Recoil polarization measurements of the proton electromagnetic form factor ratio to Q2 = 8.5 GeV2

Among the most fundamental observables of nucleon structure, electromagnetic form factors are a crucial benchmark for modern calculations describing the strong interaction dynamics of the nucleon's quark constituents; indeed, recent proton data have attracted intense theoretical interest. In this Letter, we report new measurements of the proton electromagnetic form factor ratio using the recoil polarization method, at momentum transfers Q2=5.2, 6.7, and 8.5  GeV2. By extending the range of Q2 for which G(E)(p) is accurately determined by more than 50%, these measurements will provide significant constraints on models of nucleon structure in the nonperturbative regime.

Activation of Akt and MAPK pathways enhances the tumorigenicity of CD133+ primary colon cancer cells

Cancer stem cells (CSCs) play an important role in carcinogenesis, resistance to treatment and may lead to cancer recurrence and metastasis. However, the molecular mechanism of CSC involved in these events needs to be further elucidated. In this study, CD133(+) colon cancer cells were cultured, which showed CSC properties both in vitro and in vivo from metastatic tissue. Upstream molecules in Akt and mitogen-activated protein kinase (MAPK) pathways were preferentially expressed in these CD133(+) cells, as revealed by a global gene chip. The kinase activities of Akt and extracellular signal-regulated kinase (Erk)1/2 were also significantly upregulated in CD133(+) cells. In addition, the clonogenic growth of CD133(+) cell was reduced greatly by inhibiting the activity of Akt and Erk1/2. The results revealed the Akt and MAPK pathways were involved in the tumorigenesis of CD133(+) colon cancer cells, suggesting that molecules in these two pathways might be potential targets in the future therapy.

Quick and effective technique for specimen extraction during video-assisted thoracic surgery

We describe here a novel technique for specimen extraction during video-assisted thoracic surgery. Traditionally, most surgeons extract specimens using a tough nylon sac or bag. However, this procedure is time-consuming and difficult for trainees to perform. We developed a novel extraction sac with two positioning finger sacs. Our technique consists of first grasping the specimen and then enclosing it with the sac instead of placing the specimen into the sac. By grasping the specimen and performing a movement resembling the drawing off of a glove, the resected specimen is inserted into the bag and can be subsequently extracted. We conclude that this new strategy is an effective, quick and safe technique.

Association of genetic variants in the apelin-APJ system and ACE2 with blood pressure responses to potassium supplementation: the GenSalt study

BACKGROUND

Genetic factors may influence blood pressure (BP) responses to dietary potassium intake. We examined the association of genetic variants in the apelin-APJ system and angiotensin-converting enzyme 2 (ACE2) with BP responses to potassium supplementation.

METHODS

We conducted a 7-day potassium supplementation (60 mmol/day) intervention among 1,906 Chinese adults who participated in the Genetic Epidemiology Network of Salt-Sensitivity (GenSalt) study. Tag single-nucleotide polymorphisms (SNPs) based on HapMap data and potential functional SNPs were selected in the APLN, APLNR, and ACE2 genes. Because the ACE2 and APLN genes are located on the X chromosome, men and women were analyzed separately.

RESULTS

In women, SNP rs2235306 in the APLN gene was significantly associated with diastolic BP (DBP) response to potassium supplementation (P = 0.0009). The DBP responses (95% confidence interval (CI)) among those with genotypes T/T, T/C, and C/C were -2.22 (-2.74, -1.70), -1.69 (-2.20, -1.19), and -0.81 (-1.54, -0.09) mm Hg, respectively. In men, SNP rs4646174 of the ACE2 gene was significantly associated with systolic BP (SBP), DBP, and mean arterial pressure (MAP) responses to potassium supplementation (P = 0.0001, P = 0.001, and P = 3.0 x 10(-6), respectively). The SBP, DBP, and MAP responses (95% CI) were -0.79 (-2.27, 0.69) vs. -3.53 (-3.94, -3.12), 1.07 (-0.34, 2.49) vs. -1.06 (-1.43, -0.69), and 0.44 (-0.60, 1.48) vs. -1.89 (-2.22, -1.55) mm Hg among men with minor G allele compared to those with major C allele of rs4646174, respectively.

CONCLUSION

Our study indicates that genetic variation of APLN and ACE2 may influence BP response to potassium intake.

Distribution of radionuclides in the guano sediments of Xisha Islands, South China Sea and its implication

Several natural and anthropogenic radionuclides ((210)Pb, (226)Ra and (137)Cs) in guano-phosphatic coral sediments and pure guano particles collected from Ganquan, Guangjin, Jinqing and Jinyin Islands of the Xisha archipelago, South China Sea, were analyzed. The Constant Initial Concentration (CIC) model and the Constant Rate of Supply (CRS) model were applied for age calculation. The average supply rate of (210)Pb was 126 Bq m(-2) a(-1), very close to the flux of northern hemisphere average (125 Bq m(-2) a(-1)). The activities of anthropogenic radionuclides in the sediments were very low, indicating that human nuclear tests did not notably impact this region. The main source of radionuclides in the sediments was from atmospheric precipitation, and the organic matter derived from plant and produced by nutrient-rich guano could further enhance them.

Activation of GABAergic neurons following tooth pulp stimulation

The functional impact of GABA (gamma-aminobutyric acid)ergic neurons in nociceptive transmission of the spinal trigeminal nucleus is not fully established. Using both the glutamic acid decarboxylase (GAD)(67)-green fluorescence protein (GFP) knock-in mouse and the tooth pulp stimulation model, we performed double-immunofluorescent histochemistry to determine the characteristics of GABAergic neuron activation in the spinal trigeminal nucleus. The number of Fos-positive GABAergic neuronal profiles was significantly increased 2 hrs after tooth pulp stimulation. The Fos/GFP double-labeled neurons were mainly present in superficial laminae of the spinal trigeminal subnucleus interpolaris-caudalis transition (Vi/Vc) and subnucleus caudalis (Vc) on the side ipsilateral to the stimulation. Subsequently, the number of double-labeled neurons decreased gradually and became comparable with that of the controls by 48 hrs. Our results provide direct morphological evidence that a subset of GABAergic neurons in the spinal trigeminal system was activated during tooth pulp stimulation.

The role of surface wettability and surface charge of electrosprayed nanoapatites on the behaviour of osteoblasts

A new deposition method is presented, based on electrospraying, that can build bioceramic structures with desirable surface properties. This technology allows nanoapatite crystals, including hydroxyapatite (nHA), carbonate-substituted HA (nCHA) and silicon-substituted HA (nSiHA), to be electrosprayed on glass substrates. Human osteoblast cells cultured on nSiHA showed enhanced cell attachment, proliferation and protein expression, namely alkaline phosphatase, type 1 collagen and osteocalcin, as compared to nHA and nCHA. The modification of nanoapatite by the addition of silicon into the HA lattice structure renders the electrosprayed surface more hydrophilic and electronegatively charged.

BCL10 as a new candidate gene for immune response in pigs: cloning, expression and association analysis

BCL10 is an apoptotic regulatory molecule identified through its direct involvement in t(1; 14)(p22; q32) of mucosa-associated lymphoid tissue lymphoma, and was implicated in the pathogenesis of this and several other tumour types. BCL10 was recognized as an antigen receptor-specific regulator of NF-kappaB, which showed close association with immune responses. In this study, we cloned and characterized BCL10 from the porcine spleen and analysed its genomic structure. BCL10 was mapped to SSC4q21-q23 by the IMpRH panels, it is closely linked to the marker S0161 and SW1461. This gene has three exons and two introns. Reverse transcriptase-polymerase chain reaction analyses showed that BCL10 was widely expressed in all the examined tissues. Transient transfection indicated that porcine BCL10 was located in cytoplasm in Pig Kidney Epithelial cells. BCL10 gene displays the opposite expression trend between the two treatments mimic virus and bacteria of polyriboinosinic-polyribocytidylic acid (Poly I:C) and lipopolysaccharide (LPS). The level of the BCL10 mRNA was up-regulated during 12-24 h and peaking at 48 h when treated with LPS, whereas it was down-regulated during 0-48 h and highest at 0 h (cells without treating with Poly I:C) when treated with Poly I:C. One single nucleotide polymorphism (SNP) site was identified in the 3'-untranslated region of porcine BCL10. Association analysis revealed that this SNP was significantly associated with intermediate cell mass (eosinophile granulocyte, basophile granulocyte and histoleucocyte) percentage, absolute intermediate cell mass count and mean red blood cell volume of 0-day-old pigs, and red blood cell count of 17-day-old pigs (P < 0.05), and also had significant associations with red blood cell count and haemoglobin concentration of 32-day-old pigs (P < 0.01).

Novel Stably Transplantable Xenograft Models of Human Breast Cancer for Evaluation of Experimental Therapeutics

In translational breast cancer research, our ability to evaluate clinical responses of human tumors to new therapeutic agents is severely limited experimentally. For example, it is not possible to evaluate the response of a single tumor to multiple candidate therapeutic agents. Conversely, the limited number of well-characterized in vivo preclinical human tumor models currently available precludes evaluation of multiple clinically relevant tumors with candidate therapeutic agents. These limitations severely impinge on our ability to develop and test novel therapeutic agents, particularly those that may target tumor-initiating “cancer stem cells”, which are relatively resistant to chemotherapy and radiation and may be responsible for disease recurrence and metastases.Historically, in vivo experimental therapeutic research has relied on either genetically engineered animal models, or “xenograft” transplantation models in which established human cancer cell lines are transplanted into immunocompromised host mice. However, each type of model has significant limitations. We sought to circumvent some of these limitations by propagating a cohort of human tumors as stably transplantable xenograft tissue lines grown in the absence of engineered or immortalized fibroblasts by transplanting clinical biopsies directly into the mammary fat pad of SCID/Beige immunocompromised mice (lacking B-cell, T-cell, and NK cell function) without intervening culture in vitro.Thus far, we have established 13 independent stably transplantable xenograft lines representing nine “triple-negative” (ER-PR-HER2-), two HER2+, and two ER+ breast cancers. Established xenograft lines show phenotypic similarity to the primary tumor with respect to histology and gene expression. Xenografts are being characterized genetically by whole genome sequencing as well as for the diversity of tumor-initiating cell types present. These models are proving useful for the evaluation of experimental therapeutics for their ability to inhibit tumor growth, and for their ability to target the subset cancer cells capable of regenerating tumors upon transplantation, with the goals of overcoming chemoresistance, preventing disease recurrence, and eliminating metastases.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1159.

Comparison of Synchrotron Images of DCIS of the Breast with Their Pathologic Findings

Background: Synchrotron radiation x-ray imaging have opened a new door to explore breast tissue below the micron scale providing detailed internal structures of the samples with a great magnification and an excellent resolution. Using phase contrast technique, we got monochromated synchrotron images of DCIS (Ductal Carcinoma In Situ) of the breast tissue section. To figure out relation with their optical microscopic features, we compared the synchrotron images of the DCIS with their histopathologic findings of the same stained section.Material and Methods: A x-ray microscope was installed on 1B2 beamline of Pohang Light Source, a third generation synchrotron radiation facility with operating energy of 2.5 GeV in Pohang, Korea. The x-ray energy was set at 11.1 keV, and the x-ray beam was monochromatized by a W/B4C monochromator. Zernike phase-shifter was adapted for phase contrast x-ray microscopy. Formalin-fixed 5µm-thick breast tissue sample was attached onto the Kapton film, and positioned 25 m away from the beam source. The synchrotron image of sample was converted into a visual image on the CsI(TI) scintillation crystal, and this visual image was captured by a full frame CCD camera. After scanning, we patched these images one and another to show the large area of the tissue section. For the comparative analysis with their synchrotron image, synchrotron-scanned breast tissue sections were stained, and the histopathologic findings of the samples were captured by image analyzer. The magnifying power of this microscope was 100x.Results: The monochromated x-ray microscopic images of DCIS of the breast tissue were obtained with a good resolution. These images revealed various structures of DCIS lesion with a good contrast and high visibility by phase contrast technique. They include prominent and intact periductal basement membrane - a hallmark of DCIS lesion, and stippled fine microcalcifications which were indistinct in the histologic section, and a shadow of intense peritumoral inflammatory cell infiltration. But the minute changes of each cancer cell showing the features of cancer tissue such as, cellular differentiation and nuclear grade, were not identified well.Discussion: The x-ray microscopic imaging of DCIS of the breast tissue section with synchrotron radiation showed a good correspondence with the histopathologic findings of their stained tissue sections. And the synchrotron image of DCIS had some unique radiologic features differentiating from histopathogic findings. Therefore the synchrotron images of the DCIS lesion appear to have a new possibility of use for the clinical and research purposes in near future.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5015.