Low Serum Zinc Research Articles

Vitamin E, vitamin A, and zinc status are not related to serologic response to influenza vaccine in older adults: an observational prospective cohort study

It has been hypothesized that micronutrient levels play a role in the immune response to vaccination; however, population-level research on the association between micronutrient levels and immune response to influenza vaccination is needed. In this study, we hypothesized that decreasing levels of nutrients would be associated with decreased hemagglutination inhibition (HAI) responses to influenza vaccination. Therefore, the purpose of this study was to determine whether serum vitamin A, vitamin E, or zinc levels are associated with influenza vaccine response determined by HAI titer in adults 65 years or older. Participants in this study included 205 community-dwelling adults 65 years or older who resided in Marshfield, WI, USA, from fall 2008 through spring 2009. Participants received trivalent influenza vaccine and donated blood samples before and 21 to 28 days after vaccination. Prevaccination levels of serum retinol, α-tocopherol, and zinc as well as prevaccination and postvaccination HAI titer levels were measured. No participants were vitamin A or vitamin E deficient; 20% had low serum zinc levels (<70 μg/dL). Continuous variables and categorical quartiles coding for vitamin A, vitamin E, and zinc levels were not related to prevaccination or postvaccination seroprotection or seroconversion for any of the vaccine components (influenza A [H1N1], A [H3N2], or B), after adjusting for age, sex, body mass index, and prevaccination HAI geometric mean titer. In conclusion, our study population showed no association between variations in levels of serum vitamin A, vitamin E, or zinc and influenza vaccine response as measured by HAI in adults older than 65 years. Thus, associations between micronutrients and other measures of vaccine response, such as cell-mediated immune parameters, should also be explored.

The involvement of the GPR39-Zn(2+)-sensing receptor in the pathophysiology of depression. Studies in rodent models and suicide victims

Zinc is one of the most important trace elements in our body. Patients suffering from depression show lower serum zinc levels compared to healthy controls. Zincs antagonism to the glutamatergic system seems to be responsible for mood recovery. Recent years have shown that zinc may regulate neurotransmission via the metabotropic GPR39 receptor. Activation of the GPR39-Zn(2+)-sensing receptor (GPR39) triggers diverse neuronal pathways leading to a cAMP-responsive element binding the protein (CREB) expression, which then induces synthesis of the brain-derived neurotrophic factor and, in turn, activation of the Tropomyosin receptor kinase B (TrkB) receptor. In the present study, we investigated the alteration of the GPR39 in different models of depression, such as zinc deficiency and olfactory bulbectomy and in suicide victims. Additionaly, we focused on CREB-BDNF/TrkB under zinc deficient conditions in mice. To demonstrate depressive-like behaviour, a standard and modified forced swim test (FST) was performed. To evaluate expression of GPR39, CREB, BDNF and TrkB, Western Blot analysis was used. Zinc deficient mice and rats showed decreased GPR39 expression in the hippocampus and frontal cortex. A decreased level of hippocampal and cortical GPR39 was also observed in suicide victims. In contrast, increased GPR39 in the hippocampus of olfactory bulbectomized rats was observed. Additionally, we found a decreased expression of CREB, BDNF and TrkB only in the hippocampus of zinc-deficient mice. Our present study demonstrates the associacion of the GPR39 Zn(2+)-sensing receptor in the pathomechanism of depression. Down-regulation of CREB, BDNF, TrkB and GPR39 receptor found under zinc-deficient conditions in the hippocampus, may play an important role in the pathophysiology of mood disorders, since most of patients suffering from depression show lower serum zinc.

The Effect of Serum Copper and Zinc Levels on the Immunity of Children

Background: the proper zinc and copper levels seem very important to our immune system. Due to the association of copper and zinc in many enzymes structures, and also the important role of them in the immune system most of the evaluations have considered copper and zinc together. Objective: To evaluate serum copper and zinc levels in children suffering from pneumonia and its relation to CD34+ cell. Study design: 37 patients (21 males and 16 females)with proven diagnosis of pneumonia these patients were selected as one every three cases admitted to chest unit of Pediatric Department, Zagazig University Hospital during the year 2012,their ages ranging from 6 months to 5 years and 37 healthy children(19 males and 18 females) were studied as control group. Results: WBCs, platelets, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), neutrophils and lymphocytes were highly significantly higher in patients than controls while hemoglobin, zinc, copper, CD34+ levels were highly significantly lower. There were highly significant positive correlation between CD34 and both copper and zinc levels.Conclusion: Low serum copper and zinc levels may be a contributing factor to the pathophysiology of community acquired pneumonia through its effect on the immune system.

Effect of micronutrient deficiency on QuantiFERON-TB Gold In-Tube test and tuberculin skin test in diagnosis of childhood intrathoracic tuberculosis

Data on performance of QuantiFERON-TB Gold In-Tube test (QFT) and tuberculin skin test (TST) in children with active tuberculosis from high burden countries in the context of micronutrient deficiency are scarce. The objective of this study was to evaluate the effect of micronutrient deficiency on the performance of TST and QFT in children with intrathoracic tuberculosis. Children with probable intrathoracic tuberculosis underwent TST, QFT, gastric lavages and induced sputum examination for AFB (Acid-Fast Bacilli) smear and culture. Zinc, copper, ferritin and vitamin D were measured on stored serum samples. The study used cross-sectional data at initiation of anti-tubercular therapy. Three hundred and sixty-two children (median age 115.5 months (interquartile range: 73, 144), 200 (55.3%) girls) were enrolled in the study. Microbiological confirmation of tuberculosis could be obtained in 128 patients. TST and QFT were positive in 337 (93%) and 297 (82%) children, respectively. Performance of both the tests was unaffected by weight-for-age and height-for-age 'z-scores' or by serum copper levels. TST was not affected by serum zinc and ferritin levels. Children with negative QFT results had lower mean serum zinc level (P=0.01) and higher ferritin levels (P=0.007) as compared to those with positive test. Higher proportion of children with positive TST were vitamin D deficient/insufficient (P=0.003). Micronutrient status, especially serum levels of zinc, may influence the performance of QFT in children with intrathoracic tuberculosis. Considering the high prevalence of zinc deficiency in developing countries, QFT should be used cautiously for diagnosing tuberculosis.

Serum zinc levels as a predictor of clinical features and outcome of paediatric acute lower respiratory infections in Nigeria

Background: Malnutrition, especially macronutrient deficiency, has been shown to be interrelated with ALRI-related morbidity and mortality. However the import of zinc deficiency has only recently become the focus of research attention.Objective: The current study was carried out in Ilorin, Kwara State, Nigeria to determine the relationship between serum zinc levels, clinical features and outcome in hospitalized children with acute lower respiratory infections(ALRI).Method: A descriptive crosssectional hospital-based study involving 120 children aged two months to five years with ALRI. Socio-demographic, clinical and laboratory data were obtained. The serum zinc was analyzed with a Jenway™ spectrophotometer after initial preparation with theQuantiChrom™ zinc assay kit.Results: Children with tachypnoea and crepitations had significantly lower mean serum zinc levels compared to the corresponding values in those without these features (each p&lt;0.05). Significantly higher mean serum zinc level was recorded in children with grunting respiration compared with thosewithout grunting (p=0.028). Agerelated tachypnoea, grunting, and crepitations remained significant (each p&lt;0.05) following a linear regression analysis. The mean serum zinc level in children with multiple complications was significantly lower than the corresponding level recorded in children who had one complication, p=0.020. No significant differencewas found between the mean serum zinc level of the children who were discharged compared with the corresponding level recorded in those that died, p=0.589.Conclusion: The presence of crepitations had the strongest clinical association with a low serum zinc level. Children managed for ALRI would benefit from post-treatment zinc supplements and appropriate zinc-rich sources of food at discharge.Keywords: Children zinc respiratory infections

Serum zinc values in children with congenital heart disease

Some children with congenital heart diseases (CHD) may have increased pulmonary blood flow that causes recurrent bronchopneumonia and congestive heart failure. Serum zinc is reduced in children with pneumonia and patients on diuretics. To evaluate the serum zinc level of children with CHD and their controls without CHD. The subjects were 41 children with CHD confirmed on echocardiography recruited from a paediatric cardiology clinic in a tertiary centre in Nigeria. The controls were 41 children without CHD. Biodata and anthropometric measurements were taken. The serum zinc was determined using atomic absorption spectrophotometer method. The mean difference in the serum zinc of the subjects 101.3 ± 21.6 µg/dl and controls 106.5 ± 18.3 µg/dl, was not significant, p = 0.351. The subjects with pneumonia had a lower mean serum zinc value 89.5 ± 15.0 µg/dl compared to those without pneumonia 103.9 ± 22.2 µg/dl, p = 0.006. The mean serum zinc values of the subjects on diuretic was not statistically different from those not on diuretic, p = 0.599. The serum zinc levels of the subjects and controls were not significantly different. Children with CHD and pneumonia had significantly lower zinc level compared to those without pneumonia.

Psychological Stress-Induced Lower Serum Zinc and Zinc Redistribution in Rats

In humans, long-term exposure to uncontrollable and unpredictable life stressors is a major precipitant in the development of depressive disorders. There are strong evidences that depression is accompanied by lower serum zinc. The aim of present study is to assess the effects of repeated psychological stress (PS) on the zinc metabolism in rat. The rats were divided into control group and PS group which were subdivided into three subgroups: 7-day group, 14-day group, and recovery group (ten rats in each subgroup). PS model was created by a communication box which contains room A and room B. Rats in room A were only exposed to the responses of rats which were randomly given electrical shock for 30 min in room B. PS was given to rats for 30 min every morning for 14 days. The serum corticosterone (CORT), zinc in serum and tissues, and zinc apparent absorption after PS exposure were investigated. The results showed that the serum CORT increased and serum zinc decreased after 7 and 14 days of PS treatment. The zinc concentration in the liver was increased by 14 days PS exposure, whereas its concentration in the hippocampus was decreased by 7 and 14 days of PS exposure. There were no significant changes in zinc concentration in the heart, spleen, kidney, duodenum, cortex, and cerebellum. A decrease in the zinc apparent absorption was observed in the 7- and 14-day PS groups. The increased serum CORT and liver zinc concentrations and decreased serum zinc and apparent absorption of zinc recovered to normal concentrations 7 days away from PS exposure. The results suggest that PS could induce lower serum zinc, which might be correlated with decreased zinc absorption in the small intestine and increased liver zinc accumulation after PS exposure. The consequent effects of decreased hippocampal and serum zinc and increased CORT concentration after PS exposure on stress-related diseases await further research.

Comparative evaluation of serum levels of main minerals and postmenopausal osteoporosis

ObjectiveThe purpose of this study was to determine the relationship between serum main minerals and postmenopausal osteoporosis. Study designA total of 728 postmenopausal women were included in this study. Women were separated into two groups according to presence or absence of osteoporosis (OP). BMD was measured in total femur (TF), femoral neck (FN) and lumbar spine (L1–L4) by dual-energy X-ray absorptiometry. Risk factors for OP were recorded by using a structured questionnaire. Main outcome measuresWomen's blood were collected and serum concentrations of iron, copper, zinc, sodium, potassium, magnesium, calcium, ionized calcium, inorganic phosphorus were measured. ResultsLow serum copper levels were significantly associated with OP according to BMD values for TF, FN and L1–L4. There was a significant relationship between low serum zinc levels and OP for L1–L4 spines. Low iron serum levels were also significantly associated with OP in BMD measurements of TF. Low serum magnesium levels had significant association with OP of L1–L4 spines and TF. Serum levels of calcium, ionized calcium, potassium, sodium and inorganic phosphorus were not associated with OP. ConclusionsIn postmenopausal women, the low serum levels of copper, zinc, iron and magnesium appear to be an important risk factor for OP.

First Trimester Dietary Intake, Biochemical Measures, and Subsequent Gestational Hypertension Among Nulliparous Women

The purpose of this study was to evaluate the relationships between first-trimester dietary factors and biochemical measures and subsequent risk of gestational hypertension. This pilot study used a prospective design utilizing a convenience sample of nulliparous women enrolled at their first prenatal visit. A total of 57 women completed the study. Participants were divided into 2 groups for data analysis: normotensive pregnancy and gestational hypertension. Nearly one-quarter of study participants (22.8%) developed gestational hypertension, of whom 84.6% had significant proteinuria meeting the criteria for preeclampsia. There were no significant differences in micronutrient or macronutrient dietary intakes between groups. Serum iron and zinc levels were lower for the gestational hypertension group compared with the normotensive pregnancy group (P ≤ .01). Low serum zinc levels were related to a risk of developing gestational hypertension (adjusted odds ratio, 0.930; 95% confidence interval, 0.872-0.992). Ensuring adequate intake of zinc and monitoring serum zinc levels in nulliparous pregnant women may help to prevent or contribute to early detection of gestational hypertension.

Serum zinc level in children presenting with febrile seizures

To determine the frequency of low serum zinc level in children presenting with febrile seizures at The Children's Hospital and the Institute of Child Health (CH/ICH) Multan. This is an observational cross sectional study conducted at the Department of Pediatric Medicine, The Children's Hospital and the Institute of Child Health, Multan from September 2010 to March 2011. Children (6 months to 6 years of age) presenting with febrile seizures who satisfied inclusion and exclusion criteria were enrolled for the study. Cause of fever was determined after detailed history, physical examination and relevant investigations. Four milliliters centrifuged blood sample was preserved in acid washed test tube. Separated serum was used to measure serum zinc level by employing Randox kit on auto-analyzer in all cases. The outcome variable (serum zinc level) was recorded on a predesigned proforma. Out of 100 enrolled children, there were 66 (66%) male with male to female ratio of 1:0.52. Mean age of the children was 23.97±14.45 months. Upper respiratory tract infection was the most frequent cause of fever apparent in 24 children (24%) followed by tonsillitis 17 (17%), pneumonia 16 (16%), urinary tract infection 16 (16%), otitis media 15 (15%), and bronchiolitis 12 (12%). Frequency of low serum zinc level was 26% in children with febrile seizures. Zinc deficiency could be a potential risk factor for febrile seizure in children.

A systematic review and meta-analysis of the use of oral zinc in the treatment of hepatic encephalopathy

Background and aimBecause low serum zinc levels precipitate hepatic encephalopathy, zinc supplementation is considered a potential therapeutic option. The aim of this study was to assess the effects of oral zinc supplementation in the treatment of hepatic encephalopathy.MethodsFor this systematic review and meta-analysis, data sources included electronic databases (CENTRAL, MEDLINE, EMBASE) and manual searching. Randomized clinical trials of adult patients diagnosed with liver cirrhosis and hepatic encephalopathy were included. The types of interventions considered were any oral zinc supplementation versus no intervention, placebo, or other interventions for the management of hepatic encephalopathy. The data were analyzed by calculating the RR for each trial and expressing the uncertainty as 95% CI. Continuous data were analyzed by calculating the standard mean differences (SMD) between groups within each trial and their 95% CI. Statistical heterogeneity was defined as a P-value > 0.10 (χ2) or I2 > 25%.ResultsFour trials with a total of 233 patients were included. Oral zinc supplementation was associated with a significant improvement in performance on the number connection test (SMD –0.62; 95% CI –1.12 to –0.11) reported in three trials (n = 189), but not with encephalopathy recurrence reduction (RR 0.64; 95% CI 0.26 to 1.59) reported in two trials (n = 169). Other clinically significant outcomes (mortality, liver related morbidity, quality of life) were not reported.ConclusionOral zinc supplementation improved performance on the number connection test, but no evidence about other clinical or biochemical outcomes was available.

Associations among Dietary Zinc Intakes and Biomarkers of Zinc Status before and after a Zinc Supplementation Program in Guatemalan Schoolchildren

The associations among dietary zinc intakes and biomarkers of zinc status are unknown in apparently healthy children at high risk for zinc deficiency. To assess associations among zinc-related parameters in a sample of Guatemalan school-aged children. We assessed total dietary intakes and biomarkers of zinc status before and after receiving 6 months of zinc supplementation or placebo in 691 Guatemalan schoolchildren aged 6 to 11 years. Most of the children also received zinc-fortified milk from a government program that started shortly after the trial began. We assessed associations between zinc intakes and serum zinc, alkaline phosphatase (ALP), and albumin. At baseline, the prevalence of serum zinc < 65 microg/dL and dietary zinc intake below Estimated Average Requirements (EAR) (< 4 and < 7 mg/day for children < 9 and > or = 9 years, respectively) were 21.6% and 39.4%, respectively. Pearson correlations between serum zinc concentration and dietary zinc intake, serum ALP, and serum albumin were r = 0.07, 0.15, and 0.07, respectively. At the 6-month follow-up, low serum zinc and low total (diet plus fortified milk) zinc intakes were observed in 1.2% and 0.0% of children in the zinc-supplemented group and 4.0% and 34.1% in the placebo group, respectively. Pearson correlations between serum zinc concentration and total zinc intake, serum ALP, and serum albumin were 0.10, 0.06, and -0.11 in the zinc-supplemented group and -0.04, 0.05, and 0.01 in the placebo group, respectively. Zinc intake was inconsistently associated with markers of serum zinc concentration. Zinc fortification or supplementation attenuated the associations.

Effect of vegetarian diets on zinc status: a systematic review and meta‐analysis of studies in humans

Plant-based diets contain less saturated fat and cholesterol and more folate, fibre and phytochemicals than omnivorous diets, but some micronutrients, especially zinc, are poorly bioavailable. The findings of studies exploring the zinc intake and zinc status in populations that habitually consume vegetarian diets are inconsistent. This study aims to investigate the effects of plant-based diets on dietary zinc intake and status in humans using systematic review and meta-analysis techniques. Thirty-four studies were included in the systematic review. Of these, 26 studies (reporting 48 comparisons) compared males and/or females consuming vegetarian diets with non-vegetarian groups and were included in meta-analyses. Dietary zinc intakes and serum zinc concentrations were significantly lower (-0.88 ± 0.15 mg day(-1), P < 0.001 and -0.93 ± 0.27 µmol L(-1), P = 0.001 respectively; mean ± standard error) in populations that followed habitual vegetarian diets compared with non-vegetarians. Secondary analyses showed greater impact of vegetarian diets on the zinc intake and status of females, vegetarians from developing countries and vegans. Populations that habitually consume vegetarian diets have low zinc intakes and status. Not all vegetarian categories impact zinc status to the same extent, but a lack of consistency in defining vegetarian diets for research purposes makes dietary assessment difficult. Dietary practices that increase zinc bioavailability, the consumption of foods fortified with zinc or low-dose supplementation are strategies that should be considered for improving the zinc status of vegetarians with low zinc intakes or serum zinc concentrations at the lower end of the reference range.

Up-regulation of Slc39A2(Zip2) mRNA in peripheral blood mononuclear cells from patients with pulmonary tuberculosis

Zinc is the most common trace mineral after iron in the human body. In organisms, zinc transporters help zinc influx and efflux from cells. A previous study has reported that Zip2 was up-regulated over 27-fold in human monocytic THP-1 cells, when intracellular zinc was depleted by TPEN. Our study found Zip2 was over-expressed in leukocytes of asthmatic infants, especially those in which the serum zinc level was lower than those in healthy infants. Pulmonary tuberculosis (PTB) patients have significantly low serum zinc levels. Here we investigated whether Zip2 level was changed in the patients with PTB. Zip2 mRNA and protein levels in peripheral blood mononuclear cells (PBMC) from PTB (n1=23) and healthy controls (n2=42) were detected by quantitative real-time PCR and western blot, respectively. mRNA expression levels of another four zinc transporters, Zip1, Zip6, Zip8 and ZnT1, were detected by quantitative real-time PCR. Zip2 mRNA level was significantly up-regulated in PTB patients (P=0.001), and Zip8 mRNA level was significantly down-regulated compared with control individuals (P<0.001). In contrast, there were no significant changes in mRNA levels of Zip1, Zip6 and ZnT1 in either group (P>0.05). Zip2 protein expression levels increased in PTB patients compared with control individuals. Our study found that knockdown of ZIP2 with siRNA caused a decrease in Zip2 levels in PBMC of PTB patients, while reducing the expression of INF-γ (P<0.01) and increasing the expression of IL-6(P<0.01). These data provide evidence that increased expression of Zip2 gene is closely associated with immunity of PTB patients, suggesting that the Zip2 gene may play a key role in the initial infection control of the human body, by promoting and maintaining the immune response of adaptive T cells.

Baseline Serum Concentrations of Zinc, Selenium, and Prolactin in Critically Ill Children*

To describe serum concentrations of zinc, selenium, and prolactin in critically ill children within 72 hours of PICU admission, and to investigate relationships between these immunomodulators and lymphopenia. An analysis of baseline data collected as part of the multicenter Critical Illness Stress Induced Immune Suppression (CRISIS) Prevention Trial. PICUs affiliated with the Collaborative Pediatric Critical Care Research Network. All children enrolled in the CRISIS Prevention Trial that had baseline serum samples available for analysis. None. Of 293 critically ill children enrolled in the CRISIS Prevention Trial, 284 had baseline serum samples analyzed for prolactin concentration, 280 for zinc concentration, and 278 for selenium concentration within 72 hours of PICU admission. Lymphocyte counts were available for 235 children. Zinc levels ranged from nondetectable (< 0.1 μg/mL) to 2.87 μg/mL (mean 0.46 μg/mL and median 0.44 μg/mL) and were below the normal reference range for 235 (83.9%) children. Selenium levels ranged from 26 to 145 ng/mL (mean 75.4 ng/mL and median 74.5 ng/mL) and were below the normal range for 156 (56.1%) children. Prolactin levels ranged from nondetectable (< 1 ng/mL) to 88 ng/mL (mean 12.2 ng/mL and median 10 ng/mL). Hypoprolactinemia was present in 68 (23.9%) children. Lymphopenia was more likely in children with zinc levels below normal than those with zinc levels within or above the normal range (82 of 193 [42.5%] vs. 10 of 39 [25.6%], p = 0.0498). Neither selenium nor prolactin concentrations were associated with lymphopenia (p = 1.0 and p = 0.72, respectively). Serum concentrations of zinc, selenium, and prolactin are often low in critically ill children early after PICU admission. Low serum zinc levels are associated with lymphopenia, whereas low selenium and prolactin levels are not. The implications of these findings and the mechanisms by which they occur merit further study.

Enigma of Low-Serum Zinc, Selenium, and Prolactin With Lymphopenia*

Department of PediatricsAdvanced Pediatrics CentrePostgraduate Institute of Medical Education and ResearchChandigarh, India *See also p. e202. The author has not disclosed any potential conflicts of interest.

Is serum zinc level associated with prediabetes and diabetes?: a cross-sectional study from Bangladesh.

AimsTo determine serum zinc level and other relevant biological markers in normal, prediabetic and diabetic individuals and their association with Homeostasis Model Assessment (HOMA) parameters.MethodsThis cross-sectional study was conducted between March and December 2009. Any patient aged ≥30 years attending the medicine outpatient department of a medical university hospital in Dhaka, Bangladesh and who had a blood glucose level ordered by a physician was eligible to participate.ResultsA total of 280 participants were analysed. On fasting blood sugar results, 51% were normal, 13% had prediabetes and 36% had diabetes. Mean serum zinc level was lowest in prediabetic compared to normal and diabetic participants (mean differences were approximately 65 ppb/L and 33 ppb/L, respectively). In multiple linear regression, serum zinc level was found to be significantly lower in prediabetes than in those with normoglycemia. Beta cell function was significantly lower in prediabetes than normal participants. Adjusted linear regression for HOMA parameters did not show a statistically significant association between serum zinc level, beta cell function (P = 0.07) and insulin resistance (P = 0.08). Low serum zinc accentuated the increase in insulin resistance seen with increasing BMI.ConclusionParticipants with prediabetes have lower zinc levels than controls and zinc is significantly associated with beta cell function and insulin resistance. Further longitudinal population based studies are warranted and controlled trials would be valuable for establishing whether zinc supplementation in prediabetes could be a useful strategy in preventing progression to Type 2 diabetes.

Extruded Rice Grains Fortified with Zinc, Iron, and Vitamin A Increase Zinc Status of Thai School Children When Incorporated into a School Lunch Program

Iron (Fe), zinc (Zn), and vitamin A (VA) deficiencies are common among children in developing countries and often occur in the same individual. Rice is widely consumed in the developing countries of Asia and the low phytate in polished rice makes it ideal for Zn and Fe fortification. Triple-fortified rice grains with Zn, Fe, and VA were produced using hot extrusion technology. The main objective of the present study was to determine the impact of triple-fortified extruded rice on Zn status in school children in Southern Thailand. Although serum zinc was the main outcome indicator, Fe and VA status were also assessed. School children with low serum zinc (n = 203) were randomized to receive either triple-fortified rice (n = 101) or natural control rice (n = 102) as a component of school lunch meals for 5 mo. Serum Zn, hemoglobin, serum ferritin, serum retinol, and C-reactive protein were measured at baseline and at the end of the study. After the intervention, serum Zn increased (P < 0.05) in both the fortification (11.3 ± 1.3 μmol/L) and control (10.6 ± 1.4 μmol/L) groups, most likely due to the proper implementation of the school lunch and school milk programs, with the increase greater in the group receiving the triple-fortified rice (P < 0.05). Because the children were not Fe or VA deficient at baseline, there was no change in Fe or VA status. We conclude that Zn fortification of extruded rice grains is efficacious and can be used to improve Zn status in school children.

Association between serum zinc concentration and the Plasmodium falciparum antibody titer among rural villagers of Attapeu Province, Lao People's Democratic Republic

Experimental studies have indicated that low serum zinc levels affect immune responses. However, few studies have evaluated the impact of serum zinc levels on antibody responses in the field in developing countries. We investigated an association between the anti-Plasmodium falciparum (Pf) antibody (immunoglobulin G) titer and serum zinc concentration among villagers in rural areas of the Lao People's Democratic Republic. Blood samples were collected to detect Pf infection. An enzyme-linked immunosorbent assay (ELISA) was used to measure the anti-PfIgG antibody titer. Each serum sample was assayed to measure the concentration of zinc. Pearson's correlation coefficient was applied to the association between zinc concentration and anti-PfIgG antibody titers. Multiple linear regression analysis was used to assess the association between zinc concentration and anti-PfIgG antibody titers, controlling for age and albumin level. Of 71 blood samples, 40 were Pf positive and 31 were Pf negative. The median serum zinc concentrations were 56.0μg/dl in the Pf-positive group and 62.5μg/dl in the Pf-negative group. The median anti-Pf titers were 833.4 in the positive group and 1237.2 in the negative group. Unexpectedly, there was a negative correlation between serum zinc and anti-Pf IgG antibody titers; the correlation coefficient were -0.453 and (p=0.003) in the positive group and -0.461 (p=0.009) in the negative group. The results of this study indicated sustained antibody responses among the villagers, who had likely been exposed to malaria periodically throughout their lives. Further studies are necessary to determine the conditions in which zinc could be effective against malaria.

Nutritional Status of Patients with Cutaneous Leishmaniasis from a Tropical Area of Bolivia, and Implications for Zinc Bioavailability

Macro and micronutrient deficiencies are a significant problem among people in rural areas in developing countries. Deficiencies may lead to an impaired immune system making the organism vulnerable to infections and diseases. In this paper, the dietary intake, anthropometric measurements, zinc and copper levels in serum, of patients with cutaneous leishmaniasis (CL) are compared with a group of healthy controls and reference values. Results showed no significant differences in most nutrient intake or anthropometrics between patients and controls. However, serum zinc level of patients (80 μg/dl) was significantly lower (P 0.001) than in controls (85 μg/dl), likely explained by the presence of leishmaniasis. The median serum zinc level in both groups was below the reference values, even though their median zinc intake met the zinc recommendations from WHO. Consequently, besides the presence of leishmaniasis, serum zinc levels may be compromised by inhibitory components in their diet, such as phytates, as it is shown by the molar ratio phytate:zinc (Phy:Zn) that was between 11 and 19, while 15 is the level said to compromise zinc status. There were significant (P 0.05) negative correlations between serum zinc and Phy:Zn, for patients (r = - 0.413) and controls (r = - 0.410). In conclusion this study shows that patients with CL in Chapare, Bolivia had low serum zinc levels due to the leishmaniasis per se and the decreased zinc bioavailability in their diet. CL infection was not in direct association with the nutritional status indicated by the anthropometric or dietary assessments. However, dietary intake showed 5 essential nutrients below the nutrient recommendation in both groups.