• Applied Microscopy
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• v.26 no.4
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• pp.411-420
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• 1996

A zinc-specific method (selenium method) has been employed to identify the zinc-containing cells in the cerebellum of the rats. When rats were allowed to survive 24 hours after the sodium selenite administration, zinc selenide reaction products formed in zinc-containing cellular boutons are retrogradely transported to the somata of those boutons. And the zinc selenide products accumulated in somata of the cells can be rendered visible by silver amplification of developer. Zinc-containing cells identified by the method were Bergmann glial and granule cells. Labeled zinc-containing cells were absent in molecular layer and white matter of the cerebellum. In ultrastructural level, the zinc selenide products were located in lysosomes of somata of the zinc-containing cells.

• Journal of the Korean Dietetic Association
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• v.13 no.4
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• pp.301-310
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• 2007

The purpose of this study was to analyze the relationships among zinc status, protein and phytate intake, and diabetic control indices of type 2 diabetic women. The mean age and the duration of diabetes were respectively 57.9±6.9 years old and 8.0±6.5 years. The mean daily energy intake of diabetic subjects was 1562 kcal. Both the zinc intake (6.2mg/day) and the zinc %RI (% of The Recommended Intake for zinc: 79.5%) of the diabetic participants were significantly lower than those of the control group (respectively p<0.01). As for the diabetic group, the higher the energy intake (kcal/day), the higher were the zinc intake (p<0.001) and %RI for zinc (p<0.001). Zinc intake was positively correlated with the protein (p<0.001), animal protein (p<0.001), and fat intake (p<0.001), but negatively correlated with the carbohydrate intake (p<0.001). Foods with high amount of phytate were the major source of zinc (p<0.01), but did not contribute to high zinc densities. The urinary zinc excretion was twice as high as in the diabetic group compared to the control group (p<0.001). In addition, the urinary zinc loss was positively correlated with the duration of diabetes (p<0.05), hyperglycemia (p<0.001) and insulin resistance (p<0.05). %RI for zinc was negatively correlated with the HbA1C (p<0.05). These results lead us to conclude that the appropriate intake of energy controlled by diet therapy could improve the total zinc intake and %RI for zinc in diabetic women. Also, normal blood glucose level controlled by diet therapy could improve the hyperzincuria. Dietetic practitioners should encourage consumption patterns that provide zinc-rich foods in the form of animal protein to improve the bioavailability as well as the total daily intake of zinc.

• Journal of Nutrition and Health
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• v.57 no.4
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• pp.365-375
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• 2024

Purpose: Zinc is involved in regulating homeostasis and metabolism in the body, and understanding these processes is important for estimating intake requirements. This review aimed to assist in setting the standards for Dietary Reference Intakes for Koreans (KDRIs, 2025) for zinc by examining specific factors associated with role of zinc in the body and using the factorial analysis method. Methods: We reviewed the zinc-specific factors that should be considered when setting the required zinc intake to maintain zinc homeostasis in the body and used the factorial analysis method for estimating zinc requirements for different population groups. Results: Factorial analysis involves estimating the required intake based on various factors that affect zinc metabolism and requirements. The key components and steps involved in determining the zinc dietary reference intake (DRI), particularly the estimated average requirement (EAR), include: 1) Estimating basal requirements, which involves calculating the amount of zinc needed to replace natural losses through the intestinal (feces) and non-intestinal (urine, skin and other body secretions) routes, 2) Accounting for the various biomarkers related to metabolic functions of zinc, 3) Considering physiological requirements for zinc, such as those for growth, development, pregnancy, and lactation since zinc is essential for DNA and protein synthesis, and 4) Estimating the dietary absorption rate of zinc. Conclusion: The factorial analysis for zinc requirement is based on scientific evidence and is tailored to meet the requirements of different population groups, ensuring optimal health and preventing deficiency. It includes considerations of physiological needs, dietary absorption, and population-specific characteristics.

• Journal of Surface Science and Engineering
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• v.25 no.3
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• pp.117-125
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• 1992

In the electrolysis process of zinc plating impurity ions must be removed from zinc chloride plating solution because it's harmful to the current efficiency and the purity of zinc plating. In this study using zinc ball as a prcipitant instead of zinc dust, the fundamental data for continuous cementation process was studied. Based upon two series of experiments that consist of batch experiment with cylindrical zinc specimen and continuous experiment with zinc balls, following results have been obtained. In the continuous experiment all impurity ions have been removed within 1 hour regardless of various experimental conditions.

• Journal of Nutrition and Health
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• v.39 no.3
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• pp.252-263
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• 2006

Zinc is an antioxidant trace mineral, scavenging free radicals and known to be involved in inflammatory reactions. The prevalence of atherogenic diseases such as coronary heart disease (CHD) are increasing in Korean adults of middle age and elderly. The increased cell damage from free radicals and inflammation have been implicated in etiology of CHD, and the evidence is accumulating that low zinc status is involved in the prevalence of this inflammatory atherogenic disease. However, little is known about the zinc status of Korean CHD and its relationship with dietary zinc intake and zinc bioavailabilty. In this study the serum zinc levels of male patients with CHD over 40 yrs. were compared with that of healthy adult males and its associations with dietary zinc intake and zinc bioavailabilty affecting factors were examined. Serum zinc level was measured by HANARO research reactor using neutron activation analysis (NAA) method. The overall proportion of patients with zinc deficiency, serum zinc concentrations below $74.0{\mu}g/dL$ was 32.8% compared to the 10.3% in healthy group. The average serum zinc levels were $80.7{\mu}g/dL\;and\;88.3{\mu}g/dL$ in patients and healthy group, respectively, showing significantly low zinc status in CHD patients compared to healthy group. The intake of nutrients such as energy, carbohydrate, iron, and copper of CHD patients was significantly higher compared to that of the healthy group. In addition, the intake of calcium, iron, and protein from vegetable foods was significantly higher in CHD patients than that of healthy group. The dietary zinc intake was $12.7{\pm}4.5mg$ and $11.5{\pm}6.9mg$ in CHD patients and control group, respectively, which showed no difference. The phytate intake of patients group, which is 1389.0 mg, was significantly higher than the control group which showed 1104.8 mg. However, the ratio of phytate: zinc or phytate * calcium. zinc per 1000 kcal energy intake did not show any difference between two groups. The serum zinc levels did not show any correlation with zinc or factors that affect the bioavailability of zinc. The dietary factors influencing the zinc status were not found in CHD patients.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.2
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• pp.33-42
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• 2011

Zinc plays a key role in genetic expression, cell division, and cell growth and is essential for the functions of more than 450 metalloenzyme. There are high concentrations of zinc in pigment epithelium in bullfrog eye. Zinc deficiency causes night blindness and abnormal dark adaptation. The purpose of this study was to identify ERG (electroretinogram) b-wave sensitivity during light and dark adaptation in bullfrog retina after zinc and zinc chelators treatment such as histidine and TSQ (N-(6-methoxy-8-qunolyl)-p-toluenesulfon amide). Especially, we focused whether histidine act as a zinc chelator in the Muller cell. The results of our study are summarized as follows: 1) Both zinc and histidine elevated ERG b-wave amplitude and threshold in Muller cells by accelerating rhodopsin regeneration time and increased a-peak absorbance during light adaptation. 2) TSQ reduced those by prolonging rhodopsin regeneration time and decrement of a-peak absorbance during light adaptation. 3) Zinc shortened rhodopsin regeneration time and prolonged a-peak absorbance. These results suggested that histidine may act as a zinc-mediated transporter in presynaptic Muller cell membrane rather than zinc chelator and acts as a GABA-receptor inhibitor which blocks $Cl^-$ influx to the postsynapse.

• Nutrition Research and Practice
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• v.7 no.5
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• pp.380-384
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• 2013

Zinc may participate in blood pressure regulation and in the pathogenesis of hypertension. The study examined the relationship between zinc status and blood pressure in obese Korean women. Forty obese women (body mass index (BMI) ${\geq}25kg/m^2$) aged 19-28 years participated in this study. Zinc intake was estimated from one 24 hour recall and 2-day diet records. Serum and urinary zinc concentrations were determined by atomic absorbance spectrophotometry. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured using an automatic sphygmometer. Metabolic variables, such as waist circumference, triglyceride, high density lipoprotein (HDL) cholesterol, fasting glucose, and fasting insulin, were also measured. Dietary zinc intake of obese women was averagely 7.5 mg/day. Serum zinc and urinary zinc concentrations were $13.4{\mu}mol/L$ and $378.7{\mu}g/day$, respectively. Averages of SBP and DBP were 119 mmHg and 78 mmHg. Dietary zinc intake was negatively correlated with SBP after adjusting for energy intake (P < 0.05), but serum and urinary zinc concentrations were not found to be correlated with SBP or DBP. Multivariate linear regression analysis showed that dietary zinc intake was inversely associated with SBP in obese women after adjusting for body weight, energy intake and sodium intake (P = 0.0145). The results show that dietary zinc intake may be an independent risk factor of elevated SBP in obese Korean women.

• Preventive Nutrition and Food Science
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• v.22 no.1
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• pp.1-8
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• 2017

About 20 chemical elements are nutritionally essential for humans with defined molecular functions. Several essential and nonessential biometals are either functional nutrients with antidiabetic actions or can be diabetogenic. A key question remains whether changes in the metabolism of biometals and biominerals are a consequence of diabetes or are involved in its etiology. Exploration of the roles of zinc (Zn) in this regard is most revealing because 80 years of scientific discoveries link zinc and diabetes. In pancreatic ${\beta}$- and ${\alpha}$-cells, zinc has specific functions in the biochemistry of insulin and glucagon. When zinc ions are secreted during vesicular exocytosis, they have autocrine, paracrine, and endocrine roles. The membrane protein ZnT8 transports zinc ions into the insulin and glucagon granules. ZnT8 has a risk allele that predisposes the majority of humans to developing diabetes. In target tissues, increased availability of zinc enhances the insulin response by inhibiting protein tyrosine phosphatase 1B, which controls the phosphorylation state of the insulin receptor and hence downstream signalling. Inherited diseases of zinc metabolism, environmental exposures that interfere with the control of cellular zinc homeostasis, and nutritional or conditioned zinc deficiency influence the pathobiochemistry of diabetes. Accepting the view that zinc is one of the many factors in multiple gene-environment interactions that cause the functional demise of ${\beta}$-cells generates an immense potential for treating and perhaps preventing diabetes. Personalized nutrition, bioactive food, and pharmaceuticals targeting the control of cellular zinc in precision medicine are among the possible interventions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.1
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• pp.80-86
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• 1990

This experiment was conducted to study the effects of dietary zinc and ethanol on the zinc content of serum and tissues. Eight male rats of Sprague-Dawley strain with average weight of 80$\pm$5g were divided into five groups such as C group: ad libitum control diet(100 ppm Zn) plus isocaloric sucrose solution CE group ; ad libitum control diet plus 25% ethanol solution PF group ; pair fed control to zinc deficient diet(5ppm Zn) plus isocaloric sucrose solution ZD grop ; ad libitum zinc deficient diet plus isocaloric sucrose solution and ZDE group ; ad libitum zinc deficient diet plus 25% ethanol solution. The rats were sacrificed after 4 and 7 weeks of feeding periods. The liver weights of ZD and ZDF groups were increased however the weight of testis was decreased in the same groups The content of serum zinc was infiuenced by the dietary zinc level and the amount was significantly decreased in the ZD group. The content of liver zinc was influnced by the dietary zinc level and the amount was decreased by ethanol feeding. The content of testis zinc was significantly low in the ZDE group. The zinc level of feces to be increased by the ethanol feeding.

• Corrosion Science and Technology
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• v.10 no.2
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• pp.43-46
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• 2011

Zinc consumption in a continuous galvanizing line is one of the highest operating cost items in the facility and minimizing zinc waste is a key economic objective for any operation. One of the primary sources of excessive loss of zinc is through the formation of top dross and skimmings in the coating pot. It has been reported that the top skimmings, manually removed from the bath, typically consist of more than 80% metallic zinc with the remainder being entrained dross particles ($Fe_2Al_5$) along with some oxides. Depending on the drossing practices and bath management, the composition of the removed top skimmings may contain up to 2 wt% aluminum and 1 wt% iron. On-going research efforts have been aimed at in-house recovery of the metallic zinc from the discarded top skimmings prior to selling to zinc recycling brokers. However, attempting to recover the zinc entrapped in the skimmings is difficult due to the complex nature of the intermetallic dross particles and the quality and volume of the recycled zinc is highly susceptible to fluctuations in processing parameters. As such, an efficient method to extract metallic zinc from top skimmings has been optimized through the use of a specialized thermo-mechanical process enabling a continuous galvanizing facility to conserve zinc usage on-site. Also, through this work, it has been identified that filtration of discrete dross particles has been proven effective at maintaining the cleanliness of the zinc. Future efforts may progress towards expanded utilization of filters in continuous galvanizing.