Oleanolic acid derivative alleviates cardiac fibrosis through inhibiting PTP1B activity and regulating AMPK/TGF-ß/Smads pathway.

Cardiac fibrosis (CF) in response to persistent exogenous stimuli or myocardial injury results in cardiovascular diseases (CVDs). Protein tyrosine phosphatase 1B (PTP1B) can promote collagen deposition through regulating AMPK/TGF-ß/Smads signaling pathway, and PTP1B knockout improves cardiac dysfunction against overload-induced heart failure. Oleanolic acid (OA) has been proven to be an inhibitor of PTP1B, and its anti-cardiac remodeling effects have been validated in different mouse models. To improve the bioactivity of OA and to clarify whether OA derivatives with stronger inhibition of PTP1B activity have greater prevention of cardiac remodeling than OA, four new OA derivatives were synthesized and among them, we found that compound B had better effects than OA in inhibiting cardiac fibrosis both in vivo in the isoproterenol (ISO)-induced mouse cardiac fibrosis and in vitro in the TGF-ß/ISO-induced 3T3 cells. Combining with the results of molecular docking, surface plasmon resonance and PTP1B activity assay, we reported that OA and compound B directly bound to PTP1B and inhibited its activity, and that compound B showed comparable binding capability but stronger inhibitory effect on PTP1B activity than OA. Moreover, compound B presented much greater effects on AMPK activation and TGF-ß/Smads inhibition than OA. Taken together, OA derivative compound B more significantly alleviated cardiac fibrosis than OA through much greater inhibition of PTP1B activity and thus much stronger regulation of AMPK/TGF-ß/Smads signaling pathway.

Mechanism and Association between Microbial Nitrogen Transformation in Rhizosphere and Accumulation of Ciprofloxacin in Choysum (Brassica parachinensis).

Rhizosphere microbiota are an important factor impacting plant uptake of pollutants. However, little is known about how microbial nitrogen (N) transformation in the rhizosphere affects the uptake and accumulation of antibiotics in plants. Here, we determined recruitment of N transformation functional bacteria upon ciprofloxacin (CIP) exposure, by comparing differences in assembly processes of both rhizospheric bacterial communities and N transformation between two choysum (Brassica parachinensis) varieties differing in CIP accumulation. The low accumulation variety (LAV) of CIP recruited more host bacteria (e.g., Nitrospiria and Nitrolancea) carrying nitrification genes (mainly nxrA) but fewer host bacteria carrying denitrification genes, especially narG, relative to the high accumulation variety (HAV) of CIP. The nxrA and narG abundance in the LAV rhizosphere were, respectively, 1.6-7.8 fold higher and 1.4-3.4 fold lower than those in the HAV rhizosphere. Considering that nitrate can decrease CIP uptake into choysum through competing for the proton motive force and energy, such specific bacteria recruitment in LAV favored the production and utilization of nitrate in its rhizosphere, thus limiting its CIP accumulation with 1.6-2.4 fold lower than the HAV. The findings give insight into the mechanism underlying low pollutant accumulation, filling the knowledge gap regarding the profound effects of rhizosphere microflora and N transformation processes on antibiotic accumulation in crops.

Substrate-enzyme interactions and catalytic mechanism in a novel family VI esterase with dibutyl phthalate-hydrolyzing activity.

Microbial degradation has been confirmed as effective and environmentally friendly approach to remediate phthalates from the environment, and hydrolase is an effective element for contaminant degradation. In the present study, a novel dibutyl phthalate (DBP)-hydrolyzing carboxylesterase (named PS06828) from Pseudomonas sp. PS1 was heterogeneously expressed in E. coli, which was identified as a new member of the lipolytic family VI. Purified PS06828 could efficiently degrade DBP with a wide range of temperature (25-37 °C) and pH (6.5-9.0). Multi-spectroscopy methods combined with molecular docking were employed to study the interaction of PS06828 with DBP. Fluorescence and UV-visible absorption spectra revealed the simultaneous presence of static and dynamic component in the fluorescence quenching of PS06828 by DBP. Synchronous fluorescence and circular dichroism spectra showed inconspicuous alteration in micro-environmental polarity around amino acid residues but obvious increasing of α-helix and reducing of ß-sheet and random coil in protein conformation. Based on the information on exact binding sites of DBP on PS06828 provided by molecular docking, the catalytic mechanism mediated by key residues (Ser113, Asp166, and His197) was proposed and subsequently confirmed by site-directed mutagenesis. The results can strengthen our mechanistic understanding of family VI esterase involved in hydrolysis of phthalic acid esters, and provide a solid foundation for further enzymatic modification.

An inner-filter-effect based ratiometric fluorescent sensor for the detection of uranyl ions in real samples.

In this work, a ratiometric fluorescence system was designed for the detection of trace UO22+ in water based on the inner filter effect (IFE) between gold nanoparticles (AuNPs) and gold nanoclusters (AuNCs). IFE-induced fluorescence quenching was achieved due to the enhanced complementary overlap between the absorption spectra of AuNPs and the emission spectrum of AuNCs after the addition of UO22+. Blue carbon dots (B-CDs) were added to serve as reference fluorophores to expand the color tonality and make human eye recognition easier. The ratiometric fluorescent sensor demonstrated a unique fluorescence color change from red to blue when different doses of UO22+ were added, with a detection limit of 8.4 nM. Furthermore, the ratiometric fluorescent sensor was effectively used for UO22+ determination in real-world water samples, with acceptable recoveries.

Foreign Direct Investment, Regional Innovation, and Green Economic Efficiency: An Empirical Test Based on the Investigation of Intermediary Effect and Threshold Effect.

Based on the theoretical mechanism analysis of FDI, regional innovation, and green economic efficiency, this article uses China's provincial panel data to calculate the provincial green economic efficiency level based on the three-stage DEA method and uses the system GMM model, intermediary effect model, and threshold model to empirically test the specific effects and transmission paths of FDI on the efficiency of the green economy. Research shows that FDI is one of the important factors that promote the improvement of green economic efficiency. Subregional tests have found that FDI has a significant regional heterogeneity in promoting the efficiency of the green economy. The mediation effect test found that the mediation effect of regional innovation is significant, and FDI can significantly promote the growth of green economic efficiency through regional innovation. The threshold effect analysis found that there are significant and effective double thresholds for regional economic levels, and the impact of FDI on green economic efficiency is heterogeneous within different threshold intervals. The research conclusions provide new inspiration for China to allocate FDI more rationally and efficiently under the new development pattern.

Dynamic Measurement and Structural Decomposition of Deep Poverty in Contiguous Destitute Areas.

Based on the sample data from 2005 to 2019, this paper calculates the poverty nature of contiguous destitute areas through FGT index and its decomposition and systematically analyzes the impact of economic growth, inequality, and population change on poverty change. From the decomposition results of poverty change, we can see that, first, economic growth, inequality, and population change have different impacts on poverty change in counties and rural areas, and inequality and population mobility have widened the gap between them; second, population factor has always played a key role in the change of poverty, and the deceleration of population growth has a more significant impact on poverty change; third, the impact of the mobility on the poverty change of the counties is different from that of the rural areas. Accordingly, the paper puts forward some countermeasures and suggestions, such as promoting the organic connection between rural revitalization and poverty alleviation, speeding up rural governance, and promoting the process of urbanization.

Alport syndrome combined with lupus nephritis in a Chinese family: A case report.

BACKGROUND: Alport syndrome (ATS) is a rare hereditary disease caused by mutations in genes such as COL4A3, COL4A4, and COL4A5. ATS involves a spectrum of phenotypes ranging from isolated hematuria that is nonprogressive to progressive renal disease with extrarenal abnormalities. Although ATS can be combined with other diseases or syndromes, ATS combined with lupus nephritis has not been reported before. CASE SUMMARY: A Chinese family with ATS was recruited for the current study. Clinical characteristics (including findings from renal biopsy) of ATS patients were collected from medical records, and potential causative genes were explored by whole-exome sequencing. A heterozygous substitution in intron 22 of COL4A3 (NM_000091 c.2657-1G>A) was found in the patients, which was further confirmed by quantitative polymerase chain reaction. CONCLUSION: Heterozygous substitution of a COL4A3 gene splice site was identified by whole-exome sequencing, revealing the molecular pathogenic basis of this disorder. In general, identification of pathogenic genes can help to fully understand the molecular mechanism of disease and facilitate precise treatment.

Detection of genes responsible for cetuximab sensitization in colorectal cancer cells using CRISPR-Cas9.

Colorectal cancer (CRC) is a common malignant tumor in digestive tract with highly invasive and metastatic capacity. Drug sensitivity remains a significant obstacle to successful chemotherapy in CRC patients. The present study aimed to explore genes related to cetuximab (CTX) sensitivity in CRC by clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9. Celigo image cytometer was used to detect suitable cells and optimal dosage of CTX. Inhibition rate of CTX on Caco-2 cells was evaluated by cell counting kit-8 (CCK-8) method before and after transfection. 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide (MTT) was performed to explore suitable concentration of puromycin and multiplicity of infection (MOI). CRISPR-Cas9, sequencing data quality analysis and cell viability test were used for the selection of genes related to CTX sensitivity in CRC cells. Finally, the selected genes associated with CTX sensitivity in CRC cells were further validated by colony formation and CCK-8 assays. In the present study, Caco-2 cells had a better prolificacy, and CTX 100 µg/ml exhibited a good inhibition trend on the 7th and 14th days of infection. MTT assay indicated that the minimum lethal concentration of puromycin was 2.5 µg/ml. Forty-six candidate genes were preliminarily screened via sequencing data quality analysis. Subsequently, we found that knockout of any of the four genes (MMP15, MRPL48, CALN1 and HADHB) could enhance CTX sensitivity in Caco-2 cells, which was further confirmed by colony formation assay. In summary, MMP15, MRPL48, CALN1 and HADHB genes are related to the mediation of CTX sensitivity in CRC.

Synthesis and biological evaluation of substituted pyrrolidines and pyrroles as potential anticancer agents.

A series of polysubstituted pyrrolidines obtained via ruthenium-catalyzed cascade cyclization of diazo pyruvates and anilines as well as their corresponding pyrrole analogs obtained via dehydration were evaluated for their antiproliferation activities. Pyrrolidines 3h and 3k showed good proliferation inhibitory effects toward 10 cancer cell lines with IC50 values ranging from 2.9 to 16 µM. Furthermore, pyrrolidine 3k induced cell cycle arrest at the G0/G1 phase and time- and dose-dependent cellular apoptosis in both HCT116 and HL60 cells, suggesting that this type of pyrrolidine structure might be a good candidate for future anticancer therapies.

Role of miR-124 in the regulation of retinoic acid-induced Neuro-2A cell differentiation.

Retinoic acid can cause many types of cells, including mouse neuroblastoma Neuro-2A cells, to differentiate into neurons. However, it is still unknown whether microRNAs (miRNAs) play a role in this neuronal differentiation. To address this issue, real-time polymerase chain reaction assays were used to detect the expression of several differentiation-related miRNAs during the differentiation of retinoic acid-treated Neuro-2A cells. The results revealed that miR-124 and miR-9 were upregulated, while miR-125b was downregulated in retinoic acid-treated Neuro-2A cells. To identify the miRNA that may play a key role, miR-124 expression was regulated by transfection of miRNA mimics or inhibitors. Morphological analysis results showed that inhibition of miR-124 expression reversed the effects of retinoic acid on neurite outgrowth. Moreover, miR-124 overexpression alone caused Neuro-2A cells to differentiate into neurons, and its inhibitor could block this effect. These results suggest that miR-124 plays an important role in retinoic acid-induced differentiation of Neuro-2A cells.

Comparison of laparoscopic and open surgery in treatment of rectal cancer patients / 中国内镜杂志

Objective To compare the effect of laparoscopic and open surgery in treatment of rectal cancer. Methods 80 cases of patients with rectal cancer from May 2008 to May 2013 were selected, they were randomly divided into laparoscopy surgery group (n = 40) and open surgery group (n = 40), the operation time, intraoperative blood loss, length of incision, lymph node dissection, number for the first time, ventilation time, ambulation time, hospitalization time, cost of hospitalization, postoperative complications, treatment satisfaction of the two groups were statistically analyzed. Results The operation time of the laparoscopic surgery group was significantly longer (P < 0.05), the amount of bleeding was significantly less (P < 0.05), the incision length was significantly shorter (P < 0.05), the first time, ventilation time, ambulation time, hospitalization time were significantly shorter (P < 0.05), the hospitalization cost was significantly higher (P < 0.05), the rate of postoperative complications 15.0% (6/40) was significantly lower than the open surgery group 35.0% (14/40) (P < 0.05) 97.5% (39/40), the treatment satisfaction was significantly higher than the open surgery group 67.5% (27/40)(P < 0.05). Conclusion The effect of laparoscopic and open surgery in treatment of rectal cancer is better than open surgery.

Dodecahedral W@WC Composite as Efficient Catalyst for Hydrogen Evolution and Nitrobenzene Reduction Reactions.

Core-shell composites with strong phase-phase contact could provide an incentive for catalytic activity. A simple, yet efficient, H2O-mediated method has been developed to synthesize a mesoscopic core-shell W@WC architecture with a dodecahedral microstructure, via a one-pot reaction. The H2O plays an important role in the resistance of carbon diffusion, resulting in the formation of the W core and W-terminated WC shell. Density functional theory (DFT) calculations reveal that adding W as core reduced the oxygen adsorption energy and provided the W-terminated WC surface. The W@WC exhibits significant electrocatalytic activities toward hydrogen evolution and nitrobenzene electroreduction reactions, which are comparable to those found for commercial Pt/C, and substantially higher than those found for meso- and nano-WC materials. The experimental results were explained by DFT calculations based on the energy profiles in the hydrogen evolution reactions over WC, W@WC, and Pt model surfaces. The W@WC also shows a high thermal stability and thus may serve as a promising more economical alternative to Pt catalysts in these important energy conversion and environmental protection applications. The current approach can also be extended or adapted to various metals and carbides, allowing for the design and fabrication of a wide range of catalytic and other multifunctional composites.

Dual ALK and CDK4/6 Inhibition Demonstrates Synergy against Neuroblastoma.

Purpose: Anaplastic lymphoma kinase (ALK) is the most frequently mutated oncogene in the pediatric cancer neuroblastoma. We performed an in vitro screen for synergistic drug combinations that target neuroblastomas with mutations in ALK to determine whether drug combinations could enhance antitumor efficacy.Experimental Design: We screened combinations of eight molecularly targeted agents against 17 comprehensively characterized human neuroblastoma-derived cell lines. We investigated the combination of ceritinib and ribociclib on in vitro proliferation, cell cycle, viability, caspase activation, and the cyclin D/CDK4/CDK6/RB and pALK signaling networks in cell lines with representative ALK status. We performed in vivo trials in CB17 SCID mice bearing conventional and patient-derived xenograft models comparing ceritinib alone, ribociclib alone, and the combination, with plasma pharmacokinetics to evaluate for drug-drug interactions.Results: The combination of ribociclib, a dual inhibitor of cyclin-dependent kinase (CDK) 4 and 6, and the ALK inhibitor ceritinib demonstrated higher cytotoxicity (P = 0.008) and synergy scores (P = 0.006) in cell lines with ALK mutations as compared with cell lines lacking mutations or alterations in ALK Compared with either drug alone, combination therapy enhanced growth inhibition, cell-cycle arrest, and caspase-independent cell death. Combination therapy achieved complete regressions in neuroblastoma xenografts with ALK-F1174L and F1245C de novo resistance mutations and prevented the emergence of resistance. Murine ribociclib and ceritinib plasma concentrations were unaltered by combination therapy.Conclusions: This preclinical combination drug screen with in vivo validation has provided the rationale for a first-in-children trial of combination ceritinib and ribociclib in a molecularly selected pediatric population. Clin Cancer Res; 23(11); 2856-68. ©2016 AACR.

Utility of Red Cell Distribution Width as a Prognostic Factor in Young Breast Cancer Patients.

The prognosis of breast cancer occurs in young women is usually poor. Red cell distribution width (RDW), 1 of many routinely examined parameters, has recently been proposed as a prognostic marker in solid tumors. The aim of our study was to assess the predictive value of RDW for survival in young women with breast cancer.We reviewed 203 consecutive young female patients (under 40) with invasive breast cancer diagnosed at the First Affiliated Hospital of Wenzhou Medical University between January 2008 and December 2012. Preoperational RDW, clinicopathological information, and prognostic data were collected. RDW levels were divided into 2 groups: 161 patients with low RDW (≤13.75%) and 42 patients with high RDW (>13.75%). Clinicopathological differences between the 2 groups were calculated by chi-squared test and Wilcoxon rank-sum test. Kaplan-Meier survival analysis and Cox proportional hazard regression analyses were used to examine the effect of RDW on survival.We found that high RDW was significantly associated with larger tumor size (P = 0.002), positive lymph node metastases (P = 0.011), and advanced stages (P = 0.004). Patients with high RDW showed significantly lower disease-free survival (DFS; P < 0.001) and lower overall survival (OS) rate (P < 0.001) than patients with low RDW. Moreover, the Cox regression multivariate analysis revealed that high pretreatment DRW was independently correlated with poor DFS and OS, with hazard ratio 4.819 (95% confidence interval [CI] 2.291-10.138, P < 0.001) and 5.887 (95% CI 1.666-20.802, P = 0.006), respectively.In conclusion, our study demonstrated that pretreatment RDW may be associated with DFS and OS in young women with breast cancer. Further validation and feasibility studies are required before the result of our study can be considered for clinical practice.

Methanol electro-oxidation on platinum modified tungsten carbides in direct methanol fuel cells: a DFT study.

In exploration of low-cost electrocatalysts for direct methanol fuel cells (DMFCs), Pt modified tungsten carbide (WC) materials are found to be great potential candidates for decreasing Pt usage whilst exhibiting satisfactory reactivity. In this work, the mechanisms, onset potentials and activity for electrooxidation of methanol were studied on a series of Pt-modified WC catalysts where the bare W-terminated WC(0001) substrate was employed. In the surface energy calculations of a series of Pt-modified WC models, we found that the feasible structures are mono- and bi-layer Pt-modified WCs. The tri-layer Pt-modified WC model is not thermodynamically stable where the top layer Pt atoms tend to accumulate and form particles or clusters rather than being dispersed as a layer. We further calculated the mechanisms of methanol oxidation on the feasible models via methanol dehydrogenation to CO involving C-H and O-H bonds dissociating subsequently, and further CO oxidation with the C-O bond association. The onset potentials for the oxidation reactions over the Pt-modified WC catalysts were determined thermodynamically by water dissociation to surface OH* species. The activities of these Pt-modified WC catalysts were estimated from the calculated kinetic data. It has been found that the bi-layer Pt-modified WC catalysts may provide a good reactivity and an onset oxidation potential comparable to pure Pt and serve as promising electrocatalysts for DMFCs with a significant decrease in Pt usage.

The Effect of Flattening Filter Free on Three-dimensional Conformal Radiation Therapy (3D-CRT), Intensity-Modulated Radiation Therapy (IMRT), and Volumetric Modulated Arc Therapy (VMAT) Plans for Metastatic Brain Tumors from Non-small Cell Lung Cancer.

Flattening filter free (FFF) may affect outcome measures of radiotherapy. The objective of this study is to compare the dosimetric parameters in three types of radiotherapy plans, three-dimensional conformal radiation therapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and volumetric modulated arc therapy (VMAT), with or without the flattening filter (FF), developed for the treatment of metastatic brain tumors from non-small cell lung cancer (NSCLC). From July 2013 to October 2013, 3D-CRT, IMRT, and VMAT treatment plans were designed using 6 MV and 10 MV, with and without FF, for 10 patients with brain metastasis from NSCLC. The evaluation of the treatment plans included homogeneity index (HI), conformity index (CI), monitor units (MU), mean dose (Dmean), treatment time, and the influence of FFF on volumes. There was no difference in CI or HI between FFF and FF models with 3D-CRT, IMRT, and VMAT plans. At 6 MV, a lower Dmean was seen in the FFF model of 3D-CRT and in the VMAT plan at 10 MV. In the IMRT 6 MV, IMRT 10 MV, and VMAT 10 MV plans, higher MUs were seen in the FFF models. FFF treatments are similar in quality to FF plans, generally lead to more monitor units, and are associated with shorter treatment times. FFF plans ranked by the order of superiority in terms of a time advantage are VMAT, 3D-CRT, and IMRT.

[Ambulatory arterial stiffness index and associated factors in patients with diabetic kidney disease].

OBJECTIVE: To compare arterial stiffness between diabetic kidney disease and non-diabetic kidney diseaseand to identify factors predicting ambulatory arterial stiffness index (AASI). METHODS: Forty-four patients with diabetic kidney disease (DKD group) and thirty-one patients with non-diabetic kidney disease (NDKD group) were recruited for this study. All of the participants had hypertension. The AASI (indirect reflex global arterial stiffness)and short-term blood pressure variability (BPV) were measured using a 24-h ambulatory BP monitoring, and compared.between DKD and NDKD groups using analyses of covariance, correlation analysis and multivariate linear regression model. RESULTS: DKD patients had significantly higher levels of AASI than NDKD patients (0.55 +/- 0.14 vs. 0.45 +/- 0.16, P < 0.05). The 24-h systolic and daytime systolic BP variability of DKD patients was also higher than NDKD patients. In DKD patients, the correlation analysis revealed that the AASI showed association with 24-h systolic BP variability (24 hSBPV), 24-h diastolic BP variability (24 hDBPV),daytime diastolic BP variability (dDBPV), nighttime systolic BP variability (nSBPV) and nighttime diastolic BP variability (nDBPV), and nDBPV and age showed strong associations with AASI. CONCLUSION: Although both DKD and NDKD patients suffered from arterial stiffness, greater AASI and short-term BPV was detected in DKD patients. AASI is associated with nDBPV and age. Optimal short-term BPV control in hypertensive type 2 diabetic patients with overt nephropathy may improve arterial elasticity.

[Analysis of lorentzian line shape function broadened by non-sinusoidal wavelength modulation].

In the present work, the Fourier analysis of Lorentzian line shape broadened by non-sinusoidal wavelength modulation was investigated, in which the third order and above harmonic items were ignored. The analytical expression of n-order Fourier coefficient was brought out, where a variable K named harmonic distortion to characterize the ratio of the second harmonic to the first harmonic was introduced. Numerical simulations based on the cases of K > 0.01 and K < 0.01 were carried out, and the result shows: non-sinusoidal modulation has little effect compared with the sinusoidal modulation when K value is less than 0.01, however, if K value is about 0.1 or higher, the center of the Fourier amplitude curve would deviate from the origin of coordinates. With the increase in the harmonic distortion, the deviation of the curve grows, and high order harmonics are more sensitive to the non-sinusoidal modulation compared with the low order harmonics. In addition, when harmonic distortion cannot be ignored, for example K > 0.01, the effect of different depths of modulation on the odd and even order harmonic amplitude curve is significant. And the numerical simulation shows there exists an optimum value of modulation depth which could minimize the impact of the harmonic distortion, and both large K value and small K value would cause a great error. The conclusion of this work could be applied in error analysis of wavelength modulation spectroscopy system And the results are helpful to deepening understanding of WMS and would be the important reference for some kind of frequency stabilization technology in laser instrument.

Prognostic value of circulating microRNA-21 in digestive system cancers: a meta-analysis.

UNLABELLED: Circulating microRNAs show aberrant expression in patients with cancer. The aim of this study was to investigate the prognostic value of circulating microRNA-21 (miR-21) in digestive system cancers. METHODS: All the eligible studies were searched by Medline and EMBASE. The hazard ratios (HRs) for overall survival (OS), which compared the expression levels of circulating miR-21 in patients with digestive cancer was extracted and estimated. Pooled HRs and 95% confidence intervals (CI) were calculated. Then a meta-analysis was performed to clarify the prognostic value of the miR-21. RESULTS: A total of seven studies involving 907 subjects were included. The results suggested that higher circulating miR-21 could predict worse OS outcome with the pooled HR of 2.19 (95% CI 1.01-4.75, P = 0.05) in digestive system cancers. Subgroup analysis by ethnicity indicated circulating miR-21 was associated with OS in patients with digestive cancer among Asians with the pooled HR of 2.90 (95% CI 1.30-6.45, P = 0.009). However, subgroup analysis by digestive system site revealed that there is no associated with OS in patients with colorectal cancer with the pooled HR of 1.34 (95% CI 0.45-4.00, P = 0.60). CONCLUSION: The present findings suggest that circulating miR-21 is associated with poor survival in patients with digestive cancer and could be a prognostic biomarker for those patients.

Thymectomy in central lymph node dissection for papillary thyroid cancer.

BACKGROUND: Central lymph node dissection (CND) has been proposed in the treatment of patients affected by papillary thyroid cancer (PTC) with clinically negative neck lymph nodes. The procedure allows pathologic staging of lymph nodes of the central compartment and treatment of the micrometastases. By comparing bilateral and unilateral thymectomy during total thyroidectomy with central lymph node dissection for postoperative complications in sonographically node-negative papillary thyroid carcinomas, we aimed to determine the optimal extent of prophylactic central lymph node dissection. METHODS: Patients were divided into two study groups: Group 1, total thyroidectomy plus unilateral thymectomy during the CND; Group 2, total thyroidectomy associated with bilateral thymectomy (both upper poles) during the CND. Primary endpoints of the study were evaluated by comparing the postoperative complications between the two groups. RESULTS: The only significant result found when comparing the two groups was the rate of transient hypocalcemia. (Group 1: 13.7%, Group 2: 52.4%, p<0.01). A total of five cases of papillary thymic metastases were found in this study. And final pathology confirmed that all cases of thymic metastases were lymph node micrometastases of PTC, only situated in the ipsilateral thymus upper pole. CONCLUSIONS: Bilateral thymectomy during the CND did not provide a better carcinologic resection, as no contralateral thymic metastases were found. The unilateral thymectomy with total thyroidectomy during the CND may represent an effective strategy for reducing the rate of postoperative hypocalcemia.