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Many metabolic phenotypes in cancer cells are also characteristic of proliferating non-transformed mammalian cells, and attempts to distinguish between phenotypes resulting from oncogenic perturbation from those associated with increased proliferation are limited. Here, we examined the extent to which metabolic changes corresponding to oncogenic KRAS expression differed from those corresponding to epidermal growth factor (EGF)-driven proliferation in human mammary epithelial cells (HMECs). Removal of EGF from culture medium reduced growth rates and glucose/glutamine consumption in control HMECs despite limited changes in respiration and fatty acid synthesis, while the relative contribution of branched-chain amino acids to the TCA cycle and lipogenesis increased in the near-quiescent conditions. Most metabolic phenotypes measured in HMECs expressing mutant KRAS were similar to those observed in EGF-stimulated control HMECs that were growing at comparable rates. However, glucose and glutamine consumption as well as lactate and glutamate production were lower in KRAS-expressing cells cultured in media without added EGF, and these changes correlated with reduced sensitivity to GLUT1 inhibitor and phenformin treatment. Our results demonstrate the strong dependence of metabolic behavior on growth rate, and provide a model to distinguish the metabolic influences of oncogenic mutations and non-oncogenic growth.

Background: The Functional Movement Screen (FMS) is used to evaluate key movement patterns, functional symmetry, and identify individuals that are at elevated risk of injury. The purpose of this study was to assess whether dynamic postural control is a significant component of the composite FMS score by comparing it with Y-Balance Test (YBT) reach distances. Methods: Seventy-eight participants (including 40 males) performed the standardized FMS protocol followed by the YBT. The YBT reach distances were normalized to leg length and averaged between sides and trials. The individual reach directions were evaluated, and were also summed to form an aggregate YBT distance (TotalY). Results: We observed weak correlations between the composite FMS score and normalized posterolateral reach, normalized posteromedial reach, and the TotalY (r=0.36, 0.37, and 0.36, respectively; all p< 0.05). There was no correlation between the composite FMS score and normalized anterior reach (r=0.22; p=0.053). Together these findings demonstrate partial correspondence between the two tests. Conclusion: This indicates that dynamic postural control is a small component of the aggregate FMS score.

We investigated the compartmentation of the catabolism of dodecanedioate (DODA), azelate, and glutarate in perfused rat livers, using a combination of metabolomics and mass isotopomer analyses. Livers were perfused with recirculating or nonrecirculating buffer containing one fully 13C-labeled dicarboxylate. Information on the peroxisomal versus mitochondrial catabolism was gathered from the labeling patterns of acetyl-CoA proxies, i.e. total acetyl-CoA, the acetyl moiety of citrate, C-1 + 2 of β-hydroxybutyrate, malonyl-CoA, and acetylcarnitine. Additional information was obtained from the labeling patterns of citric acid cycle intermediates and related compounds. The data characterize the partial oxidation of DODA and azelate in peroxisomes, with terminal oxidation in mitochondria. We did not find evidence of peroxisomal oxidation of glutarate. Unexpectedly, DODA contributes a substantial fraction to anaplerosis of the citric acid cycle. This opens the possibility to use water-soluble DODA in nutritional or pharmacological anaplerotic therapy when other anaplerotic substrates are impractical or contraindicated, e.g. in propionic acidemia and methylmalonic acidemia.

Concerns about healthcare-associated infections and the global crisis in antimicrobial resistance has combined to accentuate the fears around so-called "superbugs". In Ireland there is no single agreed indicator regarded as a true measure of the level of methicillin resistant Staphylococcus aureus (MRSA) in hospitals. The objective of this study was to compare two crude measures of MRSA - the percentage of bacteraemia caused by MRSA and the incidence rate (per 1000 bed days used) of MRSA bacteraemia in six acute hospitals. We examined all blood cultures positive for S. aureus (methicillin sensitive and resistant) from 2002 to 2004 in the Health Service Executive (HSE) Mid-Western Area of Ireland. Hospital In-Patient Enquiry (HIPE) data was used to determine monthly in-patient bed days used. Of 245 patient episodes of bacteraemia, 119 were MRSA. The trends in the percentage of isolates that were MRSA and the incidence rate calculated were compared. The incidence rate appears to be a more reliable and robust indicator of MRSA in hospitals than the percentage. Despite many difficulties in interpreting indicators of MRSA they should not preclude the regular publication of data at least at regional level in Ireland.

The effects of water-filtered infrared-A (wIRA) and of convective heat on viability, inflammation, inducible free radicals and antioxidative power were investigated in natural and viable skin using the ex vivo Bovine Udder System (BUS) model. Therefore, skin samples from differently treated parts of the udder of a healthy cow were analyzed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test, by prostaglandin E2 (PGE2) measurement and by electron spin resonance (ESR) spectroscopy. Neither cell viability, the inflammation status, the radical status or the antioxidative defence systems of the skin were significantly affected by wIRA applied within 30 min by using an irradiance of 1900 W m(-2) which is of relevance for clinical use, but which exceeded the maximum solar IR-A irradiance at the Earth's surface more than 5 times and which resulted in a skin surface temperature of about 45 °C without cooling and of about 37 °C with convective cooling by air ventilation. No significant effects on viability and on inflammation were detected when convective heat was applied alone under equivalent conditions in terms of the resulting skin surface temperatures and exposure time. As compared with untreated skin, free radical formation was almost doubled, whereas the antioxidative power was reduced to about 50% after convective heating to about 45 °C.

article i nfo Tetrapyrroles are multisided natural products which are of relevance in clinical medicine. Owing to their specific accumulation in tumour tissue, porphyrins, metalloporphyrins and chlorins have been used as in photodynamic therapy and optical imaging. Moreover, their specific uptake into inflammatory atheromatous plaques via LDL endocytosis has been reported. The present study is concerned with the synthesis of 68 Ga labelled porphyrin derivatives and an in vitro assessment of the utility of radiotracers in positron emission tomography. A set of five porphyrin derivatives were labelled using 68 Ga from a commercially obtained radionuclide generator. Dedicated post-processing of the generator eluate was conducted to allow for labelling in aqueous media and also under anhydrous conditions. Challenge studies and incubation in human serum confirmed the stability of the tracers. Plasma protein binding was investigated in order to confirm the presence of freely diffusible radioligand in plasma. A preliminary microPET study in a tumour-bearing rat resulted in a clear visualisation of the tumour.

A review of patient notification exercises (PNEs) carried out in Ireland between 1997 and 2011 to investigate potential exposure to blood-borne viruses (BBVs) in healthcare settings was undertaken to inform future policy and practice. A questionnaire was sent to key informants in the health services to identify all relevant PNEs. Structured interviews were conducted with key investigators, and available documentation was examined. Ten BBV-related PNEs were identified. Despite testing over 2000 patients, only one case of transmission was found. However, in-depth local investigations before undertaking the PNEs identified six cases of healthcare-associated transmission.

Tumour blood flow before and during clinically relevant mild hyperthermia exhibits pronounced heterogeneity. Flow changes upon heating are not predictable and are both spatially and temporally highly variable. Flow increases may result in improved heat dissipation to the extent that therapeutically relevant tissue temperatures may not be achieved. This holds especially true for tumours or tumour regions in which flow rates are substantially higher than in the surrounding normal tissues. Changes in tumour oxygenation tend to reflect alterations in blood flow upon hyperthermia. An initial improvement in the oxygenation status, followed by a return to baseline levels (or even a drop to below baseline at high thermal doses) has been reported for some tumours, whereas a predictable and universal occurrence of sustained increases in O(2) tensions upon mild hyperthermia is questionable and still needs to be verified in the clinical setting. Clarification of the pathogenetic mechanisms behind possible sustained increases is mandatory. High-dose hyperthermia leads to a decrease in the extracellular and intracellular pH and a deterioration of the energy status, both of which are known to be parameters capable of acting as direct sensitisers and thus pivotal factors in hyperthermia treatment. The role of the tumour microcirculatory function, hypoxia, acidosis and energy status is complex and is further complicated by a pronounced heterogeneity. These latter aspects require additional critical evaluation in clinically relevant tumour models in order for their impact on the response to heat to be clarified.

In this second of two companion articles, we compare the mass isotopomer distribution of metabolites of liver gluconeogenesis and citric acid cycle labeled from NaH(13)CO(3) or dimethyl [1,4-(13)C(2)]succinate. The mass isotopomer distribution of intermediates reveals the reversibility of the isocitrate dehydrogenase + aconitase reactions, even in the absence of a source of alpha-ketoglutarate. In addition, in many cases, a number of labeling incompatibilities were found as follows: (i) glucose versus triose phosphates and phosphoenolpyruvate; (ii) differences in the labeling ratios C-4/C-3 of glucose versus (glyceraldehyde 3-phosphate)/(dihydroxyacetone phosphate); and (iii) labeling of citric acid cycle intermediates in tissue versus effluent perfusate. Overall, our data show that gluconeogenic and citric acid cycle intermediates cannot be considered as sets of homogeneously labeled pools. This probably results from the zonation of hepatic metabolism and, in some cases, from differences in the labeling pattern of mitochondrial versus extramitochondrial metabolites. Our data have implications for the use of labeling patterns for the calculation of metabolic rates or fractional syntheses in liver, as well as for modeling liver intermediary metabolism.

Purpose The neurohormones melatonin and dopamine mediate clock-dependent/circadian regulation of inner retinal neurons and photoreceptor cells and in this way promote their functional adaptation to time of day and their survival. To fulfill this function they act on melatonin receptor type 1 (MT1 receptors) and dopamine D4 receptors (D4 receptors), respectively. The aim of the present study was to screen transcriptional regulators important for retinal physiology and/or pathology (Dbp, Egr-1, Fos, Nr1d1, Nr2e3, Nr4a1, Pgc-1α, Rorβ) for circadian regulation and dependence on melatonin signaling/MT1 receptors or dopamine signaling/D4 receptors. Methods This was done by gene profiling using quantitative polymerase chain reaction in mice deficient in MT1 or D4 receptors. Results The data obtained determined Pgc-1α and Nr4a1 as transcriptional targets of circadian melatonin and dopamine signaling, respectively. Conclusions The results suggest that Pgc-1α and Nr4a1 represent candidate genes for linking circadian neurohormone release with functional adaptation and healthiness of retina and photoreceptor cells.

The nucleoredoxin-like gene Nxnl1 (Txnl6) and its paralogue Nxnl2 encode the rod-derived cone viability factors (RdCVF and RdCVF2), which increase the resistance to photooxidative damage and have therapeutic potential for the survival of cones in retinitis pigmentosa. In this study, the transcription of Nxnl genes was investigated as a function of the day/night cycle in rats. The transcript levels of Nxnl1 and Nxnl2 were seen to display daily rhythms with steadily increasing values during the light phase and peak expression around dark onset in preparations of whole retina, photoreceptor cells and—but only in regard to Nxnl1—in photoreceptor-related pinealocytes. The cycling of Nxnl1 but not that of Nxnl2 persisted in constant darkness in the retina. This suggests that daily regulation of Nxnl1 is driven by a circadian clock, whereas that of Nxnl2 is promoted by environmental light. The present data indicate clock- and light-dependent regulations of nucleoredoxin-like genes that may be part of a protective shield against photooxidative damage.

Background: The butterfly save technique is commonly used by ice hockey goaltenders and has recently been identified as a potential mechanism for hip joint injuries due to the extreme body positions involved. Unfortunately, commonly used kinematic marker sets that determine these body positions are heavily influenced by skin motion artifact and are obscured by protective equipment, making it difficult to obtain reliable measures of hip motion. Purpose: To create a new kinematic protocol that could be used when protective equipment prevents typical marker placements and to use this protocol to quantify hip kinematics and butterfly performance in 4 different goalie pad conditions. Study Design: Controlled laboratory study. Methods: A new marker set consisting of marker clusters attached to the lateral thigh and posterior leg was developed. This marker set was verified by evaluating the root mean square (RMS) difference between the developed testing marker set and the calibrated anatomic systems technique marker set during passive range of motion (ROM) tests. The testing marker set was then used in a repeated-measures study in which 12 junior goaltenders performed 5 butterfly movements on synthetic ice, in 4 different goalie pad conditions (control, flexible-wide leg channel, flexible-tight leg channel, and stiff-wide leg channel). Results: The grouped RMS differences and SDs calculated during verification were 1.43° ± 0.41°, 1.0° ± 0.39°, and 3.32° ± 1.32° for hip flexion-extension, abduction-adduction, and internal-external rotation, respectively. There was no significant main effect of goal pad condition on the peak amount of hip internal rotation; however, there was a significant main effect of goal pad condition on the butterfly width ( P = .022). Post hoc comparisons revealed that the butterfly width was significantly smaller in the control pad condition compared with the flexible-tight pad condition ( P = .03). Conclusion: The new marker set enabled measurements of hip joint kinematics while subjects are wearing protective equipment that are not possible with other marker sets. Interindividual variations in performance of the butterfly technique influenced the amount of hip internal rotation achieved; however, on average, goaltenders exceeded their active internal ROM during butterfly movements. Clinical Relevance: Exceeding internal rotation range of hip motion may make goaltenders susceptible to hip injuries such as femoral acetabular impingement.

Background Protein-energy malnutrition is common among infants with congenital heart disease. We hypothesized that infants with hypoplastic left heart syndrome (HLHS) are at risk for malnutrition. Objective To determine the prevalence of and risk factors for malnutrition in infants undergoing palliative surgery for HLHS. Methods Retrospective chart review of 50 infants with HLHS who underwent both stage 1 Norwood and bidirectional Glenn (BDG) procedures over 4.5 y. Results After a median hospital stay of 21 d, median discharge weight was 3.4 kg, unchanged from admission. Adjusting for weight on admission, children with longer length of hospital stay, longer intensive care unit stay, shorter duration of parental nutrition therapy, and higher diuretic dosage at discharge had a lower weight-for-age Z score at discharge ( R 2 = 0.85). On admission for BDG, median weight-for-age Z score was −2.0. After adjusting for weight on discharge from the initial hospitalization, children with fewer calories/ounce of their enteral nutrition at discharge, worse right ventricular function, more frequent readmissions, and higher oxygen saturation at discharge had a lower weight-for-age Z score at BDG ( R 2 = 0.49). Conclusions Malnutrition is common in infants with HLHS after stage 1 palliation. Variables associated with more complex postoperative course and imbalance between systemic and pulmonary blood flow were all associated with poorer nutritional status. When adjusting for these factors, the use of parenteral nutrition and high calorie enteral feeds were associated with improved nutritional status. Aggressive parenteral and enteral nutritional therapy might help reduce the prevalence of growth faltering in infants who have HLHS.

The expression and activity of P-glycoprotein (pGP) play a role in the multidrug resistance of tumors. Because solid-growing tumors often show pronounced hypoxia or extracellular acidosis, this study attempted to analyze the impact of an acidic environment on the expression and activity of pGP and on the cytotoxicity of chemotherapeutic agents. For this, prostate carcinoma cells were exposed to an acidic extracellular environment (pH 6.6) for up to 24 hours. pGP activity was more than doubled after 3 to 6 hours of incubation in acidic medium, whereas cellular pGP expression remained constant, indicating that increased transport rate is the result of functional modulation. In parallel, the cytotoxic efficacy of daunorubicin showed pronounced reduction at low pH, an effect that was reversible on coincubation with a pGP inhibitor. A reduction of intracellular Ca2+ concentration by 35% under acidic conditions induced a higher transport rate of pGP, an effect comparable to that found on inhibition of protein kinase C (PKC). These data indicate that pGP activity is increased by acidic pH presumably as a result of lowered intracellular calcium levels and inhibition of PKC. These findings may explain the reduced cytotoxicity of chemotherapeutic agents in hypoxic/acidic tumors.

This study investigated long-term microenvironmental responses (oxygenation, perfusion, metabolic status, proliferation, vascular endothelial growth factor (VEGF) expression and vascularisation) to chronic hypoxia in experimental tumours. Experiments were performed using s.c.-implanted DS-sarcomas in rats. In order to induce more pronounced tumour hypoxia, one group of animals was housed in a hypoxic atmosphere (8% O(2)) for the whole period of tumour growth (chronic hypoxia). A second group was acutely exposed to inspiratory hypoxia for only 20 min prior to the measurements (acute hypoxia), whereas animals housed under normal atmospheric conditions served as controls. Acute hypoxia reduced the median oxygen partial pressure (pO(2)) dramatically (1 vs 10 mmHg in controls), whereas in chronically hypoxic tumours the pO(2) was significantly improved (median pO(2)=4 mmHg), however not reaching the control level. These findings reflect the changes in tumour perfusion where acutely hypoxic tumours show a dramatic reduction of perfused tumour vessels (maybe the result of a simultaneous reduction in arterial blood pressure). In animals under chronic inspiratory hypoxia, the number of perfused vessels increased (compared to acute hypoxia), although the perfusion pattern found in control tumours was not reached. In the chronically hypoxic animals, tumour cell proliferation and tumour growth were significantly reduced, whereas no differences in VEGF expression and vascular density between these groups were observed. These results suggest that long-term adaptation of tumours to chronic hypoxia in vivo, while not affecting vascularity, does influence the functional status of the microvessels in favour of a more homogeneous perfusion.

Objective . To evaluate the impact of treatment for genital cancer on quality of life and body image to determine patients' therapy-related needs for quality improvement of medical care before and after surgery. Methods . We started to evaluate women with cervical cancer planned for pelvic exenteration in 1993 and integrated women planned for a Wertheim–Meigs surgery in 1995 before surgery, 4 and 12 months after surgery. Thanks to funding since 1999, more than 400 patients with a diagnosis of genital ( n = 185) or breast ( n = 217) cancer participated in this prospective study until July 2003. In this paper, we will focus on n = 129 women with cervical cancer. The assessment protocol included objective questionnaires for quality of life and body image (CARES; EORTC; Body image by Strauss and Appelt). The evaluation of quality of life incorporated five dimensions: physical and psychosocial health, marital and sexual status, and medical interaction. Results . Before surgery, women with a Wertheim's procedure indicated significantly less problems concerning the quality of life global score ( P = 0.002) and several subscales compared to women with a pelvic exenteration. After surgery, both groups indicated their sexual problems to be the greatest restriction in terms of quality of life, especially in women with non-reconstructive surgery as well as in women with adjuvant radio and/or chemotherapy. Concerning body image, attractiveness or self-confidence was significantly reduced postoperatively compared to the preoperative status for both groups ( P = 0.000), and also worsened with the extent of treatment. Worries about the patient's family persisted over time and represented the most important item about all questions concerning quality of life as well as the fear of recurrence. Conclusion . This on-going study demonstrates the interferences between the treatment modality and the patient's quality of life, especially about sexuality and body image. Our results suggest not only to provide reconstructive surgery if possible, but also to integrate psychosocial information aspects on future quality of life outcome before surgery as well as to offer psychosocial support related to the extent of treatment modality after surgery.

The effects of combined and simultaneously applied localised 43 degrees C hyperthermia (HT) and an antivascular bacteriochlorophyll-serine-based photodynamic therapy (Bchl-ser-PDT) on tumour growth and several microenvironmental parameters were examined. Rats bearing DS-sarcomas were allocated to treatment groups: (i) sham-treatment (control), (ii) Bchl-ser-PDT (20 mg kg(-1) i.v.), (iii) localised HT, (iv) Bchl-ser-PDT+HT. The light source used was an infrared-A irradiator, which, by use of appropriate filters, delivered the different ranges of wavelengths required. Following treatment, tumour volume was monitored. The greatest tumour growth inhibition was seen with Bchl-ser-PDT+HT, and subsequent experiments identified the pathophysiological basis for this effect. Red blood cell flux in tumour microvessels declined rapidly upon Bchl-ser-PDT+HT, reaching approximately 10% of initial values by the end of treatment. Similarly, tumour oxygenation worsened, reaching almost anoxic levels by the end of the treatment period. Assessment of metabolic parameters showed a pronounced increase in lactate levels and a decrease in ATP concentrations after combined treatment. The results presented suggest that vascular collapse and flow stasis resulting in a deterioration of tumour oxygenation and a switch from oxidative to glycolytic glucose turnover are key elements in the tumour eradication seen with this novel approach in which an antivascular PDT and HT are combined and simultaneously applied.

This study was undertaken to explore the metabolic fate of acetyl-L-carnitine in rat brain. To measure the flux of carbon atoms into anabolic processes occurring at regional levels, we have injected [1-(14)C]acetyl-L-carnitine into the lateral brain ventricle of conscious rats. After injection of [1-(14)C]acetyl-L-carnitine, the majority of radioactivity was recovered as 14CO2 expired (60% of that injected). The percentage of radioactivity recovered in brain was 1.95, 1.60, 1.30, and 0.93% at 1, 3, 6, and 22 h, respectively. Radioactivity distribution in various lipid components indicated that the fatty acid moiety of phospholipid contained the majority of radioactivity. The radioactive profile of these fatty acids showed that the acetyl moiety of acetyl-L-carnitine was incorporated into saturated (60%), monounsaturated (15%), and polyunsaturated (25%) fatty acids [mainly present in 20:4 (5.2%) and 22:6 (7.8%)]. Injection in the brain ventricle of radioactive glucose, the major source of acetyl-CoA in the CNS, revealed that glucose was a precursor of saturated (85%) and monounsaturated (15%) but not of polyunsaturated fatty acids. Thus, this study demonstrated distinct fates of glucose and acetyl-L-carnitine following intracerebroventricular injection. In summary, these data implicate acetyl-L-carnitine as an important member of a complex acetate trafficking system in brain lipid metabolism.

Phospholipids and sterols are known to have multiple functions in reproductive tissue of mammals. High concentrations of the cholesterol precursor desmosterol have been described in testis, epididymis, and spermatozoa of various species. These findings and the recent discovery of some cholesterol precursors as meiosis-activating sterols suggest important functions of cholesterol precursors in fertility. Many sterol intermediates appear from the 19-step conversion of lanosterol, the first sterol synthesized in the cascade of cholesterol synthesis, to cholesterol. The bio- chemical basis of the genetically inherited Smith-Lemli- Opitz syndrome has been described as a defective conver- sion of 7-dehydrocholesterol to cholesterol. Since this dis- covery, interest has focused on this special cholesterol pre- cursor. Here, we report high concentrations of 7- and 8-dehydrocholesterol in caput epididymidis and spermato- zoa derived from caput epididymidis of Sprague-Dawley and Wistar rats, which comprised up to 30% of total sterols. In contrast to caput epididymidis, 7- and 8-dehydrocholes- terol were barely detected in cauda epididymidis or testis. Desmosterol increased several times from caput to cauda epididymidis. This is the first report of the natural ap- pearance of high concentrations of dehydrocholesterols in mammalian tissue, and it underlines the putative impor- tance of cholesterol precursors in reproductive tissue. — Lindenthal, B., T. A. Aldaghlas, J. K. Kelleher, S. M. Henkel, R. Tolba, G. Haidl, and K. von Bergmann. Neutral sterols of rat epididymis: high concentrations of dehydrocholesterols in rat caput epididymidis. J. Lipid Res. 2001. 42: 1089-1095.

Perfusion and oxygenation of experimental tumours were studied during angiotensin II (AT II) administration whereby the rate of the continuous AT II infusion was chosen to increase the mean arterial blood pressure (MABP) by 50–70 mmHg. In subcutaneous DS- sarcomas the red blood cell (RBC) flux was assessed using the laser Doppler technique and the mean tumour oxygen partial pressure (p O 2) was measured polarographically using O 2-sensitive catheter and needle electrodes. Changes in RBC flux with increasing MABP depended mainly on tumour size. In small tumours, RBC flux decreased with rising MABP whereas in larger tumours RBC flux increased parallel to the MABP. As a result of these volume-dependent effects on tumour blood flow, the impact of AT II on tumour p O 2 was also mainly tumour volume-related. In small tumours oxygenation decreased with increasing MABP during AT II infusion, whereas in large tumours a positive relationship between blood pressure and O 2 status was found. This disparate behaviour might be the result of the co-existence of two functionally distinct populations of tumour vessels. In small tumours, perfusion decreases presumably due to vasoconstriction of pre-existing host vessels feeding the tumour. In larger malignancies, newly formed tumour vessels predominate and seem not to have this vasoresponsive capability (lack of smooth muscle cells and/or AT receptors), resulting in an improvement of perfusion which is not tumour-related per se, but is due to the increased perfusion pressure. © 2000 Cancer Research Campaign

Heart failure is predominantlya disease ofolderpeople,affecting almost 1 in 10 of those over the age of 80 [1]and accounting for 5% of hospital admissions in this agegroup [2]. Although an overall 5-year survival figure of50% has been quoted [3], prognosis is considerablyworse in older patients, with a corresponding figure ofless than 20% in those aged 80 or over [4].Angiotensin-converting enzyme inhibitors [5] andb-blockers [6, 7] reduce morbidity, mortality andhospitalization rates in patients with systolic heartwith benefits in older (>60) as well as younger sub-groups [5, 8], although very elderly patients havegenerally been under-represented in these trials. Morerecently, spironolactone has been shown to reducemorbidity and mortality in patients with advancedsystolic heart failure when added to standard treat-ment, an effect seen in the older as well as the youngersubgroups within the trial [9].

Objective—To determine effects of dietary lipid and protein on plasma lipoprotein and free fatty acid concentrations and hepatic fatty acid synthesis during weight gain and rapid weight loss in cats. Animals—24 ovariohysterectomized cats. Procedure—Cats were fed a high energy diet until they gained 30% of their ideal body weight and then randomly assigned to receive 1 of 4 weight reduction diets (6 cats/diet) at 25% of maintenance energy requirements. Diets contained a low or high quality protein source and a lipid source deficient or sufficient in long chain essential fatty acids. Plasma samples and liver biopsy specimens were obtained before and after weight gain and during and after weight loss for determination of free fatty acid, triglyceride, and lipoprotein concentrations. Synthesis of these substances was measured by use of isotope enrichment. Results—Plasma total cholesterol concentration and concentration of lipoprotein fractions increased after weight gain, compared with baseline values. Weight loss resulted in a significant decrease in concentrations of all lipoprotein fractions except high density lipoprotein. High density lipoprotein concentration was significantly greater in cats fed diets containing an oil blend, compared with cats fed diets containing corn oil. Fatty acid synthesis after weight loss was below the detection limit of the measurement technique. Conclusions and Clinical Relevance—In cats undergoing rapid weight loss there is neither increased triglyceride synthesis nor decreased transport of very low density lipoproteins from the liver, suggesting that their involvement in the development of hepatic lipidosis may be minimal. (Am J Vet Res 2000;61:566–572)

Recently three equations for estimating gluconeogenesis in vivo have been proposed, two by J. A. Tayek and J. Katz [ Am. J. Physiol. 270 ( Endocrinol. Metab. 33): E709–E717, 1996, and Am. J. Physiol. 272 ( Endocrinol. Metab. 35): E476–E484, 1997] and one by B. R. Landau, J. Wahren, K. Ekberg, S. F. Previs, D. Yang, and H. Brunengraber [ Am. J. Physiol.274 ( Endocrinol. Metab. 37): E954–E961, 1998]. Both groups estimate gluconeogenesis from cycling of [U-13C]glucose to lactate and back to glucose, detected by mass spectrometry. Landau’s approach is based on analysis of labeled molecules, whereas Tayek and Katz’s is based on labeling of carbon atoms by use of the concept of “molar enrichment,” which weights each mass isotopomer by the number of labeled carbons. We derived an equation very similar to Landau’s using binomial probability. Our analysis demonstrates that the molecular-based approach is correct. Additionally, equations appropriate for 14C studies are not appropriate for 13C studies, because the method used to detect14C, decay of atoms, differs from13C mass isotopomers detected as labeled molecules. We conclude that the molar enrichment carbon-based approach is not useful in the derivation of equations for the polymerization of molecules detected by mass spectrometry of molecules, and we confirm the findings of Landau et al.

A novel application of an infrared-A (IR-A) radiation source equipped with a water-filter in the radiation path is described, which allows for tumour treatment with a simultaneous combination of localized hyperthermia (HT) and bacteriochlorophyll-serine (Bchl-ser) based photodynamic therapy (PDT). Using this system, the IR-A radiation was used to heat tumours to 43 degrees C for 60 min, while at the same time activating the Bchl-ser which was injected i.v. at a dose of 20 mg/kg, 10 min following commencement of HT. The growth of tumours undergoing this combined therapy was compared to that of tumours undergoing HT alone or sham-treated controls. Within the 90 day observation period, 100% of tumours in sham-treated animals, 80% in HT-treated animals and only 17% in HT + Bchlser-treated animals reached the end point target volume of 3.5 ml. Thus, the tumour growth inhibition effect of HT can be substantially enhanced by combination with Bchl-ser-PDT. This novel technique has proved to be well-tolerated, easy to apply and should be suitable for treatment of superficial malignancies, especially where hypoxic tumour areas are present.

Purpose: The use of methylxanthine derivatives has been postulated as a means of increasing tumor perfusion and thus ameliorating tumor hypoxia. The aim of this study was to quantify and compare the effects of three methylxanthine derivatives: pentoxifylline (PX), torbafylline (TB), and HWA 138 (HW) on tumor perfusion and oxygenation. Methods and Materials: Anesthetized Sprague Dawley rats with DS-sarcomas implanted subcutaneously onto the hind foot dorsum were used in this study. Mean arterial blood pressure (MABP) was measured throughout experiments. Regional red blood cell (RBC) flux was monitored using a multichannel laser Doppler device and tumor oxygenation on a more global level was assessed polarographically using an O 2 -sensitive catheter electrode. The methylxanthine derivatives were administered as a single dose intraperitoneally (for PX 50 mg/kg; for TB and HW 75 mg/kg). Results: Following drug administration, initial decreases in MABP down to 75% of baseline values were observed for all three substances. PX, HW, and TB caused initial transient reductions in mean RBC flux followed by gradual increases to values of 137 ± 27 %, 139 ± 14 %, and 122 ± 14 % respectively at t = 60 min. Following a small initial decrease upon drug administration, O 2 partial pressure (pO 2 ) rose to 160 ± 31 %, 153 ± 34 %, and 121 ± 11 % for PX, HW, and TB, respectively at t = 60 min. At the end of the observation period ( t = 90 min), increases in RBC flux and pO 2 were still evident. When individual tumors were considered, a variety of patterns (including opposing effects) for changes in RBC flux were seen, not necessarily reflected in the mean values. Thus, while the methylxanthine derivatives caused an increased average tumor perfusion, there is evidence suggesting that a redistribution of tumor blood flow occurs which may amplify preexisting heterogeneity. Conclusions: Substantial improvements in tumor oxygenation and perfusion were observed after administration of the methylxanthine derivatives. These substances may therefore be of use during tumor therapies in which the outcome may be detrimentally affected by the presence of hypoxia.

There is a large body of evidence suggesting that deficiencies in the O2 supply of tumors exist due to restrictions (i) in the O2 delivery by perfusion and/or diffusion, and (ii) in the O2 transport capacity. Whereas the former are mostly based on inadequate and heterogeneous microcirculatory functions, the latter are predominantly due to tumor-associated anemia. Possible uses and limitations of measures are discussed which can increase the microvascular O2 content and thus may preferentially serve to enhance diffusion-limited O2 availability. In addition, means are described for improving and increasing the uniformity of microcirculation thus possibly enhancing perfusion-limited O2 delivery. Reducing cellular respiration rate should be of benefit in both pathophysiological conditions. Because both types of O2 limitation coexist in solid tumors, appropriate combinations should be aimed at eradicating tumor hypoxia which is present in at least one third of cancers in the clinical setting.

The effect of localized hypothermia on microcirculatory and metabolic parameters in s.c. DS sarcomas on the hind foot dorsum of Sprague-Dawley rats was investigated. Tumours were cooled by superfusion of the tumour surface with cooled saline solution to 25 degrees C or 15 degrees C. Control tumours remained at 35 degrees C. These temperatures were maintained for 30 min. In tumour oxygenation measurements, hypothermia at 25 degrees C and 15 degrees C caused progressive decreases in the size of the fraction of pO2 measurements between 0 and 2.5 mmHg together with a reduction in pO2 variability. No significant changes in median or mean pO2 or in the fraction of pO2 measurements between 0 and 5 mmHg, and 0 and 10 mmHg were observed. Using laser Doppler flowmetry, red blood cell flux was found to decrease significantly upon 25 degrees C or 15 degrees C hypothermia treatment to 67% and 37% of starting values respectively, whereas no significant changes were seen in control tumours over the whole observation period. Viscosity was measured in blood and plasma samples over a range of temperatures and was found to increase with decreasing temperature. Assessment of tumour glucose levels showed an increased concentration of glucose following 15 degrees C hypothermia, an observation consistent with a 'slowing down' of glycolysis. No changes in lactate or adenylate phosphate levels were observed. As a way of improving tumour oxygenation, localized hypothermia may therefore be a useful means of radiosensitization.

Acetyl-L-carnitine is known as a reservoir of activated acetyl units and as a modulator of metabolic function. The objective of this study was to quantify the fate of the acetyl moiety of acetyl-L-carnitine in lipogenic pathways. Lipogenesis was studied in an adipocyte model, differentiated 3T3-L1 cells, and a hepatoma cell, HepG2 cells. Lipogenesis and ketogenesis were examined in rat hepatocytes. Both de novo synthesis and elongation of fatty acids were investigated using gas chromatography/mass spectrometry and [1,2-(13)C]acetyl-L-carnitine. Comparisons were performed with [13C]glucose and [13C]acetate. Isotopomer Spectral Analysis, a stable isotope method for differentiating between the enrichment of the precursor and the amount of synthesis was used to analyze the data. Acetyl-L-carnitine was generally less effective than acetate as a precursor for de novo lipogenesis. The effects of acetyl-L-carnitine were not identical to those of acetate plus carnitine as expected if acetyl-L-carnitine flux to acetyl CoA is controlled by carnitine acetyl transferase. Acetyl-L-carnitine (2 mM) contributed approximately 10% of the lipogenic acetyl-CoA used for synthesis and elongation as well as 6% of the ketogenic acetyl-CoA. No differences were found between the precursor enrichment for de novo lipogenesis and for elongation of saturated fatty acids. Flux of acetyl-L-carnitine to lipid was increased, not decreased, by the ATP citrate lyase inhibitor, -hydroxycitrate. In contrast, flux of glucose to lipid was dramatically decreased by this inhibitor. These results indicate that flux of acetyl-L-carnitine to lipid can bypass citrate and utilize cytosolic acetyl-CoA synthesis.

>Salmonella Typhimurium DT8 was a very rare cause of human illness in Ireland between 2000 and 2008, with only four human isolates from three patients being identified. Over a 19-month period between August 2009 and February 2011, 34 confirmed cases and one probable case of Salmonella Typhimurium DT8 were detected, all of which had an MLVA pattern 2-10-NA-12-212 or a closely related pattern. The epidemiological investigations strongly supported a link between illness and exposure to duck eggs. Moreover, S. Typhimurium with an MLVA pattern indistinguishable (or closely related) to the isolates from human cases, was identified in 22 commercial and backyard duck flocks, twelve of which were linked with known human cases. A range of control measures were taken at farm level, and advice was provided to consumers on the hygienic handling and cooking of duck eggs. Although no definitive link was established with a concurrent duck egg-related outbreak of S. Typhimurium DT8 in the United Kingdom, it seems likely that the two events were related. It may be appropriate for other countries with a tradition of consuming duck eggs to consider the need for measures to reduce the risk of similar outbreaks.

Anemia was induced in rats by the development of a hemorrhagic ascites. These animals also bore solid tumors (DS-sarcomas) on the hind foot dorsum. The effects of two methods for anemia correction on oxygenation in the solid tumors were compared in this study. Anemia was corrected either chronically by erythropoietin administration (1000 IU/kg) over 14 days (EPO) or acutely by transfusion with red blood cells (TR). Non-anemic and untreated anemic animals served as controls. Tumor oxygenation was determined in anesthetized animals using polarographic needle electrodes and pO2 histography. The reduction in hematocrit and hemoglobin content found in anemic animals could successfully be corrected either by EPO or by TR. Anemia resulted in a worsening of tumor oxygenation which could partially be reversed by EPO or TR in small tumors (1.4 ml). In larger tumors (or = 1.4 ml), neither method of anemia correction resulted in significant changes in tumor oxygenation.

Tumor oxygenation has been measured polarographically in s.c. implanted DS-sarcomas on the dorsum of the hind foot of male Sprague-Dawley rats. pO2 was determined in all 3 spatial dimensions and 3-dimensional pO2 distributions as well as the mean extent of confluent areas with pO25 mmHg were calculated. Finally, the effect of elevating arterial pO2 (by carbogen breathing) as well as of increasing tumor blood flow (by angiotensin infusion) on the spatial pO2 distribution was analyzed. Depending on the tumor volume, the spatial pO2 distribution is more or less anisotropic. In smaller tumors, areas with physiological pO2 values are found adjacent to large hypoxic areas whereas larger tumors are almost completely hypoxic/anoxic. With carbogen breathing, the mean tissue pO2 is elevated although hypoxia is not eradicated in larger tumors. In small tumors, angiotensin leads to a vasoconstriction of tumor vessels followed by a worsening of tumor oxygenation whereas in large tumors the increased systemic perfusion pressure resulted in an improvement of oxygenation. Thus, carbogen predominantly affects pO2 diffusion by increasing the arterial pO2 whereas angiotensin influences tumor perfusion and leads to an increased oxygen supply to the tumor tissue.

The effect of hyperthermia on microcirculatory and metabolic parameters in s.c. DS-sarcomas of different sizes on the hind foot dorsum of SD-rats was investigated. Hyperthermia was carried out using a novel water-filtered, infrared-A radiation technique. Heating was performed at a rate of 0.5 degrees C/min until 44 degrees C was achieved in the tumour centre, which was maintained for 60 min. Using a multichannel laser Doppler flowmeter, red blood cell flux could be assessed continuously and at several sites within the tumour tissue simultaneously. Substantial inter-site variations in laser Doppler flux (LDF) were observed during hyperthermia which were independent of tumour size, site of measurement, and temperature at the site of measurement, indicating that single site measurements of tumour LDF are poor predictors of the mean response of a tumour to hyperthermia. When mean LDF was considered, decreases in red blood cell fluxes occurred that were more pronounced the greater the tumour volume. In no case was vascular stasis observed. Hyperthermia did not affect tumour oxygenation substantially. Microregional and global assessment of lactate and ATP concentrations demonstrated increased lactate and decreased ATP levels following hyperthermia. Tumour glucose levels were increased following hyperthermia, possibly due to an enlarged distribution space resulting from development of interstitial oedema. Changes in lactate and ATP levels and the lack of changes in tumour oxygenation suggest a modification of energy metabolism following hyperthermia in the form of increased ATP hydrolysis, intensified glycolysis and impaired oxidative phosphorylation.

Cervical cancers exhibit substantial intra- and inter-tumour heterogeneities in blood flow prior to treatment, reflecting similar variability in vascularisation. When clinically relevant hyperthermia is applied as an adjuvant to established treatment modalities, blood flow may change in non-predictable directions, extents and durations, indicating subsequent variability in heat dissipation and in flow-associated parameters of the tumour microenvironment. Before heating, locally advanced cervical cancers are mostly hypoxic, acidic, exhibit substrate and energy deprivation and show lactate accumulation, which is spatially and temporally heterogeneous. Additionally a relatively homogeneous interstitial hypertension is observed. Most probably, metabolic parameters of the hostile microenvironment are able to greatly modulate the thermosensitivity of cancer cells. Adequate information concerning changes upon heat treatment is not available so far. Due to this lack of proven data for cervical cancers upon heat treatment, clinical studies are urgently needed in order to judge the possible impact of blood flow and the above-mentioned microenvironmental parameters.

Hypoxia is a characteristic of many solid tumors, can lead to the development of an aggressive phenotype and acquired treatment resistance, and is an independent, adverse prognostic indicator. In this literature review, we show that hypoxia is also a typical feature in prostate cancer (PC), the most commonly diagnosed cancer among men in most western countries. Data on blood flow (a major determinant of oxygenation status in malignancies) and on the oxygenation status (as assessed by O2-sensitive electrodes) are presented. Where possible, data on prostate cancers are compared to normal prostate (NP) tissue and benign prostate hyperplasia (BPH). The average blood flow rate in NP is 0.21 vs. 0.28 mL/g/min in BPH. Blood flow in PC is approximately three times higher than in NP (mean flow: 0.64 mL/g/min) and shows pronounced intra- and inter-tumor variability. Despite relatively high flow rates in PC, the overall mean pO2 in cancers is 6 mmHg compared to 26 mmHg in NP. As was the case with blood flow, tissue oxygenation was extremely heterogeneous with no clear dependency on a series of tumor (Gleason score, clinical size, androgen deprivation) and patient characteristics (serum PSA levels, age).

Cholesterol synthesis from 13C-labeled precursors produces a discrete spectrum of mass isotopomers detectable using gas chromatography-mass spectrometry. The isotopomer spectral analysis (ISA) method matches the observed spectrum of cholesterol isotopomers with a mathematical model to obtain the best fit of model spectrum to data spectrum. The model was based on multinomial probability expressions that simulate cholesterol synthesis as a condensation of mevalonate fragments. As many as four unknown parameters, representing fluxes between compartments, were included in the model. Models were developed to assess cholesterol synthesis from 13C-enriched precursors including mevalonate, acetate, acetoacetate or octanoate. Models were tested in the human hepatoma cell line, Hep G2, which readily incorporated the 13C substrates into cholesterol. The ISA approach was used to estimate the fractional amount of the cholesterol precursors derived from the 13C substrate and the fraction of total cellular cholesterol synthesized in the presence of the 13C substrate. The study demonstrated the feasibility of the ISA approach for a condensation biosynthesis that is not a simple polymerization and for models with more than two unknown parameters.

Metabolic characteristics of experimental hepatoma cells include elevated rates of glycolysis and lipid synthesis. However, pyruvate derived from glucose is not redily oxidized, and the source of acetyl CoA for lipid synthesis in As-39D cells has not been characterized. In this study ketone bodies were examined as a possible source of acetyl CoA in AS-30D hepatoma cells. The major findings were: 1. Acetoacetate was utilized by AS-30D cells, with 14C-lipid and 14CO2 as major products of [3-14C] acetoacetate. 2. Lipid synthesis from acetoacetate was dependent on the presence of glucose in the medium. 3. Acetoacetate supported rapid respiration by AS-30D mitochondria in the presence of 0.1 mM malate. 4. Succinyl CoA acetoacetyl CoA transferase activity in AS-30D mitochondria was approximately 40 fold greater than that found in rat liver mitochondria. 5. Addition of acetoacetate, but not beta-hydroxybutyrate decreased conversion of [1-14C] acetate to 14CO2, presumably by diluting the specific radioactivity of the acetyl CoA derived from the acetate tracer. 6. In the presence of glucose, approximately one fourth of acetoacetate utilized was converted to lipid. This result is consistent with elevated lipogenesis postulated by the truncated TCA cycle hypothesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Experiments on s.c. rat tumours (DS sarcoma) were performed to determine whether chronic or acute changes in tumour perfusion necessarily lead to changes in tissue oxygenation and bioenergetic status since, as a rule, blood flow is thought to be the ultimate determinant of the tumour bioenergetic status. Based on this study, there is clear experimental evidence that growth-related or acute (following i.v. administration of tumour necrosis factor alpha) decreases in tumour blood flow are accompanied by parallel alterations in tissue oxygenation. In contrast, tumour energy status remains stable as long as flow values do not fall below 0.4-0.5 ml g-1 min-1, and provided that glucose as the main substrate can be recruited from the enlarged interstitial compartment. Perfusion rate seems to play a paramount role in determining energy status only in low-flow tumours or low-flow tissue areas.

Tumor hypoxia is a major driving force for malignant progression since it can promote local invasion of cancer cells and metastatic spread to distant sites [1–7]. Tumor hypoxia also plays a key role in the development of acquired treatment resistance since it is capable of directly and/or indirectly conferring resistance to therapy [8, 9]. As a result, hypoxia has been shown to act as an independent, adverse prognostic factor [10–14]. Due to this seminal role of tumor hypoxia, knowledge concerning the oxygenation status of malignant tumors in terms of O2 tension distributions and detection of hypoxia are indispensable in the clinical setting. For this reason, the respective oxygenation status for gastrointestinal (GI) malignancies have been compiled in this review, together with blood flow values (where available), which are major determinants of the oxygen status. Pretherapeutic data of the following tumor entities will be presented: Cancers of the stomach, gallbladder, common bile duct, pancreas, colon, rectum, and primary and metastatic liver tumors.

We hypothesize that a complete blood count (CBC) with manual differential from umbilical cord blood is equivalent to a CBC with manual differential obtained from the neonate on admission. A CBC and manual differential was performed on 174 paired umbilical cord blood and admission blood samples from infants

Purpose : Nicotinamide has been reported to preferentially radiosensitize tumor tissue, supposedly through a reduction in tumor hypoxia. This may occur as a result of nicotinamide-induced changes in tumor blood flow and therefore the present study was undertaken to evaluate the effect of nicotinamide on circulatory parameters in skeletal muscle and tumor tissue (subcutaneously-implanted DS-sarcomas) of the rat. Methods and Materials : Mean arterial blood pressure (measured in the common carotid artery using a pressure transducer) and red blood cell flux (as measured by laser Doppler flowmetry) were continuously monitored for 120 min following a single intraperitoneal application of nicotinamide (500 mg/kg). An arterial blood pressure/laser Doppler flux ratio was estimated for tumor and muscle tissue. Results : Nicotinamide significantly reduced the mean arterial blood pressure to a minimum value 25% below the pretreatment value 20 min after the commencement of drug administration, with partial recovery thereafter. Red blood cell flux through tumor tissue, following an initial rapid decrease, rose steadily to values 34% above those measured in control animals at t = 60 min, while the arterial blood pressure/laser Doppler flux ratio in tumor tissue fell to values 34% below those of control animals. In skeletal muscle similar trends were seen although the changes were not of the same extent as those seen in tumor tissue. Tumor pO 2 was measured 60 min following i.p. application of nicotinamide using polarographic needle electrodes. Despite the significant increase in blood flow following nicotinamide, no significant difference was seen between pO 2 histograms obtained in tumors in nicotinamide treated and control animals. Conclusion : These findings suggest that nicotinamide preferentially improves tumor microcirculatory function and effectuates a decrease in the arterial blood pressure/laser Doppler flux ratio within tumor tissue, effects which reach their maximum approximately 60 min following nicotinamide administration.

The cyclic nucleotide phosphodiesterase 10A (PDE10A) is highly expressed in striatal spiny projection neurons and represents a therapeutic target for the treatment of psychotic symptoms. As reported previously [J Biol Chem 2009; 284:7606–7622], in this study PDE10A was seen to be additionally expressed in the pineal gland where the levels of PDE10A transcript display daily changes. As with the transcript, the amount of PDE10A protein was found to be under daily and seasonal regulation. The observed cyclicity in the amount of PDE10A mRNA persists under constant darkness, is blocked by constant light and is modulated by the lighting regime. It therefore appears to be driven by the master clock in the suprachiasmatic nucleus (SCN). Since adrenergic agonists and dibutyryl-cAMP induce PDE10A mRNA, the in vitro clock-dependent control of Pde10a appears to be mediated via a norepinephrine → β-adrenoceptor → cAMP/protein kinase A signaling pathway. With regard to the physiological role of PDE10A in the pineal gland, the specific PDE10A inhibitor papaverine was seen to enhance the adrenergic stimulation of the second messenger cAMP and cGMP. This indicates that PDE10A downregulates adrenergic cAMP and cGMP signaling by decreasing the half-life of both nucleotides. Consistent with its effect on cAMP, PDE10A inhibition also amplifies adrenergic induction of the cAMP-inducible gene arylalkylamine N-acetyltransferase (Aanat) which codes the rate-limiting enzyme in pineal melatonin formation. The findings of this study suggest that Pde10a expression is under circadian and seasonal regulation and plays a modulatory role in pineal signal transduction and gene expression.

Journal article The increased discharge of Tc-99 from the Sellafield plant following the commissioning of the Enhance Actinide Removal Plant in 1994 was reflected in higher Tc-99 activity concentrations over much of the Irish Sea The presence of this radionuclide in the marine environment is of concern not only because of its long half life but also high bio-concentration factor in commercially valuable species such Norway lobster (Nephrops norvegicus) and common lobster (Homarus gammarus) Accurate predictions of the transport, and spatial and temporal distributions of Tc-99 in the Irish Sea have important environmental and commercial implications In this study transport of the Tc-99 material was simulated in order to develop an increased understanding of long-term horizontal and vertical distributions In particular impact of seasonal hydrodynamic features such as the summer stratification on the surface-to-bottom Tc-99 ratio was of interest Also material retention mechanisms within the western Irish Sea were explored and flushing rates under various release conditions and meteorological forcing were estimatedThe results show that highest vertical gradients are observed between June and July in the deepest regions of the North Channel and the western Irish Sea where radionuclide-rich saline-poor water overlays radionuclide-poor saline-rich Atlantic water masses Strong correlation between top-to-bottom ratio of Tc-99 and strength of stratification was found Flushing studies demonstrate that as the stratification intensifies residence times within the western Irish Sea increase In stratified waters of the gyre Tc-99 material is flushed out from the upper layer much quicker than from the bottom zoneThe research also shows that in the gyre the biologically active upper layers above the thermocline are likely to contain higher concentrations than the near-bed region Long-term horizontal and vertical distributions as determined in this study provide a basis for assessment of a potential biota exposure to Tc-99 (C) 2010 Elsevier B V All rights reserved Radiological Protection Institute of Ireland (RPII); Environmental Protection Agency peer-reviewed

Background Although dietary ketogenic essential amino acid (KAA) content modifies accumulation of hepatic lipids, the molecular interactions between KAAs and lipid metabolism are yet to be fully elucidated. Methodology/Principal Findings We designed a diet with a high ratio (E/N) of essential amino acids (EAAs) to non-EAAs by partially replacing dietary protein with 5 major free KAAs (Leu, Ile, Val, Lys and Thr) without altering carbohydrate and fat content. This high-KAA diet was assessed for its preventive effects on diet-induced hepatic steatosis and whole-animal insulin resistance. C57B6 mice were fed with a high-fat diet, and hyperinsulinemic ob/ob mice were fed with a high-fat or high-sucrose diet. The high-KAA diet improved hepatic steatosis with decreased de novo lipogensis (DNL) fluxes as well as reduced expressions of lipogenic genes. In C57B6 mice, the high-KAA diet lowered postprandial insulin secretion and improved glucose tolerance, in association with restored expression of muscle insulin signaling proteins repressed by the high-fat diet. Lipotoxic metabolites and their synthetic fluxes were also evaluated with reference to insulin resistance. The high-KAA diet lowered muscle and liver ceramides, both by reducing dietary lipid incorporation into muscular ceramides and preventing incorporation of DNL-derived fatty acids into hepatic ceramides. Conclusion Our results indicate that dietary KAA intake improves hepatic steatosis and insulin resistance by modulating lipid synthetic pathways., National Institutes of Health (U.S) (Bioengineering Research Partnership Grant DK58533), National Institutes of Health (U.S) (NIH Metabolomics Roadmap Initiative DK070291), National Institutes of Health (U.S) (DK072856)

The hypoxia-inducible factor (HIF)-dependent transcriptional response is often very pronounced in hypoxic microregions of solid malignant tumours, leading to secretion of pro-angiogenic factors and activation of a hypoxia-tolerant, glycolytic metabolism. Here, the influence of the microenvironment of tumour-initiating cells as a factor determining intertumoural variations in the relative contributions of both processes has been examined.The oxygenation status was assessed in rat DS-sarcomas using polarographic needle electrodes. Tumours were generated by allografting cells from either normoxic cell culture or severely hypoxic/anoxic ascites. HIF-related marker expression and intercapillary distances were analysed using immunohistochemistry.Cells preconditioned in hypoxic ascites form poorly vascularised, hypoxic tumours in rats, showing strong activation of HIF-1alpha and glucose transporter (GLUT)- 1. Conversely, tumour-initiating DS-cells derived from normoxic cell culture form highly angiogenic, normoxic tumours with a significantly lower expression of HIF-1alpha and GLUT-1. Growth rates and the fraction of Ki-67 positive cells for both tumour groups were comparable.The intensity of angiogenesis in this model is primarily determined by the state of metabolic adaptation of tumour-initiating cells, rather than being a function of HIF-activation during solid tumour growth, a finding which is highly relevant for the design of treatment regimens targeting the tumour vasculature.

This study has attempted to address the controversy concerning sustained increases in tumor oxygenation upon localized mild hyperthermia. While some previous studies have reported transient increases, others have reported persistent increases in tumor oxygenation, lasting for upto 2 days after application of mild hyperthermia. In order to determine changes in oxygenation at clinically relevant tumor temperatures, experimental tumors in rats underwent localized hyperthermia at either 40, 41.8°C or 43°C for 1 h using water-filtered infrared-A irradiation. Oxygenation was continuously measured before, during and upto 60 min after hyperthermia in the tumors of anesthetized rats using oxygen-sensitive catheters. The data obtained indicate that localized hyperthermia can lead, on average to an improved tumor oxygenation, although this improvement is generally transient and no longer evident 1 h after heating. Since clinically relevant increases in oxygenation enduring beyond the heating period were rarely seen, it would appear that an improvement in the efficacy of oxygen-dependent cancer therapy is unlikely to be achieved in the post-hyperthermia period.

We developed a LC-MS-MS assay of the2H labeling of free glutathione (GSH) and bound glutathione [GSSR; which includes all DTT-reducible forms, primarily glutathione disulfide (GSSG) and mixed disulfides with proteins] and ophthalmate (an index of GSH depletion) labeled from2H-enriched body water. In rats whose body water was 2.5%2H enriched for up to 31 days, GSH labeling follows a complex pattern because of different rates of labeling of its constitutive amino acids. In rats infused with [13C2,15N-glycine]glutathione, the rate of appearance of plasma GSH was 2.1 μmol·min−1·kg−1, and the half-life of plasma GSH/GSSR was 6–8 min. In healthy humans whose body fluids were 0.5%2H enriched, the2H labeling of GSH/GSSR and ophthalmate can be precisely measured after 4 h, with GSH being more rapidly labeled than GSSR. Since plasma GSH/GSSR derives mostly from liver, this technique opens the way to 2) probe noninvasively the labeling pattern and redox status of the liver GSH system in humans and 2) assess the usefulness of ophthalmate as an index of GSH depletion.

The influence of liver hyperthermia on hepatic arterial and portal venous blood flow to tumour and normal hepatic tissue was examined in a rabbit VX2 tumour model. Hyperthermia was delivered by 2450 MHz microwave generator to exteriorized livers in 18 rabbits. Blood flow was measured in both portal vein and hepatic artery using radioactive tracer microspheres before, during and 5 min after intense (greater than 43 degrees C) hyperthermia. During hyperthermia a decrease in total liver blood flow was composed primarily of a decrease in hepatic arterial blood flow to tumour tissue. Tumours were supplied almost exclusively by the hepatic artery and thus total tumour blood flow was significantly depressed during heating. The decreased tumour blood flow persisted after the cessation of hyperthermia and was indicative of vascular collapse in the tumour tissue. Temperature differentials in tumour compared to normal tissue ranged from 5 degrees C to 8 degrees C during hyperthermia because of the lower tumour blood flow. The portal vein exerted minimal influence on temperatures attained in the tumour tissue during hyperthermia but would have mediated normal liver tissue heat loss.

Many non-surgical tumor treatments induce reactive oxygen species (ROS) which result in cell damage. This study investigated the impact of ROS induction on the expression of adhesion molecules and whether alpha-tocopherol pre-treatment could have a protective effect. Experimental rat DS-sarcomas were treated with a combination of localized 44 degrees C-hyperthermia, inspiratory hyperoxia and xanthine oxidase which together lead to a pronounced ROS induction. Further animals were pre-treated with alpha-tocopherol. The in vivo expression of E- and N-cadherin, alpha-catenin, integrins alpha v, beta 3 and beta 5 as well as of the integrin dimer alpha v beta 3 was assessed by flow cytometry. The expression of alpha v-, beta 3-integrin, of the alpha v beta 3-integrin dimer and of E-cadherin was significantly reduced by the ROS-inducing treatment. This effect was partially reversible by alpha-tocopherol, indicating that ROS play a role in this process. N-cadherin, alpha-catenin and beta 5-integrin expression were unaffected by ROS. These results indicate that the expression of several adhesion molecules is markedly reduced by ROS and may result in a decrease in the structural stability of tumor tissue. Further studies are needed to clarify the impact of ROS induction on the metastatic behavior of tumors.