Ex vivo high resolution magic angle spinning metabolic profiles describe intratumoral histopathological tissue properties in adult human gliomas

In gliomas one can observe distinct histopathological tissue properties, such as viable tumor cells, necrotic tissue or regions where the tumor infiltrates normal brain. A first screening between the different intratumoral histopathological tissue properties would greatly assist in correctly diagnosing and prognosing gliomas. The potential of ex vivo high resolution magic angle spinning spectroscopy in characterizing these properties is analyzed and the biochemical differences between necrosis, high cellularity and border tumor regions in adult human gliomas are investigated. Statistical studies applied on sets of metabolite concentrations and metabolite ratios extracted from 52 high resolution magic angle spinning recordings coming from patients with different grades of glial tumors show a strong correlation between the histopathological tissue properties and the considered metabolic profiles, regardless of the malignancy grade. The results are in agreement with the pathology obtained by the histopathological examination that succeeded the high resolution magic angle spinning measurements. The metabolite concentration set can better differentiate between the considered histopathological tissue properties compared to the ratios. Representative reference tissue models describing the metabolic behavior are extracted for characterizing the intratumoral tissue properties. The proposed metabolic profiles reflect that the metabolites behavior is interconnected, and typical biochemical patterns emerge for each histopathological tissue property. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc.     

Expression of eNOS in the lungs of neonates with pulmonary hypertension

Background

Neonatal hypoxemic respiratory failure (NHRF) is usually associated with reversible persistent pulmonary hypertension (PPHN). Congenital diaphragmatic hernia (CDH), a cause of refractory NHRF, is associated with irreversible pulmonary hypertension. Nitric oxide (NO) generated in the pulmonary vascular endothelium by endothelial nitric oxide synthase (eNOS) plays a pivotal role in perinatal circulatory adaptation.

Objective

To compare the expression of eNOS using IHC in postmortem lung tissue from newborns diagnosed clinically with PPHN and CDH.

Design/methods

Formalin-fixed lung tissue from infants who died following treatment for PPHN (n = 12) or CDH (n = 8) and age and gender matched controls who died from non-respiratory causes (Control, n = 14) was evaluated for expression and staining intensity (1–4 scale) of eNOS using IHC.

Results

Mean gestational and postnatal age was comparable across groups. Histological evidence of chronic lung disease, pulmonary hypoplasia and pulmonary hypertension were seen more frequently in CDH compared to PPHN and control infants. eNOS expression was increased in arteriolar media of PPHN infants compared to Controls (p = 0.027). CDH infants had increased intensity of staining for eNOS in the arteriolar endothelium (p = 0.022) compared to control and PPHN infants and in the alveolar lining (p = 0.002) compared to Controls.

Conclusions

Upregulation of eNOS was seen both in infants with CDH and PPHN but was more marked in infants with CDH. These findings may have implications for understanding disease pathophysiology in cases with fatal outcome and development of novel therapies for neonatal pulmonary hypertension.     

A toxicogenomic approach for identifying biomarkers for myelosuppressive anemia in rats

Myelosuppressive anemia is a serious side effect associated with several drugs. Thus, there is an increasing demand for sensitive biomarkers for the early detection of myelosuppressive anemia during toxicological studies. We applied a toxicogenomic approach to identify useful biomarker genes reflecting myelosuppressive anemia in the rat liver. Expression of the hemoglobin beta chain complex (Hbb), aminolevulinic acid synthase 2 (Alas2), and cell division cycle 25 homolog B (Cdc25b) genes changed as a result of anemia induced by the myelosuppressive agents linezolid, cisplatin, and carboplatin, suggesting that these genes may be suitable biomarkers. Moreover, evaluation of perfused and unperfused livers indicated that changes in the expression of these genes originate in circulating reticulocytes in the liver. Erythroid differentiation-associated changes in expression of the Hbb, Alas2, and Cdc25b genes were confirmed in vitro using Friend leukemia cells. In conclusion, our current research provides novel evidence that gene expression in circulating reticulocytes contained in the liver changes dramatically under myelosuppressive conditions. While further large-scale validation studies are needed, our results indicate that the genes we identified might be useful biomarkers for the sensitive detection of myelosuppressive anemia in rats.     

A fast and accurate method for the determination of total and soluble fluorine in toothpaste using high-resolution graphite furnace molecular absorption spectrometry and its comparison with established techniques

A fast and reliable method has been developed for the determination of total and soluble fluorine in toothpaste, important quality control parameters in dentifrices. The method is based on the molecular absorption of gallium mono-fluoride, GaF, using a commercially available high-resolution continuum source atomic absorption spectrometer. Transversely heated platform tubes with zirconium as permanent chemical modifier were used throughout. Before each sample injection, a palladium and zirconium modifier solution and a gallium reagent were deposited onto the graphite platform and thermally pretreated to transform them into their active forms. The samples were only diluted and introduced directly into the graphite tube together with additional gallium reagent. Under these conditions the fluoride was stable up to a pyrolysis temperature of 550 °C, and the optimum vaporization (molecule formation) temperature was 1550 °C. The GaF molecular absorption was measured at 211.248 nm, and the limits of detection and quantification were 5.2 pg and 17 pg, respectively, corresponding to a limit of quantification of about 30 μg g(-1) (ppm) F in the original toothpaste. The proposed method was used for the determination of total and soluble fluorine content in toothpaste samples from different manufactures. The samples contained different ionic fluoride species and sodium monofluorophosphate (MFP) with covalently bonded fluorine. The results for total fluorine were compared with those obtained with a modified conventional headspace gas chromatographic procedure. Accuracy and precision of the two procedures were comparable, but the proposed procedure was much less labor-intensive, and about five times faster than the latter one.     

Elemental and structural analysis of silicon forms in herbal drugs using silicon-29 MAS NMR and WD-XRF spectroscopic methods

The objective of this work was to study concentration of silicon and its structural forms present in herbal drugs. Equisetum arvense and Urtica dioica L. from teapot bags, dietary supplements (tablets and capsules) containing those herbs, dry extract obtained from a teapot bag of E. arvense, and samples of the latter herb harvested in wild habitat over four months were studied using wavelength dispersive X-ray spectroscopy (WD-XRF) and high-resolution solid-state ²⁹Si NMR. The highest concentration of Si, ca. 27 mg/g, was found in the herbal material from the teapot bags containing E. arvense. The Si content in natural E. arvense (whole plants) increased from May to August by ca. 7 mg/g, reaching value 26 mg/g. Three different silicon forms were detected in the studied herbal samples: Si(OSi)4 (Q₄), Si(OH)(OSi)3 (Q₃) and Si(OH)2(OSi)2 (Q₂). Those sites were populated in E. arvense in the following order: Q₄ ? Q₃ > Q₂. A dramatic, ca. 50-fold decrease of the Si concentration during the infusion process was observed. The infusion process and the subsequent drying procedure augmented population of the Q₄ sites at the cost of the Q₂ sites. The WD-XRF and ²⁹Si NMR methods occurred useful and complementary in the study of herbal materials.     

Surfactant replacement therapy

Surfactant replacement therapy (SRT) has a proven role in the treatment of neonatal respiratory distress syndrome and severe meconium aspiration syndrome in infants, and may have a role in the treatment of pediatric patients with ARDS. Although newer delivery mechanisms and strategies are being studied, the classic surfactant administration paradigm consists of endotracheal intubation, surfactant instillation into the lung, and stabilization with mechanical ventilation followed by extubation when stable on low respiratory support. Currently, this surfactant administration procedure is bundled into Current Procedural Terminology (CPT) codes used when providing intensive care. A specific CPT code for surfactant administration is scheduled to be introduced in 2007. This article reviews clinical issues in SRT and the practice management considerations necessary to provide this care.     

MA-NOS radical sigmoidectomy: report of a transvaginal resection in the human

Background  With available laparoscopic and endoscopic instruments/technology a standard radical sigmoid resection is feasible and safe using transvaginal minilaparoscopic-assisted natural orifice surgery (MA-NOS). Methods  The intervention was a transvaginal MA-NOS sigmoidectomy in a 78-year-old woman with a sigmoid adenocarcinoma. Maintaining triangulation the surgeon positioned himself at the right side of the patient and used the transvaginal trocar for dissection and stapling of both the inferior mesenteric vessels and the upper rectum. The colonic resection was performed extracorporeally in the conventional fashion and was followed by an intra-abdominal endoscopically assisted stapled anastomosis. Results  Advantages of minimally invasive surgery seemed to be enhanced with this hybrid laparoscopic approach. Postoperative course was uneventful. All oncological principles governing resection and management were accomplished and the pathology examination confirmed a T3N1 lesion. The patient was discharged on the fourth postoperative day. Conclusion  Transvaginal MA-NOS radical sigmoidectomy is a feasible and oncologically safe procedure. MA-NOS is a realistic option for avoiding the need of assisting incisions and related morbidity in the laparoscopic resection of large intra-abdominal lesions. Combined hybrid laparoscopic NOS in humans (MA-NOS) currently provides a safe and reliable way of defining future clinical applications and advantages of NOS and NOTES. Additionally, it stimulates the active development and evaluation of the underpinning technologies and instrumentation.     

Intraluminal magnetisation of bowel by ferromagnetic particles for retraction and manipulation by magnetic probes

Feasibility studies are needed to demonstrate that safe and effective manipulation of bowel during Minimal Access Surgery (MAS) can be obtained by use of magnetic force. This paper characterises two classes of magnetic particles: stainless steel microparticles (SS-μPs) and iron oxide nanoparticles (IO-nPs) in terms of their magnetisation, chemical composition, crystallinity, morphology and size distribution. Both magnetic particles were dispersed in a high viscosity biological liquid for intraluminal injection of bowel. Ex vivo porcine bowel segments were then retracted by permanent magnetic probes of 5.0 and 10 mm diameter. Strong retraction forces reaching 6 N maximum were obtained by magnetic fluid based on dispersion of SS-μPs. In contrast, the IO-nP-based magnetic liquid generated less attraction force, due to both lower magnetic and solution properties of the IO-nPs. The comparison of the two particles allowed the identification of the rules to engineer the next generation of particles. The results with SS-μPs provide proof on concept that intraluminal injection of magnetic fluid can generate sufficient force for efficient bowel retraction. Thereafter we shall carry out in vivo animal studies for efficacy and safety of both types of ferrofluids.     

Assessment of early docetaxel response in an experimental model of human breast cancer using DCE‐MRI,ex vivo HR MAS,and in vivo 1H MRS

The purpose of this study was to evaluate the use of dynamic contrast‐enhanced (DCE) MRI, in vivo ¹H MRS and ex vivo high resolution magic angle spinning (HR MAS) MRS of tissue samples as methods to detect early treatment effects of docetaxel in a breast cancer xenograft model (MCF‐7) in mice. MCF‐7 cells were implanted subcutaneously in athymic mice and treated with docetaxel (20, 30, and 40 mg/kg) or saline six weeks later. DCE‐MRI and in vivo ¹H MRS were performed on a 7 T MR system three days after treatment. The dynamic images were used as input for a two‐compartment model, yielding the vascular parameters K^trans and v_e. HR MAS MRS, histology, and immunohistochemical staining for proliferation (Ki‐67), apoptosis (M30 cytodeath), and vascular/endothelial cells (CD31) were performed on excised tumor tissue. Both in vivo spectra and HR MAS spectra were used as input for multivariate analysis (principal component analysis (PCA) and partial least squares regression analysis (PLS)) to compare controls to treated tumors. Tumor growth was suppressed in docetaxel‐treated mice compared to the controls. The anti‐tumor effect led to an increase in K^trans and v_e values in all the treated groups. Furthermore, in vivo MRS and HR MAS MRS revealed a significant decrease in choline metabolite levels for the treated groups, in accordance with reduced proliferative index as seen on Ki‐67 stained sections. In this study DCE‐MRI, in vivo MRS and ex vivo HR MAS MRS have been used to demonstrate that docetaxel treatment of a human breast cancer xenograft model results in changes in the vascular dynamics and metabolic profile of the tumors. This indicates that these MR methods could be used to monitor intra‐tumoral treatment effects. Copyright © 2009 John Wiley & Sons, Ltd.