Aim: This study examined the neurodevelopment trajectories, the prevalence of delays, and the risks and protective factors  associated with cognitive, motor, and language development for preterm infants from 4– to 24-months.Method: We assessed 186 preterm infants  from 4– to 24-months using the Bayley Scales of Infant Development – III. Maternal practices and knowledge were assessed using the Daily Activities of Infant Scale and the Knowledge of Infant Development Inventory. Birth risks and adverse outcomes were obtained from infant medical profiles.Results: A high prevalence of delays was found; red flags for delays at 24-months were detected at 4– and 8-months of age. The neurodevelopmental trajectories showed steady scores across time for cognitive composite scores for extremely- and very-preterm infants and for language composite scores for the extremely- and moderate/late-preterm; a similar trend was observed for the motor trajectories of moderate/late preterm. Changes over time were restricted to motor composite scores for extremely- and very-preterm infants and for cognitive composite scores for moderate/late preterm; declines, stabilization, and improvements were observed longitudinally. Positive, strong, and significant correlations were for the neurodevelopment scores at the first year of life and later neurodevelopment at 18 and 24 months. The cognitive, language, and motor composite scores of extremely and very preterm groups were associated with more risk factors . However, for moderate/late preterm infants, only APGAR and maternal practices significantly explained the variance in neurodevelopment.Discussion: Although adverse outcomes were strongly associated with infant neurodevelopment, the environment and the parents’ engagement in play and breastfeeding were protective factors for most preterm infants. Intervention strategies for preterm infants should start at 4– to 8-months of age to prevent unwanted outcomes later in life. Annually worldwide, about 30 million infants are born premature . In BrazSeveral risk factors negatively affect preterm infants. Adverse outcomes, such as cerebral injuries , leukomaAlthough prenatal care services have advanced in recent years, the early diagnosis of preterm infants who have adverse outcomes  and the This study aimed to examine, longitudinally, the neurodevelopment trajectories (changes and stabilization of composite scores), the prevalence of delays, and the risks and protective factors  associated with cognitive, motor, and language development for extremely, very, and moderate/late preterm infants from 4– to 24-months of corrected age (CA). We expected that the extreme and the very preterm infants would have a significantly lower neurodevelopment rate, higher prevalence of delays, and more risk factors associated with those outcomes. Moderate/late preterm infants will also develop unsteadily over time; however, they would have less prevalence of delays and fewer risk factors associated with the outcomes. Also, we expect that protective factors would be associated with better developmental scores in all groups.N = 242) from a cohort longitudinal study in a public hospital in Brazil were initially enrolled in the present study. The assessments were carried out from July 2016 to December 2019. The hospital ethical review board approved the research, and parents signed informed consent. Data from the preterm infants who attended at least two longitudinal assessments were analyzed . All infants had several adverse outcomes and environmental risk factors that imply a high risk of disability. The extremely and very preterm groups stayed for long time in NICU , needed mechanical ventilation , parenteral nutrition (>90%), and blood transfusion . Extremely (43.5%) and very (23.6%) preterm infants had combined early sepsis, later sepsis, and PIVH. Most infants were from low-income families .Preterm infants  , adoptinThe sample size calculation was performed based on the results of the composite scores of the Bayley-III scales throughout the follow-up, using the WinPEPI program (Programs for Epidemiologists for Windows), version 11.43. Considering a significance level of 5%, power of 80%, and a minimum effect size of 0.6 standard deviations between the assessments, a minimum total of 24 children per group was obtained .T-test and ANOVA with Tukey post hoc were used to compare groups’ means, and in the case of asymmetries, the Kruskal–Wallis and Dunn in the case of asymmetric distribution were used as a post hoc. The Chi2 was used to compare groups for categorical variables with the residual test as a post hoc. Pearson or Spearman correlations were used to verify associations between quantitative variables. For the Pearson and Spearman correlations recognizes cut off were used .Regarding risk and protective factors, several measures were used to compare groups. The GEE  model with the Least Significant Difference adjustment was conducted to compare BSID-III scores for intra- and inter-groups longitudinally. The linear model (symmetric distribution), the gamma model (asymmetric distribution), or the logistic model  were adopted. The logistic model in the GEE was used to compare the frequencies of delays. The GEE was used to examine the longitudinal data since it involves repeated measurements of cognitive, language, and motor scores that tend to correlate with one another, which must be taken into proper account. The GEE models allow for substantial flexibility in specifying the correlation structure within cases and offer the potential for valuable substantive insights into the nature of that correlation . The GEEN = 46; very preterm N = 101; and moderate/late preterm N = 38). The scores used in the multivariate regression analysis were the ones obtained in the last assessment of each infant; 47% (n = 71) of all infants had their last assessment at 24 months, 30% (n = 45) of them at 18 months, and 23% (n = 36) of them at 12 months; the extraction method was used in the regression model to control for confounding factors. The criterion for entering the variable in the multivariate model was a p-value < 0.20 in the bivariate analysis. The criterion for maintaining the variable in the final model was a p-value < 0.10 in the multivariate analysis, following recognized guidelines for Backward regression .Backward multivariate linear regression was used to examine the risks and protective factors (exposure variables) associated with infants’ outcomes  by groups , socioeconomic factors  and Bayley scores at all ages, 4 months , 8 months , 12 months , 18 month  and at 24 months . These results support the GEE robustness even with missing data.In the present study we assume that the data is missing at random, as some children have assessments at two, three, four, or five time points randomly. Nevertheless, group comparisons were conducted with all variables between the two groups . Similarity was observed between groups for birth factors and adverse outcomes  and language (p = 0.106) composite scores. A significant group-by-time interaction was found for motor composite scores (p = 0.004). Higher scores were found for extremely preterm compared to the very preterm at 4-months (p = 0.013), and at 12-months (p = 0.007), the extremely preterm showed lower composite scores compared to moderate/late preterm. The GEE analysis showed non-significant interactions for groups by time for cognitive ; group effect was found at 12-months with a higher prevalence of delays for the extremely preterm group than in the very preterm (p = 0.035). Regarding language, a non-significant group by time interaction was found (p = 0.106); group effect was significant at 8-months with a higher prevalence of delays in the extremely preterm group than in the very preterm (p = 0.029). Regarding motor delays prevalence, a significant group by time interaction was found (p = 0.004). A higher prevalence of motor delays was found for the very preterm infants compared to the extremely preterm at 4-months (p = 0.013); however, at 12-months a higher prevalence of motor delays was found in the extremely preterm group than in the moderate/late preterm infants (p = 0.007). Increases in the prevalence of motor delays in the extremely preterm infants from 4– to 12-months (p < 0.001) were also found.M = 78.7; SD = 22.1; p = 0.002) and cognitive  development compared to infants without PIVH. Infants with NICU seizures had significant lower composite scores for motor , cognitive , and language  development compared to infants without NICU seizures. For the very preterm group, infants with PIVH had similar neurodevelopment scores to those without PIVH, and infants with NICU seizures had significant lower composite scores for motor , cognitive , and language  development compared to those without NICU seizures. Moderate/late preterm group, infants with PIVH or NICU seizures had similar neurodevelopment scores to those without PIVH or NICU seizures.Correlations results for birth factors, adverse outcomes, environmental risks, maternal practices, and maternal knowledge with cognitive, language, and motor scores by groups are presented in All assumptions for the multivariate regression model were met. Appropriate values of skewness and kurtosis (Sk ≤ 2.0 and Ku ≤ 3.8), the residuals of the regression were normality distributed, and the results of variance inflation factor clear suggested no multicollinearity in the data . Therefore, the backward multivariate regression was conducted. The regression analysis showed different predictors for each group. For the extremely preterm group, 43.9% of the variance in cognitive development was explained by the PIVH and NICU seizures, 20.6% of the variance in language by the formal maternal education and NICU seizures, and 78.8% of the variance in the motor by active play, NICU seizures, Apgar, formal maternal education, and the number of children at home. All variables were significant predictors of neurodevelopment (Beta from 0.27 to 0.54), and all with moderate and large effect size.For the very preterm group, 36.3% of the variance in cognitive development was explained by NICU stay, breastfeeding, maternal education, 27.9% of the variance in language by the number of prenatal care visits, maternal education, and NICU seizures, 47.1% of the variance in the motor by active play, parents living together, oxygen therapy, and maternal education. Some variables fail to remain significant in the model, but several predictors were found .For the moderate/late premature group, fewer variables explained the model variance; 21.3% of the cognitive development was explained by the Apgar 5th minute, and 28.3% and 32.3% of the language and motor development variance, respectively, were explained by breastfeeding. All factors significantly predict neurodevelopment . Infant neurodevelopment at 8-months had a similar pattern that was observed again at 24-months. Like our results, a previous study showed that a considerable rate of extremely preterm infants scored below 70 in cognitive, language, and motor development at 2-year-old ; and anoA similar pattern of delays was found for the overall development at 4– and 24-months of age. Lower prevalence of delays has been reported for very preterm infants at 18-months   and at 2A higher prevalence of delays for the cognitive, language, and motor outcomes was found at 8-months, compared to the other ages. Less is known about moderate/late preterm regarding development, limiting our capacity to contrast results. However, cognitive impairments have been reported before the age of 3-years , and minFor the three preterm group, a closer look at development trajectories (measured by the composite scores), the prevalence of overall delays , and the correlations within each domain and age suggested that infant performance at the first year of life, at 8-months, had a similar pattern that was observed again at 24-months, strong associations were found between age and infant performance.Overall, extremely preterm infants had a higher prevalence of cognitive and motor (12-months) and language (8-months) delays, and for this group, the prevalence of delays significantly increased from 4– to 12-months. The prevalence of developmental delay is inversely proportional to gestational age and birth weight , and it It is essential to notice that, although prematurity is an independent risk factor for developmental adversities, the population of preterm infants shows considerable variability in the severity of their impairments , and it Different adverse outcomes were associated and were accounted for the variability in neurodevelopment. For extremely, very, and moderate/late preterm groups, the predictors were PIVH, NICU seizures and stay, and Apgar 5th minute.Periventricular hemorrhage was a strong predictor for cognitive development in the extremely preterm group, similar to previous studies . ModeratDuring hospitalization, seizures were also a predictor of cognitive, language, and motor development for extremely preterm infants. Neonatal seizures have been reported as significantly related to low motor scores; 23.1% of children who suffered a seizure had a delay in acquiring motor skills , similarProlonged hospitalization, a consequence of several adverse outcomes, was inverse and significantly associated with very preterm cognitive development. Previous studies showed a similar trend; the longer the hospitalization, the more unfavorable outcomes in the cognitive development were found for preterm infants . HospitaApgar score in the 5th minute of life was predictive of motor development in the extremely preterm group and cognitive development in the moderate/late preterm group. Previous association for mental and gross motor development  has beenThe environmental factors, maternal education, number of children at home, number of prenatal care visits, and parents living together were associated and accounted for the variability in the neurodevelopment of extremely and very preterm groups.Maternal formal education was a significant predictor of language development for the extremely and very preterm groups, like previous studies , and motThe parents’ stable union and a shared life in the same house was a predictor for motor development of the very preterm group, a plausible explanation for this finding is a higher motor stimulation quality within environments where both parents live together . Being cThe number of prenatal care visits was a strong predictor for language development in the very preterm group. Previous studies have reported that the lack of prenatal care was associated with deficits in motor development , physicaIt is essential to notice that the environmental risk factors could change and affect neurodevelopmental outcomes differently depending on the child’s age. The present study measured its effect on neurodevelopment across the second year of life, from 12 to 24 months, with no distinction of a specific period. Therefore, the results can only be interpreted for this age span.n = 71) of all infants had their last assessment at 24 months, 30% (n = 45) of them at 18 months, and 23% (n = 36) of them at 12 months; the extraction method was used in the regression model to control for confounding factors.The scores used in the multivariate regression analysis were the ones obtained in the last assessment of each infant; 47%  have also been related to maternal education . These tBreastfeeding was the second most reliable predictor of cognitive development for the very preterm group and the strongest and only predictor for language and motor development of moderate/late preterm groups. The longer the breastfeeding duration, the higher the cognitive, language, and motor development of those infants. Breastfeeding has been long recognized as a predictor of cognitive, language, and motor development , similarOur results lead us to acknowledge the specific risk and protective factors associated with neurodevelopment outcomes in the different levels of prematurity, an expected result in this preterm population. As presented in the results, the lower the gestational age, the greater were the associations with biological risk factors. On the contrary, as gestational age increases, environmental factors become more relevant. Extremely infants are usually more affected by severe clinical conditions, requiring several interventions during the NICU stay. Thus, the birth risks and clinical adversity overlap with environmental factors; even if the environment positively affects their neurodevelopment, the established disadvantages are possibly enduring in the neurodevelopment’s harmful effect. Nevertheless, maternal education plays an influential protective role in language and motor development and plays with the infant in motor development, even in this unfavorable condition. As the gestational age increases, we observed that for very preterm, the environment gain intensity in protecting infant cognitive development – maternal education was a protective factor for overall neurodevelopment and play with infant remains a strong positive influence in motor development. Regarding the moderate/late preterm, infants have milder clinical conditions, fewer risk factors were associated with the outcomes, as hypothesized, and protective factors – prolonged breastfeeding positively impact language and motor development.The strengths of this study lie in examining neurodevelopmental trajectories in the extremely, very, and moderate/late preterm infants from an LMIC (Low-Moderate Income Countries); longitudinal data for preterm infants from LMIC still feeble. One other strength concerns the fact that we have examined not only risk factors but several environmental factors ; those factors are still under-examined in several countries, from high- to low-income economics, due to its complexity. Therefore, it is the first longitudinal study to show that some features combined of the infants’ early rearing in the home, such as parents’ engagement in play and breastfeeding, were protective factors for the neurodevelopment of preterm infants with several adverse outcomes in LMIC. Another strength is to provide evidence that the infant’s neurodevelopment observed in the first year of life, particularly at 8 months, was highly associated with the infant neurodevelopment at 18 and 24 months. The results suggest the observation of red flags early in life for extremely-, very-, and moderate/late- preterm infants from LMIC.One weakness concerns the fact that we faced a common difficulty when carrying out longitudinal studies. The missing subjects throughout the longitudinal assessments and consequence uneven distribution of the groups were limitations of the present study. Overall missing data were due to the family’s mobility to other cities to find better job opportunities, parental withdrawal from the follow-up clinic, and mothers joining the workforce. The missing data restrict our capability to examine the environmental factor effect at each specific age , and environmental factors could affect children neurodevelopmental differently across this age. Therefore, our recommendation for future studies is to assess environmental factors at specific ages to understand their impact on child life deeply. Also, our results can only be translated to similar LMIC populations with the social strata representation, and our results need further replication.Another limitation is related to the study design. We conducted a cohort study with three preterm groups; however, the lack of at-term infants’ group restraints our capability to compare the preterm group’s developmental trajectories with at-term infants. Therefore, we were unable to obtain information related to the exact age that preterm infants’ trajectories become different from at term and fall behind.The developmental trajectories of the very preterm infants in our study indicated that the delays observed at 2 years old in cognitive, language, and motor development were observable early (at 4– and 8-months), suggesting that the red flags for delays in preterm infants’ neurodevelopment could be detected very early. This study reinforces the importance of early detection and long-term follow-up of preterm infants. The results support the use of BSID-III to assess preterm infants at 4– and 8-month-old in follow-up clinics to prevent undesirable outcomes. At this age, several milestones are observed , and the referral to intervention programs could lessen or prevent the undesirable outcomes at 24-months. Specifically, from our results, interventions to provide parental support to maintain exclusive breastfeeding for the first six months of life and training parents to implement a daily routine of active play with the child, with age-appropriate activities, would benefit infants and their families. Early intervention will increase the likelihood of change in motor trajectories and may inhibit the emergence of possible impairments. Cognitive, language, and motor delays observed in the present study at 24-months will likely contribute to further developmental challenges; therefore, our recommendation is the follow-up of preterm infants until preschool age.Besides the early detection of delays in this heterogeneous population, it is essential to understand better the determinants of infant exposure to many risk factors and the protective factors supporting preterm infants born at different gestational ages. Consequently, our results support the need to investigate the risk and protective factors in specific preterm groups  in different periods of life. Although adverse outcomes were strong predictors of neurodevelopment in extremely and very preterm infants, environment variables  and maternal practices (active play) were protective factors that positively influenced the infants’ neurodevelopment trajectory. A similar trend was observed for moderate/late preterm infants regarding breastfeeding, a single protective factor to overall infant development. Therefore, although the adverse outcomes are risks inherent to the preterm populations, programs focused on maternal training could improve the stimulation and quality of opportunities at home for preterm infants and prevent further risks. Advances in access to information regarding infant development and quality of daily care should focus on public policies in developing countries with high prematurity rates.The original contributions presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author/s.The studies involving human participants were reviewed and approved by Comitê de Ética do Hospital de Clínicas de Porto Alegre – Universidade Federal do Rio Grande do Sul. Written informed consent to participate in this study was provided by the participants’ legal guardian/next of kin.NV, LB, and CP contributed to study design, data acquisition and interpretation, and manuscript preparation. NV, BS, RP, and RS contributed equally to manuscript revision, providing significant oversight on the intellectual content. All authors critically reviewed the manuscript and approved the version submitted for publication.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


These were compared to the broiler alternative from the European Surveillance of Veterinary Antimicrobial Consumption (DDDvet), that mention DDDvet as a proxy for other poultry species. DDDturkey ranged from being 81.5% smaller to 48.5% larger compared to its DDDvet alternative for broilers. Second, antimicrobial treatments were registered on 60 turkey farms divided over France, Germany and Spain between 2014 and 2016 (20 flocks per country). Afterwards, AMU was quantified using treatment incidence (TI) per 100 days. TI expresses the percentage of the rearing period that the turkeys were treated with a standard dose of antimicrobials. Minimum, median and maximum TI at flock level and based on DDDturkey = 0.0, 10.0 and 65.7, respectively. Yet, a huge variation in amounts of antimicrobials used at flock level was observed, both within and between countries. Seven farms (12%) did not use any antimicrobials. Aminopenicillins, polymyxins, and fluoroquinolones were responsible for 72.2% of total AMU. The proportion of treating farms peaked on week five of the production cycle (41.7%), and 79.4% of the total AMU was administered in the first half of production. To conclude, not all DDDvet values for broilers can be applied to turkeys. Additionally, the results of AMU show potential for reducing and improving AMU on turkey farms, especially concerning the usage of critically important antimicrobials.Antimicrobial resistance (AMR) threatens our public health and is mainly driven by antimicrobial usage (AMU). For this reason the World Health Organization calls for detailed monitoring of AMU over all animal sectors involved. Therefore, we aimed to quantify AMU on turkey farms. First, turkey-specific Defined Daily Dose (DDD Many components of our human and animal healthcare depend on the availability of effective antimicrobials. Thanks to these antimicrobial drugs, bacterial infections have become far less life threatening . HoweverIn Veterinary Medicine, the first international report on AMU in Europe was published in 2010 by the European Surveillance for Veterinary Antimicrobial Consumption (ESVAC), which is part of the European Medicines Agency (EMA). Back then, this report included sales data in tonnes of active substance (AS) from 9 European countries for the period between 2005 and 2009 . The ESVvet) and Defined Course Doses (DCDvet) for animals. Yet again, the focus was, understandably, put on the major food production animals with DDDvet and DCDvet values for pigs, cattle and broilers. ESVAC does mention that the latter can be used as a proxy for other poultry species . Th. Thturketurkey and DCDturkey, this study also quantified AMU in 20 French, 20 German and 20 Spanish turkey farms. As far as the authors are aware, this is the first multi-country study reporting on AMU in turkeys at farm level, allowing for comparison of AMU between farms, both within and between countries. Four other studies did look into AMU in turkey production [In addition to the establishment and description of DDDoduction ,16,17,33oduction ,16 used vet for broilers could be used as a proxy for DDDturkey to quantify AMU on turkey farms. However, noticeable differences were present between the results from TIDDDvet-FL and TIDDDturkey-FL. For example, TIDDDvet-FL of the highest using farm from country H was 14% lower than its TIDDDturkey-FL. This can be explained by the amoxicillin (n = 4) and colistin (n = 4) treatments on that farm, that have a DDDturkey that is 11.9% and 33.3% lower than its corresponding DDDvet, respectively  and DCD, both at treatment and flock level , which aectively . On avervet (95% CI) = 9.0 (5.5–10.8)) [turkey (95% CI) = 10.0 (8.0–11.9)). On one hand, other studies confirm this and report a four times higher [TI results show big variation in AMU between the flocks, both within and between countries. All countries had at least one flock that did not receive any antimicrobial treatments, while other flocks stood out due to higher usage. This shows potential for reducing AMU on turkey farms. Both an Italian 2015–2017) and Austrian (2013–2019) study already reported on the reduction of AMU in turkeys ,17. When and Aust5–10.8)) , AMU in s higher , 2.4 tims higher , 2 timess higher  and 1.7 s higher  and an As higher ,37,38,39Three antimicrobial classes represented 72.2% of all registered AMU in this study. Similar results were discussed by ESVAC  and in sTreatments administered in the first nine weeks represent the majority (79.4%) of all AMU registered in this study. Previous studies in other intensive livestock production systems, such as pigs  and broiAll data were collected within the EU-FP7 EFFORT project. This project studied the epidemiology and ecology of AMR in food-producing animals, the environment and humans, to quantify AMR exposure pathways for humans.In July 2017, all antimicrobial products registered for use in turkeys in France, Germany and Spain were listed. This information was obtained from official online databases managed by the national regulatory institutions involved in the authorization and registration of veterinary medicinal products. In France this online database is the Index des Médicaments Vétérinaires Autorisés en France (IRCP) ; in GermA DDD, expressed in mg/kg body weight per day, was calculated for each authorized product based on the mean recommended dose from the country-specific SPC. When a recommended dose was given as a range, the lower value was seen as the minimal recommended dose and the higher value was seen as the maximal recommended dose. Based on these two values, a mean recommended dose was calculated. When an AS was expressed in international units (IU) in the SPC, the recommended dose was recalculated to mg/kg based on the conversion factors published by ESVAC . When thturkey and DCDturkey values is derived from a study by Postma and colleagues [turkey. This was also done at country level to result in DDDturkey-National, in this case each country has its own DDDturkey values for each unique combination of ASs and administration route. Similar to the DDDturkey calculations, DCD values were used to become DCDturkey for each unique combination of ASs and administration route. Finally, differences between the mean recommended dose of the individual products and their corresponding DDDturkey value were evaluated. In addition, differences were also observed between, on one hand the DDDturkey and DCDturkey values, and on the other hand their corresponding DDDvet and DCDvet values for broilers, as calculated by ESVAC [turkey and DCDturkey values were only calculated for active substances that were used on the 60 participating farms in this study.The methodology used for the calculation of DDDlleagues  and the lleagues . Each prby ESVAC . DDDturkIn a cross-sectional study, AMU data was collected at 20 turkey farms in each of the participating countries: France, Germany and Spain between October 2014 and October 2016. The selection of farms was subject to inclusion criteria to obtain a homogenous group of farms, both within as between countries. All farms were conventional farms with an all-in-all-out system and had to have at least 3000 birds. Farms had to be epidemiologically unrelated to one another, meaning they could not have contact through trade and each farm had only one owner. Farms were selected in agreement with local farming organizations. Wherever possible, regional stratification was implemented. However, this only succeeded in Germany, while farms in France and Spain were concentrated in the region of Brittany and Andalusia, respectively, the main turkey production sites of these countries. As the 20 farms in each country cannot be considered representative for the turkey production in a country, countries were anonymized . On each farm researchers filled in a questionnaire with the farmers to collect technical and AMU data from the farm. To reduce interview bias, researchers followed a questionnaire protocol and received a training. Additionally, information regarding each antimicrobial treatment given to the sampled flock (1 house) was registered. These data are referred to as treatment data and covered all antimicrobial group treatments given to the flock from set-up to slaughter. The indication for each treatment was also registered and was based on the expertise of the veterinarian or farmer. Diagnostics could have been used but were not mandatory. More information and relevant parts of the questionnaire can be found in the turkey, DCDturkey, DDDvet, DCDvet and UDD) resulting in five different formulas . However, the basic structure of each formula remains the same, as shown in turkey/DDDvet expresses the number of DDDturkey or DDDvet that were administered per 100 animal-days at risk. In other words, TI equals the number of days per 100 animal-days that the flock has received a standard dose of antimicrobials. Simplified, it reflects the percentage of time that a turkey has been treated with antimicrobials in its life. Secondly, TIDCDturkey/DCDvet reflects the number of treatment courses, based on DCDturkey or on DCDvet, per 100 animal-days at risk. Finally, the formula for TIUDD is a simplified version of TIDDDturkey as here UDD appears both in the nominator and denominator. However, the meaning is the same, only here it represents the number of UDD instead of DDD that were administered per 100 animal-days at risk. To calculate a TI at flock level, TIs of all treatments from one flock were added up to obtain TIDDDturkey-FL, TIDCDturkey-FL, TIDDDvet-FL, TIDCDvet-FL.AMU was quantified following the same methodology as described by Joosten et al. . The latturkey, DCDturkey, DDDvet and DCDvet are shown in vet and DCDvet values for broilers are defined by ESVAC and can be used as a proxy for other poultry species [turkey and DCDturkey have been described above .Processing of the AMU data was done following the protocol from the EFFORT project as described in previous publications ,40. Dataturkey and DCDturkey to allow for a species-specific, on farm quantification of AMU on European turkey farms. Assigning DDDturkey has shown the need for a unified European antimicrobial drug portfolio and harmonization of recommended doses across the SPCs of similar antimicrobial products authorized for use in turkeys, at the least when treating identical diseases. The overview provided in this study can help guide prioritisation and selection of candidates. Additionally, a comparison with DDDvet values from ESVAC, shows that not all DDDvet values for broilers can be applied to turkeys. Therefore, preferably DDDturkey is used when quantifying AMU on European turkey farms. Furthermore, AMU on turkey farms showed great variation regarding the amount used. The majority of the antimicrobials were used in the beginning of production and very often CIAs were used. This shows potential for reducing and improving AMU on turkey farms.This study presents a list of DDD


Nurses are at high risk of psychological distress including stress, depression, and anxiety due to low personnel density and high work demand. Despite mounting evidence showing that role stress is a risk factor for nurses' psychological distress, the mediating and moderating mechanisms underlying this relationship are less known. This study tests the mediation effect of burnout in the association between role stress and psychological distress, and whether this mediation is moderated by social support.A sample of 623 Chinese nurses were recruited from all hepatological surgery departments in Hunan Province and filled out an online questionnaire to collect data on socio-demographics, role stress, burnout, psychological distress, and social support. Mediation and moderation analyses were carried out in SPSS macro-PROCESS.Burnout partially mediated the positive association between role stress and psychological distress. Social support moderated the indirect effect of role stress on psychological distress via burnout, with the effect being stronger for nurses with low social support than those with high social support.These findings demonstrated how role stress contributed to nurses' psychological distress both directly and indirectly through burnout, and how this indirect effect was moderated by social support. The results provide important practical implications for future prevention and intervention programs to improve nurses' mental health from multiple aspects such as decreasing role stress and burnout while increasing social support. The Coronavirus disease 2019 (COVID-19) and its global pandemic have become a serious global mental health concern all over the world, bringing about a sharp increase in the number of mental health problems such as loneliness, depression, and anxiety –5. It haGlobally, role stress is a common and widespread phenomenon in healthcare and nurses are particularly at high risk of role stress due to high job demands, rapidly changing environments, facing patient's suffering and death, work overload, and insufficient support, which has been highlighted in several literature reviews –12. ThisRole stress is a leading contributor to psychological distress including stress, depression, and anxiety, which is also a prevalent phenomenon among nurses, especially under the global pandemic of Covid-19 , 18. A rThe concept of role stress was first brought about by Kahn et al. , 21 in 1According to Schotte and Clum's diathesis-stress model , stress Burnout is a psychological syndrome that develops in response to prolonged stressful working conditions and typically includes three dimensions: emotional exhaustion, depersonalization, and decreased personal accomplishment , 28. EmoAs a job-specific phenomenon, burnout has been a heated research topic in studies on nurses' well-being –31. BurnAlthough role stress may be related to psychological distress through burnout, not all nurses with role stress equally suffer from burnout and develop psychological distress. One of the most important and widely studied factors that may moderate the effect of role stress on psychological distress via burnout is social support. Social support is a multidimensional concept that involves various aspects of resources one perceived that come from various sources, such as family, friends, and co-workers , 40. An While it has been well-established that higher role stress may lead to psychological distress, less well-known is the indirect effect of role stress on psychological distress via burnout, and whether this effect was moderated by social support. The Job Demand-Resources Model (J-DR model) provides a suitable model to understand the mediating and moderating mechanism underlying the relationship between role stress and psychological distress , 48. AccBased on the J-DR model, we proposed this study's conceptual model as shown in Hypothesis 1. Role stress would be positively associated with nurses' experience of psychological distress including stress, depression, and anxiety.Hypothesis 2. Burnout would mediate the relationship between role stress and psychological distress.Hypothesis 3. Social support would moderate the direct and indirect relations between role stress and psychological distress.This was a cross-sectional study conducted among nurses of hepatological surgery departments in Hunan Province from June to July 2021. For this study, the inclusion criteria consisted of direct care nurses working in hepatological surgery departments. We included all hospitals in Hunan Province that have set up an independent hepatological surgery department. We achieved information of all hepatological surgery departments in Hunan Province through the Hepatobiliary Health Education Chair of Hunan Province and contacted the head nurse of each department to get a list of nurses, leading to a sampling frame of 856 nurses in the hepatological surgery department. The study was conducted online, with all questionnaires produced, distributed, and collected with the online survey tool Sojum . Sojum iSix hundred and twenty-three nurses completed the questionnaire. All nurses are required to fill out each item of the questionnaire to be able to submit the online questionnaire and as a result, there is no missing data in the final dataset. Most of the nurses are female (98.72%), and only 8 (1.28%) were male. The nurses' age ranges from 20 to 58, with an average age of 30.88 (SD = 6.14). Two-thirds of nurses were married (66.93%), and most had an education level of college and above (81.86%). Their working years in nursing ranges from 0.5 to 37, with an average year of 9.48 ± 6.52. In terms of professional and technical titles, the primary level accounted for 50.9%, the middle level accounted for 42.4%, while the higher level accounted for 6.7%.Role stress was measured using the Role Conflict, Ambiguity and Overload Scale (RCAOS) developed by Peterson . The RCABurnout was measured using the Maslach Burnout Inventory (MBI) developed by Maslach and Jackson . The MBIPsychological distress was measured using the Depression Anxiety Stress Scale 21 (DASS-21) developed by Lovibond and Lovibond . The DASSocial support was measured using a self-designed scale that included three questions asking about the level of support participants received from family, supervisor, and colleagues. Each item is rated on a five-point Likert scale ranging from “1” (extremely unsupportive) to “5” (extremely supportive). Sample items included “To what degree is your family supportive of your nursing work?”. The total score ranges from 3 to 15, with higher scores representing higher levels of social support. In the current study, the social support scale showed acceptable internal consistency with a Cronbach's alpha coefficient of 0.70.All data analyses were conducted using SPSS v 23.0. First, descriptive analysis and correlation analysis were conducted among variables. Second, a simple mediation analysis of burnout mediating the relationship between role stress and psychological distress was tested using Hayes's PROCESS macro for SPSS (Model 4) . Third, r = 0.39, p < 0.001) and psychological distress , but negatively associated with social support . Burnout was positively associated with psychological distress , but negatively associated with social support . Psychological distress was negatively associated with social support .t = 14.30, p < 0.001), and on burnout . When the mediating variable burnout was added, the direct effect of role stress on psychological distress was still significant , indicating partial meditation. Burnout had a significant positive effect on psychological distress .Further bootstrapping results showed the total effect of role stress on psychological distress was 0.84 , with a direct effect of 0.59 , and an indirect effect of 0.25  through burnout. All these intervals didn't include zero, indicating that burnout partially mediated the relationship between role stress and psychological distress, with an indirect effect accounting for 29.76% of the total effect.t = 7.77, p < 0.001), and the product of role stress and social support had no significant effect on psychological distress , indicating that social support didn't moderate the direct effect of role stress on psychological distress.In our proposed moderation mediation model, we hypothesized that social support would moderate all pathways in the mediation process of role stress on psychological distress through burnout. t = 8.54, p < 0.001), and the product of role stress and social support had a significant effect on burnout , indicating that social support moderated the effect of role stress on burnout. Further simple slope analysis results are shown in bsimple = 1.35, t = 6.97, p < 0.001). As the social support increased to the middle (M) and high level (M + 1SD), role stress also had a positive effect on burnout, but the effect was decreasing gradually , indicating that with the improvement of social support level, the positive effect of role stress on burnout was decreasing gradually.Role stress had a significant positive effect on burnout , and the product of burnout and social support had significant effect on psychological distress , indicating that social support moderated the effect of burnout on psychological distress. Further simple slope analysis results are shown in bsimple = 0.25, t = 9.55, p < 0.001). As the social support increased to the middle (M) and high level (M + 1SD), burnout also had a positive effect on psychological distress, but the effect was decreasing gradually , indicating that with the improvement of social support level, the positive effect of burnout on psychological distress was decreasing gradually.Burnout had a significant positive effect on psychological distress  of the Hunan Provincial People's Hospital (No. Ky-2021-42). The patients/participants provided their written informed consent to participate in this study.YX, HZ, and YY contributed to the conception and design of the study. YX, HZ, QL, SX, TD, and JG contributed to the research conduction and data collection. YX, HZ, and QL contributed to data analyses, while SX, TD, JG, and YY contributed to data interpretation. YX drafted the article while HZ, QL, SX, TD, JG, and YY critically appraised and revised it. All authors approved the final version of the manuscript for submission.This work was supported by the Hunan Provincial Science and Technology Department (No. 2020ZK4063), the Education Department of Hunan Province (No. 20C1121), and the Health Commission of Hunan Province (No. 202114021956) in support of the corresponding author. The funder had no role in the design of the study, collection, analysis, interpretation of data, and in writing this manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Femur Head Necrosis (FHN) is a common clinical joint orthopedic-related disease, and its incidence is increasing year by year. Symptoms include dull pain and dull pain in the affected hip joint or its surrounding joints. More severely, it can lead to limited joint movement and inability to walk autonomously. Surgical treatment has many sequelae. The high cost makes it unaffordable for patients, and the side effects of drug treatment are unknown. A large number of clinical studies have shown that acupuncture is effective in treating femoral head necrosis. Therefore, this systematic review aims to explore the safety and effectiveness of acupuncture in the treatment of femoral head necrosis.P < .1 and I2 > 50% are the thresholds for the tests. We will utilize the fixed effects model or the random effects model according to the size of heterogeneity.We will conduct a comprehensive literature search in Medline, PubMed, Cochrane Database of Systematic Reviews, Embase, Chinese Biomedical Literatures Database (CBM), China National Knowledge Infrastructure (CNKI), Wang FangDatabase (WF), Chinese Scientific Journal Database (VIP) from inception to May 2021 without any language restriction. In addition, we will retrieve the unpublished studies and the references of initially included literature manually. The two reviewers will identify studies, extract data, and assess the quality independently. The outcomes of interest include: total effective rate; the total nasal symptom score; Hip function ; Adverse events. Randomized clinical trials will be collected, methodological quality will be evaluated using the Cochrane risk-of-bias assessment tool, and the level of evidence will be rated using the Grading of Recommendations, Assessment, Development and Evaluation approach. Meta-analysis will be performed using RevMan 5.4.0 software. The heterogeneity test will be conducted between the studies, The meta-analysis program will systematically evaluate the efficacy and safety of acupuncture in the treatment of FHN patients.This study will investigate whether acupuncture can be used as one of the non-surgical and non-pharmacological therapies for the prevention or treatment of FHN.INPLASY202150035. The nature of the pain is described by most patients as a deep, intermittent, paroxysmal pain. The pain is usually limited to the groin area, or involves large and small tuberosity areas, and the pain is radioactive, radiates to the hip and knee on the same side, weight-bearing and aggravation after activities, in more serious cases will lead to limited joint activities. Recent animal experiments have shown that glucocorticoids can reduce the expression of β-catenin and c-Myc downstream of the Wnt pathway, leading to the apoptosis of bone cells and osteoblasts, which in turn causes early hormonal FHN. DKK1 is a Wnt pathway inhibitor that can regulate the development of bone tissue. Alcoholism promotes the expression of DKK1, which in turn causes a large number of bone cell apoptosis and promotes the progression of FHN. In addition to the effects of hormones and alcohol abuse, blood flow disorders of the femoral head,,8 lipid metabolism disorders, increased intra-articular pressure, osteoblast apoptosis,,12 gene specific risk factors such as polymorphism, family history of FHNand other related diseases can affect microcirculation in some way. Domestic and foreign scholars have done a lot of research on the pathogenesis of FHN, but no breakthrough has been made so far. But what we knew is that the common developmental endpoint of diseases are caused major risk factors such as abnormal microcirculation and necrosis, and subsequent collapse of subchondral bone, eventually leads to the occurrence of FHN.The occurrence of FHN is related to many factors, but the underlying specific pathogenesis is unclear. Globally, FHN has a high probability of disability, which seriously affects people's health and quality of life.,18 In the United States, there are about 20,000 new FHN patients every year. In the United Kingdom, the average age of onset of FHN is 58.3 years, and the prevalence rate is 2 out of every 100,000 people with this disease. In German-speaking countries, the incidence of FHN is 0.01%, and 5000 to 7000 people suffer from this disease every year. Japanese scholars Ikeuchi K, Hasegawa Y found that the annual incidence of non-traumatic FHN in Japan is about 1.9 per 100,000. In addition, in China, an epidemiological study found that in the general population, about 8.2 million Chinese people over the age of 15 are affected by the disease. If FHN is not treated in time, 90% of patients will experience femoral head collapse within 5 years, and then joint dysfunction will eventually lead to paralysis.FHN can be seen at any age, and there is no gender difference. Moreover, the cost of THA is prohibitive. In recent years, studies have shown that the cost of THA in China is between 8000 and 10,000 US dollars, which brings both patients and the country posed a huge economic and social burden. At present, there are generally two non-surgical treatment methods: physical therapy and drug therapy. Physical therapy includes hyperbaric oxygen (HBO) and pulsed electromagnetic field (PRMF). HBO has significant effects but requires continuous treatment. The course of treatment is longer, PRMF can only slightly delay the process of FHN, and the course of treatment is not significant. Relevant drug treatment: Western medicine treatment generally uses statin lipid-lowering drugs, alendronate sodium, etc., statin lipid-lowering drugs have a significant effect on hormone-induced FHN, but for FHN caused by other reasons, its efficacy is unknown. Alendronate has a significant effect on early FHN, but it has no significant effect on late disease. Recent studies have shown that: Chinese medicine has its unique advantages in the treatment of this disease. FHM treats four types of phlegm and blood stasis blocking the collaterals, qi stagnation and blood stasis, obstruction of meridians, and liver and kidney deficiency. The main treatment methods include dredging collaterals and removing numbness, activating blood stasis, replenishing liver and kidney. Zhiguo Liu et al have verified through animal experiments that epimedium and core decompression can reduce blood rheology indexes, improve local microcirculation around joints, promote bone growth, accelerate the repair of damaged tissues and has a good effect. Liao Hongwei et al. used Fuyang Huogu Pills combined with core decompression to treat 68 patients with early FHN. Follow-up showed that this method can greatly reduce the probability of patients undergoing THA. However, there is no direct evidence to prove that there are single Chinese medicines or prescriptions that have a significant effect on FHN, and both require core decompression therapy or THA surgical intervention. Therefore, FHN patients need a safe and effective alternative therapy to alleviate the pain caused by the disease.Based on the characteristics of FHN patients with high harm, high morbidity, poor prognosis, femoral head collapse and hip joint destruction at the end of the disease, most doctors will recommend that patients undergo surgical intervention, that is, the characteristics of artificial total hip arthroplasty (THA), but THA surgery has certain adverse effects.,34 Some studies have found that the mechanism of acupuncture treatment of FHN may be related to the improvement of peripheral blood TNF-α and VEGF levels. Of course, some studies have shown that acupuncture combined with drug treatment can improve the hemodynamics of patients, improve hip joint function, reduce the volume of necrotic area, increase the gray scale of osteonecrotic area and femoral head.Acupuncture therapy is one of them. This therapy is currently commonly used in combination with drugs and core decompression to treat FHN-induced pain around the hip joint, and the effect is remarkable, and it is gradually accepted and used.,38In addition, it originated from traditional Chinese medicine (TCM)'s thinking that “treatment is as good as treatment itself” and that “health is maintained and not harmful to others”. Acupuncture therapy has the characteristics of regulating qi, blood, yin and yang, preventing diseases, having fewer side effects, and being easily accepted by patients. Therefore, it has gradually become popular around the world.Although the effects of acupuncture and moxibustion have been widely confirmed, the effectiveness and safety of acupuncture in the treatment of FHN are still controversial. System review or Meta analysis has been considered as the basis for evaluating clinical efficacy and formulating clinical guidelines. Therefore, this study adopts the method of evidence-based medicine to systematically analyze and evaluate randomized controlled trials (RCTs) of acupuncture and moxibustion treatment of patients with FHN to provide a basis for verifying the efficacy. So far, the number of patients with femoral head necrosis has increased, and the simplicity and low side effects of acupuncture therapy have attracted the attention of clinicians at home and abroad. Randomized controlled trials (RCT) of acupuncture treatment of femoral head necrosis have also increased simultaneously. At present, there is still a lack of relevant systematic reviews in clinical practice. Therefore, this systematic review focuses on the safety and effectiveness of acupuncture in the treatment of femoral head necrosis, in order to cope with patients who cannot afford high surgical costs, adverse drug reactions or who wish to receive acupuncture treatment, so that they can better serve the clinic.System analysis helps to evaluate the effectiveness and credibility of clinical methods.22.1https://inplasy.com/inplasy-2021–5–0035) can be used to verify its legitimacy. This article does not require ethical approval because it simply examines FHN acupuncture treatment that has been documented in multiple databases. The protocol is based on the Cochrane Handbook for Systematic Reviews and Meta-Analysis Protocol  (PRISMA-P).This system evaluation plan has been registered on the International Prospective Register of Systematic Reviews (registration number INPLASY202150035). This webpage  and the control group must be treated with non-acupuncture therapy.2.2.4Massage, medicine , routine symptomatic therapy, and other intervention methods may be utilized in the control group, but acupuncture should not be employed as the sole requirement.1.Acupuncture therapy vs no treatment;2.Acupuncture therapy vs placebo;3.Acupuncture therapy vs sham acupuncture;4.Acupuncture therapy vs symptomatic or active treatment;2.2.52.2.5.1Both the total effective rate and hip function  were the primary outcomes. The total score of nasal symptoms will be scored according to the patient's disease history, symptoms, signs and imaging.2.2.5.21.Hip function ;2.Hip pain score ;3.Progress of imaging staging of femoral head necrosis Rate ;4.volume percentage of femoral head necrosis;5.Total hip replacement rate.2.3Before and after therapy; Acupuncture is present in the control group; Repeated literature, theoretical discussion and review literature, nursing literature, animal experimental research, etc.2.4We will search the following databases: PubMed, Cochrane Database of Systematic Reviews, Embase, Chinese Biomedical Literatures Database (CBM), China National Knowledge Infrastructure (CNKI), Wang FangDatabase (WF), Chinese Scientific Journal Database (VIP) from their inception to May 2021. The main subject terms searched: “acupuncture”, “femur head necrosis”, “osteonecrosis of femoral head”, “avascular necrosis of femur head”, “ANFH”, “ONFH”, Pubmed's search strategy is shown in Table 2.5We will deal with the included literature in the following way and the specific operation is as follows: Firstly, according to the selected topic, the retrieved literature is imported into noteExpress 3.0 in the document manager in the correct retrieval way, and remove the duplicate published article in the document manager; Then, by reading the title and abstract one by one, the article irrelevant to this research will be weeded; then, the remaining articles will be downloaded in sequence and the full text will be read; finally, based on the inclusion and exclusion criteria required in this article, the final paper will be framed;For this operation, 2 researchers  strictly follow this procedure. If they disagree, consult the third evaluator (Hongyu Wang) for negotiation. The included article process is shown in Figure 2.5.1In the final article, two researchers  independently extracted information and entered it into word 2010. After the end, they were cross-checked. If there are any doubts, they can contact the third evaluator (Hongyu Wang) Negotiate processing to ensure the accuracy of the information. The extracted information includes: title, Author, year of publication, sample size, intervention measures and treatment course, etc. When some important information is missing in the input data of some articles, contact the author by phone or email.2.5.2 The main contents are: Random method; allocation concealment; implementation of blind method; blindness of the outcome rater; completeness of the result data; selective reporting of results; other biases. Each of the above three items contains “yes”, “no” and “unclear”. The two assessors  need to evaluate the options that meet the conditions. If there is any dispute among them, they can discuss and deal with a third party (Hongyu Wang).Use the Cochrane Reviewer's Handbook 5.0 to evaluate the quality of the final selected literature and assess the risk of bias.2.62.6.1Enumeration data will be represented by odds ratio (OR) and 95% confidence interval (CI), measurement data are represented by weighted mean difference (WMD) and 95% confidence interval (CI) or standardized mean difference (SMD) should be used when the units were not unified.2.6.22 test. When P > .1 and I2<50%, use fixed effects model; Otherwise, use random effects model. Sensitivity analysis will be used if the heterogeneity is large. If there is substantial heterogeneity, it can be analyzed descriptively. Use Review Manager 5.4.0 line inverted funnel chart to qualitatively analyze publication bias.When performing heterogeneity test, use I2.6.3If the number of remaining articles is more than 10, we can use Review Manager 5.4.0 line inverted funnel chart to qualitatively analyze the publication bias. The graph shows the approximate shape which represents the publication bias.2.6.4If there is large heterogeneity, we will conduct subgroup analysis based on different control measures.2.6.5The sensitivity analysis should be performed to assess the reliability of the meta-analysis, Analysis software uses STATA 14.0 software for sensitivity analysis.3This review is the first of the current modern literature on the treatment of FHN by acupuncture and moxibustion. The purpose of this review is to find evidence of the benefit of acupuncture and moxibustion in the treatment of FHN. Based on the discussion part of this paper, following aspects are presented in detail:1.Study on TCM pathogenesis of FHN2.Advantage, disadvantages and mechanisms of acupuncture and moxibustion treatment of FHN3.Horizontal comparison with other treatment methods or viewpoints;4.Explain the results;4,44 Currently, there is no systematic and scientific evaluation of acupuncture for FHN, so this paper aims to provide an evidence-based medical perspective on the safety of acupuncture for FHN. Of course, this study still has some limitations: First, the quality of the article is not high, which may affect the evaluation results; Second, the paper is limited in Chinese and English language, which may lead to incomplete literature retrieval; Third, contacting the article's author may be impossible, resulting in inadequate data results. As a result, more high-quality randomized controlled trials and research procedures are needed to demonstrate its efficacy, allowing for a more objective assessment of acupuncture's safety and efficacy in FHN.Acupuncture has a history of thousands of years and has been used by doctors at home and abroad as a complementary and alternative therapy. The use of acupuncture as a non-surgical treatment is gradually spreading. Acupuncture treatment has become the dominant disease of hip pain and other diseases, and intervention may play a role by regulating a variety of pathways and activating a variety of medium.Conceptualization: Hongyu Wang.Data curation: Fengyun Yang.Formal analysis: Hongyu Wang, Zhiwen Cao.Methodology: Jiangyuan Liu.Software: Yunfeng Luo.Supervision: Wenlong Yang.Validation: Wenlong Yang.Writing – original draft: Zhijun Yang, Fuwei Li.Writing – review & editing: Zhijun Yang, Hanting Xia, Zhaochong Mao.


Colorectal cancer is one common digestive malignancy, and the most common approach of blood metastasis of colorectal cancer is through the portal vein system to the liver. Early detection and treatment of liver metastasis is the key to improving the prognosis of the patients. Radiomics and radiogenomics use non-invasive methods to evaluate the biological properties of tumors by deeply mining the texture features of images and quantifying the heterogeneity of metastatic tumors. Radiomics and radiogenomics have been applied widely in the detection, treatment, and prognostic evaluation of colorectal cancer liver metastases. Based on the imaging features of the liver, this paper reviews the current application of radiomics and radiogenomics in the diagnosis, treatment, monitor of disease progression, and prognosis of patients with colorectal cancer liver metastases. Colorectal cancer (CRC) is the third most prevalent malignancy and the second commonest cause of cancer-related deaths throughout the world , with thWith the development of great-volume computing capability, it is currently feasible to quickly extract countless quantitative characteristics from three-dimensional imaging data of MRI, CT, ultrasound, and PET for evaluation of the nature of different lesions, because digital medical images contain considerable information that reflects potential pathophysiology. This technology of transforming digital medical imaging data into high-dimensional data for assessment and decision support is referred to as radiomics . The fraRadiogenomics refers to the exploring of radiomics data to find correlations with genomic modes and has aroused considerable interest in the research field of oncology . Here, iIn patients with CRC, one factor significantly affecting the prognosis is the proper management of colorectal cancer liver metastases (CRLM), and surgical treatment stands for the only opportunity of long-term survival. The 5-year survival rate of CRC patients with complete resection of liver metastases has been reported to be approximately 30% higher than that without appropriate treatment of the liver metastases . TherefoIn recent years, the field of medical image analysis has developed rapidly, and the development of pattern recognition tools has promoted fast progress of quantitative feature extraction. By extracting a great deal of quantitative features from medical imaging data, radiomics can be used to analyze image information in detail. Compared with traditional approaches of imaging diagnosis, it can significantly improve tumor diagnosis, grading and staging, evaluation of responses to chemotherapy, and prognosis prediction , 17, 18,n = 10), heterochronous hepatic metastasis within 18 months after initial staging (n = 4), or no hepatic metastasis (n = 15), Rao et al. (p < 0.05) higher in patients with synchronous metastases than those without hepatic metastases, whereas the mean uniformity of the whole liver was significantly (p < 0.05) lower in patients with synchronous metastases than those without liver metastases. This study indicated that texture evaluation of seemingly disease-free liver is promising to distinguish CRC patients with or without hepatic metastases. After analyzing the texture in non-enhanced CT imaging in seemingly non-diseased regions of liver for impact of hepatic texture by presence of malignant tumors in patients with CRC, Ganeshan et al. (p < 0.05) different in seemingly non-diseased hepatic areas in patients with hepatic metastasis compared with those without liver metastasis  or those with extra-liver disease . Imaging textures of entropy and uniformity have been found to be more advantageous to other features in the diagnosis of CRLM.With the progress of imaging technology, conventional imaging approaches can effectively detect large and typical CRLM. However, due to the complexity of hepatic hemodynamics and differences of liver parenchymal background on imaging among patients, different imaging modalities perform differently in diagnosis of atypical or tiny liver metastases. It is hard to detect tiny or occult metastases by using the existing imaging approaches; however, identification of these lesions is crucial to early management and improved prognoses. Radiomics features, including entropy, texture and texture ratio, uniformity, and convolutional neural networks (CNNs), have been effectively applied for diagnosis of CRLM. In assessing the capability of whole-liver CT imaging texture analyses of hepatic parenchyma in distinguishing CRC patients with simultaneous hepatic metastasis . The combined model had good discriminating capability, with the AUC of nomogram being 0.971, 0.909, and 0.905, respectively, in the training, internal validating, and external validating set. Their study (The HGPs of CRLM can be effectively differentiated using multidetector CT-based radiomics and MRI-based radiomics (multi-habitat and multi-sequence) , 30. Aftir study  revealedn = 367) had desmoplastic growth in the whole tumor–hepatic interface and were independently associated with 50% 5-year survival rate without progression  and 78% 5-year overall survival . CRLM lesions with this kind of HGP are more suitable for regional metastases-directed treatment. On the contrary, replacement HGP is linked to poor pathological responses, with the presence of a large proportion of cancerous cells after chemotherapy, and bad imaging reaction on CT in patients with primary chemotherapy and anti-angiogenesis therapy before surgery for CRLM  (p < 0.001) and the angular second moment of 0.96 ± 0.02 vs. 0.98 ± 0.01, respectively (p < 0.001).The entropy of CRLM lesions had been reported to decrease in patients with good responses while the uniformity increased after chemotherapy  . However = 0.08) , and a l = 0.08) . Two meap < 0.05) differences in Entropy, Energy, Variance, Standard deviation, Quantile 95, and sumEntropy between the response and non-response groups in pre-treatment lesions. Lesions with higher Entropy, lower Energy, higher Variance, higher Standard Deviation, and higher sumEntropy seemed to indicate a better therapeutic response. Good diagnostic efficiency was obtained when sumEntropy > 0.867, with a sensitivity of 60.5% and a specificity of 79.5%. Radiomics texture indexes originating from basic CT imaging data of CRLM lesions had the potential capability of imaging biomarkers for predicting cancer response to targeted chemotherapy. By comparing the image features before and after diagnosis and treatment, we found statistically significant radiomics features, such as Entropy, Energy, Variance, Standard deviation, and Quantile, which can all be used to evaluate the remission effect of drugs on CRLM lesions. In the future, these radiomics features can be used clinically as a relatively cheap and noninvasive monitoring means for patients with CRLM or other malignancies.After investigating therapeutic radiomics features for predicting tumor sensitivity in 667 patients with CRLM to 5-fluorouracil, irinotecan, and folinic acid alone or combined with cetuximab, Dercle et al.  found thp < 0.05) independently associate with good responses to chemotherapy (AUCs 0.602–0.784). Multivariable logistic regression demonstrated that variance (p < 0.001) and angular second moment (p = 0.001) remained predictive parameters to distinguish responding from non-responding tumors, with the highest AUC of 0.814  (p < 0.001) in the validation setting. The CRLM heterogeneity at 18F-FDG PET/CT was also confirmed to be a predictor of shorter overall survival (HR 4.29) at multivariant analysis (p < 0.001)  . After c × 1049) , with thanalysis , and a m< 0.001) .Entropy of the metastatic lesions had been associated with the prognosis of patients with CRLM , 41, 50.Other radiomics features have also been related to the survival. The combination of CRLM correlation and contrast into a single texture parameter had been reported to associate with overall survival (HR 2.35) . One texIn addition to the above mentioned radiomics features, CRLM density on CT imaging , ShapeSIRadiogenomics can be used to discover the radiomics features that reflect gene expression or polymorphism for further understanding the occurrence and development of diseases . RadiogeCurrently, there are only limited studies on radiogenomics of tumors involving the liver. Segal et al. were the first in 2007 to explore the correlation of gene expression pattern of a hepatocellular carcinoma with the imaging features, identifying 32 image characteristics from enhanced CT imaging of three phases to be correlated to the expression degrees of 116 genetic biomarkers among 6,732 genes confirmed by microarray analysis . HoweverCRC is a heterogeneous tumor, and its occurrence and development are affected by a variety of factors. Lifestyle habits such as high-fat diet are important risk factors to increase the incidence of CRC . BesidesThe RAS/RAF/MEK/extracellular signal-regulated kinase signaling cascade is referred to as the pathway of mitogen-activated protein kinase (MAPK), which controls cellular differentiation, proliferation, angiogenesis, migration, and survival. Dysregulation of the pathway constitutes the bases for tumorigenesis . This paKRAS, NRAS, and HRAS are the RAS oncogenes to encode a family of GTP-adjusted switches and can repeatedly mutate in human cancers . Once acKRAS gene is related to the pathogenesis and progression of CRC, and mutation of this gene may cause resistance to EGFR inhibitors and poor tumor response to molecular targeted drugs , 76. De NRAS defines a group of molecules with different clinical features from KRAS-mutant and wild-type metastatic CRC . NRAS geBRAF mutations take place in 7% of cancers, and approximately 8%–12% of metastatic CRC cases contain BRAF mutations . BRAF gep < 0.001), with the AUC, sensitivity, and specificity for predicting KRAS/NRAS/BRAF mutation as 0.869, 0.757, and 0.833 in the primary group, and 0.829, 0.686, and 0.857 in the validation group, respectively.Yang et al.  studied p = 0.007), mean positive pixels , and standard deviation  of medium filtration were significantly associated with the tumor stage. Skewness was found to negatively associate with KRAS mutations (p = 0.02), whereas the coarse filtration entropy was significantly (p = 0.03) associated with survival (HR for death 0.65). Therefore, radiogenomics is expected to understand the gene expression profile of the disease through noninvasive and routine imaging examination and may be a breakthrough in the diagnosis, treatment, disease monitor, and prognosis evaluation of CRC and CRLM.Lubner et al.  investigvia its association with CpG methylator phenotype  which occurs in 15% patients with CRC. MSI tumors are a subset of CRC characterized by malfunction of mismatch repair genes (MMR), which can cause failure to repair errors in short tandem repetitive DNA sequences known as microsatellites , 83. In henotype .High-frequency MSI (MSI-H) refers to the occurrence of MSI at two or more sites; low-frequency MSI (MSI-L) is MSI occurring only at one site; microsatellite stability (MSS) indicates MSI, which does not occur at any site , 86. MSIUnderstanding the MSI status is necessary because CRC tissues with MSI have specific biological behavior and may indicate better prognoses and benefit from immunotherapy or resistance to fluorouracil treatment . HoweverFan et al. studied 119 patients with stage II CRC confirmed pathologically, known MSI status, and preoperative enhanced CT images for extracting radiomics features . In theiIn exploring the value of radiomics analysis derived from dual-energy CT imaging to preoperatively evaluate the MSI status in CRC, Wu et al.  investigAlthough there is consistency between CRC MSI status and liver metastasis, there were currently no correlation studies between MSI status and radiomics of liver metastasis.In the diagnosis, treatment, monitor of disease progression, and prognosis of CRLM, thousands of radiomics features can be extracted, such as image intensity features, high-order features, texture features, and shape features. Due to the lack of unified standards at present, different research teams choose different radiomics features in the selection of features. Through review of published studies in the literature, it is found that the most widely used radiomics features include entropy, uniformity, variance, and skewness. At present, the unity of the results is relatively poor, but all these results show the feasibility and significance of the application of radiomics and radiogenomics in the diagnosis, treatment, monitor of disease progression, and prognosis of CRLM.Radiomics and radiogenomics can be widely used in clinical medicine research with noninvasiveness and low cost. However, as a new field, it is still in its infancy, with many limitations. For example, the research data for radiomics mostly come from small samples and single centers, whereas some big data from multicenters are different because of use of different scanning equipment and scanning conditions. Moreover, imaging delineation segmentation approaches may also differ from center to center or from study to study. Future development and research in radiomics and radiogenomics will have to solve these issues for better outcomes.As an innovative arena in medical imaging, radiomics and radiogenomics can be used to identify pathological process, reveal the underlying pathophysiological mechanisms through medical imaging and clinical data, and identify hidden imaging patterns that can be used to predict tumor biological behavior and patients’ prognoses, providing efficient prediction of responses to chemotherapy and survival in addition to accurate and early prediction compared to standard biomarkers. Continuous surveillance of the radiomics and radiogenomics biomarkers will provide adequate information to monitor cancer recurrence and individualized treatment to the constantly changing genome of cancer. The current research results in radiomics and radiogenomics of CRLM warrant further exploration into wider application in other fields.Study design: X-PY and B-LG. Data collection: YW and L-YM. Supervision: L-YM. Writing of the original version of article: YW. Revision of the original version: B-LG. All authors contributed to the article and approved the submitted version.This study is funded by Hebei Natural Science Foundation Project (H20212017), Project of Hebei Provincial Department of finance (361007), and Medical Discipline Cultivation Project of Hebei University (2020b05).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


The relation between tumor sites of pancreatic ductal adenocarcinoma (PDAC) and recurrence was not fully investigated before. We aimed to describe the differences of recurrent patterns in PDAC of head and body/tail after curative surgery.  The recurrent patterns of PDAC were compared and the associations with clinical characteristics were analyzed in these patients. Prognostic factors of overall survival (OS) and progression-free survival (PFS) were analyzed and validated. Predictive systems were constructed and measured by the area under the AUC curve and concordance index (C-index).  A total of 302 PDAC patients were included in this study, including 247 patients with PDAC of head and another 55 patients with PDAC of body/tail. Patients who developed tumor recurrence within 24 months after resection had significantly shorter OS in both groups. Liver metastasis occupied most of the tumor progressions and diminished while local recurrence increased gradually over time. The variation trends were similar for patients in both groups while these changes were more pronounced for patients in the head group. Local recurrence and liver-only metastasis seemed to indicate a better OS. Furthermore, predictive systems for OS and PFS prediction based on independent risk factors were established and showed significant higher values of AUC and C-indexes compared with the TNM stage system.  Different characteristics of progressions for PDAC of head and body/tail suggested biological heterogeneity. The exploration of these variations helps to provide personalized management of recurrence in PDAC. As a lethal disease with increasing morbidity, pancreatic ductal adenocarcinoma (PDAC) is predicted to cause the second most number of cancer-specific deaths by 2030 . SurgeryDifferent sites of tumors were shown to have different characteristics , 9, indiAs a continuous study of our previous research, the inclusion and exclusion criteria were reported before . BrieflyAll included patients had received radical resection and the pathological diagnosis of PDAC was finished by an experienced pancreatic pathologist. The following pathological factors were analyzed, including tumor size, differentiation, lymph node (LN) metastasis, LN total and positive number, satellite foci, vascular, lymph vessel, perineural and adjacent organ invasion, and combined venous resection. Lymph node ratio (LNR) is defined as the ratio between the number of positive LNs and the total number of examined LNs. In addition, the associated radiological and clinical variables, which had been described in our previous studies , were coInformation on recurrence patterns was obtained through strict follow-up after surgery. Either radiological or histological evidence was required for the diagnosis of recurrence of disease. The specific recurrence pattern was defined as the first location of recurrence. Similar with the study of Groot et al. , five caP values were two-sided and P values < 0.05 were considered significant. R software version 3.6.1  was used to conduct all statistical analyses.The follow-up of patients occurred at the outpatient clinic of our hospital. In general, follow-up strategies consisted of regular chest computed tomography (CT), abdominal CT, and CA19-9 test, at least every 2 months during the first year after surgical resection and every 3 months thereafter. Occasional additional imaging modalities, such as magnetic resonance imaging (MRI) and positron emission tomography/CT (PET/CT), were selectively performed to determine patterns of recurrence. Patients who had LN metastases or other risk factors, including macrovascular or microvascular invasion, and lymph vessel invasion, were recommended to receive chemotherapy. Two survival outcomes were analyzed in this study, including progression-free survival (PFS) and overall survival (OS), defined as the time from surgery to progression and death, respectively, or last follow-up. In addition, post-progression survival (PPS), defined as the time from first tumor progression to death or last follow-up, was also evaluated in this study. The date of the last follow-up was at the end of May 2019. Kaplan–Meier method was used to estimate survival and the differences of survival were compared with the log-rank test. Factors that were statistically significant in the univariable analysis and least absolute shrinkage and selection operator (LASSO) logistic regression were candidates for entry into a multivariable analysis. Area under the receiver operating characteristic (ROC) curves (AUC) and concordance index (C-index) of the multimarker algorithms were calculated to compare the predictive efficacy of risk factors with that of the tumor-node-metastasis (TNM) stage system. All Between 2008 and 2018, 355 patients underwent surgical resection and were histologically confirmed PDAC at SYSUCC. A total of 53 patients who did not meet the criteria for inclusion were excluded from this study: 10 patients with microscopic or macroscopic incomplete resection, 12 patients with second primary tumors, and 31 patients with incomplete follow-up information. Finally, there were a total of 273 patients who were diagnosed with resectable diseases and another 29 patients diagnosed with borderline resectable diseases. All patients have received radical resection (R0 resection). All patients were followed up for more than 1 year and the median follow-up time was 24.7 months [95% confidence interval (CI) 20.3–29.1] after surgery. Tumor recurrence was detected in a total of 173 (57.3%) patients while there was no recurrence in 129 (42.7%) patients. For patients with and without recurrence, the median follow-up time was 13.8 and 40.6 months, respectively .According to the primary tumor sites, patients were sorted into the head and body/tail groups, respectively. There were 247 patients in the head group and another 55 patients in the body/tail group. A total of 140 and 24 patients in the head and body/tail groups were younger than 60 years, respectively. Male patients accounted for 40% of all patients in both groups. The median values of tumor size were 3.5 cm (range 1.0–8.9) and 3.9 cm (range 2–10) in the head and body/tail group, respectively. The mean number of LN retrieved is 12.89 and the median value is 12. Similar ratios of LN metastasis were observed in both groups.Overall, among 173 patients who had developed recurrences, most patients had done so within 24 months. Patients with tumor progressions had significantly shorter survival than those without recurrences. In terms of survival comparisons, patients in the head group seemed to have longer OS while the survival differences were not significant . It was P < 0.001). This trend could be observed in the whole, head, and body/tail groups, and it was more obvious in patients of the head group. In addition, these changes could also be reflected in the correlations of different patterns of recurrences, which are shown in A total of six types of recurrence were recorded for progression. Liver metastasis occupied most of the tumor progression types, followed by local progression, local and distant progression, and lung metastasis. Metastases in other sites or multiple metastases contributed to only a small part of all tumor progressions. Similar proportions of recurrence patterns were observed in both groups. The comparisons of distributions for these recurrence patterns in the whole, head, and body/tail groups are shown in Varied progression patterns contributed to different cumulative survival rates. It was indicated that patients with multiple metastases shared significantly shorter OS and PPS than those with other types of progression patterns, whereas the survival rates of local, lung only, liver only, other sites, and local plus distant metastases were similar in patients of the head and body/tail groups . The paiP=0.002).For patients in the head group, the 1-, 2-, and 3-year OS and PFS were 81.7%, 59.9%, and 48.3%, and 51.7%, 37.5%, and 33.2%, respectively. Similarly, the 1-, 2-, and 3-year OS and PPS were 76.1%, 50.7%, and 40.6%, and 31.4%, 24.4%, and 9.3%, respectively, for patients in the body/tail group. Although no significant variations in OS for patients in the head and body/tail groups were observed, those in the head group had significantly longer PFS, compared with patients in the body/tail group , LN16 metastasis , tumor differentiation , local progression , liver-only metastasis , lung-only metastasis , and local plus distant recurrence  were independent predictors for reduced OS (P=0.007), chemotherapy , imaging tumor size , local progression , liver-only metastasis , lung-only metastasis , local plus distant recurrence , multiple metastases , and TNM stage  were identified as independent predictors for PFS for patients in the head group  and PFS  for PDAC of head (both P < 0.050). In terms of PDAC in the body/tail group, the selected predictive factors also exhibited significantly higher values of AUC and C-indexes compared with the 8th TNM stage system (The predictive power of significant predictive factors was further validated. It was indicated that the values of AUC for 1-, 2- and 3-year OS and PFS prediction were 0.720, 0.734, and 0.801, and 0.749, 0.749, and 0.748, respectively, for patients in the head group. It was shown that compared with the 8e system .As the main reason for poor prognosis, tumor recurrence is the major reason for PDAC after surgery. Similar to those from other studies , 17, it Similar with timing distribution of progression in all patients, tumor progression occurred mainly in the first two years after surgery and this was a linear trend of decrease in recurrence probabilities over time for patients with PDAC of head and body/tail. Around 10.4% of progressions could also be observed 2 years after surgery, showing that recurrence-free survival for two years did not mean cure for PDAC. In addition, the recurrence rate was even higher in PDAC of body/tail. Compared with tumors in the head, those in the body/tail was more likely to progress at two years after surgery. This could be due to the late onset of symptoms of body/tail, leading to more finding of recurrence in two years after surgery.Further analysis for the distribution of progression patterns in PDAC was also conducted. Liver-only metastasis and local recurrence contributed to most of disease progressions for PDAC in the both groups. In addition, when time period to metastasis was considered, it was shown that local recurrence increased gradually and represented a majority of tumor progression forms in two years after surgery. On the contrary, most of liver-only metastasis occurred in the first two years after surgery and diminished over time. This trend for liver-only metastasis was more obvious for all PDACs and PDAC in the head group, compared with those in the body/tail group. Significantly, negative correlations were also observed between liver-only metastasis and other types of tumor progression. Apart from local recurrence, the ratios of lung-only metastasis also increased along with time and PDAC of body/tail was more likely to develop lung-only metastasis compared with PDAC of head. In terms of local plus distant metastasis and multiple metastases, they were mostly observed in early period after surgery in small groups of patients. Considering the changes of progression patterns over time, patients could benefit from the changes of treatment focus during the periods of follow-up for PDAC.Apart from the varied distributions of timing and patterns of tumor progressions, there were also survival differences among different timing and patterns of progressions. Among all types of tumor progression, local recurrence had the longest OS of 29.37 months in the whole groups of patients and 27.6 months in the head group, respectively, followed by other and lung-only metastases. With regard to tumor progression, similar with other studies , liver-oIn the further analysis of the impact of radiological and pathological factors on OS and PFS, it was shown that PDAC in both groups shared most of the risk factors, including time period to progression, tumor differentiation, local progression, and liver-only metastasis. Apart from these risk factors, LN16, lung-only, and local plus distant metastases also indicated significantly poorer survival for PDAC patients in the head group. In addition, the prognostic factors of PFS were also explored in this study. It was indicated that CEA, chemotherapy, local regression, liver-, lung-, local, and distant metastases were independent factors of PFS for PDAC in the head group, while NLR, mGPS, pathological tumor size, and LN size predicted PFS in PDAC in the body/tail group. Decreased time to progression, which reflected a more malignant nature of the disease, indicated poorer survival in both head and body/tail groups, and it was more obvious for the latter. Similar to our study, a pool study of 692 PDAC patients also showed decreased survival due to the decreased time to tumor progression . In termThe predictive systems for OS and PFS prediction were established in this study. Additional independent risk factors were included in the predictive systems, guaranteeing the enhanced strength of the predictive system, compared with the TNM system. On the other hand, the differences of prognosis for PDAC in both groups indicated that probably individual predictive system was needed for these two kinds of diseases, which was reflected by the variations of predictive factors specially designed for PDAC of head and body/tail, respectively. It is well-known that precise prediction of survival is essential for individual treatment. Clinicians can perform evaluation of survival rates based on these independent risk factors and specialize in the adjuvant therapies, which are helpful for personalized medicine.There were several limitations to this study. First, some variables, including specific treatment after surgery, the time period and regimen of chemotherapy, were still unavailable for this study. The inclusion of these variables would further improve the feasibility of the predictive system of survival for PDAC. Second, only the first recurrence was recorded in this study. Third, tumor progressions would be greatly affected by the length of the follow-up period. A longer time period of follow-up was also needed for a more precise overview of tumor progression after surgery. Finally, further validation based on prospective cohorts with more patients was needed for the present study.In conclusion, the comparisons of the timing and patterns of recurrences and investigation of the relations between recurrence characteristics and survival in PDAC of the head and body/tail were conducted in this study for the first time. It was shown that there were some differences in the recurrence timing and patterns of progressions for PDAC of head and body/tail. The associated risk factors for OS and PFS were selected for these two kinds of diseases, respectively. Furthermore, specialized predictive systems were also established and were shown to exhibit great predictive power for survival prediction. The conduction of the predictive system would be greatly helpful for the personalized management for PDAC of head and body/tail after surgery.