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OBJECTIVES: Transcobalamin II (TC) promotes the cellular uptake of cobalamin (Cbl) through receptor-mediated endocytosis of the TC-cbl complex in peripheral tissues. TC deficiency is a rare disorder that causes intracellular Cbl depletion. It presents in early infancy with a failure to thrive, diarrhea, anemia, agammaglobulinemia, and pancytopenia. Data from five TC-deficient patients including clinical, biochemical, and molecular findings, as well as long-term outcomes, were collected. CASE PRESENTATION: Mutation analysis revealed one unreported pathogenic variant in the TCN2 gene. One patient had exocrine pancreatic insufficiency. We conducted a retrospective analysis of C3 and C3/C2 from dried blood samples, as this is implemented for newborn screening (NBS). We detected a marked increase in the C3/C2 ratio in two samples. Treatment was based on parenteral Cbl. Three patients treated before six months of age had an initial favorable outcome, whereas the two treated later or inadequately had neurological impairment. CONCLUSIONS: This is the first report of Argentinean patients with TC deficiency that detected a new variant in TCN2. NBS may be a tool for the early detection of TC deficiency. This data emphasizes that TC deficiency is a severe disorder that requires early detection and long-term, aggressive therapy. Accurate diagnosis is imperative, because early detection and treatment can be life-saving.

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Glioblastoma is the most aggressive type of brain tumor, with current therapies failing to significantly improve patient survival. Vitamins have important effects on cellular processes that are relevant for tumor development and progression. AIM: The present study explored the effect of pyridoxine or cobalamin supplementation on the viability and cell cycle progression of human glioblastoma cell line U-87 MG. METHOD: Cell cultures were treated with increasing concentrations of pyridoxine or cobalamin for 24-72 h. After supplementation, cell viability and cell cycle progression were assessed by spectrophotometry and flow cytometry. Analysis of Bcl-2 and active caspase 3 expression in supplemented cells was performed by western blot. RESULT: The results show that pyridoxine supplementation decreases cell viability in a dose and time dependent manner. Loss of viability in pyridoxin-supplemented cells is probably related to less cell cycle progression, higher active caspase 3 expression and apoptosis. In addition, Bcl-2 expression did not appear to be altered by vitamin supplementation, but active caspase 3 expression was significantly increased in pyridoxine-, but not cobalamin-supplemented cells, furthermore, cobalamin inhibited the pyridoxine cytotoxicity in the cell viability assay when combined. CONCLUSION: The results suggest that pyridoxine supplementation promotes apoptosis in human glioblastoma-derived cells and may be useful to enhance the effect of cytotoxic therapies in vivo.

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Introduction: Imerslund-Gräsbeck syndrome (IGS) is a rare congenital disorder characterized by decreased vitamin B12, megaloblastic anemia, and proteinuria. Clinical case: A 58-year-old woman with four episodes of generalized tonic movements whose paraclinical findings showed cyanocobalamin deficiency. The presence of gait disturbances and constitutional syndrome was reported upon questioning, which required further investigation. The extension tests confirmed type 1 IGS, so it was decided to continue the cyanocobalamin management and nutrition evaluation, with which an adequate evolution was achieved. The patient was eventually discharged. Conclusion: This pathology is low prevalence and mainly affects the first decade of life. It prefers the female sex and is characterized by a decrease in vitamin B12, which can predispose to other disorders such as ataxia and growth retardation.

Introducción: el síndrome de Imerslund-Gräsbeck es un trastorno congénito infrecuente caracterizado por disminución de la vitamina B12, anemia megaloblástica y proteinuria. Caso clínico: mujer de 58 años de edad con cuatro episodios de movimientos tónicos generalizados cuyos paraclínicos mostraban deficiencia de cianocobalamina, por lo que en el interrogatorio se reportaba la presencia de alteraciones en la marcha y síndrome constitucional que requería ampliar los estudios. Los exámenes de extensión confirmaron el síndrome de Imerslund-Gräsbeck tipo 1, de modo que se decidió continuar el manejo con cianocobalamina y valoración con nutrición, con lo que se obtuvo una adecuada evolución y se decidió dar egreso a la paciente. Conclusión: esta patología tiene una baja prevalencia y afecta principalmente a la primera década de la vida, tiene predilección por el sexo femenino y se caracteriza por una disminución de la vitamina B12, que puede predisponer a otras alteraciones como ataxia y retraso en el crecimiento.

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Millions of dollars have been increasingly spent on plant-based diets. Considering that vitamin B12 is obtained from the consumption of animal-derived foods, new sources of vitamin B12 and methods of food fortification are being eagerly sought. Therefore, this work aims to evaluate advances in situ fermentation processes of food and beverages produced on a large scale and industrial applications for obtaining cobalamin-rich products. Bibliometric analysis was performed and revealed that several studies report a great capacity for in situ biofortification of B12 in foods, mostly on the use of propionic (PB) and lactic (LAB) bacteria. In this context, market potentials for such products, the main microorganisms, including simultaneous cultures, and their respective applications have been presented herein. Although knowledge on potential applications is still limited, field research has been increasingly conducted, thus revealing scientific and technological opportunities, both for the production and the stability of B12 found in plant-based foods.

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Introduction: Megaloblastic anemias secondary to Vitamin B12 deficiency are a group of pathologies produced by defective nuclear DNA synthesis. Objective: To describe the maturation alterations found in hematopoietic precursors of the bone marrow in a series of patients with megaloblastic anemia. Methods: Were included patients attended at the Regional Hospital of Concepción with bone marrow samples sent for the study of cytopenia by flow cytometry whose final diagnosis was megaloblastic anemia. The immunophenotype was performed with CD45, CD34, CD117, HLA-DR, markers of neutrophil (CD13, CD11b, CD10, CD16) and/or erythroblast (CD105, CD71, CD36) maturation. Results: From the flow cytometry laboratory database, 8 patients with megaloblastic anemia were identified, and myelodysplastic syndromes (n=9) and normal or reactive bone marrow (n=10) were used as controls. 44% were men, with a median age of 58 years. Megaloblastic anemia was associated with a higher proportion of size and complexity of erythroid and myeloid progenitors compared to lymphocytes compared to controls. The total percentage of erythroblasts and the proportion of CD34+ myeloid cells associated with erythroid lineage was higher in megaloblastic anemia, associated with a maturation arrest in the CD105+ precursor stage (69% vs 19% and 23%, p<0.001). The heterogeneity of CD36 and CD71 in megaloblastic anemia was similar to myelodysplastic syndromes. Conclusions: Megaloblastic anemia produces a heterogeneous involvement of hematopoiesis, characterized by a greater size and cellular complexity of precursors of the neutrophil and erythroid series and a maturation arrest of the erythroblasts.

Introducción: Anemias megaloblásticas secundarias a la deficiencia de vitamina B12 son patologías producidas por una síntesis defectuosa del ADN nuclear. Objetivo: Describir las alteraciones madurativas encontradas en precursores hematopoyéticos de la médula ósea de una serie de pacientes con anemia megaloblástica. Métodos: Se incluyeron pacientes atendidos en el Hospital Regional de Concepción con muestras de médula ósea enviadas para estudio de citopenias por citometría de flujo cuyo diagnóstico fue anemia megaloblástica. El inmunofenotipo se realizó con CD45, CD34, CD117, HLA-DR, marcadores de maduración de serie de neutrófilo (CD13, CD11b, CD10, CD16) y/o eritroblasto (CD105, CD71, CD36). Resultados: Se identificaron 8 pacientes con anemia megaloblástica y como controles se utilizaron síndromes mielodisplásicos (n=9) y médula ósea normal o reactiva (n=10). El 44% eran hombres, con una mediana de edad de 58 años. La anemia megaloblástica se asoció con una mayor proporción de tamaño y complejidad de progenitores eritroides y mieloides con respecto de los linfocitos en comparación a los controles. El porcentaje total de eritroblastos y la proporción de células mieloides CD34+ comprometidas con el linaje eritroide fue mayor en anemia megaloblástica, asociado a una parada madurativa en la etapa de precursor CD105+ (69% vs 19% y 23%, p <0.001). La heterogeneidad de CD36 y CD71 en anemia megaloblástica fue similar a los síndromes mielodisplásicos. Conclusiones: la anemia megaloblástica produce una afectación heterogénea de la hematopoyesis, caracterizada por un mayor tamaño y complejidad celulares de precursores de la serie neutrófilo y eritroide y una detención madurativa de los eritroblastos.

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Vitamin B12 is a micronutrient required by a variety of organisms for healthy cellular functioning. Despite the systemic effects observed in cases of B12 deficiency, relatively little is known about how vitamin B12 affects immune health, especially in amphibians, which are declining at unprecedented rates. In this study, we tested how supplementing an algae diet with B12 affects the innate and adaptive immunity of Cuban tree frog (Osteopilus septentrionalis) tadpoles. We found that innate immunity, as measured by a bacterial killing assay, was significantly more robust in B12-supplemented tadpoles than control tadpoles, but no significant differences were found in natural antibody production or hematocrit between groups. Adaptive immunity, as measured by Aeromonas hydrophila-specific IgY antibodies, was significantly greater in tadpoles challenged with A. hydrophila and supplemented with B12 than in control tadpoles, those only challenged with A. hydrophila, and those only given B12. Our results suggest that vitamin B12 is an important factor in maintaining a functional immune system in tadpoles, which may also be true for all vertebrates.

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Introduction: Megaloblastic anemias secondary to Vitamin B12 deficiency are a group of pathologies produced by defective nuclear DNA synthesis. Objective: To describe the maturation alterations found in hematopoietic precursors of the bone marrow in a series of patients with megaloblastic anemia. Methods: Were included patients attended at the Regional Hospital of Concepción with bone marrow samples sent for the study of cytopenia by flow cytometry whose final diagnosis was megaloblastic anemia. The immunophenotype was performed with CD45, CD34, CD117, HLA-DR, markers of neutrophil (CD13, CD11b, CD10, CD16) and/or erythroblast (CD105, CD71, CD36) maturation. Results: From the flow cytometry laboratory database, 8 patients with megaloblastic anemia were identified, and myelodysplastic syndromes (n=9) and normal or reactive bone marrow (n=10) were used as controls. 44% were men, with a median age of 58 years. Megaloblastic anemia was associated with a higher proportion of size and complexity of erythroid and myeloid progenitors compared to lymphocytes compared to controls. The total percentage of erythroblasts and the proportion of CD34+ myeloid cells associated with erythroid lineage was higher in megaloblastic anemia, associated with a maturation arrest in the CD105+ precursor stage (69% vs 19% and 23%, p<0.001). The heterogeneity of CD36 and CD71 in megaloblastic anemia was similar to myelodysplastic syndromes. Conclusions: Megaloblastic anemia produces a heterogeneous involvement of hematopoiesis, characterized by a greater size and cellular complexity of precursors of the neutrophil and erythroid series and a maturation arrest of the erythroblasts.

Introducción: Anemias megaloblásticas secundarias a la deficiencia de vitamina B12 son patologías producidas por una síntesis defectuosa del ADN nuclear. Objetivo: Describir las alteraciones madurativas encontradas en precursores hematopoyéticos de la médula ósea de una serie de pacientes con anemia megaloblástica. Métodos: Se incluyeron pacientes atendidos en el Hospital Regional de Concepción con muestras de médula ósea enviadas para estudio de citopenias por citometría de flujo cuyo diagnóstico fue anemia megaloblástica. El inmunofenotipo se realizó con CD45, CD34, CD117, HLA-DR, marcadores de maduración de serie de neutrófilo (CD13, CD11b, CD10, CD16) y/o eritroblasto (CD105, CD71, CD36). Resultados: Se identificaron 8 pacientes con anemia megaloblástica y como controles se utilizaron síndromes mielodisplásicos (n=9) y médula ósea normal o reactiva (n=10). El 44% eran hombres, con una mediana de edad de 58 años. La anemia megaloblástica se asoció con una mayor proporción de tamaño y complejidad de progenitores eritroides y mieloides con respecto de los linfocitos en comparación a los controles. El porcentaje total de eritroblastos y la proporción de células mieloides CD34+ comprometidas con el linaje eritroide fue mayor en anemia megaloblástica, asociado a una parada madurativa en la etapa de precursor CD105+ (69% vs 19% y 23%, p <0.001). La heterogeneidad de CD36 y CD71 en anemia megaloblástica fue similar a los síndromes mielodisplásicos. Conclusiones: la anemia megaloblástica produce una afectación heterogénea de la hematopoyesis, caracterizada por un mayor tamaño y complejidad celulares de precursores de la serie neutrófilo y eritroide y una detención madurativa de los eritroblastos.

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BACKGROUND: Vitamin B12 and folate are key nutrients that help children reach their full potential in growth and development; however, little is known about the status of these vitamins in Brazilian children. OBJECTIVES: To describe the serum concentrations of vitamin B12 and folate, to investigate the association between high folate concentration (HFC) and vitamin B12 deficiency, and to evaluate the association between vitamin B12 and stunting/underweight in Brazilian children aged 6-59 mo. METHODS: Data from 7417 children aged 6-59 mo collected during the Brazilian National Survey on Child Nutrition were used. Serum concentrations of vitamin B12 of <150 pmol/L and folate of <10 nmol/L were classified as deficient, and folate concentrations of >45.3 nmol/L were classified as HFC. Children with length/height-for-age z-score of less than -2 were considered stunted, and those with weight-for-age z-score of less than -2 were underweight. Logistic regression models were performed. RESULTS: In Brazil, 14.2% (95% CI: 12.2, 16.1) of children aged 6-59 mo had vitamin B12 deficiency, 1.1% (95% CI: 0.5, 1.6) had folate deficiency, and 36.9% (95% CI: 33.4, 40.3) had HFC. Vitamin B12 deficiency was higher in children from the northern region of Brazil (28.5%), between 6 and 24 mo (25.3%), whose mothers had lower formal education (0-7 y; 18.7%). Children with HFC had 62% lower odds (OR: 0.38; 95% CI: 0.27, 0.54) of vitamin B12 deficiency than those with normal/deficient folate. Children with vitamin B12 deficiency and normal/deficient folate had higher odds of stunting (OR: 1.58; 95% CI: 1.02, 2.43) than children without vitamin B12 deficiency and normal/deficient folate. CONCLUSIONS: Vitamin B12 deficiency is a public health problem among Brazilian children aged <2 y with vulnerable socioeconomic status. HFC was inversely associated with vitamin B12 deficiency, and lower odds of stunting were observed in children with HFC and vitamin B12 deficiency than in those with vitamin B12 deficiency and normal/deficient folate.

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BACKGROUND: Vitamins B6, B12, and folate are essential for the formation and maintenance of the human brain, but studies evaluating these vitamins with early childhood development (ECD) in children under 5 y are limited and controversial. OBJECTIVES: To evaluate the association between vitamins B6, B12, and folate concentrations/status and ECD. METHODS: Data regarding 6520 children aged 6-59 mo from the ENANI-2019 (the Brazilian National Survey on Child Nutrition) were analyzed. ECD was assessed using the Survey of Well-being of Young Children's milestones questionnaire. Vitamin B6 concentration (nmol/L) was classified according to the tertile of the distribution and with the cutoff <20 nmol/L. Folate concentrations >45.3 nmol/L were classified as high, and vitamin B12 <150 pmol/L was deficient. The graded response model was used to estimate developmental age, and the developmental quotient (DQ) was calculated as the developmental age divided by chronological age. Multiple linear regression models were adjusted for confounders. RESULTS: The DQ mean (95% confidence interval) for Brazilian children was 0.99 (0.97-1.01). Children aged 6-23 mo [1.13 (1.10-1.16)] had a higher DQ mean than those aged 24-35 [0.99 (0.95-1.03)] and 36-59 mo [0.89 (0.86-0.92)]. Child age was inversely associated with DQ (ß = -0.007; P < 0.001). An interaction between child age and vitamin B12 deficiency in the DQ (ß = -0.005; P < 0.001) indicated that, in children aged 36-59 mo, the DQ was markedly lower in children with vitamin B12 deficiency than in those without vitamin B12 deficiency. Vitamin B6 concentrations were directly associated with the DQ (ß = 0.0004; P = 0.031) among children aged 24-59 mo in the adjusted model. No association was observed between folate status and DQ. CONCLUSIONS: In Brazil, the DQ is lower among older children and those with vitamin B12 deficiency. Vitamin B6 status was directly associated with the DQ in children aged 24-59 mo.

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Interest in plant-based diets and vegetarianism is increasing worldwide, however, a concern for total vegetarians is vitamin B12 (B12) deficiency. We conducted a systematic review to investigate non-animal food sources of B12. Databases were PubMed, LILACS, Cochrane, Embase and Google Scholar, up to September 9, 2020. Quality of the eligible studies were assessed. We identified 25 studies which assessed B12 content in seaweeds, mushrooms, plants and fermented foods. Initial studies were microbiological bioassay, ELISA and HPLC. In the last decade, more sensitive method for real B12 determination was used, the liquid chromatography-electrospray ionization tandem mass spectrometry chromatograms. Real B12 content varied from mean (SD) mcg/portion size of seaweed hijiki 3 × 10-3/7 g to nori 1.03 - 2.68/sheet; mushroom white button cap 2 × 10-3(7 × 10-4)/20 g dry weight (dw) to shiitake 0.79(0.67)-1.12 (0.78)/20 g dw; and fermented foods from soy yogurt 20/cup. It is possible that daily recommendations for B12 can be met by a varied diet containing non-animal B12 food sources. Future research should consider different methods of storage, preparation, fermented foods and standardization of the production of certain foods.Supplemental data for this article is available online at https://doi.org/10.1080/10408398.2022.2053057.

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A glassy carbon electrode was modified with nitrogen and sulfur co-doped graphene quantum dots immobilized in chitosan for the monitoring of multivitamins. The graphene quantum dots were synthesized using a simple citric acid/l-cysteine pyrolysis procedure. The co-doping with nitrogen and sulfur in the graphene matrix was confirmed by spectroscopic techniques. Electron microscopy results showed that the synthesized quantum dots had a diameter of 3.4 ± 1.4 nm. Electrochemical techniques showed excellent current responses to vitamin oxidation provided by the modified electrode compared to the bare electrode. The parameters of square wave voltammetry were optimized in order to obtain the best current responses and to study the electrochemical oxidation of vitamins. The calibration plots for vitamins B2, B6 and B12 were constructed in 0.1 mol L-1 sodium acetate buffer (pH 5.0) with limits of detection of 0.30, 30.1 and 0.32 nmol L-1, respectively. Lastly, the modified electrode was effectively implemented in the quantification of vitamins in classic and fruit-based energy drink samples.

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Vitamin B12 is an essential micronutrient for cell growth and the development of the central nervous system. Its deficiency can manifest clinically as megaloblastic anemia, peripheral neuropathy, myelopathy and neuropsychiatric disorders. Early detection and treatment are essential as it can cause irreversible neurological sequelae. Diagnosis is often challenging as it is based on clinical and biochemical features. Clinically, the symptoms are nonspecific and equivocal. Biochemically, there is no gold standard to detect Cobalamin deficiency. The available biomarkers do not have a defined cut-off value or are not sensitive or specific enough. This article exposes the different causes of vitamin B12 deficiency, analyzes the advantages and disadvantages of biochemical markers and, for the first time, proposes an algorithmic diagnosis using biomarkers and therapeutic tests. The ultimate goal is to alert pediatricians to the difficulties of diagnosing vitamin B12 deficiency and strategies are proposed to differentiate between acquired and congenital cobalamin conditions. Finally, the treatment according to the etiology is described in a practical manner, as well as the expected time for improvement of the biochemical parameters.

La vitamina B12 es un micronutriente fundamental para el crecimiento celular y el desarrollo del sistema nervioso central. Su deficiencia puede manifestarse clínicamente como anemia megaloblástica, neuropatía periférica, mielopatía y trastornos neuropsiquiátricos. La detección y el tratamiento tempranos son esenciales, ya que esta deficiencia puede generar secuelas neurológicas irreversibles. El diagnóstico suele ser un desafío, ya que se basa en pilares clínicos y bioquímicos. Clínicamente, los síntomas son inespecíficos y equívocos. Bioquímicamente no existe un gold standard para diagnosticar la deficiencia de cobalamina. Los biomarcadores existentes no presentan un valor de corte definido o no son lo suficientemente sensibles o específicos. Este trabajo expone las diferentes causas de deficiencia de vitamina B12, analiza las ventajas y desventajas de los marcadores bioquímicos y por primera vez se plantea un algoritmo diagnóstico mediante biomarcadores y pruebas terapéuticas. El objetivo último es alertar a los pediatras acerca las dificultades que representa el diagnóstico de deficiencia de vitamina B12 y se proponen estrategias para diferenciar cuadros adquiridos versus congénitos de la deficiencia de cobalamina. Por último, se describe de manera práctica el tratamiento según la etiología así como el tiempo esperado para la mejoría de los parámetros bioquímicos.

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Resumen Introducción: el Síndrome de Imerslund-Gränsbeck es un trastorno congénito inusual que cursa con disminución de la Vitamina B12, anemia megaloblástica y proteinuria sin afección renal que cual se produce por una mutación de los cromosomas 10 y 14, que condicionan un defecto en el receptor del complejo vitamina B12-factor intrínseco del enterocito ileal. Fue descrita por Olga Imerslund y Armas Gransbeck. Objetivo: caracterizar a la población que ha padecido el Síndrome de Imerslund-Gränsbeck. Metodología: revisión sistemática de la literatura de casos clínicos. Resultados: se incluyeron 68 casos, en la mayoría de los casos el diagnostico en los primeros 10 años de vida, en el que se evidenció una mayor frecuencia en mujeres, y se encontró asociado con antecedentes familiares como consanguinidad entre padres (14,6%). La manifestación más frecuente fue palidez (20,9%), seguido de vomito (10,5%) y anorexia (9,8%). La anemia megaloblástica (66,2%) fue el hallazgo más frecuente y el tratamiento se dio con cianocobalamina (intramuscular u oral) para regular las concentraciones plasmáticas de esta vitamina. Conclusión: el Síndrome de Imerslund Gränsbeck tiene una baja prevalencia y se presenta con mayor frecuencia en el continente europeo, tiene predilección por el sexo femenino y se caracteriza por una disminución de la vitamina B12 que pueden que puede predisponer a otras alteraciones como ataxia y retraso en el crecimiento.

Abstract Introduction: Imerslund-Gränsbeck Syndrome is an unusual congenital disorder that causes a decrease in vitamin B12, megaloblastic anemia and proteinuria without kidney involvement that is caused by a mutation of chromosomes 10 and 14, which determine a defect in the complex receptor vitamin B12-ileal enterocyte intrinsic factor. It was described by Olga Imerslund and Armas Gransbeck. Objective: to characterize the population that has suffered from Imerslund Gränsbeck syndrome. Methodology: systematic review of the clinical case literature. Results: 68 cases were included, in most cases the diagnosis in the first 10 years of life, in which a higher frequency was found in women, and was found to be associated with family history such as consanguinity between parents (14.6%). The most frequent manifestation was paleness (20.9%), followed by vomiting (10.5%) and anorexia (9.8%). Megaloblastic anemia (66.2%) was the most frequent finding and treatment was given with cyanocobalamin (intramuscular or oral) to regulate plasma concentrations of this vitamin. Conclusion: Imerslund-Gränsbeck Syndrome has a low prevalence and occurs more frequently in the European continent, has a predilection for females and is characterized by a decrease in vitamin B12 that may predispose to other disorders such as ataxia and retardation in growth.

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BACKGROUND: Listeria monocytogenes is a foodborne pathogen that causes listeriosis in humans. This pathogen activates multiple regulatory mechanisms in response to stress, and cobalamin biosynthesis might have a potential role in bacterial protection. Low temperature is a strategy used in the food industry to control bacteria proliferation; however, L. monocytogenes can grow in cold temperatures and overcome different stress conditions. In this study we selected L. monocytogenes List2-2, a strain with high tolerance to the combination of low temperature + copper, to understand whether the cobalamin biosynthesis pathway is part of the tolerance mechanism to this stress condition. For this, we characterized the transcription level of three cobalamin biosynthesis-related genes (cbiP, cbiB, and cysG) and the eutV gene, a transcriptional regulator encoding gene involved in ethanolamine metabolism, in L. monocytogenes strain List2-2 growing simultaneously under two environmental stressors: low temperature (8 °C) + copper (0.5 mM of CuSO4 × 5H2O). In addition, the gene cbiP, which encodes an essential cobyric acid synthase required in the cobalamin pathway, was deleted by homologous recombination to evaluate the impact of this gene in L. monocytogenes tolerance to a low temperature (8 °C) + different copper concentrations. RESULTS: By analyzing the KEGG pathway database, twenty-two genes were involved in the cobalamin biosynthesis pathway in L. monocytogenes List2-2. The expression of genes cbiP, cbiB, and cysG, and eutV increased 6 h after the exposure to low temperature + copper. The cobalamin cbiP mutant strain List2-2ΔcbiP showed less tolerance to low temperature + copper (3 mM) than the wild-type L. monocytogenes List2-2. The addition of cyanocobalamin (5 nM) to the medium reverted the phenotype observed in List2-2ΔcbiP. CONCLUSION: These results indicate that cobalamin biosynthesis is necessary for L. monocytogenes growth under stress and that the cbiP gene may play a role in the survival and growth of L. monocytogenes List2-2 at low temperature + copper.

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This comprehensive review establishes the role of vitamin B12 as adjunct therapy for viral infections in the treatment and persistent symptoms of COVID-19, focusing on symptoms related to the muscle-gut-brain axis. Vitamin B12 can help balance immune responses to better fight viral infections. Furthermore, data from randomized clinical trials and meta-analysis indicate that vitamin B12 in the forms of methylcobalamin and cyanocobalamin may increase serum vitamin B12 levels, and resulted in decreased serum methylmalonic acid and homocysteine concentrations, and decreased pain intensity, memory loss, and impaired concentration. Among studies, there is much variation in vitamin B12 doses, chemical forms, supplementation time, and administration routes. Larger randomized clinical trials of vitamin B12 supplementation and analysis of markers such as total vitamin B12, holotranscobalamin, total homocysteine and methylmalonic acid, total folic acid, and, if possible, polymorphisms and methylation of genes need to be conducted with people with and without COVID-19 or who have had COVID-19 to facilitate the proper vitamin B12 form to be administered in individual treatment.

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BACKGROUND: Listeria monocytogenes is a foodborne pathogen that causes listeriosis in humans. This pathogen activates multiple regulatory mechanisms in response to stress, and cobalamin biosynthesis might have a potential role in bacterial protection. Low temperature is a strategy used in the food industry to control bacteria proliferation; however, L. monocytogenes can grow in cold temperatures and overcome different stress conditions. In this study we selected L. monocytogenes List2-2, a strain with high tolerance to the combination of low temperature +copper, to understand whether the cobalamin biosynthesis pathway is part of the tolerance mechanism to this stress condition. For this, we characterized the transcription level of three cobalamin biosynthesis related genes ( cbiP , cbiB, and cysG ) and the eutV gene, a transcriptional regulator encoding gene involved in ethanolamine metabolism, in L. monocytogenes strain List2-2 growing simultaneously under two environmental stressors: low temperature (8 °C) +copper (0.5 mM of CuSO4 ×5H2O). In addition, the gene cbiP , which encodes an essential cobyric acid synthase required in the cobalamin pathway, was deleted by homologous recombination to evaluate the impact of this gene in L. monocytogenes tolerance to a low temperature (8 °C) +different copper concentrations. RESULTS: By analyzing the KEGG pathway database, twenty-two genes were involved in the cobalamin biosynthesis pathway in L. monocytogenes List2-2. The expression of genes cbiP , cbiB, and cysG, and eutV increased 6 h after the exposure to low temperature +copper. The cobalamin cbiP mutant strain List2-2Δ cbiP showed less tolerance to low temperature +copper (3 mM) than the wild type L. monocytogenes List2-2. The addition of cyanocobalamin (5 nM) to the medium reverted the phenotype observed in List2-2Δ cbiP . CONCLUSION: These results indicate that cobalamin biosynthesis is necessary for L. monocytogenes growth under stress and that the cbiP gene may play a role in the survival and growth of L. monocytogenes List2-2 at low temperature +copper.

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OBJECTIVE: To evaluate the clinical outcomes at age 1.5 ± 0.5 years of infants with vitamin B12 deficiency identified by newborn screening (NBS). STUDY DESIGN: Prospective multicenter observational study on health outcomes of 31 infants with vitamin B12 deficiency identified by NBS. Neurodevelopment was assessed by the Denver Developmental Screening Test. RESULTS: In 285 862 newborns screened between 2016 and 2019, the estimated birth prevalence of vitamin B12 deficiency was 26 in 100 000 newborns, with high seasonal variations (lowest in summer: 8 in 100 000). Infants participating in the outcome study (N = 31) were supplemented with vitamin B12 for a median (range) of 5.9 (1.1-16.2) months. All achieved age-appropriate test results in Denver Developmental Screening Test at age 15 (11-23) months and did not present with symptoms characteristic for vitamin B12 deficiency. Most (81%, n = 25) mothers of affected newborns had a hitherto undiagnosed (functional) vitamin B12 deficiency, and, subsequently, received specific therapy. CONCLUSIONS: Neonatal vitamin B12 deficiency can be screened by NBS, preventing the manifestation of irreversible neurologic symptoms and the recurrence of vitamin B12 deficiency in future pregnancies through adequate treatment of affected newborns and their mothers. The high frequency of mothers with migrant background having a newborn with vitamin B12 deficiency highlights the need for improved prenatal care.

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Abstract Trichinellosis is a zoonosis results from eating raw or semi-cooked meat of infected animals. Medicinal plants have been used lately as alternatives and/or combined therapies to resolve some drawbacks of the current regimens. This work analyzed the effect of albendazole monotherapy on Trichinella spiralis experimental infection (group A), in comparison to P. granatum and amygdalin extracts +cobalamin (group B), plus its combination with albendazole (group C). The study revealed that the extracts alone or combined with albendazole had an inferior effect to albendazole monotherapy regarding number of adult worms (40.83 ±3.82, 18.67 ±1.86 and 16.83 ±2.32, respectively). However, their effect was more obvious in muscle phase combined with albendazole, achieving the lower number of larvae/mL tissue homogenate (22.33 ±3.27 in comparison to 39.67 ±2.58 achieved by albendazole monotherapy). The extracts exerted a significant immunomodulatory effect by reducing the local CD4+ expression in the intestine as well as in muscle phase (1.15 ±0.25 and 3.80 ±0.65 in comparison to 4.97 ±0.37 and 12.20 ±0.87 with albendazole monotherapy, respectively). So, these extracts improved the therapeutic efficacy of albendazole, specifically in muscle phase and counteracted the inflammatory reaction caused by albendazole monotherapy, thus extensively alleviating the resulting myositis.

Resumo Trichinellosis é uma zoonose resultante da ingestão de carne crua ou semicozida de animais infectados. As plantas medicinais têm sido usadas, ultimamente, como alternativas e/ou terapias combinadas, para resolver algumas desvantagens dos regimes atuais. Este trabalho analisou o efeito da monoterapia albendazole na infecção experimental por Trichinella spiralis (grupo A), em comparação com extratos de P. granatum e amígdalina +cobalamina (grupo B), além de sua combinação com albendazol (grupo C). O estudo revelou que os extratos sozinho ou combinado com albendazol teve efeito inferior à monoterapia albendazol em relação ao número de vermes adultos (40,83 ±3,82, 18,67 ±1,86 e 16,83 ±2,32, respectivamente). No entanto, seu efeito foi mais óbvio na fase muscular combinado com o albendazol, alcançando o menor número de larvas/mL homogeneizado de tecido (22,33 ±3,27 em comparação com 39,67 ±2,58 obtidos pela monoterapia albendazol). Os extratos exerceram um efeito imunomodulatório significativo, ao reduzir a expressão local CD4+ no intestino, bem como na fase muscular (1,15 ±0,25 e 3,80 ±0,65 em comparação com 4,97 ±0,37 e 12,20 ±0,87 com monoterapia albendazol, respectivamente). Assim, esses extratos melhoraram a eficácia terapêutica do albendazol, especificamente na fase muscular e neutralizaram a reação inflamatória causada pela monoterapia albendazol, aliviando extensivamente a miosite resultante.

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The neurotropic B vitamins B1 (thiamine), B6 (pyridoxine), and B12 (cobalamin) are essential for proper functioning of the nervous system. Deficiencies may induce neurological disorders like peripheral neuropathy (PN) and mainly occur in vulnerable populations (eg, elderly, diabetics, alcoholics). As epidemiologic cohort studies raised safety concerns about vitamin B6/B12 intake being potentially associated with increased risks of hip fracture (HF) and lung cancer (LC), we explored these aspects and performed comprehensive literature searches. However, we suggest not to neglect actual high-risk factors (eg, smoking in LC, higher age in HF) by focusing on individual nutrients, but to examine the complex interaction of numerous factors involved in disease development. Because it warrants continued consideration, we also provide an update on neurotoxicity associated with vitamin B6. We consider that neurological side effects due to vitamin B6 intake are rare and only occur with high daily doses and/or longer treatment duration. The benefit-risk ratio of high-dose treatment with neurotropic B vitamins in indications like PN is therefore considered advantageous, particularly if dosing recommendations are followed and serum levels monitored.

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Intensive use of the chlorinated pesticide chlordecone from the 1970s to 1993 to prevent crop damage in banana plantations of Guadeloupe and Martinique led to diffuse pollution of soils and surface waters, affecting both fauna and human beings in the contaminated areas. Since 2001, drinking water production plants have been equipped with filters containing activated carbon that must be treated after saturation. The objective of this work is to produce a hybrid material composed of activated carbon and vitamin B12 (VB12) for the degradation of chlordecone (CLD). The preparation of such a hybrid material is carried out by non-covalent fixation to achieve an eco-friendly solution for the serious environmental problem of contamination by chlorinated pesticides. It is thus proposed to degrade CLD by a physico-chemical treatment allowing salvage of the catalyst, which is adsorbed on the carbon surface to generate less waste that is inexpedient to treat. Activated carbon (AC) is produced locally from available sugarcane bagasse subjected to phosphoric acid activation. The main characteristics of this material are a major mesoporous structure (0.91%) and a specific (BET) surface area ranging from 1000 to 1500 m2 g-1. The experimental results showed that BagP1.5 has a high adsorption capacity for VB12 due to its large surface area (1403 m2 g-1). The binding of VB12 to the bagasse-derived AC is favoured at high temperatures. The adsorption is optimal at a pH of approximately 6. The maximum adsorption capacity of VB12 on the AC, deduced from the Langmuir model, was 306 mg g-1, confirming the high affinity between the two components. The hybrid material was characterised by FTIR, Raman, X-ray fluorescence spectroscopy and SEM analysis. CLD removal by this hybrid material was faster than that by VB12 or BagP1.5 alone. The CLD degradation products were characterised by mass spectrometry.

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