Objective To reveal the scientific output and trends in pulmonary nodules/early-stage lung cancer prediction models. Methods Publications on predictive models of pulmonary nodules/early lung cancer between January 1, 2002 and June 3, 2023 were retrieved and extracted from CNKI, Wanfang, VIP and Web of Science database. CiteSpace 6.1.R3 and VOSviewer 1.6.18 were used to analyze the hotspots and theme trends. Results A marked increase in the number of publications related to pulmonary nodules/early-stage lung cancer prediction models was observed. A total of 12581 authors from 2711 institutions in 64 countries/regions published 2139 documents in 566 academic journals in English. A total of 282 articles from 1256 authors were published in 176 journals in Chinese. The Chinese and English journals which published the most pulmonary nodules/early-stage lung cancer prediction model-related papers were Journal of Clinical Radiology and Frontiers in Oncology, respectively. Chest was the most frequently cited journal. China and the United States were the leading countries in the field of pulmonary nodules/early-stage lung cancer prediction models. The institutions represented by Fudan University had significant academic influence in the field. Analysis of keywords revealed that multi-omics, nomogram, machine learning and artificial intelligence were the current focus of research. Conclusion Over the last two decades, research on risk-prediction models for pulmonary nodules/early-stage lung cancer has attracted increasing attention. Prognosis, machine learning, artificial intelligence, nomogram, and multi-omics technologies are both current hotspots and future trends in this field. In the future, in-depth explorations using different omics should increase the sensitivity and accuracy of pulmonary nodules/early-stage lung cancer prediction models. More high-quality future studies should be conducted to validate the efficacy and safety of pulmonary nodules/early-stage lung cancer prediction models further and reduce the global burden of lung cancer.

Objective To analyze the differences in distribution of traditional Chinese medicine (TCM) syndrome elements and salivary microbiota between the individuals with pulmonary nodules and those without, and to explore the potential correlation between the distribution of TCM syndrome elements and salivary microbiota in patients with pulmonary nodules. Methods We retrospectively recruited 173 patients with pulmonary nodules (PN) and 40 healthy controls (HC). The four diagnostic information was collected from all participants, and syndrome differentiation method was used to analyze the distribution of TCM syndrome elements in both groups. Saliva samples were obtained from the subjects for 16S rRNA high-throughput sequencing to obtain differential microbiota and to explore the correlation between TCM syndrome elements and salivary microbiota in the evolution of the pulmonary nodule disease. Results The study found that in the PN group, the primary TCM syndrome elements related to disease location were the lung and liver, and the primary TCM syndrome elements related to disease nature were yin deficiency and phlegm. In the HC group, the primary TCM syndrome elements related to disease location were the lung and spleen, and the primary TCM syndrome elements related to disease nature were dampness and qi deficiency. There were differences between the two groups in the distribution of TCM syndrome elements related to disease location (lung, liver, kidney, exterior, heart) and disease nature (yin deficiency, phlegm, qi stagnation, qi deficiency, dampness, blood deficiency, heat, blood stasis) (P<0.05). The species abundance of the salivary microbiota was higher in the PN group than that in the HC group (P<0.05), and there was significant difference in community composition between the two groups (P<0.05). Correlation analysis using multiple methods, including Mantel test network heatmap analysis and Spearman correlation analysis and so on, the results showed that in the PN group, Prevotella and Porphyromonas were positively correlated with disease location in the lung, and Porphyromonas and Granulicatella were positively correlated with disease nature in yin deficiency (P<0.05). Conclusion The study concludes that there are notable differences in the distribution of TCM syndrome elements and the species abundance and composition of salivary microbiota between the patients with pulmonary nodules and the healthy individuals. The distinct external syndrome manifestations in patients with pulmonary nodules, compared to healthy individuals, may be a cascade event triggered by changes in the salivary microbiota. The dual correlation of Porphyromonas with both disease location and nature suggests that changes in its abundance may serve as an objective indicator for the improvement of symptoms in patients with yin deficiency-type pulmonary nodules.

Objective To construct a "disease-syndrome combination" mathematical representation model for pulmonary nodules based on oral microbiome data, utilizing a multimodal data algorithm framework centered on dynamic systems theory. Furthermore, to compare predictive models under various algorithmic frameworks and validate the efficacy of the optimal model in predicting the presence of pulmonary nodules. Methods A total of 213 subjects were prospectively enrolled from July 2022 to March 2023 at the Hospital of Chengdu University of Traditional Chinese Medicine, Sichuan Cancer Hospital, and the Chengdu Integrated Traditional Chinese and Western Medicine Hospital. This cohort included 173 patients with pulmonary nodules and 40 healthy subjects. A novel multimodal data algorithm framework centered on dynamic systems theory, termed VAEGANTF (Variational Auto Encoder-Generative Adversarial Network-Transformer), was proposed. Subsequently, based on a multi-dimensional integrated dataset of “clinical features-syndrome elements-microorganisms”, all subjects were divided into training (70%) and testing (30%) sets for model construction and efficacy testing, respectively. Using pulmonary nodules as dependent variables, and combining candidate markers such as clinical features, lesion location, disease nature, and microbial genera, the independent variables were screened based on variable importance ranking after identifying and addressing multicollinearity. Missing values were then imputed, and data were standardized. Eight machine learning algorithms were then employed to construct pulmonary nodule risk prediction models: random forest, least absolute shrinkage and selection operator (LASSO) regression, support vector machine, multilayer perceptron, eXtreme Gradient Boosting (XGBoost), VAE-ViT (Vision Transformer), GAN-ViT, and VAEGANTF. K-fold cross-validation was used for model parameter tuning and optimization. The efficacy of the eight predictive models was evaluated using confusion matrices and receiver operating characteristic (ROC) curves, and the optimal model was selected. Finally, goodness-of-fit testing and decision curve analysis (DCA) were performed to evaluate the optimal model. Results There were no statistically significant differences between the two groups in demographic characteristics such as age and sex. The 213 subjects were randomly divided into training and testing sets (7 : 3), and prediction models were constructed using the eight machine learning algorithms. After excluding potential problems such as multicollinearity, a total of 301 clinical feature information, syndrome elements, and microbial genera markers were included for model construction. The area under the curve (AUC) values of the random forest, LASSO regression, support vector machine, multilayer perceptron, and VAE-ViT models did not reach 0.85, indicating poor efficacy. The AUC values of the XGBoost, GAN-ViT, and VAEGANTF models all reached above 0.85, with the VAEGANTF model exhibiting the highest AUC value (AUC=0.923). Goodness-of-fit testing indicated good calibration ability of the VAEGANTF model, and decision curve analysis showed a high degree of clinical benefit. The nomogram results showed that age, sex, heart, lung, Qixu, blood stasis, dampness, Porphyromonas genus, Granulicatella genus, Neisseria genus, Haemophilus genus, and Actinobacillus genus could be used as predictors. Conclusion The “disease-syndrome combination” risk prediction model for pulmonary nodules based on the VAEGANTF algorithm framework, which incorporates multi-dimensional data features of “clinical features-syndrome elements-microorganisms”, demonstrates better performance compared to other machine learning algorithms and has certain reference value for early non-invasive diagnosis of pulmonary nodules.

Neuropathic pain(NP) has similar phenotypes but different sequential neuroinflammatory mechanisms in the pathological process. It is of great significance to inhibit the initiation of neuroinflammation, which has become a new direction of NP treatment and drug development in recent years. Mongolian drug Naru-3 is clinically effective in the treatment of trigeminal neuralgia, sciatica, and other NPs in a short time, but its pharmacodynamic characteristics and mechanism of analgesia are still unclear. In this study, a spinal nerve ligation(SNL) model simulating clinical peripheral nerve injury was established and the efficacy and mechanism of Naru-3 in the treatment of NPs was discussed by means of behavioral detection, side effect evaluation, network analysis, and experimental verification. Pharmacodynamic results showed that Naru-3 increased the basic pain sensitivity threshold(mechanical hyperalgesia and thermal radiation hyperalgesia) in the initiation of SNL in animals and relieved spontaneous pain, however, there was no significant effect on the basic pain sensitivity threshold and motor coordination function of normal animals under physiological and pathological conditions. Meanwhile, the results of primary screening of target tissues showed that Naru-3 inhibited the second phase of injury-induced nociceptive response of formalin test in mice and reduced the expression of inflammatory factors in the spinal cord. Network analysis discovered that Naru-3 had synergy in the treatment of NP, and its mechanism was associated with core targets such as matrix metalloproteinase-9(MMP9) and interleukin-1β(IL-1β). The experiment further took the dorsal root ganglion(DRG) and the stage of patho-logical spinal cord as the research objects, focusing on the core targets of inducing microglial neuroinflammation. By means of Western blot, immunofluorescence, agonists, antagonists, behavior, etc., the mechanism of Naru-3 in exerting NP analgesia may be related to the negative regulation of the MMP9/IL-1β signaling pathway-mediated microglia p38/IL-1β inflammatory loop in the activation phase. The relevant research enriches the biological connotation of Naru-3 in the treatment of NP and provides references for clinical rational drug use.
Rats ; Mice ; Animals ; Matrix Metalloproteinase 9/metabolism* ; Rats, Sprague-Dawley ; Neuroinflammatory Diseases ; Interleukin-1beta/metabolism* ; Spinal Cord/metabolism* ; Signal Transduction ; Hyperalgesia/metabolism* ; Neuralgia/metabolism*

Objective:To explore the difference of the vessel and plaque characteristics, myocardial perfusion and cardiac function between patients with ischemia with non-obstructive coronary artery disease (INOCA) and obstructive coronary artery disease (CAD).Methods:From July 2021 to June 2022, 101 patients with angina were referred to dynamic computed tomography myocardial perfusion (CTP) and coronary computed tomography angiography (CCTA) and retrospectively included in our hospital. Based on the results of CTP and CCTA, patients were divided into INOCA (27 cases), moderate obstructive CAD (26 cases) and severe obstructive CAD (48 cases). The anatomical coronary artery stenosis, plaque characteristics and myocardial perfusion features of all patients were analyzed. Furthermore, left ventricular global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) were obtained on full-phase reconstruction CCTA image by using Medis Suite 3.2 postprocessing software. Multigroup analysis used one way ANOVA or Kruskal Wallis H test. Results:Patients with INOCA were younger than patients with moderate and severe obstructive CAD ( P<0.001). INOCA patients (7.4%, 2/27) had lower rate of positive remodeling than both moderate (57.7%, 15/26, P<0.001) and severe obstructive CAD patients (33.3%, 16/48, P=0.017). The percentage of ischemic myocardium volume in patients with INOCA were similar with those in patients with severe CAD (all P>0.05), but significantly higher than those in patients with moderate CAD (all P<0.05). No significant difference in terms of GLS was detected between patients with INOCA [-17.4% (-21.6%, -11.6%)] and severe CAD [-17.6% (-21.9%, -14.8%), P=0.536], however, patients both with INOCA and severe CAD also had higher GLS than patients with moderate obstructive CAD [-22.3% (-29.8%, -19.0%), all P<0.05]. Conclusions:Based on"one-stop-shop"CTP combined with CCTA imaging, early cardiac functional changes including abnormal myocardial perfusion and myocardial strain in INOCA patients were similar to those in patients with severe obstructive CAD and more severe than those in patients with moderate obstructive CAD.

Objective: To investigate the clinicopathological features, diagnosis and differential diagnosis of breast myofibroblastoma. Methods: The clinicopathological data and prognostic information of 15 patients with breast myofibroblastoma diagnosed at the Department of Pathology of the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China from 2014 to 2022 were collected. Their clinical characteristics, histological subtypes, immunophenotypes and molecular characteristics were analyzed. Results: There were 12 female and 3 male patients, ranging in age from 18 to 78 years, with a median and average age of 52 years. There were 6 cases in the left breast and 9 cases in the right breast, including 12 cases in outer upper quadrant, 2 cases in inner upper quadrant and 1 case in outer lower quadrant. Most of the cases showed a well-defined nodule grossly, including pushing growth under the microscope in 13 cases, being completely separated from the surrounding breast tissue in 1 case, and infiltrating growth in 1 case. Among them, 12 cases were classic subtype and composed of occasional spindle cells with varying intervals of collagen fiber bundles; eight cases had a small amount of fat; one case had focal cartilage differentiation; one case was epithelioid subtype, in which epithelioid tumor cells were scattered in single filing or small clusters; one case was schwannoma-like subtype, and the tumor cells were arranged in a significant palisade shape, resembling schwannoma, and one case was invasive leiomyoma-like subtype, in which the tumor cells had eosinophilic cytoplasm and were arranged in bundles, and infiltrating into the surrounding mammary lobules like leiomyoma. Immunohistochemical studies showed that the tumor cells expressed desmin (14/15) and CD34 (14/15), as well as ER (15/15) and PR (15/15). Three cases with histologic subtypes of epithelioid subtype, schwannoma-like subtype and infiltrating leiomyoma-like subtype showed RB1 negative immunohistochemistry. Then FISH was performed to detect RB1/13q14 gene deletion, and identified RB1 gene deletion in all three cases. Fifteen cases were followed up for 2-100 months, and no recurrence was noted. Conclusions: Myofibroblastoma is a rare benign mesenchymal tumor of the breast. In addition to the classic type, there are many histological variants, among which the epithelioid subtype is easily confused with invasive lobular carcinoma. The schwannoma-like subtype is similar to schwannoma, while the invasive subtype is easily misdiagnosed as fibromatosis-like or spindle cell metaplastic carcinoma. Therefore, it is important to recognize the various histological subtypes and clinicopathological features of the tumor for making correct pathological diagnosis and rational clinical treatment.
Female ; Humans ; Male ; Antigens, CD34 ; Biomarkers, Tumor/analysis* ; Leiomyoma/pathology* ; Neoplasms, Muscle Tissue/pathology* ; Neurilemmoma ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Aged

OBJECTIVE: This study investigated the effects of bis (2-butoxyethyl) phthalate (BBOP) on the onset of male puberty by affecting Leydig cell development in rats. METHODS: Thirty 35-day-old male Sprague-Dawley rats were randomly allocated to five groups mg/kg bw per day that were gavaged for 21 days with BBOP at 0, 10, 100, 250, or 500 mg/kg bw per day. The hormone profiles; Leydig cell morphological metrics; mRNA and protein levels; oxidative stress; and AKT, mTOR, ERK1/2, and GSK3β pathways were assessed. RESULTS: BBOP at 250 and/or 500 mg/kg bw per day decreased serum testosterone, luteinizing hormone, and follicle-stimulating hormone levels mg/kg bw per day (P < 0.05). BBOP at 500 mg/kg bw per day decreased Leydig cell number mg/kg bw per day and downregulated Cyp11a1, Insl3, Hsd11b1, and Dhh in the testes, and Lhb and Fshb mRNAs in the pituitary gland (P < 0.05). The malondialdehyde content in the testis significantly increased, while Sod1 and Sod2 mRNAs were markedly down-regulated, by BBOP treatment at 250-500 mg/kg bw per day (P < 0.05). Furthermore, BBOP at 500 mg/kg bw per day decreased AKT1/AKT2, mTOR, and ERK1/2 phosphorylation, and GSK3β and SIRT1 levels mg/kg bw per day (P < 0.05). Finally, BBOP at 100 or 500 μmol/L induced ROS and apoptosis in Leydig cells after 24 h of treatment in vitro (P < 0.05). CONCLUSION: BBOP delays puberty onset by increasing oxidative stress and apoptosis in Leydig cells in rats. UNLABELLED The graphical abstract is available on the website www.besjournal.com.
Rats ; Male ; Animals ; Leydig Cells/metabolism* ; Testosterone ; Glycogen Synthase Kinase 3 beta/pharmacology* ; Rats, Sprague-Dawley ; Sexual Maturation ; Testis ; Oxidative Stress ; TOR Serine-Threonine Kinases/metabolism* ; Apoptosis

OBJECTIVES: To investigate the clinical treatment outcomes and the changes of the outcomes over time in extremely preterm twins in Guangdong Province, China. METHODS: A retrospective analysis was performed for 269 pairs of extremely preterm twins with a gestational age of <28 weeks who were admitted to the department of neonatology in 26 grade A tertiary hospitals in Guangdong Province from January 2008 to December 2017. According to the admission time, they were divided into two groups: 2008-2012 and 2013-2017. Besides, each pair of twins was divided into the heavier infant and the lighter infant subgroups according to birth weight. The perinatal data of mothers and hospitalization data of neonates were collected. The survival rate of twins and the incidence rate of complications were compared between the 2008-2012 and 2013-2017 groups. RESULTS: Compared with the 2008-2012 group, the 2013-2017 group (both the heavier infant and lighter infant subgroups) had lower incidence rates of severe asphyxia and smaller head circumference at birth (P<0.05). The mortality rates of both of the twins, the heavier infant of the twins, and the lighter infant of the twins were lower in the 2013-2017 group compared with the 2008-2012 group (P<0.05). Compared with the 2008-2012 group, the 2013-2017 group (both the heavier infant and lighter infant subgroups) had lower incidence rates of pulmonary hemorrhage, patent ductus arteriosus (PDA), periventricular-intraventricular hemorrhage (P-IVH), and neonatal respiratory distress syndrome (NRDS) and a higher incidence rate of bronchopulmonary dysplasia (P<0.05). CONCLUSIONS There is a significant increase in the survival rate over time in extremely preterm twins with a gestational age of <28 weeks in the 26 grade A tertiary hospitals in Guangdong Province. The incidences of severe asphyxia, pulmonary hemorrhage, PDA, P-IVH, and NRDS decrease in both the heavier and lighter infants of the twins, but the incidence of bronchopulmonary dysplasia increases. With the improvement of diagnosis and treatment, the multidisciplinary collaboration between different fields of fetal medicine including prenatal diagnosis, obstetrics, and neonatology is needed in the future to jointly develop management strategies for twin pregnancy.
Bronchopulmonary Dysplasia/epidemiology* ; Female ; Gestational Age ; Humans ; Infant ; Infant, Extremely Premature ; Infant, Newborn ; Pregnancy ; Respiratory Distress Syndrome, Newborn/epidemiology* ; Retrospective Studies ; Treatment Outcome

Background Air pollutants PM_2.5 and its adsorbed metal elements are important factors affecting public health. Objective To explore the distribution characteristics and sources of metal elements in atmospheric PM_2.5 in Lanzhou from 2019 to 2020, and to assess the health risks of metal elements to different groups of residents through inhalation. Methods From January 2019 to December 2020 in two districts of Lanzhou City (Chengguan District and Xigu District), regular PM_2.5 and metal elements [antimony (Sb), aluminum (Al), arsenic (As), beryllium (Be), cadmium (Cd), chromium (Cr), mercury (Hg), lead (Pb), manganese (Mn), nickel (Ni), selenium (Se), and thallium (Tl)] were regularly monitored, and their concentrations were described by the median (M) and 25^th and 75^th percentiles (P₂₅, P₇₅) as not following a normal distribution (because the detection rates of the five elements Be, Cr, Hg, Ni, and Se were less than 70%, the five elements were not included in subsequent analysis), and then compared with the secondary concentration limits in the Ambient Air Quality Standards (GB 3095-2012). The differences between the medians of the two groups were compared by the Mann-Whitney U rank sum test, and the differences among the medians of multiple groups were compared by the Kruskal-Wallis H rank sum test; the enrichment factor (EF) method and principal component analysis were used to evaluate the pollution degree of the metals and their sources; the health risks of five non-carcinogenic metals (Sb, Al, Pb, Mn, and Tl) and two carcinogenic metals (As and Cd) in PM_2.5 were evaluated by hazard index (HI) and hazard quotient (HQ) using the incremental lifetime cancer risk (LCR) model and the non-carcinogenic risk assessment model, respectively. Results The PM_2.5 concentrations [M (P₂₅, P₇₅)] in Lanzhou City were 38.50 (26.00, 65.00) and 41.00 (29.00, 63.10) μg·m⁻³ in 2019 and 2020, respectively, and the difference was not statistically significant (Z=−0.989, P > 0.05). The average levels of the metal elements from high to low were: Al > Pb > Mn > As > Cd > Sb > Tl, and the annual average concentration of each metal element in 2019 was higher than that in 2020 (P<0.05). The M ( P₂₅, P₇₅) of PM_2.5 concentrations in Chengguan and Xigu districts were 52.98 (17.00, 61.00) and 55.40 (17.00, 67.00) μg·m⁻³, respectively, with no statistically significant differences (P<0.05); the concentrations of Sb and Al in Chengguan District were lower than those in Xigu District (P<0.05), and the concentrations of other metal elements were not different between the two areas (P>0.05). There were seasonal differences in the concentrations of PM_2.5 and seven metal elements in Lanzhou City (except P_Al=0.007, the other P_s < 0.001). The results of the enrichment factor method showed that the EF values of the six metals (Sb, Al, As, Cd, Pb and Tl) were all greater than 1. Among them, except As, the EF values of other metal elements were all greater than 10, and the EF values of Al and Cd were both greater than 100. The results of principal component analysis showed that the variance contributions of the three principal components were 45.61%, 24.22%, and 14.42%, and the cumulative contribution reached 84.25%. The principal component 1 included Pb, As, Cd, and Sb, the principal component 2 included Al and Mn, and the principal component 3 contained Tl. The non-carcinogenic risks of the five metals were, in descending order, Al > Mn > Pb > Tl > Sb, among which the HQ values of the remaining four metals were less than 1 for adults and children, except the HQ value of Al for adults, which was greater than 1. The ILC values of carcinogenic metal As for adult males, adult females, and children were 2.68×10⁻⁵, 2.51×10⁻⁵, and 1.45×10⁻⁵, respectively; the ILC values of carcinogenic metal Cd for adult males, adult females, and children were 1.53×10⁻⁶, 1.43×10⁻⁶, and 8.26×10⁻⁷, respectively. Conclusion There is pollution of atmospheric PM_2.5 and its adsorbed metal elements in Lanzhou. As and Cd elements may pose potential carcinogenic risks to the residents.

Background Polycyclic aromatic hydrocarbons (PAHs) are one of the most widely distributed and harmful organic pollutants in the atmosphere. Objective To investigate the distribution characteristics and composition sources of PAHs in the atmosphere of two districts of Lanzhou from 2019 to 2020 and evaluate the health risks of PAHs via inhalation to different populations. Methods The PAHs concentrations in two urban areas (Chengguan District and Xigu District) of Lanzhou City from January 2019 to December 2020 were regularly monitored. Mann-Whitney U test was used to compare differences in target pollutant concentrations between the two areas. Diagnostic ratio method and principal component analysis were adopted for source identification. Incremental lifetime cancer risk (ILCR) model was applied to evaluate the health risks of PAHs. Results The M (P₂₅, P₇₅) PAHs concentrations in Chengguan District and Xigu District were 24.04 (14.59, 41.81) ng·m⁻³ and 25.97 (18.59, 42.56) ng·m⁻³, respectively, with no significant difference (Z=−0.970, P>0.05). As to seasonal distribution, most PAHs monomer concentrations in Chengguan District were higher than those in Xigu District in summer, and the concentrations of benzo[a]anthracene and benzo[g,h,i]perylene in Chengguan District were also higher than those in Xigu District in spring and autumn (P<0.05), but there were no significant differences in PAHs monomer concentrations between the two urban areas in winter (P>0.05). Ring number of PAHs exhibited seasonal fluctuations. In winter and spring, the highest proportions in Chengguan District and Xigu District were both 4-ring PAHs (37.32%-41.73%, 35.20%-39.66%), and in summer and autumn, the highest proportions were both 2- and 3-ring PAHs (39.38%-49.54%, 47.17%-51.23%). The results of diagnostic ratio method revealed mixed atmospheric PAHs sources in the two urban areas, including fossil fuel, coal, and biomass combustion. The results of principal component analysis showed that the cumulative contribution rate of the four principal component factors reached 79.54%. Principal component 1 included phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[a]pyrene; principal component 2 included acenaphthene and dibenzo[a,h]anthracene; principal component 3 was fluorene; principal component 4 was naphthalene. The results of health risk assessment showed that the ILCR values of adult males, adult females, and children in Chengguan District were 2.30×10⁻⁶, 2.16×10⁻⁶, and 1.73×10⁻⁶, respectively; and those in Xigu District were 1.58×10⁻⁶, 1.48×10⁻⁶, and 1.19×10⁻⁶, respectively; all were greater than 10⁻⁶. Conclusion PAHs pollution exists in the atmosphere of the two urban areas of Lanzhou City, mainly comes from mixed sources of fossil fuels, coal, and biomass burning, and may pose potential carcinogenic risks to the population.