Validation of the Kidney Failure Risk Equation in the Colombian Population

Introduction

Chronic kidney disease prevention programs must identify patients at risk of early progression to provide better treatment and prolong kidney replacement therapy-free survival. Risk equations have been developed and validated in cohorts outside of Colombia, so this study aims to evaluate the discrimination and calibration of the four-variable kidney failure risk equation in a Colombian population where it has yet to be validated.

Methods

External validation study of a kidney failure risk equation using a historical cohort of patients with CKD stages 3, 4, and 5, adults without a history of dialysis or kidney transplantation with a two-year follow-up, belonging to the Baxter Renal Care Services Colombia network. The discriminatory capacity of the model was evaluated by the concordance index using Harrell's C statistic, and the time-dependent area under the receiver operating characteristic (ROC) curve was estimated using the nearest neighbor method, as well as the optimal cut-off point for sensitivity and specificity. Calibration was determined by the degree of agreement between the observed outcome and the probabilities predicted by the model using the Hosmer-Lemeshow statistic.

Results

A total of 5,477 patients were included, with a mean age of 72 years, 36.4% diabetic, and a mean baseline eGFR of 36 ml/min/1.73 m2. The rate of dialysis initiation was three events per 100 patient-years, 95% CI (2.9-3.6). The optimal cutoff for sensitivity was 0.94, for specificity, 0.76, and the area under the ROC curve was 0.92. Harrell's C-statistic was 0.88 for the total population, 0.88 for diabetic patients, and 0.93 for those 65 years or older. The validation of the model showed good calibration.

Conclusions

In this Colombian cohort, the four-variable KFRE with a two-year prediction horizon has excellent calibration and discrimination, and its use in the care of CKD Colombian patients is recommended.

KLRG1 expression on natural killer cells is associated with HIV persistence, and its targeting promotes the reduction of the viral reservoir

Human immunodeficiency virus (HIV) infection induces immunological dysfunction, which limits the elimination of HIV-infected cells during treated infection. Identifying and targeting dysfunctional immune cells might help accelerate the purging of the persistent viral reservoir. Here, we show that chronic HIV infection increases natural killer (NK) cell populations expressing the negative immune regulator KLRG1, both in peripheral blood and lymph nodes. Antiretroviral treatment (ART) does not reestablish these functionally impaired NK populations, and the expression of KLRG1 correlates with active HIV transcription. Targeting KLRG1 with specific antibodies significantly restores the capacity of NK cells to kill HIV-infected cells, reactivates latent HIV present in CD4+ T cells co-expressing KLRG1, and reduces the intact HIV genomes in samples from ART-treated individuals. Our data support the potential use of immunotherapy against the KLRG1 receptor to impact the viral reservoir during HIV persistence.

Zinc pyrithione is a potent inhibitor of PLPro and cathepsin L enzymes with ex vivo inhibition of SARS-CoV-2 entry and replication

Zinc pyrithione (1a), together with its analogues 1b–h and ruthenium pyrithione complex 2a, were synthesised and evaluated for the stability in biologically relevant media and anti-SARS-CoV-2 activity. Zinc pyrithione revealed potent in vitro inhibition of cathepsin L (IC₅₀=1.88 ± 0.49 µM) and PL^Pro (IC₅₀=0.50 ± 0.07 µM), enzymes involved in SARS-CoV-2 entry and replication, respectively, as well as antiviral entry and replication properties in an ex vivo system derived from primary human lung tissue. Zinc complexes 1b–h expressed comparable in vitro inhibition. On the contrary, ruthenium complex 2a and the ligand pyrithione a itself expressed poor inhibition in mentioned assays, indicating the importance of the selection of metal core and structure of metal complex for antiviral activity. Safe, effective, and preferably oral at-home therapeutics for COVID-19 are needed and as such zinc pyrithione, which is also commercially available, could be considered as a potential therapeutic agent against SARS-CoV-2.

Evaluation of SARS-CoV-2 entry, inflammation and new therapeutics in human lung tissue cells

The development of physiological models that reproduce SARS-CoV-2 infection in primary human cells will be instrumental to identify host-pathogen interactions and potential therapeutics. Here, using cell suspensions directly from primary human lung tissues (HLT), we have developed a rapid platform for the identification of viral targets and the expression of viral entry factors, as well as for the screening of viral entry inhibitors and anti-inflammatory compounds. The direct use of HLT cells, without long-term cell culture and in vitro differentiation approaches, preserves main immune and structural cell populations, including the most susceptible cell targets for SARS-CoV-2; alveolar type II (AT-II) cells, while maintaining the expression of proteins involved in viral infection, such as ACE2, TMPRSS2, CD147 and AXL. Further, antiviral testing of 39 drug candidates reveals a highly reproducible method, suitable for different SARS-CoV-2 variants, and provides the identification of new compounds missed by conventional systems, such as VeroE6. Using this method, we also show that interferons do not modulate ACE2 expression, and that stimulation of local inflammatory responses can be modulated by different compounds with antiviral activity. Overall, we present a relevant and rapid method for the study of SARS-CoV-2.

Entrectinib-A SARS-CoV-2 Inhibitor in Human Lung Tissue (HLT) Cells

Since the start of the COVID-19 outbreak, pharmaceutical companies and research groups have focused on the development of vaccines and antiviral drugs against SARS-CoV-2. Here, we apply a drug repurposing strategy to identify drug candidates that are able to block the entrance of the virus into human cells. By combining virtual screening with in vitro pseudovirus assays and antiviral assays in Human Lung Tissue (HLT) cells, we identify entrectinib as a potential antiviral drug.

Peripheral and lung resident memory T cell responses against SARS-CoV-2

Resident memory T cells (T_RM) positioned within the respiratory tract are probably required to limit SARS-CoV-2 spread and COVID-19. Importantly, T_RM are mostly non-recirculating, which reduces the window of opportunity to examine these cells in the blood as they move to the lung parenchyma. Here, we identify circulating virus-specific T cell responses during acute infection with functional, migratory and apoptotic patterns modulated by viral proteins and associated with clinical outcome. Disease severity is associated predominantly with IFNγ and IL-4 responses, increased responses against S peptides and apoptosis, whereas non-hospitalized patients have increased IL-12p70 levels, degranulation in response to N peptides and SARS-CoV-2-specific CCR7⁺ T cells secreting IL-10. In convalescent patients, lung-T_RM are frequently detected even 10 months after initial infection, in which contemporaneous blood does not reflect tissue-resident profiles. Our study highlights a balanced anti-inflammatory antiviral response associated with a better outcome and persisting T_RM cells as important for future protection against SARS-CoV-2 infection.

Environmental Disclosure as a Tool for Public Sector Legitimacy

The purpose of this study is to measure the extent of Twitter environmental reporting by Andalusian municipalities (Spain) and identify the determinant factors of such a disclosure. Thus, factors such as population, geolocation, political signs, and sustainable commitments were analyzed under the legitimacy theory approach. The sample consisted of the official Twitter accounts of the 153 biggest local governments in Andalusia. The classification of the environmental tweets was based on a dictionary based on the GRI reporting standards for environmental disclosure, and a Twitter environmental disclosure index (TEDI) was developed. The results show that most of the local governments in Andalusia (77.78%) have an official Twitter account with different levels of audience, penetration, and activity. On the other hand, it was found that environmental disclosure is very low. However, municipalities with more surplus budget and municipalities with a greater number of sustainable commitments networks tend to report more on environmental issues through Twitter.

Na, K, Ca, Mg, and U-series in fossil bone and the proposal of a radial diffusion-adsorption model of uranium uptake

Fossil bones are often the only materials available for chronological reconstruction of important archeological sites. However, since bone is an open system for uranium, it cannot be dated directly and therefore it is necessary to develop models for the U uptake. Hence, a radial diffusion-adsorption (RDA) model is described. Unlike the classic diffusion-adsorption (D-A) model, RDA uses a cylindrical geometry to describe the U uptake in fossil bones. The model was applied across a transverse section of a tibia of an extinct megamammal Macrauchenia patachonica from the La Paz Local Fauna, Montevideo State, Uruguay. Measurements of spatial distribution of Na, K, Ca, and Mg were also performed by neutron activation analysis (NAA). Gamma-ray spectrometric U-series dating was applied to determine the age of the bone sample. From U concentration profile, it was possible to observe the occurrence of a relatively slow and continuous uranium uptake under constant conditions that had not yet reached equilibrium, since the uranium distribution is a ∪-shaped closed-system. Predictions of the RDA model were obtained for a specific geochemical scenario, indicating that the effective diffusion coefficient D/R in this fossil bone is (2.4 ± 0.6)10(-12) cm(2)s(-1). Mean values of Na, K, Ca, and Mg contents along the radial line of the fossil tibia are consistent with the expected behavior for spatial distributions of these mineral elements across a modern bone section. This result indicates that the fossil tibia may have its mineral structure preserved.

Transfer of median and ulnar nerve fascicles for lesions of the posterior cord in infraclavicular brachial plexus injury: report of 2 cases

In infraclavicular lesions of brachial plexus, severe lesions of the posterior cord often occur when medial and lateral cord function is preserved to a greater or lesser extent. In these cases, shoulder function may be preserved by activity of the muscles innervated by the suprascapular nerve, but complete paralysis exists in the deltoid, triceps, and brachioradialis, and all wrist and finger extensors. Classical reconstruction procedures consist of nerve grafts, but their results in adults are disappointing. We report an approach transferring: (1) an ulnar nerve fascicle to the motor branch of the long portion of the triceps brachii muscle, (2) a median nerve branch from the pronator teres to the motor branch of the extensor carpi radialis longus, and (3) a median nerve branch from the flexor carpi radialis to the posterior interosseous nerve. We describe the procedure and report 2 clinical cases showing the effectiveness of this technique for restoring extension of the elbow, wrist, and fingers in the common infraclavicular lesions of the brachial plexus affecting the posterior cord.

Transfer of the nerve to the brachioradialis muscle to the anterior interosseous nerve for treatment for lower brachial plexus lesions: case report

In lower lesions of the brachial plexus (C8-T1) there is good function of the shoulder, elbow, and wrist, although that of the hand is impaired. Reconstruction of finger flexion is generally obtained by tendon transfer. We present a case report involving transfer of the motor nerve branch of the brachioradialis muscle to the anterior interosseous nerve to restore finger flexion in acute lower brachial plexus lesion.

Differential effects of high-fat and high-carbohydrate isoenergetic meals on cardiac autonomic nervous system activity in lean and obese women

Food ingestion can influence autonomic nervous system activity. This study compares the effects of 2 different isoenergetic meals on sympathetic nervous system (SNS) activity, assessed by heart rate variability (HRV) and plasma norepinephrine (NE) levels, in lean and obese women. Fifteen lean and 15 obese healthy women were examined on 2 occasions: after a carbohydrate (CHO)-rich and after a fat-rich test meal. Measurements of blood pressure, heart rate, resting energy expenditure, plasma glucose, lipids, insulin, leptin, and NE, as well as spectral analysis of the HRV, were performed at baseline and every 1 hour for 3 hours after meals. At baseline, obese women had higher SNS activity than lean controls (higher values of low-to-high frequency ratio [LF/HF], 1.52 +/- 0.31 v 0.78 +/- 0.13, P=.04; and plasma NE levels, 405.6 +/- 197.9 v 240.5 +/- 95.8 pg/mL, P<.0001). After the CHO-rich meal a greater increase in LF/HF and in plasma NE levels was observed in lean, compared to obese women (1.21 +/- 0.6 v 0.32 +/- 0.06, P=.04; and 102.9 +/- 35.4 v 38.7 +/- 12.3 pg/mL, P=.01, respectively), while no differences were observed after the fat-rich meal. Meal-induced thermogenesis was higher after the CHO-rich as compared to the fat-rich meal and was comparable between lean and obese women. Changes in HRV were not associated with the thermogenic response to the test meals. In conclusion, consumption of a CHO-rich meal causes greater cardiac SNS activation in lean than in obese women, while fat ingestion does not result in any appreciable change in either group. SNS activation does not appear to influence the thermic effect of the food in either lean or obese women.

Lack of Effect of Acute Repaglinide Administration on Postprandial Lipaemia in Patients with Type 2 Diabetes Mellitus

The effect of acute repaglinide administration (2 mg) on postprandial glycaemia and lipaemia has been examined in 20 subjects with type 2 diabetes mellitus. Each subject received in the morning, after a 12 to 14 h fast, a standard mixed meal (total energy 783 kcal), preceded by one tablet of 2 mg repaglinide or placebo. Chylomicrons and chylomicron-deficient plasma were prepared by ultracentrifugation. Triglyceride levels in CM fraction (CM-triglycerides) in total plasma as well as in CM-deficient plasma (non-CM-triglycerides) were determined. A significant reduction in postprandial glycaemia was observed after repaglinide administration compared to placebo ( p < 0.001). Plasma concentrations of total triglycerides, CM-triglycerides, non-CM-triglycerides, free fatty acids and the other plasma lipids measured, were not significantly different between the two phases of the study. It is concluded that, in contrast to sulphonylureas, acute repaglinide administration does not improve postprandial lipaemia in patients with type 2 diabetes.