Severe toxic effects of low-dose methotrexate treatment for placenta accreta in a patient with methylenetetrahydrofolate reductase mutations.

WHAT IS KNOWN AND OBJECTIVE: Low-dose methotrexate (LDMTX) has been widely used for many decades in clinical settings, with good safety profiles compared with those of high-dose methotrexate. LDMTX is also used as one of the off-label conservative therapies in treating placenta accreta (PA). Until now, only a few mild adverse drug reactions (ADRs) have been published after short-term use of LDMTX, and no severe cases have been reported. CASE SUMMARY: We present a case of a 30-year-old female who developed acute severe oral ulcerative mucositis with degree IV myelosuppression and degree III hepatic injury, after three doses of LDMTX to treat placenta accrete. The symptoms gradually improved after leucovorin rescue and supportive treatments. WHAT IS NEW AND CONCLUSION: The present case provides the first severe ADR report for the short-term use of LDMTX for treating PA, indicating that potentially life-threatening complications can also occur when using LDMTX. Early recognition and immediate leucovorin rescue could result in a favourable outcome.

In vitro and in vivo chemo-phototherapy of magnetic TiO2 drug delivery system formed by pH-sensitive coordination bond.

To achieve tumor-specific delivery of doxorubicin, TiO2@Fe3O4/PEI/delivery of doxorubicin conjugates were designed and synthesized. Fe3O4 could act as magnetically responsive carriers and enhance the visible light photodynamic activities of TiO2 Delivery of doxorubicin was conjugated via coordination bond. The drug release rate at pH 5.2 was much faster than that at pH 7.4, due to pH-sensitive coordination bond. Besides, TiO2@Fe3O4/PEI/delivery of doxorubicin showed high antitumor efficacy combining with phototherapy, good bio-safety, higher cellular uptake with an external magnetic field, and less toxicity in vitro and in vivo. These results suggested that TiO2@Fe3O4/PEI/delivery of doxorubicin may be promising for high tumor treatment efficacy with minimal side effects in future.

[Isolation and identification of cultivable myxobacteria in the rhizosphere soils of medicinal plants].

OBJECTIVE: We isolated myxobacteria and explored their diversity from the rhizosphere soils of some medicinal plants. METHODS: We used the helper bacteria baiting technique to isolate myxobacteria from the rhizosphere soils collected in South China Botanical Garden and Nanling National Forest Park. The myxobacteria were identified by morphological characteristics and 16S rDNA gene sequences analysis. RESULTS: A total of 50 strains were isolated from 22 soil samples, which were identified into 7 genera, Myxococcus (18), Corallococcus (11), Cystobacter (7), Archangium (8), Stigmatella (1), Chondromyces (4) and Pyxidicoccus (1). The dominant genera were Myxococcus and Corallococcus. CONCLUSION: Environmental factors were associated with the diversity of myxobactria. Myxobacteria better adapt in high organic matter content and neutral pH environments. The strains of Myxococcus and Corallococcus had a good adaptability for different pH. Meanwhile, the dependence of the strains of Myxococcus and Cystobacter on organic carbon content was not too obvious, and they can also be found in the poor soils. Our findings provided an important scientific base for the development and utilization of myxobacteria resources.

[Association of phytoplasma with Bermuda grass white-leaf disease].

OBJECTIVE: Bermuda grass white leaf is an important disease on Bermuda grass all over the world. The aim of this research is to identify the pathogen which leads to Bermuda grass white leaf occurring on the Chinese mainland. METHODS: PCR amplification technique, sequence analysis and Southern hybridization were used. RESULTS: A 1.3 kb fragment was amplified by PCR phytoplasma universal primers and total DNA sample extracted from ill Bermuda grass as the amplified template. Sequence analysis of the amplified fragment indicated it clustered into Candidatus Phytoplasm Cynodontis. Southern hybridization analysis showed differential cingulums. CONCLUSION: The pathogen of Bermuda grass white leaf on the Chinese mainland contains phytoplasma, which provides a scientific basis for further identification, prevention and control of the disease.