Volatile profiling as a potential biochemical marker for validation of gamma irradiation derived putative mutants in polyembryonic genotypes of mango (Mangifera indica L.).

Introduction: Putative mutants were generated through gamma irradiation in the polyembryonic mango genotype Nekkare. The putative mutant progenies along with control seedlings and mother plants were evaluated by comparing the compositions and relative proportions of their major volatile compounds. Methods: Volatile profiling was done using headspace-solid phase micro-extraction (HS SPME) method coupled with gas chromatography-mass spectrometry (GC-MS MS). Furthermore, characterisation of putative mutants and control seedlings was carried out using simple sequence repeat (SSR) markers to ascertain the genetic diversity present in the samples under study. Results: Monoterpenes were the most abundant volatile compound in all the studied samples (ranging from 34.76% to 91.41%) out of which I-Phellandrene and cis-Ocimene formed the major fraction in mother plants (20.45%-21.86% and 16.17%-21.27%, respectively) and control seedlings (23.32%-24.95% and 18.95%-20.81%, respectively), while beta-Phellandrene was dominant in the selected putative mutant samples (2.34%-29.53%). Among sesquiterpenes, trans-Caryophyllene was detected only in the putative mutant samples (0.10%-30.18%). Grouping together of mother plants and control seedlings was seen in the cluster analysis, while the putative mutants grouped apart from them suggesting genetic diversity. Genetic distance between the mother plants and control seedlings ranged from 0.97 to 2.73, while between putative mutants, control seedlings, and mother plants, it ranged from 6.54 to 9.82. SSR-based characterisation of putative mutant seedlings showed that mutation caused variability in the treated population. This was evident from the high allelic richness ranging from 4 to 12 with a mean of 7 and a higher mean Shannon's Information Index (1.50) of the putative mutant population. Discussion: The study demonstrates that volatile profiling and molecular characterisation using SSR markers could be used as a tool to detect variation in a mutated population. In addition, volatile profiling can be used to validate putative mutants in polyembryonic mango genotypes where the seedlings of nucellar origin are similar to mother plants.

Comparative transcriptome analysis provides novel insights into molecular response of salt-tolerant and sensitive polyembryonic mango genotypes to salinity stress at seedling stage.

Introduction: Increased soil salinity in the recent years has adversely affected the productivity of mango globally. Extending the cultivation of mango in salt affected regions warrants the use of salinity tolerant/resistant rootstocks. However, the lack of sufficient genomic and transcriptomic information impedes comprehensive research at the molecular level. Method: We employed RNA sequencing-based transcriptome analysis to gain insight into molecular response to salt stress by using two polyembryonic mango genotypes with contrasting response to salt stress viz., salt tolerant Turpentine and salt susceptible Mylepelian. Results: RNA sequencing by Novaseq6000 resulted in a total of 2795088, 17535948, 7813704 and 5544894 clean reads in Mylepelian treated (MT), Mylepelian control (MC), Turpentine treated (TT) and Turpentine control (TC) respectively. In total, 7169 unigenes annotated against all the five public databases, including NR, NT, PFAM, KOG, Swissport, KEGG and GO. Further, maximum number of differentially expressed genes were found between MT and MC (2106) followed by MT vs TT (1158) and TT and TC (587). The differentially expressed genes under different treatment levels included transcription factors (bZIP, NAC, bHLH), genes involved in Calcium-dependent protein kinases (CDPKs), ABA biosynthesis, Photosynthesis etc. Expression of few of these genes was experimentally validated through quantitative real-time PCR (qRT-PCR) and contrasting expression pattern of Auxin Response Factor 2 (ARF2), Late Embryogenesis Abundant (LEA) and CDPK genes were observed between Turpentine and Mylepelian. Discussion: The results of this study will be useful in understanding the molecular mechanism underlying salt tolerance in mango which can serve as valuable baseline information to generate new targets in mango breeding for salt tolerance.

A correlative study of sella turcica bridging and dental anomalies related to size, shape, structure, number and eruption of teeth.

OBJECTIVE: The main objective of this study is to get a wider and clearer idea about the relationship between sella turcica bridging and the type of dental anomalies related to size, shape, number, structure and eruption of teeth. MATERIALS AND METHODS: For the present study, 50 pretreatment lateral cephalometric radiographs showing complete sella turcica bridging were retrieved from the 500 existing case records of patients. The control group consisted of 50 pretreatment lateral cephalograms without sella turcica bridging retrieved from the same case records by using simple random sampling. After collection of the samples, retrospective study was performed with the analysis of patient records to assess any associated dental anomaly in patients with sella turcica bridging and patients without sella turcica bridging. Shafer's classification of morphological variations in size, shape, structure, number and eruption of teeth was used to analyze and group the dental anomalies. RESULTS: The incidence of dental anomalies related to number and size of teeth was found to be higher in cases with sella turcica bridging. CONCLUSION: Lateral cephalogram is used by orthodontist routinely for diagnosis and treatment planning; it can be used as a prediction tool for dental anomalies as well. Early detection of skeletal anomalies can be used to forecast the presence of dental anomalies later in life, which will help the clinician to adopt preventive measures.

Association of Wnt9B rs1530364 and Wnt5A rs566926 Gene Polymorphisms with Nonsyndromic Cleft lip and Palate in South Indian Population using Deoxyribonucleic Acid Sequencing.

CONTEXT: Nonsyndromic cleft lip with or without cleft palate (CL/CP) is a common congenital facial malformation without any other structural or developmental abnormalities. AIMS AND OBJECTIVES: To test the association of Wnt9B rs1530364 and Wnt5A rs566926 gene variants with the nonsyndromic CL/CP patients in South Indian population. METHODS: Deoxyribonucleic acid (DNA) samples of 25 subjects with nonsyndromic cleft lip and palate (NSCLP) and 25 unrelated controls collected from the department were used for the study. Group A: DNA samples of 25 subjects NSCLP (P1-P25). Group B: DNA samples of 25 unrelated controls (C1-C25). The extracted DNA samples were subjected to polymerase chain reaction, and later, these amplified products were subjected to DNA sequencing. Results were documented in the form of electropherograms. RESULTS: The results indicated that there is a strong association between the presence of Wnt9B rs1530364 gene with the incidence of NSCLP. This study also suggests that the likelihood of NSCLP is higher in subjects having CC (P = 0.02) genotype for Wnt9B gene variant rs1530364. CONCLUSION: We can conclude that Wnt9B gene variant rs1530364 can be considered as genetic marker for NSCLP for our population.

In vitro evaluation of microbial contamination and the disinfecting efficacy of chlorhexidine on orthodontic brackets.

BACKGROUND: Contamination of orthodontic appliances is due to the unhygienic practices followed during manufacturing and packaging processes, which may lead to cross-contamination. Although literature has indicated the need for sterilization or disinfection of orthodontic appliances before using in the oral cavity, this is still not employed in routine clinical practice. In this view, the current study evaluates the bacterial load on orthodontic brackets along with the disinfecting efficacy of chlorhexidine. METHODS: A total of 140 brackets were obtained from four different manufacturers and divided into six groups: group 1 (American Orthodontics; n = 30), group 2 (3M Unitek; n = 30), group 3 (Ortho Organizers; n = 30), group 4 (China Dental Orthodontic; n = 30), group 5 (negative control; n = 10), and group 6 (positive control; n = 10). Various microbiological and biochemical tests were conducted on the brackets to detect the type and growth of bacteria. Brackets that showed microbial contamination were then subjected to disinfection using 0.01% and 2% chlorhexidine solutions. RESULTS: Microbial contamination was detected on brackets of all the four groups. Bacteria, including Staphylococcus aureus, S. epidermidis, Lactobacilli, Klebsiella pneumoniae, Bacillus licheniformis, and B. cereus, were identified in these groups. Upon disinfection with 0.01% chlorhexidine solution, brackets in group 2 displayed complete decontamination, while all brackets in the other groups containing gram-negative bacteria exhibited complete decontamination with 2% chlorhexidine. CONCLUSION: Orthodontic brackets received from four manufacturers showed high bacterial contamination. Disinfecting ability of 2% chlorhexidine proved highly effective in destroying both gram-positive and gram-negative bacteria. Therefore, use of 2% chlorhexidine in clinical practice for the disinfection of orthodontic brackets is suggested, before placement in the oral cavity.

A Study on the Expression of Genes Involved in Carotenoids and Anthocyanins During Ripening in Fruit Peel of Green, Yellow, and Red Colored Mango Cultivars.

Mango (Mangiferaindica L.) fruits are generally classified based on peel color into green, yellow, and red types. Mango peel turns from green to yellow or red or retain green colors during ripening. The carotenoids and anthocyanins are the important pigments responsible for the colors of fruits. In the present study, peels of different colored cultivars at three ripening stages were characterized for pigments, colors, and gene expression analysis. The yellow colored cultivar "Arka Anmol" showed higher carotenoid content, wherein ß-carotene followed by violaxanthin were the major carotenoid compounds that increased during ripening. The red colored cultivars were characterized with higher anthocyanins with cyanidin-3-O-monoglucosides and peonidin-3-O-glucosides as the major anthocyanins. The gene expression analysis by qRT-PCR showed the higher expression of carotenoid biosynthetic genes viz. lycopene-ß-cyclase and violaxanthin-de-epoxidase in yellow colored cv. Arka Anmol, and the expression was found to increase during ripening. However, in red colored cv. "Janardhan Pasand," there is increased regulation of all anthocyanin biosynthetic genes including transcription factors MYB and basic helix loop. This indicated the regulation of the anthocyanins by these genes in red mango peel. The results showed that the accumulation pattern of particular pigments and higher expression of specific biosynthetic genes in mango peel impart different colors.

MiSNPDb: a web-based genomic resources of tropical ecology fruit mango (Mangifera indica L.) for phylogeography and varietal differentiation.

Mango is one of the most important fruits of tropical ecological region of the world, well known for its nutritive value, aroma and taste. Its world production is >45MT worth >200 billion US dollars. Genomic resources are required for improvement in productivity and management of mango germplasm. There is no web-based genomic resources available for mango. Hence rapid and cost-effective high throughput putative marker discovery is required to develop such resources. RAD-based marker discovery can cater this urgent need till whole genome sequence of mango becomes available. Using a panel of 84 mango varieties, a total of 28.6 Gb data was generated by ddRAD-Seq approach on Illumina HiSeq 2000 platform. A total of 1.25 million SNPs were discovered. Phylogenetic tree using 749 common SNPs across these varieties revealed three major lineages which was compared with geographical locations. A web genomic resources MiSNPDb, available at http://webtom.cabgrid.res.in/mangosnps/ is based on 3-tier architecture, developed using PHP, MySQL and Javascript. This web genomic resources can be of immense use in the development of high density linkage map, QTL discovery, varietal differentiation, traceability, genome finishing and SNP chip development for future GWAS in genomic selection program. We report here world's first web-based genomic resources for genetic improvement and germplasm management of mango.

Construction of a three-dimensional finite element model of maxillary first molar and it's supporting structures.

The finite element method (FEM) is a powerful computational tool for solving stress-strain problems; its ability to handle material inhomogeneity and complex shapes makes the FEM, the most suitable method for the analysis of internal stress levels in the tooth, periodontium, and alveolar bone. This article intends to explain the steps involved in the generation of a three-dimensional finite element model of tooth, periodontal ligament (PDL) and alveolar bone, as the procedure of modeling is most important because the result is based on the nature of the modeling systems. Finite element analysis offers a means of determining strain-stress levels in the tooth, ligament, and bone structures for a broad range of orthodontic loading scenarios without producing tissue damage.

Integration of the Herbst and Begg appliance in the management of severe Class II malocclusion.

The efficacy of the Herbst appliance in a normalizing sagittal relationship in patients with a Class II malocclusion is well-documented. This case report describes the treatment of a 14-year-old male patient with severe Class II Division 1 malocclusion due to retrognathic mandible and mildly prognathic maxilla, convex profile, and lip trap. He had severely proclined maxillary incisors and retroclined mandibular incisors, overjet of 13 mm and overbite of 7 mm. Since the patient was in the peak pubertal growth phase, growth modulation was carried out with the Herbst appliance for 8 months, followed by fixed appliance therapy with the Begg appliance for 11 months. Combination of Herbst and Begg appliance led to a very favorable treatment outcome and greatly improved the patient's appearance.

Association of Transforming Growth Factor Alpha and Methylenetetrahydrofolate reductase gene variants with nonsyndromic cleft lip and palate in the Indian population.

OBJECTIVES: The aim was to evaluate the relationship of the K-primer variant of the transforming growth factor-alpha (TGF-α) gene and C677T variant of the methylenetetrahydrofolate reductase (MTHFR) gene with nonsyndromic cleft lip and palate (CL/P) in the Indian population. SETTING AND SAMPLE POPULATION: The study group consisted of DNA samples of 25 subjects with nonsyndromic CL with or without cleft palate and 25 unrelated controls, already existing in the Department of Orthodontics, D.A.P.M.R.V. Dental College, Bengaluru, Karnataka, India. MATERIALS AND METHODS: THE DNA SAMPLES WERE DIVIDED INTO TWO CATEGORIES: Group A which included the 25 subjects with nonsyndromic CL/P; and Group B, which consisted of the 25 unrelated controls. The polymerase chain reaction (PCR) test was done for amplification of the region of interest from the DNA samples. Restriction digestion was then performed on the amplified product using the restriction enzyme HinfI, separately for each of the variants. The digested PCR products were separated into channels on a 1.5% agarose gel containing ethidium bromide in an electrophoretic chamber. A U.V. transilluminator was used to see the specific bands of base pairs of the digested PCR products. RESULTS: In Group A, the TGF-α gene variant was present in 16 subjects (P = 0.001) and MTHFR gene variant was present in 8 subjects (P = 0.185). A combination of both gene variants were present in seven subjects, which was an interesting finding. In Group B, four subjects tested positive for the TGF-α and MTHFR gene variants. CONCLUSIONS: The TGF-α gene variant and a combination of TGF-α + MTHFR gene variants significantly contribute to the development of nonsyndromic CL/P and can be considered as genetic markers for Indian population. The MTHFR gene variant, though a minor risk factor, cannot be considered as a genetic marker.

Van der Woude syndrome: Management in the mixed dentition.

This article presents the case of a patient with Van der Woude syndrome treated with orthodontic and orthopedic intervention in the mixed dentition stage. The patient had a bilateral cleft of the lip and alveolus accompanied by lip pits on the lower lip. Intra-orally, there was bilateral anterior and posterior cross-bite with a collapsed maxilla. The maxillary transverse deficiency was managed with orthopedic expansion and the second phase of treatment involved secondary alveolar bone grafting followed by retention with functional regulator-3. The mild maxillary retrognathia and deficient lip support was managed with dental compensation.

Comparison of reproducibility of natural head position using two methods.

UNLABELLED: Lateral cephalometric radiographs have become virtually indispensable to orthodontists in the treatment of patients. They are important in orthodontic growth analysis, diagnosis, treatment planning, monitoring of therapy and evaluation of final treatment outcome. AIM: The purpose of this study was to evaluate and compare the maximum reproducibility with minimum variation of natural head position using two methods, i.e. the mirror method and the fluid level device method. MATERIALS AND METHODS: The study included two sets of 40 lateral cephalograms taken using two methods of obtaining natural head position: (1) The mirror method and (2) fluid level device method, with a time interval of 2 months. Inclusion criteria • Subjects were randomly selected aged between 18 to 26 years Exclusion criteria • History of orthodontic treatment • Any history of respiratory tract problem or chronic mouth breathing • Any congenital deformity • History of traumatically-induced deformity • History of myofacial pain syndrome • Any previous history of head and neck surgery. RESULTS: The result showed that both the methods for obtaining natural head position-the mirror method and fluid level device method were comparable, but maximum reproducibility was more with the fluid level device as shown by the Dahlberg's coefficient and Bland-Altman plot. The minimum variance was seen with the fluid level device method as shown by Precision and Pearson correlation. CONCLUSION: The mirror method and the fluid level device method used for obtaining natural head position were comparable without any significance, and the fluid level device method was more reproducible and showed less variance when compared to mirror method for obtaining natural head position. CLINICAL SIGNIFICANCE: Fluid level device method was more reproducible and shows less variance when compared to mirror method for obtaining natural head position.

Applicability of two methods of mixed dentition analysis in a contemporary Indian population sample.

AIM: More than 10 years experience in implementing the Tanaka Johnston and Moyers methods has shown that they overestimate the sizes of unerupted canines and premolars when used in populations other than the Caucasian. This study was designed to assess the applicability of the two most commonly used methods of mixed dentition analysis and to attempt to derive a more accurate and precise formula to predict the sizes of the unerupted premolars and canines in a sample of Indian population. MATERIALS AND METHODS: The sample included 200 study models (100 male, 100 female). Tanaka Johnston's and Moyer's equations were applied to this sample and the mean differences between the actual and estimated tooth widths were determined. New regression equations were derived using lower first molars and incisors as the predictors. RESULTS: The mean difference between the actual and estimated values of canines and premolars using Tanaka Johnston's and Moyers methods were clinically and statistically significant. Therefore new regression equations were derived taking lower first molars and incisors as the predictors for both sexes. On validation, these equations were found to be accurate and precise for this population. CONCLUSION: It is recommended to use these equations as a method of mixed dentition analysis for the Indian population.