Pb-induced cellular defense system in the root meristematic cells of Allium sativum L

<p>Abstract</p> <p>Background</p> <p>Electron microscopy (EM) techniques enable identification of the main accumulations of lead (Pb) in cells and cellular organelles and observations of changes in cell ultrastructure. Although there is extensive literature relating to studies on the influence of heavy metals on plants, Pb tolerance strategies of plants have not yet been fully explained. <it>Allium sativum </it>L. is a potential plant for absorption and accumulation of heavy metals. In previous investigations the effects of different concentrations (10^-5to 10^-3M) of Pb were investigated in <it>A. sativum</it>, indicating a significant inhibitory effect on shoot and root growth at 10^-3to 10^-4M Pb. In the present study, we used EM and cytochemistry to investigate ultrastructural alterations, identify the synthesis and distribution of cysteine-rich proteins induced by Pb and explain the possible mechanisms of the Pb-induced cellular defense system in <it>A. sativum</it>.</p> <p>Results</p> <p>After 1 h of Pb treatment, dictyosomes were accompanied by numerous vesicles within cytoplasm. The endoplasm reticulum (ER) with swollen cisternae was arranged along the cell wall after 2 h. Some flattened cisternae were broken up into small closed vesicles and the nuclear envelope was generally more dilated after 4 h. During 24-36 h, phenomena appeared such as high vacuolization of cytoplasm and electron-dense granules in cell walls, vacuoles, cytoplasm and mitochondrial membranes. Other changes included mitochondrial swelling and loss of cristae, and vacuolization of ER and dictyosomes during 48-72 h. In the Pb-treatment groups, silver grains were observed in cell walls and in cytoplasm, suggesting the Gomori-Swift reaction can indirectly evaluate the Pb effects on plant cells.</p> <p>Conclusions</p> <p>Cell walls can immobilize some Pb ions. Cysteine-rich proteins in cell walls were confirmed by the Gomori-Swift reaction. The morphological alterations in plasma membrane, dictyosomes and ER reflect the features of detoxification and tolerance under Pb stress. Vacuoles are ultimately one of main storage sites of Pb. Root meristematic cells of <it>A. sativum </it>exposed to lower Pb have a rapid and effective defense system, but with the increased level of Pb in the cytosol, cells were seriously injured.</p

Parameterization and adaptive search for graph coloring register allocation

Graph coloring register allocators use heuristics for register coalescing and allocation, which are relevant to the number of physical registers that a group of virtual registers will use after allocation. They cannot be determined accurately in allocation, thus we made them tunable by introducing new parameters as the thresholds for coalescing and the thresholds for defining constrained live intervals in simplification. Experiments demonstrated neither the aggressive method nor the conservative method can outperform the other for all tests and the best parameters vary significantly among programs. This parameterization is profitable because the best running time reached by varying the parameters is up to 16% faster than the best of fixed-parameter methods. Hill-climbing and random probe algorithms were used to find good parameters, and the later performed better. Further analysis reveals the search space has many irregular fluctuations that are not suitable for the hill-climber

Knowledge discovery from posts in online health communities using unified medical language system

Patient-reported posts in Online Health Communities (OHCs) contain various valuable information that can help establish knowledge-based online support for online patients. However, utilizing these reports to improve online patient services in the absence of appropriate medical and healthcare expert knowledge is difficult. Thus, we propose a comprehensive knowledge discovery method that is based on the Unified Medical Language System for the analysis of narrative posts in OHCs. First, we propose a domain-knowledge support framework for OHCs to provide a basis for post analysis. Second, we develop a Knowledge-Involved Topic Modeling (KI-TM) method to extract and expand explicit knowledge within the text. We propose four metrics, namely, explicit knowledge rate, latent knowledge rate, knowledge correlation rate, and perplexity, for the evaluation of the KI-TM method. Our experimental results indicate that our proposed method outperforms existing methods in terms of providing knowledge support. Our method enhances knowledge support for online patients and can help develop intelligent OHCs in the future

Next generation sequencing in early diagnosis of pneumocystis jirovecii pneumonia after chemotherapy: a case report

The incidence of Pneumocystis pneumonia is increasing in immunosuppressive patients. How to diagnose and treat Pneumocystis pneumonia in the early stage has become an important issue for clinicians. The development of Next-generation Sequencing (NGS) provides technical support for the diagnosis of Pneumocystis pneumonia. Case report: A 14-year-old male patient was diagnosed with T lymphoblastoma and treated with chemotherapy. After chemotherapy, the patient developed bone marrow suppression and was complicated with severe pneumonia. He was given endotracheal intubation and ventilator assisted respiration. Samples of patients' alveolar lavage fluid were obtained, and Next-generation Sequencing (NGS) was used for diagnosis, confirming the pathogen as Pneumocystis jiroveci, which was treated by TMP/SMX. The patient's condition gradually improved, and was finally removed from ventilator and endotracheal tube. Pneumocystis jiroveci is a common opportunistic pathogen in immunosuppressive patients, and Next-generation Sequencing (NGS) can be used for rapid diagnosis of Pneumocystis pneumonia, thus improving the clinical therapeutic effect.

Rhabdomyolysis and acute kidney injury in the deceased donor: a case report

Rhabdomyolysis is a common complication among brain death donors, affecting the number of organ donations and the quality of donor kidneys. Case report: Male, 17 years old, admitted to the hospital due to a car accident. Subsequently, brown urine appeared, blood myoglobin increased significantly, urine output decreased, and renal function impaired. Treatments including fluid replacement, alkalization of urine, plasma exchange and bedside CRRT were given. The patient's renal function recovered, and the organs were successfully acquired. The renal function recovered well after transplantation. Conclusion: Attention should be paid to rhabdomyolysis. Early diagnosis and treatment of patients with brain death could improve donation success rate and the recovery of postoperative renal function