Comparative evaluation of hand and rotary file systems on dentinal microcrack formation during pulpectomy procedure in primary teeth: an in vitro study

PURPOSE

Pulpectomy can be used for the management of deep dentinal carious lesions in primary teeth which can be restored. Mechanical preparation of root canals can be performed using hand or NiTi rotary files. However, this may cause dentinal stress and consequently dentinal microcracks. Hence, the aim was comparative evaluation of hand and rotary file systems on dentinal microcrack formation during pulpectomy procedure in primary teeth.

METHODS

60 extracted primary molar teeth were selected comprising of 80 root canals. Simple random sampling was used to divide root canals into four groups (n = 20): Group A-Hedstrom file, Group B-Pro AF Baby Gold rotary, Group C-ProTaper Next rotary, and Group D-unprepared group. Assessment was conducted on presence or absence of microcracks using Chi square test (p < 0.05).

RESULTS

The total number of microcracks in Group A: one (5%), Group B: four (20%), Group C: nine (45%) and Group D: zero (0%) which was statistically significant (p = 0.002). At cervical third, the number of microcracks seen with Group A: one (5%), Group B: zero (0%), Group C: five (25%) and Group D: zero (0%) (p = 0.005). At the middle third, the number of microcracks seen in Group A: zero (0%), Group B: four (20%), Group C: four (20%) and Group D: zero (0%) (p = 0.029).

CONCLUSION

The study concluded that dentinal microcracks are formed with both hand and rotary file systems in primary teeth. ProTaper Next showed significantly higher number of microcracks, followed by ProAF Baby Gold and H files.

Surveillance of Nipah virus in Pteropus medius of Kerala state, India, 2023

Introduction

Since 2018, the Indian state of Kerala has reported four Nipah virus (NiV) disease outbreaks, raising concerns about NiV spillover from bats to the human population. Considering this, a cross-sectional study was undertaken in the Pteropus medius bat population around the Nipah virus-affected regions of Kozhikode, Kerala, India, during February, July, and September 2023.

Methods

Throat swabs, rectal swabs, and organ samples were collected from bats to test for NiV using the real-time reverse transcriptase polymerase chain reaction (RT-PCR), while serum samples were screened for anti-Nipah IgG antibodies through ELISA.

Results

An overall seroprevalence of 20.9% was observed in 272 P. medius bats tested. The throat and rectal swab samples of 321 bats were negative for NiV RNA. However, 4 of 44 P. medius bats tested positive for NiV in their liver/spleen samples. The partial N gene retrieved showed more than 99% similarity with the earlier reported NiV genome from Kerala state, India.

Discussion

The findings of the study caution that there is a spillover risk in the region and necessary precautions should be taken.

Comparative evaluation of shear bond strength of three different glass ionomer cement (conventional, zirconium-reinforced and advanced glass hybrid) in primary molars: an in vitro study

PURPOSE

The success of restorative materials is largely dependent on their capacity to adhere to the tooth structure and withstand the various forces present in the oral cavity. So, the aim of present study was to evaluate and compare the shear bond strength (SBS) of Type IX Glass Ionomer Cement (GIC), Zirconomer, and Gold Label Hybrid GIC in primary molars.

METHODS

Thirty primary molars were selected based on inclusion and exclusion criteria. The molars were polished to provide a flat dentin surface after being inserted in auto polymerizing acrylic resin. The samples were randomly divided into three groups, equally and were bonded to GIC. On the dentin surface, restoration cylinders were made using a plastic mould that had an internal diameter and height of 5 mm and 3 mm, respectively. The cement was manipulated according to the manufacturer's directions through the plastic mould. Then, the samples were stored at room temperature for 10 days to mimic oral conditions. The Universal Testing Machine was used to test SBS. One-way ANOVA and the post hoc Tukey test were used to statistically assess the collected data.

RESULTS

A statistically significant difference was found in all three groups (p < 0.01), with Zirconomer demonstrating highest SBS, followed by Type IX GIC and Gold Label Hybrid GIC.

CONCLUSION

The SBS value of Zirconomer was better when compared to Type IX GIC and Gold Label Hybrid GIC.

To Study the Clinical Profile of Thromboembolic Events in Covid 19 Patients

The sars -cov 2 causing covid 19 disease. B/l pneumonia, systemic inflammation, coagulation activation, ards , multiorgan failure are key features of covid 19. Patients need icu admission. Proinflammatory cytokines, tnf, il 6, 8, 1 beta, causes cytokine storm in covid 19 disease.

MATERIAL

In this single-center, retrospective, cross sectional study, the clinical and laboratory characteristics of 154 patients with severe covid-19 were collected. 38 Patients with severe covid -19 had incidence of thromboembolism with its symptoms, and 116 patients (ie, the controls) did not have incidence of thromboembolism. A severe case was defined as including at least one of the following criteria: (1) respiratory rate &gt;30/ min. (2) Oxygen saturation ≤90%. (3) Pao2 /fio2 ≤300mm hg. (4) Patients, either with shock or respiratory failure, requiring mechanical ventilation, or combined with other organ failure, requiring admission to intensive care unit (icu). Also pe cases were those patients with high clinical suspicion [tachycardia &gt;100 bpm, systolic arterial tension &lt;100 mmhg or signs of right ventricular pressure overload]. Pe severity was assessed using the simplified pulmonary embolism severity index (s -pesi).

OBSERVATION

Of 154 patients with severe covid-19, 38 (24.67%) Had incidence of thromboembolism. Compared with patients with severe covid-19 without incidence of thromboembolism, patients with incidence of thromboembolism were older, susceptible to receiving mechanical ventilation and admission to icu, and had higher mortality. In addition, patients with severe covid-19 with thromboembolism had higher levels of leukocyte count, neutrophil count, high-sensitivity c reaction protein, procalcitonin, ferritin, interleukin (il) 2 receptor, il-6, il-8, tumor necrosis factor α, D-dimer, fibrinogen, lactic dehydrogenase and n-terminal probrain natriuretic peptide. Among patients with severe covid-19 with incidence of thromboembolism, more non-survivors were men (30 (75%) vs women (25%)). Non-survivors had severe inflammatory response, and cardiac, hepatic, renal and coagulation impairment. Finally, the kaplan-meier survival curve showed a trend towards poorer survival in patients with severe covid-19 with incidence of thromboembolism than patients without incidence of thromboembolism. The hr was 2.24 [95% Ci 1.17-4.29], P = 0.015). After adjustment for age, sex, hypertension, cardiovascular disease and cerebrovascular disease by cox regression. The median survival durations from hospital admission in patients with severe covid-19 with and without incidence of thromboembolism were 8 days and 15 days, respectively.

CONCLUSION

The mortality rate in patients with severe covid-19 with incidence of thromboembolism is high. Incidence of thromboembolism may lead to an increase in the risk of death.

130 Expression of selected biomarker candidate genes to confer invitro maturation in Indian buffaloes

Invitro maturation (IVM) of oocytes is a crucial step and is directly related to better embryo production in buffaloes. Therefore, we planned to study gene expression of GDF9, HAS2, SPRY1, ARHGAP22, COL18A1, and GPC4 genes in IVM and immature cumulus–oocyte complexes (COCs). The COCs were recovered from follicles of slaughter origin ovaries of native buffaloes. COCs were observed under stereo zoom microscope and categorized in four grades according to morphology. Of the four grades, the first three grade COCs were considered and randomly allotted in two groups: immature treatment group (n=263) and IVM treatment group (n=272). IVM of COCs was carried out in 100-μL drops of BO-IVM medium overlaying embryo tested oil in a 35-mm petri dish under 5% CO2 in a 39.0°C incubator for 24h. Cumulus of COCs of both groups were removed by treating with 0.25% trypsin, and oocytes were stored in RNALater for future use. The expression of genes was evaluated using quantitative PCR, and the relative expression of each gene was calculated using the ΔΔCt method with efficiency correction. The logarithmic transformation of fold change (log2FC) of each candidate gene in the IVM oocyte group was computed against the immature oocyte group based on the observed cycle threshold values. Appropriate standard deviations were determined based on the observed deviations among the triplicates. The expression in the IVM treatment group of previously reported upregulated genes (GDF9, HAS2, SPRY1) was higher (up to 10-fold) compared with the immature treatment group (reference group). In the present study, relatively lower expression was observed for the other candidate genes (ARHGAP22, COL18A1, GPC4) in the bovine transcripts of oocyte, which were previously also reported as being downregulated.

Detection of coronaviruses in Pteropus & Rousettus species of bats from different States of India

Background & objectives:

Bats are considered to be the natural reservoir for many viruses, of which some are potential human pathogens. In India, an association of Pteropus medius bats with the Nipah virus was reported in the past. It is suspected that the recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) also has its association with bats. To assess the presence of CoVs in bats, we performed identification and characterization of bat CoV (BtCoV) in P. medius and Rousettus species from representative States in India, collected during 2018 and 2019.

Methods:

Representative rectal swab (RS) and throat swab specimens of Pteropus and Rousettus spp. bats were screened for CoVs using a pan-CoV reverse transcription-polymerase chain reaction (RT-PCR) targeting the RNA-dependent RNA polymerase (RdRp) gene. A single-step RT-PCR was performed on the RNA extracted from the bat specimens. Next-generation sequencing (NGS) was performed on a few representative bat specimens that were tested positive. Phylogenetic analysis was carried out on the partial sequences of RdRp gene sequences retrieved from both the bat species and complete viral genomes recovered from Rousettus spp.

Results:

Bat samples from the seven States were screened, and the RS specimens of eight Rousettus spp. and 21 Pteropus spp. were found positive for CoV RdRp gene. Among these, by Sanger sequencing, partial RdRp sequences could be retrieved from three Rousettus and eight Pteropus bat specimens. Phylogenetic analysis of the partial RdRp region demonstrated distinct subclustering of the BtCoV sequences retrieved from these Rousettus and Pteropus spp. bats. NGS led to the recovery of four sequences covering approximately 94.3 per cent of the whole genome of the BtCoVs from Rousettus bats. Three BtCoV sequences had 93.69 per cent identity to CoV BtRt-BetaCoV/GX2018. The fourth BtCoV sequence was 96.8 per cent identical to BtCoV HKU9-1.

Interpretation & conclusions:

This study was a step towards understanding the CoV circulation in Indian bats. Detection of potentially pathogenic CoVs in Indian bats stresses the need for enhanced screening for novel viruses in them. One Health approach with collaborative activities by the animal health and human health sectors in these surveillance activities shall be of use to public health. This would help in the development of diagnostic assays for novel viruses with outbreak potential and be useful in disease interventions. Proactive surveillance remains crucial for identifying the emerging novel viruses with epidemic potential and measures for risk mitigation.

An Early Passage Human Isolate of Kyasanur Forest Disease Virus Shows Acute Neuropathology in Experimentally Infected CD-1 Mice

BACKGROUND

Kyasanur Forest disease virus (KFDV) is a tick-borne Flavivirus that causes a severe illness in humans. Disease spectrum can vary from subclinical infection to fatal cases with hemorrhagic complications. The pathology of KFDV remains incompletely understood.

METHODS

This study describes the histopathologic and immunohistochemical findings in experimentally infected infant CD-1 mice with an early passage human KFDV isolate.

RESULTS

Acute histological changes were primarily seen in the brain. The spectrum of changes included gliosis, inflammatory response, necrosis, neural loss, and syncytium formation in mid and hind brain structures. Microscopic lesions observed in the liver were mainly necrosis and vacuolation of hepatocytes and in small intestine, prominent epithelial cell necrosis. KFDV antigens could be stained by a sensitive immunohistochemical labeling in the same organs.

CONCLUSIONS

Findings from this study are suggestive of neuropathology as the main manifestation of an early passaged human KFDV isolate. Importantly, this suggests that KFDV may be causing primarily a neurologic disease and secondary organ damage could be because of disease pathology per se. The use of primary low passage human isolates and neuropathology profile could also be more apt in developing a challenge model for testing potential antivirals and therapeutic agents.

A preliminary study of recombinant human interferon-α-2a activity against rabies virus in murine model

Rabies remains an important public health problem in the world due to uncontrolled enzootic rabies. Although rabies associated fatalities may be prevented with timely immunoprophylaxis, but till date a therapeutic molecule has remained elusive. We investigated the role of rhuIFN α-2a in murine model challenged with rabies virus. Titre of 10(4.25) LD50/0.03 ml of 10% w/v RV CVS stock suspension were obtained. Based on 1LD50 titre, challenge dose of 50 LD 50 was administered along with rhuIFN α-2a with pre-exposure (primed) and post-exposure with the rabies virus. Both showed increased survival time as compared with the virus controls. These findings suggest that the rhuIFN α-2a might have some anti-viral activity, which can be used for the treatment of rabies infection. Further research on the efficacy of interferon along with anti-viral drugs for the treatment will be helpful in designing combination therapy against the disease.