Balancing growth amidst salt stress - lifestyle perspectives from the extremophyte model Schrenkiella parvula.

Schrenkiella parvula, a leading extremophyte model in Brassicaceae, can grow and complete its lifecycle under multiple environmental stresses, including high salinity. Yet, the key physiological and structural traits underlying its stress-adapted lifestyle are unknown along with trade-offs when surviving salt stress at the expense of growth and reproduction. We aimed to identify the influential adaptive trait responses that lead to stress-resilient and uncompromised growth across developmental stages when treated with salt at levels known to inhibit growth in Arabidopsis and most crops. Its resilient growth was promoted by traits that synergistically allowed primary root growth in seedlings, the expansion of xylem vessels across the root-shoot continuum, and a high capacity to maintain tissue water levels by developing thicker succulent leaves while enabling photosynthesis during salt stress. A successful transition from vegetative to reproductive phase was initiated by salt-induced early flowering, resulting in viable seeds. Self-fertilization in salt-induced early flowering was dependent upon filament elongation in flowers otherwise aborted in the absence of salt during comparable plant ages. The maintenance of leaf water status promoting growth, and early flowering to ensure reproductive success in a changing environment, were among the most influential traits that contributed to the extremophytic lifestyle of S. parvula.

Transcription Factor PecS Mediates Agrobacterium fabrum Fitness and Survival.

The transcriptional regulator PecS is encoded by select bacterial pathogens. For instance, in the plant pathogen Dickeya dadantii, PecS controls a range of virulence genes, including pectinase genes and the divergently oriented gene pecM, which encodes an efflux pump through which the antioxidant indigoidine is exported. In the plant pathogen Agrobacterium fabrum (formerly named Agrobacterium tumefaciens), the pecS-pecM locus is conserved. Using a strain of A. fabrum in which pecS has been disrupted, we show here that PecS controls a range of phenotypes that are associated with bacterial fitness. PecS represses flagellar motility and chemotaxis, which are processes that are important for A. fabrum to reach plant wound sites. Biofilm formation and microaerobic survival are reduced in the pecS disruption strain, whereas the production of acyl homoserine lactone (AHL) and resistance to reactive oxygen species (ROS) are increased when pecS is disrupted. AHL production and resistance to ROS are expected to be particularly relevant in the host environment. We also show that PecS does not participate in the induction of vir genes. The inducing ligands for PecS, urate, and xanthine, may be found in the rhizosphere, and they accumulate within the plant host upon infection. Therefore, our data suggest that PecS mediates A. fabrum fitness during its transition from the rhizosphere to the host plant. IMPORTANCE PecS is a transcription factor that is conserved in several pathogenic bacteria, where it regulates virulence genes. The plant pathogen Agrobacterium fabrum is important not only for its induction of crown galls in susceptible plants but also for its role as a tool in the genetic manipulation of host plants. We show here that A. fabrum PecS controls a range of phenotypes, which would confer the bacteria an advantage while transitioning from the rhizosphere to the host plant. This includes the production of signaling molecules, which are critical for the propagation of the tumor-inducing plasmid. A more complete understanding of the infection process may inform approaches by which to treat infections as well as to facilitate the transformation of recalcitrant plant species.

Social determinants of health and glycemic control in persons with type 2 diabetes mellitus attending a tertiary hospital in Nepal: A cross-sectional study.

Background: Diabetes mellitus (DM) is an emerging global public health challenge worldwide, including Nepal. Social determinants of health (SDOH) play a major role in glycemic control among persons with type 2 DM (T2DM). However, little is known about the association between SDOH and glycemic control among individuals with T2DM in Nepal. Objective: This study aimed to identify the level of glycemic control and SDOH associated with glycemic control among Nepalese with T2DM. Methods: This cross-sectional study was conducted at a tertiary hospital in Kathmandu, Nepal, among 135 Nepalese diagnosed with T2DM who attended follow-up appointments. Convenience sampling and inclusion criteria were utilized for participant selection. Data were collected from April to June 2021 using validated scales. Descriptive statistics, Chi-square test, and binary logistic regression were employed to analyze the data. Results: The mean age of the participants in this study was 53.84 (SD = 11.78) years, and the average monthly household income was 567.64 (SD = 362.30) USD. The majority of the participants (77.8%) were literate and had no health insurance coverage (73.3%). Approximately 64.4% of the participants showed suboptimal glycemic control indicated by glycated hemoglobin (HbA1c) ≥7%. The significant determinants of good glycemic control included monthly household income of >850 USD (odds ratio [OR] = 12.20, 95% confident interval [CI] = 1.76-84.61, p = 0.011) and 341-600 USD (OR = 7.64, 95% CI 1.35-42.98, p = 0.021), being literate (OR = 6.37, 95% CI = 1.65-24.49, p = 0.007), having health insurance (OR = 5.82, 95% CI = 1.49-22.65, p = 0.011), sufficient health literacy (OR = 3.46, 95% CI = 1.10-10.83, p = 0.03), and high (OR = 16.17, 95% CI = 2.36-110.67, p = 0.005) and moderate (OR = 7.02, 95% CI = 1.26-39.07, p = 0.026) food availability, respectively. Conclusion: The study revealed suboptimal glycemic control in Nepalese with T2DM. This study presents essential social determinants of glycemic control in this population. Therefore, healthcare providers, particularly nurses, should pay more attention to assessing social determinants and provide targeted interventions to patients with T2DM who have low income, are illiterate, have no health insurance coverage, have insufficient health literacy, and have low resources for food availability.