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Superparamagnetic iron oxide nanoparticles are well known for biomedical applications. The particle size, morphology, surface area, and functionalization are the key parameters that affect their bioactivity properties. Inline to this, the superparamagnetic Fe3O4 nanoparticles were prepared via chemical coprecipitation method with an average particle size of 6 ± 3 nm. The particles were surface-functionalized with chitosan and in-house prepared reduced graphene oxide (rGO) to obtain chitosan-coated Fe3O4 nanoparticles (C-Fe3O4) and rGO-Fe3O4 nanocomposites (G-Fe3O4), respectively. Upon functionalization, the physicochemical properties of the materials were characterized thoroughly using X-ray diffraction, transmission electron microscopy, vibrating sample magnetometer, Raman Spectroscopy, and thermal gravimetric analysis. Furthermore, they have subjected to cytotoxicity assay, agar two-fold broth dilution test, and disc diffusion assay experiments for the determination of cytotoxicity and antibacterial activities. The effect of surface functionalization on their bioactivity was investigated thoroughly. The surface functionalization with chitosan and rGO has enhanced the bioactivity of the Fe3O4 nanoparticles.
Recently, we introduced an epoxy group to mebendazole by a reaction with epichlorohydrin and obtained two isoforms, mebendazole C1 (M-C1) and mebendazole C2 (M-C2). The in vitro effects of mebendazole derivatives at different concentrations on Echinococcus multilocularis protoscoleces and metacestodes as well as cytotoxicity in rat hepatoma (RH) cells were examined. The results demonstrated that the solubility of the two derivatives was greatly improved compared to mebendazole. The mortality of protoscoleces in vitro reached to 70–80% after 7 days of exposure to mebendazole or M-C2, and M-C2 showed higher parasiticidal effects than mebendazole (P > 0.05). The parasiticidal effect of M-C1 was low, even at a concentration of 30 µm. The percentage of damaged metacestodes that were treated with mebendazole and M-C2 in vitro at different concentrations were similar, and M-C1 exhibited insignificant effects on metacestodes. Significant morphological changes on protoscoleces and metacestodes were observed after treatment with mebendazole and M-C2. In addition, the introduction of an epoxy group to mebendazole also reduced its cytotoxicity in RH cells. Our results demonstrate that the introduction of an epoxy group not only improved the solubility of mebendazole, but also increased its parasiticidal effects on E. multilocularis and reduced its cytotoxicity in RH cells.
Trichomonas vaginalis induces cellular damage to the host cells (cytotoxicity) through the proteolytic activity of multiple proteinases of the cysteine type (CPs). Some CPs are modulated by environmental factors such as iron, zinc, polyamines, etc. Thus, the goal of this study was to assess the effect of glucose on T. vaginalis cytotoxicity, proteolytic activity and the particular role of TvCP2 (TVAG_057000) during cellular damage. Cytotoxicity assays showed that glucose-restriction (GR) promotes the highest HeLa cell monolayers destruction (~95%) by trichomonads compared to those grown under high glucose (~44%) condition. Zymography and Western blot using different primary antibodies showed that GR increased the proteolytic activity, amount and secretion of certain CPs, including TvCP2. We further characterized the effect of glucose on TvCP2. TvCP2 increases in GR, localized in vesicles close to the plasma membrane and on the surface of T. vaginalis. Furthermore, pretreatment of GR-trichomonads with an anti-TvCP2r polyclonal antibody specifically reduced the levels of cytotoxicity and apoptosis induction to HeLa cells in a concentration-dependent manner. In conclusion, our data show that GR, as a nutritional stress condition, promotes trichomonal cytotoxicity to the host cells, increases trichomonad proteolytic activity and amount of CPs, such as TvCP2 involved in cellular damage.
Local chemotherapy with biocompatible drug-delivery systems prolongs survival in patients. Due to the biocompatibility and high loading capacity, bentonite nanoclay is a good candidate for the fabrication of drug-delivery vehicles. In this study, doxorubicin-bentonite nanoclay complex (DOX-Bent complex) was prepared for the first time as a sustained-release drug-delivery system for intratumoural chemotherapy of melanoma. An efficient loading of DOX on 1 mg of bentonite nanoclay as high as 994.45 ± 4.9 µg was obtained at a 30:1 DOX:bentonite nanoclay mass ratio. The DOX-Bent complex showed a low initial burst release of DOX in the first 24 h of release, followed by a sustained-release pattern for 21 days. The cumulative in vitro release of DOX from the DOX-Bent complex at pHs 6.5 and 7.4 revealed that the DOX-Bent complex can distinguish between tumour and normal tissues and express specific drug release at the tumour site. The results of cytotoxicity experiments indicated that the release pattern of DOX can supply sufficient DOX to inhibit growth of the melanoma cancer cell with an IC50 of 0.29 ± 0.07 µg/mL. It is thus suggested that the DOX-Bent complex be introduced as a drug-delivery system for effective local cancer therapy.
Shiga toxin-producing Escherichia coli (STEC) is a known food pathogen, which main reservoir is the intestine of ruminants. The abundance of different STEC lineages in nature reflect a heterogeneity that is characterised by the differential expression of certain genotypic characteristics, which in turn are influenced by the environmental conditions to which the microorganism is exposed. Bacterial homeostasis and stress response are under the control of the alarmone guanosine tetraphosphate (ppGpp), which intrinsic levels varies across the E. coli species. In the present study, 50 STEC isolates from healthy sheep were evaluated regarding their ppGpp content, cytotoxicity and other relevant genetic and phenotypic characteristics. We found that the level of ppGpp and cytotoxicity varied considerably among the examined strains. Isolates that harboured the stx2 gene were the least cytotoxic and presented the highest levels of ppGpp. All stx2 isolates belonged to phylogroup A, while strains that carried stx1 or both stx1 and stx2 genes pertained to phylogroup B1. All but two stx2 isolates belonged to the stx2b subtype. Strains that belonged to phylogroup B1 displayed on average low levels of ppGpp and high cytotoxicity. Overall, there was a negative correlation between cytotoxicity and ppGpp.
The synthesis and antiprotozoal activity of some simple dialkyl pyrazole-3,5-dicarboxylates (compounds 2–6) and their sodium salts (pyrazolates) (compounds 7–9) against Trypanosoma cruzi, Leishmania infantum and Leishmania braziliensis are reported. In most cases the studied compounds showed, especially against the clinically significant amastigote forms, in vitro activities higher than those of the reference drugs (benznidazole for T. cruzi and glucantime for Leishmania spp.); furthermore, the low non-specific cytotoxicities against Vero cells and macrophages shown by these compounds led to good selectivity indexes, which are 8–72 times higher for T. cruzi amastigotes and 15–113 times higher for Leishmania spp. amastigotes than those of the respective reference drugs. The high efficiency of diethyl ester 3 and its sodium salt 8 against the mentioned protozoa was confirmed by further in vitro assays on infection rates and by an additional in vivo study in a murine model of acute and chronic Chagas disease. The inhibitory capacity of compounds 3 and 8 on the essential iron superoxide dismutase of the aforementioned parasites may be related to the observed anti-trypanosomatid activity. The low acute toxicity of compounds 3 and 8 in mice is also reported in this article.
Resin composite materials that are used to restore tooth cervical lesions associated with gingival recessions can hamper healing after root coverage surgeries. This study evaluates the in vitro cytotoxic effect of five resin composites (two commercial and three experimental) on oral mesenchymal stem cells (MSCs) and the persistence of stemness properties in high passage MSCs. Sorption and solubility tests were made for all materials. MSCs were isolated from re-entry palatal and periodontal granulation tissues and were characterized and cultured on composite discs. Cytotoxicity of the materials was evaluated by the Alamar Blue viability test, by Paul Karl Horan (PKH) labeling, and by immunocytochemical staining for actin. Water and saliva sorption and solubility data revealed that two of the experimental materials behaved comparable with the marketed resin composites. The Alamar Blue viability test shows that both cell lines grew well on composite discs that seemed to induce no apparent toxic effects. No signs of disruption of cytoskeleton organization was seen. Experimental resin composites can be recommended for further investigation for obtaining approval for use. The standard minimal criteria were fulfilled for high passage MSCs. Palatal tissue regains its regenerative properties in terms of MSC presence in the re-entry area after 6 months of healing.
Coronatin-2, a 14.5 kDa protein, was isolated from culture filtrates of the entomopathogenic fungus Conidiobolus coronatus (Costantin) Batko (Entomophthoramycota: Entomophthorales). After LC–MS/MS (liquid chromatography tandem mass spectrometry) analysis of the tryptic peptide digest of coronatin-2 and a mass spectra database search no orthologs of this protein could be found in fungi. The highest homology was observed to the partial translation elongation factor 1a from Sphaerosporium equinum (protein sequence coverage, 21%), with only one peptide sequence, suggesting that coronatin-2 is a novel fungal protein that has not yet been described. In contrast to coronatin-1, an insecticidal 36 kDa protein, which shows both elastolytic and chitinolytic activity, coronatin-2 showed no enzymatic activity. Addition of coronatin-2 into cultures of hemocytes taken from larvae of Galleria mellonella Linnaeus (Lepidoptera: Pyralidae), resulted in progressive disintegration of nets formed by granulocytes and plasmatocytes due to rapid degranulation of granulocytes, extensive vacuolization of plasmatocytes accompanied by cytoplasm expulsion, and cell disintegration. Spherulocytes remained intact, while oenocytes rapidly disintegrated. Coronatin-2 produced 80% mortality when injected into G. mellonella at 5 µg larva−1. Further study is warranted to determine the relevance of the acute toxicity of coronatin-2 and its effects on hemocytes in vitro to virulence of C. coronatus against its hosts.
Biocompatibility testing of new materials is often performed in vitro by measuring the growth rate of mammalian cancer cells in time-lapse images acquired by phase contrast microscopes. The growth rate is measured by tracking cell coverage, which requires an accurate automatic segmentation method. However, cancer cells have irregular shapes that change over time, the mottled background pattern is partially visible through the cells and the images contain artifacts such as halos. We developed a novel algorithm for cell segmentation that copes with the mentioned challenges. It is based on temporal differences of consecutive images and a combination of thresholding, blurring, and morphological operations. We tested the algorithm on images of four cell types acquired by two different microscopes, evaluated the precision of segmentation against manual segmentation performed by a human operator, and finally provided comparison with other freely available methods. We propose a new, fully automated method for measuring the cell growth rate based on fitting a coverage curve with the Verhulst population model. The algorithm is fast and shows accuracy comparable with manual segmentation. Most notably it can correctly separate live from dead cells.
Some lactic acid bacteria play an important role in the immune system with potential benefits to the host. However, detailed mechanisms of immune modulation exerted by probiotics remain to be clarified. Since immune response changes in a time-related manner in some cases, we monitored changes in mRNA levels in the spleen of mice during 14 d feeding with Lactobacillus brevis KB290 (KB290). Female BALB/c mice, aged 9 weeks, commenced a diet containing KB290 (3 × 109colony-forming units/g) or starch for a period of 1, 4, 7 or 14 d. Cytotoxic activity of the resulting splenocytes against YAC-1 cells was measured using flow cytometry. The activity was found to be significantly higher in the treated group on days 1 and 7. The highest activity appeared on day 4, but was not statistically significantly different. Gene expression profiles were analysed using DNA microarray. Gene Ontology (GO) terms related to the immune process were significantly enriched in the up-regulated gene set on days 1, 4 and 7, and GO terms related to the cellular process were enriched in the down-regulated gene set on days 4 and 7. Although the up-regulated genes involved in antigen processing and presentation for stimulation of CD8+ cytotoxic T cells were not observed on day 14, some genes involved in T-cell and natural killer cell activation remained up-regulated until day 14. For the majority of the genes tested, RT-PCR analysis was used to verify the results obtained from the DNA microarray analysis. The sequential gene expression profiling reflected changes in cytotoxic activity during KB290 feeding.
Lactic acid bacteria confer a variety of health benefits. Here, we investigate the mechanisms by which Lactobacillus brevis KB290 (KB290) enhances cell-mediated cytotoxic activity. Female BALB/c mice aged 9 weeks were fed a diet containing KB290 (3 × 109 colony-forming units/g) or starch for 1 d. The resulting cytotoxic activity of splenocytes against YAC-1 cells was measured using flow cytometry and analysed for gene expression using DNA microarray technology. KB290 enhanced the cell-mediated cytotoxic activity of splenocytes. DNA microarray analysis identified 327 up-regulated and 347 down-regulated genes that characterised the KB290 diet group. The up-regulated genes were significantly enriched in Gene Ontology terms related to immunity, and, especially, a positive regulation of T-cell-mediated cytotoxicity existed among these terms. Almost all the genes included in the term encoded major histocompatibility complex (MHC) class I molecules involved in the presentation of antigen to CD8+ cytotoxic T cells. Marco and Signr1 specific to marginal zone macrophages (MZM), antigen-presenting cells, were also up-regulated. Flow cytometric analysis confirmed that the proportion of MZM was significantly increased by KB290 ingestion. Additionally, the over-represented Kyoto Encyclopedia of Genes and Genomes pathways among the up-regulated genes were those for natural killer (NK) cell-mediated cytotoxicity and antigen processing and presentation. The results for the selected genes associated with NK cells and CD8+ cytotoxic T cells were confirmed by quantitative RT-PCR. These results suggest that enhanced cytotoxic activity could be caused by the activation of NK cells and/or of CD8+ cytotoxic T cells stimulated via MHC class I presentation.
This paper reports the effects of BnSP-7 toxin, a catalytically inactive phospholipase A2 from Bothrops pauloensis snake venom, on Leishmania (Leishmania) amazonensis. BnSP-7 presented activity against promastigote parasite forms both in the MTT assay, with IC50 of 58·7 μg mL−1 of toxin, and a growth curve, inhibiting parasite proliferation 60–70% at concentrations of 50–200 μg mL−1 of toxin 96 h after treatment. Also, the toxin presented effects on amastigotes, reducing parasite viability by 50% at 28·1 μg mL−1 and delaying the amastigote–promastigote differentiation process. Ultrastructural studies showed that BnSP-7 caused severe morphological changes in promastigotes such as mitochondrial swelling, nuclear alteration, vacuolization, acidocalcisomes, multiflagellar aspects and a blebbing effect in the plasma membrane. Finally, BnSP-7 interfered with the infective capacity of promastigotes in murine peritoneal macrophages, causing statistically significant infectivity-index reductions (P < 0·05) of 20–35%. These data suggest that the BnSP-7 toxin is an important tool for the discovery of new parasite targets that can be exploited to develop new drugs for treating leishmaniasis.
Besides being cholesterol-lowering agents, phytosterols (PS) can inhibit the growth and development of tumours. The anti-neoplastic activity is accounted for by PS incorporation into cell membranes, resulting in the interference of membrane functionality. The similarity between the PS cholesterol-lowering and anti-neoplastic effective doses deserves attention on the possible adverse effects even in non-neoplastic cells. To date, few studies have addressed the clarification of this important issue. In the present study, we supplemented primary, non-neoplastic neonatal rat cardiomyocytes with two different PS concentrations (3 or 6 μg/ml), both within the range of human plasma concentration. Cardiac cells were chosen as an experimental model since the heart has been reported as the target organ for subchronic toxicity of PS. Following supplementation, a dose-dependent incorporation of PS and a decrease in cholesterol content were clearly evidenced. PS did not induce apoptosis but caused a reduction in metabolic activity (measured as 3-(4,5-dimethyldiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) conversion) and a slowing down of cell growth. The lower MTT conversion and the similar lactate dehydrogenase release could suggest that PS more efficiently target mitochondria than plasma membrane integrity. The replacement of cholesterol by PS could also have caused the observed slowing down of cell growth and the reduction in metabolic activity, which could rely on the PS increase, cholesterol decrease, or both. The present study is the first report on the effect of PS in cardiac cells, and although it is difficult to translate the obtained results to the health of heart tissue, it raises concerns about the safety of long-term exposure to physiologically relevant PS concentrations.
Konjac glucomannan (KGM) has been shown to increase human colon microbial ecology and reduce faecal toxicity in mice. The main goal of the present study was to assess the effects of a KGM supplement into a low-fibre diet on precancerous markers of colon cancer in a double-blind, placebo- and diet-controlled study. Adult volunteers consumed defined diets supplemented with konjac (4·5 g/d) or placebo (maize starch) for 4 weeks. Stools collected before and at the end of the supplementation were analysed for β-glucosidase, β-galactosidase and β-glucuronidase activities, microflora and bile acids. Faecal water was co-incubated with Caco-2 cells, a model of human colonocytes, to determine the cytotoxicity and DNA-damaging effect as assessed by the comet assay. The results indicated that the KGM supplement significantly decreased faecal β-glucuronidase activity by 25·6 (se 7·8) % and faecal secondary bile acid level by 42·4 (se 11·8) %. In contrast, consuming the defined diet supplemented with placebo for 4 weeks did not improve these determinants. The KGM-supplemented diet, but not the placebo diet, significantly increased the survival rate (%) of Caco-2 cells co-incubated with faecal water for 1 and 3 h, respectively. In addition, KGM significantly reduced the DNA damage induced by the faecal water alone or in combination with H2O2. The faecal bifidobacteria and lactobacilli levels increased only with the KGM-supplemented diet. Therefore, we conclude that supplementation of KGM into a low-fibre diet improved the faecal microbial ecology and metabolites, which may contribute to the reduced toxicity of faecal water and precancerous risk factors of human colon cancer.
The ability of pathogens to neutralize host defence mechanisms represents a fundamental requisite in the successful establishment of an infection. Host-pathogen interactions between quahog parasite unknown (QPX) and its hard clam host are poorly understood. Our prior in vivo investigations have shown that different QPX isolates display varying levels of pathogenicity toward clams. Similarly, field investigations and laboratory transmission studies revealed some variations in the susceptibility of different hard clam stocks to QPX infection. An in vitro approach was developed in this study to evaluate the toxicity of QPX cells and extracellular products toward haemocytes using a neutral red uptake assay. Results demonstrated that QPX produces virulence factors that are cytotoxic to M. mercenaria haemocytes. This cytotoxicity appears to be induced by clam factors, suggesting that it may play an important role in supporting QPX infection and proliferation within the host. Moreover, application of this technique to different QPX isolates and clam broodstocks indicates variations of QPX cytotoxicity in agreement with previous in vivo experiments, strengthening the existence of different QPX strains.
Oxysterols arise from the enzymic or non-enzymic oxidation of cholesterol and have been shown to be cytotoxic to certain cell lines. In particular, apoptosis induced by the oxysterol 7β-hydroxycholesterol (7β-OH) has been associated with the generation of oxidative stress, cytochrome c release and caspase activation. Due to the fundamental importance of apoptosis in pathological processes, the identification of substances capable of modulating this form of cell death is now actively researched. The objective of the present study was to investigate if apigenin, lycopene and astaxanthin could inhibit 7β-OH-induced apoptosis in U937 cells. Pretreatment with 0·1 μm-astaxanthin protected against apoptosis, while lycopene did not oppose the adverse effects of 7β-OH. At low concentrations, apigenin did not protect against oxysterol-induced apoptosis; however, at higher concentrations it intensified cell death. Additionally, we investigated the effect of 7β-OH, apigenin and astaxanthin on the activation of the serine threonine kinase Akt (phosphorylated Akt:Akt ratio) to determine whether the effect on cell viability and growth was linked to the Akt signalling pathway. Akt activation was decreased in the oxysterol-treated cells compared with control cells; however, this did not attain significance. Interestingly, activation of Akt was significantly reduced compared with control cells following incubation with apigenin and astaxanthin both in the absence and in the presence of 7β-OH. Our data suggest that apigenin, lycopene and astaxanthin failed to protect against 7β-OH-induced apoptosis, and the decrease in cell viability and the increase in apoptotic nuclei induced by the antioxidants appear to be associated with down regulation of Akt activity.
Fructo-oligosaccharides (FOS) are widely used in commercial food products. Most studies on FOS concern the health benefits, but some negative effects were recently reported concerning thefaecal cytotoxicity and excretion of mucin-type oligosaccharides in combination with a Ca-restricted diet. The present study was performed to investigate whether these effects of FOS are observed in adults consuming a regular diet unrestricted in Ca. The study was a randomised, double-blind, placebo-controlled crossover trial, involving eleven healthy adults, who consumed 25–30g FOS or maltodextrin (control) in a random order for 2 weeks in addition to their regular diet. Stools were collected for analysis of pH and SCFA (as markers of fermentation), for the assessment of faecal water cytotoxicity, and for the analysis of alkaline phosphataseactivity (as a marker of epithelial cell turnover) andO-linked oligosaccharides (to estimate the excretion of mucin-type oligosaccharides). FOS consumption significantly altered bacterial fermentation (increased percentage of acetate, decreased percentage of butyrate) and tended to decrease stool pH. Furthermore, FOS consumption resulted in a significantly higher stool frequency and in significantly more complaints of flatulence. No significant differences between the control and FOS period were observed in the mean cytotoxicity of faecal water (37·5 (sem 6·9) % v. 18·5 (sem 6·9) % P=0·084), in mean alkaline phosphatase activity (27·7 (sem 2·9) v. 24·6 (sem 3·2) U/g dry faeces; P=0·496) or in the mean excretion of mucin-type oligosaccharides (49·9 (sem 4·0)v. 53·5 (sem 4·3) mg/g dry faeces; P=0·553). We conclude that dietary FOS in a dose up to 25–30g/d altered the bacterial fermentation pattern but did not affect faecal cytotoxicity or the faecal concentration of mucin-type oligosaccharides in human adults consuming a regular diet.
Phytosterols contain an unsaturated ring structure and therefore are susceptible to oxidation under certain conditions. Whilst the cytotoxicity of the analogous cholesterol oxidation products (COP) has been well documented, the biological effects of phytosterol oxidation products (POP)have not yet been fully ascertained. The objective of the present study was to examine the cytotoxicity of β-sitosterol oxides and their corresponding COP in a human monocytic cell line (U937), a colonic adenocarcinoma cell line (CaCo-2) and a hepatoma liver cell line (HepG2). 7β-Hydroxysitosterol, 7-ketositosterol, sitosterol-3β,5α,6β-triol and a sitosterol-5α,6α-epoxide–sitosterol-5β,6β-epoxide (6:1) mixture were found to be cytotoxic to all three cell lines employed; the mode of cell death was by apoptosis in the U937 cell line and necrosis in the CaCo-2 and HepG2 cells. 7β-Hydroxysitosterol was the only β-sitosterol oxide to cause depletion in glutathione, indicating that POP-induced apoptosis may not be dependent on the generation of an oxidative stress. A further objective of this study was to assess the ability of the antioxidants α-tocopherol, γ-tocopherol and β-carotene to modulate POP-induced cytotoxicity in U937 cells. Whilst α/γ-tocopherol protected against 7β-hydroxycholesterol-induced apoptosis, they did not confer protection against 7β-hydroxysitosterol-or 7-ketositosterol-induced toxicity, indicating that perhaps COP provoke different apoptotic pathways than POP. β-Carotene did not protect against COP- or POP-induced toxicity. In general, results indicate that POP have qualitatively similar toxic effects to COP. However, higher concentrations of POP are required to elicit comparable levels of toxicity.
We have previously demonstrated that during pregnancy there exists an increased parasiticide activity against Trichinella spiralis newborn larvae (NBL) in infected rats. In this work we analysed the contribution of peritoneal cells from non-infected pregnant rats to the mortality of the NBL in cytotoxicity assays, and evaluated the role of progesterone in this effector mechanism. Our findings suggest that progesterone can induce activation of effector peritoneal cells to destroy the NBL in a rapid and antibody-independent manner. The administration of progesterone to ovariectomized rats also led to a significant decrease in the parasite load of the animals, thus demonstrating that progesterone induces the increase of the parasiticide activity of the leukocytes involved in the mechanisms of NBL death.
The intracellular distribution of the elements carbon, nitrogen, and
oxygen was measured in cultured rat hepatocytes by energy dispersive
electron probe X-ray microanalysis of 100-nm-thick freeze-dried
cryosections. Electron irradiation with a dose up to 106
e/nm2 caused no or merely negligible mass loss in
mitochondria and in cytoplasm. Cell nuclei lost carbon, nitrogen,
and—to a clearly higher extent—oxygen with increasing
electron irradiation. Therefore, electron doses less than 3 ×
105 e/nm2 were used to measure the
subcellular compartmentation of carbon, nitrogen, and oxygen in
cytoplasm, mitochondria, and nuclei of the cells. The subcellular
distribution of carbon, nitrogen, and oxygen reflects the intracellular
compartmentation of various biomolecules. Cells exposed to inorganic
mercury before cryofixation showed an increase of oxygen in nuclei and
cytoplasm. Concomitantly the phosphorus/nitrogen ratio decreased in
mitochondria. The data suggest mercury-induced production of
ribonucleic acid (RNA) and decrease of adenosine triphosphate (ATP).
Although biomolecules cannot be identified by X-ray microanalysis,
measurements of the whole element spectrum including the light elements
carbon, nitrogen, and oxygen can be useful to study specific
biomolecular activity in cellular compartments depending on the
functional state of the cell.