An Evidence-based Recommendation for a Standardized Approach to Detecting Metastatic Neuroblastoma in Staging Bone Marrow Biopsies

Neuroblastoma is a common malignant tumor of childhood. Accurate bone marrow (BM) evaluation for metastatic tumor is essential; however, no standardized pathologic workup exists for staging BMs. We examined the diagnostic yield of various BM components and optimal core biopsy (CB) length as part of developing evidence-based recommendations for BM evaluation. After obtaining institutional review board approval, 160 BM biopsies from 50 neuroblastoma patients were retrospectively selected. Hematoxylin and eosin-stained CB and Wright-stained aspirates were scored as positive, negative, or indeterminate. Total/trabecular CB lengths were measured using cellSens software and a DP71 camera (Olympus). Of the 160 BMs, 72 were positive for tumor in any component. Of these, 33 (45.8%) were positive in a single portion of the specimen: 19 CBs and 14 aspirates. Compared with overall diagnosis, sensitivities were as follows: CB 76.3%; aspirate 67.1%; core/aspirate combined 94.7%. Diagnostic CBs had significantly longer trabecular length than nondiagnostic CBs (6.74 mm vs 4.03 mm, P = .006). Positive CBs had longer trabecular space than negative marrows (7.91 mm vs 6.25 mm, P = .002). Nearly 50% of our positive specimens showed diagnostic discordance among the various components examined. However, combining CB and aspirate examination improved sensitivity for tumor detection. We therefore recommend bilateral CBs (>1 cm each) and aspirates for the optimal evaluation of BM for metastatic neuroblastoma.

Molecular genetic analysis of 30 families with Joubert syndrome

Joubert syndrome (JS) is rare recessive disorders characterized by the combination of hypoplasia/aplasia of the cerebellar vermis, thickened and elongated superior cerebellar peduncles, and a deep interpeduncular fossa which is defined by neuroimaging and is termed the 'molar tooth sign'. JS is genetically highly heterogeneous, with at least 29 disease genes being involved. To further understand the genetic causes of JS, we performed whole-exome sequencing in 24 newly recruited JS families. Together with six previously reported families, we identified causative mutations in 25 out of 30 (24 + 6) families (83.3%). We identified eight mutated genes in 27 (21 + 6) Japanese families, TMEM67 (7/27, 25.9%) and CEP290 (6/27, 22.2%) were the most commonly mutated. Interestingly, 9 of 12 CEP290 disease alleles were c.6012-12T>A (75.0%), an allele that has not been reported in non-Japanese populations. Therefore c.6012-12T>A is a common allele in the Japanese population. Importantly, one Japanese and one Omani families carried compound biallelic mutations in two distinct genes (TMEM67/RPGRIP1L and TMEM138/BBS1, respectively). BBS1 is the causative gene in Bardet-Biedl syndrome. These concomitant mutations led to severe and/or complex clinical features in the patients, suggesting combined effects of different mutant genes.

Stalled replication forks within heterochromatin require ATRX for protection

Expansive growth of neural progenitor cells (NPCs) is a prerequisite to the temporal waves of neuronal differentiation that generate the six-layered neocortex, while also placing a heavy burden on proteins that regulate chromatin packaging and genome integrity. This problem is further reflected by the growing number of developmental disorders caused by mutations in chromatin regulators. ATRX gene mutations cause a severe intellectual disability disorder (α-thalassemia mental retardation X-linked (ATRX) syndrome; OMIM no. 301040), characterized by microcephaly, urogenital abnormalities and α-thalassemia. Although the ATRX protein is required for the maintenance of repetitive DNA within heterochromatin, how this translates to disease pathogenesis remain poorly understood and was a focus of this study. We demonstrate that Atrx(FoxG1Cre) forebrain-specific conditional knockout mice display poly(ADP-ribose) polymerase-1 (Parp-1) hyperactivation during neurogenesis and generate fewer late-born Cux1- and Brn2-positive neurons that accounts for the reduced cortical size. Moreover, DNA damage, induced Parp-1 and Atm activation is elevated in progenitor cells and contributes to their increased level of cell death. ATRX-null HeLa cells are similarly sensitive to hydroxyurea-induced replication stress, accumulate DNA damage and proliferate poorly. Impaired BRCA1-RAD51 colocalization and PARP-1 hyperactivation indicated that stalled replication forks are not efficiently protected. DNA fiber assays confirmed that MRE11 degradation of stalled replication forks was rampant in the absence of ATRX or DAXX. Indeed, fork degradation in ATRX-null cells could be attenuated by treatment with the MRE11 inhibitor mirin, or exacerbated by inhibiting PARP-1 activity. Taken together, these results suggest that ATRX is required to limit replication stress during cellular proliferation, whereas upregulation of PARP-1 activity functions as a compensatory mechanism to protect stalled forks, limiting genomic damage, and facilitating late-born neuron production.

[Effect of thermo-sensitive Matrigel on minimization of thermal injury to the nearby structures in radiofrequency ablation of subcapsular hepatic tumors in a rat model]

OBJECTIVE

To evaluate the effect and safety of using thermo-sensitive Matrigel as artificial ascites on minimizing thermal injury to the nearby structures in a rat model of radiofrequency (RF) ablation of the liver.

METHODS

In this research, the morphological characterization of Matrigel was observed at different temperatures in vitro. In vivo study was conducted by using 42 SD rats in Matrigel, Saline and control groups of 14 rats each. Artificial ascites with 10 ml of Matrigel or saline was produced under ultrasound guidance before RF in the experimental groups. Using a 0.7 cm exposed 17 G RF electrode for 5 minutes (90 ± 2) ℃, 41 hepatic ablations was performed abutting the diaphragm, abdominal wall and stomach. The 41 rats were sacrificed at 24 h, and necropsy was performed.Gross and histopathologic examinations were performed to compare the frequency and extent of thermal injury to the nearby organs.The animal status was followed up to achieve long term safety evaluation of Matrigel.

RESULTS

Matrigel was in liquid formation at 0-4 ℃, but was not moving in vials at temperature 37 ℃ in 1 min, presenting gel formation.In vivo experiment, the artificial fluid thickness of Matrigel in site was significant larger than that of saline group, especially at 5 min of ablation ((8.1 ± 1.1) mm vs (2.4 ± 0.8)mm, P<0.01). Thermal injury to the nearby structures was found in 12 of 13 cases in control group, 8 of 14 cases (P=0.037) in saline group, and 1 of 14 cases (P<0.01) in Matrigel group. The sizes of the ablation zone of the liver did not differ among the three groups. There was no difference in the incidence of operation related complications among the three groups. There was no significant difference in body weight and health related parameters between Matrigel and saline group during 60 days of follow up.

CONCLUSIONS

Using thermo-sensitive Matrigel as artificial ascites may be a safe and useful technique and help to further reduce the frequency and severity of collateral thermal injury to the nearby structures compare to conventional saline, during RF ablation of subcapsular hepatic tumors.

Simultaneous Determination and Pharmacokinetic Study of Protocatechuic Aldehyde and Its Major Active Metabolite Protocatechuic Acid in Rat Plasma by Liquid Chromatography-Tandem Mass Spectrometry

A very simple and selective high-performance liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS-MS) method was developed for simultaneous determination and pharmacokinetic study of protocatechuic aldehyde (PAL) and its active metabolite protocatechuic acid (PCA). The method involves a simple liquid-liquid extraction with ethyl acetate. The separation was performed on a Hypersil GOLD C18 column (2.1 × 150 mm, 3.0 µm; particle, Thermo, USA) with isocratic elution using a mobile phase consisted of methanol and water (containing 0.1% formic acid) at a flow rate of 0.2 mL/min. The detection of target compounds was done by using low-energy collision dissociation tandem mass spectrometry (CID-MS-MS) using the selective reaction monitoring scan mode. The method was linear for all analytes over the investigated range for all correlation coefficients greater than 0.9950. The lower limits of quantification were 2.0 ng/mL for PAL and PCA. The intra- and interday precisions (relative standard deviation, RSD %) were <6.84 and 5.54%, and the accuracy (relative error, RE %) was between -2.85 and 0.74% (n = 6). The developed method was applied to study the pharmacokinetics of PAL and its major active metabolite PCA in rat plasma after oral and intravenous administration of PAL.

Identification of a major metabolite of danshensu in rat urine and simultaneous determination of danshensu and its metabolite in plasma: application to a pharmacokinetic study in rats

Danshensu, as the effective component of Salvia miltiorrhiza (Danshen), has been widely used in clinical studies for treatment of cardiovascular diseases in China. A new metabolite, 4-hydroxy-3-methoxyphenyllactic acid was isolated from the urine of rats, and its chemical structure was identified by ultraviolet (UV), Infrared Spectroscopy (IR), mass spectrometry (MS) and nuclear magnetic resonance (NMR). Furthermore, a selective and sensitive high performance liquid chromatography-tandem mass spectrometric (HPLC-MS/MS) method was developed for the simultaneous quantification of danshensu and its major metabolite, 4-hydroxy-3-methoxyphenyllactic acid, in rat plasma after oral and intravenous administration of danshensu. The separation was performed on a Hypersil Gold C18 column (150 × 2.1 mm i.d., 3.0 µm, Thermo, San jose CA, USA) with gradient elution using a mobile phase composed of methanol and water (containing 0.1% formic acid) at a flow rate of 0.2 mL/min. Linear detection responses were obtained for danshensu and 4-hydroxy-3-methoxyphenyllactic acid ranging from 5 to 10000 ng/mL and 5 to 4000 ng/mL, respectively. The lower limits of quantification (LLOQs) for the two compounds were both 5 ng/mL. The intra-and inter-day precision (R.S.D %) were within 5.61% for the two analytes. The average recoveries of the analytes were greater than 72.43%. The method was proved to be stable during all sample storage, preparation and analytic procedures. This method was successfully applied to the pharmacokinetic studies of danshensu and 4-hydroxy-3-methoxyphenyllactic acid after oral and intravenous administration of danshensu in rats.

K63-linked ubiquitination of FANCG is required for its association with the Rap80-BRCA1 complex to modulate homologous recombination repair of DNA interstand crosslinks

DNA interstrand crosslinks (ICLs) are extremely deleterious lesions that are repaired by homologous recombination (HR) through coordination of Fanconi anemia (FA) proteins and breast cancer susceptibility gene 1 (BRCA1) product, but the exact role these proteins have remains unclear. Here we report that FANCG was modified by the addition of lysine63-linked polyubiquitin chains (K63Ub) in response to DNA damage. We show that FANCG K63Ub was dispensable for monoubiquitination of FANCD2, but was required for FANCG to interact with the Rap80-BRCA1 (receptor-associated protein 80-BRCA1) complex for subsequent modulation of HR repair of ICLs induced by mitomycin C. Mutation of three lysine residues within FANCG to arginine (K182, K258 and K347, 3KR) reduced FANCG K63Ub modification, as well as its interaction with the Rap80-BRCA1 complex, and therefore impeded HR repair. In addition, we demonstrated that K63Ub-modified FANCG was deubiquitinated by BRCC36 complex in vitro and in vivo. Inhibition of BRCC36 resulted in increased K63Ub modification of FANCG. Taken together, our results identify a new role of FANCG in HR repair of ICL through K63Ub-mediated interaction with the Rap80-BRCA1 complex.

Value of ecosystem hydropower service and its impact on the payment for ecosystem services

Hydropower is an important service provided by ecosystems. We surveyed all the hydropower plants in the Zagunao River Basin, Southwest China. Then, we assessed the hydropower service by using the InVEST (The Integrated Value and Tradeoff of Ecosystem Service Tools) model. Finally, we discussed the impact on ecological compensation. The results showed that: 1) hydropower service value of ecosystems in the Zagunao River Basin is 216.29 Euro/hm(2) on the average, of which the high-value area with more than 475.65 Euro/hm(2) is about 750.37 km(2), accounting for 16.12% of the whole watershed, but it provides 53.47% of the whole watershed service value; 2) ecosystem is an ecological reservoir with a great regulation capacity. Dams cannot completely replace the reservoir water conservation function of ecosystems, and has high economic and environmental costs that must be paid as well. Compensation for water conservation services should become an important basis for ecological compensation of hydropower development. 3) In the current PES cases, the standard of compensation is generally low. Cascade development makes the value of upstream ecosystem services become more prominent, reflecting the differential rent value, and the value of ecosystem services should be based on the distribution of differentiated ecological compensation.

Genomewide analysis of intronic microRNAs in rice and Arabidopsis

MicroRNAs (miRNAs) are potent regulators of gene transcription and posttranscriptional processes. The majority of miRNAs are localized within intronic regions of protein-coding genes (host genes) and have diverse functions in regulating important cellular processes in animals. To date, few plant intronic miRNAs have been studied functionally. Here we report a comprehensive computational analysis to characterize intronic miRNAs in rice and Arabidopsis. RT-PCR analysis confirmed that the identified intronic miRNAs were derived from the real introns of host genes. Interestingly, 13 intronic miRNAs in rice and two in Arabidopsis were located within seven clusters, of which four polycistronic clusters contain miRNAs derived from different families, suggesting that these clustered intronic miRNAs might be involved in extremely complex regulation in rice. Length analysis of miRNA-carrying introns, promoter prediction and qRT-PCR analysis results indicated that intronic miRNAs are coexpressed with their host genes. Expression pattern analysis demonstrated that host genes had a very broad expression spectrum in different stages of development, suggesting the intronic miRNAs might play an important role in plant development. This comparative genomics analysis of intronic miRNAs in rice and Arabidopsis provides new insight into the functions and regulatory mechanisms of intronic miRNAs in monocots and dicots.

A multi-point laser Doppler vibrometer with fiber-based configuration

Laser Doppler vibrometer (LDV) is a non-contact optical interferometric system to measure vibrations of structures and machines with a high precision. Normal LDV can only offer a single-point measurement. Scanning LDV is usually impractical to do measurement on transient events. In this paper, a fiber-based self-synchronized multi-point LDV is proposed. The multiple laser beams with different frequency shifts are generated from one laser source. The beams are projected onto a vibrating object, reflected and interfered with a common reference beam. The signal including vibration information of multiple spatial points is captured by one single-pixel photodetector. The optical system is mainly integrated by fiber components for flexibility in measurement. Two experiments are conducted to measure a steady-state simple harmonic vibration of a cantilever beam and a transient vibration of a beam clamped at both ends. In the first measurement, a numerical interpolation is applied to reconstruct the mode shape with increased number of data points. The vibration mode obtained is compared with that from FEM simulation. In transient vibration measurement, the first five resonant frequencies are obtained. The results show the new-reported fiber-based multipoint LDV can offer a vibration measurement on various spatial points simultaneously. With the flexibility of fiber configuration, it becomes more practical for dynamic structural evaluation in industrial areas.

Barriers faced by migrants in accessing healthcare for viral hepatitis infection

BACKGROUND

The morbidity and mortality of hepatitis B virus- and hepatitis C virus-related complications are disproportionately higher in the culturally and linguistically diverse population (CALD) when compared with Australian-born individuals.

AIM

This project aims to elucidate the barriers faced by the CALD population in accessing viral hepatitis management.

METHOD

CALD outpatients attending a viral hepatitis clinic in a tertiary teaching hospital were invited to participate in interviews. Questions pertained to: reason for screening for viral hepatitis, barriers to healthcare, perceived community view of viral hepatitis, main source of information of viral hepatitis and suggestions to engage members of CALD to seek healthcare.

RESULTS

The total number of participants was 60. The two major countries of birth included China (40%) and Egypt (17%). In 40% of the cohort, viral hepatitis was identified through screening programmes. Importantly, 37% were diagnosed as a result of complications of hepatitis infection, presenting late in the stage of disease. Forty-five per cent of participants perceived language to be a chief barrier. twenty-two per cent reported cultural barriers to accessing healthcare. Of these, 53% reported fear of discrimination/stigma. The lack of knowledge of available treatments/options was stated as a major obstacle in 40%. The two prevailing recommendations were greater education and awareness (85%) and changes in the health system itself (11%).

CONCLUSION

Substantial hurdles identified by participants include cultural differences, language difficulties, cultural beliefs, stigma and misinformation. These data demonstrate the need for the greater dissemination of information in culturally and linguistically appropriate mediums to raise awareness about viral hepatitis, pathogenesis and available treatments.

Clinical study of a noninvasive multimodal sono-contrast induced spectroscopy system for breast cancer diagnosis

PURPOSE

To present a noninvasive multimodal sono-contrast induced spectroscopy (SCIS) system for breast cancer detection.

METHODS

An IRB approved clinical study was carried out to evaluate its diagnostic power. A total of 66 subjects were enrolled with informed consent. The study data were grouped into healthy breast tissue (26), histologically proven cancer (14), and benign mass (26). The diffuse reflectance optical intensity and low intensity focused ultrasound (LIFU) signals, as well as ultrasound images, were collected during each study. The ratio of optical intensities at wavelengths 685 and 830 nm was analyzed using wavelet technique to compare the LIFU effects in cancer and noncancerous tissues. The ultrasound images were also processed to obtain tissue texture parameters, such as correlation, energy, contrast, homogeneity, etc. Backward stepwise regression method was performed to identify the statistically significant factors correlating to tissue types (cancer vs benign mass).

RESULTS

Comparison of the optical signals showed that LIFU induced transitory fluctuation in noncancerous tissue, but not in malignant tissue, as quantified by the ratio of mean absolute deviation (RMAD) of the high frequency component. Statistical analysis revealed that the RMAD ratios were significantly different in tumor vs noncancerous masses (p ≪ 0.01). For tissue texture parameters, energy and correlation were found to statistically correlate with the tissue types. A cancer characterization model was developed using the weighted factors to differentiate the tumor from the benign mass. Trade-off between sensitivity and specificity was obtained by varying the threshold value that estimated the upper-bound of the cancer output factor, from which the receiver-operating characteristic (ROC) curve was generated. The characterization model was optimized using ten modeling datasets and verified using another ten validation datasets randomly generated from the database. The optimization results show that an AUC of 0.93 can be achieved. With threshold 0.3, sensitivity of 96.0%, specificity of 84.1%, and negative predictive value (NPV) of 97.3% can be achieved.

CONCLUSIONS

The feasibility of the multimodal system in characterizing breast cancer vs benign mass is established.

Dynamic Recovery and Recrystallization during Hot-Working in an Advanced TiAl Alloy

Intermetallic TiAl alloys are light-weight high-temperature materials and intended to partly replace Ni based alloys in jet engines. Due to difficult forming operations, component prices are high and limit the possible field of application. During hot-working, recovery and recrystallization effects determine the microstructural evolution and thereby the mechanical properties of the finished part as well as its behavior during deformation. To study the occurring phenomena, in-situ diffraction experiments with high-energy X-rays were conducted. By means of this method, the dominating processes were identified. The results were validated through electron back scatter diffraction experiments.

Octanoylated Ghrelin Inhibits the Activation of the Palmitic Acid-Induced TLR4/NF-κB Signaling Pathway in THP-1 Macrophages

To investigate the effect of acylated ghrelin on the activation of TLR4/NF-κB signaling pathway induced by palmitic acid in human monocyte-derived (THP-1) macrophages, THP-1 macrophages were cultured for 12 h by palmitic acid with various concentrations. The THP-1 macrophages was pretreated by acylated ghrelin at different doses for 4 h before cultivated by palmitic acid (200 μmol/L) for 12 h. We observed the level of TLR4, NF-κB p65 phosphorylation in THP-1 macrophages and TNF-α, IL-1β in culture supernatant. TLR4 mRNA was measured by real-time PCR. TLR4 protein and NF-κB p65 phosphorylation was measured by western blotting. The expression of TNF-α and IL-1β was detected by ELISA. Compared to the THP-1 macrophages without palmitic acid, the level of TLR4 mRNA protein and NF-κB p65 phosphorylation and the expression of TNF-α and IL-1β increased after treatment by palmitic acid in a dose-dependent fashion (P < 0.05). Compared to the THP-1 macrophages with palmitic acid (200 μmol/L), the level of the pervious substances decreased after preadministration by acylated ghrelin in a dose-dependent fashion. So, we make a conclusion that acylated ghrelin can regulate the activation of TLR4/NF-κB signaling pathway and inhibit the release of inflammatory cytokines in THP-1 macrophages which are stimulated by palmitic acid in a dose-dependent fashion.

Urinary podocalyxin is an early marker for podocyte injury in patients with diabetes: establishment of a highly sensitive ELISA to detect urinary podocalyxin

AIMS/OBJECTIVE

Nephropathy, a major complication of diabetes, is the leading cause of end-stage renal disease. Recent studies have demonstrated that podocyte injury is involved in the onset of and progression to renal insufficiency. Here, we describe a novel, highly sensitive ELISA for detecting urinary podocalyxin, a glycoconjugate on the podocyte apical surface that indicates podocyte injury, particularly in the early phase of diabetic nephropathy.

METHODS

Urine samples from patients with glomerular diseases (n = 142) and type 2 diabetes (n = 71) were used to quantify urinary podocalyxin by ELISA. Urine samples were obtained from 69 healthy controls for whom laboratory data were within normal values. Podocalyxin was detected in urine by immunofluorescence, immunoelectron microscopy and western blotting.

RESULTS

Morphologically, urinary podocalyxin was present as a vesicular structure; western blotting showed it as a positive band at 165-170 kDa. Levels of urinary podocalyxin were elevated in patients with various glomerular diseases and patients with diabetes. In patients with diabetes, urinary podocalyxin was higher than the cut-off value in 53.8% patients at the normoalbuminuric stage, 64.7% at the microalbuminuric stage and 66.7% at the macroalbuminuric stage. Positive correlations were observed between urinary podocalyxin levels and HbA(1c), urinary β(2) microglobulin, α(1) microglobulin and urinary N-acetyl-β-D-glucosaminidase, although urinary podocalyxin levels were not correlated with other laboratory markers such as blood pressure, lipid level, serum creatinine, estimated GFR or proteinuria.

CONCLUSIONS/INTERPRETATION

Urinary podocalyxin may be a useful biomarker for detecting early podocyte injury in patients with diabetes.