Gluconacetobacter xylinus is a plant-associated bacterium best studied for its cellulose production. Bacterial cellulose is important in facilitating plant-microbe interactions but little is known about the effect that exogenous phytohormones have on bacterial cellulose synthesis or the growth of G. xylinus. We characterized the growth, development and effect on pellicle characteristics caused by exogenous indole-3-acetic acid (IAA), gibberellic acid (GA), abscisic acid (ABA) and zeatin (Z) over a range of concentrations (1 nM to 100 μM). These phytohormones are plant growth regulators known to be involved plant development including fruit ripening and stress tolerance. Each of these hormones stimulated G. xylinus growth and influenced its pellicle characteristics. Exogenous IAA had the greatest effect on G. xylinus pellicles. Growth in IAA produced thin pellicles with very little cellulose. In general, pellicle wet weight was inversely proportional to the bacterial cellulose yield when cultures were grown in the presence of ABA, suggesting ABA influenced pellicle density and hydration. The crystallinity index, CI (IR) of cellulose produced in the presence of each phytohormone over a variety of concentrations was determined by Fourier transform infrared spectroscopy. The observed effect on cellulose crystallinity was concentration and hormone dependent. GA caused the greatest alterations in crystallinity with the highest CI (IR)=0.94 at 1 μM and the lowest CI (IR)=0.47 at 500 nM. Endogenous production of hormones by G. xylinus was investigated by high performance liquid chromatography of extracts prepared from both cell pellets and culture supernatants. We found G. xylinus synthesized GA, ABA and Z but did not produce IAA.

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Background: The deficiency of vitamin b12 is highly extensive within the developed countries and is often found to remain undiagnosed within these populations. the main feature within infants suffering from vitamin b12 deficiency is altered neurological development and generalized growth. Effects of vitamin b12 deficiency on the brain can be prevented. To avoid these morbidities and mortality associated with vitamin b12 deficiency it is pivotal for clinicians to understand what other risk factors are associated with a deficiency within the infant population of developing countries. Materials and methods: This cross-sectional study was conducted on 82 healthy infants for the assessment of Vitamin B12 at Pediatric Department of LGH, Lahore from March 2021 to August 2021. Participants were selected who were healthy. After recruitment, participants underwent hematological and biochemical indices analysis. Hemoglobin, serum vitamin b12, homocysteine and methylmalonic acid were different parameters measured. Maternal vitamin b12 deficiency was investigated along with risk factor vitamin b12 deficiency in healthy infants. Results: A total of 82 recruited participants were selected after screening and meeting the recruitment criteria. After assessment of hematological data, anemia was diagnosed in 67.82% of infants (n=56). The breakdown of the anemic population showed that the male population was predominant with 58.2% affected males and 41.8% affected females. Decreased levels of plasma vitamin b12 concentration were documented in 22% of the population with a total number of 18 participants (male: 11, female: 7). Increased levels of homocysteinemia were documented in 49.1% of infants with n=40. Increased levels of methylmalonic acid were appreciated in all infants. As defined by previous criteria, the diagnosis of vitamin b12 deficiency was appreciated in 30 infants with a percentage of 38%. Furthermore, an assessment of folate deficiency showed that 8 out of 82 participants had concurrent folate deficiency in red cells with a percentile prevalence of 9.7%. maternal vitamin b12 deficiency was considered as risk factor for infant vitamin b12 deficiency Conclusion: The prevalence of vitamin b12 deficiency in healthy infants is significantly high in developing and underdeveloped countries. Vitamin b12 deficiency cooccurs with anemia and other variation of biological markers. The study concluded that among the various risk factors that may predispose an infant to vitamin b12 deficiency, maternal b12 deficiency remains the highest appreciated risk factor. Keywords: Vitamin B12, Risk Factors, Vitamin B12 deficiency, Maternal B12

Background Matrix metalloproteinase-9 (MMP-9) and antioxidants are associated with the pathogenesis of cysts and may initiate and sustain the formation of new capillaries. Objective The objective of this study was to determine the association of oxidative stress and the production of inflammatory mediators MMP-9 and interleukin 6 (IL-6) in systemic events in radicular cyst growth.