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1.
Transfusion ; 64(8): 1492-1502, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38940011

RESUMEN

BACKGROUND: Studies preceding the COVID-19 pandemic found that slower time-to-return was associated with first-time, deferred, and mobile drive blood donors. How donor return dynamics changed during the COVID-19 pandemic is not well understood. METHODS: We analyzed visits by whole blood donors from 2017 to 2022 in South Africa (SA) and the United States (US) stratified by mobile and fixed environment, first-time and repeat donor status, and pre-COVID19 (before March 2020) and intra-COVID19. We used Kaplan-Meier curves to characterize time-to-return, cumulative incidence functions to analyze switching between donation environments, and Cox proportional hazards models to analyze factors influencing time-to-return. RESULTS: Overall time-to-return was shorter in SA. Pre-COVID19, the proportion of donors returning within a year of becoming eligible was lower for deferred donors in both countries regardless of donation environment and deferral type. Intra-COVID19, the gap between deferred and non-deferred donors widened in the US but narrowed in SA, where efforts to schedule return visits from deferred donors were intensified, particularly for non-hemoglobin-related deferrals. Intra-COVID19, the proportion of donors returning within a year in SA was higher for deferred first-time donors (>81%) than for successful first-time donors (80% at fixed sites; 69% at mobile drives). CONCLUSIONS: The pandemic complicated efforts to recruit new donors and schedule returning visits after completed donations. Concerted efforts to improve time-to-return for deferred donors helped mitigate donation loss in SA during the public health emergency.


Asunto(s)
Donantes de Sangre , COVID-19 , SARS-CoV-2 , Humanos , Donantes de Sangre/estadística & datos numéricos , COVID-19/epidemiología , Sudáfrica/epidemiología , Estados Unidos/epidemiología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Pandemias
2.
BMC Pulm Med ; 23(1): 211, 2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37328740

RESUMEN

BACKGROUND: The differential expression of circular RNAs (circRNAs) in individuals with very severe chronic obstructive pulmonary disease (COPD) and healthy individuals was screened using microarray technology. The related functions and mechanisms were analyzed using bioinformatic methods to explore the potential of target circRNAs as biomarkers of COPD and provide insights for future pathogenesis. PATIENTS AND METHODS: Thirty patients with very severe COPD and thirty healthy controls were diagnosed at The Second People's Hospital of Hefei from September 2021 to September 2022. The differential expression of circRNAs was compared and analyzed using a gene microarray and verified using quantitative real-time polymerase chain reaction (qRT-PCR) technology. RESULTS: A total of 90 upregulated and 29 downregulated circRNAs were screened in patients with very severe COPD and compared with those in healthy controls. qRT-PCR analysis showed that hsa_circ_0062683 of patients with very severe COPD was significantly upregulated, and hsa_circ_0089763 and hsa_circ_0008882 were significantly downregulated. By constructing the circRNA-miRNA interaction network, it was found that hsa-miR-612, hsa-miR-593-5p, hsa-miR-765, and hsa-miR-103a-2-5p are the miRNAs regulated by more differentially expressed circRNAs (DEcircRNAs). DEcircRNAs may participate in the development of COPD through hypoxia or regulation of various immune cells. CONCLUSION: Plasma circRNAs may play a helpful role in the diagnosis and assessment of COPD and be valuable disease biomarkers.


Asunto(s)
MicroARNs , Enfermedad Pulmonar Obstructiva Crónica , Humanos , ARN Circular/genética , MicroARNs/metabolismo , Biomarcadores , Análisis por Micromatrices , Enfermedad Pulmonar Obstructiva Crónica/genética , Biología Computacional
3.
Can J Anaesth ; 67(2): 213-224, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31529369

RESUMEN

PURPOSE: There is conflicting evidence regarding the influence of intensive care unit (ICU) occupancy at the time of admission on important patient outcomes such as mortality. The objective of this analysis was to characterize the association between ICU occupancy at the time of ICU admission and subsequent mortality. METHODS: This single-centre, retrospective cohort study included all patients admitted to the ICU at the Vancouver General Hospital between 4 January 2010 and 8 October 2017. Intensive care unit occupancy was defined as the number of ICU bed hours utilized in a day divided by the total amount of ICU bed hours available for that day. We constructed mixed-effects logistic regression models controlling for relevant covariates to assess the impact of admission occupancy quintiles on total inpatient (ICU and ward) and early (72-hr) ICU mortality. RESULTS: This analysis included 10,365 ICU admissions by 8,562 unique patients. Compared with ICU admissions in the median occupancy quintile, admissions in the highest and second highest occupancy quintile were associated with a significant increase in the odds of inpatient mortality (highest: odds ratio [OR], 1.33; 95% confidence interval [CI], 1.12 to 1.59; P value < 0.001; second highest: OR, 1.21; 95% CI, 1.02 to 1.44; P value < 0.03). No association between admission occupancy and 72-hr ICU mortality was observed. CONCLUSIONS: Admission to the ICU on days of high occupancy was associated with increased inpatient mortality, but not with increased 72-hr ICU mortality. Capacity strain on the ICU may result in significant negative consequences for patients, but further research is needed to fully characterize the complex effects of capacity strain.


Asunto(s)
Mortalidad Hospitalaria , Pacientes Internos , Unidades de Cuidados Intensivos , Hospitalización , Humanos , Admisión del Paciente , Estudios Retrospectivos
4.
Nano Lett ; 18(8): 4900-4907, 2018 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-29985626

RESUMEN

Ultrathin nanowires with <3 nm diameter have long been sought for novel properties that emerge from dimensional constraint as well as for continued size reduction and performance improvement of nanoelectronic devices. Here, we report on a facile and large-scale synthesis of a new class of electrically conductive ultrathin core-shell nanowires using benzenethiols. Core-shell nanowires are atomically precise and have inorganic five-atom copper-sulfur cross-sectional cores encapsulated by organic shells encompassing aromatic substituents with ring planes oriented parallel. The exact nanowire atomic structures were revealed via a two-pronged approach combining computational methods coupled with experimental synthesis and advanced characterizations. Core-shell nanowires were determined to be indirect bandgap materials with a predicted room-temperature resistivity of ∼120 Ω·m. Nanowire morphology was found to be tunable by changing the interwire interactions imparted by the functional group on the benzenethiol molecular precursors, and the nanowire core diameter was determined by the steric bulkiness of the ligand. These discoveries help define our understanding of the fundamental constituents of atomically well-defined and electrically conductive core-shell nanowires, representing significant advances toward nanowire building blocks for smaller, faster, and more powerful nanoelectronics.

5.
Artículo en Inglés | MEDLINE | ID: mdl-36993790

RESUMEN

Purpose: To investigate the potential of plasma microRNA-150-5p (miR-150-5p) as a biomarker for chronic obstructive pulmonary disease (COPD) and its relationship with clinical indicators such as pulmonary function. Patients and Methods: Fifty-nine patients with COPD and twenty-six healthy control individuals were recruited in the Second People's Hospital of Hefei from September 2021 to September 2022. The plasma expression level of miR-150-5p was measured by quantitative real-time polymerase chain reaction. Results: The miR-150-5p level in the COPD group was significantly lower than that in the control group, and the relative expression was lower in patients with severe airflow limitation than those with mild limitation. Plasma miR-150-5p levels were positively correlated with pulmonary function indicators and negatively correlated with the white blood cell count and C-reactive protein level. The receiver operating characteristic curve suggested that plasma miR-150-5p had predictive value for COPD (area under curve = 0.819, sensitivity 64.4%, specificity 92.3%). Conclusion: MiR-150-5p can be useful for the diagnosis and disease assessment of COPD, and has value as a biomarker for COPD.


Asunto(s)
MicroARNs , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/genética , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , MicroARNs/metabolismo , Biomarcadores/metabolismo , Pulmón/metabolismo , Curva ROC
6.
ACS Appl Mater Interfaces ; 12(23): 26405-26412, 2020 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-32403921

RESUMEN

Emerging moisture sensitive devices require robust encapsulation strategies to inhibit water ingress and prevent premature failure. A scalable, open-air plasma process has been developed to deposit alternating layers of conformal organosilicate and dense SiO2 thin-film barriers to prevent moisture ingress. The in situ low-temperature process is suitable for direct deposition on thermally sensitive devices and is compatible with flexible polymeric substrates. Using optical calcium testing, low water vapor transmission rates on the order of 10-3 g/m2/day at an accelerated aging condition of 38 °C and 90% relative humidity (RH) are achieved. Using moisture-sensitive perovskite devices as a representative moisture-susceptible device, devices retain over 80% of their initial performance for over 660 h in a 50 °C 50% RH accelerated aging environment. The ability of the multilayer barrier to enable device resistance to humid environments is crucial toward realizing longer operating lifetimes.

7.
Plast Reconstr Surg Glob Open ; 8(4): e2769, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32440436

RESUMEN

BACKGROUND: Because plastic surgeons do not "own" a specific anatomic region, other surgical specialties have increasingly assumed procedures historically performed by plastic surgery. Decreased case volume is postulated to be associated with higher complication rates. Herein, we investigate whether volume and surgical specialty have an impact on microsurgical complications, specifically surgical site infection (SSI) and reoperation rates. METHODS: The 2005-2015 National Surgical Quality Improvement Program participant use file was queried by Current Procedural Terminology code for breast and head/neck microsurgeries. Multivariate logistic regression was performed to compare the outcomes between surgical specialties. A cumulative frequency variable was introduced to investigate the effect of case volume on complication rates. RESULTS: We captured 6,617 microsurgical cases. Multivariate logistic regression revealed that although the rate of SSI was lower in plastic surgery compared with otolaryngology for head and neck reconstructions (13.3% versus 10.5%) and compared with general surgery for breast reconstructions (5.4% versus 4.7%), there was no significant difference between specialties (P = 0.13; P = 0.96). Increased case volume is negatively correlated with complications. CONCLUSIONS: Plastic surgery is at risk given case cannibalization by other specialties. We conclude that surgical specialty does not affect the rates of SSI and reoperation. We demonstrate a correlation between lower volumes and increased complications, implying that, once a specialty has amassed critical case experience, complication rates may decrease, and outcomes can be equivalent or superior. Case breadth and volumes should be maintained to preserve skills, optimize outcomes, and maintain the specialty as it currently exists.

8.
Plast Surg (Oakv) ; 28(1): 57-66, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32110646

RESUMEN

BACKGROUND: There is a lack of large-scale data that examine complications in plastic surgery. A description of baseline rates and patient outcomes allows better understanding of ways to improve patient care and cost-savings for health systems. Herein, we determine the most frequent complications in plastic surgery, identify procedures with high complication rates, and examine predictive risk factors. METHODS: A retrospective analysis of the 2012 to 2016 American College of Surgeons National Surgical Quality Improvement Program plastic surgery data set was conducted. Complication rates were calculated for the entire cohort and each procedure therein. Microsurgical procedures were analyzed as a subgroup, where multivariate logistic regression models determined the risk factors for surgical site infection (SSI) and related reoperation. RESULTS: We identified 108 303 patients undergoing a plastic surgery procedure of which 6 264 (5.78%) experienced ≥1 complication. The outcome with the highest incidence was related reoperation (3.31%), followed by SSI (3.11%). Microsurgical cases comprised 6 148 (5.68%) of all cases, and 1211 (19.33%) experienced ≥1 complication. Similar to the entire cohort, the related reoperation (12.83%) and SSI (5.66%) were common complications. Increased operative time was a common independent risk factor predictive of a related reoperation or development of an SSI (P < 001). Of all microsurgeries, 23.3% had an operative time larger than 10 hours which lead to faster increase in reoperation likelihood. CONCLUSIONS: The complication rate in plastic surgery remains relatively low but is significantly increased for microsurgery. Increased operative time is a common risk factor. Two-team approaches and staged operations could be explored, as a large portion of microsurgeries are vulnerable to increased complications.


HISTORIQUE: Les données à grande échelle sur les complications de la chirurgie plastique font défaut. Une description des taux de référence et des résultats cliniques des patients permettrait de mieux déterminer comment améliorer les soins aux patients et réaliser des économies dans les systèmes de santé. Dans le présent article, les chercheurs recensent les complications les plus fréquentes en chirurgie plastique, dégagent les interventions aux taux de complication élevés et examinent les facteurs de risque prédictifs. MÉTHODOLOGIE: Les chercheurs ont réalisé une analyse rétrospective des données de chirurgie plastique tirées du programme national d'amélioration de la qualité chirurgicale de l'American College of Surgeons entre 2012 et 2016. Ils ont calculé les taux de complications de toute la cohorte et de chaque intervention recensée. Ils ont analysé les interventions microchirurgicales en sous-groupe, où ils ont utilisé des modèles de régression logistique multivariée pour déterminer les facteurs de risque d'infection des plaies opératoires (IPO) et de réopérations s'y rapportant. RÉSULTATS: Les chercheurs ont dénombré 108 303 patients qui avaient subi une intervention en chirurgie plastique, dont 6 264 (5,78 %) avaient souffert d'au moins une complication. Les réopérations (3,31 %), suivies des IPO (3,11 %) étaient les résultats à la plus forte incidence. Les cas de microchirurgie représentaient 6 148 (5,68 %) de toutes les occurrences, et 1211 (19,33 %) ont souffert d'au moins une complication. Tout comme dans l'ensemble de la cohorte, les réopérations (12,83 %) et les IPO (5,66 %) étaient des complications courantes. La plus longue durée de l'opération était un facteur de risque indépendant fréquent, prédicteur d'une réopération ou d'une IPO (p<0,001). Ainsi, 23,3 % des microchirurgies duraient plus de dix heures, ce qui s'associait à une plus forte augmentation du risque de réopération. CONCLUSIONS: Le taux de complications demeure relativement faible en chirurgie plastique, mais est significativement plus élevé en microchirurgie. La longue durée des opérations représente un facteur de risque courant. On pourrait explorer les approches à deux équipes et les opérations échelonnées, car une forte proportion des microchirurgies sont vulnérables à un accroissement des complications.

9.
Acad Emerg Med ; 26(8): 856-866, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31317606

RESUMEN

BACKGROUND: Pay-for-performance (P4P) programs have been implemented in various forms to reduce emergency department (ED) patient length of stay (LOS). This retrospective study investigated to what extent the timing of patient disposition in Metro Vancouver EDs was influenced by a LOS-based P4P program. METHODS: We analyzed ED visit records of four major hospitals in Metro Vancouver, Canada. For each ED, we individually tested whether LOS was distributed discontinuously at the LOS target before and after the P4P program was terminated. For the P4P effective period, we examined whether patients discharged just prior to the LOS target had a higher 7-day return-and-admission (RA) rate-the probability that a patient, after being discharged home, returned to any ED within 7 days and was admitted to an inpatient unit-than patients discharged just after the target. RESULTS: Prior to the termination of the P4P program, in all four EDs, the LOS density of admitted patients was discontinuous and had a significant drop at the P4P 10-hours admission LOS target; a similar phenomenon was observed among discharged patients at the 4-hours discharge LOS target, but only in the two lower-volume EDs. Furthermore, in a lower-volume ED, patients who were discharged right before the 4-hours P4P LOS target had a higher 7-day RA rate than patients discharged right after the LOS target. After the termination of the discharge incentive, the discontinuity at the discharge LOS target became less evident, but patients were still more frequently admitted just before 10 hours in three of the four EDs as the local health authority continued to support the admission incentive scheme after the government terminated the P4P program. CONCLUSIONS: The LOS-based financial incentive scheme appears to have influenced the timing of ED patient dispositions. The results suggest mixed consequences of the P4P program-it can reduce access block for admitted patients but may also lead to discharges associated with return visits and admissions.


Asunto(s)
Servicio de Urgencia en Hospital/economía , Tiempo de Internación/estadística & datos numéricos , Alta del Paciente/estadística & datos numéricos , Reembolso de Incentivo/economía , Adulto , Colombia Británica , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Humanos , Tiempo de Internación/economía , Masculino , Persona de Mediana Edad , Alta del Paciente/economía , Estudios Retrospectivos
10.
Nanoscale ; 10(30): 14525-14533, 2018 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-30024014

RESUMEN

We demonstrate the deposition of mechanically robust UV-absorbing nanocomposite coatings with a newly developed dual-source deposition method involving ultrasonic spraying and open-air plasma deposition. Nanoparticles and the coating matrix are independently deposited which eliminates difficulties associated with preparing composites with high mass fraction of well-dispersed nanoparticles in the matrix. Nanocomposite coatings containing different concentrations of silica, ceria, and both titania and ceria nanoparticles were successfully deposited with good nanoparticle dispersity, high transparency over the visible range, effective absorption in the UV wavelength, and enhanced mechanical properties. Moreover, films were successfully deposited on several substrates including polycarbonate to demonstrate the low processing temperature of this dual-source deposition method. Coatings with different nanoparticle concentrations and film thicknesses were systematically studied in terms of their surface morphology, optical properties and mechanical properties. Accelerated photostability testing of the UV-absorbing nanocomposites demonstrates significantly enhanced performance compared to existing coatings with either a polymeric matrix or organic UV-absorbers.

11.
ACS Nano ; 12(6): 5495-5503, 2018 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-29882658

RESUMEN

We report on a sustainable route to protective nanocomposite coatings, where one of the components, nanocellulose fibrils, is derived from trees and the glass matrix is an inexpensive sol-gel organic-inorganic hybrid of zirconium alkoxide and an epoxy-functionalized silane. The hydrophilic nature of the colloidal nanocellulose fibrils is exploited to obtain a homogeneous one-pot suspension of the nanocellulose in the aqueous sol-gel matrix precursors solution. The mixture is then sprayed to form nanocomposite coatings of a well-dispersed, random in-plane nanocellulose fibril network in a continuous organic-inorganic glass matrix phase. The nanocellulose incorporation in the sol-gel matrix resulted in nanostructured composites with marked effects on salient coating properties including optical transmittance, hardness, fracture energy, and water contact angle. The particular role of the nanocellulose fibrils on coating fracture properties, important for coating reliability, was analyzed and discussed in terms of fibril morphology, molecular matrix, and nanocellulose/matrix interactions.

12.
ACS Appl Mater Interfaces ; 9(48): 42217-42224, 2017 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-29135222

RESUMEN

Polymer networks are extensively utilized across numerous applications ranging from commodity superabsorbent polymers and coatings to high-performance microelectronics and biomaterials. For many applications, desirable properties are known; however, achieving them has been challenging. Additionally, the accurate prediction of elastic modulus has been a long-standing difficulty owing to the presence of loops. By tuning the prepolymer formulation through precise doping of monomers, specific primary network defects can be programmed into an elastomeric scaffold, without alteration of their resulting chemistry. The addition of these monomers that respond mechanically as primary defects is used both to understand their impact on the resulting mechanical properties of the materials and as a method to engineer the mechanical properties. Indeed, these materials exhibit identical bulk and surface chemistry, yet vastly different mechanical properties. Further, we have adapted the real elastic network theory (RENT) to the case of primary defects in the absence of loops, thus providing new insights into the mechanism for material strength and failure in polymer networks arising from primary network defects, and to accurately predict the elastic modulus of the polymer system. The versatility of the approach we describe and the fundamental knowledge gained from this study can lead to new advancements in the development of novel materials with precisely defined and predictable chemical, physical, and mechanical properties.

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