Eyes on the Future: Inspiring Latino Middle School Youth to Pursue Careers in STEM Through Early Interactive Science Programming.

BACKGROUND: Given the need for a diverse health care workforce, efforts must be made early in their education to support underrepresented minorities in medicine and the science, technology, engineering, and mathematics (STEM) fields. METHODS: The Eyes on the Future program introduces underrepresented minority 8th grade students to science and medicine via interactive science-based programming and mentorship by medical and graduate students. Program impact was evaluated using pre- and post-program surveys. RESULTS: Of 25 participating students, 24 and 22 responded to pre- and post-program surveys, respectively. Students showed strong interest in science concepts and STEM careers, with high, positively correlated, and statistically similar pre- and post-program survey responses. DISCUSSION: The Eyes on the Future program was well-received and represents a step towards addressing barriers to STEM careers faced by underrepresented minority students.

Non-Nutritive Sweeteners Acesulfame Potassium and Sucralose Are Competitive Inhibitors of the Human P-glycoprotein/Multidrug Resistance Protein 1 (PGP/MDR1).

Non-nutritive sweeteners (NNS) are popular sugar replacements used in foods, beverages, and medications. Although NNS are considered safe by regulatory organizations, their effects on physiological processes such as detoxification are incompletely understood. Previous studies revealed that the NNS sucralose (Sucr) altered P-glycoprotein (PGP) expression in rat colon. We also demonstrated that early-life exposure to NNS Sucr and acesulfame potassium (AceK) compromises mouse liver detoxification. Building upon these initial discoveries, we investigated the impact of AceK and Sucr on the PGP transporter in human cells to assess whether NNS influence its key role in cellular detoxification and drug metabolism. We showed that AceK and Sucr acted as PGP inhibitors, competing for the natural substrate-binding pocket of PGP. Most importantly, this was observed after exposure to concentrations of NNS within expected levels from common foods and beverage consumption. This may suggest risks for NNS consumers, either when taking medications that require PGP as the primary detoxification transporter or during exposure to toxic compounds.

Multiple molecular mechanisms are involved in the activation of the kidney sodium-chloride cotransporter by hypokalemia.

Low potassium intake activates the kidney sodium-chloride cotransporter (NCC) whose phosphorylation and activity depend on the With-No-Lysine kinase 4 (WNK4) that is inhibited by chloride binding to its kinase domain. Low extracellular potassium activates NCC by decreasing intracellular chloride thereby promoting chloride dissociation from WNK4 where residue L319 of WNK4 participates in chloride coordination. Since the WNK4-L319F mutant is constitutively active and chloride-insensitive in vitro, we generated mice harboring this mutation that displayed slightly increased phosphorylated NCC and mild hyperkalemia when on a 129/sv genetic background. On a low potassium diet, upregulation of phosphorylated NCC was observed, suggesting that in addition to chloride sensing by WNK4, other mechanisms participate which may include modulation of WNK4 activity and degradation by phosphorylation of the RRxS motif in regulatory domains present in WNK4 and KLHL3, respectively. Increased levels of WNK4 and kidney-specific WNK1 and phospho-WNK4-RRxS were observed in wild-type and WNK4L319F/L319F mice on a low potassium diet. Decreased extracellular potassium promoted WNK4-RRxS phosphorylation in vitro and ex vivo as well. These effects might be secondary to intracellular chloride depletion, as reduction of intracellular chloride in HEK293 cells increased phospho-WNK4-RRxS. Phospho-WNK4-RRxS levels were increased in mice lacking the Kir5.1 potassium channel, which presumably have decreased distal convoluted tubule intracellular chloride. Similarly, phospho-KLHL3 was modulated by changes in intracellular chloride in HEK293 cells. Thus, our data suggest that multiple chloride-regulated mechanisms are responsible for NCC upregulation by low extracellular potassium.

Hidranencefalia congénita: reporte de un adolescente en el norte de México / Congenital hydranencephaly: report of an adolescent in the north of Mexico

Fundamento: la hidranencefalia es la ausencia total o casi total de los hemisferios cerebrales con persistencia de líquido cefalorraquídeo, que afecta a individuos de todo el mundo sin importar su género u origen étnico. No existe un tratamiento eficaz y curativo y la gran mayoría de los pacientes mueren antes de alcanzar el tercer año de vida, aunque en algunas excepciones pueden llegar a la mayoría de edad, donde se requiere siempre del apoyo multidisciplinario. Objetivo: presentar el caso de un varón adolescente con hidranencefalia congénita. Caso clínico: paciente masculino de 11 años de edad ingresado en el centro a los cinco años referido como holoprosencefalia. Fue obtenido por cesárea a las 38 semanas de gestación por ruptura de membranas con somatometría normal y Apgar de cinco, requirió maniobras de reanimación neonatal avanzada. A los 30 días su perímetro cefálico aumentó a 39 cm, siguió en aumento hasta alcanzar los 54 cm a los 6 meses de edad. No presentó control cefálico ni control del tronco, tampoco fue capaz de realizar bipedestación, ni desarrolló lenguaje ni emisión de sonidos. Una tomografía cerebral realizada a su ingreso al centro reveló islotes de parénquima cerebral con meninges y línea media, lo que correspondió a una hidranencefalia. Se presentó el caso por la baja frecuencia que, los pacientes con hidranencefalia alcanzan la adolescencia. Conclusiones: la hidranencefalia es una enfermedad que suele ser letal, y los casos que logran sobrevivir tienen secuelas neurológicas graves y discapacitantes. Aunque se conocen algunos síndromes genéticos asociados a hidranencefalia, la mayoría de los casos son esporádicos y sin manifestaciones externas al sistema nervioso central. Si bien, la esperanza de que el caso presentado muestre mayores avances en su desarrollo neurológico no es alentadora, las terapias física, ocupacional y pulmonar pueden permitir una mejor calidad de vida.

Background: hydranencephaly is the total or almost total absence of the cerebral hemispheres with persistent cerebrospinal fluid, which affects individuals around the world regardless of gender or ethnicity. There is no effective and curative treatment, and most patients die before reaching the third year of life, although some exceptions can come of age, always requiring multidisciplinary support. Objective: to present the case of an adolescent male with congenital hydranencephaly. Clinical case: a 11-year-old male from 11 who was admitted at the age of 5 referred to as holoprosencephaly. He was born by caesarean section at 38 weeks of gestation due to rupture of membranes with normal somatometry and Apgar 5, requiring advanced neonatal resuscitation maneuvers. At 30 days head circumference increased to 39 cm and was increasing, reaching 54 cm at 6 months of age. The patient has no control head and trunk, and he was not capable of bipedalism, or developed language or sound emission. A brain scan performed on admission revealed brain parenchyma islets and meninges, corresponding to hydranencephaly. The case is presented by the infrequency with which patients reach adolescence. Conclusions: hydranencephaly is a disease that is usually fatal, and cases that survive have severe and disabling neurological sequeles. Although some genetic syndromes associated with hydranencephaly are known, most cases are usually sporadic with no other manifestations. Though the hope that the case presented shows greater progress in their neurological development is not encouraging, physical, occupational and pulmonary therapy may allow better quality of life.

Coxiella burnetii and Leishmania mexicana residing within similar parasitophorous vacuoles elicit disparate host responses.

Coxiella burnetii is a bacterium that thrives in an acidic parasitophorous vacuole (PV) derived from lysosomes. Leishmania mexicana, a eukaryote, has also independently evolved to live in a morphologically similar PV. As Coxiella and Leishmania are highly divergent organisms that cause different diseases, we reasoned that their respective infections would likely elicit distinct host responses despite producing phenotypically similar parasite-containing vacuoles. The objective of this study was to investigate, at the molecular level, the macrophage response to each pathogen. Infection of THP-1 (human monocyte/macrophage) cells with Coxiella and Leishmania elicited disparate host responses. At 5 days post-infection, when compared to uninfected cells, 1057 genes were differentially expressed (746 genes up-regulated and 311 genes down-regulated) in C. burnetii infected cells, whereas 698 genes (534 genes up-regulated and 164 genes down-regulated) were differentially expressed in L. mexicana infected cells. Interestingly, of the 1755 differentially expressed genes identified in this study, only 126 genes (~7%) are common to both infections. We also discovered that 1090 genes produced mRNA isoforms at significantly different levels under the two infection conditions, suggesting that alternate proteins encoded by the same gene might have important roles in host response to each infection. Additionally, we detected 257 micro RNAs (miRNAs) that were expressed in THP-1 cells, and identified miRNAs that were specifically expressed during Coxiella or Leishmania infections. Collectively, this study identified host mRNAs and miRNAs that were influenced by Coxiella and/or Leishmania infections, and our data indicate that although their PVs are morphologically similar, Coxiella and Leishmania have evolved different strategies that perturb distinct host processes to create and thrive within their respective intracellular niches.

Identification of the intracellular gate for a member of the equilibrative nucleoside transporter (ENT) family.

Equilibrative nucleoside transporters of the SLC29 family play important roles in many physiological and pharmacological processes, including import of drugs for treatment of cancer, AIDS, cardiovascular, and parasitic diseases. However, no crystal structure is available for any member of this family. In previous studies we generated a computational model of the Leishmania donovani nucleoside transporter 1.1 (LdNT1.1) that captured this permease in the outward-closed conformation, and we identified the extracellular gate. In the present study we have modeled the inward-closed conformation of LdNT1.1 using the crystal structure of the Escherichia coli fucose transporter FucP and have identified four transmembrane helices whose ends close to form a predicted intracellular gate. We have tested this prediction by site-directed mutagenesis of relevant helix residues and by cross-linking of introduced cysteine pairs. The results are consistent with the predictions of the computational model and suggest that a similarly constituted gate operates in other members of the equilibrative nucleoside transporter family.

Cysteine cross-linking defines the extracellular gate for the Leishmania donovani nucleoside transporter 1.1 (LdNT1.1).

Equilibrative nucleoside transporters are a unique family of proteins that enable uptake of nucleosides/nucleobases into a wide range of eukaryotes and internalize a myriad of drugs used in the treatment of cancer, heart disease, AIDs, and parasitic infections. In previous work we generated a structural model for such a transporter, the LdNT1.1 nucleoside permease from the parasitic protozoan Leishmania donovani, using ab initio computation. The model suggested that aromatic residues present in transmembrane helices 1, 2, and 7 interact to form an extracellular gate that closes the permeation pathway in the inward-open conformation. Mutation of residues Phe-48(TM1) and Trp-75(TM2) abrogated transport activity, consistent with such prediction. In this study cysteine mutagenesis and oxidative cross-linking were combined to analyze proximity relationships of helices 1, 2, and 7 in LdNT1.1. Disulfide bond formation between introduced paired cysteines at the interface of such helices (A61C(TM1)/F74C(TM2), A61C(TM1)/G350C(TM7), and F74C(TM2)/G350C(TM7)) was analyzed by transport measurement and gel mobility shifts upon oxidation with Cu (II)-(1,10-phenanthroline)(3). In all cases cross-linking inhibited transport. However, if LdNT1.1 ligands were included during cross-linking, inhibition of transport was reduced, suggesting that ligands moved the three gating helices apart. Moreover, all paired cysteine mutants exhibited a mobility shift upon oxidation, corroborating the formation of a disulfide bond. These data support the notion that helices 1, 2, and 7 constitute the extracellular gate of LdNT1.1, thus further validating the computational model and the previously demonstrated importance of F48(TM1) and Trp-75(TM2) in tethering together helices that are part of the gate.

Purine restriction induces pronounced translational upregulation of the NT1 adenosine/pyrimidine nucleoside transporter in Leishmania major.

Leishmania and other parasitic protozoa are unable to synthesize purines de novo and are reliant upon purine nucleoside and nucleobase transporters to import preformed purines from their hosts. To study the roles of the four purine permeases NT1-NT4 in Leishmania major, null mutants in each transporter gene were prepared and the effect of each gene deletion on purine uptake was monitored. Deletion of the NT3 purine nucleobase transporter gene or both NT3 and the NT2 nucleoside transporter gene resulted in pronounced upregulation of adenosine and uridine uptake mediated by the NT1 permease and also induced up to a 200-fold enhancement in the level of the NT1 protein but not mRNA. A similar level of upregulation of NT1 was achieved in wild-type promastigotes that were transferred to medium deficient in purines. Pulse labelling and treatment of cells with the translation inhibitor cycloheximide revealed that control of NT1 expression occurs primarily at the level of translation and not protein turnover. These observations imply the existence of a translational control mechanism that enhances the ability of Leishmania parasites to import essential purines when they are present at limiting concentrations.

An ab Initio structural model of a nucleoside permease predicts functionally important residues.

Permeases belonging to the equilibrative nucleoside transporter family promote uptake of nucleosides and/or nucleobases into a wide range of eukaryotes and mediate the uptake of a variety of drugs used in the treatment of cancer, heart disease, AIDS, and parasitic infections. No experimental three-dimensional structure exists for any of these permeases, and they are not present in prokaryotes, the source of many membrane proteins used in crystal structure determination. To generate a structural model for such a transporter, the LdNT1.1 nucleoside permease from the parasitic protozoan Leishmania donovani was modeled using ab initio computation. Site-directed mutations that strongly impair transport or that alter substrate specificity map to the central pore of the ab initio model, whereas mutations that have less pronounced phenotypes map to peripheral positions. The model suggests that aromatic residues present in transmembrane helices 1, 2, and 7 may interact to form an extracellular gate that closes the permeation pathway in the inward oriented conformation. Mutation of two of these three residues abrogated transport activity, consistent with the prediction of the model. The ab initio model is similar to one derived previously using threading analysis, a distinct computational approach, supporting the overall accuracy of both models. However, significant differences in helix orientation and residue position between the two models are apparent, and the mutagenesis data suggest that the ab initio model represents an improvement regarding structural details over the threading model. The putative gating interaction may also help explain differences in substrate specificity between members of this family.

Children of alcoholics in Spain: from risk to pathology. Results from the ALFIL program.

OBJECTIVE: To identify the possible risk factors and negative outcomes associated with parental alcoholism. A secondary aim was to determine the influence of the family density of alcoholism on children of alcoholics' (COAs) psychological functioning. METHOD: A multisite epidemiological study was conducted in 8 Spanish cities, recruiting a total sample of 371 COAs (whose parents were in contact with alcohol treatment centers and accepted to participate in this study) and 147 controls (from schools in the same localities as COAs). Both groups were 6-17 years old and received a comprehensive evaluation of mental disorders (no symptoms, subclinical symptoms or clinical diagnosis for each disorder; according to DSM-IV criteria); alcohol and other substance use (none, occasional, regular and risky consumption); school achievement (low, middle and high) and other academic performance indicators (WISC-R Information and Arithmetic subtests, school support activities and failed subjects and courses). Lastly, several cognitive functions were measured by the WISC-R Similarities, Block Design and Digit Symbol subtests, the Toulouse-Piéron test and the Stroop test. Logistic regression methods were used to compare both groups and a linear regression model was used to determine the influence of the family density of alcoholism. The following confounding variables were controlled for: age, gender, socio-economic status and family cohesion. RESULTS: Children of alcoholics' were twice as likely as controls to present subclinical symptoms and four times more likely than controls to have a definite diagnosis of any mental disorder. More specifically, COAs had a significantly higher risk than controls of attention deficit disorder/hyperactivity, depression, phobias, enuresis and tics. COAs also tended to have more symptoms of generalized anxiety disorder. COAs had worse results on all the cognitive tests used and their risk of low school achievement was nine times higher than that of controls. Family density of alcoholism was significantly related to several psychiatric disorders and to low academic and cognitive performance in these children. CONCLUSION: Children of alcoholics' whose parents are in contact with treatment centers in Spain constitute a target group for selective prevention, as they have a higher risk of different negative outcomes, which mainly include attention disorders and other cognitive deficits, depression and anxiety.

Applications of computer assisted surgery and medical robotics at the ISSSTE, México: preliminary results.

We present the first results of four projects of a second phase of a Mexican Project Computer Assisted Surgery and Medical Robotics, supported by the Mexican Science and Technology National Council (Consejo Nacional de Ciencia y Tecnología) under grant SALUD-2002-C01-8181. The projects are being developed by three universities (UNAM, UAM, ITESM) and the goal of this project is to integrate a laboratory in a Hospital of the ISSSTE to give service to surgeons or clinicians of Endoscopic surgeons, urologist, gastrointestinal endoscopist and neurosurgeons.

Comprehensive examination of charged intramembrane residues in a nucleoside transporter.

Permeases of the equilibrative nucleoside transporter family mediate the uptake of nucleosides and/or nucleobases in a diverse array of eukaryotes and transport a host of drugs used for treatment of cancer, heart disease, AIDS, and parasitic infections. To identify residues that play central roles in transport function, we have systematically substituted by site-directed mutagenesis all the charged residues located within predicted transmembrane domains of the Leishmania donovani nucleoside transporter 1.1, LdNT1.1, which transports adenosine and the pyrimidine nucleosides. Substitution of three of these ten residues by uncharged amino acids resulted in loss of >95% transport activity, and we hence designated them "key" residues. These amino acids were Glu94, Lys153, and Arg404 located in transmembrane domains 2, 4, and 9, respectively. In addition, previous studies on the related LdNT2 inosine/guanosine transporter identified the highly conserved Asp389 and Arg393 (equivalent to Asp374 and Arg378 in LdNT1.1) in transmembrane domain 8 as key residues. Among these residues, the mutants in Arg393 (LdNT2) and Arg404 were strongly impaired in trafficking to the plasma membrane, but the other mutants were expressed with high to moderate efficiency at the cell surface, indicating that their mutation impaired transport activity per se. A conservative K153R substitution exhibited a change in substrate specificity, acquiring the ability to transport inosine, a nucleoside that is not a substrate for the wild-type LdNT1.1 permease. These results imply that the Glu94, Lys153, and Asp374 residues may play central roles in the mechanism of substrate translocation in LdNT1.1.

Up-regulation of the high-affinity pyrimidine-preferring nucleoside transporter concentrative nucleoside transporter 1 by tumor necrosis factor-alpha and interleukin-6 in liver parenchymal cells.

BACKGROUND/AIMS: Concentrative nucleoside transporter 1 (CNT1), a high affinity transporter for pyrimidine nucleosides, is responsible for their Na+-dependent concentrative uptake into hepatocytes. Though CNT1 protein amounts increase in rat liver soon after partial hepatectomy, the physiological regulators of CNT1 expression have not yet been identified. METHODS: Rat hepatoma cell lines and hepatocytes isolated from fetuses and adult rats were used to identify single agents able to up-regulate CNT1 expression and activity in liver. TNF-alpha receptor-I (TNFRI) and IL-6 knock-out mice were also used to study CNT1 regulation in vivo. RESULTS: TNF-alpha and IL-6 independently induced CNT1 protein expression in cultured liver parenchymal and FAO hepatoma cells by PI-3 kinase- and ERK-dependent mechanisms, respectively. In vivo data showed that transporter protein levels were low in livers from TNFRI knock-out mice, but not in those from IL-6 deficient animals. However, IL-6 administration only partially restored CNT1 expression in the former model. CONCLUSIONS: This study identifies TNF-alpha as a major in vivo modulator of the nucleoside transporter CNT1 and suggests a secondary role for IL-6 in mediating CNT1 up-regulation by TNF-alpha in vivo. Evidence is provided that two independent pathways are involved in the up-regulation of CNT1 by TNF-alpha and IL-6.

Transmembrane domain 5 of the LdNT1.1 nucleoside transporter is an amphipathic helix that forms part of the nucleoside translocation pathway.

Transporters of the equilibrative nucleoside transporter (ENT) family promote the uptake of nucleosides, nucleobases, and a variety of therapeutic drugs in eukaryotes from protozoa to mammals. Despite its importance, the translocation pathway that mediates the internalization of these substrates has not been identified yet in any of the ENT carriers. Previous genetic studies on the LdNT1.1 nucleoside transporter from Leishmania donovani defined two amino acid residues in predicted transmembrane domains (TMD) 5 and 7 that may line this translocation pathway. The role of TMD5 in forming a portion of the aqueous channel was investigated using the substituted-cysteine accessibility method. A series of 22 cysteine substitution mutants spanning predicted TMD5 were created from a fully functional, cysteine-less, parental LdNT1.1. Cysteine replacement at six positions (M(176)C, T(186)C, S(187)C, Q(190)C, V(193)C, and K(194)C) produced permeases that were inhibited by incubation with sulfhydryl-specific methanethiosulfonate reagents, denoting their solvent accessibility to the translocation pathway. Adenosine was able to block this thiol modification, implying that access to the domain becomes restricted as a consequence of the substrate binding. Strikingly, the Q(190)C substitution interacted differentially with the substrates adenosine and uridine, suggesting that binding of adenosine but not uridine might directly occlude this position. When superimposed on a helical model, all six mutants clustered along one face of the amphipathic alpha-helix predicted for TMD5, strongly suggesting its involvement in the translocation pathway through LdNT1.1.

Índice de masa corporal en embarazadas adolescentes

Se realizó el estudio en 600 gestantes adolescentes atendidas en el Hospital Docente Ginecoobstétrico "Eusebio Hernández", durante el período de julio de 1997 a diciembre de 1999, con el objetivo de conocer la influencia del índice de masa corporal sobre el crecimiento fetal y el peso del niño al nacer. Se les evaluó la edad ginecológica, la ocupación, el estado civil, cultural y nutricional, la altura uterina, y el nivel energético y de nutrimiento de la dieta consumida. Por ultrasonido fetal se midió el peso, el diámetro biparietal y transverso del tórax, la longitud del fémur, y la circunferencia cefálica y abdominal; y al recién nacido, la edad gestacional, la talla y el peso. Se detectaron diferencias estadísticas (p < 0,05) en las dimensiones fetales y el peso del niño al nacer, atendiendo al índice de masa corporal pregestacional. Este estudio mostró la importancia de la utilización de este índice en la atención integral de las embarazadas adolescentes.

A study was performed on 600 pregnant adolescents seen at "Eusebio Hernández" Teaching Gynecological and Obstetric Hospital from July 1997 to December, 1999 to find out the influence of the body mass index over the fetal growth and the birth weight. Their gynecological age, occupation, marital status, cultural and nutritional conditions, uterine height and the energy and nutrient levels of the consumed diet were evaluated. Fetal ultrasound served to measure weight, biparietal diameter, transverse diameter of the thorax, femur length and head and abdominal circumference whereas gestational age, height and weight were evaluated in the newborn. Statistical differences (p < 0,05) were found between fetal dimensions and the birth weight of the newborn according to the pre-gestational body mass index. This study showed the importance of this index in the comprehensive care of pregnant adolescents.

Cell-cycle-dependent regulation of CNT1, a concentrative nucleoside transporter involved in the uptake of cell-cycle-dependent nucleoside-derived anticancer drugs.

Most nucleoside-derived anticancer drugs are taken up by the high-affinity Na-dependent nucleoside transporter CNT1. Since such drugs are to some extent cell-cycle-dependent in their cytotoxic action, we examined the relationship between CNT1 expression and cell-cycle progression in the rat hepatoma cell line FAO. Cell cultures were synchronized either at late G1 or early S stages by combining mimosin treatment with either previous synchronization or not by serum starvation. Cell-cycle progression was then assessed by measuring [methyl-3H]thymidine incorporation into DNA and monitoring cyclin E and A protein levels. In these conditions, CNT1 protein amounts increase at the G1-S transition. When cells were synchronized using hydroxyurea (HU), which directly interacts with nucleotide metabolism by inhibiting ribonucleotide reductase, CNT1 protein amounts increased in synchronized cells and remained high during cell-cycle progression. These data indicate that CNT1 adapts to cell-cycle progression and responds to nucleos(t)ide metabolism status, a feature that might contribute to the cytotoxic action of cell-cycle-dependent anticancer drugs.

Prevalencia de la anemia ferropénica en mujeres embarazadas / Prevalence of iron-deficiency anemia in pregnant women

Con el objetivo de identificar la prevalencia de la anemia por deficiencia de hierro, se estudió en la consulta de nutrición del Hospital Docente Ginecoobstétrico "Eusebio Hernández", desde enero de 1993 a diciembre de 1999 a 11 904 gestantes; de ellas 5 169 eran portadoras de anemia ferropénica. La prevalencia alcanzó el 43,1 porciento y el grupo de edad más vulnerable fue el de 20 a 24 años. Las gestantes con bajo peso preconcepcional y las comprendidas entre las 14 y 23 semanas de gestación fueron las más afectadas. La anemia de mayor prevalencia fue la leve, y representó el 75,8 porciento, mientras que las variables maternas más involucradas fueron: los deficientes hábitos alimentarios, la hiperemesis gravídica y los antecedentes de 3 o más abortos. Este estudio evidenció la magnitud y el grado de severidad de la anemia ferropénica en las gestantes atendidas

Retención de la vitamina C durante el almacenamiento en jugo de naranja enriquecido / Vitamin C retention during storage in enriched orange juice

Se determinó el contenido de vitamina C durante el almacenamiento del jugo de naranja enriquecido. Se halló diferencia significativa al quinto mes de almacenamiento en relación con el contenido inicial de la vitamina; la retención de ésta fue del 76 % a los 5 meses y del 50 % a los 12 meses. La cantidad de vitamina C a los 12 meses representa aún un aporte significativo para la nutrición de los niños