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Bromides
Published in Stanley R. Resor, Henn Kutt, The Medical Treatment of Epilepsy, 2020
At present it is not known how bromides act to prevent seizures, although there are several theories. As a halide, the bromide ion is handled similarly to chloride. Because its hydrated diameter is less than that of chloride it may pass through the membrane channels more readily and cause a hyperpolarization of the transmembrane potential, making neurons less likely to initiate a seizure discharge or to participate in the spread of the seizure (11). Other studies have shown that benzodiazepine binding is increased in the presence of bromides, suggesting that this ion may affect the function of the benzodiazepine/GABA ionophore (12). Other biochemical measures of GABA neurotransmission are not altered in the presence of bromide (13). It may also inhibit the action of carbonic anhydrase similarly to acetazolamide, which also has some antiepileptic activity (11).
Autoradiography
Published in Howard J. Glenn, Lelio G. Colombetti, Biologic Applications of Radiotracers, 2019
Sven Ullberg, Bengt Larsson, Hans Tjälve
Photographic emulsions are built up of gelatin in which are suspended crystals of silver halide. In the gelatin, the transparent supporting matrix, different chemicals have been dissolved to instill the appropriate physicochemical properties. The grains of silver halide, chiefly bromide, show deficiencies (which actually are carefully controlled chemical contaminations) in the crystal lattices which serve as electron traps, so-called sensitivity specks — the matrices for the formation of latent images. When light or ionizing radiation hits a grain of silver bromide, the energy level of an orbital electron is considered to be increased in such a way that it is set free. A bromide ion is simultaneously oxidized to bromine which is liberated from the surface of the crystal and diffuses into the gelatin. The released electron travels through the crystal until it is captured in a sensitivity speck where it converts a silver ion into a silver atom. This process makes the electron trap still more effective, since the silver atom enlarges it and also exerts an influence on the structure of the whole crystal. When sufficient silver ions have been reduced in this way, a latent image has been formed. Under the influence of the reducing effect of the developer, the silver is reduced altogether in all grains having a latent image.
Chemical Factors
Published in Michael J. Kennish, Ecology of Estuaries Physical and Chemical Aspects, 2019
These two elements occur in seawater mainly as uninegative ions and appear to behave conservatively. Fluoride and bromide are two of the major anions in seawater, existing at a concentration of 68 μmol/kg and 0.84 mmol/kg (at 35.0‰ salinity), respectively. While OH radical reacts with the abundant bromide ion in seawater, this reaction is unimportant in river water because of the scarcity of bromide ion in freshwater.
Oral administration of a potassium bromate dosage: Determination and evaluation of accumulated bromate on the liver of male mice
Published in Drug and Chemical Toxicology, 2022
Mousa Othman Germoush, Ibrahim Hotan Alsohaimi, Ayoub Abdullah Alqadami, Zeid Abdullah Alothman, Hazim Mohammed Ali, Mohammad Saad Algamdi, Abdullah Mohammed Aldawsari
The results revealed that the exposure groups to drinking water containing lower dosages of BrO3− ion concentrations have no detected of accumulated BrO3− in the liver tissues during the study period (1–2 months). It can be seen from Figure 4, the spectrum of group No. 1 (G1) absorptions couldn’t presented any appearance of bromate after exposure to 0.01 mg·L−1 dose for one month and analyzed in 3rd, 4th and 5th weeks (W3, W4, and W5) in comparison with the control sample. Furthermore, the spectrum of group No. 2 (G2) absorptions after exposure to 0.025 mg·L−1 dose for one month and analysis in 3rd, 4th and 5th weeks (W3, W4, and W5) confirming that no accumulated bromate has been detected in the tissues (Figure 4). Also by increasing the dosage up to 0.10 mg·L−1 for one month, the spectrum of group No. 3 (G3) absorptions investigated that no accumulated bromate was detected through the analysis of the G3 in 3rd, 4th and 5th weeks (W3, W4, and W5) Figure 4. These results may have attributed to the reduction of the remaining of bromate to bromide ion in confirming to all these concentrations of BrO3− were safe and could not accumulate in the tissues.
Radiofrequency electric field hyperthermia with gold nanostructures: role of particle shape and surface chemistry
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2018
Seyed Mohammad Amini, Sharmin Kharrazi, Seyed Mahdi Rezayat, Kambiz Gilani
Zeta potential of gold nanostructures in every step of centrifugation and washing was measured (Table 1). Both CTAB-coated (pristine) structures had high and positive zeta potential even after two steps of centrifugation and dispersing in DI water. This is clearly because of the presence of intact CTAB double layer on nanostructures’ surface. But after five steps of washing with centrifugation filter tube, zeta potential decreased significantly. Zeta potential of PEG-coated gold nanostructures was negative while, before dialysis, PEG-coated gold nanostructures exhibited small positive or nearly neutral zeta potential. Because of the importance of PEG coating in in-vivo and in-vitro studies, FTIR and Raman spectroscopy were carried out to further confirm the presence of covalently bound PEG on the surface of nanostructures. To further confirm the presence of PEG molecules on the surface of nanostructures, FTIR spectra of CTAB- and PEG-coated nanostructures were recorded (Figure 5(a,b)). The strong band observed at 1100 nm−1 in the spectra of PEG-coated nanostructures is attributed to stretching of C–O bond which is a clear sign of the presence of PEG molecules on the surface of PEG-coated nanostructures. To finally confirm PEG coating, gold nanostructures made it possible to take advantage of Raman spectroscopy for surface-enhanced Raman scattering. Raman spectra of CTAB-GNRs exhibited a strong band around 170 cm−1 which can be attributed to stretching of Au–Br bond which shifts to 175 cm−1 in PEG-GNRs for stretching of Au–S bond (Figure 5(c)). However, Raman spectrum of PEG-GNRs exhibits another band at 255 cm−1 which can be assigned to bending of Au–S–C bond. Nikoobakht et al. reported an absorption band around 174 cm−1 attributed to Au–Br vibration from bromide ion which is the bridge between the gold nanostructure surface and the positively charged quaternary nitrogen of the CTA+ cation [39]. But based on another report on structural information of the Au–S interface of thiolate-protected gold clusters, strong band at 175 cm−1 was assigned to Au–S–C bending [40]. Additionally, four bands at around 320, 300, 270 and 240 cm−1 were attributed to Au–S vibrations by Dolamic et al. [41]. Therefore, the data are direct indication of PEG coating through Au–S bond.