Prevalence and risk factor for long COVID in children and adolescents: A meta-analysis and systematic review.

BACKGROUND: Millions of COVID-19 pediatric survivors are facing the risk of long COVID after recovery from acute COVID-19. The primary objective of this study was to systematically review the available literature and determine the pooled prevalence of, and risk factors for long COVID among the pediatric survivors. METHODS: Studies that assessed the prevalence of, or risk factors associated with long COVID among pediatric COVID-19 survivors were systematically searched in PubMed, Embase, and Cochrane Library up to December 11th, 2022. Random effects model was performed to estimate the pooled prevalence of long COVID among pediatric COVID-19 patients. Subgroup analyses and meta-regression on the estimated prevalence of long COVID were performed by stratification with follow-up duration, mean age, sex ratio, percentage of multisystem inflammatory syndrome, hospitalization rate at baseline, and percentage of severe illness. RESULTS: Based on 40 studies with 12,424 individuals, the pooled prevalence of any long COVID was 23.36 % ([95 % CI 15.27-32.53]). The generalized symptom (19.57 %, [95 % CI 9.85-31.52]) was reported most commonly, followed by respiratory (14.76 %, [95 % CI 7.22-24.27]), neurologic (13.51 %, [95 % CI 6.52-22.40]), and psychiatric (12.30 %, [95% CI 5.38-21.37]). Dyspnea (22.75 %, [95% CI 9.38-39.54]), fatigue (20.22 %, [95% CI 9.19-34.09]), and headache (15.88 %, [95 % CI 6.85-27.57]) were most widely reported specific symptoms. The prevalence of any symptom during 3-6, 6-12, and> 12 months were 26.41 % ([95 % CI 14.33-40.59]), 20.64 % ([95 % CI 17.06-24.46]), and 14.89 % ([95 % CI 6.09-26.51]), respectively. Individuals with aged over ten years, multisystem inflammatory syndrome, or had severe clinical symptoms exhibited higher prevalence of long COVID in multi-systems. Factors such as older age, female, poor physical or mental health, or had severe infection or more symptoms were more likely to have long COVID in pediatric survivors. CONCLUSIONS: Nearly one quarter of pediatric survivors suffered multisystem long COVID, even at 1 year after infection. Ongoing monitoring, comprehensive prevention and intervention is warranted for pediatric survivors, especially for individuals with high risk factors.

Impact of body mass index on primary immunoglobulin A nephropathy prognosis: a systematic review and meta-analysis.

PURPOSE: The impacts of body mass index (BMI) on the prognosis of primary IgA nephropathy (IgAN) remain controversial. This systematic review and meta-analysis aimed to solve these issues. METHODS: We searched the PubMed, EMBASE, and Cochrane Library to screen articles investigating the BMI and primary IgAN. BMI was classified according to the World Health Organization as high (≥ 25.0 kg/m2) and low (< 25.0 kg/m2). The baseline renal indexes and the incidences of adverse renal outcomes were focused on. RESULTS: Six studies with a total of 1723 patients were included in this study. High BMI was demonstrated to be associated with increased baseline levels of serum creatinine (weighted mean difference (WMD) 9.54, 95% confidence interval (CI) 0.63-18.45), blood uric acid (WMD 19.85, 95% CI 10.11-29.59) and urine protein (WMD 0.37, 95% CI 0.21-0.53). Patients with high BMI also showed compromised eGFR at diagnosis (WMD - 8.39, 95% CI - 11.62 to - 5.16) with a higher incidence rate of hypertension (odds ratios (OR) 2.59, 95% CI 1.44-4.66) and higher global optical scores (WMD 1.22, 95% CI 0.70-1.74). Regarding the prognosis, high BMI was significantly associated with the incidence of adverse renal outcomes (OR 2.43, 95% CI 1.66-3.55, P < 0.001) and deteriorated eGFR at the last follow-up (WMD - 11.10, 95% CI - 16.96 to - 5.25, P < 0.001), with non-significantly poorer renal disease-free survival (hazard ratio 1.79, 95% CI 0.58-5.50, P = 0.31). CONCLUSION: High BMI was associated with severe onset and poor prognosis of primary IgAN. The management of BMI could be a novel method to promote the therapeutic outcomes of primary IgAN.

Carbon nanotube-based flexible electrothermal film heaters with a high heating rate.

High-performance, flexible film heaters with carbon nanotube transparent conducting films are easily fabricated by both a rod-coating method and a spraying method. The main conclusion we have reached is that the film demonstrates a heating rate of 6.1°C s-1 at 35 V and sheet resistance as low as 94.7 Ω sq-1 with 72.04% optical transmittance at a wavelength of 550 nm by the spraying method after a series of post-treatment processes with acid and distilled water. Then, we adopt a mathematical method of nonlinear fitting to simulate the collected experimental data and the functions effectively. Furthermore, through analysis of the formula, the correlation between temperature and time is well explained. Therefore, carbon nanotube-based, flexible, transparent heaters exhibit high electrothermal performance and are expected to find different applications, e.g. various functional devices such as heating materials, heatable smart windows or dining tables.

[Significance of serum cholesterol and fibrinogen in evaluating the risk of glomerulosclerosis in children with nephrotic syndrome].

OBJECTIVE: To investigate the significance of serum cholesterol and fibrinogen (Fib) in evaluating the risk of glomerulosclerosis in children with nephrotic syndrome. METHODS: Sixty-three children with primary nephrotic syndrome were divided into two groups according to their pathological types: minimal change glomerulopathy (MCG) (n=39) and focal segmental glomerulosclerosis (FSGS) groups (n=24). Serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-HDL-C and Fib and 24-hour urinary protein excretion were retrospectively analyzed. RESULTS: Serum levels of TC, non-HDL-C, and LDL-C were significantly higher in the FSGS group than in the MCG group (P<0.05), but there were no significant differences in HDL-C, Fib and 24-hour urinary protein excretion between the two groups (P>0.05). According to the results of logistic regression analysis, high levels of LDL-C, non-HDL-C and TC were risk factors for FSGS (P<0.05). In patients whose proteinuria did not disappear after taking enough glucocorticoid for 4 weeks, the level of non-HDL-C was significantly higher in the FSGS group than in the MCG group (P<0.05); there were no significant differences in TC, LDL-C, HDL-C, and Fib between the MCG and FSGS groups (P>0.05). CONCLUSIONS: Serum cholesterol, especially non-LDL-C, is of great significance in evaluating the risk of glomerulosclerosis in children with nephrotic syndrome. There is no sufficient evidence to support serum Fib as a marker for predicting glomerulosclerosis in these children.

[A clinico-pathological comparison between Henoch-Schonlein purpura nephritis and IgA nephropathy in children].

OBJECTIVE: To study the difference in clinico-pathological features between IgA nephropathy (IgAN) and Henoch-Schonlein purpura nephritis (HSPN) in children. METHODS: The medical data of 103 children with HSPN and 61 children with IgAN were retrospectively studied. RESULTS: There were no significant differences in age, sex and disease course between the HSPN and IgAN groups (P>0.05). Clinical classification demonstrated that more severe conditions were found in the IgAN group than in the HSPN group and gross hematuria was more common in the IgAN group (P<0.05). Serum creatinine and cholesterol levels were higher in the IgAN group than in the HSPN group (P<0.05). Fibrinogen-related antigen deposition was more common in the HSPN group, while complement 3(C3) deposition was more common in the IgAN group. Interstitial fibrosis, tubular casts and tubular inflammatory infiltration were also more common in the IgAN group (P<0.05). CONCLUSIONS: Significant clinico-pathological differences can be found between HSPN and IgAN in children, and these differences do not support a one disease entity hypothesis.

Improved color rendering of phosphor-converted white light-emitting diodes with dual-blue active layers and n-type AlGaN layer.

An InGaN/GaN blue light-emitting diode (LED) structure and an InGaN/GaN blue-violet LED structure were grown sequentially on the same sapphire substrate by metal-organic chemical vapor deposition. It was found that the insertion of an n-type AlGaN layer below the dual blue-emitting active layers showed better spectral stability at the different driving current relative to the traditional p-type AlGaN electron-blocking layer. In addition, color rendering index of a Y3Al5O12:Ce3+ phosphor-converted white LED based on a dual blue-emitting chip with n-type AlGaN reached 91 at 20 mA, and Commission Internationale de L'Eclairage coordinates almost remained at the same point from 5 to 60 mA.