[Clinical outcome of combined over-the-top reconstruction with modified Lemaire procedure in one-stage revision anterior cruciate ligament reconstruction]

Objective: To investigate the clinical effect of over-the-top (OTT) reconstruction of the anterior cruciate ligament (ACL) combined with the modified Lemaire technique in one-stage ACL revision. Methods: It's a retrospective study. The clinical data of 37 patients who underwent one-stage revision of ACL using OTT combined with modified Lemaire technique from April 2020 to May 2023 in the Department of Sports Medicine of Xinhua Hospital Affiliated to Dalian University were retrospectively analyzed. There were 28 males and 9 females with a mean age of (32.7±5.7) years. The postoperative knee function and surgical revision effect were evaluated by subjective and objective evaluation indexes of the knee joint before and 3 months and 24 months after surgery. The subjective evaluation indexes included the International Knee Documentation Committee (IKDC) score, Lysholm score, and Tegner score; and the objective evaluation indexes included the anterior-posterior static displacement distance of the tibia, tibia-femur relative rotation angle, the Lachman test, the axial shift test, and the ratio of the loss of muscle strength of the lower limb. Results: At the final follow-up, all patients returned to pre-injury motor level, with significant improvements in IKDC scores (45.3±6.8 preoperatively, 67.5±4.7 and 93.2±2.3 at 3 months and 2 years after the operation, respectively), Lysholm scores (57.2±2.6 preoperatively, 72.6±2.9 and 89.7±3.7 at 3 months and 2 years after the operation, respectively), and Tegner scores (3.1±0.7 preoperatively, 4.9±0.6 and 5.8±1.3 at 3 months and 2 years after the operation, respectively) (all P<0.001). The anterior-posterior static displacement distance of the tibia reduced significantly [from (5.2±0.5) mm before the operation to (1.4±0.5) mm at 2 years postoperatively) (P<0.001)]; and the relative rotation angle of the tibia-femur restored to the normal physiological range, it was reduced from 6.2°±1.2° before the operation to 1.7°±0.3° 2 years after (P<0.001). The Lachman test and axial shift test at 2 years postoperatively were all negative. The muscle strength loss ratio of the affected lower limb was significantly better than that before the operation (P<0.001). Conclusion: The use of OTT reconstruction combined with modified Lemaire technique for revision of ACL in patients with ACL reconstruction failure can circumvent the tunnel problem for one-stage revision and better restore the stability and function of the knee joint, with ideal clinical results.

[Association between HULC gene locus rs7763881 polymorphism and recurrence and metastasis after radical resection in hepatocellular carcinoma]

Objective: To investigate the association between the expression of long non-coding RNA genes and the HULC rs7763881 polymorphism, recurrence, and metastasis after radical resection in patients with hepatocellular carcinoma (HCC). Methods: Paraffin tissue samples were selected from 426 cases diagnosed with HCC between January 2004 to January 2012. The expression of different genotypes of HULC gene locus rs7763881 in paraffin tissues was detected by PCR, and the association between different genotype expressions and clinical case characteristics of HCC [gender, age, TNM stage, alpha-fetoprotein, tumor maximum diameter (cm), vascular invasion, tumor capsule, tumor grade] was analyzed. Cox proportional risk regression model was used to analyze the correlation between different genotypes and clinicopathological features, prognosis, and recurrence. Survival analysis between different genotypes was performed using the Kaplan-Meier method for a parallel log-rank test. Results: There were 27 (6.3%) cases in the whole group who lost to follow-up. A total of 399 (93.7%) specimens were included in the study, and 105 (26.3%), 211 (52.9%) and 83 (20.8%) were included in the rs77638881 AA, AC, and CC genotypes, respectively. Kaplan-Meier curve showed that the postoperative overall survival and recurrence-free survival rate were significantly higher in patients with the AA than AC/CC genotype (P < 0.05). Univariate analysis showed that the AC/CC genotype was closely related to tumor vascular invasion and recurrence or metastasis of HCC (P < 0.05). Cox multivariate analysis results showed that patients with the AA genotype were taken as references, and the results showed that the risk of recurrence and metastasis in patients with the CA/CC genotype increased to varying degrees, with statistical significance (P < 0.05). Conclusion: The rs7763881 polymorphic loci located on the HULC gene are closely related to HCC recurrence and metastasis after radical resection. Thus, it may be an indicator for evaluating HCC recurrence and metastasis.

Socio-economic inequalities in health among older adults in China

OBJECTIVES

This study aimed to explore socio-economic inequalities in the health status of older people in China using the most recent data available.

STUDY DESIGN

This was a cross-sectional study.

METHODS

Data for this study were obtained from the 2018 China Health and Retirement Longitudinal Study, which included 9831 subjects aged 60 years and older. We assessed differences in the prevalence of self-reported health, functional limitations, and chronic conditions by education level and household income level, and then estimated the Slope of Inequality Index (SII) and the Relative Inequality Index (RII) - indexes of the relative magnitude of socio-economic inequalities in health.

RESULTS

We found inequalities in all dimensions of health (self-assessed health status, reported chronic conditions, and physical functional limitations) at the household income level. Physical functional limitations, particularly the ability to perform instrumental activities of daily living, produced greater inequality than other domains, with an adjusted SII of 0.495 (95% CI, 0.467-0.524) and an adjusted RII of 2.129 (95% CI, 1.604-2.653). ADL limitations (adjusted SII, 0.524, 95% CI, 0.473-0.575, adjusted RII, 1.527, 95% CI, 1.027-2.027) and self-measured health (adjusted SII, 0.523, 95% CI, 0.258-0.789, adjusted RII, 1.531, 95% CI, 0.551-2.512) were also clearly different. Inequalities were also found across all health domains in terms of educational attainment. Consistent with inequalities in household income, inequalities were greatest for limitations in the ability to perform instrumental activities of daily living (adjusted SII, 0.581, 95% CI, 0.424-0.739, adjusted RII, 3.699, 95% CI, 3.642-3.757). Relative inequalities in limitations in activities of daily living (adjusted SII, 0.676, 95% CI, 0.560-0.792, adjusted RII, 2.587, 95% CI, 2.392-2.784) and self-rated health (poor/very poor) (adjusted SII, 0.647, 95% CI, 0.617-0.677, adjusted RII, 2.406, 95% CI, 2.224-2.587) were also higher.

CONCLUSION

Our study shows significant socio-economic differences in the areas of self-rated health, functional limitations, and reported chronic diseases, particularly in the area of IADL limitations. These inequalities need to be explicitly addressed and vulnerable subgroups should be targeted to reduce the socio-economic disparities.

[The diagnostic value of machine-learning-based model for predicting the malignancy of solid nodules in multiple pulmonary nodules]

Objective: To examine the efficiacy of a machine learning diagnostic model specifically for solid nodules in multiple pulmonary nodules constructed by combining patient clinical information and CT features. Methods: Totally 446 solid nodules resected from 287 patients with multiple pulmonary nodules in Department of Thoracic Surgery, Peking University People's Hospital from January 2010 to December 2018 were included. There were 117 males and 170 females, aging (61.4±9.9) yeras (range: 33 to 84 years). The nodules were randomly divided into training set (228 patients with 357 nodules) and test set (59 patients with 89 nodules) by a ratio of 4∶1. The extreme gradient boosting (XGBoost) algorithm was used to generate a predictive model (PKU-ML model) on the training set. The accuracy was verified on the test set and compared with previous published models. Finally, an independent single solid nodule set (155 patients, 95 males, aging (62.3±8.3) years (range: 37 to 77 years)) was used to evaluate the accuracy of the model for predictive value of single solid nodules. Area of receiver operating characteristic curve (AUC) was used to evaluate diagnostic values of models. Results: In the training set, the AUC of the PKU-ML model was 0.883 (95%CI: 0.849 to 0.917). In the test set, the performance of the PKU-ML model (AUC=0.838, 95%CI: 0.754 to 0.921) was better than the models designed for single pulmonary nodules (Brock model: AUC=0.709, 95%CI: 0.603 to 0.816, P=0.04; Mayo model: AUC=0.756, 95%CI: 0.656 to 0.856, P=0.01; VA model: AUC=0.674, 95%CI: 0.561 to 0.787, P<0.01), similar with PKUPH model (AUC=0.750, 95%CI: 0.649 to 0.851, P=0.07). In the independent single solid nodules set, the PKU-ML model also achieved good performance (AUC=0.786, 95%CI: 0.701 to 0.872). Conclusion: The machine learning based PKU-ML model can better predict the malignancy of solid nodules in multiple pulmonary nodules, and also achieved a good performance in predicting the malignancy of single solid pulmonary nodules compared to mathematical models.

[The multi-dimensional molecular characteristics of the indolent pulmonary ground-glass nodules]

With the dramatically increasing detection rate of ground-glass nodules (GGN), exact understanding and treatment strategy of them has become the hottest issue currently. More and more studies have begun to explore the underlying mechanisms of their indolent characteristics and favorable prognosis from the perspectives of molecular evolution and immune microenvironment. GGN has different dominating gene mutations at different evolutional stages. The pure GGN has a lower tumor mutation burden and genomic instability, while a gradually evolutionary feature of genomic mutation along with the pathological progression can be observed. GGN has less infiltration of immune cells, and they are under the pressure of immune surveillance with weakened immune escape. With the increase of solid components, an inhibitory immune microenvironment is gradually established and immune escape is gradually enhanced, leading to rapid tumor growth. Further exploration of the molecular characteristics of GGN will help to more precisely distinguish these highly heterogeneous lesions, which could be helpful to make personalized treatment plans.

[The association between serum total homocysteine and subacute combined degeneration of spinal cord]

Objective: The research was aimed to investigate the association between serum total homocysteine (tHcy) and subacute combined degeneration of the spinal cord (SCD). Methods: A retrospective survey of 106 newly diagnosed patients with SCD were enrolled in this research who were treated in the department of neurology of Xijing Hospital from January 2008 to February 2019, meanwhile, 121 patients with spinal cord lesion (not SCD) and 104 neurology mild outpatients were selected as controls. Serum tHcy level was determined by using the chemiluminescent immunoassay assay. A multivariate logistic regression model was used to analyze the risk factors for SCD. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve, sensitivity, specificity and Youden index were used to evaluate the diagnostic efficacy of tHcy. Spearman correlation analysis was used to observe the correlation between tHcy and SCD severity. The SCD patients were categorized into normal or mild tHcy group, moderate tHcy group, and severe tHcy group based on tHcy levels. Clinical symptoms, nerve conduction velocity, magnetic resonance imaging (MRI) findings from the patients were studied. Results: The serum tHcy levels in SCD patients were 64.3(26.5, 98.8) μmol/L, while in patients with spinal cord lesion (not SCD) group were 13.7(10.8, 19.2) μmol/L, neurology mild outpatients were 10.6(8.2, 13.0) μmol/L, which was higher in SCD group (H=112.020,P<0.001), (H=165.525,P<0.001).The multivariate logistic regression model showed tHcy is the impact factor of SCD (OR=1.107, 95%CI:1.077-1.139, P<0.001). At ROC analysis, tHcy showed diagnostic value with an optimal cut-off value of 24.9 μmol/L (AUC 0.913, 95%CI: 0.875-0.951, sensitivity 79.2%, specificity 91.6%). Spearman correlation analysis showed that tHcy was positively correlated with functional disability rating scale (r=0.254, P=0.009). Conclusions: Serum tHcy is the risk factor for SCD and related to its disability. Focus on the increased level of tHcy plays a positive role in the diagnosis of SCD.

[Correlation among age, sex, and liver diseases-related mortality risk in patients with hepatitis B virus-related liver cirrhosis]

Objective: To understand and compare the differences between age, sex and liver diseases-related mortality risk in patients with hepatitis B virus-related liver cirrhosis. Methods: Based on the front-page inpatient medical record database and the death registration system of Beijing patients with hepatitis B-related liver cirrhosis from 2008 to 2015 were included. The survival information of all patients were traced up to the occurrence of liver disease-related mortality event or until December 31, 2019. Kaplan-Meier method was used to calculate the cumulative incidence of liver disease-related mortality in patients with liver cirrhosis. Cox regression model was used to analyze the effect of age-gender interaction on liver disease-related mortality risk. Results: A total of 16 738 patients with hepatitis B-related liver cirrhosis were included, of which 13 969 cases (83.46%) were in compensated stage and 2 769 cases (16.54%) were in decompensated stage. Liver cirrhosis complications mortality risk in patients with compensated stage cirrhosis at 3, 5, and 8 years were 10.84%, 12.70%, and 14.37%, respectively; while in decompensated stage patients, the mortality risk was 16.70%, 19.02%, and 20.73%, respectively. The 3, 5, and 8-year liver cancer mortality rates of patients with compensated stage liver cirrhosis were 5.24%, 7.49%, and 10.25%, respectively; while those with decompensated stage liver cancer mortality rates were 9.01%, 11.16%, and 13.50%, respectively. Liver disease-related mortality risk was increased with age in patients with liver cirrhosis. Liver cirrhosis complications mortality risk in female patients with liver cirrhosis at age < 60 years was lower than that of male patients. Liver cirrhosis complications mortality risk in male and female patients aged 60-69 years were similar. Liver cirrhosis complications mortality risk in female patients aged ≥70 years was higher than that of male patients. However, female patients had a lower risk of liver cancer mortality than male patients in utmost age groups. Conclusion: Age is positively correlated with liver diseases-related mortality risk in patients with hepatitis B-related liver cirrhosis. Female sex is a protective factor for liver cancer mortality in patients with liver cirrhosis, and the protective effect on liver cirrhosis complications mortality risk gradually disappears with age.

[Comparative analysis of comprehensive health status among 31 provinces in China and 134 countries (regions) in 2015]

Objective: To evaluate comprehensive health status of 31 provinces in China and compare with other countries (regions). Methods: Social-demographic index, life expectancy and healthy life expectancy in 134 countries (regions) and 31 provinces in China were collected from the Global Burden of Disease Study 2015. K-means clustering method was used to classify comprehensive health status of various countries (regions) in the world. HemI 1.0.3 software was applied to draw distribution heat maps of social-demographic index, life expectancy and healthy life expectancy in different provinces of Mainland China. Discriminant analysis was used to evaluate comprehensive health status of different provinces in Mainland China. Results: Comprehensive health status of 134 countries (regions) was grouped into category 1-8 from good to poor, and Mainland China was in the category 4. The comprehensive health status of provinces in Mainland China is better in the east coast and poorer in the west inland, among which Shanghai and Beijing were grouped into the category 1, Zhejiang, Jiangsu, Guangdong and Tianjin into the category 2, Fujian, Liaoning and Shandong into the category 3, Yunnan, Guangxi, Xinjiang and Guizhou into the category 5, Qinghai and Tibet into the category 6, and the rest 16 provinces into the category 4. Conclusion: Comprehensive health status of Mainland China ranked middle to upper level in the world, and health status disparities were observed among different provinces in Mainland China.

Analysis of Causes of Death and Related Factors of 102 Perinatal Infants in Chongqing

OBJECTIVES

To analyze the causes of perinatal death and related factors from the perspective of forensic medicine, and to provide references for reducing perinatal mortality and guidance for forensic identification.

METHODS

A retrospective analysis was performed on 102 cases of perinatal autopsy with clinical data from the Department of Forensic Medicine of Chongqing Medical University in 2004-2016.

RESULTS

Of the 102 cases of perinatal deaths, 66 （64.71%） were neonatal deaths, 24 （23.53%） were stillborn foetuses, and 12 （11.76%） were stillbirths. Among the 66 neonatal death cases, 39 （59.09%） died within 1 d, 19 （28.79%） died within 1-3 d, and 8 （12.12%） died within >3-7 d of birth. The top 3 causes of neonatal death were pulmonary diseases, congenital malformation, umbilical cord and placental abnormalities. The causes of stillborn foetus and stillbirth were mainly umbilical cord and placental abnormalities, and intrauterine asphyxia.

CONCLUSIONS

Pulmonary diseases, umbilical cord and placental abnormalities, and congenital malformations are the main causes of perinatal death. In order to reduce the perinatal mortality, pre-pregnancy examination and prenatal care should be strengthened, and the knowledge of pregnancy care should be popularized.

Effect of N-acetyl-l-methionine supplementation on lactation performance and plasma variables in mid-lactating dairy cows

The objective of current study was to investigate the effect of N-acetyl-l-methionine (NALM) supplementation on lactation performance and plasma variables in mid-lactating dairy cows. Forty-eight multiparous cows were blocked into 12 groups based on parity, days in milk, and milk production and were randomly assigned to 1 of the 4 treatments: 0, 15, 30, or 60 g/d of NALM per cow to supplement the basal diet. The experiment was conducted over a 13-wk period, with the first week as adaptation. The yields of milk, fat-corrected milk, and milk lactose were increased quadratically, and energy-corrected milk yield tended to increase with increased NALM supplementation in a quadratic manner. The dry matter intake, milk protein yield, milk fat yield, contents of milk composition (protein, fat, lactose, total solids, and milk urea nitrogen), feed efficiency, and body weight change were not affected by NALM supplementation. In addition, plasma methionine concentration was increased quadratically, and proline, total nonessential AA, and total AA concentrations were significantly higher in the 30 g/d group compared with that of the control group. However, other AA and total essential AA concentrations were not affected with supplementation of NALM. Adding NALM increased concentrations of total protein and globulin in plasma, but decreased plasma urea nitrogen concentration in a quadratic manner. Meanwhile, plasma malonaldehyde concentration decreased linearly as doses of NALM addition increased. Our results suggested that the supplementation of NALM improved milk yield and protein synthesis in the liver, and lowered lipid peroxidation in mid-lactating dairy cows.

[Probability of premature mortality caused by non-communicable diseases in Beijing, 2010-2015]

Objective: To understand the probability of premature mortality caused by non-communicable diseases (NCD) in Beijing from 2010 to 2015. Methods: The data of deaths from Beijing vital registration system were used to analyze age-standardized NCD mortality rates, proportion of NCD deaths in age group <70 years and premature NCD mortality. Results: NCD deaths accounted for 90% of the total deaths in Beijing. Age-standardized NCD death rate decreased from 332.43/100 000 in 2010 to 280.02/100 000 in 2015. Meanwhile, the probability of deaths from four NCDs between in age group 30-70 years (premature NCD mortality) decreased from 12.81% to 11.11% in Beijing. The premature mortality of four NCDs in men was 14.63%, and compared with 2015 baseline, it would decrease by 16.4% to reach 2025 goal (12.23%), and the probability of premature mortality four NCDs in women was 7.54%, and compared with 2015 baseline, it would decrease by 6.8% to reach the 2025 goal (7.03%). People living in suburb areas had a higher probability of premature NCD mortality (13.67%) than those living in urban areas (9.72%) in Beijing in 2015. Conclusions: The premature NCD mortality was much higher in men than in women in Beijing. More attention should be paid to the control of risk factors for NCD premature deaths, especially in men and in suburb residents, to reach the 25×25 goal.

[Analysis on causes of death of residents in Beijing, 1965-1974]

OBJECTIVE

To fill up the absence of data on causes of death of urban residents in Beijing during 1965-1974 and provide evidence for the similar study in other areas.

METHODS

All possible sources for death data during 1965-1974 were identified through expert consultations and record search. Stratified sampling was conducted to collect the death data of urban residents during this period in Beijing. The mortality rate, death cause constituent and rank of death causes were used in this descriptive analysis.

RESULTS

A total of 11 668 records of deaths from 1965 to 1974 were collected from 10 local police stations in urban area of Beijing. The top 10 death causes in the urban residents were heart disease, tumor, cerebrovascular disease, accidental injury, respiratory system disease, digestive system disease, communicable disease and parasitic disease, nervous system disease, urogenital and reproductive system disease, endocrine and nutrition metabolic diseases. The deaths caused by these diseases accounted for 84.19% of the total deaths. Accidental injury accounted for 13.22% of the total deaths, which was significantly higher than that in either 1964 or 1975, two years before and after this period(P<0.01). Suicide accounted for 54.47% of the total accidental injury deaths. For men, accidental injury was the leading death cause, followed by cancer and heart disease; for women, heart disease, cancer and cerebrovascular disease were the top three death causes.

CONCLUSION

The major death cause in urban residents changed from infectious diseases to chronic and non-communicable diseases during 1965-1974. A remarkable high proportion of deaths caused by accidental injury was due to the historical background during that period in Beijing, China.

[Influencing factors on healthy life expectancy in adults in Beijing]

OBJECTIVE

To understand the main influencing factors related to healthy life expectancy (HALE) among adults in Beijing.

METHODS

The calculation on health-adjusted life expectancy was performed by Sullivan METHODS. Data from the self-reported health survey program on adults in Beijing 2012 was gathered. Hierarchical ordered probit model was used to estimate the severity-weighted prevalence of disability and then combined with the period life table to obtain the HALE. Factors associated with the severity-adjusted prevalence of the disabled were analyzed under the generalized additive models (GAM).

RESULTS

The main influencing factors of HALE would include age (t=40.351, P<0.001), sex (t=9.689, P<0.001), levels of education (t=5.021, P< 0.001), exercise (t=5.487, P<0.001) and alcohol intake (t=-2.380, P=0.017) etc. The influence of per capita monthly income (χ(2) =3.949, P=0.044) showed as non-linear.

CONCLUSIONS

Levels of income would directly influence the severity-weighted prevalence of the disability, which also affecting the HALE. Programs on improving healthy life style and health care in women should be promoted.

The Effects of Dietary Phosphorus on the Growth Performance and Phosphorus Excretion of Dairy Heifers

The objective of this study was to investigate the effects of reducing dietary phosphorus (P) on the frame size, udder traits, blood parameters and nutrient digestibility coefficient in 8- to 10-month-old Holstein heifers. Forty-five heifers were divided into 15 blocks according to the mo of age and were randomly assigned one of three dietary treatments: 0.26% (low P [LP]), 0.36% (medium P [MP]), or 0.42% (high P [HP]) (dry matter basis). Samples were collected at the wk 1, 4, 8. The results show that low dietary P had no effect on body measurement. The blood P concentration decreased with decreasing dietary P (p<0.05), while the blood calcium content of LP was higher than that of the MP and HP groups (p<0.05), though still in the normal range. The serum contents of alkalinephosphatase, potassium, and magnesium were similar among the treatments. No differences were found in all nutrients' apparent digestibility coefficients with varied dietary P. However, with P diet decreased from HP to LP, the total fecal P and urine P concentration declined significantly, as did fecal water soluble P (p<0.05). In conclusion, reducing the dietary P from 0.42% to 0.26% did not negatively affect the heifers' growth performance but did significantly lessen manure P excretion into the environment.

The formation and degradation of active species during methanol conversion over protonated zeotype catalysts

The methanol to hydrocarbon (MTH) process provides an efficient route for the conversion of carbon-based feedstocks into olefins, aromatics and gasoline. Still, there is room for improvements in product selectivity and catalytic stability. This task calls for a fundamental understanding of the formation, catalytic mechanism and degradation of active sites. The autocatalytic feature of the MTH process implies that hydrocarbons are active species on the one hand and deactivating species on the other hand. The steady-state performance of such species has been thoroughly studied and reviewed. However, the mechanism of formation of the initial hydrocarbon species (i.e.; the first C-C bond) and the evolution of active species into deactivating coke species have received less attention. Therefore, this review focuses on the significant progress recently achieved in these two stages by a combination of theoretical calculations, model studies, operando spectroscopy and catalytic tests.

Polymorphisms in the coding region of X-ray repair complementing group 4 and aflatoxin B1-related hepatocellular carcinoma

X-ray repair complementing group 4 (XRCC4) is very important in maintaining overall genome stability and may play an important role in carcinogenesis. We aimed to investigate the role of polymorphisms in the coding region of this gene in hepatocellular carcinoma (HCC) caused by aflatoxin B1 (AFB1). A hospital-based case-control study, including 1,499 HCC cases and 2,045 controls without any liver diseases or tumors, was conducted in a high AFB1 exposure area (the Guangxi region) to assess the relationship between 21 polymorphisms in the coding region of XRCC4 and AFB1-related HCC risk and prognosis. Among these 21 polymorphisms, only rs28383151 modified HCC risk. These individuals with the genotypes of rs28383151 A alleles (rs28383151-GA/AA), compared with the homozygote of rs28383151 G alleles (rs28383151-GG), faced increasing risk of HCC (odds ratio [OR]: 2.17; 95% confidence interval: 1.77-2.67). Significant interactive effects between risk genotypes (OR, >1) and AFB1 exposure status were also observed in the joint-effects analysis. Furthermore, this polymorphism was correlated not only with lower XRCC4-expressing levels, but also with higher AFB1-DNA adducts levels and increasing TP53M and portal vein tumor risk. The rs28383151 polymorphism modified the recurrence-free survival and overall survival of HCC patients, especially under high AFB1 exposure conditions. Additionally, this polymorphism multiplicatively interacted with the glutathione S-transferase M1 polymorphism with respect to HCC risk (ORinteraction = 2.13).

CONCLUSION

Genetic polymorphisms in the coding region of XRCC4 may be risk and prognostic biomarkers of AFB1-related HCC, and rs28383151 is such a potential candidate.

Genetic variation of chicken MC1R gene in different plumage colour populations

1. Genetic variation in the chicken MC1R gene was analysed through bioinformatic methods after polymerase chain reaction (PCR) amplification and sequencing of the coding region of MC1R gene from 5 different populations with 4 plumage colours (black, grey plumage with black spots, yellow plumage with black spots, red). 2. A total of 11 novel variations were detected in Hebei chickens, of which 8 were non-synonymous. Allele distribution analysis showed that the wild-type e(+) (Brown Leghorn) allele was mainly found in Hy-Line Brown and Lohmann Brown, the dominant Extended black E(AY220304) allele was mainly found in Hebei chicken with black plumage, whereas the Buttercup (e(bc)) allele was rare. 3. Nucleotide diversity (π) within each colour strain of Hebei chickens (0·0047-0·0052) was significantly greater than that of Hy-Line Brown (0·0024) or Lohmann Brown (0·0043). 4. The results indicate that there is abundant polymorphism in the MC1R gene, especially in Hebei chicken, which was associated with its rich plumage colour diversity.

Genetic variation of major histocompatibility complex BLB2 gene exon 2 in Hebei domestic chicken

Genetic variation of MHC BLB2 gene exon 2 in Hebei domestic chicken was investigated, after PCR and sequencing of a 374bp fragment (containing entire exon 2 (270bp) of BLB2 gene) in 76 individuals. The results showed that along this fragment, there were 69 variable sites, of which 18 were novel variations, and 82 estimated haplotypes with the diversity of 0.960. In Hebei domestic chicken, the nucleotide diversity (π), the average number of nucleotide differences (k), the average number of nucleotide diversity of synonymous substitution (π(s)) and non-synonymous substitution (π(a)) in BLB2 gene exon 2 were 0.098, 24.688, 0.075, and 0.106, respectively; nine non-synonymous substitutions was exclusively found in the peptide-binding sites (PBS) region of BLB2 gene exon 2, inferring that these unique substitutions might be helpful to resist some special bacteria and pathogens. The higher genetic diversity of MHC BLB2 gene exon 2 in Hebei domestic chicken might be consistent with its more robust disease resistance.

Blood gas, hemoglobin, and growth of Tibetan chicken embryos incubated at high altitude

Metabolism and hatchability are impaired when chicken eggs laid at sea level are incubated at high altitude. The Tibetan chicken is an excellent local poultry breed that inhabits altitudes of 2,900 m and has a hatchability of approximately 75% at that altitude. To understand how Tibetan chicken embryos develop successfully at high altitude, we compared blood gas, pH, hemoglobin concentrations and embryo mass for Tibetan chicken embryos (T) and for embryos from a dwarf breed (D) that normally is reared at sea level. The 2 breeds (T and D) and 2 incubation altitudes (2,900 m = high, H; and 100 m = low, L) were compared at 9, 12, 15, and 18 d of incubation. Embryo weights were lower for the high altitude groups (TH, DH) than for the low altitude groups at all stages of incubation. The embryo mass of TH appeared to increase more quickly than that of DH. Compared with DH, TH embryos had lower arterialized oxygen partial pressure on d 18, higher venous carbon dioxide partial pressure from d 12 to 18, and higher hemoglobin concentration and lower venous blood pH values on d 12 and 15. These findings indicate that the ability of the Tibetan chicken embryos to adapt to the high altitude may be due to the increase in hemoglobin concentration, which augments the blood oxygen-carrying capacity. In addition, the higher venous carbon dioxide partial pressure and lower venous blood pH promote unloading of oxygen from hemoglobin.

[Significance of electron microscopy in differential diagnosis of small cell neoplasms]

The diagnosis of small cell anaplastic neoplasms is one of the difficult problems in routine pathology. In some cases, it is almost impossible by light microscopy (LM) to arrive at a correct diagnosis. Electron microscopy (EM) may contribute greatly in solving this problem. However, it is impractical to make EM examination as a routine in every difficult neoplasm. Therefore, we have reviewed, by EM specimens of 21 cases (9 cases of small cell carcinoma and 12 cases of lymphoma, previously diagnosed by LM in this hospital), and compared the light and ultrastructural features of these tumors. We found that the most important light microscopic feature to differentiate lymphoma from small cell carcinoma is the nuclear structure of tumor cells. According to the characteristics such as the shape of nuclei, the distribution of chromatin, the stereoscopic impression of nuclear section plane while focusing, the appearance of nucleoli, it is often possible to arrive at a correct diagnosis of lymphoma or small cell carcinoma by LM.