Transcriptomic analysis reveals the regulatory mechanism underlying the indirubin-mediated amelioration of dextran sulfate sodium-induced colitis in mice

CONTEXT

Aryl hydrocarbon receptor (AhR) agonists are potential therapeutic agents for ulcerative colitis (UC). Indirubin (IDR), which is a natural AhR ligand approved for leukemia treatment, ameliorates dextran sulfate sodium (DSS)-induced colitis in mice. However, the therapeutic mechanisms of IDR are unknown, limiting its application.

OBJECTIVE

This study explores the therapeutic mechanisms of IDR in DSS-induced colitis using transcriptomic analysis.

MATERIALS AND METHODS

Male BALB/c mice were categorized to six groups: normal, DSS model (2% DSS), IDR treatment (10, 20 and 40 mg/kg), and sulfasalazine (520 mg/kg) groups. The drugs were intragastrically administered for 7 consecutive days. The disease activity index (DAI) was recorded. After euthanasia, the colon length was measured, and histopathological examination, immunohistochemistry staining using F4/80, and colonic transcriptomic analysis were conducted. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting (WB) were conducted to verify our findings.

RESULTS

Compared with DSS, IDR treatment decreased the DAI score by 64.9% and increased colon length by 26.2%. Moreover, it alleviated mucosal injury and reduced macrophage infiltration. Transcriptomic analysis identified several downregulated genes (Igkvs and Nlrp3), as well as Nlrp3/Il1β and hemoglobin gene networks, after IDR treatment. The abundances of NF-κB p65, NLRP3, IL-1β, and HBA decreased by 69.1, 59.4, 81.1, and 83.0% respectively, after IDR treatment.

DISCUSSION AND CONCLUSION

Apart from the well-documented NF-κB signalling pathway, IL-17A, and NLRP3-IL-1β, the suppression of haemoglobin-induced lipid peroxidation could be a previously unknown mechanism of IDR. Our study can help improve its application for UC treatment.

Lappaol F regulates the cell cycle by activating CDKN1C/p57 in human colorectal cancer cells

CONTEXT

Lappaol F (LAF), a natural lignan from Arctium lappa Linné (Asteraceae), inhibits tumor cell growth in vitro and in vivo. The underlying mechanism involves the suppression of the Yes-associated protein. However, the specific role of LAF in cell cycle regulation remains unknown.

OBJECTIVE

This study determined the molecular mechanism by which LAF regulates cell cycle progression.

MATERIALS AND METHODS

Various colon cancer cell lines (SW480, HCT15, and HCT116) were treated with LAF (25, 50, and 75 μmol/L) for 48 h. The effects of LAF on cell proliferation and cell cycle were determined using sulforhodamine B and flow cytometry assays. Differentially expressed proteins (DEPs) were identified using quantitative proteomics. Bioinformatic analysis of DEPs was conducted via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Expression levels of DEPs in the cell cycle pathway were analyzed using RT-qPCR and western blotting.

RESULTS

LAF suppressed the proliferation of SW480, HCT15, and HCT116 cells (IC₅₀ 47.1, 51.4, and 32.8 μmol/L, respectively) and induced cell cycle arrest at the S phase. A total of 6331 proteins were identified and quantified, of which 127 were differentially expressed between the LAF-treated and untreated groups. GO and KEGG enrichment analyses revealed that DEPs mainly participated in the cell cycle. CDKN1C/p57 showed the most significant differential expression, with the highest fold-change (3.155-fold). Knockdown of CDKN1C/p57 attenuated the S phase cell cycle arrest and proliferation inhibition induced by LAF.

CONCLUSION

LAF exerts antitumor effects via S phase arrest by activating CDKN1C/p57 in colorectal cancer cells.

Circadian-like patterns in electrochemical skin conductance measured from home-based devices: a retrospective study

In this study, we investigated the potential of electrochemical skin conductance (ESC) measurements gathered from home-based devices to detect circadian-like patterns. We analyzed data from 43,284 individuals using the Withings Body Comp or Body Scan scales, which provide ESC measurements. Our results highlighted a circadian pattern of ESC values across different age groups and countries. Our findings suggest that home-based ESC measurements could be used to evaluate circadian rhythm disorders associated with neuropathies and contribute to a better understanding of their pathophysiology. However, further controlled studies are needed to confirm these results. This study highlights the potential of digital health devices to generate new scientific and medical knowledge.

[Association between serum lysophosphatidylcholine level and elderly health index in older people from longevity areas of Guangxi Province]

Objective: To investigate the relationship between serum lysophosphatidylcholine (LPC) level and the health index of the elderly. Methods: A total of 251 subjects were selected from the 2016 baseline survey of the Yongfu Longevity Cohort in Guangxi Province among whom 66, 63 and 122 were in the young and middle-aged group (≤59 years old), the young group (60-89 years old) and the longevity group (≥90 years old), respectively. Demographic data were collected and related indicators of height, weight, blood pressure and lipid metabolism were measured. The cognitive and physical functions of the elderly were assessed by the results of the simple mental state scale and the daily living activity scale to construct the health index of the elderly. The serum levels of LPC16∶0, LPC18∶0, LPC18∶1 and LPC18∶2 were determined by liquid chromatography-tandem mass spectrometry, and the differences among different ages and health status groups were compared. The logistic regression model was used to analyze the relationship between the serum LPC level and the health index of the elderly. Results: With the increase in age, the proportion of female subjects increased, and the rate of smoking and drinking decreased. BMI, TC, TG, LDL-C, diastolic blood pressure, and the four LPCs levels decreased with the increase of age, and systolic blood pressure levels increased with the increase of age (all P values<0.05). There was no significant difference in HDL-C levels among age groups (P>0.05). With the decline of health status in the elderly, serum levels of LPC16∶0, LPC18∶0, LPC18∶1 and LPC18∶2 showed a downward trend (all P values<0.001). After adjusting for age and gender, only LPC18∶0 was associated with the health status in old age [OR (95%CI): 0.48 (0.25-0.92)]. For every 1 standard deviation (16.87 nmol/L) increase in serum LPC18∶0 concentration, the risk of poor health status in old age decreased by 52%. Conclusion: Serum LPC18∶0 was associated with the health status in old age independent of age and sex.

[Research progress on main disease-related factors of healthy life expectancy]

International research on healthy life expectancy (HALE) focuses on inequality of socioeconomic status and individual natural attributes. With the acceleration of population ageing and the increase in average life expectancy, the extension of unhealthy life expectancy and the increase of social and economic burden caused by diseases have gradually attracted the attention of countries around the world. Therefore, the evaluation of disease factors affecting HALE is a meaningful direction in the future. This study introduces the development process and commonly used measurement methods of HALE. According to the definition of health from the Global Burden of Disease Study and World Health Organization, physical and mental diseases such as cardiovascular and cerebrovascular diseases, chronic respiratory diseases, diabetes, malignant tumors and depression were selected to summarize the impact of these diseases and pre-disease states on HALE. It is expected to provide a theoretical basis for the formulation of relevant public health policies and the improvement of quality of life in China.

[Value of glycosylated hemoglobin A1c and apolipoprotein A-1 ratio on predicting outcome of patients with acute coronary syndrome]

Objective: To investigate the predictive value of glycosylated hemoglobin A1c/apolipoprotein A-1 (HbA1c/ApoA-1) ratio for major adverse cardiovascular events (MACEs) in patients with acute coronary syndrome (ACS). Methods: The present study is a retrospective cohort study. ACS patients who were hospitalized and underwent coronary angiography at Beijing Hospital from March 2017 to March 2019 were enrolled. Baseline information such as sex, age, previous history, Gensini score, HbA1c and ApoA-1 were analyzed. Patients were divided into two groups according to presence or absence of MACEs and the difference on HbA1c/ApoA-1 ratio was compared between the two groups. According to the tertiles of HbA1c/ApoA-1 levels, patients were divided into high (5.87-16.12), medium (4.50-5.83) and low (2.11-4.48) HbA1c/ApoA-1 groups. Cox proportional risk model was used to evaluate the differences in MACEs and all-cause mortality among the three groups. Kaplan-Meier survival analysis was used to compare the differences of MACEs between the various HbA1c/ApoA-1 groups. Results: A total of 366 ACS patients were included in this study. The mean age of the patients was (65.9±10.3) years. There were 59 MACEs and 10 all-cause deaths during the mean of (22.3±4.4) months follow-up. After adjusting for age, systolic blood pressure, history of diabetes and Gensini score, the incidence of MACEs was 2.45 times higher in the high HbA1c/ApoA-1 group than in the low HbA1c/ApoA-1 group (95%CI 1.16-5.18, P=0.019). There was no significant difference in all-cause mortality between the high and low HbA1c/ApoA-1 groups (P=1.000). Kaplan-Meier survival analysis showed that patients in the high HbA1c/ApoA-1 group had the highest risk of MACEs, while patients in the low HbA1c/ApoA-1 group had the lowest risk of MACEs (P<0.01). Spearman rank correlation analysis showed that HbA1/ApoA-1 ratio was positively correlated with Gensini score in ACS patients (r=0.274, P<0.01). Conclusion: High HbA1c/ApoA-1 ratio was an independent risk factor for MACEs in ACS patients. Patients with high HbA1c/ApoA-1 ratio had more severe coronary artery disease lesions. HbA1c/ApoA-1 ratio may be used as a potential risk stratification biomarker for ACS patients, it might be useful for the early identification of high-risk population and for predicting the incidence of MACEs among ACS patients.

An ester derivative of tenacigenin B from Marsdenia tenacissima (Roxb.) Wight et Arn reversed paclitaxel-induced MDR in vitro and in vivo by inhibiting both P-gp and MRP2

ETHNOPHARMACOLOGICAL RELEVANCE

Marsdenia tenacissima is a medicinal plant, used as a raw material for cancer treatment in China. In our previous studies, 11α-O-2-methylbutanoyl-12β-O-tigloyl-tenacigenin B (MT2), the main steroid aglycone isolated from M. tenacissima, was found to significantly enhance the antitumor activity of paclitaxel (PTX) in vivo. However, it is unclear whether MT2 reverses multidrug resistance (MDR) in tumors.

AIM OF THE STUDY

To determine the role and mechanism of MT2 in reversing tumor MDR.

MATERIALS AND METHODS

MDR cell line HeLa/Tax was established from the human cervical carcinoma cell line HeLa by long-term exposure to subtoxic concentrations of PTX and was used to evaluate the ability of MT2 to restore chemosensitivity of cells both in vitro and in a nude mouse model. The expression of P-glycoprotein (P-gp) and multidrug resistance-associated protein 2 (MRP2) was determined using western blotting and immunohistochemistry. The substrate transport function was assessed using an MDR function assay kit. The binding modes of MT2 and P-gp were determined using the conformation-sensitive anti-P-gp antibodies. The permeability and transport properties of MT2 were analyzed in Caco-2 cell monolayers.

RESULTS

Compared to parental cells, HeLa/Tax cells overexpress P-gp and MRP2 and are approximately 100-360 fold more resistant to the anticancer drugs PTX, docetaxel, and vinblastine. MT2 at 5 or 10 μmol/L significantly increased the sensitivity of HeLa/Tax to these three anticancer drugs (18-56-fold decrease in IC₅₀ value) and suppressed the expression of P-gp and MRP2. Knockdown of P-gp with small interfering RNA partially reversed MT2-induced sensitivity to PTX in HeLa/Tax cells. Moreover, MT2 directly inhibited P-gp-mediated substrate transport while interacting with membrane P-gp in non-substrate ways. MT2 was highly permeable and could not be transported in the Caco-2 cell monolayers. In nude mice bearing HeLa/Tax xenografts, the combination treatment with MT2 and PTX exerted a synergistic inhibitory effect on the growth of tumors and the expression of P-gp and MRP2 without increasing toxicity.

CONCLUSION

MT2 is a potential agent for reversing MDR. It impedes membrane drug efflux pumps by suppressing P-gp and MRP2 expression, and directly inhibiting the transport function of P-gp.

[Application of indocyanine green fluorescence visualization in surgical resection of abdominal wall endometriosis]

Objective: To investigate the feasibility, effectiveness and safety of indocyanine green (ICG) navigation in the surgical resection of abdominal wall endometriosis (AWE). Methods: Seven women undergoing surgery for AWE in First Affiliated Hospital of Sun Yat-sen University (from July 1, 2021 to October 1, 2021) were collected. After exposure of the focus, ICG were used intravenously (0.25 mg/kg) as fluorescent dye for the intraoperative evaluation of AWE vascularization. Resection of the AWE was guided by direct visualization of the focus under standard laparoscopy with a near-infrared (NIR) camera head. Surgical margin around the AWE (3, 6, 9 and 12 point) and the margin under the focus were obtained for postoperative pathological examination of endometriosis. Time from injection to fluorescence visualization, the proportion of fluorescence visualization, time of fully resection of AWE, side effects related to the use of ICG, perioperative complications as well as the pathological result of the surgical margins were recorded. Results: ICG fluorescence of the AWE were seen in 5 patients (5/7). The mean time from injection to fluorescence visualization was (46.7±9.8) s. The mean time of fully resection of AWE was (16.4±7.0) minutes. There were no side effects related to the use of ICG. The rate of class-A wound healing was 7/7. All of the surgical margins were confirmed endometriosis-negative by postoperative pathological examination. Conclusion: ICG fluorescence visualization could conduct accurate resection of AWE, which is clinically safe and effective.

Lappaol F, an anticancer agent, inhibits YAP via transcriptional and post-translational regulation

CONTEXT

Lappaol F (LAF), a natural lignan from Arctium lappa Linné (Asteraceae), inhibits tumour cell growth by inducing cell cycle arrest. However, its underlying anticancer mechanism remains unclear.

OBJECTIVE

The effects of LAF on the Hippo-Yes-associated protein (YAP) signalling pathway, which plays an important role in cancer progression, were explored in this study.

MATERIALS AND METHODS

Cervical (HeLa), colorectal (SW480), breast (MDA-MB-231) and prostate (PC3) cancer cell lines were treated with LAF at different concentrations and different durations. BALB/c nude mice bearing colon xenografts were intravenously injected with vehicle, LAF (10 or 20 mg/kg) or paclitaxel (10 mg/kg) for 15 days. The expression and nuclear localisation of YAP were analysed using transcriptome sequencing, quantitative PCR, western blotting and immunofluorescence.

RESULTS

LAF suppressed the proliferation of HeLa, MDA-MB-231, SW480 and PC3 cells (IC₅₀ values of 41.5, 26.0, 45.3 and 42.9 μmol/L, respectively, at 72 h), and this was accompanied by significant downregulation in the expression of YAP and its downstream target genes at both the mRNA and protein levels. The expression of 14-3-3σ, a protein that causes YAP cytoplasmic retention and degradation, was remarkably increased, resulting in a decrease in YAP nuclear localisation. Knockdown of 14-3-3σ with small interfering RNA partially blocked LAF-induced YAP inhibition and anti-proliferation effects. In colon xenografts, treatment with LAF led to reduced YAP expression, increased tumour cell apoptosis and tumour growth inhibition.

CONCLUSION

LAF was shown to be an inhibitor of YAP. It exerts anticancer activity by inhibiting YAP at the transcriptional and post-translational levels.

[Plasm trimethylamine-N-oxide level and association with lesion severity in coronary heart disease patients with type 2 diabetes mellitus]

Objective: To investigate the association between trimethylamine-N-oxide (TMAO) and the degree of coronary atherosclerosis in coronary heart diseases (CHD) patients with type 2 diabetes mellitus. Methods: Consecutive patients, who underwent coronary angiography due to suspected CHD in Beijing Hospital from November 2016 to January 2018, were screened in this cross-sectional study. According to blood glucose level, previous medical history and coronary angiography results, they were divided into CHD without type2 diabetes mellitus(CHD-nDM) group and CHD with type2 diabetes mellitus(CHD-DM) group. Plasma TMAO levels in each group were measured by LC-MS/MS. Spearman correlation analysis was used to evaluate the correlation between TMAO and the number of diseased vessels and Gensini scores. Multivariate logistic regression was used to analyze the correlation between TMAO and high Gensini scores. Results: A total of 590 patients were enrolled in the study, including 238 patients in CHD-DM group and 352 patients in CHD-nDM group. Patients were older, body mass index, blood pressure level, prevalence of history of hypertension and statins use were higher in CHD-DM group than in CHD-nDM group (all P<0.05). The proportion of patients with multivessel disease (2 or more vessels) was also higher in CHD-DM group than in CHD-nDM group (P<0.001). Gensini score was higher in CHD-DM group than in CHD-nDM group (P<0.05). Fasting blood glucose, glycosylated hemoglobin and urea were significantly higher, while low-density lipoprotein cholesterol and hemoglobin were significantly lower in CHD-DM group than in CHD-nDM group (all P<0.05). The levels of TMAO was significantly higher in CHD-DM group than in CHD-nDM group (P<0.001). Spearman correlation analysis showed that TMAO was positively correlated with the number of diseased vessels, Gensini score, age and blood glucose level (r=0.178, 0.189, 0.260, 0.111, respectively, all P<0.01). Multivariate logistic regression analysis showed that, TMAO level was still positively correlated with high Gensini score in CHD-DM group (OR=2.25, 95%CI 1.16-4.38, P=0.017), but not in CHD-nDM group (OR=1.29, 95%CI 0.72-2.31, P=0.386) after adjusting for age, sex, body mass index, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, total cholesterol, triglyceride, history of hypertension, hyperlipidemia, smoking and statin use. Conclusions: In CHD patients with tupe 2 diabetes mellitus, the plasma TMAO level is significantly increased and is independent and positively correlated with the degree of coronary artery disease.

Validation of the Withings Sleep Analyzer, an under-the-mattress device for the detection of moderate-severe sleep apnea syndrome

STUDY OBJECTIVES

To assess the diagnostic performance of a nonintrusive device placed under the mattress to detect sleep apnea syndrome.

METHODS

One hundred eighteen patients suspected to have obstructive sleep apnea syndrome completed a night at a sleep clinic with a simultaneous polysomnography (PSG) and recording with the Withings Sleep Analyzers. PSG nights were scored twice: first as simple polygraphy, then as PSG.

RESULTS

Average (standard deviation) apnea-hypopnea index from PSG was 31.2 events/h (25.0) and 32.8 events/h (29.9) according to the Withings Sleep Analyzers. The mean absolute error was 9.5 events/h. The sensitivity, specificity, and area under the receiver operating characteristic curve at thresholds of apnea-hypopnea index ≥ 15 events/h were, respectively, sensitivity (Se)₁₅ = 88.0%, specificity (Sp)₁₅ = 88.6%, and area under the receiver operating characteristic curve (AUROC) ₁₅ = 0.926. At the threshold of apnea-hypopnea index ≥ 30 events/h, results included Se₃₀ = 86.0%, Sp₃₀ = 91.2%, AUROC₃₀ = 0.954. The average total sleep time from PSG and the Withings Sleep Analyzers was 366.6 (61.2) and 392.4 (67.2) minutes, sleep efficiency was 82.5% (11.6) and 82.6% (11.6), and wake after sleep onset was 62.7 (48.0) and 45.2 (37.3) minutes, respectively.

CONCLUSIONS

Withings Sleep Analyzers accurately detect moderate-severe sleep apnea syndrome in patients suspected of sleep apnea syndrome. This simple and automated approach could be of great clinical value given the high prevalence of sleep apnea syndrome in the general population.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Validation of Withings Sleep for the Detection of Sleep Apnea Syndrome; URL: https://clinicaltrials.gov/ct2/show/NCT04234828; Identifier: NCT04234828.

[Dysregulated proportion of intrahepatic Treg cells and Th17 along with CD8+ T lymphocytes drives disease progression after kasai biliary atresia surgery]

Objective: To analyze the clinicopathological characteristics and intrahepatic immune cells infiltration condition after Kasai biliary atresia surgery. Methods: Data of 28 cases who underwent liver transplantation in the liver transplantation center of our hospital from June 2017 to March 2019 were enrolled. Of which, 20 cases were in the biliary atresia group (divided into two subgroups: 10 cases without Kasai surgery and 10 cases after Kasai surgery, and latter subsided cholestasis) and 8 cases in the control group. Clinical and pathological morphological characteristics of the groups were compared. Liver tissue sections were stained with immunohistochemistry and CD3, CD4, CD8, CD20, Foxp3, and interleukin-17A were quantitatively analyzed. Kruskal-Wallis test was used to measure the above indicators, and rank-sum test or Fisher's exact test was used to compare the count data. Results: The degree of clinical and pathological cholestasis in the biliary atresia group after Kasai surgery was significantly lower than that of the group without Kasai surgery, and the degree of liver fibrosis was also significantly reduced (P < 0.05), but there was no statistically significant difference in the degree of inflammation in the portal vein area between the two groups (P > 0.05). There was statistically significant difference in the types of immune cells infiltrated in the liver (P < 0.05). Compared with the group without Kasai surgery, the infiltration of CD3, CD8, IL-17A and Foxp3 positive cells in the portal vein area after Kasai surgery group (P < 0.05) was significantly reduced, but there was no statistically significant difference in the proportion of Foxp3/CD4 positive cells between the two groups (P > 0.05), which continued to be lower than that of the control group (P < 0.05). Compared with the non-Kasai surgery group, the proportion of Foxp3/IL-17A and Foxp3/CD8 positive cells in the portal vein area did not increase significantly after Kasai surgery group (P > 0.05), and remained lower than the control group. However, the proportion of Foxp3/IL-17A and Foxp3/CD8 positive cells was significantly reduced (P ​​< 0.05). Conclusion: Intrahepatic inflammatory cell infiltration and regulatory/effector T lymphocyte proportion dysregulation exist in patients with subsided cholestasis after Kasai biliary atresia surgery, which may be an important factor to promote the disease progression.

Cajanolactone A, a stilbenoid from cajanus cajan, prevents ovariectomy-induced obesity and liver steatosis in mice fed a regular diet

BACKGROUND

Visceral obesity and fatty liver are prevalent in postmenopausal women. The stilbene-rich extract of Cajanus cajan (L.) Millsp. has been reported to prevent ovariectomy-induced and diet-induced weight gain in animal models, and stilbenoids from C. cajan are thought to have the potential to prevent postmenopausal obesity and fatty liver.

PURPOSE

Cajanolactone A (CLA) is the main stilbenoid from C. cajan with osteoblastogenic promoting activity. This study investigated the potential of CLA to prevent postmenopausal obesity and fatty liver. Underlying mechanisms were also investigated.

METHOD

Ovariectomized C57BL/6 mice fed a regular diet were used as mimics of postmenopausal women and given 10, 20, or 40 mg/kg/d of CLA, 0.1 mg/kg/d of estradiol valerate (EV, positive control), or vehicle (OVX) orally for 16 weeks. Mice of the same age subjected to a sham operation were used as control (Sham). Body weights were recorded every 2 weeks for 16 weeks. Body compositions were analyzed via micro-CT. Serum levels of lipids, adipocytokines and aminotransferases were measured using the relevant kits. mRNA levels of genes of interest were detected by RT-qPCR. Proteomic study of perigonadal white adipose tissue (pWAT) was performed using tandem-mass-tags-based proteomic technology combined with Parallel-Reaction-Monitoring (PRM) validation.

RESULTS

CLA showed potential equivalent to that of EV to prevent ovariectomy-induced overweight, obesity, dyslipidemia, liver steatosis and liver dysfunction, but did not prevent uterine atrophy. In the liver, CLA significantly inhibited ovariectomy-induced upregulation in expression of lipogenic genes SREBP-1c and ChREBP, and stimulated the mRNA expression of apolipoprotein B gene ApoB. In pWAT, CLA reversed, or partially reversed ovariectomy-induced downregulation in the expression of a number of metabolism- and mitochondrial-function-related proteins, including Ndufa3, Pcx, Pdhb, Acly, Acaca, Aldh2, Aacs and Echs1. In addition, ovariectomy-inhibited mRNA expression of Pdhb, Aacs, Acsm5, Echs1, and Aldh2 genes in pWAT was also reversed.

CONCLUSION

CLA was demonstrated to be a potential non-estrogen-like drug candidate for prevention of postmenopausal obesity and fatty liver. The underlying mechanism might involve the inhibition of lipogenesis and promotion of triglycerides output in the liver, and the promotion of metabolism and mitochondrial functions of visceral white adipose tissue.

Wearable Activity Trackers for Monitoring Adherence to Home Confinement During the COVID-19 Pandemic Worldwide: Data Aggregation and Analysis

Background

In the context of home confinement during the coronavirus disease (COVID-19) pandemic, objective, real-time data are needed to assess populations’ adherence to home confinement to adapt policies and control measures accordingly.

Objective

The aim of this study was to determine whether wearable activity trackers could provide information regarding users' adherence to home confinement policies because of their capacity for seamless and continuous monitoring of individuals’ natural activity patterns regardless of their location.

Methods

We analyzed big data from individuals using activity trackers (Withings) that count the wearer’s average daily number of steps in a number of representative nations that adopted different modalities of restriction of citizens’ activities.

Results

Data on the number of steps per day from over 740,000 individuals around the world were analyzed. We demonstrate the physical activity patterns in several representative countries with total, partial, or no home confinement. The decrease in steps per day in regions with strict total home confinement ranged from 25% to 54%. Partial lockdown (characterized by social distancing measures such as school closures, bar and restaurant closures, and cancellation of public meetings but without strict home confinement) does not appear to have a significant impact on people’s activity compared to the pre-pandemic period. The absolute level of physical activity under total home confinement in European countries is around twofold that in China. In some countries, such as France and Spain, physical activity started to gradually decrease even before official commitment to lockdown as a result of initial less stringent restriction orders or self-quarantine. However, physical activity began to increase again in the last 2 weeks, suggesting a decrease in compliance with confinement orders.

Conclusions

Aggregate analysis of activity tracker data with the potential for daily updates can provide information regarding adherence to home confinement policies.

[Personalized repeat Gamma Knife Radiosurgery treatment in patients with recurrent refractory trigeminal neuralgia]

Objective: To analyze the prognosis and untoward effect in recurrent refractory trigeminal neuralgia (RRTN) patients who underwent repeat Gamma Knife Radiosurgery treatment (GKRS) retrospectively, and to summarize the experience of repeat Gamma Knife Radiosurgery treatment of recurrent refractory trigeminal neuralgia. Methods: RRTN patients who treated with repeat GKRS during 1998.8.1 to 2014.10.1 in Gamma Knife treatment Center of the Fifth Affiliated Hospital of Zhengzhou University were involved. The factors influencing long-term prognosis and facial numbness adverse reactions were statistically analyzed. Results: Therapeutic dose was an independent factor that influence long-term prognosis of RRTN patients. Therapeutic dose was a dangerous factor that influence long-term facial numbness. Interval time between twice GKRS treatment was a favorable factor for facial numbness. Long-term prognosis of repeat GKRS treatment was positively correlated with therapeutic dose. Untoward effect of facial numbness after repeat GKRS treatment was positively correlated with therapeutic dose and negatively correlated with interval time between twice GKRS treatment. Conclusions: Repeat GKRS for RRTN patients is safe and effective, but personalized treatment plan should be given according to the patient's own condition.

Identification of serum metabolites associated with obesity and traditional risk factors for metabolic disease in Chinese adults

BACKGROUND AND AIMS

Obesity is a major worldwide health problem and is often associated with many metabolic diseases. Levels of several serum-specific metabolites may be altered in patients with these metabolic diseases. We aimed to investigate the associations of serum metabolite levels with obesity and traditional risk factors for metabolic disease in Chinese individuals.

METHODS AND RESULTS

Six-hundred Chinese individuals undergoing annual physical exams were recruited and categorized into overweight/obese and control groups (1:1 ratio). We simultaneously quantified the serum lysophosphatidylcholine (LPC), branched-chain amino acids (BCAA), aromatic amino acids (AAA), 25-hydroxyvitamin D, glutamine (Gln), glutamic acid (Glu), and Gln/Glu ratio levels using our previously established targeted serum metabolomic method. The overweight/obesity group had significantly higher levels of BCAA, AAA, and Glu, as well as lower levels of unsaturated LPC, Gln, and Gln/Glu, than the control group. Correlation analyses revealed significant and positive relationships of saturated LPC, BCAA, AAA, and Glu with blood pressure, glucose, triglycerides, apolipoprotein B, and high-sensitivity C-reactive protein, while unsaturated LPC, Gln, Gln/Glu, and 25-hydroxyvitamin D exhibited an opposite trend. In the multifactor logistic regression model, low unsaturated LPC and Gln/Glu, as well as high BCAA and AAA levels, were found to be independent risk factors for obesity; the odds ratios (95% confidence interval) of the highest quartile compared to the lowest quartile were 0.241 (0.139-0.417), 0.436 (0.252-0.755), 3.944 (2.094-7.430), and 2.357 (1.274-4.361) (P < 0.01), respectively.

CONCLUSION

LPC, BCAA, AAA, and Gln/Glu are significantly related to obesity development and risk factors of some metabolic diseases.

Association of branched-chain amino acids with coronary artery disease: A matched-pair case-control study

BACKGROUND AND AIM

Several recent studies have found an independent relationship between levels of plasma branched-chain amino acids (BCAAs) and risk factors for coronary artery disease (CAD); however, few studies have investigated the associations of BCAAs with CAD and the risk of cardiovascular events. Therefore, the aim of this study was to investigate the relationship between BCAAs and CAD.

METHODS AND RESULTS

We studied 143 patients with CAD diagnosed by coronary angiography at Beijing Hospital (Beijing, China) during 2008-2011. Apparently healthy control individuals (n = 286) and the patients with CAD were matched (2:1 ratio) by age and gender. The healthy control individuals were selected at random from a set of subjects who attended an annual physical examination at the same hospital in 2011. Conditional logistic regression models were used to evaluate the associations between measured variables and CAD. After multivariate adjustment for traditional CAD risk factors, each one-standard-deviation increase in BCAA concentration was associated with an approximately twofold increase in the risk of CAD (odds ratio = 1.63, 95% confidence interval (CI): 1.21-2.20, P = 0.001). As compared with subjects in the lowest quartile of BCAA levels, the odds ratios (95% CIs) for CAD risk in subjects belonging to quartiles 2, 3, and 4 were 1.65 (0.75-3.61), 2.04 (0.92-4.53), and 3.86 (1.71-8.69), respectively (P trend = 0.01).

CONCLUSION

Our results demonstrate that BCAAs are significantly related to CAD development. This relationship is independent of diabetes, hypertension, dyslipidemia, and body mass index.

Senescent leaves of Artemisia annua are one of the most active organs for overexpression of artemisinin biosynthesis responsible genes upon burst of singlet oxygen

To dissect and penetrate complexicity regarding the tissue-specific and environment-induced expression modes of cytosolic and plastidial terpene biosynthetic genes in A. annua, corresponding mRNAs relevant to terpene biosynthesis were quantitatively compared among distinctive organs and during different growth stages. Although all examined mRNAs gradually elevate from June to August in tested organs, a putative artemisinin biosynthesis responsible DBR2 mRNA represents the most abundant transcript anyplace and anytime. Apart from others, senescent leaves endow global activation of artemisinin biosynthetic genes and ultimately lead to enhanced artemisinin production. Direct measurement of (1)O (2) burst from senescent leaves strongly supports an involvement of (1)O (2) in conversion from precursor(s) to artemisinin. In the context of environmental stresses, physical and chemical stress signals that include those invoking (1)O (2) burst were evaluated as if inducing artemisinin biosynthetic genes. The quantitative data have reiterated a common pattern of modulating artemisinin production in A. annua by triggering (1)O (2) burst during senescence and under chilling acclimatization. In conclusion, a missing link concatenating senescence-coupled (1)O (2) generation to (1)O (2)-induced upregulation of artemisinin biosynthetic genes has been re-established, which would provide a fertile base for future endeavors pursuing further enhancements of artemisinin production.

Quantitative transcript profiling reveals down-regulation of A sterol pathway relevant gene and overexpression of artemisinin biogenetic genes in transgenic Artemisia annua plants

To investigate the dynamic fluctuation of terpenoid relevant transcriptomics in transgenic ARTEMISIA ANNUA plants that express the genomic integrated antisense squalene synthase gene ( ASSS), we have quantified the transcript levels of the sterol anabolic SS gene as well as artemisinin biogenetic amorphadiene synthase (ADS), cytochrome P450 monooxygenase (CYP71AV1) and cytochrome P450 reductase (CPR) genes by real-time fluorescent quantitative polymerase chain reaction (RFQ-PCR). The SS mRNA level in transgenic plants sharply droped to 7.4 % - 55.3 % (i. e., 44.7 - 92.6 % reduction as the wild-type control), strongly implying that the expression of endogenous SS gene is significantly suppressed by the exogenous ASSS gene. In a synchronous fashion, ADS, CYP71AV1 and CPR mRNA levels elevated with the decline of SS mRNA level in transgenic plants, and the maximal ADS, CYP71AV1 and CPR mRNA levels in transgenic plants were 3.0-, 4.4- and 2.5-fold, respectively, higher than those in the control. Without a lethal effect but with a distinguishable impact on the organogenesis and morphology of transgenic plants, the down-regulation of SS gene has also led to the coordinated overexpression of ADS, CYP71AV1 and CPR genes together with the overproduction of artemisinin although no fully perfect correlation among the available experimental data has been shown.

Characterization of interparticle forces in the packing of cohesive fine particles

We numerically investigate force structures in the packing of fine cohesive particles using the discrete element method. By changing the particle size and therefore the van der Waals force, the effect of cohesion on the normal contact force and the total normal force, which is the sum of the normal contact forces and the van der Waals forces, is analyzed. It is shown that, with decreasing particle size, the normal contact forces become more uniform and have a narrower and more symmetric distribution, while the distributions of the total normal forces widen. Spatial correlation between the interparticle forces exists for the packing of coarse noncohesive particles. As the particle size decreases, this correlation becomes weaker for the contact forces but stronger for the total normal forces. A comparison between the effective weight of particles and the internal force structure suggests that there are differences between the particle-particle and particle-wall forces. The bimodal distribution of the effective weight indicates that there may exist two phases in the packings when cohesion is present, governed by the compressive and tensile stresses.

A Quantitative Assay of Recombinant Malarial Lactate Dehydrogenase as a Platform for Screening Inhibitors from Crude Herbal Extracts

To establish a platform for high throughput screening and in vitro evaluating novel metabolic enzyme-targeted inhibitors towards anti-malarial drugs, a lactate dehydrogenase gene of Plasmodium falciparum (PfLDH) was amplified from the Hainan isolate FCC1/HN. The fusion expression vectors, pGEX-2TK and pET-29a( + ), were utilized to introduce the PfLDH gene into strains of Escherichia coli, BL21 and BL21 (DE3), for over-expression. Consequently, the enzymatic activity of PfLDH was successfully detected in the suspension of lytic bacteria. The PfLDH gene cloned in pGEX-2TK was mainly expressed as inclusion bodies, while the same gene cloned in pET-29a( + ) was nearly expressed in a soluble form of PfLDH, demonstrating the latter vehicle might be more suitable for the large-scale preparation of recombinant PfLDH. Furthermore, according to the electrophoregram of SDS-PAGE and the sequencing data, a series of truncated PfLDH sequences generated randomly from gene amplification were screened and cloned, from which four pre-matured genes with a terminator mutation, PfLDH-delta271, -delta236, -delta167 and -delta53 coding for 45, 80, 149 and 263 amino acid residues, were individually recovered. Through the gene expression and enzymatic activity measurement, the effect of pre-matured terminator mutation on the activity of PfLDH was evaluated, which should pave the way for probing the relationship between structure and function of PfLDH.

Self-assembly of particles for densest packing by mechanical vibration

It is shown that by properly controlling vibrational and charging conditions, the transition from disordered to ordered, densest packing of particles can be obtained consistently. The method applies to both spherical and nonspherical particles. For spheres, face centered cubic packing with different orientations can be achieved by monitoring the vibration amplitude and frequency, and the structure of the bottom layer, in particular. The resultant force structures are ordered but do not necessarily correspond to the packing structures fully. The implications of the findings are also discussed.

Pore structure of the packing of fine particles

This paper presents a numerical study of the pore structure of fine particles. By means of granular dynamics simulation, packings of mono-sized particles ranging from 1 to 1000 microm are constructed. Our results show that packing density varies with particle size due to the effect of the cohesive van der Waals force. Pores and their connectivity are then analysed in terms of Delaunay tessellation. The geometries of the pores are represented by the size and shape of Delaunay cells and quantified as a function of packing density or particle size. It shows that the cell size decreases and the cell shape becomes more spherical with increasing packing density. A general correlation exists between the size and shape of cells: the larger the cell size relative to particle size, the more spherical the cell shape. This correlation, however, becomes weaker as packing density decreases. The connectivity between pores is represented by throat size and channel length. With decreasing packing density, the throat size increases and the channel length decreases. The pore scale information would be useful to understand and model the transport and mechanical properties of porous media.

Role of interparticle forces in the formation of random loose packing

We present a physical and numerical study of the settling of uniform spheres in liquids and show that interparticle forces play a critical role in forming the so-called random loose packing (RLP). Different packing conditions give different interparticle forces and, hence, different RLP. Two types of interparticle forces are identified: process dependent and process independent. The van der Waals force, as the major cohesive force in the present study, plays a critical role in effecting the process-dependent forces such as drag and lift forces. An equation is formulated to describe the relationship between the macroscopic packing fraction and microscopic interparticle forces in a packing. We argue there is no lowest packing fraction for a mechanically stable RLP; hence, the packing fractions of RLP can range from 0 to 0.64 depending on the cohesive and frictional conditions between particles.

Micromechanical simulation and analysis of one-dimensional vibratory sphere packing

We present a numerical method capable of reproducing the densification process from the so-called random loose to dense packing of uniform spheres under vertical vibration. The effects of vibration amplitude and frequency are quantified, and the random close packing is shown to be achieved only if both parameters are properly controlled. Two densification mechanisms are identified: pushing filling by which the contact between spheres is maintained and jumping filling by which the contact between particles is periodically broken. In general, pushing filling occurs when the vibration intensity is low and jumping filling becomes dominant when the vibration intensity is high.

Mutations outside the YMDD motif in the P protein can also cause DHBV resistant to Lamivudine

AIM: To observe the Lamivudine resistance character of a DHBV strain in vitro and in vivo, and to analyze if the Lamivudine resistance character is caused by gene mutation or by abnormity of the Lamivudine metabolism.

METHODS: Congenitally DHBV-negative Guangdong brown ducks and duck embryo liver cells were respectively taken as animal and cell model. The Lamivudine-susceptive DHBV and Lamivudine-resistant DHBV (LRDHBV) were infected and Lamivudine was administrated according to the divided groups. The changes of DHBV quantity in the animal and cell model were tested. Three Lamivudine-resistant and two Lamivudine-susceptive DHBV complete genomes were successfully amplified, sequenced and then submitted to GenBank. All the DHBV complete sequences in the GenBank at present were taken to align with the three LRDHBV to analyze the mutational points related to the Lamivudine-resistant mutation.

RESULTS: Both the animal and cell model showed that the large and the small dosage Lamivudine have no significant inhibitory effect on the LRDHBV. Five sequences of DHBV complete genomes were successfully cloned. The GenBank accession numbers of the three sequences of LRDHBV are AY521226, AY521227, and AY433937. The two strains of Lamivudine-susceptive DHBV are AY392760 and AY536371. The correlated mutational points are KorR86Q and AorE591T in the P protein.

CONCLUSION: The Lamivudine resistance character of this DHBV strain is caused by genome mutation; the related mutational points are KorR86Q and AorE591T and have no relations with the YMDD motif mutation.

Evaluation on expression of the recombinant S gene of human hepatitis B virus in vitro and in vivo

OBJECTIVES

To construct a DNA vaccine capable of expressing the S gene of hepatitis B virus (HBV) and evaluate the expression of the recombinant S gene in vitro and in vivo.

METHODS

A cloned S-X gene fragment was inserted into an eukaryote expression vector to construct a recombinant expressing plasmid pCMV-SX. The recombinant plasmid was transcribed in vitro with a T7 promoter transcription system and transfected into a human hepatoblastoma cell line HepG2. The expression of the S gene was detected by Northern blot hybridization, Western blot hybridization, and enzyme-linked immunosorbent assay (ELISA), respectively. BALB/c mice were inoculated with the recombinant plasmid, and the efficiency of DNA-based immunization in eliciting anti-HBs was evaluated by ELISA.

RESULTS

In vitro transcription of the subcloned HBV S gene was confirmed by Northern blot hybridization. The results of Western blot hybridization and ELISA showed that the S gene was expressed exactly in HepG2. In immune experiment, 2 of 10 immunized mice were shown to induce antibody against HBsAg.

CONCLUSION

The recombination and expression of the S gene can be achieved successfully in vitro. And the recombinant plasmid is able to elicit humoral immune response in mice.

[Establishment of stably expressed human RANTES gene in prunella vulgaris cell clone]

To express interesting human genes in herbal cells for boosting their specific pharmacological activities, RANTES gene cloned from human peripheral blood lymphocyte (PBL) mRNA was introduced into A. tumefaciens strain LBA4404 harboring pAL4404 plasmid via tumor-inducing (Ti) plasmid-derived intermediate expression vector pROKII. In vitro cultured P. vulgaris cells were transformed by leaf-disk cocultivation procedure. Integration of RANTES gene in the genome of transformed cells was confirmed by Southern blotting, and expression of RANTES gene in transformed cells was analyzed by RT-PCR amplification, Western blotting and enzyme-linked immunosorbent assay (ELISA). The peroxidase activity of PBL was utilized as a detection index of cellular chemotropism induction by recombinant RANTES. The results have shown the RANTES gene was integrated in transgenic P. vulgaris cells, and RANTES gene-stably expressed cell clones were available, which could pave the way to obtain transgenic P. vulgaris plants demonstrating specific pharmacological activities.

Galectins in cell growth and apoptosis

Fourteen members of the galectin family, proteins with conserved carbohydrate-recognition domains that bind beta-galactoside, have been cloned and more are expected to be discovered in the near future. Many aspects of galectin biology have been thoroughly explored, and functional studies have implicated these proteins in cell growth, differentiation and apoptosis, in addition to cell adhesion, chemoattraction and cell migration. In some cases a galectin can either promote or suppress cell growth, depending on the cell types and doses used. Galectin-3 is the only member known so far to inhibit apoptosis, while galectin-1, -7 and -9 promote this cellular process. Galectins can act either extracellularly or intracellularly to exert effects on cell growth and apoptosis.

Voronoi tessellation of the packing of fine uniform spheres

The packing of uniform fine spherical particles ranging from 1 to 1000 microm has been simulated by means of discrete particle simulation. The packing structure is analyzed, facilitated by the well established Voronoi tessellation. The topological and metric properties of Voronoi polyhedra are quantified as a function of particle size and packing density. The results show that as particle size or packing density decreases, (i) the average face number of Voronoi polyhedra decreases, and the distributions of face number and edge number become broader and more asymmetric; (ii) the average perimeter and area of polyhedra increase, and the distributions of polyhedron surface area and volume become more flat and can be described by the log-normal distribution. The topological and metric properties depicted for the packing of fine particles differ either quantitatively or qualitatively from those reported in the literature although they all can be related to packing density. In particular, our results show that the average sphericity coefficient of Voronoi polyhedra varies with packing density, and although Aboav-Weaire's law is generally applicable, Lewis's law is not valid when packing density is low, which are contrary to the previous findings for other packing systems.

Cell cycle regulation by galectin-12, a new member of the galectin superfamily

Galectins are a family of beta-galactoside-binding animal lectins with conserved carbohydrate recognition domains (CRDs). Here we report the identification and characterization of a new galectin, galectin-12, which contains two domains that are homologous to the galectin CRD. The N-terminal domain contains all of the sequence elements predicted to form the two beta-sheets found in other galectins, as well as conserved carbohydrate-interacting residues. The C-terminal domain shows considerable divergence from the consensus sequence, and many of these conserved residues are not present. Nevertheless, the protein has lactose binding activity, most likely due to the contribution of the N-terminal domain. The mRNA for galectin-12 contains features coding for proteins with growth-regulatory functions. These include start codons in a context that are suboptimal for translation initiation and AU-rich motifs in the 3'-untranslated region, which are known to confer instability to mRNA. Galectin-12 mRNA is sparingly expressed or undetectable in many tissues and cell lines tested, but it is up-regulated in cells synchronized at the G(1) phase or the G(1)/S boundary of the cell cycle. Ectopic expression of galectin-12 in cancer cells causes cell cycle arrest at the G(1) phase and cell growth suppression. We conclude that galectin-12 is a novel regulator of cellular homeostasis.

[Cloning, sequencing and in vitro expression of human RANTES gene]

An expected 276 bp fragment of the gene precursor encoding the signal peptide and mature protein of human beta-chemokine RANTES was amplified by reverse transcription-polymerase chain reaction (RT-PCR) from RNA of PHA-activated human peripheral blood lymphocytes. This putative interested gene was inserted directly into a T-vector and the ligation was confirmed by restriction enzyme digestion. The sequence data of the cloned fragment showed that it was almost identical with published sequences of RANTES gene, except for only one nucleotide substitution within the signal peptide region. The in vitro expressed recombinant RANTES protein was detected by the chemiluminescence enzyme-linked immune Dot blotting assay after combining the recombinant plasmid with the in vitro SP6/T7 transcription and translation system. The successful cloning and expression of RANTES gene should shed light on future's gene therapy of AIDS.

Computer simulation of the packing of fine particles

This paper presents a simulation study of the packing of uniform fine-spherical particles where the van der Waals force is dominant. It is shown that porosity increases with the decreases of particle size from about 100 to 1 &mgr;m and the simulated relationship can match the literature data well. The packing structure of fine particles is qualitatively depicted by illustrative pictures and quantified in terms of radial distribution function, angular distribution, and coordination number. The results indicate that in line with the increase in porosity, the first component of the split second peak and then the other peaks beyond the second one in the radial distribution function gradually vanish; the first peak becomes narrower, with a sharp decrease to the first minimum. As particle size decreases, the peaks at 120 degrees and then 60 degrees in the angular distribution will gradually vanish; the coordination number distribution shifts to the left and becomes narrower. The mean coordination number can decrease to a value as low as two for 1 &mgr;m particles, giving a very loose and chainlike structure. The interparticle forces acting on individual particles in a stable packing are analyzed and shown to be related to the packing properties.

Targeted disruption of the galectin-3 gene results in attenuated peritoneal inflammatory responses

Galectin-3 is a member of a growing family of beta-galactoside-binding animal lectins. Previous studies have demonstrated a variety of biological activities for this protein in vitro, including activation of cells, modulation of cell adhesion, induction of pre-mRNA splicing, and regulation of apoptosis. To assist in fully elucidating the physiological and pathological functions of this protein, we have generated galectin-3-deficient (gal3(-/-)) mice by targeted interruption of the galectin-3 gene. Gal3(-/-) mice consistently developed fewer inflammatory cell infiltrations in the peritoneal cavities than the wild-type (gal3(+/+)) mice in response to thioglycollate broth treatment, mainly due to lower numbers of macrophages. Also, when compared to cells from gal3(+/+) mice, thioglycollate-elicited inflammatory cells from gal3(-/-) mice exhibited significantly lower levels of NF-kappaB response. In addition, dramatically different cell-spreading phenotypes were observed in cultured macrophages from the two genotypes. Whereas macrophages from gal3(+/+) mice exhibited well spread out morphology, those from gal3(-/-) mice were often spindle-shaped. Finally, we found that peritoneal macrophages from gal3(-/-) mice were more prone to undergo apoptosis than those from gal3(+/+) mice when treated with apoptotic stimuli, suggesting that expression of galectin-3 in inflammatory cells may lead to longer cell survival, thus prolonging inflammation. These results strongly support galectin-3 as a positive regulator of inflammatory responses in the peritoneal cavity.

Asymmetric synthesis of L-azetidine-2-carboxylic acid and 3-substituted congeners--conformationally constrained analogs of phenylalanine, naphthylalanine, and leucine

Enantiopure L-azetidine-2-carboxylic acid, the (3R)-phenyl, (3R)-naphthyl and (3S)-isopropyl analogs were prepared based on a zinc-mediated asymmetric addition of allylic halides to the camphor sultam derivative of glyoxylic acid O-benzyl oxime.

Galectin-3 expression is induced in cirrhotic liver and hepatocellular carcinoma

Galectins are a family of beta-galactoside-binding animal lectins. In particular, a widely studied member galectin-3, previously designated as epsilonBP, CBP35, Mac-2, L-29 and L-34, has been associated with assorted processes such as cell growth, tumor transformation and metastasis. Galectin-3 is expressed in various tissues and organs but is significantly absent in normal hepatocytes. However, evaluation of patient liver biopsies for galectin-3 expression resulted in the finding that hepatocellular carcinoma (HCC) frequently expressed significant levels of this lectin (76% immunohistochemically positive). Further investigation revealed that galectin-3 expression in HCC is independent of whether the patient had prior hepatitis B virus infection: 14 of 18 HCC cases from HBV- patients, and 5 of 7 cases from HBV patients demonstrated positive galectin-3 immunohistochemistry. However, co-transfection studies using a galectin-3 promoter construct and an HBV-X protein (HBV-X) expression vector demonstrated that galectin-3 expression can occur through transactivation of the lectin promoter by HBV-X. Based on presently known properties of this lectin, it is possible that deregulated expression of galectin-3 can result in tumor transformation and invasiveness, or confer propensity for tumor cell survival. In addition, galectin-3 was abundantly expressed in cirrhotic liver in peripheral distribution within regenerating nodules. Such galectin-3 expression in rapidly proliferating hepatocytes in cirrhotic liver may be a result of the high mitotic index. Alternatively, it is possible that proliferating cells expressing galectin-3 are in the process of being transformed, thus indicating an early neoplastic event.

Galectin-3 expression is induced in cirrhotic liver and hepatocellular carcinoma

Galectins are a family of beta-galactoside-binding animal lectins. In particular, a widely studied member galectin-3, previously designated as epsilonBP, CBP35, Mac-2, L-29 and L-34, has been associated with assorted processes such as cell growth, tumor transformation and metastasis. Galectin-3 is expressed in various tissues and organs but is significantly absent in normal hepatocytes. However, evaluation of patient liver biopsies for galectin-3 expression resulted in the finding that hepatocellular carcinoma (HCC) frequently expressed significant levels of this lectin (76% immunohistochemically positive). Further investigation revealed that galectin-3 expression in HCC is independent of whether the patient had prior hepatitis B virus infection: 14 of 18 HCC cases from HBV- patients, and 5 of 7 cases from HBV patients demonstrated positive galectin-3 immunohistochemistry. However, co-transfection studies using a galectin-3 promoter construct and an HBV-X protein (HBV-X) expression vector demonstrated that galectin-3 expression can occur through transactivation of the lectin promoter by HBV-X. Based on presently known properties of this lectin, it is possible that deregulated expression of galectin-3 can result in tumor transformation and invasiveness, or confer propensity for tumor cell survival. In addition, galectin-3 was abundantly expressed in cirrhotic liver in peripheral distribution within regenerating nodules. Such galectin-3 expression in rapidly proliferating hepatocytes in cirrhotic liver may be a result of the high mitotic index. Alternatively, it is possible that proliferating cells expressing galectin-3 are in the process of being transformed, thus indicating an early neoplastic event.

Effect of intravenous infusions of 12-O-tetradecanoylphorbol-13-acetate (TPA) in patients with myelocytic leukemia: preliminary studies on therapeutic efficacy and toxicity

Studies by several investigators have shown that 12-0-tetradecanoylphorbol-13-acetate (TPA) is an extraordinarily potent stimulator of differentiation of cultured human promyelocytic leukemia cells in vitro. In the present study, TPA was administered to humans by i.v. infusion without irreversible toxicity, and it was shown to have pharmacological activity for the treatment of myelocytic leukemia in patients refractory to cytosine arabinoside (Ara C), retinoic acid, and other antileukemic drugs. Marked decreases in bone marrow myeloblasts as well as temporary remission of disease symptoms were observed when TPA was administered alone or in combination with vitamin D3 and Ara C. Additional studies with TPA after the determination of optimum dosing regimens are needed to determine whether long-lasting or permanent remissions of myelocytic leukemia can be achieved. Transient and reversible side effects were observed after a 1-mg i.v. dose of TPA, but these adverse effects became less intense or disappeared when a lower dose of TPA was used. The results of this study indicate a therapeutic effect of TPA in patients with myelocytic leukemia.

Role of the carboxyl-terminal lectin domain in self-association of galectin-3

Galectin-3 is a member of a large family of beta-galactoside-binding animal lectins and is composed of a carboxyl-terminal lectin domain connected to an amino-terminal nonlectin part. Previous experimental results suggest that, when bound to multivalent glycoconjugates, galectin-3 self-associates through intermolecular interactions involving the amino-terminal domain. In this study, we obtained evidence suggesting that the protein self-associates in the absence of its saccharide ligands, in a manner that is dependent on the carboxyl-terminal domain. This mode of self-association is inhibitable by the lectin's saccharide ligands. Specifically, recombinant human galectin-3 was found to bind to galectin-3C (the carboxyl-terminal domain fragment) conjugated to Sepharose 4B and the binding was inhibitable by lactose. In addition, biotinylated galectin-3 bound to galectin-3 immobilized on plastic surfaces and the binding could also be inhibited by various saccharide ligands of the lectin. A mutant with a tryptophan to leucine replacement in the carboxyl-terminal domain, which exhibited diminished carbohydrate-binding activity, did not bind to galectin-3C-Sepharose 4B. Furthermore, galectin-3C formed covalent homodimers when it was treated with a chemical cross-linker and the dimer formation was completely inhibited by lactose. Therefore, galectin-3 can self-associate through intermolecular interactions involving both the amino- and the carboxyl-terminal domains and the relative contribution of each depends on whether the lectin is bound to its saccharide ligands.

Self-sustained pH oscillations in a compartmentalized enzyme reactor system

This work represents our continued effort toward fulfilling the need to discover a model system for experimental investigations of temporal oscillations in an enzyme-membrane system. In this paper, the regions in the parameter space where self-sustained pH oscillations can be induced for a compartmentalized enzyme reactor system, which consists of a well-stirred reactor, a reservoir and a membrane containing no enzyme, were determined via numerical simulation with two proteolytic enzymes: papain (EC 3.4.22.2) and alpha-chymotrypsin (EC 3.4.21.1). The sizes of the regions were qualitatively compared with those associated with enzymic membrane system. As a result, we found that the possibility of experimentally observing self-sustained oscillations in the compartmentalized papain reactor system, as well as in the papain-membrane system, is high. However, self-sustained pH oscillations are less likely in the compartmentalized alpha-chymotrypsin reactor system than in the alpha-chymotrypsin-membrane system.

Expression of galectin-3 modulates T-cell growth and apoptosis

Galectin-3 is a member (if a large family of beta-galactoside-binding animal lectins. It has been shown that the expression of galectin-3 is upregulated in proliferating cells, suggesting a possible role for this lectin in regulation of cell growth. Previously, we have shown that T cells infected with human T-cell leukemia virus type I express high levels of galectin-3, in contrast to uninfected cells, which do not express detectable amounts of this protein. In this study, we examined growth properties of human leukemia T cells transfected with galectin-3 cDNA, and thus constitutively overexpressing this lectin. Transfectants expressing galectin-3 displayed higher growth rates than control transfectants, which do not express this lectin. Furthermore, galectin-3 expression in these cells confers resistance to apoptosis induced by anti-Fas antibody and staurosporine. Galectin-3 was found to have significant sequence similarity with Bcl-2, a well-characterized suppressor of apoptosis. In particular, the lectin contains the NWGR motif that is highly conserved among members of the Bcl-2 family and shown to be critical for the apoptosis-suppressing activity. We further demonstrated that galectin-3 interacts with Bc1-2 in a lactose-inhibitable manner. We conclude that galectin-3 is a regulator of cell growth and apoptosis and it may function through a cell death inhibition pathway that involves Bcl-2.

Self-sustained pH oscillations in immobilized proteolytic enzyme systems

This work represents our first step toward fulfilling the need to discover a model system for experimental investigations of temporal oscillations, pattern formations, and other non-linearity related dynamic behavior in immobilized-enzyme-membrane systems. In this paper, the regions in the parameter space where self-sustained pH oscillations can be induced were determined via extensive numerical simulation for five enzyme-membrane systems involving four proteolytic enzymes: alpha-chymotrypsin, trypsin, bromelain, and ficin. From this study, we concluded that, even with current enzyme-immobilization techniques, the possibility of experimentally observing self-sustained pH oscillations in a flat membrane immobilized with alpha-chymotrypsin and using N-acetyl-L-tryptophan ethyl ester as a substrate is high. Under suitable conditions and with extra efforts, self-sustained oscillations may also occur in membrane systems immobilized with ficin, trypsin and bromelain.

Direct determination of phenylalanine in serum extracts of phenylketonuria patients by reversed-phase high-performance liquid chromatography

A method for direct determination of phenylalanine (Phe) in serum extract by reversed-phase high-performance liquid chromatography with an octadecylsilane column has been devised. Phe is monitored at 220 nm with a UV detector. The mobile phase is a mixture of methanol and water (10:90) with added phosphoric acid and potassium dihydrogen phosphate and has a pH value of 4.3. The minimum detectable amount is 6 ng. The average contents of Phe found for healthy adults and children are 12 and 15 micrograms/ml respectively. Phe contents of sera of three phenylketonuria children are about 10 to 15 times higher than these values.