Successful treatment of thalidomide for recurrent bleeding due to gastric angiodysplasia in hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disorder, which is uncommon anomaly to recurrent gastrointestinal bleeding. Although there are several forms of therapy ranging from local therapy to operations or drug therapy, there is a lack of more effective treatment for the disease. In this report, we presented a Chinese patient with recurrent melena due to gastric angiodysplasia in HHT treated successfully with thalidomide.

Generating ultrabroadband terahertz radiation based on the under-compression mode of velocity bunching

We propose and analyze a scheme to generate enhanced ultrabroadband terahertz (THz) radiation through coherent transition radiation emitted by ultrashort electron beams based on a 10.5 m beamline at Tsinghua University. The proposed scheme involves the initial compression of the electron beam with a few hundred pC charges using a velocity bunching scheme (i.e., RF compression) in an under-compression mode instead of the usual critical-compression mode in order to maintain a positive energy chirp at the exit of the traveling wave accelerator. After a long drift segment, the particles in the tail catch up with the bunch head. More than 80% of the particles are distributed in a spike with an rms length less than 20 fs. Such beams correspond to an ultrabroadband coherent transition radiation (CTR) spectrum of 0.1 THz to 25 THz, with the single-pulse THz radiation energy of up to 50 μJ. The principle of CTR and under-compression mode of velocity bunching are introduced in this paper. And the ASTRA simulation parameters and the stability of the system are also discussed.

A dairy fat matrix providing alpha-linolenic acid (ALA) is better than a vegetable fat mixture to increase brain DHA accretion in young rats

Achieving an appropriate DHA status in the neonatal brain is an important goal of neonatal nutrition. We evaluated how alpha-linolenic acid (ALA), provided for six weeks after weaning by different dietary fat matrix, improved brain DHA content of young male rats born from deficient-dams. The level of ALA achieved was based on the fat composition of usual infant vegetable formula. A palm oil-blend diet thus providing 1.5%ALA was compared to dairy fat-blend-based diets that provided either 1.5%ALA or 2.3%ALA, or a rapeseed oil diet providing 8.3%ALA (n-6/n-3 ratio were, respectively 10,10,5,2.5). The 1.5%ALA-dairy-fat-blend was superior to 1.5%ALA-palm-oil-blend to restore values of brain DHA, while the 2.3%ALA-dairy-fat-blend exhibited a further increase and reached the values obtained with pure rapeseed diet (8.3%ALA). Dairy-fat-blends enriched with ALA appear to be an interesting strategy for achieving optimal DHA levels in the brain of post-weaning rats. Providing dairy fat as well as a reduction of the LA/ALA ratio should be reconsidered to design infant formula.

Mouse hypothalamic GT1-7 cells demonstrate AMPK-dependent intrinsic glucose-sensing behaviour

AIMS/HYPOTHESIS

Hypothalamic glucose-excited (GE) neurons contribute to whole-body glucose homeostasis and participate in the detection of hypoglycaemia. This system appears defective in type 1 diabetes, in which hypoglycaemia commonly occurs. Unfortunately, it is at present unclear which molecular components required for glucose sensing are produced in individual neurons and how these are functionally linked. We used the GT1-7 mouse hypothalamic cell line to address these issues.

METHODS

Electrophysiological recordings, coupled with measurements of gene expression and protein levels and activity, were made from unmodified GT1-7 cells and cells in which AMP-activated protein kinase (AMPK) catalytic subunit gene expression and activity were reduced.

RESULTS

Hypothalamic GT1-7 neurons express the genes encoding glucokinase and ATP-sensitive K(+) channel (K(ATP)) subunits K ( ir ) 6.2 and Sur1 and exhibit GE-type glucose-sensing behaviour. Lowered extracellular glucose concentration hyperpolarised the cells in a concentration-dependent manner, an outcome that was reversed by tolbutamide. Inhibition of glucose uptake or metabolism hyperpolarised cells, showing that energy metabolism is required to maintain their resting membrane potential. Short hairpin (sh)RNA directed to Ampkα2 (also known as Prkaa2) reduced GT1-7 cell AMPKα2, but not AMPKα1, activity and lowered the threshold for hypoglycaemia-induced hyperpolarisation. shAmpkα1 (also known as Prkaa1) had no effect on glucose-sensing or AMPKα2 activity. Decreased uncoupling protein 2 (Ucp2) mRNA was detected in AMPKα2-reduced cells, suggesting that AMPKα2 regulates UCP2 levels.

CONCLUSIONS/INTERPRETATION

We have demonstrated that GT1-7 cells closely mimic GE neuron glucose-sensing behaviour, and reducing AMPKα2 blunts their responsiveness to hypoglycaemic challenge, possibly by altering UCP2 activity. These results show that suppression of AMPKα2 activity inhibits normal glucose-sensing behaviour and may contribute to defective detection of hypoglycaemia.

The dynamic change of circulating tumour cells in patients with operable breast cancer before and after chemotherapy based on a multimarker QPCR platform

Background:

The possible presence of early tumour dissemination is the rationale behind the use of systemic adjuvant chemotherapy in patients with operable breast cancer. Circulating tumour cells (CTC) in peripheral blood may represent the possible presence of early tumour dissemination. However, relatively few studies were designed to investigate the relationship between the change of CTC status and the efficacy of adjuvant chemotherapy in operable breast cancer patients.

Methods:

In a prospective study, we established a multimarker real-time quantitative PCR platform to detect CTC in peripheral blood of breast cancer patients. By using this platform, we detected CTC in peripheral blood of 94 operable breast cancer patients. Control group consisted of 20 patients with benign breast disease and 20 healthy volunteers. For 72 patients who underwent systemic adjuvant chemotherapy, the dynamic CTC status at three different time points (1 day before initiation of chemotherapy, 1 week after three cycles of chemotherapy and 1 week after all cycles of chemotherapy) was observed.

Results:

Circulating tumour cells were detected in 56% (53 out of 94) of patients with operable breast cancer. The specificity was 95%. Seventy-two patients who received systemic adjuvant chemotherapy were followed up. After three cycles of chemotherapy, 47% (18 out of 38) of patients who were CTC-positive before chemotherapy changed into negative status. In addition, another 5% (2 out of 38) of patients had changed into negative status after all cycles of chemotherapy.

Conclusion:

Systemic adjuvant chemotherapy had a significant impact on CTC status, and this effect could be observed after three cycles of chemotherapy. Circulating tumour cells detection had the potential to be used to evaluate the efficacy of systemic adjuvant chemotherapy immediately after the chemotherapy was finished in operable breast cancer patients.

Genetic variation in CXCL12 and risk of cervical carcinoma: a population-based case-control study

CXCL12 provides a chemotactic signal-directing leucocyte migration and regulates metastatic behaviour of tumour cells. We conducted a population-based case-control study to test the hypothesis that common genetic variation in CXCL12 individual single nucleotide polymorphism (SNP) alleles and haplotypes] is associated with the risk of cervical carcinoma. Cases (n = 917) were residents of western Washington State diagnosed with invasive squamous cell cervical carcinoma (SCC), invasive adenocarcinoma or adenosquamous carcinoma, or adenocarcinoma in situ of the cervix. Control participants (n = 849) were identified from the source population by random digit telephone dialling and frequency matched to cases on county and age. Nine CXCL12 tagSNPs chosen from the SeattleSNPs database were genotyped. The minor allele of intronic SNP rs266085 was inversely associated with cervical cancer under a recessive genetic effects model (OR = 0.74, 95% CI: 0.56-0.98). Among the ten common haplotypes inferred from the nine tagSNPs, one haplotype defined by minor alleles at 5'-flanking SNP rs17885289 and rs266085, and common alleles at the other seven SNPs occurred among 7.8% of cases and 10.6% of controls (dominant model OR = 0.72, 95% CI: 0.56-0.93; recessive model OR = 0.35, 95% CI: 0.12-0.97; and log-additive model OR = 0.72, 95% CI: 0.57-0.90). A stepwise procedure identified rs17885289, rs266085 and 3'-untranslated region (UTR) SNP rs266093 as the most parsimonious subset of SNPs necessary to define the haplotype inversely associated with cervical cancer risk in our study. A 3'-UTR SNP, rs1801157, previously found to be related to HIV pathogenesis, was not associated with cervical cancer risk. Further population-based studies are warranted to confirm these associations between genetic variation in CXCL12 and cervical cancer risk.

A non-uniform expansion mechanical safety model of the stent

Stents have a serial unstable structure that readily leads to non-uniform expansion. Non-uniform expansion in turn creates a stent safety problem. We explain how a stent may be simplified to a serial unstable structure, and present a method to calculate the non-uniform expansion of the stent on the basis of the serial unstable structure. We propose a safety criterion based on the expansion displacement instead of the strain, and explain that the parameter Rd, the ratio of the maximum displacement of the elements to normal displacement, is meaningful to assess the safety level of the stent. We also examine how laser cutting influences non-uniform expansion. The examples illustrate how to calculate the parameter Rd to assess non-uniform expansion of the stent, and demonstrate how the laser cutting offset and strengthening coefficient of the material influence the stent expansion behaviour. The methods are valuable for assessing stent safety due to non-uniform expansion.

RNA interference-mediated silencing of the polo-like kinase 1 gene enhances chemosensitivity to gemcitabine in pancreatic adenocarcinoma cells

Gemcitabine is the first-line chemotherapeutic agent for advanced adenocarcinoma of the pancreas; however, chemoresistance to gemcitabine remains a major cause of failure for the clinical treatment of this disease. Polo-like kinase 1 (Plk-1) is highly expressed in pancreatic cancer cell lines and pancreatic tumour tissues, and is involved in a wide variety of cell cycle processes. Nevertheless, its biological role and implication for gemcitabine resistance are not clearly defined. In this study, we used RNA-interference (RNAi)-mediated depletion of Plk-1 to determine its potential for sensitizing pancreatic tumour cells to gemcitabine. We showed that the level of Plk-1 protein was correlated significantly with gemcitabine resistance in human pancreatic adenocarcinoma cells and that overexpression of Plk-1 reduced sensitivity to gemcitabine in these cells. In addition, small interfering RNA (siRNA)-mediated knockdown of Plk-1 caused cell cycle arrest at G2/M and the reduction of cellular proliferation. More importantly, the treatment of pancreatic cancer cells with Plk-1 siRNA followed by exposure to gemcitabine dramatically decreased cell viability and increased cellular apoptosis, as compared with treatment with either agent alone. These observations indicate that down-regulation of Plk-1 expression by RNAi enhances gemcitabine sensitivity and increases gemcitabine cytotoxicity in pancreatic tumour cells. This is the first demonstration that the combination of Plk-1 gene therapy and gemcitabine chemotherapy has synergistic anti-tumour activity against pancreatic carcinoma in vitro. This combination treatment warrants further investigation as an effective therapeutic regimen for patients with resistant pancreatic cancer and other tumours.

Detection of betanodavirus in juvenile barramundi, Lates calcarifer (Bloch), by antigen capture ELISA

Betanodavirus infection of fish has been responsible for mass mortalities in aquaculture hatcheries worldwide. Betanodaviruses possess a bipartite single-stranded RNA genome consisting of the 3.1 kb RNA1 encoding an RNA-dependent RNA polymerase and the B2 protein, while the 1.4 kb RNA2 encodes the viral nucleocapsid protein, alpha. A panel of six monoclonal antibodies against the alpha protein of greasy grouper nervous necrosis virus (GGNNV) was developed for use in diagnostics. All antibodies reacted with native and recombinant alpha in immunoblot and indirect immunofluorescence assays. Each of the monoclonal antibodies reacted against discrete regions of the alpha protein, though none reacted with the extreme C-terminal region of the protein. One of the monoclonal antibodies, specific for the K151-T246 region of alpha, was used for the development of an antigen capture ELISA. In this assay we could detect 10(3)-10(4) TCID(50) units of virus derived from infected tissue culture supernatants. Head tissue extracts prepared from experimentally infected barramundi, Lates calcarifer, juveniles were assayed for GGNNV using the antigen capture assay and a clear increase in alpha antigen was detected from 5 to 15 days post-challenge. The assay thus represents a useful method for field-based detection of betanodavirus in fish hatcheries.

Di-2-ethylhexyl phthalate in the fruits ofBenincasa hispida

Di-2-ethylhexyl phthalate (DEHP) is a commonly used plasticizer that is harmful to human health. magnetic resonance spectroscopy from the edible fruit flesh of Benincasa hispida (wax gourd) of the plant family Curcurbitaceae. The DEHP content of seven wax gourd samples collected from southern and northern provinces in China was determined as (mean +/- SD): 18.3 +/- 0.43, 2.64 +/- 0.44, 44.0 +/- 0.34, 62.5 +/- 0.48, 52.0 +/- 0.42, 58.3 +/- 0.55 and 75.5 +/- 0.63 mg kg-1 fresh weight, respectively, indicating that most wax gourds were severely contaminated with DEHP.

Regulation of PUMA-alpha by p53 in cisplatin-induced renal cell apoptosis

Nephrotoxicity is a major side effect of cisplatin, a widely used cancer therapy drug. Depending on its concentration, cisplatin induces necrosis or apoptosis of tubular cells in the kidneys, whereas the underlying injury mechanism is unclear. Our recent work has suggested a critical role for p53 in cisplatin-induced tubular cell apoptosis; nevertheless, the apoptotic events triggered by p53 remain elusive. The current study has examined Bcl-2 family proteins, critical regulators of apoptosis that may be subjected to p53 regulation. Following cisplatin treatment, the expression of Bcl-xL, an antiapoptotic molecule, was suppressed, while the expression of Bak, a proapoptotic molecule, increased slightly. Of interest, PUMA-alpha, a newly identified p53-responsive proapoptotic Bcl-2 family protein, was drastically induced by cisplatin. PUMA-alpha induction preceded or paralleled the development of apoptosis. Induced PUMA-alpha was localized in mitochondria and appeared to antagonize Bcl-xL via molecular interaction. PUMA-alpha induction during cisplatin treatment was attenuated by pifithrin-alpha, a pharmacological inhibitor of p53, which was accompanied by the amelioration of Bax activation, cytochrome c release and apoptosis. Moreover, PUMA-alpha induction was suppressed by dominant-negative p53. Importantly, cisplatin-induced apoptosis was ameliorated in PUMA-alpha knockout cells. In vivo, cisplatin induced PUMA-alpha in the kidneys, and the inductive response was abrogated in p53-deficient animals. Together, this study has demonstrated the first compelling evidence for the involvement of PUMA-alpha in p53-mediated renal cell apoptosis during cisplatin nephrotoxicity.