate patients, family members, and primary care clinicians about deprescribing as part of optimal medication management for older adults with dementia or MCI and MCC. The clinic-based intervention targets patients on 5 or more medications, their family members, and their primary care clinicians using a pragmatic, cluster-randomized design at Kaiser Permanente Colorado. The intervention has two components: a patient/ family component focused on education and activation about the potential value of deprescribing, and a clinician component focused on increasing clinician awareness about options and processes for deprescribing. Primary outcomes are total number of chronic medications and total number of potentially inappropriate medications (PIMs). We estimate that approximately 2400 patients across 9 clinics will receive the intervention. A comparable number of patients from 9 other clinics will serve as wait-list controls. We have > 80% power to detect an average decrease of - 0.70 (< 1 medication). Secondary outcomes include the number of PIM starts, dose reductions for selected PIMs (benzodiazepines, opiates, and antipsychotics), rates of adverse drug events (falls, hemorrhagic events, and hypoglycemic events), ability to perform activities of daily living, and skilled nursing facility, hospital, and emergency department admissions. DISCUSSION: The OPTIMIZE trial will examine whether a primary care-based, patient- and family-centered intervention educating patients, family members, and clinicians about deprescribing reduces numbers of chronic medications and PIMs for older adults with dementia or MCI and MCC. TRIAL REGISTRATION: NCT03984396. Registered on 13 June 2019.


Asunto(s)
Deprescripciones , Educación del Paciente como Asunto/métodos , Atención Dirigida al Paciente/organización & administración , Lista de Medicamentos Potencialmente Inapropiados/estadística & datos numéricos , Atención Primaria de Salud/métodos , Disfunción Cognitiva/tratamiento farmacológico , Colorado , Demencia/tratamiento farmacológico , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Familia , Hospitalización , Humanos , Afecciones Crónicas Múltiples , Polifarmacia , Ensayos Clínicos Pragmáticos como Asunto
13.
Angew Chem Int Ed Engl ; 59(27): 11101-11107, 2020 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-32220036

RESUMEN

A strategy is presented that enables the quantitative assembly of a heterobimetallic [PdPtL4 ]4+ cage. The presence of two different metal ions (PdII and PtII ) with differing labilities enables the cage to be opened and closed selectively at one end upon treatment with suitable stimuli. Combining an inert PtII tetrapyridylaldehyde complex with a suitably substituted pyridylamine and PdII ions led to the assembly of the cage. 1 H and DOSY NMR spectroscopy and ESI mass spectrometry data were consistent with the quantitative formation of the cage, and the heterobimetallic structure was confirmed using single-crystal X-ray crystallography. The structure of the host-guest adduct with a 2,6-diaminoanthraquinone guest molecule was determined. Addition of N,N'-dimethylaminopyridine (DMAP) resulted in the formation of the open-cage [PtL4 ]2+ compound and [Pd(DMAP)4 ]2+ complex. This process could then be reversed, with the reformation of the cage, upon addition of p-toluenesulfonic acid (TsOH).

15.
Public Health ; 176: 21-28, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31679636

RESUMEN

BACKGROUND: The nutrition transition continues to affect populations throughout the world. The added impact of market integration and urbanization exacerbates the impact of the nutrition transition upon Indigenous populations worldwide. OBJECTIVES: This study aims to explore the nutritional concerns of the urban Kichwas community residing in the Andes highlands of Ecuador. STUDY DESIGN: This is a qualitative study. METHODS: Eight focus groups were conducted with Kichwas men and women in November 2015 in the Imbabura province of the Andes in Ecuador. DATA ANALYSIS: Applied thematic analysis was used to analyze findings regarding nutrition. RESULTS: The participants shared concerns regarding increased intake of fast food, poor meal timing, and a shift in the child's food preferences that rejects traditional foods. They attributed these concerns to urbanization resulting from an increase in dual-income households and a loss of cultural identity. CONCLUSIONS: Synergistic cultural factors are related to nutritional concerns voiced by the urban Kichwas community. PUBLIC HEALTH IMPLICATIONS: Syndemic theory is a useful interpretive lens regarding nutritional trends within the Kichwas communities as they relate to the increased risk of chronic disease.


Asunto(s)
Estado Nutricional , Grupos de Población/estadística & datos numéricos , Población Urbana/estadística & datos numéricos , Urbanización , Adulto , Enfermedad Crónica , Ecuador , Femenino , Grupos Focales , Humanos , Masculino
16.
Diabet Med ; 36(6): 665-678, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30801765

RESUMEN

Intensive insulin therapy is the mainstay of treatment for people with Type 1 diabetes, but hypoglycaemia and weight gain are often limiting factors in achieving glycaemic targets and decreasing the risk of diabetes-related complications. The inclusion of pharmacological agents used traditionally in Type 2 diabetes as adjuncts to insulin therapy in Type 1 diabetes has been explored, with the goal of mitigating such drawbacks. Pramlintide and metformin result in modest HbA1c and weight reductions, but their use is limited by poor tolerability and, in the case of pramlintide, by frequency of injections and cost. The addition of glucagon-like peptide-1 receptor agonists to insulin results in improved glycaemic control, reduced insulin doses and weight loss, but this is at the expense of higher rates of hypoglycaemia and hyperglycaemia with ketosis. Sodium-glucose co-transporter-2 and dual sodium-glucose co-transporter-2 and -1 inhibitors also improve glucose control, but with reductions in weight and insulin requirements potentiating the risk of acidosis-related events and hypoglycaemia. The high proportion of people with Type 1 diabetes not achieving glycaemic targets, the negative clinical impact of intensive insulin therapy and the rise in obesity and cardiovascular disease and mortality, underline the need for individualized clinical care. The evaluation of new therapies, effective in Type 2 diabetes, as adjuncts to insulin therapy represents a promising strategy, particularly given the beneficial effects on cardiovascular and renal outcomes in people with Type 2 diabetes with or at high risk of complications that are also observed in patients with Type 1 diabetes. As the population with Type 1 diabetes ages, our mission is to evolve and provide better tools and improved therapies to excel, not only in glycaemic control but also in risk reduction and reduction of complications.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Endocrinología/tendencias , Hipoglucemiantes/clasificación , Hipoglucemiantes/uso terapéutico , Terapias en Investigación/tendencias , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Endocrinología/métodos , Humanos , Metformina/uso terapéutico , Terapias en Investigación/métodos , Tiazolidinedionas/uso terapéutico
17.
Biochem Mol Biol Educ ; 46(5): 435-444, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30281894

RESUMEN

The essence of molecular biology education lies in understanding of gene expression, with subtopics including the central dogma processes, such as transcription and translation. While these concepts are core to the discipline, they are also notoriously difficult for students to learn, probably because they cannot be directly observed. While nearly all active learning strategies have been shown to improve learning compared with passive lectures, little has been done to compare different types of active learning. We hypothesized that physical models of central dogma processes would be especially helpful for learning, because they provide a resource that students can see, touch, and manipulate while trying to build their knowledge. For students enrolled in an entirely active-learning-based Cell & Molecular Biology course, we examined whether model-based activities were more effective than non-model based activities. To test their understanding at the beginning and end of the semester, we employed the multiple-select Central Dogma Concept Inventory (CDCI). Each student acted as their own control, as all students engaged in all lessons yet some questions related to model-based activities and some related to clicker questions, group problem-solving, and other non-model-based activities. While all students demonstrated learning gains on both types of question, they showed much higher learning gains on model-based questions. Examining their selected answers in detail showed that while higher performing students were prompted to refine their already-good mental models to be even better, lower performing students were able to construct new knowledge that was much more consistent with an expert's understanding. © 2018 The Authors. Biochemistry and Molecular Biology Education published by Wiley Periodicals, Inc. on behalf of International Union of Biochemistry and Molecular Biology., 46(5):435-444, 2018.


Asunto(s)
Aprendizaje , Modelos Biológicos , Biología Molecular/educación , Estudiantes
18.
Rev Sci Instrum ; 89(1): 014102, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29390723

RESUMEN

We present the details of a fast ion velocity map imaging mass spectrometer that is capable of imaging the photofragments of trap-cooled (≥7 K) ions produced in a versatile ion source. The new instrument has been used to study the predissociation of N2O+ produced by electric discharge and the direct dissociation of Al2+ formed by laser ablation. The instrument's resolution is currently limited by the diameter of the collimating iris to a value of Δv/v = 7.6%. Photofragment images of N2O+ show that when the predissociative state is changed from 2Σ+(200) to 2Σ+(300) the dominant product channel shifts from a spin-forbidden ground state, N (4S) + NO+(v = 5), to a spin-allowed pathway, N*(2D) + NO+. The first photofragment images of Al2+ confirm the existence of a directly dissociative parallel transition (2Σ+u ← 2Σ+g) that yields products with a large amount of kinetic energy. D0 of ground state Al2+ (2Σ+g) measured from these images is 138 ± 5 kJ/mol, which is consistent with the published literature.

19.
Chemistry ; 24(17): 4304-4309, 2018 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-29114951

RESUMEN

The first examples of amino-substituted fused-ring metallabenzenes, the cationic iridabenzofuran [Ir(C7 H4 O{NH2 -2}{OMe-7})(CO)(PPh3 )2 ][O3 SCF3 ] (5) and neutral analogue Ir(C7 H4 {NH2 -2}{OMe-7})Cl(PPh3 )2 (6), can be prepared by reduction of the corresponding nitro-substituted iridabenzofurans with zinc and concentrated hydrochloric acid. N-functionalised derivatives of 5 and 6 are formed through alkylation, sulfonylation or acylation. Thus, consecutive treatments with methyl triflate and base gives the corresponding trimethylammonium-substituted iridabenzofurans while sulfonamide derivatives are formed with p-toluenesulfonyl chloride. N-Acylation of 5 or 6 with acid chlorides, however, selectively form either amide or imide products depending on the charge on the metal and the steric size of the acid chloride. Cationic 5 gives amide substituted products regardless of the conditions whereas neutral 6 rapidly undergoes di-N-acylation with excess benzoyl chloride under mild conditions to give the imide-substituted product Ir(C7 H4 O{N[C(O)Ph]2 -2}{OMe-7})Cl(PPh3 )2 (13). Selective mono-acylation of 6 can be achieved with one equivalent of benzoyl chloride or with excess of the sterically congested pivaloyl chloride.

20.
Chemistry ; 24(9): 2025-2038, 2018 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-29193396

RESUMEN

Metallaaromatics can be broadly defined as aromatic compounds in which one of the ring atoms is a transition metal. The metallabenzenes are one important class of these compounds that has undergone extensive study recently. Closely related species such as fused-ring metallabenzenes, heterometallabenzenes, π-coordinated metallabenzenes and metallabenzynes have also attracted considerable attention. Although many metallaaromatics can be considered as metalla-analogues of classic organic aromatic compounds, this is not always the case. Recent seminal studies have shown that metallapentalenes and metallapentalynes, which are metalla-analogues of the anti-aromatic compounds pentalene and pentalyne, are in fact aromatic and highly stable. Very unusual spiro-metallaaromatic compounds have also recently been isolated. In this concepts article, key features of all these intriguing metallaaromatic compounds are discussed with reference to the structural, spectroscopic, reactivity and theoretical studies that have been undertaken. These compounds continue to generate much interest, not only because of the contributions they make to fundamental chemical understanding, but also because of the promise of possible practical applications.

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