Mn accumulation in a submerged plant Egeria densa (Hydrocharitaceae) is mediated by epiphytic bacteria.

Many aquatic plants act as biosorbents, removing and recovering metals from the environment. To assess the biosorbent activity of Egeria densa, a submerged freshwater macrophyte, plants were collected monthly from a circular drainage area in Lake Biwa basin and the Mn concentrations of the plants were analysed. Mn concentrations in these plants were generally above those of terrestrial hyperaccumulators, and were markedly higher in spring and summer than in autumn. Mn concentrations were much lower in plants incubated in hydroponic medium at various pH levels with and without Mn supplementation than in field-collected plants. The precipitation of Mn oxides on the leaves was determined by variable pressure scanning electron microscopy-energy dispersive X-ray analysis and Leucoberbelin blue staining. Several strains of epiphytic bacteria were isolated from the field-collected E. densa plants, with many of these strains, including those of the genera Acidovorax, Comamonas, Pseudomonas and Rhizobium, found to have Mn-oxidizing activity. High Mn concentrations in E. densa were mediated by the production of biogenic Mn oxide in biofilms on leaf surfaces. These findings provide new insights into plant epidermal bacterial flora that affect metal accumulation in plants and suggest that these aquatic plants may have use in Mn phytomining.

Case of streptococcal toxic shock syndrome caused by rapidly progressive group A hemolytic streptococcal infection during postoperative chemotherapy for cervical cancer.

Streptococcal toxic shock syndrome (STSS) is a severe infectious disease caused by group A hemolytic streptococcus (Streptococcus pyogenes). This condition is a serious disease that involves rapidly progressive septic shock. We experienced a case of STSS caused by primary peritonitis during treatment with paclitaxel and cisplatin (TP therapy) as postoperative chemotherapy for cervical cancer. STSS mostly develops after extremity pain, but initial influenza-like symptoms of fever, chill, myalgia and gastrointestinal symptoms may also occur. TP therapy is used to treat many cancers, including gynecological cancer, but may cause adverse reactions of neuropathy and nephrotoxicity and sometimes fever, arthralgia, myalgia, abdominal pain and general malaise. The case reported here indicates that development of STSS can be delayed after chemotherapy and that primary STSS symptoms may be overlooked because they may be viewed as adverse reactions to chemotherapy. To our knowledge, this is the first report of a case of STSS during chemotherapy.