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It is a widespread misconception that infants with congenital heart disease (CHD) are not able to breastfeed. The purpose of this study was to describe breastfeeding duration and outcomes among a high-risk group of infants with CHD. Mothers of 68 infants at least 6 months of age, who had experienced cardiac surgery during the neonatal period, were surveyed regarding breastfeeding and milk expression habits. Results for this sample of infants were compared to a benchmark study conducted in 1993 at the same institution that described breastfeeding outcomes for 45 infants with CHD. Improved outcomes for the 1998-2000 sample are attributed to an active lactation consultation program instituted in 1998. These findings suggest that given support and education necessary to initiate and maintain lactation, mothers can successfully breastfeed their infants with CHD for durations recommended by the Healthy People 2010 initiative. [ABSTRACT FROM AUTHOR]

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.

Background: The Child Nutrition and WIC Reauthorization Act of 2004 mandated written school wellness policies. Little evidence exists to evaluate the impact of such policies. This study assessed the quality (comprehensiveness of topics addressed and strength of wording) of wellness policies and the agreement between written district-level policies and school-reported nutrition policies and practices in 48 low-income Michigan school districts participating in the School Nutrition Advances Kids study., Method: Written wellness policy quality was assessed using the School Wellness Policy Evaluation Tool. School nutrition policies and practices were assessed using the School Environment and Policy Survey. Analysis of variance determined differences in policy quality, and Fisher's exact test examined agreement between written policies and school-reported practices., Results: Written wellness policies contained ambiguous language and addressed few practices, indicating low comprehensiveness and strength. Most districts adopted model wellness policy templates without modification, and the template used was the primary determinant of policy quality. Written wellness policies often did not reflect school-reported nutrition policies and practices., Conclusions: School health advocates should avoid assumptions that written wellness policies accurately reflect school practices. Encouraging policy template customization and stronger, more specific language may enhance wellness policy quality, ensure consistency between policy and practice, and enhance implementation of school nutrition initiatives., (© 2014 Society for Public Health Education.)

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.

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., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Schools can promote healthy eating in adolescents. This study used a qualitative approach to examine barriers and facilitators to healthy eating in schools., Methods: Case studies were conducted with 8 low-income Michigan middle schools. Interviews were conducted with 1 administrator, the food service director, and 1 member of the coordinated school health team at each school., Results: Barriers included budgetary constraints leading to low prioritization of health initiatives; availability of unhealthy competitive foods; and perceptions that students would not eat healthy foods. Schools had made improvements to foods and increased nutrition education. Support from administrators, teamwork among staff, and acknowledging student preferences facilitated positive changes. Schools with a key set of characteristics, (presence of a coordinated school health team, nutrition policies, and a school health champion) made more improvements., Conclusions: The set of key characteristics identified in successful schools may represent a school's health climate. While models of school climate have been utilized in the educational field in relation to academic outcomes, a health-specific model of school climate would be useful in guiding school health practitioners and researchers and may improve the effectiveness of interventions aimed at improving student dietary intake and other health behaviors., (© 2014, American School Health Association.)

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., (Copyright © 2013 Elsevier Inc. All rights reserved.)

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 O(2)-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 pO(2) 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).

Purpose: The gene Kcnv2 codes for the voltage-gated potassium channel subunit Kv8.2, which can coassemble with Kv2.1 subfamily members to constitute functional voltage-gated potassium channels. Mutations in the Kcnv2 gene result in a retinal disorder designated "cone dystrophy with supernormal rod response (CDSRR)," revealing that Kcnv2 is essential for visual processing and cone survival. The aim of this study was to determine whether expression of Kcnv2 and Kv2.1 is under circadian regulation and may thus contribute to the clock-driven adjustment of photoreceptor function., Methods: Expression of the genes was recorded in preparations of the whole retina and microdissected retinal neurons by using quantitative polymerase chain reaction and Western blot., Results: The transcript levels of Kcnv2 and Kv2.1 in preparations of whole retina and photoreceptor cells were found to display daily rhythms, with elevated values during the night. For Kcnv2 this rhythm was shown to evoke a corresponding rhythm in Kv8.2, the protein product of this gene. The daily changes in retinal Kcnv2 and Kv2.1 mRNA levels persisted under constant darkness and are therefore driven by the endogenous retinal clock system, which itself is entrained by light., Conclusions: The present data provide evidence that the transcriptional regulation of Kcnv2 and Kv2.1 is a way through which the retinal clock system drives the functional adaptation of visual function to the marked daily changes in environmental lighting conditions.

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.

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., (Copyright © 2011 S. Karger AG, Basel.)

Skin exposure to infrared (IR) radiation should be limited in terms of irradiance, exposure time and frequency in order to avoid acute or chronic damage. Recommendations aimed at protecting humans from the risks of skin exposure to IR (e.g. ICNIRP, ACGIH) are only defined in terms of acute effects (e.g. heat pain and cardiovascular collapse), whereas the actual exposure conditions (e.g. spectral distribution, exposure geometry, frequency and number of exposures, thermal exchange with the environment, metabolic energy production and regulatory responses) are not taken into consideration. Since the IR component of solar radiation reaching the Earth's surface is mainly IR-A, and considering the increased use of devices emitting artificially generated IR-A radiation, this radiation band is of special interest. A number of in vitro and/or in vivo investigations assessing cellular or tissue damage caused by IR-A radiation have been undertaken. While such studies are necessary for the development of safety recommendations, the results of measurements undertaken to examine the interaction between skin and IR radiation emitted from different sources presented in this study, together with the detailed examination of the literature reveals a wide spectrum of contradictory findings, which in some instances may be related to methodological shortcomings or fundamental errors in the application of physical and photobiological laws, thus highlighting the need for physically and photobiologically appropriate experiments.

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.

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 degrees C or 43 degrees 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.

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.

Tumor cells exhibit mechanisms by which chemotherapeutic drugs can be actively pumped out of the cell (e.g., p-glycoprotein pGP, MRP1), resulting in a multidrug resistant phenotype. Many human tumors show pronounced hypoxia which can result in a local ATP depletion which in turn may compromise the efficacy of these transporters. The aim of this study was therefore to assess the transport activity and expression of drug transporters under hypoxic conditions. Prostate carcinoma cells (R3327-AT1) were exposed to hypoxia (pO2 < 0.5 mmHg) for up to 24h and pump activity was determined by an efflux assay. The results showed that exposing cells to hypoxia for 3-6 h led to a moderate increase in pGP activity. After 24 h pGP activity was reduced by 44% compared to control levels. Hypoxia reduced the MRPI activity to a lesser extent (by 25%). However, the expression of pGP and MRP1 was almost independent of the medium pO2. In conclusion, pronounced hypoxia had only minor effects on the activity of drug transporters with the activity decreasing only after 12-24 h under hypoxia, possibly as a result of ATP depletion. Instead, indirect effects of hypoxia leading to extracellular acidosis seem to have a much more pronounced effect on pGP activity.

Many tumor treatment modalities such as ionizing radiation or some chemotherapy induce reactive oxygen species (ROS) resulting in therapeutic cell damage. The aim of this study was to analyze whether such ROS induction may affect the mechanical stability of solid tumor tissue by degradation of the extracellular matrix proteins or by a loss of cell adhesion molecules. Additionally, the protective impact of alpha-tocopherol treatment on these processes was studied. Experimental DS-sarcomas in rats were treated with a combination of localized 44 degrees C hyperthermia, inspiratory hyperoxia and xanthine oxidase in order to induce pronounced oxidative stress. A second group of animals were pretreated with alpha-tocopherol. The in vivo expression of E- and N-cadherin, alpha-catenin, integrins alphav, beta3 and beta5 as well as the expression of the integrin dimer alphavbeta3 were assessed by flow cytometry. The activity of the matrix metalloproteinases MMP-2 and -9 and the activity of the urokinase-type plasminogen activator (uPA) were determined by zymography. The expression of E-cadherin, the alphav-, beta3-integrin and the alphavbeta3-integrin dimer was significantly reduced by ROS induction, an effect which was at least partially reversible by alpha-tocopherol. N-cadherin, alpha-catenin and the beta5-integrin expression was not affected by ROS. In addition, MMP-2, MMP-9 and uPA activities were markedly reduced immediately after hyperthermia. Whereas 24 h later the effects on MMP-2 and -9 were no longer evident, for uPA the impact of oxidative stress became even more pronounced at this time. These results show that several processes responsible for the structural stability of the tumor tissue are affected by therapeutic ROS generation. Changes in some of the markers assessed suggested a decrease in tissue stability upon ROS induction, whereas others indicated changes which could lead to a more stable tumor cell cluster. Depending on the individual tumor entity ROS may therefore influence the mechanical stability of solid tumors and by this affect metastatic behavior.

In the microenvironment of solid growing tumors, pronounced hypoxia or extracellular acidosis is commonly found. The aim of this study was the analysis of the cytotoxic effect of different chemotherapeutic agents (cisplatin, daunorubicin, docetaxel) under these conditions in vitro. Prostate carcinoma cells (R3327-AT1) were exposed to hypoxia (pO2 < 0.5 mmHg) or extracellular acidosis (pH = 6.6) for 6h. After 3h, cytotoxic drugs were added. The cytotoxic effect was assessed by measuring caspase 3-activity (apoptosis), LDH release (necrosis) and repopulation of the cells after chemotherapy (cell death). Compared to aerobic control conditions, severe hypoxia over 6 h per se led to a slight increase in apoptosis, necrosis and cell death. With all three chemotherapeutic agents, hypoxia led to a reduced (by approx. 25%) caspase 3-activity and a marked increase in necrosis. However, the overall cytotoxicity of the drug was not affected by O2-deficiency. By contrast, during extracellular acidosis, the cytotoxic effect of daunorubicin was reduced by 40%, preferentially due to a marked reduction in apoptosis. With cisplatin and docetaxel no change in overall cell death was detected. However, for daunorubicin the tumor-pH seems to have a strong impact on cytotoxicity. With this chemotherapeutic drug the therapeutic efficacy is markedly reduced in an acidotic environment.

The metabolic microenvironment of solid tumors is characterized by an oxygen deficiency and increased anaerobic glycolysis leading to extracellular acidosis and ATP depletion, which in turn may affect other energy-dependent cellular pathways. Since many tumors overexpress active drug transporters (e.g. the p-glycoprotein) leading to a multidrug-resistant phenotype, this study analyzes the impact of the different aspects of the extracellular microenvironment (hypoxia and acidosis) on the activity and expression of the p-glycoprotein (pGP) in the human colon carcinoma cell line LS513. For up to 24 h cells were exposed to hypoxia (pO2<0.5 mmHg), an acidic extracellular environment (pH 6.6), or the combination of hypoxia and acidosis. Under hypoxic conditions (at a normal pH), the pGP activity (measured by the daunorubicin efflux) and the pGP expression were not markedly altered. Under acidic conditions, however, the pGP-mediated drug efflux was increased, an effect which was even more pronounced when the cells were exposed to hypoxia and acidosis simultaneously (increasing the pGP-activity by 70%). The cellular pGP expression remained almost constant under these conditions, indicating that the increased transport rate results from a functional modulation. The findings of the present study indicate that the parameters of the tumor microenviroment (especially extracellular acidosis) can increase the pGP-mediated drug efflux, an effect which may explain the reduced cytotoxicity of chemotherapeutic agents in hypoxic/acidic tumors.

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 (R2=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 (R2=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 low extracellular 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.

Although strong evidence is available suggesting that microenvironmental parameters play a role in lymphogenic or hematogenic metastasis, the underlying mechanisms are still unclear and further investigations of this topic are needed. For such a study however, an appropriate model of metastasis for in vivo analysis of this process would be required. An in vivo model of a solid tumor (rat DS sarcoma) has therefore been established to enable monitoring of the steps involved in tumor metastasis. Rat DS sarcoma cells were transfected with the pTracer-SV40 plasmid, containing the super-GFP and zeocin resistance genes. DS sarcoma cells showing high and stable expression of GFP (DSGFP cells) were selected by cell sorting and in vitro culturing with zeocin. To establish in vivo growth, DSGFP cells were subsequently injected intraperitoneally (i.p.) without additional selection by zeocin and GFP expression was monitored by flow cytometry. Using DSGFP ascites cells, solid tumors were implanted subcutaneously into the hind foot dorsum of rats. The expression of GFP was assayed by fluorescence microscopy. The detection of circulating DSGFP sarcoma cells in the blood was performed using the PCR technique. GFP expression in vitro was stable for more than 40 passages. Cell sorting, however, did not enable selection of a DSGFP cell population with a higher long-term stable GFP expression. After i.p. cell implantation, GFP expression in DSGFP ascites cells was maintained over at least 19 passages. Solid tumors implanted by injection of DSGFP ascites cells showed stable GFP expression. The growth rate of solid DSGFP sarcomas was slightly slower compared to that of non-transfected cell lines. The detection limit for circulating DS sarcoma cells in blood was 100 DSGFP cells/ml whole rat blood. Micrometastases in loco-regional lymph nodes, lung and liver were detectable by immunohistology and real-time PCR. This in vivo model showing stable expression of GFP could be useful for analyzing the mechanisms of metastasis, particularly where micrometastases or circulating tumor cells are to be identified.

Objective: To assess the effects of dietary supplementation using two isomeric blends of conjugated linoleic acid (CLA) on immune function in healthy human volunteers., Design: Double-blind, randomised, placebo-controlled intervention trial., Subjects and Intervention: A total of 55 healthy volunteers (n=20 males, n=35 females) were randomised into one of three study groups who received 3 g/day of a fatty acid blend containing a 50:50 cis-9, trans-11: trans-10, cis-12 CLA isomer blend (2 g CLA), and 80:20 cis-9, trans-11: trans-10, cis-12 (80:20) CLA isomer blend (1.76 g CLA) or linoleic acid (control, 2 g linoleic acid) for 8 weeks., Results: Supplementation with the 80:20 CLA isomer blend significantly (P< or =0.05) enhanced PHA-induced lymphocyte proliferation. CLA decreased basal interleukin (IL)-2 secretion (P< or =0.01) and increased PHA-induced IL-2 and tumor necrosis factor alpha (TNF(alpha)) production (P< or =0.01). However, these effects were not solely attributable to CLA as similar results were observed with linoleic acid. CLA supplementation had no significant effect on peripheral blood mononuclear cells IL-4 production, or on serum-soluble intercellular adhesion molecule-1 (sICAM-1) or plasma prostaglandin E2 (PGE2) or leukotreine B4 (LTB4) concentrations., Conclusions: This study shows that CLA supplementation had a minimal effect on the markers of human immune function. Furthermore, supplementation with CLA had no immunological benefit compared with linoleic acid.

Several non-surgical tumor treatment modalities produce their cytotoxic activity by generating reactive oxygen species (ROS). Anti-oxidative enzymes such as superoxide dismutase (SOD) or exogenously supplied antioxidants may therefore reduce the efficacy of these treatments. The aim of the present study was to analyze the impact of (i) inhibiting SOD using 2-methoxyestradiol (2-ME), or (ii) application of alpha-tocopherol, on the cellular damage induced by hyperthermia (HT) in experimental tumors. DS-sarcoma cells grew either in culture or as solid tumors subcutaneously implanted in rats. In vitro, DS-cells were incubated with 2-ME, and cell proliferation, ROS formation, lipid peroxidation and apoptosis were measured. In vivo, DS-sarcomas were treated with a ROS-generating hyperthermia combined with 2-ME or alpha-tocopherol application. Inhibition of SOD by 2-ME in vitro induced pronounced oxidative injury resulting in reduced proliferation. In vivo, ROS-generating hyperthermia led to local tumor control in 23% of the animals. The additional inhibition of SOD by 2-ME increased the control rate by approximately 50%. Application of alpha-tocopherol was found to have no effect on local tumor control, either in combination with ROS-generating hyperthermia or when 2-ME was additionally applied. Inhibition of SOD during ROS-generating hyperthermia results in pronounced cell injury and an improved local tumor control whereas exogenously applied vitamin E seems not to have an impact on oxidative stress.

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.

Objectives: To evaluate quality of life before surgery for genital cancer to determine risk factors that might influence the physician-patient relationship., Methods: From 1993 until 2003, 129 women with cervical cancer entered this prospective study. Patients were contacted 1 to 5 days before surgery by a psychologist or psychotherapeutically trained physician on the surgical ward. The semistructured interview included questions on the patient's psychosocial well-being according to criteria of the biographic interview technique. The preoperative anxiety level was evaluated by the STAI and quality of life by the Cancer Rehabilitation Evaluation System (CARES) and EORTC questionnaires. Patients were assigned to groups undergoing pelvic exenteration (n = 62) or Wertheim procedure (n = 67)., Results: The preoperative anxiety level did not correlate with the treatment modality. Women with a high anxiety level complained of a lack of information which correlated with a dissatisfaction concerning the physician-patient relationship (r = 0.457, P = 0.001). Quality of life in terms of medical interaction and the need for information were indicated to be the most important aspects for cancer patients facing genital surgery., Conclusions: These data demonstrate the need for information strategies before surgery: first, to reduce anxiety by anticipating future quality of life outcome problems and, second, to improve medical interaction before stressful treatment options.

The aim of this study was to assess the anti-tumor effect of photodynamic therapy (PDT) using a novel bacteriochlorophyll derivative, palladium-bacteriopheophorbide (TOOKAD) on tumor growth, perfusion and oxygenation. Rat DS-sarcomas were treated with either TOOKAD-PDT (2 mg/kg, i.v., immediate illumination) or one of the control treatments (sham-treatment, illumination without photosensitizer, or photosensitizer without illumination). The light source was an infrared-A irradiator fitted with appropriate filters, so that the wavelengths applied (665-800 nm) included the absorption maximum of TOOKAD at 763 nm. Tumor volume was monitored for 90 days after treatment or until a target volume (3.5 ml) was reached. TOOKAD-PDT dramatically inhibited tumor growth with 92% of tumors not reaching the target volume within the observation period. In further experiments, tumor perfusion was assessed using laser Doppler flowmetry. Upon TOOKAD-PDT treatment, a rapid, pronounced decrease in perfusion was seen, down to levels corresponding to only 3% of initial values. Tumor oxygenation monitoring revealed parallel decreases, with levels corresponding to anoxia being reached. The significant anti-tumor effects presented in this report, taken together with the chemical and pharmacokinetic properties of the novel photosensitizer TOOKAD, underline the therapeutic potential of this approach in which flow stasis and induction of anoxia are key elements.

Oxidative stress-related changes in tumors upon localized hyperthermia (HT), 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT) and their combination (ALA+HT) were examined after the observation that the antitumor effects of ALA-PDT could be significantly enhanced upon simultaneous application of HT. Rats bearing s.c. DS-sarcomas (0.6-1.0 ml) on the hind foot dorsum were anesthetized and underwent one of the following treatments: (i) ALA-PDT (375 mg/kg 5-ALA i.v.); (ii) localized HT, 43 degrees C for 60 min; (iii) combined ALA-PDT and HT [=ALA+HT]. Appropriate control experiments were also performed. After treatment, tumors were excised and rapidly frozen for later analysis of nitrosative stress (protein nitration), apoptotic events (TUNEL, caspase activation, DNA and RNA fragmentation), expression of heat shock proteins (hsp70 and HO-1), glutathione (GSH) levels and glutathione peroxidase (GPx) activity. Protein nitration was found to increase upon treatment, being especially pronounced in the ALA+HT group, and could partially be related to areas surrounding microvessels. The extent of nitrosative stress also correlated well with the appearance of the markers of apoptosis and the inhibition of in vivo tumor growth as seen in a previous study. GSH levels decreased upon treatment, the reduction being most prominent in the ALA-PDT and ALA+HT groups. GPx activity, however, showed a significant decrease only in the ALA-PDT group. Whereas hsp70 expression increased upon HT, ALA-PDT caused a decrease, and these opposing effects were nullified with ALA+HT. The results obtained point to a number of cellular mechanisms-including effects on cellular defense mechanisms and an abrogation of the heat shock defense mechanism-that may interact to achieve the potentiated tumor response rate seen in vivo upon combined treatment., (Copyright 2003 Wiley-Liss, Inc.)

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.

The possibility of enhancing aminolaevulinic acid (ALA)-based photodynamic therapy (PDT) by simultaneous application of localised hyperthermia (HT) was evaluated. Treatments of rat DS-sarcomas included: (i) control, (ii) ALA administration (375 mg kg(-1), i.p.), no illumination, (iii) 'nonthermal' illumination, (iv) ALA-PDT: that is, ALA administration, 'nonthermal' illumination, (v) localised HT, 43 degrees C, 60 min (vi) ALA-PDT+HT: ALA administration with full spectrum irradiation resulting in ALA-PDT and HT. Tumour volume was monitored for 90 days or until a target volume (3.5 ml) was reached. No differences were seen between the first three groups, with all tumours reaching the target volume by 8-11 days. A total of 13 and 15% of tumours did not reach the target volume by day 90 following HT or ALA-PDT treatment, respectively. ALA-PDT+HT showed the greatest antitumour effect (P=0.0001), with 61% of the tumours not reaching the target volume. Viability and in vitro growth were also assessed in cells from tumours excised after treatment. ALA-PDT+HT reduced the fraction of viable tumour cells by 85%, and in vitro culture showed pronounced growth delay compared to control cells. These results demonstrate an enhanced antitumour effect upon ALA+HT, which appears to involve direct cell toxicity rather than solely vascular damage.

Electrical bioimpedance spectroscopy is a fast and relatively easily applicable method for tissue characterization. In the frequency range up to 10 MHz, current conduction through tissue is mainly determined by tissue structure, i.e. the extra- and intra-cellular compartments and the insulating cell membranes. Therefore, changes in the extra- and intra-cellular fluid volumes are reflected in the impedance spectra. Investigations of tumours (DS sarcoma, implanted on the hind foot dorsum of rats) during treatment with localized hyperthermia (HT), photodynamic therapy (PDT) and the combination of these two components were carried out using impedance spectroscopy in the frequency range of 37 Hz to 3.7 MHz. Data collected reveal totally different, but characteristic, behaviour patterns for the three treatments. HT caused a slow increase in conductance at high frequencies (G(HF)) and in the extracellular space index (ECSI), indicating an increase in extracellular fluid volume and in total fluid content. With PDT, G(HF) increased immediately upon commencement of irradiation and was accompanied by a distinct decrease in ECSI, indicating the development of a pronounced intracellular oedema.

The aim of this study was to assess pivotal factors determining the oxygenation status of malignant tumors, and, for comparison, of normal tissues. For this purpose, microvascular patterns, blood flow data, O2 consumption rates and O2 extractions were correlated to the median pO2 values of isografted rodent and xenografted human tumors, and of various normal tissues. No correlations were found between median pO2 values and vascular patterns, O2 consumption rate or blood flow rate. When O2 extraction, however, was considered (a comprehensive parameter which encompasses all of the above factors), a strong inverse correlation was found between this parameter and the median pO2 values, both for malignant tumors (r2=0.917) and normal tissues (r2=0.959). At similar O2 extraction values, the median pO2 values in the solid tumors were substantially lower than those in normal tissues, a finding which most probably reflects the chaotic microcirculation found in tumors, the loss of flow regulation which in normal tissues meets the metabolic demands of the cells, and in some cases, tumor-associated anemia.

Since local hyperthermia (HT) affects microenvironmental parameters, the aim of the study was to analyze the impact of 42 degrees C-HT on microcirculatory function, tumor pO2, microregional redox status and ATP distribution in experimental rat tumors. Subcutaneously growing DS-sarcomas were treated with localized HT using infrared-A radiation resulting in a mean tumor temperature of 42 degrees C. The relative red blood cell (RBC) flux in the tumor was assessed using the laser Doppler technique and the mean tumor pO2 measured continuously using O2-sensitive catheter electrodes. In a second series of experiments, the microregional distribution of the mitochondrial redox status and ATP concentration was measured. Although the average RBC flux increased by 63%, tumor pO2 rose only by approx. 6%. No distinct changes were seen in the mitochondrial redox status. The microregional distribution of the redox status as well as of the ATP concentration showed considerable heterogeneity. In conclusion, although 42 degrees C-HT leads to a distinct improvement in tumor perfusion, there is practically no change in the oxygenation status. The latter finding can be explained by an equivalent increase in the oxygen consumption rate of the cells which increases by approx. 58% at 42 degrees C compared to normothermia.

Isolated limb perfusion allows the direct application of therapeutic agents to a tumour-bearing extremity. The present study investigated whether the dihydropyridine-type Ca(2+)-channel blocker nifedipine could improve blood flow and oxygenation status of experimental tumours during isolated limb perfusion. Perfusion was performed by cannulation of the femoral artery and vein in rats bearing DS-sarcoma on the hind foot dorsum. Perfusion rate was adjusted to maintain a perfusion pressure of 100-140 mmHg throughout the experiment. Following equilibration, nifedipine was continuously infused for 30 min (8.3 microg min(-1) kg(-1) BW). During constant-pressure isolated limb perfusion, nifedipine can significantly increase perfusion rate (+100%) and RBC flux (+60%) through experimental leg tumours. "Steal phenomena" in favour of the surrounding normal tissue and oedema formation were not observed. Despite the increased oxygen availability (+63%) seen upon application of this calcium channel blocker, nifedipine does not result in a substantial reduction of tumour hypoxia, most probably due to an increase in O(2) uptake with rising O(2) supply to the tumour-bearing hind limb. Nifedipine application during isolated limb perfusion can enhance tumour microcirculation and may therefore promote the delivery (pharmacokinetics) of anti-cancer drugs to the tumour and by this improve the efficacy of pressure-controlled isolated limb perfusion., (Copyright 2002 Cancer Research UK)

In an investigation of the antitumor effects of 2-methoxyestradiol (2-ME) in combination with other reactive oxygen generating treatments, 2-ME (0.5 microM) was found to completely inhibit cell proliferation of rat DS-sarcoma cells in vitro, with 71% of cells dying after exposure to 5 microM 2-ME. Concentration-dependent increases in ROS-formation, lipid peroxidation and mitochondrial changes were also observed, and an elevation in caspase-3 activity resulted in DNA fragmentation and apoptosis. Combination of 2-ME with hypoxanthine and xanthine oxidase enhanced in vitro cytotoxicity. In vivo, 2-ME caused a slight inhibition of tumor growth, with no tumors cured. Combination of 2-ME treatment with localized 44 degrees C hyperthermia, respiratory hyperoxia and xanthine oxidase caused a tumor growth delay with 51% of tumors cured. These results suggest that amplifying the levels of reactive oxygen species within tumor tissue with substances such as 2-ME may prove to be a promising strategy for adjuvant treatment of solid tumors.

Background and Purpose: Increasing arterial oxygen partial pressure (pO2) by breathing hyperoxic gases is an effective means of improving tumor oxygenation, although the efficacy of adding CO2 to the inspiratory gas has been discussed controversially. This study aimed at analyzing the impact of different inspiratory CO2 fractions on the time course of oxygenation and perfusion changes in experimental tumors during and after inspiratory hyperoxia., Material and Methods: Perfusion and oxygenation of rat DS-sarcomas were studied during spontaneous breathing of pure oxygen or hyperoxic gas mixtures containing different CO2 fractions (1, 2.5 or 5%). Red blood cell (RBC) flux was assessed as a measure of tumor perfusion using the laser Doppler technique and temporal changes in mean tumor pO2 were measured polarographically., Results: Mean tumor pO2 increased 3.6-fold with pure oxygen, approx. 3.3-fold when 1 or 2.5% CO2 was added and 2.7-fold during carbogen breathing. RBC flux also increased by 25-30% with all gases. With pure oxygen and with 1% CO2 (+99% O2), perfusion changes paralleled those of the mean arterial blood pressure whereas with higher CO2 fractions, a decrease in resistance to flow was observed. The differences found with the various gas mixtures were more pronounced after the end of hyperoxia. With pure oxygen, perfusion immediately returned to pretreatment values whereas with higher CO2 fractions perfusion remained elevated for at least 30 min., Conclusions: Higher inspiratory CO2 fractions (2.5 or 5%) lead to a prolonged improvement of tumor perfusion after the end of inspiratory hyperoxia when compared with pure oxygen breathing. Since no principal differences in oxygenation and perfusion were seen between the gases containing 2.5 and 5% CO2, the former may be preferable for inspiratory hyperoxia.