Promoter Methylation of QKI as a Potential Specific Biomarker for Early Detection of Colorectal Cancer

Early and specific detection of cancer provides an opportunity for appropriate treatment. Although studies have suggested that QKI is a tumor suppressor gene, no studies have evaluated the diagnostic utility of QKI methylation in colorectal cancer (CRC). Here, we evaluated the methylation status of QKI by integrating the methylation data of tissues and cell lines of multiple cancer types. The diagnostic performance of QKI was analyzed in the discovery dataset from the TCGA CRC 450K array (n = 440) and tested in the test sets (n = 845) from the GEO. The methylation level of QKI was further validated in our independent dataset (n = 388) using targeted bisulfite sequencing. All detected CpG sites in the QKI promoter showed CRC-specific hypermethylation in 31 types of tumor tissues. In the discovery dataset, six consecutive CpG sites achieved high diagnostic performances, with AUCs ranging from 0.821 to 0.930. In the test set, a region (chr6: 163,834,452–163,834,924) including four consecutive CpG sites had robust diagnostic ability in distinguishing CRC and adenoma from normal samples. In the validation dataset, similar robust results were observed in both early- and advanced-stage CRC patients. In addition, QKI exhibited hypermethylation in the cfDNA of patients with CRC (n = 14). Collectively, the QKI promoter is a CRC-specific methylation biomarker and holds great promise for improving the diagnosis using minimally invasive biopsy.

Polymeric immunoglobulin receptor suppresses colorectal cancer through the AKT-FOXO3/4 axis by downregulating LAMB3 expression

Colorectal cancer (CRC) remains one of the most common malignancies worldwide and its mechanism is unclear. Polymeric immunoglobulin receptor (PIGR) which plays an important role in mucosal immunity is widely expressed in the mucosal epithelium and is dysregulated in different tumors. However, the role and underlying mechanisms of PIGR in CRC remain unclear. Here, we demonstrated that PIGR was hypermethylated and downregulated in our cohort (N = 272), and these features were associated with reduced overall survival in patients (HRmethylation 1.61, 95% CI [1.11-2.33]). These findings were validated by external TCGA and GEO data. Moreover, PIGR overexpression inhibits CRC cell malignant phenotypes in vitro and impedes CRC cells growth in male BALB/c nude mice. Mechanistically, PIGR physically associates with RE1 silencing transcription factor (REST) and blocks the transcription of laminin subunit beta 3 (LAMB3). Subsequently, the AKT-FOXO3/4 axis was suppressed by downregulated LAMB3. In the drug sensitive assay, PIGR-overexpressing cells were more sensitive to cisplatin and gemcitabine. Together, PIGR may serve as a powerful prognostic biomarker and putative tumor suppressor by suppressing the AKT-FOXO3/4 axis by downregulating LAMB3 in CRC. Our study may offer a novel therapeutic strategy for treating CRC patients who highly express PIGR with cisplatin and gemcitabine.

[Occurrence and recovery of adverse drug reactions of preventive treatment in elderly population with latent tuberculosis infection]

Objective: To evaluate the occurrence and recovery of adverse drug reactions (ADRs) of preventive treatment in the elderly population with latent tuberculosis infection (LTBI). Methods: A total of 2 583 elderly patients with LTBI were recruited in Zhongmu, Henan Province from July 1 to October 17, 2015. Face-to-face surveys and physical examinations were used to obtain the basic information of the participants, and the body mass index (BMI) was calculated. Fasting venous blood was collected from the participants for blood biochemical and routine blood tests. The random numbers were generated by Excel 2010, and the participants were divided into group A (1 284 cases) and group B (1 299 cases) by simple randomization. Both group A and group B received combination treatment of isoniazid and rifapentine. Group A was treated for 8 weeks with weekly doses of isoniazid at 15 mg/kg and 900 mg for those with body weight ≤50 and>50 kg, respectively, and the doses of rifapentin were 750 and 900 mg, respectively. Group B was treated twice a week for 6 weeks, the doses of isoniazid in patients with body weight ≤50 and>50 kg were [600-(50-body weight)×15] (rounded up) and 600 mg, respectively, and the doses of rifapentin were 600 and 450 mg, respectively. During the treatment period, doctors observed, inquired about and recorded symptoms related to ADRs, and blood biochemical and routine blood tests were performed at 4 weeks after taking the drug, the end of the treatment, and 3 months after the end of the treatment. The patients with ADRs were treated accordingly by severity. The ADRs and graded treatment outcomes of LTBI patients in group A and group B were compared. Results: The age［M（Q₁，Q₃）］of the participants was 60 (55,65) years old, and 54.7% (1 412/2 583) were males. There were no statistical differences in age, gender, BMI and baseline biochemical indexes between groups A and B (all P values>0.05). The incidence of ADRs in group A and group B were 18.5% (237/1 279) and 16.3% (209/1 279), respectively, and those with alanine aminotransferase (ALT)≥5 ULN accounted for 0.8% (7/931) and 1.1% (11/987), aspartate aminotransferase (AST)≥5 ULN accounted for 0.3% (3/931) and 0.3% (3/987), respectively, and there were no statistically significant differences (all P values>0.05). There were 7 and 11 patients with ALT≥5 ULN in group A and group B, respectively, and 3 patients with AST≥5 ULN for each group, respectively. After treatment, except for 2 patients with ALT≥5 ULN in group B, ALT and AST levels in all the other patients returned to normal. There were 15 and 10 patients with abnormal white blood cell count in group A and group B, respectively, and 10 and 9 patients returned to normal after treatment. Conclusion: LTBI preventive treatment has a high incidence of adverse drug reactions, but it can be effectively controlled through active monitoring and graded management.

Decreased Serum Exosomal microRNA-134 Expression and Its Prognostic Value in Gastric Cancer

OBJECTIVE

Identification of reliable biomarkers for the diagnosis and prognosis of gastric cancer (GC) is very important for achieving early cancer detection and improving clinical outcomes. The aim of the present study was to explore the clinical significance of serum exosomal miR-134 in GC.

METHODS

A total of 133 GC cases were enrolled in this study, and quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) was carried out to measure the relative serum exosomal miR-134 expression level. The association between serum exosomal miR-134 expression and clinicopathological characteristics was investigated.

RESULTS

Our results showed that serum exosomal miR-134 expression was significantly lower in GC patients than in controls. In addition, serum exosomal miR-134 discriminated GC cases from healthy controls with high accuracy. Moreover, reduced serum exosomal miR-134 expression was closely associated with aggressive clinical variables including TNM stage, lymph node metastasis and invasion depth. Furthermore, Kaplan-Meier analysis revealed that GC patients with low serum exosomal miR-134 expression tended to have shorter overall survival and relapse free survival. In multivariate analysis, serum exosomal miR-134 was an independent prognostic marker for GC.

CONCLUSION

In conclusion, serum exosomal miR-134 might serve as a promising diagnostic and prognostic biomarker for GC.

[Status of HVPG clinical application in China in 2021]

Objective: The investigation and research on the application status of Hepatic Venous Pressure Gradient (HVPG) is very important to understand the real situation and future development of this technology in China. Methods: This study comprehensively investigated the basic situation of HVPG technology in China, including hospital distribution, hospital level, annual number of cases, catheters used, average cost, indications and existing problems. Results: According to the survey, there were 70 hospitals in China carrying out HVPG technology in 2021, distributed in 28 provinces (autonomous regions and municipalities directly under the central Government). A total of 4 398 cases of HVPG were performed in all the surveyed hospitals in 2021, of which 2 291 cases (52.1%) were tested by HVPG alone. The average cost of HVPG detection was (5 617.2±2 079.4) yuan. 96.3% of the teams completed HVPG detection with balloon method, and most of the teams used thrombectomy balloon catheter (80.3%). Conclusion: Through this investigation, the status of domestic clinical application of HVPG has been clarified, and it has been confirmed that many domestic medical institutions have mastered this technology, but it still needs to continue to promote and popularize HVPG technology in the future.

POS0005 BASELINE BIOMARKERS PREDICT BETTER RESPONSES TO DEUCRAVACITINIB, AN ORAL, SELECTIVE TYROSINE KINASE 2 (TYK2) INHIBITOR, IN A PHASE 2 TRIAL IN PSORIATIC ARTHRITIS

Background

Deucravacitinib (DEUC) is a novel, oral, selective TYK2 inhibitor with a unique allosteric mechanism of action that has demonstrated efficacy in patients with psoriasis (PsO)1 and psoriatic arthritis (PsA).2 TYK2 mediates signalling of select immune cytokines, eg, interleukin (IL) 23, IL-12, and Type I interferons, whereas the related Janus kinases (JAK) 1/2/3 mediate signalling of a wider array of cytokines and mediators involved in inflammatory, developmental, metabolic, and hematopoietic pathways. DEUC reduced inflammatory markers associated with skin and joint manifestations but did not result in laboratory abnormalities associated with inhibition of JAK1/2/3 in a PsA trial.3

Objectives

To identify baseline biomarkers that predict response to DEUC in patients with PsA.

Methods

The double-blind Phase 2 trial (NCT03881059) enrolled 203 patients with PsA randomised 1:1:1 to placebo (PBO), DEUC 6 mg once daily (QD), or 12 mg QD.2 Molecular profiling of baseline serum samples was performed by immunoassays. Clinical response at Week 16 was measured by ≥20% improvement from baseline in American College of Rheumatology Improvement Criteria (ACR 20) and ≥75% improvement from baseline in Psoriasis Area and Severity Index (PASI 75) scores.

Results

Biomarkers of the IL-23/T helper cell type 17 pathway, including IL-17A, IL-17‒induced β-defensin 2 (BD2), and IL-19, were associated with higher PASI but not Psoriatic Arthritis Disease Activity Scores overall at baseline. PASI 75 responders in DEUC-treated groups had higher baseline levels of IL-17A compared with nonresponders. In contrast, PASI 75 responders in PBO-treated patients had lower baseline expression of IL-17A, BD2, and IL-19 compared with nonresponders. In patients treated with DEUC 12 mg QD, greater reductions in BD2 were observed in the PASI 75 responder group compared with nonresponder group. When patients were dichotomised by median baseline biomarker level, higher clinical responses in both PASI 75 and ACR 20 were achieved in those with higher baseline overall biomarker levels in the DEUC-treated groups compared with the PBO group. Higher baseline expression of IL-23 biomarkers IL-17A, IL-19, and BD2 enriched ACR 20 response in patients treated with DEUC compared with PBO (OR=5.64, 6.68, and 4.99, respectively). While greater benefit was observed in high-biomarker groups, the low-biomarker populations still manifested clinical responses although not significant (Figure 1).

Conclusion

Patients who had higher expression of IL-23 pathway biomarkers were more likely to benefit from DEUC compared with placebo in skin and joint manifestations of PsA. These results reinforce the value of TYK2 inhibition in patients with IL-23‒mediated diseases. The potential value of IL-23-pathway markers in predicting higher responses to DEUC should be further explored in larger trials.

References

[1]Armstrong A et al. Presented at American Academy of Dermatology Virtual Meeting Experience 2021; April 23-25, 2021.

[2]Mease PJ et al. Efficacy and Safety of Selective TYK2 Inhibitor, Deucravacitinib, in a Phase 2 Trial in Psoriatic Arthritis. Ann Rheum Dis. (In Press).

[3]FitzGerald O et al. Presented at the 2021 ACR Convergence, American College of Rheumatology; Nov 3-9, 2021.

Acknowledgements

This study was sponsored by Bristol Myers Squibb. Professional medical writing assistance was provided by Julianne Hatfield, PhD at Peloton Advantage, LLC, an OPEN Health company, Parsippany, NJ, USA, and funded by Bristol Myers Squibb.

Disclosure of Interests

Oliver FitzGerald Consultant of: Consulting and/or speaker fees: Biogen, and Novartis., Grant/research support from: Research grants: BMS, Novartis, Pfizer, UCB, Lilly., Dafna D Gladman Consultant of: Consulting fees: AbbVie, Amgen, BMS, Galapagos, Gilead, Eli Lilly, Janssen, Novartis, Pfizer, and UCB., Grant/research support from: Research grants: AbbVie, Amgen, Eli Lilly, Janssen, Novartis, Pfizer, and UCB, Philip J Mease Consultant of: Consulting and/or speaker fees: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myers Squibb, Eli Lilly, Galapagos, Gilead, GlaxoSmithKline, Janssen, Novartis, Pfizer, SUN Pharma, and UCB., Grant/research support from: Research grants: AbbVie, Amgen, Boehringer Ingelheim, Bristol Myers Squibb, Eli Lilly, Galapagos, Gilead, GlaxoSmithKline, Janssen, Novartis, Pfizer, SUN Pharma, and UCB, Christopher T. Ritchlin Consultant of: Consultant: AbbVie, Amgen, Janssen, Lily, Novartis, Pfizer, Regeneron, Sun, UCB;, Grant/research support from: Grants / Research Support: AbbVie, Amgen, UCB, Josef S. Smolen Consultant of: Consulting and/or speaker fees: AbbVie, Amgen, Bristol Myers Squibb, Eli Lilly, Galapagos-Gilead, Janssen, Merck-Sharp-Dohme, Novartis-Sandoz, Pfizer, Roche-Chugai, Samsung, and UCB., Grant/research support from: Research grants: AbbVie, AstraZeneca, Eli Lilly, Novartis, Lu Gao Shareholder of: Bristol Myers Squibb., Employee of: Bristol Myers Squibb., Sarah Hu Shareholder of: Bristol Myers Squibb., Employee of: Bristol Myers Squibb., Miroslawa Nowak Shareholder of: Bristol Myers Squibb., Employee of: Bristol Myers Squibb., Subhashis Banerjee Shareholder of: Bristol Myers Squibb., Employee of: Bristol Myers Squibb., Ian Catlett Shareholder of: Bristol Myers Squibb., Employee of: Bristol Myers Squibb.

[COVID-19 vaccines primary features and research progress on possible trigger of liver injury post-vaccination]

The COVID-19 outbreak is a global pandemic that has had caused a profound impact on social stability, economic development and national security, and has further evolved into a major public health crisis. The rapid research and development and efficient deployment of vaccines is one of the effective means to prevent and control the epidemic. This article reviews the primary features of current COVID-19 vaccines, simultaneously focus the clinical features of liver injury post-vaccination and explore its possible pathogenesis.

[Waxing and waning pulmonary nodules and cavities]

We reported a case of vascular Ehlers-Danlos syndrome presenting with recurrent pulmonary hemorrhage. A 22-year-old man was admitted for intermittent hemoptysis and chest pain during the past 18 months. Computed tomography of chest showed bilateral nodules and cavities with halo sign. Inflammatory markers, including erythrocyte sedimentation rate, C reactive protein and interleukin 6, were within normal range. The microbiological and pathological examination of bronchoalveolar lavage fluid and CT-guided percutaneous lung biopsy failed to draw a diagnosis. The pulmonary lesions waxed and waned despite empirical antibacterial, antifungal, antimycobacterial, and anti-parasite treatment. Video-assisted thoracoscopic lung biopsy showed pulmonary hemorrhage, hematoma, ossification, and fibrous nodules, suggesting vascular Ehlers-Danlos syndrome. The molecular testing revealed a heterozygous missense variant in the COL3A1 gene which confirmed the diagnosis of vascular Ehlers-Danlos syndrome. The patient had no skin hyperextensibility or joint hypermobility. During 3-year follow-up, there were no evidence of other vascular or organ involvement except he had intermittent minor hemoptysis. Through this clinical pathological discussion, we aimed to remind pulmonologist to consider the possible diagnosis of vascular Ehlers-Danlos syndrome in young patients with recurrent hemoptysis and waxing and waning pulmonary nodules, cavities, or cysts on CT scan who has neither obvious systematic inflammation nor effective reaction on empirical antimicrobial therapy. Molecular testing should be carried out as soon as possible in a suspected patient to avoid unnecessary invasive examinations.

[Subcutaneous nodules, mediastinal and hilar lymphadenopathy]

A 52-year old man was admitted to our hospital because of dyspnea on exertion for 2 months and subcutaneous nodules for 1 month. Chest enhanced CT showed bilateral hilar and mediastinal lymphadenopathy. Bronchial alveolar lavage fluid revealed a CD₄⁺/CD₈⁺ T cell subsets ratio of 4.3 and culture for acid-fast bacillus (AFB) was negative. The pathology of skin nodules and transbronchial needle aspiration biopsy guided by endoscopic ultrasound (EBUS-TBNA) revealed non-caseating necrotizing epithelioid granulomas with negative acid-fast bacilli staining and periodic acid-Schiff staining, which was compatible with sarcoidosis. The patient was diagnosed as sarcoidosis and glucocorticoid was administrated. The subcutaneous nodules were improved. However, the lymph nodes were enlarged instead of shrinking after 6-month therapy. The failure to respond to glucocorticoids raised the possibility of sarcoidosis complicated with tuberculosis infection. The patient received anti-tuberculosis therapy. Lymphadenopathy responded within 4 months, and there was complete regression after 18-month treatment. The patient was followed up for 5 years and repeated chest CT scan showed that the sizes of bilateral hilar and mediastinal lymph nodes were normal.

[Treatment and prognosis analysis of perineural invasion on sinonasal adenoid cystic carcinoma]

Objective: To analyze the efficacy of sinonasal adenoid cystic carcinoma (ACC) with perineural invasion (PNI), and explore the prognostic value of PNI on sinonasal adenoid cystic carcinoma. Methods: The clinical data of 105 patients with sinonasal ACC admitted to Cancer Hospital, Chinese Academy of Medical Sciences from January 2000 to December 2016 were retrospectively reviewed. All patients were restaged according to American Joint Committee on Cancer 8th edition. Follow-up visits were conducted to obtain information of treatment failure and survival outcome. The Log rank test was used for univariate analysis of prognostic factors, and Cox regression model was used for multivariate prognostic analysis. Results: The maxillary sinus (n=59) was the most common primary site, followed by the nasal cavity (n=38). There were 93 patients with stage Ⅲ-Ⅳ. The treatment modalities included surgery alone (n=14), radiotherapy alone (n=13), preoperative radiotherapy plus surgery (n=10), and surgery plus postoperative radiotherapy (n=68). The median follow-up time was 91.8 months, the 5-year local control (LC), distant metastasis-free survival (DMFS), progression-free survival (PFS), and overall survival (OS) rates were 72.6%, 73.0%, 52.9% and 78.0%, respectively. There were 33 patients (31.4%) with PNI-positive. The 5-year DMFS, PFS, and OS rates of PNI-positive group were 53.7%, 29.4% and 56.5%, respectively, which were significantly inferior to those of PNI-negative group (80.8%, 63.0% and 86.8%, respectively, P<0.05), while there was no significant difference in the 5-year LC rate between both groups (64.5% vs 76.5%, P=0.273). The multivariate Cox regression analysis showed PNI was one of the poor prognostic factors of DMFS (HR=3.514, 95%CI: 1.557-7.932), PFS (HR=2.562, 95%CI: 1.349-4.866) and OS (HR=2.605, 95%CI: 1.169-5.806). Among patients with PNI-positive, the 5-year LC, PFS and OS rates of patients received surgery combined with radiotherapy were 84.9%, 41.3% and 72.7%, respectively, which were significantly higher than 23.3%, 10.0% and 26.7% of patients receiving surgery or radiotherapy alone (P<0.05). Conclusion: The presence of PNI increases the risk of distant metastasis in patients with sinonasal ACC. Compared with patients with PNI-negative, the prognosis of patients with PNI-positive is relatively poor, and surgery combined with radiotherapy for PNI-positive sinonasal ACC results in good clinical outcomes.

Synthesis of aluminum alkylphosphinates under atmospheric pressure

Alkylphosphinates have received extensive attention in the past few decades because of their very useful mechanical properties, electrical properties, low density, and low toxicity, and have been widely used in flame-retardant materials and other fields. In this work, aluminum diethylphosphinate is successfully synthesized under atmospheric pressure. More importantly, two novel dialkylphosphinates, aluminum dioctylphosphinate and aluminum didecylphosphinate, are first synthesized and characterized. The structures of these aluminum dialkylphosphinates are confirmed by nuclear magnetic resonance, Fourier-transform infrared spectroscopy, and high-resolution mass spectrometry, and the microscopic morphology and thermal stability are analyzed by scanning electron microscopy and thermogravimetric analysis, respectively. Furthermore, conditions for the synthesis of aluminum dioctylphosphinate are optimized. Compared with the traditional method of synthesizing dialkylphosphinates under high pressure, the method reported in this paper has the advantages of high safety, easy operation, and low economic cost, which makes it suitable for industrial production.

Echinacoside inhibited cardiomyocyte apoptosis and improved heart function in heart failure rats induced by isoproterenol via suppressing nadph/ros/atf6/chop associated endoplasmic reticulum stress

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): Shaanxi Provincial Key Research and Development Projects (2019SF-218)

Background

Endoplasmic reticulum (ER) stress played an essential role in the development and progression of HF due to it could induce cardiomyocyte apoptosis, ATF6/CHOP was regulated by NADPH and ROS and was the crucial pathway to link ER stress and apoptosis in HF. Our previous study indicated that ECH reversed cardiac remodeling and improves heart function, but the underlying mechanisms are still unclear.

Objectives

To investigate the effect of ECH on cardiomyocyte apoptosis and endoplasmic reticulum stress and the underlying mechanisms.

Methods

In vitro, we cultured AC-16 cells and induced cell damage and ER stress by ISO, treated by ECH, the cell apoptosis and biomarkers of ER stress (GRP78, ATF6α, IRE1α, PERK) were detected. In vivo, we induced HF rat model by ISO and treated by ECH, indexes of heart function, cardiomyocyte apoptosis, biomarkers of ER stress and NADPH/ROS/ATF6/CHOP pathway were measured.

Results

In vitro, we confirmed that ECH inhibited ER stress and apoptosis. In vivo, we demonstrated that ECH inhibited cardiomyocyte apoptosis and improved heart function, it significantly decreased GRP78, ATF6α, IRE1α, PERK, and down-regulated NADPH/ROS/ATF6/CHOP pathway.

Conclusions

ECH inhibited cardiomyocyte apoptosis and improved heart function via suppressing NADPH/ROS/ATF6/CHOP pathway associated ER stress.

[Gasless submental-transoral combined appoach endoscopic thyroidectomy for papillary thyroid carcinoma: a series of 41 cases]

Objective: To examine the safety and feasibility of gasless submental-transoral combined appoach endoscopic thyroidectomy for papillary thyroid carcinoma (PTC). Methods: A retrospective analysis of the clinical data of 41 patients with PTC who underwent the gasless submental-transoral combined appoach endoscopic thyroidectomy at the Department of Head and Neck Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine from November 2020 to April 2021. There were 5 males and 36 females with the age of (35.0±8.7) years (range: 19 to 58 years). A horizontal incision with a length of 2.0 cm is made under the chin as an observation hole, a 10 mm Trocar and a self-developed retractor are inserted, and two 5 mm longitudinal incisions are made on the labial side in the vestibule of the oral cavity as an operation hole, each inserting a 5 mm Trocar, the operation direction is from the cranial side to the caudal side. The sensation of the lower lip and chin was measured on the first day and one month postoperative. The operation time, hospital stay, the number of lymph nodes dissected and postoperative complications were recorded. Results: Surgical procedures in all cases were successfully completed under endoscopic approach without transfering to open surgery. The operation time was (99±34) minutes (range: 50 to 180 minutes) and the postoperative hospital stay was (3.4±2.2) days (range: 2 to 16 days). The maximum diameter of PTC was (7.6±5.8) mm (range: 2 to 30 mm), and the number of lymph nodes of the central compartment dissection was 6(5) (M(IQR)) (range: 1 to 25). The duration of follow-up is 1 month after operation, and the follow-up method is adopted in outpatient clinic. Postoperation complications included 2 cases of transient hypoparathyroidism, One case of recurrent laryngeal nerve injury (continue to follow up to assess whether it is a temporary injury). Postoperative minor chyle leak, seroma, and local redness and swelling in 1 case each were cured after conservative treatment. 1 case of transient minor numbness of the lower lip was observed. No permanent hypoparathyroidism, postoperative bleeding and numbness of the chin was observed. Conclusion: The gasless submental-transoral combined appoach endoscopic thyroidectomy is a feasible approach in selected PTC patients and has clinical application value.

[A short half-life of cccDNA offer or ignite hope for hepatitis B cure under nucleos(t)ide analogues treatment]

Covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is the template for HBV replication. Currently, there is a lack of therapeutic drugs that directly target cccDNA. Therefore, blocking cccDNA supplements as fast as possible and reducing the existing cccDNA is the key to achieving a complete cure of chronic hepatitis B. Previous studies have suggested that cccDNA had a long half-life, but a recent study showed that it only took a few months to update cycle of cccDNA pool, and its number was much less than previously predicted. In the future, with the advent of new antiviral drugs that can completely inhibit HBV replication, it is expected that the cccDNA pool will be completely cleared due to its supplement complete blockade, so as to achieve virological cure of chronic hepatitis B.

Association between Dietary Theobromine and Cognitive Function in a Representative American Population: A Cross-Sectional Study

BACKGROUND

Despite reports on neuroprotective effects of dietary theobromine intake, whether dietary theobromine has beneficial effects on cognitive function is unclear.

OBJECTIVES

To investigate the association between dietary theobromine and cognitive function.

DESIGN

A cross-sectional study.

SETTING

Data were collected from the 2011-2014 cycles of the National Health and Nutrition Examination Survey conducted by the Centers for Disease Control and Prevention of the USA.

PARTICIPANTS

A representative American population aged ≥60 years.

MEASUREMENTS

L-theobromine was treated as a log transform and dichotomous form (the highest quantile vs. others). Cognitive function was measured using four tests: Consortium to Establish a Registry for Alzheimer's Disease Word Learning tests, Consortium to Establish a Registry for Alzheimer's Disease delayed recall test, animal fluency test, and digit symbol substitution test. We conducted multiple regression analyses and subgroup analyses to study the association between theobromine and cognitive performance. Basic characteristics, lifestyle factors, disease history, and nutritional intake were adjusted for in these models.

RESULTS

A total of 2,845 participants were included in the study. The highest quantile of L-theobromine intake was positively associated with sores of delayed recall, animal fluency, and digit symbol substitution tests (β, 95% confidence interval, P: 0.11, -0.00-0.30, 0.049; 0.50, 0.02-0.99, 0.043; 1.55, 0.33-2.77, 0.015; respectively) in the fully adjusted model, but not with immediate recall score (β=0.13, 95% confidence interval -0.16-0.43, P=0.361). Subgroup analyses showed that L-theobromine intake was associated with cognitive performance in the highest quantile of caffeine intake.

CONCLUSIONS

Daily theobromine intake was associated with cognitive performance in a large nationally representative population. However, further research is needed to corroborate our findings.

Optofluidic Resonance of a Transparent Liquid Jet Excited by a Continuous Wave Laser

We report a new optofluidic resonating phenomenon that naturally links the optical radiation pressure, total internal reflection, capillary wave, and Rayleigh-Plateau instability together. When a transparent liquid jet is radiated by a focused continuous wave laser beam, the highly ordered periodic jet breakup is unexpectedly triggered and maintained. The capillary wave enables the liquid-gas interface to serve as a rotating mirror reflecting the laser beam in a wide range of angles, including the critical angle for total internal reflection. The liquid jet acts as an optical waveguide to periodically transmit the laser beam to the upstream of the jet. The periodic optical beam transmittance inside the liquid jet exerts time-dependent optical pressure to the jet that triggers the Rayleigh-Plateau instability. The jet breakup process locks in at the frequency corresponding to the peak growth rate of the Rayleigh-Plateau instability of the liquid jet, which agrees with the prediction from the dispersion relation of a traveling liquid jet.

[Microscopic observation of the enamel microstructures of SD rats with different degrees of fluorosis]

Objective: To establish a dental fluorosis model of SD rats with various degrees, to observe the microstructures of enamel samples under scanning electron microscope and to clarify the changes of enamel microstructures with various degrees of dental fluorosis, so as to provide clinical reference for the treatment of patients with moderate and severe dental fluorosis. Methods: Thirty male SD rats (6 weeks of age) were randomly divided into 3 groups with 10 rats in each group. The control group was fed with deionized water without fluoride, the low fluoride group was fed with 50 mg/L NaF deionized water and the high fluoride group was fed with 100 mg/L NaF deionized water in order to establish the dental fluorosis model of rats. After feeding for 6 weeks, the rats were sacrificed and the mandibular incisor teeth were collected and recorded. The surface and sagittal plane of each tooth were observed by scanning electron microscopy and the enamel thickness was measured. Results: In the control group, the enamel color was brown yellow. Enamel color discoloration occurred both in low-fluoride group and high-fluoride group. The enamel color in low-fluoride group was mostly yellow and white striped while in high-fluoride group was mostly chalky white. Under electronic microscope, the enamel rods were alternately arranged and their structure was clear and plump in the control group. The enamel rods of moderate fluorosis were arranged in a straight orientation like tips of bamboo shoots. The enamel rods of severe fluorosis, however, became thinner and the tips of rods were broken. In the control group, sagittal images of enamel turned out to be a dense outer structure with clear boundaries among the inner. The structure of the middle layer was reticulated showing a clear boundary with middle and outer layers. The structure of enamel rods in the inner layers was arranged vertically and horizontally. In the moderate fluorosis group, the outer layer of the enamel became thinner and the middle layer disappeared although the boundary between the outer and middle layers was still clear. In the inner layer, the vertically arranged enamel rods seemed still clear, however the horizontal enamel rods disappeared. In the severe fluorosis group, the outer layer could not be traced. The middle layer was exposed to the air and the inner enamel rods contracted. The inner layers of the enamel had gradually become thinner with the development of the dental fluorosis. The thicknesses of inner layers in control, moderate and the severe groups were (180.71±7.01), (157.10±11.04) and (121.10±12.56) μm respectively. As for the thicknesses of the full layers in the above mentioned three groups, the same trend was observed. The thicknesses, in order of the severity of dental fluorosis, were (241.54±7.76), (207.42±14.36) and (143.79±14.60) μm. Conclusions: With the development of dental fluorosis, the outer enamel layers became thinner or disappeared and the inner enamel layers became thinner or lost its normal structure as well. It is highly recommended that the resin penetration could be used for the proper treatment of moderate and severe dental fluorosis and the strong bleaching and the micro-grinding should be used cautiously.