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1.
Increased intake of chromium (Cr) often leads to improvements in glucose, insulin, lipids, and related variables in studies
involving humans and experimental and farm animals. However, the results are often variable, depending not only on the selection
of subjects but also dietary conditions and the form of supplemental Cr used. Our objective was to find a Cr supplement suitable
for humans that was absorbed better than any of those available. Chromium absorption by six adult subjects, three males and
three females, was determined based on the amount of Cr excreted in the urine in the initial 2 d following intake of 200 μg
of Cr of the various forms of chromium tested. The absorption of the newly synthesized complexes was greatest for those containing
histidine. Urinary Cr losses for six control subjects consuming 200 μg of Cr as Cr histidinate increased from basal levels
of 256±48 to 3670±338 ng/d compared with 2082±201 ng for Cr picolinate, the currently most popular nutrient supplement, in
the 48h following Cr consumption. Chromium histidinate complexes were stable and absorption was similar to the initial values
after more than 2 yr. Mixing of some of the complexes with starch, which was postulated to improve Cr absorption, was shown
to essentially block Cr absorption within 1 mo. These data demonstrate that urinary Cr losses need to be determined because
stability and absorption of the Cr complexes varies widely and could be responsible for the variability in some of the Cr
supplementation studies. Chromium ***DIRECT SUPPORT *** A02Q2015 00003 histidinate complexes are absorbed better than any
of the Cr complexes currently available and need to be evaluated as Cr nutritional supplements. 相似文献
2.
Qaisara Pasha Salman A. Malik Nazia Shaheen Munir H. Shah 《Biological trace element research》2010,134(2):160-173
Trace elements including Al, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sr, and Zn were analyzed in the scalp hair
samples of women with malignant breast lesions, women with benign breast lesions, and healthy donors using atomic absorption
spectrophotometric method. In the scalp hair of malignant-tumor patients, the highest average concentration was shown by Ca
(1,187 μg/g), followed by Na (655 μg/g), Mg (478 μg/g), Zn (391 μg/g), Sr (152 μg/g), Fe (114 μg/g), and K (89.8), while in
the case of benign-tumor patients, the average estimated element levels were 1,522, 1,093, 572, 457, 217, 80.4, and 74.7 μg/g,
respectively. Most of the elements exhibited non-normal distribution evidenced by large spread, standard error, and skewness
values. Mean concentrations of Ca (634 μg/g), Zn (206 μg/g), Mg (162 μg/g), Fe (129 μg/g), and Na (82.1 μg/g) were noteworthy
in the scalp hair of healthy women. Average levels of Na, Sr, K, Cd, Co, Pb, Mg, Ca, Zn, Ni, Sb, and Mn were revealed to be
significantly higher in the hair of malignant and benign patients compared to the healthy women; however, Fe, Cu, Al, and
Cr were not significantly different in the scalp hair of the three groups. The quartile distributions of Ca, Cd, Co, Cr, K,
Mg, Mn, Na, Ni, Pb, Sb, and Sr revealed maximum spread in the scalp hair of malignant and benign groups; nevertheless, Al,
Cu, Fe, and Zn exhibited almost comparable quartile levels in the three groups. Strong correlation coefficients were found
between Fe and Cd, Al and Na, Mn and Sr, Co and Cr, Cd and Cr, Pb and K, Pb and Mn, Cu and Na, and Al and Fe in the scalp
hair of malignant-tumor patients, while Fe and K, Cd and Co, Na and Co, and Cr and Pb showed strong correlations in the scalp
hair of benign-tumor patients, both of which were significantly different compared with the healthy subjects. Multivariate
cluster analysis also revealed divergent clustering of the elements in the scalp hair of malignant and benign patients in
comparison with the healthy women. 相似文献
3.
Dominique Bougle François Bureau Joël Voirin Dominique Neuville Michel Drosdowsky Jean-François Duhamel 《Biological trace element research》1992,32(1-3):53-55
Plasma Cr concentrations have been studied in normal children aged 0–14 yr. Levels ranged from 0.65 to 0.88 μg/1 and did not
change with age.
Plasma concentrations of CF patients given 0.5–0.75 μg Cr/kg/d in addition to their diet were similar to normal values. There
was no correlation between these plasma values and growth retardation. 相似文献
4.
José-Angel Cocho José R. Cervilla Maria-Luz Rey-Goldar José-Ramón Fdez-Lorenzo José-Maria Fraga 《Biological trace element research》1992,32(1-3):105-107
Chromium was measured by Electrothermal Atomic Absorption Spectrometry in human milk, cow's milk, and infant formulas. The
mean levels found were 1.56, 0.83, and 4.84 (13%) μg/L, respectively. According to our data, the daily intake for the Spanish
neonates is lower than the Recommended Dietary Allowances (RDAs) (10–40 μg/d) for this element. 相似文献
5.
Eighteen metals were estimated in the scalp hair samples from cancer patients (n = 111) and normal donors (n = 113). Nitric acid–perchloric acid wet digestion procedure was used for the quantification of the selected metals by flame
atomic absorption spectrophotometry. In the scalp hair of cancer patients, highest average levels were found for Ca (861 μg/g),
followed by Na (672 μg/g), Zn (411 μg/g), Mg (348 μg/g), Fe (154 μg/g), Sr (129 μg/g), and K (116 μg/g), whereas in comparison,
the dominant metals in the scalp hair of normal donors were Ca (568 μg/g), Zn (177 μg/g), Mg (154 μg/g), Fe (110 μg/g), and
Na (103 μg/g). The concentrations of Ca, Cd, Co, Cr, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sr, and Zn were notably higher in the
hair of cancer patients as compared with normal donors, which may lead to a number of physiological disorders. Strong positive
correlations were found in Mn–Pb (0.83), Cd–Cr (0.82), Cd–Li (0.57), Fe–Pb (0.56), and Fe–Mn (0.55) in the hair of cancer
patients whereas Na–Cd, Li–Cr, Li–Co, Co–Cd, Li–Cd, Na–Co, Na–Li, Ca–Mg and Na–Cr exhibited strong relationships (r > 0.50) in the hair of normal donors. Principal Component Analysis (PCA) of the data revealed seven PCs, both for cancer
patients and normal donors, but with significantly different loadings. Cluster Analysis (CA) was also used to support the
PCA results. The study evidenced significantly different pattern of metal distribution in the hair of cancer patients in comparison
with normal donors. The role of trace metals in carcinogenesis was also discussed. 相似文献
6.
Phorbol myristate acetate (PMA) causes acute lung injury (ALI). The present study was designed to elucidate the role of nitric
oxide (NO), inducible NO synthase (iNOS), neutrophil elastase (NE) and other mediators in the ALI caused by PMA. In isolated
rat’s lungs, PMA at various doses (1, 2 and 4 μg/g lung weight) was added into the lung perfusate. Vehicle group received
dimethyl sulfoxide (the solvent for PMA) 100 μg/g. We measured the lung weight changes, pulmonary arterial pressure, capillary
filtration coefficient, exhaled NO, protein concentration in bronchoalveolar lavage (PCBAL) and Evan blue dye leakage. Nitrate/nitrite,
methyl guanidine, proinflammatory cytokines, NE and myeloperoxidase (MPO) in lung perfusate were determined. Histopathological
examination was performed. We detected the iNOS mRNA expression in lung tissue. PMA caused dose-dependent increases in variables
for lung changes, and nitrate/nitrite, methyl guanidine, proinflammatory cytokines, NE and MPO in lung perfusate. The pathology
was characterized by alveolar hemorrhagic edema with inflammatory cell infiltration. Scanning electron microscopy revealed
endothelial damage. PMA upregulated the expression of iNOS mRNA. Our results suggest that neutrophil activation by PMA causes
release of NE, upregulation of iNOS and a series of inflammatory responses leading to endothelial damage and ALI. 相似文献
7.
Król E Krejpcio Z Byks H Bogdański P Pupek-Musialik D 《Biological trace element research》2011,143(2):726-737
Chromium(III) is considered as an essential element for carbohydrate and lipid metabolism. The aim of this clinical study
was to evaluate the efficacy of Cr brewer’s yeast supplementation on body mass, carbohydrate, lipids and mineral indices in
type 2 diabetic patients. Twenty adult type 2 diabetic subjects (11 males and 9 females aged 37–63) were supplemented with
Cr brewer’s yeast in dosages of 500 μg Cr/person/day or placebo for 8 weeks in a double-blind, placebo-controlled crossover
design. It was found that supplemental Cr did not affect body mass, blood lipid profile, resistin levels, and the serum and
hair Zn, Fe, and Cu levels, but increased serum Cr (by 116%) and hair Cr (by 20.6%) concentrations and improved some blood
carbohydrate indices (significant increase in the β cell function index by 18.8%) in type 2 diabetic patients. In conclusion,
Cr brewer’s yeast has a weak hypoglycemic potential, but does not affect body mass, blood biochemical profile, and microelement
levels in type 2 diabetic subjects. 相似文献
8.
Scanning (SEM) and transmission electron microscopy (TEM) were used to examine the effect of dietary copper deficiency and
hyperbaric hyperoxia, alone and in combination, on lung structure. Male, weanling Sprague-Dawley† rats were fed a copper-deficient (CuD, 0.2 μg/g) or copper-adequate diet (CuA, 5.1 μg/g). After 35–41 d on their respective
diets, rats from each group were placed inside a pressure vessel kept at 27°C under one of two pressure protcols. Air controls
were maintained at 1 atm for 75 min. Rats exposed to oxygen were maintained at 1 atm of air plus 3 atm of oxygen for 1 h and
then decompressed for 15 min. Under SEM, none of the treated lungs (CuD, CuA-O2 exposed, or CuD-O2 exposed) showed abnormal lung morphology from the conducting bronchioles down to the alveoli. Copper-deficient red blood
cells were abnormally shaped. Under TEM, CuA-O2-exposed lungs showed thicker respiratory membranes, especially basement membranes and endothelial cells, and alveolar Type
II cells having more than the usual number of surfactant vacuoles. CuD lungs also showed thicker endothelial and basement
membrane components of the respiratory membrane, but normal looking Type II cells. CuD-O2-exposed lungs showed greatly thickened respiratory membranes and severe disruption of both endothelium and basement membrane
and, judging by the increased number of nuclei per field, an increase in the number of both Type I and Type II cells. We conclude
that copper deficiency enhances the damage caused by O2 toxicity, an effect that may be caused by reduced antioxidant status. 相似文献
9.
Mesorhizobium strain RC3, isolated from chickpea nodules, tolerated chromium up to 500 μg/ml and reduced it by 90% at pH 7 after 120 h.
It produced plant growth-promoting substances, both in the presence and absence of chromium. Strain RC3 produced 35 μg indole
acetic acid/ml in Luria Bertani broth with 100 mg tryptophan/ml, which decreased with an increase in chromium concentration.
Chromium application to soil at 136 mg/kg was toxic to chickpea plants but when RC3 at 136 mg/kg was also added, it increased
the dry matter accumulation, number of nodules, seed yield and grain protein by 71, 86, 36 and 16%, respectively, compared
to non-inoculated plants. Nitrogen in roots and shoots were increased by 46 and 40%, respectively, at 136 mg Cr/kg. The bio-inoculant
decreased the uptake of chromium by 14, 34 and 29% in roots, shoots and grains, respectively. 相似文献
10.
Chromium accumulation and toxicity in aquatic vascular plants 总被引:2,自引:0,他引:2
Chromium poisoning among leather tanners has long been known. The workers have been found to suffer from ulcers, allergic
dermatitis, lung cancer, and liver necrosis due to prolonged contact with chromium salts. One of the highly catastrophic incidences
of lung cancer as a result of inhaling dust containing Cr (VI) was reported in 1960 from the Kiryama factory of the Nippon-Denko
concern on the island of Hokkaido, Japan.
Pollution of water resources, both surface and underground, by indiscriminate discharge of spent wastes of chromium-based
industries has become a serious global concern, for it has created an acute scarcity of safe drinking water in many countries.
In August 1975 it was observed that underground drinking water in Tokyo near the chromium (VI))-containing spoil heaps contained
more than 2000 times the permissible limit of chromium. In Ludhiana and Chennai, India, chromium levels in underground water
have been recorded at more than 12 mg/L and 550–1500 ppm/L, respectively.
Chromium is widely distributed in nature, occupying 21st position in the index of most commonly occurring elements in the
earth’s crust. Chromium occurs in nature in the form of a compound (chromium + oxygen + iron) known as “chromite.” The geographical
distribution of chromite mines is uneven. Over 95% of economically viable chromite ores are situated in the southern part
of Africa. Its annual global production is ca. 9 million tons, mainly mined in the former Soviet Union, Albania, and Africa.
In India, over 90% of chromite deposits are located in Sukinda Valley of Orissa.
Chromium occurs in several oxidation states, ranging from Cr2+ to Cr6+, with trivalent and hexavalent states being the most stable and common in the terrestrial environment. Chromium (III) is
used for leather tanning because it forms stable complexes with amino groups in organic material. In the presence of excessive
oxygen, chromium (III) oxidizes into Cr (VI), which is highly toxic and more soluble in water than are other forms. Chromium
(VI) can easily cross the cell membrane, whereas the phosphate-sulphate carrier also transports the chromite anions. On the
other hand, Cr (III) does not utilize any specific membrane carrier and hence enters into the cell through simple diffusion.
The diffusion is possible only after the formation of appropriate lipophilic ligands.
Use of chromium as industrial material was discovered only 100 years ago. It was used for the first time in the production
of corrosion-resistant steel (stainless steel) and coatings. Subsequently, chromium was widely deployed in various industries;
namely, electroplating, dyes and pigments, textiles, photography, and wood processing. The tanning industry is one of the
major users of chromium (III) salts. During leather processing the conversion of putrefactive proteinaceous matter, skin,
into non-putricible is carried out by the treatment of chromium sulphate solution. According to an estimate, ca. 32 tons of
chromium sulphate salts are used annually in Indian tanneries. As a result of unplanned disposal of spent tannery wastes,
ca. 2000–3200 tons of chromium as element escapes into the environment. This has raised severe ecological concern and reduced
the forest cover considerably.
Aquatic vascular plants play an important role in the uptake, storage, and recycling of metals. The uptake of metals depends
on the chemical form present in the system and on the life form of the macrophytes (floating, free floating, well rooted,
or rootless). The free-floating species (Eichhornia, Lemna, Pistia) absorb elements through the roots/leaves, whereas the rootless speciesCeratophyllum demersum absorbs mainly through the finally divided leaves.
Submerged species showed higher chromium accumulation than do floating and emergent ones. The order is:Elodea canadensis > Lagarosiphon major > Potamogeton crispes > Trapa natans > Phragmitis communis. Roots of water hyacinth (Eichhornia crassipes) showed an accumulation of 18.92 μmol (g dry tissue wt-1) Cr. AlthoughCeratophyllum demersum andHydrodictyon reticulatum showed lower levels of chromium accumulation, their bioconcentration factor values were very high.
Floating-species duckweeds (Lemna, Spirodela) are potential accumulators of heavy metals. They have bioconcentrated Fe and Cu, as high as 78 times their concentration
in wastewater. Duckweeds have also shown the ability to accumulate chromium substantially. Although duckweeds attain higher
concentrations of chromium in their tissues than do other macrophytes, their bioconcentration factor (BCF) values were much
lower than those reported in other aquatic species.
A moderate accumulation of chromium has been found in emergent species. Plants ofScirpus validatus andCyperus esculentus accumulated 0.55 kg and 0.73 kg-1 Cr, respectively. InBacopa monnieri andScirpus lacustris accumulations of 1600 and 739 μg g-1 dw Cr, respectively, have been reported when exposed to 5 mg L-1 Cr for 168 hours in solution culture. The accumulation of Cr was greater in the root than the shoot. Higher accumulations
of chromium in roots and least in shoots of emergent species have also been recorded.
Phytotoxicity of chromium in aquatic environment has not been studied in detail. The mechanism of injury in terms of ultrastructural
organization, biochemical changes, and metabolic regulations has not been elucidated. It has been pointed out that while considering
the toxicity of heavy metals, a distinction should be made between elements essential to plants and metals that have no proven
beneficial biochemical effects. For example, an increased level of chromium may actually stimulate growth without being essential
for any metabolic process. In aquatic species—namely,Myriophyllum spicatum— the maximum increase in shoot length was found at 50 μgl-1 Cr. Higher concentrations up to 1000 μ gl-1 caused an almost linear reduction both in shoot weight and length. Duckweeds showed relatively greater tolerance to chromium.
However, an inhibition of growth inSpirodela andLemna was found at 0.02 mM and 0.00002 mM Cr concentrations, respectively. Mortality ofL. aequinoctialis was found at 0.005 mM Cr and higher concentrations. The effective chromium concentrations (EC-50) for some aquatic species
have been reported as follows:Lemna minor, 5.0 mg L-1, 14 days EC;L. Paucicostata, 1.0 mg L-1, 20 days EC;Myriophyllum spicatum, 1.9 mg L-1, 32 days EC; andSpirodela polyrrhiza, 50 mg L-1, 14 days EC.
Chromium toxicity on biochemical parameters showed a reduction in photosynthetic rate at 50 μgl-1 Cr inMyriophyllum spicatum. Decrease in chlorophyll and protein contents were also recorded inNajas indica, Vallisneria spiralis, andAlternanthera sessilis with an increase in chromium concentration. InLimnanthemum cristatum, a slight reduction in chlorophyll and almost no change in control were found due to chromium toxicity. Submerged species
(Ceratophyllum demersum, Vallisneria spiralis) and an emergent one (Alternanthera sessilis) showed decreases in chlorophyll as well as in protein contents when treated with chromium.
Chromium-induced morphological and ultrastructural changes have been reported in several aquatic vascular plants: InLemna minor andCeratophyllum demersum, chromium-induced changes in chloroplast fine structure disorganized thylakoids with loss of grain and caused formation of
many vesicles in the chloroplast. Chromium (VI) has caused stunting and browning of roots produced from the chromium-treated
excised leaves ofLimnanthemum cristatum. At 226 μg/g Cr dry wt leaf tissue concentration, development of brown coloration in the hydathodes of juvenile leaves ofLimnanthemum cristatum is a characteristic chromiuminduced alteration.
Aquatic vascular plants and algae may serve as effective bioindicators in respect to metals in aquatic environments. Chromium-induced
morphological and ultrastructural changes inLimnanthemum cristatum have significant indicator values and could be used for assessing the level of chromium in ambient water.Wolffia globosa, a rootless duckweed, showed substantial chromium accumulation and high concentration factor (BCF) value at very low ambient
chromium concentrations, suggesting its feasibility in detecting chromium pollution in water resources. Methylene blue-stained
cells ofScenedesmus acutus become uniformly dark blue during chromium (VI) treatment. This may serve as an indicator of chromium pollution. 相似文献
11.
Miaomiao Zhang Mengjia Qian Yonghua Zheng Meiyi Li Sanda M. Cretoiu Chengshui Chen Luonan Chen Dragos Cretoiu Laurentiu M. Popescu Hao Fang Xiangdong Wang 《Journal of cellular and molecular medicine》2014,18(10):2044-2060
Telocytes (TCs) were identified as a distinct cellular type of the interstitial tissue and defined as cells with extremely long telopodes (Tps). Our previous data demonstrated patterns of mouse TC‐specific gene profiles on chromosome 1. The present study focuses on the identification of characters and patterns of TC‐specific or TC‐dominated gene expression profiles in chromosome 2 and 3, the network of principle genes and potential functional association. We compared gene expression profiles of pulmonary TCs, mesenchymal stem cells, fibroblasts, alveolar type II cells, airway basal cells, proximal airway cells, CD8+T cells from bronchial lymph nodes (T‐BL), and CD8+ T cells from lungs (T‐LL). We identified that 26 or 80 genes of TCs in chromosome 2 and 13 or 59 genes of TCs up‐ or down‐regulated in chromosome 3, as compared with other cells respectively. Obvious overexpression of Myl9 in chromosome 2 of TCs different from other cells, indicates that biological functions of TCs are mainly associated with tissue/organ injury and ageing, while down‐expression of Pltp implies that TCs may be associated with inhibition or reduction of inflammation in the lung. Dominant overexpression of Sh3glb1, Tm4sf1 or Csf1 in chromosome 3 of TCs is mainly associated with tumour promotion in lung cancer, while most down‐expression of Pde5 may be involved in the development of pulmonary fibrosis and other acute and chronic interstitial lung disease. 相似文献
12.
N A Beliakov V B Serikov D N Cherniakova 《Arkhiv anatomii, gistologii i émbriologii》1984,86(6):42-48
In order to study the role of the bronchial vascular system in pulmonary protein transport, experiments have been performed in 6 anesthesized dogs, 16 isolated canine lungs and 10 white rats. When bilateral ligation of the bronchial arteries is performed in the anesthesized dogs, cessation of the bronchial blood stream results in decreasing protein transport and lymph outflow from the lungs. In the isolated canine lungs perfused through the pulmonary and bronchial vessels, lymph formation is determined by presence of the bronchial perfusion. As demonstrated the electron microscopical investigations with the marker of the protein transport--horseradish peroxidase--for 15 min of observation the marker does not get out of the limits of endothelium in the pulmonary capillaries. During this time horseradish peroxidase gets out of the bronchial vessels into the loose connective tissue of the lung, the lymphatic capillaries and the alveolar epithelium. Therefore, it is possible to make a conclusion on a predominated role of the protein transport in the lungs out of the bronchial vascular system as compared to the pulmonary system. 相似文献
13.
Peptidergic innervation of rat lymphoid tissue and lung: Relation to mast cells and sensitivity to capsaicin and immunization 总被引:5,自引:0,他引:5
G. Nilsson K. Alving S. Ahlstedt T. Hökfelt J. M. Lundberg 《Cell and tissue research》1990,262(1):125-133
Summary The peptidergic innervation of lymphoid tissue and the lung in relation to mast cells was studied in rat. The sensitivity of neuropeptide-containing nerves to capsaicin treatment and immunization was also examined. Measurements of the content of neurokinin A and calcitonin gene-related peptide revealed that the lung contained the highest content of both neuropeptides; lymph nodes had intermediate levels, whereas the spleen had the lowest content. Immuhohistochemistry showed that the calcitonin gene-related peptide- and neurokinin A-immunoreactive nerves in lymph nodes were mainly found around blood vessels, whereas in the lung the nerves were present within the lining respiratory epithelium, bronchial smooth muscle, around blood vessels and close to lymphoid aggregates. Combined immunohistochemistry for serotonin (5-hydroxytryptamine), as a marker for mast cells, and tachykinins or calcitonin gene-related peptide revealed that a close association was often present between the nerves and 5-hydroxytryptamine-positive cells in the bronchi of the lung, while 5-hydroxytryptamine-positive cells were not observed in lymph nodes. The neurokinin A and calcitonin gene-related peptide content in lymph nodes, spleen and lung, but not the content of neuropeptide Y, was markedly decreased by capsaicin treatment, suggesting a sensory origin for the two former peptides. Aerosol immunization increased the levels of calcitonin gene-related peptide in the lung, whereas the content in mediastinal lymph nodes was not affected. These data demonstrate a peptidergic innervation mainly of blood vessels in lymphoid tissue and a close relation between sensory nerves and mast cells as well as lymphoid aggregates in the bronchi of the lung. This further suggests that the sensory innervation of lymph nodes is mainly related to regulation of vascular tone and lymph flow. Furthermore, at the site of immunization, i.e., in the airway mucosa, sensory nerve mediators may interact both with mast cells and lymphoid cells. 相似文献
14.
C57B1/6 female mice were infected with an intrapulmonary dose of 2.5 × 104 BCG(Mycobacterium bovis Bacillus Calmette-Guerin). Lymphocyte populations in lung interstitium and lung-associated tracheal lymph nodes (LN) were
examined at 1,2, 4, 5, 6, 8 and 12 weeks after infection. BCG load in lungs peaked between 4–6 weeks post-infection and declined to very
low levels by the 12th week of infection. Lung leukocytes were obtained over the course of infection by enzyme digestion of
lung tissue followed by centrifugation over Percoll discontinuous density gradients. By 4 to 6 weeks after infection, numbers
of lung leukocytes had more than doubled but the proportions of lymphocytes (about 70%), macrophages (about 18%) and granulocytes
(about 12%) remained essentially unaltered. Flow cytometric studies indicated: (i) the total number of CD3+ T cells in lungs increased by 3-fold relative to uninfected controls at 5 to 6 weeks post-infection, but the relative proportions
of CD4 and CD8 cells within the T cell compartment remained unaltered; (ii) relative proportion of NK cells in lungs declined
by 30% but the total number of NK cells (NK1.1+) per lung increased by about 50%, 5–6 weeks post infection; (iii) tracheal LN underwent marked increase in size and cell
recoveries (6-10-fold increase) beginning 4 weeks after infection. While both T and B cells contributed to the increase in
cell recoveries from infected tracheal LNs, the T/B ratio declined significantly but CD4/CD8 ratio remained unaltered. In
control mice, IFNγ producing non-T cells outnumbered T cells producing IFNγ. However, as the adaptive response to infection
evolves, marked increase occur in the number of IFNγ producing T cells, but not NK cells in the lungs. Thus, T cells are the
primary cell type responsible for the adaptive IFNγ response to pulmonary BCG infection. Few T cells in tracheal LN of BCG
infected mice produce IFNγ, suggesting that maturational changes associated with migration to the lungs or residence in the
lungs enhance the capability of some T cells to produce this cytokine 相似文献
15.
R. Lee D. J. Cousins E. Ortiz‐Zapater R. Breen E. McLean G. Santis 《Cytopathology》2013,24(6):351-355
R. Lee, D. J. Cousins, E. Ortiz‐Zapater, R. Breen, E. McLean and G. Santis Gene expression profiling of endobronchial ultrasound (EBUS)‐derived cytological fine needle aspirates from hilar and mediastinal lymph nodes in non‐small cell lung cancer Objective: Endobronchial ultrasound (EBUS) allows minimally invasive sampling of hilar and mediastinal lymph nodes and has an established role in non‐small cell lung cancer (NSCLC) diagnosis and staging. Molecular biomarkers are being explored increasingly in lung cancer research. Gene expression profiling (GEP) is a microarray‐based technology that comprehensively assesses genome‐wide changes in gene expression that can provide tumour‐specific molecular signatures with the potential to predict prognosis and treatment responsiveness. We assessed the feasibility of using EBUS‐derived aspirates from benign and tumour‐infiltrated lymph nodes for GEP. Methods: RNA was extracted from EBUS‐directed transbronchial fine needle aspiration samples in routine clinical practice. GEP was subsequently performed in six patients with NSCLC, three of whom had tumour‐infiltrated nodes and three who had benign lymph nodes; the differences in gene expression were then compared. Results: RNA was successfully extracted in 29 of 32 patients, 12 of whom were diagnosed with NSCLC. RNA yield (median, 12.1 μg) and RNA integrity (median, 6.3) were sufficient after amplification for GEP. Benign and malignant nodes in adenocarcinoma were discriminated by principal component analysis and hierarchical clustering with different expression patterns between malignant and benign nodes. Conclusion: We have demonstrated the feasibility of RNA extraction and GEP on EBUS‐derived transbronchial fine needle aspirates from benign and tumour‐infiltrated lymph nodes in patients with known NSCLC in routine clinical practice. Further studies on larger patient cohorts are required to identify expression profiles that robustly differentiate benign from malignant lymph nodes in NSCLC. 相似文献
16.
Richard A. Anderson Noella A. Bryden Marilyn M. Polansky 《Biological trace element research》1992,32(1-3):117-121
Chromium content of 22 daily diets, designed by nutritionists to be well-balanced, ranged from 8.4 to 23.7 μg/1000 cal with
a mean ±SEM chromium content of 13.4±1.1 μg/1000 cal. Most dairy products are low in chromium and provide <0.6μg/serving.
Meats, poultry, and fish are also low in chromium, providing 2 μg of chromium or less per serving. Chromium contents of grain
products, fruits, and vegetables vary widely, with some foods providing >20 μg/serving. In summary, chromium content of individual
foods varies, and is dependent upon chromium introduced in the growing, transport, processing, and fortification of the food.
Even well-balanced diets may contain suboptimal levels of dietary chromium. 相似文献
17.
This study is a part of a monitoring program for the determination of metals in various human tissues of the population living
in the vicinity of a new hazardous waste incinerator (HWI) in Constantí (Tarragona County, Spain). Concentrations of arsenic
(As), beryllium (Be), cadmium (Cd), chromium (Cr), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), tin (Sn), thallium
(Tl), and vanadium (V) were determined in brain, bone, kidney, liver, and lung autopsy samples collected in 2003 from 22 individuals
who had been living for at least 10 yr in the area under evaluation. Results were compared with the metal levels obtained
in a baseline study, which was performed during the construction of the HWI (1996–1998). In the present survey, As, Be, Tl,
and V levels were not detected in any of the analyzed tissues, while Cr concentrations were very close to the limit of detection.
The highest levels of Cd and Hg were found in kidney (17.46 μg/g and 0.23 μg/g, respectively), those of Mn in liver (1.07
μg/g), and those of Ni, Pb, and Sn in bone (1.16 μg/g, 2.11 μg/g, and 0.34 μg/g, respectively). In comparison to the results
of the baseline study, a general reduction of most metal concentrations was observed in the current survey. 相似文献
18.
The effect of different concentrations of Na2SeO3 on human pulmonary adenocarcinoma cells and human embryonic lung diploid cells in vitro was investigated. For human pulmonary
adenocarcinoma cells, mitotic index and cell count decreased with increasing selenium concentrations. At 1 μg/mL sodium selenite,
mitotic activity and growth of human lung cancer cells were partially inhibited, and the progression of human lung cancer
cell cycle was partially arrested. When human embryonic lung diploid cells were treated with 1 μg/mL sodium selenite for five
continuous days, cell counts of the treated group were closely parallel to those of the control group. After treating human
embryonic lung diploid cells with 1–5μg/mL sodium selenite for 1–3 d, the mitotic index (MI), labeled index (LI), and average
silver grain (SG) number per 20 labeled nuclei were the same as those of the control. In mixed cultures of human embryonic
lung diploid cells and human pulmonary adenocarcinoma cells, treated with 3 and 5 μg/mL sodium selenite for 24 h, the lung
diploid cells showed a normal fusiform morphology, whereas the lung cancer cells showed heavily vacuolated cytoplasms and
distorted nuclei. 相似文献
19.
Caulogenic responses of various explant types from 12-month-old plants of Hemidesmus indicus were tested. Second and third visible nodes (0.5 cm) from the apex and root segments (0.5 cm) were the most and least regenerative
respectively, with the formation of 9.37 and 2.6 shoots in 4 weeks on half strength MS medium supplemented with 2.22 μM BA
and 1.07 μM NAA and 4.44 μM BA and 2.69 μM NAA respectively. Caulogenic ability of the nodes decreased with increasing maturity.
Shoot buds initiated upon the young nodes on day 10 developed into 7.2 cm long shoots within 4 weeks thereby making a shoot
elongation phase unnecessary. Nodal explants of the in vitro raised shoots subcultured in the same medium produced 9.32 shoots of 7.1 cm length in 3–4 weeks, similar to those of the
mature plant-derived nodes. Multiplication through subculture of the nodes up to 25 passages of 4 weeks each was achieved
without decline. Shoot cultures were rooted in quarter salt strength MS medium containing 9.8 μM IBA and the rooted plants
were hardened for establishment in pots at 96% rate. Four months after establishment, the micropropagated plants were stable
and showed uniform morphological and growth characteristic. After 12 months of cultivation in the field, on an average micropropagated
plant consisted of 4–5 shoots, 5–8 branches per shoot and increased root biomass (13.5 g) compared to the poor growth (single
shoot and 2–3 branches) and root production (4.6 g) values obtained with plants raised from conventional rooted stem cuttings.
The concentration of the root specific compound, 2-hydroxy 4-methoxy benzaldehyde per plant was 2–3 fold higher in micropropagated
plants though on unit dry root biomass (0.12% per g dry wt) basis it remained the same between two sources of plants.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
20.
Ayhan Dogukan Nurhan Sahin Mehmet Tuzcu Vijaya Juturu Cemal Orhan Muhittin Onderci James Komorowski Kazim Sahin 《Biological trace element research》2009,131(2):124-132
The present study was conducted to investigate the effects of chromium histidinate (CrHis) against experimentally induced
type II diabetes and on chromium (Cr), zinc (Zn), selenium (Se), manganese (Mn), iron (Fe), and copper (Cu) in serum, liver,
and kidney of diabetic rats. The male Wistar rats (n = 60, 8 weeks old) were divided into four groups. Group I received a standard diet (12% of calories as fat); group II were
fed standard diet and received CrHis (110 mcg CrHis/kg body weight per day); group III received a high-fat diet (HFD; 40% of calories as fat) for 2 weeks and then
were injected with streptozotocin (STZ) on day 14 (STZ, 40 mg/kg i.p.; HFD/STZ); group IV were treated as group III (HFD/STZ)
but supplemented with 110 mcg CrHis/kg body weight per day. The mineral concentrations in the serum and tissue were determined
by atomic absorption spectrometry. Compared to the HFD/STZ group, CrHis significantly increased body weight and reduced blood
glucose in diabetic rats (p < 0.001). Concentrations of Cr, Zn, Se, and Mn in serum, liver, and kidney of the diabetic rats were significantly lower
than in the control rats (p < 0.0001). In contrast, higher Fe and Cu levels were found in serum and tissues from diabetic versus the non-diabetic rats
(p < 0.001). Chromium histidinate supplementation increased serum, liver, and kidney concentrations of Cr and Zn both in diabetic
and non-diabetic rats (p < 0.001). Chromium supplementation increased Mn and Se levels in diabetic rats (p < 0.001); however, it decreased Cu levels in STZ-treated group (p < 0.001). Chromium histidinate supplementation did not affect Fe levels in both groups (p > 0.05). The results of the present study conclude that supplementing Cr to the diet of diabetic rats influences serum and
tissue Cr, Zn, Se, Mn, and Cu concentrations. 相似文献