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BACKGROUND: Pulmonary vascular microthrombi are a proposed mechanism of COVID-19 respiratory failure. We hypothesized that early administration of tissue plasminogen activator (tPA) followed by therapeutic heparin would improve pulmonary function in these patients. RESEARCH QUESTION: Does tPA improve pulmonary function in severe COVID-19 respiratory failure, and is it safe? STUDY DESIGN AND METHODS: Adults with COVID-19-induced respiratory failure were randomized from May14, 2020 through March 3, 2021, in two phases. Phase 1 (n = 36) comprised a control group (standard-of-care treatment) vs a tPA bolus (50-mg tPA IV bolus followed by 7 days of heparin; goal activated partial thromboplastin time [aPTT], 60-80 s) group. Phase 2 (n = 14) comprised a control group vs a tPA drip (50-mg tPA IV bolus, followed by tPA drip 2 mg/h plus heparin 500 units/h over 24 h, then heparin to maintain aPTT of 60-80 s for 7 days) group. Patients were excluded from enrollment if they had not undergone a neurologic examination or cross-sectional brain imaging within the previous 4.5 h to rule out stroke and potential for hemorrhagic conversion. The primary outcome was Pao2 to Fio2 ratio improvement from baseline at 48 h after randomization. Secondary outcomes included Pao2 to Fio2 ratio improvement of > 50% or Pao2 to Fio2 ratio of ≥ 200 at 48 h (composite outcome), ventilator-free days (VFD), and mortality. RESULTS: Fifty patients were randomized: 17 in the control group and 19 in the tPA bolus group in phase 1 and eight in the control group and six in the tPA drip group in phase 2. No severe bleeding events occurred. In the tPA bolus group, the Pao2 to Fio2 ratio was significantly (P < .017) higher than baseline at 6 through 168 h after randomization; the control group showed no significant improvements. Among patients receiving a tPA bolus, the Pao2 to Fio2 ratio at 48 h (16.9% [interquartile range (IQR), -8.3% to 36.8%] vs 29.8% [IQR, 4.5%-88.7%]; P = .11), the composite outcome (11.8% vs 47.4%; P = .03), VFD (0.0 [IQR, 0.0-9.0] vs 12.0 [IQR, 0.0-19.0]; P = .11), and in-hospital mortality (41.2% vs 21.1%; P = .19) did not reach statistically significant differences when compared with those of control participants. The patients who received a tPA drip did not experience benefit. INTERPRETATION: The combination of tPA bolus plus heparin is safe in severe COVID-19 respiratory failure. A phase 3 study is warranted given the improvements in oxygenation and promising observations in VFD and mortality. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT04357730; URL: www.clinicaltrials.gov.

The objective of the current study was to evaluate the color changes and lipid oxidation of ground chicken patties packaged in polyvinyl chloride (PVC) film, high-oxygen (HiOx)–modified atmospheric packaging (MAP; 80% oxygen + 20% carbon dioxide [CO2]), and carbon monoxide (CO)-MAP (0.4% CO + 19.6% CO2 + 80% nitrogen) and stored at 2°C. Surface color was measured using a HunterLab MiniScan spectrophotometer on days 0, 1, 2, and 4. Lipid oxidation, pH, and aerobic plate count were determined on days 0 and 4 of storage. Fatty acid profiles were determined on day 0 to characterize saturated and unsaturated fatty acids. Patties packaged in PVC had greater (P < 0.05) pH than HiOx-MAP and CO-MAP. Gas chromatography analysis indicated that ground chicken has 72.8% unsaturated fatty acids and 27.2% saturated fatty acids (based on total lipids and fatty acid methyl ester). The formation of carboxymyoglobin on ground chicken patty surface was confirmed by peaks at 420 and 570 nm, whereas oxymyoglobin had peaks at 410 and 580 nm. Instrumental color analysis indicated both HiOx-MAP and CO-MAP had greater (P < 0.05) redness (a* values) than PVC on day 4 of storage. Patties packaged in HiOx-MAP had greater (P < 0.05) chroma values than CO-MAP and PVC on day 4 of storage. Visual panelists noted less (P < 0.05) surface discoloration in CO-MAP than PVC and HiOx-MAP on day 4 of storage. Lipid oxidation was greater (P < 0.05) in PVC and HiOx-MAP than CO-MAP. CO inclusion at 0.4% level effectively inhibited lipid oxidation and stabilized surface redness during refrigerated storage of ground chicken.

This study was conducted to determine safe cooking times for mechanically tenderized beef steaks prepared from the round, loin, rib, and chuck. The subprimals were needle tenderized and fabricated to prepare a total of 180 steak cuts with varying weights and thicknesses. Steaks were then vacuum packaged and stored at refrigerated temperature until cooked. The dimensions and weight of the steaks were measured pre- and post-cooking. Samples were cooked on a flat-top grill until they reached an internal temperature of 71.1 °C. During cooking, a thermocouple recording device recorded the steak center temperature every 10 s. It was observed that the time required for the steak to reach 71.1 °C significantly influenced by the thickness and type of subprimals of steak. The average cooking yield of steak was 75.66%, while the safe cooking time ranged from 2.22 to 36.66 min. This study could provide valuable information about the effects of weight, thickness and muscle type on the cooking time required for mechanically tenderized beef steaks to reach a minimum safe cooking temperature, without a resting period.

This article provides a comprehensive literature review of the growing significance that foodborne pathogens have on the produce supply and the steps that are taken to reduce them. The numbers of illnesses that are caused by contaminated produce are rising steadily. Three of the most common pathogens that have been seen to cause significant illness in humans through produce are Escherichia coli, Salmonella spp. and Listeria monocytogenes. The antimicrobial interventions, practices and antimicrobials that are currently the most commonly used by the food industry are examined. The literature shows that these antimicrobials currently in use have significant drawbacks when it comes to their role in the produce industry. Sensitivities to temperature and organic load and the production of harmful by products are some of these drawbacks. There is a need for a new antimicrobial that can be used in the produce processing industry. One that maintains its efficacy through the temperature, pH, and organic load changes that are experienced during produce processing. Sodium acid sulfate is a potential contender for this role. It has not previously been used or extensively studied as an antimicrobial, but is already deemed generally recognized as safe (GRAS) product by the Food and Drug Administration (FDA). The use of an antimicrobial that can withstand the varying conditions that the produce industry constantly has is imperative to reducing the number of foodborne illness caused every year by contaminated produce.

This study aims to identify the antimicrobial mode of action of sodium acid sulfate (SAS) and potassium acid sulfate (KAS) against three major foodborne pathogens, Escherichia coli O157:H7, Salmonella Typhimurium DT 104, and Listeria monocytogenes. The overnight grown cultures of the target pathogens were subjected to SAS and KAS treatments to identify the minimum inhibition concentrations of each antimicrobial. The impact of SAS and KAS treatments on the target pathogens at bio-molecular levels was also studied. To help determine if the mode of action is pH-driven, SAS and KAS's antimicrobial efficacies were also compared against hydrochloric acid (HCL). The MIC values of SAS and KAS for all three pathogens were 7.5 mg/mL while for HCL, the MICs were greater than 30 mg/mL. Similarly, SAS and KAS treatments resulted in more damage to all target pathogens and increased leakage of nucleic acid, protein, and ions than HCL treatments. Transmission electron microscope images also revealed that 7.5 mg/mL SAS and KAS treatments resulted in significantly more visible cell damage in S. Typhimurium and E. coli O157:H7 than HCL treatments. The study's findings indicate that the SAS and KAS could be the function of pH, oxidation of cell components, and osmolarity.