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Cochlear implants (CIs) are neuroprosthetic devices that can provide hearing to deaf people1. Despite the benefits offered by CIs, the time taken for hearing to be restored and perceptual accuracy after long-term CI use remain highly variable2,3. CI use is believed to require neuroplasticity in the central auditory system, and differential engagement of neuroplastic mechanisms might contribute to the variability in outcomes4-7. Despite extensive studies on how CIs activate the auditory system4,8-12, the understanding of CI-related neuroplasticity remains limited. One potent factor enabling plasticity is the neuromodulator noradrenaline from the brainstem locus coeruleus (LC). Here we examine behavioural responses and neural activity in LC and auditory cortex of deafened rats fitted with multi-channel CIs. The rats were trained on a reward-based auditory task, and showed considerable individual differences of learning rates and maximum performance. LC photometry predicted when CI subjects began responding to sounds and longer-term perceptual accuracy. Optogenetic LC stimulation produced faster learning and higher long-term accuracy. Auditory cortical responses to CI stimulation reflected behavioural performance, with enhanced responses to rewarded stimuli and decreased distinction between unrewarded stimuli. Adequate engagement of central neuromodulatory systems is thus a potential clinically relevant target for optimizing neuroprosthetic device use.
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Implantes Cocleares , Surdez , Locus Cerúleo , Animais , Ratos , Implante Coclear , Surdez/fisiopatologia , Surdez/terapia , Audição/fisiologia , Aprendizagem/fisiologia , Locus Cerúleo/citologia , Locus Cerúleo/fisiologia , Plasticidade Neuronal , Norepinefrina/metabolismo , Córtex Auditivo/citologia , Córtex Auditivo/fisiologia , Córtex Auditivo/fisiopatologia , Neurônios/fisiologia , Recompensa , Optogenética , FotometriaRESUMO
OBJECTIVE: To uncover the values and preferences of the caregivers for children with medical complexity (CMC), using the test case of surgical treatment decision-making for pediatric neuromuscular scoliosis (NMS) that will inform the future development of a decision support tool in this population. STUDY DESIGN: We conducted a qualitative study of semi-structured interviews of English- and Spanish-speaking caregivers of children with NMS from two geographically distinct children's hospitals. We used purposive sampling of language and treatment options selected to capture diverse experiences. Analysis was based on grounded theory with synthesized caregiver values and preferences themes. RESULTS: From 47 participants, we completed 41 interviews (9 in Spanish). Caregivers had a mean age of 43.2 years, were mostly White (66%), and had children with a mean age of 15.6. 64% chose surgery. The following values and preferences were important to many caregivers: reducing scoliosis-related pain, minimizing mobility limitations to optimize socio-emotional quality of life, limiting the impact of comorbidities on overall quality of life, information provided by peer support, the uncertainty of outcomes due to underlying comorbidities, and the uncertainty related to the anticipated progression of their child's scoliosis curve. Caregivers experienced immense uncertainty related to treatment outcomes due to their child's comorbidities. CONCLUSIONS: Caregivers of CMC may benefit from decision support that includes both values clarification exercises to help caregivers identify what of the many possible values and preferences are important to them and novel methods to communicate uncertainty in the care of CMC.
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Incorporation of external information is becoming increasingly common when designing clinical trials. Availability of multiple sources of information has inspired the development of methodologies that account for potential heterogeneity not only between the prospective trial and the pooled external data sources but also between the different external data sources themselves. Our approach proposes an intuitive way of handling such a scenario for the continuous outcomes setting by using propensity score-based stratification and then utilizing robust meta-analytic predictive priors for each stratum to incorporate the prior data to distinguish among different external data sources in each stratum. Through extensive simulations, our approach proves to be more efficient and less biased than the currently available methods. A real case study using clinical trials that study schizophrenia from multiple different sources is also included.
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Pontuação de Propensão , Humanos , Estudos Prospectivos , Ensaios Clínicos como AssuntoRESUMO
Cluster-randomized trials (CRTs) involve randomizing entire groups of participants-called clusters-to treatment arms but are often comprised of a limited or fixed number of available clusters. While covariate adjustment can account for chance imbalances between treatment arms and increase statistical efficiency in individually randomized trials, analytical methods for individual-level covariate adjustment in small CRTs have received little attention to date. In this paper, we systematically investigate, through extensive simulations, the operating characteristics of propensity score weighting and multivariable regression as two individual-level covariate adjustment strategies for estimating the participant-average causal effect in small CRTs with a rare binary outcome and identify scenarios where each adjustment strategy has a relative efficiency advantage over the other to make practical recommendations. We also examine the finite-sample performance of the bias-corrected sandwich variance estimators associated with propensity score weighting and multivariable regression for quantifying the uncertainty in estimating the participant-average treatment effect. To illustrate the methods for individual-level covariate adjustment, we reanalyze a recent CRT testing a sedation protocol in 31 pediatric intensive care units.
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Simulação por Computador , Criança , Humanos , Análise por Conglomerados , Ensaios Clínicos Controlados Aleatórios como Assunto , Tamanho da Amostra , ViésRESUMO
Genetic variation among inhaled corticosteroid (ICS)-metabolizing enzymes may affect asthma control, but evidence is limited. This study tested the hypothesis that single-nucleotide polymorphisms (SNPs) in Cytochrome P450 3A5 (CYP3A5) would affect asthma outcomes. Patients aged 2-18 years with persistent asthma were recruited to use the electronic AsthmaTracker (e-AT), a self-monitoring tool that records weekly asthma control, medication use, and asthma outcomes. A subset of patients provided saliva samples for SNP analysis and participated in a pharmacokinetic study. Multivariable regression analysis adjusted for age, sex, race, and ethnicity was used to evaluate the impact of CYP3A5 SNPs on asthma outcomes, including asthma control (measured using the asthma symptom tracker, a modified version of the asthma control test or ACT), exacerbations, and hospital admissions. Plasma corticosteroid and cortisol concentrations post-ICS dosing were also assayed using liquid chromatography-tandem mass spectrometry. Of the 751 patients using the e-AT, 166 (22.1%) provided saliva samples and 16 completed the PK study. The e-AT cohort was 65.1% male, and 89.6% White, 6.0% Native Hawaiian, 1.2% Black, 1.2% Native American, 1.8% of unknown race, and 15.7% Hispanic/Latino; the median age was 8.35 (IQR: 5.51-11.3) years. CYP3A5*3/*3 frequency was 75.8% in White subjects, 50% in Native Hawaiians and 76.9% in Hispanic/Latino subjects. Compared with CYP3A5*3/*3, the CYP3A5*1/*x genotype was associated with reduced weekly asthma control (OR: 0.98; 95% CI: 0.97-0.98; p < 0.001), increased exacerbations (OR: 6.43; 95% CI: 4.56-9.07; p < 0.001), and increased asthma hospitalizations (OR: 1.66; 95% CI: 1.43-1.93; p < 0.001); analysis of 3/*3, *1/*1 and *1/*3 separately showed an allelic copy effect. Finally, PK analysis post-ICS dosing suggested muted changes in cortisol concentrations for patients with the CYP3A5*3/*3 genotype, as opposed to an effect on ICS PK. Detection of CYP3A5*3/3, CYPA35*1/*3, and CYP3A5*1/*1 could impact inhaled steroid treatment strategies for asthma in the future.
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Corticosteroides , Asma , Citocromo P-450 CYP3A , Polimorfismo de Nucleotídeo Único , Humanos , Asma/tratamento farmacológico , Asma/genética , Criança , Masculino , Feminino , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Adolescente , Pré-Escolar , Corticosteroides/uso terapêutico , Corticosteroides/farmacocinética , Corticosteroides/administração & dosagem , Genótipo , Hidrocortisona/sangue , Saliva/metabolismo , Resultado do TratamentoRESUMO
Ribosomally synthesized and post-translationally modified peptides (RiPPs) are a large and diverse class of natural products of ribosomal origin. In the past decade, various sophisticated machine-learning-based software packages have been established to discover novel RiPPs that do not resemble the known families. Here, we show that tailoring enzymes that cluster with various RiPP families can serve as effective bioinformatic seeds, providing a complementary approach for novel RiPP discovery. Leveraging the fact that O-methyltransferases homologous to protein isoaspartyl methyltransferases (PIMTs) are associated with lasso peptide, graspetide, and lanthipeptide biosynthetic gene clusters (BGCs), we utilized a C-terminal motif unique to RiPP-associated O-methyltransferases as the search query to discover a novel family of RiPPs, the imiditides. Our genome-mining algorithm reveals a total of 670 imiditide BGCs, distributed across Gram-positive bacterial genomes. In addition, we demonstrate the heterologous production of the founding member of the imiditide family, mNmaAM, encoded in the genome of Nonomuraea maritima. In contrast to other RiPP-associated PIMTs that recognize constrained peptides as substrates, the PIMT homologue in the mNmaAM BGC, NmaM, methylates a specific Asp residue on the linear precursor peptide, NmaA. The methyl ester is then turned into an aspartimide spontaneously. Substrate specificity is achieved by extensive charge-charge interactions between the precursor NmaA and the modifying enzyme NmaM suggested by both experiments and an AlphaFold model prediction. Our study shows that PIMT-mediated aspartimide formation is an emerging backbone modification strategy in the biosynthesis of multiple RiPP families.
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Algoritmos , Produtos Biológicos , Ácido Aspártico , MetiltransferasesRESUMO
In observational studies, causal inference relies on several key identifying assumptions. One identifiability condition is the positivity assumption, which requires the probability of treatment be bounded away from 0 and 1. That is, for every covariate combination, it should be possible to observe both treated and control subjects the covariate distributions should overlap between treatment arms. If the positivity assumption is violated, population-level causal inference necessarily involves some extrapolation. Ideally, a greater amount of uncertainty about the causal effect estimate should be reflected in such situations. With that goal in mind, we construct a Gaussian process model for estimating treatment effects in the presence of practical violations of positivity. Advantages of our method include minimal distributional assumptions, a cohesive model for estimating treatment effects, and more uncertainty associated with areas in the covariate space where there is less overlap. We assess the performance of our approach with respect to bias and efficiency using simulation studies. The method is then applied to a study of critically ill female patients to examine the effect of undergoing right heart catheterization.
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Modelos Estatísticos , Humanos , Feminino , Probabilidade , Simulação por Computador , ViésRESUMO
Tricuspid regurgitation is a widely recognised phenomenon in patients with transvenous cardiac rhythm management (CRM) devices. If tricuspid valve repair or replacement is to be considered, what to do with the existing CRM system requires scrutiny with multidisciplinary input. We present a case of multifactorial tricuspid regurgitation in a 48-year-old female with giant cell myocarditis and a transvenous implantable cardioverter-defibrillator (ICD). Key considerations in management and alternative CRM options are discussed.
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Desfibriladores Implantáveis , Miocardite , Insuficiência da Valva Tricúspide , Feminino , Humanos , Pessoa de Meia-Idade , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/cirurgia , PacientesRESUMO
Agricultural non-point source (ANPS) pollution is a pressing environmental issue in developing countries that poses a substantial threat to sustainable development. With the rapid growth of e-commerce and its great penetration and transformation in many socioeconomic sectors, e-commerce plus agriculture is widely regarded as the solution to sustainable agricultural development. However, the environmental impacts of e-commerce on agriculture, as well as the underlying mechanisms have yet to be fully explored and verified. Based on China's practices of e-commerce development and its integration with agriculture, a panel dataset of 283 prefecture-level cities from 2009 to 2019 was collected, and a spatial difference in difference (SDID) model combined with a Durbin model was constructed to examine the local and spatial spillover effects of e-commerce development on ANPS pollution. It is found out that e-commerce development has significant positive environmental impacts achieved by stimulating industrial structure upgrading and promoting green technology innovation, while the mechanism of cultivation scaling up tends to aggravate the ANPS pollution. Spatial analysis demonstrates that e-commerce development also helps alleviate the ANPS pollution of neighboring regions with a decayed effect over a distance. Meanwhile, the impact of e-commerce on mitigating ANPS pollution shows regional heterogeneity. Those developed regions present significant positive effects, while those regions dominated by agriculture economy and without sufficient supporting facilities for e-commerce development, show significant negative effects. Therefore, we argue that the positive environmental contribution of e-commerce is not bound to happen but instead is contingent, while policies should be adapted to local conditions and enhanced to encourage the integration of e-commerce and other socioeconomic sectors, in order to develop beyond the immature pioneering stage.
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Poluição Difusa , Cidades , Agricultura , Comércio , China , Desenvolvimento Econômico , Poluição Ambiental/prevenção & controleRESUMO
Implantation of subcutaneous implantable cardioverter-defibrillator in a patient with existing unipolar pacemaker is against manufacturer recommendations. We report the case of a successful subcutaneous implantable cardioverter-defibrillator implantation in a patient with Fontan circulation and concomitant active unipolar pacing and present a summary of recommendations when considering subcutaneous implantable cardioverter-defibrillator implantation with unipolar pacing. Recommendations included: pre-procedure screening, rescreening during implantation and ventricular fibrillation induction, pacemaker programming, and post-procedure investigations.
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Ultraviolet radiation (UVR) exposure is a primary risk factor for the development of melanoma. However, adults and adolescents often do not engage in preventive behaviors to reduce UVR exposure. Rural residents may be at higher risk for melanoma due to lower use of sun protection strategies, which increases their overall UVR exposure compared to those who live in urban areas. The purpose of this study was to evaluate differences in UVR exposure between rural and urban residents in a geographic area with high incidence of melanoma. Children (aged 8-17 years) and adults (≥ 18 years) from rural and urban areas of Utah were asked to wear a UVR monitoring device for 14 days. The sample included 97 children and 97 adults. Data was collected from June to October 2018. Non-parametric Mann-Whitney tests and quantile regression were used to compare UVR exposure levels between urban and rural participants, separately for adults and children. For adults, rural residence significantly increased total UVR dose ( ß: 24.6; 95% CI 3.75, 42.74) and the UVR dose during peak UVR hours among participants with the highest UVR doses (ß: 16.3; 95% CI 17.4, 24.63). Rural children exhibited significantly higher UVR doses for peak UVR hours for the entire study period (ß: 4.14; 95% CI 0.83, 7.46) and on weekdays (ß: 0.39; 95% CI 0.05, 0.73). The findings from this study indicate that rural residents may receive higher levels of UVR exposure than urban residents, and that prevention efforts could be tailored to address these geographical differences.
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Melanoma/prevenção & controle , População Rural/estatística & dados numéricos , Neoplasias Cutâneas/prevenção & controle , Raios Ultravioleta/efeitos adversos , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Criança , Humanos , Incidência , Masculino , Fatores de Risco , UtahRESUMO
The promotion of axonal regeneration is required for functional recovery from stroke and various neuronal injuries. However, axonal regeneration is inhibited by diverse axonal growth inhibitors, such as Nogo-A. Nogo-66, a C-terminal domain of Nogo-A, binds to the Nogo-A receptor 1 (NgR1) and induces the collapse of growth cones and inhibits neurite outgrowth. NgR1 is also a receptor for additional axonal growth inhibitors, suggesting it is an important target for the prevention of axonal growth inhibition. By using the indirect immunofluorescence method, we show for the first time that a cell-permeable cAMP analog (dibutyryl-cAMP) induced a rapid decrease in the cell surface expression of NgR1 in Neuroscreen-1 (NS-1) cells. The biotinylation method revealed that cAMP indeed induced internalization of NgR1 within minutes. Other intracellular cAMP-elevating agents, such as forskolin, which directly activates adenylyl cyclase, and rolipram, which inhibits cyclic nucleotide phosphodiesterase, also induced this process. This internalization was found to be reversible and influenced by intracellular levels of cAMP. Using selective activators and inhibitors of protein kinase A (PKA) and the exchange protein directly activated by cAMP (Epac), we found that NgR1 internalization is independent of PKA, but dependent on Epac. The decrease in cell surface expression of NgR1 desensitized NS-1 cells to Nogo-66-induced growth cone collapse. Therefore, it is likely that besides axonal growth inhibitors affecting neurons, neurons themselves also self-regulate their sensitivity to axonal growth inhibitors, as influenced by intracellular cAMP/Epac. This normal cellular regulatory mechanism may be pharmacologically exploited to overcome axonal growth inhibitors, and enhance functional recovery after stroke and neuronal injuries.
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AMP Cíclico/metabolismo , Cones de Crescimento/metabolismo , Neurônios/metabolismo , Proteínas Nogo/metabolismo , Receptor Nogo 1/metabolismo , Animais , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Neurônios/citologia , Células PC12 , Transporte Proteico , RatosRESUMO
Melanoma is the deadliest form of skin cancer. Screening can aid in early disease detection, when treatment is more effective. Although there are currently no consensus guidelines regarding skin screening for pediatric populations with elevated familial risk for melanoma, at-risk children with the help of their parents and healthcare providers may implement skin self-exams. Healthcare providers may also recommend screening practices for these children. The goal of the current study was to describe current screening behaviors and provider recommendation for screening among children of melanoma survivors. Parents of children with a family history of melanoma completed a questionnaire that included items on children's screening frequency, thoroughness, and who performed the screening. Seventy-four percent of parents reported that their children (mean age = 9.0 years, SD = 4.8) had engaged in parent-assisted skin self-exams (SSEs) in the past 6 months. Only 12% of parents reported that children received SSEs once per month (the recommended frequency for adult melanoma survivors). In open-ended responses, parents reported that healthcare providers had provided recommendations around how to conduct SSEs, but most parents did not report receiving information on recommended SSE frequency. Twenty-six percent of parents (n = 18) reported that children had received a skin exam by a healthcare provider in the past 6 months. The majority of children with a family history of melanoma are reportedly engaging in skin exams despite the lack of guidelines on screening in this population. Future melanoma preventive interventions should consider providing families guidance about implementing screening with their children.
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Sobreviventes de Câncer/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Anamnese/estatística & dados numéricos , Melanoma/prevenção & controle , Pais/educação , Educação de Pacientes como Assunto , Neoplasias Cutâneas/prevenção & controle , Adolescente , Adulto , Sobreviventes de Câncer/psicologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto JovemRESUMO
PURPOSE: The purpose of the current study was to evaluate differences in reported use of sun protection, tanning behaviors, skin cancer-related knowledge, and perceived risk between rural and urban high school students in a geographic area with high rates of melanoma. METHODS: A total of 1,570 high school students (56.8% female) from urban (6 schools) and rural (7 schools) geographic areas in Utah completed questionnaires assessing sun protection and tanning behaviors, skin cancer-related knowledge, and perceived risk for skin cancer. Analyses examined potential differences in these outcomes between rural and urban students and by gender. RESULTS: Compared to students in urban areas, those in rural areas had lower odds of wearing sunscreen (OR 0.71; 95% CI 0.53, 0.95; p = 0.022), re-applying sunscreen (OR 0.61; 95% CI 0.74, 1.02; p = 0.002), wearing long-sleeved shirts (OR 0.63 95% CI 0.46, 0.86; p = 0.004), and seeking shade (OR 0.67; 95% CI 0.50, 0.88; p = 0.005). CONCLUSIONS: Rural students reported less adequate use of sun protection than urban students. Rural male students reported lower knowledge scores compared to urban males. Future skin cancer prevention efforts targeting rural high schoolers are warranted.
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Conhecimentos, Atitudes e Prática em Saúde , População Rural , Neoplasias Cutâneas/prevenção & controle , Neoplasias Cutâneas/psicologia , Estudantes/psicologia , População Urbana , Adolescente , Feminino , Humanos , Masculino , Risco , Instituições Acadêmicas , Banho de Sol , Protetores Solares/administração & dosagem , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Floppy eyelid syndrome is a disorder in which the tarsal plate is easily distensible and is currently treated with conservative or surgical measures. Human tarsal plate contains type I collagen, which is crosslinked in corneal tissue as a treatment for keratoconus. We hypothesized that collagen crosslinking would similarly stiffen tarsal plate tissue and investigated this in porcine and human tarsal plate specimens. METHODS: Riboflavin-sensitized porcine and human tarsus samples were irradiated with ultraviolet-A light. Porcine experiments were analyzed with gross photographs, anterior segment optical computed tomography (AS-OCT) imaging, and tensile testing. A prospective study of human tarsus was performed on samples from patients undergoing wedge resection for floppy eyelid syndrome and was analyzed with AS-OCT and tensile testing. RESULTS: 73 porcine adnexa and 9 patients (16 eyelids) who underwent wedge excision were included in the study. Grossly, greater stiffness was observed in crosslinked porcine tissue. AS-OCT imaging in porcine tissue showed a distinct hyperreflective band in crosslinked specimens whose area and intensity increased with longer treatment time (P = 0.003); this band was also visible in crosslinked human specimens. Tensile testing was performed, but results were not statistically significant. CONCLUSIONS: AS-OCT imaging, which has not been previously described for tarsal plate, showed a characteristic change in crosslinked porcine and human specimens. Tissue stiffness was increased grossly, but changes in tensile properties were not statistically significant. Further study is warranted to determine relevance as a potential treatment for floppy eyelid syndrome.
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Colágeno Tipo I/metabolismo , Reagentes de Ligações Cruzadas , Doenças Palpebrais/tratamento farmacológico , Pálpebras/metabolismo , Fármacos Fotossensibilizantes/uso terapêutico , Riboflavina/uso terapêutico , Adulto , Animais , Doenças Palpebrais/diagnóstico por imagem , Doenças Palpebrais/metabolismo , Pálpebras/diagnóstico por imagem , Humanos , Estudos Prospectivos , Suínos , Resistência à Tração , Tomografia de Coerência Óptica , Raios UltravioletaRESUMO
OBJECTIVES: To translate and validate the Zurich Chronic Middle Ear Inventory (ZCMEI-21) for the English language in order to provide an English instrument to assess health-related quality of life in chronic otitis media (COM). DESIGN: Pilot translation study including cognitive debriefings, prospective multicentre cross-sectional psychometric validation study. SETTING: Four tertiary referral centres in three different English-speaking countries (UK, USA and Australia). PARTICIPANTS: Adult patients suffering from COM. MAIN OUTCOME MEASURES: The English translation of the ZCMEI-21 (ZCMEI-21-E) and the five-level version of the EQ-5D questionnaire. The EQ-5D, which constitutes a generic measure of health-related quality of life, consists of a descriptive system score and a visual analogue scale. Statistical outcomes included single-item descriptive statistics, internal consistency (Cronbach's α) as an indicator of reliability, as well as construct validity. RESULTS: A total of 124 patients suffering from COM were included. The mean age was 50.1 years (SD 16.9 years), and 72 (58.1%) were males. The Cronbach's α of the ZCMEI-21-E was 0.91, suggesting an excellent internal consistency. The Spearman's correlation coefficient of the ZCMEI-21-E total score was 0.55 (P < 0.0001) for convergent construct validity with EQ-5D descriptive system score and 0.57 (P < 0.0001) with the EQ-5D visual analogue scale. CONCLUSIONS: The ZCMEI-21-E is a new validated questionnaire that provides clinicians with a short, comprehensive and reliable instrument to quantify health-related quality of life in patients suffering from COM. The ZCMEI-21-E may be of use in clinical routine as well as in outcome research and monitoring.
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Idioma , Otite Média/psicologia , Psicometria/métodos , Qualidade de Vida , Traduções , Doença Crônica , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Inquéritos e QuestionáriosRESUMO
A reservoir that could be remotely triggered to release a drug would enable the patient or physician to achieve on-demand, reproducible, repeated, and tunable dosing. Such a device would allow precise adjustment of dosage to desired effect, with a consequent minimization of toxicity, and could obviate repeated drug administrations or device implantations, enhancing patient compliance. It should exhibit low off-state leakage to minimize basal effects, and tunable on-state release profiles that could be adjusted from pulsatile to sustained in real time. Despite the clear clinical need for a device that meets these criteria, none has been reported to date to our knowledge. To address this deficiency, we developed an implantable reservoir capped by a nanocomposite membrane whose permeability was modulated by irradiation with a near-infrared laser. Irradiated devices could exhibit sustained on-state drug release for at least 3 h, and could reproducibly deliver short pulses over at least 10 cycles, with an on/off ratio of 30. Devices containing aspart, a fast-acting insulin analog, could achieve glycemic control after s.c. implantation in diabetic rats, with reproducible dosing controlled by the intensity and timing of irradiation over a 2-wk period. These devices can be loaded with a wide range of drug types, and therefore represent a platform technology that might be used to address a wide variety of clinical indications.
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Sistemas de Liberação de Medicamentos , Raios Infravermelhos , Animais , Desenho de Equipamento , Microscopia Eletrônica de Transmissão , Nanocompostos , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos TestesRESUMO
Fuchs endothelial corneal dystrophy (FECD) is a genetically heterogeneous disease. Hypothesizing that cellular senescence may be relevant in FECD pathogenesis, genetically undifferentiated late-onset FECD endothelial samples were analyzed to identify common changes of specific senescence-related transcripts. Total RNA was extracted from 21 FECD endothelial samples retrieved from patients undergoing lamellar keratoplasty due to clinically diagnosed end-stage FECD and from 12 endothelial samples retrieved from normal autopsy eyes. Taqman low density array (TLDA) cards were used to analyze differential expression of 89 cellular senescence-related transcripts. Result validation was performed using individual real-time PCR assays. TLDA-analysis demonstrated differential expression of 31 transcripts (fold-change >1.5; p < 0.05). Thereof, 27 showed significant up-regulation and 4 significant down-regulation. Markedly elevated mRNA-levels of the constitutively active and reactive oxygen species-generating enzyme NOX4 were found in all evaluable FECD samples. In addition, increased expression of CDKN2A and its transcriptional activators ETS1 and ARHGAP18 (SENEX) along with decreased expression of CDKN2A inhibitor ID1 were detected in FECD samples. Consistent over-expression of NOX4 in FECD endothelial samples suggests a role as pathogenic factor and as a potential new treatment target in FECD. Transcriptional up-regulation of the CDKN2A-pathway provides further evidence for increased cellular senescence in FECD endothelium.
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Apoptose , Senescência Celular , Endotélio Corneano/metabolismo , Proteínas do Olho/genética , Distrofia Endotelial de Fuchs , Regulação da Expressão Gênica , RNA Mensageiro/genética , Endotélio Corneano/patologia , Proteínas do Olho/biossíntese , Distrofia Endotelial de Fuchs/genética , Distrofia Endotelial de Fuchs/metabolismo , Distrofia Endotelial de Fuchs/patologia , Humanos , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Introduction: The application of artificial intelligence (AI) systems in ophthalmology is rapidly expanding. Early detection and management of keratoconus is important for preventing disease progression and the need for corneal transplant. We review studies regarding the utility of AI in the diagnosis and management of keratoconus and other corneal ectasias. Methods: We conducted a systematic search for relevant original, English-language research studies in the PubMed, Web of Science, Embase, and Cochrane databases from inception to October 31, 2023, using a combination of the following keywords: artificial intelligence, deep learning, machine learning, keratoconus, and corneal ectasia. Case reports, literature reviews, conference proceedings, and editorials were excluded. We extracted the following data from each eligible study: type of AI, input used for training, output, ground truth or reference, dataset size, availability of algorithm/model, availability of dataset, and major study findings. Results: Ninety-three original research studies were included in this review, with the date of publication ranging from 1994 to 2023. The majority of studies were regarding the use of AI in detecting keratoconus or subclinical keratoconus (n=61). Among studies regarding keratoconus diagnosis, the most common inputs were corneal topography, Scheimpflug-based corneal tomography, and anterior segment-optical coherence tomography. This review also summarized 16 original research studies regarding AI-based assessment of severity and clinical features, 7 studies regarding the prediction of disease progression, and 6 studies regarding the characterization of treatment response. There were only three studies regarding the use of AI in identifying susceptibility genes involved in the etiology and pathogenesis of keratoconus. Discussion: Algorithms trained on Scheimpflug-based tomography seem promising tools for the early diagnosis of keratoconus that can be particularly applied in low-resource communities. Future studies could investigate the application of AI models trained on multimodal patient information for staging keratoconus severity and tracking disease progression.
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Vernal keratoconjunctivitis (VKC) is a chronic, progressive, allergic ocular surface disorder that can lead to sight-threatening complications. VKC occurs primarily in children and generally resolves about the time of puberty; however, case series and retrospective analyses indicate that approximately 10% of patients with VKC are adults, and that a subset of adult cases develop after puberty. Consequently, two age-related variants of VKC have recently been described: early-onset VKC-which manifests during childhood and persists into adult life-and late-onset disease, which emerges de novo after puberty. Although the signs and symptoms of adult and childhood VKC are similar, adult VKC is a long-lasting disease characterized by severe inflammation and increased risk of conjunctival fibrosis, which may place adult patients at higher risk for sight-threatening complications and adverse impacts on daily life. This review discusses the epidemiology, signs, symptoms, immunopathogenesis of adult VKC variants, and highlights current gaps in research and management of patients with this condition.