A suicidal heavy metal poisoning mimicking corrosive acid poisoning: A rare case report

Ingestion of corrosive substances may cause severe to serious injuries of the upper aero-digestive tractand the poisoning can even result in death. Acute corrosive intoxications pose a major problem in clinical toxicology since the most commonly affected population are the young with psychic disorders, suicidal intent and alcohol addiction. In our case report, a 19-year-old male, 2year engineering student committed suicide by consuming a heavy metal salt available in his chemistry lab after leaving a suicidal note. He got treated in a private hospital for 2 days and later he succumbed due to poisoning. Though the findings of this heavy metal poisoning mimicks corrosive acid poisoning, it has to be viewed through the eye of forensic toxicology for a clear view in clinching the diagnosis in the earlier phase of treatment.

Isolation and screening of heavy metal resistant ammonia oxidizing bacteria from soil and waste dump: a potential candidates for bioremediation of heavy metals

ABSTRACTThe study was undertaken to examine the response of ammonia oxidizing bacteria to different heavy metal salt in an elevated concentration. Surface soil samples at depth of 0-15 cm were collected at random from Akwa Ibom State University in Akwa Ibom State, soil sample from University of Nigeria, Nsukka and from solid waste disposal site in Uyo, Akwa Ibom State. The response of heavy metal salt on Ammonia Oxidizing bacteria(AOB) isolated from soil samples were investigated by supplementing different heavy metal salts namely, copper(Cu),nickel (Ni), lead (Pb) and cadmium (Cd) at four loading rates(100,200,500,1000 µg/ml) in mineral salt broth with Ammonia Oxidizing Bacteria (AOB) isolate. The cultures were incubated for 7 days. Growth of AOB was measured by withdrawing samples from the medium every 24 hours and absorbance of the turbidity measured at 600 nanometre using spectrophotometer. All bacteria showed high tendency to decrease optical density while increasing metal concentration in the medium. Tolerance for the metal ions was dependent on concentration, time and the isolate tested. All the Ammonia oxidizing bacterial (AOB) showed a high level of tolerance for the metals tested, and exhibited good growth at all metal salt concentrations tested. These make the nitrifying bacteria attractive potential candidates for further investigations regarding their ability to remove metals from contaminated soil.IMPORTANCEThe aim of this study is tolerance of ammonia oxidizing bacteria growth to heavy metal. Nitrifying bacteria remain a good option for bioremediation of soil and waste dump, since it is regarded as eco-friendly and efficient in biosorption of heavy metal. The study is significant to the field of environmental microbiology by adding to knowledge in bioremediation.

Pretreatment-Integration for Milk Protein Removal and Device-Facilitated Immunochromatographic Assay for 17 Items

Accurate and comprehensive immunochromatographic assay (ICA) data are urgently required in the daily supervision of plants, schools, testing institutions, and law-enforcing departments. Through pretreatment-integration and device-facilitated operation, a quantitative ICA with high sensitivity and throughput was realized on the basis of a commercialized semi-quantitative ICA strip. Three pretreatment methods, namely, acid base, heavy metal salt, and organic solvent methods, have less than three steps. The pretreatment was established for protein removal. A total of 17 pretreated ICA items in milk were considered for the identification of the most suitable pretreatment method. The items are composed of six items pretreated by the acid-base method, six by the heavy salt method, and five by the organic solvent method. Then, the ICA results with pretreatment were compared with those without pretreatment. After pretreatment, the signal intensity increased by 39%, the detection limit decreased to 12%, the half maximal inhibitory concentration decreased to 18%, and the detection range increased fourfold. A device with mixing and centrifugation functions was designed for the pretreatment-related operations. A pre-incubation sampling device was used to facilitate incubation in batch and high-throughput detection. An ICA reader was used. The detection throughput reached 8 samples per batch or 32 samples per hour. The designed devices were printed through 3D printing and rapid prototyping.

Uptake of heavy metal salt solutions by pollen grains of Magnolia × soulangeana (Magnoliaceae)

To investigate the role of the plasmalemmic cord in the pollen grains of members of the Magnoliaceae, anthers of Magnolia × soulangeana Soul.-Bod. were incubated for 1, 2.5, and 5 h in lead and lanthanum salt solutions. Ultrastructural analysis revealed differences in the labelling of the pollen grains with the time of exposure to the heavy metal salt, which is likely related to metal tolerance mechanisms operating in the pollen grains. Within 1 h of treatment, both tracers produced a fine precipitate lining the entire vegetative cell (VC) plasmalemma (including the plasmalemmic cord) as well as the generative cell (GC) plasmalemma. Heavy deposits were not found inside both the VC and the GC. At later times, the amount of heavy deposits increased on the pollen wall surface and, particularly, in the two outer intine layers. Also, heavy deposits were found in membrane-bound cell components of the VC and the GC, but never in the cytosol. In the VC, the cell components more frequently labelled were the protein storage vacuoles. In both pollen cells, multivesicular bodies, dictyosome cisternae, and small vesicles were also labelled. We hypothesize that the latter organelles participate in the metal ions accumulation (end of the trip), together with the protein vacuoles, or in the transport of metal ions to the vacuoles following the endocytotic uptake of these ions. The presence of both coated and uncoated pits and vesicles in the treated and the untreated pollen reinforces the latter hypothesis. Another significant result was that the tracers, after diffusing through the microchannels in the exine and crossing the intine layers, moved through the plasmalemmic cord to reach the GC periplasm. We suggest that the plasmalemmic cord may provide a system of communication for the flux of solutes from the anther loculus to both pollen cells and (or) from the VC to the GC.Key words: pollen grain, ultrastructure, metal uptake, metal tolerance, lead nitrate, lanthanum nitrate.