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COVID-19 is an infectious disease caused by the SARS-CoV-2 virus, and it spreads quickly without symptoms sometimes among people and leads to various complications in the body, there is a clear increase in D-dimer and ferritin as a result of this infection, these inflammatory proteins are like a ticking bomb for inflammation by release a lot of inflammatory cytokines like IL-6 that appeared with the cytokine storm in COVID-19 patients, therefore Sinopharm and Pfizer's vaccines are among the most important vaccines used in Iraq to prevent infection, that is why the aim of this study was to know the effect of the Covid-19 vaccines on the immune response by studying some immune markers by collected the Blood from infected and convalescent patients and according to the periods of vaccinations (T0 before vaccination, T1 after 21 days of the first dose, and T2 after 21 days of the second dose) and the three marker tests required for the study (D-dimer, ferritin, and interleukin-6) were performed according to the diagnostic leaflet of each kit. The results showed highly significant differences in infected and convalescent patients when compared with vaccinated subjects with Pfizer or Sinopharm for all three markers and don't show any significant differences in vaccinated subjects with Pfizer or Sinopharm vaccine after the second dose. And the study concluded that the vaccine does not stimulate a harmful inflammatory response, as in the case of infection. [ABSTRACT FROM AUTHOR]

Diabetes mellitus is the most common metabolic endocrine disorder which is characterized by hyperglycemia. Diabetes mellitus is associated with many secondary complications like retinopathy, neuropathy, nephropathy, diabetic foot, cardiovascular disorder etc. Iron is the most abundant trace element in the body, and almost all iron occurs bound to proteins. Because of its ability to switch back and forth between ferrous and ferric oxidation states, iron is both a strong biological oxidant and reductant. Diabetes is linked to iron deficiency. Although the association connecting iron and diabetes was originally discovered in pathological situations such as hereditary hemochromatosis and thalassemia, increased dietary iron levels also lead to diabetes. Iron is involved in the pathophysiology of diabetes, which is mediated by both-cell failure and insulin resistance. Iron has a function in metabolic control in most tissues involved in fuelhomeostasis, with the adipocyte serving as an iron sensor in particular. Oxidant stress, regulation of adipokines, and intracellular signal transduction pathways are among the underlying molecular processes mediating these effects, which are diverse and poorly absorbed. [ABSTRACT FROM AUTHOR]

We performed a prospective study to evaluate iron profile in type 2 Diabetes Mellitus (T2 DM) in creating of progress disease. This study included 60 person showed healthy and any disease freely as well 90 patients with duration of disease from less than 5 years to more than 16 years. Blood samples was collected to measure serum iron and ferritin and total iron binding capacity(TIBC) in T2DM patients and non-diabetes persons. There was a significant increase in glycemic and iron profile in patients compared with the control group, glycemic value was not affected with the duration of disease, while the increase in the value of iron and ferritin accompanied by the duration of disease. Iron circulation raise may act a valuable factor in complication of type 2 Diabetes Mellitus disease. [ABSTRACT FROM AUTHOR]

A novel epidemic infection Coronavirus-19 (COVID-19) considered as one of the challenges in sustainable development. A new-onset of hyperglycaemia has been observed between many COVID-19 patients. The clear explanation of this elevation in fasting plasma glucose (FPG) was debuted. Here we investigate whether this increase is due to impaired insulin secretion or insulin resistance. 269 participants, group 1 (control, n = 46) group 2 (COVID-19 patients, n = 223). 27 Patients were excluded due to missing of their FPG results. FPG, liver enzymes (ALT, AST, and Alk. Phosphatase), b.urea, s.creatinine, s. insulin, C-peptide, D-dimer, and s.ferritin were measured. Our results showed that FPG was increased in 82% (161) patients and this increase was positively correlated with ferritin (r20.039, P-value 0.0013). There is no correlation between FPG with liver enzymes (ALT and AST). The level of insulin hormone and c-peptide were normal. Because there were no increase in insulin or c-peptide and the only relationship was between FPG and ferritin. Therefore, we concluded that COVID-19 infection could cause insulin resistance. [ABSTRACT FROM AUTHOR]

Treatment of COVID-19 has been a major challenge during the current pandemic. Various parameters including clinical symptoms and laboratory markers were used for predicting severity of the disease. However, limited data has been available regarding role of inflammatory markers used for monitoring the progression of the disease. Current study aimed to investigate whether serum ferritin level can be used a marker of rapid progression of the disease and if it can predict mortality in COVID-19 cases. The present study included 40 qRT-PCR positive patients who succumbed to COVID-19 as severe group, and 40 patients who were hospitalized but recovered from the disease as the mild group. Demographic details and laboratory data of the patients were obtained and evaluated retrospectively. Spearman's rank correlation was done between serum ferritin and age in patients of differing severity of the disease. Receiver operating curve (ROC) was used for identifying best cut-off level of ferritin for classification of severity. The mean age of the non-survivor (severe/critically ill group) had a tendency to be higher than the mean age of those of the survivors (mild group). Serum ferritin was significantly higher among severe COVID-19 cases compared to mild (p<0.0001). In ROC analysis area under the curve was 0.790. Here we report for the first time, a cut off value for ferritin (277 ng/ml), which can differentiate between the various hospitalization outcomes of COVID-19 patients. There was no significant association observed in age distribution with severity of the disease. Circulating ferritin level not only reflect acute phase response but rather plays critical role in inflammation of COVID-19 disease. Ferritin a natural organometallic complex is a widely available marker, that can be used for monitoring and predicting disease progression thus it can guide clinicians for the effective management of COVID-19. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 is an infection caused by severe acute respiratory syndrome coronavirus-2. The clinical spectrum of this illness ranges from asymptomatic infection to acute respiratory distress syndrome (ARDS), circulatory shock, multiorgan failure, and ultimately death. The aims of this study are to assess of lymphocyte count, to study of acute phase proteins inflammatory biomarker which include ferritin, lactate dehydrogenase, and D-dimer, and to study of renal function markers which include blood urea nitrogen and serum creatinine. The data accumulated throughout this selective case control study which were extended from September 1st, 2020, to December 1st, 2020. A total of 176 human serum samples were collected, and subdivided into four groups moderate, sever, critical and control, each group comprised of 44 individuals. Results: The data was analyzed using the SPSS-20 statistical package that was available (Statistical Packages for Social Sciences-version 20). The results showed a highly significant decrease in the mean of Lymphocyte in Covid-19 patients when compared to the control group, p.value = 0.000. But Lymphocyte showed no significant differences among moderate, severe, and critical groups p.value = 0.580, p.value = 192, p.value = 456 respectively, where all of them had low lymphocyte count. The means of lactate dehydrogenase, ferritin, and D-dimer a showed a highly significant increase in Covid-19 patients when compared to the control group, p.value = 0.000, p.value = 0.000, p.value = 0.000 respectively. The results showed a highly significant increase in BUN in COVID-19 patient when compared with control group, p.value = 0.001, but the creatinine doesn't show any significant differences in COVID-19 patient when compared with control group, p.value = 0.405. Lactate dehydrogenase showed highly significant increase in critical group when compared with moderate group, p.value = 0.004, and showed significant differences in severe group when compared with moderate group, p.value = 0.031, but did not show significant differences between severe and critical groups, p.value = 0.690. Ferritin and D-dimer showed highly significant increase in critical group when compared with moderate group, p.value = 0.009, p.value = 0.000 respectively, and severe group, p.value = 0.002, p.value = 0.000 respectively. While, showed no nay significant differences between severe and moderate groups, p.value = 0.579, p.value = 0.075 respectively. Urea showed highly significant increase in critical group when compared with sever group and moderate group, p.value = 0.000. Creatinine showed significant increase in critical group when compared with sever group and moderate group, p.value = 0.031, p.value = 0.034 respectively. Both urea and creatinine showed no significant differences between severe and moderate groups p.value = 0.747, p.value = 0.958 respectively. Conclusions: In COVID- 19 patients, lymphopenia is a prognostic factor, increase levels of acute phase protein lactate dehydrogenase, D-dimer, and ferritin associated with disease severity, and the blood urea nitrogen and serum creatinine among critical group were associated with disease severity. [ABSTRACT FROM AUTHOR]

The current study aims to measurement of some physiological parameter and biochemistry such as Hemoglobin (Hb), Platelets count (PT), White Blood Cells count (WBCs), Ferritin (Fe), Phosphorus and parameters of kidney functions are Urea and Creatinine, then compared the results with healthy people. The results showed that there was a significant decrease (P<0.05) in the values of Hb and PT compared to the healthy people and non-significant difference (P>0.05) was showed in WBC account in patients with chronic renal failure, there was a significant increase (P<0.05) in concentrations of ferritin, phosphorous, urea and creatinine when compared with healthy people. It was concluded that there is a relationship between the kidney defect that occurs in patients with kidney failure and some physiological and biochemical parameters such as: Hemoglobin, platelets, WBCs, ferritin, phosphorus creatinine and urea levels, where levels change significantly compared with the control group. Elevated ferritin isn't an indicator of iron execessive; it may represent the presence of inflammation. This leads to serious complications, so they must be controlled and patients should be given appropriate medications [ABSTRACT FROM AUTHOR]

Determination of inflammatory biomarkers in sera of rats with renal tubulointerstitial fibrosis and evaluated the relation them with erythropoietin deficiency which causes anemia. Blood and histological samples collected from 80 male rats of albino BALB/c classified to sixty rats that were orally received with adenine at a concentration of 100 mg/kg to induce renal tubulointerstitial fibrosis, twenty rats as a control group. A highly significant increase in the serum levels of urea, creatinine, ferritin and Interleukin-6 and a highly significant decrease in blood hemoglobin and serum erythropoietin hormone in male rats with tubulointerstitial fibrosis compared with a control group (p<0.01). There was a strong negative relationship between the levels of erythropoietin with Interleukin-6, a strong positive relationship between the levels of erythropoietin with hemoglobin, while a moderate negative relationship for urea and creatinine in male rats with renal tubulointerstitial fibrosis. Significantly elevated ferritin and Interleukin-6 as a marker of inflammation associated with renal inflammation tubulointerstitial that causes complications to renal tubulointerstitial fibrosis, chronic renal disease and erythropoietin deficiency. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the level of hepcidin, ferritin and, iron among patients with beta - thalassemia the Diyala governorate. The study included collecting of 96 blood samples from both sexes and the samples were divided into 50 samples for beta -thalassemia patients. Their ages ranged between 10-25 years. The samples were collected from the thalassemia center in Baquba general teaching hospital, and 46 blood samples of healthy people were collected as a control group, their, ages ranged between (15-25) years, during the period from the beginning of November2020 to the end of December 2020. The results of the study showed a significant increase in hepcidin level of the patients ,group, which amounted to 1428.839 ± 715.150 ng/ml compared with the healthy group, which was 443.142 ± 290.595 ng/ml, as well as a significant increase in ferritin level of the patients, group 377.190 ± 139.870 ng/ml compared with healthy group 185.891 ± 135.652 ng/ml, a significant increase in iron concentration in patients 37.517 ± 10.207 µmol/L compared to healthy group 18.645 ± 5.845 µmol/L, in addition to a significant increase in the level of liver enzymes activity. It can be concluded that the significant increase in the levels of the studied biomarkers may be due to some diseases such as heart and liver diseases, also kidney failure diseases that are one of the characteristics of beta- thalassemia patients. [ABSTRACT FROM AUTHOR]

In the present study, the γ-Fe2O3 nanoparticles were prepared by using Ferritin solution via drop casting followed by annealing at 500°C for one hour in muffle furnace. The X-Ray diffraction (XRD) and Ultra Violet-Visible (UV-VIS) spectroscopy were carried out for phase identification and optical characterization. The γ- Fe2O3 phase was confirmed from the XRD analysis and the average crystallite size varied from approximately 19 to 24 nm calculated using Scherrer's formula.. The UV-VIS spectroscopy study implies dual band system with direct allowed band transitions at two values 2.21 and 2.58 eV using Tauc's relation. We compared two analysis schemes where, in one, the extrapolation of slope is used to find the band gap and in another singularity at Eg = hν identifies the band gap. In some systems, where, the dispersion in particle size smear the band edge; it is often difficult to find change of slope which causes ambiguity in determination of band gap. On the contrary, singularity approach eliminates the ambiguity in the analysis. [ABSTRACT FROM AUTHOR]

β-Thalassemia major is a hematologic disorder, which results from a defect in β-globin gene expression. Blood transfusions are very important in order to survival patients at the same time that causes increase iron over load. Our present study interested with the investigation of some hormonal and hematological parameters, effect on fertility in female patients with thalassemia major. The result shows a significant decrease (P≤0.05) in their levels of RBCs, HGB and MCV in non-splenectomized (non-SP) and splenectomized (SP) groups compared to control group, with significant increase (P≤0.05) in serum iron and ferritin in both non-SP and SP groups. In addition, significant increase (P≤0.05) in WBC of splenectomized (SP) groups compared to control, while HCT showed significant decrease (P≤0.05) in both (non-SP) and (SP), PLT significant increase (P≤0.05) only in SP groups compared to control. Significant decrease (P≤0.05) in BMI and age in non-SP group while, fertility hormone (AMH) decrease (P≤0.05) significantly in both non-SP and SP groups. Hematological study showed many morphological disorders such as target cell, nucleated erythrocytes and hypochromic. Conclusion from the study that accumulation of iron and ferritin lead to oxidative stress and damage for many organs like pituitary-hypothalamic and "gonads" axis that causes amenorrhea, delay sexual development and infertility with sexual dysfunction due to hypogonadism. Early diagnosis with regular follow and treatment very important for normal sexual development, improve life and reduce the complications. [ABSTRACT FROM AUTHOR]

We have analyzed the magnetization data of antiferromagnetic ferritin particles. Ferritin is an ideal superparamagnetic system with lower bifurcation temperature Tbf (≈ 15.2 to 18.2 K). Therefore, the magnetization data as a function of applied magnetic field (up to 50 kOe) are measured at 150 K. The data are investigated considering the presence of magnetic anisotropy. The estimated value of magnetic anisotropy constant for ferritin is found to be ≈ 104 J/m3. This value of magnetic anisotropy constant is also verified by Néel relaxation theory. The results indicates that this method is helpful for estimation of magnetic anisotropy constant of magnetic nanoparticle systems. [ABSTRACT FROM AUTHOR]

Beta thalassemia is a hereditary hemolytic anemia caused by a defect in the ability of erythroblasts to synthesize the β chain of hemoglobin. The aims of the current study were to investigate the diagnostic value of serum Osteoprotegerin in B-TM patients, and assay as an early biomarker for osteoporosis. Methods: This cross-sectional study was conducted at Thalassemia Center at Al-Zahraa Teaching Hospital in Al–Najaf province, Iraq, in the period from January 2018 to July 2018. this study was conducted with eighty-eight of males that age ranges from 2-29 years, which divided in 60 of males with β-thalassemia and 28 voluntary healthy as a control groups. Assay of study estimation of parameters level that include: iron and Hb; osteoprotgrin, vitamin D3, ferritin, Hepcidin and Transferrin measurement by using sold phase enzyme linked immune sorbent assay. It also investigates the relationship between these biomarkers levels, and, Body Mass Index, and splenic status. Results: The results reported a significant (P<0.05) decreased in Hb, body mass index, Hepcidin and vitamin D3 hormone, while serum iron, ferritin levels, Transferrin exhibited a significant (P<0.05) increases in β-thalassemic patients as comparison with healthy groups. ELISA assay of serum Osteoprotegerin (OPG) revealed significantly higher levels for thalassemia patients than healthy controls. Of particular interest is the obvious positive correlation between OPG levels transferrin and negative correlation with serum vitamin D3. Conclusion: The current study concluded that a Osteoprotegrin is some diagnostic markers for B-thalassemia associated negatively with decrement in Vit D level. [ABSTRACT FROM AUTHOR]

The goal of the present study is to demonstrate the use of potentiometric titration for investigation of some processes of iron homeostasis, namely the influence of UV on iron release from the ferritin molecule. The ferritin iron is used as a marker for different cancer diseases, especially for skin cancer. Therefore, it is important to investigate the effect of UV on ferritin release of iron. Ferritin is an iron-storing protein that plays an essential role in the biochemical reactions and the iron transport of all living organisms. The iron is stored within the ferritin core in the form of insoluble crystals containing Fe(III). Therefore, for its release, the mineral matrix has to be decomposed, usually through a reduction of Fe(III) to Fe(II). Our study considers the action of UV radiation on the structure of the protein molecule. Eventual changes in the ferritin conformation under the irradiation could result in the change of channel forming regions responsible for the iron release. This can be assessed by the quantity of Fe (II) obtained in a subsequent mobilization procedure evoked by exogenous reducing agents. In our case the content of the reduced iron is determined by the method of potentiometric titration. As already was shown, this method promises to become highly useful for quantitative evaluation of released Fe2+ [ABSTRACT FROM AUTHOR]

The regulation of iron in a living organism is extremely important as it can have lethal damage to the organism. Ferritin is an iron-storing protein that plays an essential role in the biochemical reactions and the iron transport of all living organisms. As such, the ferritin can play a key role in diagnosing neurodegenerative and cancer diseases by detecting low quantities of iron. The reason for the study is based on the increased number of skin diseases due to the influence of UV radiation. We study the adsorption properties of the protein Ferritin on a gold surface after UV irradiation using Variable Angle Spectroscopic Ellipsometry (VASE) in situ. Special equipment for irradiation of samples with UV (405 nm) was made. The results obtained show that with increasing irradiation time, the initial thickness of the ferritin proteins decreases, resulting either in an increase in molecular density when iron ions are released or in the deformation of the ferritin proteins. The data show that the methods are applicable for analysis and characterization of adsorption of biomolecules. [ABSTRACT FROM AUTHOR]

Human brain tissue samples were analyzed by energy dispersive X-ray fluorescence technique. Ten specimens were obtained from six male donors of age between 38 and 72 years. Lyophilized tissues were mechanically crushed into a powder form and pressed into pellets. Elemental analysis performed using Amptek Experimenter's XRF Kit identified the following elements: Al, P, S, Cl, K, Ca, Cr, Fe, Ni, Cu, Zn and As. The most abundant elements were P, S, Ca, Fe, and K. Some dependence of an element abundance on the age of a donor was observed for K (decreasing tendency with age) and for Ca and Zn (increasing tendency with age). XRF results were complemented and compared with Mössbauer spectroscopy measurements performed at room temperature (~ 300 K). Mössbauer spectra were collected in transmission mode employing 57Co source embedded in a rhodium matrix. Applied evaluation procedure of spectra disclosed the presence of the trivalent ferritin-like iron, specifically ferrihydrite and hematite in molecule of ferritin in the form of small particles exhibiting superparamagnetic behavior. Relatively high linewidths values point at a distribution of environments with respect to electron density and/or a presence of another non-magnetic component. Anticipated correlation between the effect of Mössbauer spectra and iron content derived from XRF spectra analysis was confirmed. [ABSTRACT FROM AUTHOR]

Human liver ferritin and its pharmaceutical analogue, Ferrum Lek, containing nanosized hydrous ferric oxides cores in the forms of ferrihydrite and akaganéite, respectively, were studied using Mössbauer spectroscopy with a high velocity resolution in the temperature range of 295-90 K. To simplify comparison, these spectra were fitted using one quadrupole doublet within the homogeneous iron core model. An unusual line broadening with a temperature decrease was observed in this way for human liver ferritin below ~150 K and for Ferrum Lek below ~130 K. Some anomalies were also observed below these temperatures for spectral area and quadrupole splitting. The Debye temperature for both iron cores was evaluated from temperature dependence of isomer shift using the temperature dependence of the secondorder Doppler shift. [ABSTRACT FROM AUTHOR]

Ferritin is an iron-storage protein in most living systems with a cage-like structure. It has inherent property to form metallic nanocore within its cavity. The metallic core formed within the Archaeoglobus fulgidus ferritin cavity is stabilized by modulating the protein structure by site directed mutagenesis. Encapsulation protocol of various metals within the engineered ferritin cage (AfFtn-AA) is optimized. Dense metallic cores are visualized using electron microscopy and the bound metal was quantified by ICP-spectrometry. The AfFtn-AA is loaded with up to about 350 cobalt, 2000 chromium, and as high as 7000 iron atoms, separately. The metal-protein nanocomposites formed by encapsulation of cobalt, chromium, and iron are studied. Magnetic resonance imaging of the agarose embedded nanocomposites shows brightening of T1-weighted images and signal loss of T2-weighted images with increasing concentration of the nanocomposites. Shortening of magnetic relaxation times in the presence of the nanocomposites confirm their ability to enhance magnetic relaxation rate and suggests that the nanocomposites have potential application as MRI contrast agent. [ABSTRACT FROM AUTHOR]

Ferritins are the metalloproteides present in plant and animal cells. Their micelleous tertiary structure allows iron accumulation in the form of hydratated oxides and phosphates. Thus, ferritin is a large spherical macromolecular protein with iron compounds in the cavity created by a peptide shell. Because of the spherical shape, ferritin macromolecule should not manifest magnetic anisotropy; however, in solution it shows the induced magnetic birefringence (Cotton-Mouton effect) and changes in intensity of the scattered light components. Therefore, the Cotton-Mouton effect, Rayleigh light scattering and nonlinear light scattering in dc magnetic field, were measured at room temperature for 100 mM NaCl solutions of apoferritin/ferritin loaded with different contents of Fe atoms/molecule. Analysis of the results has shown that the deformation of linear optical polarizability induced in the ferritin by a magnetic field and the orientation of the induced and permanent magnetic dipole moment by this field are the main sources of the magneto-optical phenomena observed. The results suggest the simultaneous diamagnetic and superparamagnetic behavior of the ferritin biomacromolecule. [ABSTRACT FROM AUTHOR]

Ferritins are protein nanocages that use iron and oxygen chemistry to concentrate iron and trap dioxygen or hydrogen peroxide in biominerals of hydrated ferric oxides, 5–8 nm in diameter, inside the cages. The proteins are found in nature from archea to humans. Protein catalytic sites are embedded in the protein cage and initiate mineralization by oxido-reduction of ferrous ions and dioxygen or hydrogen peroxide to couple two iron ions through a peroxo bridge, followed by decay to diferric oxo/hydroxyl mineral precursors; ferritin protein subdomains that fold/unfold independently of the protein cage control recovery of ferrous ions from the mineral. Early EXAFS (1978) was extremely useful in defining the ferritin mineral. More recent use of rapid freeze quench (RFQ) EXAFS spectroscopies, coupled with RFQ Mössbauer, Resonance Raman and rapid mixing UV-vis spectroscopy, have identified and characterized unusual ferritin protein catalytic intermediates and mineral precursors. EXAFS spectroscopy can play an important role in the future understanding of protein catalysis in metalloproteins such as ferritin, ribonucleotide reductase and methane monooxygenases. Needed are instrumentation improvements that will provide rapid-scan fluorescence spectra with high signal/noise ratios. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Recent technological improvements allow the method of in vivo XRF to provide useful sensibility for diagnostics or monitoring in biomedical applications. In cases of hereditary sanguine disorders as the β-thalassaemia or a genetic disorder like Haemochromatosis, there is a high concentration of elements as Fe, Zn and Cu in the skin and internal organs, due to the treatment of those abnormalities or due to the own dysfunction caused by the disease. The levels of Fe related to the patient bearers of the β-thalassaemia are determined, at the moment, measuring a protein in the sanguine current, called ferritin. The monitoring of the protein is ineffective in several situations, such as when the patient suffers any disturbance of health. Nowadays, the main forms of measuring the levels of those metals through hepatic storage are the biopsy of the liver, that is invasive and potentially dangerous, presenting a rate of mortality of 0.1%, and by means of magnetic susceptibilities that employs a quantum superconductor, which is highly expensive and there are only three main world centers with this equipment This work investigates the use of a Si PIN-diode detector and a 238Pu source (13 and 17keV; 13%; 95.2mCi; 86y) for the measurement of Fe skin levels compatible with those associated to the disease β-thalassaemia. XRF spectra were analyzed using a set of AXIL-WinQXAS programs elaborated and disseminated by the IAEA. The determination coefficient of the calibration model (sensitivity curve) was 0.97. Measurements on skin phantoms containing concentrations of Fe in the range from 10 to 150 parts per million (ppm), indicate that we are able to detect Fe at levels of the order of 15ppm, using monitoring periods of 50 seconds and skin entrance dose less than 10 mSv, The literature reports skin Fe levels from 15.0 to 60.0 ppm in normal persons and from 70 to 150 ppm in thalassaemics patients. So, the employed methodology allows the measurement of the skin Fe concentration. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Ferritin is a multimeric protein that stores 30% of human body iron as oxidised crystalline ferric phosphate, mainly in liver and heart muscle and in haemopoetic tissue and endothelium. Ascorbate causes iron release from ferritin by reducing stored iron (Km= 2 mM). Raised concentrations of non-protein bound iron catalyse formation extracellular and intracellular reactive oxygen species (1). Since intracellular and extracellular concentrations of ascorbate are generally within the range 40-250μM, this process is considered unlikely to contribute to pathological oxidation reactions. Only when ascorbate is raised > 2mM by i.v. injection is it deemed to be pro-oxidant (2). However, we have observed that ascorbate-dependent ferrous iron loss from horse spleen ferritin 50 nM (Sigma-Aldrich, UK), monitored for 2-3 h using a plate reader at 24°C to detect changes in absorption of ferrozine at 562μm (pH 7.0 buffered with sodium citrate 10 mM; MOPS 50 mM and 75μM ferrozine) is synergized by ferrous iron > 2 μM). Raising Fe(II) from 0 to 10μM decreases the Km of ascorbate-dependent Fe(II) release to 185±10μM (P< 0.001) and increases the Vmax of release 5-fold from 11.4±0.2 to 60±2.0 nmol Fe(II) mg-1ferritin min-1 (P < 0.001). In the absence of external iron, hydrogen peroxide acts as a potent non-competitive inhibitor of Vmax of ascorbate-dependent iron release by promoting two electron Fe(II) oxidation within ferritin( I.C50111 ±34 μM). The IC50 of H2O2 on the apparent Km of ascorbate-dependent Fe(II) release is 352±92μM; addition of 10 μM Fe(II) with superoxide dismutase (50 units ml-1) reduces the IC50 to H2O2 30±42μM (P < 0.01) without altering the Vmax of Fe(II) release. Thus, H2O2 changes from a non-competitive inhibitor of ascorbate dependent of Fe(II) release in the absence of external Fe(II) to a competitive inhibitor when Fe(II) is present. These results suggest that single electron reactions generated by iron-ascorbate interaction, possibly resulting from ascorbyl and ferryl radical are a potent means of iron reduction and release from ferritin (3,4) and that this release mode differs from that caused by ascorbate alone, which may reduce bound di-Fe(III) at the ferroxidase centre by a bidentate two-electron reduction. Our novel finding that ascorbate and iron synergistically exacerbate iron release from ferritin has many implications relating to inflammatory mechanisms, the most immediate provides a rationale for iron-chelation therapy of arthritis and atherosclerosis, where iron and ascorbate and H2O2 released from necrotic macrophages and endothelium provide essential substrates for Fenton-Haber-Weiss reactions continuously generating superoxide and · OH radicals (5). [ABSTRACT FROM AUTHOR]

An abstract of the article "Kinetics and chemiluminescence studies of ferritin iron mobilization by ascorbate" by C. Badu-Boateng, B. McNamara and R.J. Naftalin is presented.

The kinetics of ferritin and albumin adsorption on gold (Au) surface is studied with electrochemical (impedance spectroscopy and cyclic voltammetry) and optical (ellipsometry) methods. The obtained results enable modelling of the protein adsorption on blood vessels and tissues in pathological processes. The kinetics of protein adsorption could be implemented in medical applications and in developing new biosensors systems. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The obtained values during the period when the plant has finished its vegetative growth display good relations with yield. Today the study of leaf fluorescence signature via imaging techniques, in order to estimate the multi-stress tolerance in plants is applying successfully. Duilio cultivar resulted more tolerant to high temperature stress, showing a good degree of adaptation to Albanian environmental conditions. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]