79 research outputs found

    A Model for the Development of the Rhizobial and Arbuscular Mycorrhizal Symbioses in Legumes and Its Use to Understand the Roles of Ethylene in the Establishment of these two Symbioses

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    We propose a model depicting the development of nodulation and arbuscular mycorrhizae. Both processes are dissected into many steps, using Pisum sativum L. nodulation mutants as a guideline. For nodulation, we distinguish two main developmental programs, one epidermal and one cortical. Whereas Nod factors alone affect the cortical program, bacteria are required to trigger the epidermal events. We propose that the two programs of the rhizobial symbiosis evolved separately and that, over time, they came to function together. The distinction between these two programs does not exist for arbuscular mycorrhizae development despite events occurring in both root tissues. Mutations that affect both symbioses are restricted to the epidermal program. We propose here sites of action and potential roles for ethylene during the formation of the two symbioses with a specific hypothesis for nodule organogenesis. Assuming the epidermis does not make ethylene, the microsymbionts probably first encounter a regulatory level of ethylene at the epidermis–outermost cortical cell layer interface. Depending on the hormone concentrations there, infection will either progress or be blocked. In the former case, ethylene affects the cortex cytoskeleton, allowing reorganization that facilitates infection; in the latter case, ethylene acts on several enzymes that interfere with infection thread growth, causing it to abort. Throughout this review, the difficulty of generalizing the roles of ethylene is emphasized and numerous examples are given to demonstrate the diversity that exists in plants

    COMBINED TREATMENT OF PATIENTS WITH NON-SMALL CELL LUNG CANCER WITH PERSONALIZED PRESCRIPTION OF ADJUVANT CHEMOTHERAPY

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    Objective: To study the long-term results of the combined treatment of non-small cell lung cancer (NSCLC) using pre-surgery chemotherapy, radical surgery and personalized adjuvant chemotherapy based on the level of monoresistance genes. Methods: Four-year results of treatment of 72 patients of NSCLC II-III stage were analyzed. All patients underwent 2 courses of neoadjuvant chemotherapy (vinorelbine/carboplatin) and surgical treatment. Personalized adjuvant chemotherapy based on the levels of expression of monoresistance genes АВСС5, RRM1, TYMS, TOP1, TOP2α, TUBB3, BRCA1, and ERCC1 was performed in the main group (n=35). Three courses of adjuvant chemotherapy (vinorelbine/carboplatin) were performed in the control group (n=37). Results: In the main group the progression of the disease was observed in 14 out of 35, and in the control group – in 21 out of 37 patients. Relapsefree survival (RFS) in the main group was 60.0% (95% CI: 43.6-74.5), in the control group – 43.2% (95% CI: 28.7-59.1); Log-Rank test χ2 =3,071, р=0,080; RR=1,808 (95% CI: 0.918-3.561). The median RFS in the control group was 27 months (95% CI: 5.7-48.3). The overall survival rate in the main group was 77.1% (95% CI: 61.0-87.9), in the control group – 54.1% (95% CI: 38.4-69.0); Log-Rank test χ2 =2,813, p=0.094; RR=2,024 (95% CI: 0,870-4,709). Conclusion: The developed method of personalized prescribing adjuvant chemotherapy to patients with NSCLC based on the molecular genetic characteristics of the tumor improves relapse-free and overall survival
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