An extracellular vesicle microRNA-initiated 3D DNAzyme motor for colorectal cancer diagnosis.

MicroRNA is regarded as a significant biomarker for cancer diagnosis, disease process evaluation and therapeutic guidance, and dual-parameter measurement may contribute to a more accurate and realistic assessment. To meet the urgent need for simultaneous detection of multiple biomarkers, we combined three-dimensional DNAzyme motors with single molecule imaging technique to construct a convenient, intuitive, and sensitive approach for the simultaneous detection of dual miRNAs in the free state or in extracellular vesicles. Quantification of target miRNAs can be realized through the detection of amplified fluorescence signals generated by the target miRNA-initiated cleavage of fluorescent substrate strands by the DNAzyme motors. The practicability was systematically validated with microRNA-21-5p and microRNA-10b-5p as targets, acquiring a satisfactory sensitivity sufficient to detect low abundance targets at 0.5 or 1 pM to 100 pM. Besides, the extracellular vesicular miRNAs can be conveniently detected without extraction. The clinical applicability was verified with a series of extracellular vesicles from clinical samples, which exhibited good distinguishability between colorectal cancer patients and healthy donors. In addition to the advantages of good specificity and high sensitivity, the system has potential to be easily adapted by minor alteration of the DNA sequences and fluorophore sets for detection of multiple miRNAs and even other types of biomarkers such as proteins. Therefore, it shows promise to be widely applied in various fields such as early diagnosis of cancer and its prognostic assessment.

Effect of the serum 25-hydroxyvitamin D level on risk for short-term residual dizziness after successful repositioning in benign paroxysmal positional vertigo stratified by sex and onset age.

Objective: A low serum 25-hydroxyvitamin D (25(OH)D) level is relevant to both the occurrence and recurrence of benign paroxysmal positional vertigo (BPPV). However, whether it also contributes to residual dizziness (RD) after successful repositioning maneuvers is unknown. Therefore, this study aimed to explore the correlation between the serum 25(OH)D level and short-term RD severity in patients with BPPV after successful repositioning maneuvers. Methods: In total, 251 patients with BPPV after successful repositioning were enrolled and prospectively followed up for 1 week (W1). Serum 25(OH)D values were detected by chemiluminescence immunoassay at enrollment (W0). In addition, we explored the relationship between 25(OH)D values at baseline and RD severity at W1 in different subgroups stratified by sex and onset age (early-onset, ≤50 years; late-onset, >50 years). Results: The serum 25(OH)D level of female patients was significantly lower than that of male patients (15.9 ± 6.8 vs. 19.8 ± 6.6 ng/ml, p < 0.001). Its level also decreased in early-onset patients compared to late-onset ones (15.3 ± 5.9 vs. 18.0 ± 7.3 ng/ml, p = 0.003). In addition, early-onset female patients had lower 25(OH)D values than late-onset female patients (14.0 ± 5.5 vs. 17.1 ± 7.2 ng/ml, p = 0.004). However, this difference was not observed between early- and late-onset male patients. Among early-onset female patients, the 25(OH)D values of the moderate-to-severe RD group were lower than those of the minor or no RD group (10.9 ± 3.3 vs. 14.7 ± 5.7 vs. 15.0 ± 5.9 ng/ml, p = 0.046). Multivariate analysis found that decreased 25(OH)D values were related to the occurrence of moderate-to-severe RD in early-onset female patients (OR = 0.801; p = 0.022). This effect did not exist in late-onset female or male patients with BPPV. Conclusions: Age and sex differences in serum 25(OH)D levels exist in patients with BPPV. A decreased 25(OH)D level in early-onset female patients may increase the odds of moderate-to-severe RD 1 week after successful repositioning maneuvers.

Clinical and cVEMP Evaluation Predict Short-Term Residual Dizziness After Successful Repositioning in Benign Paroxysmal Positional Vertigo.

Objective: Residual dizziness (RD) is a frequent symptom with unknown pathogenesis, often complained about by the patients with benign paroxysmal positional vertigo (BPPV), even after a successful canalith repositioning procedure (CRP). This study aims to quantitatively evaluate the short-term RD severity and its risk factors in patients with BPPV after successful CRPs. Methods: In total two hundred and twenty patients with BPPV after successful CRPs (W0) were prospectively followed up for 1 week (W1). Besides demographics and serial neuropsychological assessments (including dizziness handicap inventory-DHI, etc.), patients also received cervical/ocular vestibular evoked myogenic potential (c/oVEMP) evaluation. RD was defined as patients with dizziness or imbalance, dizziness visual analog scale (VAS) >1, and without positional vertigo or nystagmus at W1. Demographic, clinical, and VEMPs differences were compared among the three groups: patients with minor (dizziness VAS 1-3) and moderate-to-severe RD (dizziness VAS > 3) and without RD. Results: The total frequency of RD at W1 was 49.1% (n = 108), with 32.3% (n = 71) minor, and 16.8% (n = 37) moderate-to-severe RD. Logistic regression analyses revealed that RD was closely associated with DHI status (OR = 2.101, P = 0.008) at W0, this effect was not present for minor RD. In addition to DHI score > 30 (OR = 4.898, P < 0.001) at W0, bilateral cVEMP absence (OR = 4.099, P = 0.005) was also an independent influential factor of moderate-to-severe RD. Conclusion: Our study highlights the importance of RD quantified evaluation. DHI score >30 and bilateral cVEMP absence could increase the risk of short-term moderate-to-severe RD.

Seasonal variation of idiopathic benign paroxysmal positional vertigo correlates with serum 25-hydroxyvitamin D levels: a six-year registry study in Shanghai, China.

Seasonal variation of benign paroxysmal positional vertigo (BPPV) occurrence has been reported in recent years. Whether the seasonality of BPPV also exists in Chinese patients and whether it correlates with serum vitamin D levels is unexplored. We retrospectively analyzed the data of 1269 new-onset idiopathic BPPV patients registered in our vertigo outpatient clinic over a six-year period. Additionally, serum 25-hydroxyvitamin D levels during this period were measured in 877 patients by chemiluminescence immunoassay. We delineated the changing trend of the monthly BPPV patient numbers and serum 25-hydroxyvitamin D levels, and the correlation between them was explored. December to next March is the top 4 months with higher BPPV patient numbers. The median BPPV patient numbers in winter group were higher than those in summer group (20 vs. 16 patients, p < 0.05). Median 25-hydroxyvitamin D levels in winter group were much lower than those in summer group (16.3 vs. 20.8 ng/ml, p < 0.001) and autumn group (16.3 vs. 19.3 ng/ml, p < 0.05). A moderate negative correlation was observed between median serum 25-hydroxyvitamin D levels and BPPV patient numbers each month. The onset of BPPV also shows a seasonal fluctuation in Chinese patients. This phenomenon may be related to serum vitamin D levels.

Validation of 5-item and 2-item questionnaires in Chinese version of Dizziness Handicap Inventory for screening objective benign paroxysmal positional vertigo.

As possible candidate screening instruments for benign paroxysmal positional vertigo (BPPV), studies to validate the Dizziness Handicap Inventory (DHI) sub-scale (5-item and 2-item) and total scores are rare in China. From May 2014 to December 2014, 108(55 with and 53 without BPPV) patients complaining of episodic vertigo in the past week from a vertigo outpatient clinic were enrolled for DHI evaluation, as well as demographic and other clinical data. Objective BPPV was subsequently determined by positional evoking maneuvers under the record of optical Frenzel glasses. Cronbach's coefficient α was used to evaluate the reliability of psychometric scales. The validity of DHI total, 5-item and 2-item questionnaires to screen for BPPV was assessed by receiver operating characteristic (ROC) curves. It revealed that the DHI 5-item questionnaire had good internal consistency (Cronbach's coefficient α = 0.72). Area under the curve of total DHI, 5-item and 2-item scores for discriminating BPPV from those without was 0.678 (95 % CI 0.578-0.778), 0.873(95 % CI 0.807-0.940) and 0.895(95 % CI 0.836-0.953), respectively. It revealed 74.5 % sensitivity and 88.7 % specificity in separating BPPV and those without, with a cutoff value of 12 in the 5-item questionnaire. The corresponding rate of sensitivity and specificity was 78.2 and 88.7 %, respectively, with a cutoff value of 6 in 2-item questionnaire. The present study indicated that both 5-item and 2-item questionnaires in the Chinese version of DHI may be more valid than DHI total score for screening objective BPPV and merit further application in clinical practice in China.