Transcriptional signature of durable effector T cells elicited by a replication defective HCMV vaccine.

Human cytomegalovirus (HCMV) is a leading infectious cause of birth defects and the most common opportunistic infection that causes life-threatening diseases post-transplantation; however, an effective vaccine remains elusive. V160 is a live-attenuated replication defective HCMV vaccine that showed a 42.4% efficacy against primary HCMV infection among seronegative women in a phase 2b clinical trial. Here, we integrated the multicolor flow cytometry, longitudinal T cell receptor (TCR) sequencing, and single-cell RNA/TCR sequencing approaches to characterize the magnitude, phenotype, and functional quality of human T cell responses to V160. We demonstrated that V160 de novo induces IE-1 and pp65 specific durable polyfunctional effector CD8 T cells that are comparable to those induced by natural HCMV infection. We identified a variety of V160-responsive T cell clones which exhibit distinctive "transient" and "durable" expansion kinetics, and revealed a transcriptional signature that marks durable CD8 T cells post-vaccination. Our study enhances the understanding of human T-cell immune responses to V160 vaccination.

A conditionally replication-defective cytomegalovirus vaccine elicits potent and diverse functional monoclonal antibodies in a phase I clinical trial.

A conditionally replication-defective human cytomegalovirus (HCMV) vaccine, V160, was shown to be safe and immunogenic in a two-part, double-blind, randomized, placebo-controlled phase I clinical trial (NCT01986010). However, the specificities and functional properties of V160-elicited antibodies remain undefined. Here, we characterized 272 monoclonal antibodies (mAbs) isolated from single memory B cells of six V160-vaccinated subjects. The mAbs bind to diverse HCMV antigens, including multiple components of the pentamer, gB, and tegument proteins. The most-potent neutralizing antibodies target the pentamer-UL subunits. The binding sites of the antibodies overlap with those of antibodies responding to natural HCMV infection. The majority of the neutralizing antibodies target the gHgL subunit. The non-neutralizing antibodies predominantly target the gB and pp65 proteins. Sequence analysis indicated that V160 induced a class of gHgL antibodies expressing the HV1-18/KV1-5 germline genes in multiple subjects. This study provides valuable insights into primary targets for anti-HCMV antibodies induced by V160 vaccination.

Longitudinal complications associated with PEG: Rate and severity of 30-day and 1-year complications experienced by patients after primary PEG insertion.

BACKGROUND AND AIMS: Percutaneous Endoscopic Gastrostomy (PEG) feeding is utilised in patients with exceptionally poor oral intake but is associated with both short and long-term complications. This study reviews longitudinal PEG complications and compares key subgroups. METHODS: Single-centre retrospective observational study of all patients receiving PEG insertion between January 2016 and December 2018. RESULTS: 306 patients met the inclusion criteria. The mean age at insertion was 67 years. The majority were cared for in their own home (80.4%) by themselves or family (74.9%). 127 PEG tubes were inserted for dysphagia and 165 prophylactically prior to treatment for head and neck cancer. In the first 30 days 16.7% experienced a complication. The most frequently reported was peristomal pain (9.2%). In the first year, 35.6% experienced at least one complication, 12.4% two complications and 6.6% three complications and 6.5% required inpatient treatment for their complication. The most common was pain (14.4%) followed by site weeping, site infection and external overgranulation. Patients with dysphagia took longer to develop complications, had fewer complications and took longer to require management by members of the secondary care team than those with head and neck cancer. Discounting peristomal pain, there was no difference in total complications between patients caring for themselves when compared to those receiving professional input. CONCLUSION: One third of patients will experience a complication related to their PEG tube over 1 year, but the majority are managed in an outpatient setting. This study has implications for planning support services and consenting and counselling patients pre-PEG-insertion.

The Hidden Burden of Community Enteral Feeding on the Emergency Department.

BACKGROUND: Enteral feeding tubes are associated with their most serious complications in the days and weeks after insertion, but there are limited published data in the literature on late complications and the implications for the healthcare service. METHODS: This is a retrospective observational study of attendances to a UK hospital emergency department (ED), with enteral tube complications as the primary reason for attendance. RESULTS: Over 24 months, 139 attendances were recorded. Dislodged tubes and blocked tubes accounted for the majority of complications and subsequent admissions, with a mixture of enteral tube types being associated with both. Thirty-five percent of patients were admitted, and the average healthcare cost per attendance was $1071. CONCLUSION: Enteral tube complications can place a hidden burden on the patient, the ED, and healthcare costs. More work on education and supporting caregivers to resolve problems themselves could reduce the burden on busy EDs.

Survey of nurses' knowledge and practice regarding medication administration using enteral tubes.

AIM AND OBJECTIVES: To identify the practice variation of the individual practitioners in medications' formulation modification for patients using enteral feeding tubing and to support health practitioners involved in this process. BACKGROUND: Blockage of enteral tubes is a common problem that can sometimes be resolved but may require replacement of the tube. Medications are a common culprit. DESIGN: A survey of 73 registered nurses' practices around medication administration via enteral feeding tubes. METHODS: A questionnaire study was undertaken within a district general hospital across a broad variety of wards to explore nurses' experiences of medication administration via enteral tubes. The study is reported in accordance with the squire 2.0 guidelines from the EQUATOR network. RESULTS: Seventy-three nurses responded. Twenty-six per cent reported never checking about drug modification for administration via a tube, 12% check every time and 61% when unsure about a new drug. The volume of fluid flushes administered after medication ranged from 7.5-150 ml. Seventy-one per cent of participants reported stopping feed when medications are required, varying from 1-60 min. Sixty per cent had experienced a blocked tube and 52% the tube being removed for these reasons. The clinical nurse specialist was the commonest first point of call to help. Staff named 15 medications as the most problematic to administer, lactulose and omeprazole were the top two. CONCLUSIONS: Practice varies significantly amongst nurses around medication administration. Theoretically, this may contribute to blocked tubes and excessive fluid administration to some patients. Barriers to medication administration were thematically grouped into: time, difficulty modifying medication, medication interactions and knowledge. Areas identified to support staff include training, devices to crush medications, medication suitability, multidisciplinary approach to streamline care and quick reference guides. RELEVANCE TO CLINICAL PRACTICE: Health professionals may use these results to reduce and ultimately avoid problems with administering medications through feeding tubes. Organisations may use these results to develop their local practice pathways for prescribing, dispensing and training around administration of medications through enteral tubes. In a community setting, this paper may improve the awareness of patients, caregivers and prescribers of the possible implications of tubing blockages.

A Replication-Defective Human Cytomegalovirus Vaccine Elicits Humoral Immune Responses Analogous to Those with Natural Infection.

Human cytomegalovirus (HCMV) can cause congenital infections, which are a leading cause of childhood disabilities. Since the rate of maternal-fetal transmission is much lower in naturally infected (HCMV-seropositive) women, we hypothesize that a vaccine candidate capable of eliciting immune responses analogous to those of HCMV-seropositive subjects may confer protection against congenital HCMV. We have previously described a replication-defective virus vaccine based on strain AD169 (D. Wang, D. C. Freed, X. He, F. Li, et al., Sci Transl Med 8:362ra145, 2016, https://doi.org/10.1126/scitranslmed.aaf9387). The vaccine, named V160, has been shown to be safe and immunogenic in HCMV-seronegative human subjects, eliciting both humoral and cellular immune responses (S. P. Adler, S. E. Starr, S. A. Plotkin, S. H. Hempfling, et al., J Infect Dis 220:411-419, 2019, https://doi.org/10.1093/infdis/171.1.26). Here, we further showed that sera from V160-immunized HCMV-seronegative subjects have attributes similar in quality to those from seropositive subjects, including high-avidity antibodies to viral antigens, coverage against a panel of genetically distinct clinical isolates, and protection against viral infection in diverse types of human cells in culture. More importantly, vaccination appeared efficient in priming the human immune system, inducing memory B cells in six V160 recipients at frequencies comparable to those of three HCMV-seropositive subjects. Our results demonstrate the ability of V160 to induce robust and durable humoral memory responses to HCMV, justifying further clinical evaluation of the vaccine against congenital HCMV.IMPORTANCEIn utero HCMV infection can lead to miscarriage or childhood disabilities, and an effective vaccine is urgently needed. Since children born to women who are seropositive prior to pregnancy are less likely to be affected by congenital HCMV infection, it has been hypothesized that a vaccine capable of inducing an immune response resembling the responses in HCMV-seropositive women may be effective. We previously described a replication-defective virus vaccine that has been demonstrated safe and immunogenic in HCMV-seronegative subjects. Here, we conducted additional analyses to show that the vaccine can induce antibodies with functional attributes similar to those from HCMV-seropositive subjects. Importantly, vaccination can induce long-lived memory B cells at frequencies comparable to those seen in HCMV-seropositive subjects. We conclude that this vaccine is a promising candidate that warrants further clinical evaluation for prevention of congenital HCMV.

Thermal pasteurization of ready-to-eat foods and vegetables: Critical factors for process design and effects on quality.

Increasing consumer desire for high quality ready-to-eat foods makes thermal pasteurization important to both food producers and researchers. To be in compliance with the Food Safety Modernization Act (FSMA), food companies seek regulatory and scientific guidelines to ensure that their products are safe. Clearly understanding the regulations for chilled or frozen foods is of fundamental importance to the design of thermal pasteurization processes for vegetables that meet food safety requirements. This article provides an overview of the current regulations and guidelines for pasteurization in the U.S. and in Europe for control of bacterial pathogens. Poorly understood viral pathogens, in terms of their survival in thermal treatments, are an increasing concern for both food safety regulators and scientists. New data on heat resistance of viruses in different foods are summarized. Food quality attributes are sensitive to thermal degradation. A review of thermal kinetics of inactivation of quality-related enzymes in vegetables and the effects of thermal pasteurization on vegetable quality is presented. The review also discusses shelf-life of thermally pasteurized vegetables.

Effects of Peach Cultivar on Enzymatic Browning Following Cell Damage from High-Pressure Processing.

Peach cultivars contribute to unique product characteristics and may affect the degree of browning after high-pressure processing (HPP). Nine peach cultivars were subjected to HPP at 0, 100, and 400 MPa for 10 min. Proton nuclear magnetic resonance (1H NMR) relaxometry, light microscopy, color, polyphenol oxidase (PPO) activity, and total phenols were evaluated. The development of enzymatic browning during refrigerated storage occurred because of damage during HPP that triggered loss of cell integrity, allowing substrates to interact with enzymes. Increasing pressure levels resulted in greater damage, as determined by shifts in transverse relaxation time (T2) and by light micrographs. Discoloration was triggered by membrane decompartmentalization but limited by PPO activity, which was found to correlate to cultivar harvest time (early, mid, and late season). Outcomes from the microstructure, 1H NMR ,and PPO activity evaluation were an effective means of determining membrane decompartmentalization and allowed for prediction of browning scenarios.

The Impact of Maturity Stage on Cell Membrane Integrity and Enzymatic Browning Reactions in High Pressure Processed Peaches (Prunus persica).

Fruit maturity is an important factor associated with final product quality, and it may have an effect on the level of browning in peaches that are high pressure processed (HPP). Peaches from three different maturities, as determined by firmness (M1 = 50-55 N, M2 = 35-40 N, and M3 = 15-20 N), were subjected to pressure levels at 0.1, 200, and 400 MPa for 10 min. The damage from HPP treatment results in loss of fruit integrity and the development of browning during storage. Increasing pressure levels of HPP treatment resulted in greater damage, particularly in the more mature peaches, as determined by shifts in transverse relaxation time (T2) of the vacuolar component and by light microscopy. The discoloration of peach slices of different maturities processed at the same pressure was comparable, indicating that the effect of pressure level is greater than that of maturity in the development of browning.

High hydrostatic pressure as a method to preserve fresh-cut Hachiya persimmons: A structural approach.

The "Hachiya" persimmon is the most common astringent cultivar grown in California and it is rich in tannins and carotenoids. Changes in the microstructure and some physicochemical properties during high hydrostatic pressure processing (200-400 MPa, 3 min, 25 ℃) and subsequent refrigerated storage were analyzed in this study in order to evaluate the suitability of this non-thermal technology for preservation of fresh-cut Hachiya persimmons. The effects of high-hydrostatic pressure treatment on the integrity and location of carotenoids and tannins during storage were also analyzed. Significant changes, in particular diffusion of soluble compounds which were released as a result of cell wall and membrane damage, were followed using confocal microscopy. The high-hydrostatic pressure process also induced changes in physicochemical properties, e.g. electrolyte leakage, texture, total soluble solids, pH and color, which were a function of the amount of applied hydrostatic pressure and may affect the consumer acceptance of the product. Nevertheless, the results indicate that the application of 200 MPa could be a suitable preservation treatment for Hachiya persimmon. This treatment seems to improve carotenoid extractability and tannin polymerization, which could improve functionality and remove astringency of the fruit, respectively.

Spatial variance of physicochemical properties within mangos and the effect of initial ripeness stage on the quality of fresh-cut mangos.

BACKGROUND: This study aimed to assess the spatial variation in physicochemical properties within individual mangos, as well as to investigate the influence of initial ripeness level on physicochemical characteristics of fresh-cut mangos. Individual mangos were evaluated at 12 specific flesh positions in the inner and outer sides. Mango cubes of 1.5 cm prepared from three firmness stages were monitored for changes during 9 days of storage at 5 °C. RESULTS: Mango fruit varied significantly in firmness and color based on spatial position, with the ripening direction from the inner flesh outward and from the stem end to blossom end. Limitations to fresh-cut mango quality were 'desiccation' (dried cut surface) and 'edge or tissue damage' (cut edge damage or brown and bruise-like appearance). Firmer texture and paler yellow of inner flesh were found in less mature mango fruit (P < 0.001). The optimal ripeness stage for fresh-cut mango products was 45 N, based on ease of handling, fresh appearance at the time of purchase and intermediate physicochemical properties (firmness, color and SSC/TA ratio). CONCLUSION: Spatial variance and initial ripeness stage affect fresh-cut mango quality. Therefore, they must be considered by fresh-cut mango processors in order to attain optimal product quality. © 2015 Society of Chemical Industry.

The effects of bruising and temperature on enzyme activity and textural qualities of tomato juice.

BACKGROUND: During harvest and transportation, processing tomatoes are exposed to elevated temperatures, compression and vibration in the harvester and truck, making them prone to bruising. The objective of this study was to determine how bruising and exposure to high temperatures affect pectin methylesterase (PME) activation and the textural quality of tomato juice. RESULTS: Tomatoes were both hand and mechanically harvested using current harvest practices. Mechanically harvested fruits were significantly softer, had greater PME activity and greater juice consistency than hand harvested fruits. In a controlled bruising study, whole tomatoes were exposed to various compressive forces at 21 or 40 °C and held for 0 or 4 h. Greater bruising force and higher temperature resulted in a decrease in firmness and an increase in PME activity. Consistency of tomato juice improved when tomatoes were exposed to 40 °C. Tomatoes subjected to a temperature range from 21 to 65 °C had activated PME at 40 °C and increased activity as temperature increased. Consistency increased at 35 °C but decreased with increasing temperature. CONCLUSION: Tomatoes harvested using current mechanical techniques are likely to be less firm and have increased PME activity; however, increased consistency of processed juice is observed. Tomatoes harvested at higher temperatures are also likely to have better consistency when processed.

Mineral, fiber, and total phenolic retention in eight fruits and vegetables: a comparison of refrigerated and frozen storage.

Minerals, total phenolics, and fiber were analyzed in several fruit and vegetable commodities to evaluate the differences between fresh and frozen produce. Magnesium, calcium, iron, zinc, and copper were evaluated in corn, carrots, broccoli, spinach, peas, green beans, strawberries, and blueberries. Each commodity was harvested fresh and split into two batches. Half of each commodity was kept fresh, and the other half was frozen. The nutrient content was analyzed over three storage times per treatment. The retention of nutrients was highly dependent on the commodity, but the majority of the commodities showed no significant difference between fresh and frozen for all analytes (p ≤ 0.05).

Vitamin retention in eight fruits and vegetables: a comparison of refrigerated and frozen storage.

Four vitamins were analyzed in several fruit and vegetable commodities to evaluate the differences between fresh and frozen produce. Ascorbic acid, riboflavin, α-tocopherol, and ß-carotene were evaluated in corn, carrots, broccoli, spinach, peas, green beans, strawberries, and blueberries. Samples of each commodity were harvested, processed, and analyzed for nutrient content at three storage times per treatment. Ascorbic acid showed no significant difference for five of the eight commodities and was higher in frozen samples than fresh for the remaining three commodities. Apart from broccoli and peas, which were higher and lower in frozen vs fresh samples, respectively, none of the commodities showed significant differences with respect to riboflavin content. Three commodities had higher levels of α-tocopherol in the frozen samples, while the remaining commodities showed no significant difference between fresh and frozen. ß-Carotene was not found in significant amounts in blueberries, strawberries, and corn. Peas, carrots, and spinach were lower in ß-carotene in the frozen samples, while green beans and spinach showed no significant difference between the two storage methods. Overall, the vitamin content of the frozen commodities was comparable to and occasionally higher than that of their fresh counterparts. ß-Carotene, however, was found to decrease drastically in some commodities.

Effect of acidification on carrot (Daucus carota) juice cloud stability.

Effects of acidity on cloud stability in pasteurized carrot juice were examined over the pH range of 3.5-6.2. Cloud sedimentation, particle diameter, and ζ potential were measured at each pH condition to quantify juice cloud stability and clarification during 3 days of storage. Acidification below pH 4.9 resulted in a less negative ζ potential, an increased particle size, and an unstable cloud, leading to juice clarification. As the acidity increased, clarification occurred more rapidly and to a greater extent. Only a weak effect of ionic strength was observed when sodium salts were added to the juice, but the addition of calcium salts significantly reduced the cloud stability.

Effectiveness of calcium chloride and calcium lactate on maintenance of textural and sensory qualities of fresh-cut mangos.

UNLABELLED: The effects of calcium chloride (CaCl2 ) and calcium lactate on maintaining textural and sensory quality of fresh-cut "Kent" and "Tommy Atkins" mangos and determination of treatments preferred by consumers were investigated. Mango cubes (1.5 × 1.5 × 1.5 cm) were subjected to different CaCl2 and calcium lactate concentrations (0 M, 0.068 M, 0.136 M, 0.204 M) and dip times (0, 1, 2.5, 5 min). Instrumental quality parameters (firmness, color, soluble solids, titratable acidity) were analyzed periodically during 9 d of storage at 5 °C. Tommy Atkins mango cubes became more orange, but also had more browning than Kent mango cubes during storage at 5 °C. Firmness retention during storage was greater with mangos cubes treated with CaCl2 than with calcium lactate, therefore we focused our instrumental analysis only on CaCl2 -treated cubes. The firmness of Tommy Atkins mango cubes was higher than Kent. Soluble solids content (SSC), titratable acidity (TA), and SSC/TA were higher in fresh-cut Kent mango cubes. Mangos treated with CaCl2 showed retarded softening during storage, and the retardation was greater at higher calcium concentrations. A consumer test was conducted to cluster consumers based on mango preference in order to correlate consumer liking and calcium treatments, as well as to uncover consumer intentions for in-store fresh-cut mango purchases. Treatment at 10 °C with 0.136 M CaCl2 for 2.5 min for Tommy Atkins mangos and 1 min for Kent mangos was effective in retaining firmness during storage at 5 °C and was also not disliked by consumers. A cluster analysis divided consumers into 2 preference groups, with Kent mangos significantly preferred over Tommy Atkins. PRACTICAL APPLICATION: Fresh-cut mangos often develop tissue softening and discoloration during storage. Short dips (1 to 3 min) in either CaCl2 or calcium lactate effectively improve fresh-cut mango firmness and color retention after cutting. Mango samples treated with CaCl2 had higher liking scores compared to those treated with calcium lactate. "Kent" mango variety is more suitable than "Tommy Atkins" for fresh-cut processing in terms of less tissue browning and higher consumer liking.

Effects of 1-methylcyclopropene and hot water quarantine treatment on quality of "Keitt" mangos.

The optimal 1-methylcyclopropene (1-MCP) treatment to slow ripening of whole "Keitt" mangos, either alone or in combination with hot water treatment (HWT) (prior to or post 1-MCP) was identified. USDA-APHIS mandates that HWT can be used for control of fruit flies, but this may affect fruit response to 1-MCP. Mangos were evaluated by repeated measurement of nondestructive firmness, peel color, and ethylene production on the same mango fruits during 2 wk of ripening at 20 °C after treatment. The magnitude of ethylene production increased as a result of both 1-MCP and HWT. With softer mangos (65 N), treatment with 1-MCP alone delayed fruit softening and extended the number of days to full-ripeness (25 N) from 5 d in untreated fruit to 11 d. For these riper fruit, application of 1-MCP prior to HWT extended the days to full-ripeness to 9 d compared with 7 d when 1-MCP was applied after HWT. With firmer mangos (80 N), 1-MCP treatments alone prolonged the days to full-ripeness to 13 d as compared to 11 d for the untreated fruit. There was no significant concentration effect on firmness retention among 1-MCP treatments (0.5, 1.0, or 10.0 µL/L). HWT resulted in a faster rate of fruit softening, taking only 7 d to reach full-ripeness. Combining 1-MCP with HWT reduced the rate of softening compared to HWT alone, resulting in 9 to 11 d to full-ripeness. Application of 1-MCP before HWT showed a greater ability to reduce the rate of fruit softening compared with 1-MCP treatment after HWT.

Effect of pectin methylesterase on carrot (Daucus carota) juice cloud stability.

To determine the effect of residual enzyme activity on carrot juice cloud, 0 to 1 U/g pectin methylesterase (PME) was added to pasteurized carrot juice. Cloud stability and particle diameters were measured to quantify juice cloud stability and clarification for 56 days of storage. All levels of PME addition resulted in clarification; higher amounts had a modest effect in causing more rapid clarification, due to a faster increase in particle size. The cloud initially exhibited a trimodal distribution of particle sizes. For enzyme-containing samples, particles in the smallest-sized mode initially aggregated to merge with the second peak over 5-10 days. This larger population then continued to aggregate more slowly over longer times. This observation of a more rapid destabilization process initially, followed by slower subsequent changes in the cloud, was also manifested in measurements of sedimentation extent and in turbidity tests. Optical microscopy showed that aggregation created elongated, fractal particle structures over time.

An integrated approach for flavour quality evaluation in muskmelon (Cucumis melo L. reticulatus group) during ripening.

Numerous and diverse physiological changes occur during fruit ripening and maturity at harvest is one of the key factors influencing the flavour quality of fruits. The effect of ripening on chemical composition, physical parameters and sensory perception of three muskmelon (Cucumis melo L. reticulatus group) cultivars was evaluated. Significant correlations emerging from this extensive data set are discussed in the context of identifying potential targets for melon sensory quality improvement. A portable ultra-fast gas-chromatograph coupled with a surface acoustic wave sensor (UFGC-SAW) was also used to monitor aroma volatile concentrations during fruit ripening and evaluated for its ability to predict the sensory perception of melon flavour. UFGC-SAW analysis allowed the discrimination of melon maturity stage based on six measured peaks, whose abundance was positively correlated to maturity-specific sensory attributes. Our findings suggest that this technology shows promise for future applications in rapid flavour quality evaluation.

Rapid assessment of quality parameters in processing tomatoes using hand-held and benchtop infrared spectrometers and multivariate analysis.

Two portable infrared sensors were evaluated for the rapid determination of quality parameters in processing tomatoes. A total of 370 hot-break juices were prepared from ∼40 processing tomato varieties grown in 5 California counties. The levels of sugars, acids, soluble solids, titratable acidity, and pH in these juices were determined using standard reference methods. Juices were processed, filtered, and directly applied to the FT-IR crystal (15-40 µL) to obtain spectra. Partial least-squares regression (PLSR) was used to generate correlation models, both calibration and validation. The PLS validation models showed good ability (Rval > 0.80; <10% SEP) in estimating the sugars, acids, and especially soluble solids in tomato for both the transmission DialPath portable system and benchtop unit using triple-bounce attenuated total reflectance (ATR). The IR portable unit may provide the tomato processing industry with an efficient method for in-plant, high throughput quantification of quality parameters in tomatoes.