Determination of biomarkers of chlorine exposure from biological samples: A review of analysis techniques.

Chlorine gas can be toxic when inhaled or absorbed through the skin. Exposure to high concentrations can lead to respiratory issues, eye irritation, and skin burns. It can cause pulmonary edema, pulmonary inflammation, respiratory failure, and potentially death. Accidental releases of chlorine into the environment can harm aquatic life and ecosystems. Monitoring chlorine exposure helps in implementing proper treatment and future safeguards, such as personal protective equipment and ventilation systems. Therefore, verification of chlorine exposure is crucial to protecting human health. Many biomarkers of Cl2 exposure have been proposed, and innovative methods have been used for the analysis of those markers. In this review, sample preparation methods and analytical techniques commonly used for the determination of chlorine exposure from the analysis of biological samples proposed over the last 30 years will be discussed. The most common sample preparation methods (e.g., extraction and hydrolysis) and analysis techniques (e.g., spectrometry, spectrophotometry, and chromatography) are reviewed. In addition, the major analytical challenges of chlorine analysis are discussed. The biomarkers suggested for verification of chlorine exposure and the methods used to monitor those biomarkers in chlorine-exposed individuals are critically evaluated.

Suicidal behaviours and associated factors among medical students in Bangladesh: a protocol for systematic review and meta-analysis (2000-2024).

INTRODUCTION: Suicidal behaviour is common among medical students, and the prevalence rates might vary across various regions. Even though various systematic reviews have been conducted to assess suicidal behaviours among medical students in general, no review has ever assessed or carried out a sub-analysis to show the burden of suicidal behaviours among Bangladeshi medical students. METHODS AND ANALYSIS: The research team will search the PubMed (Medline), Scopus, PsycINFO and Google Scholar databases for papers published between January 2000 and May 2024 using truncated and phrase-searched keywords and relevant subject headings. Cross-sectional studies, case series, case reports and cohort studies published in English will be included in the review. Review papers, commentaries, preprints, meeting abstracts, protocols and letters will be excluded. Two reviewers will screen the retrieved papers independently. Disagreements between two reviewers will be resolved by a third reviewer. Exposure will be different factors that initiate suicidal behaviours among medical students. The prevalence of suicidal behaviours (suicidal ideation, suicide plans and suicide attempts) in addition to the factors responsible, and types of suicide method will be extracted. Narrative synthesis and meta-analysis will be conducted and the findings will be summarised. For enhanced visualisation of the included studies, forest plots will be constructed. Heterogeneity among the studies will be assessed and sensitivity analysis will be conducted based on study quality. Included studies will be critically appraised using Joanna Briggs's Institutional critical appraisal tools developed for different study designs. ETHICS AND DISSEMINATION: The study will synthesise evidence extracted from published studies. As the review does not involve the collection of primary data, ethical approval will not be required. Findings will be disseminated orally (eg, conferences, webinars) and in writing (ie, journal paper). PROSPERO REGISTRATION NUMBER: CDR 42023493595.

Physicochemical Properties, Antioxidant Activity, and High-Performance Thin-Layer Chromatography Profiling of Propolis Samples from Western Australia.

This study reports on the physicochemical and antioxidant properties of propolis samples from various regions across Western Australia and identifies some phenolic constituents using high-performance thin-layer chromatography (HPTLC). Total phenolic content (TPC) was determined using a modified Folin-Ciocalteu assay, and antioxidant activity was investigated with the Ferric Reducing Antioxidant Power (FRAP) assay and also visualised and semi-quantified by HPTLC-DPPH analysis. TPC values ranged from 9.26 to 59.3 mg gallic acid equivalent/g of raw propolis and FRAP assay data from 4.34 to 53.8 mmol Fe2+ mmol/kg of raw propolis, although some of these variations might be related to differences in extraction yields obtained with 70% ethanol. The presence of luteolin, taxifolin, naringenin, and 4-hydroxyphenylacetic acid was confirmed based on a comprehensive, validated matching approach against an HPTLC-derived database. The findings of the study highlight the importance of future research on the chemical composition and bioactivity of Western Australian propolis.

Efficient synthesis of CRISPR-Cas13a-antimicrobial capsids against MRSA facilitated by silent mutation incorporation.

In response to the escalating global threat of antimicrobial resistance, our laboratory has established a phagemid packaging system for the generation of CRISPR-Cas13a-antimicrobial capsids targeting methicillin-resistant Staphylococcus aureus (MRSA). However, a significant challenge arose during the packaging process: the unintentional production of wild-type phages alongside the antimicrobial capsids. To address this issue, the phagemid packaging system was optimized by strategically incorporated silent mutations. This approach effectively minimized contamination risks without compromising packaging efficiency. The study identified the indispensable role of phage packaging genes, particularly terL-terS, in efficient phagemid packaging. Additionally, the elimination of homologous sequences between the phagemid and wild-type phage genome was crucial in preventing wild-type phage contamination. The optimized phagemid-LSAB(mosaic) demonstrated sequence-specific killing, efficiently eliminating MRSA strains carrying target antibiotic-resistant genes. While acknowledging the need for further exploration across bacterial species and in vivo validation, this refined phagemid packaging system offers a valuable advancement in the development of CRISPR-Cas13a-based antimicrobials, shedding light on potential solutions in the ongoing battle against bacterial infections.

Estrogenic Isoflavones in Clover Plants, Flower Nectar, Unripe Honeys and Mature Honeys: A Natural Biochemical Transformation of Isoflavones by Honeybees.

This study is the first to report on the presence of oestrogenic compounds in different clover flower nectar samples, in bee-deposited nectars collected from hive combs (unripe honey) and in mature honeys harvested from the same hives. The clover species investigated were two red clover (Trifolium pratense) cultivars, bred specifically for high isoflavone content, alongside a sainfoin (Onobrychis viciifolia) and a purple clover (T. purpureum) cultivar. A total of eight isoflavones, four of them non-glycosidic (biochanin A, formononetin, genistein and daidzein) the others glycosidic (sissotrin, ononin, genistin and daidzin), were targeted for identification and quantification in this study using high-performance thin-layer chromatography (HPTLC). Leaves and flower bracts of the clover samples were also investigated. Different isoflavone profiles were found across the four clover species and also in the different samples collected from each species indicating that, most likely due to the activity of honeybee (Apis mellifera) salivary enzymes, biochemical conversions take place when these bioactive compounds transition from flower nectar into ripe honey. Among the four investigated clover species, the two red clover cultivars, including their honeys, were found to contain higher levels of estrogenic compounds compared to other two cultivars.

Salicylic Acid Priming Improves Cotton Seedling Heat Tolerance through Photosynthetic Pigment Preservation, Enhanced Antioxidant Activity, and Osmoprotectant Levels.

The escalating global temperatures associated with climate change are detrimental to plant growth and development, leading to significant reductions in crop yields worldwide. Our research demonstrates that salicylic acid (SA), a phytohormone known for its growth-promoting properties, is crucial in enhancing heat tolerance in cotton (Gossypium hirsutum). This enhancement is achieved through modifications in various biochemical, physiological, and growth parameters. Under heat stress, cotton plants typically show significant growth disturbances, including leaf wilting, stunted growth, and reduced biomass. However, priming cotton plants with 1 mM SA significantly mitigated these adverse effects, evidenced by increases in shoot dry mass, leaf-water content, and chlorophyll concentrations in the heat-stressed plants. Heat stress also prompted an increase in hydrogen peroxide levels-a key reactive oxygen species-resulting in heightened electrolyte leakage and elevated malondialdehyde concentrations, which indicate severe impacts on cellular membrane integrity and oxidative stress. Remarkably, SA treatment significantly reduced these oxidative stresses by enhancing the activities of critical antioxidant enzymes, such as catalase, glutathione S-transferase, and ascorbate peroxidase. Additionally, the elevated levels of total soluble sugars in SA-treated plants enhanced osmotic regulation under heat stress. Overall, our findings reveal that SA-triggered protective mechanisms not only preserve photosynthetic pigments but also ameliorate oxidative stress and boost plant resilience in the face of elevated temperatures. In conclusion, the application of 1 mM SA is highly effective in enhancing heat tolerance in cotton and is recommended for field trials before being commercially used to improve crop resilience under increasing global temperatures.

The Association of Cytokines IL-2, IL-6, TNF-α, IFN-γ, and IL-10 With the Disease Severity of COVID-19: A Study From Bangladesh.

Introduction Clinically, the early prediction of the severity of COVID-19 is often challenging, as a dramatic change in severity can occur without warning. The severity of COVID-19 disease is associated with an increased level of inflammatory mediators, including cytokines. This study aimed to evaluate the association of the levels of cytokines interleukin (IL)-2, IL-6, tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), and IL-10 with the severity of COVID-19 in Bangladesh. Materials and methods This cross-sectional study included a total of 60 confirmed cases of COVID-19, comprising 30 severe cases (Group A) and 30 non-severe cases (Group B), and 10 healthy individuals (Group C) attending Bangabandhu Sheikh Mujib Medical University (BSMMU) from March 2021 to February 2022. The cytokine assay was performed using the human Th1/Th2/Th17 cytokine kit BD cytometric bead array (CBA) on the BD Accuri C6 Plus flow cytometer. Statistical analysis was conducted using IBM SPSS Statistics for Windows, Version 23 (Released 2015; IBM Corp., Armonk, New York). Results The mean ages of the patients in Groups A, B, and C were 60.73±5.97, 57.13±7.68, and 48.10±9.13 years, respectively, with a male predominance in all groups. The mean IL-2, IL-6, IL-10, and TNF-α levels had a positive correlation with the increased age group and male gender, although it was not statistically significant. The mean IL-6 and IFN-γ levels were significantly higher among severe cases (216.95±147.78 and 0.98±0.95 pg/mL, respectively) compared to non-severe cases (94.29±128.79 and 0.41±0.61 pg/mL, respectively) and healthy individuals (1.08±1.97 and 0.15±0.28 pg/mL, respectively). Furthermore, the anti-inflammatory cytokine IL-10 was also significantly higher among severe cases (17.92±21.87 pg/mL) compared to non-severe cases (5.38±6.73 pg/mL) and healthy individuals (1.62±1.65 pg/mL). Conclusion IL-6, IFN-γ, and IL-10 have a significant association with the severity of COVID-19 disease. Clinicians treating patients with COVID-19 can consider the level of these cytokines as biomarkers of severity.

Near coding-complete genome sequence of 12 dengue serotype 2 viruses from the 2023 outbreak in Bangladesh.

We report the near coding-complete genomes of 12 DENV serotype 2 strains collected during the 2023 dengue outbreak in Bangladesh. Analyses showed that all 12 strains were closely related and belonged to genotype II-Cosmopolitan.

Child-related factors associated with depressive symptoms among mothers of school-going children in urban Bangladesh: A cross-sectional study.

OBJECTIVE: This study aimed to identify the child-related factors associated with depressive symptoms among mothers of school-going children in Dhaka city of Bangladesh. METHODS: The study followed a cross-sectional design and was conducted between June and December 2019 among mothers of school-going children from Dhaka City, Bangladesh. A multistage sampling technique was adopted, and a total of 324 mothers of school-going children studying in the same school for at least six months were selected. Depressive symptoms of mothers were measured using a 20-item Self-Rating Depression Scale weighted to 100 percent, with 25-49 categorized as no depression and ≥ 50 as having depression. A binary logistic regression model was executed to identify the child-related factors associated with depressive symptoms among mothers. All statistical analyses were performed using the statistical software, Stata (Version 14.0). RESULTS: More than half of the participants (54.3%) were aged 40 years or above and had up to HSC level education (52.5%). The majority of the participants were homemakers (67.0%), mothers of a girl child (53.1%), and had a family income of 50,000 BDT or more (52.8%). Adjusted analyses revealed that the mother's depressive symptoms were associated with their child's frequent complaints of headaches or stomach aches (aOR = 13.19, 95% CI 3.03-57.37), having an injury (aOR = 4.05, 95% CI 1.44-11.41), and unfriendly relationship with mothers (aOR = 21.46, 95% CI 5.04-91.28). CONCLUSION: The present study highlighted several child-related factors that are associated with depressive symptoms among mothers that need to be considered while designing any intervention to address depressive symptoms among mothers of school-going children. It is also important to counsel mothers and fathers of the children about the importance of having a sound mother-child relationship while addressing depressive symptoms among mothers.

Emergence of SARS-CoV-2 Omicron sub-lineage JN.1 in Bangladesh.

We report complete genome sequences of 14 severe acute respiratory syndrome coronavirus 2 Omicron sub-lineage JN.1 obtained from Bangladeshi individuals between 19 December 2023 and 21 January 2024. All sequence data were generated by Oxford Nanopore Sequencing Technology using the amplicon sequencing approach developed by the ARTIC network.

Determination of Physicochemical Characteristics, Phytochemical Profile and Antioxidant Activity of Various Clover Honeys.

This paper reports on some physicochemical and phytochemical characteristics (i. e. pH, electrical conductivity, colour, moisture content, total phenolic content, sugar profile) and in vitro antioxidant activity of honeys harvested from five legume species, red clover (Trifolium pratense), balansa clover (T. michelianum), Persian clover (T. resupinatum), purple clover (T. purpureum) and sanfoin, also known as holy clover (Onobrychis viciifolia), that were grown in enclosed shade houses to ensure that the honeys' characteristics are reflective of a truly monofloral honey. Glucose and fructose, determined via High-Performance Thin-Layer Chromatography (HPTLC) analysis, were found as the main sugars in all investigated honeys with the ratio of fructose to glucose ranging from 1 : 1.2 to 1 : 1.6. The honeys' pH values ranged from 3.9 to 4.6 which met Codes Alimentarius (CA) requirements. The moisture content was found to be between 17.6 and 22.2 % which in some cases was slightly higher than CA requirements (≤20 %). The honeys' colour values, prior and after filtration, were between 825.5-1149.5 mAU and 532.4-824.8 mAU respectively, illustrating golden yellow to deep yellow hues. The total phenolic content (TPC) of the honeys was determined using a modified Folin-Ciocalteu assay. Their antioxidant activity was captured by the Ferric Reducing-Antioxidant Power (FRAP) assay as well as HPTLC analysis coupled with 2,2-diphenyl-1-picrylhydrazyl (DPPH) derivatisation. The highest total phenolic content was found in red clover honey (45.4 mg GAE/100 g) whereas purple clover honey showed the highest level of activity in the FRAP assay (7.3 mmol Fe2+/kg). HPTLC-DPPH analysis of the honeys' organic extracts demonstrated the presence of various bioactive compounds that contribute to their overall antioxidant activity. This study developed a methodology for producing monofloral clover honeys in a space limited, enclosed production system, which allowed to collate important baseline data for these honeys that can serve as the foundation for their potential future development into commercial honeys, including honeys that can be used for medicinal purposes.

Verification of chlorine exposure via LC-MS/MS analysis of base hydrolyzed chlorophenols from chlorotyrosine-protein adducts.

Inhalation of chlorine gas, with subsequent hydrolysis in the airway and lungs to form hydrochloric acid (HCl) and hypochlorous acid (HOCl), can cause pulmonary edema (i.e., fluid build-up in the lungs), pulmonary inflammation (with or without infection), respiratory failure, and death. The HOCl produced from chlorine is known to react with tyrosine to form adducts via electrophilic aromatic substitution, resulting in 3-chlorotyrosine and 3,5-dichlorotyrosine adducts. While several analysis methods are available for determining these adducts, each method has significant disadvantages. Hence, a simple and sensitive ultra-high performance liquid chromatography-tandem mass spectroscopy (UHPLC-MS/MS) method was developed for the determination of chlorotyrosine adducts. The sample preparation involves base hydrolysis of isolated plasma proteins to form 2-chlorophenol (CP) from monochlorotyrosine adducts and 2,6-dichlorophenol (2,6-DCP), from dichlorotyrosine adducts, as markers of chlorine exposure. The chlorophenols are extracted with cyclohexane prior to UHPLC-MS/MS analysis. The method produced excellent sensitivity for 2,6-DCP with a limit of detection of 2.2 µg/kg, calibration curve linearity extending from 0.054-54 mg/kg (R2 ≥ 0.9997 and %RA > 94), and accuracy and precision of 100 ± 14 %, and <15 % relative standard deviation, respectively. The sensitivity of the method for 2-CP was relatively poor, so it was used only as a secondary marker for severe chlorine exposure. The method successfully detected elevated levels of 2,6-DCP from hypochlorite-spiked plasma protein and plasma protein isolated from chlorine-exposed rats.

Immunotherapy Efficacy in Advanced Hepatocellular Carcinoma in a Diverse and Underserved Population in the United States.

Background :   Incidence of hepatocellular cancer (HCC) in the Bronx is 61% higher than the rest of New York State. Underserved populations are not well represented in clinical trials of immune checkpoint inhibitors (ICI). Methods: Demographics were tabulated for 194 patients treated with ICI at the Montefiore-Einstein Comprehensive Cancer Center (MECCC) between 2017 and 2022. Categorical variables were analyzed by Chi-squared test, and survival was analyzed using Kaplan-Meier (KM) curves. Results: MECCC patients were 40.7% Hispanic and 20.6% Black, compared with 3% and 2%, respectively, in the landmark IMbrave 150 study. Median overall survival (mOS) on ICI was 9.0 months, 25.0 months for the 100 (51.5%) favorable-prognosis Child Pugh A (CPA) patients included in HCC clinical trials. Disease control rate (DCR) was 58.5% among 123 evaluable patients per mRECIST 1.1. Baseline liver function, as defined by CP and the Model for End-Stage Liver Disease-Sodium (MELD-Na), correlated with survival (p < 0.001). Hepatitis C Virus (HCV) and alcoholism were over-represented relative to National Cancer Institute (NCI) data (56.2% vs 4.7% and 38.7% vs 8.2%, respectively). HCV treatment correlated with prolonged survival in infected patients (p = 0.0017). AFP decline correlated with response (p = 0.001). Hispanic patients lived longer when clinical variables were controlled for (mOS 52 vs 23 months; p = 0.011). Conclusion: In an underserved HCC population, ICI yielded a DCR of 58.5% and low rates of severe toxicity. This work highlights ICI efficacy in minority groups, a need for earlier HCC diagnosis and for studies of genetic and environmental factors in Hispanics with HCC.

A review of CRISPR-Cas and PCR-based methods for the detection of animal species in the food chain-current challenges and future prospects.

Regular testing and systematic investigation play a vital role to ensure product safety. Until now, the existing food authentication techniques have been based on proteins, lipids, and nucleic acid-based assays. Among various deoxyribonucleic acid (DNA)-based methods, the recently developed Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) based bio-sensing is an innovative and fast-expanding technology. The CRISPR/Cas-9 is known as Clustered Regularly Interspaced Short Palindromic Repeats due to the flexibility and simplicity of the CRISPR/Cas9 site-specific editing tool has been applied in many biological research areas such as Gene therapy, cell line development, discovering mechanisms of disease, and drug discovery. Nowadays, the CRISPR-Cas system has also been introduced into food authentication via detecting DNA barcodes of poultry and livestock both in processed and unprocessed food samples. This review documents various DNA based approaches, in an accessible format. Future CRISPR technologies are forecast while challenges are outlined.

Evaluation of the Susceptibility of Lotus Seeds (Nelumbo nucifera Gaertn.) to Aspergillus flavus Infection and Aflatoxin Contamination.

The seeds of lotus (Nelumbo nucifera Gaertn.) have been used as significant medicinal and nutritional ingredients worldwide. The abundant proteins and polysaccharides in lotus seeds make them susceptible to contamination by aflatoxin (AF), a fungal toxic metabolite. This study was conducted to investigate the susceptibility of lotus seeds at different stages of ripening to AF contamination, as well as the mechanism of the contamination. Seven groups of lotus receptacles with seeds at different ripening stages (A-G, from immature to mature) were used for the experiment. Spores of Aspergillus flavus, an AF producer, were inoculated on the water-gap area of the seeds in each receptacle. Then, each receptacle was covered with a sterilized bag, and its stalk part was soaked in water containing a life-prolonging agent, after which it was kept at room temperature for 14 days. The AF content of each whole inoculated seed from the A-G groups and that of each seed part (pericarp, cotyledon, and embryo) from the D and E groups were determined using high-performance liquid chromatography. Microtome sections were prepared from the samples and observed under a light microscope and scanning electron microscope. The seeds from the A and D groups had higher AF contents than the seeds from the B, C, E, F, and G groups, indicating that the condition of the water-gap area and the development of the embryo and cotyledon parts of the seeds are associated with AF contamination.

Role of salicylic acid in improving the yield of two mung bean genotypes under waterlogging stress through the modulation of antioxidant defense and osmoprotectant levels.

Waterlogging (WL) is a major hindrance to the growth and development of leguminous crops, including mung bean. Here, we explored the effect of salicylic acid (SA) pretreatment on growth and yield output of two elite mung bean genotypes (BU Mung bean-4 and BU Mung bean-6) subjected to WL stress. SA pretreatment significantly improved shoot dry weight, individual leaf area, and photosynthetic pigment contents in both genotypes, while those improvements were higher in BU Mung bean-6 when compared with BU Mung bean-4. We also found that SA pretreatment significantly reduced the reactive oxygen species-induced oxidative burden in both BU Mung bean-6 and BU Mung bean-4 by enhancing peroxidase, glutathione S-transferase, catalase, and ascorbate peroxidase activities, as well as total flavonoid contents. SA pretreatment further improved the accumulation of proline and free amino acids in both genotypes, indicating that SA employed these osmoprotectants to enhance osmotic balance. These results were particularly corroborated with the elevated levels of leaf water status and leaf succulence in BU Mung bean-6. SA-mediated improvement in physiological and biochemical mechanisms led to a greater yield-associated feature in BU Mung bean-6 under WL conditions. Collectively, these findings shed light on the positive roles of SA in alleviating WL stress, contributing to yield improvement in mung bean crop.

Pharmaceutical quality evaluation of marketed vildagliptin tablets in Bangladesh based on the United States Pharmacopeia specifications.

Continuous monitoring of pharmaceutical products is vital because it matters to human health. Here we aimed to assess the quality parameters of commercially available vildagliptin tablets in Bangladesh. We tested the tablets for the content uniformity, hardness, friability, disintegration, dissolution, and potency. Then, we fitted the dissolution data with kinetic models to investigate the release pattern of the studied brands. Moreover, we applied a mathematical model-independent approach to compare the dissolution profiles of the brands. The interchangeability was determined using difference and similarity factors. Weight variation, friability, and hardness were between 150.35±1.26 to 230.8±1.98 mg, 0 to 0.88%, and 47.3±5.09 to 108.1±1.92 N, respectively. All tablets disintegrated within 0.54±2.85 to 7.69±2.14 min in distilled water. The potency of tablets in 0.1 N HCl and PBS (pH 6.8) were between 97.67±2.58 to 105±0.95% and 99±4.63 to 105±1.65%, respectively. The drug release (%) in 0.1 N HCl and phosphate-buffered saline (PBS) (pH 6.8) after 60 min were between 99.37±1.80 to 111.09±0.64% and 96.59±3.52 to 109.57±0.53%, respectively. All the brands complied with the United States Pharmacopeia (USP) specification for physicochemical properties. Also, we observed the drug release patterns of vildagliptin tablets matched with different kinetic models. We found only one substitutable brand with the standard product regardless of the dissolution medium. In-vitro chemical equivalence is not always consistent with bioequivalence. Therefore, continuous evaluation of marketed products is essential to ensure the desired quality.

Prevalence and factors related to malocclusion, normative and perceived orthodontic treatment need among children and adolescents in Bangladesh

ABSTRACT Objective: The purpose of the present study was to assess the prevalence of normative and perceived orthodontic treatment need in schoolchildren and adolescents, related risk factors, and children/parent's aesthetic perception, compared to orthodontist's opinion, in Dhaka city, Bangladesh. Methods: A random sample of 800 schoolchildren aging 11-15 years was selected from different schools in the city of Dhaka, Bangladesh. The Dental Health Component (DHC) and Aesthetic Component (AC) of the Index of Orthodontic Treatment Need (IOTN) were assessed as normative treatment need. The Decayed, Missing, Filled Teeth (DMFT) index was used to record caries experience. Children were interviewed on the perception of orthodontic treatment need. Parents also completed a questionnaire on the perception of their child's orthodontic treatment need, assessed by AC/ IOTN. Results: According to the DHC/IOTN, only 24.7% were in the category of definite need (grade 4-5) for orthodontic treatment. A significant difference was found between the clinician/children and clinician/parents perceived AC score of IOTN (p= 0.0001). Multiple logistic regression showed children with a higher DMFT were significantly more likely to need orthodontic treatment, according to the DHC of IOTN. Conclusion: A low proportion of schoolchildren needs normative orthodontic treatment in the city of Dhaka, Bangladesh. Children with a higher DMFT score were significantly more likely to need orthodontic treatment, according to the DHC of IOTN.

RESUMO Objetivo: o objetivo do presente estudo foi avaliar a prevalência de necessidade real e percebida de tratamento ortodôntico em crianças e adolescentes em idade escolar, bem como de fatores de risco relacionados, e comparar a percepção estética das crianças e responsáveis com a percepção de ortodontistas na cidade de Dhaka, Bangladesh. Métodos: uma amostra aleatória composta por 800 crianças, com idades entre 11 e 15 anos, foi selecionada em diferentes escolas da cidade de Dhaka, Bangladesh. Para avaliação da necessidade real de tratamento, utilizou-se o Dental Health Component (DHC) e o Aesthetic Component (AC) do Index of Orthodontic Treatment Need (IOTN). O índice de Dentes Cariados, Perdidos e Obturados (CPO-D) foi usado para registrar a prevalência de cáries dentárias. As crianças foram entrevistadas sobre sua percepção da necessidade de tratamento ortodôntico, e os pais também responderam a um questionário sobre a percepção da necessidade de tratamento ortodôntico de seus filhos, avaliada pelo AC do IOTN. Resultados: de acordo com o DHC, apenas 24,7% das crianças foram alocadas na categoria de necessidade real (notas 4-5) de tratamento ortodôntico. As pontuações no AC foram significativamente diferentes entre os ortodontistas, as crianças e os responsáveis (p= 0,0001). A análise da regressão múltipla mostrou que as crianças com maiores pontuações no CPO-D tinham chance significativamente maior de precisar de tratamento ortodôntico, segundo o DHC. Conclusão: um número reduzido de crianças em idade escolar necessita realmente de tratamento ortodôntico em Dakha, Bangladesh. Além disso, as crianças com maior CPO-D apresentaram chance significativamente maior de precisar de tratamento ortodôntico, segundo o DHC.