Detection and complete genome sequence analysis of human adenovirus in children with acute diarrhea in Yunnan, China, 2015-2021

The aims of this study were to determine the distribution and prevalence of gastroenteritis caused by human adenovirus (HAdV) in children in Yunnan province, China, in 2015-2021 and to identify preventive measures that can be taken to reduce morbidity and mortality in children.HAdV is a significant agent of diarrhea in children, but limited data are available regarding the epidemiology and genetic diversity of HAdV in children with diarrhea in Yunnan province, China. A total of 1754 fecal samples were subjected to real-time RT-PCR to detect and quantify HAdV. Positive samples were further analyzed using next-generation sequencing (NGS), and epidemiological data were analyzed as well.1754 patients with diarrhea were enrolled, of which 1041 were male and 713 were female (M:F ratio: 1.46). Seventy-two stool samples out of 1754 (4.10%) were positive for HAdV. The detection rates of all age groups varied from 2.50-4.78%. The highest incidence of HAdV was observed in children under 2 years of age, especially in children 12-24 months-old. From 2015-2021, the annual detection rate ranged from 1.62-12.26%. HAdV was detected throughout the year, but with marked seasonality. Children were most likely to be positive for HAdV in June and November. We detected HAdV in 15.53% (16/103) of samples collected in June and in 8.19% (14/171) of those collected in November. The entire viral genome was successfully sequenced for 13 of the 72 HAdV-positive samples, and 76.92% (10/13) of these were classified as genotype F41 and 23.08% (3/13) were classified as genotype C2.ConclusionsIn Yunnan province, children of all ages are susceptible to HAdV infection, but there has been marked variation in the yearly prevalence. The highest rate of HAdV detection was in June, followed by November. Priority should be given to disease prevention over the development of targeted antiviral therapies, and effective vaccines for preventing HAdV diarrhea are needed. It is also important to establish a surveillance system to collect relevant clinical and epidemiological data quickly in order to assess the potential risk of HAdV infection in children and to identify epidemic strains for the development of effective vaccines.

Long-term follow-up of resection of primary benign right ventricular tumours: a 10-year surgical experience

INTRODUCTION

Primary benign right ventricular tumours are rare. They can cause significant mortality without appropriate and timely treatment. We investigated surgical treatment and survival characteristics for right ventricular tumours.

MATERIALS AND METHODS

From 2007 to 2017, 21 patients with primary benign right ventricular tumours who underwent tumour resection were retrospectively reviewed. Clinical findings and follow-up results were analysed.

RESULTS

Thirteen men and eight women were enrolled, with a mean age of 42.3 ± 15.3 years. The most frequent histotypes were myxoma, haemangioma and papillary fibroelastoma. Eight patients underwent concomitant tricuspid valvuloplasty and one had tricuspid valve replacement. No major adverse events or death occurred during the perioperative period. One patient with haemangioma underwent partial tumour resection; however, the tumour regressed gradually during follow-up. Within the 10-year follow-up period (mean 4.8 ± 2.6 years), the recurrence-free and overall survival rates were 81.0% and 85.7%, respectively.

CONCLUSIONS

Tumour resection for primary benign right ventricular tumours is safe and effective, and has a good prognosis. Tricuspid valvuloplasty or tricuspid valve replacement may be necessary for the resection of right ventricular tumours to improve the haemodynamics. Haemangiomas naturally undergo spontaneous regression.

The impact of letter spacing on reading: a test of the bigram coding hypothesis

Identifying letters and their relative positions is the basis of reading in literate adults. The Local Combinations Detector model hypothesizes that this ability results from the general organization of the visual system, whereby object encoding proceeds through a hierarchy of neural detectors that, in the case of reading, would be tuned to letters, bigrams, or other letter combinations. Given the increase of receptive fields by a factor of 2 to 3 from one neural level to the next, detectors should integrate information only for letters separated by at most 2 other characters. We test this prediction by measuring the impact of letter spacing on reading, purifying this effect from confounding variables. We establish that performance deteriorates non-linearly whenever letters are separated by at least 2 blank spaces, with the concomitant emergence of a word length effect. We then show that this cannot be reduced to an effect of physical size nor of visual eccentricity. Finally, we demonstrate that the threshold of about 2 spaces is constant across variations in font size. Those results support the hypothesis that the fast recognition of combinations of nearby letters plays a central role in the coding of words, such that interfering with this representation prevents the parallel analysis of letter strings.