Healthcare providers' perceived barriers to providing breastfeeding support in Northwest rural China

BACKGROUND

Healthcare providers play important roles in supporting breastfeeding. Although there has been insufficient actual breastfeeding support from healthcare providers in China, little research has been conducted to understand Chinese healthcare providers' perceived barriers to providing breastfeeding support, especially in rural China. This study aims to identify these perceived barriers to providing breastfeeding support in Northwestern rural China.

METHODS

This study was conducted during the period from March 2018 to December 2018. Forty-one healthcare providers were recruited through purposive sampling in two rural counties in Northwest China that are in close proximity to each other and share similar demographic features. Participants included obstetrician-gynecologists, midwives, nurses, "village doctors", and township and village maternal and child health workers. Qualitative data were collected through one-on-one in-depth semi-structured interviews and focus group discussions. Transcripts were thematically analyzed.

RESULTS

Analysis of interview data resulted in four themes that the participants perceived as barriers to supporting breastfeeding: (1) lack of medical resources, within which inadequate staffing, and lack of financial incentives were discussed, (2) lack of clear and specific responsibility assignment, within which no one takes the lead, and mutual buck-passing were discussed, (3) healthcare providers' lack of relevant expertise, within which lack of knowledge and skills, and low prestige of village healthcare providers were discussed, (4) difficulties in accessing mothers, within which medical equipment shortages reduce services utilization, mothers' housing situation, mothers' mobility, and cultural barriers were discussed.

CONCLUSIONS

The study identified HCPs perceived barriers to providing breastfeeding support. Unique to China's Tri-Level Healthcare System, challenges like staffing and financial incentives are hard to swiftly tackle. Recommendations include mHealth enhancement and clarified responsibilities with incentives and tailored training. Further research is crucial to evaluate these strategies in rural Northwestern China and comparable underdeveloped areas nationwide.

[Prevalence of frailty and associated factors among kidney transplant recipients]

Objective: To investigate the prevalence of frailty among kidney transplant recipients and to analyze the influential factors of frailty after kidney transplantation. Methods: We retrospectively included 201 kidney transplant recipients who were followed up in the Department of Urology, Beijing Chao-yang Hospital, Capital Medical University from November 2020 to May 2022. We investigated the prevalence of frailty based on the Fried Frailty Scale (including unexpected shrinking, slow walking speed, poor grip strength, low physical activity, and exhaustion). Then the logistic regression model and CART decision tree model were established separately to explore the influential factors of frailty after kidney transplantation. Results: Frail kidney transplant recipients accounted for 25.9% (n=52) of all participants. The age [M (Q₁, Q₃)] of the frailty group was higher than that of the non-frailty group, and the median ages of the two groups were 57(49, 62) and 46(38, 56) (P<0.001); the males accounted for 51.9% (n=27) and 62.4% (n=93), respectively. There was no significant difference in gender composition (P=0.244). Among the five components of Fried Frailty Scale, the incidence of unexpected shrinking was the lowest (19.4%, 39/201). In the frailty group, the frailty combination with the highest incidence was slow walking speed+low physical activity+exhaustion, which was 19.2% (10/52). The logistic regression model showed that advanced age (OR=1.062, 95%CI: 1.005-1.123), history of acute rejection (OR=16.776, 95%CI: 2.288-123.028), increased neutrophil/lymphocyte ratio (NLR) (OR=2.096, 95%CI: 1.158-3.792), and comorbidity (OR=10.600, 95%CI: 1.828-61.482) were risk factors for frailty among kidney transplant recipients, and high serum albumin level (OR=0.623, 95%CI: 0.488-0.795) was a protective factor. The CART decision tree grew in three layers with four terminal nodes, and three explanatory variables were screened out: serum albumin, NLR, and age. The accuracy, sensitivity, and specificity of the logistic regression model were 87.1% (95%CI: 82.5%-91.7%), 69.2% (95%CI: 54.7%-80.9%), and 93.3% (95%CI: 87.7%-96.6%), respectively. The area under the ROC curve (AUC) of the logistic regression model was 0.951 (95%CI: 0.923-0.978). The accuracy, sensitivity, and specificity of the CART decision tree model were 91.0% (95%CI: 87.0%-95.0%), 82.7% (95%CI: 69.2%-91.3%), and 94.0% (95%CI: 88.5%-97.0%), respectively. The AUC of the CART decision tree model was 0.883 (95%CI: 0.819-0.948). Conclusions: The prevalence of frailty among kidney transplant recipients in this study is 25.9%. Advanced age, history of acute rejection, low serum albumin level, increased NLR, and comorbidity are likely to be associated with the long-term frailty among kidney transplant recipients.

[Clinical value of a differentiation prediction model for invasive lung adenocarcinoma]

Objective: To investigate the value of predicting the degree of differentiation of pulmonary invasive adenocarcinoma (IAC) based on CT image radiomics model and the expression difference of immunohistochemical factors between different degrees of differentiation of lesions. Methods: The clinicopathological data of patients with pulmonary IAC confirmed by surgical pathology in the Affiliated Huai'an First People's Hospital to Nanjing Medical University from December 2017 to September 2018 were collected. High-throughput feature acquisition was performed for all outlined regions of interest, and prediction models were constructed after dimensionality reduction by the minimum absolute shrinkage operator. Receiver operating characteristic curve was used to assess the predictive efficacy of clinical characteristic model, radiomics model and individualized prediction model combined with both to identify the degree of pulmonary IAC differentiation, and immunohistochemical expressions of Ki-67, NapsinA and TTF-1 were compared between groups with different degrees of IAC differentiation using rank sum test. Results: A total of 396 high-throughput features were extracted from all IAC lesions, and 10 features with high generalization ability and correlation with the degree of IAC differentiation were screened. The mean radiomics score of poorly differentiated IAC in the training group (1.206) was higher than that of patients with high and medium differentiation (0.969, P=0.001), and the mean radiomics score of poorly differentiated IAC in the test group (1.545) was higher than that of patients with high and medium differentiation (-0.815, P<0.001). The differences in gender (P<0.001), pleural stretch sign (P=0.005), and burr sign (P=0.033) were statistically significant between patients in the well and poorly differentiated IAC groups. Multifactorial logistic regression analysis showed that gender and pleural stretch sign were related to the degree of IAC differentiation (P<0.05). The clinical feature model consisted of age, gender, pleural stretch sign, burr sign, tumor vessel sign, and vacuolar sign, and the individualized prediction model consisted of gender, pleural stretch sign, and radiomic score, and was represented by a nomogram. The Akaike information standard values of the radiomics model, clinical feature model and individualized prediction model were 54.756, 82.214 and 53.282, respectively. The individualized prediction model was most effective in identifying the degree of differentiation of pulmonary IAC, and the area under the curves (AUC) of the individualized prediction model in the training group and the test group were 0.92 (95% CI: 0.86-0.99) and 0.88 (95% CI: 0.74-1.00, respectively). The AUCs of the radiomics group model for predicting the degree of differentiation of pulmonary IAC in the training group and the test group were 0.91 (95% CI: 0.83-0.98) and 0.87 (95% CI: 0.72-1.00), respectively. The AUCs of the clinical characteristics model for predicting the degree of differentiation of pulmonary IACs in the training and test groups were 0.75 (95% CI: 0.63-0.86) and 0.76 (95% CI: 0.59-0.94), respectively. The expression level of Ki-67 in poorly differentiated IAC was higher than that in well-differentiated IAC (P<0.001). The expression levels of NapsinA, TTF-1 in poorly differentiated IAC were higher than those in well-differentiated IAC (P<0.05). Conclusions: Individualized prediction model consisted of gender, pleural stretch sign and radiomics score can discriminate the differentiation degree of IAC with the best performance in comparison with clinical feature model and radiomics model. Ki-67, NapsinA and TTF-1 express differently in different degrees of differentiation of IAC.

[Effects of high protein diet on anthropometric indices and blood lipid in overweight and obese children: a Meta-analysis]

Objective: To evaluate the effects of a high-protein diet on anthropometric indices and blood lipid in overweight and obese children and provide evidence for their dietary management. Methods: This was a Meta-analysis. The randomized controlled trials on the effects of a high-protein diet on anthropometric indices and blood lipid in overweight and obese children published up to January 19, 2022 were searched in PubMed, Web of Science, Embase, Cochrane Library and CNKI database, with the key words of "child" "adolescent" "obesity" "overweight" "pediatric obesity" "weight loss" "dietary protein" "dietary carbohydrate" "caloric restrict" both in English and Chinese. The quality of the included literature was evaluated according to the "risk of bias" assessment tool, which included bias from the randomization process, deviation from intended interventions, missing outcome data, measurement of the outcome and selection of the reported results. Moreover, calculated the pooled mean difference, perform heterogeneity test, and assess publication bias. Results: A total of 8 articles were selected from the retrieved 4 836 articles, all in English. The sample sizes ranged from 4 to 120. The analysis showed that the post-intervention body mass index (mean difference (MD)=-0.66, 95%CI -1.76-0.44), body mass index Z-scores (MD=-0.09, 95%CI-0.23-0.05), fat content percentage (MD=-1.07, 95%CI-2.88-0.74), high density lipoprotein (MD=0.02, 95%CI-0.02-0.06) and low density lipoprotein (MD=0.04, 95%CI-0.08-0.17) were not significantly different with those of the standard protein diet group, with P values being 0.240, 0.220, 0.250, 0.360 and 0.480, respectively. Subgroup analysis showed that after excluding one study, the difference in body mass index between the short-term intervention group and control group was statistically significant (MD=-1.60, 95%CI-3.14--0.06, P=0.040). Conclusions: A short-term high-protein diet intervention seems to improve the body mass index status of overweight and obese children. Nevertheless, a high-protein diet does not affect any other selected anthropometric indices and blood lipids. More studies with large sample sizes, higher quality and comparable standard of high-protein diet are needed for further demonstration.

[Current status and prospects of studies on biological occupational hazards]

Biological occupational hazards have occurred frequently for a long time, which have seriously affected the health of relevant occupational groups. The infection of medical staff caused by improper occupational protection in public health emergencies also sounds alarms to practitioners with biological hazards. In order to further carry out the research work of biological occupational hazards, this paper combs and summarizes the research status of biological occuational hazards in agriculture, forestry, animal husbandry, fishery and other industries, and puts forward suggestions for in-depth research from three aspects of research scope, research methods and research contents, to provide some reference for the development of biological occupational hazards research in the future.

[Expressions of MPV, P-LCR and NLR in patients with novel coronavirus disease 2019]

To provide new ideas for clinical diagnosis and treatment of coronavirus disease 2019 (COVID-19), this study explore the expression level and prognostic value of platelet parameters in mild, moderate and severe COVID-19. This is a retrospective analysis. From January to May 2020, a total of 69 patients who were diagnosed with COVID-19 in the Third Central Hospital and the Jinnan Hospital (both situated in Tianjin) were enrolled in the disease group. According to the severity, these patients were divided into mild group (15 cases), moderate group (46 cases), and severe group (8 cases). In the same period, 70 non-infected patients were enrolled in control group. The level of white blood cell count (WBC), absolute neutrophil count (NEU#), absolute lymphocyte count (LY#), neutrophil-lymphocyte ratio (NLR), red blood cell count (RBC), hemoglobin (Hb), platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), and platelet-large contrast ratio (P-LCR) before and after treatment were analyzed. Binary logistic regression analysis is used to establish a mathematical model of the relationship between these indexes and the outcome of severe COVID-19 patients. The receiver operating characteristic(ROC) curve is used to further explore the prognosis value of MPV, P-LCR, NLR separately and jointly in COVID-19 patients. Compare to the control group, WBC and NE# increase (Z=-5.63, P<0.01;Z=-9.19,P<0.01) and LY# decrease (Z=-9.34, P<0.01) in the severe group; NLR increase with the aggravation of the disease, there is significant difference between groups (Z=17.61, P<0.01); PLT, PDW, MPV and P-LCR decrease with the aggravation of the disease, there is significant difference between groups (Z=9.47, P<0.01; Z=11.41, P<0.01; Z =16.76, P<0.01; Z=13.97, P<0.01). Binary logistic regression analysis shows MPV, P-LCR and NLR have predictive value for severe COVID-19 patients. There is a negative correlation between MPV, P-LCR and severe COVID-19 patients (OR=1.004, P=0.034; OR=1.097, P=0.046). There is a positive correlation between NLR and severe COVID-19 patients (OR=1.052, P=0.016). MPV and P-LCR of patients with good prognosis after treatment were significantly higher than those before treatment (Z=-6.47, P<0.01; Z=-5.36, P<0.01). NLR was significantly lower than that before treatment (Z=-8.13, P<0.01). MPV and P-LCR in poor prognosis group were significantly lower than those before treatment (Z=-9.46, P<0.01; Z=-6.81, P<0.01). NLR was significantly higher than that before treatment (Z=-3.24, P<0.01). There were significant differences between good and poor prognosis groups before and after treatment in MPV, P-LCR and NLR (P<0.01). Combination of these three indexes, ROC shows the AUC is 0.931, the sensitivity is 91.5%, the specificity is 94.1%, the positive predictive value is 88.9%, and the negative predictive value is 87.4%, which is better than any of these indexes separately. Changes in these parameters are closely related to clinical stage of COVID-19 patients. MPV, P-LCR and NLR are of great value in the prediction and prognosis of severe COVID-19 patients.

[Exploration of omics mechanism and drug prediction of coronavirus-induced heart failure based on clinical bioinformatics]

Objective: Present study investigated the mechanism of heart failure associated with coronavirus infection and predicted potential effective therapeutic drugs against heart failure associated with coronavirus infection. Methods: Coronavirus and heart failure were searched in the Gene Expression Omnibus (GEO) and omics data were selected to meet experimental requirements. Differentially expressed genes were analyzed using the Limma package in R language to screen for differentially expressed genes. The two sets of differential genes were introduced into the R language cluster Profiler package for gene ontology (GO) and Kyoto gene and genome encyclopedia (KEGG) pathway enrichment analysis. Two sets of intersections were taken. A protein interaction network was constructed for all differentially expressed genes using STRING database and core genes were screened. Finally, the apparently accurate treatment prediction platform (EpiMed) independently developed by the team was used to predict the therapeutic drug. Results: The GSE59185 coronavirus data set was searched and screened in the GEO database, and divided into wt group, ΔE group, Δ3 group, Δ5 group according to different subtypes, and compared with control group. After the difference analysis, 191 up-regulated genes and 18 down-regulated genes were defined. The GEO126062 heart failure data set was retrieved and screened from the GEO database. A total of 495 differentially expressed genes were screened, of which 165 were up-regulated and 330 were down-regulated. Correlation analysis of differentially expressed genes between coronavirus and heart failure was performed. After cross processing, there were 20 GO entries, which were mainly enriched in virus response, virus defense response, type Ⅰ interferon response, γ interferon regulation, innate immune response regulation, negative regulation of virus life cycle, replication regulation of viral genome, etc. There were 5 KEGG pathways, mainly interacting with tumor necrosis factor (TNF) signaling pathway, interleukin (IL)-17 signaling pathway, cytokine and receptor interaction, Toll-like receptor signaling pathway, human giant cells viral infection related. All differentially expressed genes were introduced into the STRING online analysis website for protein interaction network analysis, and core genes such as signal transducer and activator of transcription 3, IL-10, IL17, TNF, interferon regulatory factor 9, 2'-5'-oligoadenylate synthetase 1, mitogen-activated protein kinase 3, radical s-adenosyl methionine domain containing 2, c-x-c motif chemokine ligand 10, caspase 3 and other genes were screened. The drugs predicted by EpiMed's apparent precision treatment prediction platform for disease-drug association analysis were mainly TNF-α inhibitors, resveratrol, ritonavir, paeony, retinoic acid, forsythia, and houttuynia cordata. Conclusions: The abnormal activation of multiple inflammatory pathways may be the cause of heart failure in patients after coronavirus infection. Resveratrol, ritonavir, retinoic acid, amaranth, forsythia, houttuynia may have therapeutic effects. Future basic and clinical research is warranted to validate present results and hypothesis.

[Effects of FoxO6 on proliferation and invasion of colorectal cancer cells]

Objective: To investigate the effects and the mechanism of FoxO6 on the proliferation and invasion of colorectal cancer cells. Methods: FoxO6 siRNA was transfected into colorectal cancer cell HCT116 and SW480. The overexpression vector pcDNA.3.1-c-Myc was constructed and co-transfected into HCT116 and SW480 cells with FoxO6 siRNA. Real-time fluorescent quantitative PCR (RT-qPCR) and western blot were used to detect the mRNA and protein expressions of FoxO6, c-Myc, and p21 in HCT116 and SW480 cells. Bromodeoxyuridine (BrdU) was used to detect cell proliferation and Transwell assay was performed to detect the invasion ability of these cells. SW480 cells transfected with FoxO6 shRNA lentivirus (LV-FoxO6) and were injected into the right armpit of BAL b/c nude mice to construct a tumor-bearing mode and the tumor volumes were measured on the days of 10, 13, 16, 19, 22, and 25 after injection. Results: The FoxO6 mRNA were 0.91±0.04, 1.72±0.07, and 2.03±0.06, and protein expression were 0.70±0.04, 1.35±0.08, and 1.56±0.07 in normal colon cell FHC, colorectal cancer cells HT116 and SW480, respectively. The protein and mRNA levels of FoxO6 in HCT116 and SW480 were significantly higher than those in FHC (both P<0.05). Knockdown of FoxO6 in HCT116 and SW480 cells decreased the mRNA and protein expressions of FoxO6 (both P<0.05), the cell proliferation ability (absorbances were 0.26±0.07 and 0.27±0.06, both P<0.05), cell invasion ability (the invaded cell numbers were 42.3±3.3 and 45.7±4.1, both P<0.05), and the mRNA and protein expressions of c-Myc, while increased the mRNA and protein expressions of p21 (both P<0.01). Overexpression of Myc in FoxO6 silenced HCT116 and SW480 cells decreased the expression of p21, while increased the cell proliferation ability (absorbances were 0.54±0.09 and 0.58±0.07, both P<0.01) and invasion ability (the invaded cell numbers were 79.2±5.9 and 80.5±6.4, both P<0.01). On the 25th day after cell inoculation in nude mice, the tumor volume of LV-FoxO6 group was (190.6±36.2) mm(3), significantly lower than (437.8.6±69.2) mm(3) of LV-NC group (P<0.05). Conclusion: FoxO6 promotes the proliferation and invasion of colorectal cancer cells through facilitating c-Myc mediated p21 expression inhibition.

Voxel-wise meta-analysis of structural changes in gray matter of Parkinson's disease patients with mild cognitive impairment

Evidence from previous voxel-based morphometry (VBM) studies indicates that widespread brain regions are involved in Parkinson’s disease with mild cognitive impairment (PD-MCI). However, the spatial localization reported for gray matter (GM) abnormalities is heterogeneous. The aim of the present study was to quantitatively integrate studies on GM abnormalities observed in PD-MCI in order to determine whether a pattern exists. Eligible whole-brain VBM studies were identified by a systematic search of articles in PubMed and EMBASE databases spanning from 1995 to January 1, 2019. A meta-analysis was performed to investigate regional GM abnormalities in PD-MCI. The anisotropic effect size version of seed-based d mapping (AES-SDM) meta-analysis was conducted to explore the GMV differences of PD-MCI compared with PD patients with normal cognitive function (PD-NC). A total of 12 studies comprising 243 PD-MCI patients and 326 PD-NC were included in the meta-analysis. PD-MCI patients showed a robust GM decrease in the left insula and left superior temporal gyrus. Moreover, meta-regression analysis demonstrated that age, PD duration and stage, and Unified Parkinson’s Disease Rating Scale III and Mini-Mental State Examination scores might be partly correlated with the GM abnormalities observed in PD-MCI patients. The convergent findings of this quantitative meta-analysis revealed a characteristic neuroanatomical pattern in PD-MCI. The findings provide some evidence that MCI in PD may result in the breakdown of the insula and temporal gyrus, which may serve as specific regions of interest for further investigations.

[Periostin regulated by let-7/miR-98 family mediates the apoptosis and epithelial-mesenchymal transition of colon cancer]

Objective: To observe the expressions of periostin (Postn) in colon cancer tissues and cells, and to investigate its biological effect and mechanism in colon cancer cells. Methods: Real-time quantitative polymerase chain reaction (RT-qPCR) and western blot were used to detect the expressions of Postn, let-7a and miR-98 in 20 pairs of colon cancer tissues and adjacent normal tissues, colon cancer cell lines including SW480, HT-29, HCT-116 and human normal colon epithelial cell NCM460. Small interfering RNAs (siRNAs) of Postn, pcDNA3.1-Postn plasmids, let-7a mimic and its negative control let-7a mimic-NC, miR-98 mimic and its negative control miR-98 mimic-NC were transfected into HCT-116 cells. 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) was used to detect cell viability. Flow cytometry was used to detect cell apoptosis. Luciferase reporter gene assay was used to determine the targeting relationship between miRNAs and Postn. Results: Compared with adjacent normal tissues, Postn expression was up-regulated (P<0.05) while let-7a/miR-98 expression was down-regulated (P<0.05) in colon cancer tissues. Compared with NCM460 cells, Postn expression was up-regulated (P<0.05) while let-7a/miR-98 expression was down-regulated (P<0.05) in SW480, HT-29 and HCT-116 cells. In colon cancer tissues, the expression of Postn was negatively correlated with the expressions of let-7a and miR-98 (r=-0.69, P<0.001; r=-0.80, P<0.001). Inhibition of Postn in vitro reduced the viability of HCT-116 cells [(53.73±7.63)%, P<0.05], increased the apoptotic rate [(22.88±3.40)%, P<0.05], enhanced the expression of epithelial-mesenchymal transition (EMT) marker E-cadherin (2.44±0.39, P<0.05), while down-regulated the expressions of N-cadherin and Vimentin (0.44±0.07 and 0.38±0.06, P<0.05). Overexpression of Postn in vitro enhanced the cell viability of HCT-116 cells [(134.41±8.82) %, P<0.05], decreased the expression of E-cadherin (0.55±0.09, P<0.05), increased the expressions of N-cadherin and Vimentin (2.93±0.42 and 2.24±0.34, P<0.05), but had no effect on the apoptotic rate (P>0.05). Overexpression of let-7a or miR-98 partially reversed the biological effects of Postn overexpression in colon cancer cells, which implicated that Postn was a target gene of let-7a/miR-98. Conclusions: Postn is a cancer-promoting molecule of colon cancer, and inhibition of Postn expression can increase the apoptotic rate of colon cancer cells and repress EMT. Postn expression and function is regulated by let-7a/miR-98.

Short chain fatty acids contribute to gut microbiota-induced promotion of colonic melatonin receptor expression

Melatonin plays an important role in various gut functions through melatonin receptors. The gut microbiota/gut hormone axis has recently received increasing attention. However, the relationship between the gut microbiota and melatonin receptors has not yet been evaluated. We aimed to determine the effect of the gut microbiota on colonic melatonin receptor expression in germ-free (GF) rats and to further explore the potential mechanism in Caco-2 cells. In this study, GF rats were transplanted with fecal samples from a healthy human donor. Subsequently, 16S rRNA sequencing was performed to analyze the microbial communities. Colon tissue was collected for immunohistochemical analysis. The correlations between melatonin receptor expression and the gut microbiota were assessed. Melatonin receptor expression in Caco-2 cells was detected by Western blot. We found that fecal microbiota transplantation significantly increased the expression of colonic melatonin receptors in GF rats. The amount of fecal Short chain fatty acids (SCFAs) was significantly higher in fecal microbiota transplantation (FMT) rats than in GF rats. SCFA-producing bacteria, such as Alistipes and Blautia, were positively correlated with colonic melatonin receptor expression in FMT rats. Additionally, acetate and propionate significantly increased melatonin receptor-1 expression in Caco-2 cells. Therefore, the gut microbiota may promote melatonin receptor expression, and the mechanism may involve the action of SCFAs. This finding may facilitate the development of new therapeutic treatments for various gastrointestinal disorders.

[Comparative study on the display ability of CBCT and MSCT in vestibular aqueduct]

Objective: To compare the ability and visibility of cone-beam CT and MSCT in showing vestibular aqueduct. Methods: An experimental anatomical study which from June 2017 to August 2017 was performed on 76 temporal bones from 38 human cadavers with unknown clinical history. They all underwent CBCT and MSCT and all images were unified and standardized. The standard position was oblique sagital reconstruction.The length of the vestibular aqueduct, the midpoint and the external aperture width were measured on the standard position. The internal aperture, isthmus and proximal portion of the vestibular aqueduct on the images of the two kinds of equipment were evaluated. The measurement results of the two devices and image quality of the vestibular aqueduct were compared. Results: There was no significant statistical difference between the results of the measurement of CBCT and MSCT(P>0.05). In CBCT images, the total display rate of internal aperture was 77.6%(59/76), and the clearly display rate was 81.4%(48/59). The total display rate of the proximal portion of vestibular aqueduct was 57.0%(45/79), and the clearly display rate was 60.0%(27/45). The total display rate of isthmus of vestibular aqueduct was 59.2%(45/76), and the clearly display rate was 60.0%(27/45). In MSCT images, the total display rate of was 46.1%(35/76), and the clearly display rate was 60.0%(21/35). The total display rate of 5 of the proximal portion of vestibular aqueduct was 56.6%(43/76), the clearly display rate was 46.5%(20/43). The total display rate of isthmus of vestibular aqueduct was 68.4%(52/76), and the clear display rate 36.5%(19/52). There was significant statistical difference between the CBCT and the MSCT (P<0.05) in displaying of internal aperture of vestibular aqueduct. Conclusion: Compared with MSCT, the image of vestibular aqueduct obtained by CBCT can meet the diagnostic requirements and CBCT have better visibility in showing some subtle structures of vestibular aqueduct than MSCT.

[Clinical observation of postprandial hypotension in patients with hypertensive and coronary heart disease]

Objective: To explore the prevalence and clinical characteristics of postprandial hypotension(PPH) in patients with essential hypertension and coronary heart disease. Methods: A total of 197 patients with essential hypertension and coronary heart disease, who had been treated in the First Department of Cardiology of the Second Hospital of Hebei Medical University from December, 2013 to December, 2014 were included. The patients' blood pressure before breakfast, lunch and dinner and 30, 60, 90, 120 minutes after the meal were monitored. Subjects were classified into PPH group (n=37) and non-PPH group (NPPH, n=160) according to postprandial decrease in systolic blood pressure, to explore the clinical characteristics and related factors and the major adverse cardiac and cerebral vascular events of PPH. Results: Among 197 patients, 37 cases (18.8%) showed at least once postprandial decline in systolic blood pressure greater than and equal to 20 mmHg. The incidence of PPH after breakfast and dinner were higher than lunch (P<0.05). There was no significant difference in the incidence of PPH among different age groups, among patients accompanied with different diseases, and among patients with different dining position (all P>0.05). According to the baseline systolic blood pressure, patients can be divided into 4 groups(<120 mmHg, 120-129 mmHg, 130-139 mmHg, >140 mmHg), the higher the level of the baseline systolic blood pressure was, the higher the incidence of PPH was. And the incidence of major adverse cardiac and cerebral vascular events in patients during hospitalization were increased by PPH. Conclusions: The prevalence of PPH in the patients with essential hypertension and coronary heart disease is 18.8%. The incidence of PPH after breakfast and dinner is higher than lunch. The baseline systolic blood pressure is considered to be the risk factor of PPH. And PPH could lead to an increase of the incidence of major adverse cardiac and cerebral vascular events.

[Clinical characteristics of high-grade B-cell lymphomas with rearrangement of MYC, bcl-6 and bcl-2]

Objective: To investigate the clinicopathologic features of patients with high-grade B-cell lymphomas (HGBL) that have rearrangements of MYC, bcl-6 and bcl-2. Methods: One hundred and fifty-eight B-cell lymphomas patients from Institute of Hematology and Blood Diseases Hospital from January 2016 to April 2017 were detected by fluorescence in situ hybridization (FISH) with double color split-apart probes. Results: Among 158 B-cell lymphomas, 3 cases with MYC, bcl-2 and bcl-6 rearrangements were identified, 1 of which also had CCND1/IgH translocation. All three patients were of older age, with poor prognostic parameters, multiple organs involvements, elevated LDH and advanced-tumor stage. Two of the three patients were treated with high-intensity chemotherapy and had no remission with an overall survival of 9 months and 11 months respectively. One patient had follow-up with no treatment. Histologically, all three cases showed a spectrum of morphologic features. Although initially categorized as lymphoblastic lymphoma, diffuse large lymphoma and mantle cell lymphoma respectively, two cases were associated with germinal center B-cell (GCB) immunophenotype and 1 case with non-GCB immunophenotype. They had a high proliferation index as assessed by immunostaining for Ki-67 (60%-90%). Conclusions: MYC(+) bcl-2(+) bcl-6(+) HGBL is an aggressive disease with multiple organ involvement, high serum LDH levels, advanced stage disease, poor prognosis and shorter patient survival. The diagnosis should be made by histopathology combined with FISH analysis. Its separation from other types of B cell large cell lymphoma is of clinical importance.

Chronic alcohol administration affects purine nucleotide catabolism in vivo

AIMS

To investigate the relationship between chronic alcohol administration and purine nucleotide metabolism in vivo.

MAIN METHODS

Rat models of alcohol dependence and withdrawal were used. The concentrations of uric acid (UAC), urea nitrogen (UREA), creatinine (CREA), and beta-2-microglobulin (β2-M) and creatinine clearance rate (CCR) in plasma were measured. The PLC method was used to detect the absolute content of purine nucleotides in different tissues. Enzymatic activities of adenosine deaminase (ADA), xanthine oxidase (XO), ribose 5-phosphate pyrophosphokinase (RPPPK), glutamine phosphoribosylpyrophosphate amidotransferase (GPRPPAT), hypoxanthine-guanine phosphate ribose transferase (HGPRT), and adenine phosphoribosyltransferase (APRT) in the tissues were analyzed. Real-time PCR was used to determine the relative level of ADA and XO.

KEY FINDINGS

The renal function of rats with alcohol dependence was normal. Further, the content of purine nucleotides (GMP, AMP, GTP, and ATP) in tissues of the rats was decreased, which indicated that the increased uric acid should be derived from the decomposition of nucleotides in vivo. The activity of XO and ADA increased, and their mRNA expression was enhanced in the alcohol dependence group, but there was no significant difference in the activity of RPPPK and GPRPPAT in the liver, small intestine, and muscle; furthermore, no significant difference in the activity of HGPRT and APRT was observed in the brain.

SIGNIFICANCE

These results indicate that chronic alcohol administration might enhance the catabolism of purine nucleotides in tissues by inducing gene expression of ADA and XO, leading to elevation of plasma uric acid levels.

Discovery of imidazopyridazines as potent Pim-1/2 kinase inhibitors

High levels of Pim expression have been implicated in several hematopoietic and solid tumor cancers, suggesting that inhibition of Pim signaling could provide patients with therapeutic benefit. Herein, we describe our progress towards this goal using a screening hit (rac-1) as a starting point. Modification of the indazole ring resulted in the discovery of a series of imidazopyridazine-based Pim inhibitors exemplified by compound 22m, which was found to be a subnanomolar inhibitor of the Pim-1 and Pim-2 isoforms (IC₅₀ values of 0.024nM and 0.095nM, respectively) and to potently inhibit the phosphorylation of BAD in a cell line that expresses high levels of all Pim isoforms, KMS-12-BM (IC₅₀=28nM). Profiling of Pim-1 and Pim-2 expression levels in a panel of multiple myeloma cell lines and correlation of these data with the potency of compound 22m in a proliferation assay suggests that Pim-2 inhibition would be advantageous for this indication.

[Surgical treatment of ventriculoperitoneal shunt guided by ultrasound to the patients with idiopathic intracranial hypertension]

OBJECTIVE

To investigate the clinical efficacy of ventriculoperitoneal shunt treatment to patients with idiopathic intracranial hypertension.

METHODS

The clinical data of 32 patients with idiopathic intracranial hypertension who were admitted to Henan Provincial People's Hospital from August 2011 to February 2014 were collected.The underlying diseases included occlusion of the superior sagittal sinus (2 cases) and occlusion of transverse sinus (2 cases), and all 4 cases had a history of chronic otitis media.Twenty eight cases, with a history of oral contraceptive drugs (2 cases) and unclear etiology (26 cases), had normal venous sinus confirmed by imaging examination.All of 32 patients underwent ventriculoperitoneal shunt.

RESULTS

The symptoms of 32 patients such as headache, nausea, and vomiting were relieved obviously after surgery.The symptom of visual impairment of 31 cases got better in varying degrees except that 1 case went blind before operation.Besides 2 cases of loss of follow-up, the remaining 30 cases were followed up for 2 years.Thirty cases had no perioperative infection.One case had infection 1 year after operation.No one had the shunt tube blockage.

CONCLUSIONS

Patients with idiopathic intracranial hypertension should be taken active surgical treatment when drug therapy fails and could obtain satisfactory clinical curative effect by accepting treatment of ventriculoperitoneal shunt.By intraoperative ultrasound guiding lateral ventricle puncture can be achieved accurately.

[Prevention strategies for surgical complications of sphenoid wing meningiomas]

OBJECTIVE

To explore the prevention strategies for surgical complications of sphenoid wing meningiomas.

METHODS

A total of 76 cases of sphenoid wing meningiomas were included from The People's Hospital of Henan Province from 2011 to 2014. Based on the preoperative imaging data, the patients were divided into 28 cases of lateral type, 16 cases of middle type and 32 cases of medial type. According to the different characteristics of different types of sphenoid wing meningiomas, appropriate preoperative, intraoperative and postoperative measures to prevent complications were carried out.

RESULTS

A total of 2 cases of facial nerve injury occurred in 28 cases with lateral type; 1 case of intraoperative subarachnoid hemorrhage and brain swelling occurred in 16 cases with middle type; 3 cases of oculomotor nerve damage, 1 case of optic nerve injury and 4 cases of vascular injury occurred in 32 cases with the medial type. The total incidence of complications was 14.5% (11/76).

CONCLUSION

Detailed preoperative planning according to the characteristics of different types of sphenoid wing meningiomas, intraoperative use of microsurgery and Cavitron Ultrasonic Surgical Aspirator (CUSA), following the principle of in situ removal, controlling the extent of resection of tumor adhering to cavernous sinus and the great vessels, the severe surgery complications of sphenoid wing meningiomas can be reduced.

Optimization of solid-state fermentation conditions for Trichoderma harzianum using an orthogonal test

The aim of this study was to develop a protocol for the production of fungal bio-pesticides with high efficiency, low cost, and non-polluting fermentation, while also increasing their survival rate under field conditions. This is the first study to develop biocontrol Trichoderma harzianum transformants TS1 that are resistant to benzimidazole fungicides. Agricultural corn stover and wheat bran waste were used as a medium and inducing carbon source for solid fermentation. Spore production was observed, and the method was optimized using single-factor tests with 4 factors at 3 levels in an orthogonal experimental design to determine the optimal culture conditions for T. harzianum TS1. In this step, we determined the best conditions for fermenting the biocontrol fungi. The optimal culture conditions for T. harzianum TS1 were cultivated for 8 days, a ratio of straw to wheat bran of 1:3, ammonium persulfate as the nitrogen source, and a water content of 30 mL. Under optimal culture conditions, the sporulation of T. harzianum TS1 reached 1.49 x 10(10) CFU/g, which was 1.46-fold higher than that achieved before optimization. Increased sporulation of T. harzianum TS1 results in better utilization of space and nutrients to achieve control of plant pathogens. This method allows for the recycling of agricultural waste straw.

Re-expression of microRNA-375 reverses both tamoxifen resistance and accompanying EMT-like properties in breast cancer

Epithelial-mesenchymal transition (EMT) is an initiating event in tumor cell invasion and metastasis. It has been shown to occur in resistance to a range of cancer therapies, including tamoxifen. MicroRNAs (miRNAs) have been associated with EMT as well as resistance to standard therapies. To investigate the role of miRNAs in the development of resistance to tamoxifen as well as accompanying EMT-like properties, we established a tamoxifen-resistant (TamR) model by continually exposing MCF-7 breast cancer cells to tamoxifen. In addition to the molecular changes known to be involved in acquired tamoxifen resistance, TamR cells displayed mesenchymal features and had increased invasiveness. Genome-wide miRNA microarray analysis revealed that miRNA-375 was among the top downregulated miRNAs in resistant cells. Re-expression of miR-375 was sufficient to sensitize TamR cells to tamoxifen and partly reversed EMT. A combination of mRNA profiling, bioinformatics analysis and experimental validation identified metadherin (MTDH) as a direct target of miR-375. Knockdown of MTDH partially phenocopied the effects of miR-375 on the sensitivity to tamoxifen and the reversal of EMT. We observed an inverse correlation between the expression of miR-375 and its target MTDH in primary breast cancer samples, implying the pathological relevance of targeting. Finally, tamoxifen-treated patients with higher expression of MTDH had a shorter disease-free survival and higher risk of relapse. As most cancer-related deaths occur because of resistance to standard therapies and metastasis, re-expression of miR-375 or targeting MTDH might serve as potential therapeutic approaches for the treatment of TamR breast cancer.

Eating behaviour patterns in Chinese children aged 12-18 months and association with relative weight--factorial validation of the Children's Eating Behaviour Questionnaire

BACKGROUND

Eating behaviours have been suggested relating to obesity development. The Children's Eating Behaviour Questionnaire (CEBQ) is a parent-report measure constructed to assess multiple dimensions of eating behavior for children. This study aimed to test the validity of the Chinese version of Children's Eating Behaviour Questionnaire (CEBQ) in Chinese children aged 12-18 months. We examined factor structure and the reliability of the Chinese version of the CEBQ, the associations between children's eating behaviours and children's weight (BMI SDS) were assessed.

METHODS

219 questionnaires were filled out by the caregivers, approached in community health care centers in two cities in China. BMI of each child was calculated and converted to BMI SDS. Factor validation (Principal Component Analysis, exploratory factor analysis) on all CEBQ items was performed and gender difference in eating behaviours was examined. Correlations between eating behaviours and the child's BMI SDS were analyzed by linear regression analysis controlling for gender, parental combined weight, and education.

RESULTS

The factor analysis revealed a seven-factor solution, with factor 'food responsiveness' (FR) split into two. 'Satiety responsiveness' (SR) and 'Enjoyment of food' (EF) factors were not detected. Interestingly, boys scored higher than girls in the FR scales, whereas girls had a higher score in 'food fussiness' (FF) scale.

CONCLUSIONS

We conclude that although a valuable psychometric instrument, CEBQ might be affected by age and cultural differences. Therefore, adjusting it in order to fit the Chinese population was suggested. We did not find an association between eating behaviours and children's BMI SDS, when it was controlled for gender and parental weight.

MicroRNA-520/373 family functions as a tumor suppressor in estrogen receptor negative breast cancer by targeting NF-κB and TGF-β signaling pathways

MicroRNAs (miRNAs) as modulators of gene expression have been described to display both tumor-promoting and tumor-suppressive functions. Although their role has been studied in different tumor types, little is known about how they regulate nuclear factor κB (NF-κB) signaling in breast cancer. Here, we performed an unbiased whole genome miRNA (miRome) screen to identify novel modulators of NF-κB pathway in breast cancer. The screen identified 13 miRNA families whose members induced consistent effects on NF-κB activity. Among those, the miR-520/373 family inhibited NF-κB signaling through direct targeting of RELA and thus strongly reduced expression and secretion of the pro-inflammatory cytokines interleukin (IL)-6 and IL-8. With a combination of in vitro and in vivo approaches, we propose a metastasis-suppressive role of miR-520/373 family. miR-520c and miR-373 abrogated both in vitro cell invasion and in vivo intravasation of highly invasive MDA-MB-231 cells. However, knockdown of RELA did not affect their metastatic ability. mRNA profiling of MDA-MB-231 cells on overexpression of miR-520/373 members revealed a strong downregulation of transforming growth factor-β (TGF-β) signaling. Mechanistically, the metastasis-suppressive role of miR-520/373 can be attributed to direct suppression of TGFBR2, as the silencing of TGFBR2 phenocopied the effects of miR-520/373 overexpression on suppression of Smad-dependent expression of the metastasis-promoting genes parathyroid hormone-related protein, plasminogen activator inhibitor-1 and angiopoietin-like 4 as well as tumor cell invasion, in vitro and in vivo. A negative correlation between miR-520c and TGFBR2 expression was observed in estrogen receptor negative (ER(-)) breast cancer patients but not in the ER positive (ER(+)) subtype. Remarkably, decreased expression of miR-520c correlated with lymph node metastasis specifically in ER(-) tumors. Taken together, our findings reveal that miR-520/373 family has a tumor-suppressive role in ER(-) breast cancer by acting as a link between the NF-κB and TGF-β pathways and may thus contribute to the interplay of tumor progression, metastasis and inflammation.

Steroid Withdrawal Increases Risk of Acute Rejection but Reduces Infection: A Meta-Analysis of 1681 Cases in Renal Transplantation

OBJECTIVE

To evaluate the safety of steroid withdrawal in renal transplantation recipients.

METHODS

These following databases were searched: Medline (1966 to September 2005), OVID (1966 to 2004), Embase (1984 to 2004), Cochrane library (issue 4, 2005), Highwire (1849 to September 2005), American Transplant Congress (2005), Chinese Biomedicine database (CBM 1994 to 2005). The safety was measured by the following factors: patient and graft survival, acute rejection, chronic rejection, infection, serum creatinine. We performed meta-analysis by using Revman 4.2.7.

RESULTS

Nine randomized clinical trials were identified to have a steroid withdrawal and a steroid continuing group. They included 1681 patients: 845 with steroid withdrawal and 836 with continuing steroid. The risk of acute rejection after steroid withdrawal was two times higher than steroid-continuing group (RR 2.05; 95% confidence interval [CI]: 1.54, 2.72; P < .00001), while the incidence of opportunistic infection and urinary tract infection of steroid withdrawal group were lower than the control group (RR 0.80; 95%CI 0.64, 1.00; P = .05 vs RR 0.74; 95%CI, 0.60, 0.92; P = .004, respectively). The graft and patient survivals, chronic rejection, and serum creatinine were similar to the steroid continuing group.

CONCLUSION

Steroid withdrawal can significantly increase the risk of acute rejection episodes, but reduces the incidence of infection to a certain extent. To prophylaxis against serious infection, steroid withdrawal is worth considering using a sufficient immunosuppressive regimen. The key point is to balance the benefit and harm for the individual recipient.

Numerical simulation of streaming potentials due to deformation-induced hierarchical flows in cortical bone

Bone is a very dynamic tissue capable of modiA,fing its composition, microstructure, and overall geometry in response to the changing biomechanical needs. Streaming potential has been hypothesized as a mechanotransduction mechanism that may allow osteocytes to sense their biomechanical environment. A correct understanding of the mechanism for streaming potential will illuminate our understanding of bone remodeling, such as the remodeling associated with exercise hypertrophy, disuse atrophy, and the bone remodeling arounid implants. In the current research, a numerical model based on the finite element discretization is proposed to simulate the fluid flows through the complicated hierarchical flow system and to calculate the concomitant stress generated potential (SGP) as a result of applied mechanical loading. The lacunae-canaliculi and the matrix microporosity are modeled together as discrete one-dimensional flow channels superposed in a biphasic poroelastic matrix. The cusplike electric potential distribution surrounding the Haversian canal that was experimentallv observed and reported in the literature earlier was successfully reproduced by the current numerical calculation.

Projections from subnucleus oralis of the spinal trigeminal nucleus to contralateral thalamus via the relay of juxtatrigeminal nucleus and dorsomedial part of the principal sensory trigeminal nucleus in the rat

Following injection of HRP into contralateral thalamus, retrogradely labeled cells were observed in principal sensory trigeminal nucleus (Vp) and an area of juxtatrigeminal nucleus (JX) formerly described by John and Tracey (1987). When PHA-L was delivered to dorsomedial part of the subnucleus oralis (Vodm), PHA-L labeled terminals were seen in dorsomedial part of the Vp (Vpdm) and in the JX region. Comparing the distribution of PHA-L labeled terminal field with that of HRP labeled JX neurons showed that the labeled terminals and neurons were overlapped closely in the JX. The distribution patterns of the labeled terminals and JX neurons were also the same: viewed on the coronal planes caudal-rostrally, both of the labelings began to appear at the levels where the facial nerve root was just broken. Rostrally, at middle levels of the motor trigeminal nucleus (Vmo), the labelings showed their typical view covering dorsal and ventral JX (dJX, vJX). The labelings disappeared at rostral poles of the Vmo and Vp. When injections of PHA-L into the Vodm and HRP into the contralateral thalamus was made in one rat, the contacts between Vodm projecting terminals labeled with PHA-L and HRP labeled trigemino-thalamic neurons were seen in the JX and also in the Vpdm. Then, electron microscopic (EM) study was done, injections of kainic acid into the Vodm and HRP into the contralateral thalamus was performed simultaneously. After EM embedding, the JX and Vpdm regions were selected, ultrathin sections were cut and observed with EM. In both areas, axo-somatic and axo-dendritic synapses were seen between degenerated boutons and HRP labeled somata or dendrites. Namely, the Vodm projecting terminals synapsed on trigemino-thalamic neurons in the JX and Vpdm. Anyway, axo-dendritic synapses was the main type of observed synapses. Thus, the present work demonstrated 1. the JX containing a group of trigemno-thalamic neurons was a target of special projections froin the Vodm; 2. The Vodm neurons projected to the contralateral thalamus through the relay of JX and Vpdm neurons.

An approach to long-range electron transfer mechanisms in metalloproteins: in situ scanning tunneling microscopy with submolecular resolution

In situ scanning tunneling microscopy (STM) of redox molecules, in aqueous solution, shows interesting analogies and differences compared with interfacial electrochemical electron transfer (ET) and ET in homogeneous solution. This is because the redox level represents a deep indentation in the tunnel barrier, with possible temporary electronic population. Particular perspectives are that both the bias voltage and the overvoltage relative to a reference electrode can be controlled, reflected in spectroscopic features when the potential variation brings the redox level to cross the Fermi levels of the substrate and tip. The blue copper protein azurin adsorbs on gold(111) via a surface disulfide group. Well resolved in situ STM images show arrays of molecules on the triangular gold(111) terraces. This points to the feasibility of in situ STM of redox metalloproteins directly in their natural aqueous medium. Each structure also shows a central brighter contrast in the constant current mode, indicative of 2- to 4-fold current enhancement compared with the peripheral parts. This supports the notion of tunneling via the redox level of the copper atom and of in situ STM as a new approach to long-range electron tunneling in metalloproteins.

Torsional modes in piezo helical springs

Piezo springs have been studied for their advantages in receiver applications at low frequencies. In this paper, piezo helical springs shaped from curved unimorphs are proposed for actuator designs in which the torsional modes are used to obtain electroelastic conversion. In comparison with the use of bimorphs as low frequency actuators, the helices show advantages of large strain capabilities and high compliance. These advantages are confirmed by numerical calculations.

Projections from dorsomedial part of the subnucleus oralis to the mesencephalic trigeminal neurons innervating the masseter muscle--a PHA-L and HRP double labeling study in the rat

When PHA-L was injected to dorsomedial part of the subnucleus oralis of the spinal trigeminal nucleus (Vodm), anterogradely labeled varicosities and boutons were observed in the mesencephalic trigeminal nucleus (Vme). The PHA-L labeling was seen mainly in the Vine ipsilateral to the injection side. If the injection sites were placed more medially containing both Vodm and parvocellular reticular nucleus (PCRt), more PHA-L labeling in contralateral Vme was observed. It appeared that the Vodm neurons projected predominantly to the ipsilateral Vme, while neurons in the PCRt adjacent to the Vodm projected bilaterally to the Vme. It was also seen that many PHA-L labeled varicosities and boutons surrounded or contacted on the Vme neurons counterstained with cresyl violet. These contacts were seen frequently in the ipsilateral Vme, occasionally in the contralateral nucleus. Some Vme neurons ipsilateral to the injection side were retrogradely labeled in a solidly-filled appearance following injection of PHA-L into the Vodm. When PHA-L was applied to the Vodm and HRP was injected to the masseter nerve on the same side, the relationship between PHA-L labeled terminals and HRP labeled Vme neurons was studied. The contacts between PHA-L labeled boutons and HRP labeled somata or processes of the Vme neurons were observed occasionally. PHA-L labeled terminals sometimes contacted on none-HRP-labeled somata counterstained with neutral red. Besides the PHA-L labeling in the Vme, the labeling was also seen in the medial parabrachial nucleus ipsilaterally, in the motor trigeminal nucleus bilaterally with ipsilateral predominance. In addition, an outstanding labeling band along the medial border of the principal sensory trigeminal nucleus (Vp) was observed following injection of PHA-L into the Vodm. The labeled terminals were concentrated in dorsomedial part of the Vp (Vpdm) and in juxtatrigeminal nucleus (JX), meanwhile many labeled fibres were distributed between the Vpdm and JX in the intertrigeminal region.

Ultrastructural analysis of inputs around the soma of an intra-cellularly labeled masseter muscle spindle afferent in cat mesencephalic trigeminal nucleus

Intra-axonal recording and labeling with HRP was performed to examine synaptic inputs around soma of mesencephalic trigeminal neuron (Vme) innervating the masseter muscle-spindles on electron microscopy. Intra-axonal injection of HRP was made in the mesencephalic tract. About twelve boutons contacting the labeled soma were observed from serial ultrathin sections. Among them eight boutons synapsed on the labeled soma, one bouton contacted on the soma but synapsed on an unlabeled dendrite nearby. Serially observing the other three boutons, no synaptic junctions were identified. The synapses between boutons and soma were mainly asymmetrical. Six boutons contained clear spherical vesicles (S-ending) and the other six contained spherical, oviod and flattened, namely pleomorphic clear vesicles (P-ending). Both S-endings and P-endings frequently contained large or small dense-core vesicles. Typical F-endings with predominantly flattened vesicles was not seen, though some P-endings contained more flattened vesicles. The significance of these observations was discussed.

Carbamazepine facilitates effects of GABA on rat hippocampus slices

AIM

To study the influence of carbamazepine (Car) on GABA effect in hippocampus.

METHODS

Evoked potentials were recorded on pyramidal cells in CA1 after stimulation (0.5 Hz, 50 microseconds) to Schaffer collaterals in rat hippocampal slices (350 microns).

RESULTS

Car 0.1 and 0.2 mmol.L-1 did not affect field potentials, whereas Car 0.2 mmol.L-1 plus GABA (0.1-1 mmol.L-1) gave rise to a stronger inhibition on field potentials than that of GABA alone. Bicuculline did not reverse Car facilitation on GABA inhibition on field potentials. (-)-Baclofen was more effective in inhibiting field potentials than GABA. Car 0.2 mmol.L-1 plus (-)-baclofen (1-5 mumol.L-1) brought an inhibition stronger than that of (-)-baclofen alone.

CONCLUSION

Car facilitates the effects of GABA on pyramidal cells in hippocampal CA1 region, probably related to GABAB receptors.

Cancer mortality in a Chinese population exposed to hexavalent chromium in water

This report is a clarification and further analysis of our previously published mortality study regarding groundwater contamination with hexavalent chromium (Cr+6) in the JinZhou area of China between 1965 and 1978. In our previous report, we stated that a significant excess of overall cancer mortality was observed (P = 0.04) in five Cr(+6)-contaminated villages combined. Further analysis revealed no clear statistical increase in cancer mortality in the three villages adjacent to the source of the contamination (P = 0.25), where 57% of the wells exceeded the European Community safe drinking water standard of 0.05 ppm Cr+6. These results do not indicate an association of cancer mortality with exposure to Cr(+6)-contaminated groundwater, but might reflect the influence of lifestyle or environmental factors not related to Cr+6. Further follow-up of this cohort is recommended.

Deformation-induced hierarchical flows and drag forces in bone canaliculi and matrix microporosity

Existing theories for interstitial flows in bone have only examined the contributions from different flow systems separately, such as the flows through the microporosity, the canaliculi, and the Haversian canals. An overall model encompassing the hierarchical microstructure is important to our understanding of the actual physics of flows in bone. The flow-induced drag forces and streaming electrical potentials could interact with the osteocytes to effect biological responses. A finite element model was developed to study the contributions from various hierarchical flow channels in bone. Cortical bone is modelled as a fully hydrated biphasic poroelastic material with a superposing network of one-dimensional channels radiating from the Haversian canals representing the canaliculi. Interfacial cross-flows between these one-dimensional channels and the neighbouring poroelastic matrix are driven by the pressure differences between the matrix and the channel. The model was subjected to stress fields simulating uniform compression and pure bending. The effects of the interfacial permeability and the solid content within the channels on the drag forces in the channels were assessed. Abrupt changes in these drag forces occurred as the channel solidity approached that of the microporosity. The results were quite sensitive to the interfacial permeability, i.e. the interconnectivity between the canalicular system and the matrix microporosity. This biomechanical model should be useful to the study of mechanotransduction in bone.

Comparative cutaneous testing with purified protein derivative and the antigen complex A60 in vaccinated subjects and tuberculosis patients

Some 840 bacille Calmette-Guérin (BCG)-vaccinated healthy controls and tuberculosis patients from two Chinese hospitals were submitted to comparative skin tests with purified protein derivative of tuberculin (PPD; as reference) and with the antigen complex A60 from Mycobacterium bovis BCG. In a first trial, including 581 persons (185 healthy juveniles, 180 healthy adults and 216 tuberculosis patients), a limited dose of A60 (1 microgram) was used. Performance of the A60 test was similar to that of 5 I.U. PPD for controls (cut-off values = 5 mm induration diameter), but lower than that seen for tuberculosis patients (10 mm cut-off values). A second survey was conducted on 259 persons (109 recently revaccinated healthy persons, considered as tuberculin-negative in the first trial, and 150 tuberculosis patients), using a higher dose of A60 (2 micrograms) and the same dose of PPD (5 I.U.). Similar results were obtained with the two tests in all cases, thus supporting the possibility of PPD replacement by A60 in cutaneous testing. The pattern of induration diameter distribution in healthy subjects who took part in the first testing round (64% positively rate) was displaced to the inactivity side (with a peak at 5 to 9-mm diameter), in comparison with the second round (90% positivity rate and peak at 10-14 mm). This indicates a progressive fading of cellular immunity reactions after BCG vaccination. In tuberculosis patients, no correlation was found among the following three parameters: positivity at cutaneous testing (with PPD or A60), titer of anti-A60 mycobacterial immunoglobulins in blood (IgG titer higher than cut-off line) and presence of mycobacteria in sputum.

Serological analysis of pulmonary and extrapulmonary tuberculosis with enzyme-linked immunosorbent assays for anti-A60 immunoglobulins

IgA, IgG, and IgM antibodies to mycobacterial antigen A60 were measured by ELISA in blood, pleural fluid, and cerebrospinal fluid from 560 patients with pulmonary and/or extrapulmonary tuberculosis who were being treated at hospitals in northern China and from 734 uninfected controls. Among 529 healthy persons (most of whom had been vaccinated with bacille Calmette-Guérin [BCG] and 287 of whom were tuberculin-positive), the rate of false-positive results was negligible; this observation ruled out interference of remote BCG vaccination with A60 assays at the chosen cutoff level. Rates of positivity for IgM and IgG, respectively, were 80% and 36% among patients with active primary pulmonary tuberculosis, 31% and 88.5% among patients with active postprimary pulmonary tuberculosis, 0 and 41% among patients with inactive pulmonary tuberculosis, and 30%-61% and 69%-86% among patients with extrapulmonary tuberculosis. Paired samples of blood and pleural fluid from patients with pleurisy contained IgA antibody to A60 at equal titers; in contrast, most patients with tuberculous meningitis (100% of whom had a positive ELISA result) had higher levels of IgG antibody to A60 in cerebrospinal fluid than in blood--proof of intrathecal synthesis.

[The clinical significance of detection of anti-BCG-A60 antibody by ELISA in diagnosis of tuberculosis]

In order to find out the clinical significance of detection of BCG-A60 antibody by ELISA in diagnosis of tuberculosis, 734 cases of non-tuberculosis patients and 560 cases of tuberculosis has been examined. The result of A60-ELISA test for IgG as diagnosilic criteria of tuberculosis, sensitivity is 84.5%, specificity is 89.3%, It shows satisfactory effect, so it can be used as an helpful method in clinical diagnosis of tuberculosis. IgG, IgA and IgM are measured at same time, and find that a combined use of the IgG and IgM ELISA studies considerably increases the significance of the test.

Mesencephalic trigeminal nucleus neurons with collaterals to both the masseter and the inferior alveolar nerves. A fluorescent double-labeling study in the rat

After fluorescent tracers were applied to the inferior alveolar nerve and the masseter nerve on the same side of the rat, double-labeled neurons were observed in the caudal part of the mesencephalic trigeminal nucleus (Vme), reflecting simultaneous innervation of both the periodontal ligaments and masseter muscle spindles by collaterals of peripheral processes of single Vme neurons.

Three-dimensional structure of human basic fibroblast growth factor, a structural homolog of interleukin 1 beta

The three-dimensional structure of the 146-residue form of human basic fibroblast growth factor (bFGF), expressed as a recombinant protein in yeast, has been determined by x-ray crystallography to a resolution of 1.8 A. bFGF is composed entirely of beta-sheet structure, comprising a three-fold repeat of a four-stranded antiparallel beta-meander. The topology of bFGF is identical to that of interleukin 1 beta, showing that although the two proteins share only 10% sequence identity, bFGF, interleukin 1, and their homologs comprise a family of structurally related mitogenic factors. Analysis of the three-dimensional structure in light of functional studies of bFGF suggests that the receptor binding site and the positively charged heparin binding site correspond to adjacent but separate loci on the beta-barrel.

An investigation of aetiology and heredity of pterygium. Report of 11 cases in a family

A family with pterygium affecting 11 members of 3 generations was reported. Although the disease is not necessarily hereditary in most of the patients, the mode of transmission in this particular family was autosomal dominant. The relationship between individual predisposition and the external factors in pterygium formation is briefly discussed.