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This paper presents an application for a molybdenum disulfide nanomaterial with multiwalled carbon nanotubes (MoS2@MWCNT/E) in a modified electrode substrate for the detection of uric acid (UA). The modified electrode generates a substantial three-fold increase in the anodic peak current for UA compared to the unmodified MWCNT electrode (MWCNT/E). The MoS2@MWCNT/E surface was characterized by cyclic voltammetry (CV), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS) and electrochemical impedance spectroscopy (EIS). The achieved detection limit stood at 0.04 µmol/L, with a relative standard deviation (RSD) of 2.0% (n = 10). The method's accuracy, assessed through relative error and percent recovery, was validated using a urine standard solution spiked with known quantities of UA.

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In hominids, including Homo sapiens, uric acid is the end product of purine catabolism. In contrast, other placental mammals further degrade uric acid to (S)-allantoin by enzymes such as urate oxidase (uricase), HIU hydrolase (HIUase), and OHCU decarboxylase. Some organisms, such as frogs and fish, hydrolyze (S)-allantoin to allantoate and eventually to (S)-ureidoglycolate and urea, while marine invertebrates convert urea to ammonium. In H. sapiens, mutations in the uricase gene led to a reduction in the selective pressure for maintaining the integrity of the genes encoding the other enzymes of the purine catabolism pathway, resulting in an accumulation of uric acid. The hyperuricemia resulting from this accumulation is associated with gout, cardiovascular disease, diabetes, and preeclampsia. Many commonly used drugs, such as aspirin, can also increase uric acid levels. Despite the apparent absence of these enzymes in H. sapiens, there appears to be production of transcripts for uricase (UOX), HIUase (URAHP), OHCU decarboxylase (URAD), and allantoicase (ALLC). While some URAHP transcripts are classified as long non-coding RNAs (lncRNAs), URAD and ALLC produce protein-coding transcripts. Given the presence of these transcripts in various tissues, we hypothesized that they may play a role in the regulation of purine catabolism and the pathogenesis of diseases associated with hyperuricemia. Here, we specifically investigate the unique aspects of purine catabolism in H. sapiens, the effects mutations of the uricase gene, and the potential regulatory role of the corresponding transcripts. These findings open new avenues for research and therapeutic approaches for the treatment of hyperuricemia and related diseases.

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INTRODUCTION: Although some studies have reported the association between uric acid (UA) and hypertension, evidence on prehypertension is still lacking. Therefore, the objective of this study was to determine the levels of UA and other cardiovascular markers among prehypertensive and hypertensive patients and assess their risk for developing arterial hypertension. METHODS: 157 individuals were recruited: 67 normotensive, 23 pre-hypertensive and 67 hypertensive. Blood samples were collected to measure biochemical parameters and anthropometric measurements and blood pressure were evaluated. We calculated the product of lipid accumulation and the visceral adiposity index to assess cardiovascular risk. RESULTS: Our data showed an increase in UA levels in normotensives (4.9±1.3mg/dL), prehypertensives (5.2±1.3mg/dL) and hypertensives (5.9±1.6mg/dL) (p=0.004). We found a higher frequency of hyperuricemia in the hypertensive group (34.3%) than in the normotensive group (13.4%, p<0.05). Hypertensive volunteers had lower levels of HDL-C (p=0.004 and p=0.003) and higher body mass indexes (p<0.001 and p=0.007), glucose (p<0.001 and p=0.033), triglycerides (p=0.001 and p=0.005), visceral adiposity index (p<0.001 and p=0.002) and lipid accumulation product (p<0.001 and p=0.007) than normotensive and prehypertensive participants. We also observed that individuals with UA≥6.2mg/dL had an increased risk of hypertension of 4.77 (p=0.003) compared to individuals with levels≤4.3mg/dL. CONCLUSION: Our results showed that UA is associated with increased blood pressure and unfavorable changes in anthropometric and biochemical parameters, which represent risk factors for hypertension and cardiovascular diseases.

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The development of inexpensive and portable point-of-care devices for measuring nutritional physiological parameters from blood (e.g., glucose, ketones) has accelerated our understanding and assessment of real-time variation in human health, but these have infrequently been tested or implemented in wild animals, especially in relation to other key biological or fitness-related traits. Here we used point-of-care devices to measure blood levels of glucose, ketones, uric acid, and triglycerides in free-ranging house finches (Haemorhous mexicanus)-a common songbird in North America that has been well-studied in the context of urbanization, nutrition, health, and sexual selection-during winter and examined (1) repeatability of these methods for evaluating blood levels in these wild passerines, (2) intercorrelations among these measurements within individuals, (3) how blood nutritional-physiology metrics related to a bird's body condition, habitat of origin (urban vs. suburban), poxvirus infection, and sex; and (4) if the expression of male sexually selected plumage coloration was linked to any of the nutritional-physiological metrics. All blood-nutritional parameters were repeatable. Also, there was significant positive covariation between concentrations of circulating triglycerides and glucose and triglycerides and uric acid. Urban finches had higher blood glucose concentrations than suburban finches, and pox-infected individuals had lower blood triglyceride concentrations than uninfected ones. Last, redder males had higher blood glucose, but lower uric acid levels. These results demonstrate that point-of-care devices can be useful, inexpensive ways of measuring real-time variation in the nutritional physiology of wild birds.

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BACKGROUND: The relationship between serum concentration of uric acid (UA) and chronic kidney disease is complex due to many confounding variables. There is currently debate over whether hyperuricemia acts as a marker of kidney disease or as an independent risk factor. OBJECTIVES: To test the impact of serum UA concentration on the estimated glomerular filtration rate (GFR) of children undergoing kidney transplantation. PATIENTS AND METHODS: Prospective longitudinal study of children and adolescents after kidney transplantation. We analyzed clinical, anthropometric, and laboratory data at pre-transplant and 1, 3, and 6 months after transplant. We developed models of repeated measures analysis, using the generalized estimating equations technique for the outcome evolution of the estimated GFR at 1, 3 and 6 months. High serum UA concentration at 1 and 3 months was modeled as the main exposure variable. RESULTS: We included 103 transplant patients. In a model adjusted for time, recipient sex and age, the occurrence of acute rejection episodes, and the estimated glomerular filtration at baseline, the trajectory of GFR exhibited an inverse relationship with UA (ß = -7.1, 95% CI: -11.5 to -2.6, p < .01). CONCLUSION: Serum UA increase was associated with lower graft function over time.

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INTRODUCTION: Robust evidence exists regarding initiation, intensification or modification of treatments. Recommendations to de-escalate therapy are lacking, specifically in diabetes. A successful treatment de-intensification reduces overtreatment, polypharmacy, and risk of adverse effects. OBJECTIVE: To encompass current recommendations for deprescribing common drugs and create a consensus among health professionals. METHODS: We reviewed four databases for deprescribing approaches published between 2010 and 2022. Articles were divided into different groups of drugs (for uric-acid, hypoglycemic, lipid-lowering, and psychotropic drugs). RESULTS: Hypoglycemic agents: strategies were limited to newer agents and insulin regimens for elderly individuals. Reducing insulin was associated with 1.1% reduction of A1c over time. SGLT2i and GLP-1RAs dose reduction depends on adverse events. Lipid-lowering agents: studies show that patients with very low cholesterol have fewer cardiovascular events without associated increased risk. Antihypertensive agents: Younger patients, lower systolic blood pressure, and few comorbidities are ideal characteristics for discontinuation. Uric acid therapy: we found no recommendation for dose de-escalation. Poor treatment adherence is associated with episodes of gout and deforming arthritis in the long term. CONCLUSION: Deprescribing hypoglycemic, statins, antihypertensives, and urate-lowering agents may be feasible in selected patients, but periodic surveillance is important. More evidence is necessary to support this decision entirely.

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PURPOSE: Uric acid (UA) plays a dual role as an antioxidant and a prooxidant in patients with malignant tumors; however, the relationship between serum UA and malignancy is currently unclear. This study aims to investigate the prognostic value of serum uric acid level before immunotherapy on the efficacy of primary liver cancer (PLC) immunotherapy, which might provide a basis for optimizing the comprehensive treatment scheme. METHODS: Patients with PLC who were admitted to the First Affiliated Hospital of Gannan Medical College from January 2019 to June 2022 and underwent immunotherapy were collected retrospectively. The difference between serum UA levels in patients with PLC, the correlation between serum UA levels, and the clinical characteristics of patients with PLC were analyzed using the chi-square test, and the survival was estimated using the Kaplan-Meier analysis. To further assess the prognostic significance of UA concentrations, univariate and multivariate Cox regression analyses were performed. RESULTS: Ninety-nine patients were included in this study cohort. The median follow-up was 7 months (range: 1-29 months), and 76 (76.8%) of the 99 patients with PLC died as of December 31, 2022. Serum UA concentrations ranged from 105 to 670 µmol/l, with a median of 269 µmol/l. The results showed that the serum UA level of patients with PLC was higher than that of healthy subjects (P < 0.001). After subgroup analyses, only male patients with liver cancer had higher serum UA levels than healthy men (P = 0.001). The results of the Kaplan-Meier analysis showed that higher UA levels were associated with poor overall survival (OS) (P = 0.005). In univariate analysis, the OS rate of patients with elevated serum UA levels was significantly lower than the cut-off value (hazard ratio [HR]: 3.191, 95% confidence interval [CI]: 1.456-6.993, P = 0.004), with a median survival time of 151 and 312 days in the high and low serum UA groups, respectively. The results of multivariate analysis showed that the UA level was an independent prognostic factor for immunotherapy in patients with PLC (HR: 3.131, 95% CI: 1.766-5.553, P < 0.001). CONCLUSIONS: The serum UA level is a reliable biomarker for predicting the prognosis of patients undergoing immunotherapy for PLC, and might provide a basis for the individualized treatment of these patients. Dynamic monitoring of the serum UA level may compensate for the deficiency of the current liver cancer staging system.

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OBJECTIVE: Serum uric acid is proven to be associated with chronic hearing loss, but its effect on Sudden Sensorineural Hearing Loss (SSNHL) is unclear. This study aims to evaluate the prognostic values of serum uric acid levels in SSNHL patients. METHODS: The clinical records of SSNHL patients were retrospectively reviewed. Patients were divided into different groups based on hearing recovery and audiogram type, and uric acid levels were compared. Based on uric acid levels, patients were categorized into normouricemia and hyperuricemia groups, and clinical features and hearing recovery were evaluated. Univariate and multivariate analyses were performed to identify prognostic factors. RESULTS: In total, 520 SSNHL patients were included in this study, including 226 females and 294 males. In female patients, 186 patients were included in the normouricemia group, and 40 patients were enrolled in the hyperuricemia group. Significant differences were observed in uric acid levels, Total Cholesterol (TC), rate of complete recovery, and slight recovery between the two groups. In male patients, 237 subjects were categorized into the normouricemia group, and 57 patients were included in the hyperuricemia group. The rate of complete recovery and slight recovery was lower in the hyperuricemia group compared to the normouricemia group. All patients were further divided into good recovery and poor recovery groups based on hearing outcomes. The uric acid levels, initial hearing threshold, rate of hyperuricemia, and TC were lower in the good recovery group than the poor recovery group both in female and male patients. Binary logistic regression results showed that uric acid levels, initial hearing threshold, and hyperuricemia were associated with hearing recovery. CONCLUSION: Hyperuricemia might be an independent risk factor for hearing recovery in SSNHL patients. Serum uric acid and initial hearing threshold possibly affected the hearing outcome in males and females with SSNHL. LEVEL OF EVIDENCE: Level 4.

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BACKGROUND: Increased serum urate (SU) and hyperuricemia (HU) are associated with chronic noncommunicable diseases and mortality. SU concentrations are affected by several factors, including diet, and are expected to rise with age. We investigated whether the Dietary Approaches to Stop Hypertension (DASH) diet alter this trend. OBJECTIVE: The objective was to assess whether adherence to the DASH diet predicts a longitudinal change in SU concentrations and risk of HU in 8 y of follow-up. METHODS: Longitudinal analyses using baseline (2008-2010, aged 35-74 y), second (2012-2014), and third (2016-2018) visits data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil). The inclusion criteria were having complete food frequency questionnaire (FFQ) and urinary sodium measurement, in addition to having SU measurement at the 1st visit and at least 1 of the 2 follow-up visits. For the HU incidence analyses, participants had also to be free from HU at baseline. The final samples included 12575 individuals for the SU change analyses and 10549 for the HU incidence analyses. Adherence to DASH diet was assessed as continuous value. HU was defined as SU>6.8 mg/dL and/or urate-lowering therapy use. Mixed-effect linear and Poisson regressions (incidence rate ratio [IRR] and 95% confidence interval [CI]) were used in the analyses, adjusted for confounders. RESULTS: The mean age was 51.4 (8.7) y, and 55.4% were females. SU means (standard deviation) were 5.4 (1.4) at 1st visit, 5.2 (1.4) at 2nd visit, and 5.1(1.3) mg/dL at 3rd visit. The HU incidence rate was 8.87 per 1000 person-y. Each additional point in adherence to the DASH diet accelerated SU decline (P< 0.01) and lowered the incidence of HU by 4.3% (IRR: 0.957; 95% CI: 0.938,0.977) in adjusted model. CONCLUSION: The present study findings reinforce the importance of encouraging the DASH diet as a healthy dietary pattern to control and reduce the SU concentrations and risk of HU.

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