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1.
BMC Med ; 22(1): 330, 2024 Aug 13.
Article de Anglais | MEDLINE | ID: mdl-39134986

RÉSUMÉ

BACKGROUND: Data have shown that vitamin B12 has immunomodulatory effects via different pathways, which could influence the pathophysiology of sepsis. The objective of this study was to investigate whether vitamin B12 levels, assessed by the measurement of holotranscobalamin (HTC), total vitamin B12 (B12), and methylmalonic acid (MMA, which accumulates in case of B12 deficiency), are associated with the development of sepsis in patients with onset of bacterial infection. METHODS: This was a single-center, prospective observational pilot study. Adult patients who presented to the emergency department with bacterial infection confirmed by a positive microbiological culture result were included in the study and followed up for 6 days to assess whether they developed sepsis or not. The primary objective was to compare HTC concentration in patients who developed sepsis to those who did not develop sepsis. Secondary objectives were the evaluation of B12 and MMA concentrations in those two groups. Multiple logistic regression models were used, with presence of sepsis as the outcome variable, and HTC, B12, and MMA concentrations as predictor variables, separately, and adjusted for potential confounders. RESULTS: From 2019 to 2022, 2131 patients were assessed for eligibility, of whom 100 met the inclusion criteria. One patient was excluded from the analysis due to missing data. Of the 99 patients, 29 developed sepsis. There was no evidence for an association between HTC or B12 concentration and the development of sepsis (OR 0.65, 95% CI 0.31-1.29, p = 0.232, OR 0.84, 95% CI 0.44-1.54, p = 0.584, respectively). There was an association between MMA concentration and the development of sepsis, with a positive effect, i.e. with increasing MMA, the odds for sepsis increased (OR 2.36, 95% CI 1.21-4.87, p = 0.014). This association remained significant when adjusted for confounders (OR 2.72, 95% CI 1.23-6.60, p = 0.018). CONCLUSIONS: Our study found an association between elevated MMA concentration and the development of sepsis. We did not find an association between HTC and B12 concentrations and the development of sepsis. Further, larger studies are warranted, as it could lead to interventional trials investigating whether B12 supplementation provides a clinical benefit to patients with infection or sepsis. TRIAL REGISTRATION: The study was registered on ClinicalTrials.gov under the identifier NCT04008446 on June 17, 2019.


Sujet(s)
Infections bactériennes , Sepsie , Vitamine B12 , Humains , Études prospectives , Mâle , Femelle , Vitamine B12/sang , Adulte d'âge moyen , Sujet âgé , Projets pilotes , Acide méthyl-malonique/sang , Adulte , Transcobalamines/analyse , Sujet âgé de 80 ans ou plus
2.
Birth Defects Res ; 116(8): e2390, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39162364

RÉSUMÉ

BACKGROUND: Folate and vitamin B12 deficiencies in pregnant women are associated with increased risk for adverse maternal and infant health outcomes, including neural tube defects (NTDs). METHODS: A population-based cross-sectional survey was conducted in two rural areas in Ambala District, Haryana, India in 2017 to assess baseline folate and vitamin B12 status among women of reproductive age (WRA) and predict the prevalence of NTDs. We calculated the prevalence of folate and vitamin B12 deficiency and insufficiency by demographic characteristics among 775 non-pregnant, non-lactating WRA (18-49 years). Using red blood cell (RBC) folate distributions and an established Bayesian model, we predicted NTD prevalence. All analyses were conducted using SAS-callable SUDAAN Version 11.0.4 to account for complex survey design. RESULTS: Among WRA, 10.1% (95% CI: 7.9, 12.7) and 9.3% (95% CI: 7.4, 11.6) had serum (<7 nmol/L) and RBC folate (<305 nmol/L) deficiency, respectively. The prevalence of RBC folate insufficiency (<748 nmol/L) was 78.3% (95% CI: 75.0, 81.3) and the predicted NTD prevalence was 21.0 (95% uncertainly interval: 16.9, 25.9) per 10,000 live births. Prevalences of vitamin B12 deficiency (<200 pg/mL) and marginal deficiency (≥200 pg/mL and ≤300 pg/mL) were 57.7% (95% CI: 53.9, 61.4) and 23.5% (95% CI: 20.4, 26.9), respectively. CONCLUSIONS: The magnitude of folate insufficiency and vitamin B12 deficiency in this Northern Indian population is a substantial public health concern. The findings from the survey help establish the baseline against which results from future post-fortification surveys can be compared.


Sujet(s)
Carence en acide folique , Acide folique , Anomalies du tube neural , Population rurale , Carence en vitamine B12 , Vitamine B12 , Humains , Femelle , Anomalies du tube neural/épidémiologie , Anomalies du tube neural/étiologie , Inde/épidémiologie , Adulte , Acide folique/sang , Vitamine B12/sang , Prévalence , Études transversales , Grossesse , Carence en vitamine B12/épidémiologie , Carence en acide folique/épidémiologie , Carence en acide folique/sang , Adolescent , Jeune adulte , Adulte d'âge moyen , Théorème de Bayes
3.
J Assoc Physicians India ; 72(8): 30-35, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39163059

RÉSUMÉ

BACKGROUND: Cyanocobalamin or B12 deficiency is common in the Indian population, and responsible for anemia. Various clinical manifestations include central nervous system and cardiovascular manifestations, secondary to a rise in serum homocysteine levels. METHOD AND PATIENTS: In a routine outpatient department at Bawaskar Hospital and Clinical Research Centre, Mahad, patients with suspected clinical signs and symptoms suggestive of cyanocobalamin deficiency were studied in detail regarding their dietary habits, serum hemoglobin, B12, and homocysteine levels. FINDINGS: A total of 1,992 (female 1,009, 50.75%) were clinically examined in detail. Of these, 945 (49.94%), 999 (50.17%), and 48 (2.40%) were strict vegetarians, both vegetarian and nonvegetarian, and strict nonvegetarians, respectively. Common occupations associated with B12 deficiency include 666 (33.4%) housewives, 396 (19.9%) service workers, 316 (15.9%) businesspeople, 180 (9%), and 198 (9.9%) retired and industrial populations, respectively. Clinical manifestations include recurrent scalp hair loss in 268 (13.5%), poor memory in 240 (12%), tingling and numbness in 200 (10%), and generalized weakness in 387 (19.4%) patients. Additionally, 541 (27.15%) patients had pigmentation of the nail bed, knuckles, oral mucosa, and tongue, while 237 (10.81%) suffered from hypertension and ischemic heart disease. During the process of preparation of vegetarian and nonvegetarian food, there is a 30-48% reduction in vitamin content. Supplementation of vitamin by adding table salt to food on a plate at the time of eating improves the vitamin level in the blood. CONCLUSION: In the absence of laboratory investigations in rural settings, clinical signs and symptoms are helpful in detecting B12 deficiency. Directly adding vitamin powder, similar to table salt, to cooked food on the plate improved blood vitamin levels.


Sujet(s)
Compléments alimentaires , Carence en vitamine B12 , Vitamine B12 , Humains , Carence en vitamine B12/diagnostic , Carence en vitamine B12/épidémiologie , Inde/épidémiologie , Femelle , Mâle , Vitamine B12/sang , Vitamine B12/administration et posologie , Adulte , Population rurale , Adulte d'âge moyen , Homocystéine/sang , Hémoglobines/analyse , Jeune adulte , Régime végétarien/effets indésirables
4.
F1000Res ; 13: 530, 2024.
Article de Anglais | MEDLINE | ID: mdl-39104822

RÉSUMÉ

Background: Malnourished pregnant women are at increased risk of micronutrient deficiency. We assessed the vitamin B12 status in both malnourished and normally nourished pregnant women and their neonates. Additionally, we studied the association between maternal B12 levels, cord B12 levels and neonatal anthropometry. Methods: This cross-sectional study enrolled 63 malnourished and 63 normally nourished mothers and neonates. Maternal and cord blood samples were collected at the time of delivery for estimation of vitamin B12 levels. Maternal and cord vitamin B12 levels were compared using the Mann-Whitney U test. Neonatal anthropometry was correlated with maternal and cord B12 levels using Spearman's correlation. Data were analyzed using SPSS version 25. Results: Mean maternal age was 26.58 yrs. The median cord B12 levels were lower than the maternal B12 levels. Maternal B12 levels showed a strong positive correlation with cord B12 levels (rho = 0.879; p < 0.001). Maternal (p < 0.001) and cord (p < 0.001) vitamin B12 levels were significantly lower in the malnourished group than in the normally nourished group. In malnourished group, 66.8% mothers and 95.2% neonates were Vitamin B12 deficient, whereas 1.5% mothers and 4.7% neonates were vitamin B12 deficient in normally nourished group. In the malnourished group, maternal B12 levels were positively correlated with birth weight (rho 0.363, p = 0.003) and length (rho 0.330, p =0.008), whereas cord B12 levels were positively correlated with birth weight in the normally nourished group. (rho 0.277 p= 0.028). Conclusion: High rates of vitamin B12 deficiency were observed in malnourished mothers and neonates. There was a positive correlation between birth weight, length, and maternal vitamin B12 levels in malnourished mothers. These findings emphasize the need to address maternal malnutrition and vitamin B12 deficiency to improve neonatal health.


Sujet(s)
Anthropométrie , Sang foetal , Malnutrition , Vitamine B12 , Humains , Femelle , Vitamine B12/sang , Nouveau-né , Adulte , Inde , Sang foetal/métabolisme , Sang foetal/composition chimique , Grossesse , Malnutrition/sang , Malnutrition/complications , Études transversales , Carence en vitamine B12/sang , Jeune adulte , Mâle , Mères
5.
Luminescence ; 39(8): e4863, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39143585

RÉSUMÉ

In this study, a bis-indole compound was synthesized, characterized by 1H NMR, Fourier transform infrared, and mass spectroscopic measurements and used as a selective and efficient probe for the spectrofluorimetric analysis of Co (II). The cobalt-induced quenching in the emission maximum at 567 nm was considered as the analytical signal in calibration studies. When encapsulated in a polymethyl methacrylate (PMMA) matrix, the bis-indole compound exhibited a limit of detection (LOD) of 3.60 × 10-11 M for Co (II). Vitamin B12, which contains a cobalt ion in the center of a corrin ring in its structure, was also successfully quantified using the same probe. The bis-indole compound showed a linear response based on quenching for increasing concentrations of vitamin B12, partially mimicking the contracted tetrapyrrole ring found naturally in the center of vitamin B12. The LOD for vitamin B12 was found to be 76 nm. Promising photophysical properties of the proposed probe, including high molar extinction coefficient, considerable quantum yield (0.46 and 0.64 in tetrahydrofuran and PMMA, respectively), high Stoke's shift and satisfactory photostability, make it a good choice for fluorescence-based Co (II) determination. The ML3-type stoichiometry of the complex between the dye and cobalt was elucidated both by Job's method and by high-resolution mass spectrometry (HR-MS).


Sujet(s)
Cobalt , Indoles , Spectrométrie de fluorescence , Vitamine B12 , Cobalt/composition chimique , Vitamine B12/analyse , Vitamine B12/composition chimique , Indoles/composition chimique , Structure moléculaire , Colorants fluorescents/composition chimique , Colorants fluorescents/synthèse chimique , Limite de détection
6.
Medicine (Baltimore) ; 103(32): e39101, 2024 Aug 09.
Article de Anglais | MEDLINE | ID: mdl-39121310

RÉSUMÉ

A disturbance in the metabolism of homocysteine in both the mother and the fetus has been implicated in several placental vasculopathy-related disorders, including pregnancy loss. This study aimed to provide insights into the potential role of homocysteine, Vitamin B12, and folic acid in early pregnancy losses, with a specific focus on the Turkish population. The results of 93 pregnant women who experienced miscarriage between 5 and 14 gestational weeks and 93 healthy pregnant women at the same gestational weeks were compared. The demographic and pregnancy characteristics of all pregnant women were recorded. Vitamin B12, folic acid, and homocysteine levels were measured in serum samples obtained from the groups at similar gestational weeks. In addition, any associations between these biomarkers and different types of pregnancy loss, such as spontaneous abortion and missed abortion, were evaluated. Vitamin B12 and folic acid serum levels were significantly lower in women with miscarriages (P = .019, P < .001, respectively). Homocysteine levels were higher in the patient group (P < .001). Logistic regression analysis showed that a higher homocysteine level was the only predictive factor of miscarriage (P = .001, odds ratio = 0.596); however, folic acid and Vitamin B12 were not predictive factors. There was no significant difference in homocysteine and micronutrient levels between women with missed abortions and women with spontaneous abortions (P > .05). Our results support the continuing evidence of a link between maternal homocysteine levels and fetal loss. However, in exploring the shared pathways in the underlying mechanisms causing the 2 forms of pregnancy loss, maternal blood analysis showed no relationship.


Sujet(s)
Avortement spontané , Acide folique , Homocystéine , Hyperhomocystéinémie , Vitamine B12 , Humains , Femelle , Hyperhomocystéinémie/sang , Hyperhomocystéinémie/épidémiologie , Grossesse , Adulte , Acide folique/sang , Vitamine B12/sang , Études rétrospectives , Avortement spontané/épidémiologie , Avortement spontané/sang , Homocystéine/sang , Études cas-témoins , Turquie/épidémiologie , Marqueurs biologiques/sang , Centres de soins tertiaires
7.
BMC Womens Health ; 24(1): 451, 2024 Aug 09.
Article de Anglais | MEDLINE | ID: mdl-39123143

RÉSUMÉ

BACKGROUND: Pre-eclampsia is a syndrome that chiefly includes the development of new-onset hypertension and proteinuria after 20 weeks of pregnancy. Pre-eclampsia is one of the major causes of mortality and morbidity in Nepal. Hyperhomocysteinemia may be a cause of the endothelial dysfunction provoked by oxidative stress in pre-eclampsia. This study was designed to evaluate the association of homocysteine with Vitamin B12 and folate in patients with pre-eclampsia. METHOD: An observational cross sectional study was performed in the Gynecology and Obstetrics Department of TUTH involving seventy two subjects with pre-eclampsia. Blood pressure, urinary protein levels, serum homocysteine, Vitamin B12 and folate levels were compared in both mild and severe forms of pre-eclampsia. Concentration of Vitamin B12 and folate were measured using Vitros ECI and homocysteine was measured using CLIA. SPSS 23.0 was used to analyze the data. Tests were performed with Mann Whitney Test and Spearman's rank correlation test. A p-value < 0.05 was considered statistically significant. RESULTS: This study showed no significant difference in age and weeks of gestation in both mild and severe forms of pre-eclampsia. Mean concentration of homocysteine was higher (13.1 ± 6.4 micromol/L) in severe Pre-eclampsia as compared to mild cases (7.6 ± 2.8 micromol/L). Mean concentration of folate was lower in severe cases (35.4 ± 24.1 micromol/L) when compared with mild cases of pre-eclampsia (57 ± 23.4 micromol/L). CONCLUSION: Homocysteine levels were increased in severe Pre-eclampsia when compared with mild pre-eclampsia and this finding can be used to predict and prevent complications in patients with pre-eclampsia.


Sujet(s)
Acide folique , Homocystéine , Pré-éclampsie , Centres de soins tertiaires , Vitamine B12 , Humains , Femelle , Pré-éclampsie/sang , Pré-éclampsie/épidémiologie , Grossesse , Homocystéine/sang , Acide folique/sang , Vitamine B12/sang , Népal/épidémiologie , Adulte , Études transversales , Centres de soins tertiaires/statistiques et données numériques , Jeune adulte , Hyperhomocystéinémie/sang , Hyperhomocystéinémie/épidémiologie , Indice de gravité de la maladie , Protéinurie/sang
8.
Nutrients ; 16(15)2024 Jul 25.
Article de Anglais | MEDLINE | ID: mdl-39125297

RÉSUMÉ

Ovarian cancer is the most fatal of all the reproductive cancers within the female population, mainly due to its late diagnosis that limits surgery and medical treatment. Classically, ovarian cancer therapy has included conventional chemotherapy, and other therapeutic approaches are now being used to treat these patients, but the outcomes of the disease are still poor. Therefore, new strategies are needed to improve life expectancy and life quality of ovarian cancer patients. Considering that, we investigated the effect of the nutritional supplement Ocoxin Oral Solution (OOS) in ovarian cancer models. OOS contains several nutritional supplements, some of them with demonstrated antitumoral action. In vitro studies showed that OOS inhibited the proliferation of several ovarian cancer cell lines, especially of those representative of the endometrioid subtype, in a time- and dose-dependent manner. A fast cell death induction after OOS treatment was observed, and when the molecular mechanisms leading to this effect were investigated, an activation of the DNA damage checkpoint was detected, as shown by activation (phosphorylation) of CHK1 and CHK2 kinases that was followed by the phosphorylation of the target protein histone H2AX. When tested in animal models of ovarian cancer, OOS reduced tumor growth without any observed secondary effects. Moreover, such reduction in tumor proliferation was caused by the induction of DNA damage as corroborated by the in vivo phosphorylation of CHK2 and Histone H2AX. Finally, OOS potentiated the action of carboplatin or olaparib, the standard of care treatments used in ovarian clinics, opening the possibility of including OOS in combination with those standard of care agents in patients with ovarian cancer.


Sujet(s)
Prolifération cellulaire , Altération de l'ADN , Tumeurs de l'ovaire , Femelle , Tumeurs de l'ovaire/traitement médicamenteux , Tumeurs de l'ovaire/anatomopathologie , Humains , Altération de l'ADN/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Animaux , Prolifération cellulaire/effets des médicaments et des substances chimiques , Mort cellulaire/effets des médicaments et des substances chimiques , Pyridoxine/pharmacologie , Souris , Acide folique/pharmacologie , Acide folique/administration et posologie , Tests d'activité antitumorale sur modèle de xénogreffe , Compléments alimentaires , Antinéoplasiques/pharmacologie , Administration par voie orale , Vitamine B6/pharmacologie , Vitamine B6/administration et posologie , Histone/métabolisme , Sulfate de zinc , Vitamine B12 , Extraits de plantes , Acide pantothénique , Acide ascorbique
9.
Int J Mol Sci ; 25(15)2024 Jul 23.
Article de Anglais | MEDLINE | ID: mdl-39125597

RÉSUMÉ

The water-soluble vitamin, vitamin B12, also known as cobalamin, plays a crucial role in cellular metabolism, particularly in DNA synthesis, methylation, and mitochondrial functionality. Its deficiency can lead to hematological and neurological disorders; however, the manifestation of these clinical outcomes is relatively late. It leads to difficulties in the early diagnosis of vitamin B12 deficiency. A prolonged lack of vitamin B12 may have severe consequences including increased morbidity to neurological and cardiovascular diseases. Beyond inadequate dietary intake, vitamin B12 deficiency might be caused by insufficient bioavailability, blood transport disruptions, or impaired cellular uptake and metabolism. Despite nearly 70 years of knowledge since the isolation and characterization of this vitamin, there are still gaps in understanding its metabolic pathways. Thus, this review aims to compile current knowledge about the crucial proteins necessary to efficiently accumulate and process vitamin B12 in humans, presenting these systems as a multi-protein network. The epidemiological consequences, diagnosis, and treatment of vitamin B12 deficiency are also highlighted. We also discuss clinical warnings of vitamin B12 deficiency based on the ongoing test of specific moonlighting proteins engaged in vitamin B12 metabolic pathways.


Sujet(s)
Carence en vitamine B12 , Vitamine B12 , Humains , Vitamine B12/métabolisme , Carence en vitamine B12/métabolisme , Voies et réseaux métaboliques , Animaux
10.
Nutr J ; 23(1): 76, 2024 Jul 16.
Article de Anglais | MEDLINE | ID: mdl-39010125

RÉSUMÉ

PURPOSE: This study aimed to identify and quantify the association and investigate whether serum vitamin B12 alone or vitamin B12 combined with folate and plasma total homocysteine (tHcy) levels could be used to predict the risk of acute ischemic stroke. MATERIALS AND METHODS: This retrospective case-control study was conducted in the Department of Neurology, First Affiliated Hospital of Chongqing Medical University. It included 259 inpatients experiencing their first-ever acute ischemic stroke and 259 age-matched, sex-matched healthy controls. Patients were categorized into groups based on the etiology of their stroke: large-artery atherosclerosis (LAAS, n = 126), cardio embolism (CEI, n = 35), small vessel disease (SVD, n = 89), stroke of other determined etiology (ODE, n = 5), and stroke of undetermined etiology (UDE, n = 4). The associations of serum vitamin B12, folate, and plasma tHcy levels with the risk of ischemic stroke were evaluated using multivariable logistic regression analysis. Receiver operator characteristic (ROC) curves were used to assess the diagnostic power of vitamin B12, folate, and tHcy levels for ischemic stroke. RESULTS: Serum vitamin B12 and folate levels were significantly lower in ischemic stroke patients compared to controls, while plasma tHcy levels were significantly higher. The first quartile of serum vitamin B12 levels was significantly associated with an increased risk of LAAS (aOR = 2.289, 95% CI = 1.098-4.770), SVD (aOR = 4.471, 95% CI = 1.110-4.945) and overall ischemic stroke (aOR = 3.216, 95% CI = 1.733-5.966). Similarly, the first quartile of serum folate levels was associated with an increased risk of LAAS (aOR = 3.480, 95% CI = 1.954-6.449), CEI (aOR = 2.809, 95% CI = 1.073-4.991), SVD (aOR = 5.376, 95% CI = 1.708-6.924), and overall ischemic stroke (aOR = 3.381, 95% CI = 1.535-7.449). The fourth quartile of tHcy levels was also significantly associated with an increased risk of LAAS (aOR = 2.946, 95% CI = 1.008-5.148), CEI (aOR = 2.212, 95% CI = 1.247-5.946), SVD (aOR = 2.957, 95% CI = 1.324-6.054), and overall ischemic stroke (aOR = 2.233, 95% CI = 1.586-4.592). For predicting different types of ischemic stroke, vitamin B12 alone demonstrated the best diagnostic value for SVD, evidenced by a sensitivity of 71.0% and negative predictive value of 90.3%, along with the highest positive likelihood ratio (+ LR) for SVD. Vitamin B12 + tHcy + folate are valuable in predicting different types of ischemic stroke, with the most significant effect observed in SVD, followed by LAAS, and the weakest predictive effect in CEI. Additionally, vitamin B12 alone in combination with other indicators, such as folate alone, tHcy alone, and folate + tHcy could reduce negative likelihood ratio (-LR) and improve + LR. CONCLUSIONS: Vitamin B12 was an independent risk factor for acute ischemic stroke. The risk calculation model constructed with vitamin B12 + tHcy + folate had the greatest diagnostic value for SVD.


Sujet(s)
Acide folique , Homocystéine , Accident vasculaire cérébral ischémique , Vitamine B12 , Humains , Vitamine B12/sang , Acide folique/sang , Homocystéine/sang , Études rétrospectives , Femelle , Mâle , Études cas-témoins , Adulte d'âge moyen , Accident vasculaire cérébral ischémique/sang , Accident vasculaire cérébral ischémique/épidémiologie , Sujet âgé , Facteurs de risque , Courbe ROC , Accident vasculaire cérébral/sang
11.
Pediatr Allergy Immunol ; 35(7): e14202, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-39022888

RÉSUMÉ

BACKGROUND: The impact of alternative milk substitutes on the nutritional status of children with cow's milk allergy (CMA), the prevailing cause of food allergies, is unresolved. METHODS: A cross-sectional study was performed in children older than 2 years with IgE-mediated CMA. Patients' clinical characteristics, anthropometric measurements, dietary intake (by 3-day food diary), and biochemical markers of nutritional status were assessed. RESULTS: One hundred two children with CMA (68.6% boys; median age, 3.7 years; 51% multiple food allergies) were evaluated. 44.1% of the children consumed plant-based beverages (PBB), 19.6% therapeutic formula and 36.3% did not consume any milk substitutes. In all age groups, dietary calcium, riboflavin, and vitamin D intake of those who did not use milk substitutes were lower than those who consumed formula or PBB (p < .01). Also in the 2-3 years old age group, dietary zinc (p = .011) and iron intake (p = .004) of the formula-fed group was higher. Formula-fed patients had higher levels of 25-OH vitamin D (µg/L) and serum vitamin B12 (ng/L) than PBB-fed patients (respectively; p < .001, p = .005) and those who did not consume any milk substitute (p < .001). Patients of all ages who did not utilize a milk substitute failed to obtain an adequate amount of dietary calcium. CONCLUSION: The use of milk substitutes positively affects dietary calcium, riboflavin, and vitamin D intake in CMA, but their contribution is variable. Those who do not use milk substitutes are at greater risk inadequate of dietary calcium intake. Personalized nutritional advice, given the clinical diversity and the impact of individual differences, is required.


Sujet(s)
Hypersensibilité au lait , Substituts du lait , État nutritionnel , Vitamine D , Humains , Hypersensibilité au lait/diétothérapie , Hypersensibilité au lait/immunologie , Femelle , Études transversales , Mâle , Enfant d'âge préscolaire , Enfant , Animaux , Vitamine D/sang , Calcium alimentaire/administration et posologie , Riboflavine , Bovins , Vitamine B12/sang
12.
N Z Med J ; 137(1599): 49-54, 2024 Jul 19.
Article de Anglais | MEDLINE | ID: mdl-39024584

RÉSUMÉ

AIMS: To describe the clinical features and outcomes of patients with myelopathy and neuropathy due to recreationally inhaled nitrous oxide. METHODS: We identified patients presenting with nitrous oxide-associated myelopathy from an electronic database of all discharges in a large tertiary hospital between 2016 and 2023. Demographics, clinical features and the results of investigations were recorded. The primary outcome was modified Rankin Scale score (mRS) at least 3 months after hospital discharge where available. RESULTS: There were 12 patients identified, six women, mean (SD) age 27.5 (5.1) years, range 19-47 years. The most common symptoms were numbness, weakness and mental state changes. Four patients used large amounts of inhaled nitrous oxide and also took over-the-counter vitamin B12 supplements. The median (range) hospital length of stay was 8.5 (2-56) days. Functional independence at last assessment (median [range] of 3 [1-34] months after discharge) was achieved in nine of the patients, with three requiring ongoing support for activities of daily living (mRS ≥3). CONCLUSION: Nitrous oxide abuse and its neurological complications are an important public health issue. Clinicians should be aware that some patients who use large amounts of nitrous oxide may self-supplement vitamin B12.


Sujet(s)
Protoxyde d'azote , Maladies de la moelle épinière , Humains , Protoxyde d'azote/effets indésirables , Protoxyde d'azote/administration et posologie , Femelle , Adulte , Mâle , Adulte d'âge moyen , Maladies de la moelle épinière/induit chimiquement , Jeune adulte , Vitamine B12/administration et posologie , Troubles liés à une substance/épidémiologie , Anesthésiques par inhalation/effets indésirables , Anesthésiques par inhalation/administration et posologie , Études rétrospectives , Durée du séjour/statistiques et données numériques
13.
J Assoc Physicians India ; 72(7): 102-105, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38990596

RÉSUMÉ

We report a case series of two patients who had similar skin pigmentation but were caused by vitamin B12 deficiency and Addison's disease. We further discuss the pathophysiology of skin hyperpigmentation in both of these disorders and the response to treatment. Our case report highlights the importance of the identification of simple bedside clinical signs to diagnose reversible causes of skin pigmentation.


Sujet(s)
Maladie d'Addison , Hyperpigmentation , Carence en vitamine B12 , Humains , Carence en vitamine B12/complications , Carence en vitamine B12/diagnostic , Maladie d'Addison/diagnostic , Maladie d'Addison/étiologie , Maladie d'Addison/complications , Hyperpigmentation/étiologie , Hyperpigmentation/diagnostic , Mâle , Femelle , Adulte , Vitamine B12 , Adulte d'âge moyen
14.
Food Nutr Bull ; 45(1_suppl): S16-S22, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38987877

RÉSUMÉ

BACKGROUND: An optimal cobalamin status is necessary for normal neurodevelopment. OBJECTIVE: To give a description of the epidemiology, pathophysiology and diagnostic challenges related to cobalamin insufficiency in neonates and infants in order to prevent its occurence. RESULTS: Inadequate cobalamin status is prevalent among neonates and young infants, due to a high prevalence of maternal cobalamin deficiency, exclusive breastfeeding for extended periods and late introduction of animal food. Cobalamin insufficiency is associated with delayed neurodevelopment and subtle clinical symptoms like feeding difficulties, regurgitations and constipation in young infants. Early diagnosis and treatment of impaired cobalamin status is important to prevent neurologic damage. CONCLUSION: Clinical suspicion of cobalamin insufficiency in infants should infer immediate biochemical testing and a plasma total homocysteine > 5.0 µmol/L indicate cobalamin insufficiency in need of intramuscular treatment with hydroxycobalamin, followed by introduction of animal food after 4 months of age.


Plain language titleVitamin B12 Is Important for Normal Development in Young ChildrenPlain language summaryVitamin B12, also called cobalamin, is found only in animal-sourced food. As low-meat, vegetarian, and vegan diets are increasingly popular in Western countries, vitamin B12 deficiency has become common, also in pregnant women and babies. Vitamin B12 status is essential for normal development and adequate levels of this vitamin is particularly important during pregnancy and the first years of life. In pregnancy, vitamin B12 is transferred from the mother to the fetus, so the baby has a store of this vitamin at birth. However, if the mother has vitamin B12 deficiency or the baby is born premature or with a low birth weight, the vitamin store may be insufficient and the baby may develop vitamin B12 deficiency. Maternal vitamin B12 status is important as long as the baby is exclusively breastfed. Breast milk contains vitamin B12, but the concentration decreases after 4 to 6 weeks and may be too low to support the baby until animal-sourced foods are introduced. The vitamin B12 content in formula milk is higher than in breast milk, and vitamin B12 deficiency is more common in exclusively breastfed babies. Vitamin B12 deficiency is associated with diffuse symptoms in small babies and may be difficult to detect, and the diagnosis have a mean delay of 4 months in this age-group. Typical symptoms are regurgitations or spitting up, constipation, problems with feeding and swallowing, and delayed psychomotor development. Suspicion of vitamin B12 insufficiency in babies should prompt immediate biochemical testing. Plasma total homocysteine is a metabolic marker of vitamin B12 status and can be measured in a blood sample from the baby. A level >5.0 µmol/L indicates probable vitamin B12 insufficiency and the baby should receive vitamin B12 supplementation, followed by introduction of animal-sourced foods at 3 to 4 months of age.


Sujet(s)
État nutritionnel , Carence en vitamine B12 , Vitamine B12 , Femelle , Humains , Nourrisson , Nouveau-né , Allaitement naturel , Homocystéine/sang , Phénomènes physiologiques nutritionnels chez le nourrisson , Vitamine B12/sang , Vitamine B12/administration et posologie
15.
Food Nutr Bull ; 45(1_suppl): S10-S15, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38987881

RÉSUMÉ

BACKGROUND: Little attention has been given to prenatal cobalamin insufficiency in settings where dietary cobalamin intake is presumed adequate, such as populations with habitual intake of foods from animal sources. RESULTS: However, low cobalamin status in women of fertile age has been reported in Europe, United States, and Canada. In India, where cobalamin deficiency is highly prevalent, it has been associated with an increased risk of miscarriage, intrauterine growth retardation, as well as insulin resistance and lower neurodevelopment scores in the offspring. Low cobalamin status in pregnancy has been associated with similar outcomes as those reported in the Indian studies although the evidence is scant and conflicting. CONCLUSIONS: Consideration should be given to maternal cobalamin status in the context of prevention of adverse pregnancy outcomes as well as cobalamin insufficiency both in the mother and the offspring during lactation. Further attention is now justified with the increasing tendency toward plant-based diets. Reference intervals for cobalamin status during each trimester of pregnancy are needed and further investigation of the long-term conse-quences of low cobalamin status during pregnancy for health and development in the offspring is warranted.


Plain language titleInadequate cobalamin status during critical periods of growth and development can have negative consequences on maternal and childhood health.


Sujet(s)
État nutritionnel , Issue de la grossesse , Carence en vitamine B12 , Vitamine B12 , Humains , Grossesse , Femelle , Vitamine B12/administration et posologie , Vitamine B12/sang , Carence en vitamine B12/épidémiologie , Complications de la grossesse , Inde/épidémiologie , Phénomènes physiologiques nutritionnels maternels , Retard de croissance intra-utérin
16.
Food Nutr Bull ; 45(1_suppl): S34-S39, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38987871

RÉSUMÉ

BACKGROUND: Pernicious anemia (PA) is a type of macrocytic anemia caused by autoimmune gastritis. To facilitate timely diagnosis and treatment of PA there is a pressing need for improved understanding among Healthcare providers of the condition's symptoms and diagnostic criteria. OBJECTIVE: This systematic review aims to extend existing clinical knowledge on the presentation of PA by determining which symptoms and clinical complications are reported in published adult case studies. METHODS: Relevant studies were identified through electronic searches of PsycINFO, Embase, and MEDLINE, via OvidSP. During data extraction symptoms were categorized according to the International Classification of Diseases and were grouped based on frequency. RESULTS: Symptoms were documented for 103 adults with a diagnosis of PA; the most frequent symptoms were fatigue (55%), loss of sensation in limbs (32%), excessive weight loss (27%), and a sore tongue (23%). CONCLUSIONS: This review highlights the diverse symptomology of adults who are diagnosed with PA. Most symptoms documented in case studies are consistent with the core signs of B12 and folate deficiencies. Research is needed to identify if there are common clusters of PA symptoms that can be used as prompts for diagnostic testing in patients with suspected B12 deficiency.


Plain language titleA Review of Symptoms of Pernicious AnemiaPlain language summaryThis study reviewed case studies that have been written about adults with pernicious anemia, it has documented the frequency of the core symptoms and the impact these have on health.


Sujet(s)
Anémie pernicieuse , Carence en vitamine B12 , Adulte , Femelle , Humains , Mâle , Anémie pernicieuse/complications , Anémie pernicieuse/diagnostic , Fatigue/étiologie , Carence en acide folique/complications , Gastrite/complications , Gastrite/diagnostic , Vitamine B12/sang , Vitamine B12/administration et posologie , Carence en vitamine B12/complications , Carence en vitamine B12/diagnostic , Perte de poids
17.
Food Nutr Bull ; 45(1_suppl): S3-S4, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38987875

RÉSUMÉ

This supplement of the Food and Nutrition Bulletin is dedicated to the proceedings of "the International B12 Conference in Clinical Practice," held in Rotterdam in June 2023. The conference brought together physicians, scientists, patient groups, and health care professionals with substantial expertise in diagnosing and treating vitamin B12 deficiency from many universities around the world. With a collective commitment to advancing clinical practice and improving patient outcomes, this event was instrumental in addressing the many complex and challenging aspects of vitamin B12 deficiency. The subjects explored at the conference ranged from the latest research findings to real-world case studies, spanning diverse medical disciplines, including pediatrics, obstetrics, neurology, internal medicine, gastroenterology, psychiatry, clinical chemistry, nutrition, public health, biomedical science, and nursing. The broad spectrum of disciplines reflects the multifaceted nature of vitamin B12 deficiency and underscores the necessity of a comprehensive and multidisciplinary approach to its diagnosis and treatment. This supplement aims to distill into a concise and accessible format the knowledge shared by stimulating and provocative presentations at the B12 Conference and to make the information available for the broader scientific and health care community. The compendium bridges the insights generated at the conference and the wider audience of health care practitioners, researchers, and policymakers who recognize the urgency of addressing the critical public health concerns surrounding vitamin B12 deficiency.


Plain language title Vitamin B12 Deficiency in Clinical Practice: Proceedings of an International B12 Conference Plain language summary This supplement focuses on vitamin B12, a crucial micronutrient essential for overall human health. It summarizes the proceedings of the "International B12 Conference in Clinical Practice," held in June 2023 in Rotterdam. The conference gathered experts from various fields, including physicians, scientists, patient groups, and health care professionals, to address the complexities of diagnosing and treating vitamin B12 deficiency. The content covers various topics, from the latest research findings to real-world case studies spanning diverse medical disciplines. The aim is to distill the conference's knowledge into an accessible format for the broader scientific and health care community. The supplement emphasizes the need for a comprehensive and multidisciplinary approach to address Vitamin B12 deficiency by bringing together insights from different disciplines. The manuscripts within the supplement delve into the intricacies of vitamin B12 deficiency offering a synthesis of research findings, clinical insights, and innovative approaches to diagnosis and treatment. The goal is to inspire further research, inform clinical practice, and ultimately improve patient care in the critical areas of nutrition and health care. The supplement expresses gratitude to conference contributors, attendees, and supporters who made the event and publication possible. It aims to contribute to preventing or treating B12 deficiency and improving patients' health and well-being. Whether at the beginning or end of life and all ages in between, addressing B12 deficiency can significantly enhance global health and quality of life.


Sujet(s)
Carence en vitamine B12 , Vitamine B12 , Humains , Congrès comme sujet , Compléments alimentaires , Pays-Bas , Vitamine B12/administration et posologie , Carence en vitamine B12/diagnostic , Carence en vitamine B12/thérapie
18.
Ann Hematol ; 103(8): 3243-3246, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38976007

RÉSUMÉ

BACKGROUND: Vitamin B12 is primarily transported from plasma to cells by Transcobalamin. Deficiency of Transcobalamin is a rare autosomal recessive disorder that results in unavailability of cobalamin in cells and accumulation of homocysteine and methylmalonic acid. CASE REPORT: We report a case of a 2-year-old male child with persistent pancytopenia, recurrent infections, and megaloblastic anemia. Next-generation sequencing identified a novel variant in exon 8 of TCN2 gene. Substantial improvement has been observed following administration of high doses of parenteral methylcobalamin. CONCLUSION: In patients with unresolved pancytopenia and megaloblastic anemia, Transcobalamin deficiency should be investigated and treated promptly to prevent any irreversible and harmful outcome.


Sujet(s)
Transcobalamines , Vitamine B12 , Humains , Mâle , Transcobalamines/génétique , Transcobalamines/déficit , Vitamine B12/usage thérapeutique , Enfant d'âge préscolaire , Carence en vitamine B12/génétique , Carence en vitamine B12/traitement médicamenteux , Anémie mégaloblastique/génétique , Anémie mégaloblastique/traitement médicamenteux , Pancytopénie/génétique , Pancytopénie/étiologie , Exons
19.
Microbiol Spectr ; 12(8): e0021924, 2024 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-39012118

RÉSUMÉ

Interactions between photosynthetic microalgae and bacteria impact the physiology of both partners, which influence the fitness and ecological trajectories of each partner in an environmental context-dependent manner. Thermal tolerance of Chlamydomonas reinhardtii can be enhanced through a mutualistic interaction with vitamin B12 (cobalamin)-producing Sinorhizobium meliloti. Here, we used label-free quantitative proteomics to reveal the metabolic networks altered by the interaction under normal and high temperatures. We created a scenario where the growth of Sinorhizobium requires carbon provided by Chlamydomonas for growth in co-cultures, and survival of Chlamydomonas under high temperatures relies on cobalamin and possibly other metabolites produced by Sinorhizobium. Differential abundance analysis identified proteins produced by each partner in co-cultures compared to mono-cultures at each temperature. Proteins involved in cobalamin production by Sinorhizobium increased in the presence of Chlamydomonas under elevated temperatures, whereas in Chlamydomonas, there was an increase in cobalamin-dependent methionine synthase and certain proteins associated with methylation reactions. Co-cultivation and heat stress strongly modulated the central metabolism of both partners as well as various transporters that could facilitate nutrient cross-utilization. Co-cultivation modulated expression of various components of two- or one-component signal transduction systems, transcriptional activators/regulators, or sigma factors, suggesting complex regulatory networks modulate the interaction in a temperature-dependent manner. Notably, heat and general stress-response and antioxidant proteins were upregulated in co-cultures, suggesting that the interaction is inherently stressful to each partner despite the benefits of mutualism. Our results shed insight into the metabolic tradeoffs required for mutualism and how metabolic networks are modulated by elevated temperature. IMPORTANCE: Photosynthetic microalgae are key primary producers in aquatic ecosystems, playing an important role in the global carbon cycle. Nearly every alga lives in association with a diverse community of microorganisms that influence each other and their metabolic activities or survival. One chemical produced by bacteria that influence algae is vitamin B12, an enzyme cofactor used for a variety of metabolic functions. The alga Chlamydomonas reinhardtii benefits from vitamin B12 produced by Sinorhizobium meliloti by producing the amino acid methionine under high temperatures which are required for Chlamydomonas thermotolerance. Yet, our understanding of this interaction under normal and stressful temperatures is poor. Here, we used quantitative proteomics to identify differentially expressed proteins to reveal metabolic adjustments made by Chlamydomonas and Sinorhizobium that could facilitate this mutualism. These findings will enhance our understanding of how photosynthetic algae and their associated microbiomes will respond as global temperatures increase.


Sujet(s)
Chlamydomonas reinhardtii , Protéomique , Sinorhizobium meliloti , Symbiose , Vitamine B12 , Chlamydomonas reinhardtii/métabolisme , Chlamydomonas reinhardtii/génétique , Sinorhizobium meliloti/métabolisme , Sinorhizobium meliloti/génétique , Sinorhizobium meliloti/physiologie , Vitamine B12/métabolisme , Thermotolérance , Température élevée , Voies et réseaux métaboliques/génétique
20.
Ann Afr Med ; 23(3): 496-500, 2024 Jul 01.
Article de Français, Anglais | MEDLINE | ID: mdl-39034579

RÉSUMÉ

The etiology of cerebral venous sinus thrombosis (CVST) is multifactorial. Although many acquired and genetic factors have been recognized as risk factors, hyperhomocysteinemia (hHcy) is independently associated with CVST. We describe three cases of CVST in this case series. All of them presented with headache. Two patients had papilledema and visual disturbances. On evaluation, there was CVST, and prothrombotic workup showed hHcy. In addition, two of them reported very low Vitamin B12 levels. All of them were treated with low-molecular-weight heparin followed by oral anticoagulation and Vitamin B6, B9, and B12 supplements. All of them responded to treatment, and follow-up imaging studies in two of them showed resolution of thrombosis. hHcy should be considered in the evaluation of CVST, especially in the setting of a pure vegetarian diet. Fortification of the diet with Vitamin B12 may be considered the majority of Indians consume predominantly vegetarian food.


RésuméL'étiologie de la thrombose veineuse cérébrale (CVST) est multifactorielle. Bien que de nombreux facteurs acquis et génétiques aient été reconnus comme facteurs de risque, l'hyperhomocystéinémie (hHcy) est indépendamment associée à la CVST. Nous décrivons trois cas de CVST dans cette série de cas. Tous présentaient des maux de tête. Deux patients avaient un oedème papillaire et des troubles visuels. Lors de l'évaluation, il y avait une CVST et le bilan prothrombotique montrait une hHcy. De plus, deux d'entre eux ont rapporté des niveaux très bas de vitamine B12. Tous ont été traités avec de l'héparine de bas poids moléculaire suivie d'une anticoagulation orale et de suppléments de vitamines B6, B9 et B12. Tous ont répondu au traitement, et des études d'imagerie de suivi chez deux d'entre eux ont montré une résolution de la thrombose. L'hHcy doit être envisagée dans l'évaluation de la (CVST), en particulier dans le contexte d'un régime purement végétarien. La fortification de l'alimentation avec de la vitamine B12 peut être envisagée car la majorité des Indiens consomment principalement des aliments végétariens.


Sujet(s)
Anticoagulants , Thromboses des sinus intracrâniens , Carence en vitamine B12 , Vitamine B12 , Humains , Carence en vitamine B12/complications , Carence en vitamine B12/traitement médicamenteux , Thromboses des sinus intracrâniens/étiologie , Thromboses des sinus intracrâniens/traitement médicamenteux , Mâle , Femelle , Adulte , Vitamine B12/usage thérapeutique , Vitamine B12/administration et posologie , Anticoagulants/usage thérapeutique , Résultat thérapeutique , Aliment enrichi , Hyperhomocystéinémie/complications , Céphalée/étiologie , Héparine bas poids moléculaire/usage thérapeutique , Adulte d'âge moyen , Régime végétarien/effets indésirables
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