Sonic Hedgehog receptor Patched deficiency in astrocytes enhances glucose metabolism in mice

Objective

Astrocytes are glial cells proposed as the main Sonic hedgehog (Shh)-responsive cells in the adult brain. Their roles in mediating Shh functions are still poorly understood. In the hypothalamus, astrocytes support neuronal circuits implicated in the regulation of energy metabolism. In this study, we investigated the impact of genetic activation of Shh signaling on hypothalamic astrocytes and characterized its effects on energy metabolism.

Methods

We analyzed the distribution of gene transcripts of the Shh pathway (Ptc, Gli1, Gli2, and Gli3) in astrocytes using single molecule fluorescence in situ hybridization combined with immunohistofluorescence of Shh peptides by Western blotting in the adult mouse hypothalamus. Based on the metabolic phenotype, we characterized Glast-Cre^ERT2-YFP-Ptc^−/− (YFP-Ptc^−/−) mice and their controls over time and under a high-fat diet (HFD) to investigate the potential effects of conditional astrocytic deletion of the Shh receptor Patched (Ptc) on metabolic efficiency, insulin sensitivity, and systemic glucose metabolism. Molecular and biochemical assays were used to analyze the alteration of key pathways modulating energy metabolism, insulin sensitivity, glucose uptake, and inflammation. Primary astrocyte cultures were used to evaluate a potential role of Shh signaling in astrocytic glucose uptake.

Results

Shh peptides were the highest in the hypothalamic extracts of adult mice and a large population of hypothalamic astrocytes expressed Ptc and Gli1-3 mRNAs. Characterization of Shh signaling after conditional Ptc deletion in the YFP-Ptc^−/− mice revealed heterogeneity in hypothalamic astrocyte populations. Interestingly, activation of Shh signaling in Glast⁺ astrocytes enhanced insulin responsiveness as evidenced by glucose and insulin tolerance tests. This effect was maintained over time and associated with lower blood insulin levels and also observed under a HFD. The YFP-Ptc^−/− mice exhibited a lean phenotype with the absence of body weight gain and a marked reduction of white and brown adipose tissues accompanied by increased whole-body fatty acid oxidation. In contrast, food intake, locomotor activity, and body temperature were not altered. At the cellular level, Ptc deletion did not affect glucose uptake in primary astrocyte cultures. In the hypothalamus, activation of the astrocytic Shh pathway was associated with the upregulation of transcripts coding for the insulin receptor and liver kinase B1 (LKB1) after 4 weeks and the glucose transporter GLUT-4 after 32 weeks.

Conclusions

Here, we define hypothalamic Shh action on astrocytes as a novel master regulator of energy metabolism. In the hypothalamus, astrocytic Shh signaling could be critically involved in preventing both aging- and obesity-related metabolic disorders.

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Astrocytes exhibit differences in regulating the hedgehog signaling pathway.

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Deletion of Ptc in Glast⁺ cells prevents body weight gain and insulin resistance.

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Deletion of Ptc in Glast⁺ cells increases β oxidation.

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Central hedgehog signaling participates in the regulation of whole-body metabolism.

Interactions between antiretroviral therapy and complementary and alternative medicine: a narrative review

BACKGROUND

The use of complementary and alternative medicine including herbal medicine (phytotherapy), vitamins, minerals and food supplements is frequent among people living with HIV/AIDS (PLWHAs) who take antiretroviral (ARV) drugs, but is often not known by their prescribing physicians. Some drug-supplement combinations may result in clinically meaningful interactions.

AIMS

In this literature review, we aimed to investigate the evidence for complementary and alternative medicine interactions with ARVs.

SOURCES

A bibliographic search of all in vitro, human studies and case reports of the PubMed database was performed to assess the risk of interactions between complementary and alternative self-medication products and ARVs. The 'HIV drug interaction' (https://www.hiv-druginteractions.org) and 'Natural medicines comprehensive database' (https://naturalmedicines.therapeuticresearch.com) interaction checkers were also analysed.

CONTENT

St John's wort, some forms of garlic, grapefruit and red rice yeast are known to have significant interaction and thus should not be co-administered, or should be used with caution with certain ARV classes. Data on other plant-based supplements come from in vitro studies or very small size in vivo studies and are thus insufficient to conclude the real in vivo impact in case of concomitant administration with ARVs. Some polyvalent minerals such as calcium, magnesium, and iron salts can reduce the absorption of integrase inhibitors by chelation. Potential interactions with vitamin C and quercetin with some ARVs should be noted and efficacy and tolerance of the treatment should be monitored.

IMPLICATIONS

This review shows the importance of screening all PLWHAs for complementary and alternative medicine use to prevent treatment failure or adverse effects related to an interaction with ARVs. Further human studies are warranted to describe the clinical significance of in vitro interactions between numerous complementary and alternative medicine and ARVs.

C9C5 positive mature oligodendrocytes are a source of Sonic Hedgehog in the mouse brain

In the mature rodent brain, Sonic Hedgehog (Shh) signaling regulates stem and progenitor cell maintenance, neuronal and glial circuitry and brain repair. However, the sources and distribution of Shh mediating these effects are still poorly characterized. Here, we report in the adult mouse brain, a broad expression pattern of Shh recognized by the specific monoclonal C9C5 antibody in a subset (11–12%) of CC1⁺ mature oligodendrocytes that do not express carbonic anhydrase II. These cells express also Olig2 and Sox10, two oligodendrocyte lineage-specific markers, but not PDGFRα, a marker of oligodendrocyte progenitors. In agreement with oligodendroglial cells being a source of Shh in the adult mouse brain, we identify Shh transcripts by single molecule fluorescent in situ hybridization in a subset of cells expressing Olig2 and Sox10 mRNAs. These findings also reveal that Shh expression is more extensive than originally reported. The Shh-C9C5-associated signal labels the oligodendroglial cell body and decorates by intense puncta the processes. C9C5⁺ cells are distributed in a grid-like manner. They constitute small units that could deliver locally Shh to its receptor Patched expressed in GFAP⁺ and S100β⁺ astrocytes, and in HuC/D⁺ neurons as shown in Ptc^LacZ/+ reporter mice. Postnatally, C9C5 immunoreactivity overlaps the myelination peak that occurs between P10 and P20 and is down regulated during ageing. Thus, our data suggest that C9C5⁺CC1⁺ oligodendroglial cells are a source of Shh in the mouse postnatal brain.

MRT-92 inhibits Hedgehog signaling by blocking overlapping binding sites in the transmembrane domain of the Smoothened receptor

The Smoothened (Smo) receptor, a member of class F G protein-coupled receptors, is the main transducer of the Hedgehog (Hh) signaling pathway implicated in a wide range of developmental and adult processes. Smo is the target of anticancer drugs that bind to a long and narrow cavity in the 7-transmembrane (7TM) domain. X-ray structures of human Smo (hSmo) bound to several ligands have revealed 2 types of 7TM-directed antagonists: those binding mostly to extracellular loops (site 1, e.g., LY2940680) and those penetrating deeply in the 7TM cavity (site 2, e.g., SANT-1). Here we report the development of the acylguanidine MRT-92, which displays subnanomolar antagonist activity against Smo in various Hh cell-based assays. MRT-92 inhibits rodent cerebellar granule cell proliferation induced by Hh pathway activation through pharmacologic (half maximal inhibitory concentration [IC50] = 0.4 nM) or genetic manipulation. Using [(3)H]MRT-92 (Kd = 0.3 nM for hSmo), we created a comprehensive framework for the interaction of small molecule modulators with hSmo and for understanding chemoresistance linked to hSmo mutations. Guided by molecular docking and site-directed mutagenesis data, our work convincingly confirms that MRT-92 simultaneously recognized and occupied both sites 1 and 2. Our data demonstrate the existence of a third type of Smo antagonists, those entirely filling the Smo binding cavity from the upper extracellular part to the lower cytoplasmic-proximal subpocket. Our studies should help design novel potent Smo antagonists and more effective therapeutic strategies for treating Hh-linked cancers and associated chemoresistance.

Assessment of patient adherence to anti-infective treatment after returning home

OBJECTIVE

The lack of patient adherence to medical treatment has become a major concern for healthcare professionals. The World Health Organization estimated patient adherence to treatment at 50% only. The inadequate use of antibiotics can cause bacterial resistance the progression of which reduces therapeutic alternatives. The objective of this pilot study was to assess the patient's adherence to anti-infective agents prescribed for acute infection, after returning home.

METHOD

Thirty-seven patients hospitalized in the Infectious and Tropical Diseases unit were included. Their adherence to anti-infective drugs was assessed indirectly through data collected by calling the pharmacy and the patient in the week following discontinuation of anti-infective treatment.

RESULTS

Sixteen patients were identified as non-adherent (43.2%). A single patient could have several behaviors: extension of treatment (50%), dose modification (6.3%), voluntary omission (12.5%), and involuntary (6.3%). One patient (6.3%) did not take his anti-infective treatment. There was no major cause of non-adherence; every patient had his own reasons. The comparison of several criteria between adherent and non-adherent patients did not reveal any predictive risk factors.

CONCLUSION

Our study results revealed for the first time that 50% of patients were adherent to anti-infective agents, after returning home. They confirm the need to implement preventive actions such as a discharge pharmaceutical consultation.

It's plain and simple: transparency is good for science and in the public interest

In the past couple of years, there has been a growing focus on the need to make scientific output accessible to a greater number of people, especially in the field of clinical research. The public are being urged to become more well-informed and to ask their doctors about taking part in clinical trials.

A key finding of a report from the Association of Medical Research Charities was that all published scientific papers would benefit from having a section in plain English. Researchers running a clinical trial are expected to provide a summary of their intended research at various stages of the research process. However, there is evidence that existing summaries are of variable length and quality and not always in plain English.

As a result, the National Institute for Health Research (NIHR) commissioned a review of the guidance that is available to researchers. However, recent initiatives demonstrate that there are still a number of challenges in making current research both accessible and understandable by prospective participants.

BioMed Central also has a number of ongoing initiatives involving trial registration services and journals.

[Detection of colorectal findings for cancer prevention by immunochemical stool test with different sensitivity levels]

Immunochemical stool blood tests have a significantly higher sensitivity for the detection of advanced neoplasia and colorectal cancer. Based on national and international studies it has been required to include them into the national cancer screening programme in Germany also. The sensitivity (detection limit) can be set by the manufacturer in order to achieve an optimal and balanced result between sensitivity and specificity. The present study was conducted with 639 patients who have undergone both the screening colonoscopy, as well as the immunochemical stool blood test. The test "immoCARE-C" provided by the company CARE diagnostica Laborreagenzien GmbH was used in the study. The test has been evaluated with seven levels of detection limits between 500  ng/mL and 25  ng/mL. The best sensitivity for detection of advanced lesions was demonstrated by a cut-off of 50 ng/mL and 25  ng/mL. The specificity did not fall below 90  %. These positive results lead to considerations to organise a primary access to such tests in the prevention of colorectal cancer as a kind of filter before offering the screening colonoscopy.

Impact of fruit and vegetable vouchers and dietary advice on fruit and vegetable intake in a low-income population

BACKGROUND/OBJECTIVES

Lower-income subgroups consume fewer servings of fruit and vegetables (FVs) compared with their more advantaged counterparts. To overcome financial barriers, FV voucher delivery has been proposed.

SUBJECTS/METHODS

In a 12-month trial, 302 low-income adults 18-60 years old (defined by evaluation of deprivation and inequalities in health examination centers, a specific deprivation score) were randomized into two groups: dietary advice alone ('advice'), or dietary advice plus FV vouchers ('FV vouchers') (10-40 euros/month) exchangeable for fresh fruits and vegetables. Self-reported data were collected on FV consumption and socioeconomic status at baseline, 3, 9 and 12 months. Anthropometric and blood pressure measurements were conducted at these periods, as well as blood samples obtained for determination of vitamins. Descriptive analyses, multiple linear regression and logistic regression were performed to evaluate the impact of FV.

RESULTS

Between baseline and 3-month follow-up, mean FV consumption increased significantly in both the 'advice' (0.62±1.29 times/day, P=0.0004) and 'FV vouchers' groups (0.74±1.90, P=0.002), with no difference between groups. Subjects in the FV vouchers group had significantly decreased risk of low FV consumption (<1 time/day) compared with those in the advice group (P=0.008). No change was noted in vitamin levels (vitamin C and β-carotene). The high number of lost-to-follow-up cases did not permit analysis at 9 or 12 months.

CONCLUSION

In the low-income population, FV voucher delivery decreased the proportion of low FV consumers at 3 months. Longer-term studies are needed to assess their impact on nutritional status.

The ISRCTN Register: achievements and challenges 8 years on

The ISRCTN register has been operational for the past 8 years and is approaching 10,000 trial records. It complies with international guidelines and pools its data in the International Trial Search Portal initiated by the World Health Organisation. Through its ongoing collaboration with the Department of Health in England, the register has been able to participate in a national initiative aiming to bring clinical trials to the attention of a wider public with the objective of maximising participation. As part of BioMed Central, the register provides the first step in the concept of threaded publications, enabling the tracking of clinical research studies from inception and the linking of all resulting publications including the raw data where this is available.

Molecular determinants of non-competitive antagonist binding to the mouse GPRC6A receptor

GPRC6A displays high sequence homology to the Ca2+-sensing receptor (CaSR). Here we report that the calcimimetic Calindol and the calcilytic NPS2143 antagonize increases in inositol phosphate elicited by L-ornithine-induced activation of mouse GPRC6A after transient coexpression with Galpha(qG66D) in HEK293 cells. The calcilytic Calhex 231 did not modulate this response. A three-dimensional model of the GPRC6A seven transmembrane domains (TMs) was constructed. It was used to identify seven residues strictly conserved within the CaSR and GPRC6A allosteric binding pockets, and previously demonstrated to interact with calcilytics or calcimimetics. The mutations F666A(3.32), F670A(3.36), W797A(6.48) caused a loss of L-ornithine ability to activate GPRC6A mutants. The F800A(6.51) mutant was not implicated in either Calindol or NPS 2143 recognition. The E816Q(7.39) mutation led to a loss of Calindol antagonist activity but was without effect on NPS2143 inhibitory response. In summary, these data suggest that Calindol is primarily anchored through an H-bond to E816(7.39) in TM7 and highlight important local differences at the level of the CaSR and GPRC6A allosteric binding pockets. We have identified the first antagonists of GPRC6A that could represent new tools to analyze GPRC6A functions and serve as chemical leads for the development of more specific modulators.

Virtual screening-based discovery and mechanistic characterization of the acylthiourea MRT-10 family as smoothened antagonists

The seven-transmembrane receptor Smoothened (Smo) is the major component involved in signal transduction of the Hedgehog (Hh) morphogens. Smo inhibitors represent a promising alternative for the treatment of several types of cancers linked to abnormal Hh signaling. Here, on the basis of experimental data, we generated and validated a pharmacophoric model for Smo inhibitors constituted by three hydrogen bond acceptor groups and three hydrophobic regions. We used this model for the virtual screening of a library of commercially available compounds. Visual and structural criteria allowed the selection of 20 top scoring ligands, and an acylthiourea, N-(3-benzamidophenylcarbamothioyl)-3,4,5-trimethoxybenzamide (MRT-10), was identified and characterized as a Smo antagonist. The corresponding acylurea, N-(3-benzamidophenylcarbamoyl)-3,4,5-trimethoxybenzamide (MRT-14), was synthesized and shown to display, in various Hh assays, an inhibitory potency comparable to or greater than that of reference Smo antagonists cyclopamine and N-((3S,5S)-1-(benzo[d][1,3]dioxol-5-ylmethyl)-5-(piperazine-1-carbonyl)pyrrolidin-3-yl)-N-(3-methoxybenzyl)-3,3-dimethylbutanamide (Cur61414). Focused virtual screening of the same library further identified five additional related antagonists. MRT-10 and MRT-14 constitute the first members of novel families of Smo antagonists. The described virtual screening approach is aimed at identifying novel modulators of Smo and of other G-protein coupled receptors.

Fasting plasma carotenoids concentrations in Crohn's and pancreatic cancer patients compared to control subjects

Carotenoids are colored molecules that are widespread in the plant kingdom, but animals cannot synthesize them. Carotenes are long, apolar molecules which require fully functioning digestive processes to be absorbed properly. Hence they could be interesting markers of intestinal absorption and digestion. Indeed, only few tests are available to assess these processes and only the D-xylose tolerance test is routinely used. However D-xylose is a sugar that tests only the absorption of water-soluble compounds and it only tests duodenal absorption. In this study, we have evaluated carotenoids as markers of digestion and absorption. We compared fasting plasma carotenoids concentrations in 21 control subjects, 20 patients with Crohn's disease, and 18 patients with pancreatic cancer. Crohn's disease alters intestinal absorption while pancreatic cancer decreases pancreatic enzyme secretion thus impairing digestion. Results show that all carotenoids are significantly lower in Crohn's and cancer patients as compared to control subjects and the multifactorial analysis shows that this decrease is mostly independent of dietary intake. Interestingly, maldigestion as seen in pancreatic cancer more strongly influences plasma lutein and lycopene concentrations while malabsorption in Crohn's disease acts on other carotenoids. Thus carotenoids could be interesting alternatives for testing and following patients that are suspected of having malabsorption or maldigestion syndromes.

Factors influencing blood concentration of retinol, alpha-tocopherol, vitamin C, and beta-carotene in the French participants of the SU.VI.MAX trial

OBJECTIVES

The data was collected during the inclusion step of the SUpplémentation en VItamines et Minéraux AntioXydants (SU.VI.MAX) study. This article deals with the study's first stage before any supplementation. The collected data shows factors influencing blood vitamin concentrations and may reflect the vitamin status of volunteers.

MATERIAL AND METHODS

A total of 12,741 volunteers were enrolled in the SU.VI.MAX study 7,713 women 35-60 years of age and 5,028 men 50-60 years of age. The serum concentrations of retinol, alpha-tocopherol, and beta-carotene were measured by HPLC, and vitamin C concentration was measured by spectrofluorimetry using a Technicon continuous flow analysis apparatus. The volunteers recorded their 24 h diet by means of a specific terminal that was connected to the main central computer of the SU.VI.MAX study. Volunteers recorded the food they consumed daily and estimated its quantity by comparing pictures of dishes.

RESULTS

Retinol concentration was significantly higher in older volunteers, and was higher in male than in female volunteers. Smoking had no effect on serum retinol, but the latter was higher in the autumn than in the winter. Serum retinol concentrations were higher in the Southwest region and lower in the Ile-de-France and East-Centre regions. Serum alpha-tocopherol was slightly higher in older volunteers and also higher in male volunteers. Serum alpha-tocopherol was significantly lower in smokers, and former smokers showed intermediate levels. Like retinol, serum alpha-tocopherol was higher in the autumn, and higher in the Southwest as compared to the East-Centre Serum beta-carotene was slightly higher in younger volunteers, and concentrations were higher in female than in male volunteers. Tobacco smoking decreased serum beta-carotene, which was higher in the autumn, and higher in the East, West, and North regions. Serum vitamin C was higher in female volunteers, and was not age related. Serum vitamin C was lower in smokers, was season-dependant, but contrary to fat-soluble vitamins, concentrations were higher in the winter and spring. Serum vitamin C was higher in the Southeast and East-Centre, but lower in the North region.

CONCLUSION

These results suggest that serum retinol concentrations depend on gender, age, seasons, and location of residence. Similarly, serum alpha-tocopherol concentrations were slightly influenced by age, but more by tobacco smoking, seasons, dietary intake, and location of residence. Serum concentrations of beta-carotene depend on gender, age, smoking status, dietary intake, and location of residence. Serum vitamin C concentrations depend on gender, age, smoking status, seasons, dietary intake, and location of residence. Contrary to beta-carotene, retinol concentrations were higher in male than in female volunteers. Such a reversed relation suggests a higher beta-carotene-retinol conversion in male volunteers.

Serum concentrations of beta-carotene, vitamins C and E, zinc and selenium are influenced by sex, age, diet, smoking status, alcohol consumption and corpulence in a general French adult population

OBJECTIVE

To assess relationships between energy, nutrient and food intakes, alcohol consumption, smoking status and body mass index (BMI), and serum concentrations of beta-carotene, alpha-tocopherol, vitamin C, selenium and zinc.

METHODS

Data on health status, alcohol consumption, smoking habits, anthropometric data and biochemical measurements were obtained in 1821 women aged 35-60 y and 1307 men aged 45-60 y, participant to the SU.VI.MAX Study. Data on dietary intake were available on a subsample who reported six 24-h dietary records during the first 18 months of the study.

RESULTS

Women had higher baseline serum beta-carotene and vitamin C concentrations and lower concentration for serum vitamin E, zinc and selenium than men. In women, younger age was associated with lowered mean concentration of serum beta-carotene, vitamin E and selenium. In men, only differences were observed for serum zinc, which was lower in older men. Current smokers of both sexes had significantly lower concentrations of serum beta-carotene, vitamin C and selenium, and, only in women, of vitamin E, than nonsmokers. Alcohol consumers had lower concentrations of serum beta-carotene and higher selenium concentrations. Serum beta-carotene and vitamin C concentrations were lower in obese subjects. There were positive associations of dietary beta-carotene, vitamin C and E with their serum concentrations. Age, nutrient and alcohol intakes, serum cholesterol, BMI and smoking status explained 15.2% of the variance of serum beta-carotene in men and 13.9% in women, and 10.8 and 10.0% for serum vitamin C, and 26.3 and 28.6% for serum vitamin E, respectively.

CONCLUSION

Serum antioxidant nutrient concentrations are primarily influenced by sex, age, obesity, tobacco smoking, alcohol consumption and especially dietary intake of those antioxidant nutrients.

[Recent knowledge about intestinal absorption and cleavage of carotenoids]

Our knowledge about intestinal absorption and cleavage of carotenoids has rapidly grown during the last years. New facts about carotenoid absorption have emerged while some controversies about cleavage are close to end. The knowledge of the absorption and conversion processes is indispensable to understand and interpret the perturbations that can occur in the metabolism of carotenoids and vitamin A. Recently, it has been shown that the absorption of certain carotenoids is not passive - as believed for a long time - but is a facilitated process that requires, at least for lutein, the class B-type 1 scavenger receptor (SR-B1). Various epidemiological and clinical studies have shown wide variations in carotenoid absorption from one subject to another, such differences are now explained by the structure of the concerned carotenoid, by the nature of the food that is absorbed with the carotenoid, by diverse exogenous factors like the intake of medicines or interfering components, by diet factors, by genetic factors, and by the nutritional status of the subject. Recently, the precise mechanism of beta-carotene cleavage by betabeta-carotene 15,15' monooxygenase (EC 1.14.99.36) - formerly called beta-carotene 15,15' dioxygenase (ex EC 1.13.11.21) - has been discovered, and a second enzyme which cleaves asymmetrically the beta-carotene molecule has been found. beta-carotene 15,15' monooxygenase only acts on the 15,15' bond, thus forming two molecules of retinal from one molecule of beta-carotene by central cleavage. Even though the betabeta-carotene 15,15' monooxygenase is much more active on the beta-carotene molecule, a study has shown that it can act on all carotenoids. Searchers now agree that other enzymes that can catalyse an eccentric cleavage of carotenoids probably exist, but under physiological conditions the betabeta-carotene 15,15' monooxygenase is by far the most active, and it is mainly effective in the small bowel mucosa and in the liver. However the conversion of provitamin A carotenoids into vitamin A is only partial, and requires a satisfactory protein status.

Hedgehog interacting protein in the mature brain: membrane-associated and soluble forms

Hedgehog interacting protein (Hip) is considered as a membrane protein implicated in sequestering the hedgehog (hh) morphogens during embryonic development. Here, we demonstrate that Hip transcription also occurs in cells scattered in discrete brain areas of adult rodents and we identify the presence of membrane-associated and soluble forms of Hip in the mature brain. Moreover, we show that soluble forms of Hip, present in the conditioned medium of HEK293 cells overexpressing Hip, inhibit Sonic hedgehog (Shh)-induced differentiation of C3H10T1/2 cells, a well-characterised response associated with Shh signalling. After transfection in HEK293 cells, Hip partitions with the raft component ganglioside GM1 during density gradient centrifugation. Analysis of tagged Hip constructs reveals that the putative transmembrane domain of Hip is not cleaved suggesting that other mechanisms are implicated in the release of its soluble forms. Taken together, these data are consistent with the involvement of both membrane-associated and soluble Hip in the regulation of Shh signalling in adult neural tissues.

Assessment of DNA damage by comet assay on frozen total blood: method and evaluation in smokers and non-smokers

This study was undertaken with the aim to develop an optimised protocol for the evaluation of DNA damage in frozen whole blood. This was achieved by use of the single-cell gel electrophoresis (SCGE) or comet assay in its alkaline version. After collection of blood, the total blood sample was mixed with dimethyl sulfoxide (DMSO), a cryoprotectant commonly used for prevention of freezing-induced damage to living cells, and then stored at -80 degrees C. We observed no statistically significant differences in the level of DNA damage between fresh blood samples and frozen blood samples, as assessed by the comet assay. Considering the absence of effects of the freezing step, a frozen blood sample was included as a control sample in subsequent experiments. Thus the protocol was applied to blood samples of twenty healthy subjects including smokers and non-smokers. The comparative analysis indicated that the level of DNA damage was 56% higher in smokers than in non-smokers (P = 0.01). Altogether, this study strongly suggests that frozen whole blood could be utilised in association with the comet assay in human epidemiological bio-monitoring for the assessment of genetic damage in populations at risk.

Effects of a combined micronutrient supplementation on maternal biological status and newborn anthropometrics measurements: a randomized double-blind, placebo-controlled trial in apparently healthy pregnant women

OBJECTIVE

To investigate the possible beneficial effects of a micronutrient supplementation to apparently healthy pregnant women on maternal biological status and new born anthropometric characteristics.

SETTING

Departments of Obstetric of the University Hospital of Grenoble (France) and Lyon (France), Laboratoire of Biology of Oxidative Stress, UFR de Pharmacie. Grenoble (France).

STUDY DESIGN

Double-blind, randomized placebo-controlled intervention trial.

SUBJECTS

A total of 100 apparently healthy pregnant women were recruited at 14+/-2 weeks of gestation to delivery. At the end, they were 65 women to follow out the study.

INTERVENTIONS

Daily consumption over gestation of a micronutrients supplement or placebo.

MAIN OUTCOME MEASURES

Plasma micronutrient levels and oxidative stress parameters were measured in mothers at 14 and 38 weeks of gestation. New born's anthropometric characteristics were measured at delivery.

RESULTS

In the supplemented group, folic acid, vitamin C, E, B2, B6 and beta-carotene levels were higher than in the placebo group. Oxidative stress parameters were not different between the groups. Birth weights were increased by 10% and the number of low newborn weights (<2700 g) decreased significantly when the mother received the supplementation. Maternal plasma Zn levels were positively correlated to the newborn heights.

CONCLUSION

A regular intake of a micronutrient supplement at nutritional dose may be sufficient to improve micronutrient status of apparently healthy pregnant women and could prevent low birth weight of newborn.

Increased lipid peroxidation in pregnant women after iron and vitamin C supplementation

Iron overload could promote the generation of free radicals and result in deleterious cellular damages. A physiological increase of oxidative stress has been observed in pregnancy. A routine iron supplement, especially a combined iron and vitamin C supplementation, without biological justifications (low hemoglobin [Hb] and iron stores) could therefore aggravate this oxidative risk. We investigated the effect of a daily combined iron supplementation (100 mg/d as fumarate) and vitamin C (500 mg/d as ascorbate) for the third trimester of pregnancy on lipid peroxidation (plasma TBARS), antioxidant micronutriments (Zn, Se, retinol, vitamin E, (beta-carotene) and antioxidant metalloenzymes (RBC Cu-Zn SOD and Se-GPX). The iron-supplemented group (n = 27) was compared to a control group (n = 27), age and number of pregnancies matched. At delivery, all the women exhibited normal Hb and ferritin values. In the supplemented group, plasma iron level was higher than in the control group (26.90 +/- 5.52 mmol/L) and TBARs plasma levels were significantly enhanced (p < 0.05) (3.62 +/- 0.36 vs 3.01 +/- 0.37 mmol/L). No significant changes were observed in plasma trace elements and red blood cell antioxidant metalloenzymes. Furthermore, the alpha-tocopherol plasma level was lowered in the iron-supplemented groups, suggesting an increased utilization of vitamin E. These data show that pharmalogical doses of iron, associated with high vitamin C intakes, can result in uncontrolled lipid peroxidation. This is predictive of adverse effects for the mother and the fetus. This study illustrates the potential harmful effects of iron supplementation when prescribed only on the assumption of anemia and not on the bases of biological criteria.

High expression and anterograde axonal transport of aminoterminal sonic hedgehog in the adult hamster brain

Sonic hedgehog (SHH) is considered to play an important role in tissue induction and patterning during development, particularly in determining neuronal cell fate in the ventral neural tube and in the embryonic forebrain. SHH precursor is autoproteolytically cleaved to an aminoterminal fragment (SHHN) which retains all known SHH biological activities. Here, we demonstrate the expression of a 22-kDa SHHN immunoreactive peptide in developing and adult hamster brain regions using a rabbit antiserum directed against a mouse SHHN fragment. Interestingly, SHHN was developmentally regulated with the highest expression observed in the adult brain, was resistant to Triton X-100 solubilization at 4 degrees C and partitioned with the raft component ganglioside GM1 during density gradient centrifugation. In rat brain, Shh transcripts were identified by double in situ hybridization in GABAergic neurons located in various basal forebrain nuclei including globus pallidus, ventral pallidum, medial septum-diagonal band complex, magnocellular preoptic nucleus and in cerebellar Purkinje cells as well as in motoneurons of several cranial nerve nuclei and of the spinal cord. We show that radiolabelled SHHN peptides are synthesized in the adult hamster retina and are transported axonally along the optic nerve to the superior colliculus in vivo. Our data indicate that SHHN is associated with cholesterol rich raft-like microdomains and anterogradely transported in the adult brain, and suggest that the roles of this extracellular protein are more diverse than originally thought.

Blood micronutrients in Algeria, relationships with sex and age

Despite trace elements and vitamins are major public health problems in some African countries, there are few studies reporting micronutrient status in North Africa. Therefore, it could be interesting to evaluate plasma concentrations of vitamin A, E and beta-cartene, along with zinc, copper, selenium erythrocyte glutathione peroxidase and superoxide dismutase in Algeria. Volunteers were randomly recruited in Constantine, Batna and Mila. Vitamins, trace elements and enzymes were measured in the University Hospital of Grenoble. 455 persons were included in the study. Subjects were divided in 3 groups: group I: 15 girls and 12 boys who were 6 to 12.9 years old, group II: 190 women and 192 men 13 to 49.9 years old, group III: 24 women and 24 men 50 to 65 years old. Plasma concentrations of micronutrients and enzymes are close to those commonly observed in Europe, except for vitamin A concentrations. Indeed, retinol levels are 30-35% lower than those reported in European countries, moreover almost 8% of the population showed retinol concentrations less than 1.05 mumol/l. beta-Carotene levels were also lower than in the French average population. Ten per cent of the population had plasma zinc levels lower than 10.6 mumol/l. Vitamin E, copper and selenium status seems satisfactory in Algeria. Vitamin A is not a public health problem, however a significant percentage of residents exhibits impaired vitamin A levels and may benefit from retinol supplementation. Larger studies are needed, and particularly in children, to detect possible higher prevalence of vitamin A deficiency in poor socio-economical classes and in inner geographic areas.

Selenium status in an iodine deficient population of the West Ivory Coast

Selenium is an essential trace element which is part of the active site of seleno-dependent glutathione peroxidase and type 1 deiodinase. Therefore, it plays a key role in thyroid hormone metabolism. The present work was undertaken in order to evaluate selenium status in two Ivory Coast populations: the first with high (Glanlé) and the second with low (Abidjan) prevalence of iodine deficiency. Selenium, glutathione peroxidase, glutathione reductase, glutathione and diglutathione were determined in blood and/or urine. In plasma and erythrocytes, selenium and glutathione peroxidase were dramatically low in Glanlé. Compared to Abidjan, selenium, glutathione peroxidase, vitamin E and riboflavin status were decreased whereas diglutathione was increased in Glanlé. The results clearly demonstrate a selenium deficiency and suggest an oxidant stress in Glanlé. Causes and consequences of this selenium deficiency and oxidant stress remain to be determined.

Effect of two years' supplementation with natural antioxidants on vitamin and trace element status biomarkers: preliminary data of the SU.VI.MAX study

The "SUpplementation en VItamines et Minéraux AntioXidants" (SU.VI.MAX) study is a randomized double-blind, placebo controlled, primary-prevention trial designed to test the efficacy of a daily supplementation with antioxidant vitamins (vitamin C, 120 mg; vitamin E, 30 mg; and beta-carotene, 6 mg) and minerals (selenium, 100 microg; and zinc, 20 mg) at nutritional doses (one to three times the daily recommended dietary allowances), in reducing the frequency of cancers and cardiovascular diseases. The study involves 12,735 eligible subjects (women aged 35-60 years, men aged 45-60 years) included in 1994 in France. They will be followed up for 8 years. The targeted population is the general population. The aim of this specific analysis is to assess the effect of 2 years of supplementation on biochemical indicators of vitamin and trace element on a subsample of 1000 subjects. The mean (+/- standard deviation) concentrations of plasma beta-carotene, alpha-tocopherol, vitamin C, selenium and zinc among participants who were randomly assigned to receive a daily supplementation with beta-carotene, vitamin E, vitamin C, selenium and zinc for 2 years were significantly higher than those who were assigned to receive placebo. Specifically, the mean concentrations among men in the intervention group were 0.86 +/- 0.70 micromol/L for beta-carotene, 35.3 +/- 9.3 micromol/L for alpha-tocopherol, 11.5 +/- 4.7 microg/ mL for vitamin C, 1.65 +/- 0.33 micromol/L for selenium, and 16.2 +/- 3.9 micromol/L for zinc. The mean concentrations among women in the intervention were 1.25 +/- 0.90 micromol/L for beta-carotene, 34.9 +/- 8.4 micromol/L for alpha-tocopherol, 12.6 +/- 4.0 microg/mL for vitamin C, 1.68 +/- 0.37 micromol/L for selenium, and 15.3 +/- 3.9 micromol/L for zinc. The values observed for beta-carotene and vitamin E in the supplementation group after 2 years of intervention are those that have been associated with the lowest risk of cancer in observational studies. They are definitely lower than concentrations reported in intervention studies showing an apparent negative effect of high levels of beta-carotene supplementation on the lung cancer incidence rate in high-risk subjects (initial level multiplied by 12-18). Data from the follow-up will ascertain if any plausible reduction in the incidence rate of cancers may be associated with such amounts of antioxidant agents.

N1-Arylsulfonyl-N2-(1-aryl)ethyl-3-phenylpropane-1,2-diamines as novel calcimimetics acting on the calcium sensing receptor

The synthesis and calcimimetic properties of N1-arylsulfonyl-N2-(1-aryl)ethyl-3-phenylpropane-1,2-diamines are described. The most active compound of the series (3n, used at 10 microM) produced 97+/-11% of the maximal stimulation of [3H]IP production obtained by 10 mM Ca2+ in CHO cells expressing the calcium sensing receptor (CaSR). This calcimimetic activity was due to a specific interaction of this compound with the CaSR.

[Measurement of carotenoids by high pressure liquid chromatography: from difficulties to solutions]

The measurement of serum carotenoids by HPLC has been largely improved during the last 10 years. However these techniques still require much time and skills, and direct application of published methods is rarely satisfying. We report here the difficulties that we met to transfer some HPLC methods described in the literature to our laboratories. We propose some solution to overcome the problems that we have encountered, our experience will perhaps help out other biologists. We reported also some results obtained in healthy populations.

Discrete localizations of hedgehog signalling components in the developing and adult rat nervous system

Sonic hedgehog (Shh), a morphogen molecule implicated in embryonic tissue patterning, displays inductive, proliferative, neurotrophic and neuroprotective activities on various neural cells. Shh might exert its biological functions through binding to patched (Ptc) associated with smoothened (Smo), leading to downstream activation of target genes such as the transcription factor Gli1. We have performed a detailed localization of cells expressing transcripts of Shh, Ptc, Smo and Gli1 in brain and spinal cord of the adult rat as well as in the developing cerebellum. In the adult, Shh-positive cells were mainly observed in forebrain structures, in the Purkinje cells of the cerebellum and in motor neurons. Ptc-positive cells were frequently observed in brain areas devoid of any Shh transcripts, except in the median eminence or the facial nucleus, suggesting local Shh signalling. Interestingly, Smo transcripts were predominantly present within circumventricular organs, in granular cells of the dentate gyrus and in neurons of the reticular thalamic nucleus. The presence of Shh, Ptc and Smo transcripts in hypothalamic areas may indicate a role of Shh signalling in the modulation of neuroendocrine functions. The expression pattern of these three genes as well as of Gli1, and their developmental regulation in the cerebellum, suggest a possible role for Hedgehog signalling in the control of various cell populations within the cerebellum, particularly in granule cell proliferation and/or differentiation that might be impaired in proliferative states such as medulloblastomas.

"The SU.VI.MAX Study": a primary prevention trial using nutritional doses of antioxidant vitamins and minerals in cardiovascular diseases and cancers. SUpplementation on VItamines et Minéraux AntioXydants

The "SUpplementation en VItamines et Minéraux AntioXydants" (SU.VI.MAX) Study is a randomized double-blind, placebo-controlled, primary-prevention trial which started in 1994 in France. This epidemiologic study is designed to test the efficacy of a daily supplementation with antioxidant vitamins (vitamin C, 120 mg, vitamin E, 30 mg, and beta-carotene, 6 mg) and minerals (selenium, 100 microg, and zinc, 20 mg) at nutritional doses, in reducing the main causes of premature death (cancers and cardiovascular diseases); 12,735 eligible subjects (women aged 35 to 60 years, and men aged 45 to 60 years) were included in 1994 and and will be followed up for 8 years. Participants undergo a yearly visit consisting, every other year, of either biological sampling or clinical examination. They also regularly provide information on health events and dietary intake by filling out computerized questionnaires using the Minitel Telematic Network. After 2 years of supplementation, biochemical indicators of vitamin and trace element status reach reasonable level without reaching concentrations as high as those observed in intervention studies, which tested relatively high doses of antioxidants, and ended up with higher risk of pathology.

Plasma vitamin A, E, and beta-carotene levels in adult post-partum Algerian women

Vitamins A and E are essential for foetal growth, reproduction, and lactation. In this article we report the results of a study, lead in three Eastern Algeria cities, that involved 786 post-partum women and 250 control. Plasma levels of vitamins A, E, beta-carotene, and some nutritional indexes were measured in both groups. In control women, plasma retinol and beta-carotene levels were significantly lower in Algeria than in France (retinol: 1.4 +/- 0.42 vs. 1.78 +/- 0.53 mumol/l; beta-carotene: 0.35 +/- 0.261 vs. 0.94 +/- 0.611). These differences could be the consequence of different beta-carotene and retinol intakes. In Algeria, comparisons between post-partum women and controls, showed that plasma vitamin A and beta-carotene levels were significantly lower in post-partum than in control women. This fact, and the lower level of retinol in control women, raises the question of supplementation for pregnant women in Algeria, at least for those with the lowest standard of living whose protein and zinc levels are also very low after delivery. Plasma vitamin E levels and vitamin E/total lipid ratios were not different in Algeria and in France. Vitamin E concentration was higher during pregnancy, but the vitamin E/total lipid ratio was significantly lower, which shows a relative deficiency at the end of pregnancy. Comparisons of plasma vitamin E levels, at delivery, in primiparous and in multiparous women reveal a better tocopherol status in multiparous women. This difference could reflect an adaptive response to oxidative stress in multiparous women.

Gas chromatographic-mass spectrometric determination of total homocysteine in human plasma by stable isotope dilution: method and clinical applications

The detection and quantitation of slight increases of plasma homocysteine levels is of growing interest. This has prompted us to develop a highly sensitive and accurate capillary gas chromatography-mass spectrometry (GC-MS) method. The method proved to be highly sensitive (DL=0.17 micromol/l) with between- and within-run precision less than 6% and 7%, respectively. Reference values of plasma total homocysteine have been determined for men (n=39) and women (n=36), showing a significant difference (P=0.003) between gender. Preliminary results in cerebrovascular accidents and in venous thrombosis are presented.

[Carotenoids: 2. Diseases and supplementation studies]

Inverse correlations have been found in most studies on the relationship between dietary intake and plasma concentrations of carotenoids on one side and degenerative diseases such as cancer and cardiovascular diseases on the other side. Protective effects of carotenoids have been found for pathologies of the retina and the skin. Concentrations of these molecules in blood are lower in digestive pathologies and HIV. Short- and long-term toxicity of carotenoids was found to be low. In combination with the beneficial effects found for diets rich in carotenoids, this has initiated trials with relatively high doses of carotenoid supplements. In the study in Linxian (China) in a rural population with poor nutritional status, supplementation with beta-carotene, zinc, selenium and vitamin E lowered total mortality and mortality from stomach cancer. Other studies (ATBC, Caret.) on well-fed subjects did not show beneficial effects on mortality from cancer and cardiovascular diseases. On the contrary, higher mortality and lung cancer incidence was found in supplemented subjects that were also exposed to asbestos and cigarette smoke. In these studies, doses of supplemental beta-carotene were high and varied from 20 to 50 mg/day. One still ongoing study, called Suvimax, doses subjects for eight years with a cocktail of vitamins and minerals including 6 mg per day of beta-carotene. This supplementation with physiologically seen more "normal" doses might give clarity on the question if beta-carotene is the protective factor in fruits and vegetables.

Urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine and 5-(hydroxymethyl) uracil in smokers

Cigarette smoke is known to generate free radicals by various mechanisms. In this study involving 30 non-smokers and 30 smokers, we show that urinary excretion of 5-(hydroxymethyl) uracil (HMUra) was not different in the two groups (6.54+/-2.07 vs. 6.70+/-1.68 nmol/mmol creatinine). In contrast, 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dGuo) excretion increased by 16% (1.16+/-0.35 vs. 1.35+/-0.50 nmol/mmol creatinine, p = 0.039). Results concerning 8-oxo-dGuo are in agreement with those of previous studies. We observed significant multiple correlations between HMUra and creatinine (r(p) = 0.44), BMI (r(p) = -0.27) and nicotine derivatives (r(p) = 0.26). Multiple correlation analysis showed relations between 8-oxo-dGuo on the one hand, and: creatinine (r(p) = 0.36), nicotine derivatives (r(p) = 0.29), BMI (r(p) = -0.24) on the other.

[Carotenoids: 1. Metabolism and physiology]

Carotenoids are a family of pigments with at least 600 members. They derive from lycopene after steps of cyclisation, dehydrogenation and oxidation. It is their chemical structure that determines their physiochemical properties and, in part, their biological activities. About 50 carotenoids can be found in human diet and about 20 of them have been found in plasma and tissues. There is no RDA (Recommended Daily Allowance) for carotenoids. Quantities of carotenoids in diet are difficult to estimate, partly because methods used for the establishment of food composition tables were not specific and sensitive enough. Also, given values do not always take into account variations due to season and region of culture. Absorption of beta-carotene in humans has been the subject of numerous studies but only very little is known about other carotenoids. In general, absorption depends on bioavailability from the food matrix and solubility in micelles. After absorption through passive diffusion, carotenoids follow the chylomicrons metabolism. They are taken up by the liver and released in the blood stream in lipoproteins (VLDL). Carotenoids with no-substituted beta-ionone cycles (alpha and beta-carotene and beta-cryptoxanthin) have provitamin A activity. Highest activity has been found for all-trans beta-carotene. Not all steps of vitamin A biosynthesis and metabolism of other carotenoids have been clarified yet. Besides their provitamin A activity, carotenoids have numerous biological functions. They are efficient scavengers of free radicals, particularly of 1O2. In vitro they have been shown to protect LDL. However, results in vivo are inconsistent. Other functions include enhancement of gap junctions, immunomodulation and regulation of enzyme activity involved in carcinogenesis.

Influence of the 'directions for use' on positivity rates of the Hemoccult II test

OBJECTIVE

A concise, detailed, and complete instruction sheet is indispensable for adequate completion by the users of a product. This sheet should be enclosed in the envelope which contains Hemoccult II slides. The authors found that the instructions provided by the French manufacturer were unsatisfactory. They designed a short and simple notice, adequately detailed to be understandable by all volunteers and to obtain satisfactory stool smears. Positivity rates of Hemoccult II performed with the manufacturer's notice were compared to those obtained with Hemoccult II performed with the authors' instructions.

METHODS

This study was made during the third screening campaign carried out by the Office Departemental de Lutte contre le Cancer (ODLC). This screening programme only concerned women 59 to 69 years of age. Six thousand three hundred and ninety-two Hemoccult II containing the manufacturer's instructions were received at the laboratory during March, April, May, June and July 1996, and 2633 Hemoccult II containing the ODLC instructions during March, April, May, June and July 1997. All Hemoccult II were developed and read by one trained technician in the Biochemistry Laboratory (Grenoble University Hospital).

RESULTS

The two populations, studied in 1996 and 1997, were strictly comparable in terms of age and number of previous screenings. Out of 6392 Hemoccult II containing the manufacturer's instructions, 157 (2.5%) were found positive, as compared to 36 (1.4%) Hemoccult II out of 2633 which contained the authors' instructions. This difference is highly significant (P = 0.001).

CONCLUSION

The directions for use provided with Hemoccult II had a crucial influence on positivity rates, and therefore on the cost of screening. The instruction sheet provided by the French manufacturer is not satisfactory as it contains too much needless information, while several important pieces of advice are missing.

Urinary excretion of 5-(hydroxymethyl) uracil in healthy volunteers: effect of active and passive tobacco smoke

The urinary excretion of 5-(hydroxymethyl)uracil (5-HMUra), one of the major oxidative modifications of thymine, was investigated in 134 healthy volunteers living in North Italy. Overnight urine was collected, and a questionnaire was completed on smoking habits and exposure to environmental tobacco smoke (ETS). 5-HMUra was analyzed by GC/MS, following urine purification by HPLC. 5-HMUra excretion showed an approximately normal distribution, ranging from 0.08 to 0.84 (mean 0.44) nmoles/kg/8 hr and from 3.2 to 18.7 (mean 8.5) nmoles/mmoles creatinine. 5-HMUra excretion was significantly higher in women than in men and in smokers than in non-smokers when results were expressed as the ratio to creatinine. Slightly higher levels of 5-HMUra excretion, expressed as nmoles/mmoles creatinine, were also found in subjects highly exposed to ETS, monitored either as the number of hours of exposure or as the number of smokers in the workplace and at home. Our results show that the urinary excretion of 5-HMUra is higher than that of other oxidized nucleobases, including 8-oxo-7,8-dihydroguanine, and can be slightly modified by environmental factors such as tobacco smoke. These findings suggest that measurement of urinary excretion of 5-HMUra could be useful as a biomarker of oxidative DNA damage and repair, though further research is needed to support these data.

Urine 8-oxo-7,8-dihydro-2-deoxyguanosine vs. 5-(hydroxymethyl) uracil as DNA oxidation marker in adriamycin-treated patients

We measured the base 5-(hydroxymethyl) uracil (HMUra) and the nucleoside 8-oxo-7,8-dehydro-2'-deoxyguanosine (8-oxo-dGuo) in urine of adriamycin-treated cancer patients. Adriamycin has been shown to generate oxygen free radicals by various mechanisms. HMUra and 8-oxo-dGuo are two known lesions of DNA, produced by oxygen free reaction on thymine and 2'-deoxyguanosine, respectively. HMUra was measured by GC-MS/isotopic dilution and 8-oxo-dGuo by HPLC/EC, both after prepurification by semipreparative HPLC. Here we report the results of a study involving 20 cancer patients treated with flash doses of ADR. We found that urine HMUra is significantly increased (HMUra (nmol/24h): 80.8 8.44 vs. 98.7+/-6.87; p < 0.01) 24h after administration of the drug, while 8-oxo-dGuo did not show any significant variation. Urine HMUra seems to be a suitable short-term marker of DNA alterations by oxygen free radicals.

Regional distribution of Sonic Hedgehog, patched, and smoothened mRNA in the adult rat brain

In vertebrates, Sonic Hedgehog (Shh), Desert Hedgehog (Dhh), and Indian Hedgehog (Ihh) genes encode a family of morphogen proteins that are implicated in a wide range of signaling activities, particularly during embryonic development. These secreted proteins are proposed to mediate their effects on target cells by interacting with their putative receptor, Patched (Ptc), and with a seven-pass transmembrane protein, Smoothened (Smo). However, the roles that these signaling molecules may play in adult tissues, particularly in brain, are not yet clearly defined. Therefore, we investigated the expression of these genes in adult rat tissues. Northern blot analysis revealed expression of Shh, Dhh, and Ihh genes in peripheral tissues, whereas Shh transcript was also identified in brain. It is interesting that northern blot analysis with probes derived from the mouse Ptc and Smo genes revealed the expression of a 7.9-kb and a 3.7-kb transcript, respectively, in all brain tissues examined. In situ hybridization experiments using specific digoxigenin-labeled riboprobes showed expression of Ptc and Smo transcripts in discrete brain areas. Shh-positive cells were observed in restricted regions of the brain. Within the cerebellum, Shh, Ptc, and Smo transcripts were colocalized in the Purkinje cell layer. These data suggest that, besides its roles in determining cell fate and patterning during embryogenesis, the hedgehog signaling pathway may have also important roles in the adult brain.

[Simultaneous screening of cancers of the breast, cervix, colon and rectum. The Isère experience]

The mass screening program for cancer in the Isere department offers women between 50 and 69 years a medical consultation and three tests: mammography for breast cancer screening, Pap smear for cervical cancer screening, and hemoccult for colorectal cancer. During the first round, 29,570 women took part in the program, 21% had a mammography, 20% Pap smears and 25% a hemoccult. In breast cancer screening, the rate for further examination was 11.9%, the breast cancer detection rate was 5.4 per 1,000 women screened and the detection rate of invasive tumor < or = 10 mm: 2.0 per 1,000. In cervical cancer screening, the rate of abnormal examinations was 1.2%. The cervical cancer detection rate was 1.5 per 1,000. The rate of positive hemoccult was 2.7% and the rate of colorectal cancers and polyps 10 mm or larger was 2.7 per 1000. Results of screening are satisfying, but compliance rate is too low. Acceptance rate must be examined in following rounds.

Rapid high-performance liquid chromatographic assay for salicylic acid in plasma without solvent extraction

The in vivo measurement of highly reactive free radicals, such as the hydroxyl radical (oOH), in humans is very difficult, if not impossible. Specific markers, based on the ability of oOH to attack aromatic molecules and produce hydroxylated compounds, are under investigation. In vivo radical metabolism of salicylic acid produces two main hydroxylated derivatives: 2,3- and 2,5-dihydroxybenzoic acid (DHBA). The measurement of 2,3-DHBA, following oral administration of salicylic acid or its acetylated form (aspirin), is proposed for the assessment of in vivo oxidative stress. The intensity of oxidative stress is a function of the ratio of dihydroxylated derivatives to salicylic acid rather than the absolute dihydroxylated derivatives levels. Consequently, a simple, accurate, and sensitive assay of the salicylic acid level in plasma is needed to investigate the in vivo free radical production. In this work, a rapid and sensitive method is presented that is useful for the quantitation of salicylic acid in biological fluids. The methodology uses high-performance liquid chromatography with spectrophotometric detection for the identification and quantitation of salicylic acid without organic extraction. A detection limit of less than 5 mumol is achieved with spectrophotometric detector responses that are linear over at least 6 orders of magnitude. Plasma concentrations of salicylic acid determined by the present technique are reported following the administration of 1000 mg aspirin in 20 healthy subjects.

5-Hydroxymethyluracil excretion, plasma TBARS and plasma antioxidant vitamins in adriamycin-treated patients

The thymine oxidative lesion-5-hydroxymethyluracil (HMUra)-was measured in urine collected from cancer patients. These patients all received chemotherapy using Adriamycin. Adriamycin (ADR) intercalates DNA coils and interferes with normal cell metabolism through diverse biochemical mechanisms that may explain its different actions. The anticancer action of ADR could derive from its interaction with topoisomerase II, resulting in DNA nicking followed by DNA fragmentation and apoptosis. Side effects of ADR-mainly its cardiotoxicity-may derive from the fact that ADR generates superoxide and hydroxyl radicals in two ways: redox-cycling and a Haber-Weiss type reaction due to Fe-ADR complexes. The oxygen free radicals, particularly .OH, are thought to be produced by ADR directly in genomic material and attack all its components. 5-Hydroxymethyluracil is a thymine lesion provoked by these attacks, and it has been proposed as a marker of DNA alterations. In this article, we report the results of a study involving 14 cancer patients treated with ADR. We found that urine HMUra is significantly increased by the anticancer therapy (HMUra (nmol/24 h): 74.4 9.46 vs. 96.3 8.74; p < .01), this increase reveals a higher risk of mutagenesis. Our study is the first to show an in vivo alteration of DNA by ADR. Results also show that thiobarbituric acid reactants increase significantly, and that the vitamin levels for retinol and alpha-tocopherol, which are antioxidant vitamins, are lower at the end of chemotherapy. We suggest to supplement these patients with vitamins A and E, and selenium to reduce the side effects of ADR.

Zinc changes in blood and urine during cyclic parenteral nutrition: relationships with amino acid metabolism

Serum Zn, ultrafiltrable Zn and amino acids in serum and urine samples of twenty-seven patients receiving cyclic (12 h/24 h) parenteral nutrition were measured. These samples were collected in patients after a 12 h period of parenteral nutrition, and in the evening after 12 h without parenteral nutrition. The same determinations were performed in ten control subjects who followed the same sampling scheme. Total serum ultrafiltrable Zn showed no significant variations in the patients during parenteral nutrition, and was not significantly different in the two groups although the proportion of the Zn present in the ultrafiltrable fraction was elevated. Serum cystine levels were significantly higher (P = 0.05) in the patients than the control subjects, and cystine excretion was also higher in patients (P < 0.05) and increased after parenteral nutrition (56.0 (SE 6.5) v. 147.1 (SE 20.6) mumol/12 h; P < 0.001). Histidine levels did not vary significantly in serum after parenteral nutrition and were not different in the patients in comparison with the control subjects. Histidine excretion was not different in the two groups but increased significantly during parenteral nutrition (P < 0.05). Serum albumin was significantly depressed in the patients compared with the control subjects (45.3 (SE 1.5) v. 33.9 (SE 1.5) g/l; P < 0.001). These results suggest that cystine infusion and excretion relate to the changes occurring in serum Zn and in urinary Zn excretion.