Effectiveness of COVID-19 vaccines in a large European hemodialysis cohort.

Background: Hemodialysis patients have high-risk of severe SARS-CoV-2 infection but were unrepresented in randomized controlled trials evaluating the safety and efficacy of COVID-19 vaccines. We estimated the real-world effectiveness of COVID-19 vaccines in a large international cohort of hemodialysis patients. Methods: In this historical, 1:1 matched cohort study, we included adult hemodialysis patients receiving treatment from December 1, 2020, to May 31, 2021. For each vaccinated patient, an unvaccinated control was selected among patients registered in the same country and attending a dialysis session around the first vaccination date. Matching was based on demographics, clinical characteristics, past COVID-19 infections and a risk score representing the local background risk of infection at vaccination dates. We estimated the effectiveness of mRNA and viral-carrier COVID-19 vaccines in preventing infection and mortality rates from a time-dependent Cox regression stratified by country. Results: In the effectiveness analysis concerning mRNA vaccines, we observed 850 SARS-CoV-2 infections and 201 COVID-19 related deaths among the 28110 patients during a mean follow up of 44 ± 40 days. In the effectiveness analysis concerning viral-carrier vaccines, we observed 297 SARS-CoV-2 infections and 64 COVID-19 related deaths among 12888 patients during a mean follow up of 48 ± 32 days. We observed 18.5/100-patient-year and 8.5/100-patient-year fewer infections and 5.4/100-patient-year and 5.2/100-patient-year fewer COVID-19 related deaths among patients vaccinated with mRNA and viral-carrier vaccines respectively, compared to matched unvaccinated controls. Estimated vaccine effectiveness at days 15, 30, 60 and 90 after the first dose of a mRNA vaccine was: for infection, 41.3%, 54.5%, 72.6% and 83.5% and, for death, 33.1%, 55.4%, 80.1% and 91.2%. Estimated vaccine effectiveness after the first dose of a viral-carrier vaccine was: for infection, 38.3% without increasing over time and, for death, 56.6%, 75.3%, 92.0% and 97.4%. Conclusion: In this large, real-world cohort of hemodialyzed patients, mRNA and viral-carrier COVID-19 vaccines were associated with reduced COVID-19 related mortality. Additionally, we observed a strong reduction of SARS-CoV-2 infection in hemodialysis patients receiving mRNA vaccines.

The effects of time and relative humidity on dry-aged beef: Traditional versus special bag.

The objective of this study was to evaluate the effects of relative humidity (RH) and different dry aging methods on the quality of beef. Sixteen loins, from eight carcasses, were used in this experiment. Each pair of loin was cut into eight sections with equal size, which were evenly assigned to eight treatments, by the combination of two dry aging methods (traditional and highly moisture-permeable special bag), two relative humidity (65 and 85% RH) and two aging times (21 and 42 days). At 85% RH, neither special bag nor the traditional dry aging methods were viable, since samples presented high microbiological counts, mucus and bad odor. At 65% RH, Enterobacteriaceae and lactic acid bacteria were not detected in any treatment. The highest aerobic plate count and psychrotrophic count were observed in the samples of the traditional dry-aged process whereas the special bag showed the greatest mold and yeast count. Regarding dry aging in special bag, there was a reduction in the weight loss (P < 0.05) and no change in the physical-chemical characteristics (P > 0.05) compared to traditional dry aging. The values of pH, moisture and Warner-Bratzler shear force were not affected (P > 0.05) by aging method and relative humidity. Thus, the results indicate that high RH should be avoided for both dry aging methods. Furthermore, the special bag dry aging can be considered an alternative to produce dry-aged beef, as it reduces weight losses even at conditions of lower relative humidity.

The Effects of Melatonin Supplementation on Sleep Quality and Assessment of the Serum Melatonin in ICU Patients: A Randomized Controlled Trial.

OBJECTIVES: To evaluate whether the use of exogenous melatonin affects sleep, reduces the prevalence of delirium, and decreases the need for analgosedation and to assess whether serum melatonin indices correlate with exogenous administration in critically ill patients. DESIGN: Double-blind, randomized, placebo-controlled study. SETTING: Multicenter ICUs of two tertiary hospitals. PATIENTS: A total of 203 adult patients who were admitted to the ICU and administered with analgesics and/or sedatives. INTERVENTIONS: Oral melatonin (10 mg) or placebo for up to seven consecutive nights. MEASUREMENTS AND MAIN RESULTS: The number of observed sleeping hours at night was assessed by the bedside nurse. Sleep quality was evaluated using the Richards Campbell Questionnaire Sleep (RCSQ). The prevalence of delirium, pain, anxiety, adverse reactions, duration of mechanical ventilation, length of ICU and hospital stays, and doses of sedative and analgesic drugs administered were recorded. The use of analgesics and sedatives was assessed daily. Melatonin levels were determined by enzyme-linked immunosorbent assay. Based on the RCSQ results, sleep quality was assessed to be better in the melatonin group than that in the placebo group with a mean (SD) of 69.7 (21.2) and 60.7 (26.3), respectively (p = 0.029). About 45.8% and 34.4% of participants in the melatonin and placebo groups had very good sleep (risk ratio, 1.33; 95% CI, 0.94-1.89), whereas 3.1% and 14.6% had very poor sleep (risk ratio, 0.21; 95% CI, 0.06-0.71), respectively. No significant difference was observed regarding the days free of analgesics or sedatives, the duration of night sleep, and the occurrence of delirium, pain, and anxiety. Melatonin serum peak levels at 2 AM were 150 pg/mL (range, 125-2,125 pg/mL) in the melatonin group and 32.5 pg/mL (range, 18.5-35 pg/mL) in the placebo group (p < 0.001). CONCLUSIONS: Melatonin was associated with better sleep quality, which suggests its possible role in the routine care of critically ill patients in the future.

Effects of freezing and thawing on microbiological and physical-chemical properties of dry-aged beef.

This study evaluated the effects of freezing, prior to and after dry aging, on the microbiological and physical-chemical quality of beef. Strip loins (n = 24) from 12 carcasses were assigned to four treatments: non-frozen dry aging (Dry); dry aging, steak fabrication, freezing and slow thawing (Dry + ST); freezing, fast thawing (FT; 20 °C/15 h) and dry aging (FT + Dry); freezing, slow thawing (ST; 4 °C/48 h) and dry aging (ST + Dry). Freezing conditions were - 20 °C/28 days and dry aging conditions were 2 °C/70% relative humidity, for 28 days. Freezing prior to dry aging did not affect the microbial counts compared to Dry. However, FT + Dry and ST + Dry increased (16%) total process loss (P < .05) compared to Dry and Dry+ST. Moreover, freezing changed volatile compounds profile. Thus, freezing prior to dry aging was not a feasible process due to increased process loss, while freezing after dry aging was considered a viable alternative to preserve the steaks without compromising beef physical-chemical traits.

Maturação seca e úmida da carne bovina e seus efeitos na qualidade sensorial e microbiológica

O perfil do consumidor brasileiro se tomou mais exigente em relação à qualidade da carne. Entre os atributos que fazem parte dessa definição, as características de palatabilidade são de suma importância para a avaliação de consumidor e podem ser melhoradas por meio da maturação. Essa técnica consiste em armazenar a carne em câmaras frias, sob condições controladas de temperatura, umidade relativa e velocidade do ar, por um período de tempo, a fim de que enzimas endógenas promovam mudanças em sua estrutura. Os métodos de maturação seca e úmida podem interferir diferentemente em muitos atributos. Em razão disso, esta revisão bibliográfica objetivou comparar esses dois processos, frente a alguns dos parâmetros de palatabilidade, como maciez, sabor e aroma da carne bovina, além da qualidade microbiológica dos produtos. Conclui-se que os processos de maturação, úmido e seco, melhoram a maciez da carne na mesma proporção, mas a maturação a seco possibilita o desenvolvimento de atributos de sabor mais desejáveis, quando comparado com a maturação úmida. Entretanto, os mecanismos responsáveis por esta melhoria ainda não são claros e precisam ser melhor investigados. De maneira geral a proliferação de micro-organismos é melhor controlada na maturação a seco, mas cuidados especiais devem ser tomados quando da etapa de toalete, remoção das superfícies ressecadas, para não haver contaminação cruzada.

The Brazilian consumer's profile has become more rigorous regarding to meat quality. Among the attributes that are part of definition of quality, palatability characteristics are the main concern for consumer evaluation and may be improved by aging. This technique consists in storing the meat in cold storage under controlled conditions of temperature, relative humidity and air flow during a period of time in order to promote changes in its structure by the activity of endogenous enzymes. The dry-aging and wet-aging differ in many attributes. Therefore, this review proposes to compare those two processes regarding to some of their palatability parameters such as tenderness, flavor and aroma in beef, in addition to verify the microbiological quality of the products. lt is concluded that the dry aging process is simple, but requires special care to meet desired sensory results and ensure microbiological safety.

Maturação seca e úmida da carne bovina e seus efeitos na qualidade sensorial e microbiológica

O perfil do consumidor brasileiro se tornou mais exigente em relação à qualidade da carne. Entre os atributos que fazem parte dessa definição, as características de palatabilidade são de suma importância para a avaliação do consumidor e podem ser melhoradas por meio da maturação. Essa técnica consiste em armazenar a carne em câmaras frias, sob condições controladas de temperatura, umidade relativa e velocidade do ar, por um período de tempo, a fim de que enzimas endógenas promovam mudanças em sua estrutura. Os métodos de maturação seca e úmida podem interferir diferentemente em muitos atributos. Em razão disso, esta revisão bibliográfica objetivou comparar esses dois processos, frente a alguns dos parâmetros de palatabilidade, como maciez, sabor e aroma da carne bovina, além da qualidade microbiológica dos produtos. Conclui-se que os processos de maturação, úmido e seco, melhoram a maciez da carne na mesma proporção, mas a maturação a seco possibilita o desenvolvimento de atributos de sabor mais desejáveis, quando comparado com a maturação úmida. Entretanto, os mecanismos responsáveis por esta melhoria ainda não são claros e precisam ser melhor investigados. De maneira geral a proliferação de micro-organismos é melhor controlada na maturação a seco, mas cuidados especiais devem ser tomados quando da etapa de toalete, remoção das superfícies ressecadas, para não haver contaminação cruzada

The Brazilian consumer's profile has become more rigorous regarding to meat quality. Among the attributes that are part of definition of quality, palatability characteristics are the main concern for consumer evaluation and may be improved by aging. This technique consists in storing the meat in cold storage under controlled conditions of temperature, relative humidity and air flow during a period of time in order to promote changes in its structure by the activity of endogenous enzymes. The dry-aging and wet-aging differ in many attributes. Therefore, this review proposes to compare those two processes regarding to some of their palatability parameters such as tenderness, flavor and aroma in beef, in addition to verify the microbiological quality of the products. It is concluded that the dry aging process is simple, but requires special care to meet desired sensory results and ensure microbiological safety

Insulin Resistance in Nondiabetic Peritoneal Dialysis Patients: Associations with Body Composition, Peritoneal Transport, and Peritoneal Glucose Absorption.

BACKGROUND AND OBJECTIVES: Insulin resistance has been associated with cardiovascular disease in peritoneal dialysis patients. Few studies have addressed the impact of fast transport status or dialysis prescription on insulin resistance. The aim of this study was to test whether insulin resistance is associated with obesity parameters, peritoneal transport rate, and glucose absorption. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Insulin resistance was evaluated with homeostasis model assessment method (HOMA-IR), additionally corrected by adiponectin (HOMA-AD). Enrolled patients were prevalent nondiabetics attending at Santo António Hospital Peritoneal Dialysis Unit, who were free of hospitalization or infectious events in the previous 3 months (51 patients aged 50.4 ± 15.9 years, 59% women). Leptin, adiponectin, insulin-like growth factor-binding protein 1 (IGFBP-1), and daily glucose absorption were also measured. Lean tissue index, fat tissue index (FTI), and relative fat mass (rel.FM) were assessed using multifrequency bioimpedance. Patients were categorized according to dialysate to plasma creatinine ratio at 4 hours, 3.86% peritoneal equilibration test, and obesity parameters. RESULTS: Obesity was present in 49% of patients according to rel.FM. HOMA-IR correlated better with FTI than with body mass index. Significant correlations were found in obese, but not in nonobese patients, between HOMA-IR and leptin, leptin/adiponectin ratio (LAR), and IGFBP-1. HOMA-IR correlated with HOMA-AD, but did not correlate with glucose absorption or transport rate. There were no significant differences in insulin resistance indices, glucose absorption, and body composition parameters between fast and nonfast transporters. A total of 18 patients (35.3%) who had insulin resistance presented with higher LAR and rel.FM (7.3 [12.3, interquartile range] versus 0.7 [1.4, interquartile range], P<0.001, and 39.4 ± 10.1% versus 27.2 ± 11.5%, P=0.002, respectively), lower IGFBP-1 (8.2 ± 7.2 versus 21.0 ± 16.3 ng/ml, P=0.002), but similar glucose absorption and small-solute transport compared with patients without insulin resistance. FTI and LAR were independent correlates of HOMA-IR in multivariate analysis adjusted for glucose absorption and small-solute transport (r=0.82, P<0.001). CONCLUSIONS: Insulin resistance in nondiabetic peritoneal dialysis patients is associated with obesity and LAR independent of glucose absorption and small-solute transport status. Fast transport status was not associated with higher likelihood of obesity or insulin resistance.

Adipokines in peritoneal dialysis: relevant clinical impact according to body composition.

Adipokines impact on clinical outcomes is not adequately addressed in peritoneal dialysis (PD). We investigated the impact of leptin/adiponectin ratio (L/A) as a predictor of cardiovascular events (CVE) in PD, taking into consideration patient's body composition and the potential role of glucose load. We prospectively followed 66 prevalent PD patients for 47.0 ± 28.2 months. New CVE were evaluated. Lean tissue index (LTI), relative fat mass (relFM) and relative overhydration (relOH) using multifrequency bioimpedance (BCM) were assessed; serum lipids, interleukin-6 (IL-6), leptin and adiponectin were measured. We established the determinants of L/A using multiple linear regression and the impact of L/A on CVE. Obesity was present in 47 (73.4%) patients according to relFM, and in seven (10.6%) according to body mass index (BMI). Leptin and L/A exhibited a stronger correlation with relFM (both r = 0.62, P < 0.0001) than with BMI (r = 0.46 and r = 0.51, respectively, both P < 0.0001). L/A showed a significant correlation with triglycerides (r = 0.41, P = 0.001) and HDL-cholesterol (r = -0.358, P = 0.003), better than isolated leptin or adiponectin. RelFM (RR = 0.130, 95%confidence interval [CI]:0.086-0.174, P < 0.0001) and LTI (RR = 0.194, 95%CI:0.037-0.351, P = 0.016) were independent predictors of L/A (R(2) = 0.67). Patients who suffered new CVE were older (59.12 ± 12.41 vs. 47.52 ± 13.84years, P = 0.003) and had a higher relOH (11.28 ± 7.29 vs. 6.60 ± 8.16%, P = 0.028). L/A was significantly higher in patients with CVE[2.29 (1.79) vs. 0.65 (1.73), P = 0.028] but this association was only put on evidence after excluding patients with wasting. BMI is an inaccurate method to classify obesity in PD since it underestimates its prevalence compared with body composition assessment using BCM. High adiponectin and low leptin are associated with a more favorable metabolic risk profile in peritoneal dialysis. The L/A is determined by relFM and by LTI. A higher L/A is associated with CVE in PD patients without wasting.

Hepatocyte growth factor signalizes peritoneal membrane failure in peritoneal dialysis.

BACKGROUND: Hepatocyte growth factor (HGF) counteracts peritoneal fibrosis in animal models and in-vitro studies, but no study explored effluent HGF in peritoneal dialysis (PD) patients with ultrafiltration failure (UFF). Our aim was to assess the relationship between effluent HGF with UF profile, free water transport (FWT) and small-solute transport. METHODS: We performed 4-hour, 3.86% PET with additional UF measurement at 60 minutes in 68 PD patients. MTACcreatinine, FWT, small-pore ultrafiltration, and effluent HGF were quantified. RESULTS: Effluent HGF negatively correlated with UF (r=-0.80, p=0.009) and FWT (r=-0.69, p=0.04). Patients with UFF had higher dialysate HGF (103 pg/mL vs 77 pg/mL, p=0.018) and, although not statistically significant, those with FWT compromise had also higher dialysate HGF compared with subgroup of UFF without FWT compromise (104 pg/mL vs 88 pg/mL, p=0.08). FWT≤45% without clinical UFF was documented in some patients who also had increased effluent HGF. CONCLUSIONS: Dialysate HGF concentration is significantly higher among patients with UFF, specially, if FWT is impaired, being a sign of peritoneal membrane deterioration.

Two-in-one protocol: simultaneous small-pore and ultrasmall-pore peritoneal transport quantification.

BACKGROUND: Reduced free water transport (FWT) through ultrasmall pores contributes to net ultrafiltration failure (UFF) and should be seen as a sign of more severe functional deterioration of the peritoneal membrane. The modified peritoneal equilibration test (PET), measuring the dip in dialysate Na concentration, estimates only FWT. Our aim was to simultaneously quantify small-solute transport, FWT, and small-pore ultrafiltration (SPUF) during a single PET procedure. METHODS: We performed a 4-hour, 3.86% glucose PET, with additional measurement of ultrafiltration (UF) at 60 minutes, in 70 peritoneal dialysis patients (mean age: 50 ± 16 years; 61% women; PD vintage: 26 ± 23 months). We calculated the dialysate-to-plasma ratios (D/P) of creatinine and Na at 0 and 60 minutes, and the Na dip (Dip(D/PNa60')), the delta dialysate Na 0-60 (ΔDNa(0-60)), FWT, and SPUF. RESULTS: Sodium sieving (as measured by ΔDNa(0-60)) correlated strongly with the corrected Dip(D/PNa60') (r = 0.85, p < 0.0001) and the corrected FWT (r = 0.41, p = 0.005). Total UF showed better correlation with FWT than with indirect measurements of Na sieving (r = 0.46, p < 0.0001 for FWT; r = 0.360, p < 0.0001 for Dip(D/PNa60')). Corrected FWT fraction was 0.45 ± 0.16. A negative correlation was found between time on PD and both total UF and FWT (r = -0.253, p = 0.035 and r = -0.272, p = 0.023 respectively). The 11 patients (15.7%) diagnosed with UFF had lower FWT (89 mL vs 164 mL, p < 0.05) and higher D/P creatinine (0.75 vs 0.70, p < 0.05) than did the group with normal UF. The SPUF correlated positively with FWT in the normal UF group, but negatively in UFF patients (r = -0.709, p = 0.015). Among UFF patients on PD for a longer period, 44.4% had a FWT percentage below 45%. CONCLUSIONS: Measurement of FWT and SPUF is feasible by simultaneous quantification during a modified 3.86% glucose PET, and FWT is a decisive parameter for detecting causes of UFF in addition to increased effective capillary surface.

Peritoneal membrane phosphate transport status: a cornerstone in phosphate handling in peritoneal dialysis.

BACKGROUND AND OBJECTIVES: Phosphate control impacts dialysis outcomes. Our aim was to define peritoneal phosphate transport in peritoneal dialysis (PD) and to explore its association with hyperphosphatemia, phosphate clearance (PPhCl), and PD modality. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Two hundred sixty-four patients (61% on continuous ambulatory PD [CAPD]) were evaluated at month 12. PPhCl was calculated from 24-hour peritoneal effluent. Phosphate (Ph) and creatinine (Cr) dialysate/plasma (D/P) were calculated at a 4-hour 3.86% peritoneal equilibration test. RESULTS: D/PPh correlated with D/PCr. PPhCl correlated better with D/PPh than with D/PCr. Prevalence of hyperphosphatemia (>5.5 mg/dl) was 30%. In a multiple regression analysis, only residual renal function was independently, negatively associated with hyperphosphatemia; in anuric patients, only D/PPh was an independent factor predicting hyperphosphatemia. D/PPh was 0.57 ± 0.10, and according to this, 16% of the patients were fast, 31% were fast-average, 35% were slow-average, and 17% were slow transporters. PPhCl was 37.5 ± 11.7 L/wk; it was lower in the slow transporter group (31 ± 14 L/wk). Among fast and fast-average transporters, PPhCl was comparable in both PD modalities. In comparison to automated PD, CAPD was associated with increased PPhCl among slow-average (36 ± 8 versus 32 ± 7 L/wk) and slow transporters (34 ± 15 versus 24 ± 9 L/wk). CONCLUSIONS: In hyperphosphatemic, particularly anuric, patients, optimal PD modality should consider peritoneal phosphate transport characteristics. Increasing dwell times and transfer to CAPD are effective strategies to improve phosphate handling in patients with inadequate phosphate control on automated PD.