Since the outbreak of coronavirus disease (COVID-19) in Wuhan in December 2019, by March 10, 2020, a total of 80,932 confirmed cases have been reported in China. Two consecutively negative RT-PCR test results in respiratory tract specimens is required for the evaluation of discharge from hospital, and oropharyngeal swabs were the most common sample. However, false negative results occurred in the late stage of hospitalization, and avoiding false negative result is critical essential. We reviewed the medical record of 353 patients who received tests with both specimens simultaneously, and compared the performance between nasopharyngeal and oropharyngeal swabs. Of the 353 patients (outpatients, 192; inpatients, 161) studied, the median age was 54 years, and 177 (50.1%) were women. Higher positive rate (positive tests/total tests) was observed in nasopharyngeal swabs than oropharyngeal swabs, especially in inpatients. Nasopharyngeal swabs from inpatients showed higher positive rate than outpatients. Nasopharyngeal swabs from male showed higher positive rate than female, especially in outpatients. Detection with both specimens slightly increased the positive rate than nasopharyngeal swab only. Moreover, the consistency between from nasopharyngeal and oropharyngeal swabs were poor (Kappa=0.308). In conclusion, our study suggests that nasopharyngeal swabs may be more suitable than oropharyngeal swab at this stage of COVID-19 outbreak.

Vitamin D might have beneficial potential in influencing the natural history of the coronavirus disease 2019 (COVID-19) due to its immunomodulatory and anti-inflammatory properties. The aim was to investigate whether vitamin D deficiency is associated with COVID-19 incidence and disease severity in Chinese people. In a cross-sectional study we retrospectively analyzed 335 COVID-19 patients (median: 56.0; IQR: 43.0-64.0 y) who were admitted to the Wuhan Tongji Hospital between 27 February and 21 March 2020. We also included an age- and sex-matched population of 560 individuals (median: 55; IQR: 49.0-60.0 y) who underwent the physical examination program. Their serum 25-hydroxyvitamin D [25(OH)D] concentrations were measured during the same period from 2018-2019. Serum 25(OH)D concentrations were measured for all COVID-19 patients on admission. Severity of COVID-19 was determined based on the level of respiratory involvement. A general linear model with adjustment for covariates was used to compare 25(OH)D concentrations between the COVID-19 and 2018-2019 control groups. Adjusted ORs with 95% CIs for associations between vitamin D status and COVID-19 severity were estimated via multivariable logistic regression. In the general linear model adjusted for age, sex, comorbidities, and BMI, serum 25(OH)D concentrations were significantly lower among COVID-19 patients than the 2018-2019 controls [ln transformed values of 3.32 ± 0.04 vs. 3.46 ± 0.022 ln (nmol/L), P = 0.014]. Multivariable logistic regression showed that male sex (OR: 2.26; 95% CI: 1.06, 4.82), advanced age (≥65 y) (OR: 4.93; 95% CI: 1.44, 16.9), and vitamin D deficiency (<30 nmol/L) (OR: 2.72; 95% CI: 1.23, 6.01) were significantly associated with COVID-19 severity (all P < 0.05). These findings suggested that vitamin D deficiency impacts COVID-19 hospitalization and severity in the Chinese population.

The genetic origins of nanoscale extracellular vesicles in our body fluids remains unclear. Here, we perform a tracking analysis of urinary exosomes via RNA sequencing, revealing that urine exosomes mostly express tissue-specific genes for the bladder and have close cell-genetic relationships to the endothelial cell, basal cell, monocyte, and dendritic cell. Tracking the differentially expressed genes of cancers and corresponding enrichment analysis show urine exosomes are intensively involved in immune activities, indicating that they may be harnessed as reliable biomarkers of noninvasive liquid biopsy in cancer genomic diagnostics and precision medicine.

The variations and dynamics of essential and toxic metal(loid)s in patients with COVID‐19 may associate with the progression and fatal outcome of the disease, which still remains to investigate. In the present study, a retrospective analysis was performed in a cohort of 306 confirmed COVID‐19 patients admitted to Tongji hospital (Wuhan, China) from February 10 to March 15, 2020. Whole blood levels of essential and/or toxic metal(loid)s were analyzed, including magnesium, calcium, chromium, manganese, iron, copper, zinc, arsenic, cadmium, mercury, thallium, and lead according to the disease severity and outcome. Compared to the non‐severe COVID‐19 patients, severe cases showed significant higher levels of whole blood calcium, chromium, and copper, but lower levels of magnesium, manganese, iron, zinc, arsenic, thallium, and lead. These differences were further found consistently across the clinical course since the disease onset by longitudinal analysis. Among the severe patients, chromium and cadmium were higher in the deceased group compared to the recovered group, while arsenic was lower. Whole blood iron, age, and sex were determined to be independent factors associated with the disease severity, while chromium, cadmium, and the comorbidity of cardiovascular disease were determined to be independent factors associated with the mortality. These results suggest that variations of whole blood metal(loid)s may be associated with the severe illness and fatal outcome of COVID‐19, which could be persistently monitored and would be helpful in the evaluation of the dynamic changes in patients with COVID‐19.

Detecting small molecules is pivotal across fields like clinical diagnostics, environmental monitoring, and food safety. The CRISPR-Cas12a system, known for its simplicity and sensitivity, offers a promising basis for small molecule detection. However, current CRISPR-based detection methods face challenges, including complex design requirements, high background noise, and limited adaptability to different targets. In our study, we introduce the SBS-Cas system, leveraging a split crRNA mode to induce spatial hindrance on the scaffold strand through molecular binding. This approach prevents the assembly with Cas12a, effectively masking its trans-cleavage activity. By introducing small molecules that competitively bind to the macromolecule, we eliminate this spatial hindrance, activating Cas12a. Our results demonstrate high sensitivity, versatility, and adaptability in small molecule detection across multiple reactions, with successful intracellular imaging and responsive fluctuations in complex environments underscoring the system’s robustness. This innovative CRISPR-Cas12a-based approach establishes a low-background, highly sensitive platform for small molecule detection. SBS-Cas promises not only to enhance tools for clinical, environmental, and food safety applications but also to advance CRISPR research, providing insights and expanding possibilities in molecular detection science.