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1.
Ann Neurol ; 94(1): 146-159, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36966460

RESUMO

OBJECTIVE: To characterize neurologic manifestations in post-hospitalization Neuro-PASC (PNP) and non-hospitalized Neuro-PASC (NNP) patients. METHODS: Prospective study of the first 100 consecutive PNP and 500 NNP patients evaluated at a Neuro-COVID-19 clinic between 5/2020 and 8/2021. RESULTS: PNP were older than NNP patients (mean 53.9 vs 44.9 y; p < 0.0001) with a higher prevalence of pre-existing comorbidities. An average 6.8 months from onset, the main neurologic symptoms were "brain fog" (81.2%), headache (70.3%), and dizziness (49.5%) with only anosmia, dysgeusia and myalgias being more frequent in the NNP compared to the PNP group (59 vs 39%, 57.6 vs 39% and 50.4 vs 33%, all p < 0.003). Moreover, 85.8% of patients experienced fatigue. PNP more frequently had an abnormal neurologic exam than NNP patients (62.2 vs 37%, p < 0.0001). Both groups had impaired quality of life in cognitive, fatigue, sleep, anxiety, and depression domains. PNP patients performed worse on processing speed, attention, and working memory tasks than NNP patients (T-score 41.5 vs 55, 42.5 vs 47 and 45.5 vs 49, all p < 0.001) and a US normative population. NNP patients had lower results in attention task only. Subjective impression of cognitive ability correlated with cognitive test results in NNP but not in PNP patients. INTERPRETATION: PNP and NNP patients both experience persistent neurologic symptoms affecting their quality of life. However, they harbor significant differences in demographics, comorbidities, neurologic symptoms and findings, as well as pattern of cognitive dysfunction. Such differences suggest distinct etiologies of Neuro-PASC in these populations warranting targeted interventions. ANN NEUROL 2023;94:146-159.


Assuntos
COVID-19 , Síndrome de COVID-19 Pós-Aguda , Humanos , COVID-19/complicações , Estudos Prospectivos , Qualidade de Vida , Fadiga/etiologia
2.
Mol Pharm ; 21(7): 3566-3576, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38899552

RESUMO

Oxidative stress is pivotal in retinal disease progression, causing dysfunction in various retinal components. An effective antioxidant, such as probucol (PB), is vital to counteract oxidative stress and emerges as a potential candidate for treating retinal degeneration. However, the challenges associated with delivering lipophilic drugs such as PB to the posterior segment of the eye, specifically targeting photoreceptor cells, necessitate innovative solutions. This study uses formulation-based spray dry encapsulation technology to develop polymer-based PB-lithocholic acid (LCA) nanoparticles and assesses their efficacy in the 661W photoreceptor-like cell line. Incorporating LCA enhances nanoparticles' biological efficacy without compromising PB stability. In vitro studies demonstrate that PB-LCA nanoparticles prevent reactive oxygen species (ROS)-induced oxidative stress by improving cellular viability through the nuclear erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway. These findings propose PB-LCA nanoparticles as a promising therapeutic strategy for oxidative stress-induced retinopathies.


Assuntos
Antioxidantes , Ácido Litocólico , Nanopartículas , Estresse Oxidativo , Polímeros , Probucol , Espécies Reativas de Oxigênio , Probucol/farmacologia , Probucol/administração & dosagem , Probucol/química , Estresse Oxidativo/efeitos dos fármacos , Nanopartículas/química , Espécies Reativas de Oxigênio/metabolismo , Ácido Litocólico/química , Ácido Litocólico/farmacologia , Animais , Polímeros/química , Linhagem Celular , Antioxidantes/farmacologia , Antioxidantes/química , Fator 2 Relacionado a NF-E2/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Heme Oxigenase-1/metabolismo , Humanos
3.
Int J Qual Health Care ; 35(2)2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37148306

RESUMO

The COVID -19 pandemic impacted acute myocardial infarction (AMI) attendances, ST-elevation myocardial infarction (STEMI) treatments, and outcomes. We collated data from majority of primary percutaneous coronary intervention (PPCI)-capable public healthcare centres in Singapore to understand the initial impact COVID-19 had on essential time-critical emergency services. We present data comparisons from 'Before Disease Outbreak Response System Condition (DORSCON) Orange', 'DORSCON Orange to start of circuit breaker (CB)', and during the first month of 'CB'. We collected aggregate numbers of weekly elective PCI from four centres and AMI admissions, PPCI, and in-hospital mortality from five centres. Exact door-to-balloon (DTB) times were recorded for one centre; another two reported proportions of DTB times exceeding targets. Median weekly elective PCI cases significantly decreased from 'Before DORSCON Orange' to 'DORSCON Orange to start of CB' (34 vs 22.5, P = 0.013). Median weekly STEMI admissions and PPCI did not change significantly. In contrast, the median weekly non-STEMI (NSTEMI) admissions decreased significantly from 'Before DORSCON Orange' to 'DORSCON Orange to start of CB' (59 vs 48, P = 0.005) and were sustained during CB (39 cases). Exact DTB times reported by one centre showed no significant change in the median. Out of three centres, two reported significant increases in the proportion that exceeded DTB targets. In-hospital mortality rates remained static. In Singapore, STEMI and PPCI rates remained stable, while NSTEMI rates decreased during DORSCON Orange and CB. The severe acute respiratory syndrome (SARS) experience may have helped prepare us to maintain essential services such as PPCI during periods of acute healthcare resource strain. However, data must be monitored and increased pandemic preparedness measures must be explored to ensure that AMI care is not adversely affected by continued COVID fluctuations and future pandemics.


Assuntos
COVID-19 , Infarto do Miocárdio , Infarto do Miocárdio sem Supradesnível do Segmento ST , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , COVID-19/epidemiologia , COVID-19/terapia , Pandemias , Singapura/epidemiologia , Infarto do Miocárdio/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Resultado do Tratamento , Estudos Retrospectivos
4.
Cardiovasc Diabetol ; 20(1): 211, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34666746

RESUMO

BACKGROUND: Stress-induced hyperglycaemia at time of hospital admission has been linked to worse prognosis following acute myocardial infarction (AMI). In addition to glucose, other glucose-related indices, such as HbA1c, glucose-HbA1c ratio (GHR), and stress-hyperglycaemia ratio (SHR) are potential predictors of clinical outcomes following AMI. However, the optimal blood glucose, HbA1c, GHR, and SHR cut-off values for predicting adverse outcomes post-AMI are unknown. As such, we determined the optimal blood glucose, HbA1c, GHR, and SHR cut-off values for predicting 1-year all cause mortality in diabetic and non-diabetic ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI) patients. METHODS: We undertook a national, registry-based study of patients with AMI from January 2008 to December 2015. We determined the optimal blood glucose, HbA1c, GHR, and SHR cut-off values using the Youden's formula for 1-year all-cause mortality. We subsequently analyzed the sensitivity, specificity, positive and negative predictive values of the cut-off values in the diabetic and non-diabetic subgroups, stratified by the type of AMI. RESULTS: There were 5841 STEMI and 4105 NSTEMI in the study. In STEMI patients, glucose, GHR, and SHR were independent predictors of 1-year all-cause mortality [glucose: OR 2.19 (95% CI 1.74-2.76); GHR: OR 2.28 (95% CI 1.80-2.89); SHR: OR 2.20 (95% CI 1.73-2.79)]. However, in NSTEMI patients, glucose and HbA1c were independently associated with 1-year all-cause mortality [glucose: OR 1.38 (95% CI 1.01-1.90); HbA1c: OR 2.11 (95% CI 1.15-3.88)]. In diabetic STEMI patients, SHR performed the best in terms of area-under-the-curve (AUC) analysis (glucose: AUC 63.3%, 95% CI 59.5-67.2; GHR 68.8% 95% CI 64.8-72.8; SHR: AUC 69.3%, 95% CI 65.4-73.2). However, in non-diabetic STEMI patients, glucose, GHR, and SHR performed equally well (glucose: AUC 72.0%, 95% CI 67.7-76.3; GHR 71.9% 95% CI 67.7-76.2; SHR: AUC 71.7%, 95% CI 67.4-76.0). In NSTEMI patients, glucose performed better than HbA1c for both diabetic and non-diabetic patients in AUC analysis (For diabetic, glucose: AUC 52.8%, 95% CI 48.1-57.6; HbA1c: AUC 42.5%, 95% CI 37.6-47. For non-diabetic, glucose: AUC 62.0%, 95% CI 54.1-70.0; HbA1c: AUC 51.1%, 95% CI 43.3-58.9). The optimal cut-off values for glucose, GHR, and SHR in STEMI patients were 15.0 mmol/L, 2.11, and 1.68 for diabetic and 10.6 mmol/L, 1.72, and 1.51 for non-diabetic patients respectively. For NSTEMI patients, the optimal glucose values were 10.7 mmol/L for diabetic and 8.1 mmol/L for non-diabetic patients. CONCLUSIONS: SHR was the most consistent independent predictor of 1-year all-cause mortality in both diabetic and non-diabetic STEMI, whereas glucose was the best predictor in NSTEMI patients.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus/sangue , Hemoglobinas Glicadas/metabolismo , Infarto do Miocárdio sem Supradesnível do Segmento ST/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Idoso , Biomarcadores/sangue , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/mortalidade , Diabetes Mellitus/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio sem Supradesnível do Segmento ST/mortalidade , Infarto do Miocárdio sem Supradesnível do Segmento ST/terapia , Admissão do Paciente , Valor Preditivo dos Testes , Prognóstico , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/mortalidade , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Singapura/epidemiologia , Fatores de Tempo
5.
Inorg Chem ; 59(23): 16824-16828, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33200921

RESUMO

The synthesis, properties, X-ray structures, and catalytic sulfur-atom-transfer (SAT) reactions of W2(µ-S)(µ-S2)(dtc)2(dped)2 [1; dtc = S2CNR2-, where R = Me, Et, iBu, and Bn; dped = S2C2Ph22-] and W2(µ-S)2(dtc)2(dped)2 (2) are reported. These complexes represent the oxidized (1) and reduced (2) forms of anaerobic SAT catalysts operating through the bidirectional, ligand-based half-reaction (µ-S)(µ-S2) ↔ (µ-S)2 + S0. The catalysts are deactivated in air through the formation of catalytically inactive oxo complexes, (dtc)WO(µ-S)(µ-dped)W(dtc)(dped) (3), prompting us to recommend that group 6 SAT activity be assessed under strictly anaerobic conditions.

6.
J Card Fail ; 25(7): 571-575, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30822512

RESUMO

BACKGROUND: Risk scores predicting in-patient mortality in heart failure patients have not been designed specifically for Asian patients. We aimed to validate and recalibrate the OPTIMIZE-HF risk model for in-hospital mortality in a multiethnic Asian population hospitalized for heart failure. METHODS AND RESULTS: Data from the Singapore Cardiac Databank Heart Failure on patients admitted for heart failure from January 1, 2008, to December 31, 2013, were included. The primary outcome studied was in-hospital mortality. Two models were compared: the original OPTIMIZE-HF risk model and a modified OPTIMIZE-HF risk model (similar variables but with coefficients derived from our cohort). A total of 15,219 patients were included. The overall in-hospital mortality was 1.88% (n = 286). The original model had a C-statistic of 0.739 (95% CI 0.708-0.770) with a good match between predicted and observed mortality rates (Hosmer-Lemeshow statistic 13.8; P = .086). The modified model had a C-statistic of 0.741 (95% CI 0.709-0.773) but a significant difference between predicted and observed mortality rates (Hosmer-Lemeshow statistic 17.2; P = .029). The modified model tended to underestimate risk at the extremes (lowest and highest ends) of risk. CONCLUSIONS: We provide the first independent validation of the OPTIMIZE-HF risk score in an Asian population. This risk model has been shown to perform reliably in our Asian cohort and will potentially provide clinicians with a useful tool to identify high-risk heart failure patients for more intensive management.


Assuntos
Regras de Decisão Clínica , Insuficiência Cardíaca , Mortalidade Hospitalar , Volume Sistólico , Idoso , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde/métodos , Prognóstico , Sistema de Registros/estatística & dados numéricos , Reprodutibilidade dos Testes , Singapura/epidemiologia , Análise de Sobrevida
7.
Environ Monit Assess ; 187(3): 138, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25712628

RESUMO

Source attribution of mercury (Hg) is critical for policy development to minimize the impact of Hg in wastes. Mercury content of consumer products and its subsequent release into the waste stream of Cebu City, Philippines, is estimated through surveys that employed validated, enumerator-administered questionnaires. Initially, a citywide survey (n = 1636) indicates that each household annually generates 1.07 ppm Hg (i.e., mg Hg/kg waste) and that linear and compact fluorescent lamps (17.2 %) and thermometers (52.1 %) are the major sources of Hg. A subsequent survey (n = 372) in the vicinity of the city's municipal solid waste landfill shows that residents in the area annually generate 0.38 ppm Hg per household, which is less than the citywide mean; surprisingly though, less affluent respondents living closer to the landfill site reported more Hg from thermometers and sphygmomanometers. Analysis of collected soil (0.238 ppm), leachate water (6.5 ppb), sediment (0.109 ppm), and three plants (0.393 to 0.695 ppm) shows no significant variation throughout five stations in and around the landfill site, although the period of collection is significant for soil (P = 0.001) and Cenchrus echinatus (P = 0.016). Detected Hg in the landfill is considerably less than the annual estimated release, indicating that there is minimal accumulation of Hg in the soil or in plants. As a result of this project, a policy brief has been provided to the Cebu City council in aid of hazardous waste legislation.


Assuntos
Monitoramento Ambiental , Poluentes Ambientais/análise , Resíduos Perigosos/análise , Mercúrio/análise , Cidades , Água Doce/química , Sedimentos Geológicos/química , Humanos , Filipinas , Plantas/química , Solo/química , Instalações de Eliminação de Resíduos , Água/análise
8.
Dis Colon Rectum ; 57(1): 115-26, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24316955

RESUMO

BACKGROUND: Sham feeding has been shown to hasten the return of GI function following colorectal surgery, before the advent of enhanced recovery after surgery protocols. Few data exist regarding the efficacy of sham feeding in the modern era, with rapid postoperative feeding. OBJECTIVE: We sought to perform a meta-analysis on the effect of sham feeding in colorectal surgery, with a separate analysis on trials that used rapid postoperative feeding. DATA SOURCES: Cochrane, MEDLINE, EMBASE, Scopus, and PubMed were searched by using the terms gum OR sham feeding OR chew AND (colorect OR resect). STUDY SELECTION: All studies were randomized controlled trials (in any language) performed on adults, comparing standard care with gum chewing following colorectal resection. From 439 citations, 10 articles were included. INTERVENTION: The intervention was sham feeding by means of gum chewing. MAIN OUTCOME MEASURES: The outcome measures were time to return of flatus, time to first bowel movement, complication rates, length of hospital stay, readmission rates, and reoperation rates. RESULTS: Ten randomized controlled trials (n = 612) were included. Sham feeding resulted in a reduction in time to flatus of 31 minutes (p = 0.003) and time to first bowel movement of 30 minutes (p = 0.05). Sham feeding also resulted in a reduction in length of stay by 0.5 days (p = 0.007), and a reduction in complication rates (relative risk = 0.687, p = 0.017), although this appeared to be associated with publication bias. Analysis of trials that used rapid postoperative feeding (n = 282) revealed no difference in postoperative GI function. LIMITATIONS: This review was limited by the heterogeneity of postoperative feeding regimes, in addition to limited reporting by trials of postoperative morbidity. CONCLUSIONS: Sham feeding following colorectal surgery is safe, results in small improvements in GI recovery, and is associated with a reduction in the length of hospital stay. It confers no advantage if patients are placed on a rapid postoperative feeding regime.


Assuntos
Goma de Mascar , Colectomia , Mastigação , Cuidados Pós-Operatórios/métodos , Recuperação de Função Fisiológica , Humanos , Modelos Estatísticos , Avaliação de Resultados em Cuidados de Saúde , Placebos , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
ChemMedChem ; : e202400038, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38818625

RESUMO

Hearing loss is a significant disability that often goes under recognised, largely due to poor identification, prevention, and treatment. Steps are being made to amend these pitfalls in the investigation of hearing loss, however, the development of a cure to reverse advanced forms remains distant. This review details some current advances in the treatment of hearing loss, with a particular focus on genetic-based nanotechnology and how it may provide a useful avenue for further research. This review presents a broad background on the pathophysiology of hearing loss and some current interventions. We also highlight some potential genes that may be useful in the amelioration of hearing loss. Pathways of cellular differentiation from stem or supporting cell to functional hair cell are covered in detail, as this mechanism represents a key means of regenerating these cell types. Overall, we believe that polymer-based nanotechnology coupled with novel excipients represents a useful area of further research in the treatment of hearing loss, although further studies in this area are required.

10.
Ann Surg ; 257(6): 1016-24, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23470575

RESUMO

OBJECTIVE: To determine whether sham feeding with chewing gum improved gastrointestinal recovery after colorectal resection surgery, in the presence of routine postoperative feeding. BACKGROUND: Sham feeding with chewing gum has been shown to accelerate the return of gut function after colorectal surgery. This study sought to determine whether sham feeding with gum, after colorectal resection, accelerates return of gastrointestinal function in patients on a rapid feeding enhanced recovery program. METHODS: A randomized "two armed" controlled clinical trial was performed. Equal groups of open and laparoscopic colorectal resection surgical patients were recruited. Patients in the intervention arm received chewing gum 4 times a day postoperatively. All patients in the trial were placed on an established, standardized Enhanced Recovery After Surgery program. The primary outcome was time to return of gut function, assessed by time to flatus and first bowel motion. Secondary outcomes were time to tolerate diet, symptoms of ileus in the form of nausea, vomiting and distension, pain as assessed by analgesic consumption and visual analogue scales, complications, and length of hospital stay. RESULTS: A total of 161 patients were recruited. Postoperative morbidity was equivalent between groups, with no complications related to gum chewing. There was no difference between groups with respect to the primary outcomes of time to flatus and bowel motion. There was less perception of pain in the intervention group on days 2 to 5, and no difference with respect to all other secondary outcomes. CONCLUSIONS: Sham feeding with gum, after open and laparoscopic colorectal resectional surgery is safe, but does not hasten the return of gastrointestinal function in patients who receive accelerated postoperative feeding. (ACTRN12607000538448).


Assuntos
Goma de Mascar , Cirurgia Colorretal , Procedimentos Cirúrgicos Eletivos , Motilidade Gastrointestinal , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Laparoscopia , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , New South Wales , Medição da Dor , Complicações Pós-Operatórias , Náusea e Vômito Pós-Operatórios , Recuperação de Função Fisiológica
11.
Acta Crystallogr C ; 69(Pt 9): 977-80, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24005503

RESUMO

The title complex, [Cu(C5H10NS2)(C15H22BN6)] or (Tp(Me2))Cu(S2CNEt2), incorporating the classic Tp(Me2) scorpionate, is relevant to blue copper protein models and to Cu extraction from waste treatment and mine-tailing leachate. The IR and UV-Vis spectra are consistent with the crystal structure.

12.
Nat Commun ; 14(1): 4885, 2023 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-37573411

RESUMO

Fluorescent proteins (FP) are frequently used for studying proteins inside cells. In advanced fluorescence microscopy, FPs can report on additional intracellular variables. One variable is the local density near FPs, which can be useful in studying densities within cellular bio-condensates. Here, we show that a reduction in fluorescence lifetimes of common monomeric FPs reports increased levels of local densities. We demonstrate the use of this fluorescence-based variable to report the distribution of local densities within heterochromatin protein 1α (HP1α) in mouse embryonic stem cells (ESCs), before and after early differentiation. We find that local densities within HP1α condensates in pluripotent ESCs are heterogeneous and cannot be explained by a single liquid phase. Early differentiation, however, induces a change towards a more homogeneous distribution of local densities, which can be explained as a liquid-like phase. In conclusion, we provide a fluorescence-based method to report increased local densities and apply it to distinguish between homogeneous and heterogeneous local densities within bio-condensates.


Assuntos
Núcleo Celular , Células-Tronco Embrionárias , Animais , Camundongos , Núcleo Celular/metabolismo , Diferenciação Celular , Células-Tronco Embrionárias/metabolismo , Heterocromatina/metabolismo , Homólogo 5 da Proteína Cromobox
13.
Nanomedicine (Lond) ; 18(19): 1247-1260, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37665059

RESUMO

Background: Hearing loss is a condition that may affect a wide array of patients from various backgrounds. There are no cures for sensorineural hearing loss. Gene therapy is one possible method of improving hearing status; however, gene delivery remains challenging. Materials & methods: Polymer nanoaggregates of alginate and poly-L-lysine were prepared with and without bile acid. The nanoaggregates had physical properties, cytotoxicity, gene release and gene expression analyzed. Results & discussion: The nanoparticles produced had appropriate size and charge, low cytotoxicity between 0.5 and 1.0 mg/ml and linear gene release but poor transfection efficiency. Conclusion: The present study provides preliminary evidence for the efficacy of polymer nanotechnology with bile acids for inner ear gene delivery; optimization is required to improve transfection efficiency.


Hearing loss is a global issue with significant consequences. Gene therapy is an emerging technique in the management of various conditions, including hearing loss. This involves the delivery of a new copy of a gene to a cell with a missing or defective copy of that gene. The delivery of genes such as ATOH1 has been shown to encourage cell differentiation into new functional hair cells to potentially reverse hearing loss. Unfortunately, effective and safe delivery of genes remains challenging. Polymer nanoparticles represent one method for delivering genes that allows for customizability in size, structure and function. In this study, the authors developed nanoparticles with a polymer derived from algae called alginate, an amino acid polymer called poly-L-lysine and bile acid to improve gene delivery to inner ear cells. A cell line derived from the inner ear of a mouse was used to test the effectiveness of these particles at delivering genes. A gene that makes cells that uptake these particles fluoresce was included in the nanoparticles, to demonstrate they are capable of gene delivery. In the future, this gene could be replaced with genes associated with encouraging cell differentiation. The preliminary results of this study suggest that such nanoparticles may be capable of gene delivery, although further optimization is required.

14.
Nanomedicine (Lond) ; 18(12): 923-940, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37529927

RESUMO

Background: Sensorineural hearing loss has been associated with oxidative stress. However, an antioxidant that passes effectively through the ear remains elusive. Method: Probucol (PB)-based nanoparticles were formed using a spray-drying encapsulation technique, characterized and tested in vitro. Results: Uniform, spherical nanoparticles were produced. The addition of lithocholic acid to PB formulations did not affect drug content or production yield, but it did modify capsule size, surface tension, electrokinetic stability and drug release. Cell viability, bioenergetics and inflammatory profiles were improved when auditory cells were exposed to PB-based nanoparticles, which showed antioxidant properties (p < 0.05). Conclusion: PB-based nanoparticles can potentially protect the auditory cell line from oxidative stress and could be used in future in vivo studies as a potential new therapeutic agent for sensorineural hearing loss.


Oxidative stress is an imbalance of cellular processes in which the production of free radicals outweighs the cellular defense mechanism. The association of oxidative stress with the pathophysiology of sensorineural hearing loss (SHL) is well established. SHL development is associated with chronic damage in the structure of the inner ear or auditory nerve. Therefore, potent antioxidants such as probucol could be one way to prevent or treat SHL. However, due to its isolated position, SHL is challenging to treat, imposing a desperate need for refining existing therapeutic methods; one way to do this is by optimizing the formulation using nanoparticles. We aimed to design a novel, stable formulation of PB using polymers and excipients to develop nanoparticles and examine the efficiency of these formulations on the HEI-OC1 stress cell line. We found that the prepared nanoparticle is robust and stable and protects HEI-OC1 from cellular toxicity and oxidative stress. It could be a novel therapeutic agent to treat or prevent SHL.


Assuntos
Perda Auditiva Neurossensorial , Nanopartículas , Humanos , Probucol/farmacologia , Antioxidantes/farmacologia , Ácidos e Sais Biliares/farmacologia , Estresse Oxidativo , Perda Auditiva Neurossensorial/tratamento farmacológico , Perda Auditiva Neurossensorial/prevenção & controle , Audição , Preparações Farmacêuticas
15.
Singapore Med J ; 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37338492

RESUMO

Introduction: Data on heart failure (HF) with mildly reduced ejection fraction (HFmrEF) is still emerging, especially in Asian populations. This study aims to compare the clinical characteristics and outcomes of Asian HFmrEF patients with those of HF patients with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF). Methods: Patients admitted nationally for HF between 2008 and 2014 were included in the study. They were categorised according to ejection fraction (EF). Patients with EF <40%, EF 40%-49% and EF ≥50% were categorised into the following groups: HFrEF, HFmrEF and HFpEF, respectively. All patients were followed up till December 2016. Primary outcome was all-cause mortality. Secondary outcomes included cardiovascular death and/or HF rehospitalisations. Results: A total of 16,493 patients were included in the study - HFrEF, n = 7,341 (44.5%); HFmrEF, n = 2,272 (13.8%); and HFpEF n = 6,880 (41.7%). HFmrEF patients were more likely to be gender neutral, of mid-range age and have concomitant diabetes mellitus, hyperlipidaemia, peripheral vascular disease and coronary artery disease (P < 0.001). The two-year overall mortality rates for HFrEF, HFmrEF and HFpEF were 32.9%, 31.8% and 29.1%, respectively. HFmrEF patients had a significantly lower overall mortality rate compared to HFrEF patients (adjusted hazard ratio [HR] 0.89, 95% confidence interval [CI] 0.83-0.95; P < 0.001) and a significantly higher overall mortality rate (adjusted HR 1.25, 95% CI 1.17-1.33; P < 0.001) compared to HFpEF patients. This was similarly seen with cardiovascular mortality and HF hospitalisations, with the exception of similar HF hospitalisations between HFmrEF and HFpEF patients. Conclusion: HFmrEF patients account for a significant burden of patients with HF. HFmrEF represents a distinct HF phenotype with high atherosclerotic burden and clinical outcomes saddled in between those of HFrEF and HFpEF. Further therapeutic studies to guide management of this challenging group of patients are warranted.

16.
Front Immunol ; 14: 1155770, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37313412

RESUMO

Introduction: Many people with long COVID symptoms suffer from debilitating neurologic post-acute sequelae of SARS-CoV-2 infection (Neuro-PASC). Although symptoms of Neuro-PASC are widely documented, it is still unclear whether PASC symptoms impact virus-specific immune responses. Therefore, we examined T cell and antibody responses to SARS-CoV-2 Nucleocapsid protein to identify activation signatures distinguishing Neuro-PASC patients from healthy COVID convalescents. Results: We report that Neuro-PASC patients exhibit distinct immunological signatures composed of elevated CD4+ T cell responses and diminished CD8+ memory T cell activation toward the C-terminal region of SARS-CoV-2 Nucleocapsid protein when examined both functionally and using TCR sequencing. CD8+ T cell production of IL-6 correlated with increased plasma IL-6 levels as well as heightened severity of neurologic symptoms, including pain. Elevated plasma immunoregulatory and reduced pro-inflammatory and antiviral response signatures were evident in Neuro-PASC patients compared with COVID convalescent controls without lasting symptoms, correlating with worse neurocognitive dysfunction. Discussion: We conclude that these data provide new insight into the impact of virus-specific cellular immunity on the pathogenesis of long COVID and pave the way for the rational design of predictive biomarkers and therapeutic interventions.


Assuntos
Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , COVID-19 , Síndrome de COVID-19 Pós-Aguda , Humanos , COVID-19/imunologia , Interleucina-6 , Síndrome de COVID-19 Pós-Aguda/imunologia , SARS-CoV-2
18.
Front Cardiovasc Med ; 10: 1142078, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37435049

RESUMO

Introduction: Obesity is an important risk factor for acute myocardial infarction (AMI), but the interplay between metabolic health and obesity on AMI mortality has been controversial. In this study, we aimed to elucidate the risk of short- and long-term all-cause mortality by obesity and metabolic health in AMI patients using data from a multi-ethnic national AMI registry. Methods: A total of 73,382 AMI patients from the national Singapore Myocardial Infarction Registry (SMIR) were included. These patients were classified into four groups based on the presence or absence of metabolic diseases, diabetes mellitus, hyperlipidaemia, and hypertension, and obesity: (1) metabolically-healthy-normal-weight (MHN); (2) metabolically-healthy-obese (MHO); (3) metabolically-unhealthy-normal-weight (MUN); and (4) metabolically-unhealthy-obese (MUO). Results: MHO patients had reduced unadjusted risk of all-cause in-hospital, 30-day, 1-year, 2-year, and 5-year mortality following the initial MI event. However, after adjusting for potential confounders, the protective effect from MHO on post-AMI mortality was lost. Furthermore, there was no reduced risk of recurrent MI or stroke within 1-year from onset of AMI by the MHO status. However, the risk of 1-year mortality was higher in female and Malay AMI patients with MHO compared to MHN even after adjusting for confounders. Conclusion: In AMI patients with or without metabolic diseases, the presence of obesity did not affect mortality. The exception to this finding were female and Malay MHO who had worse long-term AMI mortality outcomes when compared to MHN suggesting that the presence of obesity in female and Malay patients may confer worsened outcomes.

19.
Am J Med ; 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37220832

RESUMO

BACKGROUND: Persistent multi-organ symptoms after coronavirus disease 2019 (COVID-19) have been termed "long COVID" or "post-acute sequelae of SARS-CoV-2 infection." The complexity of these clinical manifestations posed challenges early in the pandemic as different ambulatory models formed out of necessity to manage the influx of patients. Little is known about the characteristics and outcomes of patients seeking care at multidisciplinary post-COVID centers. METHODS: We performed a retrospective cohort study of patients evaluated at our multidisciplinary comprehensive COVID-19 center in Chicago, Ill, between May 2020 and February 2022. We analyzed specialty clinic utilization and clinical test results according to severity of acute COVID-19. RESULTS: We evaluated 1802 patients a median of 8 months from acute COVID-19 onset, including 350 post-hospitalization and 1452 non-hospitalized patients. Patients were seen in 2361 initial visits in 12 specialty clinics, with 1151 (48.8%) in neurology, 591 (25%) in pulmonology, and 284 (12%) in cardiology. Among the patients tested, 742/878 (85%) reported decreased quality of life, 284/553 (51%) had cognitive impairment, 195/434 (44.9%) had alteration of lung function, 249/299 (83.3%) had abnormal computed tomography chest scans, and 14/116 (12.1%) had elevated heart rate on rhythm monitoring. Frequency of cognitive impairment and pulmonary dysfunction was associated with severity of acute COVID-19. Non-hospitalized patients with positive SARS-CoV-2 testing had findings similar to those with negative or no test results. CONCLUSIONS: The experience at our multidisciplinary comprehensive COVID-19 center shows common utilization of multiple specialists by long COVID patients, who harbor frequent neurologic, pulmonary, and cardiologic abnormalities. Differences in post-hospitalization and non-hospitalized groups suggest distinct pathogenic mechanisms of long COVID in these populations.

20.
Lancet Reg Health West Pac ; 37: 100803, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37693863

RESUMO

Background: Understanding the trajectories of metabolic risk factors for acute myocardial infarction (AMI) is necessary for healthcare policymaking. We estimated future projections of the incidence of metabolic diseases in a multi-ethnic population with AMI. Methods: The incidence and mortality contributed by metabolic risk factors in the population with AMI (diabetes mellitus [T2DM], hypertension, hyperlipidemia, overweight/obesity, active/previous smokers) were projected up to year 2050, using linear and Poisson regression models based on the Singapore Myocardial Infarction Registry from 2007 to 2018. Forecast analysis was stratified based on age, sex and ethnicity. Findings: From 2025 to 2050, the incidence of AMI is predicted to rise by 194.4% from 482 to 1418 per 100,000 population. The largest percentage increase in metabolic risk factors within the population with AMI is projected to be overweight/obesity (880.0% increase), followed by hypertension (248.7% increase), T2DM (215.7% increase), hyperlipidemia (205.0% increase), and active/previous smoking (164.8% increase). The number of AMI-related deaths is expected to increase by 294.7% in individuals with overweight/obesity, while mortality is predicted to decrease by 11.7% in hyperlipidemia, 29.9% in hypertension, 32.7% in T2DM and 49.6% in active/previous smokers, from 2025 to 2050. Compared with Chinese individuals, Indian and Malay individuals bear a disproportionate burden of overweight/obesity incidence and AMI-related mortality. Interpretation: The incidence of AMI is projected to continue rising in the coming decades. Overweight/obesity will emerge as fastest-growing metabolic risk factor and the leading risk factor for AMI-related mortality. Funding: This research was supported by the NUHS Seed Fund (NUHSRO/2022/058/RO5+6/Seed-Mar/03) and National Medical Research Council Research Training Fellowship (MOH-001131). The SMIR is a national, ministry-funded registry run by the National Registry of Diseases Office and funded by the Ministry of Health, Singapore.

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