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The cosmic rays propagation inside the heliosphere is well described by a transport equation introduced by Parker in 1965. To solve this equation, several approaches were followed in the past. Recently, a Monte Carlo approach became widely used in force of its advantages with respect to other numerical methods. In this approach the transport equation is associated to a fully equivalent set of stochastic differential equations (SDE). This set is used to describe the stochastic path of quasi‐particle from a source, e.g., the interstellar space, to a specific target, e.g., a detector at Earth. We present a comparison of forward‐in‐time and backward‐in‐time methods to solve the cosmic rays transport equation in the heliosphere. The Parker equation and the related set of SDE in the several formulations are treated in this paper. For the sake of clarity, this work is focused on the one‐dimensional solutions. Results were compared with an alternative numerical solution, namely, Crank‐Nicolson method, specifically developed for the case under study. The methods presented are fully consistent each others for energy greater than 400 MeV. The comparison between stochastic integrations and Crank‐Nicolson allows us to estimate the systematic uncertainties of Monte Carlo methods. The forward‐in‐time stochastic integrations method showed a systematic uncertainty <5%, while backward‐in‐time stochastic integrations method showed a systematic uncertainty <1% in the studied energy range. Quantitative comparison of backward‐forward‐in‐time cosmic rays transport Monte Carlo methodsEstimation of systematic error of both methods for spectra at 1 AU for energies above 1 GVBackward‐in‐time method is suited for predicting modulated spectra for high‐precision experiments

Abstract: The chemical evolution of LiH and LiH+ molecules, possibly formed during the recombination era of the early universe, is usually considered in reactions with H and H+, the latter species being some of the most abundant partners under the above conditions. The quantum method selected in the present work, the negative imaginary potential (NIP) method, is described in great detail and tested in comparison with other methods for various simple reactions. The results show the numerical validity of the NIP approach and confirm our earlier findings on the specific outcomes for lithium reactions of the early universe.

ABSTRACTAdministration of DDC (3,5-diethoxycarbonil-1,4-dihydro-2,4,6-trimethylpyridine) (100 mg/kg, i.p.) to male rats produced significant increase in total porphyrins thus giving rise to the biochemical picture of porphyria(s). Porphyrins, accumulated in hepatic porphyria are putative endogenous ligands for peripheral benzodiazepine receptor. A role of peripheral benzodiazepine receptors in cholesterol transport and metabolism is suggested. Hepatic protoporphyria is associated with hepatomegaly, cholestasis and alterations in the microsomal cytochromes. We found that DDC administration in rat induced lipid disturbances and increased significantly total cholesterol in serum and in liver, as well as total phospholipids in liver. 27-Hydroxycholesterol content was significantly increased in serum and liver by DDC, while phenobarbital had no effect. We assume that the observed lipid disturbances are connected to the accumulation of porphyrins. These effects are probably modulated by porphyrin binding to peripheral benzodiazepine receptors.

Wavelength and mass resolved resonance-enhanced multiphoton ionization (REMPI) excitation spectra of (R)-(+)-1-phenyl-1-propanol (P_R) and its complexes with some chiral diols, i.e. 1,2-propanediols, 2,3-butanediols, and 2,4-pentanediols, have been recorded after a supersonic molecular beam expansion and interpreted in the light of molecular dynamic (MD) conformational minima searches. The spectral features of the selected complexes were found to depend on cooperative hydrogen-bond interactions between the two components, whose intensity depends upon the specific configuration of the diol moiety and the relative position of its hydroxy groups. The study further confirms resonant two-photon ionization spectroscopy, coupled with time-of-flight mass resolution (R2PI-TOF), as an excellent tool for gathering valuable information on the interactive forces in molecular clusters and for enantiodiscrimination of chiral molecules in the gas phase.

Wavelength and mass resolved resonance-enhanced multiphoton ionization REMPI excitation spectra of R--1-phenyl-1-propanol PR and its complexes with some chiral diols, i.e.1,2-propanediols, 2,3-butanediols, and 2,4-pentanediols, have been recorded after a supersonic molecular beam expansion and interpreted in the light of molecular dynamic MD conformational minima searches. The spectral features of the selected complexes were found to depend on cooperative hydrogen-bond interactions between the two components, whose intensity depends upon the specific configuration of the diol moiety and the relative position of its hydroxy groups. The study further confirms resonant two-photon ionization spectroscopy, coupled with time-of-flight mass resolution R2PI-TOF, as an excellent tool for gathering valuable information on the interactive forces in molecular clusters and for enantiodiscrimination of chiral molecules in the gas phase.

The Italian drill “DEEDRI” is going to be the lander based sample acquisition system for the Mars Surveyor Program of the Mars Sample Return mission. DEEDRI is capable to collect core/sand sample of the martian soil down to 50 cm in depth. The MA_MISS experiment belongs to the DEEDRI system and it will be dedicated to observe the wall of the excavated hole in terms of infrared spectral reflectance in the range 0.8–2.8 μm. The spectral sampling is about 20 nm while the spatial sampling is 100 μm over the target. The optical window of MA_MISS is placed very close to the drill tip so that the target view to be observed can span from the soil down to 50 cm. The proximity optics and electronics of MA_MISS have to be very miniaturized since they will be collocated inside the drill tool in a very limited volume of about 25 mm in diameter. On the other side the main electronics will be on the lander and it will communicate through an interface based on slip rings devices. MA_MISS can acquire in different observation modes. The images are scanned by moving the DEEDRI itself. One image ring is built up by acquiring contiguous images of the MA_MISS slit. The study of the Martian subsurface will provide important constraints on the nature, timing and duration of alteration and sedimentation processes on Mars, as well as on the complex interactions between the surface and the atmosphere. This study will permit to infer the history of erosion, transport and deposition of loose material. Alteration processes can dominate the mineralogy of the Martian surface: it will be essential to study the mineralogy of deeper layers, where a more limited alteration took place. MA_MISS can provide very important scientific return from the subsurface of Mars along with a selection criteria for the samples collection.

The haemorheologic condition was evaluated in 43 obese children and 35 controls. In 18 of the obese children and in 21 controls the euglobulin lysis time (ELT) was also studied. Blood viscosity at 94.5 and at 0.204 s-1 shear rates, plasma viscosity, fibrinogen and erythrocyte filtration time were significantly higher in obese than in control children. No significant differences were observed in haematocrit levels. Triglycerides, non-esterified fatty acids (NEFA), pre-ß-lipoprotein and insulin rates were all significantly higher in obese than in control children. There were no significant differences in glycaemia and in haemoglobin A1 values. ELT, both basal and after stimulation with 1-deamino-8-d-arginine-vasopressin (DDAVP), was significantly higher in the obese than in control children. The haemorheologic disturbances together with alterations of the haemostatic balance and fibrinolysis may be an important risk factor for the development of vascular changes at paediatric age.

Rat brain synaptosomes contain an enzyme, phosphatidylethanolamine N-methyltransferase (EC 2.1.1.17), that catalyzes the methylation of phosphatidylethanolamine to form its mono-, di-, and trimethyl (phosphatidylcholine) derivatives. Synaptosomal phosphatidylethanolamine is much richer in polyunsaturated fatty acids (43.4%) than is synaptosomal phosphatidylcholine (4.6%). It thus seemed possible that the phosphatidylcholine derived via the N-methylation of phosphatidylethanolamine might also be especially enriched in polyunsaturated fatty acids. To test this hypothesis, we examined the incorporation of [3H]methyl groups into various molecular species of phosphatidylcholine, by incubating rat synaptosomes for 10, 30, or 90 min in a medium containing S-adenosyl[methyl-3H]methionine. Phosphatidylcholine was extracted and separated from other lipids by TLC, after which its molecular species were isolated by argentation TLC (which distinguishes among the phospholipid molecules by the degree of unsaturation of their fatty acid moieties.) We found that approximately 65% of the [3H]methyl incorporated into phosphatidylcholine during the incubation period was present in the fraction associated with pentaene or hexaene fatty acids; an additional 30% was present in the tetraene fraction, while the remaining phosphatidylcholine radioactivity was distributed between the dienes and monoenes. Similar distributions were observed among synaptosomes incubated for 10 or 30 min; however, after 90 min the phosphatidyl[3H]choline contained proportionately less of the tetraenes. These observations indicate that neuronal phosphatidylcholine molecules formed via N-methylation are especially richer in polyunsaturated fatty acids, and they raise the possibility that these molecules constitute a distinct pool with particular physiologic functions.

Objective: The objective of this study was to evaluate whether a regular formula for premature infants supplemented with nucleotides has any influence on plasma lipids and erythrocyte membrane fatty acids. Methods: Preterm infants fed either human milk supplemented with human milk protein (HM, n= 14), nucleotide‐supplemented preterm formula (NF, n= 13), or a regular preterm formula (F, n= 13) were included in the study. The NF was supplemented with 18.2 mg cytidine monophosphate/1 (CMP), 7.0 mg uridine monophosphate/1 (UMP), 6.4mg adenosine monophosphate/1 (AMP), 3.0mg inosine monophosphate/1 (IMP) and 3.0 mg guanosine monophosphate/1 (GMP). Results: There were significantly higher concentrations of triglycerides (TG) in infants fed NF compared to those fed F (191.42 ± 79.58 vs 108.21 ± 43.73, p< 0.001, mean ± SD lipid concentrations, mg/100ml plasma). Infants fed F had significantly lower concentrations of total cholesterol (94.34 ± 11.71 vs 115.69 ± 39.29, p< 0.01) and TG in plasma (108.21 ± 43.73 vs 172.27 ± 68.19, p< 0.001, mean ± SD lipid concentrations, mg/100ml plasma) when compared to HM‐fed infants. There were no significant differences in any of the erythrocyte membrane fatty acids and total long‐chain polyunsaturated fatty acids (LC‐PUFA) between NF and F during the study period (6 weeks). Furthermore, total LC‐PUFA and docosahexaenoic acid (DHA) concentrations in red blood cell were not significantly different when infants fed NF were compared to those fed HM. In contrast, however, infants fed F had significantly lower concentrations of total n‐3 LC‐PUFA (p< 0.01) and DHA (p< 0.01) than those found in HM‐fed infants. Conclusions: These results do not suggest an effect of nucleotides on the red blood cell LC‐PUFA profile in preterm infants. However, the nucleotides may increase the concentrations of triglycerides in plasma.

The effects of L-carnitine (LCn) and acetyl-L-carnitine (AcLCn) were assessed on the liver alterations observed in Kilpatrick's model of Reye syndrome in rats; fasted rats were given lipopolysaccharide (LPS), 0.2 mg/kg i.p., 12 hr before they were sacrificed, plus acetylsalicylic acid (ASA), 50 mg/kg i.p., 11 hr before sacrifice; LCn or AcLCn were given twice, 500 mg/kg orally, 12 and 2 hr before sacrifice. LPS+ASA-treated rats showed a dramatic decrease of hepatic ketone bodies and acetyl-CoA and an increase of isobutyryl-CoA, isovaleryl-CoA and succinyl-CoA. Electron microscopy of LPS+ASA-treated rat liver showed a slight but significant alteration in mitochondrial inner structure. Because impairment of mitochondrial function in RS is associated with swelling, we investigated whether the microviscosity of mitochondrial lipids and the cholesterol-phospholipid ratio (CHOL/PL), were involved in the RS model used. Mitochondria from LPS+ASA-treated rats showed a decrease in lipid microviscosity, in CHOL/PL ratio and in CHOL/PL ratio of both inner and outer membrane fractions; these alterations suggested a general increase in membrane fluidity. LCn and AcLCn reversed the morphological alterations in mitochondria after LPS+ASA, observed by electron microscopy, the decrease in KB and the toxic increase in short-chain acyl-CoAs; AcLCn only reversed the decrease in acetyl-CoA. LCn and AcLCn prevented mitochondrial lipid alterations mainly in the inner membrane fraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Nine cases of adrenocortical tumor are presented, six were males. Four were less than three years and five were between 5 and 10 years of age. Clinical virilization was found in 8 children, one had only signs of hypercortisolism and another showed signs of virilization and hypercortisolism simultaneously. Urinary 17-KS and 17-OHCS were high in all patients. Plasma levels of testosterone and of the other adrenal androgens were high in all the cases tested. Plasma level of cortisol was elevated only in few cases. In two out of five cases steroids were only partially suppressed by dexamethasone. Computed tomography and abdominal sonography have been useful tods for the localization of the tumour. The resection of the tumour, indipendent of hystopathological diagnosis, led to a complete normalization of the clinical and hormonal picture in eight cases evaluated at a distance of 2 months 10 years after surgery. In one case a hepatic metastasis was observed and removed three years after surgery.Adrenocortical tumours are rare (Javadpour et al., 1980) and the vast majority of them are hormone secreting. Although cases have been described which showed feminilization and hyperaldosteronism (Bacon & Lowrey, 1965; Bhettay & Bormici, 1977; Crane et al., 1961; Gauguly et al., 1980), virilization and hypercortisolism are most commonly found (Hayles et al., 1966).This paper illustrates our experience with nine cases of adrenocortical tumour, eight of whom showed inappropriate virilization with or without hypercortisolism and one of whom was a classic case of Cushing's syndrome.

We studied three groups of patient with coeliac disease: group 1=95 adult patients with gastro-intestinal symptoms diagnosed after reaching adult height, 41 of whom had had symptoms during childhood; group 2=23 adult patients with classic coeliac disease treated before or during puberty; group 3=11 coeliac children with short stature and no gastro-intestinal symptoms diagnosed and treated before or during puberty. We evaluated the adult height in groups 1 and 2 and the growth during the first years of diet in group 3. Our study leads us to the following conclusions. Dieting leads to a modest increase (on average not more than 3 cm) of the final height of coeliac patients. Subjects with gastro-intestinal symptoms who have been treated before adulthood reach a mean height similar to the normal population and have a slightly better adult height than non-treated subjects. This difference seems to exist only in men and this might be related to puberty evolving more rapidly in women receiving treatment. Subjects without symptoms during childhood reach a normal final height even without treatment. In our patients, early treatment seemed to have no great effect on adult height.

The usefulness of serum DU-PAN-2 in diagnosing pancreatic cancer and in distinguishing between this cancer and other benign and malignant diseases, and to assess the role of liver dysfunction in altering the serum levels of this marker were investigated. DU-PAN-2 was measured in the sera of 31 patients with pancreatic cancer, 32 with chronic pancreatitis, 20 with benign and 21 with malignant extra-pancreatic diseases. DU-PAN-2 was found to be above 300 U ml-1 in 21/31 patients with pancreatic cancer (sensitivity 68%). Only 3/32 patients with chronic pancreatitis had abnormal values. A substantial number of patients with both benign and malignant extra-pancreatic diseases had an elevated serum DU-PAN-2 (9/20 and 15/21, respectively). Correlations were found between DU-PAN-2 and (1) total bilirubin, (2) alanine-amino-transferase and (3) alkaline phosphatase. Of the patients with high DU-PAN-2 values, jaundice was found in: 2/3 with chronic pancreatitis, 9/10 with benign and 12/14 with malignant extra-pancreatic diseases. In conclusion, the serum DU-PAN-2 test for pancreatic malignancy is not completely satisfactory, because it is not sensitive enough. While the test for chronic pancreatitis has an acceptable specificity, the assay cannot distinguish between pancreatic cancer and other extra-pancreatic diseases, mainly of the liver and biliary tract. Liver dysfunction as well as jaundice seem to considerable affect the levels of this marker, as reported elsewhere for CA 19-9.

Summary One of the earliest biochemical effects induced by the herbicide paraquat (PQ) is damage to type II pneumocytes with consequent depletion of surfactant (Skillrud and Martin, 1984). We made a series of studies on the possible protective effect of drug ambroxol, which induces surfactant synthesis from alveolar type II cells (Post et al. 1983). The cell line A-549, exposedin vitro to PQ concentrations ranging from 0.5×10-4 to 2×10-3 M, showed a significant dose-dependent loss of viability. Ambroxol (10 mg/ml) pretreated cells were more resistant to PQ, their viability starting to decrease from a PQ concentration of 0.8×10-3 M. Membrane microviscosity was measured on the same cells. Cells treated with PQ alone showed a reduction of membrane microviscosity which was significantly counteracted by ambroxol pretreatment. The curves for membrane microviscosity of PQ and ambroxol-plus-PQ-treated cells overlapped those for cell viability, indicating that the stimulation of surfactant synthesisin vitro may be a prerequisite for counteracting some of the precocious effects of PQ. Partial protection from PQ- induced mortality was also obtainedin vivo.

A NUMBER of experimental conditions, including various types of stress1and several treatments including administration of adrenocorticotrophic hormone (ACTH)2, ethanol3, carbon tetrachloride4and ethionine5induce an increase of the level of liver triglycerides.

Aims.We reassess the role of HeH+with the aid of newly calculated rates that use entirely ab initio methods, which thereby allow us to compute with higher accuracy the relevant abundances within the global chemical network of the early universe. A comparison with the similar role of the ionic molecule LiH+is also presented.

Sm-C increase during puberty or sex hormones treatment. Whether this increase is mediated by GH is still unclear. Children with testicular feminization submitted to gonadectomy provide a good model to assess the role of sex steroids on GH secretion. we evaluated Sm-C, T and E2 in 9 testicular feminized girls (mean age 11.6±1 yrs) immediately before and after gonadectomy. In 3 subjects GH release was evaluated by means of a sleep test. Hean Sm-C before surgery (2.85 UI ± 1.23) was significantly higher than that after gonadectomy (1.39±0.9, p<0.025) and than that of normal controls (n 83) (1.68±1.04, p<0.025). In all 3 patients the sleep test showed GH values higher before surgery by 1 SD over the mean value of control subjects and a GH decrease after gonadectomy (see table).Though the number of subjects studied is small, the fact that all showed the same Gil behaviour allows us to hypothesize that the higher Sm-C values before surgery, in spite of androgen insensitivity, are the expression of the high testosterone (or estradiol) levels oF these subjects and the Sm-C increase seems mediated through enhanced GH secretion.

It is generally agreed that chronic diarrhea due to CMA resolves with a cow's milk (CM)-free diet, and that tolerance to CM is achieved by two years of age. We have followed-up to 4-10 years 41 infants with chronic diarrhea due to CMA, who had at onset of diarrhea RAST and/or skin tests positive to CM. The infants were given a lamb diet prepared as follows (per liter): meat 100g, rice flour 70 g, olive oil 40 g, table salt 2 g. After the diarrhea subsided, the CM-reintroduction was attempted at 6-month intervals. In 25/37 (67.5%) children (4 cases were lost in the follow-ups) CMA resolved at a median age of two years, whereas 12/37 (32.5%) children do not yet tolerate CM at a median age of 6 years. In addition, a large proportion of children (27/37=73%) suffered during the follow-up period from other atopic symptoms, due either to CMA or to inhalant allergy. However, females appear to be either more prone to develop tolerance to CM, or less affected by other atopic diseases. 15/17 males and 12/20 females developed other atopic diseases. Our data suggest that in infants with chronic diarrhea due to CMA, RAST and/or skin tests positive to CM may indicate either the tendency of CMA to persist throughout childhood, or the risk of developing other atopic disorders.