RESUMO
The increasing public demand for fresh products has catalyzed the requirement for cold chain logistics distribution systems. However, challenges such as temperature control and delivery delays have led a significant product loss and increased costs. To improve the current situation, a novel approach to optimize cold chain logistics distribution for fresh products will be presented in the paper, utilizing a hybrid Tabu-Grey wolf optimizer (TGWO) algorithm. The proposed hybrid approach combines Tabu search (TS) and Grey wolf optimizer (GWO), employing TS for exploration and GWO for exploitation, aiming to minimize distribution costs in total and establish efficient vehicle scheduling schemes considering various constraints. The effectiveness of the TGWO algorithm is demonstrated through experiments and case studies compared to other heuristic algorithms. Comparative analysis against traditional optimization methods, including Particle swarm optimization (PSO), Whale optimization algorithm (WOA), and original GWO, highlights its superior efficiency and solution quality. This study contributes theories by demonstrating the efficacy of hybrid optimization techniques in complex supply chain networks and dynamic market environments. The practical implication lies in the implementation of TGWO to bolster distribution efficiency, cost reduction, and product quality maintenance throughout the logistics process, offering valuable insights for operational and strategic improvements by decision-makers. However, the study has limitations in generalizability and assumptions, suggesting future research areas including exploring new search operators, applying additional parameters, and using the algorithm in diverse real-life scenarios to improve its effectiveness and applicability.
Assuntos
Algoritmos , Refrigeração/métodosRESUMO
Time-temperature data for queso fresco (QF) cheese varieties stored in a residential refrigerator operating at 5°C and a predictive microbiology secondary model for Listeria monocytogenes in QF were used to estimate a refrigerator performance indicator (RPI) of microbial preservation. RPI values were used to assess how compressor technology (single [SS] and variable speed [VS]), ambient temperature (21.1°C [LT] and 32.2°C [HT]), and refrigerator load (22.5 kg regular load and 39 kg higher load) affected preservation performance. All deterministic and probabilistic RPI estimations slightly exceeded the desirable 1.0 value, i.e., the variable temperatures for the QF kept in the refrigerator were worse than keeping it constantly at the temperature recommended by food safety agencies for QF. Furthermore, the mean comparison of estimates of the time-temperature equivalent indicator previously developed by French researchers showed similar behavior to those observed for RPI. Finally, statistical analysis showed that Tambient was the factor with the highest impact on refrigerator performance because of its impact on the sample temperature increase during door openings and when exposed to ambient temperature during product use. This highlights the need to reduce the time for product temperature recovery by improving the compressor operation logic. Also important are consumer behavior changes such as a reduction in product exposure to ambient temperature and in the door opening duration and frequency. PRACTICAL APPLICATION: This study demonstrated how a quantitative tool (RPI) can assess refrigerator preservation performance. Although the findings presented can be applied to any cold chain segment, the data used was collected for its weakest link, the domestic refrigerator. Surveys show that 77% of them operate above the recommended 4°C. The RPI methodology is ready for use by refrigerator designers to assess performance improvements possible by modifications of the compressor operation logic. Moreover, it can be integrated into smart-hubs monitoring the frequency and duration of refrigerator door openings to inform consumers when their habits are compromising the preservation performance of the refrigerator.
Assuntos
Queijo , Microbiologia de Alimentos , Conservação de Alimentos , Listeria monocytogenes , Refrigeração , Refrigeração/métodos , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/isolamento & purificação , Microbiologia de Alimentos/métodos , Conservação de Alimentos/métodos , Queijo/microbiologia , Temperatura , Fatores de Tempo , Armazenamento de Alimentos/métodos , Contagem de Colônia Microbiana/métodosRESUMO
INTRODUCTION: The United States Army has shifted doctrine to focus on large-scale combat operations against peer to near-peer adversaries. Future conflicts could result in a limited supply chain, leaving medical providers with only expired blood products for treatment of hemorrhagic shock. This study evaluated quality, function, and safety metrics of whole blood stored for 1 week past regulated expiration (i.e., 35 days, in CPDA-1). MATERIALS AND METHODS: Whole blood units (n = 6) were collected in citrate phosphate dextrose adenine-1 (CPDA-1) anticoagulant and stored refrigerated for up to 42 days. Units were sampled on days 35, 37, 39, and 42 of storage and evaluated for the following: complete blood count, blood metabolism and chemistries, clotting dynamics, and presence of bacteria. RESULTS: The majority of evaluated parameters fell outside of normal clinical ranges beginning at day 35 of storage. At 42 days, blood pH was 6.58 ± 0.038, hemolysis was significantly increased (P = .037 vs day 35), and bacterial contamination was not evident. Glucose levels continuously dropped during extended storage. K+ was significantly increased at day 42 compared to day 35 (P = .010). A significant reduction in clot strength, factor V activity, and factor VIII activity was evident beginning at day 39 of storage. CONCLUSIONS: Storage of whole blood out to 42 days results in a continuous decline in function, but further in vivo safety studies should be performed to determine if the benefits of expired blood outweigh the risks. Other methods to safely extend storage of whole blood that maintain hemostatic function and preserve safety should be investigated, with emphasis placed on methods that reduce potassium leak and/or hemolysis.
Assuntos
Preservação de Sangue , Humanos , Preservação de Sangue/métodos , Preservação de Sangue/normas , Refrigeração/métodos , Refrigeração/normas , Fatores de Tempo , Hemostasia/fisiologiaAssuntos
Criopreservação , Congelamento , Refrigeração , Gerenciamento do Tempo , Criopreservação/economia , Criopreservação/instrumentação , Criopreservação/métodos , Refrigeração/economia , Refrigeração/instrumentação , Refrigeração/métodos , Gerenciamento do Tempo/economia , Gerenciamento do Tempo/métodosRESUMO
Home preservation depends on the food matrix, refrigerator design/technology, consumer actions, and ambient temperature. Storing different food matrices in product-relevant refrigerator locations generating different temperature histories can be used to develop an indicator of how refrigerator technology, consumer habits, and environment conditions impact the refrigerator food preservation performance. In this study, poultry, particularly prone to spoilage reflecting its pH, nutrient availability, and high aw, was used to evaluate refrigerator preservation performance as affected by compressor technology (single [SS] and variable speed [VS]), ambient temperature (21.1°C [LT] and 32.2°C [HT]), and refrigerator load (22.5 kg [RL] and 39 kg [HL]). Time-temperature values collected for chicken breast stored in a drawer independently controlled at 0°C in a refrigerator set 5°C, and a Pseudomonas predictive microbiology model, were used to estimate a normalized refrigerator performance indicator (RPI). Values <1, â¼1, and >1 described excellent, good, or poor performance, respectively. A first analysis revealed that up to 54% of chicken breast temperatures were above its recommended refrigerated storage value. When ignoring variability sources, SS technology yielded RPI values ranging 0.61-0.70, whereas the more energy efficient VS compressor yielded values ranging 0.86-1.14. The higher and wider VS RPI range reflects a compressor control logic optimized for energy efficiency compliance while disregarding effects on food preservation. When considering the variability of model parameters and temperature measurements through one-sided 95% confidence intervals yielded RPI reaching 1.16. Although the independently controlled drawer preservation performance was near optimal, it can improve by considering energy use and preservation impact when optimizing the compressor speed control protocol. PRACTICAL APPLICATION: Worldwide poultry meat consumption has reached 15 kg per person. Refrigeration is widely used for its safety and quality preservation. Efficiency regulations decreased the energy use of residential refrigerators by nearly tenfold even though their size increased by 50% in the last half century. In this study, we provide quantitative evidence that their preservation performance must be improved. This is particularly true for upper end units typically equipped with quieter and more energy-efficient variable speed compressors. The same methodology can be used to evaluate the preservation performance of the storage units, trucks, and display cases used for refrigerated products.
Assuntos
Galinhas , Refrigeração , Animais , Temperatura , Refrigeração/métodos , Conservação de Alimentos/métodos , Microbiologia de AlimentosRESUMO
European Union regulations stipulate that household refrigeration systems must operate with fluid refrigerants that possess low global warming potential (GWPs). In this work, theoretical performance of six binary and one ternary mixture (which consists of R13I1, R290, R161, R32, R1234yf, and R1234ze(E)) was investigated. The performance parameters such as coefficient of performance (COP), refrigeration effect (RE), volumetric cooling capacity (VCC), discharge temperature, pressure ratio, and specific power consumption of all considered refrigerant mixtures is studied with respect to the evaporator temperature range of -18 to 180C and the condenser temperature range of 40 to 550C. The properties corresponding to different operating conditions for the refrigerants considered in this study are estimated using REFPROP 10. The findings demonstrated that, when compared to R134a, all the investigated refrigerants exhibited very low specific power consumption (apart from M9, M10, and M14-M16), and high volumetric cooling capacity (VCC) (apart from M11 and M13) under the operating conditions of evaporator temperature -180C and condenser temperature 400C. M1-M3 and M11-M13 gave similar and within 10% deviation in coefficient of performance, while M3 and M11-M13 refrigerant mixtures offer significantly low discharge temperatures when compared to R134a. Refrigerant mixtures M2 and M11 consistently exhibited a better performance in comparison to R134a in the aspect of majority of the performance parameters considered in this study. Finally, it is understood that M2 and M11 are two possible alternative refrigerants to conventional refrigerants used in small refrigeration units (R134a and R22). Further, it is also identified that these mixtures are non-flammable, possess zero ODP and low GWP values.
Assuntos
Temperatura Baixa , Refrigeração , Refrigeração/métodos , Temperatura , Aquecimento Global , Transição de FaseRESUMO
The changes in microbiological, physiochemical, and textural properties in fresh cheeses made from either cow or goat milk were observed under hyperbaric storage (HS, 50-100 MPa) at room temperature (RT) and compared with refrigerated storage under normal atmospheric pressure for 60 days. An initial microbial growth inhibition was observed for both cheese types, as well as a considerable inactivation of all endogenous microbiota under HS/RT (75-100 MPa/RT). This contributed to a higher stability of pH and color values, especially at the higher pressure at room temperature (100 MPa/RT) throughout 60 days storage. A compression effect occurred during HS/RT, resulting in higher whey loss, reduction in moisture content, and textural changes. Such changes tended to decrease over time, to values closer to the initial ones, with hardness values at the 60th day of storage at 75/RT similar to those observed for refrigeration on the 7th day and 1.4-fold higher than those observed at 100/RT. Overall, HS/RT reduced the microbial populations load during storage (≥5 log units in some cases), with minimal effects on most of the evaluated quality parameters. These results point to a considerable shelf-life extension of HS fresh cheeses, without temperature control, pinpointing HS as a more sustainable preservation strategy than refrigeration, with great potential for industrial application. PRACTICAL APPLICATION: The results presented in this study point to increased microbial stability of fresh cheeses when stored under hyperbaric storage without temperature control, leading possibly to an increased shelf-life, of up to 60 days. This kind of new food preservation strategy may be suitable for longer transportation of foods, where energy may not be handily and widely available, while additionally contributing to increased shelf-life and safety. Also, hyperbaric storage could be applied throughout the food storage, improving shelf-life with a lower carbon footprint than refrigeration.
Assuntos
Queijo , Temperatura , Armazenamento de Alimentos/métodos , Conservação de Alimentos/métodos , Refrigeração/métodosRESUMO
High pressure pasteurised (HPP) milk was stored by hyperbaric storage at room temperature (HS/RT) (50-100 MPa at 20 °C) and compared with refrigeration (RF), to assess the effect on two pathogens surrogates and a pathogenic, up to 120 days, and on fatty acids, volatile organic compounds (VOCs) and secondary lipid oxidation over 60 days. HS/RT (75-100 MPa) was able to inactivate at least 6.68/6.31/6.03 log CFU/mL of Escherichia coli/Listeria innocua/Salmonella Senftenberg (to below the detection limit), while RF resulted only in minor changes. Overall, fatty acids profile remained stable under HS/RT, although secondary lipid oxidation showed slightly higher values. In addition, both HS/RT and RF showed stable and similar VOCs profiles and off-flavour indicative compounds were not detected, except for the lowest pressure (50 MPa) after 40 days. HS/RT preserved HPP milk with enhanced microbial safety, shelf-life and quality compared to RF, being in addition quasi-energetically costless and more sustainable than RF.
Assuntos
Leite , Refrigeração , Animais , Ácidos Graxos/análise , Ácidos Graxos Voláteis , Conservação de Alimentos/métodos , Leite/química , Refrigeração/métodos , TemperaturaRESUMO
The effect of extended refrigerated storage of 14 serum and plasma specimens on 5 syphilis serologic tests was evaluated for 16 weeks. Higher stability of nontreponemal and treponemal antibodies in serum was recorded compared to plasma. Described work may provide insights on refrigerated specimens' stability and suitability for syphilis tests.
Assuntos
Anticorpos Antibacterianos/análise , Anticorpos Antibacterianos/sangue , Refrigeração/métodos , Manejo de Espécimes/métodos , Sorodiagnóstico da Sífilis/métodos , Sífilis/sangue , Sífilis/diagnóstico , Sífilis/microbiologia , Humanos , Plasma/microbiologia , Soro/microbiologiaRESUMO
Commercially harvested cull dairy cow carcasses (n = 64) from the two lowest-valued marketing classes (MC: Lean, LE; Light, LI) were conventionally chilled (CN) or vascularly rinsed with a chilled isotonic substrate solution (Rinse & Chill®; RC). Longissimus lumborum (LL) and Triceps brachii (TB) muscles were processed (steaks, ground). Early postmortem (first 24 h), RC resulted in a lower pH at each time measured. RC steaks had longer sarcomeres and lower shear force than CN. RC produced greater redness associated with blooming and display times. RC LE beef resulted in greater oxymyoglobin during display times. RC ground TB had greater moisture fat-free than CN. RC Lean LL had less purge loss compared to CN LE. RC had greater total pigments than CN. RC ground TB had greater oxygen consumption and lower thiobarbituric acid reactive substances compared to CN. RC has the potential to improve tenderness and color as well as limit lipid oxidation with similar benefits across the two marketing classes.
Assuntos
Manipulação de Alimentos/métodos , Qualidade dos Alimentos , Carne Vermelha/análise , Animais , Bovinos , Feminino , Concentração de Íons de Hidrogênio , Músculo Esquelético/química , Mioglobina/análise , Carne Vermelha/classificação , Refrigeração/métodos , Resistência ao Cisalhamento , Substâncias Reativas com Ácido TiobarbitúricoRESUMO
INTRODUCCIÓN: El presente documento de evaluación de tecnología sanitaria (ETS) expone la evaluación de la eficacia y seguridad del equipo de hipotermia terapéutica de cuerpo completo (HTCC) con mantas térmicas en comparación al tratamiento de soporte estándar en la unidad de cuidados intensivos neonatales (UCIN) en recién nacidos de 35 semanas o más con asfixia perinatal (AP) y encefalopatía hipóxico-isquémica (EHI) moderada o severa sin malformaciones congénitas mayores, cromosomopatías incompatibles con la vida, retardo en crecimiento intrauterino severo (<1,8 kg), patologías quirúrgicas severas, o con criterios de severidad (bradicardia mantenida, midriasis paralítica, ausencia de reflejo corneal). La encefalopatía neonatal es un estado de alteración de la función neurológica del recién nacido. Esta patología se asocia a convulsiones y dificultad para iniciar o mantener la respiración; acarreando una alta morbilidad y mortalidad neonatal. La encefalopatía hipóxico-isquémica (EHI), producida por un cuadro de asfixia perinatal (AP), es uno de los principales subtipos de encefalopatía neonatal. En el Perú, un informe de la Dirección de Epidemiología del Ministerio de Salud reportó que la AP fue la tercera causa de muerte neonatal entre los años 2011 y 2012. Además, reportes del servicio de neonatología del Hospital Nacional Edgardo Rebagliati Martins (HNERM) del periodo 2015 - 2016 estimaron la incidencia de EHI en 2.5 casos por cada 1000 nacidos vivos. Diversos estudios han reportado que la neuroprotección mediante la hipotermia terapéutica (HT) disminuye la morbilidad y mortalidad en neonatos con EHI moderada o severa. Para la inducción de HT se utilizan, principalmente, dos tecnologías: 1) la HT de cuerpo completo (HTCC) y 2) la HT selectiva de cabeza (HTSC). Las unidades de cuidados intensivos neonatales (UCIN) de EsSalud brindan terapia de soporte a los recién nacidos con EHI consistente en monitoreo de signos vitales y atención oportuna frente a disfunciones orgánicas, además de reducción de la temperatura mediante el apagado de calefactor en la incubadora, pero no cuentan con equipos específicos que aseguren que el neonato alcance temperaturas de enfriamiento óptimas. Por ello, los especialistas en neonatología del HNERM solicitan la incorporación de la tecnología de HTCC con mantas térmicas con la finalidad de disminuir la mortalidad y discapacidad severa de los neonatos con EHI moderada o severa. En este sentido, el objetivo del presente dictamen preliminar fue evaluar la eficacia y seguridad de la hipotermia terapéutica de cuerpo completo con mantas térmicas en recién nacidos de 35 semanas o más con asfixia perinatal y encefalopatía hipóxico-isquémica moderada o severa. METODOLOGÍA: Se realizó una búsqueda sistemática para identificar la evidencia disponible a abril de 2021 sobre la eficacia y seguridad del procedimiento de hipotermia terapéutica de cuerpo completo en recién nacidos de 35 semanas o más con asfixia neonatal y encefalopatía hipóxico-isquémica moderada o severa. Se indagó en las bases de datos PubMed, Cochrane Library y LILACS (Literatura Latinoamericana y del Caribe en Ciencias de la Salud) y se creó una alerta semanas en PubMed que informara si surgiera nueva evidencia sobre el tema. Adicionalmente, se realizó una búsqueda manual de literatura gris mediante el motor de búsqueda Google. Se buscaron GPC y ETS que pudieran haber sido omitidas en la revisión sistemática por no encontrarse indixadas en las bases de datos consultadas. De igual forma, se consultaron las páginas oficiales de grupos conocidos por realizar ETS y GPC que incluyó el National Institute for Health and Care Excellence (NICE), la Canadian Agency for Drugs and Technologies in Health (CADTH), la Haute Autorité de Santé (HAS), el Institut für Qualitát und Wirtschaftlichkeit im Gesundheitswesen (IQWiG) y la Base Regional de Informes de Evaluación de Tecnologías en Salud de las Américas (BRISA), además de sociedades especializadas en manejo de pacientes pediátricos con patologías perinatales (sociedad británica de medicina perinatal (BAPM), la asociación americana del corazón, y la sociedad canadiense de pediatría). RESULTADOS: La presente sinopsis describe la evidencia disponible sobre la eficacia y seguridad de la HTCC con mantas térmicas en recién nacidos de 35 semanas o más con AP y EHI moderada o severa, según el tipo de publicación. CONCLUSIONES: El objetivo del presente dictamen preliminar es evaluar la eficacia y seguridad de la hipotermia terapéutica de cuerpo completo con mantas térmicas en recién nacidos de 35 semanas o más de gestación, con asfixia perinatal y encefalopatía hipóxico-isquémica moderada o severa. Se identificaron seis GPC American Heart Association (AHA), 2020; Ministerio de Salud Pública del Ecuador (MSP), 2019; Canadian Paediatric Society (CPS), 2018; Instituto Mexicano del Seguro Social (IMSS), 2017; Ministerio de Sanidad, Servicio Social e Igualdad de España (MSSSI), 2015; y Ministerio de Salud y Protección Social de Colombia (MinSalud), 2013) y siete publicaciones de cuatro ensayos clínicos aleatorizados (ECA) (HELIX: Thayyil et al., 2021; TOBY: Azzopardi et al., 2014, 2009; NICHD: Shankaran et al., 2012, 2008, 2005; y neo.nEURO.network: Simbruner et al., 2010). No existe evidencia de una mayor eficacia en el uso de HTCC frente a la HTSC. Pese a ello, en centros asistenciales que no han implementado aún un método de HT, las recomendaciones de las GPC indican que debería implementarse equipos de HTCC debido a su facilidad de uso, menor costo y facilidad de acceso para la utilización de otros equipos como el electroencefalograma. Entre las GPC, existe un consenso en que la aplicación de HTCC debe realizarse bajo protocolos similares a los utilizados en los principales ECA. La eficacia de la HTCC con mantas térmicas en infantes de 36 semanas o más de gestación con EIH moderada a severa es consistente en cuanto a la reducción de morbilidad, pero no en mortalidad. Los ECA más grandes en el tema han reportado beneficios clínicos, tanto en indicadores de desarrollo mental y psicomotor, como en ocurrencia de parálisis cerebral a los 18 - 22 meses y 6 - 7 años de vida. Pese a que uno de los ECA evaluados (HELIX) reporta mayor riesgo de muerte y ocurrencia de eventos adversos en los pacientes intervenidos con HTCC, esto se puede explicar debido a factores poblacionales que modificaron el efecto de la intervención. Por lo expuesto, el IETSI aprueba el uso de equipos de HTCC con mantas térmicas en recién nacidos de 36 semanas o más de edad gestacional, con AP y EHI moderada o severa, según lo establecido en el Anexo N°1. Debido a la falta de evidencia, no se aprueba su uso en recién nacidos con menos de 36 semanas de edad gestacional. La vigencia del presente dictamen preliminar es de un año a partir de la fecha de publicación.
Assuntos
Humanos , Recém-Nascido , Asfixia Neonatal/terapia , Refrigeração/métodos , Hipóxia-Isquemia Encefálica/terapia , Calefação/métodos , Hipotermia Induzida/métodos , Eficácia , Análise Custo-BenefícioRESUMO
Salmonella Typhimurium is a human pathogen associated with eggs and egg-derived products. In Australia, it is recommended that eggs should be refrigerated to prevent condensation that can enhance bacterial penetration across the eggshell. Except for the United States, the guidelines on egg refrigeration are not prescriptive. In the current study, in-vitro and in-vivo experiments were conducted to understand the role of egg storage temperatures (refrigerated vs ambient) on bacterial load and the virulence genes expression of Salmonella Typhimurium. The in-vitro egg study showed that the load of Salmonella Typhimurium significantly increased in yolk and albumen stored at 25 °C. The gene expression study showed that ompR, misL, pefA, spvA, shdA, bapA, and csgB were significantly up-regulated in the egg yolk stored at 5 °C and 25 °C for 96 h; however, an in-vivo study revealed that mice infected with egg yolk stored at 25 °C, developed salmonellosis from day 3 post-infection (p.i.). Mice fed with inoculated egg yolk, albumen, or eggshell wash stored at refrigerated temperature did not show signs of salmonellosis during the period of the experiment. Data obtained in this study highlighted the importance of egg refrigeration in terms of improving product safety.
Assuntos
Ovos/microbiologia , Inocuidade dos Alimentos/métodos , Refrigeração/métodos , Intoxicação Alimentar por Salmonella/prevenção & controle , Infecções por Salmonella/prevenção & controle , Salmonella typhimurium/patogenicidade , Animais , Austrália , Galinhas , Contagem de Colônia Microbiana , Feminino , Microbiologia de Alimentos , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Intoxicação Alimentar por Salmonella/microbiologia , Intoxicação Alimentar por Salmonella/patologia , Infecções por Salmonella/microbiologia , Infecções por Salmonella/patologia , Salmonella typhimurium/genética , Salmonella typhimurium/crescimento & desenvolvimento , Temperatura , VirulênciaRESUMO
The coexistence of field-induced blockage of the magnetization and significant magnetocaloric effects in the low-temperature region occurs in a mononuclear holmium(III) diethylenetriamine-N,N,N',Nâ³,Nâ³-pentaacetate complex, whose gadolinium(III) analogue is a commercial MRI contrast agent. Both properties make it a suitable candidate for cryogenic magnetic refrigeration, thus enlarging the variety of applications of this simple class of multifunctional molecular nanomagnets.
Assuntos
Complexos de Coordenação/química , Hólmio/química , Imãs/química , Ácido Pentético/química , Refrigeração/métodos , Temperatura Baixa , Fenômenos MagnéticosAssuntos
Diabetes Mellitus/tratamento farmacológico , Armazenamento de Medicamentos/métodos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Refrigeração/métodos , Campos de Refugiados , Diabetes Mellitus/epidemiologia , Armazenamento de Medicamentos/normas , Humanos , Hipoglicemiantes/normas , Insulina/normas , Refrigeração/normas , Campos de Refugiados/normasRESUMO
PURPOSE: To determine how early body refrigeration affects corneal donor transplant suitability and endothelial cell density. METHODS: Donor information was obtained from the CorneaGen Eye Bank including demographics, time of death to preservation, and body refrigeration status, for donors between 2012 and 2016. The death to preservation interval was classified into 3 categories: 0 to 10, 10 to 20, and 20+ hours. Two primary logistic method models were fit using a main effects model and an interaction model to determine the association of body refrigeration on unsuitability of transplantation and endothelial cell density. RESULTS: Analysis was from 42,929 donor eyes, with a mean (standard deviation) endothelial cell count of 2743 (415) cells/mm2. Fifty-nine percent of donor eyes were from male donors in the eye bank data set, and the mean death to preservation interval was 11.0 (5.6) hours for all eyes. Unsuitability for transplantation demonstrated a reduced adjusted odds ratio by 22% (OR = 0.78, P = 0.009) when the body was refrigerated during the death to preservation interval versus when the body was not refrigerated. Eyes that were refrigerated, however, exhibited no statistically significant difference in endothelial cell count from eyes that were not refrigerated (P = 0.12). CONCLUSIONS: We demonstrate an appreciable effect of early body refrigeration on transplant suitability in this large cohort of eye bank eyes. There was no beneficial effect of body refrigeration on endothelial cell count.
Assuntos
Transplante de Córnea/métodos , Endotélio Corneano/citologia , Bancos de Olhos , Preservação de Órgãos/métodos , Refrigeração/métodos , Contagem de Células , Endotélio Corneano/transplante , Feminino , Seguimentos , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Hyperbaric storage at room temperature (HS/RT: 75 MPa/25 °C) of vacuum-packaged fresh Atlantic salmon (Salmo salar) loins was studied for 30 days and compared to atmospheric pressure at refrigerated temperatures (AP/5 °C, 30 days) and RT (AP/25 °C, 5 days). Most of the fatty acids were not affected by storage conditions, with only a slight decrease of docosahexaenoic acid (DHA) content (n-3 polyunsaturated fatty acid) for AP samples, reflected in the lower polyene index values obtained and higher oxidation extent. For HS, a lower lipid oxidation extension and a slower increase of myofibrillar fragmentation index values were observed, when compared to AP samples. The volatile profile was similar for the HS and fresh samples, with the HS samples retaining fresh-like alcohols and aldehydes components, which disappeared in AP samples, mainly in AP/25 °C samples. The volatile profile for AP samples (5 and 25 °C) revealed mostly spoilage-like compounds due to microbial activity. Drip loss increased progressively during the 30 days of storage under HS, while a slight decrease of water holding capacity after 5 days was observed, increasing further after 30 days. Regarding textural properties, only resilience was affected by HS, decreasing after 30 days. So, HS/RT could represent an interesting extended preservation methodology of fresh salmon loins, since allows retaining important physicochemical properties for at least 15 days, while refrigeration after 5 days showed already volatile spoilage-like compounds due to microbial activity. Furthermore, this methodology allows additional considerable energy savings when compared to refrigeration.
Assuntos
Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Carne/análise , Refrigeração/métodos , Animais , Oxirredução , Preservação Biológica/métodos , Salmo salar , Alimentos Marinhos , Temperatura , VácuoRESUMO
Listeria monocytogenes has caused outbreaks of foodborne illness from apples in the USA, and is also a major issue for regulatory compliance worldwide. Due to apple's significance as an important export product from New Zealand, we aimed to determine the effect of long-term, low-temperature sea-freight from New Zealand to the USA (July) and Europe (March-April), two key New Zealand markets, on the survival and/or growth of L. monocytogenes on fresh apples. Temperature and humidity values were recorded during a shipment to each market (USA and Europe), then the observed variations around the 0.5 °C target temperature were simulated in laboratory trials using open ('Scired') and closed ('Royal Gala' for the USA and 'Cripps Pink' for Europe) calyx cultivars of apples inoculated with a cocktail of 107-108 cells of seven strains of L. monocytogenes. Samples were analysed for L. monocytogenes quantification at various intervals during the simulation and on each occasion, an extra set was analysed after a subsequent 8 days at 20 °C. When both the sea-freight simulations concluded, L. monocytogenes showed 5 log reductions on the equatorial surface of skin of apples, but only about 2.5 log reduction for USA and about 3.3 log reduction for Europe in the calyx. Cultivar type had no significant effect on the survival of L. monocytogenes for both sea-freight simulations, either in the calyx or on the skin (P > 0.05). Most of the reduction in the culturable cells on the skin occurred during the initial 2 weeks of the long-term storage simulations. There was also no significant difference in the reduction of L. monocytogenes at 0.5 or 20 °C. No correlation was observed between firmness or total soluble solids and survival of L. monocytogenes. Because the inoculated bacterial log reduction was lower in the calyx than on the skin, it is speculated that the risk of causing illness is higher if contaminated apple cores are eaten. The result suggested that the international sea-freight transportation does not result in the growth of L. monocytogenes irrespective of time and temperature. The results of this study provide useful insights into the survival of L. monocytogenes on different apple cultivars that can be used to develop effective risk mitigation strategies for fresh apples during long-term, low-temperature international sea-freight transportation.
Assuntos
Manipulação de Alimentos/métodos , Listeria monocytogenes/isolamento & purificação , Malus/microbiologia , Refrigeração/métodos , Carga Bacteriana , Temperatura Baixa , Contagem de Colônia Microbiana , Europa (Continente) , Microbiologia de Alimentos/métodos , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Nova ZelândiaRESUMO
BACKGROUND: Platelets pose the greatest transfusion-transmitted infectious risk among blood products. Refrigeration of platelets can mitigate bacterial contamination and extend platelet shelf life. Implementation of pathogen reduction technologies (PRTs) at blood banks has become increasingly popular to protect against emerging and reemerging infectious diseases. In this study, we sought to evaluate the effects of Intercept PRT on platelets collected on different platforms and cold-stored for up to 21 days in plasma and platelet additive solution (PAS). METHODS: Double-dose apheresis platelets were collected with use of a Trima or Amicus system into either 100% plasma or 65% InterSol PAS/35% plasma and split equally between two bags. One bag served as control, while the other received Intercept PRT treatment. Bags were stored unagitated in the cold and evaluated on Days 1, 7, 14, and 21 to assess platelet metabolism, activation, aggregation, and clot formation and retraction. RESULTS: By Day 14 of storage, lactate levels reached approximately 13 mmol/L for all samples irrespective of Intercept treatment. Mean clot firmness dropped from the 62.2- to 67.5-mm range (Day 1) to the 28.4- to 51.3-mm range (Day 21), with no differences observed between groups. Clot weights of Intercept-treated Trima/plasma samples were significantly higher than control by Day 14 of storage (P = .004), indicating a reduced clot retraction function. Intercept treatment caused a higher incidence of plasma membrane breakdown in plasma-stored platelets (P = .0013; Trima/plasma Day 14 Control vs Intercept). CONCLUSIONS: Intercept treatment of platelets and subsequent cold storage, in plasma or PAS, results in comparable platelet metabolism platelets for up to 14 days of storage but altered clotting dynamics. Pathogen-reduced platelets with an extended shelf life would be beneficial for the deployed setting and would greatly impact transfusion practice among civilian transfusion centers.