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Genetic disorders are a leading contributor to mortality in neonatal and pediatric intensive care units (ICUs). Rapid whole-genome sequencing (rWGS)-based rapid precision medicine (RPM) is an intervention that has demonstrated improved clinical outcomes and reduced costs of care. However, the feasibility of broad clinical deployment has not been established. The objective of this study was to implement RPM based on rWGS and evaluate the clinical and economic impact of this implementation as a first line diagnostic test in the California Medicaid (Medi-Cal) program. Project Baby Bear was a payor funded, prospective, real-world quality improvement project in the regional ICUs of five tertiary care children's hospitals. Participation was limited to acutely ill Medi-Cal beneficiaries who were admitted November 2018 to May 2020, were

Penny Harvey and Hannah Knox, Roads: An Anthropology of Infrastructure and Expertise (Ithaca, NY: Cornell University Press, 2015), 264 pp., 16 illustrations, $26.95 (paperback)Noel B. Salazar and Kiran Jayaram, eds., Keywords of Mobility: Critical Engagements (New York: Berghahn Books, 2016), 196 pp., $90 (hardback)Lutz Koepnick, On Slowness: Toward an Aesthetic of the Contemporary (New York: Columbia University Press, 2014), 336 pp., 43 illustrations, $40 (hardback)Gérard Duc, Olivier Perroux, Hans-Ulrich Schiedt, and François Walter, eds., Histoire des transports et de la mobilité: Entre concurrence modale et coordination (de 1918 à nos jours) [Transport and mobility history: Between modal competition and coordination (from 1918 to the present)] (Neuchâtel: Editions Alphil-Presses Universitaires Suisses, 2014), 462 pp., $54 (paperback)Kimberley Skelton, The Paradox of Body, Building and Motion in Seventeenth- Century England (Manchester: Manchester University Press, 2015), 204 pp., 60 illustrations, £70 (hardback)Ruth Oldenziel, Martin Emanuel, Adri Albert de la Bruhèze, and Frank Veraart, eds., Cycling Cities: The European Experience—Hundred Years of Policy and Practice (Eindhoven: Foundation for the History of Technology, 2016), 256 pp., 100 illustrations. €37.50 (hardback)Glen Norcliffe, Critical Geographies of Cycling: History, Political Economy and Culture (London: Routledge, 2015), 290 pp., 24 illustrations, $119.95 (hardback)Hod Lipson and Melba Kurman, Driverless: Intelligent Cars and the Road Ahead (Cambridge, MA: MIT Press, 2016), 328 pp., 31 illustrations, $29.95 (hardback)Mathieu Flonneau, Léonard Laborie, and Arnaud Passalacqua, eds., Les transports de la démocratie: Approche historique des enjeux politiques de la mobilité [The transport of democracy: A historical approach to the political issues of mobility] (Rennes: Presses Universitaires de Rennes, 2014), 224 pp., €19 (paperback)Erik M. Conway, Exploration and Engineering: The Jet Propulsion Laboratory and the Quest for Mars (Baltimore: Johns Hopkins University Press, 2015), 416 pp., 21 illustrations, $32.95 (paperback)Hariton Pushwagner, Soft City (New York: New York Review Books, 2016), 160 pp., $35 (hardback)

Cryptochromes are evolutionarily conserved blue light receptors with many roles throughout plant growth and development. They undergo conformational changes in response to light enabling interaction with multiple downstream signaling partners. Recently, it has been shown that cryptochromes also synthesize reactive oxygen species (ROS) in response to light, suggesting the possibility of an alternate signaling mechanism. Here we show by fluorescence imaging and microscopy that H202 and ROS accumulate in the plant nucleus after cryptochrome activation. They induce ROS-regulated transcripts including for genes implicated in pathogen defense, biotic and abiotic stress. Mutant cryptochrome alleles that are non-functional in photomorphogenesis retain the capacity to induce ROS-responsive phenotypes. We conclude that nuclear biosynthesis of ROS by cryptochromes represents a new signaling paradigm that complements currently known mechanisms. This may lead to novel applications using blue light induced oxidative bursts to prime crop plants against the deleterious effects of environmental stresses and toxins.

International audience; Cryptochromes are evolutionarily conserved blue-light absorbing flavoproteins which participate in many important cellular processes including in entrainment of the circadian clock in plants, Drosophila and humans. Drosophila melanogaster cryptochrome (DmCry) absorbs light through a flavin (FAD) cofactor that undergoes photoreduction to the anionic radical (FAD(center dot-)) redox state both in vitro and in vivo. However, recent efforts to link this photoconversion to the initiation of a biological response have remained controversial. Here, we show by kinetic modeling of the DmCry photocycle that the fluence dependence, quantum yield, and half-life of flavin redox state interconversion are consistent with the anionic radical (FAD(center dot-)) as the signaling state in vivo. We show by fluorescence detection techniques that illumination of purified DmCry results in enzymatic conversion of molecular oxygen (O-2) to reactive oxygen species (ROS). We extend these observations in living cells to demonstrate transient formation of superoxide (O-2(center dot-)), and accumulation of hydrogen peroxide (H2O2) in the nucleus of insect cell cultures upon DmCry illumination. These results define the kinetic parameters of the Drosophila cryptochrome photocycle and support light-driven electron transfer to the flavin in DmCry signaling. They furthermore raise the intriguing possibility that light-dependent formation of ROS as a byproduct of the cryptochrome photocycle may contribute to its signaling role.

���� ��� The article argues that while introductory women and gender studies courses typically take social construction theory as foundational, their textbooks, supplemental materials, and teaching strategies simultaneously rely on a definition of “woman” that assumes particular body parts. Such a linkage elides the existence and particularities of transgender and gender-nonconforming bodies and subjects on the one hand, yet posits them as exceptions on the other. This combination stabilizes the normativity of hegemonic sex and gender embodiments by naturalizing nontransgender bodies. Rather than simply arguing for greater inclusion of trans subjects under the sign of woman or man, the article suggests that careful attention to the positioning of transgender bodies necessitates a broad theoretical reframing of how women’s studies textbooks and curriculum are designed, and how gendered bodies more broadly are taught and conceptualized.

Objective To quantify intercenter cost variation for perinatal hypoxic ischemic encephalopathy (HIE) treated with therapeutic hypothermia across children's hospitals. Study design Prospectively collected data from the Children's Hospitals Neonatal Database and Pediatric Health Information Systems were linked to evaluate intercenter cost variation in total hospitalization costs after adjusting for HIE severity, mortality, length of stay, use of extracorporeal support or nitric oxide, and ventilator days. Secondarily, costs for intensive care unit bed, electroencephalography (EEG), and laboratory and neuroimaging testing were also evaluated. Costs were contextualized by frequency of favorable (survival with normal magnetic resonance imaging) and adverse (death or need for gastric tube feedings at discharge) outcomes to identify centers with relative low costs and favorable outcomes. Results Of the 822 infants with HIE treated with therapeutic hypothermia at 19 regional neonatal intensive care units, 704 (86%) survived to discharge. The median cost/case for survivors was $58 552 (IQR $32 476-$130 203) and nonsurvivors $29 760 (IQR $16 897-$61 399). Adjusting for illness severity and select interventions, intercenter differences explained 29% of the variation in total hospitalization costs. The widest cost variability across centers was EEG use, although low cost and favorable outcome centers ranked higher with regards to EEG costs. Conclusions There is marked intercenter cost variation associated with treating HIE across regional children's hospitals. Our investigation may help establish references for cost and enhance quality improvement and resource utilization projects related to HIE.

Background and Purpose— The etiology of stroke in children with sickle cell anemia (SCA) is complex and poorly understood. Growing evidence suggests that genetic factors beyond the sickle cell mutation influence stroke risk in SCA. We previously reported risk associations with polymorphisms in several proinflammatory genes in SCA children with ischemic stroke. The aim of this replication study was to confirm our previous findings of associations between the TNF(−308) G/A, IL4R 503 S/P, and ADRB2 27 Q/E polymorphisms and large vessel stroke risk. Methods— Using previously collected MRA data, we assessed an independent population of SCA children from the multicenter Stroke Prevention Trial in Sickle Cell Anemia (STOP) for the presence or absence of large vessel stenosis. Samples were genotyped for 104 polymorphisms among 65 candidate vascular disease genes. Genotypic associations with risk of large vessel stroke were screened using univariable analysis and compared with results from our original study. Joint analysis of the 2 study populations combined was performed using multivariable logistic regression. Results— A total of 96 children (49 MRA-positive, 47 MRA-negative) were included in this study. Of the SNP associations previously identified in the original study, the TNF(−308) G/A association with large vessel stroke remained significant and the IL4R 503 S/P variant approached significance in the joint analysis of the combined study populations. Consistent with our original findings, the TNF(−308) GG genotype was associated with a >3-fold increased risk of large vessel disease (OR=3.27; 95% CI=1.6, 6.9; P =0.006). Unadjusted analyses also revealed a previously unidentified association between the LTC4S(−444) A/C variant and large vessel stroke risk. Conclusions— Similar findings in 2 independent study populations strongly suggest that the TNF(−308) G/A promoter polymorphism is a clinically important risk factor for large vessel stroke in children with SCA. The previously observed association with the IL4R 503 S/P variant and the novel association with the LTC4S(−444) A/C variant suggest that these loci may also contribute to large vessel stroke risk in children with SCA.

International audience; Cryptochromes are blue-light absorbing flavoproteins with many important signaling roles in plants, including in de-etiolation, development, and stress response. They interact with downstream signaling partners such as transcription factors and components of the proteasome, and thereby alter regulation of nuclear gene expression in a light dependent manner. In a prior study, it has also been shown that Arabidopsis cry1 activation by blue light results in direct enzymatic conversion of molecular oxygen (O2) to ROS (reactive oxygen species) in vivo leading to cell death in overexpressing lines. Here we extend these observations to show that Atcry2 is translocated from the cytosol to the nucleus in response to blue light illumination, resulting in nuclear accumulation of ROS in expressing insect cell cultures. These observations suggest that ROS formation may represent a novel means of signaling by Atcry2 distinct from, and perhaps complementary to, the currently known mechanism of light-mediated conformational change.

The effects of physical characteristice and cell wall enzymatic activites of several strawberry cultivars were investigated for possible industrial use. The enzymes study showed that the softed varieties had the highest pectin methylesterase (PME) and polygalacturonase (PC) activities. Differences in alcohal-insoluble pectin, water-soluble pectin, and parietal residue compositions were observed between Darsanga (firm fruit) and Senga sengana (soft fruit). Finally, the study of pectin composition of Darsanga and Senga sengana Indicated that the softest fruit had the highest water-soluble pectin content. The measurement of fruit PME activity permitted a preliminary screcning of frult maturity characteristics. strawberry, Fragaria x ananassa Duch, firmness, drip loss, jam cookingm, pectin methylesterase, polygalacturonase, β-galactosidase, pectin composition.

Cryptochromes are widespread blue-light absorbing flavoproteins with important signaling roles. In plants they mediate de-etiolation, developmental and stress responses resulting from interaction with downstream signaling partners such as transcription factors and components of the proteasome. Recently, it has been shown that Arabidopsis cry1 activation by blue light also results in direct enzymatic conversion of molecular oxygen (O2) to reactive oxygen species (ROS) and hydrogen peroxide (H2O2) in vitro. Here we explored whether direct enzymatic synthesis of ROS by Arabidopsis cry1 can play a physiological role in vivo. ROS formation resulting from cry1 expression was measured by fluorescence assay in insect cell cultures and in Arabidopsis protoplasts from cryptochrome mutant seedlings. Cell death was determined by colorimetric assay. We found that ROS formation results from cry1 activation and induces cell death in insect cell cultures. In plant protoplasts, cryptochrome activation results in rapid increase in ROS formation and cell death. We conclude that ROS formation by cryptochromes may indeed be of physiological relevance and could represent a novel paradigm for cryptochrome signaling. Fil: Consentino, Laurent. Université Pierre et Marie Curie; Francia Fil: Lambert, Stefan. Université Pierre et Marie Curie; Francia Fil: Martino, Carlos. Université Pierre et Marie Curie; Francia. University of Florida; Estados Unidos Fil: Jourdan, Nathalie. Université Pierre et Marie Curie; Francia Fil: Bouchet, Pierre Etienne. Université Pierre et Marie Curie; Francia Fil: Witczak, Jacques. Université Pierre et Marie Curie; Francia Fil: Castello, Pablo Raul. Universidad de Belgrano. Facultad de Ciencias Exactas y Naturales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Université Pierre et Marie Curie; Francia Fil: El-Esawi, Mohamed. Université Pierre et Marie Curie; Francia. Tanta University; Egipto Fil: Corbineau, Francoise. Université Pierre et Marie Curie; Francia Fil: d'Harlingue, Alain. Université Pierre et Marie Curie; Francia Fil: Ahmad, Margaret. Université Pierre et Marie Curie; Francia. Universidad Xavier; Estados Unidos

Neoxanthin, a precursor of the plant hormone abscisic acid, is an allenic xanthophyll recognized as the last product of carotenoid synthesis in green plants. A cDNA for neoxanthin synthase (NSY) was isolated from tomato using a molecular approach based on the mechanistic and structural similarities of NSY to two other closely related carotenogenic enzymes, lycopene cyclase (LCY) and capsanthin-capsorubin synthase (CCS). The identified tomato NSY cDNA (T.NSY) encodes a 56-kDa plastid-targeted protein that when expressed in Escherichia coli, catalyzes the conversion of violaxanthin to neoxanthin. In tobacco leaves that transiently express T.NSY, an increase in neoxanthin content with a concomitant decrease in violaxanthin is observed. NSY is structurally similar to LCY and CCS. However, in Cyanobacteria, the generally accepted progenitor of plastids, both CCS and NSY are absent while LCY is present. LCY catalyzes a simplified version of the reaction catalyzed by NSY and CCS suggesting that these two enzymes were remodeled from LCY during higher plant evolution to create new forms of oxidized carotenoids.

Isopentenyl diphosphate (IPP), which is produced from mevalonic acid or other nonmevalonic substrates, is the universal precursor of isoprenoids in nature. Despite the presence of several isoprenoid compounds in plastids, enzymes of the mevalonate pathway leading to IPP formation have never been isolated or identified to our knowledge. We now describe the characterization of two pepper (Capsicum annuum L.) cDNAs, CapTKT1 and CapTKT2, that encode transketolases having distinct and dedicated specificities. CapTKT1 is primarily involved in plastidial pentose phosphate and glycolytic cycle integration, whereas CapTKT2 initiates the synthesis of isoprenoids in plastids via the nonmevalonic acid pathway. From pyruvate and glyceraldehyde-3-phosphate, CapTKT2 catalyzes the formation of 1-deoxy-xylulose-5-phosphate, the IPP precursor. CapTKT1 is almost constitutively expressed during the chloroplast-to-chromoplast transition, whereas CapTKT2 is overexpressed during this period, probably to furnish the IPP necessary for increased carotenoid biosynthesis. Because deoxy-xylulose phosphate is shared by the plastid pathways of isoprenoid, thiamine (vitamin B1), and pyridoxine (vitamin B6) biosynthesis, our results may explain why albino phenotypes usually occur in thiamine-deficient plants.

To dissect the mechanism by which carotenoid hydroxylases catalyze xanthophyll formation, we have cloned two pepper cDNAs encoding beta-cryptoxanthin and zeaxanthin biosynthetic enzymes. Using an in vitro system, we find that both enzymes are ferredoxin dependent and that their activity is strongly inhibited by iron chelators such as o-phenanthroline or 8-hydroxyquinoline. This suggests the transfer of a reducing equivalent from NADPH to the hydroxylase via ferredoxin and the involvement of an iron activated oxygen insertion process. Based on sequence analysis, the putative histidine clusters involved in the iron coordination were identified and their roles evaluated. Following site-directed mutagenesis of the identified histidine residues hydroxylase activity was totally inactivated. Collectively, our data indicate that carotenoid hydroxylases belong to a new class of diiron proteins structurally related to membrane fatty acid desaturases. Mechanistically, both types of enzymes exploit iron activated oxygen to break the C-H bond with concomitant formation of double bond or oxygen insertion. We propose that the same mechanism operates for beta-carotene ketolase and probably for other carotenoid oxygenases as well.

The addition of phytyl side chain to chlorophylls, tocopherols and phylloquinone is prerequisite to their integration into plastid membranes. We have cloned a cDNA encoding a pre-geranylgeranyl reductase from Arabidopsis thaliana. The deduced primary structure predicts a mature size with a molecular mass of 47 kDa and displays a characteristic dinucleotide binding domain. Geranylgeranyl reductase expressed in Escherichia coli sequentially catalyzes the reduction of geranylgeranyl-chlorophyll a into phytyl-chlorophyll a as well as the reduction of free geranylgeranyl diphosphate into phytyl diphosphate. Due to its multifunctionality and weak hydrophobicity, we suggest that in plastid the same geranylgeranyl reductase is recruited into the chlorophyll, the tocopherol and the phylloquinone pathways. The geranylgeranyl reductase gene is up-regulated during etioplast to chloroplast and chloroplast to chromoplast development.

Later steps of carotenoid biosynthesis catalyzed by cyclase enzymes involve the formation of alpha, beta, and kappa-rings. Examination of the primary structure of lycopene beta-cyclase revealed 55% identity with that of antheraxanthin kappa-cyclase. Recombinant lycopene beta-cyclase afforded only beta-carotene, while recombinant antheraxanthin kappa-cyclase catalyzed the formation of beta-carotene from lycopene as well as the conversion of antheraxanthin into the kappa-carotenoid capsanthin. Since the formation of beta- and kappa-rings involves a transient carotenoid carbocation, this suggests that both cyclases initiate and/or neutralize the incipient carbocation by similar mechanisms. Several amine derivatives protonated at physiological pH were used to examine the molecular basis of this phenomenon. The beta-and kappa-cyclases displayed similar inhibition patterns. Affinity or photoaffinity labeling using p-dimethylamino-benzenediazonium fluoroborate, N,N-dimethyl-2-phenylaziridinium, and nicotine irreversibly inactivated both cyclase enzymes. Photoaffinity labeling using [3H]nicotine followed by radiosequence analysis and site-directed mutagenesis revealed the existence of two cyclase domains characterized by the presence of reactive aromatic and carboxylic amino acid residues. We propose that these residues represent the "negative point charges" involved in the coordination of the incipient carotenoid carbocations.

Pepper (Capsicum annuum) β-cyclohexenyl xanthophyll epoxidase cDNA was cloned and the corresponding enzyme overexpressed and purified from Escherichia coli, for investigation of its catalytic activity. The recombinant protein did not directly accept NADPH for epoxidation of cyclohexenyl carotenoids, nor did it operate according to a peroxygenase-based mechanism. Instead, the reducing power of NADPH was transferred to the epoxidase via reduced ferredoxin as shown by reconstitution of epoxidase activity in the presence of NADPH, ferredoxin oxidoreductase, and ferredoxin. Bacterial rubredoxin could be substituted for ferredoxin. The pepper epoxidase acted specifically on the β-ring of xanthophylls such as β-cryptoxanthin, zeaxanthin, and antheraxanthin. The proposed reaction mechanism for epoxidation involves the formation of a transient carbocation. This characteristic allows selective inhibition of the epoxidase activity by different nucleophilic diethylamine derivatives, p-dimethylaminobenzenediazonium fluoroborate and N,N-dimethyl-2-phenylaziridinium. It was also shown that the epoxidase gene was up-regulated during oxidative stress and when chloroplasts undergo differentiation into chromoplasts in pepper fruit.

Mycotoxins are produced by secondary metabolism of various fungal species. Numerous studies were performed on the occurrence of the mycotoxins in raw commodities and foodstuffs. These studies were carried out on account of their high toxicity and the possible risk they can present for the health of the consumers. The purpose of this paper is to review the occurrence of mycotoxins in fruit juices and wine.

Cysteine synthase (O-acetylserine sulfhydrylase) has been purified to homogeneity from bell pepper (Capsicum annuum) fruit chromoplasts. This enzyme consists of two subunits of 35 kDa. Immunocytochemical localization experiments confirmed the plastid location of this enzyme. A full-length cDNA was isolated from an expression library of C. annuum. The deduced peptide sequence revealed high similarity between the C. annuum cysteine synthase and its bacterial counterparts. In vitro transcription and translation of the cDNA and subsequent import experiments demonstrated that the encoded cysteine synthase is located in the plastids. The steady-state level of the cysteine synthase mRNA is almost constant in dark-grown hypocotyls, leaves, and fruits. However, a slight increase in this mRNA level was detected during fruit development (when the 25 S rRNA was taken as an internal standard). Similarly, the cysteine synthase activity in plastids was found to increase during fruit development and reaches the highest levels in the chromoplasts of red fruits. To address the physiological role of this phenomenon, we have shown that cysteine is engaged in the active metabolism of glutathione. Thus, in connection with the previous demonstration of an active tocopherol metabolism, it is concluded that differentiation of chloroplast to chromoplast in C. annuum involves an active synthesis of potential antioxidants or redox modulators.

Achieving vitamin E sufficiency in the premature infant during parenteral nutrition requires early intravenous vitamin E supplementation. The optimal dose of intravenously administered vitamin E has not been determined. The antioxidant properties of vitamin E have led to its prophylactic use in the prevention of retinopathy of prematurity and intraventricular hemorrhage in premature infants, with variable results.1-4 Risks associated with pharmacologic doses of vitamin E include necrotizing enterocolitis and sepsis, and such adverse effects may be related to high plasma vitamin E levels.3 A plasma vitamin E level of 0.5 mg/dL is considered sufficient in premature infants.5 Johnson recomended that vitamin E levels in premature infants be maintained in a range of 1.0 to 3.0 mg/dL.

The nature of isoprenoids synthesized in plants is primarily determined by the specificity of prenyltransferases. Several of these enzymes have been characterized at the molecular level. The compartmentation and molecular regulation of geranyl diphosphate (GPP), the carbon skeleton that is the backbone of myriad monoterpene constituents involved in plant defence, allelopathic interactions and pollination, is poorly understood. We describe here the cloning and functional expression of a GPP synthase (GPPS) from Arabidopsis thaliana. Immunohistological analyses of diverse non-secretory and secretory plant tissues reveal that GPPS and its congeners, monoterpene synthase, deoxy-xylulose phosphate synthase and geranylgeranyl diphosphate synthase, are equally compartmentalized and distributed in non-green plastids as well in chloroplasts of photosynthetic cells. This argues that monoterpene synthesis is not solely restricted to specialized secretory structures but can also occur in photosynthetic parenchyma. These data provide new information as to how monoterpene biosynthesis is compartmentalized and induced de novo in response to biotic and abiotic stress in diverse plants.

Neoxanthin, a precursor of the plant hormone abscisic acid, is an allenic xanthophyll recognized as the last product of carotenoid synthesis in green plants. A cDNA for neoxanthin synthase (NSY) was isolated from tomato using a molecular approach based on the mechanistic and structural similarities of NSY to two other closely related carotenogenic enzymes, lycopene cyclase (LCY) and capsanthin-capsorubin synthase (CCS). The identified tomato NSY cDNA (T.NSY) encodes a 56-kDa plastid-targeted protein that when expressed in Escherichia coli, catalyzes the conversion of violaxanthin to neoxanthin. In tobacco leaves that transiently express T.NSY, an increase in neoxanthin content with a concomitant decrease in violaxanthin is observed. NSY is structurally similar to LCY and CCS. However, in Cyanobacteria, the generally accepted progenitor of plastids, both CCS and NSY are absent while LCY is present. LCY catalyzes a simplified version of the reaction catalyzed by NSY and CCS suggesting that these two enzymes were remodeled from LCY during higher plant evolution to create new forms of oxidized carotenoids.

Pepper (Capsicum annuum) beta-cyclohexenyl xanthophyll epoxidase cDNA was cloned and the corresponding enzyme overexpressed and purified from Escherichia coli, for investigation of its catalytic activity. The recombinant protein did not directly accept NADPH for epoxidation of cyclohexenyl carotenoids, nor did it operate according to a peroxygenase-based mechanism. Instead, the reducing power of NADPH was transferred to the epoxidase via reduced ferredoxin as shown by reconstitution of epoxidase activity in the presence of NADPH, ferredoxin oxidoreductase, and ferredoxin. Bacterial rubredoxin could be substituted for ferredoxin. The pepper epoxidase acted specifically on the beta-ring of xanthophylls such as beta-cryptoxanthin, zeaxanthin, and antheraxanthin. The proposed reaction mechanism for epoxidation involves the formation of a transient carbocation. This characteristic allows selective inhibition of the epoxidase activity by different nucleophilic diethylamine derivatives, p-dimethylaminobenzenediazonium fluoroborate and N,N-dimethyl-2-phenylaziridinium. It was also shown that the epoxidase gene was up-regulated during oxidative stress and when chloroplasts undergo differentiation into chromoplasts in pepper fruit.

The properties of iv-fat emulsions are similar to those of triglyceride-rich plasma lipoproteins and rapidly hydrolyzed by lipoprotein lipase. Neonates frequently do not tolerate iv-fat because of low levels of the key enzymes for fat metabolism.We examined the effect of iv-fat therapy on LDL subclass distribution of 20 neonates unable to tolerate enteral feeding.Particle size was determined by non-denaturing gradient gel electrophoresis.The LDL size distribution profiles at baseline showed unexpected diversity in the position of the major lipoprotein peak with three different profiles identified by peak position; profile I with a major peak of large-sized LDL (26.3-28.2 nm), profile II with a major peak at 25.2-26.7 nm and profile III with a major peak of small-sized particles (24.9-25.6 nm). None of the profiles fit the classical LDL pattern A or B found in adult plasma since the skewness associated with the adult pattern was not present. With iv fat feeding and enteral nutrition, no major shift in peak position was observed, even though plasma triglyceride and apo B concentrations increased suggesting that there was an increased number of LDL particles rather than an increase in the size of particles.The constancy of the LDL peak position in the face of increases in plasma triglyceride and apo B concentrations during iv fat and the onset of enteral nutrition in neonates suggests that other metabolic events, such as hormone status and lipid and transfer protein activities need to be considered.

International audience