Objective Three different doses of diethylnitrosamine(DEN)were used to establish a rat primary liver cancer(PLC)model to establish an efficient,stable,and economical animal model of PLC.Methods Forty-five male SD rats were randomly divided into four groups:normal group,DEN 50 mg/kg dose group(low dose group),70 mg/kg dose group(medium dose group),and 200 mg/kg dose group(high dose group).There were 6 animals in the normal group and 13 animals in each of the other groups.The normal control group received no treatment.The model group and low dose groups were injected intraperitoneally twice a week during weeks 1～4 and once a week during weeks 5～12;the medium dose group was injected intraperitoneally once a week for 16 consecutive weeks;and the high dose group was administered only once in the first week.The rats in each group were then followed for 16 weeks.The establishment of the model and optimal evaluation were verified by survival rate,pathological tests,biochemical tests,liver and spleen index calculation,immunohistochemistry,enzyme-linked immunosorbent assay(ELISA),and other assays.Results The survival rate was 100％in the normal group,46.15％in the low dose group,69.23％in the medium dose group,and 84.61％in the high dose group.The liver tissues of the rats in the normal group showed no abnormality to the naked eye;the liver of the rats in the low dose group became darker in color,rougher in surface,with a small number of cancerous nodules and slightly hard texture;the liver of the rats in the medium dose group was rough in surface,with several small cancerous nodules and scattered massive occupying nodules and hard texture;The liver of rats in the high dose group became lighter in color,slightly rougher in surface,with no obvious cancerous nodules;HE staining showed that the liver tissues of rats in the low and medium dose groups were structurally disorganized,with large cellular heterogeneity and tumor cells.HE staining showed that the liver tissues of rats in the low and medium dose groups were structurally disorganized,with large cellular heterogeneity and tumor cell formation,while the structure of the liver lobules of the high dose group was unclear,with different degrees of edema,degeneration and necrosis of liver cells,and no obvious tumor cell formation was seen.Compared with the normal group,serum liver function alanine aminotransferase(ALT),aspartate aminotransferase(AST),and total bilirubin(TBIL)were elevated in the low,medium,and high dose groups;ALT and AST were significantly elevated in the low dose group(P<0.05),the difference was statistically significant,ALT,AST and TBIL were significantly elevated in the medium dose group(P<0.05),the difference was statistically significant,and the difference was statistically significant,although liver function in the high dose group was elevated,he increase was not significant,the difference was not statistically significant(P>0.05);compared with the normal group,the international normalized ratio(INR)of coagulation function was significantly higher in the low dose group,with a statistically significant difference(P<0.05),and the activated partial thromboplastin time(APTT),prothrombin time(PT),and alpha-fetoprotein(AFP)levels were increased(P<0.05),and the difference was not statistically significant;serum APTT,PT,INR,and AFP levels were significantly increased in the medium dose group(P<0.05),and the difference was statistically significant;serum PT and AFP levels were increased in the high dose group(P<0.05),the difference was statistically significant,and plasma APTT levels were slightly increased(P>0.05),the difference was not statistically significant;liver and spleen indexes were increased in the medium dose group(P<0.05),the spleen index increased in the low dose group(P<0.05),and the liver index increased in the high dose group(P<0.05),the difference was statistically significant;the optical density value of liver tissue AFP increased significantly in the low,medium and high dose groups(P<0.05),the difference was statistically significant.Conclusions Both the low and medium dose groups could successfully induce the PLC rat model,but the pathological changes and biochemical findings of the medium dose group were more consistent with the pathogenesis of human liver tissue from liver injury to hepatic fibrosis to cirrhosis to hepatocellular carcinoma,and the number of administrations of the drug is less,and the survival rate of the rats is higher so that a more cost-effective and superior PLC model can be established.

The 2025 Edition of the Pharmacopoeia of the People's Republic of China added the physical performance evaluation method of metallic metered dose inhalation(MDI)canister and related standards.The relevant physical performance evaluation methods are of great significance to the quality control of metallic inhalation canister,which is an important basis for the evaluation of drug protection ability,and also fills the blank of the physical performance evaluation method of metallic cans for drug packaging.It can scientifically and effectively guide the drug packaging material production enterprises to carry out standardized and unified quality control of metallic MDI inhalation canister,play a role in the quality control of metallic MDI inhalation canister,and ensure the safety,effectiveness,and accessibility of drugs in the whole life cycle.By comparing the domestic and international standards of metallic canister,this document mainly analyzed the detection principle,method points and its role in drug packaging quality control of pressure resistance performance、internal coating continuity,oxide film thickness,coating surface energy and coating contact angle,to help all parties more effectively and fully understand,master and apply the physical performance evaluation methods of the metallic MDI inhalation canister and relevant standards in the 2025 Edition of the Pharmacopoeia of the People's Republic of China,and provide theoretical guidance and technical support for the implementation of the standard.

To analyze the standard establishment approach and compilation rationale for metallic pharmaceutical packaging standard development in the 2025 edition of the Pharmacopeia of the People's Republic of China.This article systematically explained the background and process of establishing the guiding principles for metallic materials and containers used in pharmaceutical packaging in the Chinese Pharmacopoeia through basic information,relevant domestic and international standards,the establishment of key quality attributes of metallic pharmaceutical packaging materials,and the construction of metallic pharmaceutical packaging material standards.The newly established guidelines,the Pharmacopeia of the People's Republic of China 9625,prioritized product critical quality attributes(CQAs)and real-world applicability.This dual emphasis on rigidity and adaptability enhances drug safety,meets the regulatory requirements,and promotes the globalization and scientific advancement of China's pharmaceutical packaging industry.

The 2025 Edition of the Pharmacopoeia of the People's Republic of China added the physical performance evaluation method of metallic metered dose inhalation(MDI)canister and related standards.The relevant physical performance evaluation methods are of great significance to the quality control of metallic inhalation canister,which is an important basis for the evaluation of drug protection ability,and also fills the blank of the physical performance evaluation method of metallic cans for drug packaging.It can scientifically and effectively guide the drug packaging material production enterprises to carry out standardized and unified quality control of metallic MDI inhalation canister,play a role in the quality control of metallic MDI inhalation canister,and ensure the safety,effectiveness,and accessibility of drugs in the whole life cycle.By comparing the domestic and international standards of metallic canister,this document mainly analyzed the detection principle,method points and its role in drug packaging quality control of pressure resistance performance、internal coating continuity,oxide film thickness,coating surface energy and coating contact angle,to help all parties more effectively and fully understand,master and apply the physical performance evaluation methods of the metallic MDI inhalation canister and relevant standards in the 2025 Edition of the Pharmacopoeia of the People's Republic of China,and provide theoretical guidance and technical support for the implementation of the standard.

To analyze the standard establishment approach and compilation rationale for metallic pharmaceutical packaging standard development in the 2025 edition of the Pharmacopeia of the People's Republic of China.This article systematically explained the background and process of establishing the guiding principles for metallic materials and containers used in pharmaceutical packaging in the Chinese Pharmacopoeia through basic information,relevant domestic and international standards,the establishment of key quality attributes of metallic pharmaceutical packaging materials,and the construction of metallic pharmaceutical packaging material standards.The newly established guidelines,the Pharmacopeia of the People's Republic of China 9625,prioritized product critical quality attributes(CQAs)and real-world applicability.This dual emphasis on rigidity and adaptability enhances drug safety,meets the regulatory requirements,and promotes the globalization and scientific advancement of China's pharmaceutical packaging industry.

Objective Three different doses of diethylnitrosamine(DEN)were used to establish a rat primary liver cancer(PLC)model to establish an efficient,stable,and economical animal model of PLC.Methods Forty-five male SD rats were randomly divided into four groups:normal group,DEN 50 mg/kg dose group(low dose group),70 mg/kg dose group(medium dose group),and 200 mg/kg dose group(high dose group).There were 6 animals in the normal group and 13 animals in each of the other groups.The normal control group received no treatment.The model group and low dose groups were injected intraperitoneally twice a week during weeks 1～4 and once a week during weeks 5～12;the medium dose group was injected intraperitoneally once a week for 16 consecutive weeks;and the high dose group was administered only once in the first week.The rats in each group were then followed for 16 weeks.The establishment of the model and optimal evaluation were verified by survival rate,pathological tests,biochemical tests,liver and spleen index calculation,immunohistochemistry,enzyme-linked immunosorbent assay(ELISA),and other assays.Results The survival rate was 100％in the normal group,46.15％in the low dose group,69.23％in the medium dose group,and 84.61％in the high dose group.The liver tissues of the rats in the normal group showed no abnormality to the naked eye;the liver of the rats in the low dose group became darker in color,rougher in surface,with a small number of cancerous nodules and slightly hard texture;the liver of the rats in the medium dose group was rough in surface,with several small cancerous nodules and scattered massive occupying nodules and hard texture;The liver of rats in the high dose group became lighter in color,slightly rougher in surface,with no obvious cancerous nodules;HE staining showed that the liver tissues of rats in the low and medium dose groups were structurally disorganized,with large cellular heterogeneity and tumor cells.HE staining showed that the liver tissues of rats in the low and medium dose groups were structurally disorganized,with large cellular heterogeneity and tumor cell formation,while the structure of the liver lobules of the high dose group was unclear,with different degrees of edema,degeneration and necrosis of liver cells,and no obvious tumor cell formation was seen.Compared with the normal group,serum liver function alanine aminotransferase(ALT),aspartate aminotransferase(AST),and total bilirubin(TBIL)were elevated in the low,medium,and high dose groups;ALT and AST were significantly elevated in the low dose group(P<0.05),the difference was statistically significant,ALT,AST and TBIL were significantly elevated in the medium dose group(P<0.05),the difference was statistically significant,and the difference was statistically significant,although liver function in the high dose group was elevated,he increase was not significant,the difference was not statistically significant(P>0.05);compared with the normal group,the international normalized ratio(INR)of coagulation function was significantly higher in the low dose group,with a statistically significant difference(P<0.05),and the activated partial thromboplastin time(APTT),prothrombin time(PT),and alpha-fetoprotein(AFP)levels were increased(P<0.05),and the difference was not statistically significant;serum APTT,PT,INR,and AFP levels were significantly increased in the medium dose group(P<0.05),and the difference was statistically significant;serum PT and AFP levels were increased in the high dose group(P<0.05),the difference was statistically significant,and plasma APTT levels were slightly increased(P>0.05),the difference was not statistically significant;liver and spleen indexes were increased in the medium dose group(P<0.05),the spleen index increased in the low dose group(P<0.05),and the liver index increased in the high dose group(P<0.05),the difference was statistically significant;the optical density value of liver tissue AFP increased significantly in the low,medium and high dose groups(P<0.05),the difference was statistically significant.Conclusions Both the low and medium dose groups could successfully induce the PLC rat model,but the pathological changes and biochemical findings of the medium dose group were more consistent with the pathogenesis of human liver tissue from liver injury to hepatic fibrosis to cirrhosis to hepatocellular carcinoma,and the number of administrations of the drug is less,and the survival rate of the rats is higher so that a more cost-effective and superior PLC model can be established.

Objective To prepare a stable rat model of chronic liver failure to provide a tool for basic research.Methods Sixty-six SPF SD rats were divided into a normal group(n=18)and a modeling group(n=48).Rats in the modeling group received an intraperitoneal injection of 50％CCl4 olive oil solution(1.5 mL/kg,twice a week).Multidimensional assessment was performed at 8,16,and 24 weeks,respectively,including ultrasonic examination of liver morphology,hardness,portal vein diameter,and ascites,and collection of serum,plasma,and liver tissue to detect liver function,coagulation function,and blood ammonia levels.Liver tissue injury and fibrosis were observed by hematoxylin-eosin(HE)and Masson staining.Cognitive function was assessed using the water maze test.Survival were recorded simultaneously.Results Rats in the model group showed decreased activity and appetite,yellow urine,and increased abdominal circumference compared with the normal group.Ultrasound showed enhanced liver parenchyma echo in the model group that thickened with time,secondary ascites formation,portal vein dilation,and portal hypertension.Water maze and blood ammonia tests confirmed cognitive decline(memory and orientation loss)and hepatic encephalopathy in the model group.Gross observation showed that the liver in the model group was atrophied and appeared rough and uneven.HE staining showed hepatocyte swelling,steatosis,and necrosis,and Masson staining confirmed fibrosis progression with pseudolobule formation.The liver function indexes AST,ALT,TBIL and blood ammonia continued to increase,and coagulation dysfunction(prolonged PT and increased INR)gradually increased with the modeling process.Conclusions Intraperitoneal injection of 50％CCl4 olive oil solution(1.5 mL/kg,every week)for 24 weeks can stably simulate persistent chronic liver injury in rats and lead to the typical pathological changes and complications of chronic liver failure,based on the decompensation stage of cirrhosis.This model replicates the pathological evolution of human hepatitis from liver fibrosis → liver cirrhosis compensation → decompensation → chronic liver failure,providing a reliable modeling reference for the study of the mechanism of chronic liver failure.

Objective To prepare a stable rat model of chronic liver failure to provide a tool for basic research.Methods Sixty-six SPF SD rats were divided into a normal group(n=18)and a modeling group(n=48).Rats in the modeling group received an intraperitoneal injection of 50％CCl4 olive oil solution(1.5 mL/kg,twice a week).Multidimensional assessment was performed at 8,16,and 24 weeks,respectively,including ultrasonic examination of liver morphology,hardness,portal vein diameter,and ascites,and collection of serum,plasma,and liver tissue to detect liver function,coagulation function,and blood ammonia levels.Liver tissue injury and fibrosis were observed by hematoxylin-eosin(HE)and Masson staining.Cognitive function was assessed using the water maze test.Survival were recorded simultaneously.Results Rats in the model group showed decreased activity and appetite,yellow urine,and increased abdominal circumference compared with the normal group.Ultrasound showed enhanced liver parenchyma echo in the model group that thickened with time,secondary ascites formation,portal vein dilation,and portal hypertension.Water maze and blood ammonia tests confirmed cognitive decline(memory and orientation loss)and hepatic encephalopathy in the model group.Gross observation showed that the liver in the model group was atrophied and appeared rough and uneven.HE staining showed hepatocyte swelling,steatosis,and necrosis,and Masson staining confirmed fibrosis progression with pseudolobule formation.The liver function indexes AST,ALT,TBIL and blood ammonia continued to increase,and coagulation dysfunction(prolonged PT and increased INR)gradually increased with the modeling process.Conclusions Intraperitoneal injection of 50％CCl4 olive oil solution(1.5 mL/kg,every week)for 24 weeks can stably simulate persistent chronic liver injury in rats and lead to the typical pathological changes and complications of chronic liver failure,based on the decompensation stage of cirrhosis.This model replicates the pathological evolution of human hepatitis from liver fibrosis → liver cirrhosis compensation → decompensation → chronic liver failure,providing a reliable modeling reference for the study of the mechanism of chronic liver failure.

With the development of computer science and dental materials,digital technology is progressively changing the way of clinical work of dentistry.As a digital processing method,3D printing plays an important role in the manufacture of restorations,and the basic process includes vat photopolymerization,material jetting,material extrusion,etc.Among them,desktop printing devices based on the principle of vat photopolymerization are most widely used in dental clinical work because of their high printing accuracy and fast molding speed.This paper briefly introduces the principles of vat photopolymerization technology used in clinical work,the materials and the workflow of the printer,and provides a review of the application of vat photopolymerization technology in the field of restorative dentistry.

Objective:To compare and analyze the distribution characteristics of fluoride and arsenic in drinking water in coal-burning borne endemic fluorosis and arsenic poisoning areas and non-endemic areas of Guizhou Province, and to assess the health risk.Methods:From January 2018 to December 2019, drinking water samples were collected from all endemic and non-endemic townships in 37 coal-burning borne endemic fluorosis counties (cities and districts) and 4 coal-burning borne endemic arsenic poisoning counties (cities and districts) in Guizhou Province. Fluoride and arsenic levels in drinking water were determined in all the affected and non-affected townships. Among them, 3 800 water samples were collected from fluorosis areas, 1 445 water samples from non-endemic areas, and 117 water samples from arsenic poisoning areas and non-endemic areas, respectively. Based on Monte Carlo simulation, a health risk assessment model recommended by the US Environmental Protection Agency (EPA) was applied to quantitatively evaluate the health risks caused by fluoride and arsenic in drinking water in different regions through different pathways (drinking water intake or skin contact) to different populations (adult males, adult females and children).Results:According to the "Hygienic Standards for Drinking Water" (GB 5749-2022), the qualified rates of fluoride and arsenic levels in drinking water in the study area were 100%. The results of the health risk evaluation showed that in the same evaluation area (endemic area or non-endemic area), there were statistically significant differences in the average annual health risks caused by fluoride and arsenic exposure through drinking water among different populations through two different routes ( P < 0.001), with children's health risks > adult males > adult females ( P < 0.05). The average annual health risks of fluoride and arsenic in water samples from different water periods and source types were compared via the two exposure routes, and the differences were statistically significant ( P < 0.05). At high ( P95) and moderate ( P50) exposure levels, the average annual total health risks of fluoride in drinking water via the two exposure routes (drinking water intake and skin contact) for adult males, adult females, children and the general population in fluorosis areas were a -1: 2.50 × 10 -9 and 8.64 × 10 -10, 2.20 × 10 -9 and 7.61 × 10 -10, 3.00 × 10 -9 and 1.04 × 10 -9, 2.36 × 10 -9 and 8.15 × 10 -10, respectively, and a -1: 2.44 × 10 -9 and 6.92 × 10 -10, 2.15 × 10 -9 and 6.09 × 10 -10, 2.93 × 10 -9 and 8.32 × 10 -10, 2.30 × 10 -9 and 6.53 × 10 -10 in non-endemic areas, respectively; the average annual total health risks of adult males, adult females, children, and the general population caused by arsenic ingestion through drinking water and skin contact in arsenic poisoning areas were a -1: 9.10 × 10 -7 and 3.67 × 10 -7, 8.11 × 10 -7 and 3.22 × 10 -7, 1.13 × 10 -6 and 4.45 × 10 -7, 8.95 × 10 -7 and 3.47 × 10 -7, respectively, and a -1: 2.42 × 10 -6 and 5.61 × 10 -7, 2.11 × 10 -6 and 4.80 × 10 -7, 2.88 × 10 -6 and 6.55 × 10 -7, 2.21 × 10 -6 and 5.25 × 10 -7 in non-endemic areas, respectively; average annual total health risks of adult males, adult females, children and the general population were all in the safe range [fluoride in drinking water: negligible levels recommended by the Royal Society and the Dutch Ministry of Construction and Environment were 1.0 × 10 -7 a -1 and 1.0 × 10 -8 a -1, respectively; arsenic in drinking water: the maximum acceptable level recommended by the International Commission on Radiological Protection (ICRP) was 5.0 × 10 -5 a -1]. Conclusions:The fluoride and arsenic levels in the drinking water of coal-burning borne endemic fluorosis and arsenic poisoning areas and non-endemic areas in Guizhou Province meet the requirements of hygienic standards for drinking water; the overall health risks of fluoride and arsenic to people of different ages and genders ingested through drinking water and through skin contact are within an acceptable range.