Toxicity of Heavy Metals and Recent Advances in Their Removal: A Review.

Natural and anthropogenic sources of metals in the ecosystem are perpetually increasing; consequently, heavy metal (HM) accumulation has become a major environmental concern. Human exposure to HMs has increased dramatically due to the industrial activities of the 20th century. Mercury, arsenic lead, chrome, and cadmium have been the most prevalent HMs that have caused human toxicity. Poisonings can be acute or chronic following exposure via water, air, or food. The bioaccumulation of these HMs results in a variety of toxic effects on various tissues and organs. Comparing the mechanisms of action reveals that these metals induce toxicity via similar pathways, including the production of reactive oxygen species, the inactivation of enzymes, and oxidative stress. The conventional techniques employed for the elimination of HMs are deemed inadequate when the HM concentration is less than 100 mg/L. In addition, these methods exhibit certain limitations, including the production of secondary pollutants, a high demand for energy and chemicals, and reduced cost-effectiveness. As a result, the employment of microbial bioremediation for the purpose of HM detoxification has emerged as a viable solution, given that microorganisms, including fungi and bacteria, exhibit superior biosorption and bio-accumulation capabilities. This review deals with HM uptake and toxicity mechanisms associated with HMs, and will increase our knowledge on their toxic effects on the body organs, leading to better management of metal poisoning. This review aims to enhance comprehension and offer sources for the judicious selection of microbial remediation technology for the detoxification of HMs. Microbial-based solutions that are sustainable could potentially offer crucial and cost-effective methods for reducing the toxicity of HMs.

Exploring the potential of Cinnamomum zeylanicum oil against drug resistant Helicobacter pylori-producing cytotoxic genes.

Thirty-one of sixty dyspeptic patients tested positive for Helicobacter pylori colonization in this study, as determined by histopathology and 16S rRNA. The cytotoxin-associated gene A (cagA) and vacuolating cytotoxin A (vacA) genes were found in 67.7 and 93.5% of H. pylori patients, respectively. The cagA gene was found to be associated with 100% of patients with duodenal erosion and ulceration identified via endoscopy examination. In addition, 86.7% of patients with cancerous and precancerous lesions, glandular atrophy, and intestinal metaplasia identified via histopathology examination. The vacA s1m1 mutation was associated with more severe forms of gastric erosion and ulceration, as well as the presence of precancerous and cancerous lesions. Eighteen (64.3%) of the twenty-eight isolates were classified as multi-drug resistant (MDR) or pan-drug resistant (PDR) H. pylori. Due to a resurgence of interest in alternative therapies derived from plants as a result of H. pylori resistance to the majority of commonly used antibiotics, the inhibitory activity of five essential oils extracted from some commonly used medicinal plants was evaluated in vitro against drug-resistant H. pylori clinical isolates. Cinnamomum zeylanicum essential oil demonstrated the highest anti-H. pylori activity when compared to the other essential oils tested. Cinnamaldehyde was the most abundant compound in C. zeylanicum (65.91%). The toxicological evaluation established the safety of C. zeylanicum oil for human use. As a result, C. zeylanicum essential oil may represent a novel antibacterial agent capable of combating drug-resistant H. pylori carrying cytotoxin genes.

Clinicopathological characteristics and outcomes of eosinophilic cystitis: A retrospective study.

BACKGROUND: Eosinophilic cystitis (EC) is a rare inflammatory urinary bladder disorder whose etiology, pathogenesis, and treatment are unknown. The work aims to evaluate the clinical manifestations, cystoscopic characteristics, pathological features, treatment, and clinical outcome of EC patients. MATERIALS AND METHODS: The clinical records and histopathology material of 22 patients diagnosed as EC during ten years were reviewed and analyzed for patient's age, sex, clinical data, cystoscopic features, biopsy procedures, treatment plan, follow-up, and prognosis. Frequencies, normality tests, descriptive statistics, and correlations were run. RESULTS: The mean age of patients was 46.5 + 17 years, 12 females and 10 males. Regarding the patient's complaints, dysuria was the most frequent main symptom, followed by hematuria. On cystoscopic examination, bladder mass was seen in 54.5% of patients. Six patients (27.3%) were associated with different allergic diseases; however peripheral eosinophilia was shown in two patients (9.1%). All cases revealed predominance of eosinophilic infiltration on microscopic examination. The most commonly used medications were corticosteroids for 72.7% of patients with tapering dose giving a significant improvement with a recorded recurrence in one patient after 12 months from the first lesion. CONCLUSIONS: No specific clinical presentation for EC patients and histopathology is the standard diagnostic tool. Medical treatment including corticosteroids was the first line with good prognosis, although recurrence remains a possibility which emphasizes the importance of patients' follow-up.

The Importance of Nitric Oxide as the Molecular Basis of the Hydrogen Gas Fumigation-Induced Alleviation of Cd Stress on Ganoderma lucidum.

Whether or not hydrogen gas (H2) can reduce cadmium (Cd) toxicity in Ganoderma lucidum has remained largely unknown. Here, we report that Cd-induced growth inhibition in G. lucidum was significantly alleviated by H2 fumigation or hydrogen-rich water (HRW), evaluated by lower oxidative damage and Cd accumulation. Moreover, the amelioration effects of H2 fumigation were better than of HRW in an optimum concentration of H2 under our experimental conditions. Further results showed that H2-alleviated growth inhibition in G. lucidum was accompanied by increased nitric oxide (NO) level and nitrate reductase (NR) activity under Cd stress. On the other hand, the mitigation effects were reversed after removing endogenous NO with its scavenger cPTIO or inhibiting H2-induced NR activity with sodium tungstate. The role of NO in H2-alleviated growth inhibition under Cd stress was proved to be achieved through a restoration of redox balance, an increase in cysteine and proline contents, and a reduction in Cd accumulation. In summary, these results clearly revealed that NR-dependent NO might be involved in the H2-alleviated Cd toxicity in G. lucidum through rebuilding redox homeostasis, increasing cysteine and proline levels, and reducing Cd accumulation. These findings may open a new window for H2 application in Cd-stressed economically important fungi.

Syzygium aromaticum L.: Traditional herbal medicine against cagA and vacA toxin genes-producing drug resistant Helicobacter pylori.

The Pan-Drug Resistant (PDR), Helicobacter pylori remains an intractable challenge in public health worldwide and this pathogenicity is mainly due to the presence of a cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA). On the other hand, plant extracts such as Syzygium aromaticum contain a diverse array of secondary metabolites, which could be potentially used to combat H. pylori pathogens. To our knowledge, this is the first report on the biomedical potential of S. aromaticum extract against cytotoxin-associated genes producing PDR H. pylori. In this investigation, out of 45 gastric antral biopsy specimens of dyspeptic patients, 20 strains were confirmed as H. pylori. Eight (40%) out of 20 strains were PDR H. pylori while the rest of the strains were Multi-Drug Resistant (MDR) strains. Genotypic analyses of PDR H. pylori strains showed that cagA and vacA genes were found to be 75% and 87.5%, respectively and m2s2 was the most common subtype of vacA gene. S. aromaticum showed a significant higher anti-H. pylori activity compared to that of Cinnamomum zeylanicum and Thymus vulgaris. Eugenol was the major phenolic compound (28.14%) detected in the methanolic extract of S. aromaticum. Clearly, results of the toxicological assessment confirmed the safety of S. aromaticum for use. Hence, these results suggest that S. aromaticum could be a new useful natural antimicrobial agent that could potentially combat cytotoxin genes-producing drug-resistant H. pylori. Moreover, these findings provide a scientific basis for the development of antimicrobial agents from traditional herbal medicines for gastroprotection against gastric ulcer.