Effect of low temperatures on BAX and BCL2 proteins in rats with spinal cord ischemia reperfusion injury

We evaluated changes in BAX and BCL2 expression levels after spinal cord ischemia/reperfusion injury (SCII) and hypothermia during operations in rats. Eighty rats were divided into four groups: Group A (N = 20, 18°C); Group B (N = 20, 28°C); Group C (N = 20, room temperature); and Group D (N = 20, sham operation control). Spinal cord ischemia was induced for 90 min. Hypothermia was induced 15 min before, and maintained during ischemia, followed by heating to normothermia for 30 min after reperfusion. Motor function of the lower limbs was evaluated according to the Tarlov score at 72 and 168 h. For each rat, spinal cord samples were taken at 6, 24, 72 h, and 1 week to evaluate the histopathological changes, neuronal apoptosis, and BAX and BCL2 expression levels. Compared with normothermia, hypothermia significantly improved hind limb function; Group B achieved a higher score than Group A. Group D showed no neurologic deficiency, while the other groups showed various degrees. Group C exhibited greater neuronal apoptosis, higher BAX expression, but lower BCL2 expression than the other groups. Compared with Group A, BAX was expressed less and BCL2 more in Group B, and there was less apoptosis in Group B. Hypothermia preserves hind limb motor function and reduces neuronal death, thereby protecting rats from SCII. The spinal cord may be protected from SCII by inhibition of BAX and activation of BCL2. However, deep hypothermia may inhibit the expression of BCL2, resulting in a worse outcome than mild hypothermia.

Nano-level position resolution for particle tracking in digital in-line holographic microscopy

Three-dimensional particle tracking in biological systems is a quickly growing field, many techniques have been developed providing tracking characters. Digital in-line holographic microscopy is a valuable technique for particle tracking. However, the speckle noise, out-of-focus signals and twin image influenced the particle tracking. Here an adaptive noise reduction method based on bidimensional ensemble empirical mode decomposition is introduced into digital in-line holographic microscopy. It can eliminate the speckle noise and background of the hologram adaptively. Combined with the three-dimensional deconvolution approach in the reconstruction, the particle feature would be identified effectively. Tracking the fixed beads on the cover-glass with piezoelectric stage through multiple holographic images demonstrate the tracking resolution, which approaches 2 nm in axial direction and 1 nm in transverse direction. This would facilitate the development and use in the biological area such as living cells and single-molecule approaches.

Generation of Foxo3-targeted Mice by Injection of mRNAs Encoding Transcription Activator-like Effector Nucleases (TALENs) into Zygotes

In this study, for exploring the mechanism of forkhead box O3(Foxo3) participating in regulation of the activation of primordial oocytes, Foxo3-targeted mice were generated by injection of mRNAs encoding transcription activator-like effector nucleases (TALENs) into mouse zygotes. The TALEN sites were designed with high conservative homologous region among pig, bovine, buffalo and mouse by commercial bio-companies. The TALENs mutagenic non-homologous end-joining (NHEJ) repair activity were determined to be 31.3% in human embryonic kidney 293T (HEK-293T) cells by dual luciferase reporter assay system. Then, we firstly injected TALEN-mRNAs into the cytoplasm of mouse zygotes by micromanipulation, and four of 48 mouse blastocysts were identified as mutation by sequencing. Subsequently, by the method of TALEN-mRNAs injected into the zygotes with pronucleus micromanipulation technique, we obtained seven Foxo3 mutants of 20 FVB/NJ backgrounds mice which were Foxo3-independent alleles with frameshift and deletion mutations. It was very interesting that all seven were heterozygous mutants (Foxo3(-/+) ), and the gene mutagenesis rates of the mice reached 35%. The five Foxo3 mutant females were all infertile in the following 6 months after birth. The histological examination results showed that there were rare primordial follicles and primary follicles in the ovary of Foxo3 mutant compared to that of wide-type female mice. Moreover, one of two mutant males was subfertile and another was fertile normally. Those results suggested that the mutant of Foxo3 severely affected the fertile ability of female and perhaps male in some degree; furthermore, an even more efficient TALENs-based gene mutation method has been established to be poised to revolutionize the study of mouse and other species genetics.

PCDH20 functions as a tumour-suppressor gene through antagonizing the Wnt/β-catenin signalling pathway in hepatocellular carcinoma

Several members of protocadherins have been found involved in human carcinogenesis, but little is known about PCDH20 in HCC. Here in this study, using quantitative real-time RT-PCR assay, we demonstrated the downregulation of PCDH20 expression in 6 of 7 HCC cell lines tested. Similarly, PCDH20 expression in primary HCC tissues was also significantly downregulated in comparison with that in either disease-free normal liver tissues or the adjacent nontumour liver tissues (P < 0.001, respectively). Among HCC tumour tissues studied, about 48% (51/107) of them showed reduced PCDH20 mRNA level. Further statistic analysis revealed that the reduced PCDH20 mRNA level in tumour tissues was much more common in younger patients group (aged <50 years) than that in older group (≥50 years) (60% vs 33%, P = 0.0303). Loss of heterozygosity (LOH) and promoter hypermethylation analysis revealed that deletion and/or aberrant epigenetic modulation of PCDH20 gene account for its downregulation, at least in a fraction of tumour specimens. Moreover, ectopic expression of PCDH20 in HCC cells significantly suppressed cell proliferation, clonogenicity, migration and tumour formation. Notably, we proved for the first time that, via activating GSK-3β, PCDH20 could inhibit Wnt/β-catenin signalling pathway. Furthermore, our data suggest that PCDH20 may conduct its Wnt/β-catenin signalling antagonizing function through suppressing Akt and Erk activities and promoting GSK-3β signalling activities. However, the detailed mechanism remained undiscovered. In conclusion, our data here strongly suggested that PCDH20 may act as a candidate tumour suppressor in HCC.

Glycolysis recycling of rigid waste polyurethane foam from refrigerators

Rapid growth of rigid waste polyurethane (WPUR) foam from refrigerators attracts the attention all over the world. In this study, glycolysis was chosen to treat WPUR from scrapped refrigerators collected in Shanghai, China. Glycolysis reagents and catalysts were selected. The results indicated that the glycolysis efficiency of ethylene glycol (EG) was higher than that of diethylene glycol, and the catalytic efficiency of alkali metal salts (NaOH) was more excellent than that of triethanolamine and organic salts of alkali metal (NaAc). When EG was 100%WPUR as a glycolysis reagent and NaOH was 1%WPUR as a catalyst at a constant temperature of 197.85°C for 2 h, the glycolysis product had the highest glycolysis conversion rate. In order to maximize the recycling of WPUR, regenerative Polyurethane was performed by adding 10% distilled mixed polyol, which conformed to the QB/T 26689-2011 requirements.

Prevention of etomidate-induced myoclonus during anesthetic induction by pretreatment with dexmedetomidine

Myoclonus induced by etomidate during induction of general anesthesia is undesirable. This study evaluated the effect of dexmedetomidine (DEX) pretreatment on the incidence and severity of etomidate-induced myoclonus. Ninety patients undergoing elective surgical procedures were randomly allocated to three groups (n=30 each) for intravenous administration of 10 mL isotonic saline (group I), 0.5 µg/kg DEX in 10 mL isotonic saline (group II), or 1.0 µg/kg DEX in 10 mL isotonic saline (group III) over 10 min. All groups subsequently received 0.3 mg/kg etomidate by intravenous push injection. The incidence and severity of myoclonus were recorded for 1 min after etomidate administration and the incidence of cardiovascular adverse events that occurred between the administration of the DEX infusion and 1 min after tracheal intubation was recorded. The incidence of myoclonus was significantly reduced in groups II and III (30.0 and 36.7%), compared with group I (63.3%). The incidence of severe sinus bradycardia was significantly increased in group III compared with group I (P<0.05), but there was no significant difference in heart rate in groups I and II. There were no significant differences in the incidence of low blood pressure among the 3 groups. Pretreatment with 0.5 and 1.0 µg/kg DEX significantly reduced the incidence of etomidate-induced myoclonus during anesthetic induction; however, 0.5 µg/kg DEX is recommended because it had fewer side effects.

Abstract 3081: Isolation and identification of circulating tumor cells in renal cell carcinoma

Background: Renal cell carcinoma (RCC) is the most common type of kidney cancer responsible for ∼80% of kidney cancer cases. Circulating tumor cells (CTCs) are emerging as an important prognostic and predictive biomarker in several types of metastatic cancers. However, methods for CTC detection that target only EpCAM and/or cytokeratin (CK) to enrich CTCs, may fail to recognize the CTCs in clear cell RCC (ccRCC) because ccRCC lacks expression of EpCAM. The objective of this study was to develop a new technology capable of detecting CTCs including those with a mesenchymal phenotype in metastatic RCC.

Methods: Blood samples from patients affected by metastatic RCC were provided by Mayo Clinic Arizona and analyzed by Creatv MicroTech. CellSieveTM microfilters, which have 7 µm diameter pores in a uniform array, with 160,000 pores in a 9 mm diameter area, were used for separation of CTCs in the blood specimen. 7.5 mL of whole blood was diluted in the prefixation buffer and filtered through the microfilter. Clinical immunohistochemical markers for RCC such as CD10 and vimentin were used to identify candidate CTCs. The cells collected on the filter were fixed, permeabilized, and stained with DAPI and fluorescent antibodies specific to CD10, vimentin, and CD45. The assay protocol was developed using three RCC cell lines, 786-O, Caki-1, and Caki-2, and validated using blood samples from patients with metastatic RCC.

Results: The capture efficiencies for 786-O, Caki-1, and Caki-2 cell lines were determined to be 98%, 98% and 97%, respectively. On-filter antibody staining revealed heterogeneous expressions of vimentin and CD10 in RCC cells. Patient samples were collected in duplicate CellSaveTM tubes and processed one day later. A CD10+/vimentin+/CD45- cell population was detected in blood samples with enumeration ranging from 4 to 86 cells/7.5 mL of blood. We found that the RCC CTC profile was distinct from other types of cancers. The typical CTCs display abnormal morphology, including large nuclei (typically 15-30 µm in size), irregular cell size and shape, and high nucleus-to-cytoplasm ratio. Although CD10 and vimentin antibodies have cross-reactivity with white blood cells (WBC), the CTCs could be distinguished from WBC based on morphology, cell size and CD45- staining.

Conclusions: We demonstrated that the CellSieveTM microfiltration assay is a very simple and efficient method to isolate a CD10+/vimentin+/CD45- cell population from patients affected by metastatic ccRCC. Future studies include fluorescence in situ hybridization to confirm loss of 3p, a molecular event that occurs in &gt;90% of ccRCC. We are also analyzing blood samples from patients treated with tyrosine kinase inhibitors to determine if cell enumeration is predictive of response to treatment. This technology might greatly facilitate detection of EpCAM negative ccRCC CTCs. The clinical significance of these unusual, large, rod-shaped, naked nuclei require further molecular characterization.

Citation Format: Peixuan Zhu, Thai Ho, Erik P. Castle, Richard W. Joseph, Melissa L. Stanton, Shuhong Li, Daniel Adams, Olga V. Makarova, Platte T. Amstutz, Cha-Mei Tang. Isolation and identification of circulating tumor cells in renal cell carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3081. doi:10.1158/1538-7445.AM2014-3081

TMPRSS2:ERG blocks neuroendocrine and luminal cell differentiation to maintain prostate cancer proliferation

The biological outcome of TMPRSS2:ERG chromosomal translocations in prostate cancer (PC) remains poorly understood. To address this, we compared the transcriptional effects of TMPRSS2:ERG expression in a transgenic mouse model with those of ERG knockdown in a TMPRSS2:ERG-positive PC cell line. This reveals that ERG represses the expression of a previously unreported set of androgen receptor (AR)-independent neuronal genes that are indicative of neuroendocrine (NE) cell differentiation-in addition to previously reported AR-regulated luminal genes. Cell sorting and proliferation assays performed after sustained ERG knockdown indicate that ERG drives proliferation and blocks the differentiation of prostate cells to both NE and luminal cell types. Inhibition of ERG expression in TMPRSS2:ERG-positive PC cells through blockade of AR signaling is tracked with increased NE gene expression. We also provide evidence that these NE cells are resistant to pharmacological AR inhibition and can revert to the phenotype of parental cells upon restoration of AR/ERG signaling. Our findings highlight an ERG-regulated mechanism capable of repopulating the parent tumor through the transient generation of an anti-androgen therapy-resistant cell population, suggesting that ERG may have a direct role in preventing resistance to anti-androgen therapy.

Computational fluid dynamics analysis of salivary flow and its effect on sialolithogenesis

OBJECTIVE

Sialolithiasis is a common disease caused by intraductal stones, formed by reduction in salivary flow, salivary stagnation, and metabolic events. We used computational fluid dynamics to investigate changes in salivary flow field around parotid stones of different shapes.

MATERIALS AND METHODS

Three-dimensional configurations of the Stensen's duct were reconstructed from computed tomography sialographic images. Fluid dynamics modeling was used to analyze the salivary flow field around stones under unstimulated and stimulated conditions.

RESULTS

The majority of sialoliths were oval-shaped (59/98), followed by irregular (24/98) and round (15/98). Salivary velocity was significantly higher around streamlined stones, compared with round (P = 0.013) and oval (P = 0.025) types. Changes in salivary flow field around sialoliths were found to affect the pattern of mineral deposition in saliva. The area of low velocity around the round stone was double the size observed around the streamlined stone during the unstimulated state, whereas in the stimulated state, local vortexes were formed on the downstream side of round and oval stones.

CONCLUSIONS

Salivary flow field around sialoliths plays an important role in the progression of multicentric stones, and analysis of the salivary dynamics during sialolithiasis may provide deeper understandings of the condition and aid in developing successful treatment strategies.

Probing the repulsive core of the nucleon-nucleon interaction via the (4)He(e,e'pN) triple-coincidence reaction

We studied simultaneously the (4)He(e,e'p), (4)He(e,e'pp), and (4)He(e,e'pn) reactions at Q(2)=2(GeV/c)(2) and x(B)>1, for an (e,e'p) missing-momentum range of 400 to 830  MeV/c. The knocked-out proton was detected in coincidence with a proton or neutron recoiling almost back to back to the missing momentum, leaving the residual A=2 system at low excitation energy. These data were used to identify two-nucleon short-range correlated pairs and to deduce their isospin structure as a function of missing momentum, in a region where the nucleon-nucleon (NN) force is expected to change from predominantly tensor to repulsive. The abundance of neutron-proton pairs is reduced as the nucleon momentum increases beyond ∼500  MeV/c. The extracted fraction of proton-proton pairs is small and almost independent of the missing momentum. Our data are compared with calculations of two-nucleon momentum distributions in (4)He and discussed in the context of probing the elusive repulsive component of the NN force.

Long-term outcomes after nucleos(t)ide analogue discontinuation in HBeAg-positive chronic hepatitis B patients

Nucleos(t)ide analogue (NUC) resistance is an important clinical risk resulting from long-term therapy in chronic hepatitis B (CHB) management. Discontinuation of NUCs is a feasible strategy to reduce resistance. We aimed to observe the outcomes after NUC withdrawal in HBeAg-positive CHB patients. A total of 97 patients (11 patients with HBsAg loss and 86 patients with sustained HBeAg seroconversion) were enrolled. HBV DNA levels and alanine aminotransferase (ALT) levels were monitored regularly after discontinuation. Relapse was defined as HBV DNA levels >2000 IU/mL in at least two determinations more than 4 weeks apart. HBeAg seroconversion was achieved within 48 weeks (interquartile range (IQR), 24-72 weeks). The time on consolidation therapy was 96 weeks (IQR, 84-144 weeks). No relapses occurred for HBsAg loss patients. Evidence of relapse was observed in 9.3% of HBeAg seroconversion patients. All relapse cases occurred within 48 weeks after discontinuation. The time to relapse was 33 ± 15 weeks. Elevation of HBV DNA and ALT levels over baseline were only observed in 12.5% of relapse patients. There were no significant differences in baseline characteristics (sex, HBV genotype, age or ALT levels) or time on consolidation therapy between patients with relapse or sustained response. NUC discontinuation in HBeAg-positive CHB patients is feasible after achieving HBeAg seroconversion at a minimum of 24 weeks. There is further benefit to prolonging the time on consolidation therapy to reduce relapse. More than 48 weeks of sustained response is a predictive marker for long-term sustained response.

Chinese SLE Treatment and Research group (CSTAR) registry: II. Prevalence and risk factors of pulmonary arterial hypertension in Chinese patients with systemic lupus erythematosus

Objectives

To estimate the prevalence of pulmonary arterial hypertension (PAH) and risk factors for PAH in patients registered in the Chinese SLE Treatment and Research group (CSTAR) database, the first online registry of Chinese patients with systemic lupus erythematosus (SLE).

Methods

A prospective cross-sectional study of patients with SLE was conducted using the CSTAR registry. Resting transthoracic echocardiography was used to estimate pulmonary artery pressure (PAP); PAH was defined as systolic PAP (PASP) ≥40 mmHg. Patients with interstitial lung disease, valvular disease or cardiomyopathy were excluded because of disease influence on PAP. We explored potential risk factors for PAH including patient characteristics, organ involvement, laboratory findings and SLE disease activity.

Results

Of 1934 patients with SLE, 74 had PASP with 54.2 ± 17.1 (40,106) mmHg and were diagnosed with probable PAH. The incidences of lupus nephritis, pleuritis, pericarditis, hypocomplementemia, anti-SSA, and anti-ribonucleoprotein (RNP) were significantly higher in patients with PAH than in those without ( p<0.05). SLE disease activity was significantly higher in patients with PAH than in unaffected patients ( p<0.05). Multivariate analysis indicated that pericarditis (odds ratio (OR) = 4.248), pleuritis (OR = 3.061) and anti-RNP (OR = 2.559) were independent risk factors for PAH in patients with SLE ( p<0.05).

Conclusions

The possible prevalence of PAH was 3.8% in Chinese patients with SLE in the CSTAR registry. The significant association of pericarditis, pleuritis and anti-RNP positivity with PAH suggests that higher disease activity and vasculopathy may both contribute to the development of PAH in SLE, which need be treated aggressively to improve prognosis.

Analysis of antithrombotic therapy in elderly patients with atrial fibrillation

This study aimed to analyze the impact factors and outcome of antithrombotic therapy in elderly patients over 65 years old that suffered from atrial fibrillation (AF). A total of 256 elderly patients with AF over 65 years old were divided into 3 groups: 65-74 years old (N = 86), 75-84 years old (N = 122), and over 85 years old (N = 48). The clinical characteristics, antithrombotic therapy, and its related impact factors were retrospectively analyzed. Of all patients, 187 received antithrombotic therapy. In the 65-74 year-old group, 78 patients received antiplatelet treatment (90.7%) and 5 patients received anticoagulation treatment (5.8%). In the 75-84 year-old group, 76 patients received antiplatelet treatment (62.3%) and 14 patients received anticoagulation treatment (11.5%). In the group of over 85 year-olds, 33 patients received antiplatelet therapy (68.8%) and 4 patients received anticoagulation treatment (8.3%). Eleven patients had deep vein thrombosis and atrial thrombosis during antiplatelet therapy (5.9%), 5 patients had gastrointestinal hemorrhage after antiplatelet therapy (2.7%), 2 patients had gastrointestinal bleeding, and 3 patients had brain hemorrhage after anticoagulation treatment (21.7%). Suboptimal antithrombotic therapy was observed in the elderly patients with AF, partly owing to the risks of both thromboembolism and bleeding.