Dental hard tissue erosion rates and soft drinks – A gender based analysis in Chennai city, India

AbstractBackgroundA shift in the type and quantity of beverages consumed has been noticed, especially the decrease in the intake of milk and increased consumption of soft drinks. Soft drinks have a pH level of 2 which causes the need to assess its effect on the oral cavity, especially that of dental erosion. The study was done to evaluate if dental erosion was more prevalent in any one particular gender. Also a comparison was done between carbonated and non carbonated type of soft drinks, the various amounts and frequencies of consumption, the favourite brand of soft drink and their consequent dental erosion rates were evaluated.Materials and methodsA cross sectional descriptive study was done among 400, middle income adults, belonging to the age group of 18–25years. They were examined between January and March in the year 2012, by a single examiner. A questionnaire was circulated previously in two zones of Chennai, India and the subjects were chosen by lottery method. Clinical approval was obtained from the Ethics Committee of the Department of Public Health Dentistry, SRM Dental College, India to conduct the dental assessment. The dental erosion rates were estimated using Smith and Knight Index.ResultsParticipants who consumed beverages weekly (17.65% males) had less erosion than those who consumed it daily (61.23% males). Higher the quantity of consumption more was the Erosion Index. Higher index values were seen in those who consumed only carbonated soft drinks (35.16 of female) than those who consumed only non-carbonated soft drinks (15.93% of female). On comparison of variables between genders, the p values (0.221 for type of soft drink, 0.826 for quantity of soft drink consumed) obtained were greater than the level of significance (>0.05).ConclusionsErosion causes deleterious effects to the dental hard tissues. No sex predilection was seen

Effects of green tea and chamomile tea on plaque pH, salivary pH, Streptococcus mutans count

Aim: Green tea is healthy beverage and is a part of our day to day life. Similarly, chamomile tea is known for its aspirin like properties. Beneficial effects of these tea includes protection against dental caries, periodontal disease and tooth loss and found that can a decrease in streptococcus mutans count as well as increase in pH. Hence the present study was to compare the pH of saliva and plaque, before and after the intake of green tea and to evaluate the role of green tea and chamomile tea on growth of s.mutans in culture using saliva. Material and Methods: Salivary samples were collected from 30 healthy individuals aged 20-30 years with certain criteria. The pH of saliva was determined by collecting samples before, immediately after and 15 min, 30 min after drinking tea using pH meter. Similarly the microbial colonies were also counted. The Data obtained were analyzed using Wilcoxon’s, Friedman's and Mann Whitney test. Results: There was statistically no significant difference between salivary streptococcus mutans count before and after (p 0.001) intake of green tea and chamomile tea. Conclusion: The result of the present study has proved that consumption of green tea and chamomile tea inhibit salivary Streptococcus mutans count and cause reduction of pH in saliva. So, it is advisable to encourage the regular consumption of this widely available, tasty and inexpensive beverage as an interesting alternative to other drinks

Justify your alpha

Benjamin et al. proposed changing the conventional “statistical significance” threshold (i.e.,the alpha level) from p ≤ .05 to p ≤ .005 for all novel claims with relatively low prior odds. They provided two arguments for why lowering the significance threshold would “immediately improve the reproducibility of scientific research.” First, a p-value near .05provides weak evidence for the alternative hypothesis. Second, under certain assumptions, an alpha of .05 leads to high false positive report probabilities (FPRP2 ; the probability that a significant finding is a false positive

Justify your alpha

In response to recommendations to redefine statistical significance to p ≤ .005, we propose that researchers should transparently report and justify all choices they make when designing a study, including the alpha level

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Severe hepatic fibrosis in Schistosoma mansoni infection is controlled by a major locus that is closely linked to the interferon-gamma receptor gene.

Lethal disease due to hepatic periportal fibrosis occurs in 2%-10% of subjects infected by Schistosoma mansoni in endemic regions such as Sudan. It is unknown why few infected individuals present with severe disease, and inherited factors may play a role in fibrosis development. Schistosoma mansoni infection levels have been shown to be controlled by a locus that maps to chromosome 5q31-q33. To investigate the genetic control of severe hepatic fibrosis (assessed by ultrasound examination) causing portal hypertension, a segregation analysis was performed in 65 Sudanese pedigrees from the same village. Results provide evidence for a codominant major gene, with.16 as the estimated allele A frequency predisposing to advanced periportal fibrosis. For AA males, AA females, and Aa males a 50% penetrance is reached after, respectively, 9, 14, and 19 years of residency in the area, whereas for other subjects the penetrance remains <.02 after 20 years of exposure. Linkage analysis performed in four candidate regions shows that this major locus maps to chromosome 6q22-q23 and that it is closely linked (multipoint LOD score 3.12) to the IFN-gammaR1 gene encoding the receptor of the strongly antifibrogenic cytokine interferon-gamma. These results show that infection levels and advanced hepatic fibrosis in human schistosomiasis are controlled by distinct loci; they suggest that polymorphisms within the IFN-gammaR1 gene could determine severe hepatic disease due to S. mansoni infection and that the IFN-gammaR1 gene is a strong candidate for the control of abnormal fibrosis observed in other diseases