scholarly journals ELEMENTAL ANALYSIS OF PRECIPITATES FORMED IN NUCLEI BY ANTIMONATE-OSMIUM TETROXIDE FIXATION

1972 ◽  
Vol 20 (7) ◽  
pp. 518-526 ◽  
Author(s):  
S. S. SPICER ◽  
A. A. SWANSON

Elements retained in cervical lymph nodes, isolated hepatic nuclei and salt-impregnated gels by fixation with antimonate- or pyrophosphate-containing and other osmium tetroxide solutions were assayed by nuclear activation analysis or by atomic absorption spectrophotometry. Salts preserved by the antimonate-osmium tetroxide fixative in lymph nodes, isolated nuclei and a KCl-enriched gel consisted almost entirely of potassium antimonate. The K+ in the precipitates in these specimens appeared to derive partially from that in the fixative solution and partially from that in the specimen. Salts preserved by the antimonate-osmium tetroxide fixative in an NaCl-supplemented gel consisted partly of potassium antimonate derived from the fixative as in unsupplemented gels and partly of sodium antimonate. The Na+ precipitated in this gel amounted to less than one-half that originally present. In comparison the pyrophosphate-osmium tetroxide solution retained higher levels of K+ in lymph nodes, nuclei and the KCl gel, but the potassium pyrophosphate was not evident as electron-opaque precipitates. The latter fixative was less effective in preserving Na+ in the NaCl gel. The pyrophosphate-containing fixative, which was about twice as efficient as the antimonate-containing solution in retaining the divalent cations, preserved 70% of the Mg++ and 100% of the Ca++ added to gels.

1978 ◽  
Vol 33 (11-12) ◽  
pp. 851-858 ◽  
Author(s):  
Dettmar von Wachtendonk ◽  
Jutta Neef

By use of different inhibitors as well as atomic absorption spectrophotometry it has been shown that the haemolymph-acetylcholinesterase (E. c. 3.1.1.7) of the sea mussel Mytilus edulis is a me- talloprotein containing 2,95 Fe2+ -ions per subunit. All inhibitors used (1,10-phenanthroline, salicylic aldehyde, 2,2′-dipyridyl, 8-hydroxyquinoline) showed a non-competitive inhibition, which was not pH- dependent. Some divalent cations caused a marked increase of the enzyme activity, some heavy metals inhibited the enzyme almost completely; monovalent inorganic cations did not influence the enzyme at all. Besides NaF and Na2SiF6, which showed a non-competitive inhibition comparable to the inhibition observed with the chelating agents, and NaN3 , whose mode of action was not identifiable, no inhibition by different mono- and divalent inorganic anions was to be observed. Ammonium ions caused no enzyme inhibition, but length the inhibition power of substituted ammonium ions increased with an increasing C-chain. The influence of some organic solvents on the enzyme activity is demonstrated.


2014 ◽  
Vol 11 (4) ◽  
pp. 1604-1611
Author(s):  
Baghdad Science Journal

Adsorption studies were carried out to test the ability of the Iraqi rice bran (Amber type) to adsorb some metals divalent cations (Cd2+, Co2+, Cu2+, Fe2+, Ni2+, Pb2+, and Zn2+) as an alternative tool to remove these pollutants from water. The Concentrations of these ions in water were measured using flame and flamless atomic absorption spectrophotometry techniques. The applicability of the adsorption isotherm on Langmuir or Freundlisch equation were tested and found to be dependent on the type of ions. The results showed different adsorptive behavior and different capacities of the adsorption of the ions on the surface of the bran. The correlation between the amounts adsorbed and different cation parameters including (electronegativity, ionic radius, and the second ionization potential) were tested. This study showed the applicability of bran, as a cheap and available waste materials, to remove different cations from solution.


Author(s):  
Soichiro Arai ◽  
Yuh H. Nakanishi

Although many electron microscopic studies on extracted chromatin have provided considerable information on chromatin condensation induced by divalent cations, there is only a little literature available on the effects of divalent cations on chromatin structure in intact nuclei. In the present study, the effects of Mg2+ on chromatin structure in isolated chicken liver nuclei were examined over a wide concentration range of Mg2+ by scanning electron microscopy.Nuclei were prepared from chicken liver by the method of Chauveau et al. with some modifications. The nuclei were suspended in 25 mM triethanolamine chloride buffer (pH7.4) with 1 mM EDTA or in the buffer with concentrations of MgCl2 varying from 1 to 50 mM. After incubation for 1 min at 0°C, glutaraldehyde was added to 1.8% and the nuclei were fixed for 1 h at 4°C. The fixed nuclei were mixed with 15% gelatin solution warmed at about 40°C, and kept at room temperature until the mixture set. The gelatin containing the nuclei was fixed with 2% glutaraldehyde for 2-4 h, and cut into small blocks. The gelatin blocks were conductive-stained with 2% tannic acid and 2% osmium tetroxide, dehydrated in a graded series of ethanol, and freeze-cracked with a razor blade in liquid nitrogen.


JAMA ◽  
1965 ◽  
Vol 194 (1) ◽  
pp. 1-4 ◽  
Author(s):  
A. D. Nicastri

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Rizki Andalia ◽  
Mulia Aria Suzanni ◽  
Rini Rini

Lipstick or lip dye is a cosmetic dose that serves to coloring, decorative the lips, as a moisturizing material and protect the lips from exposure the sun to provide optimum results. Lipstick should not contain chemicals such as lead (Pb) because the Pb is a heavy metal that is very dangerous when continuously used on the skin, because it will be absorbed into the blood and attack the body organ causing the onset of disease. According to BPOM that the lead rate on the lipstick does not exceed the permissible limit of 20 mg/kg or 20 ppm.This research aims to know the levels contained in the samples are 4 brands of matte lipstick that are sold in the Aceh market in Banda Aceh City with the method of atomic absorption spectrophotometry (AAS). The results showed that on the 4 brands of lipstick matte contain heavy metal lead (Pb) with a rate still qualified allowed by BPOM  is samples A, B, C, and D, respectively at 0.24 ppm; 0.10 ppm; 2.87 ppm and 1.32 ppm, so that the 4 brands of lipstick matte are still used.


2013 ◽  
Vol 1 (2) ◽  
pp. 02-06
Author(s):  
SM Anwar Sadat ◽  
Sufia Nasrin Rita ◽  
Shoma Banik ◽  
Md Nazmul Hasan Khandker ◽  
Md Mahfuz Hossain ◽  
...  

A cross sectional study of 29 cases of oral squamous cell carcinoma with or without  cervical lymph node metastasis was done among Bangladeshi patients from January 2006 to December 2007. Majority of the study subjects (34.5%) belonged to the age group of 40-49 years. 58.6% of the study subjects were male, while remaining 41.4% of them were female. 51.7% of the lesions were located in the alveolar ridge where the other common sites were buccal mucosa (27.6%) and retro molar area (13.8%). Half of the study subjects (51.7%) were habituated to betel quid chewing followed by 37.9% and 10.3% were habituated to smoking and betel quid-smoking respectively. Grade I lesions was most prevalent (75.9%) in the study subjects.  Majority of cases presented with Stage IV lesions (55.2%). The sensitivity, specificity, positive predictive value, negative predictive value & accuracy of clinical palpation method for determining metastatic cervical lymph nodes were 93.33%, 64.29%, 73.68%, 90% and 79.3% respectively. Careful and repeated clinical palpation plays important role in evaluation of cervical lymph nodes though several modern techniques may help additionally in the management of oral cancer.DOI: http://dx.doi.org/10.3329/updcj.v1i2.13978 Update Dent. Coll. j. 2011: 1(2): 02-06


2020 ◽  
Vol 6 (1) ◽  
pp. 087
Author(s):  
Rosy Hutami ◽  
M Fakih Kurniawan ◽  
Henna Khoerunnisa

Sumedang tofu is one of favorite foods for Indonesian society. But many sellers or producers are not aware to the food safety of sumedang tofu. The aims of this study were to analyze the microbial, formalin, and lead (Pb) contents in ready-to-eat sumedang tofu which were sold in traffic jams area in Cicurug, Ciawi, and Cisarua. The analysis were carried out by Total Plate Count (TPC) testing for microbial analysis, potassium permanganate reaction (KMnO4) testing for formaldehyde analysis, and atomic absorption spectrophotometry (AAS) method for lead content analysis in the samples. The results obtained for the microbial analysis were sumedang tofu that were sold in the traffic jam areas of Cicurug, Ciawi, and Cisarua contained contaminant above the treshold (1.4 x 105 colonies / gram to 2.2 x 105 colonies / gram of microbes). All of the samples of sumedang tofu were positive containing formaldehyde. Otherwise, there were no lead (Pb) content in all samples regarding to AAS analysis. This study concluded that the ready-to-eat sumedang tofu those were sold in traffic jam area in the Cicurug, Ciawi, and Cisarua were not suitable for consumption because it contained exceed microbial contamination and formalin which are harmful for human health.Keywords : formalin, microbes, sumedang tofu, lead, traffic jam


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