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The objective of the work was to determine the content of magnesium in plants of Trifolium pratense L. which grew in an environment contaminated with aluminium or copper. The growth and development of the plants was carried out in hydroponics, with strictly controlled composition and pH of the growth medium. Copper was added to the medium (as an additional application) in a solution of CuSO4·5H2O, and aluminium in the form of a solution of AlCl3, at concentrations of Al+3 and Cu+2 of 20 and 100 mg dm-3. The concentration of magnesium, aluminium and cooper was determined by means of a ICP sequential emission spectrometer D-820 Hilger Analytical (UK) in extracts from the roots and aboveground parts. Decreasing pH of the medium did not cause any statistically significant changes in the concentration of the metals studied. There was a significant increase in the concentration of aluminium and copper in roots and aboveground parts of Trifolium pratense L. and lower magnesium concentration for plants that were grown in an environment contaminated with Al+3/ Cu+2 at a concentration of 100 mg dm-3. In the lower concentrations of both stressors (20 mg dm-3) a decrease was noted in the level of magnesium in the whole plant, and a statistically significant increase in the concentration of aluminium and copper in the roots of Trifolium pretense L. In the aboveground parts of the plants that grew in me-dium supplemented with 20 mg dm-3 of Al+3/Cu+2, the increase of the concentration of these metals was not statistically significant.
River-lake systems comprise chains of lakes connected by rivers and streams that flow into and out of them. The contact zone between a lake and a river can act as a barrier, where inflowing matter is accumulated and transformed. Magnesium and calcium are natural components of surface water, and their concentrations can be shaped by various factors, mostly the geological structure of a catchment area, soil class and type, plant cover, weather conditions (precipitation- evaporation, seasonal variations), land relief, type and intensity of water supply (surface runoffs and groundwater inflows), etc. The aim of this study was to analyze the influence of a river-lake system on magnesium and calcium concentrations in surface water (inflows, lake, outflow) and their accumulation in bottom deposits. The study was performed between March 2011 and May 2014 in a river-lake system comprising Lake Symsar with inflows, lying in the Olsztyn Lakeland region. The study revealed that calcium and magnesium were retained in the water column and the bottom deposits of the lake at 12.75 t Mg year-1 and 1.97 t Ca year-1. On average, 12.7±1.2 g of calcium and 1.77±0.9 g of magnesium accumulated in 1 kg of bottom deposits in Lake Symsar. The river-lake system, which received pollutants from an agricultural catchment, influenced the Ca2+ and Mg2+ concentrations in the water and the bottom deposits of Lake Symsar. The Tolknicka Struga drainage canal, to which incompletely treated municipal wastewater was discharged, also affected Ca2+ and Mg2+ levels, thus indicating the significant influence of anthropogenic factors.
The objective of this study was to investigate magnesium concentrations and load, and to determine their seasonal changes in runoff water from catchments classified as nitrate vulnerable zones. The results indicate that the average concentrations of 12.2 mg Mg⋅dm-3, with fluctuations within the range of 3.3 to 26.2 mg⋅dm-3, and average annual load of 14.3 kg Mg⋅ha-1⋅year-1, with fluctuations within the range of 4.8 to 41.6 kg Mg⋅ha-1⋅year-1, in runoff water from agricultural areas are determined by weather conditions (season), type of drainage system (ditches, drains) and fertilization intensity. In comparison with land drained by a network of drainage ditches, intensive farming in drained areas increases magnesium loss 2.5-fold from 10 kg per hectare of semi-intensively farmed area to 25 kg Mg⋅ha-1 in an intensively farmed area. The highest magnesium loss was reported in the non-growing season, and around 46% of total magnesium load was leached out in the winter. The magnesium loss was minimized during harsh winters and summer draughts (to around 1.2 kg Mg⋅ha-1⋅year-1) due to a seasonal absence of runoffs.
The aim of this work was to trace differences in magnesium and calcium concentrations (both total and ionic form) between goats which were in late pregnancy and lactating goats. The study involved 30 goats. Blood samples were taken three times from each goat. Total concentrations of magnesium and calcium were determined with the colorimetric method and (A — 1.581 mmol dm-3; B — 2.052 mmol dm-3; C — 2.112 mmol dm-3). Ionic form of calcium based on using ion—selective analysis (A — 1.219 mmol dm-3; B — 1.126 mmol dm-3; C — 1.123 mmol dm-3). The study showed that mean value of both the total of calcium from each goat did not reach the reference level for this species. Ionic form of calcium was within the lever limit of the physiological norm. The content of magnesium in all the groups was within the range of reference concentrations (A — 1.051 mmol dm-3; B — 1.165 mmol dm-3; C — 1.117 mmol dm-3).
The objective of the study has been to determine magnesium concentrations and their seasonal changes in waters of re-naturised reservoirs situated in a rural area, 25 years after their re-creation. The study included 3 small, non-flow-through reservoirs, situated close to the village of Setal, in the commune of Dywity. Water samples for analysis were collected once a month in 2005 and 2006. They were examined in respect of the magnesium level and such physicochemical parameters as temperature, pH, oxygenation, dissolved oxygen, electrolyte conduction and water depth. The results prove that the environment of the surface waters in this area is poor in magnesium (5.2 mg⋅dm-3 - 6.6 mg⋅dm-3 on average), which is characteristic for postglacial regions. The re-created water reservoirs can be listed in water quality class I in terms of their magnesium content. The waters of these small re-created lakes were characterised by huge seasonal changes of magnesium concentrations. However, the fluctuations of Mg+2 concentrations were often larger within particular sites than between the examined reservoirs. The highest average seasonal magnesium concentration of 6.6 mg.dm-3, varying from 3.9 mg⋅dm-3 to 10.0 mg⋅dm-3, was determined in the waters of a reservoir whose whole catchment had for many years been used for agriculture. The lowest magnesium concentrations in the waters of the reservoirs occurred in springtime, with a slight increase in early summer and an equally slight decline afterwards. No significant increase in magnesium amounts was found until autumn, before they reached their peaks in wintertime. Such a course of fluctuations was caused by the maximum magnesium biosorption in spring and releasing internal reserves (green matter and bottom deposits) of the reservoirs in autumn and winter. Decrease and increase in the Mg+2 ion concentration in the waters of the reservoirs occurred in two ‘pulses’: in the springtime and wintertime, respectively.
The study was performed on pregnant ewes and their progeny. The experimental group of ewes was given injections of 5 mg selenium in the form of sodium selenite. The sodium selenite s.c. injections resulted in monre than a triple, significant increase in the selenium level in ewes, at the first month as compared to the initial concentration of 0.42±0.11 to 1.38±0.21 μmol/l. Also in lambs a marked increase in selenium was noticed in the first and fifth weeks of life, but the levels of this element were by a half lower than in their mothers. Moreover, considerable diminution of magnesium concentration was observed in both groups: from 1.05±0.05 to 0.82±0.07 mmol/l in Group 1 of ewes in the second month following Na₂SeO₃ injection, and from 0.94±0.05 to 0.82±0.08 mmol/l in lambs, in the ninth week.
Digestive system neoplasms pose a serious health problem both in Poland and abroad. Neoplasms are frequently considered to be caused by impaired homeostasis in the human body. Development of neoplasms may be linked to disturbances in concentration of elements, including magnesium as a major intracellular cation. The objective of this study was to evaluate the concentration of magnesium in plasma and tissue samples taken from patients suffering from neoplasms of the stomach or the large intestine. The study involved 35 patients, including 20 affected by stomach cancer and 15 suffering from large intestine cancer. The patients were in the age rage of 36-77. The material included blood samples taken from patients before and seven days after surgery, as well as samples of cancerous and healthy tissues. The colorimetric method with a Genesis spectrophotometer was used for determination of magnesium concentration. A statistically significant difference was observed between plasma magnesium concentration in patients affected by stomach cancer and the normal range. Elevated values of magnesium concentration measured on the seventh day after the procedure as compared to the concentration before the procedure was noted, however, the difference was statistically insignificant. No significant differences were observed in magnesium concentration measured before and after the procedure, or in comparison to the normal range in patients with large intestine cancer. Determination of tissue magnesium showed that magnesium concentration was higher in cancerous than in healthy tissue. Obtained results demonstrate that magnesium homeostasis is impaired in patients, which may be important in the pathoghenesis of digestive system neoplasms.
Bone fractures, especially when treated surgically, are connected with changes in the homeostasis of the elements of which bone compounds consist, as well as the ones which participate in controlling processes. Such changes influence both the fracture itself and the operative procedure. For successful treatment of broken bones, it can be crucial to bring the homeostasis of bioelements back to the normal state. Thus, the aim of this work has been to determine magnesium and calcium concentrations in plasma from patients with fractures of long bones, and to analyze changes in the examined elements depending on the time after the operative procedure, injury and patient’s age. The research was conducted on the blood of patients: 1) with long bone fractures treated surgically, 2) after a limb amputation because of a fracture or injury, 3) with long bone fractures and with multiorgan injury. With respect to the patients’ age, there were 3 groups: 1) patients aged 18-40 years, 2) patients aged 41-60 years, 3) patients older than 60 years. In the postoperative period, the patients were on a strict postoperative diet, receiving only i.v. 0.9% NaCl and 5% glucose solutions. Blood was taken from patients first directly after admittance to hospital and next on the first, third, fifth and seventh day after an operative procedure. Plasma calcium and magnesium concentrations were determined by the method of emission spectrometry with induction plasma (ICP-OES). The results were worked out statistically. The differences p<0.05 were taken into consideration as statistically significant. The research showed that in the blood plasma from patients with long bone fractures treated surgically, there were noticeable decreases of calcium and magnesium concentrations mainly on the first, third and fifth postoperative day. These changes depended on the extend of an operative procedure, but did not depend on the patients’ age. However, with respect to magnesium, its statistically significant decrease was noticed in the group of oldest patients. In the postoperative period, it is especially important to pay attention to calcium and magnesium concentrations, and for patients over 60 years of age magnesium supplementation is necessary. Maintenance of macronutrient homeostasis in an organism can be crucial for the patient’s convalescence process.
In literature of the recent years, more and more attention has been paid to the correlations between magnesium and blood lipids. Lipid balance disorders induced by hypomagnesaemia bring about changes in the liquidity of cellular membranes. Increased migration of lipids, in particular of VLDL and LDL, across arterial walls has been observed in hypomagnesaemia, with their consequential deposition in the internal membrane. Kidneys, apart from urine production and elimination, fulfil many other important functions in organism. They determine normal functioning of the whole organism, while disorders in their function lead to serious changes in homeostasis. Lipid balance disorders are a serious risk factor in the development of atherosclerotic lesions in patients with chronic kidney failure. The aim of this study was to examine the correlations between magnesium concentration and total cholesterol and HDL- and LDL-cholesterol contents in women and men with chronic kidney failure under and over 50 years of age. Subjects were divided into four groups: K1 – 14 women 34-50 years old, K2 – 14 women over 50 years old, M1 – 17 men 30-50 years old, and M2 – 13 men over 50 years old. Tests were made using a COBAS INTEGRA analyser. High concentration of Mg, exceeding the upper limit of reference values, was observed both in two women and men groups (K1 – 1.26 mmol(+) kg–1; K2 – 1.25 mmol(+) kg–1; M1 – 1.13 mmol(+) kg–1; M2 – 1.16 mmol(+) kg–1). Also the levels of total and HDL-cholesterol in all subjects were within physiological limits (respectively: K1 – 4.61 and 1.23 mmol(+) kg–1; K2 – 4.69 and 1.29 mmol(+) kg–1; M1 –3.94 and 1.20 mmol(+) kg–1; M2 – 3.98 and 1.16 mmol(+) kg–1). Only the LDL-cholesterol concentration in the group of younger men was below normal limit (1.93 mmol(+) kg–1). Small positive correlations were obtained between Mg content and that of total and LDL-cholesterol in older women and younger men groups as well as between Mg and HDL-cholesterol contents in both men groups. At the same time, a small negative correlation was obtained between Mg and LDL-cholesterol concentrations in the older men group. These correlations were statistically non-significant.
A high yield of oilseed rape can be achieved provided an adequate supply of magnesium and sulfur in critical stages of yield formation. The magnesium status in canopy was studied in the 2008, 2009 and 2010 growing seasons. A one factorial experiment consisting of six treatments, set up to verify the research hypothesis, was as follows: control (C), NP, NPK, NPK+ MgS - 1/3 of total planned dose applied in spring (NPKMgS1), NPK+1.0 MgS dose in autumn (NPKMgMgS2), NPK+MgS - 2/3 in autumn + 1/3 in spring (NPKMgS3). Plant samples were taken at three stages: rosette (BBCH 30), the onset of flowering (BBCH 61) and maturity (BBCH 89). An entire sample was partitioned in accordance with the growth stage into main plant organs: leaves, stems, straw and seeds. The yield of biomass, magnesium concentration and its content was determined in each part of the plant. The magnesium concentration in leaves at the onset of flowering can be used as the first predictor of yield. The predictive strength of the magnesium content in seeds as the final yield predictor corroborated the hypothesis of the importance of magnesium for the seed sink build-up. An analysis of relationships between the magnesium content in plant parts during the growing season and yield of seeds can be used to make an ex-post analysis of factors disturbing the development of yield structural components. The main cause of yield reduction in 2009 as compared to 2008 was the insufficient supply of magnesium to vegetative organs of oilseed plants since the onset of flowering. It was documented that the degree of magnesium supply to a growing silique is critical for the seed yield performance, as noted in 2008. It was also found that any disturbance in the magnesium supply to oilseed rape since the onset of flowering led to reduction in the seed density, which in turn decreased the magnesium seed sink capacity, as the study clearly demonstrated.
The Premenstrual Syndrome (PMS) is described as a cyclical disorder related to the hormonal changes during a menstrual cycle, which affects the emotional and physical health of many women during their reproductive period of life. The PMS can obviously change the quality of life. The syndrome is characterized by a complex group of symptoms, such as depression, irritability, mood swings, anxiety, abdominal discomfort. These signs occur during the luteal phase of a menstrual cycle and disappear after the onset of menses. Some studies suggest that a variety of nutrients may play an important role in the mood swings which occur cyclically during the course of the premenstrual syndrome and that some can have a beneficial impact, especially on the estrous phase of a menstrual cycle. The aim of the paper is to review the results of some studies concerning the role of bioelements in patients with the PMS. Concentrations of magnesium, zinc, selenium and manganese are the highest during menses and the lowest in the ovulatory phase. Fluctuations of the magnesium concentration during a menstrual cycle and the involvement of this element in many cellular pathways and neuromuscular activities obviously affect the incidence or intensity of the PMS symptoms. However, we lack firm evidence that magnesium supplementation can have a positive effect on alleviating the the PMSrelated ailments. Some relationship between the PMS and bone demineralization or depressed calcium concentration in blood has been identified. However, further studies are necessary to examine how the calcium concentration in a human body can decrease the intensity of the PMS symptoms.
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