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1.
Nature ; 593(7857): 61-66, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953410

RESUMO

In only a few decades, lithium-ion batteries have revolutionized technologies, enabling the proliferation of portable devices and electric vehicles1, with substantial benefits for society. However, the rapid growth in technology has highlighted the ethical and environmental challenges of mining lithium, cobalt and other mineral ore resources, and the issues associated with the safe usage and non-hazardous disposal of batteries2. Only a small fraction of lithium-ion batteries are recycled, further exacerbating global material supply of strategic elements3-5. A potential alternative is to use organic-based redox-active materials6-8 to develop rechargeable batteries that originate from ethically sourced, sustainable materials and enable on-demand deconstruction and reconstruction. Making such batteries is challenging because the active materials must be stable during operation but degradable at end of life. Further, the degradation products should be either environmentally benign or recyclable for reconstruction into a new battery. Here we demonstrate a metal-free, polypeptide-based battery, in which viologens and nitroxide radicals are incorporated as redox-active groups along polypeptide backbones to function as anode and cathode materials, respectively. These redox-active polypeptides perform as active materials that are stable during battery operation and subsequently degrade on demand in acidic conditions to generate amino acids, other building blocks and degradation products. Such a polypeptide-based battery is a first step to addressing the need for alternative chemistries for green and sustainable batteries in a future circular economy.


Assuntos
Fontes de Energia Elétrica , Eletroquímica , Peptídeos/química , Animais , Bovinos , Linhagem Celular , Sobrevivência Celular , Óxidos N-Cíclicos/química , Camundongos , Osteoblastos/citologia , Oxirredução , Peptídeos/síntese química , Desenvolvimento Sustentável , Viologênios/química
2.
J Neurosci ; 42(1): 69-80, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34759032

RESUMO

When presented with a periodic stimulus, humans spontaneously adjust their movements from reacting to predicting the timing of its arrival, but little is known about how this sensorimotor adaptation changes across development. To investigate this, we analyzed saccade behavior in 114 healthy humans (ages 6-24 years) performing the visual metronome task, who were instructed to move their eyes in time with a visual target that alternated between two known locations at a fixed rate, and we compared their behavior to performance in a random task, where target onsets were randomized across five interstimulus intervals (ISIs) and thus the timing of appearance was unknown. Saccades initiated before registration of the visual target, thus in anticipation of its appearance, were labeled predictive [saccade reaction time (SRT) < 90 ms] and saccades that were made in reaction to its appearance were labeled reactive (SRT > 90 ms). Eye-tracking behavior including saccadic metrics (e.g., peak velocity, amplitude), pupil size following saccade to target, and blink behavior all varied as a function of predicting or reacting to periodic targets. Compared with reactive saccades, predictive saccades had a lower peak velocity, a hypometric amplitude, smaller pupil size, and a reduced probability of blink occurrence before target appearance. The percentage of predictive and reactive saccades changed inversely from ages 8-16, at which they reached adult-levels of behavior. Differences in predictive saccades for fast and slow target rates are interpreted by differential maturation of cerebellar-thalamic-striatal pathways.SIGNIFICANCE STATEMENT From the first moments of life, humans are exposed to rhythm (i.e., mother's heartbeat in utero), but the timeline of brain development to promote the identification and anticipation of a rhythmic stimulus, known as temporal prediction, remains unknown. Here, we used saccade reaction time (SRT) in the visual metronome task to differentiate between temporally predictive and reactive responses to a target that alternated at a fixed rate in humans aged 6-24. Periods of age-related change varied little by target rate, with matured predictive performance evident by mid-adolescence for fast and slow rates. A strong correlation among saccade, pupil, and blink responses during target prediction provides evidence of oculomotor coordination and dampened noradrenergic neuronal activity when generating rhythmic motor responses.


Assuntos
Adaptação Fisiológica/fisiologia , Piscadela/fisiologia , Tempo de Reação/fisiologia , Movimentos Sacádicos/fisiologia , Adolescente , Criança , Feminino , Humanos , Masculino , Estimulação Luminosa , Pupila , Adulto Jovem
3.
BMC Public Health ; 23(1): 655, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-37020282

RESUMO

BACKGROUND: Post-secondary students frequently experience high rates of mental health challenges. However, they present meagre rates of treatment-seeking behaviours. This elevated prevalence of mental health problems, particularly after the COVID-19 pandemic, can lead to distress, poor academic performance, and lower job prospects following the completion of education. To address the needs of this population, it is important to understand students' perceptions of mental health and the barriers preventing or limiting their access to care. METHODS: A broad-scoping online survey was publicly distributed to post-secondary students, collecting demographic, sociocultural, economic, and educational information while assessing various components of mental health. RESULTS: In total, 448 students across post-secondary institutions in Ontario, Canada, responded to the survey. Over a third (n = 170; 38.6%) of respondents reported a formal mental health diagnosis. Depression and generalized anxiety disorder were the most commonly reported diagnoses. Most respondents felt that post-secondary students did not have good mental health (n = 253; 60.5%) and had inadequate coping strategies (n = 261; 62.4%). The most frequently reported barriers to care were financial (n = 214; 50.5%), long wait times (n = 202; 47.6%), insufficient resources (n = 165; 38.9%), time constraints (n = 148; 34.9%), stigma (n = 133; 31.4%), cultural barriers (n = 108; 25.5%), and past negative experiences with mental health care (n = 86; 20.3%). The majority of students felt their post-secondary institution needed to increase awareness (n = 231; 56.5%) and mental health resources (n = 306; 73.2%). Most viewed in-person therapy and online care with a therapist as more helpful than self-guided online care. However, there was uncertainty about the helpfulness and accessibility of different forms of treatment, including online interventions. The qualitative findings highlighted the need for personal strategies, mental health education and awareness, and institutional support and services. CONCLUSIONS: Various barriers to care, perceived lack of resources, and low knowledge of available interventions may contribute to compromised mental health in post-secondary students. The survey findings indicate that upstream approaches such as integrating mental health education for students may address the varying needs of this critical population. Therapist-involved online mental health interventions may be a promising solution to address accessibility issues.


Assuntos
COVID-19 , Saúde Mental , Humanos , Estudos Transversais , Pandemias , Estudantes , Ontário
4.
Nano Lett ; 21(12): 4990-4998, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34115938

RESUMO

Platelet-like and cylindrical nanostructures from sugar-based polymers are designed to mimic the aspect ratio of bacteria and achieve uroepithelial cell binding and internalization, thereby improving their potential for local treatment of recurrent urinary tract infections. Polymer nanostructures, derived from amphiphilic block polymers composed of zwitterionic poly(d-glucose carbonate) and semicrystalline poly(l-lactide) segments, were constructed with morphologies that could be tuned to enhance uroepithelial cell binding. These nanoparticles exhibited negligible cytotoxicity, immunotoxicity, and cytokine adsorption, while also offering substantial silver cation loading capacity, extended release, and in vitro antimicrobial activity (as effective as free silver cations) against uropathogenic Escherichia coli. In comparison to spherical analogues, cylindrical and platelet-like nanostructures engaged in significantly higher association with uroepithelial cells, as measured by flow cytometry; despite their larger size, platelet-like nanostructures maintained the capacity for cell internalization. This work establishes initial evidence of degradable platelet-shaped nanostructures as versatile therapeutic carriers for treatment of epithelial infections.


Assuntos
Nanopartículas , Polímeros , Antibacterianos/farmacologia , Prata , Açúcares
5.
Nano Lett ; 20(9): 6563-6571, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32787153

RESUMO

Interactions between drug molecules, nanocarrier components, and surrounding media influence the properties and therapeutic efficacies of nanomedicines. In this study, we investigate the role that reversible covalent loading of a hydrophobic drug exerts on intra-nanoparticle physical properties and explore the utility of this payload control strategy for tuning the access of active agents and, thereby, the stimuli sensitivity of smart nanomaterials. Glutathione sensitivity was controlled via altering the degree of hydrophobic payload loading of disulfide-linked camptothecin-conjugated sugar-based nanomaterials. Increases in degrees of camptothecin conjugation (fCPT) decreased aqueous accessibility and reduced glutathione-triggered release. Although the lowest fCPT gave the fastest camptothecin release, it resulted in the lowest camptothecin concentration. Remarkably, the highest fCPT resulted in a 5.5-fold improved selectivity against cancer vs noncancerous cells. This work represents an advancement in drug carrier design by demonstrating the importance of controlling the amount of drug loading on the overall payload and its availability.


Assuntos
Portadores de Fármacos , Nanopartículas , Camptotecina/farmacologia , Interações Hidrofóbicas e Hidrofílicas , Nanomedicina
6.
Inorg Chem ; 59(23): 16998-17008, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33185436

RESUMO

Rates of NO release from synthetic dinitrosyl iron complexes (DNICs) are shown to be responsive to coordination environments about iron. The effect of biologically relevant cellular components, glutathione and histidine, on the rate of NO release from a dimeric, "Roussin's Red Ester", DNIC with bridging µ-S thioglucose ligands, SGlucRRE or [(µ-SGluc)Fe(NO)2]2 (SGluc = 1-thio-ß-d-glucose tetraacetate), was investigated. From the Griess assay and X-band EPR data, decomposition of the product from the histidine-cleaved dimer, [(SGluc)(NHis)Fe(NO)2], generated Fe(III) and increased the NO release rate in aqueous media when compared to the intact SGlucRRE precursor. In contrast, increasing concentrations of exogenous glutathione generated the stable [(SGluc)(GS)Fe(NO)2]- anion and depressed the rate of NO release. Both of the cleaved, monomeric intermediates were characterized with ESI-MS, EPR, and FT-IR spectroscopies. On the basis of the Griess assay coupled with data from an intracellular fluorometric probe, both the monomeric DNICs and dimeric SGlucRRE diffuse into smooth muscle cells, chosen as appropriate archetypes of vascular relaxation, and release their NO payload. Ultimately, this work provides insight into tuning NO release beyond the design of DNICs, through the incubation with safe, accessible biological molecules.


Assuntos
Glutationa/química , Histidina/química , Ferro/química , Óxido Nítrico/química , Óxidos de Nitrogênio/química , Células Cultivadas , Espectroscopia de Ressonância de Spin Eletrônica , Fluorescência , Humanos , Conformação Molecular , Óxidos de Nitrogênio/síntese química
7.
Can J Psychiatry ; 65(1): 5-15, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31558033

RESUMO

BACKGROUND: Evidence regarding the efficacy of psychotherapy in adolescents with borderline personality disorder (BPD) symptomatology has not been previously synthesized. OBJECTIVE: To conduct a systematic review and meta-analysis of the randomized controlled trials (RCTs) in order to assess the efficacy of psychotherapies in adolescents with BPD symptomatology. METHODS: Seven electronic databases were systematically searched using the search terms BPD, adolescent, and psychotherapy from database inception to July 2019. Titles/abstracts and full-texts were screened by one reviewer; discrepancies were resolved via consensus. We extracted data on BPD symptomatology, including BPD symptoms, suicide attempts, nonsuicidal self-injury, general psychopathology, functional recovery, and treatment retention. Data were pooled using random-effects models. RESULTS: Of 536 papers, seven trials (643 participants) were eligible. Psychotherapy led to significant short-term improvements in BPD symptomatology posttreatment (g = -0.89 [-1.75, -0.02]) but not in follow-up (g = 0.06 [-0.26, 0.39]). There was no significant difference in treatment retention between the experimental and control groups overall (odds ratio [OR] 1.02, 95% confidence interval [CI], 0.92 to 1.12, I2 = 52%). Psychotherapy reduced the frequency of nonsuicidal self-injury (OR = 0.34, 95% CI, 0.16 to 0.74) but not suicide attempts (OR = 1.03, 95% CI, 0.46 to 2.30). CONCLUSIONS: There is a growing variety of psychotherapeutic interventions for adolescents with BPD symptomatology that appears feasible and effective in the short term, but efficacy is not retained in follow-up-particularly for frequency of suicide attempts.


Assuntos
Transtorno da Personalidade Borderline , Comportamento Autodestrutivo , Adolescente , Transtorno da Personalidade Borderline/terapia , Humanos , Psicoterapia , Psicotrópicos , Comportamento Autodestrutivo/terapia
8.
J Am Chem Soc ; 141(50): 19542-19545, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31820965

RESUMO

As a rapid, controllable, and easily transferrable approach to the preparation of antimicrobial nanoparticle systems, a one-step, light-driven procedure was developed to produce asymmetric hybrid inorganic-organic nanoparticles (NPs) directly from a homogeneous Ag/polymer mixture. An amphiphilic triblock polymer was designed and synthesized to build biocompatible NPs, consisting of poly(ethylene oxide) (PEO), carboxylic acid-functionalized polyphosphoester (PPE), and poly(l-lactide) (PLLA). Unexpectedly, snowman-like asymmetric nanostructures were subsequently obtained by simply loading silver cations into the polymeric micelles together with purification via centrifugation. With an understanding of the chemistry of the asymmetric NP formation, a controllable preparation strategy was developed by applying UV irradiation. A morphology transition was observed by transmission electron microscopy over the UV irradiation time, from small silver NPs distributed inside the micelles into snowman-like asymmetric NPs, which hold promise for potential antimicrobial applications with their unique two-stage silver release profiles.


Assuntos
Luz , Nanopartículas/química , Polímeros/química , Prata/química , Processos Fotoquímicos
9.
Mol Pharm ; 16(7): 3178-3187, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31244220

RESUMO

In this study, dinitrosyl iron complexes (DNICs) are shown to deliver nitric oxide (NO) into the cytosol of vascular smooth muscle cells (SMCs), which play a major role in vascular relaxation and contraction. Malfunction of SMCs can lead to hypertension, asthma, and erectile dysfunction, among other disorders. For comparison of the five DNIC derivatives, the following protocols were examined: (a) the Griess assay to detect nitrite (derived from NO conversion) in the absence and presence of SMCs; (b) the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium (MTS) assay for cell viability; (c) an immunotoxicity assay to establish if DNICs stimulate immune response; and (d) a fluorometric assay to detect intracellular NO from treatment with DNICs. Dimeric Roussin's red ester (RRE)-type {Fe(NO)2}9 complexes containing phenylthiolate bridges, [(µ-SPh)Fe(NO)2]2 or SPhRRE, were found to deliver NO with the lowest effect on cell toxicity (i.e., highest IC50). In contrast, the RRE-DNIC with the biocompatible thioglucose moiety, [(µ-SGlu)Fe(NO)2]2 (SGlu = 1-thio-ß-d-glucose tetraacetate) or SGluRRE, delivered a higher concentration of NO to the cytosol of SMCs with a 10-fold decrease in IC50. Additionally, monomeric DNICs stabilized by a bulky N-heterocyclic carbene (NHC), namely, 1,3-bis(2,4,6-trimethylphenyl)imidazolidene (IMes), were synthesized and yielded the DNIC complexes SGluNHC, [IMes(SGlu)Fe(NO)2], and SPhNHC, [IMes(SPh)Fe(NO)2]. These oxidized {Fe(NO)2}9 NHC DNICs have an IC50 of ∼7 µM; however, the NHC-based complexes did not transfer NO into the SMC. Per contra, the reduced, mononuclear {Fe(NO)2}10 neocuproine-based DNIC, neoDNIC, depressed the viability of the SMCs, as well as generated an increase of intracellular NO. Regardless of the coordination environment or oxidation state, all DNICs showed a dinitrosyl iron unit (DNIU)-dependent increase in viability. This study demonstrates a structure-function relationship between the DNIU coordination environment and the efficacy of the DNIC treatments.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Ferro/metabolismo , Ferro/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Óxidos de Nitrogênio/metabolismo , Óxidos de Nitrogênio/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Citosol/metabolismo , Dimerização , Interações Hidrofóbicas e Hidrofílicas , Concentração Inibidora 50 , Ferro/química , Camundongos , Músculo Liso Vascular/citologia , Óxidos de Nitrogênio/química , Oxirredução , Células RAW 264.7 , Ratos , Solubilidade , Água/química
10.
Langmuir ; 35(5): 1503-1512, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30346776

RESUMO

A zwitterionic polyphosphoester (zPPE), specifically l-cysteine-functionalized poly(but-3-yn-1-yloxy)-2-oxo-1,3,2-dioxaphospholane (zPBYP), has been developed as a poly(ethylene glycol) (PEG) alternative coating material for gold nanoparticles (AuNPs), the most extensively investigated metal nanoparticulate platform toward molecular imaging, photothermal therapy, and drug delivery applications. Thiol-yne conjugation of cysteine transformed an initial azido-terminated and alkynyl-functionalized PBYP homopolymer into zPBYP, offering hydrolytic degradability, biocompatibility, and versatile reactive moieties for installation of a range of functional groups. Despite minor degradation during purification, zPPEs were able to stabilize AuNPs presumably through multivalent interactions between combinations of the side chain zwitterions (thioether and phosphoester groups of the zPPEs with the AuNPs). 31P NMR studies in D2O revealed ca. 20% hydrolysis of the phosphoester moieties of the repeat units had occurred during the workup and purification by aqueous dialysis at pH 3 over ca. 1 d, as observed by the 31P signal of the phosphotriesters resonating at ca. -0.5 to -1.7 shifting downfield to ca. 1.1 to -0.4 ppm, attributed to transformation to phosphates. Further hydrolysis of side chain and backbone units proceeded to an extent of ca. 75% over the next 2 d in nanopure water (pH 5-6). The NMR degradation results were consistent with the broadening and red-shift of the surface plasmon resonance (SPR) observed by UV-vis spectroscopy of the zPPE-coated AuNPs in water over time. All AuNP formulations in this study, including those with citrate, PEG, and zPPE coatings, exhibited negligible immunotoxicity, as determined by cytokine overexpression in the presence of the nanostructures relative to those in cell culture medium. Notably, the zPPE-coated AuNPs displayed superior antifouling properties, as assessed by the extent of cytokine adsorption relative to both the PEGylated and citrate-coated AuNPs. Taken together, the physicochemical and biological evaluations of zPPE-coated AuNPs in conjunction with PEGylated and citrate-coated analogues indicate the promise of zPPEs as favorable alternatives to PEG coatings, with negligible immunotoxicity, good antifouling performance, and versatile reactive groups that enable the preparation of highly tailored nanomaterials for diverse applications.


Assuntos
Plásticos Biodegradáveis/química , Materiais Revestidos Biocompatíveis/química , Nanopartículas Metálicas/química , Adsorção , Animais , Plásticos Biodegradáveis/síntese química , Plásticos Biodegradáveis/metabolismo , Incrustação Biológica/prevenção & controle , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/metabolismo , Citocinas/química , Citocinas/metabolismo , Ouro/química , Camundongos , Ligação Proteica , Células RAW 264.7
11.
Biomacromolecules ; 20(1): 109-117, 2019 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-30179461

RESUMO

Magnolol, a neolignan natural product with antioxidant properties, contains inherent, orthogonal, phenolic, and alkenyl reactive groups that were used in both direct thermoset synthesis, as well as the stepwise synthesis of a small library of monomers, followed by transformation into thermoset materials. Each monomer from the small library was prepared via a single step functionalization reaction of the phenolic groups of magnolol. Thermoset materials were realized through solvent-free, thiol-ene reactions, and the resulting cross-linked materials were each comprised of thioether and ester linkages, with one retaining the hydrophilic phenols from magnolol, another having the phenols protected as an acetonide, and two others incorporating the phenols into additional cross-linking sites via hydrolytically labile carbonates or stable ether linkages. With this diversity of chemical compositions and structures, the thermosets displayed a range of thermomechanical properties including glass transition temperatures, Tg, 29-52 °C, onset of thermal degradation, Td, from about 290-360 °C, and ultimate strength up to 50 MPa. These tunable materials were studied in their degradation and biological properties with the aim of exploiting the antioxidant properties of the natural product. Hydrolytic degradation occurred under basic conditions (pH = 11) in all thermosets, but with kinetics that were dependent upon their chemical structures and mechanical properties: 20% mass loss was observed at 5, 7, 27, and 40 weeks for the thermosets produced from magnolol directly, acetonide-protected magnolol, bis(allyl carbonate)-functionalized magnolol, and bis(allyl ether)-functionalized magnolol, respectively. Isolated degradation products and model compounds displayed antioxidant properties similar to magnolol, as determined by both UV-vis and in vitro reactive oxygen species (ROS) assays. As these magnolol-based thermosets were found to also allow for extended cell culture, these materials may serve as promising degradable biomaterials.


Assuntos
Antioxidantes/síntese química , Plásticos Biodegradáveis/síntese química , Compostos de Bifenilo/química , Lignanas/síntese química , Polímeros Responsivos a Estímulos/síntese química , Ácido 3-Mercaptopropiônico/análogos & derivados , Ácido 3-Mercaptopropiônico/química , Animais , Antioxidantes/farmacologia , Bovinos , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Lignanas/química , Fenóis/química , Propilenoglicóis/química , Estresse Mecânico , Temperatura
12.
Int J Eat Disord ; 52(2): 175-182, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30638270

RESUMO

OBJECTIVE: The relationship between eating disorders (EDs) and substance use (SU) has only been briefly described in literature using mainly adult populations. This study examined the prevalence and characteristics of SU among patients of an adolescent ED outpatient treatment program. METHOD: A retrospective chart analysis was conducted to determine and subsequently compare medical status, psychosocial factors, treatment course and outcome between patients with and without SU. RESULTS: Over 60% of patients with SU status (n = 203) reported regularly consuming substances. 33.4% of substance users received a diagnosis involving purging behaviors compared to 5.9% of nonusers. Females composed 96.4% and 81.7% of users and nonusers, respectively. Users reported significantly more self-harm (57.7% of users vs. 38.6% of nonusers) but did not differ significantly in terms of trauma (abuse or victimization; 48.3% of users vs. 44.9% of nonusers). The percentage of ideal body weight significantly improved throughout treatment and did not differ by SU with a mean increase of 5.29% (SD = 13.6) among nonusers compared to 5.45% (SD = 7.5) of users. While users and nonusers did not differ before and after treatment in ED severity, users were more likely than nonusers to drop-out of treatment (41.5% of users vs. 25.2% of nonusers). DISCUSSION: Adolescents with SU benefit from ED outpatient treatment as much as those without SU, however, users are more likely to drop-out. Therefore, treatment should target these adolescents' emotional dysregulation to improve treatment compliance. Further research is necessary to determine the efficacy of such an approach.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adolescente , Transtornos da Alimentação e da Ingestão de Alimentos/patologia , Feminino , Humanos , Masculino , Pacientes Ambulatoriais , Estudos Retrospectivos , Transtornos Relacionados ao Uso de Substâncias/patologia
13.
J Am Chem Soc ; 140(4): 1438-1446, 2018 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-29350522

RESUMO

Although nanomedicines have been pursued for nearly 20 years, fundamental chemical strategies that seek to optimize both the drug and drug carrier together in a concerted effort remain uncommon yet may be powerful. In this work, two block polymers and one dimeric prodrug molecule were designed to be coassembled into degradable, functional nanocarriers, where the chemistry of each component was defined to accomplish important tasks. The result is a poly(ethylene glycol) (PEG)-protected redox-responsive dimeric paclitaxel (diPTX)-loaded cationic poly(d-glucose carbonate) micelle (diPTX@CPGC). These nanostructures showed tunable sizes and surface charges and displayed controlled PTX drug release profiles in the presence of reducing agents, such as glutathione (GSH) and dithiothreitol (DTT), thereby resulting in significant selectivity for killing cancer cells over healthy cells. Compared to free PTX and diPTX, diPTX@CPGC exhibited improved tumor penetration and significant inhibition of tumor cell growth toward osteosarcoma (OS) lung metastases with minimal side effects both in vitro and in vivo, indicating the promise of diPTX@CPGC as optimized anticancer therapeutic agents for treatment of OS lung metastases.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Glucose/química , Glutationa/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/química , Osteossarcoma/tratamento farmacológico , Paclitaxel/farmacologia , Antineoplásicos Fitogênicos/síntese química , Antineoplásicos Fitogênicos/química , Proliferação de Células/efeitos dos fármacos , Dimerização , Ditiotreitol/síntese química , Ditiotreitol/química , Ditiotreitol/farmacologia , Portadores de Fármacos/química , Desenho de Fármacos , Glutationa/síntese química , Glutationa/química , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Conformação Molecular , Osteossarcoma/patologia , Paclitaxel/síntese química , Paclitaxel/química
14.
Biomacromolecules ; 19(4): 1212-1222, 2018 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-29526096

RESUMO

To expand the range of functional polymer materials to include fully hydrolytically degradable systems that bear bioinspired phosphorus-containing linkages both along the backbone and as cationic side chain moieties for packaging and delivery of nucleic acids, phosphonium-functionalized polyphosphoester- block-poly(l-lactide) copolymers of various compositions were synthesized, fully characterized, and their self-assembly into nanoparticles were studied. First, an alkyne-functionalized polyphosphoester- block-poly(l-lactide) copolymer was synthesized via a one pot sequential ring opening polymerization of an alkyne-functionalized phospholane monomer, followed by the addition of l-lactide to grow the second block. Second, the alkynyl side groups of the polyphosphoester block were functionalized via photoinitiated thiol-yne radical addition of a phosphonium-functionalized free thiol. The polymers of varying phosphonium substitution degrees were self-assembled in aqueous buffers to afford formation of well-defined core-shell assemblies with an average size ranging between 30 and 50 nm, as determined by dynamic light scattering. Intracellular delivery of the nanoparticles and their effects on cell viability and capability at enhancing transfection efficiency of nucleic acids (e.g., siRNA) were investigated. Cell viability assays demonstrated limited toxicity of the assembly to RAW 264.7 mouse macrophages, except at high polymer concentrations, where the polymer of high degree of phosphonium functionalization induced relatively higher cytotoxicity. Transfection efficiency was strongly affected by the phosphonium-to-phosphate (P+/P-) ratios of the polymers and siRNA, respectively. The AllStars Hs Cell Death siRNA complexed to the various copolymers at a P+/P- ratio of 10:1 induced comparable cell death to Lipofectamine. These fully degradable nanoparticles might provide biocompatible nanocarriers for therapeutic nucleic acid delivery.


Assuntos
Técnicas de Transferência de Genes , Nanopartículas/química , Compostos Organofosforados/química , Polímeros/química , Alcinos/química , Animais , Dioxanos/química , Macrófagos/efeitos dos fármacos , Camundongos , Nanopartículas/administração & dosagem , Fósforo/química , Polímeros/administração & dosagem , Células RAW 264.7 , Compostos de Sulfidrila/química
15.
Can J Psychiatry ; 63(4): 240-249, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29528720

RESUMO

OBJECTIVE: Children and adolescents with a range of psychiatric disorders are increasingly being prescribed atypical or second-generation antipsychotics (SGAs). While SGAs are effective at treating conduct and behavioural symptoms, they infer significant cardiometabolic risk. This study aims to explore what patient, treatment, and health care utilization variables are associated with adherence to Canadian Alliance for Monitoring Effectiveness and Safety of Antipsychotics in Children (CAMESA) metabolic monitoring guidelines. METHOD: A retrospective chart review of 294 children and adolescents accessing a large outpatient psychiatry setting within a 2-year study period (2014-2016) was conducted. Baseline and follow-up metabolic monitoring, demographic, treatment, and health care utilization variables were then assessed over a 1-year period of interest. RESULTS: Metabolic monitoring practices did not adhere to CAMESA guidelines and were very poor over the 1-year observation period. There were significant differences between children (ages 4-12 years, n = 99) and adolescents (ages 13-18 years, n = 195). In adolescents, factors associated with any baseline metabolic monitoring were a higher number of psychiatry visits (odds ratio [OR], 1.2; 95% confidence interval [CI], 1.10 to 1.41), longer duration of contact (OR, 14; 95% CI, 2.31 to 82.4), and use of other non-SGA medications (OR, 3.2; 95% CI, 1.17 to 8.94). Among children, having an emergency room visit (OR, 3.4; 95% CI, 1.01 to 11.71) and taking aripiprazole (OR, 7.4; 95% CI, 2.02 to 27.45) increased the odds of receiving baseline metabolic monitoring. CONCLUSION: Findings from this study highlight the need for better metabolic monitoring for children and adolescents taking SGAs. Enhanced focus on opportunities for multidisciplinary collaboration is needed to improve the quality of care offered to this population.


Assuntos
Antipsicóticos/efeitos adversos , Monitoramento de Medicamentos/estatística & dados numéricos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/metabolismo , Fidelidade a Diretrizes/estatística & dados numéricos , Transtornos Mentais/tratamento farmacológico , Doenças Metabólicas/induzido quimicamente , Doenças Metabólicas/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino
16.
Ophthalmology ; 123(7): 1458-68, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27089999

RESUMO

PURPOSE: To validate the Ocular Pain Assessment Survey (OPAS), specifically designed to measure ocular pain and quality of life for use by eye care practitioners and researchers. DESIGN: A single-center cohort study was conducted among patients with and without corneal and ocular surface pain at initial and follow-up visits over a 6-month period. The content of the OPAS was guided by literature review, a body of experts, and incorporating conceptual frameworks from existing pain questionnaires. The Wong-Baker FACES Pain Rating Scale served as the gold standard for measuring the intensity of ocular pain. PARTICIPANTS: A total of 102 patients aged 18 to 80 years completed the OPAS at the initial visit. A total of 21 patients were followed up after treatment. METHODS: Indices of validity and internal consistency (Spearman's rank-order, rs, or Pearson's correlation coefficients, rp), and coefficient of reliability (Cronbach's α) were determined in addition to equivalence testing, exploratory factor analysis (EFA), and diagnostic analysis. MAIN OUTCOME MEASURES: Eye pain intensity was the primary outcome measure, and interference with quality of life (QoL), aggravating factors, associated factors, associated non-eye pain intensity, and self-reported symptomatic relief were the secondary outcome measures. RESULTS: The OPAS had criterion validity at both initial (rs = 0.71; n = 102; P < 0.01) and follow-up visits (rs = 0.97; n = 21; P < 0.01). Equivalence tests yielded OPAS and gold standard equivalence for both the initial and follow-up visits. The EFA supported 6 subscales (eye pain intensity at 24 hours and 2 weeks, non-eye pain intensity, QoL, aggravating factors, and associated factors) confirming multidimensionality. Cronbach's α >0.83 for all subscales established strong internal consistency, which correlated with the gold standard, including 24-hour eye pain intensity and QoL interference scores (rp = 0.81, 0.64, respectively P < 0.001). At follow-up, reduction in pain scores was accompanied by improvement in all dimensions of the OPAS. Percentage change in QoL correlated to percentage change in the gold standard (rp = 0.53; P < 0.05). The OPAS was sensitive (94%), specific (81%), and accurate (91%), with a diagnostic odds ratio >50. CONCLUSIONS: The OPAS is a valid, reliable, and responsive tool with strong psychometric and diagnostic properties in the multidimensional quantification of corneal and ocular surface pain intensity, and QoL.


Assuntos
Dor Ocular/diagnóstico , Medição da Dor/métodos , Inquéritos e Questionários/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças da Córnea/diagnóstico , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/normas , Psicometria/normas , Qualidade de Vida , Reprodutibilidade dos Testes , Adulto Jovem
19.
J Pak Med Assoc ; 65(4): 366-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25976568

RESUMO

OBJECTIVE: To estimate the prevalence of Chronic Kidney Disease in an urban city and to assess the risk factors associated with the condition. METHODS: The cross-sectional study was carried out from June to December 2012 by arranging health camps for asymptomatic population in Karachi at busy shopping areas frequented by people of all socioeconomic classes. The camps provided free screening tests for the general public. Serum creatinine was checked and estimated Glomerular Filtration Rate was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation. SPSS 17 was used for statistical analysis. RESULTS: Of the 301 subjects who came to the camps, 293(97%) had their serum creatinine checked. The age range was 30-80 years. Chronic Kidney Disease was found in 75(25.60%)subjects. A significant relationship was found between the disease and Diabetes Mellitus and Hypertension (p=0.006). There was also a significant relationship between Hypertension and Diabetes with mean Glomerular Filtration Rate (p<0.001). CONCLUSIONS: In view of the prevalence rate of Chronic Kidney Disease, early screening and risk factor stratification is recommended.


Assuntos
Efeitos Psicossociais da Doença , Diabetes Mellitus/epidemiologia , Hipertensão/epidemiologia , Insuficiência Renal Crônica , Adulto , Idoso , Creatinina/sangue , Estudos Transversais , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Prevalência , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Fatores de Risco , Fatores Socioeconômicos
20.
ACG Case Rep J ; 11(4): e01327, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38586821

RESUMO

Hepatitis B virus (HBV) reactivation can occur with the use of immunosuppressive therapy used to treat autoimmune conditions, such as rheumatoid arthritis. Janus kinase inhibitors, such as upadacitinib, have been approved for the treatment of rheumatoid arthritis. This is the first case report of a patient who used upadacitinib without antiviral prophylaxis against HBV and developed HBV reactivation, leading to fulminant hepatic failure necessitating emergent liver transplantation.

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