Characterization of Multiple Surface Loops in Escherichia coli Biotin Protein Ligase Functions

Multifunctional proteins utilize several strategies to interact with different partners, resulting in diverse cellular outcomes. Structural, thermodynamic and kinetic features of these proteins influence the switch between functions. The Escherichia coli biotin protein ligase, BirA, is a bifunctional protein essential for biotin homeostasis. It transfers biotin to the biotin carboxyl carrier protein (BCCP) subunit of acetyl-CoA carboxylase in its metabolic role or dimerizes and binds the biotin biosynthetic operator as a transcriptional repressor. Each function involves forming a protein-protein interaction, and because a single surface of BirA is used to form both interactions, the two are mutually exclusive. The BirA interaction surface contains several loops, two with highly conserved sequences, and the remaining with variable sequences. In this work the roles of four loops in facilitating BirA function were investigated. Amino acids from surface loops were replaced with alanine to obtain 18 alanine substituted variants. Homodimerization energetics measured using sedimentation equilibrium yielded an 8 kcal/mol range for variants from all loops. Steady-state and stopped-flow kinetic assays yielded 7 of 18 variants that exhibited slower rates than wild-type in biotin transfer to BCCP. The majority of alanine substituted variants are from constant loops. These results indicate that the biotin transfer reaction is mediated primarily through the constant loop and homodimerization is facilitated by all surface loops. The energetics of transcription repression complex assembly, which comprises contributions from dimerization and DNA binding, was assessed using DNaseI footprint titrations. Although variants exhibit a broad range in total assembly energetics, all dimers bind with similar affinities to DNA, implying independence between DNA binding and dimerization domains. The switch between functions was also investigated using inhibition DNaseI footprint titrations. A direct correlation between inhibition of repression complex assembly and rates of BirA-BCCP association was observed, reinforcing a kinetic mechanism for the switch between BirA functions. These studies indicate that multiple surface loops form the structural basis for bifunctionality, and BirA switches between protein-protein interactions through a kinetically controlled mechanism. Elucidation of structural and mechanistic aspects of the BirA functional switch enhances our understanding of how multifunctionality evolves and the mechanism of switching between biological functions

Endodontic Management of Mandibular First Molar with Middle Distal Canal: A Case Report

The knowledge of variations in root canal morphology is critical for a successful endodontic treatment. This article presents the endodontic management of a unique case of mandibular molar with middle distal canal which is quite uncommon

COMPARING THE EFFECT OF PROBIOTIC STREPTOCOCCUS SALIVARIUS K12 AND M18 ON THE STREPTOCOCCUS MUTANS COUNT, SALIVARY PH AND BUFFER CAPACITY: A RANDOMIZED DOUBLE BLINDED CLINICAL TRIAL

Aim: To evaluate and compare the effect of probiotic Streptococcus salivarius K12 and M18 on the Streptococcus mutans count, salivary pH and buffer capacity. Materials and method: 69 Subjects within the age group of 18-40 years were randomly allocated to three groups of 23 subjects each. Subjects enrolled in Group A received BLIS K12TM, Subjects in Group B received BLIS M18TM and Subjects in Group C belonged to the control group and did not receive any form of probiotics. Unstimulated salivary samples were collected at baseline and after 30 days. The samples were analysed for Streptococcus mutans level, salivary pH and buffer capacity. Results: A statistically significant reduction in salivary S. mutans levels and an increase in the salivary pH was observed after the use of probiotics when compared to the baseline. The buffer capacity remained unaltered following the use of both the probiotics. There was no change in the Streptococcus mutans level, salivary pH and buffer capacity for the subjects belonging to the control group. Conclusion: Within the limitations of the present study it can be concluded that a 30day use of Streptococcus salivarius K12 and M18 resulted in a reduction in the Streptococcus mutans count while simultaneously improving the salivary pH

Tobacco use among school children in Chennai city, India

AIMS: The present study was done to build a database on prevalence of tobacco use among students of grade 8 to 10 in Chennai city, for the purpose of advocacy of tobacco control and planning tobacco control interventions and evaluation. MATERIALS AND METHODS: A two-stage stratified probability sample of students in grades 8-10 corresponding to 13 to 15 years of age were selected from private/government aided private schools and purely government aided corporation schools. Data was collected by a pretested, closed-ended self-administered questionnaire. RESULTS: A total of 1255 students participated in this survey. Among them 64.4 boys and 35.6% were girls. Ever tobacco use was reported by 37.6% of the students (41.6 males and 30.2% females). Current users of tobacco (any products) were reported by 41.1% of the students. Prevalence was more among boy students (46.3%) when compared to that of girl students (31.6%). There existed no significant difference between current users of tobacco based on the zones of the school. Tobacco users prevalence was found more in corporation schools when compared to that of private schools. Parental and friends tobacco use was reported more often by tobacco users compared to never users. Purchasing tobacco products in a store was reported by 82.5% and almost no one was refused because of age. Almost everyone reported watching a lot of cigarette advertisements on TV, whereas about half reported watching advertisements on other medias like outdoor hoardings (45.7%), newspapers (65.3%) and social events (67.4%). CONCLUSION: This study demonstrates that among the 13 to 15-year old school going children (corresponding to grades 8 to 10) in Chennai city, the current tobacco use is high

Effect of myo-inositol and di-chiro inositol plus vitamin D supplementation during pregnancy on prevention of gestational diabetes: a multi-centric, prospective, randomized, double-blind clinical trial

Background: Aim of study was to evaluate the impact of myoinositol and D-chiro inositol plus vitamin D supplementation on the prevention of gestational diabetes mellitus (GDM) in pregnant women. Methods: In the multi-centric, prospective, randomised, double-blind clinical trial, either vitamin D alone (group I) or myoinositol and D-chiro inositol plus Vitamin D (group II) were administered to pregnant women from 12 weeks of gestation. The administration was continued until delivery to primigravids who were normoglycemic at 12 weeks of gestation and consented. From October 2018 to December 2019. A total of 1250 women were enrolled, and randomly allocated to either of the groups: 630 women in Group I and 620 in Group II. The allocation was blinded. The primary outcome was the rate of GDM as assessed by oral glucose tolerance test (OGTT) recommended by diabetes in pregnancy Study Group India (DIPSI), International Federation of Gynecology and Obstetrics (FIGO) and the Government of India, at first antenatal visit followed by at weeks 24 to 28 in both the groups. Results: The rate of GDM was found more in group I as compared to group II treated with myoinositol and D-chiro Inositol plus vitamin D, but the difference was not statistically significant (5.08% in group I and 3.22% in group II). Conclusions: In conclusion, an improved trend has been noticed in the reduction of the rate of GDM with myoinositol and D-chiro inositol plus vitamin D as compared to vitamin D alone. Myoinositol and D-chiro inositol plus vitamin D supplementation may be a good option for pregnant women to prevent the GDM occurrence especially in women having positive risk factors for GDM.

Comparison of four dental pulp-capping agents by cone-beam computed tomography and histological techniques—a split-mouth design ex vivo study

Dental pulp-capping is done to preserve vital teeth when the pulp is exposed due to caries, trauma or instrumentation. Various materials are used as pulp-capping agents. The introduction of newer materials requires scientific studies to assess their clinical efficacy. The study was designed as a split-mouth randomized analysis of four pulp-capping agents (calcium hydroxide, mineral trioxide aggregate (MTA), Biodentine and EndoSequence root repair material (ERRM)). Based on selection criteria, 15 orthodontic patients requiring the extraction of four premolars (60 teeth total) were included in the study. After pulp-capping, the teeth were extracted after 8 weeks. We analyzed the extracted teeth using cone-beam computed tomography (CBCT) and histological sections to determine the quality of the dentinal bridge and the pulpal response. Ordinal scores were given based on the completeness of the dentinal bridge, the type of bridge and the degree of pulpal inflammation. Results were analyzed using a Kruskal–Wallis test (p < 0.05) with post hoc Conover values being used when applicable. All four pulp-capping materials elicited dentinal bridge formation (60/60). MTA had the highest scores (10/15) in dentinal bridge formation followed by ERRM (8/15). Both materials showed more samples with complete dentinal bridges (9/15 each) and a favorable pulpal response (15/15). Teeth capped with calcium hydroxide showed more cases of incomplete bridge formation (9/15) and pulpal inflammation. These differences in dentinal bridge formation and pulpal inflammation were statistically significant (p 0.001 and p 0.00005, respectively), with post hoc tests revealing no significant differences between MTA and ERRM (p 0.49 and p 0.71, respectively). MTA and ERRM performed better than the other pulp-capping materials but did not differ significantly from each other. The individual preference for a pulp-capping material may be based on clinical efficacy and handling characteristics

Injectable local anaesthetic agents for dental anaesthesia

Background: Pain during dental treatment, which is a common fear of patients, can be controlled successfully by local anaesthetic. Several different local anaesthetic formulations and techniques are available to dentists. / Objectives: Our primary objectives were to compare the success of anaesthesia, the speed of onset and duration of anaesthesia, and systemic and local adverse effects amongst different local anaesthetic formulations for dental anaesthesia. We define success of anaesthesia as absence of pain during a dental procedure, or a negative response to electric pulp testing or other simulated scenario tests. We define dental anaesthesia as anaesthesia given at the time of any dental intervention. Our secondary objective was to report on patients' experience of the procedures carried out. / Search methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; the Cochrane Library; 2018, Issue 1), MEDLINE (OVID SP), Embase, CINAHL PLUS, WEB OF SCIENCE, and other resources up to 31 January 2018. Other resources included trial registries, handsearched journals, conference proceedings, bibliographies/reference lists, and unpublished research. / Selection criteria: We included randomized controlled trials (RCTs) testing different formulations of local anaesthetic used for clinical procedures or simulated scenarios. Studies could apply a parallel or cross‐over design. / Data collection and analysis: We used standard Cochrane methodological approaches for data collection and analysis. / Main results: We included 123 studies (19,223 participants) in the review. We pooled data from 68 studies (6615 participants) for meta‐analysis, yielding 23 comparisons of local anaesthetic and 57 outcomes with 14 different formulations. Only 10 outcomes from eight comparisons involved clinical testing. We assessed the included studies as having low risk of bias in most domains. Seventy‐three studies had at least one domain with unclear risk of bias. Fifteen studies had at least one domain with high risk of bias due to inadequate sequence generation, allocation concealment, masking of local anaesthetic cartridges for administrators or outcome assessors, or participant dropout or exclusion. We reported results for the eight most important comparisons. / Success of anaesthesia: When the success of anaesthesia in posterior teeth with irreversible pulpitis requiring root canal treatment is tested, 4% articaine, 1:100,000 epinephrine, may be superior to 2% lidocaine, 1:100,000 epinephrine (31% with 2% lidocaine vs 49% with 4% articaine; risk ratio (RR) 1.60, 95% confidence interval (CI) 1.10 to 2.32; 4 parallel studies; 203 participants; low‐quality evidence). When the success of anaesthesia for teeth/dental tissues requiring surgical procedures and surgical procedures/periodontal treatment, respectively, was tested, 3% prilocaine, 0.03 IU felypressin (66% with 3% prilocaine vs 76% with 2% lidocaine; RR 0.86, 95% CI 0.79 to 0.95; 2 parallel studies; 907 participants; moderate‐quality evidence), and 4% prilocaine plain (71% with 4% prilocaine vs 83% with 2% lidocaine; RR 0.86, 95% CI 0.75 to 0.99; 2 parallel studies; 228 participants; low‐quality evidence) were inferior to 2% lidocaine, 1:100,000 epinephrine. Comparative effects of 4% articaine, 1:100,000 epinephrine and 4% articaine, 1:200,000 epinephrine on success of anaesthesia for teeth/dental tissues requiring surgical procedures are uncertain (RR 0.85, 95% CI 0.71 to 1.02; 3 parallel studies; 930 participants; very low‐quality evidence). Comparative effects of 0.5% bupivacaine, 1:200,000 epinephrine and both 4% articaine, 1:200,000 epinephrine (odds ratio (OR) 0.87, 95% CI 0.27 to 2.83; 2 cross‐over studies; 37 participants; low‐quality evidence) and 2% lidocaine, 1:100,000 epinephrine (OR 0.58, 95% CI 0.07 to 5.12; 2 cross‐over studies; 31 participants; low‐quality evidence) on success of anaesthesia for teeth requiring extraction are uncertain. Comparative effects of 2% mepivacaine, 1:100,000 epinephrine and both 4% articaine, 1:100,000 epinephrine (OR 3.82, 95% CI 0.61 to 23.82; 1 parallel and 1 cross‐over study; 110 participants; low‐quality evidence) and 2% lidocaine, 1:100,000 epinephrine (RR 1.16, 95% CI 0.25 to 5.45; 2 parallel studies; 68 participants; low‐quality evidence) on success of anaesthesia for teeth requiring extraction and teeth with irreversible pulpitis requiring endodontic access and instrumentation, respectively, are uncertain. For remaining outcomes, assessing success of dental local anaesthesia via meta‐analyses was not possible. / Onset and duration of anaesthesia: For comparisons assessing onset and duration, no clinical studies met our outcome definitions. Adverse effects (continuous pain measured on 170‐mm Heft‐Parker visual analogue scale (VAS)) Differences in post‐injection pain between 4% articaine, 1:100,000 epinephrine and 2% lidocaine, 1:100,000 epinephrine are small, as measured on a VAS (mean difference (MD) 4.74 mm, 95% CI ‐1.98 to 11.46 mm; 3 cross‐over studies; 314 interventions; moderate‐quality evidence). Lidocaine probably resulted in slightly less post‐injection pain than articaine (MD 6.41 mm, 95% CI 1.01 to 11.80 mm; 3 cross‐over studies; 309 interventions; moderate‐quality evidence) on the same VAS. For remaining comparisons assessing local and systemic adverse effects, meta‐analyses were not possible. Other adverse effects were rare and minor. / Patients' experience: Patients' experience of procedures was not assessed owing to lack of data. / Authors' conclusions: For success (absence of pain), low‐quality evidence suggests that 4% articaine, 1:100,000 epinephrine was superior to 2% lidocaine, 1:100,000 epinephrine for root treating of posterior teeth with irreversible pulpitis, and 2% lidocaine, 1:100,000 epinephrine was superior to 4% prilocaine plain when surgical procedures/periodontal treatment was provided. Moderate‐quality evidence shows that 2% lidocaine, 1:100,000 epinephrine was superior to 3% prilocaine, 0.03 IU felypressin when surgical procedures were performed. Adverse events were rare. Moderate‐quality evidence shows no difference in pain on injection when 4% articaine, 1:100,000 epinephrine and 2% lidocaine, 1:100,000 epinephrine were compared, although lidocaine resulted in slightly less pain following injection. Many outcomes tested our primary objectives in simulated scenarios, although clinical alternatives may not be possible. Further studies are needed to increase the strength of the evidence. These studies should be clearly reported, have low risk of bias with adequate sample size, and provide data in a format that will allow meta‐analysis. Once assessed, results of the 34 ‘Studies awaiting classification (full text unavailable)’ may alter the conclusions of the review

Development of micronutrients and bioactive compounds rich malted drink with selected plant-based ingredients.

The study aims to develop a micronutrients and bioactive compounds rich, new malted drink formula using malted green gram (Vigna radiata), soybeans (Glycine max), watermelon (Citrullus lanatus) seed kernel and ginger (Zingiber officinale) rhizomes. The sensory analysis data revealed that the formula which contains 52.17 % of soybean flour, 26.00 % of malted green gram flour, 17.39 % of watermelon seed kernel flour and 4.34 % of ginger powder has the highest overall acceptability. This selected formula contained moisture (3.27 ± 0.29 %), total ash (3.96 ± 0.39 %), total fat (12.93 ± 0.19 %), protein (33.58 ± 0.64 %), crude fiber (2.70 ± 0.49 %), carbohydrate (43.56 ± 0.89 %), reducing sugars (4.98 ± 0.13 %) and dietary fiber (18.67 ± 0.36 %). Considerable amounts (mg/100 g) of Potassium (2332.19 ± 5.69), Phosphorus (1003.78 ± 9.12) and Magnesium (374.07 ± 3.36) were reported. The fatty acid profile was dominated by polyunsaturated fatty acids (60.53 %) including Linoleic acid (56.40 %) and α-Linolenic Acid (4.13 %). The detected amounts of prominent micronutrients and α-Linolenic Acid adequately comply with the Recommended Dietary Allowance (RDA) values. Moreover, the new formula possessed 2.3 ± 0.11 mg GAE/g of total phenolic compounds and exhibited significantly high DPPH (12.81 ± 2.19 mg/ml) and ABTS (25.16 ± 0.41 mg/ml) radical scavenging activities