Mineral supplementation of white wheat flour is necessary to maintain adequate mineral status and bone characteristics in rats

This experiment was designed to compare the effect of ingestion of a wheat flours on mineral status and bone characteristics in rats. White flour was tested either without further mineral supplementation or with Mg, Fe, Zn and Cu supplementation. The flour diets were compared to a control purified diet. Four groups of 10 male Wistar rats each were fed one of the experimental diets for 6 wk and mineral status and tissue retention as well as bone characteristics were determined. As expected, mineral intake, except for calcium, was significantly lesser in rats fed the white flour diet than in the other groups. The rats fed the white flour diet had the lowest food intake, weight gain, fecal excretion and intestinal fermentation. The most important result was that Mg and Fe status were drastically lower in rats fed the white flour diet than in those fed whole flour or control diets. The status of these both elements were significantly improved by the mineral supplementation of white flour. There were no major significant differences between mineral-supplemented white flour and whole flour groups in mineral status. Furthermore, bone mineral densities (total, metaphyseal and diphyseal) were significantly lower in rats fed white flour diet compared to the other diet groups, while no significant difference was observed between the mineral-supplemented white flour, whole flour or control diet groups. In conclusion, the present work shows clearly the importance of mineral-supplementation of white wheat flour to sustain an adequate intake of minerals. Our results indicate also that the whole wheat flour did not negatively alter mineral bioavailability, in comparison to mineral supplemented white flour. Clinical studies are still needed to confirm these rat results in human.     

Mineral Elements in the Hair of Amblyopic Children

Amblyopia is a common cause of vision damage in children, and some aspects of its etiology are not clear. A number of mineral elements have important effects on the nerve and visual nerve systems. However, little is known about the relationship between amblyopia and nutritional mineral elements. In this study, hair samples were collected from 67 children with amblyopia and 57 age-matched control groups. The height and weight of each child was measured, and body mass index (BMI) was calculated. Mineral elements were determined by atomic absorption spectrometry and inductively coupled plasma-atomic emission spectrometry. The calcium and magnesium levels in the hair of amblyopic children were higher (p?<?0.006), but the level of manganese were lower compared with those in the control groups (p?<?0.006). Other elements measured were found to have an insignificant difference between the two groups (p?>?0.006). The BMI of amblyopic children was higher (p?<?0.001). These results show that mineral elements may play an important role in the visual development of children. Therefore, studies should pay more attention to investigating the impact of mineral elements on child vision.     

Effects of oral aluminum on essential trace elements metabolism during pregnancy

The present study was conducted to assess in rats the effects of oral aluminum (Al) exposure on calcium (Ca), magnesium (Mg), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) accumulation and urinary excretion. Three groups of plug-positive Sprague-Dawley (SD) rats were given by gavage 0, 200, and 400 mg/kg/d of Al(OH)₃ on gestational days 1–20. Three groups of nonpregnant female SD rats of the same age received Al(OH)₃ by gavage at the same doses for 20 consecutive days. At the end of the treatment period, 24-h urine samples were collected for analysis of Al and essential elements. Subsequently, all animals were sacrificed and samples of liver, bone, spleen, kidneys, and brain were removed for metal analyses. With some exceptions, the urinary amounts of Al, Mn, and Cu excreted by pregnant animals as well as the urinary levels of Al excreted by nonpregnant rats were higher in the Al-treated groups than in the respective control groups. Although higher Al levels were found in the liver of pregnant rats, the concentrations of Al in the brain of these animals were lower than those found in the same tissues of nonpregnant rats. With regard to the essential elements, tissue accumulation was most affected in pregnant than in nonpregnant animals. In pregnant rats, the hepatic and renal concentrations of Ca, Mg, Mn, Cu, Zn, and Fe, as well as the levels of Ca in bone, and the concentrations of Cu in brain were significantly higher in the Al-exposed groups than in the control group. According to the current results, oral Al exposure during pregnancy can produce significant changes in the tissue distribution of a number of essential elements.     

Ultrastructural studies on paneth cell apoptosis in zinc deficient rats

Summary An ultrastructural study into the origins of the increased number of apoptotic bodies in the small intestinal crypts of zinc deficient rats was carried out. Two strains of rat were used and each strain was sub-divided into three groups; zinc deficient, pair-fed controls and ad libitum controls. All three groups of one strain were heavily infested with intestinal parasites, both bacteria and flagellated protozoa. Increased numbers of apoptotic bodies were found in the upper crypt/villus region of zinc deficient rats in both the parasitized and parasite free strains. Some of these apoptotic bodies contained structures resembling the electron lucent intestinal epithelial cells found in zinc deficient rats, others contained unidentifiable cell remnants that had undergone advanced degenerative changes. In zinc deficient parasitized rats only, apoptotic bodies were found at the crypt base which contained identifiable remnants of Paneth cells. The majority of these had been ingested by intestinal epithelial cells but some had been ingested by macrophages. The effect of zinc deficiency and parasitic infestation on apoptosis is discussed.J.G. Jones was supported by funds from the Welsh Scheme for the Development of Health and Social Research.     

熊果酸对酒精性骨质疏松大鼠骨形成、骨矿化的影响

目的：探讨熊果酸对酒精所致骨质疏松大鼠骨形成、骨矿化的影响。方法：雄性Wistar大鼠60只,按体重随机分为空白对照 组、熊果酸对照组、模型组、熊果酸低、中、高剂量组,同时分别给予生理盐水、150 mg/kg 熊果酸、50%酒精,50 mg/kg 熊果酸,100 mg/kg 熊果酸,150 mg/kg 熊果酸灌胃。熊果酸对照组生理盐水剂量同空白组,熊果酸低、中、高剂量组酒精剂量同模型组。灌胃共 持续8 周。磷钼酸法检测血清磷(P)含量,比色法检测血清钙(Ca)含量,酶联免疫吸附（ELISA）法检测血清骨钙素(BGP)、骨形成蛋 白-2(BMP-2)浓度;HE 染色法观察股骨结构的病理学变化。结果：与空白对照组相比较,模型组血清BGP、BMP-2 和Ca、P 均明显 降低,且有统计学差异(P < 0.05),但熊果酸对照与空白对照组各项指标结果相近。熊果酸中、高剂量组大鼠血清BGP、Ca 和P 水 平均较模型组有显著升高,差异具有统计学意义(P < 0.05),但仅熊果酸高剂量组血清BMP-2 显著升高(P < 0.05)。股骨组织HE 染色结果显示,空白对照组骨小梁致密、规则且较粗,粗细均匀;模型组骨小梁稀松、不规则、粗细不均匀,甚至可见骨小梁断裂; 熊果酸中、高剂量组骨小梁致密、规则、较厚、粗细均匀,未见骨小梁断裂。结论：熊果酸能够促进酒精性骨质疏松大鼠的骨形成, 抑制骨矿物质的流失,在改善酒精致骨质疏松方面有一定的保护作用。     

Effects of Aluminum Exposure on Bone Mineral Density,Mineral, and Trace Elements in Rats

The purpose of the study was to investigate the effects of aluminum (Al) exposure on bone mineral elements, trace elements, and bone mineral density (BMD) in rats. One hundred Wistar rats were divided randomly into two groups. Experimental rats were given drinking water containing aluminum chloride (AlCl₃, 430 mg Al³⁺/L), whereas control rats were given distilled water for up to 150 days. Ten rats were sacrificed in each group every 30 days. The levels of Al, calcium (Ca), phosphorus (P), magnesium (Mg), zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), selenium (Se), boron (B), and strontium (Sr) in bone and the BMD of femur were measured. Al-treated rats showed lower deposition of Ca, P, and Mg compared with control rats. Levels of trace elements (Zn, Fe, Cu, Mn, Se, B, and Sr) were significantly lower in the Al-treated group than in the control group from day 60, and the BMD of the femur metaphysis in the Al-treated group was significantly lower than in the control group on days 120 and 150. These findings indicate that long-term Al exposure reduces the levels of mineral and trace elements in bone. As a result, bone loss was induced (particularly in cancellous bone).     

Relationship between celandine isoquinoline alkaloids with macro- and microelements

Numerous linear and nonlinear correlations between the contents of alkaloids and mineral elements in the aerial parts and roots of greater celandine (Chelidonium majus L.) were revealed by means of correlation and regression analyses. These relationships became more significant with the transition from the sum of alkaloids to individual groups or fractions, which included compounds of similar compositions. The mathematical models describing the regulation of alkaloid metabolism by some mineral elements (Ba, Mg, Sr, Co, Cr, Zn, etc.) were developed in the analytical form. These models were tested in experiments with geochemical modeling using Zn.     

Relationship between Celandine Isoquinoline Alkaloids,Macroelements, and Microelements

Numerous linear and nonlinear correlations between the contents of alkaloids and mineral elements in the aerial parts and roots of greater celandine (Chelidonium majusL.) were revealed by means of correlation and regression analyses. These relationships became more significant with the transition from the sum of alkaloids to individual groups or fractions, which included compounds of similar compositions. Mathematical models describing the regulation of alkaloid metabolism by some mineral elements (Ba, Mg, Sr, Co, Cr, Zn, etc.) were developed in the analytical form. These models were tested in experiments with geochemical modeling using Zn.     

Assessment of hair mineral analysis commercially offered in Germany.

To evaluate intra- and inter-laboratory agreement concerning hair mineral analysis and interpretation of results, hair samples from 2 volunteers were sent to seven laboratories, which commercially offer hair mineral analysis in Germany. 6 weeks later, another identical part from the hair sample of volunteer 1 was sent to all seven labs. Altogether, 50 elements were analyzed, 23 by all seven labs. For comparability, only the results for these 23 elements were assessed. The intra-laboratory reproducibility was evaluated by the 2 identical hair samples from volunteer 1. On the average, the reproducibility seems to be sufficient (median +/- 9.48% to +/- 20.59%), but for individual elements there were unacceptable out-rulers up to 100%. Only one lab classified all elements of the first and the second analysis of the identical hair sample in the same category (below, within, or above normal range). The others grouped 4 to 7 elements different. This is not tolerable. The inter-laboratory comparability was assessed by the results of the hair samples of both volunteers. For the sample of volunteer 1 at least the results of 6 (out of 23) elements were within an acceptable range of +/- 30% from the consensus value (= mean of all seven labs). For volunteer 2 this was only the case for 2 (!) elements. Differences of more than 100% were found for most other elements. Moreover, in the vast majority of the tested elements there was no comparability of the cLassification to the respective reference ranges of the different laboratories. For example, for volunteer 1 only 3 elements (our of 23!) were identically classified by all seven labs. As neither the analytical results nor the classification to the individual reference ranges by the laboratories correspond in tolerable borders, conclusions, drawn from these results, cannot be valid. Hair mineral analysis from these laboratories is unreliable. Therefore we must recommend to refrain from using such analysis to assess individual nutritional status or suspected environmental exposure.     

Biofortification of crops with seven mineral elements often lacking in human diets – iron, zinc, copper, calcium, magnesium, selenium and iodine

The diets of over two-thirds of the world's population lack one or more essential mineral elements. This can be remedied through dietary diversification, mineral supplementation, food fortification, or increasing the concentrations and/or bioavailability of mineral elements in produce (biofortification). This article reviews aspects of soil science, plant physiology and genetics underpinning crop biofortification strategies, as well as agronomic and genetic approaches currently taken to biofortify food crops with the mineral elements most commonly lacking in human diets: iron (Fe), zinc (Zn), copper (Cu), calcium (Ca), magnesium (Mg), iodine (I) and selenium (Se). Two complementary approaches have been successfully adopted to increase the concentrations of bioavailable mineral elements in food crops. First, agronomic approaches optimizing the application of mineral fertilizers and/or improving the solubilization and mobilization of mineral elements in the soil have been implemented. Secondly, crops have been developed with: increased abilities to acquire mineral elements and accumulate them in edible tissues; increased concentrations of 'promoter' substances, such as ascorbate, β-carotene and cysteine-rich polypeptides which stimulate the absorption of essential mineral elements by the gut; and reduced concentrations of 'antinutrients', such as oxalate, polyphenolics or phytate, which interfere with their absorption. These approaches are addressing mineral malnutrition in humans globally.     

Yeast-Incorporated Gallium Promotes Fracture Healing by Increasing Callus Bony Area and Improving Trabecular Microstructure on Ovariectomized Osteopenic Rats

The purpose of this study was to analyze the impact of yeast-incorporated gallium on fracture healing in ovariectomized osteopenic rats. Forty Wistar female rats used were divided into three groups: sham-operated rats (SHAM), ovariectomized (OVX) rats, and ovx rats treated with yeast-bound gallium (YG). A standardized fracture-healing model with stable plate fixation was established for rat femoral. After 4-week stable fixation, animals were killed to prepare bones for Micro-CT, biomechanical testing, and histomorphometry. In addition, bone samples were obtained to evaluate the content of mineral substances in bones. Quantitative analysis of the bones from animals in the organic gallium group revealed significantly increased mineral contents compared to bones from OVX and SHAM groups. Micro-CT showed that treatment with yeast-incorporated gallium increased BV/TV and trabecular thickness and decreased trabecular separation in ovx animals. Histomorphometric evaluation demonstrated that YG increased callus area and callus bone formation. Yeast-bound gallium also improved the biomechanical properties of bone healing. In conclusion, this study suggests that yeast-incorporated gallium could promote fracture healing in ovariectomized rats.     

Effects of Mineral Supplementation on Liver Cirrhotic/Cancer Male Patients

The aim of the present study was to compare the levels of essential trace and toxic elements in biological samples (blood and serum) of male liver cirrhotic/cancer patients (n?=?144), of age groups 30?C50?years, before and after 60?days treatment with mineral supplementation. For comparison purposes, the same biological samples were also collected from healthy male subjects (n?=?120) of the same age groups. The biological samples were oxidized by 65?% HNO₃/30?% H₂O₂ (2:1) in a microwave oven. The digests of all biological samples were analyzed for arsenic (As), cadmium (Cd), selenium (Se), and zinc (Zn) by electrothermal atomic absorption spectrometry. The levels of Se and Zn were lower in liver cirrhotic/cancer patients as compared to healthy individuals (p?<?0.001). The patients with liver cirrhosis/cancer have twofold higher As and Cd levels in biological samples as compared to age-matched referents. Moreover, a negative correlation was observed between essential and toxic elements. The pathogenesis of liver cirrhosis/cancer has been associated with changes in the balance of certain essential trace and toxic elements. The study confirms that oral supplements of Se and Zn produce metabolic effects in patients with liver cirrhosis/cancer. It was observed that the status of essential trace elements, Se and Zn, was improved in biological samples of all patients after 60?days of treatment with mineral supplementation.     

微量元素对虫草蝠蛾幼虫生长发育的影响

按月采样,分析测定虫草蝠蛾幼虫体微量元素的组成。应用Q模式系统聚类方法,分析了幼虫受环境影响引起的元素代谢变化。结果表明虫体所含元素与环境温度的变化及自身的生理活动密切相关。5、10月份幼虫组的元素含量相近,前者正当幼虫结束休眠后恢复活动的时期,后者是幼虫处于准备进入越冬的前期,两组幼虫此时均处于取食高峰期。3、4月份组的亦较接近,幼虫正渐恢复活动但不取食。8月份幼虫蜕皮前后,消耗较大,需摄取大量食物。计算结果表明7、9月份的元素含量接近,这与上述现象有一定联系;应用对应因子分析法得到的结果是:元素Fe、P对10、11月份幼虫组的贡献值显著;Na、Ca、Mg对8、9月份的贡献值显著;Cu、Zn、Co、Cd、Si对4、5月份的贡献值显著。     

保水剂和丛枝菌根真菌异形根孢囊霉对紫花苜蓿生长与抗旱性的影响

为探讨保水剂（super absorbent polymers,SAP）和丛枝菌根真菌（arbuscular mycorrhizal fungi,AMF）对植物生长和抗旱性的影响,以紫花苜蓿Medicago sativa为供试植物,开展了温室盆栽试验。植物播种时设置土壤添加和不添加聚丙烯酰胺型SAP（BJ2101）处理,以及接种和不接种异形根孢囊霉Rhizophagus irregularis处理,通过称重法维持12%的土壤含水量（正常供水）,植物生长30d,各处理一半植物接受干旱胁迫（6%的土壤含水量）,另一半仍正常供水,持续30d后收获。结果表明,在干旱胁迫下,接种AMF显著增加了紫花苜蓿的植株干重,促进了植物对矿质元素的吸收,提高了叶片中叶绿素和脯氨酸含量,增强了植物的抗旱性。SAP抑制了R. irregularis对植物根系的侵染;与单接种AMF相比,SAP和AMF的联合施用降低了紫花苜蓿的生物量,影响了植物对矿质元素的吸收。本研究中,SAP和AMF的联合施用并没有表现出协同增效作用,这一方面可能是因为研究设定的土壤水分管理模式,另一方面SAP与AMF共同施用的适宜条件还需进一步探索优化。     

The Effects of Exercise and Zinc Deficiency on Some Elements in Rats

The objective of the present study was to determine the effects of exercise and zinc deficiency on some elements in rats. Forty adult male Sprague–Dawley species male rats were allocated to four groups as follows: Group 1: control, Group 2: zinc-deficient, Group 3: exercise in which exercise group fed with a normal diet, Group 4: zinc-deficient exercise, exercise group fed by a zinc-deficient diet for 15 days. After the procedure ended, rats in groups 3 and 4 were exercised on the treadmill for 60 min at a speed of 6 m/min until the exhaustion. The rats were decapitated 48 h after exercise together with their controls, and blood samples were collected to determine copper (Cu), iron (Fe), magnesium (Mg), calcium (Ca), and phosphorus (P) levels. The highest Cu and Fe values in the serum were obtained in group 2 (p < 0.01). The levels of these elements in group 4 were lower than those in group 2 and higher than the levels in groups 1 and 3 (p < 0.01). Serum Mg levels did not differ significantly between groups. Group 4 had the lowest serum Ca and P levels (p < 0.01). These same parameters in Group 2 were higher than those in group 4 but significantly lower than those in groups 1 and 3 (p < 0.01). There was no significant difference between Ca and P levels of groups 1 and 3. The results of the study indicate that zinc deficiency adversely affects copper, iron, calcium, and phosphorus mechanisms and that these adverse effects much more marked after an effort exercise.     

Content of essential and toxic trace elements in organs of obese Wistar and Zucker leprfa rats receiving quercetin

BackgroundThe levels of a number of essential and toxic trace elements in organs and tissues are affected by the disruptions in body homeostasis caused by obesity. Some of these elements may also be influenced by the consumption of biologically active substances of polyphenolic origin, which possess potent abilities to complex with transition metal ions.AimsThe aim of this study was to determine the content of essential and toxic trace elements in Wistar outbred and hereditary obese Zucker Lepr^fa (Z) rats consuming a standard balanced diet or hypercaloric diet with excess fat and fructose, supplemented with quercetin or not supplemented.Materials and methodsMale Wistar and Z rats were fed a control AIN-93M-based semi-synthetic diet or a high-fat-high-carbohydrate diet (HFCD, with 30% fat by weight and 20% fructose provided in the drinking water). A portion of the animals in each line and diet group was administered quercetin at 50 mg/kg body weight. Essential trace elements were included in the diets as a high-purity salt mixture. After the termination of feeding on day 63, the livers, kidneys, and brains of the rats were excised and the content of 16 elements (Fe, Mg, Cu, Mn, Co, Se, Zn, Cr, Ni, Al, Cd, As, Pb, V, Cs, and Ag) was measured by inductively coupled plasma mass spectrometry (ICP-MS).ResultsIn the livers of the Z rats, the contents of Co, Zn, Mg, Fe, Se, and V were reduced and the content of Cr was increased compared to that of the Wistar rats. Supplementation with quercetin significantly decreased liver Fe, V, and Se content, which was more noticeable in the Wistar rats than in the Z rats. In kidneys of Z rats consuming control diet, the contents of Co, Cu, and Cs were decreased whereas those of Ni, Al, and Se were increased compared with the contents in the Wistar rats. The same trend was observed with HFCD feeding except for Cs content. Quercetin reduced kidney V content in both rat lines fed both diets, whereas it reduced Se and Cs only in the Z rats fed control diet. In the brains of the Z rats, a large increase was observed in some trace elements including Pb, Cd, Al, Cr, Ni, Fe, and V compared with the levels in the Wistar rat brains. Supplementation of the control diet with quercetin decreased Al and Ni in the brains of the Z rats.ConclusionThere were significant differences in the mineral content of organs between the Wistar and Z rats, with different propensities for obesity. Moreover some of these effects had no straightforward association with decreased feed consumption or hepatic fat accumulation. When introduced into the diets, quercetin affected the content of essential and toxic elements, but with ambiguous physiological significance. Thus, indicators of essential and toxic trace elements deserve to be used in the protocols of preclinical as well as clinical trials of biologically active substances and food supplements.     

Trace elements in different tissues in aging rats

BackgroundTrace elements (TE) in the human body provide a connecting link between the environment, lifestyle and biochemical modulation of homeodynamics. On the other hand, many non-essential (toxic) elements are linked to numerous diseases. Our study tried to identify differences in TE levels between healthy old and young Wistar rats in blood and the tissues of kidney, liver, heart, and testicles. Furthermore, we wanted to see if there were age-related differences in correlations between essential and/or non-essential (toxic) TE within and between mentioned tissues.MethodsWe used 28 healthy male Wistar rats which were divided into two age groups: young, aged 10 weeks (n = 15) and old, aged 36 months (n = 13). The animals were sacrificed under general anesthesia and the blood samples, and samples from the tissues of the heart, kidneys, testicles, and liver were used for the determination of TE content in them. Analysis of the 16 elements was performed by inductively coupled plasma mass spectrometry (ICP-MS).ResultsToxic elements in old rats (As, Hg, and Cd) were significantly higher in all of the tissues where the difference in levels of these elements was found. Tissues of the kidney and liver had the most correlations between TE in old and young rats, respectively. In both old and young rats, arsenic was the toxic element that had most of the correlations with other essential or non-essential elements. In old rats, most of the TE correlations were detected between the tissues of the kidney and heart (11 correlations), while in young rats most of the correlations were observed between the tissues of kidney and liver, and kidney and testicles (with 9 correlations both).ConclusionsOur study has found significant changes in levels of trace elements in all of the mentioned tissues, with kidney and testicles being the tissues with the most TE differences between the two aged groups. This and other similar studies should encourage other investigators to evaluate the mutual connections between TE and physiological, or the “unhealthy” aging. More studies with more tissues included, more biomarkers of the systemic function, and even molecular methods are needed to provide the answers to numerous questions relating to TE and aging.     

缙云山常绿阔叶林四川大头茶果实中矿质营养元素含量及季节动态

本文测定了缙云山常绿阔叶林中四川大头茶果实中Ｎ,Ｐ,Ｋ,Ｃａ,Ｍｇ,Ｃｕ,Ｚｎ,Ｆｅ,Ｍｎ９种矿质营养元素的含量,研究了这些元素的季节吸收特点与繁殖分配,并探讨了这些元素与某些土壤化学因素之间的关系,结果表明：四川大头茶果实在生长期内矿质营养元素含量随季节而变化,各元素平均含量顺序为：Ｎ＞Ｋ＞Ｃａ＞Ｍｇ＞Ｐ＞Ｍｎ＞Ｆｅ＞Ｚｎ＞Ｃｕ。土壤中化学因子与四川大头茶果实中常量元素含量之间的关系密切,果实中Ｎ含量受土壤中Ｎ,Ｐ,Ｋ含量的综合影响,土壤有机质最终会影响到果实中Ｎ,Ｐ,Ｋ,Ｃａ的吸收,矿质元素的果实繁殖分配量与果实净生物生产量分配之间不存在特定的比例关系。果实元素分配所占比例的大小顺序为Ｐ＞Ｎ＞Ｋ＞Ｃａ＞Ｆｅ＞Ｍｇ＞Ｍｎ＞Ｚｎ＞Ｃｕ。     

Senescence and steroid hormone receptor reactivities in accessory sex glands of elderly rats (Sprague-Dawley) following exogenous hormonal therapy

The aim of this study was to characterize the stromal and epithelial distribution of AR, ERα and ERβ reactivities in the different accessory sex glands of elderly rats and during strong hormonal changes. Ten month old male rats were divided into six senile groups and submitted to treatment: Senile/Control group (SC); Senile/Testosterone group (ST): Senile/Estrogen group (SE); Castrated group (CA); Castrated/Testosterone group (CT); Castrated/Estrogen group (CE). After a 30-day treatment, the prostatic ventral lobe (VL), dorsal lobe (DL) and coagulating gland (CG) samples were processed for immunohistochemistry and Western Blotting. The results showed that AR immunoreactivity was characterized in the epithelium of VL and DL in senile/control rats and senile rats submitted to exogenous hormonal therapy. AR reactivity in the coagulating gland was verified predominantly in the stromal cells in the different experimental groups. ERα reactivity occurred predominantly in the stromal compartment in all accessory sex glands. In the DL and CG, ERα immunoreactivities were intense in the groups which received testosterone (ST) and estrogen (SE). ERβ immunoreactivity in the CG was verified in the stromal compartment in the different experimental groups, showing a positive response to both increased testosterone and estrogen levels. ERβ reactivity, in the DL, was intensified in the stroma of senile rats with higher serum testosterone levels, and in senile rats with increased serum estrogen levels, especially in the glandular epithelium. Thus, the results revealed different distribution pattern of steroid hormone receptors in each one of the prostatic lobes in senescence, especially in the prostate dorsal lobe and coagulating gland, which is a fundamental factor due to the fact that major prostatic diseases occur in a later period of life.     

Polyatomics in zinc isotope ratio analysis of plasma samples by inductively coupled plasma-mass spectrometry and applicability of nonextracted samples for zinc kinetics

Inductively coupled plasma-mass spectrometry (ICP-MS) is a powerful tool for both quantitative multielement analyses of inorganic elements and measurement of isotope ratios (IRs). The main disadvantage of this technique is the existence of polyatomic isobaric interferences at some key masses. Zinc has been investigated for such potential interferences in serum or plasma. The Zn isotopes,⁶⁶Zn and⁶⁸Zn, have no apparent interferences, but³²S¹⁶O₂ and³²S₂ are isobaric with⁶⁴Zn. The possible effects of S and other major components of blood plasma—Na, K, Cl, P, Ca—on Zn IRs were investigated using a series of mineral solutions which simulated human plasma with respect to these elements. The mixture of all mineral elements interfered only with⁶⁴Zn (6.66 ng/mL) and⁷⁰Zn (8.51 ng/mL). Interferences to⁶⁶Zn,⁶⁷Zn, and⁶⁸Zn were minimal containing 0.90, 0.94, and 0.39 ng/mL, respectively. The copresence of Na or S shifted³⁵Cl¹⁶O₂ (atomic mass 67 coming from Cl solution) to³⁵Cl₂ which reduced the contribution to⁶⁷Zn. The hypothesis that Zn IRs obtained from plasma at various intervals after the intravenous administration of enriched⁶⁷Zn to humans would reflect those obtained after extraction of Zn was therefore tested. To compare the two pretreatment methods, “extraction” versus “nonextraction,” specimens were collected from 10 human subjects at intervals of 5 min to 24 h postinjection, and in 4 subjects from 5 min to 9 d postinjection. Two separate aliquots of plasma from each time-point were dried and digested with hydrogen peroxide, and the residue dissolved in nitric acid. One specimen was subjected to zinc extraction using ammonium diethyldithiocarbamate chelate followed by back extraction into nitric acid. The matching aliquot received no further pretreatment. The normalized IRs obtained from⁶⁷Zn/⁶⁶Zn and⁶⁷Zn/⁶⁸Zn in both the “extracted” and “nonextracted” samples agreed well(r ² = 0.976 andr ² = 0.985, respectively) compared to those from other ratios (r ² = 0.838 for⁶⁷Zn/⁶⁴Zn andr ² = 0.747 for⁶⁷Zn/⁷⁰Zn). Considering the minimum possibility of isobaric interferences in plasma samples,⁶⁷Zn/⁶⁸Zn obtained from “nonextracted” samples is sufficient for routine Zn kinetic analysis by ICP-MS.