[Influencing factors of iron metabolism assessment in patients with myelodysplastic syndrome: A retrospective study]

Objective: To analyze the influencing factors of iron metabolism assessment in patients with myelodysplastic syndrome. Methods: MRI and/or DECT were used to detect liver and cardiac iron content in 181 patients with MDS, among whom, 41 received regular iron chelation therapy during two examinations. The adjusted ferritin (ASF) , erythropoietin (EPO) , cardiac function, liver transaminase, hepatitis antibody, and peripheral blood T cell polarization were detected and the results of myelofibrosis, splenomegaly, and cyclosporine were collected and comparative analyzed in patients. Results: We observed a positive correlation between liver iron concentration and ASF both in the MRI group and DECT groups (r=0.512 and 0.606, respectively, P<0.001) , only a weak correlation between the heart iron concentration and ASF in the MRI group (r=0.303, P<0.001) , and no significant correlation between cardiac iron concentration and ASF in the DECT group (r=0.231, P=0.053) . Moreover, transfusion dependence in liver and cardiac [MRI group was significantly associated with the concentration of iron in: LIC: (28.370±10.706) mg/g vs (7.593±3.508) mg/g, t=24.30, P<0.001; MIC: 1.81 vs 0.95, z=2.625, P<0.05; DECT group: liver VIC: (4.269±1.258) g/L vs (1.078±0.383) g/L, t=23.14, P<0.001: cardiac VIC: 1.69 vs 0.68, z=3.142, P<0.05]. The concentration of EPO in the severe iron overload group was significantly higher than that in the mild to moderate iron overload group and normal group (P<0.001) . Compared to the low-risk MDS group, the liver iron concentration in patients with MDS with cyclic sideroblasts (MDS-RS) was significantly elevated [DECT group: 3.80 (1.97, 5.51) g/L vs 1.66 (0.67, 2.94) g/L, P=0.004; MRI group: 13.7 (8.1,29.1) mg/g vs 11.6 (7.1,21.1) mg/g, P=0.032]. Factors including age, bone marrow fibrosis, splenomegaly, T cell polarization, use of cyclosporine A, liver aminotransferase, and hepatitis antibody positive had no obvious effect on iron metabolism. Conclusion: There was a positive correlation between liver iron concentration and ASF in patients with MDS, whereas there was no significant correlation between cardiac iron concentration and ASF. Iron metabolism was affected by transfusion dependence, EPO concentration, and RS.

Lymphocyte count predicts the severity of COVID-19: Evidence from a meta-analysis

BACKGROUND

In December 2019, coronavirus disease 2019 (COVID-19) was reported firstly in Wuhan, China. COVID-19 is currently a global pandemic.

AIM

To assess the suitability of lymphocyte count as a biomarker of COVID-19 severity.

METHODS

Five literature databases (PubMed/MEDLINE, Web of Science, Google Scholar, Embase, and Scopus) were searched to identify eligible articles. A meta-analysis was performed to calculate the standard mean difference (SMD) and 95% confidence interval (CI) of lymphocyte counts in coronaviral pneumonia cases.

RESULTS

Eight studies, including 1057 patients, were integrated in the meta-analysis. Lymphocyte counts were associated with severe coronavirus (CoV) infection (SMD = 1.35, 95%CI: 1.97 to 0.37, P < 0.001, I² = 92.6%). In the subgroup analysis stratified by prognosis, lymphocytes were associated with CoV infection mortality (n = 2, SMD = 0.42, 95%CI: 0.66 to 0.19, P < 0.001, I² = 0.0%), severity (n = 2, SMD = 0.93, 95%CI: 1.20 to 0.67, P < 0.001, I² = 0.0%), and diagnostic rate (n = 4, SMD = 2.32, 95%CI: 3.60 to 1.04, P < 0.001, I² = 91.2%).

CONCLUSION

Lymphocyte count may represent a simple, rapid, and commonly available laboratory index with which to diagnosis infection and predict the severity of CoV infections, including COVID-19.

Maxillary molar root and canal morphology of Neolithic and modern Chinese

OBJECTIVE

This study aimed to characterize Neolithic human maxillary molars from archeological remains at the Jiaojia site, Shandong, China, and compare their ultrastructural features with sex and age-matched modern locals.

DESIGN

Maxillary first (n = 86) and second (n = 80) molars in 5000-year-old individuals (n = 50) from the Jiaojia site were scanned by cone-beam computed tomography (CBCT). Sex and age-matched control groups were assigned from oral surgical patients at Shandong University. Images were analyzed for crown size, root length, root morphology, canal inter-orifice distances, mesiobuccal canal morphology, and second mesiobuccal (MB2) canal prevalence and location. Neolithic and modern values were compared statistically using Chi-squared and Mann-Whitney test at p < .05.

RESULTS

Crown and root size were smaller, and canal inter-orifice distances were shorter in Neolithic maxillary molars than their modern counterparts. For mesiobuccal roots, Weine's Type I single canals were the most prevalent in Neolithic and modern first and second molars. MB2 canal prevalence were not significantly different (p > .05) in Neolithic (53.3%) or modern (60.5%) first molars, and Neolithic (11.3%) or modern (21.3%) second molars. But, MB2 prevalence was significantly higher for modern than ancient male first (p = .032) and second (p = .005) molars. Additionally, MB2 were located more mesially and closer to MB1 in Neolithic than modern molars.

CONCLUSIONS

Maxillary molar root and canal morphology of ancient 5000-year-old remains at the Jiaojia site resemble that of local patients. A trend towards larger tooth size, and more dispersed MB2 canals over this short evolutionary period warrants additional investigation.

[COVID-19 epidemic and its characteristics in Heilongjiang province]

Objective: To describe the COVID-19 epidemic and its characteristics in Heilongjiang province, and provide evidence for the further prevention and control of COVID-19 in the province. Methods: The information of COVID-19 cases and clusters were collected from national notifiable disease report system and management information system for reporting public health emergencies of China CDC. The Software's of Excel 2010 and SPSS 23.0 were applied for data cleaning and statistical analysis on the population, time and area distributions of COVID-19 cases. Results: On January 22, 2020, the first confirmed case of COVID-19 was reported in Heilongjiang. By March 11, 2020, a total of 482 cases domestic case of COVID-19, The incidence rate was 1.28/100 000, the mortality rate was 2.70% (13/482) in 13 municipalities in Heilongjiang. There were 81 clusters of COVID-19, The number of confirmed cases accounted for 79.25% (382/482) of the total confirmed cases and 12 cases of deaths. The family clusters accounted for 86.42% (70/81). Compared with the sporadic cases, the mortality rate, proportion of elderly cases aged 60 or above and severe or critical cases of clinical classification were all higher in the clusters especially the family clusters, but the differences were not significant (P>0.05). There were 34 clusters involving more than 5 confirmed cases accounted for 41.98% (34/81) of the total clusters, the involved cases accounted for 68.31% (261/382) of the total cases of clusters. There were significant differences in age distribution of the cases among the case clusters with different case numbers. In the clusters involving 6-9 cases, the proportion of cases aged 65 years or above was more (26.53%, 39/147). Conclusions: The incidence rate of COVID-19 was relatively high and the early epidemic was serious in Heilongjiang, The number of cases was large in clusters especially family clusters.

Exploring plasma metabolomic changes in sepsis: a clinical matching study based on gas chromatography-mass spectrometry

Background

Sepsis is a deleterious systemic inflammatory response to infection, and despite advances in treatment, the mortality rate remains high. We hypothesized that plasma metabolism could clarify sepsis in patients complicated by organ dysfunction.

Methods

Plasma samples from 31 patients with sepsis and 23 healthy individuals of comparable age, gender, and body mass index (BMI) were collected. Plasma metabolites were detected through gas chromatography–mass spectrometry (GC–MS), and relevant metabolic pathways were predicted using the Kyoto Encyclopedia of Genes and Genomics (KEGG) pathway database. Student’s t-test was employed for statistical analysis. In addition, to explore sepsis organ dysfunction, plasma samples of sepsis patients were further analyzed by metabolomics subgroup analysis according to organ dysfunction.

Results

A total of 222 metabolites were detected, which included 124 metabolites with statistical significance between the sepsis and control groups. Among these, we found 26 were fatty acids, including 3 branched fatty acids, 10 were saturated fatty acids, and 13 were unsaturated fatty acids that were found in sepsis plasma samples but not in the controls. In addition, 158 metabolic pathways were predicted, 74 of which were significant. Further subgroup analysis identified seven metabolites in acute kidney injury (AKI), three metabolites in acute respiratory distress syndrome (ARDS), seven metabolites in sepsis-induced myocardial dysfunction (SIMD), and four metabolites in acute hepatic ischemia (AHI) that were significantly different. The results showed that the sepsis samples exhibited extensive changes in amino acids, fatty acids, and tricarboxylic acid (TCA)–cycle products. In addition, three metabolic pathways—namely, energy metabolism, amino acid metabolism, and lipid metabolism—were downregulated in sepsis patients.

Conclusions

The downregulated energy, amino acid, and lipid metabolism found in our study may serve as a novel clinical marker for the dysregulated internal environment, particularly involving energy metabolism, which results in sepsis.

Influence of body mass index on the clinicopathological features of 13,995 papillary thyroid tumors

PURPOSE

This retrospective study aimed to assess the association between obesity, gender, and specific clinicopathological features in patients with papillary thyroid cancer (PTC) and whether diagnostic ultrasonography (US) is adversely affected by obesity in these patients.

MATERIALS AND METHODS

This study retrospectively analyzed 13,995 adult patients with PTC from a single medical center in China. Data stratification was performed to assess the association of obesity with US features and aggressive clinicopathological features in different models according to the World Health Organization Body Mass Index (WHO-BMI) and Chinese BMI classification (CN-BMI). The odds ratio (OR) of malignant US features and aggressive clinicopathological features was calculated from binary logistic regression models.

RESULTS

The BMI, obesity ratio, malignant US features, and aggressive pathological characteristics of males were significantly higher than those of females. After adjusting for confounding factors, the association of obesity with malignant US features and aggressive pathological characteristics was found to be sex-dependent. Next, obesity (WHO-BMI) was found to have an "interfering effect" on the US assessment of PTC (OR = 0.754, 95% CI 0.609-0.932, P = 0.009) in women. Among both sexes, obesity (WHO-BMI) increased the risk of tumor size (OR_male = 1.539 and OR_female = 1.521) and multifocality (OR_male = 1.659 and OR_female = 1.449). However, obesity did not increase the risk of capsular invasion or tumor staging in males. The above results are consistent with the CN-BMI. In addition, age was found to have an "interfering effect" on the US evaluation of malignant nodules in both sexes.

CONCLUSION

The results of our study confirm that higher BMI is significantly associated with aggressive clinicopathological features of PTC. Gender differences were present with obesity ratios and aggressive clinicopathological features being significantly higher in men.

Downregulation of nuclear protein-1 induces cell cycle arrest in G0/G1 phase in glioma cells in vivo and in vitro via P27

Nuclear protein-1 (NUPR1), also named as p8 or Com1, has been since found overexpressed in several human malignant tumor cells, such as glioma. NUPR1 also regulates cell cycle progression, however, the role of NUPR1 in regulating glioma cell cycle remains poorly understood. Knockdown efficiency of U87 and U251 cells infected with the lentiviral vector was detected by quantitative real-time PCR and western blot in vitro and in vivo. Flow cytometry and western blot were used to explore a mechanism by which NUPR1 modulates cell cycle in U87 and U251 cells. Immunohistochemistry was applied to detect expression levels of P27, CDK2, and cyclin E in human glioma tissues with NUPR1 positive expression and tumorigenesis in nude mice. We confirmed that the downregulation of NUPR1 arrested the cell cycle in the G0/G1 phase in U87 and U251 cells in vitro. Furthermore, the expression level of P27 was increased, and CDK2 and cyclin E were decreased upon silencing NUPR1 expression in vitro and in vivo. In conclusion, the knockdown of NUPR1 induces cell cycle arrest in the G0/G1 phase in glioma cells via P27.

[Predict response to decitabine in patients with myelodysplastic syndrome and related neoplasms]

目的

探索预测骨髓增生异常综合征（MDS）及相关肿瘤地西他滨治疗反应的临床及分子学指标。

方法

回顾性分析109例接受地西他滨治疗的MDS及相关肿瘤患者临床资料，采用二代测序检测MDS常见突变基因的突变情况，分析患者临床特征及基因突变与地西他滨临床反应的关系。

结果

地西他滨中位疗程数为4（2~11）个，共74例（67.9%）患者获得治疗反应，其中30例（27.5%）获得完全缓解（CR）；35例（32.1%）患者无反应。单因素分析结果显示，国际预后积分系统（IPSS）中危2+高危、复杂核型、单体核型、7号染色体异常及1个疗程后PLT倍增的患者可获得更高的CR率。66.7%（14/21）的复杂核型患者、58.8%（10/17）的单体核型患者及66.7%（10/15）的TP53基因突变患者获得CR；TP53基因突变常合并复杂核型及单体核型；多因素分析显示TP53突变、1个疗程后PLT倍增及复杂核型是预测地西他滨治疗获得CR的独立预后因素，其中TP53突变是最强的预测因子（OR=4.39，95%CI 1.20~16.06，P=0.026）。

结论

TP53基因突变、1个疗程后PLT倍增及复杂核型可预测地西他滨完全缓解。

[Interaction between family history of diabetes and hyperlipidemia on risk of diabetes in population with normotension in Harbin: a cross-sectional study]

Objective: To explore the interaction between family history of diabetes and hyperlipidemia on the risk of diabetes in population with normotension. Methods: A multistage stratified probability random sampling was conducted to select a representative sample of urban residents aged 20-74 years in Harbin. A total of 376 diabetes patients with normotension and 3 692 residents with normal blood pressure, normal fasting glucose, and normal 2 hours glucose from OGTT were surveyed. The interaction was evaluated by using crossover analysis and additive model. Results: Multivariate logistic regression analysis indicated that there was a possible additive interaction between family history of diabetes and hyperlipidemia on the risk of diabetes. The relative excess risk due to the interaction, the attributable proportion due to the interaction, and the synergy index were 1.97 (95%CI:-0.32-4.26), 0.30 (95%CI: 0.03-0.57), and 1.54 (95%CI: 0.96-2.47), respectively. There were significant combination effects between family history of diabetes and high both total cholesterol and triglyceride, isolated high total cholesterol, and isolated high triglyceride levels; the ORs were 10.55 (95%CI: 5.62-19.80), 7.81 (95%CI: 3.65-16.71) and 5.13 (95%CI: 3.22-8.16), respectively. Conclusion: There might be synergistic effect between family history of diabetes and hyperlipidemia on the risk of diabetes in population with normotension.

[Clinical analysis of 34 cases with sepsis and systemic capillary leak syndrome]

Objective: To study the clinical characteristics of sepsis with systemic capillary leak syndrome(SCLS) and to evaluate the therapeutic effect and clinical significance of fluid therapy adjusted timely in these patients. Methods: The clinical data of 34 patients with sepsis and SCLS in the Department of Hepatobiliary Surgery ICU of General Hospital of People's Liberation Army General Hospital from July 2014 to January 2016 were retrospectively analyzed.There were 21 males and 13 females, aged from 21 to 74 years, with an average age of 56.3 years.Primary disease as follows: 18 cases with severe acute pancreatitis, 7 postoperative cases of subtotal hepatectomy, 5 postoperative cases of pancreatoduodenectomy, 4 postoperative cases of cholelithiasis.These patients were divided into survival group and death group according to their 28-day survival status.The clinical data including C-reactive protein(CRP), platelets (PLT), brain natriuretic peptide (BNP), the level of arterial blood lactic acid(LAC), oxygenation index(PaO₂/FiO₂, OI), net fluid balance(NFB) and norepinephrine dosage(NE) were collected and compared between two groups at three different intervals(day 1-3, day 4-6, day 7-9). The measurement data and numeration data were statistically analyzed with t test and χ² test respectively to explore the inherent characteristics of the disease evolution and its clinical significance. Results: The survival group (n=23)and the death group(n=11)had no significant difference in the characteristics of basic clinical characters.The condition of the survival group and the death group were both in progress in 1-3 days period manifested as increased CRP(t=-0.473, P=0.640) and BNP levels(t=0.140, P=0.895), decreased PLT counts(t=-0.505, P=0.620) in the inflammatory response, decreased LAC(t=-1.008, P=0.320) and OI level (t=-2.379, P=0.020)in tissue perfusion index, and positive fluid balance(NFB: t=0.910, P=0.370), required NE(t=-0.853, P=0.400) to maintain effective perfusion pressure with systemic edema in both groups.There was no significant difference of all these clinical parameters between the two groups.The patients' condition of the survival group reached a plateau phase, whereas all relative indicators of the death group implied significant aggravation and deterioration of systemic infection(CRP: t=-3.438, P=0.000; PLT: t=1.649, P=0.110; BNP: t=-10.612, P=0.000), tissue perfusion (LAC: t=-11.305, P=0.000; OI: t=2.743, P=0.010)and tissue edema NFB(t=-4.257, P=0.000) and NE(t=-7.956, P=0.000) in 4-6 days period.In the last 7-9 days period the patients' condition of the survival group took a turn for improvement, yet the condition of the death group continued to deteriorate, refractory septic shock developed and multiple organ dysfunction syndrome followed afterwards inevitably(CRP: t=-10.036, P=0.000; PLT: t=6.061, P=0.000; BNP: t=-10.119, P=0.000; LAC: t=-24.466, P=0.000; OI: t=13.443, P=0.010; NFB: t=-8.345, P=0.000; NE: t=-7.121, P=0.000). Conclusions: The condition of patient with sepsis and SCLS would be improved markedly at the critical turning point around 7-9 days period since the effective systemic treatment began.If the infection does not be significantly constrolled and SCLS still remains in a sustained extravasation period in 7-9 days, the prognosis of these patients may be worse and the mortality may be higher than that of the patients mentioned before.

[Understanding the risk factors for infectious diseases, their prevention, and control, among residents of Zhejiang Province]

Objective: To investigate the understanding of infectious diseases, their prevention, and control, and the factors influencing this literacy among urban and rural residents of Zhejiang Province. Methods: In November- December 2014, a multistage stratified cluster sampling questionnaire was administered at study sites in eight districts of Zhejiang province: Hangzhou city Gongshu district, Hangzhou city Chun'an county, Wenzhou city Cangnan county, Dongyang city, Jiaxing city Jiashan county, Zhoushan city Putuo district, Linhai city, Lishui city Jinyun county. The inclusion criteria were: 15-60 years old, living locally for more than six continuous months, and no mental illness. The exclusion criteria were: foreigner residing locally, resident of Hong Kong, Macau, or Taiwan, or unable to communicate through speech or writing. In this study, 4 091 questionnaires were distributed, and 4 020 valid questionnaires were returned(98.26%). Health literacy regarding infectious diseases was measured at five levels: knowledge, skills, behaviors, access to information, and understanding of the prevention of infectious diseases. A total score was calculated for each questionnaire, and a total score of ≥80 was deemed to indicate an understanding of the prevention of infectious diseases. A χ² test was used to compare the levels of health literacy in different populations with single-factor analyses, and a multivariate unconditional logistic regression model was used to analyze the factors affecting infectious diseases prevention and treatment literacy levels. Results: Of the 4 020 respondents(aged(43.84 ± 10.28)years), 1 964 were male(48.86%)and 2 056 were female(51.14%). In the total surveyed population, 15.17%(n=610)understood the prevention of infectious diseases, 294 were male(14.97%)and 316 were female(15.37%)(χ²=2.48, P=0.115). When the participants in the different age groups were analyzed, 23.11%, 20.29%, 13.27%, and 11.04% of those aged 18- 29(n=116), 30- 39(n= 166), 40- 49(n=178), and ≥50 years(n=150), respectively, understood infectious disease prevention(χ²= 63.16, P<0.001). When the participants were analyzed according to education, 46.01%, 24.86%, 12.03%, 5.27%, or 2.39% of those educated at university(n=167), at high school/vocational school/college(n=175), at middle school(n=215), at elementary school(n=46), or who were illiterate/slightly literate(n=7), respectively, understood infectious disease prevention(χ²=436.67, P<0.001). Among the urban(n=336)and rural participants(n=274), 18.98% and 12.18% understood infectious disease prevention, respectively(χ²= 35.57, P<0.001), so the urban residents had better health literacy than rural residents(OR=1.28, 95% CI= 1.06- 1.54), and those aged 18- 29 or 30- 39 years had even better health literacy than the rural residents(OR=1.39, 95%CI=1.01-1.91). When the health literacy levels of migrant workers were compared with those of agency/institutional personnel, business people, unemployed, and retirees, the OR(95% CI)values were 2.52(1.82-3.49), 1.69(1.24-2.30), 2.99(1.65-5.39), and 2.43(1.59-3.72), respectively. When the illiterate/slightly literate were compared with those educated at university, high school/vocational school/secondary school, and junior high school, the OR(95%CI)values were 35.11(15.73-78.36), 13.31(6.11-28.99), and 5.37(2.48-11.62), respectively. Conclusion: Limited levels of health literacy are common among the residents of Zhejiang Province. Lower education level, older age, and rural residence were predictors of low health literacy in this study.

Rehmannia glutinosa oligosaccharide induces differentiation of bone marrow mesenchymal stem cells into cardiomyocyte-like cells

The aim of this study was to observe the effect of Rehmannia glutinosa oligosaccharide (RGO) on differentiation of bone marrow mesenchymal stem cells (MSCs) into cardiomyocyte-like cells . Rat MSCs were isolated, treated, and grouped as follows: RGO treatment group, 5-azacytidine (5-aza) treatment group, RGO + 5-aza treatment group, and control group. Following a four-week induction period, cardiac troponin I (cTnI) levels in MSCs were quantified by chemiluminescence, and the levels of myocardial enzymes creatine kinase (CK) and creatine kinase isoenzyme-MB (CK-MB) were measured using a dry chemistry analyzer. The cTnI- and connexin 43 (Cx43)-positive MSC population was identified by immunofluorescence, and expression levels of cTnI and Cx43 were analyzed by western blots. Following induction, cTnI, CK, and CK-MB levels were significantly higher in the RGO + 5-aza group as compared with the RGO and 5-aza groups (P < 0.05). In addition, fluorescence intensity of cTnI and Cx43 was higher in the RGO + 5-aza group as compared with the RGO and 5-aza groups. No cTnI- or Cx43-positive cells were detected in the control group. Western blot analysis further confirmed that cTnI and Cx43 were not expressed in the control group, while cTnI and Cx43 was higher in the RGO + 5-aza group than in the RGO and 5-aza groups. These results suggest that MSCs can be induced by RGO to differentiate into cardiomyocyte-like cells in vitro, and that RGO in combination with 5-aza enhance differentiation of MSCs.

Aquaporin 4 inhibition decreased synthesis of cytokines by acetazolamide in the hippocampus of rats with pentrazol-induced chronic epilepsy

Epilepsy refers to a clinical syndrome generated by spontaneous seizures in the central nervous system. Epilepsy triggers a complex pathological process including inflammatory response and aquaporin 4 (AQP4) increase. It has been reported that AQP4 helps to enhance the immunological function of the central nervous system in pathological conditions, but the relationship between AQP4 and inflammatory cytokines is poorly understood in chronic epilepsy processes. As an inhibitor of sulfonamide carbonic anhydrase (CA), acetazolamide (AZA) may inhibit water infiltration through AQP4. In this context, pentylenetetrazole (PTZ) is used to induce the chronic epilepsy model in rats to study the chronic epilepsy effects of AQP4 inhibition on proinflammatory cytokine expression in the hippocampus and proinflammatory cytokine quantification analysis of the plasma. Based on the assumption that AQP4 regulates proinflammatory cytokine expression, this article aims to demonstrate this effect in chronic epilepsy of rats. Rats were divided into four groups and were treated with different drugs: saline (Control), acetazolamide (AZA), pentylenetetrazole (PTZ), and pentylenetetrazole plus acetazolamide (PTZ+AZA). The data showed that seizures increased proinflammatory cytokine expression and that AZA significantly inhibited AQP4 expression. Overall, the results suggested that AQP4 inhibition could weaken excitotoxicity in epileptogenesis by reducing proinflammatory cytokines in the hippocampus. The findings provide a new insight into the involvement of cerebral edema insult and proinflammatory cytokines in the process of chronic epilepsy.

Glabridin nanosuspension for enhanced skin penetration: formulation optimization, in vitro and in vivo evaluation

Glabridin, a polyphenolic flavonoid from licorice, has inspired great interest for its antioxidant, anti-inflammatory and skin-lightening activities. However, low water solubility and poor stability of glabridin impedes its topical application in cosmetic products and therapies of dermal diseases. The purpose of this study was to develop a nanosuspension formulation of glabridin to improve its skin permeation. Glabridin nanosuspensions were prepared using anti-solvent precipitation-homogenization method, and Box-Behnken design was adopted to investigate the effects of crucial formulation variables on particle size and to optimize the nanosuspension formulation. The optimal formulation consisted of 0.25% glabridin, 0.47% Poloxamer 188 and 0.11% Polyvinylpyrrolidone K30, and the obtained nanosuspension showed an average particle size of 149.2 nm with a polydispersity index of 0.254. Furthermore, the nanosuspension exhibited significantly enhanced drug permeation flux of glabridin through rat skin with no lag phase both in vitro and in vivo, compared to the coarse suspension and physical mixture. The glabridin nanosuspension showed no significant particle aggregates and a drug loss of 5.46% after storage for 3 months at room temperature. With its enhanced skin penetration, the nanosuspension might be a more preferable formulation for topical administration of poorly soluble glabridin.

Superconductivity in topological insulator Sb2Te3 induced by pressure

Topological superconductivity is one of most fascinating properties of topological quantum matters that was theoretically proposed and can support Majorana Fermions at the edge state. Superconductivity was previously realized in a Cu-intercalated Bi₂Se₃ topological compound or a Bi₂Te₃ topological compound at high pressure. Here we report the discovery of superconductivity in the topological compound Sb₂Te₃ when pressure was applied. The crystal structure analysis results reveal that superconductivity at a low-pressure range occurs at the ambient phase. The Hall coefficient measurements indicate the change of p-type carriers at a low-pressure range within the ambient phase, into n-type at higher pressures, showing intimate relation to superconducting transition temperature. The first principle calculations based on experimental measurements of the crystal lattice show that Sb₂Te₃ retains its Dirac surface states within the low-pressure ambient phase where superconductivity was observed, which indicates a strong relationship between superconductivity and topology nature.

Semi-automatic laboratory goniospectrometer system for performing multi-angular reflectance and polarization measurements for natural surfaces

In this paper, the design and operation of the Northeast Normal University Laboratory Goniospectrometer System for performing multi-angular reflected and polarized measurements under controlled illumination conditions is described. A semi-automatic arm, which is carried on a rotated circular ring, enables the acquisition of a large number of measurements of surface Bidirectional Reflectance Factor (BRF) over the full hemisphere. In addition, a set of polarizing optics enables the linear polarization over the spectrum from 350 nm to 2300 nm. Because of the stable measurement condition in the laboratory, the BRF and linear polarization has an average uncertainty of 1% and less than 5% depending on the sample property, respectively. The polarimetric accuracy of the instrument is below 0.01 in the form of the absolute value of degree of linear polarization, which is established by measuring a Spectralon plane. This paper also presents the reflectance and polarization of snow, soil, sand, and ice measured during 2010-2013 in order to illustrate its stability and accuracy. These measurement results are useful to understand the scattering property of natural surfaces on Earth.

Superconductivity of the topological insulator Bi2Se3 at high pressure

The pressure-induced superconductivity and structural evolution of Bi2Se3 single crystals are studied. The emergence of superconductivity at an onset transition temperature (Tc) of about 4.4 K is observed at around 12 GPa. Tc increases rapidly to a maximum of 8.2 K at 17.2 GPa, decreases to around 6.5 K at 23 GPa, and then remains almost constant with further increases in pressure. Variations in Tc with respect to pressure are closely related to the carrier density, which increases by over two orders of magnitude from 2 to 23 GPa. High-pressure synchrotron radiation measurements reveal structural transitions at around 12, 20, and above 29 GPa. A phase diagram of superconductivity versus pressure is also constructed.

Seroprevalence of hepatitis C, hepatitis B virus and syphilis in HIV-1 infected patients in Shandong, China

To determine the seroprevalence of hepatitis C virus (HCV), hepatitis B virus (HBV) and syphilis in HIV-1-infected patients and related risk factors in Shandong province, China, we tested all eligible participants between 2000 and 2010 for the presence of anti-HCV antibody, hepatitis B surface antigen (HBsAg) and non-treponemal antibodies for syphilis after informed consent. Among 2087 HIV-infected patients, anti-HCV antibody was present in 41.2%, HBsAg in 12.6% and rapid plasma reagin (RPR) reactivity in 19.6%. In the multivariate logistic regression model, male gender (adjusted odds ratio [aOR] = 1.41), minority ethnicity (aOR = 1.72), syphilis infection (aOR = 1.40), former paid blood donors (aOR = 3.36), blood transfusion recipients (aOR = 2.91) and injection drug users (aOR = 1.98) were significantly associated with HCV infection. HCV infection (aOR = 1.40) and being men who have sex with men (aOR = 2.38) were significantly associated with syphilis infection. Co-infection with HCV, HBV and syphilis was observed frequently in all described subgroups of HIV infection. The results of this study suggest that it is necessary to screen for these viruses and syphilis in all Chinese HIV-infected patients.

Stability and strength of transition-metal tetraborides and triborides

Using density functional theory, we show that the long-believed transition-metal tetraborides (TB(4)) of tungsten and molybdenum are in fact triborides (TB(3)). This finding is supported by thermodynamic, mechanical, and phonon instabilities of TB(4), and it challenges the previously proposed origin of superhardness of these compounds and the predictability of the generally used hardness model. Theoretical calculations for the newly identified stable TB(3) structure correctly reproduce their structural and mechanical properties, as well as the experimental x-ray diffraction pattern. However, the relatively low shear moduli and strengths suggest that TB(3) cannot be intrinsically stronger than c-BN. The origin of the lattice instability of TB(3) under large shear strain that occurs at the atomic level during plastic deformation can be attributed to valence charge depletion between boron and metal atoms, which enables easy sliding of boron layers between the metal ones.

[The changes of density of platelet glycoprotein (GP) II b/III a receptor in the perioperative period of gastrectomy in aged rats]

AIM

To investigate changes of density of platelet glycoprotein (GP) II b/III a receptor in the perioperative period of gastrectomy in aged rats.

METHODS

The subtotal gastrectomy operation was performed in 16 adult rats and 16 aged rats respectively. Platelet surface density of GP II b/III receptors were determined by flow cytometric analysis before and 6, 12, 24, 48, 72 hours after operation.

RESULTS

6, 12, 24, 48 and 72 hours after operation, the density of GP II b/III a in aged group increased continuously compared with preoperative period (6h, 12, 72: P < 0.05; 24, 48: P < 0.01).

CONCLUSION

Gastrectomy can lead to an increase of density of platelet GP II b/III a receptor in aged rats.

Human immunodeficiency virus type 1 (HIV-1) protein Vif inhibits the activity of HIV-1 protease in bacteria and in vitro

Human immunodeficiency virus type 1 (HIV-1) Vif is required for productive infection of T lymphocytes and macrophages. Virions produced in the absence of Vif have abnormal core morphology and those produced in primary T cells carry immature core proteins and low levels of mature capsid (M. Simm, M. Shahabuddin, W. Chao, J. S. Allan, and D. J. Volsky, J. Virol. 69:4582-4586, 1995). To investigate whether Vif influences the activity of HIV-1 protease (PR), the viral enzyme which is responsible for processing Gag and Gag-Pol precursor polyproteins into mature virion components, we transformed bacteria to inducibly express truncated Gag-Pol fusion proteins and Vif. We examined the cleavage of polyproteins consisting of matrix to PR (Gag-PR), capsid to PR (CA-PR), and p6Pol to PR (p6Pol-PR) and evaluated HIV-1 protein processing at specific sites by Western blotting using antibodies against matrix, capsid, and PR proteins. We found that Vif modulates HIV-1 PR activity in bacteria mainly by preventing the release of mature MA and CA from Gag-PR, CA from CA-PR, and p6Pol from p6Pol-PR, with other cleavages being less affected. Using subconstructs of Vif, we mapped this activity to the N-terminal half of the molecule, thus identifying a new functional domain of Vif. Kinetic study of p6Pol-PR autocatalysis in the presence or absence of Vif revealed that Vif and N'Vif reduce the rate of PR-mediated proteolysis of this substrate. In an assay of in vitro proteolysis of a synthetic peptide substrate by purified recombinant PR we found that recombinant Vif and the N-terminal half of the molecule specifically inhibit PR activity at a molar ratio of the N-terminal half of Vif to PR of about 1. These results suggest a mechanism and site of action of Vif in HIV-1 replication and demonstrate novel regulation of a lentivirus PR by an autologous viral protein acting in trans.

Immunoglobulin E and circulating immune complexes in endolymphatic hydrops

Levels of circulating immune complexes (CICs) in 59 patients with Meniere's disease and total serum immunoglobulin E (IgE) levels in a subgroup of 42 of the 59 were determined quantitatively for possible abnormalities of humoral immunity. Significant differences in average IgE levels between the 42 patients with Meniere's disease and 18 normal control subjects were not determined; however, five (11.9%) of the 42 patients were found to have obviously raised IgE levels. Elevated CIC levels were found in 19 (32.2%) of the 59 patients with Meniere's disease and in one (2.3%) of the 43 control subjects. This difference was statistically significant. The possible mechanisms of immune-mediated endolymphatic hydrops are discussed.