Predição do poder calorífico em Eucalyptus grandis através da espectroscopia de infravermelho próximo (NIR).

EVINCI. Resumo 043

Clinical Predictors of Nondiabetic Kidney Disease in Patients with Diabetes: A Single-Center Study

Background. Although diabetic kidney disease (DKD) could affect up to one-third of patients with diabetes mellitus (DM), these patients can develop kidney diseases different from DKD, or these conditions can superimpose on DKD. Several potential predictors of nondiabetic kidney disease (NDKD) have been proposed, but there are no definitive indications available for kidney biopsy in diabetic patients. Methods. We designed a single-center, cross-sectional, and retrospective cohort study to identify clinical and laboratory factors associated with a diagnosis of NDKD after native kidney biopsy in diabetic patients and to investigate differences in time to end-stage kidney disease (ESKD) in patients with a diagnosis of DKD and NDKD. Results. Of 142 patients included in our analysis, 89 (62.68%) had a histopathological diagnosis of NDKD or mixed NDKD + DKD. Patients in the NDKD group had significantly lower HbA1C, lower prevalence of diabetic retinopathy (DR), and less severe proteinuria, and there was a lower proportion of patients with nephrotic syndrome; the DKD group had significantly lower proportion of patients with hematological conditions. In the multivariate binary logistic regression, only absence of DR and presence of a hematological condition significantly predicted NDKD after adjustment for age and sex. Time to ESKD was significantly higher in patients with NDKD or mixed forms than in those with DKD. Conclusions. After a careful selection, more than half of kidney biopsies performed in diabetic patients can identify NDKD (alone or with concomitant DKD). Absence of DR and coexistence of a hematological condition (especially MGUS) were strong predictors of NDKD in our cohort

Influence of dialysate temperature on creatinine peritoneal clearance in peritoneal dialysis patients: a randomized trial

Background: Patients on continuous ambulatory peritoneal dialysis (PD) are encouraged to warm dialysate to 37 \ub0C before peritoneal infusion; main international PD guidelines do not provide specific recommendation, and patients generally warm dialysate batches partially or do not warm them at all. Warming of dialysate is a time-consuming procedure, not free from potential risks (i.e. degradation of glucose), and should be justified by a clear clinical benefit. Methods: We designed a single blind randomized controlled trial where 18 stable PD patients were randomized to receive a peritoneal equilibration test either with dialysate at a controlled temperature of 37 \ub0C (intervention group) or with dialysate warmed with conventional methods (control group). Primary end-point was a higher peritoneal creatinine clearance in patients in the intervention group. Results: Patients in the intervention group did not show a significantly higher peritoneal creatinine clearance when compared to the control group (6.38 \ub1 0.52 ml/min vs 5.65 \ub1 0.37 ml/min, p = 0.2682). Similar results were obtained for urea peritoneal clearance, mass transfer area coefficient of creatinine and urea. There were no significant differences in total abdominal discomfort questionnaire score, blood pressure and body temperature between the two groups. Conclusions: Using peritoneal dialysate at different temperatures without causing significant side effects to patients appears feasible. We report a lack of benefit of warming peritoneal dialysate to 37 \ub0C on peritoneal clearances; future PD guidelines should not reinforce this recommendation. Trial registration: NCT04302649, ClinicalTrials.gov; date of registration 10/3/2020 (retrospectively registered)

Lanthanide-Induced Photoluminescence in Lead-Free Cs2AgBiBr6Bulk Perovskite: Insights from Optical and Theoretical Investigations

Emphasis was recently placed on the Cs2AgBiBr6 double perovskite as a possible candidate to substitute toxic lead in metal halide perovskites. However, its poor light-emissive features currently make it unsuitable for solid-state lighting. Lanthanide doping is an established strategy to implement luminescence in poorly emissive materials, with the additional advantage of fine-tuning the emission wavelength. We discuss here the impact of Eu and Yb doping on the optical properties of Cs2AgBiBr6 thin films, obtained from the solution processing of hydrothermally synthesized bulk crystalline powders, by combining experiments and density functional theory calculations. Eu(III) incorporation does not lead to the characteristic 5D0 → 7F2 emission feature at 2 eV, while only a weak trap-assisted sub-band gap radiative emission is reported. Oppositely, we demonstrate that incorporated Yb(III) leads to an intense and exclusive photoluminescence emission in the near-infrared as a result of the efficient sensitization of the lanthanide 2F5/2 → 2F7/2 transition

Lanthanide Induced Photoluminescence in Lead-Free Cs₂AgBiBr₆ Bulk Perovskite: Insights From Optical and Theoretical Investigations

The search for materials substituting toxic lead in metal halide perovskites has recently placed emphasis on the Cs2AgBiBr6 double perovskite as a possible candidate. The poor light-emissive features of this species, mainly associated to the indirect nature of the band gap and the strongly bound exciton, however, currently make it unsuitable for solid-state lighting applications. Doping with lanthanides is an established strategy to implement luminescence in poorly emissive materials, with the additional advantage of tuning the wavelength of emission independently from the host band structure. We discuss here the impact of Eu- and Yb-doping on the absorption and emission properties of Cs2AgBiBr6 polycrystalline thin films, obtained from solution-processing of hydrothermally synthesized bulk crystalline powders, by combining experiments and density functional theory calculations. Eu(III) incorporation does not lead to the characteristic 5D0→7F2 emission feature at 2 eV, while only a weak sub band-gap radiative emission ascribed to a trap-assisted recombination process is reported. On the other hand, we demonstrate that Yb(III) incorporated in the bulk double perovskite leads to an intense and exclusive photoluminescence emission in the near-infrared (NIR) from thin films, as a result of the efficient sensitization of the lanthanide centered 2F5/2→2F7/2 transition, with favorable mid-gap energetic position. Yb-doping may be thus exploited for the future development of stable and sustainable perovskite NIR-light emitters

In vitro efficacy and safety of a system for sorbent-assisted peritoneal dialysis

In vitro efficacy and safety of a system for sorbent-assisted peritoneal dialysis. Am J Physiol Renal Physiol 319: F162-F170, 2020. First published June 1, 2020; doi:10.1152/ajprenal. 00079.2020.-A system for sorbent-assisted peritoneal dialysis (SAPD) was designed to continuously recirculate dialysate via a tidal mode using a single lumen peritoneal catheter with regeneration of spent dialysate by means of sorbent technology. We hypothesize that SAPD treatment will maintain a high plasma-to-dialysate concentration gradient and increase the mass transfer area coefficient of solutes. Thereby, the SAPD system may enhance clearance while reducing the number of exchanges. Application is envisaged at night as a bedside device (12 kg, nighttime system). A wearable system (2.0 kg, daytime system) may further enhance clearance during the day. Urea, creatinine, and phosphate removal were studied with the daytime and nighttime system (n = 3 per system) by recirculating 2 liters of spent peritoneal dialysate via a tidal mode (mean flow rate: 50 and 100 mL/min, respectively) for 8 h in vitro. Time-averaged plasma clearance over 24 h was modeled assuming one 2 liter exchange/day, an increase in mass transfer area coefficient, and 0.9 liters ultrafiltration/day. Urea, creatinine, and phosphate removal was 33.2 ± 4.1, 5.3 ± 0.5, and 6.2 ± 1.8 mmol, respectively, with the daytime system and 204 ± 28, 10.3 ± 2.4, and 11.4 ± 2.1 mmol, respectively, with the nighttime system. Time-averaged plasma clearances of urea, creatinine and phosphate were 9.6 ± 1.1, 9.6 ± 1.7, and 7.0 ± 0.9 mL/min, respectively, with the nighttime system and 10.8 ± 1.1, 13.4 ± 1.8, and 9.7 ± 1.6 mL/min, respectively, with the daytime and nighttime system. SAPD treatment may improve removal of uremic toxins compared with conventional peritoneal dialysis, provided that peritoneal mass transport will increase

Prolonged RT-PCR test positivity in hemodialysis patients with COVID-19

Background: The weakened immune system of patients on hemodialysis (HD) may prolong SARS-CoV-2 infection compared to the general population. Current international guidelines recommend ending isolation in conjunction with serial testing in moderately and severely immunocompromised subjects. This study aimed to estimate SARS-CoV-2 infectivity by measuring RT-PCR test positivity in HD patients. A comparison between RT-PCR test and cycle threshold (Ct) value has been performed as a secondary endpoint. Methods: A single-center retrospective study was conducted at the University of Modena (Italy) from March 2020 to October 2022. Only patients on chronic HD therapy with COVID-19 were enrolled in the study. In our HD Center, two negative nasopharyngeal reverse transcription polymerase chain reaction (RT-PCR) results were used to end quarantine in this population. SARS-CoV-2 RT-PCR test positivity duration measured the time elapsed from a positive RT-PCR to a second negative test. Ct cut-off of 35 cycles was used to definite “high Ct value,” a condition characterized by a large number of cycles of PCR amplification to register a positive RT-PCR test. Results: During the observational period, 159 cases of SARS-CoV-2 infections were diagnosed in 151 patients. Median age was 70.1 (54.3–81.6) years and males accounted for 59.6% of the COVID-19 population. Median duration of SARS-CoV-2 RT-PCR test positivity on the nasal mucosa accounted for 30 (IQR, 21–40.5) days. Unvaccinated patients experienced significantly longer RT-PCR test positivity compared to vaccinated patients (42 [IQR,31–56] vs. 28 [IQR,20–35.7] days; p = < 0.001). The use of high Ct value, a laboratory surrogate of SARS-CoV-2 replication, anticipated a negative RT-PCR test of 9 (IQR, 6–12) days. Multivariate linear regression analysis showed that increased age (β coefficient 0.31; confidence interval [CI] 95%, 0.14—0.43; p = < 0.001) and the lack of anti-SARS-CoV-2 vaccination (β 0.49 CI95%, 11.9–22.5; p = < 0.001) were predictors of a prolonged RT-PCR positivity. Conclusions: Patients with COVID-19 on HD had prolonged RT-PCR test positivity. The adoption of “high Ct value” criteria led to a significant reduction in the duration of RT-PCR test positivity compared to the use of the classical nucleic acid amplification test. In our study, the lack of SARS-CoV-2 vaccination and older age were independently associated with a longer RT-PCR positivity