To clarify the genetic diversity and structure of the nucleus population of F1-generation Litopenaeus vannamei, this study utilized 15 pairs of highly polymorphic microsatellite primers to analyze the simple sequence repeat (SSR) markers and genetic diversity in 15 full-sib families of L. vannamei. A total of 112 alleles (N_a) and 60.453 effective alleles (N_e) were identified among the selected 15 SSR loci, with the average polymorphic information content (PIC) of 0.648. The average N_e, observed heterozygosity (H_o), and expected heterozygosity (H_e) in the 15 F1 families varied from 1.925 to 2.626, 0.425 to 0.783, and 0.403 to 0.572, respectively. The 15 full-sib families were primarily clustered into three categories in the phylogenetic analysis, with the genetic distance between families ranging from 0.252 to 0.574. Additionally, the genetic differentiation coefficient (F_st) among the families varied from 0.112 to 0.278, indicating substantial genetic differentiation. Overall, this study suggested that the genetic diversity of the 15 full-sib families was moderate, providing valuable genetic insights for the subsequent breeding initiatives aimed at enhancing the tolerance of L. vannamei to high levels of soybean meal.
Penaeidae/classification* ; Microsatellite Repeats/genetics* ; Animals ; Genetic Variation ; Polymorphism, Genetic ; Phylogeny ; Alleles ; Genetic Markers

Objective To analyze result of the external quality assessment for laboratories of toxicological pathology diagnosis in organizations in China. Methods A total of 86 organizations that participated in the 2020-2021 external quality assessment in laboratory of toxicological pathology diagnosis (hereinafter referred to as "reference units") were selected as research subjects using convenient sampling method, and the assessment results were analyzed. Results The median of total score was 92, and the 0-100 percentiles were 64-100 in these 86 reference units. Among these reference units, 76 were rated as excellent, 10 as qualified, with the excellent and the qualified rate of 88.4% and 11.6%, respectively. No reference unit was rated as unqualified. The rates of excellence of the reference units in public health institutions, pharmaceutical research institutions, drug safety evaluation centers and testing companies were 95.7%, 84.2%, 85.7% and 86.7%, and the qualified rates were 4.3%, 15.8%, 14.3% and 13.3%, respectively. The distribution of excellence and qualification among the four types of reference units showed no statistical difference (P>0.05). The distribution of sample scores according to the three grades of poor, good, and excellent were 4.9%, 20.7%, and 74.5% in public health institutions, 8.6%, 23.7%, and 67.8% in pharmaceutical research institutions, 12.5%, 25.0%, and 62.5% in drug safety evaluation centers, and 5.4%, 17.5%, and 77.1% in testing companies. The proportion of excellence unit in public health institutions was higher than that in pharmaceutical research institutions (P<0.05). Conclusion The overall toxicological pathology diagnostic capabilities in China are good, and various types of reference units demonstrate comparable technical capabilities. However, there is a need for standardization of diagnostic terminology.

OBJECTIVE: To evaluate the diagnostic ability of toxicity pathology in patho-toxicological testing institutions in China. METHODS: The institutions participated in the 2018 Interlaboratory Comparison Activity of Toxicity Pathology Testing(hereinafter referred to as reference unit) were selected as the research subjects. The heart, spleen, skin, soft tissue, liver and mammary gland of SD rats of different groups in the 2-year carcinogenesis test were selected. The femur, knee joint and nose of Beagle dogs in the 4-week toxicity test and a total of 10 pathological tissues were selected as the comparison samples. The pathological diagnosis was carried out by the pathological diagnostic personnel of the reference unit, and the diagnostic results were reported. The expert appointed by the Toxicology and Pathology Committee of Chinese Toxicology Association compared the diagnostic results with the appointed value. RESULTS: A total of 167 pathological diagnostic personnel from 75 reference units in 24 provinces and municipalities participated in the comparison activity. The reference units were mainly distributed in East China, South China and North China, accounting for 77.3%(58/75). Totally 75 reference units fed back 750 effective diagnostic results. The qualified rates of diagnosis on heart, spleen, skin, soft tissue and breast samples were higher than 60.0%. The qualified rates of diagnosis on femur and knee joint, and nose samples were low(30.7% and 6.7%, respectively). There were 1(1.3%), 46(61.4%) and 28(37.3%) reference units rated as unqualified, qualified and excellent, respectively. CONCLUSION: Most of the testing institutions in China have a high level of patho-toxicological diagnostic ability, that can provide reliable diagnostic results for toxicology safety evaluation tests.

OBJECTIVE: To explore the non-neoplastic hepatic lesions in SD rats at different ages. METHODS: The specificpathogen free SD rats were collected from the blank control groups used in subacute toxicity tests,subchronic toxicity tests and chronic toxicity combined with carcinogenic tests for safety evaluation. At the end of each experiment,i. e. week 10,19,56 and 108(assigned into four groups: 10,19,56 and 108 weeks,each contained 100 rats with each sex),rats were executed. The liver organ coefficient was calculated,the pathological examination was performed,and the non-tumorous lesions in the liver were analyzed. RESULTS: The liver organ coefficients at the age of 19,56,108 weeks were lower than that of 10 weeks(P < 0. 05); those at the age of 56 and 108 weeks were lower than that of 19 weeks(P < 0. 05),and that of 108 weeks was greater than of 56 weeks(P < 0. 05). Among the 10-week-old,19-week-old,56-week-old and 108-week-old groups,the types of non-neoplastic hepatic lesions detected in the female rats were 6,6,13 and 15 respectively,meanwhile those in the male rats were 6,6,13 and 15 respectively. Both male and female rats,the incidences of hepatocyte fatty degeneration,edema and hepatic infiltration of inflammatory cells were significantly increased with the increase of age in each group(P < 0. 05). The incidences of intrahepatic bile duct proliferation and intrahepatic bile duct fibrosis in rats at the age of 56 and 108 weeks were higher than those at the age of 10 and 19 weeks(P < 0. 008).Moreover,the frequency of hepatic sinus expansion lesions in rats at the age of 108 weeks was higher than those of 19 weeks(P < 0. 008). CONCLUSION: Spontaneous non-neoplastic lesions in the liver of SD rats were common,primarily demonstrated as hepatocyte fatty degeneration,edema and infiltration of inflammatory cells. The incidences of lesions increased with the increase of age.

OBJECTIVE: To explore the spontaneous non-tumor lesion of kidney and its correlation with different age and sex in SD rats. METHODS: Eight hundred specific pathogen free SD rats were collected from the blank control groups used in subacute toxicity tests,subchronic toxicity tests and 1 or 2 years of chronic toxicity combined with carcinogenic tests. Rats were randomly divided into 4 groups with 10,19,56 or 108 weeks of experimental periods. Each group consisted of 100 female and 100 male rats. The renal tissues were collected at the end of each experiment,and the renal organ coefficients were calculated. The pathological non-tumor changes of the kidneys were analyzed. RESULTS: The renal organ coefficients in female rats at the age of 56 and 108 weeks were both lower than that of 10 and 19 weeks( P < 0. 008). The renal organ coefficient of male rats at the age of 56 weeks was lower than that of 10 and 19 weeks( P < 0. 008). The renal organ coefficient of male rats at the age of 108 weeks was higher than that of 56 weeks( P < 0. 008). The renal organ coefficient of male rats at the age of 108 weeks was higher than that of female rats of 108 weeks( P < 0. 008). The incidence of renal tubular calcium salt deposition,interstitial inflammatory cell infiltration and renal tubular dilatation in the female rats at the age of 108 weeks were higher than those in the male rats at the age of 108 weeks( P < 0. 05). The chronic progressive nephropathy incidence of female rats at the age of 108 weeks was lower than that of male rats aged 108 weeks( P < 0. 01).The renal tubular calcium salt deposition incidence of female rats aged 56 weeks was higher than that of male rats aged 56weeks( P < 0. 01). CONCLUSION: The spontaneous non-tumor lesions in the kidney of SD rats were common. The incidence of some lesions was different in the same age group with different sex.

OBJECTIVE: To observe the diagnostic capacity and its influencing factors in the toxicologic pathology diagnostic laboratories in China. METHODS: Inter-laboratory comparison of toxicologic pathology diagnosis was cosponsored by Chinese Society of Toxicology-Toxicologic Pathology Specialty Section and Guangdong Province Hospital for Occupational Disease Prevention and Treatment. Nine digital slices of digestive system lesions were screened as comparison samples,and the reference institution with toxicologic pathology diagnostic laboratories completed the diagnosis within the prescribed time. According to the three grades of “excellent”,“satisfaction”and “dissatisfaction”,the evaluation was carried out.RESULTS: A total of 74 reference institution participated in this comparison,which distributed in 20 provinces and 4 municipalities and 156 pathologists. The reference institutions were mainly distributed in North China,Southern China and East China. There was an average of 2 pathologists per laboratory,and in the quantity of academic title,the junior,intermediate,and senior was 15,70 and 46 persons respectively. Parasitic hepatocyte cysts( 97. 3%),adenocarcinoma of small intestine( 95. 9%) and polyarteritis nodosa of the pancreas( 89. 2%) had the highest rate of “excellent”grade,while the duodenal gland inflammation( 67. 6%),foam cell aggregation in colonic propria( 40. 5%) and hepatoma adenoma( 32. 4%) had the highest rate of dissatisfaction grade in the evaluation of single case. In the overall evaluation,reference laboratories reached the “excellent”grade and the “satisfaction”grade were 78. 4% and 21. 6% respectively.The number of pathologists provided by each reference laboratory had impacts on the overall evaluation level and the single case evaluation( neoplastic lesions) in the evaluation of single case( P < 0. 05). The types of the reference laboratory,the regional distribution and the grade of the academic title had no effect on the diagnostic ability( P > 0. 05). CONCLUSION: The reference laboratory is superior in diagnosing the digestive system lesions in the inter-laboratory comparison activity.The number of pathologists in the reference laboratory is one of the influencing factors of its diagnostic ability.

Objective To summarize the experiences of diagnosis and treatment for blunt tracheobronchial injuries ( BTI) . Methods From January 1993 to December 2013, 15 patients were diagnosed with BTI and underwent surgical treatment at our hospital.Mean age of the 15 patients (11 men and 4 women) was 26.4 ±4.5 years.All the patients had a history of trauma, which included crushing injury in 8 cases, deceleration injury in 4, fall injury in 2, and traction-type injury in 1.BTI loca-tion: right main bronchus in eight cases, left main bronchus in four cases, upper trachea in one case, lower trachea with the right main bronchus in one case, and cervico-thoracic trachea with left main bronchus in one case .Thoracic computerized tomo-graphy was performed in 15 patients, which showed pneumothorax, subcutaneous emphysema, pneumomediastinum or falling lung sign of Kumpe.Preoperative fiberoptic bronchoscopy examination was performed in 15 cases, which included bronchial atresia in 9 cases, bronchial transection in 3 cases, laceration of trachea in 2 cases, and tracheal transection in 1 case.An e-lective surgical procedure after BTI was performed in 10 cases, and emergency surgery was performed in 5 cases.Tracheo-bron-chial laceration repair were performed in 2 cases, tracheal end-to-end reanastomosis in 1 case, and bronchial end-to-end re-anastomosis in 12 cases.Results There was no operative death, and one case was complicated with anastomotic stenosis.The average operation time was 205.7 ±41.3 minutes, and the average blood loss was 268.4 ±109 ml.The postoperative hospi-tal stay was 11.6 ±3.7 days on average.Follow-up was completed in 15 patients (mean, 29.3 months), and 15 patients were all symptomatic improvement .Conclusion The most common site of BTI was the right main bronchus near Carina parts .Al-though the diagnosis and treatment are often delayed , our findings indicate that chest CT and endoscopic findings could be used for the diagnosis of BTI.Surgical resection and reconstruction are effective methods to repair BTI successfully even many months after they occur.Often they do not require the resection of pulmonary parenchyma .

BACKGROUND:Increasing attention has been paid on the role of advanced glycation end products in bone tissue. Glucose metabolic disorder is one of the main reasons for the increase of advanced glycation end products.
OBJECTIVE:To observe the change of advanced glycation end products expressed in type 2 diabetes rats, and to investigate the relationship between impaired fracture healing and change of advanced glycation end products expression in vivo.
METHODS:Thirty Sprague-Dawley rats were randomly and equal y divided into two groups:control group (normal feeding) and experimental group (high fat and sucrosum diet feeding to establish type 2 diabetes model). After diabetes models were established, the model of distraction osteogenesis in the left tibiae of al the rats was produced. Distraction was given 0.3 mm per day and continued for 14 days.
RESULTS AND CONCLUSION:After the traction was complete, cal us formation in distraction gap was obviously reduced in experimental group compared with control group by X-ray examination. The array of microcolumn formation was disordered and the area of primary matrix front was catachromasis by histology examination. The enzyme-linked immunosorbent assay results showed that, the level of advanced glycation end products was obviously elevated (P<0.01) while osteocalcin was obviously reduced (P<0.01) in experimental group in comparison with control group. The formation of distraction cal us was impaired in the process of fracture healing and blood of type 2 diabetes rats. The increase of advanced glycation end products may be one of the reasons that cause impaired fracture healing in diabetic rats.