Effects of organic zinc on tibia quality, mineral deposit, and metallothionein expression level of aged hens

The study aimed to determine the effects of methionine hydroxy analog chelate zinc on the tibia quality, mineral deposit, apparent retention of nutrients, and liver metallothionein (MT) expression level of aged laying hens. A total of 960 layers (Hy-Line Grey, 57 wk old) were randomly assigned into 4 groups, and each group had 8 replicates of 30 hens. During the first 2 wk, groups were fed a basal diet without extra zinc (Zn: 35.08 mg/kg). During the ensuing 14 wk, 4 levels of Zn (inorganic Zn: 80 mg/kg; organic Zn: 20, 40, 80 mg/kg) were added to the diet. The results indicated that both the Zn source and level did influence tibia strength and calcium (Ca) and Zn concentrations of tibia (P < 0.05), whereas there were no differences in the copper (Cu) and phosphorus (P) concentrations of the tibia and the tibia length (P > 0.05). Moreover, dietary supplementation with 40 or 80 mg/kg of organic Zn showed higher Zn and Ca concentrations in the tibia and higher tibia strength. The Cu concentration in the liver showed no difference among the 4 treatments, whereas the Zn concentration in the liver increased with the increasing Zn level. The apparent retention of P, iron (Fe), and manganese (Mn) was not affected by the Zn level or source (P > 0.05). However, the organic Zn group increased the apparent retention of Cu, Zn, Ca, crude protein (CP), and energy, and the group supplemented with 40 or 80 mg/kg of organic Zn obtained significant effects (P < 0.05). Moreover, dietary supplementation with 40 or 80 mg/kg organic Zn increased the MT mRNA expression of the liver at week 72, whereas 20 mg/kg of organic Zn decreased it (P < 0.05). In conclusion, this study suggested that an optimum dietary (40 mg/kg) organic Zn level plays a key role in promoting the apparent retention of minerals and nutrients, trace element deposit, and MT mRNA expression.

[Effect of a novel cold atmospheric plasma jet treatment with different temperatures on resin-dentin bonding]

OBJECTIVE

To investigate the effect of different treatment temperatures of a novel cold atmospheric plasma jet treatment on the resin-dentin bonding.

METHODS

(1) Fifty-two freshly extracted, non-carious and intact third molars were collected. The occlusal one-third of the crown was removed by means of a water-cooled low-speed Isomet saw. One dentin disc [(900 ±100) μm] was prepared for each tooth. The fifty-two dentin discs were randomly divided into control group and experimental groups, of which four were in control group, and forty-eight were divided into four experimental groups according to the different treatment temperatures (4 °C, 10 °C, 20 °C and 30 °C) of the novel radio-frequency atmospheric-pressure glow discharge (RF-APGD) plasma jet, twelve in each group. Each experimental group was divided into three subgroups according to different treatment time (10 s, 20 s and 30 s), with four in each subgroup. The occlusal one-third of the crown was removed by means of a water-cooled low-speed Isomet saw. The morphology of demineralized dentin surfaces was analyzed using field emission scanning electron microscopy. (2) Twenty unerupted, non-carious and intact third molars were randomly divided into five groups, four in each group: control group, untreated; 4 °C, 10 °C, 20 °C and 30 °C experimental groups, each group was treated with the RF-APGD plasma jet for 20 s. The micro-tensile resin dentin bond strength was tested after 20 s RF-APGD plasma jet treatment with different temperatures, using a universal mechanical machine.

RESULTS

(1) The field emission scanning electron microscopy results indicated that when compared with the control group, a 10 s RF-APGD plasma jet treatment with 30 °C and 20 °C collapsed the collagen scaffold. Collagen fibrils maintained an uncollapsed three-dimensional structure after the 4 °C RF-APGD plasma jet treatment for even 30 s treatment. (2) The microtensile resin dentin bond strength results of the 4 °C RF-APGD plasma jet treatment group (57.8±0.7) MPa were significantly higher than that of the control group [(47.4±0.5) MPa] and 10 s, 20 s and 30 s RF-APGD plasma treatment group [(51.9±0.7) MPa,(29.7±1.0) MPa and (22.2±1.5) MPa] with statistically significant difference (P<0.05). Compared with the control group, the micro-tensile bond strength increased about 21.9% and 9.5% after 4 °C and 10 °C RF-APGD plasma jet treatment, respectively.

CONCLUSION

Compared with other treatment temperatures, this novel RF-APGD plasma jet treatment with the temperature of 4 °C can preserve the three-dimensional morphology of demineralized dentin better, and can improve the resin-dentin bonding.

Abstract P3-03-01: Comparison of sentinel lymph node detection performances using methylene blue in conjunction with indocyanine green or radioisotope in breast cancer patients: A prospective single-center cohort study

Aim: This cohort study aimed to compare the clinical efficacies between the novel dual tracer composed of indocyanine green (ICG) and blue dye (BD) and the conventional dual tracer composed of radioisotope and BD for sentinel lymph node (SLN) mapping in breast cancer patients.

Methods: This study enrolled 471 clinically lymph node-negative patients with primary breast cancer. All the patients received mastectomy, while, for the sentinel lymph node biopsy (SLNB), they were randomized to receive BD plus radioisotope or BD plus ICG. Two hundred and twenty-seven patients received radioisotope plus BD (Control, RB group) for SLNB, while, 200 patients underwent the ICG plus BD (IB group) for SLNB. The detection performances on SLN identification rate, positive SLN counts, detection sensitivity, and false-negative rate were compared between the two groups. Following SLNB, axillary lymph node dissection (ALND) was performed only on patients with metastatic SLNs. Injection safety and potential side-effects of the two dual tracers were evaluated by a 24-month follow-up after the SLNB procedure.

Results: In the IB group, 97% (194/200) of the patients who underwent the ICG and BD dual tracer injection showed fluorescent-positive lymphatic vessels within 2-5 minutes. The identification rate of SLNs was comparable between the IB group (99.0%, 198/200) and the RB group (99.6%, 270/271) (P=0.79). No significant differences were observed in identification rate of metastatic SLNs (22.5% versus 22.9%, P&gt;0.05, RB group versus IB group, the same below), positive SLN counts (3.72±2.28 versus 3.91±2.13, P&gt;0.05), positive metastatic SLN counts (0.38±0.84 versus 0.34±0.78, P&gt;0.05), SLNB detection sensitivity (94.4% vs. 92.5%, P&gt;0.05), or false-negative rate (5.6% versus 7.5%, P&gt;0.05) between the two groups. No obvious allergic reaction or anaphylaxis, infection at the injection sites, skin necrosis or distal metastasis was reported in either group during the 24-month follow-up.

Conclusions: ICG can be used as a promising alternative tracer for radioisotope in SLN mapping, and when it is combined with BD in lymphangiography, it offers comparable detection sensitivity compared to the conventional lymphatic mapping strategies that are widely used in clinical practice.

Efficacy of indocyanine green vs. radioisotope + blue dye for sentinel lymph node mapping in breast cancer patients.Parameters99Tcm-Dx+BD(N=271)ICG+BD (N=200)P-valueSLN identification rate (%)99.6(270/271)99.0(198/200)0.79SLN counts3.91±2.133.72±2.280.09Metastatic SLN rate (%)22.9(62/271)25.5(51/200)0.51Metastatic SLN counts0.34±0.780.38±0.840.46Sensitivity92.5(62/67)94.4(51/54)0.96False-negative rate (%)7.5(5/67)5.6(3/54) 

Citation Format: Qi X, Yuan L, Zhang Y, Jiang J. Comparison of sentinel lymph node detection performances using methylene blue in conjunction with indocyanine green or radioisotope in breast cancer patients: A prospective single-center cohort study [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-03-01.

Clinical significance of angiopoietin-like protein 3 expression in patients with glioblastoma

There is strong evidence that angiopoietin-like peptide family is involved in the invasiveness and metastasis of cancer. Angiopoietin-like protein 3 (ANGPTL3) is proven to be involved in angiogenesis and tumor development. However, there is no published data on the role ANGPLT3 plays in glioblastomas. The present study was conducted to examine ANGPLT3 proteins expression and its association with clinicopathological factors and prognosis in human glioblastomas. Immunohistochemistry was used to evaluate the expression of ANGPTL3, EGFR and VEGFR. We found that 33 cases (57.9%) that showed strong immunostaining for ANGPTL3 proteins. However, there was no significant difference between the expression of ANGPTL3 and the proangiogenic factors, including EGFR or VEGFR. Patients with high/moderate expression of ANGPTL3 had a significantly shorter survival time (6.3 months) than those (median survival time 13.8 months) with low/negative expression. The overall survival (OS) was also investigated and analyzed by the Kaplan-Meier method, which showed a significant difference (P=0.0045, Breslow test). The present data leads to new insights into the role of ANGPTL3 in glioblastomas and provides an independent predictive factor.

Characterization of a hypervirulent fowl adenovirus 4 with the novel genotype newly prevalent in China and establishment of reproduction infection model of hydropericardium syndrome in chickens

Severe hydropericardium syndrome (HPS) has been present in layers in the northeast of China since June 2015, with mortality rates varying from 30 to 90%. Dead layers had severe hydropericardium with pericardial volumes of 5 to 20 mL, as well as inclusion body hepatitis. Laboratory investigations led to the isolation of a fowl adenovirus strain, HLJFAd15, from the liver tissue of dead layers. Natural deletions of ORF19 and ORF27 were found in this clinical strain by complete genome sequencing, which was identified with the novel genotype recently prevalent in China. The pathogenicity characterization was conducted in 35-day-old SPF chickens using HLJFAd15 with novel genotype of fowl adenovirus serotype 4 (FAdV-4). The reproduction disease cases of HPS with mortality rates of 76.9% by oral administration and 100% by intramuscular injection were induced successfully by challenging SPF chickens, respectively. Non-enveloped viral particles with a mean diameter of approximately 80 nm were found in the livers of virus-infected SPF chickens. Our study revealed that HLJFAd15 was identified with the novel genotype strains recently emerging in China by complete genome sequencing, and the strain was capable of causing HPS by the pathogenicity analysis. However, although there is currently no commercial vaccine against the novel genotype FAdV-4, the animal infection model established in this study was valuable for vaccine evaluation and development.

[Constituent and workload of service providers engaged in cancer screening: findings and suggestions from a multi-center survey in China]

Objective: To understand the constituent and workload of service providers engaged in cancer screening in China and provide evidence for the assessment of the sustainability of national cancer screening project. Methods: Using either questionnaire or online approach, the survey was conducted in 16 provinces, where Cancer Screening Program in Urban China (CanSPUC) was conducted, from 2014 to 2015. The medical institutes surveyed included hospitals [71.1% were class Ⅲ(A) hospitals], centers for disease control and prevention (CDCs) and community centers where cancer screening was undertaken during 2013-2015. The questionnaire survey was conducted among the staffs responsible for the overall coordination, management and implementation of the screening project to collect the information about the allocation, workload and compensation of the service providers from different specialties. Results: A total of 4 626 staffs were surveyed in this study, their average age was (37.7±9.5) years, and males accounted for 31.0%. Human resources allocated differed with province. The number of senior staff ranged from 6 (Chongqing) to 43 (Beijing) among the 8 comparable provinces. Among the staffs surveyed, 2 192 were from hospitals, 431 were from CDCs and 1 990 were from community centers, and the staffs who complained heavy workload accounted for 19.9%, 24.6% and 34.1% respectively (P<0.001). Among 227 staffs for overall coordination, 376 management staffs and 3 908 staffs for implementation, those who complained heavy workload accounted for 23.6%, 22.3% and 28.2% respectively (P<0.001). A total of 3 244 staffs (73.8%) got compensations for heavy workload. The compensation types were manly labor fee linked with workload (67.5%) and labor fee regardless workload (26.6%). Conclusion: The province specific differences in human resources allocation indicated the differences in screening project's organizing pattern and capability. It is suggested to conduct routine cancer screening (using specialized staffs), reduce the workload of the first line and community staffs and increase the compensation for the service providers for the sustainability of cancer screening project in China.

[Willingness of potential service suppliers to provide cancer screening in urban China]

Objective: Based on the investment for potential suppliers of cancer screening services, we assessed the reasons that affecting their participation motivation related to the long-term sustainability of cancer screening in China. Methods: Hospitals that had never been involved in any national level cancer screening project were selected by using the convenient sampling method within the 16 project cities of Cancer Screening Program in Urban China (CanSPUC) with 1 or 2 hospitals for each city. All the managers from the institutional/department level and professional staff working and providing screening services in these hospitals, were interviewed by paper-based questionnaire. SAS 9.4 was used for logical verification and data analysis. Results: A total of 31 hospitals (18 hospitals at the third level and, 13 hospitals at the second level) and 2 201 staff (508 hospital and clinic unit managers, 1 693 professional staff) completed the interview. All the hospitals guaranteed their potential capacity in service providing. 92.5% hospital managers showed strong willingness in providing cancer screening services, while 68.3% of them declared that the project fund-raising function was the responsibility of the government. For professional staff, their prospect gains from providing screening service would include development on professional skills (72.4%) and material rewards (46.8%). Their main worries would include extra work for CanSPUC might interfere their routine work (42.1%) plus inadequate compensation (41.8%). Medians of the prospect compensation for extra work ran between 20 to 90 Chinese Yuan per screening item respectively. For all the screening items, workers from the third-level hospitals expected their compensation to be twice as much of those working at the second level hospitals. Conclusion: Professional capacity building and feasible material incentive seemed to be the two key factors that influenced the sustainability and development of the programs.

Cardiac regeneration in Xenopus tropicalis and Xenopus laevis: discrepancies and problems

Two studies have recently focused on adult heart regeneration in Xenopus. While we reported on cardiac myogenic regeneration in Xenopus tropicalis after injury, Marshall and colleagues found no regeneration in an injured heart in Xenopus laevis. Here, we would like to join the discussion initiated by Marshall et al. who debated the methods and species differences in both studies. We agree with their view that the species difference in cardiac regenerative capacity could lead to different results in both of these studies. Moreover, we suggest that the age of the animals used in these studies could lead to differences in regeneration. A 5-year old X. laevis is much more advanced in age than a 1-year old X. tropicalis. The other reason for the discrepancies could be the size of the clot. Due to different resection protocols, the clot formed after the endoscopic resection performed by Marshall et al. was much larger than that after a conventional resection, as used in our study. Furthermore, the difference in the site of injury could influence the healing and regeneration differences. The influence of the organismal age, techniques used to induce injury and site of injury on regeneration need to be examined in detail to assess the regenerative potential of the amphibian heart.

Calhm2 governs astrocytic ATP releasing in the development of depression-like behaviors

Extracellular ATP is a widespread cell-to-cell signaling molecule in the brain, where it functions as a neuromodulator by activating glia and neurons. Although ATP exerts multiple effects on synaptic plasticity and neuro-glia interactions, as well as in mood disorders, the source and regulation of ATP release remain to be elaborated. Here, we define Calhm2 as an ATP-releasing channel protein based on in vitro and in vivo models. Conventional knockout and conditional astrocyte knockout of Calhm2 both lead to significantly reduced ATP concentrations, loss of hippocampal spine number, neural dysfunction and depression-like behaviors in mice, which can be significantly rescued by ATP replenishment. Our findings identify Calhm2 as a critical ATP-releasing channel that modulates neural activity and as a potential risk factor of depression.

C1QTNF3 in the murine ovary and its function in folliculogenesis

C1q/tumor necrosis factor-related protein 3 (C1QTNF3) is a novel adipokine with modulating effects on metabolism, inflammation and the cardiovascular system. C1QTNF3 expression levels in the sera and omental adipose tissues of women with PCOS are low compared to control subjects. However, the expression and function of C1QTNF3 in the ovary has not previously been examined. Here, we assessed the expression patterns of C1qtnf3 in the ovary and explored its role in folliculogenesis. The C1qtnf3 transcript abundance was higher in large follicles than in small follicles and was under the influence of gonadotropin. C1QTNF3 was detected mainly in the granulosa cells and oocytes of growing follicles and modestly in the granulosa cells of atretic follicles and in luteal cells. Excess androgen significantly decreased C1QTNF3 expression in the ovaries in vivo and in granulosa cells in vitro. Recombinant C1QTNF3 protein accelerated the weight gain of ovarian explants and the growth of preantral follicles induced by follicle stimulating hormone (FSH) in vitro. The stimulatory effect of C1QTNF3 on ovarian growth was accompanied by the initiation of AKT, mTOR, p70S6K and 4EBP1 phosphorylation, an increase in CCND2 expression and a reduction in cleaved CASP3 levels. Moreover, the addition of C1QTNF3 accelerated proliferation and reduced activated CASP3/7 activity in granulosa cells. In vivo, the ovarian intrabursal administration of the C1QTNF3 antibody delayed gonadotropin-induced antral follicle development. Taken together, our data demonstrate that C1QTNF3 is an intraovarian factor that promotes follicle growth by accelerating proliferation, decelerating apoptosis and promoting AKT/mTOR phosphorylation.

Variations of blood glucose in cancer patients during chemotherapy

PURPOSE

The aim of this study was to analyze the blood glucose (BG) variations in cancer patients during chemotherapy according to tumor types and chemotherapeutic regimens.

MATERIALS AND METHODS

Patients were examined from the Department of Medical Oncology of Cancer Hospital and Institute, Chinese Academy Medical Sciences from January 2012 to December 2014. The patients' ages, genders, body mass index, associated disease history, and corresponding BG values were recorded.

RESULTS

Among these 2029 patients, 331 (16.3%) patients encountered high BG during chemotherapy except diabetic patients. Of these patients, 208 (62.8%) were males, and 123 (37.2%) were females, with age ranged from 17 to 84 years. The 331 cases included 23 tumor types and 77 regimens. Totally, BG values increased up to 7.4 ± 1.3 mmol/L during chemotherapy.

CONCLUSIONS

No previous studies in the literature have examined systematically so numerous cases of hyperglycemia during chemotherapy. This study has pointed out possible high-risk chemotherapeutic regimens and tumor types, which should be paid attention to prevent the occurrence of hyperglycemia.

[Potential demand on cancer screening service in urban populations in China: a cross-sectional survey]

Objective: To understand the acceptance and personal demand for cancer screening service among the urban residents who had never been involved in any national level cancer screening programs in China and identify the key factors influencing the sustainability of cancer screening. Methods: A questionnaire survey was conducted among the local people aged 40-69 years selected through convenience sampling in 16 provinces of China to collect the general information about their demands for the screening service and others. Results: A total of 16 394 qualified questionnaires were completed. The average age of the people surveyed was (53.8±8.0) years, and men accounted for 44.6%. Without concerning the cost, 4 831 people (29.5%) had no demands for cancer screening services, the reasons are as follow: they would like to go to see doctors only when they were ill (61.8%); they had already received similar medical examinations (36.8%) and they would like to receive cancer screening directly without pre-health risk assessment (33.0%). Among the people surveyed, 10 795 (65.8%) had demands for cancer screening services, but they had choice on the screening settings, 43.7% wanted to receive the service in a general hospitals, while 36.5% would like to go to cancer-specialized hospitals. As for the level of medical institutes providing cancer screening service, 61.4% of the people surveyed would choose a higher level one, while 36.4% would choose an ordinary one. On screening procedures, 61.5% of the people surveyed would accept the mode of "clinical examination after questionnaire-assessment" . Conclusion: Most people surveyed had demands for cancer screening services and they would like to receive the screening services in higher level medical institutes. It is suggested to spread cancer screening know ledge, and strengthen the capability building of screening in grass root medical institutes to attract more people to receive cancer screening.

[Preference on screening frequency and willingness-to-pay for multiple-cancer packaging screening programs in urban populations in China]

Objective: From an actual cancer screening service demanders' perspective, we tried to understand the preference on screening frequency and willingness-to-pay for the packaging screening program on common cancers and to evaluate its long-term sustainability in urban populations in China. Methods: From 2012 to 2014, a multi-center cross-sectional survey was conducted among the actual screening participants from 13 provinces covered by the Cancer Screening Program in Urban China (CanSPUC). By face-to-face interview, information regarding to preference to screening frequency, willingness-to-pay for packaging screening program, maximum amount on payment and related reasons for unwillingness were investigated. Results: A total of 31 029 participants were included in this survey, with an average age as (55.2±7.5) years and median annual income per family as 25 000 Chinese Yuan. People's preference to screening frequency varied under different assumptions ( " totally free" and "self-paid" ). When the packaging screening was assumed totally free, 93.9% of residents would prefer to take the screening program every 1 to 3 years. However, the corresponding proportion dropped to 67.3% when assuming a self-paid pattern. 76.7% of the participants had the willingness-to-pay for the packaging screening, but only 11.2% of them would like to pay more than 500 Chinese Yuan (the expenditure of the particular packaging screening were about 1 500 Chinese Yuan). The remaining 23.3% of residents showed no willingness-to-pay, and the main reasons were unaffordable expenditure (71.7%) and feeling'no need'(40.4%). Conclusions: People who participated in the CanSPUC program generally tended to choose high-frequency packaging screening program, indicating the high potential acceptance for scale-up packaging screening, while it needs cautious assessments and rational guidance to the public. Although about seven in ten of the residents were willing to pay, the payment amount was limited, revealing the necessity of strengthening individual's awareness of his or her key role in health self-management, and a reasonable payment proportion should be considered when establishing co-compensation mechanism.

[Willingness and preferences of actual service suppliers regarding cancer screening programs: a multi-center survey in urban China]

Objective: From the perspective of actual service suppliers regarding cancer screening, this study aimed to assess the long-term sustainability of cancer screening programs in China. Methods: Based on a Cancer Screening Program in Urban China (CanSPUC), our survey focused on all the hospitals, centers for disease control and prevention (CDC) and community service centers across 16 provinces in China which participated in the programs between 2013 and 2015. All the managers (institutional/department level) and professional staff involved in the program were interviewed using either paper-based questionnaire or online approach. Results: A total of 4 626 participants completed the interview. It showed that the main gains from providing screening service emphasized promotion in social value (63.6%), local reputation (35.9%), and professional skills (30.6%), whereas difficulties encountered included inadequate compensation (30.9%) and discordance among information systems (28.3%). When the service remuneration amounts to about 50 Chinese Yuan per screening item, those professional staff self-reported that they would like to work overtime. More than half (63.7%) of the staff expressed willingness to provide routine screening service, the main expectations were to promote their reputation to the local residents (48.7%) and to promote professional skills (43.1%). Those who were not willing to provide screening services were worried about the potential heavy workload (59.8%) or being interfered with their routine work (49.8%). Further detailed results regarding the different organization types and program roles were presented in the following detailed report. Conclusions: Findings of gains and difficulties showed that if cancer screening is expected to become a long-term running, incentive mechanism from the program, external promotion and advocacy as well as capacity building should be strengthened; furthermore, rewards to staff's screening services should be raised according to the local situations. Results regarding the "willingness to provide service" showed that management of the program should also be strengthened, including information system building and inter-agency and inter-department coordination at the government levels.

General-purpose readout electronics for white neutron source at China Spallation Neutron Source

The under-construction White Neutron Source (WNS) at China Spallation Neutron Source is a facility for accurate measurements of neutron-induced cross section. Seven spectrometers are planned at WNS. As the physical objectives of each spectrometer are different, the requirements for readout electronics are not the same. In order to simplify the development of the readout electronics, this paper presents a general method for detector signal readout. This method has advantages of expansibility and flexibility, which makes it adaptable to most detectors at WNS. In the WNS general-purpose readout electronics, signals from any kinds of detectors are conditioned by a dedicated signal conditioning module corresponding to this detector, and then digitized by a common waveform digitizer with high speed and high precision (1 GSPS at 12-bit) to obtain the full waveform data. The waveform digitizer uses a field programmable gate array chip to process the data stream and trigger information in real time. PXI Express platform is used to support the functionalities of data readout, clock distribution, and trigger information exchange between digitizers and trigger modules. Test results show that the performance of the WNS general-purpose readout electronics can meet the requirements of the WNS spectrometers.

Heart regeneration in adult Xenopus tropicalis after apical resection

Background

Myocardium regeneration in adult mammals is very limited, but has enormous therapeutic potentials. However, we are far from complete understanding the cellular and molecular mechanisms by which heart tissue can regenerate. The full functional ability of amphibians to regenerate makes them powerful animal models for elucidating how damaged mature organs are naturally reconstituted in an adult organism. Like other amphibians, such as newts and axolotls, adult Xenopus displays high regenerative capacity such as retina. So far, whether the adult frog heart processes regenerative capacity after injury has not been well delineated.

Results

We examined the regeneration of adult cardiac tissues of Xenopus tropicalis after resection of heart apex. We showed, for the first time, that the adult X. tropicalis heart can regenerate perfectly in a nearly scar-free manner approximately 30 days after injury via apical resection. We observed that the injured heart was sealed through coagulation immediately after resection, which was followed by transient fibrous tissue production. Finally, the amputated area was regenerated by cardiomyocytes. During the regeneration process, the cardiomyocytes in the border area of the myocardium adjacent to the wound exhibited high proliferation after injury, thus contribute the newly formed heart tissue.

Conclusions

Establishing a cardiac regeneration model in adult X. tropicalis provides a powerful tool for recapitulating a perfect regeneration phenomenon and elucidating the underlying molecular mechanisms of cardiac regeneration in an adult heart, and findings from this model may be applicable in mammals.

Electronic supplementary material

The online version of this article (10.1186/s13578-017-0199-6) contains supplementary material, which is available to authorized users.