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1.
Jeffrey W. Adelberg Maria P. Delgado Jeffery T. Tomkins 《In vitro cellular & developmental biology. Plant》2010,46(1):95-107
Residual nutrients from Murashige and Skoog medium were analyzed following a 5-wk multifactor experiment. Plant density, sugar
concentration, and plant growth regulators (benzyladenine and ancymidol) were examined using four genotypes of daylily (Hemerocallis) to determine which factors most influenced nutrient use. Active nutrient uptake was observed for 11 nutrients (potassium,
sodium, copper, phosphorus, iron, calcium, magnesium, manganese, boron, sulfur, and zinc) with lower concentrations in spent
medium than in the tissue water volume (fresh-dry mass expressed as mL H2O). Two patterns of nutrient use were visualized by correlative analysis of nutrient uptake. Greatest growth lowered plant
nutrient concentrations of potassium, sodium, phosphorus, iron, and copper in all genotypes, and luxuriant uptake was indicated
with least growth. Potassium, sodium, iron, and copper concentrations in plant dry matter were equal to or exceeded what is
observed in vigorously growing nursery plants. However, phosphorus concentration in plant dry matter was low enough to be
considered deficient when compared to Hemerocallis plants in nursery production. With a second group of nutrients (calcium, magnesium, manganese, and boron), the genotype,
“Barbara Mitchell” lacked active uptake and was deficient. Calcium concentration was low in all plants compared to Hemerocallis grown under nursery conditions (“Barbara Mitchell” was the lowest concentration) despite active uptake by the other three
genotypes—“Brocaded Gown,” “Mary’s Gold,” and “Heart of a Missionary.” Magnesium concentration in these three genotypes was
low enough in vessels with greatest growth to question its adequacy at high densities. Increased sucrose in medium reduced
the dry matter concentrations of all tested nutrients. Plant growth regulators had less impact on nutrient use than genotype
and plant density. Nutrient uptake may be an important physiological component of genotypic variation. 相似文献
2.
Shun-Zhi Liu Hong Yan Peng Xu Jian-Ping Li Gui-Hua Zhuang Bo-Feng Zhu She-Min Lu 《Biological trace element research》2009,131(3):205-214
The objective of this paper is to investigate the correlation between serum macro-element and trace element contents and bone
mineral density (BMD) as well as the occurrence of osteoporosis. After the epidemiological investigation of 290 postmenopausal
women from ages 45 to 65 in the Xi’an urban area, their blood was collected and serum concentrations of macro-elements, calcium,
phosphonium, potassium, sodium, magnesium, and trace elements, zinc, iron, copper, and selenium were determined using atomic
absorption spectrometry. Their BMD was measured by QDR-2000 dual-energy X-ray absorptiometry (DEXA). The correlation analysis
between BMD and serum element contents was done with the software of SPSS 13.0. The correlation analysis of serum elements
of postmenopausal women showed that there was a significant correlation between serum calcium and the other elements, and
also a significant correlation between serum phosphonium and the others except serum potassium. The serum potassium content
had a significant correlation with serum calcium, sodium and iron, but sodium content showed a significant correlation with
the others except iron and selenium. In addition, copper had a significant correlation with the others except potassium and
selenium. In correlation analysis between BMD and the elements contents, only did the potassium content show a significant
positive correlation with BMD of lumbar vertebra and proximal femora. The comparison results between osteoporosis group, osteopenia
group, and healthy group showed that there was no significant difference in the element contents between the groups, but there
existed a tendency that potassium content increased with the rise of BMD. There exist significant correlations between the
contents of serum elements such as calcium, phosphonium, sodium, potassium, magnesium, zinc, iron, copper, and selenium, but
no significant differences in these elements contents between the osteoporosis group, osteopenia group, and healthy group.
Serum potassium content shows a significant positive correlation with BMD, suggesting potassium may be involved in the development
of osteoporosis in postmenopausal women. 相似文献
3.
Marvin J. Miller Helen Zhu Yanping Xu Chunrui Wu Andrew J. Walz Anne Vergne John M. Roosenberg Garrett Moraski Albert A. Minnick Julia McKee-Dolence Jingdan Hu Kelley Fennell E. Kurt Dolence Li Dong Scott Franzblau Francois Malouin Ute Möllmann 《Biometals》2009,22(1):61-75
Pathogenic microbes rapidly develop resistance to antibiotics. To keep ahead in the “microbial war”, extensive interdisciplinary
research is needed. A primary cause of drug resistance is the overuse of antibiotics that can result in alteration of microbial
permeability, alteration of drug target binding sites, induction of enzymes that destroy antibiotics (ie., beta-lactamase)
and even induction of efflux mechanisms. A combination of chemical syntheses, microbiological and biochemical studies demonstrate
that the known critical dependence of iron assimilation by microbes for growth and virulence can be exploited for the development
of new approaches to antibiotic therapy. Iron recognition and active transport relies on the biosyntheses and use of microbe-selective
iron-chelating compounds called siderophores. Our studies, and those of others, demonstrate that siderophores and analogs
can be used for iron transport-mediated drug delivery (“Trojan Horse” antibiotics) and induction of iron limitation/starvation
(Development of new agents to block iron assimilation). Recent extensions of the use of siderophores for the development of
novel potent and selective anticancer agents are also described. 相似文献
4.
Torben Larsen 《Biological trace element research》1993,39(1):55-71
Soaking of a rat diet, high in both plant phytate and phytase, progressively degraded the phytate content with time of soaking.
This dephytinization in turn enhanced the digestion of feed organic matter in the animals, and it significantly improved the
absorption and retention of minerals and trace elements as observed in balance studies. Incorporation of elements into specific
tissues was evaluated as a reflection of bioavailability. Some tissues did reflect the preceding absorption of certain elements;
other tissues seemed less suitable as indicators of trace element absorption. Dietary calcium addition in many ways contrasted
the soaking procedure: inorganic calcium addition to the feed reduced phosphorus, magnesium, and trace element bioavailability,
and interfered with the internal deposition of the elements.
The external dephytinization of the feed did not affect the phosphohydrolase activity of the intestinal mucosa as manifested
by alkaline phosphatase activity or phytase activity. The mucosal phytase and alkaline phosphatase activities were, however,
mutually correlated, supporting the view that “phytase” activity is a less substratespecific action of alkaline phosphatase
activity or a fraction of this activity. 相似文献
5.
Dumlupinar R Genisel M Erdal S Korkut T Taspinar MS Taskin M 《Biological trace element research》2011,143(3):1740-1745
The present study was performed to determine the changes in inorganic element content in barley leaves of mammalian sex hormones
(MSH). Barley leaves were sprayed with 10−4, 10−6, 10−9, 10−12, 10−15 M concentrations of progesterone, β-estradiol, and androsterone at 7th day after sowing. The plants were harvested at the
end of 18 days after treatment with MSH solutions. The inorganic element concentrations were determined using wavelength dispersive
X-ray fluorescence spectroscopy technique. Although the all MSH concentrations significantly (p < 0.05) increased the concentrations of calcium, magnesium, phosphorus, sulfur, copper, manganese, aluminum, zinc, iron,
potassium, and chlorine, it decreased those of sodium concentration in barley leaves. The maximum changes in the element concentrations
were obtained at 10−9 M for plant leaves treated with progesterone, 10−6 M for plant leaves treated with β-estradiol and androsterone. The present study elucidated that MSH significantly (p < 0.05) affected the inorganic element concentrations in barley leaves. 相似文献
6.
Xuping Liu Liang Zhao Yigang Wang Xu Zhang Wen-Song Tan 《Biotechnology and Bioprocess Engineering》2010,15(3):414-420
One of the major restrictions on the production of adenoviral vectors (AdV) is due to the decrease in virus concentration
concomitant with an increase in cell concentration at infection (CCI) which is known as “cell density effect”, this could
be because of the limited access to the nutrients or significant accumulation of toxic by-products. However, current strategies,
such as developing robust serum-free medium and performing nutrient feeding, will partially address this issue. Therefore,
the objective of this study was to further optimize serum-free culture medium by exploring the influence of calcium ion on
virus production. Our studies showed that an optimal concentration of calcium ion significantly enhances AdV production, especially
at a high CCI. During the virus infection process, a high concentration of calcium ion (≥ 1 mM) caused a reduction in virus
infection efficiency, possibly as a result of cell aggregation. However, by optimizing the timing of the addition of calcium
ion (i.e., 12 hours post-infection [hpi]), high virus infection efficiency could be maintained. The addition of 0.1 to 2 mM calcium
ion at 12 hpi increased virus proliferation dose-dependently. Therefore, the optimal selection of both the concentration and
the supplementation time of calcium ion during the process of AdV production could minimize the “cell density effect,” and
a 2.6- and 3.2-fold increase in virus concentration could be achieved at CCI3 and CCI4, respectively. 相似文献
7.
Copper deficiency lowers brain copper and iron during development. The reduced iron content could be due to hypoferremia.
Experiments were conducted to evaluate plasma iron and “ferroxidase” hypotheses by determining copper and iron status of Holtzman
albino rats following gestational/lactational copper deficiency. Copper deficient (Cu−) dams on treatment for 5 weeks, two
of gestation and three of lactation, had markedly lower copper content of milk and mammary tissue, and lower milk iron. Newborn
pups from Cu− dams had lower copper and iron concentrations. Compared to Cu+ pups, Cu− pups, analyzed between postnatal age
(P) 0 and P26, were smaller, anemic, had lower plasma iron, cardiac hypertrophy, and near zero ceruloplasmin activity. Liver
copper in Cu+ pups increased then decreased during development and major reductions were evident in Cu− pups. Liver iron in
Cu+ pups decreased with age while nursing but increased after eating solid food. Liver iron was lower in Cu− pups at P0 and
P13 and normal at P20 and P26. Small intestinal copper decreased with age in Cu+ pups and was lower in Cu− pups. Intestinal
iron levels in Cu− pups were higher than Cu+ pups postweaning in some experiments. Reduction in plasma iron in Cu− pups is
likely due to a decreased “ferroxidase” function leading to lower placental iron transport, a lower milk iron diet, and partial
block in iron uptake from intestine but is not due to failure to mobilize hepatic iron, in contrast to older rats eating diet
with adequate iron. 相似文献
8.
W. Gregory Hamilton Richard G. Ham 《In vitro cellular & developmental biology. Plant》1977,13(9):537-547
Summary A protein-free synthetic medium, MCDB 301, has been developed for clonal growth of Chinese hamster ovary cell lines. Medium
F12 was developed originally for that purpose, but later failed to support good growth without small amounts of serum protein.
Growth was restored by the addition of nonphysiological amounts of commercially prepared thyroxine or smaller amounts of the
trace element selenium. The thyroxine preparation was shown to contain sufficient selenium to account for all of its growth-promoting
activity. MCDB 301 contains increased concentrations of calcium chloride and glutamine, and a smaller amount of cysteine than
medium F12. It also has been supplemented with 19 inorganic ions, in addition to selenium and those in medium F12, in order
to insure against possible future deficiencies as chemicals are purified further. A Chinese hamster lung line which will not
grow in MCDB 301 alone will grow when the medium is supplemented either with methylcellulose or with insulin. The growth-promoting
activity is thought to be an impurity shared in common by both substances. The probable “essential” role of impurities in
cellular growth in most synthetic media and the problems involved in attempting to develop a truly “defined” medium are discussed.
This research was supported by Grant No. CA15305 from the National Cancer Institute. 相似文献
9.
Sovik Mondal Sudipto Haldar Pinaki Saha Tapan Kumar Ghosh 《Biological trace element research》2010,137(2):190-205
Supplementation of broiler diets with copper, manganese, and zinc at levels higher than that stipulated by the National Research
Council 1994 reportedly improved live weight, feed conversion, and cured leg abnormality supposedly caused by inadequate intake of Mn
and Zn. The objective of the study was to ascertain the effects of plethoric supplementation of copper (Cu), manganese (Mn),
and zinc (Zn) on performance and metabolic responses in broiler chickens. The study also aimed to discriminate the responses
of the birds when the mineral elements were supplemented either in an inorganic or in an organic form. Cobb 400 broiler chickens
(1-day old, n = 300) were assigned to three dietary treatments each containing nine replicates with ten birds for 39 days. The treatments
included a control in which the diet was devoid of supplemental trace elements and treatments supplemented with an inorganic
trace element premix (ITM) and supplemented with a combination of the inorganic and an organic trace element premix (OTM).
The ITM contained (per kilogram) copper, 15 g; iron, 90 g; manganese, 90 g; zinc, 80 g (all as sulfated salts); iodine (as
potassium iodide), 2 g; and selenium (as sodium selenite), 0.3 g. The OTM on the other hand, contained copper, 2.5 g; iron,
15 g; manganese, 15 g; zinc, 13.33 g; and chromium, 0.226 g (all as protein chelates). Plethoric supplementation of trace
elements improved live weight gain and feed/gain ratio (p < 0.05). Leg abnormality developed in the 16% of the control group of birds but not in the supplemented group. Metabolizability
of dry matter, organic matter, and protein was higher (p < 0.01) in the ITM and OTM groups. Excretion of Cu, Fe, and Zn decreased (p < 0.1) due to supplementation of the trace elements leading to increased apparent absorption of the said mineral elements
(p < 0.01). Concentration of the concerned trace elements in serum, liver, and composite muscle samples was higher (p < 0.05) in the ITM and OTM dietary groups indicating an increased deposition of the said mineral elements due to supplementation.
Although the study revealed subtle difference between the inorganic and organic mineral premixes with regards to the parameters
mentioned above, it became apparent that it is possible to reduce excretion of these trace elements by a judicious escalation
in the level of supplementation. The results of the present investigation further revealed that the trace mineral requirement
of broiler chickens suggested by the National Research Council may not be optimum to support the maximum growth potential
of the high yielding strains, and it is reasonable to consider a review of the current NRC recommendations to meet the needs
of the modern birds. 相似文献
10.
P. G. Kostyuk 《Neurophysiology》1997,29(4-5):191-194
Calcium ions are the most universal intracellular messengers transmitting signals from the plasmalemma of excitable cells
to the intracellular structures and triggering or modulating in this way most cellular functions. The molecular mechanisms
responsible for injection of Ca ions into the cytoplasm during cellular activity and for producting transient elevations of
their cytoplasmic free level (calcium “transient,” or “signals”) have been a subject of extensive investigation in numerous
laboratories during last three decades. In a short review it is impossible to summarize the results obtained; two extensive
publications on this subject have appeared already from our laboratory [1, 2]. Therefore, here the main attention will be
paid to the most recent data from our laboratory concerning different aspects of the mechanisms forming calcium signals in
neuronal cells. 相似文献
11.
Leptospirillum ferriphilum has been identified as the dominant, moderately thermophilic, bioleaching microorganism in bioleaching processes. It is an
acidic and chemolithoautrophic bacterium that gains electrons from ferrous iron oxidation for energy production and cell growth.
Genetic information about this microorganism has been limited until now, which has hindered its further exploration. In this
study, the complete genome of L. ferripilum ML-04 is sequenced and annotated. The bacterium has a single circular chromosome of 2,406,157 bp containing 2,471 coding
sequences (CDS), 2 rRNA operons, 48 tRNA genes, a large number of mobile genetic elements and 2 genomic islands. In silico analysis shows L. ferriphilum ML-04 fixes carbon through a reductive citric acid (rTCA) cycle, and obtains nitrogen through ammonium assimilation. The
genes related to “cell envelope biogenesis, outer membrane” (6.9%) and “DNA replication, recombination and repair” (5.6%)
are abundant, and a large number of genes related to heavy metal detoxification, oxidative and acidic stress defense, and
signal transduction pathways were detected. The genomic plasticity, plentiful cell envelope components, inorganic element
metabolic abilities and stress response mechanisms found the base for this organism’s survival in the bioleaching niche. 相似文献
12.
Iron is an essential element for oceanic microbial life but its low bioavailability limits microorganisms in large areas of
the oceans. To acquire this metal many marine bacteria produce organic chelates that bind and transport iron (siderophores).
We have previously shown that algal-associated heterotrophic bacteria belonging to the γ-proteobacterial Marinobacter genus release the siderophore vibrioferrin (VF). The iron-VF complex was shown to be both far more photolabile than all previously
examined photolabile siderophores and to generate a photoproduct incapable of re-chelating the released iron. Thus, the photo-generated
iron was shown to be highly bioavailable both to the producing bacterium and its algal partner. In exchange, we proposed that
algal cells produced dissolved organic matter that helped support bacterial growth and ultimately fueled the biosynthesis
of VF through a light-dependent “carbon for iron mutualism”. While our knowledge of the importance of light to phototrophs
is vast, there are almost no studies that examine the effects of light on microbial heterotrophs. Here, we characterize iron
uptake mechanisms in “algal-associated” VF-producers. Fe uptake by a VF knock-out mutant mimics the wild-type strain and demonstrates
the versatility of iron uptake mechanisms in Marinobacter VF-producers. We also show that VF-producers selectively regulate a subset of their siderophore-dependent iron uptake genes
in response to light exposure. The regulation of iron uptake and transport genes by light is consistent with the light driven
algal–bacterial “carbon for iron mutualism” hypothesis in the marine environment. 相似文献
13.
Trace minerals and atherosclerosis 总被引:1,自引:0,他引:1
W Mertz 《Federation proceedings》1982,41(11):2807-2812
Although there is no evidence for a direct cause-effect relationship between mineral and trace element status and atherosclerosis in humans, many elements exert a strong influence on individual risk factors for cardiovascular disease, such as disorders of blood lipids, blood pressure, coagulation, glucose tolerance, and circulating insulin. Studies in humans and animals have shown that optimal intakes of elements such as sodium, magnesium, calcium, chromium, copper, zinc, and iodine can reduce individual risk factors; some of these studies are consistent with the results of epidemiologic correlations. Influences of local geochemical environment and of dietary practices can result in mineral and trace element imbalances; deficiencies of chromium, iron, copper, zinc, selenium, and iodine are well defined. Detection and correction of such imbalances in populations, through diminishing individual risk factors, might ultimately reduce the incidence of atherosclerotic heart disease. 相似文献
14.
Protein evolution is not a random process. Views which attribute randomness to molecular change, deleterious nature to single-gene
mutations, insufficient geological time, or population size for molecular improvements to occur, or invoke “design creationism”
to account for complexity in molecular structures and biological processes, are unfounded. Scientific evidence suggests that
natural selection tinkers with molecular improvements by retaining adaptive peptide sequence. We used slot-machine probabilities
and ion channels to show biological directionality on molecular change. Because ion channels reside in the lipid bilayer of
cell membranes, their residue location must be in balance with the membrane’s hydrophobic/philic nature; a selective “pore”
for ion passage is located within the hydrophobic region. We contrasted the random generation of DNA sequence for KcsA, a
bacterial two-transmembrane-domain (2TM) potassium channel, from Streptomyces lividans, with an under-selection scenario, the “jackprot,” which predicted much faster evolution than by chance. We wrote a computer
program in JAVA APPLET version 1.0 and designed an online interface, The Jackprot Simulation
, to model a numerical interaction between mutation rate and natural selection during a scenario of polypeptide evolution.
Winning the “jackprot,” or highest-fitness complete-peptide sequence, required cumulative smaller “wins” (rewarded by selection)
at the first, second, and third positions in each of the 161 KcsA codons (“jackdons” that led to “jackacids” that led to the
“jackprot”). The “jackprot” is a didactic tool to demonstrate how mutation rate coupled with natural selection suffices to
explain the evolution of specialized proteins, such as the complex six-transmembrane (6TM) domain potassium, sodium, or calcium
channels. Ancestral DNA sequences coding for 2TM-like proteins underwent nucleotide “edition” and gene duplications to generate
the 6TMs. Ion channels are essential to the physiology of neurons, ganglia, and brains, and were crucial to the evolutionary
advent of consciousness. The Jackprot Simulation illustrates in a computer model that evolution is not and cannot be a random
process as conceived by design creationists. 相似文献
15.
In order to examine the transport of contaminants associated with river-derived suspended particles in the Salton Sea, California,
large volume water samples were collected in transects established along the three major rivers emptying into the Salton Sea
in fall 2001. Rivers in this area carry significant aqueous and particulate contaminant loads derived from irrigation water
associated with the extensive agricultural activity, as well as wastewater from small and large municipalities. A variety
of inorganic constituents, including trace metals, nutrients, and organic carbon were analyzed on suspended material isolated
from water samples collected at upriver, near-shore, and off-shore sites established on the Alamo, New, and Whitewater rivers.
Concentration patterns showed expected trends, with river-borne metals becoming diluted by organic-rich algal particles of
lacustrine origin in off-shore stations. More soluble metals, such as cadmium, copper, and zinc showed a more even distribution
between sites in the rivers and off-shore in the lake basin. General distributional trends of trace elements between particulate
and aqueous forms were discerned by combining metal concentration data for particulates from this study with historical aqueous
metals data. Highly insoluble trace metals, such as iron and aluminum, occurred almost entirely in the particulate phase,
while major cations and approximately 95% of selenium were transported in the soluble phase. Evidence for greater reducing
conditions in the New compared to the Alamo River was provided by the greater proportion of reduced (soluble) manganese in
the New River. Evidence of bioconcentration of selenium and arsenic within the lake by algae was provided by calculating “enrichment”
concentration ratios from metal concentrations on the algal-derived particulate samples and the off-shore sites.
Guest editor: S. H. Hurlbert
The Salton Sea Centennial Symposium. Proceedings of a Symposium Celebrating a Century of Symbiosis Among Agriculture, Wildlife
and People, 1905–2005, held in San Diego, California, USA, March 2005
Roy A. Schroeder—Retired. 相似文献
16.
The regeneration system “Biokol” based on the principles of combining synthetic and natural biopolymers has been investigated.
The wound dressing consists of “large” (200–250 nm) particles of a synthetic biopolymer and a gel component, which consists
of “small” polysaccharide elements 10–20 nm in size. The system can be used both separately and in combination with the gel
complex and cell cultures. In properties (vapor and gas permeability, mechanical properties, conductivity, resistance to microbes,
etc.), it corresponds to the upper layer of the skin. When applied to the wound, the dressing changes its adhesiveness: first,
owing to its hydrophilicity and low hydrophobicity, it closely adheres to the wound surface, and after some time, which corresponds
to the time the polysaccharide complex is released from the dressing, it becomes hydrophobic and easily separates from the
wound. Owing to these properties, the system can be used at all stages of wound healing. 相似文献
17.
A permeant ion is known to create in the channel pore a local electrical field, the intensity of which exceeds the intensity
of an electrical field produced by the membrane potential. In our study, we consider a sodium channel model, in which the
effects of a permeant ion, an inactivating particle, and pharmacological agents on mobile charged groups of the channel are
semi-phenomenologically taken into account by using motion equations for a generalized structural variable. Stationary solutions
for the equation correspond to “open,” “closed,” and “inactivated” channel states. Because of this, the channel free energy
profile, as a function of the structural variable, has three local minima. The three energy values of these states depend
both on the electrical field applied externally and on the near-membrane concentrations of permeant ions and acting pharmacological
agents. Sodium channel activation and inactivation kinetics are considered resulting from relative changes of the free energy
typical of the above three states of the channel. The results we obtained in the course of channel activation and inactivation
modeling and their voltage dependence are qualitatively consistent with the commonly known experimental data. The proposed
model allows one to qualitatively predict the dependence of the sodium channel kinetic characteristics on the concentrations
of permeant ions and pharmacological agents. 相似文献
18.
I. D. Nelson 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1994,164(2):147-155
In all four proboscis muscles of the whelk Buccinum undatum, the potassium-induced depolarization response was acutely dependent upon extracellular calcium, being eliminated in calcium-free
conditions. The responses to acetylcholine were found to be partly dependent upon intracellular calcium. Responses to the
peptides phenylalanine-methionine-arginine-phenylalanine-NH2 and phenylalanine-leucine-arginine-phenylalanine-NH2 were much more resistant to calcium-free conditions and appeared to engage the excitation-contraction coupling mechanism
by mobilizing stored intracellular calcium. Sucrose-gap studies of radular retractor muscles showed that the organic calcium
“antagonist” nifedipine enhanced potassium-induced depolarization responses, initiating spike-like action potentials and associated
fast twitch activity. The inorganic calcium antagonist gadolinium exerted concentration-dependent inhibitory actions on these
muscles. Basal tonus and fast twitch activity in response to potassium-induced depolarization were eliminated as were the
spike-like action potentials of the membrane electrical response. The inorganic calcium “antagonist” cadmium greatly enhanced
potassium-induced contractures in all four muscles, and on its own it induced tonic force and fast twitches in all the muscles.
It seems likely that cadmium may have displaced stored intracellular calcium to induce myofilament activation. While these
molluscan smooth muscles appear to possess calcium channels with fast and slow characteristics, their behaviour and pharmacological
manipulation is very different from their more well known mammalian transient and long-lasting channel counterparts. 相似文献
19.
Suzuki K Higuchi H Iwano H Lakritz J Sera K Koiwa M Taguchi K 《Biological trace element research》2012,145(2):166-171
The aim of this study was to evaluate the reliability and effectiveness of direct determination of trace and major element
concentrations in bronchoalveolar lavage fluid samples from Holstein calves with Mycoplasma bronchopneumonia (n = 21) and healthy controls (n = 20). The samples were obtained during bronchoscopy using a standard examination method. A total of 18 elements (aluminum,
bromine, calcium, chlorine, chromium, copper, iron, potassium, magnesium, manganese, molybdenum, nickel, phosphorous, sulfur,
silicon, strontium, titanium, and zinc) were detected by particle-induced X-ray emission. The average bromine, iron, potassium,
magnesium, and phosphorous concentrations were higher in calves with bronchopneumonia than in controls (p < 0.05). They were found to have higher amounts of calcium and zinc, and a higher zinc–copper ratio than that in healthy
calves (p < 0.001). Based on the receiver operating characteristics curves, we propose a diagnostic cutoff point for zinc–copper ratio
for identification of Mycoplasma pneumonia of 8.676. Our results indicate that assessment of the elemental composition of broncholaveolar lavage fluid is
a promising diagnostic tool for Mycoplasma bronchopneumonia. 相似文献
20.
X-ray radiation is detrimental to human cells and may lead to development of life-threatening diseases. Cigarette paper and
cigarette smoke contain toxic elements, whereas vitamins C and E (VCE) may have regulator effects on the elements. We investigated
effects of VCE administration on X-ray-induced element changes in blood of smoker and nonsmoker X-ray technicians. Twenty
technicians and 30 healthy age-matched control subjects were used in the study. Ten of the X-ray technicians and 15 of the
control were smokers. Blood serum samples were taken from the control. Oral vitamins C (500 mg) and E (150 mg) were supplemented
daily to the smoker and nonsmoker X-ray technicians for 5 weeks. Serum samples were taken from the X-ray technicians before
and after 5 weeks. Copper, zinc, selenium, aluminum, iron, magnesium, and calcium levels were investigated in control and
X-ray technicians, both smokers and nonsmokers. Copper, zinc, and selenium levels were lower in the total X-ray group and
smoker X-ray group than in control and nonsmoker X-ray group, although iron, magnesium, and calcium levels were higher in
X-ray group than in control. The copper, zinc, selenium, and aluminum levels were higher in the VCE treatment group than those
in X-ray group, although magnesium and calcium levels were decreased by the treatment. The serum zinc, copper, selenium, and
magnesium levels were lower in smoker control group when compared to nonsmoker control group. The serum zinc levels were lower
in smoker X-ray group than nonsmoker X-ray group, although iron level was higher in smoker X-ray group than in nonsmoker X-ray
group. VCE prevents the smoke and X-ray-induced selenium, zinc, magnesium, and copper decrease to strengthen the antioxidant
trace element levels in the serum of the technicians. 相似文献