The regulatory mechanism and therapeutic potential of transcription factor EB in neurodegenerative diseases

The autophagy-lysosomal pathway (ALP) is involved in the degradation of protein aggregates and damaged organelles. Transcription factor EB (TFEB), a major regulator of ALP, has emerged as a leading factor in addressing neurodegenerative disease pathology, including Alzheimer's disease (AD), Parkinson's disease (PD), PolyQ diseases, and Amyotrophic lateral sclerosis (ALS). In this review, we delineate the regulation of TFEB expression and its functions in ALP. Dysfunctions of TFEB and its role in the pathogenesis of several neurodegenerative diseases are reviewed. We summarize the protective effects and molecular mechanisms of some TFEB-targeted agonists in neurodegenerative diseases. We also offer our perspective on analyzing the pros and cons of these agonists in the treatment of neurodegenerative diseases from the perspective of drug development. More studies on the regulatory mechanisms of TFEB in other biological processes will aid our understanding of the application of TFEB-targeted therapy in neurodegeneration.

The phytochemical and pharmacological profile of taraxasterol

Taraxasterol is one of the bioactive triterpenoids found in dandelion, a member of the family Asteraceae. In the animal or cellular models of several ailments, including liver damage, gastritis, colitis, arthritis, pneumonia, tumors, and immune system diseases, taraxasterol has been shown to have significant preventive and therapeutic effects. This review aims to evaluate the current state of research and provide an overview of the possible applications of taraxasterol in various diseases. The reported phytochemical properties and pharmacological actions of taraxasterol, including anti-inflammatory, anti-oxidative, and anti-carcinogenic properties, and its potential molecular mechanisms in developing these diseases are highlighted. Finally, we further explored whether taraxasterol has protective effects on neuronal death in neurodegenerative diseases. In addition, more animal and clinical studies are also required on the metabolism, bioavailability, and safety of taraxasterol to support its applications in pharmaceuticals and medicine.

The impact of physical conditions on the incidence of major depressive disorder in Chinese university students: Results from a longitudinal study

BACKGROUND

Major depressive disorder (MDD) is prevalent, and highly comorbid with physical illnesses. Few longitudinal studies have investigated the relationship between physical health conditions and MDD. The objectives of this study were to investigate the comorbid relationship between physical conditions and MDD, and the association between physical conditions and the 2-year risk of MDD.

METHODS

A study was conducted in first-year Chinese university students (n = 8,079) over two and half years, using a longitudinal design. An adapted version of the Composite International Diagnostic Interview (CIDI - 3.0) was used to assess for MDD. The presence of physician diagnosed physical conditions was assessed using ten self-report questions. Cross-sectional and longitudinal associations between self-reported physical conditions and MDD were estimated, adjusting for possible confounders.

RESULTS

The most frequently reported physical conditions were migraines, chronic rhinitis, and gastritis. We found that migraines, gastritis, and stomach ulcers were associated with a significantly higher lifetime prevalence of MDD than those without any physical health conditions. In those without a lifetime MDD, migraines, gastritis and stomach ulcers were also found to be significant predictors for 2-year risk of new onset MDD.

LIMITATIONS

Recall and selection biases are possible when using self-reporting measures. Additionally, the COVID-19 outbreak impacted the response rate at the second follow-up assessment. Lastly, the severity of the physical conditions was not measured.

CONCLUSIONS

Physical conditions and MDD are highly prevalent and comorbid in university students. Migraines, gastritis and stomach ulcers are associated with the risk of developing MDD. Future studies should further investigate how this information can be used to prevent MDD.

Gender Difference in Associations Between Telomere Length and Risk Factors in Patients With Stroke

Multiple risk factors of stroke are associated with telomere length shortening. Although leukocyte telomere length (LTL) is shorter in patients with stroke, the heterogeneity is high. Risk factors may be differentially associated with LTL in male and female patients contributing to the heterogeneity. However, the gender difference in associations between LTL and risk factors in stroke patients has not been investigated. In this study, we investigated the gender difference in associations between LTL and risk factors in 312 stroke patients. Real-time quantitative PCR was used to determine relative LTL, and multiple linear regression analysis was applied for association analyses. We found that LTL was negatively associated with triglyceride (TG) in all patients [β(95% CI) = −0.69 (−1.26, −0.11), P < 0.05] after adjusting confounders. Importantly, LTL was negatively associated with lack of exercise [β(95% CI) = −1.80 (−3.12, −0.49), P < 0.05] and LDL levels [β(95% CI) = −3.22 (−6.05, −0.390), P < 0.05] in male patients, while LTL was negatively associated with dyssomnia [β(95%CI) = −2.00 (−3.96, −0.07), P < 0.05] and diabetes [β(95%CI) = −2.13 (−4.10, −0.27), P < 0.01] in female patients. Our study showed that LTL is differently associated with risk factors in male and female patients with stroke, indicating that gender difference should be considered when LTL is potentially applied as an index of risk and prognosis for stroke. Our study also provides an insight into that gender differences should be considered when developing intervention strategies for stroke prevention and treatment.

RNA-sequencing of peripheral blood circular RNAs in Parkinson disease

BACKGROUND

Circular RNAs (circRNAs) play an important role in many neurological diseases and can serve as biomarkers for these diseases. However, the information about circRNAs in Parkinson disease (PD) remained limited. In this study, we aimed to determine the circRNAs expression profile in PD patients and discuss the significance of circRNAs in the diagnosis of PD.

METHODS AND RESULTS

Using RNA-sequencing in peripheral blood RNAs, we showed that a significant number of mRNAs or circRNAs were differentially expressed between PD patients and normal controls (NCs), which included 273 up-regulated and 493 down-regulated mRNAs, and 129 up-regulated and 282 down-regulated circRNAs, respectively. Functional analysis was performed using the Kyoto Encyclopedia of Gene and Genomes (KEGG) pathway analysis, and the results showed that the second most enriched KEGG pathway was PD. These data suggest that the levels of mRNAs and circRNAs in peripheral blood could be potentially used as biomarkers for PD. In addition, we correlated mRNAs and circRNAs by constructing a competing endogenous RNA (ceRNA) network in PD. The resulted-in ceRNA network included 10 differentially expressed mRNAs from PD pathway, 13 predicted miRNAs, and 10 differentially expressed circRNAs.

CONCLUSION

Collectively, we first characterized the expression profiles of circRNAs and mRNAs in peripheral blood from PD patients and proposed their possible characters in the pathogenesis of PD. These results provided valuable insights into the clues underlying the pathogenesis of PD.

The gene NtMYC2a acts as a 'master switch' in the regulation of JA-induced nicotine accumulation in tobacco

The biosynthesis and transport of nicotine has been shown to be coordinately upregulated by jasmonate (JA). MYC2, a member of basic helix-loop-helix (bHLH) transcription factor family, is well-documented as the core player in the JA signalling pathway to regulate diverse plant development processes. Four MYC2 genes were found in the tobacco genome, NtMYC2a/2b and 1a/1b. In this study, we tested whether one of them, NtMYC2a, acts as a 'master switch' in the regulation of nicotine biosynthesis and transport in tobacco. We generated NtMYC2a knockout tobacco plants using the CRISPR-Cas9 technique and analysed the effect of NtMYC2a knockout on expression of the nicotine biosynthesis genes (NtAO, NtQS, NtPMT1a, NtQPT2, NtODC2, NtMPO1, NtA622 and NtBBLa) and transport genes (NtMATE2 and NtJAT1), as well as leaf accumulation of nicotine in the NtMYC2a knockout plants. We found that all the nicotine biosynthesis and transport genes tested in this study were significantly downregulated (>50% reduction compared with wild-type control) in the NtMYC2a knockout plants. Moreover, the leaf nicotine content in knockout plants was dramatically reduced by ca 80% compared with the wild-type control. These results clearly show that NtMYC2a acts as a 'master switch' to coordinate JA-induced nicotine accumulation in tobacco and suggests that NtMYC2a might play an important role in tobacco nicotine-mediated defence against herbivory.

A Severe Diabetic Foot Ulcer With Intermediate Cuneiform Displacement and Multidrug-Resistant Pseudomonas aeruginosa Infection: A Rare Case Report

Diabetic foot ulcer (DFU) is considered as one of the most serious and prevailing complications of diabetes mellitus, while it is the major cause of amputations in diabetic patients. Herein, we reported an acquired severe traumatic DFU with an intermediate cuneiform hairline fracture and displacement in a 55-year old male (Grade IV of Wagner classification; Grade III of IWGDF classification). The Pseudomonas aeruginosa was identified in pus culture. Data of antibiotic susceptibility testing indicated that the isolates of Pseudomonas aeruginosa were multi-drug resistant. Routine debridement, clearing displaced intermediate cuneiform and drainage were performed to facilitate the outflow of pus and pressure mitigation. Dressing with Prontosan solution and gel was applied to the wound, and meropenem was systemically administrated in addition to effective glycemic control. The DFU has been fully healed after ~40-day treatment. For this case, clearing the displaced and fractured intermediate cuneiform is essential for the heal of the DFU in addition to the common strategy for DFU treatment, i.e., the combination of debridement, pressure mitigation, wound dressing with Prontosan, antibiotic selection and effective glycemic control. This case report might have value for the treatment of complex DFU with bone fracture and displacement, reducing the risk of amputation.

A Large Isolated Congenital Left Circumflex Artery-to-Right Atrial Fistula in a 9-Year-Old Child

Isolated congenital coronary artery fistula (ICCAF) is an exceedingly rare anomaly in which there is a direct abnormal connection between a coronary artery and other cardiac chambers or any of great vessels. The left circumflex artery (LCX) is the least common source of ICCAF. Here we reported a rare case of large ICCAF originated from the LCX in a 9-year-old boy. He presented fatigability, murmurs and NYHA class II. Echocardiography and cardiac CT revealed that an aneurysmal dilatation of the LCX along with the dilated coronary sinus entered into the right atrium (RA) through the great cardiac vein. However, it showed that the dilated LCX directly drained into the RA by coronary angiography, which was confirmed by the surgery. During the surgical procedure, the LCX fistula was identified in a 3^*3 cm bulbous structure, the aneurysmal dilation of RA tissue. The end of fistula was located in the lower-middle interatrial septum, which was near the coronary sinus and above the opening of inferior vena cava (IVC). Transcardiac chamber closure with cardiopulmonary bypass (CPB) was successfully performed for the correction of the fistula. It indicated that preoperative angiography is essential to define the details of large ICCAF with aneurysmal dilation. Moreover, transcardiac chamber closure with CPB is the optimal procedure for the treatment of large ICCAF, while interventional catheterization is not feasible due to the presence of aneurysmal dilation of the LCX. The description of this rare case might have great value for the diagnosis and treatment of large ICCAF originated from the LCX.

Proteasome Inhibition Activates Autophagy-Lysosome Pathway Associated With TFEB Dephosphorylation and Nuclear Translocation

Ubiquitin-proteasome pathway (UPS) and autophagy-lysosome pathway (ALP) are the two major protein degradation pathways, which are critical for proteostasis. Growing evidence indicates that proteasome inhibition-induced ALP activation is an adaptive response. Transcription Factor EB (TFEB) is a master regulator of ALP. However, the characteristics of TFEB and its role in proteasome inhibition-induced ALP activation are not fully investigated. Here we reported that the half-life of TFEB is around 13.5 h in neuronal-like cells, and TFEB is degraded through proteasome pathway in both neuronal-like and non-neuronal cells. Moreover, proteasome impairment not only promotes TFEB accumulation but also facilitates its dephosphorylation and nuclear translocation. In addition, proteasome inhibition-induced TFEB accumulation, dephosphorylation and nuclear translocation significantly increases the expression of a number of TFEB downstream genes involved in ALP activation, including microtubule-associated protein 1B light chain-3 (LC3), particularly LC3-II, cathepsin D and lysosomal-associated membrane protein 1 (LAMP1). Furthermore, we demonstrated that proteasome inhibition increases autophagosome biogenesis but not impairs autophagic flux. Our study advances the understanding of features of TFEB and indicates that TFEB might be a key mediator of proteasome impairment-induced ALP activation.

Operating behavior of micro-LEDs on a GaN substrate at ultrahigh injection current densities

Near-ultraviolet micro-LEDs with different diameters were fabricated on GaN substrates. The electroluminescence and the light output power-current density and current density-voltage relationships were measured. A saturated current density of 358 kA/cm² was achieved with a 20 µm LED. The ideality factor curves showed steps and peaks when the injection current density was increased from 20 to 150 kA/cm² and an abnormal efficiency increase. The transport and recombination processes of micro-LEDs at high injection current densities were simulated, and the many-body effect and phase space filling in the integrated quantum drift-diffusion model were considered. Serious current crowding was observed above 100 kA/cm², even for the 20 µm LED.

Telomere Length: A Potential Biomarker for the Risk and Prognosis of Stroke

Stroke is one of the leading causes of death and disability worldwide. Age is associated with increased risk of stroke, while telomere length shortening plays a pivotal role in the process of aging. Moreover, telomere length shortening is associated with many risk factors of stroke in addition to age. Accumulated evidence shows that short leukocyte telomere length is not only associated with stroke occurrence but also associated with post-stroke recovery in the elderly population. In this review, we aimed to summarize the association between leukocyte telomere length and stroke, and discuss that telomere length might serve as a potential biomarker to predict the risk and prognosis of stroke.

Detection of porcine circovirus-like virus P1 in Hebei, China

Porcine circovirus-like virus P1 is a novel unclassified circovirus that was first detected in China and may be associated with post-weaning multisystemic wasting syndrome (PMWS) and congenital tremor. In this study, we detected P1 infection in pigs in Hebei Province, China, in 2017. One hundred and forty of 500 (28.0%) serum samples from 25 pig farms with different PMWS status in seven cities were P1 positive on PCR. Twelve P1 strains were sequenced, and the complete genomes of 11 P1 strains were 648 nucleotides (nt) in length, whereas that of strain ZJK02 was 647 nt, with a G deletion at position of 183 in its genome. The complete genomic and capsid protein sequences of the 12 P1 strains analysed in this study shared 98.8%-100.0% and 86.5%-100.0% identity, respectively. A phylogenetic analysis based on the complete genomic and capsid sequences of 26 P1 strains showed that the 12 P1 sequences from Hebei Province clustered on two small branches. Further studies of the evolution and pathogenesis of P1 are required.

Long Non-Coding RNA: An Emerging Paradigm of Pancreatic Cancer

Pancreatic cancer remains a worldwide issue and burden that is hard to resolve given its low resection rate and chemo-resistance. Early diagnosis and early treatment are critical for conquering pancreatic cancer. Therefore, new biomarkers for diagnosis and prognosis are urgently needed. Previously, researchers mainly focused on protein-coding genetic and epigenetic changes in many types of cancers, and regarded the noncoding part as waste. Recently, however, long non-coding RNA (lncRNA) has emerged as a major participant in carcinogenesis, as it regulates cell proliferation, migration, invasion, metastasis, chemo-resistance, etc. The underlying mechanisms are summarized as signaling, decoy, guide and scaffold, yet the specific regulation networks remain to be uncovered. Several studies have revealed that some lncRNAs are dysregulated in pancreatic cancer, participating in biological functions. In this review, we will briefly outline the functional lncRNAs in pancreatic cancer, decipher possible mechanisms of lncRNAs, and further explore their significance in pancreatic cancer.

Annual direct medical costs associated with diabetes-related complications in the event year and in subsequent years in Hong Kong

AIM

To develop models to estimate the direct medical costs associated with diabetes-related complications in the event year and in subsequent years.

METHODS

The public direct medical costs associated with 13 diabetes-related complications were estimated among a cohort of 128 353 people with diabetes over 5 years. Private direct medical costs were estimated from a cross-sectional survey among 1825 people with diabetes. We used panel data regression with fixed effects to investigate the impact of each complication on direct medical costs in the event year and subsequent years, adjusting for age and co-existing complications.

RESULTS

The expected annual public direct medical cost for the baseline case was US$1,521 (95% CI 1,518 to 1,525) or a 65-year-old person with diabetes without complications. A new lower limb ulcer was associated with the biggest increase, with a multiplier of 9.38 (95% CI 8.49 to 10.37). New end-stage renal disease and stroke increased the annual medical cost by 5.23 (95% CI 4.70 to 5.82) and 5.94 (95% CI 5.79 to 6.10) times, respectively. History of acute myocardial infarction, congestive heart failure, stroke, end-stage renal disease and lower limb ulcer increased the cost by 2-3 times. The expected annual private direct medical cost of the baseline case was US$187 (95% CI 135 to 258) for a 65-year-old man without complications. Heart disease, stroke, sight-threatening diabetic retinopathy and end-stage renal disease increased the private medical costs by 1.5 to 2.5 times.

CONCLUSIONS

Wide variations in direct medical cost in event year and subsequent years across different major complications were observed. Input of these data would be essential for economic evaluations of diabetes management programmes.

Quantitative proteomics in A30P*A53T α-synuclein transgenic mice reveals upregulation of Sel1l

α-Synuclein is an abundantly expressed neuronal protein that is at the center of focus in understanding a group of neurodegenerative disorders called synucleinopathies, which are characterized by the intracellular presence of aggregated α-synuclein. However, the mechanism of α-synuclein biology in synucleinopathies pathogenesis is not fully understood. In this study, mice overexpressing human A30P*A53T α-synuclein were evaluated by a motor behavior test and count of TH-positive neurons, and then two-dimensional liquid chromatography-tandem mass spectrometry coupled with tandem mass tags (TMTs) labeling was employed to quantitatively identify the differentially expressed proteins of substantia nigra pars compacta (SNpc) tissue samples that were obtained from the α-synuclein transgenic mice and wild type controls. The number of SNpc dopaminergic neurons and the motor behavior were unchanged in A30P*A53T transgenic mice at the age of 6 months. Of the 4,715 proteins identified by proteomic techniques, 271 were differentially expressed, including 249 upregulated and 22 downregulated proteins. These alterations were primarily associated with mitochondrial dysfunction, oxidative stress, ubiquitin-proteasome system impairment, and endoplasmic reticulum (ER) stress. Some obviously changed proteins, which were validated by western blotting and immunofluorescence staining, including Sel1l and Sdhc, may be involved in the α-synuclein pathologies of synucleinopathies. A biological pathway analysis of common related proteins showed that the proteins were linked to a total of 31 KEGG pathways. Our findings suggest that these identified proteins may serve as novel therapeutic targets for synucleinopathies.

Experimental and observational studies find contrasting responses of soil nutrients to climate change

Manipulative experiments and observations along environmental gradients, the two most common approaches to evaluate the impacts of climate change on nutrient cycling, are generally assumed to produce similar results, but this assumption has rarely been tested. We did so by conducting a meta-analysis and found that soil nutrients responded differentially to drivers of climate change depending on the approach considered. Soil carbon, nitrogen, and phosphorus concentrations generally decreased with water addition in manipulative experiments but increased with annual precipitation along environmental gradients. Different patterns were also observed between warming experiments and temperature gradients. Our findings provide evidence of inconsistent results and suggest that manipulative experiments may be better predictors of the causal impacts of short-term (months to years) climate change on soil nutrients but environmental gradients may provide better information for long-term correlations (centuries to millennia) between these nutrients and climatic features. Ecosystem models should consequently incorporate both experimental and observational data to properly assess the impacts of climate change on nutrient cycling.

DOI:http://dx.doi.org/10.7554/eLife.23255.001

CDK5-Mediated Phosphorylation-Dependent Ubiquitination and Degradation of E3 Ubiquitin Ligases GP78 Accelerates Neuronal Death in Parkinson's Disease

The molecular mechanisms responsible for the loss of dopaminergic neurons in Parkinson's disease (PD) remain obscure. Loss of function of E3 ubiquitin ligases is associated with mitochondria dysfunction, dysfunction of protein degradation, and α-synuclein aggregation, which are major contributors to neurodegeneration in PD. Recent research has thus focused on E3 ubiquitin ligase glycoprotein 78 (GP78); however, the role of GP78 in PD pathogenesis remains unclear. Notably, cyclin-dependent kinase 5 (CDK5) controls multiple cellular events in postmitotic neurons, and CDK5 activity has been implicated in the pathogenesis of PD. Thus, we addressed the relationship between CDK5 and GP78 in MPTP-based PD models. We found that GP78 expression is decreased in MPTP-based cellular and animal PD models, and CDK5 directly phosphorylated GP78 at Ser516, which promoted the ubiquitination and degradation of GP78. Importantly, overexpression of GP78 or interference of GP78 Ser516 phosphorylation protected neurons against MPP⁺-induced cell death. Thus, our research reveals that the CDK5-GP78 pathway is involved in the pathogenesis of PD and could be a novel candidate drug target for the treatment of PD.

Expression signatures of long non-coding RNA in the substantia nigra of pre-symptomatic mouse model of Parkinson's disease

Parkinson's disease (PD) is an age-dependent neurodegenerative disease that can be caused by a variety of factors. Growing evidence shows that prior to the motor phase of PD can express molecular or imaging markers. Many long non-coding RNAs (lncRNAs) have been identified in neurodegenerative disease. However, the biogenesis and function of lncRNAs in the pre-symptomatic stage of PD is poorly understood. Here, we profiled the expression of lncRNAs and mRNAs in the substantia nigra pars compacta (SNpc) of pre-symptomatic mice over-expressing human A30P*A53T α-synuclein by microarray analysis. Based on the Pearson correlation analysis, lncRNA/mRNA co-expression network was constructed. GO enrichment and pathway analysis of lncRNAs-coexpressed mRNAs was conducted to identify the related biological function and pathologic pathways. Real-time PCR was used to detect the expression pattern of lncRNAs. Approximately 756 lncRNAs were aberrantly expressed in the SNpc of early over-expressing human A30P*A53T α-synuclein transgenic mice, including 477 downregulated lncRNAs and 279 upregulated lncRNAs. GO analysis indicated that these lncRNAs-coexpressed mRNAs were targeted to regulation of transcription (ontology: biological process), membrane (ontology: cellular component), and protein binding (ontology: molecular function). Pathway analysis indicated that lncRNAs-coexpressed mRNAs were mostly enriched in axon guidance signaling pathway. In conclusion, the present study firstly identified a series of novel early PD-associated lncRNAs caused by mutant α-synuclein. Further study the function of these aberrantly expressed lncRNAs may provide insight into treatment of early PD.

Parkinson-Related LRRK2 Mutation R1628P Enables Cdk5 Phosphorylation of LRRK2 and Upregulates Its Kinase Activity

Background

Recent studies have linked certain single nucleotide polymorphisms in the leucine-rich repeat kinase 2 (LRRK2) gene with Parkinson’s disease (PD). Among the mutations, LRRK2 c.4883G>C (R1628P) variant was identified to have a significant association with the risk of PD in ethnic Han-Chinese populations. But the molecular pathological mechanisms of R1628P mutation in PD is still unknown.

Principle Findings

Unlike other LRRK2 mutants in the Roc-COR-Kinase domain, the R1628P mutation didn’t alter the LRRK2 kinase activity and promote neuronal death directly. LRRK2 R1628P mutation increased the binding affinity of LRRK2 with Cyclin-dependent kinase 5 (Cdk5). Interestingly, R1628P mutation turned its adjacent amino acid residue S1627 on LRRK2 protein to a novel phosphorylation site of Cdk5, which could be defined as a typical type II (+) phosphorylation-related single nucleotide polymorphism. Importantly, we showed that the phosphorylation of S1627 by Cdk5 could activate the LRRK2 kinase, and neurons ectopically expressing R1628P displayed a higher sensitivity to 1-methyl-4-phenylpyridinium, a bioactive metabolite of environmental toxin MPTP, in a Cdk5-dependent manner.

Conclusion

Our data indicate that Parkinson-related LRRK2 mutation R1628P leads to Cdk5 phosphorylation of LRRK2 at S1627, which would upregulate the kinase activity of LRRK2 and consequently cause neuronal death.

Association between single-nucleotide polymorphisms of fatty acid synthase gene and meat quality traits in Datong Yak (Bos grunniens)

Fatty acid synthase (FASN) is a key enzyme in fatty acid anabolism that plays an important role in the fat deposit of eukaryotic cells. Therefore, in this study, we detected 2 novel single-nucleotide polymorphisms (SNPs) in the FASN gene in 313 adult individuals of Datong yak using polymerase chain reaction-single strand conformation polymorphism and DNA sequencing techniques. SNP g.5477C>T is located in intron 3 of FASN, and 3 genotypes, HH, HG, and GG, were detected in this mutation site. SNP g.16930T>A is located in exon 37 of FASN, and 2 genotypes, EE and EF, were detected in this site. Association analysis of these 2 SNPs with meat quality traits showed that in SNP g.5477C>T, yaks with the HH genotype and HG genotype had significantly higher intramuscular fat content than individuals with the GG genotype (P < 0.01). In SNP g.16930T>A, yaks with the EE genotype also had significantly higher IMF content than individuals with the EF genotype (P < 0.01). The results indicate that FASN may be used as a candidate gene affecting intramuscular fat content in Datong yaks.

Microfluidic laminate-based phantom for diffusion tensor-magnetic resonance imaging (DT-MRI)

This paper reports fabrication of a magnetic resonance imaging (MRI) phantom created by stacking of multiple thin polydimethylsiloxane (PDMS) layers. PDMS is spin coated on SU-8 molds to obtain the desired layer thickness and imprints of the microchannel patterns that define the phantom geometry. This paper also identifies the unique challenges related to the fabrication and assembly of multiple thin layers and reports for the first time assembly of a large number of thin laminates of this nature. Use of photolithography techniques allows us to create a wide range of phantom geometries. The target dimensions of the phantoms reported here are (i) a stack of 30 thin PDMS layers of 10 µm thickness (ii) curved 5 µm × 5 µm microchannels with 8.7 µm spacing, and (iii) straight 5 µm × 5 µm microchannels with 3.6 µm spacing. SEM scans of the assembled phantoms show open microchannels and a monolithic cross-section with no visible interface between PDMS layers. Based on the results of diffusion tensor magnetic resonance imaging (DT-MRI) scan, the anisotropic diffusion of water molecules due to the physical restriction of the microchannels was detected, which means that the phantom can be used to calibrate and optimize MRI instrumentation.

Involvement of the mitochondrial pathway in p53-independent apoptosis induced by p28GANK knockdown in Hep3B cells

It is well known that TP53 may mediate apoptosis triggered by anticancer drugs. However, accumulating evidence indicates that TP53 may be inactivated by mutations and/or deletions in about 50% of human cancers and, as such, may lead to pronounced resistance to therapeutic agents. Thus, the development of new approaches to improve the efficiency of therapeutic agents in cancer cells harboring mutant TP53 may have a significant impact on cancer treatment. It has been reported that knockdown by RNA interference (RNAi) of p28GANK (an alias of the gene PSMD10), a novel oncogene over-expressed in hepatocellular carcinoma (HCC), can induce apoptosis in HepG2, a TP53-intact HCC cell line. Because of the high frequency TP53 mutations in HCC, it is relevant to know whether p28GANK knockdown-induced apoptosis is also operational in TP53-negative HCC cells. Here, we investigated Adsip28GANK-induced apoptosis in the TP53-negative HCC cell line Hep3B. Our results indicate that p28GANK-knockdown induces the generation of reactive oxygen species (ROS), which in turn activates p38. Since p38 can signal to Bax, its activation may lead to mitochondrial transmembrane potential (Delta psi m) loss, cytochrome c release from mitochondria to cytosol, and caspase-9 activation, eventually triggering the mitochondrial pathway of apoptosis.

[Inhibiting gene expression in vivo by virus-mediated small interfering RNA]

Inhibiting gene expression in specific tissues and organs through intravenous injection would be the ultimately preferred method of disease therapy. Here, we report the successful delivery of lentivirus-mediated small interfering RNA (siRNA) to suppress the GFP gene expression in living mice. First, a lentiviral vector with siRNA (len-siRNA) driven by H1 promoter was constructed to suppress GFP expression effectively in Mel cells. When the len-siRNA virus was injected into transgenic mice, the GFP expression was significantly suppressed (over 15% reduction) in the recipient mice compared to the control mice and the suppressing effect lasted more than one week after injection. Our results demonstrate a new effective approach to inhibit gene expression by siRNA and lentiviral vectors. Further development of this suppression of gene expression siRNA drug should result in applications not only for cancers but also for infectious and immune diseases.

[Substitution of diphenyl sulfurine to trinuclear clusters and infrared spectra characterization]

Substitution of diphenyl sulfurine to dodecarbonyl-triruthenium and dodecarbonyl-triiron were studied respectively. Infrared spectra were used in characterization of the reactions and to follow the reaction processes from starting to finishing. Spectra data showed that the new compounds appeared and starting materials disappeared. The results products Ru3 (CO)9CSN2HPh2 and Fe3 (CO)8S2CNPh were taken in KBr pellet infrared spectras. C, S and N in diphenyl sulfurine might coordinate to transitionmetal atoms in the clusters. Since trinuclear ruthenium and iron clusters have different stability and diphenyl sulfurine induced attacked to cluster skeleton in reaction, Ru3 (CO)12 and Fe3 (CO)12 give different coordination structure trinuclear Ru and Fe clusters, in which every metal atom forms 18 e constitution.

[Study in coordination substitution of trinuclear iron and ruthenium clusters by infrared and ultraviolet spectroscopy]

In this paper, ultraviolet spectra and infrared spectra were used in the characterization of the reaction in which carbonyls in trinuclear-iron cluster and trinuclear-ruthenium cluster were substituted by Ph2C2 and PPh3 respectively. The spectra showed the process of the new compounds appear and starting materials disappear separately. Infrared spectra data in KBr pellets further proved the result products. Reaction of Ru3(CO)12 with PPh3 (mol ratio = 1:3) in hexane affords Ru3(CO)9 (PPh3)3, a red microcrystalline solid and Fe3(CO)12 with Ph2C2 (mol ratio = 1:1) affords Fe3(CO)10 (Ph2C2) a deep green crystals. In the study, the ultraviolet spectra and infrared spectra of reaction solutions changed following the reactions, given a information in which we known the reaction starting and finishing. Then new compounds possibly were separated from reaction solutions. This is an important method used for synthesis and catalysis.

Epidemiologic and clinical characteristics of Kawasaki disease in Shaanxi Province, China, 1993-1997

The objective of this paper is to describe the epidemiological and clinical characteristics of Kawasaki disease (KD) in Shaanxi Province, China during the 5-year period from January 1993 to December 1997. A province-wide epidemiological survey on KD was made by the China-Japan Kawasaki Disease Study Group. The questionnaire form and the diagnostic criteria of KD, which were prepared by the Japan Kawasaki Disease Research Committee and translated into Chinese, were sent to the departments of pediatrics of all the hospitals with 100 beds or more in Shaanxi province. All the KD patients who were diagnosed during the observation period from 1993 to 1997 were asked to take part in this survey. The databases of reported KD in this survey were analysed at the Department of Pediatrics of the Shaanxi Provincial People's Hospital, Xi'an, China. All the patients that satisfied the diagnostic criteria were included in the report. A total of 105 (70 per cent) hospitals responded and 376 cases of KD were confirmed. More cases were reported in 1993 and 1994. Of the total patients reported, 69 per cent were children under 3 years old with a male to female ratio of 1.6:1. The proportion of patients with cardiac sequelae was 19 per cent with a male to female ratio of 3:1. There were four fatal cases with a fatality rate of 1 per cent. It is concluded that KD is common in China. Continuous surveillance is necessary to maintain high awareness of KD so as to find possible risk factors and their association with the disease.

[A clinical and epidemiological study of 86 cases on abused children]

OBJECTIVE

To study the clinical and epidemiological manifestations on abused children, in order to find ways of prevention.

METHODS

Retrospective study was carried out clinically and epidemiologically on 86 cases abused children from 1998.1 - 1999.12.

RESULTS

The sex ratio (male:female) in the abused children was 0.76:1. Most cases were 3 - 16 years olds. Abuse incidences were most commonly occurred in spring and winter, accounted for 32.56% and 33.72% respectively. Most abuses happened physically (45.34%), predominantly involved skin (30.23%) and parenchyma (11.27%). Mental abuse accounted for 24.41%. 14 cases resulted in death (16.27%). 55 (64%) of the abusers were illiterate or with poor education.

CONCLUSION

The abused sites mostly involved skin and parenchyma, but also caused harm to children's mental health, even causing deaths. Most abused children were female and abusers had lower cultural background. Thus, we need to provide a sounding board, to work on child abuse preventin.

[Epidemiological and clinical characteristics of Kawasaki disease in Shanxi province]

OBJECTIVE

The objective of this paper is to describe the epidemiological and clinical characteristics of Kawasaki disease (KD) in Shanxi province, China during a 5 year - period from January 1993 to December 1997.

METHODS

A province - wide epidemiological survey on Kawasaki disease (KD) was carried ont by the China - Japan Kawasaki disease study group. The questionnaire form and the diagnostic criteria of KD which was prepared by the Japan Kawasaki disease research committee and translated into Chinese were sent of the departments of pediatrics of all the hospitals with 100 or more beds in Shanxi province. All the KD patients who were diagnosed during the observation period from 1993 to 1997 were asked to report to this survey. The database of reported KD in this survey was analyzed at the Department of pediatrics of the Shanxi provincial people's hospital, Xian, China. All the patients that satisfied the diagnostic criteria were included.

RESULTS

A total of 105 (70%) hospitals responded and 376 cases of KD were confirmed. More cases were reported in 1993 and 1994. Of the total patients reported, 69% were children under 3 years old with male to female ratio of 1.6:1. The proportion of patients with cardiac sequelae was 19% with male to female ratio: 3:1. There were 4 fatal cases with a fatality rate of 1%.

CONCLUSIONS

Since KD is common in China continuous surveillance is necessary to maintain high awareness of KD so as to identify possible risk factors and its association with other disease.