In vivo induction and delivery of nerve growth factor, using HEK-293 cells

Tissue-engineering strategies offer hope to patients facing functional impairment after nerve injury. We have previously demonstrated that HEK-293 cells can release nerve growth factor (NGF) in vitro, using an inducible system of expression. In this study, our objective was to assess the efficacy of the NGF delivery system in vivo, using nude rats. HEK-293 cells were transfected with human NGF cDNA. Ponasterone A (PonA) was used as the inducing agent. NGF collection chambers were implanted subcutaneously in nude rats. Sealed chambers were filled with one of the following: (1) DMEM, (2) untransfected 293 cells (EcR-293) plus PonA, (3) untransfected EcR-293 without PonA, (4) transfected 293 cells (hNGF-EcR-293) plus PonA, or (5) transfected hNGF-EcR-293 without PonA. Chambers were aspirated 24, 48, and 120 h postimplantation. NGF secretion was analyzed in the following ways: (1) NGF protein expression bioactivity was assessed in a PC-12 cell bioassay, and (2) the concentration of secreted NGF was quantified by NGF ELISA. NGF quantification by ELISA reached a maximal release of 12.9 +/- 3.57 ng/mL at 120 h. PC-12 cells exposed to media from induced transfected HEK-293 cell chambers demonstrated higher levels of differentiation compared with controls. We conclude that hNGF-EcR-293 cells can inducibly secrete bioactive NGF when exposed to the induction agent PonA. This regulated delivery system can secrete bioactive NGF for up to 5 days in vivo. We believe this regulated delivery system will be useful for tissue-engineered nerve constructs.     

Quantitative analysis for assessing regional function of liver by using 99mTc-GSA SPECT

In the present study, we developed quantitative index for evaluating regional liver function using 99mTc diethylenetriamine-pentaacetic acid galactosyl human serum albumin (GSA). A three head SPECT equipped with a low energy high resolution parallel hole collimator was used. Used pre-filter was Butterworth and axial images were reconstructed by a ramp filter without attenuation correction. Correlation between SPECT counts and net concentration of activity of radioisotopes was evaluated in basic consideration using LKS and Nine-Ball phantoms. SPECT Counts = 0.6 x RI concentration. There was a simple correlation among GSA receptor amounts (Cr), injected GSA amounts (S), free GSA amounts (Cf), and intra hepatic receptor ratio ((Cr ratio)). Cr = S - Cf. (Cr ratio) = Cr/S, 0 < (Cr ratio) < 1. Injected GSA amounts can be calculated from injected net RI counts. Free GSA amounts can be evaluated from counts of the heart. GSA receptor amounts can be assumed by performing SPECT three times in series. Regional GSA receptor amounts can be evaluated from the ratio between the region's counts and whole counts. In clinical SPECT images, we could evaluate the regional GSA receptor amounts before and after chemolipiodolization. In conclusion, our method is a simple quantitative index of analyzing regional GSA receptor amounts.     

末端标记间日疟寡核苷酸探针在疟疾监测中的应用

本文报道了应用合成间日疟ＤＮＡ片段经同位素末端标记作为探针．检测了２１份经镜检确诊的间日疟病人血样，结果全部阳性．敏感性可测出０．００１３３％的原虫血症，与培养的恶性疟及正常人血没有交叉反应。随后将该探针应用到疟疾监测中，在山东采集的３１０份发热病人血和２４５份流动人口血，应用本探针检测，未出现阳性结果，经镜检复核．结果相符．在安徽省滁州市采集３５２份病灶点人群血，有２８份出现了阳性，阳性率为７．９５％。对以上血样经ＩＦＡ方法进行抗体测定，显示合成间日疟ＤＮＡ探针杂交结果与抗体阳性率具有明显的一致性。结果表明本合成间日疟ＤＮＡ探对可应用于灭疟后期的疟疾监测．特别对流动人口集中检查和传染源检索具有潜在的应用价值。     

The highly sensitive determination of serotonin by using gold nanoparticles (Au NPs) with a localized surface plasmon resonance (LSPR) absorption wavelength in the visible region

The development of improved methods for the synthesis of monodisperse gold nanoparticles (Au NPs) is of high priority because they can be used as substrates for surface-enhanced Raman scattering (SERS) applications relating to biological lipids. Herein, Au NPs have been successfully synthesized via a seed-mediated growth method. The LSPR peak is controlled via adjusting the gold nanoseed component, and different fabrication methods were studied to establish the effect of sonication time on NP size. The simple, facile, and room-temperature method is based on a conventional ultrasonic bath, which leads to ultrasonic energy effects on the size and morphology of the Au NPs. This research offers new opportunities for the production of highly monodispersed spherical Au NPs without the use of a magnetic stirrer method, as evidenced by ultraviolet-visible reflectance spectra and scanning electron microscopy (SEM) analysis. SEM images indicate that the spherical Au NP colloidal particles are stable and reliable, which paves the way for their use as a nanostructured biosensor platform that can be exploited for multiple applications, for example, in materials science, sensing, catalysis, medicine, food safety, biomedicine, etc. The highest enhancement factor that could be achieved in terms of the SERS enhancement activity of these Au NP arrays was determined using 10⁻⁹ M serotonin (5-hydroxytryptamine, 5-HT) as the Raman probe molecules.

The development of improved methods for the synthesis of monodisperse gold nanoparticles (Au NPs) is of high priority because they can be used as substrates for surface-enhanced Raman scattering (SERS) applications relating to biological lipids.     

Hydrogen adsorption mechanism of MOF-74 metal–organic frameworks: an insight from first principles calculations

The microscopic mechanism of the H₂ adsorption of two Mg-MOF-74 isoreticular frameworks, one with a benzenedicarboxylate (BDC) linker and the other with a dihydroxyfumarate (DHF) linker, were studied on the basis of density functional theory (DFT) method. Possible adsorption sites on the internal surface of the two MOFs were detected using ab initio molecular dynamics (AIMD) annealing simulations. The simulations were able to reproduce all adsorption sites which have been experimentally observed for the BDC-based M-MOF-74 frameworks with M = Ni and Zn. In descending order of binding strengths, they are the adsorption sites primarily induced by the open metal sites P₁, the oxygen atoms of the oxido groups P₂ and the aromatic rings P₃. The H₂–framework binding strengths were properly evaluated by taking into account the vibrational zero-point energy (ZPE) contribution. An additional type of adsorption sites induced by the oxygen atoms of the carboxyl groups P₄ is predicted for the Mg-MOF-74 framework. Two types of adsorption sites primarily induced by the open metal sites P₁ and oxygen atoms of the carboxyl groups P₂ were predicted for the DHF-based Mg-MOF-74 framework. Detailed analysis of the electron density showed that the electrostatic interaction of the H₂ molecule with the charge distribution of the local framework environment within a radius of ∼3.5 Å is a key factor to define adsorption positions and binding strength. The absence of the P₄ sites in the BDC-based Zn-MOF-74 framework is caused by the lower charge density at the oxygen atoms induced by less electro-positive metal. The substitution of the nonaromatic DHF linker for the aromatic BDC linker reduces the binding strength at the metal induced adsorption sites by 1.45 kJ mol⁻¹ due to the absence of the aromatic ring.

The microscopic mechanism of the H₂ adsorption of two Mg-MOF-74 isoreticular frameworks, one with a benzenedicarboxylate linker and the other with a dihydroxyfumarate linker, were studied on the basis of density functional theory (DFT) method.     

Background risk of breast cancer and the association between physical activity and mammographic density

Introduction

High physical activity has been shown to decrease the risk of breast cancer, potentially by a mechanism that also reduces mammographic density. We tested the hypothesis that the risk of developing breast cancer in the next 10 years according to the Tyrer-Cuzick prediction model influences the association between physical activity and mammographic density.

Methods

We conducted a population-based cross-sectional study of 38,913 Swedish women aged 40–74 years. Physical activity was assessed using the validated web-questionnaire Active-Q and mammographic density was measured by the fully automated volumetric Volpara method. The 10-year risk of breast cancer was estimated using the Tyrer-Cuzick (TC) prediction model. Linear regression analyses were performed to assess the association between physical activity and volumetric mammographic density and the potential interaction with the TC breast cancer risk.

Results

Overall, high physical activity was associated with lower absolute dense volume. As compared to women with the lowest total activity level (<40 metabolic equivalent hours [MET-h] per day), women with the highest total activity level (≥50 MET-h/day) had an estimated 3.4 cm³ (95% confidence interval, 2.3-4.7) lower absolute dense volume. The inverse association was seen for any type of physical activity among women with <3.0% TC 10-year risk, but only for total and vigorous activities among women with 3.0-4.9% TC risk, and only for vigorous activity among women with ≥5.0% TC risk. The association between total activity and absolute dense volume was modified by the TC breast cancer risk (P_interaction = 0.05). As anticipated, high physical activity was also associated with lower non-dense volume. No consistent association was found between physical activity and percent dense volume.

Conclusions

Our results suggest that physical activity may decrease breast cancer risk through reducing mammographic density, and that the physical activity needed to reduce mammographic density may depend on background risk of breast cancer.     

Proteins in stool as biomarkers for non-invasive detection of colorectal adenomas with high risk of progression

Screening to detect colorectal cancer (CRC) in an early or premalignant state is an effective method to reduce CRC mortality rates. Current stool-based screening tests, e.g. fecal immunochemical test (FIT), have a suboptimal sensitivity for colorectal adenomas and difficulty distinguishing adenomas at high risk of progressing to cancer from those at lower risk. We aimed to identify stool protein biomarker panels that can be used for the early detection of high-risk adenomas and CRC. Proteomics data (LC–MS/MS) were collected on stool samples from adenoma (n = 71) and CRC patients (n = 81) as well as controls (n = 129). Colorectal adenoma tissue samples were characterized by low-coverage whole-genome sequencing to determine their risk of progression based on specific DNA copy number changes. Proteomics data were used for logistic regression modeling to establish protein biomarker panels. In total, 15 of the adenomas (15.8%) were defined as high risk of progressing to cancer. A protein panel, consisting of haptoglobin (Hp), LAMP1, SYNE2, and ANXA6, was identified for the detection of high-risk adenomas (sensitivity of 53% at specificity of 95%). Two panels, one consisting of Hp and LRG1 and one of Hp, LRG1, RBP4, and FN1, were identified for high-risk adenomas and CRCs detection (sensitivity of 66% and 62%, respectively, at specificity of 95%). Validation of Hp as a biomarker for high-risk adenomas and CRCs was performed using an antibody-based assay in FIT samples from a subset of individuals from the discovery series (n = 158) and an independent validation series (n = 795). Hp protein was significantly more abundant in high-risk adenoma FIT samples compared to controls in the discovery (p = 0.036) and the validation series (p = 9e-5). We conclude that Hp, LAMP1, SYNE2, LRG1, RBP4, FN1, and ANXA6 may be of value as stool biomarkers for early detection of high-risk adenomas and CRCs. © 2019 Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.     

Progestogen-only pill associates with false-positive aldosterone/renin ratio screening test

Aldosterone/renin ratio (ARR) is commonly used to screen for primary hyperaldosteronism (Conn’s disease). A number of drugs can alter ARR measurements, thus requiring omission before testing. However, hormonal agents such as the combined oral contraceptive (COCP) or progestogen-only pill (POP) are not listed for omission. A 20-year-old woman was referred to the endocrinology team, following investigations for syncope by her cardiologist, when ARR was found to be elevated. She was taking POP (Cerelle^®) while having ARR measured. After omitting POP for four weeks, plasma aldosterone concentration was reduced by 52% (from 560 pmol/L to 271 pmol/L, reference range: 100–450 pmol/L), plasma renin concentration increased by 253% (from 3.6 mU/L to 12.7 mU/L, reference range: 5.4–30 mU/L) and ARR reduced from 156 to 21 (–86.5%) (reference range: <80 suggests Conn’s unlikely). To the best of our knowledge, this is the first reported case of POP-related false-positive ARR screening for primary hyperaldosteronism. Omission of POP should, therefore, be considered in women undergoing ARR measurement.Key words: Conn’s disease, hypertension, oral contraceptive pill     

Prognostic biomarkers in men with metastatic castration-resistant prostate cancer receiving [177Lu]-PSMA-617

European Journal of Nuclear Medicine and Molecular Imaging - We analysed quantitative biomarkers derived from both baseline whole-body imaging and blood serum to identify prognostic markers in...