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This study investigates the diversity and composition of soil bacterial communities in the rhizosphere of Attapadi and Nelliyampathy, prominent hill stations in Palakkad district, Kerala, India. The persistent flooding and landslides in 2018 and 2019 significantly impacted agricultural productivity in these regions. Utilizing high-throughput 16S rRNA gene sequencing (Illumina MiSeq), we conducted a comprehensive analysis of soil samples. Correlative assessments between soil parameters and microbial relative abundance at the phylum level revealed noteworthy positive associations. Notably, nitrogen (N) exhibited a positive relation with Crenarchaeota, Chloroflexi, Actinobacteriota, and Acidobacteriota; pH correlated with Firmicutes; organic carbon (OC) with WPS-2; and phosphorous with Proteobacteria. A total of 31,402 operational taxonomic units (OTUs) were identified, with the highest feature counts observed in undisturbed soils from Attapadi (AUD) and Nelliyampathy (NUD) (13,007 and 12,915, respectively). Disturbed soils in Nelliyampathy (ND) and Attapadi (AD) displayed a substantial decline in microbial diversity and composition, harbouring 1409 and 4071 OTUs, respectively. Alpha and beta diversity indices further underscored the more severe impairment of ND soils compared to AD soils. Interestingly, a majority of ND samples were landslide-affected (four out of five), while flood-affected soils accounted for four out of six AD samples. This indicates that landslides exert a more pronounced impact on microbial diversity and composition than floods. The observed decline in microbial count, composition, and diversity, even after 2 years of the disaster, raises concerns about potential threats to agricultural output. The findings emphasize the need for corrective measures, including the incorporation of microbial inoculum, to restore soil fertility in post-disaster landscapes., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Sixteen isolates of bacteria obtained from the entomopathogenic nematode (Heterorhabditis sp.) infected cadavers of Galleria mellonella larvae were identified following phenotypic characterization and molecular analysis of 16S rRNA. Two isolates were identified as the symbiotic bacterium, Photothabdus luminescens, while 14 other isolates were represented by nine species of nonsymbiotic bacteria viz., Stenotrophomonas maltophilia, Alcaligenes aquatilis, Brevundimonas diminuta, Brucella pseudointermedia, Ochrobactrum sp., Brucella pseudogrignonensis, Brucella anthropic, Pseudomonas azatoformans and Pseudomonas lactis. The phylogenetic analysis confirmed the evolutionary relationship between P. luminescens and Pseudomonas spp. The study also found a close relationship among the nonsymbiotic bacteria such as A. aquatilis, B. diminuta, Ochrobactrum sp., and Brucella spp. P. luminescens has been documented for its insecticidal effects against a wide range of insects. The two local isolates obtained in this study may be explored for their biocontrol potential against major pests of the region. Further, the association of nonsymbiotic bacteria with the EPN may be investigated., (© 2024 Wiley‐VCH GmbH.)

Background: Variety of substances such as tobacco, UV radiation, infrared rays, X-radiations, and chemicals on oral induction results in chromosomal aberrations and production of micronucleus (MN). Among them, tobacco-specific nitrosamines are potent mutagenic agents causing oral cancer., Objective: The objective of the study is to compare the genotoxicity in buccal mucosal cells, i.e. the MN count of all groups and to find the incidence of micronucleated cells (MNCs) in accordance to duration and frequency of tobacco usage and timing of contact of tobacco in the oral mucosa., Materials and Methods: Individuals without any oral diseases were divided into 3 groups having 25 in each group: smoking, chewing, and control. Smears were made from buccal exfoliated cells and stained with DNA-specific Feulgen stain. Frequency on MNC per 500 cells was assessed with one-way ANOVA and Tukey HSD multiple comparisons test and mean rank with Kruskal-Wallis test., Results: The mean micronucleus MN revealed that chewers had 8.00, smokers had 7.20 and controls had 0.4. The ANOVA test for mean frequency of micronucleated cell MNC revealed High significance (<0.001) for between groups comparison. The mean rank by Kruskal Wallis test revealed the MNC increases as the duration and frequency of habit increases. An increase in MNC in accordance to time of contact with buccal mucosa increases as the duration and time increases., Conclusion: Estimation of MN serve as an indicator of genetic damage and points that tobacco in chewing form induce genotoxic effect. This is studied in an easily accessible tissue- buccal mucosa in a non invasive manner., Competing Interests: None

Background: The formation of dental tissues is a highly delicate and complex phenomenon. Any alteration in this process leads to various dental anomalies which affect the tooth number, size, shape and structure. Supernumerary teeth are one such anomaly which affects the tooth number. Supernumerary teeth can give rise to various complications and pathologies or they may have a familial / syndromic association. They may occur along with other dental anomalies. Thus, such teeth have a definite clinical significance., Aims and Objectives: The aim of the following study was to know the prevalence of the supernumerary teeth and the distribution of the cases according to the age, sex, jaw, region, eruption status, and the position., Materials and Methods: A total of 5000 patients were examined for a period of 1 year's duration and they were divided into different groups. Group I consisted of individuals who were aged between 5-20 years, Group II consisted of individuals who were aged between 21-40 years, and Group III consisted of individuals who were aged 41 years and above. The dental examination was conducted by using a mouth mirror and a probe, to determine the presence of supernumerary teeth. All the cases with supernumerary teeth were further observed and the details were recorded in a prepared porforma. These cases were also subjected to general physical examinations (to rule out any syndromes) and radiographic examinations. Photographs were also made., Conclusion: Although supernumerary teeth is an unusual anomaly, it is not as rare as was previously reported. The identification of this anomaly could provide a hint towards the possibility of complications, pathologies, other dental anomalies, syndromes and a familial association.

A radicular cyst associated with carious teeth is a very common odontogenic lesion in the oral cavity, but calcifications in residual radicular cysts are quite rare. We report one such case where a routine pre-implant radiographic assessment revealed a mixed periapical radiopaque radiolucent lesion in the right maxillary central incisor region. Histological and radiographic studies show that there is a slow increase in the mineralized deposits within the cyst lumen with time. This becomes prominent histochemically in cysts more than 8 years old and radiographically 6 years later, as seen in our case. In this paper we would like to highlight the importance of a residual radicular cyst with calcifications in the differential diagnosis of a mixed periapical radiopaque radiolucent lesion.

Introduction: The estimation of the age of a person has been an archaic exercise, and since decades even dentists have contributed to this science with several methods through radiography. The tooth with its developmental stages provides us with a non-invasive modality to determine the age of the person., Aim: To evaluate the reliability of age estimation using Demirjian's 8 teeth method following the French maturity scores and India specific formula., Materials and Methods: The study was conducted on 121 archived digital orthopantamographs which were predominantly pre-treatment orthodontic radiographs from patients without any obvious developmental anomalies. The radiographs were divided into two gender specific groups and further sub-divided into two smaller groups of 7-16 years and 16.1-23 years. The radiographs were evaluated as per Demirjian's criteria and age was calculated using the formula developed for the Indian population., Results: The results showed that the mean absolute error for the study sample was 1.18 years; in 57.9% of cases the error rate was within ±1 year. The mean absolute error in males (7-16 years) was 1.2 years; in males (16.1-23 years) was 1.3 years; in females (7-16 years) was 0.95 years and in females (16.1-23 years) was 1.16 years., Conclusion: The age estimation using this method narrows down the error rate to just over one year making this method reliable. However the inclusion of third molar increases the error rates in the older individuals within the sample.