Restoring functional TDP-43 oligomers in ALS and laminopathic cellular models through baicalein-induced reconfiguration of TDP-43 aggregates

A group of misfolded prone-to-aggregate domains in disease-causing proteins has recently been shown to adopt unique conformations that play a role in fundamental biological processes. These processes include the formation of membrane-less sub-organelles, alternative splicing, and gene activation and silencing. The cellular responses are regulated by the conformational switching of prone-to-aggregate domains, independently of changes in RNA or protein expression levels. Given this, targeting the misfolded states of disease-causing proteins to redirect them towards their physiological conformations is emerging as an effective therapeutic strategy for diseases caused by protein misfolding. In our study, we successfully identified baicalein as a potent structure-correcting agent. Our findings demonstrate that baicalein can reconfigure existing TDP-43 aggregates into an oligomeric state both in vitro and in disease cells. This transformation effectively restores the bioactivity of misfolded TDP-43 proteins in cellular models of ALS and premature aging in progeria. Impressively, in progeria cells where defective lamin A interferes with TDP-43-mediated exon skipping, the formation of pathological TDP-43 aggregates is promoted. Baicalein, however, restores the functionality of TDP-43 and mitigates nuclear shape defects in these laminopathic cells. This establishes a connection between lamin A and TDP-43 in the context of aging. Our findings suggest that targeting physiological TDP-43 oligomers could offer a promising therapeutic avenue for treating aging-associated disorders.

Effects of mask-wearing on treadmill exercise test

Background

Concerning about the spread of COVID-19, World Health Organization recommends wearing facemasks to minimize viral transmission. Patients are required to wear facemasks while conducting treadmill exercise tests in hospitals. The effects of mask-wearing on the results of stress exercise testing remain uncertain.

Purpose

This study aims to assess the impact of mask-wearing on the physiological parameters during treadmill exercise testing.

Methods

Patients who underwent treadmill exercise test using the Bruce protocol for the diagnosis of ischemic heart disease were retrospectively examined between 2020 and 2021. A propensity score matching was performed to adjust the baseline characteristics of patients with and without mask. Blood pressure, heart rate, exercise duration, and the interpretation of stress test were compared. The ischemic ST-segment response was defined as flat or downsloping depression of the ST seg-ment >0.1 mV below baseline and lasting longer than 0.08 second. Nondiagnostic result of treadmill exercise test was defined as absence of ischemic ST-segment response in which the 90% of maximal predicted heart rate for age and sex was not achieved.

Results

Following 1:1 propensity score matching, a total of 3,996 patients were enrolled for analysis, including 1,998 patients who performed treadmill exercise testing with masks, and 1,998 without masks. Baseline characteristics were similar between the two groups (mean age, 56.1±12.1 years; 38.7% female; mean body mass index, 25.5±3.9 kg/m²). At baseline, patients with masks had significantly higher heart rate (84.8±14.7 bpm vs. 82.5±14.0 bpm; p<0.001) and lower systolic blood pressure (130.4±19.0 mmHg vs. 132.4±18.7 mmHg; p=0.001) than those without masks. Patients with masks conducted significantly shorter duration of exercise (435±128 seconds vs. 481±133 seconds; p<0.001), achieved significantly lower measurement of peak heart rate (149.5±17.1 bpm vs. 152.7±17.0 bpm; p<0.001), and had significantly lower rate-pressure products (26,366±5,207 mmHg·bpm vs. 27,629±5,242 mmHg*bpm; p<0.001) than those without masks. The proportion of patients who were unable to complete stage II of the Bruce protocol was significantly higher among patients with masks (15.1% vs. 9.0%; p<0.001). The proportion of nondiagnostic result was significantly higher among patients with mask (12.2% vs. 8.8%; p<0.001), whereas the proportion of positive ischemic ST-segment response rate was significantly higher among patients without mask (28.1% vs. 23.3%; p=0.001).

Conclusions

Our study demonstrated that performing treadmill exercise test with mask could significantly decrease the duration of exercise, reduce the maximal achieved heart rate, decease the rate-pressure product, and thus reduce the diagnostic power of treadmill exercise testing.

Funding Acknowledgement

Type of funding sources: None.

CD28 engagement inhibits CD73-mediated regulatory activity of CD8+ T cells

CD28 is required for T cell activation as well as the generation of CD4⁺Foxp3⁺ Treg. It is unclear, however, how CD28 costimulation affects the development of CD8⁺ T cell suppressive function. Here, by use of Hepa1.6.gp33 in vitro killing assay and B16.gp33 tumor mouse model we demonstrate that CD28 engagement during TCR ligation prevents CD8⁺ T cells from becoming suppressive. Interestingly, our results showed that ectonucleotidase CD73 expression on CD8⁺ T cells is upregulated in the absence of CD28 costimulation. In both murine and human tumor-bearing hosts, CD73 is upregulated on CD28^-CD8⁺ T cells that infiltrate the solid tumor. UPLC-MS/MS analysis revealed that CD8⁺ T cells activation without CD28 costimulation produces elevated levels of adenosine and that CD73 mediates its production. Adenosine receptor antagonists block CD73-mediated suppression. Our data support the notion that CD28 costimulation inhibits CD73 upregulation and thereby prevents CD8⁺ T cells from becoming suppressive. This study uncovers a previously unidentified role for CD28 costimulation in CD8⁺ T cell activation and suggests that the CD28 costimulatory pathway can be a potential target for cancer immunotherapy.

Long-term evaluation of activated carbon as an adsorbent for biogas desulfurization

In this study, granular activated carbon (GAC) was used as an adsorbent for biogas desulfurization. Biogas containing 932-2,350 ppm of H₂S was collected from an anaerobic digester to treat the wastewater from a dairy farm with about 200 cows. An adsorption test was performed by introducing the biogas to a column that was packed with approximately 50 L of commercial GAC. The operation ceased if the effluent gas had an H₂S concentration of over 100 ppm. The GAC was replaced by a given weight of new GAC in a subsequent test. According to the results, for H₂S concentrations in the range of 932-1,560 ppm (average±SD = 1,260 ± 256 ppm), 1 kg of the GAC yielded biogas treatment capacities of 568 ± 112 m³ and H₂S adsorption capacities of 979 ± 235 g. For the higher influent H₂S concentrations of 2,110 ± 219 ppm, the biogas treatment and H₂S-adsorption capacities decreased to 229 ± 18 m³ and 668 ± 47 g, respectively. An estimation indicated a requisite cost of US$16.5 for the purification of 1,000 m³ of biogas containing 2,110 ppm of H₂S. This cost is approximately 5% of US$330, the value of 1,000 m³ of biogas.

IMPLICATIONS

Biogas generated from anaerobic digesters of animal manure and municipal wastewater sludge contains hydrogen sulfide which must be removed before it can be combusted in electricity-generation engines. This study demonstrated that commercial activated carbon adsorption can be an economical and effective approach for removing hydrogen sulfide from biogas. In this study, granular activated carbon (GAC) was used as an adsorbent for biogas desulfurization. The biogas containing 932-2,350 ppm of H₂S was collected from an anaerobic digester for treating wastewater collected from a 200 dairy farm. The adsorption test was performed by introducing the biogas to a PVC column packed with a commercial GAC of around 50 L. Operation ceased if the effluent gas had an H₂S concentration of over 100 ppm. A given weight of the new GAC was replaced for a successive test.

Abstract BS1-2: Genome regulation by long noncoding RNA genes

The discovery of extensive transcription of long noncoding RNAs (lncRNAs) provide an important new perspective on the centrality of RNA in gene regulation. I will discuss genome-scale strategies to discover and characterize lncRNAs, including RNA chemical modifications and RNA structures. LncRNAs form extensive networks of ribonucleoprotein (RNP) complexes with numerous chromatin regulators, and target these enzymatic activities to appropriate locations in the genome. Long noncoding RNAs can function as modular scaffolds to specify higher order organization in RNP complexes and in chromatin states. A new emerging theme is that DNA elements that mediate lncRNA expression can also have powerful effects in controlling chromatin neighborhoods, which alter oncogene expression and activity. The importance of these modes of regulation is underscored by the newly recognized roles of long RNAs in human diseases.

Citation Format: HY Chang. Genome regulation by long noncoding RNA genes [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr BS1-2.

Energy intake at different times of the day: Its association with elevated total and LDL cholesterol levels

BACKGROUND AND AIMS

This study examined the association between macronutrient intake at different times of the day and blood lipid levels.

METHODS AND RESULTS

The study was based on the Nutrition and Health Survey in Taiwan, a cross-sectional study of non-institutionalized and non-pregnant healthy adults (≥19-years-old). A one-day (24 h) dietary recall assessed participants' food intake. Fasting plasma triglycerides, total cholesterol, and high-density lipoprotein (HDL) cholesterol were determined. Low-density lipoprotein (LDL) cholesterol was estimated based on the Friedewald formula. According to the data of eligible subjects (n = 1283), the time of energy intake was categorized into three meal times 0500-0929 (morning), 1130-1329 (noon), and 1730-2029 (evening), along with three snack times 0930-1129 (mid-morning), 1330-1729 (afternoon), and 2030-0459 (night). Energy and macronutrient intake were calculated for the 6 time periods, based on 24 h recall data. An adjusted regression model showed that by transferring 100 kcal intake at night to the morning or noon, LDL cholesterol would be lower by 1.46 (95% CI: 2.42-0.50) and 1.27 mg/dL (95% CI: 2.24-0.30), respectively. Transferring 100 kcal of fat intake at night to earlier periods was associated with a lower LDL cholesterol level, especially transferring to noontime (significantly lower by 5.21 mg/dL, 95% CI: [7.42-2.99]) and evening (significantly lower by 3.19 mg/dL, 95% CI: [6.29-0.08]).

CONCLUSIONS

Total cholesterol and LDL cholesterol had the same pattern of association with the timing of energy intake. The study showed that elevated total and LDL cholesterol were positively associated with nighttime energy and fat intake.

Overexpression of miR-101-2 in donor cells improves the early development of Holstein cow somatic cell nuclear transfer embryos

Accumulating studies have suggested that microRNA play a part in regulating multiple cellular processes, such as cell proliferation, apoptosis, the cell cycle, and embryo development. This study explored the effects of miR-101-2 on donor cell physiological status and the development of Holstein cow somatic cell nuclear transfer (SCNT) embryos in vitro. Holstein cow bovine fetal fibroblasts (BFF) overexpressing miR-101-2 were used as donor cells to perform SCNT; then, cleavage rate, blastocyst rate, inner cell mass-to-trophectoderm ratio, and the expression of some development- and apoptosis-related genes in different groups were analyzed. The miR-101-2 suppressed the expression of inhibitor of growth protein 3 (ING3) at mRNA and protein levels, expedited cell proliferation, and decreased apoptosis in BFF, suggesting that ING3, a target gene of miR-101-2, is a potential player in this process. Moreover, by utilizing donor cells overexpressing miR-101-2, the development of bovine SCNT embryos in vitro was significantly enhanced; the apoptotic rate in SCNT blastocysts was reduced, and the inner cell mass-to-trophectoderm ratio and SOX2, POU5F1, and BCL2L1 expression significantly increased, whereas BAX and ING3 expression decreased. Collectively, these findings suggest that miR-101-2 promotes BFF proliferation and vitality, reduces their apoptosis, and improves the early development of SCNT embryos.

A Point-based Mortality Prediction System for Older Adults with Diabetes

The mortality prediction models for the general diabetic population have been well established, but the corresponding elderly-specific model is still lacking. This study aims to develop a mortality prediction model for the elderly with diabetes. The data used for model establishment were derived from the nationwide adult health screening program in Taiwan in 2007-2010, from which we applied a 10-fold cross-validation method for model construction and internal validation. The external validation was tested on the MJ health screening database collected in 2004-2007. Multivariable Cox proportional hazards models were used to predict five-year mortality for diabetic patients ≥65 years. A total of 220,832 older subjects with diabetes were selected for model construction, of whom 23,241 (10.5%) died by the end of follow-up (December 31, 2011). The significant predictors retained in the final model included age, gender, smoking status, body mass index (BMI), fasting glucose, systolic and diastolic blood pressure, leukocyte count, liver and renal function, total cholesterol, hemoglobin, albumin, and uric acid. The Harrell's C in the development, internal-, and external-validation datasets were 0.737, 0.746, and 0.685, respectively. We established an easy-to-use point-based model that could accurately predict five-year mortality risk in older adults with diabetes.

Interpenetration of CH3NH3PbI3 and TiO2 improves perovskite solar cells while TiO2 expansion leads to degradation

Perovskite solar cells have drawn much attention and achieved efficiencies over 22%, but relatively little is known about the long-term stability under photovoltaic operation. So far, stability studies have reported about the importance of degradation of each layer, but little to no consideration has been given to the whole device architecture. We investigated the stability of perovskite solar cells in order to fundamentally understand the mechanism behind efficiency improvement/degradation during device operation. We found that during operation the interfaces of the perovskite and the electron-transport layer (ETL), meso-porous TiO₂, further intermix with each other, which leads to improved power conversion efficiency (PCE) during the initial operation of these solar cells. The operation-induced structural changes are examined directly by X-ray photoelectron spectroscopy (XPS) with in situ low-energy Ar⁺ sputtering and time-of-flight secondary ion mass spectrometry (ToF-SIMS) with C₆₀ sputtering. In addition, this study describes that the primary cause of irreversible degradation during operation is due to the expansion of TiO₂ and ion migration throughout the perovskite solar cell.

The effect of ligand–ligand interactions on the formation of photoluminescent gold nanoclusters embedded in Au(i)–thiolate supramolecules

Photoluminescence of cysteine-capped gold nanoclusters obtained via the reduction of –[Cys–Au(i)]_n– supramolecules is highly dependent on the degree of supramolecular aggregation.

Has Choosing Wisely® affected rates of dual-energy X-ray absorptiometry use?

Reducing overuse of tests such as dual-energy X-ray absorptiometry (DXA) scans in younger women is an important quality issue. We evaluated trends in DXA ordering before and after Choosing Wisely recommendations were released. We found no significant difference in ordering trends suggesting that other initiatives are needed to change behavior.

INTRODUCTION

Reducing overuse of tests such as dual-energy X-ray absorptiometry (DXA) scans in younger women is an important quality issue, but trends in care are difficult to change. We evaluated (1) trends in DXA ordering before and after the Choosing Wisely recommendation release and (2) patterns of key characteristics that indicate a potentially appropriate DXA scan order.

METHODS

We performed a retrospective longitudinal analysis of electronic health record data at a multi-specialty, ambulatory care network of 34 practices across Maryland and Washington, DC. Since the Choosing Wisely DXA recommendation was released April 2012, the study periods were April-December 2011 (pre-initiative) and April-December 2012 (post-initiative). Women between 50 and 64 years with primary care encounters, and primary care providers who saw ten or more women in the study population in both pre and post periods were included.

RESULTS

For 42,320 eligible patients, the mean provider ordering rate was 2.6 % pre-initiative and 2.0 % post-initiative; there was no significant difference in trend over time. Over 70 % of the population had no characteristics associated with potentially appropriate DXA ordering. Low body mass index, current smoker status, and osteopenia were the most common characteristics indicating potentially appropriate DXA orders. Patients with any of these three characteristics had DXA ordering rates between 3-20 %.

CONCLUSIONS

The trend in provider ordering rates of DXA scans did not decrease after the release of the DXA Choosing Wisely recommendation. Targeted initiatives addressing providers with high ordering rates will be needed to change behavior.

Seasonal distribution of potentially pathogenic Acanthamoeba species from drinking water reservoirs in Taiwan

In order to detect the presence/absence of Acanthamoeba along with geographical variations, water quality variations and seasonal change of Acanthamoeba in Taiwan was investigated by 18S ribosomal RNA (rRNA) gene TaqMan quantitative real-time PCR. Samples were collected quarterly at 19 drinking water reservoir sites from November 2012 to August 2013. Acanthamoeba was detected in 39.5 % (30/76) of the water sample, and the detection rate was 63.2 % (12/19) from samples collected in autumn. The average concentration of Acanthamoeba was 3.59 × 10(4) copies/L. For geographic distribution, the detection rate for Acanthamoeba at the northern region was higher than the central and southern regions in all seasons. Results of Spearman rank test revealed that heterotrophic plate count (HPC) had a negative correlation (R = -0.502), while dissolved oxygen (DO) had a positive correlation (R = 0.463) in summer. Significant differences were found only between the presence/absence of Acanthamoeba and HPC in summer (Mann-Whitney U test, P < 0.05). T2 and T4 genotypes of Acanthamoeba were identified, and T4 was the most commonly identified Acanthamoeba genotypes. The presence of Acanthamoeba in reservoirs presented a potential public health threat and should be further examined.

Effects of high thoracic epidural anesthesia on ischemic cardiomyopathy cardiac function and autonomic neural function

We aimed at observing the effects of high thoracic epidural anesthesia (HTEA) on cardiac structure and function, heart rate variability (HRV), and QT interval variation (QTV) in ischemic cardiomyopathy (ICM) patients with chronic heart failure. We divided 30 ICM patients into HTEA (N = 16) and control (N = 14) groups.The control group was treated with medication, and the HTEA group was treated with HTEA and medication for 4 weeks. We measured the changes in the left-ventricular end-diastolic diameter (LVEDd) and left-ventricular ejection fraction (LVEF) before and after treatment by using echocardiography and examined changes in HRV and QTV using ambulatory electrocardiogram. HTEA significantly narrowed the LVEDd, improved LVEF, significantly increased the HRV, and significantly reduced the QTV in the ICM group compared to the control group. HTEA significantly narrowed the ventricular chamber diameter size of ICM patients, enhanced myocardial contractility, increased myocardial electrical stability, and improved the cardiac structure and function.

Heat-shock protein dysregulation is associated with functional and pathological TDP-43 aggregation

Conformational disorders are involved in various neurodegenerative diseases. Reactive oxygen species (ROS) are the major contributors to neurodegenerative disease; however, ROS that affect the structural changes in misfolded disease proteins have yet to be well characterized. Here we demonstrate that the intrinsic propensity of TDP-43 to aggregate drives the assembly of TDP-43-positive stress granules and soluble toxic TDP-43 oligomers in response to a ROS insult via a disulfide crosslinking-independent mechanism. Notably, ROS-induced TDP-43 protein assembly correlates with the dynamics of certain TDP-43-associated chaperones. The heat-shock protein (HSP)-90 inhibitor 17-AAG prevents ROS-induced TDP-43 aggregation, alters the type of TDP-43 multimers and reduces the severity of pathological TDP-43 inclusions. In summary, our study suggests that a common mechanism could be involved in the pathogenesis of conformational diseases that result from HSP dysregulation.

Synthesis and antimicrobial activity of gold/silver-tellurium nanostructures

Gold-tellurium nanostructures (Au-Te NSs), silver-tellurium nanostructures (Ag-Te NSs), and gold/silver-tellurium nanostructures (Au/Ag-Te NSs) have been prepared through galvanic reactions of tellurium nanotubes (Te NTs) with Au(3+), Ag(+), and both ions, respectively. Unlike the use of less environmentally friendly hydrazine, fructose as a reducing agent has been used to prepare Te NTs from TeO2 powders under alkaline conditions. The Au/Ag-Te NSs have highly catlaytic activity to convert nonfluorescent Amplex Red to form fluorescent product, revealing their great strength of generating reactive oxygen species (ROS). Au/Ag-Te NSs relative to the other two NSs exhibit greater antimicrobial activity toward the growth of E. coli, S. enteritidis, and S. aureus; the minimal inhibitory concentration (MIC) values of Au/Ag-Te NSs were much lower (>10-fold) than that of Ag-Te NSs and Au-Te NSs. The antibacterial activity of Au/Ag-Te NSs is mainly due to the release of Ag(+) ions and Te-related ions and also may be due to the generated ROS which destroys the bacteria membrane. In vitro cytotoxicity and hemolysis analyses have revealed their low toxicity in selected human cell lines and insignificant hemolysis in red blood cells. In addition, inhibition zone measurements using a Au/Ag-Te NSs-loaded konjac jelly film have suggested that it has great potential in practial application such as wound dressing for reducing bacterial wound infection. Having great antibacterial activitiy and excellent biocompatibility, the low-cost Au/Ag-Te NSs hold great potential as effective antimicrobial drugs.

Association between serum ferritin and microalbuminuria in Type 2 diabetes in Taiwan

AIMS

Serum ferritin has been found closely related with diabetes and glucose metabolism, but its impact on diabetic nephropathy remains unknown. This study aimed to explore the association between serum ferritin and microalbuminuria in Type 2 diabetes.

METHODS

Eight hundred and fifty-one subjects with Type 2 diabetes were selected from a cohort participating in a glycaemic control study in Taiwan in 2008. We used urine albumin:creatinine ratio to define microalbuminuria; serum ferritin was divided into quartiles for analysis. Logistic regression and trend tests were used to delineate the association between serum ferritin and microalbuminuria.

RESULTS

Subjects with diabetes with higher ferritin tended to have more metabolic disorders, higher high-sensitivity C-reactive protein and higher prevalence of microalbuminuria. Compared with those in the lowest quartile, subjects with diabetes in the highest ferritin quartile were 55% (P = 0.029) more likely to have microalbuminuria. After controlling for demographics, metabolic profiles and other inflammatory markers, the association between serum ferritin levels and microalbuminuria remained significant (P for trend < 0.001). This independent relationship was not changed either for those who had better glycaemic control or those who had not used an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker.

CONCLUSIONS

The current study shows hyperferritinemia may be an independent risk factor of nephropathy in patients with Type 2 diabetes.

Reproductive biology of female bigeye tuna Thunnus obesus in the western Pacific Ocean

The reproductive biology of female bigeye tuna Thunnus obesus was assessed by examining 888 fish (ranging from 84·9 to 174·4 cm fork length, LF ) caught by Taiwanese offshore longliners in the western Pacific Ocean from November 1997 to November 1998 and November to December 1999 and 258 gonad samples from these fish. The overall sex ratio of the catch during the sampling differed significantly from 0·5, but males were predominant in sizes >140 cm LF . Reproductive activity (assessed by histology), a gonado-somatic index, and the size-frequency distributions of whole oocytes indicated that spawning occurred throughout the year and the major spawning season appeared to be from February to September. The estimated sizes at 50% maturity (LF50 ) of females was 102·85 cm (95% c.i.: 90·79-110·21 cm) and the smallest mature female was 99·7 cm LF . They are multiple spawners and oocytes develop asynchronously. The proportion of mature (0·63) and reproductively active (0·70) females with ovaries containing postovulatory follicles indicated that they spawn almost daily. Batch fecundity for 15 females with the most advanced oocytes (>730 µm) ranged from 0·84 to 8·56 million eggs (mean ± s.d. = 3·06 ± 2·09). The relationships between batch fecundity (FB , in millions of eggs) and LF (cm) and round mass (MR , kg) were FB=9·91×10-14LF6·38 (r(2)  = 0·84) and FB=8·89×10-4MR2·05 (r(2)  = 0·80), respectively. The parameters estimated in this study are key information for stock assessments of T. obesus in the western Pacific Ocean and will contribute to the conservation and sustainable yield of this species.

Nucleotide mismatches of foot-and-mouth disease virus during replication

As there is a lack of error correction mechanisms during RNA replication, foot-and-mouth disease virus (FMDV) has a very high mismatch rate, which leads to a high mutation rate, in the range of 10(-3) to 10(-5) per nucleotide site per genome replication. We examined the nucleotide mismatch of FMDV during replication, based on the whole genomes of the 7 serotypes retrieved from NCBI. With the Mega bio-software, SPSS, and Microsoft Excel, we studied the nucleotide differences compared to the sequence in the RefSeq database, and developed two probable mutation models, i.e., once mutation model and complication mutation model. Further analysis on the nucleotide mismatch during replication was made. We found that FMDV share similar difference rates between nucleotide and reverse differences, for example the mutation U→C and C→U. We also found that each nucleotide has its domain mismatch, and the virus kept a constant nucleotide composition during mutations.

HbA1c variability is associated with microalbuminuria development in type 2 diabetes: a 7-year prospective cohort study

AIMS/HYPOTHESIS

HbA(1c) variability has been shown to be an independent risk factor for nephropathy in patients with type 1 diabetes. In this study, we aimed to explore the association between HbA(1c) variability and microalbuminuria development in patients with type 2 diabetes. We also intended to test the applicability of serially measured HbA(1c) over 2 years for this risk assessment.

METHODS

Between 2003 and 2005, we recruited 821 middle-aged normoalbuminuric individuals with type 2 diabetes and followed them through to the end of 2010. The average follow-up time was 6.2 years. We defined microalbuminuria as a urine albumin to creatinine ratio of 30 mg/g (3.4 mg/mmol) or higher. HbA(1c) variability was calculated by the SD of serially measured HbA(1c). The Cox proportional hazards model was used to evaluate the association between HbA(1c) SD quartile and development of microalbuminuria.

RESULTS

The incidence of microalbuminuria for the overall population was 58.4, 58.6, 60.8 and 91.9 per 1,000 person-years for Q1- to Q4-adjusted HbA(1c) SD, respectively (p for trend = 0.042). Compared with patients in Q1, those in Q4 were about 37% more likely to develop microalbuminuria. The HR derived from a series of 2 year HbA(1c) measurements was similar to that from data collection for longer than 4 years.

CONCLUSIONS/INTERPRETATION

In addition to mean HbA(1c) values, HbA(1c) variability, even measured as early as 2 years, is independently associated with the development of microalbuminuria in patients with type 2 diabetes.

Detection of mercury ions based on mercury-induced switching of enzyme-like activity of platinum/gold nanoparticles

In this study, bimetallic platinum/gold nanoparticles (Pt/Au NPs) were found to exhibit peroxidase-like activity, and the deposition of mercury was found to switch the enzymatic activity to a catalase-like activity. Based on this phenomenon, we developed a new method for detecting mercury ions through their deposition on bimetallic Pt/Au NPs to switch the catalytic activity of Pt/Au NPs. Pt/Au NPs could be easily prepared through reduction of Au(3+) and Pt(4+) by sodium citrate in a one-pot synthesis. The peroxidase catalytic activity of the Pt/Au NPs was controlled by varying the ratios of Pt to Au. The Pt(0.1)/Au NPs (prepared with a [Au(3+)]/[Pt(4+)] molar ratio of 9.0/1.0) showed excellent oxidation catalysis for H(2)O(2)-mediated oxidation of Amplex® Red (AR) to resorufin. The oxidized product of AR, resorufin, fluoresces more strongly (excitation/emission wavelength maxima ca. 570/585 nm) than AR alone. The peroxidase catalytic activity of Pt(0.1)/Au NPs was switched to catalase-like activity in the presence of mercury ions in a 5.0 mM tris(hydroxymethyl)aminomethane (Tris)-borate solution (pH 7.0) through the deposition of Hg on the particle surfaces owing to the strong Hg-Au metallic bond. The catalytic activity of Hg-Pt(0.1)/Au NPs is superior (by at least 5-fold) to that of natural catalase (from bovine liver). Under optimal solution conditions [5.0 mM Tris-borate (pH 7.0), H(2)O(2) (50 mM), and AR (10 μM)] and in the presence of the masking agents polyacrylic acid and tellurium nanowires, the Pt(0.1)/Au NPs allowed the selective detection of inorganic mercury (Hg(2+)) and methylmercury ions (MeHg(+)) at concentrations as low as several nanomolar. This simple, fast, and cost-effective system enabled selective determination of the spiked concentrations of Hg(2+) and MeHg(+) in tap, pond, and stream waters.

Ipr1 gene mediates RAW 264.7 macrophage cell line resistance to Mycobacterium bovis

Tuberculosis caused by Mycobacterium bovis (M. bovis) seriously affects efficiency of animal production with impacts on public health as well. Effective programmes of prevention and eradication of M. bovis infection therefore are urgently needed. Intracellular pathogen resistance gene 1 (Ipr1) is well known to mediate innate immunity to Mycobacterium tuberculosis (MTB), but there are no reports as to whether Ipr1 can enhance the phagocytic ability of macrophage against M. bovis. In this investigation, RAW 264.7 macrophage was transduced with lentiviral vector carrying Ipr1 (named Lenti-Ipr1); transgenic cells were identified by RT-PCR and western blotting. Transgenic positive cells (R-Ipr1) were then infected with an M. bovis virulent strain, with non-transduced cells used as control. When cell proliferation, viability and apoptosis of the two groups were investigated, it was found that infected RAW 264.7 died by necrosis whereas R-Ipr1 underwent apoptosis. Furthermore, the numbers of intracellular bacteria in R-Ipr1 were lower than those in control cells (P < 0.05). To identify the role of Ipr1, we measured the genes of Casp3, Mcl-1 and NOS2A which associated with macrophage activation and apoptosis by real-time quantitative PCR. The results demonstrated that Ipr1 gene expression can enhance anti-M. bovis infection of macrophage. This establishes a basis for the future production of Ipr1-transgenic cattle to strengthen the tuberculosis resistance.

A retrospective study of pulmonary infarction in patients with systemic lupus erythematosus from southern Taiwan

Since large-scale reports of pulmonary infarction in systemic lupus erythematosus (SLE) are limited, a retrospective study was performed for this manifestation in 773 hospitalized patients in southern Taiwan from 1999 to 2009. Pulmonary infarction was defined as the presence of pulmonary embolism, persistent pulmonary infiltrates, and characteristic clinical symptoms. Demographic, clinical, laboratory, and radiological images data were analyzed. There were 12 patients with pulmonary embolism and 9 of them had antiphospholipid syndrome (APS). Six patients (19 to 53 years, average 38.2 ± 12.6) with 9 episodes of lung infarction were identified. All cases were APS and four episodes had coincidental venous thromboembolism. There were four episodes of bilateral infarction and seven episodes of larger central pulmonary artery embolism. Heparin therapy was routinely prescribed and thrombolytic agents were added in two episodes. Successful recovery was noted in all patients. In conclusion, there was a 0.8% incidence of pulmonary infarction in patients with SLE, all with the risk factor of APS. Differentiation between pulmonary infarction and pneumonia in lupus patients should be made; they have similar chest radiography with lung consolidation but require a different clinical approach in management. Although this report is a retrospective study with relatively small numbers of lupus patients with lung infarcts, our observation might provide beneficial information on the clinical features and radiological presentations during the disease evolution of pulmonary infarction in SLE with APS.

Diosgenin suppresses hepatocyte growth factor (HGF)-induced epithelial-mesenchymal transition by down-regulation of Mdm2 and vimentin

Substantial activation of the hepatocyte growth factor (HGF)/c-Met pathway leads to cancer cell scattering and invasion and has been observed in several types of cancers, including prostate and colorectal cancers. The phosphorylation cascade downstream of HGF, particularly PI3K/Akt signaling, regulates epithelial-to-mesenchymal transition (EMT). How this signaling governs EMT and whether specific kinases respond to particular EMT effectors remain unclear. This study found specific increases in Mdm2 and vimentin rather than the coregulation of an array of EMT marker proteins in response to HGF-induced EMT in DU145 prostate cancer cells. Importantly, it was further found that diosgenin abrogated HGF-induced DU145 cell scattering and invasion. Moreover, diosgenin effectively inhibited the HGF-induced increases in Mdm2 and vimentin by down-regulating phosphorylated Akt and mTOR. In summary, the results suggest that diosgenin may be a potential compound for use in prostate cancer therapy to target the major HGF-induced EMT pathway.

Abstract P4-01-03: The Homeobox Protein H0XC10 Is Overexpressed in Breast Cancer and Confers Resistance to Chemotherapy

Background: Breast cancer is the second leading cause of cancer deaths in women worldwide. Although chemotherapy is effective, resistance to drugs develops over time and can account for treatment failure in over 90% of metastatic breast cancer patients. HOX genes are homeobox-containing transcription factors well-known for their role in morphogenesis. However, accumulating evidence has emphasized their importance during carcinogenesis and metastasis. The goal of this study is to understand the role of HOXC10 in breast cancer and the consequence of its overexpression in conferring chemotherapy resistance.

Methods: We conducted a tiling array of all four HOX clusters to identify dysregulated HOX genes in a panel of primary and metastatic breast cancer tissues, and validated the overexpression of HOXC10 in metastatic breast cancer. Next we established cell lines that stably overexpress HOXC10 and others where endogenously overexpressed HOXC10 was silenced by shRNAs, and determined phenotypic and biochemical changes resulting from these manipulations.

Results: HOXC10 is overexpressed in 67% of primary breast tumors (n=31), in 82% of the metastatic tissues (n=49) and in most breast cancer cell lines. When compared to cancers at other sites, overexpression tends to be significantly higher in breast cancer, and correlates with increasing grade and tumor size. Cell survival assays (MTT and colony formation) after drug treatment show that overexpression of exogenous HOXC10 in MCF10A conferred drug resistance. Further molecular examination revealed that overexpression of HOXC10 led to a dysregulation in the Rb-E2F pathway, and therefore the G1/S checkpoint was affected. In addition, the tendency for the formation of 8N cells and the concomitant protection from apoptosis suggested that HOXC10 overexpression might lead to genomic endoreduplication and instability. This fact along with the strikingenhanced recovery of the cells from pactitaxel treatment (as compared to the recovery from any other chemotherapeutic drug) and the protection from mitotic catastrophe implied a role of HOXC10 in the mitotic checkpoint. This was confirmed by a dysregulation of the expression of the genes involved in this checkpoint. All these experiments were further validated by stably expressing a shRNA to HOXC10 in SUM159 breast cancer cells with high endogenous HOXC10 levels. Conclusion: Our studies show for the first time that HOXC10, a homeobox protein previously shown to be regulated during the cell cycle and to have a positive effect on proliferation, is overexpressed in the majority of breast cancers. This upregulation may have some clinical implications since cells with higher expression of HOXC10 tend to have more invasive properties, more genomic instability, and are more resistant to some chemotherapy drugs.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-01-03.

Fatal crash trends for Australian young drivers 1997-2007: geographic and socioeconomic differentials

BACKGROUND

Little has been published on changes in young driver fatality rates over time. This paper examines differences in Australian young driver fatality rates over the last decade, examining important risk factors including place of residence and socioeconomic status (SES).

METHODS

Young driver (17-25years) police-recorded passenger vehicle crashes were extracted from New South Wales State records from 1997-2007. Rurality of residence and SES were classified into three levels based on drivers' residential postcode: urban, regional, or rural; and high, moderate, or low SES areas. Geographic and SES disparities in trends of fatality rates were examined by the generalized linear model. Chi-square trend test was used to examine the distributions of posted speed limits, drinking driving, fatigue, seatbelt use, vehicle age, night-time driving, and the time from crash to death across rurality and socioeconomic status.

RESULTS

Young driver fatality rate significantly decreased 5% per year (p<0.05); however, stratified analyses (by rurality and by SES) showed that only the reduction among urban drivers was significant (average 5% decrease per year, p<0.01). The higher relative risk of fatality for rural versus urban drivers, and for drivers of low versus high SES remained unchanged over the last decade. High posted speed limits, fatigue, drink driving and seatbelt non-use were significantly associated with rural fatalities, whereas high posted speed limit, fatigue, and driving an older vehicle were significantly related to low SES fatality.

CONCLUSION

The constant geographic and SES disparities in young driver fatality rates highlight safety inequities for those living in rural areas and those of low SES. Better targeted interventions are needed, including attention to behavioral risk factors and vehicle age.

Road crash trends for young drivers in New South Wales, Australia, from 1997 to 2007

OBJECTIVES

The objective of this article was to explore overall crash and injury trends over the past decade for young drivers residing in New South Wales (NSW), Australia, including gender and age disparities.

METHODS

Passenger vehicle crashes for drivers aged 17-25 occurring during 1997-2007 were extracted from the state crash database to calculate crash rates (per licensed driver). Generalized linear models were used to examine crash trends over time by severity of driver injury, adjusting for age, gender, rurality of residence, and socioeconomic status. Yearly adjusted relative risks of crash by gender and by age group were also examined over the study period.

RESULTS

Young driver noninjury and fatality rates significantly decreased by an average of 4 percent (95% CI: 4-5) and 5 percent (95% CI: 0-9) respectively each year from 1997 to 2007. Young driver injury rates significantly increased by about 12 percent (95% CI: 9-14) to the year 2001 and then significantly decreased. The relative risk of crash (regardless of driver injury) for males compared to females significantly decreased over time. Compared to drivers aged 21-25, drivers aged 17 and particularly 18- to 20-year-olds had significantly and consistently higher crash risks across the study period.

CONCLUSIONS

Overall, there has been a significant decline in young driver crashes in NSW over the last decade. Regardless of injury severity, males' risk of crash has reduced more than female young drivers, but drivers aged 17 continue to be at higher risk. These findings provide feedback on potential road safety successes and areas needing specific interventions for future improvements.

Health-related quality of life predicts hospital admission within 1 year in people with diabetes: a nationwide study from Taiwan

AIMS

To investigate whether health-related quality of life (HRQOL) predicts hospital admission in a nationally representative sample of adults with diabetes.

METHODS

We conducted a prospective study on persons aged > or = 18 years with self-reported physician-diagnosed diabetes (n = 797) who participated in the National Health Interview Survey in Taiwan, 2001. Of these potential participants, 674 provided consent for data linkage and were successfully linked to the National Health Insurance claims data. We analysed the associations between the Short Form 36 (SF-36) subscales and summaries and the occurrence of hospital admission for any cause during 2002.

RESULTS

Approximately 23% of participants with diabetes had at least one hospital admission during 2002. After adjusting for demographic characteristics, co-morbidities and diabetics-related attributes, those who had been admitted to hospital had significantly poorer mean scores on each of the physical dimensions, physical components summary (PCS) and social functioning domain of the SF-36 at baseline. In logistic regression models, poorer scores on the PCS [odds ratio (OR) = 1.80; 95% confidence interval (CI) = (1.14-2.86)], duration of diabetes > or = 10 years [OR = 2.10; 95% CI = (1.14-3.89)] and the presence of heart disease [OR = 1.63; 95% CI = (1.01-2.63)] were significantly associated with an increased risk of hospital admission.

CONCLUSION

In people with diabetes, poorer scores on the PCS of the SF-36 at baseline may provide additional information for assessment of hospital admission risk, independent of other measures of health outcomes.

A simplified tumour model established via Epstein-Barr virus-encoded, nasopharyngeal carcinoma-derived oncogene latent membrane protein 1 in immunocompetent mice

The expression and immune modulation of Epstein-Barr virus-encoded oncogene latent membrane protein 1 (N-LMP1) is essential in the pathogenesis of nasopharyngeal carcinoma. In previous studies, cell transformation has been induced by the expression of EBV-encoded N-LMP1 in non-tumour BALB/c-3T3 cells and these cells have then been used to form tumours in T-cell-deficient nude mice. However, studies using this model have been limited by the lack of a competent immune system. To facilitate the study of immune components in N-LMP1-driven oncogenesis, we herein developed a simplified N-LMP1-derived tumour model in immunocompetent mice. Cell transformation was induced by the expression of N-LMP1 in BALB/c-3T3 cells, and these transformants were used to induce oncogenesis in BALB/c mice. In contrast to the 100% successful tumour-induction rate in nude mice treated with monodispersed transformed cells, the tumour incidence in BALB/c mice was only 5-36%. However, the transplantation of tumour fragments into BALB/c mice yielded a reproducible tumour-induction rate of >85%, which is acceptable for most of the research needs. This novel model of N-LMP1-directed oncogenesis in an immunocompetent environment may serve as an important platform for the future assessment of N-LMP1-targeted tumour therapies.

User adaptive handwriting recognition by self-growing probabilistic decision-based neural networks

It is generally agreed that, for a given handwriting recognition task, a user dependent system usually outperforms a user independent system, as long as a sufficient amount of training data is available. When the amount of user training data is limited, however, such a performance gain is not guaranteed. One way to improve the performance is to make use of existing knowledge, contained in a rich multiuser data base, so that a minimum amount of training data is sufficient to initialize a model for the new user.We mainly address the user adaption issues for a handwriting recognition system. Based on self-growing probabilistic decision-based neural networks (SPDNNs), user adaptation of the parameters of SPDNN is formulated as incremental reinforced and antireinforced learning procedures, which are easily integrated into the batched training procedures of the SPDNN. In this study, we developed 1) an SPDNN based handwriting recognition system; 2) a two-stage recognition structure; and 3) a three-phase training methodology for a) a global coarse classifier (stage 1); b) a user independent hand written character recognizer (stage 2); and c) a user adaptation module on a personal computer. With training and testing on a 600-word commonly used Chinese character set, the recognition results indicate that the user adaptation module significantly improved the recognition accuracy. The average recognition rate increased from 44.2% to 82.4% in five adapting cycles, and the performance could finally increase up to 90.2% in ten adapting cycles.

Protection abilities of influenza B virus DNA vaccines expressing hemagglutinin, neuraminidase, or both in mice

Every year, a vaccination against Influenza B virus (IBV) is essential due to an antigenic variation. Development of an efficient and convenient vaccine is important for the prevention of viral infection. This study reports examination of the protective immunity in mice evoked by a single inoculation of plasmid DNA expressing hemagglutinin (HA DNA) or neuraminidase (NA DNA) of IBV. The HA DNA or NA DNA was injected intramuscularly into BALB/c mice separately or as a mixture. The injection of plasmid was followed by an electroporation close to the site of puncture. Four weeks later, the immunized mice were challenged with a lethal dose of IBV. The protective abilities of DNA vaccines were evaluated by the detection of specific antibodies in serum, survival rate, virus titer in lungs, and change of body weight. We found that a single dose of HA DNA or NA DNA induced the formation of specific antibodies and conferred effective protection against the lethal challenge of IBV. However, the combined vaccine HA DNA and NA DNA enhanced the protective ability of immunized mice. The obtained results suggested that immunization with single dose of HA DNA, NA DNA or with combination of both could be an efficient method for preventing IBV infection.

Effect of microwave annealing temperatures on lead zirconate titanate thin films

Lead zirconate titanate (Pb(1.1)(Zr(0.52)Ti(0.48))O(3)) thin films of thickness 260 nm on Pt/Ti/SiO(2)/Si substrates were densified by 2.45 GHz microwave annealing. The PZT thin films were annealed at various annealing temperatures from 400 to 700 °C for 30 min. X-ray diffraction showed that the pyrochlore phase was transformed to the perovskite phase at 450 °C and the film was fully crystallized. The secondary (again pyrochlore) phase was observed in the PZT thin films, which were annealed above 550 °C. The surface morphologies were changed above 550 °C of the PZT thin films due to the secondary phase. Higher dielectric constant (ε(r)) and lower dielectric loss coercive field (E(c)) were achieved for the 450 °C film than for the other annealed films.

Actin-based modeling of a transcriptionally competent nuclear substructure induced by transcription inhibition

During transcription inactivation, the nuclear bodies in the mammalian cells often undergo reorganization. In particular, the interchromatin granule clusters, or IGCs, become colocalized with RNA polymerase II (RNAP II) upon treatment with transcription inhibitors. This colocalization has also been observed in untreated but transcriptionally inactive cells. We report here that the reorganized IGC domains are unique substructure consisting of outer shells made of SC35, ERK2, SF2/ASF, and actin. The apparently hollow holes of these domains contain clusters of RNAP II, mostly phosphorylated, and the splicing regulator SMN. This class of complexes are also the sites where prominent transcription activities are detected once the inhibitors are removed. Furthermore, actin polymerization is required for reorganization of the IGCs. In connection with this, immunoprecipitation and immunostaining experiments showed that nuclear actin is associated with IGCs and the reorganized IGC domains. The study thus provides further evidence for the existence of an actin-based nuclear skeleton structure in association with the dynamic reorganization processes in the nucleus. Overall, our data suggest that mammalian cells have adapted to utilize the reorganized, uniquely shaped IGC domains as the temporary storage sites of RNAP II transcription machineries in response to certain transient states of transcription inactivation.

GSK3 beta mediates suppression of cyclin D2 expression by tumor suppressor PTEN

PTEN, encoding a lipid phosphatase, is a tumor suppressor gene and is mutated in various types of cancers. It is reported to regulate G1 to S phase transition of the cell cycle by influencing the expression, protein stability and subcellular location of cyclin D1. Here, we provide evidence that PTEN modulates the transcription and protein stability of cyclin D2. Targeted deletion of Pten in mouse embryonic fibroblasts (MEFs) endowed cells with greater potential to overcome G1 arrest than wild-type MEFs and led to the elevated expression of cyclin D2, which was suppressed by the introduction of PTEN. We further defined a pathway involving GSK3beta and beta-catenin/TCF in PTEN-mediated suppression of cyclin D2 transcription. LiCl, an inhibitor of GSK3beta, abolished inhibitory effect of PTEN on cyclin D2 expression, and TCF members could directly bind to the promoter of cyclin D2 and regulate its transcription in a CREB-dependent manner. Our results indicate that the downregulation of cyclin D2 expression by PTEN is mediated by the GSK3beta/beta-catenin/TCF pathway in cooperation with CREB, and suggest a convergence from the PI-3 kinase/PTEN pathway and the Wnt pathway in modulation of cyclin D2 expression.

Cell-type-specific limitation on in vivo serotonin storage following ectopic expression of the Drosophila serotonin transporter, dSERT

The synaptic machinery for neurotransmitter storage is cell-type specific. Although most elements of biosynthesis and transport have been identified, it remains unclear whether additional factors may be required to maintain this specificity. The Drosophila serotonin transporter (dSERT) is normally expressed exclusively in serotonin (5-HT) neurons in the CNS. Here we examine the effects of ectopic transcriptional expression of dSERT in the Drosophila larval CNS. We find a surprising limitation on 5-HT storage following ectopic expression of dSERT and green fluorescence protein-tagged dSERT (GFP-dSERT). When dSERT transcription is driven ectopically in the CNS, 5-HT is detectable only in 5-HT, dopamine (DA), and a very limited number of additional neurons. Addition of exogenous 5-HT does not dramatically broaden neuronal storage sites, so this limitation is only partly due to restricted intercellular diffusion of 5-HT. Furthermore, this limitation is not due to gross mislocalization of dSERT, because cells lacking or containing 5-HT show similar levels and subcellular distribution of GFP-dSERT protein, nor is it due to lack of the vesicular transporter, dVMAT. These data suggest that a small number of neurons selectively express factor(s) required for 5-HT storage, and potentially for function of dSERT.

Transformation of yeast by infectious prion particles

We present methods to prepare infectious Sup35 protein aggregates and use them for genetic transformation of yeast. The protein aggregates are prepared from bacterially expressed recombinant protein, which is converted to amyloid fibers by extended incubation or by nucleated growth using yeast prion particles as seeds. The aggregates are introduced into yeast by a modified spheroplast transformation protocol. The phenotype of the yeast transformants is further characterized by robust prion strain typing methods. The methodology can be used to introduce different [PSI(+)] particles to many laboratory yeast genetic backgrounds. It can be adapted for applications in other yeast prion systems as well.

Tuberculous peritonitis in a haemodialysis patient with elevated serum CA 125 and hypercalcaemia

CA 125, a glycoprotein derived from coelomic epithelium, is used primarily as a marker of epithelial ovarian cancer. However, elevated levels of serum CA 125 have also been detected in other benign and malignant disorders. This study describes a haemodialysis patient who contracted tuberculous peritonitis associated with hypercalcaemia, erythropoietin-resistant anaemia and elevated CA 125, which normalised gradually following antituberculosis treatment. Tuberculous peritonitis should be considered in the differential diagnosis of ascites with elevated serum CA 125. Additionally, CA 125 is a useful marker for monitoring response to tuberculous peritonitis treatment.