[High-risk sexual behaviors of HIV/AIDS and related factors in young students in Guangzhou]

Objective: To explore high-risk sexual behaviors of HIV/AIDS and related factors in young students in Guangzhou. Methods: A cross-sectional survey was conducted in 5 different types of Guangzhou colleges by convenience sampling with minimum number of classes per grade and 600 samples per school from September to November 2021. The R 4.2.2 software was used to consolidate databases. Simultaneously, a logistic regression model and a decision tree algorithm model, stratifying by whether sexual behaviors had occurred before, were constructed. In each layer, the prediction performance of the two models was evaluated through area under receiver operating characteristic and the confusion matrix, and then the model with high prediction performance was retained. Results: A total of 7 346 students were surveyed. The proportion of the respondents reporting sexual experience were 9.08% (667/7 346), in whom 26.24% (175/667) had risky sexual activity in the past year. The decision tree algorithm model performs well in predicting whether high-risk sexual behaviors have occurred in the past year. When the complexity parameter value is 0.018, and nsplit reaches 4, which means there are 5 leaf nodes in the model, the cross error of the tree will be the smallest. The first best grouping variable in the decision tree was whether to use condoms throughout the first sexual behavior. If condoms were used at their sexual debut, but homosexual practices have occurred in the past year, the probability of risky sexual behavior will increase. If homosexual practices have not occurred in the past year, but the age of sexual debut was below 18 years old while the period of HIV education was after high school, the probability of risk sexual behavior will also increase. Conclusions: AIDS-related risky behaviors of young students still deserved attention. The experience of sexual debut and whether AIDS-related health education has been received before the sexual debut were significant predictors for the occurrence of high-risk sexual behavior. The decision tree algorithm model has particular applicability for predicting and screening potential risk populations.

[Perception of HIV-related behavior and influencing factors among young students in Guangzhou]

Objective: To investigate the risk perception for risky behavior of HIV/AIDS infection among young students and to analyze the related influencing factors. Methods: A cross-sectional survey was conducted in 5 different types of Guangzhou colleges from September to November 2021, in which convenience sampling and a minimum number of classes per grade and 600 samples per school were used according to the national unity program. Disordered multi-classification logistic regression was used to construct a risk perception model and analyze influencing factors in different risk perception levels. Results: A total of 7 346 young students were surveyed, and most rated themselves at low risk of HIV/AIDS infections (90.58%, 6 654/7 346). A total of 89.10% (6 545/7 346) of subjects' perception of their HIV/AIDS infection risk was consistent with their risk behavior, while 10.90% (801/7 346) was inconsistent. Among those inconsistent subjects, 19.10% (153/801) showed underestimating their risk , while 80.90% (648/801) seen overestimating their risk. Disordered multi-classification logistic regression analysis showed that, after controlling for other factors, compared with the non-sexual group, respondents whose first sex age under 18 had a higher rate of underestimating their risk of infection (OR=129.39, 95%CI: 73.28-228.48), as well as a higher rate of overestimated their risk of infection (OR=1.76, 95%CI: 1.04-2.99). First sexual intercourse at age 18 or older was a risk factor for underestimating risk (OR=70.56, 95%CI: 42.72-116.53), but was not statistically associated with overestimating risk. Being female, other school type, non-heterosexual orientation, and self-rated HIV-related knowledge as fair or no knowledge were risk factors for overestimating risk but were not statistically associated with underestimating risk. Conclusions: Overall, young students in universities of Guangzhou have a good risk perception of HIV/AIDS infection. Individual factors, education factors and sexual experience will influence students' risk perception of HIV/AIDS infection. Raising the awareness rate of HIV/AIDS knowledge and delaying the age of first sexual intercourse will improve the risk perception ability of young students.

[Clinical and genetics characteristics of adult-onset cerebrotendinous xanthomatosis: analysis of a Chinese pedigree]

Objective: Clinical manifestations, imaging findings, pathologic features, and genetic mutations of Chinese adult patients with cerebrotendinous xanthomatosis (CTX) were analyzed in order to achieve a greater understanding of CTX that can improve early detection, diagnosis, and treatment. Methods: Clinical data including medical history, neurologic and auxiliary examinations, imaging findings, and genetic profile were collected for an adult patient with CTX admitted to the Sixth Medical Center of Chinese People's Liberation Army General Hospital in August 2020. Additionally, a systematic review of genetically diagnosed Chinese adult CTX cases reported in major databases in China and other countries was performed and age of onset, first symptoms, common signs and symptoms, pathologic findings, imaging changes, and gene mutations were analyzed. Results: The proband was a 39-year-old female with extensive, early-onset nervous system manifestations including cognitive dysfunction and ataxia. Systemic lesions included juvenile cataract and a tendon mass. Cranial magnetic resonance imaging revealed cerebral atrophy, symmetric white matter changes predominantly in the pyramidal tract, and lesions in the cerebellar dentate nucleus. A novel homozygous mutation in the sterol-27-hydroxylase (CYP27A1) gene (c.1477-2A>C) was identified. There were no family members with similar clinical presentation although some were carriers of the c.1477-2A>C mutation. The patient showed a good response to deoxycholic acid treatment. Totally there were 56 cases of adult CTX patients in China, mostly in East China (31/56, 55.4%), at a male-to-female ratio of 1.8 to 1. Multiple organs and tissues including nervous system, tendon, lens, lung, and skeletal muscle were affected in these cases. The most common neurologic manifestations were cognitive dysfunction (44/52, 84.6%) and ataxia (44/51, 86.3%). The cases were characterized by early onset, chronic progressive damage of multiple systems, long disease course, and delayed diagnosis, making the disease difficult to manage clinically and resulting in poor prognosis. The 2 most common genetic mutations in Chinese adult CTX patients were c.1263+1G>A and c.379C>T. Exon 2 of the CYP27A1 gene was identified as a mutation hot spot. Conclusions: Chinese adult patients with CTX have complex clinical characteristics, a long diagnostic cycle, and various CYP27A1 gene mutations. Early diagnosis and intervention can improve the prognosis of these patients.

[Differential diagnosis model of benign and malignant breast BI-RADS category 4 nodules based on serum SP70 and conventional laboratory indicators]

Objective: To develop a nomogram model for the differential diagnosis of benign and malignant breast BI-RADS (Breast Imaging Reporting and Data System) category 4 nodules based on serum tumor specific protein 70 (SP70) and conventional laboratory indicators and validate its predictive efficacy. Methods: A case-control study design was used to retrospectively analyze the data of 429 female patients diagnosed with BI-RADS category 4 breast nodules by breast color doppler flow imaging at the First Affiliated Hospital of Nanjing Medical University from January 2021 to April 2022 with an age range of 16 to 91 years and a median age of 50 years, and the patients were divided into a training cohort (314 patients) and a validation cohort (115 patients) according to the inclusion time successively. Using postoperative pathological findings as the"gold standard", univariate and multivariate logistic regression analyses were used to identify the predictor variables used for the model. The nomogram, receiver operating characteristic (ROC) curves and calibration curves were drawn for the prediction model, and the discrimination and calibration of the model were evaluated using the consistency index (C-index) and calibration plots. Results: The postoperative pathological results showed that 286 (66.7%) were malignant nodules and 143 (33.3%) were benign nodules of 429 breast BI-RADS category 4 nodules. The serum SP70 (OR=1.227,95%CI: 1.033-1.458,P=0.020), NLR (OR=1.545,95%CI: 1.047-2.280,P=0.028), LDL-C (OR=2.215, 95%CI: 1.354-3.622, P=0.002), GLU (OR=2.050,95%CI:1.222-3.438,P=0.007), PT (OR=1.383,95%CI: 1.046-1.828,P=0.023), nodule diameter (OR=1.042, 95%CI: 1.008-1.076, P=0.015) and age (OR=1.062,95%CI: 1.011-1.116,P=0.016) were independent risk factors which could be used to distinguish benign and malignant breast BI-RADS category 4 nodules (P<0.05). The nomogram was plotted by the above seven independent variables, and the concordance index (C-index) for the training cohort and validation cohort were 0.842 (95%CI:0.786-0.898) and 0.787 (95%CI:0.687-0.886), respectively. The sensitivity and specificity of using this model to identify benign and malignant breast BI-RADS category 4 nodules in the training and validation cohort were 83.5%, 72.5% and 79.2%, 73.6%, respectively. The calibration curves showed good agreement between the predicted and actual values in the nomogram. Conclusions: This study combined serum SP70, conventional laboratory indicators and breast color doppler flow imaging to develop a nomogram model for the differential diagnosis of benign and malignant breast BI-RADS category 4 nodules. The model may have good predictive efficacy and may provide a basis for clinical treatment options, which is beneficial for guiding breast cancer screening and prevention.

[Analysis and forecast of burden of pancreatic cancer along with attributable risk factors in Asia countries between 1990 and 2019]

Objective: To analyze the disease burden of pancreatic cancer in major Asian countries and forecast the burden of that in China, which helps to provide reference for the prevention and control of pancreatic cancer. Methods: Data on disease burden of pancreatic cancer among global and major Asian countries from on the Global Burden of Disease (GBD) 2019 were collected to describe burden distribution through the absolute numbers or standardized rates of incidence, death and disability adjusted life years (DALY) by year, sex and socio-demographic index. Estimated annual percentage changes (EAPC) was used to assess the trend of standardized rate. The proportion of deaths attributable to risk factors for pancreatic cancer in 2019 was used to compare by age, sex and region. ARIMA model was performed with R language to predict change of age-standardized incidence and death rates of pancreatic cancer from 2020 to 2029. Results: From 1990 to 2019, the standardized incidence rates of pancreatic cancer in China increased from 3.17/100 000 to 5.78/100 000, and the standardized death rate increased from 3.34/100 000 to 5.99/100 000. The increases exceeded other high-income Asia countries. In the past three decades, the standardized incidence, death and DALY rates of pancreatic cancer in global have increased year by year. Among the major countries in Asia, China has the highest growth rate of disease burden (EAPC of standardized incidence rates=2.32%, 95% CI: 2.10%-2.48% and EAPC of standardized death rate=2.25%, 95% CI: 2.03%-2.42%). In addition, incidence and death rates of pancreatic cancer in China are expected to continue on the rise between 2000 and 2029 by ARIMA model. Incidence rate is expected to increase 15.92% and death rate is expected to increase 15.86%. Conclusions: The standardized incidence and death rates of pancreatic cancer in China increase year by year with an increasing trend for the burden of disease. The disease burden of pancreatic cancer is expected to rise due to the increase and aging of the population. Preventive measures should be adopted to decrease the burden of the pancreatic cancer.

[Clinical value of tumor-associated autoantibodies in diagnosis of early non-small cell lung cancer]

Objective: To investigate the auxiliary diagnostic value of seven tumor-associated autoantibodies (AABs) P53, PGP9.5, SOX2, GAGE7, GBU4-5, MAGEA1 and CAGE in early non-small cell lung cancer (NSCLC). Methods: The case-control study enrolled 195 patients with early NSCLC [71 males and 124 females, aged (55.70±11.78) years old], 114 patients with benign lung disease [44 males and 70 females, aged (52.85±12.31) years old] and 100 healthy subjects [39 males and 61 females, aged (53.62±9.97) years old] from the First Affiliate Hospital of Nanjing Medical University from June 2020 to December 2020. AABs were detected by enzyme-linked-immunosorbent serologic assay (ELISA), and carcinoembryonic antigen (CEA),cytokeratin 19-fragments (CYFRA21-1) and neuron specific enolase (NSE) were detected by electrochemiluminescence. The levels of AABs,CEA,CYFRA21-1 and NSE in the 3 groups were compared. Patients with benign lung diseases and healthy subjects were combined into the control group, and the positive rate of each indicator in the NSCLC group and the control group was compared. The diagnostic efficacy of single and combined tests for NSCLC were obtained using receiver operating characteristic (ROC) curves. Besides, the relationship between the levels of AABs, CEA, CYFRA21-1 and NSE and their clinicopathological features and preoperative imaging parameters in NSCLC patients was assessed. Results: The levels of SOX2 [0.70 (0.10, 2.40) U/mL] and GBU4-5 [1.30 (0.30, 8.90) U/mL] in NSCLC group were higher than those in benign disease group [SOX2: 0.50 (0.10, 1.60) U/mL, GBU4-5: 0.80 (0.10, 2.30) U/mL, Z values were 27.258 and 45.797; P values were all<0.05] and health control group [SOX2: 0.45 (0.10, 1.08) U/mL, GBU4-5: 0.75 (0.20, 1.78) U/mL, Z values were 32.551 and 40.456; P values were all<0.05], and there was no significant difference between benign disease group and health control group (Z values were 5.293 and 5.340, P values were all>0.05). The levels of CEA [1.75 (1.08, 2.72) U/mL] and CYFRA21-1 [1.81 (1.41, 2.36) U/mL] in NSCLC group were higher than those in healthy control group [CEA: 1.22 (0.68, 1.81) U/mL, CYFRA21-1: 1.43 (1.14, 1.74) U/mL, Z values were 64.100 and 37.597; P values were all<0.05], but there was no significant difference between NSCLC group and benign group [CEA: 1.74 (1.01, 2.51) U/mL, CYFRA21-1: 1.82 (1.45, 2.46) U/mL, Z values were 7.275 and 10.621; P values were all>0.05]. The positive rates of P53, SOX2, GAGE7, GBU4-5 and CEA in NSCLC group were higher than those in the control group [P53: 10.3% vs 0.9%, SOX2: 11.3% vs 2.3%, GAGE7: 11.3% vs 0.5%, GBU4-5: 30.1% vs 5.6%, CEA: 9.7% vs 0.9%, χ² values were 17.420, 13.242, 22.485, 43.211, 16.255, respectively; P values were all<0.05]. The diagnostic efficiency of the combined detection of seven AABs was better than that of single detection. Seven AABs combined with CEA [area under curve (AUC): 0.732, sensitivity: 64.10%] and with CYFRA21-1 (AUC: 0.737, sensitivity: 58.97%) greatly improved the diagnostic efficiency and sensitivity of CEA (AUC: 0.583, sensitivity: 50.77%) and CYFRA21-1 (AUC: 0.552, sensitivity: 44.10%). The levels of SOX2 and CEA in NSCLC patients were correlated with the degree of tumor invasion (H values were 6.436 and 14.071; P values were all<0.05); the levels of GAGE7 and CEA were correlated with the nodule density (H values were 7.643 and 12.268; P values were all<0.05); and the levels of SOX2, GAGE7, CEA and CYFRA21-1 were all correlated with the nodule size (H values were 10.837, 11.528, 31.835, 20.338; P values were all<0.05). Conclusion: The detection of AABs combined with CEA and CYFRA21-1 is helpful for the early auxiliary diagnosis of NSCLC, and plays an important role in prevention and screening for early lung cancer.

[Risk factors and risk model of lymph node metastasis in early gastric cancer]

To investigate the risk factors of lymph node metastasis in early gastric cancer (EGC) and to develop a risk model for the presence of lymph node metastasis. A total of 172 EGC patients, with a median age of 62(52, 68) years, who underwent gastric cancer resection in the First Affiliated Hospital of Nanjing Medical University from January 2017 to June 2019 were selected. Clinical data of the patients were collected through the case system. Logistic regression analysis was used to determine the variables significantly related to lymph node metastasis. ROC curve and calibration curve were used to evaluate the risk model. The results showed that the lymph node metastasis rate of 172 EGC patients was 19.19% (33/172). Tumor size, depth of invasion, degree of differentiation and vascular tumor thrombus were associated with lymph node metastasis (P<0.05), but age ≥ 60 years (OR=5.556, 95%CI: 1.757-17.569, P=0.004), invasion depth (OR=4.218,95%CI:1.418-12.548, P=0.010) and vascular cancer embolus (OR=13.878,95%CI:4.081-47.196,P<0.001) were independent risk factors for lymph node metastasis of EGC. The consistency index of the risk model based on the above risk factors was 0.8835 (95%CI: 0.818 8-0.948 2). The calibration curve shows that the risk assessment model is in good agreement with the actual results, indicating that the model has high accuracy and discrimination.The most common site of metastasis was group 3, followed by group 4. Therefore, patients over 60 years old with submucosal invasion and vascular tumor thrombus may have a higher risk of lymph node metastasis.

Acute flaccid paralysis and neurogenic respiratory failure associated with enterovirus D68 infection in children: Report of two cases

BACKGROUND

Acute flaccid paralysis (AFP) and neurogenic respiratory failure rarely occur in children. At the end of 2018, some children with such symptoms were admitted to our hospital. In this study, we aimed to assess two children with AFP and neurogenic respiratory failure associated with enterovirus D68 (EV-D68).

CASE SUMMARY

Two children admitted to our hospital presented with symptoms and imaging results different from those of acute disseminated encephalomyelitis and hand, foot, and mouth disease. Their main symptoms were AFP and neurogenic respiratory failure. Magnetic resonance imaging showed severe inflammatory injury mainly to the anterior horn cells of the spinal cord. Blood and cerebrospinal fluid samples were collected to assess for pathogens, including bacteria, tuberculosis, cryptococcus, herpes virus, and coxsackie virus, and the results were negative. At the beginning, the two cases were not assessed for EV-D68 in the nasopharyngeal, blood, and cerebrospinal fluid specimens. About 2 mo later, EV-D68 was detected in the stool sample of one of the cases. The symptom of AFP was caused by injury to the anterior horn cells at levels C5-L5 of the spinal cord, while neurogenic respiratory failure was at levels C3-C5.

CONCLUSION

We should pay attention to the detection and diagnosis of EV-D68 and make efforts to develop antivirus drugs and vaccines.

[The value of NLR, FIB, CEA and CA19-9 in colorectal cancer]

Objective: To investigate the clinical value of neutrophil-lymphocyte ratio (NLR), fibrinogen (FIB), carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) in the diagnosis and prognosis of colorectal cancer. Methods: A case-control study design was used to select 155 patients with colorectal cancer[98 males and 57 females, aged (63.12±13.99)years old], 90 patients with colorectal polyps[62 males and 28 females, aged (56.86±12.74)years old] and 150 healthy subjects[93 males and 57 females, aged (57.02±10.91)years old] from the First Affiliated Hospital of Nanjing Medical University from October 2017 to March 2018. Blood routine tests were detected by instrument method, FIB was detected by Clauss method, and CEA and CA19-9 were detected by electrochemiluminescence method. The levels of the NLR, FIB, CEA and CA19-9 in the 3 groups were compared. The diagnostic efficacy of NLR, FIB, CEA and CA19-9 of colorectal cancer was compared according to the ROC curve. The relationship between the level of NLR, FIB, CEA and CA19-9 and their clinicopathological features in colorectal cancer patients was assessed. According to the median levels of NLR, FIB, CEA and CA19-9, 112 follow-up of colorectal cancer patients could be divided into the high-value group and the low-value group. Kaplan-Meier, log-rank test and Cox regression analysis were used to analyze the relationship between the levels of the four indicators and the prognosis of colorectal cancer. Results: The levels of NLR, FIB, CEA and CA19-9 in colorectal cancer group were 2.11(1.52, 2.86), 3.21(2.58, 3.86)g/L, 3.93(2.27, 8.78)μg/L, 15.11(9.10, 25.73)U/ml. The levels of NLR, FIB, CEA and CA19-9 in colorectal polyp group were 1.74(1.39, 2.17), 2.54(2.26, 3.03)g/L, 1.99(1.18, 2.70)μg/L, 9.83(6.13, 15.68)U/ml. The levels of NLR, FIB, CEA and CA19-9 in healthy control group were 1.68(1.33, 2.28), 2.56(2.30, 2.82)g/L, 1.85(1.28, 2.59)μg/L, 10.03(6.86, 13.26)U/ml. The levels of NLR, FIB, CEA and CA19-9 in colorectal cancer group were significantly higher than those in colorectal polyp group (Z values were 3.568, 5.913, 6.880 and 4.022,P values were all<0.05) and healthy control group(Z values were 3.916, 7.381, 9.131 and 5.251,P values were all<0.05). The levels of NLR, FIB, CEA and CA19-9 in colorectal polyp group were not remarkably different from those in healthy control group (Z values were 0.217, 0.179, 0.320 and 0.061,P values were all>0.05). The diagnostic performance of CEA was the best in single test, followed by FIB, CA19-9 and NLR. The sensitivity of combined NLR+FIB+CEA or NLR+FIB+CEA+CA19-9 was the highest with 72.3%. NLR and FIB levels were associated with tumor sites (Z values were 3.587 and 7.089,P values were both<0.05). FIB and CEA levels were correlated with the depth of tumor invasion (Z values were 3.250 and 3.245, P values were both <0.05). NLR, FIB, CEA and CA19-9 levels were both associated with lymph node metastasis (Z values were 2.010, 3.276, 3.312 and 2.921, P values were all<0.05). The prognosis of patients in the high-value NLR, FIB, CEA and CA19-9 groups was significantly worse than that in the low-value group (χ² values were 5.744, 6.048, 4.389 and 6.942,P values were all<0.05).Cox multivariate regression analysis showed lymph node metastasis, NLR >2.15 and CA19-9 >15.47 U/ml are independent factors affecting the prognosis of colorectal cancer. Conclusion: NLR, FIB, CEA and CA19-9 can be applied in the auxiliary diagnosis and prognosis of colorectal cancer.

Hydrogen inhalation inhibits microglia activation and neuroinflammation in a rat model of traumatic brain injury

Traumatic brain injury (TBI) is a major cause of mortality and disability worldwide. To date, therapies to treat any forms of TBI are still limited. Recent studies have demonstrated the potential neuroprotective effects of molecular hydrogen on TBI. Although it has been demonstrated that hydrogen inhalation (HI) for about 5 hrs immediately after TBI has a beneficial effect on brain injury, the most effective intervention procedure in the treatment of TBI remains unknown. The mechanism underlying the neuroprotective effects of HI on TBI also needs to be further investigated. Our results showed that inhalation of 4% hydrogen during the first day after TBI was the most effective hydrogen intervention procedure in the treatment of TBI. Pathological examination showed that HI could attenuate TBI-induced reactive astrocytosis and microglial activation. Nissl staining demonstrated a significant decrease in the number of nissl-stained dark neurons (N-DNs) in HI group compared to TBI group at 2 h post-TBI, and the TBI-induced neuronal loss was attenuated by HI at day 3 post-TBI. IHC staining showed that HI resulted a decrease in CD16-positive cells and a further increase in CD206-positive cells as compared to TBI group. Multiplex cytokine assay demonstrated the most profound regulatory effects induced by HI on the levels of IL-12, IFN-γ, and GM-CSF at 24 h post-TBI, which confirmed the inhibitory effect of hydrogen on microglia activation. We concluded that inhalation of 4% hydrogen during the first day after TBI was the most effective intervention procedure in the treatment of TBI. Our results also showed that hydrogen may exert its protective effects on TBI via inhibition of microglia activation and neuroinflammation.

Age Estimation and Age-related Facial Reconstruction of Xinjiang Uygur Males by Three-dimensional Human Facial Images

OBJECTIVES

To search age-correlated facial features and construct an age estimation model based on the three-dimensional （3D） facial images of Xinjiang Uygur males, and to structure individual face images of old age and young age.

METHODS

Pretreatment was performed to collect 105 3D facial images of Xingjiang Uygur males aged between 17-57 years by Artec Studio software. The facial images were transferred to high-density 3D dot matrix data by FaceAnalysis software, and each image could be represented with 32 251 vertexes. Central correction of the facial images was done and all the data were aligned to a standard coordinate frame by generalized Procrustes analysis （GPA）. The age estimation model was established by partial least square regression （PLSR）. Furthermore, the changes of age-correlated facial features were presented on the heat map of average face, and the reconstruction of facial images at different ages was performed based on this model.

RESULTS

With age, the average faces showed a series of changes including the nasolabial sulcus deepening, cheek sinking, cheekbone protruding and eye corner drooping. The Pearson correlation coefficient （r） between estimated age and chronological age was 0.71. The mean absolute deviation （MAD） of age estimation was 6.37 years. The results of age estimation in >30-40 years group showed a best accuracy （MAD=4.27 years）, and the deviations increased with age after 40 years. The composite facial images represented a significant result with age on facial morphological features and aging.

CONCLUSIONS

The results of this study reveal the age-correlated facial features and aging markers in Uygur population, which help to construct a reliable age estimation model.

Cathepsin D deficiency delays central nervous system myelination by inhibiting proteolipid protein trafficking from late endosome/lysosome to plasma membrane

This study aimed to investigate the role of cathepsin D (CathD) in central nervous system (CNS) myelination and its possible mechanism. By using CathD knockout mice in conjunction with immunohistochemistry, immunocytochemistry and western blot assays, the myelination of the CNS and the development of oligodendrocyte lineage cells in vivo and in vitro were observed. Endocytosis assays, real-time-lapse experiments and total internal reflection fluorescence microscopy were used to demonstrate the location and movement of proteolipid protein in oligodendrocyte lineage cells. In addition, the relevant molecular mechanism was explored by immunoprecipitation. The increase in Fluoromyelin Green staining and proteolipid protein expression was not significant in the corpus callosum of CathD-/- mice at the age of P11, P14 and P24. Proteolipid protein expression was weak at each time point and was mostly accumulated around the nucleus. The number of oligodendrocyte lineage cells (olig2+) and mature oligodendrocytes (CC1+) significantly decreased between P14 and P24. In the oligodendrocyte precursor cell culture of CathD-/- mice, the morphology of myelin basic protein-positive mature oligodendrocytes was simple while oligodendrocyte precursor cells showed delayed differentiation into mature oligodendrocytes. Moreover, more proteolipid protein gathered in late endosomes/lysosomes (LEs/Ls) and fewer reached the plasma membrane. Immunohistochemistry and immunoelectron microscopy analysis showed that CathD, proteolipid protein and VAMP7 could bind with each other, whereas VAMP7 and proteolipid protein colocalized with CathD in late endosome/lysosome. The findings of this paper suggest that CathD may have an important role in the myelination of CNS, presumably by altering the trafficking of proteolipid protein.

Role of ADH2 and ALDH2 gene polymorphisms in the development of Parkinson's disease in a Chinese population

In this study, we investigated the role of ADH2 Arg47His and ALDH2 Glu487Lys genetic polymorphisms in the development of Parkinson's disease in a Chinese population. Between January 2013 and May 2014, 115 patients with Parkinson's disease and 214 healthy controls were recruited in our study. Genotyping of ADH2 Arg47His and ALDH2 Glu487Lys polymorphisms was performed by the polymerase chain reaction-restriction fragment length polymorphism method. In the dominant model, the GA + AA genotype of ALDH2 Glu487Lys was found to be significantly associated with elevated risk of Parkinson's disease when compared with the GG genotype [odds ratio = 1.71, 95% confidence interval (CI) = 1.02-2.84]. In the recessive model, the AA genotype of ALDH2 Glu487Lys showed a 4.87-fold increase (95%CI = 1.54-18.03) in the risk of Parkinson's disease when compared to the GG and GA genotypes. However, no significant association was found between the ADH2 Arg47His polymorphism and risk of Parkinson's disease in the co-dominant, dominant, or recessive models. In conclusion, our study suggests that the ALDH2 polymorphism could influence the development of Parkinson's disease in the Chinese population studied here.

Treatment with Isorhamnetin Protects the Brain Against Ischemic Injury in Mice

Ischemic stroke is a major cause of morbidity and mortality, yet lacks effective neuroprotective treatments. The aim of this work was to investigate whether treatment with isorhamnetin protected the brain against ischemic injury in mice. Experimental stroke mice underwent the filament model of middle cerebral artery occlusion with reperfusion. Treatment with isorhamnetin or vehicle was initiated immediately at the onset of reperfusion. It was found that treatment of experimental stroke mice with isorhamnetin reduced infarct volume and caspase-3 activity (a biomarker of apoptosis), and improved neurological function recovery. Treatment of experimental stroke mice with isorhamnetin attenuated cerebral edema, improved blood-brain barrier function, and upregulated gene expression of tight junction proteins including occludin, ZO-1, and claudin-5. Treatment of experimental stroke mice with isorhamnetin activated Nrf2/HO-1, suppressed iNOS/NO, and led to reduced formation of MDA and 3-NT in ipsilateral cortex. In addition, treatment of experimental stroke mice with isorhamnetin suppressed activity of MPO (a biomarker of neutrophil infiltration) and reduced protein levels of IL-1β, IL-6, and TNF-α in ipsilateral cortex. Furthermore, it was found that treatment of experimental stroke mice with isorhamnetin reduced mRNA and protein expression of NMDA receptor subunit NR1 in ipsilateral cortex. In conclusion, treatment with isorhamnetin protected the brain against ischemic injury in mice. Isorhamnetin could thus be envisaged as a countermeasure for ischemic stroke but remains to be tested in humans.

Effects of hyperbaric oxygen on the Nrf2 signaling pathway in secondary injury following traumatic brain injury

We investigated the effects of hyperbaric oxygen treatment on the Nrf2 signaling pathway in secondary injury following traumatic brain injury, using a rat model. An improved Feeney freefall method was used to establish the rat traumatic brain injury model. Sixty rats were randomly divided into three groups: a sham surgery group, a traumatic brain injury group, and a group receiving hyperbaric oxygen treatment after traumatic brain injury. Neurological function scores were assessed at 12 and 24 h after injury. The expression levels of Nrf2, heme oxygenase 1 (HO-1), and quinine oxidoreductase 1 (NQO-1) in the cortex surrounding the brain lesion were detected by western blotting 24 h after the injury. Additionally, the TUNEL method was used to detect apoptosis of nerve cells 24 h after traumatic injury and Nissl staining was used to detect the number of whole neurons. Hyperbaric oxygen treatment significantly increased the expression of nuclear Nrf2 protein (P < 0.05), HO-1, and NQO-1 in the brain tissues surrounding the lesion after a traumatic brain injury (P < 0.05) and also significantly reduced the number of apoptotic and injured nerve cells. The neurological function scores also improved with hyperbaric oxygen treatment (P < 0.05). Therefore, hyperbaric oxygen has a neuroprotective role in traumatic brain injury, which is mediated by up-regulation of the Nrf2 signaling pathway.

Hyperbaric Oxygen Alleviates Secondary Brain Injury After Trauma Through Inhibition of TLR4/NF-κB Signaling Pathway

BACKGROUND

The aim of this study was to investigate the efficacy of hyperbaric oxygen in secondary brain injury after trauma and its mechanism in a rat model.

MATERIAL/METHODS

A rat model of TBI was constructed using the modified Feeney's free-fall method, and 60 SD rats were randomly divided into three groups--the sham group, the untreated traumatic brain injury (TBI) group, and the hyperbaric oxygen-treated TBI group. The neurological function of the rats was evaluated 12 and 24 hours after TBI modeling; the expression levels of TLR4, IκB, p65, and cleaved caspase-3 in the peri-trauma cortex were determined by Western blot; levels of TNF-α, IL-6, and IL-1β were determined by ELISA; and apoptosis of the neurons was evaluated by TUNEL assay 24 hours after TBI modeling.

RESULTS

Hyperbaric oxygen therapy significantly inhibited the activation of the TLR4/NF-κB signaling pathway, reduced the expression of cleaved caspase-3, TNF-α, IL-6 and IL-1β (P<0.05), reduced apoptosis of the neurons and improved the neurological function of the rats (P<0.05).

CONCLUSIONS

Hyperbaric oxygen therapy protects the neurons after traumatic injury, possibly through inhibition of the TLR4/NF-κB signaling pathway.

Oral administration of lactulose: a novel therapy for acute carbon monoxide poisoning via increasing intestinal hydrogen production

It has been known that the pathophysiology of carbon monoxide (CO) poisoning is related to hypoxia, the increased production of reactive oxygen species (ROS) and oxidative stress. Studies have shown that the novel, safe and effective free radical scavenger, hydrogen, has neuroprotective effects in both acute CO poisoning and delayed neuropsychological sequelae in CO poisoning. Orally administered lactulose, which may be used by some intestinal bacteria as a food source to produce endogenous hydrogen, can ameliorate oxidative stress. Based on the available findings, we hypothesize that oral administration of lactulose may be a novel therapy for acute CO poisoning via increasing intestinal hydrogen production.

Treatment with Hydrogen-Rich Saline Delays Disease Progression in a Mouse Model of Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is the most frequent adult-onset motor neuron disease, and accumulating evidence indicates that oxidative mechanisms contribute to ALS pathology, but classical antioxidants have not performed well in clinical trials. The aim of this work was to investigate the effect of treatment with hydrogen molecule on the development of disease in mutant SOD1 G93A transgenic mouse model of ALS. Treatment of mutant SOD1 G93A mice with hydrogen-rich saline (HRS, i.p.) significantly delayed disease onset and prolonged survival, and attenuated loss of motor neurons and suppressed microglial and glial activation. Treatment of mutant SOD1 G93A mice with HRS inhibited the release of mitochondrial apoptogenic factors and the subsequent activation of downstream caspase-3. Furthermore, treatment of mutant SOD1 G93A mice with HRS reduced levels of protein carbonyl and 3-nitrotyrosine, and suppressed formation of reactive oxygen species (ROS), peroxynitrite, and malondialdehyde. Treatment of mutant SOD1 G93A mice with HRS preserved mitochondrial function, marked by restored activities of Complex I and IV, reduced mitochondrial ROS formation and enhanced mitochondrial adenosine triphosphate synthesis. In conclusion, hydrogen molecule may be neuroprotective against ALS, possibly through abating oxidative and nitrosative stress and preserving mitochondrial function.

Protein expression levels in the medullary visceral zone of rats with subarachnoid hemorrhage

We investigated protein expression in the medullary visceral zone (MVZ) of rats with multiple-organ dysfunction syndrome (MODS) caused by subarachnoid hemorrhage (SAH) to discuss the possible regulatory mechanism of the MVZ in the course of SAH-induced MODS. A SAH-induced MODS model was established in rats by injecting arterial blood into the Willis' circle. Protein expression in the MVZ was analyzed by immunohistochemistry assay. Protein expression in the MVZ peaked 24-36 h after SAH, and was significantly higher than in the control and sham operation groups. Organs at each time point exhibited inflammatory injuries to varying degrees after SAH, which reached a maximum at 24-36 h. Incidences of systemic inflammatory response syndrome and MODS were 100 and 71.67%, respectively, after SAH. There is a consistency between MVZ protein expression and inflammatory changes in each organ after SAH. This prompts the suggestion that the MVZ may be one of the direct regulative centers in SAH-induced MODS, and may be involved in the functional regulation of the surrounding organs after SAH.

A new method to induce myasthenia gravis models and the protective effect of soluble decay accelerating factors

It is expensive to induce experimental autoimmune myasthenia gravis (EAMG) by active immunity, and difficult to obtain natural acetylcholine receptor (AChR). We sought a new method of inducing EAMG by immunizing rats with artificially synthesized AChR. The AChR mRNA in TE671 cells was extracted and reverse transcribed. The inclusion body was purified and protein concentration was determined, and the EAMG animal model was used for induction. The serum was extracted from rat blood. The antibody titer was determined using enzyme-linked immunosorbant assay (ELISA). The concentration of decay accelerating factor (DAF) in the rat serum was determined by ELISA, and the metabolism of serum rDAF was determined by western blot. We evaluated the inhibition of rDAF by determining the 50% complement hemolysis unit in the rat serum. The extracellular domain (ECD) nucleotide sequence clone produced by polymerase chain reaction was completely consistent with that in the human gene bank; it was induced by isopropyl β-D-1-thiogalactopyranoside to express the protein after insertion into vector pET16b. Sodium dodecyl sulfate polyacrylamide gel electrophoresis demonstrated that the inclusion body protein was the exact target. The ECD protein was able to bind with mAb35 after dialysis and renaturation, which demonstrated protein activity. The soluble ECD protein was used to immunize rats and obtain the EAMG models. The inhibitory effect of the complement was unsatisfactory owing to high decay rate after rDAF injection into the EAMG models. It is easy to induce the EAMG model by obtaining the AChRTEα1 subunit ECD protein using the substitution method.

High plasma glutamate levels are associated with poor functional outcome in acute ischemic stroke

The aim of the present study was to investigate the relationship between acute ischemic stroke and glutamate levels and to determine the prognosis value of plasma glutamate levels to predict the functional outcome. Two hundred and forty-two patients with acute ischemic stroke and 100 sex- and age-matched controls were included in the study. Plasma glutamate levels were determined by HPLC at admission in both groups. Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS). The modified Rankin Scale (mRS) scores at 3 months was determined to outcomes, and unfavorable outcomes were defined as mRS at 3-6. The prognostic value analyzed by logistic regression analysis, after adjusting for the possible confounders. In the 94 patients with an unfavorable functional outcome, plasma glutamate levels were higher compared with those in patients with a favorable outcome [221(IQR, 152-321) μM; 176(IQR, 112-226) μM, respectively; P < 0.0001). In multivariate logistic regression analysis, glutamate was an independent predictor of functional outcome, with an adjusted OR of 6.99 (95 % confidence interval [CI] 2.21-21.23). Receiver operating characteristics to predict functional outcome demonstrated areas under the curve of glutamate of 0.821 (95 % CI 0.733-0.878; P < 0.0001) and combined model (glutamate and NIHSS) improved the NIHSS score alone. Plasma glutamate levels can be seen as an independent short-term prognostic marker of functional outcome in Chinese patients with acute ischemic stroke even after correcting for possible confounding factors.

Valproic acid attenuates the suppression of acetyl histone H3 and CREB activity in an inducible cell model of Machado-Joseph disease

Machado-Joseph disease (MJD) is caused by a (CAG)n trinucleotide repeat expansion that is translated into an abnormally long polyglutamine tract. This disease is considered the most common form of spinocerebellar ataxia (SCA). In the present study, we developed stable inducible cell lines (PC12Tet-On-Ataxin-3-Q28/84) expressing ataxin-3 with either normal or abnormal CAG repeats under doxycycline control. The expression of acetyl histone H3 and the induction of c-Fos in response to cAMP were strongly suppressed in cells expressing the protein with the expanded polyglutamine tract. Treatment with valproic acid, a histone deacetylase inhibitor (HDACi), attenuated mutant ataxin-3-induced cell toxicity and suppression of acetyl histone H3, phosphorylated cAMP-responsive element binding protein (p-CREB) as well as c-Fos expression. These results indicate that VPA can stimulate the up-regulation of gene transcription through hyperacetylation. Thus, VPA might have a therapeutic effect on MJD.

Hyperbaric oxygen therapy in rats attenuates ischemia-reperfusion testicular injury through blockade of oxidative stress, suppression of inflammation, and reduction of nitric oxide formation

OBJECTIVE

To evaluate the therapeutic utility of hyperbaric oxygen (HBO) therapy on testicular ischemia/reperfusion (I/R) injury and elucidate the underlying molecular mechanism, we tested whether HBO therapy provided rescue of the testes after torsion in rats.

METHODS

Sprague-Dawley rats were randomly divided into 4 groups: control group, control plus HBO therapy, I/R group, and I/R plus HBO therapy. The I/R model was induced by torsion of the right testis.

RESULTS

I/R in the testis resulted in disrupted seminiferous tubules, germ cell-specific apoptosis, followed by a marked reduction in testis weight and daily sperm production. HBO therapy preserved seminiferous tubules, suppressed apoptosis, and prevented testicular atrophy in I/R testes. HBO therapy abated oxidative stress in I/R testes, marked by reduced malondialdehyde formation, enhanced activities of superoxide dismutase and heme oxygenase 1 (HO-1), and decreased activities of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and xanthine oxidase. HBO therapy resulted in a reduction of myeloperoxidase (MPO) activity in I/R testes, a marker of neutrophil recruitment. HBO therapy suppressed inflammation in I/R testes, marked by reduced messenger RNA (mRNA) levels of tumor necrosis factor-α (TNF-α), interleukin-1beta (IL-1β), and CD44. Furthermore, HBO therapy suppressed the activation of nuclear factor kappa B (NFκB), p38, and c-JUN-N-terminal kinase (JNK) signaling pathways in I/R testes. In addition, HBO therapy reduced nitric oxide formation in I/R testes through suppression of inducible nitric oxide synthase and dimethylarginine dimethylaminohydrolase.

CONCLUSION

HBO therapy in rats attenuated I/R-induced testicular injury, possibly through abating oxidative stress, suppressing inflammation, and reducing nitric oxide formation.

Proteomic identification of differentially expressed proteins in curcumin-treated MCF-7 cells

Curcumin (CM), a well-known dietary pigment derived from Curcuma longa L., possess anticancer activities against a variety of tumors including human breast carcinoma. In combination with docetaxel, CM has been used in breast cancer management in the clinic. In order to explore the possible mechanism of anticancer activity of CM, in the present study, we aimed to identify proteins involved in the anticancer activity of CM in human breast cancer cell line MCF-7 using the two-dimensional electrophoresis (2-DE)-based proteomic analysis. MCF-7 cells were cultured at 37°C in an atmosphere of 5.0% CO(2). All the following experiments were repeated three times. Cell viability assay showed that after a 48-h incubation CM dose-dependently inhibited cell growth with an IC(50) value of 47.42 μM. Treatment of CM at 47.42 μM for 48 h induced apoptosis as determined by nuclear morphologic changes of Hoechst stained cells and flow cytometric analysis of Annexin V-FITC/PI stained cells. Proteomic analysis identified 12 differentially expressed proteins which contributed to multiple functional activities such as DNA transcription, mRNA splicing and translation, amino acid synthesis, protein synthesis, folding and degradation, lipid metabolism, glycolysis, and cell motility. Among them 7 proteins were up-regulated and 5 down-regulated. The up-regulated ones were verified by quantitative real-time PCR. The down-regulated proteins, TDP-43, SF2/ASF and eIF3i, as well as up-regulated ones, 3-PGDH, ERP29, and platelet-activating factor acetylhydrolase IB subunit beta positively contribute to the anticancer activity of CM in MCF-7 cells. These molecules are implicated in the bioactivities of CM for the first time. The findings of this study would shed new insights for systematically understanding the mechanisms of CM in breast cancer intervention.

Identification of differentially expressed genes in the growth plate of broiler chickens with thiram-induced tibial dyschondroplasia

Tibial dyschondroplasia (TD) is characterized by expansion of the proximal growth plates of the tibiotarsus that fail to form bone, lack blood vessels, and contain non-viable cells. Thiram (a carbamate pesticide), when fed to young broiler chicks, induces TD with high regularity and precision. We used this experimental model to understand the cause of the defects associated with TD by selecting and identifying the genes differentially expressed in the TD growth plate of broiler chickens. Broiler chicks at 7 days of age were randomly divided into two groups. After fasting overnight, they were fed with regular diet (control) or the same diet containing 100 mg/kg thiram for 96 h to induce TD (thiram-fed). mRNA was purified from the growth plates of control and thiram-fed broilers. Forward and reverse-subtracted cDNA libraries were generated by suppression subtractive hybridization technology. Ten selected genes from cDNA libraries were identified by real-time quantitative polymerase chain reaction. All were differentially expressed in TD growth plates (P<0.05 or P<0.01). The levels of collagen type X (Col X), pro-alpha-1 collagen type I (Col I alpha1), collagen type IX (Col IX), NADH dehydrogenase (NADH DH), cytochrome C oxidase subunit III (COX III), enolase 1, alpha (ENO1), carbonic anhydrase II (CA2) and heat shock protein 90 (Hsp90) mRNA transcripts were up-regulated, while the expression levels of Matrilin 3 (MATN3) and chondromodulin-I (ChM-I) were down-regulated. Col I and Hsp90 were detected by immunohistochemistry at different stages. Given that these genes are involved in matrix formation, endochondral ossification, developmental regulation, electron transport in the mitochondrial respiratory chain and vascularization, our findings may provide new insights into understanding the pathogenesis of TD.

Evaluation of acute bis(7)-tacrine treatment on behavioral functions in 17-day-old and 30-day-old mice, with attention to drug toxicity

Bis(7)-tacrine was evaluated for efficacy on memory retention in mice 17 days of age and 30 days of age. The tests used were a passive-avoidance response test and a measure of spontaneous motor activity. Also, possible drug-induced hepatotoxicity and acute drug toxicity were evaluated. Behavioral studies were performed using a step-through task and an open-field test with a 24-h interval between training and evaluation tests. Bis(7)-tacrine (0.06-20 micromol/kg) was subcutaneously injected 30 min prior to the first session of both test types. During the training session of the step-through task, bis(7)-tacrine treatment reduced (by 46%, P<0.01) the number of avoidable electric shocks (footshocks) only at a high dose of 20 micromol/kg in mice 17 days of age, but dose-dependently decreased the number of footshocks (10-56%, P<0.001) in mice 30 days of age. Bis(7)-tacrine treatment at all doses tested did not produce any detectable changes in retention latency in mice 17 days of age, but the drug significantly prolonged retention latency at low doses (1.25 and 2.50 micromol/kg), and not high doses (5-20 micromol/kg), in mice 30 days of age. In the open-field test, bis(7)-tacrine decreased spontaneous motor activity in the acquisition session only at a high dose of 20 micromol/kg in mice 17 days of age and 30 days of age (by 28 and 45%, respectively), but did not affect spontaneous motor activity in the recall session. Bis(7)-tacrine treatment at a dose of 20 micromol/kg produced a more potent hepatotoxic effect in mice 30 days of age than in mice 17 days of age, (P<0.05), and the drug caused acute toxicity with comparable potencies in mice of both age groups. In conclusion, mice 30 days of age seemed to be more sensitive than mice 17 days of age to bis(7)-tacrine-induced cognitive function enhancement and hepatotoxicity. Bis(7)-tacrine appears to be more potent and more selective as a cognitive function-enhancing agent than tacrine.

Evaluation of acute tacrine treatment on passive-avoidance response, open-field behavior, and toxicity in 17- and 30-day-old mice

The potential of tacrine in altering cognitive/behavioral function as well as in causing toxicity was evaluated in mice of 17 and 30 days of age. Cognitive and behavioral studies were performed using a step-through passive avoidance task and a habituation open-field test with a 24-h retention interval. Tacrine was subcutaneously injected (1.25-80 micro mol/kg) 30 min prior to the first session of both tests. During the training session in step-through task, tacrine treatment dose-dependently decreased the number of footshocks, with IC(50) values being 7.8 and 23.3 micro mol/kg in 17- and 30-day-old mice, respectively. Treatment with tacrine at a low dose (5 micro mol/kg) significantly prolonged the retention latency in 17-day-old mice only, but it shortened the retention latency at high doses of 20 and 40 micro mol/kg in 17- and 30-day-old, respectively. During the acquisition session in the open-field test, tacrine treatment dose-dependently decreased the locomotor activity in 17- and 30-day-old mice, with IC(50) values being 15.1 and 24.7 micro mol/kg, respectively. High doses of tacrine invariably increased the locomotor activity during the recall session. Tacrine treatment at a dose of 40 micro mol/kg caused a significant increase in serum alanine aminotransferase activity in 17- and 30-day-old mice at 6 h post-dosing, with the extent of stimulation in 30-day-old mice being more prominent. In conclusion, tacrine was more potent in enhancing/disrupting the cognitive function, inhibiting locomotor activity as well as in causing hepatotoxicity in 17-day-old than in 30-day-old mice.

Trends in childhood injury mortality in Canada, 1979-2002

OBJECTIVE

To examine national trends in mortality rates for injuries among Canadian children younger than 15 years in 1979-2002.

METHODS

Data on injury deaths were obtained from the Canadian Vital Statistics system at Statistics Canada. Injuries were classified using the codes for external cause of injury and poisoning (E-codes) by intent and by mechanism. Mortality rates were age adjusted to the 1990 world standard population. Negative binomial regression was used to estimate the secular trends.

RESULTS

Annual mortality rates for total and unintentional injuries declined substantially (from 23.8 and 21.7 in 1979 to 7.2 and 5.8 in 2002, respectively), whereas suicide deaths among children aged 10-14 showed an increasing trend. All Canadian provinces and territories showed a decreasing trend in mortality rates of total injuries. Motor vehicle related injuries were the most common cause of injury deaths (accounted for an average of 36.4% of total injury deaths), followed by suffocation (14.3%), drowning (13.5%), and burning (11.1%); however, suffocation was the leading cause for infants. The number of potential years of life lost due to injury before age 75 decreased from 89 343 in 1979 to 27 948 in 2002 for children aged 0-14 years.

CONCLUSIONS

During the period 1979-2002, there were dramatic decreases in childhood mortality for total injuries and unintentional injuries as well as various degrees of reduction for all causes of injury except suffocation in children aged 10-14 years and drowning in infants. The reason for the reduction in injury mortality might be multifactoral.

Comparison of the Inhibitory Efficacy of Four Belladonna Drugs on Gastrointestinal Movement and Cognitive Function in Food-Deprived Mice

Belladonna drugs, scopolamine (Sco), atropine (Atr), anisodine (AT(3)), and anisodamine (Ani), frequently used for gastrointestinal motility disorders often produce adverse effects on the central nervous system. In the present work, these drugs (0.05, 0.5, 5, and 50 micromol kg(-1), i.p.) were evaluated for their potential to inhibit gastrointestinal motility and cognition in mice. Results showed that the maximum inhibitory rates of Sco, Atr, AT(3), and Ani on gastric emptying and small intestinal movement were 29.78, 40.69, 12.30, and 17.99% and 51.98, 58.46, 46.51, and 46.22%, respectively. The affinities of Sco, Atr, AT(3), and Ani for muscarinic receptors in the whole mice were 1.62, 1.48, 2.28, and 1.11 micromol kg(-1) for the stomach or 0.30, 1.12, 0.59, and 1.14 micromol kg(-1) for the small intestine, respectively. The minimal effective doses for impairing avoidance-response learning were 5 micromol kg(-1) for Sco, Atr, or AT(3) and 50 micromol kg(-1) for Ani. The initial doses for insulting the avoidance-response memory or open-field memory were 0.5, 5, 5, and 50 micromol kg(-1) or 5, 5, 5, and >50 micromol kg(-1) for Sco, Atr, AT(3), and Ani, respectively. We conclude that the relative susceptibility of the mouse's tissue or function capacities towards the inhibitory effects of belladonna drugs is small intestine > stomach > avoidance-response memory > avoidance-response learning > open-field memory.

Atomistics of Ge deposition on Si(100) by atomic layer epitaxy

Chlorine termination of mixed Ge/Si(100) surfaces substantially enhances the contrast between Ge and Si sites in scanning tunneling microscopy observations. This finding enables a detailed investigation of the spatial distribution of Ge atoms deposited on Si(100) by atomic layer epitaxy. The results are corroborated by photoemission measurements aided by an unusually large chemical shift between Cl adsorbed on Si and Ge. Adsorbate-substrate atomic exchange during growth is shown to be important. The resulting interface is thus graded, but characterized by a very short length scale of about one monolayer.

Schisandrin B protects against tacrine- and bis(7)-tacrine-induced hepatotoxicity and enhances cognitive function in mice

Intragastric administration (100-200 micromol/kg) of tacrine (THA) or bis(7)-THA could cause an acute and dose-dependent increase in plasma alanine aminotransferases activity in mice at 6 h after the drug administration. The increase in plasma enzyme activity was associated with an increase in hepatic malondialdehyde level, an indirect index of oxidative tissue damage. Pretreating mice with schisandrin B (Sch B), an active dibenzocyclooctadiene derivative isolated from the fruit of Schisandra chinensis, at a daily dose of 0.125-0.5 mmol/kg for 3 days protected against the THA/bis(7)-THA induced hepatic oxidative damage in a dose-dependent manner. Sch B treatment (0.025-0.5 mmol/kg/day x 5) also enhanced the passive avoidance-response in mice as assessed by the step-through task experiment. The ensemble of results suggests that Sch B may be useful for reducing the potential hepatotoxicity of THA/bis(7)-THA in anti-Alzheimer's therapy.

Learning deficits induced by 4 belladonna alkaloids are preferentially attenuated by tacrine

AIM

To examine the antagonism of tacrine on the amnesic effects of scopolamine (Sco), anisodine (AT3), atropine (Atr), and anisodamine (Ani).

METHODS

Cognitive functions and locomotor activities were determined using two sessions of step-through and open-field tests, respectively. Mice were injected with one of the belladonna alkaloids (0.05-50 mumol.kg-1, i.p.) and tacrine (50 mumol.kg-1, s.c.) 30 min before the first session.

RESULTS

Tacrine completely blocked the avoidance-learning deficit caused by Sco 0.5 mumol.kg-1, AT3 and Atr 5 mumol.kg-1, or Ani 50 mumol.kg-1. But tacrine partly antagonized the learning deficit induced by Sco 5-50 mumol.kg-1 or Atr and AT3 50 mumol.kg-1. The avoidance-memory deficit caused by Sco 0.05-5 mumol.kg-1 or Atr 5 mumol.kg-1 was completely or partly attenuated by tacrine, which did not antagonize the memory deficit elicited by Sco and Atr 50 mumol.kg-1, AT3 5 and 50 mumol.kg-1, and Ani 50 mumol.kg-1. During the acquisition, the locomotor activity of the mice was inhibited by tacrine. This reduction was completely antagonized by Sco 0.5-50 mumol.kg-1, AT3 5-50 mumol.kg-1, Atr 5-50 mumol.kg-1, and only partly antagonized by AT3 and Atr 0.5 mumol.kg-1 or Ani 50 mumol.kg-1.

CONCLUSION

Compared with the avoidance-memory deficit, the avoidance-learning deficit caused by belladonna alkaloids is more preferentially attenuated by tacrine.

Belladonna alkaloids-induced behavioral changes and amnesia on open-field and step-through in 18-, 28-, and 38-day-old mice

AIM

To study the age-related changes of atropine (Atr), scopolamine (Sco), anisodine (AT3), and anisodamine (Ani) on behaviors and memories.

METHODS

The behaviors and memories were measured with open-field test and step-through task. M-cholinergic receptors were determined by [3H] quinuclidinyl benzilate ([3H] QNB).

RESULTS

During acquisition session (d 1) the 18-, 28-, and 38-d-old mice pretreated with Atr, Sco, and AT3 (0.02, 0.2, 2, or 20 mg.kg-1, i.p.) in open-field test showed increase in walking counts by 26%-42%, but decrease in rearing, grooming, and defecating counts for 50%-92%, 67%-100%, and 75%-100%, respectively. On recall session (d 2) the walking and rearing behaviors in the 18- and 28-d-old mice receiving Atr, Sco, and AT3 on d 1 were higher than those in the mice receiving saline. But a lower grooming behavior on d 2 was found in the mice receiving the drugs on d 1. On d 1 Ani 20 mg.kg-1 reduced the rearing behavior by 50% in 18-d-old mice and defecation by 33%-36% in 18- and 28-d-old mice. All the 4 belladonna alkaloids increased the number of avoidance-response errors and decreased the retention latencies in step-through task. Bmax of [3H] QNB binding sites in frontal cortex and hippocampus regions in the 38-d-old mice increased 7% and 23% vs in the mice of 18 d of age, respectively.

CONCLUSION

1) The effects of the belladonna alkaloids on behaviors and memories in adult mice were weaker than those in young mice. 2) The belladonna alkaloids-induced amnesia on passive avoidance-response in step-through was more sensitive than behavioral changes and amnesia on open-field. 3) According to the lowest effective doses which insulted the behaviors or memories in young mice, Sco was about 10, 100, and 1000 times more potent than Atr, AT3, and Ani, respectively.

Features of memory on novel situation and avoidance response: evidence from comparisons between open-field behavior and step-through task

AIM

To study the features of memory on novel situation and avoidance response in mice.

METHODS

Open-field activity and step-through latency were used to determine the memory of mice on a new environment and avoidance, respectively.

RESULTS

The open-field memory was only observed 24 and 48 h after acquisition session. The avoidance memory still existed 72 and 96 h after training session. On d 1 mice were allowed to remain on open-field and step-through for 0.5, 1, 3, and 5 min. On d 2 the retention latencies in 0.5- and 1-min groups were shorter than those in 3- and 5-min groups, while the recall activities in open-field were indifferent between these groups. Scopolamine (1 mg.kg-1) and caffeine (200 mg.kg-1) injected ip 15 min before the first session inhibited the avoidance response and the adaptation to open-field environment in mice. Chlorpromazine, promethazine, picrotoxin and pentobarbital impaired the avoidance memory, but not impaired the open-field memory.

CONCLUSION

These results supported the hypothesis that the adaptation of mice on open-field was a short or medium term memory.

Circadian effects of scopolamine on memory, exploratory behavior, and muscarinic receptors in mouse brain

Mice were maintained at light-dark cycle with lights on from 05:00-19:00 for 10 d in laboratory. The study was performed at 07:00-09:00, 15:00-17:00, and 21:00-23:00 in June and July. Scopolamine (Scop, 0.1 and 0.4 mg.kg-1, ip) was injected 15 min prior to training or the first exploratory test. The amnesic effects of Scop showed hyperresponses at 07:00-09:00 and 15:00-17:00, and hyporesponses at 21:00-23:00 using step-through and step-down tasks. The circadian effects of Scop on exploratory behavior were consistent with the findings above mentioned. The numbers of [3H]quinuclidinyl benzilate ([3H]QNB) binding sites in the temporal cortex and hippocampus were more at 08:00 and 16:00 than those at 22:00. However, muscarinic receptor levels in the striatum were lower at 08:00 than those at 22:00. These results indicated that the effects of Scop on memory, behavior in a novel environment, and muscarinic receptors in brain regions showed circadian changes in mice.

Acetylcholine contents and muscarinic receptor levels in frontal cortex, corpus striatum, and hippocampus of reserpinized rats and mice

The acetylcholine (ACh) levels in rat and mouse frontal cortex increased 155% and 124%, respectively, 24 h after ip reserpine 3 mg.kg-1. Striatal ACh contents, however, were diminished by 47% in rats and 80% in mice. ACh contents elevated 50% and scopolamine (Scop) depleted the ACh by 47% in mouse striatum 12 h following reserpine. Receptor binding assay showed that 24 h after reserpine the Bmax of [3H]quinuclidinyl benzilate ([3H]QNB) binding to muscarinic receptors increased in frontal cortex (by 33% in rats, by 30% in mice) and decreased in striatum (31% in rats, 26% in mice). In mouse hippocampus the ACh contents, Bmax, and affinity of muscarinic receptors lowered 63%, 19%, and 26%, respectively. But these changes were not seen in rat hippocampus.

[Influences of intraventricular injection of 6-hydroxydopamine on passive-avoidance response, acetylcholine, and muscarinic receptors in mouse brain]

In step-through and step-down tasks, icv 6-hydroxydopamine (6-OHDA) 20 micrograms on d 14 before training impaired the learning and memory processes in mice. But the amnesic effects in mice received icv 6-OHDA were overcome by ip scopolamine (Scop) 0.5 mg.kg-1 at 15 min before trial. When mice were pretreated with icv 6-OHDA the content of acetylcholine (ACh) in the brain showed no change, whereas the ACh-depleting action of Scop (2 mg.kg-1) was diminished. [3H]Quinuclidinyl benzilate binding assay indicated that the brain muscarinic receptor density (Bmax) and Kd in the mice after icv 6-OHDA were respectively decreased 48% and 57% as compared to the icv sterile water group. These findings suggested a possible participation of brain cholinergic nervous system in memory impairment induced by icv 6-OHDA in mice.

[Circadian changes of acetylcholine, choline acetyltransferase, acetylcholinesterase and muscarinic receptors in mouse brain]

By means of radioisotope, the daily changes of cholinergic nervous markers, acetylcholine (ACh), choline acetyltransferase (ChAT), acetylcholinesterase (AChE) and muscarinic receptors in the mouse brain were measured in September and October. The mice were housed 5 animals to a cage under natural light-dark cycle (12 : 12) for 7 d in the laboratory room at 18-22 degrees C. The determinations of ACh were taken, every 2 h, to assess the brain ACh of 5 mice for 24 consecutive hours. M-cholinergic receptors, ChAT and AChE activity were examined at 10:00, 16:00 and 22:00. The results demonstrated that the ACh contents, ChAT activity and muscarinic receptor Bmax value were high at 10:00, low at 16:00 and 22:00. However, AChE maximum activity was found at 16:00, minimum activity at 22:00. But the affinity of muscarinic receptors to [3H]QNB did not show any significant daily changes. These data strongly suggested that in mouse brain the cholinergic nervous markers showed a clear daily rhythm.

[The antipyretic, hypothermal and sedative activities of mieyanling]

Mieyanling has an antipyretic effect on the fever of animals caused by yeast or TAB vaccine. The hypothermal effect of Mieyanling on the temperature of normal mice and rats was also observed. The ED50 of antipyretic and hypothermal action of this drug in mice was 20g/kg and 50g/kg respectively. There was a CNS depressive effect when Mieyanling was administered 60g/kg orally to mice.