[The rational basis for the short-, medium-, and long-term evolution of the pharmaceutical industry]

In the last few years, a worldwide reorganization affecting the entire pharmaceutical industry has begun and is now accelerating. This intense trend of mergers, acquisitions, market entires++ and exits, reorientation and diversification reflects a new environment. This article sets out to explain the reasons behind this inescapable and rapid evolution.

[Strategic analysis and the drug industry]

During the postwar decades, the quasi-spontaneous growth permitted less rigorous management than that of today in terms of the development of enterprises. The choice was made in a more or less well-considered way and often by 'feeling'. The economic upheaval that followed the oil crises, the acceleration of technological discoveries and their practical applications and the speeding up of the dissemination of information have imposed a new way of strategic decision making on society. This type of approach, used largely in the industrial world, ought to be better understood by doctors so that they may appreciate the changes and also so that they can eventually use these methodologies in their field of activity.

Antioxidant micronutrients and childhood malignancy during oncological treatment

Serum antioxidant vitamins A (retinol) and E (alpha-tocopherol), beta-carotene, zinc, and selenium, and cholesterol and related proteins for 170 children with newly diagnosed malignancy were measured at diagnosis and 6 months after initiation of treatment, and compared with those of 632 cancer-free controls. Incident cancer cases and controls were 1-16 years old and recruited between 1986 and 1989. At diagnosis, age- and sex-adjusted serum concentrations of retinol, beta-carotene, zinc, and alpha-tocopherol were significantly inversely associated with cancer. No significant decreases in mean values were observed at 6 month, except for the alpha-tocopherol-to-cholesterol ratio in patients with bone tumors and serum zinc in bone tumors and central nervous system malignancies. An increase during the period of treatment was found for retinol and selenium in leukemia patients. beta-carotene was maintained at the initial concentrations determined prior to therapy. These findings provide further information about micronutrient requirements in children with cancer.

Assessment of serum antioxidant micronutrients and biochemical indicators of nutritional status in children with cancer in search of prognostic factors

Serum vitamins A (retinol) and E (alpha-tocopherol), beta-carotene, zinc and selenium, and related proteins for 157 children with newly diagnosed and histologically proven malignancy were compared with those of 632 cancer-free controls. Incident cancer cases and controls were 1-16 years of age and recruited in 1986-1989. Age and sex-adjusted serum concentrations of beta-carotene and alpha-tocopherol were significantly inversely associated with cancer. No significant association with cancer was observed for serum values of selenium. Although low levels of antioxidants might in part be involved through a causality link, the reported decreased peripheral nutrient levels are considered rather as an impairment of the body's defence system, occurring during the cancer-related metabolic and nutritional disturbances and inflammation processes. The cancer cases group was followed-up and examined 6 months after diagnosis. Among the 157 subjects, 24 had died and 133 were reported to be alive. No substantial difference for any antioxidant or chemistry variable at onset was observed as a function of clinical outcome and health status.

[Opposable medical references in pediatrics]

Recommended guidelines for medical practice are instituted in France as a contribution to a reduction of health care expenses. The methodology, applications, and implications in pediatrics, are presented.

[Efficacy of oral administration of a micellaar solution of vitamin K during the neonatal period]

BACKGROUND

Oral administration of vitamin K to neonates is quite satisfactory for preventing hemorrhagic disease of the newborn. The aim of this study is to test efficacy of a micellar solution of vitamin K at birth.

POPULATION AND METHODS

Thirty full term infants, exclusively breast-fed during the first month of life, were included in this study. Seven of them (control group Cos) were given oral supplementation with 5 mg vitamin K1, cremophor; 15 other infants were given oral supplementation with 3 mg micellar solution of vitamin K1 (group MMos) and 7 were given an intramuscular injection of 1.5 mg micellar solution of vitamin K1 (group MMim). Prothrombin time activity and plasma vitamin K concentration were measured in the cord blood, 24 +/- 12 hours and 1 month after supplementation.

RESULTS

No hemorrhage was seen and tolerance to vitamin K was good in the 3 groups. Mean prothrombin time activity was 54% in the cord blood, around 55% and 75%, 24 hrs and 1 month after supplementation, respectively; only one infant had low value (41%) by 1 month despite normal plasma vitamin K concentration. Two infants had low plasma vitamin K1 concentration by the second control despite normal prothrombin time activity; one belonged to the MMos group and the other to the Cos group. Mean values of plasma vitamin K1 concentration were higher by 1 month in the MMos group.

CONCLUSION

A unique dose of micellar solution of vitamin K given orally at birth seems effective to prevent hemorrhagic disease.

A randomised controlled trial to test equivalence between retinyl palmitate and beta carotene for vitamin A deficiency

OBJECTIVES

To determine whether beta carotene is therapeutically equivalent to retinyl palmitate in the formulation currently recommended by the World Health Organisation.

DESIGN

Randomised blind equivalence trial.

SETTING

Rural area in Senegal.

SUBJECTS

Children aged 2-15 years suffering from vitamin A deficiency as defined by abnormal results on eye cytology were randomly allocated treatment with retinyl palmitate (n = 256) and beta carotene (n = 254).

MAIN OUTCOME MEASURE

Reversion to normal results on eye cytology as defined by the reappearance of goblet cells and normalisation of the epithelial cells.

RESULTS

Seven weeks after the supplement was given the percentages were 51.2% (124/242) children taking retinyl palmitate and 50.0% (123/246) of those taking beta carotene, who had reverted to normal eye cytology, a difference of 1.2% (95% confidence interval 6.2% to 8.6%) [corrected]. According to an equivalence testing procedure, the two treatments were statistically equivalent; the null hypothesis of non-equivalence was rejected (one tailed p value = 0.03).

CONCLUSIONS

beta Carotene supplementation seems to be a promising candidate for the alleviation of vitamin A deficiency. It could be given either as high dose capsule or through increased dietary intake. The challenge now is to improve dietary intake of vitamin A in programmes that are effective and sustainable at the community level.

Serum beta-carotene and antioxidant micronutrients in children with cancer. The 'Cancer in Children and Antioxidant Micronutrients' French Study Group

Serum antioxidant vitamins A (retinol) and E (alpha-tocopherol), beta-carotene, zinc and selenium for 418 children with newly diagnosed malignancy were compared with those of 632 cancer-free controls. Incident cancer cases and controls were 1-16 years old and recruited in 1986-1989. Age- and sex-adjusted serum concentrations of retinol, beta-carotene and alpha-tocopherol were significantly inversely associated with cancer. In similar models, the odds ratio (OR) comparing the highest with the lowest quintile was 2.06 (95% confidence interval [CI] 1.40-3.02) for retinol, 3.87 (95% CI: 2.54-5.90) for beta-carotene, 2.15 (95% CI: 1.48-3.10) for alpha-tocopherol, 1.29 (95% CI: 0.75-2.23) for selenium, and 1.94 (95% CI: 1.17-2.23) for zinc. The cancer sites that were associated with serum beta-carotene were, in general, leukaemia, lymphoma, central nervous system, bone and renal tumours. Moreover, leukaemia was associated with low mean serum levels of retinol, selenium and zinc. Subjects with lymphoma, bone and renal tumours also had lower mean retinol and alpha-tocopherol levels than controls. Brain tumour patients had low vitamin E levels. Low serum values of antioxidant vitamins were associated with childhood neoplasm occurrence. Some site-specific effect was reported. Low peripheral nutrient levels are not considered as cancer promoters but rather as an impairment of the body's defence mechanism occurring during the cancer-related metabolic and nutritional disturbances and inflammation processes.

Reference values for serum zinc and selenium of French healthy children

Age - and sex-specific reference intervals derived from a healthy pediatric population are presented for zinc, selenium and related analytes in serum. No strong correlations were found between age, sex and trace elements in serum. Serum variables were discussed to assess their ability as biochemical indicators of micronutrient status in the field of biological epidemiology.

Immunonephelometry and radial immunodiffusion compared for measuring serum retinol-binding protein

We compared a nephelometric method and a radial immunodiffusion (RID) assay for the measurement of retinol-binding protein in samples of serum from children with malignancies. The mean (+/- standard deviation) retinol-binding protein concentration as measured by the Behring Nephelometer was 31.0 +/- 15.6 mg/l; the mean by RID was 31.2 +/- 15.7 mg/l. This difference was not statistically significant by Student's t test (P = 0.6), and the correlation coefficient (r) was 0.87. Thus, the Behring Nephelometer method measures retinol-binding protein rapidly and as accurately as radial immunodiffusion.

Efficacy of massive oral doses of retinyl palmitate and mango (Mangifera indica L.) consumption to correct an existing vitamin A deficiency in Senegalese children

Administration of large oral doses of retinyl palmitate has become the most widely practised vitamin A deficiency prevention strategy in developing countries. We conducted a follow-up study among 220 Senegalese children aged 2-7 years suffering from moderate undernutrition to determine the efficacy of vitamin A treatment on their vitamin A status assessed by biochemical and cytological (impression cytology with transfer) methods. The first examination (T = 0 m[onth]) was carried out during April 1989, before the mango (Mangifera indica L,) harvest. The second examination (T = 2 m) was carried out 2 months after vitamin A treatment during June 1989 when ripe mangoes become widely available. Conjunctival cells of the eyes of the children with or without ocular inflammation were responsive to vitamin A administration (P < 0.01). There was a significant increase (P < 0.001) in mean serum retinol and beta-carotene levels between T = 0 m and T = 2 m. Mean serum retinol-binding protein (RBP) and transthyretin (TTR) levels did not differ significantly (P > 0.05) at T = 0 m and T = 2 m. Despite the intake of vitamin A, 54% of the children who had abnormal cytology at T = 0 m remained abnormal at T = 2 m. This was due to inadequate levels of TTR and RBP, presumably due to the cereal diet eaten by the Senegalese population. children with abnormal eye cytology had lower serum retinol levels than those with normal eyes at T = 0 m, and beta-carotene values did not correlate with eye cytological abnormalities at T = 0 m. Children with normal cytology had higher serum retinol and also beta-carotene levels than those with abnormal cytology after massive oral doses of vitamin A and consumption of mangoes at T = 2 m. Retinyl palmitate may, therefore, only lead to partial cytological improvement due to a lack of retinol-carrier proteins but dietary beta-carotene may also be involved.

Conjunctival impression cytology with transfer as a field-applicable indicator of vitamin A status for mass screening

The increasing importance of vitamin A deficiency in even its mild subclinical form underlines the need for a mass screening test. Clinical, biochemical and cytological methods of assessing vitamin A deficiency in a public health setting have been described and widely used. The cytological method shows promise because it enables early detection of vitamin A deficiency. However interpretation is problematic since histopathological changes are gradual with the progressive disappearance of goblet cells and appearance of enlarged epithelial cells. The reliability and validity of the impression cytology with transfer (ICT) test were assessed in order to produce a meaningful standard for this cytological method. The ICT test was performed in Senegal on 1451 children, in the course of two surveys conducted in 1989 and 1990 in rural areas. Reliability, estimated by Cohen's kappa test for evaluating intra-reader variability, and sensitivity were highest for the abnormal-normal classification (kappa = 0.91; 95% confidence interval (CI): 0.89-0.93; and sensitivity = 74%; 95% CI 66-82%). The ICT method is a cheap, noninvasive and easy test to perform in the field. This method is also reproducible and fairly sensitive according to the abnormal-normal classification. As illustrated by our proposed 50% cutoff of abnormal cytology calculated in relation to 5% of serum retinol values below 0.35 mumol/L criterion, ICT only requires a small sample for the assessment of the overall health of a community in contrast to xerophthalmia and blood vitamin A deficiency tests.

Laser Immunonephelometry Reference Intervals for Eight Serum Proteins in Healthy Children

Eight serum proteins were analyzed with the Behring nephelometer in samples from 479 healthy French children, ages three to 16 years. Girls had higher concentrations of IgM and albumin than boys had. Age appeared to be a main factor of variation for the proteins tested. Reference intervals are presented for IgG, IgA, IgM, albumin, transthyretin (prealbumin), retinol-binding protein, alpha 1-acid glycoprotein, and C-reactive protein. The significance of increased concentrations of C-reactive protein within a community is discussed.

Retinyl palmitate hydrolase activity in human liver

Retinyl palmitate hydrolase (RPH) activity was studied in human liver after the optimal conditions of the assay in normal human liver homogenates were determined. The mean activity was 118 +/- 66 nmol.min-1.g-1 (mean +/- SD) protein in liver homogenates from six children and seven adults; no correlation was found between liver hydrolase activity and the enzyme endogenous substrate, ie, liver vitamin A concentrations. RPH activity was also studied in a human model of vitamin A deficiency represented by 22 children with biliary atresia: 11 patients with vitamin A deficiency (liver vitamin A concentration less than 70 nmol/g wet wt of liver) and 11 patients with normal vitamin A status after vitamin A treatment. The enzymatic assay had to be conducted after the removal of endogenous bile salts by cholestyramine because bile salts are accumulated in the liver of children with biliary atresia. No correlation was found between RPH activity and vitamin A status.

Laser immunonephelometry reference intervals for eight serum proteins in healthy children

Eight serum proteins were analyzed with the Behring nephelometer in samples from 479 healthy French children, ages three to 16 years. Girls had higher concentrations of IgM and albumin than boys had. Age appeared to be a main factor of variation for the proteins tested. Reference intervals are presented for IgG, IgA, IgM, albumin, transthyretin (prealbumin), retinol-binding protein, alpha 1-acid glycoprotein, and C-reactive protein. The significance of increased concentrations of C-reactive protein within a community is discussed.

Pharmacokinetics and safety of a new solution of vitamin K1(20) in children with cholestasis

In cholestatic diseases, the absorption of fat-soluble compounds, including vitamin K1(20), is low and periodic administration of vitamin K1(20) is often necessary. Due to the low absorption of vitamin K1(20) from the Konakion formulation, late hemorrhagic disease of the newborn also occurs especially after oral vitamin K1(20) prophylaxis with Konakion. We investigated the pharmacokinetics and the safety of a new formulation of vitamin K1(20) in a mixed micelles (MM) solution. Compared to the old formulation (Konakion) using Cremophor EL as a solubilizer, the higher vitamin K1(20) levels (as measured by HPLC) in serum obtained after oral administration of the MM formulation clearly demonstrate a superiority of this new formulation. Additionally, the elimination of Cremophor EL as well as of propylene glycol from the formulation avoids possible adverse effects associated with intravenous or intramuscular administration. Furthermore, in most cases, the discomfort of parenteral injections can be overcome by simple oral administration even in children with severe cholestasis.

Assessment of vitamin A deficiency in the Republic of Djibouti

In a countrywide survey, we assessed the prevalence of vitamin A deficiency by clinical examination and impression cytology with transfer method (ICT) in a randomized sample of 2445 subjects representative of the population of the Republic of Djibouti. A plasma retinol determination was made on a part of this sample. Results lead to believe that serious vitamin A deficiency may periodically occur in Republic of Djibouti when nutritional conditions become poor. Meanwhile a large number of children, mostly in the rural area, have a marginal vitamin A status and are exposed to a high level of risk.

Prevalence of malnutrition and vitamin A deficiency in the Diourbel, Fatick, and Kaolack regions of Senegal: a controlled study

Two hundred and six Senegalese preschool children included in an epidemiological study were selected by their results from impression cytology with transfer (ICT) for assessment of their nutritional state by means of biological variables and for assessment of the diagnostic values of the ICT. A problem of protein-calorie malnutrition existed (transthyretin and retinol-binding protein concentrations were low) associated with vitamin A deficiency (retinol concentrations were low). The sensitivity and specificity of the ICT defined with respect to retinol (threshold fixed at 0.35 mumol/L) varied with the classification criteria of ICT and seemed to be fairly insensitive but specific.

Prevalence of malnutrition and vitamin A deficiency in the Diourbel, Fatick, and Kaolack regions of Senegal: epidemiological study

The purpose of our study was to determine the prevalence of protein-calorie malnutrition (PCM), ocular diseases, and vitamin A deficiency in preschool children selected at random in a rural zone of the groundnut belt of Senegal. The prevalence of PCM was 37.1% (95% CI 33.8-40.2%) according to the Waterlow classification, with a majority of stunting, and prevalence of hypovitaminosis A was estimated to be 11.4% (95% CI 9.3-13.5%) by using impression cytology. Furthermore, 19.4% (95% CI 15.8-22.0%) of the children might be defined at risk of deficiency. The prevalence of Bitot's spots was equal to 0.2% (95% CI 0.03-0.9%). A problem of PCM associated with a health-endangering vitamin A deficiency existed.

Prevalence of malnutrition and vitamin A deficiency in the Diourbel, Fatick, and Kaolack regions of Senegal: feasibility of the method of impression cytology with transfer

The evaluation of the prevalence of ophthalmological diseases and vitamin A deficiency in Senegalese preschool-aged children enabled us to confirm the method of impression cytology with transfer (ICT) and to assess the impact of ophthalmological diseases on the cytological appearance of conjunctival cells. A simplification of the ICT method consisted of transferring cells present on a strip of paper to a glass slide by finger pressure. Harris-Schorr staining of the sample papers confirmed the results obtained by the transfer. Inflammatory trachoma influenced the results of the test. This simple method will prove very helpful for detection of vitamin A deficiency in children in underdeveloped areas.

Regulation of metabolism of retinol-binding protein by vitamin A status in children with biliary atresia

Regulation of retinol-binding protein (RBP) by vitamin A status was studied in 43 children; 25 had biliary atresia and vitamin A deficiency, 15 had biliary atresia treated by vitamin A, and 9 control children had normal liver and vitamin A status. Vitamin A and RBP were assayed and the two forms of RBP, holo-RBP and apo-RBP, were separated in both liver and plasma. No difference in liver RBP concentrations was found between the three groups; apo-RBP was the most abundant form. Plasma RBP concentrations and the ratio of retinol to RBP were lower for vitamin A-deficient than for vitamin A-treated children. Two models could be proposed: 1) a preferential secretion of holo-RBP with variations in RBP catabolism or synthesis in vitamin A-deficient liver and 2) a continuous secretion of RBP by the liver with a rapid clearance of plasma apo-RBP in vitamin A deficiency.

Eicosanoid synthesis in children with cholestatic disease

The possibility of malabsorption of triglycerides contained in the diets of children with cholestasis suggests a deficiency of essential fatty acids and, therefore, probable effects on eicosanoid metabolism. Children with either biliary atresia (BA) or syndromatic paucity of interlobular bile ducts (PILBD) were evaluated as to plasma and platelet total lipid fatty acid composition and synthesis of prostaglandins (PG) E1, PGE2, PGI2, PGF2, and thromboxane (TXB2) by whole blood incubated at 37 degrees C for 10 min. In both diseases linoleate deficiency was present as shown by low 18:2 fatty acids in plasma lipids. The children with BA had lower plasma arachidonate than controls but normal eicosanoid synthesis except for excess PGI2. Those with PILBD had low platelet arachidonate and were severely deficient in TXB2 synthesis (less than 10% of controls). Three children with PILBD were fed a supplement of structured triglyceride (Captex 810) intended to provide as much as 10% of energy as linoleate for 2-3 months. Results for these three cases suggested that insufficient linoleate was absorbed to increase plasma linoleate and differences in eicosanoids could not be attributed to linoleate supplementation.

Short- and long-term vitamin A treatment in children with cholestasis

Newborns have limited reserve supplies of vitamin A. Infants with chronic cholestasis are in a precarious nutritional state because of their limited ability to build these stores even though the vitamin is present in their diet. In this study, we investigated liver concentrations of vitamin A in 30 children with extrahepatic biliary atresia. We demonstrate that correction of the deficiency occurs after intramuscular administration of a water-miscible solution of retinyl palmitate (100,000 IU, or 30 mg retinol equivalent). Furthermore, we evaluated the effect of vitamin A injections on liver and blood concentrations in nine children with chronic cholestasis over a 1-y period. We conclude this treatment is efficient and is well tolerated.

[Hepatitis probably caused by Plethoryl. Apropos of 7 cases]

Seven patients developed acute hepatitis after receiving Plethoryl for obesity for 4 to 16 weeks. Jaundice was generally associated with or preceded by asthenia, nausea and pruritus. Serum aminotransferase activities were markedly increased whereas alkaline phosphatase and gamma-glutamyltransferase activities were moderately elevated. There was no hepatic failure. In all cases, Plethoryl administration was promptly discontinued. In 6 cases, jaundice disappeared within 2 to 4 weeks, and recovery occurred within 2 to 5 months. In one case, however, jaundice disappeared within 12 weeks and recovery took 10 months.

[Vitamin A: an indirect factor in the prevention of cancer]

Although vitamin A intervenes essentially in the mechanism of sight, its possible role in the prevention and treatment of cancer is widely discussed. Epidemiological studies have demonstrated a correlation between vitamin A deficiency and an increase in the frequency of cancers in man. Several hypotheses have been put forward concerning the mechanism of interaction between vitamin A and cancer on the basis of experimental models showing that vitamin A exerts a protective action against spontaneous or induced neoplasias in animals. The toxicological aspects of vitamin A administration and the relevance of these experimental results to human oncology are discussed.

Liver levels of vitamin A and cellular retinol-binding protein for patients with biliary atresia

We have examined whether the amount of cellular retinol-binding protein in human liver is related to the amount of vitamin A stored in the liver. Levels of vitamin A, as retinol and retinol esters, and of cellular retinol-binding protein have been determined in liver samples from 6 normal adults and 11 children with biliary atresia, with and without vitamin A treatment. The level of cellular retinol-binding protein in the liver was not related to the liver vitamin A concentration examined over a 300-fold range of vitamin A levels. Also, biliary atresia did not appear to interfere with storage of vitamin A, and the level of cellular retinol-binding protein was comparable to that observed in the liver of normal adults. The demonstration of proper vitamin A storage in treated children as well as normal levels of cellular retinol-binding protein suggest the vitamin A deficiency frequently observed in children with biliary atresia may be due primarily to faulty absorption rather than a combination of poor absorption and impaired hepatic vitamin A metabolism.

[Percutaneous extraction of pigment lithiasis of the choledochus in an infant]

The authors present the first report of a pigment gallstone of the common bile duct in a 2 month-old infant treated in a non-surgical manner. The gallstone extraction was percutaneous, by a small catheter introduced in the biliary tract under ultrasound control. The clinical and ultrasonographic follow-up (19 months) confirmed complete recovery. This new therapeutic modality might avoid surgery for primary common bile duct cholelithiasis.

Biochemical indicators of vitamin A depletion in children with cholestasis

Biochemical indicators of vitamin A status were measured in 24 children (1 month to 6 years old) with severe cholestasis starting early in life and in 21 children (3 months to 13 years old) with liver disease but without cholestasis. Liver vitamin A concentrations, expressed as micrograms of retinol per gram of liver (mean +/- S.D.), were 6.3 +/- 7.1 (range: 0.14 to 28) and 143 +/- 108 (range: 18 to 424), respectively, in cholestatic and non-cholestatic children. In infants less than 6 months of age, liver vitamin A values less than 10 micrograms per gm were found in 14 of 17 cholestatic children but in none of 3 non-cholestatic subjects. Plasma vitamin A values, expressed as micrograms of retinol per deciliter (mean +/- S.D.), were 23 +/- 18 (range: 3 to 62) and 46 +/- 33 (range: 14 to 125), respectively, for the two groups. Plasma retinol values less than 10 micrograms per dl were always associated with liver concentrations less than 10 micrograms per gm. Plasma retinol-binding protein was only reduced to 71% of control values in cholestatic children. The fatty acid composition of liver retinyl esters was unaffected by any condition studied. Infants with chronic cholestasis are in a precarious nutritional status very early in life relative to liver reserves of vitamin A. Plasma vitamin A values, unless less than 10 micrograms retinol per dl, are poor indicators of inadequate vitamin A status.

Maple syrup urine disease: two different forms within a single family

A family is reported in which the index case presented with an acute form of maple syrup urine disease (MSUD), whereas two of her sisters and her father were found to have an almost asymptomatic form of the disease. It is proposed that the members of this family are compound heterozygotes for the classical deficient mutant gene and for a "variant" allele.

[Vitamin A status in liver diseases in children. Study based on 79 hepatic biopsies]

The authors studied the vitamin A status of 79 children, 71 of whom had liver disease. Plasma levels indicate low vitamin A concentration only when they are below 10 micrograms/dl. Study of liver concentration is currently the reference to appreciate vitamin A status. These concentrations are low in children with cholestasis. The lower the liver concentration, the higher the percentage of retinol in the liver. The percentage of the various retinyl esters is however independent of liver concentrations. The authors propose a model for the regulation of vitamin A metabolism within 4 pools.

Gradient reversed-phase high-performance liquid chromatographic separation of naturally occurring retinoids

A gradient reversed-phase high-performance liquid chromatographic technique is described for the facile separation and quantitation of the naturally occurring retinoids: retinoic acid, retinol, and retinyl esters. An octadecylsilane column (Waters mu Bondapak C18) is used, with gradient elution from methanol--water (80:20) (solvent A) to 70% or 100% methanol--tetrahydrofuran (50:50) (solvent B) at 2.0 ml/min; detection is by absorbance at 325 nm. Analysis can be completed, with return to starting conditions, in 25-30 min. The method is inherently flexible: retinyl esters can be eluted as a group, with little resolution, by gradient to 100% solvent B, or mostly resolved by gradient to 70% solvent B; separation of retinoids more polar than retinoic acid can be achieved by use of greater proportions of water in solvent A. The separation of vitamin A compounds from extracts of human, rat, and pig liver and from rat kidney by this technique is described.

[Characteristics of a case of hepatic fructose-1,6-diphosphatase deficiency]

The authors report a new case of hepatic fructose-1.6-diphosphatase deficiency, diagnosed in a 14 month-old girl on the occasion of an episode of prostration associated with acidosis, hyperlactacidemia and hypoglycemia without hepatomegaly. The unusual features of this case, especially the glucagon induced hyperglycemia after a 12 hour fast, emphasize the clinical and biological polymorphism of this enzymopathy.

Relation of the relative dose response to liver concentrations of vitamin A in generally well-nourished surgical patients

In 12 adult, generally well-nourished, surgical patients, liver vitamin A concentrations obtained by the analysis of liver biopsies were compared with the relative dose response ( RDR ). RDR is defined as the percentage increase in plasma retinol level relative to the plasma retinol level 5 h after the oral administration of a standard oral dose (450 micrograms) of retinyl acetate. Liver vitamin A values, expressed as retinol, and corresponding RDR values were 14 micrograms/g (28%), 30 micrograms/g (15%), and 58 to 434 micrograms/g (0 to 12%). Other indicators of vitamin A nutriture, which did not correlate with liver vitamin A concentrations in this group, were serum retinol level, serum retinol-binding protein concentration, and the percentage saturation of serum retinol-binding protein. The relative distribution of fatty acyl esters in liver retinyl ester did not change with total liver reserves. The relative percentage of retinol to total liver vitamin A, however, was higher (greater than 5%) when reserves were less than or equal to 30 micrograms/g. Although the RDR cutoff point of greater than 14% suggested earlier by others is in reasonable accord with our results, a somewhat higher RDR cutoff value (possibly 20%) may agree better with the suggested criterion of a liver vitamin A concentration of 20 micrograms/g, expressed as retinol, as a minimally adequate reserve.

The correlation between liver vitamin A concentrations in micro- (needle biopsy) and macrosamples of human liver specimens obtained at autopsy

A technique is described for the analysis by gradient-elution reverse-phase high-pressure liquid chromatography of vitamin A at 325 nm in small liver samples taken by needle biopsy. This assay, in contrast to previous procedures, allows rapid separation and quantitation of approximately 0.1 microgram retinol and retinyl esters, requires only 7 mg liver sample, and separates groups of retinyl esters. Vitamin A values determined in needle biopsy samples (7 to 70 mg) and in gross samples (1 to 6.3 g) of the same 24 autopsy specimens correlated well (R = 0.96) over the range 1 to 400 micrograms vitamin A per g liver. The ratio of total vitamin A values in micro- and macrosamples was 1.09 +/- 0.46 (SD). Total vitamin A values in macrosamples of liver determined by high-pressure liquid chromatography and by a differential spectrophotometric assay also correlated well (R = 0.91). Under suitable clinical conditions, the procedure should be useful in validating indirect techniques for assessing vitamin A status.

[Heterogeneity of leucinosis. Correlations between clinical manifestations, protein tolerance and enzyme deficiency]

Maple syrup urine disease (MSUD) is an inborn error of branched-chain aminoacid (BCAA) catabolism due to a defect of BC ketoacid decarboxylation. Beside the classical form of the disease, general variant forms have been recently reported. From our personal experience in 21 patients consisting of 14 patients with classical MSUD and 7 patients with "variant" forms (1 intermittent, 2 subacute forms, 1 lipoamide dehydrogenase deficiency and 3 composite heterozygotes), we tried to correlate clinical features with protein tolerance and enzyme activity. All classical forms share an acute neonatal presentation, with a low leucine tolerance (m +/- SD = 465 +/- 88 mg per day), and a very low enzyme activity (m +/- SD = 2.5 +/- 1.5% of controls), mild variations being consistent with a possible polyallelism within this group. All "variant" forms share a late onset with a reasonable leucine tolerance (2-3 grams per day) and a fair enzyme activity, ranging from 7 to 20% of controls. However, no strict correlation could be found between the severity of the outcome and the extent of the residual enzyme activity, since acute episodes or chronic deterioration occurred even in "variants", irrespective of the level of their enzyme activity. Finally, our data suggest that variant forms could result from a composite heterozygotism, combining heterozygotism for the gene of classical MSUD and heterozygotism for a "petite" mutation, undetectable when isolated. The occurrence of classical MSUD and "variant" forms of the disease within a single family of our series further supports this hypothesis.

[Acute cerebral edema complicating therapy for diabetic ketoacidosis in children ]

Cerebral edema complicating treatment of diabetic ketoacidosis does not seen to be very rare. This neurologic complication, which was observed in 3 cases, presents similarly in all patients, occurs mainly in children and adolescents and is usually lethal. Its mechanism has not been clearly explained yet. Various etiologic factors have been considered; sodium depletion, rapid infusion of hypotonic solutions and rapid fall of plasma glucose level might have a deleterious effect. On the basis of these data, some preventive therapeutic measures are proposed.

[Emergency treatment of inborn amino errors of amino acid metabolism detected in the neonatal period]

The indications and effects of exchange transfusion, peritoneal dialysis, osmotic diuresis and early feeding have been studied in 28 children with inborn errors of aminoacid metabolism presenting in the neonatal period. Exchange-transfusion has only a transitory and incomplete effect but it is simple and quick. Peritoneal dialysis has a remarkable and often life-saving effect because the blood levels of toxic metabolites are reduced very effectively in organic acidaemias. However the rate of removal may decline if plasma concentrations fall below a critical level (1.2 mmol/L foor leucine). If the dialysis is prolonged for more than 36 hours it may cause hypoprotidaemia. Osmotic diuresis increases the 45 ml/min. However it is of little elimination of methylmalonic acid because the renal clearance is between 15 and 45 ml/min. However it is of little value in maple syrup urine disease, propionic acidaemia or isovaleric acidaemia because the renal clearance of the toxic metabolites is so low. The early re-introduction of low protein high calorie of a low protein and high calorie diet by continuous intragastric feeding is very important. The authors propose a protocol for the treatment of babies presenting inborn errors of aminoacid metabolism in the neonatal period. Peritoneal dialysis should be started as soon as the diagnosis is considered and continued for 24 to 36 hours. An exchange of transfusion shold be undertaken before and after the dialysis, together with an osmotic diuresis if appropriate. Continuous enteral feeding should be given, the quantity being adjusted to the baby's requirements.