Impairment of sperm efficiency in mice following short-term nano-titanium dioxide exposure: An experimental study

Background: Titanium dioxide nanoparticles (TiO2NPs) are widely used in many compounds. Recent evidence has displayed some cytotoxic effects of TiO2NPs on male reproduction. Objective: The effects of TiO2NP administration on sperm parameters and chromatin and seminiferous histopathology of male mice were investigated. Materials and Methods: In this experimental study, 32 NMRI male mice (35 ± 3 gr, 8-12-week-old) were divided into four groups (n = 8/each): treated groups were fed orally with 2.5 (group I), 5 (group II) and 10 (group III) mg/kg/day TiO2NPs for 40 days and the control group received phosphate buffered saline. Sperm parameters, DNA integrity and chromatin quality were assessed using chromomycin A3, aniline blue, toluidine blue staining and TUNEL. Hematoxylin eosin staining was performed to measure spermatogenic cells and the total diameter of seminiferous tubules. Also, sex hormone and malondyaldehyde levels were measured. Results: Abnormal sperm tails rose in group III (28.87 ± 4.91) in comparison with the control group (12.75 ± 3.95). However, chromomycin A3 staining and TUNEL showed higher levels in group III in comparison with the control group, whereas aniline blue and toluidine blue staining showed no differences. A significantly lower spermatogenesis index and lumen parameters were observed in group III. Leydig cell numbers, cellular diameters and the area of the seminiferous tubules were lower in the treated groups. The testosterone level was also lower in these groups and the percentage of malondyaldehyde in the seminal fluid was higher. Conclusion: Exact mechanisms of TiO2NPs are not clear; however, cytotoxic and genotoxic effects of TiO2NPs may relate to oxidative stress. Given their widespread use, TiO2NPs should be a public health focus of attention. Key words: Titanium dioxide, Spermatogenesis, Histology, Mouse, Chromatin, TUNEL.

Binding of toluidine blue-myristic acid derivative to cucurbit[7]uril and human serum albumin: computational and biophysical insights towards a biosupramolecular assembly

A new toluidine blue-myristic acid photosensitizer derivate (TBOMyr) was investigated as a design molecule to bind simultaneously to cucurbit[7]uril (CB[7]) and human serum albumin (HSA) with the aim of constructing...

Poly Lactic-co-Glycolic Acid-Coated Toluidine Blue Nanoparticles for the Antibacterial Therapy of Wounds

Bacterial infections in wounded skin are associated with high mortality. The emergence of drug-resistant bacteria in wounded skin has been a challenge. Toluidine blue (TB) is a safe and inexpensive photosensitizer that can be activated and used in near-infrared photodynamic therapy to effectively kill methicillin-resistant Staphylococcus aureus (MRSA). However, its aggregation-induced quenching effect largely affects its clinical applications. In this study, TB nanoparticles (NPs) were synthesized using an ultrasound-assisted coating method. Their physicochemical and biological properties were studied and evaluated by scanning electron microscopy and Fourier-transform infrared spectroscopy. The TBNPs had a broad-spectrum antibacterial activity against Gram-positive bacteria (MRSA) and Gram-negative bacteria (E. coli). In addition, MTT, hemolysis, and acute toxicity tests confirmed that TBNPs had good biocompatibility. The TBNPs exhibited a high photodynamic performance under laser irradiation and efficiently killed E. coli and MRSA through generated reactive oxygen species, which destroyed the cell wall structure. The potential application of TBNPs in vivo was studied using an MRSA-infected wound model. The TBNPs could promote wound healing within 7 days, mainly by reducing the inflammation and promoting collagen deposition and granulation tissue formation. In conclusion, the TBNPs offer a promising strategy for clinical applications against multiple-drug resistance.

Diagnostic accuracy of toluidine blue in early detection of oral squamous cell carcinoma

Background: Indian sub-continent (India, Pakistan, and Bangladesh) is one of the high-risk populations for oral cancer cases. Intraoral screening is critical to diagnosis and treating oral cancer at an early stage for a better prognosis. Among the diagnostic adjuncts, toluidine blue staining is considered a simplistic, cost-effective, and highly sensitive method. The objective of the current study was to find out the diagnostic accuracy of toluidine blue in the early detection of oral squamous cell carcinoma. Patients and methods: This prospective observational study was undertaken at the Department of Oral and Maxillofacial Surgery, Institute of Dentistry, CMH Lahore Medical College from15-09-2019 to 15-03-2020 after getting approval from IRB. Based on inclusion criteria, a sample size of 100 was calculated and enrolled in the study. Non-probability convenient sampling technique was utilized. Oral staining of 100 patients was done with 1% toluidine blue on an OPD basis, and incisional biopsies were then performed. Staining pattern and histopathology reports of patients were evaluated to assess the diagnostic accuracy Results: The study results revealed the sensitivity of Toluidine Blue as 89.87%, and specificity of toluidine blue was found as 76.19%. Positive and negative predictive values of Toluidine Blue remained 93.42% and 66.67%, respectively. Conclusion: Toluidine blue has good diagnostic accuracy for early detection of oral squamous cell carcinoma (SCC).

Adjunctive Utility of Toluidine Blue in Detecting Dysplastic Cells in Oral Mucosal Lesions in Comparison with Histopathology

Introduction: Oral cancer is one of the most common cancers globally and in Sri Lanka, which follows premalignant lesions. It is curable if it is detected early. Several adjunctive methods to diagnose premalignant lesions early are available. Among these, Toluidine blue staining method before a biopsy is currently receiving much attention. Method: This is a prospective study done by studying 103 patients presented to the Oral and Maxillofacial Surgery Unit, District General Hospital, Gampaha, Sri Lanka. The oral lesions of all the patients are categorized as benign, premalignant, and malignant by clinical examination. Toluidine Blue mouth wash is introduced to all the patients, followed by biopsy from the stained sites and the clinically decided sites in non-stained lesions. Histopathological diagnosis was obtained for all cases. The accuracy of diagnosis of premalignant, malignant, and benign cases by clinical assessment and by using Toluidine blue was assessed and compared statistically in relation to sensitivity, specificity, positive predictive and negative predictive values, and likelihood ratios (LR). Results: Toluidine blue has no added advantage over clinical examination in our setup even though it might be helpful in screening. However, it has an added value to confirm clinically benign cases as benign. Conclusion: Toluidine Blue can be used as an adjunct in screening and to confirm clinically benign cases so that those can be followed up in clinics without doing unnecessary biopsies.

A nano phototheranostic approach of toluidine blue conjugated gold silver core shells mediated photodynamic therapy to treat diabetic foot ulcer

Diabetic foot infection caused by multidrug-resistant bacteria, is becoming serious problem. Moreover, polymicrobial biofilms contribute significantly to the persistent infections. In the present study, we investigated the effectiveness of novel toluidine blue conjugated chitosan coated gold–silver core–shell nanoparticles (TBO–chit–Au–AgNPs) mediated photodynamic therapy and demonstrate their use as a nontoxic antibacterial therapy to combat diabetic foot ulcer (DFU) caused by multi-drug resistant strains both in monomicrobial and polymicrobial state of infection. In vitro efficacy of TBO–chit–Au–AgNPs mediated photodynamic therapy (PDT) against polymicrobial biofilms was determined using standard plate count method and compared with that of monomicrobial biofilms of each species. Different anti-biofilm assays and microscopic studies were performed to check the efficacy of TBO–chit–Au–AgNPs mediated PDT, displayed significant decrease in the formation of biofilm. Finally, its therapeutic potential was validated in vivo type-2DFU. Cytokines level was found reduced, using nano-phototheranostic approach, indicating infection control. Expression profile of growth factors confirmed both the pathogenesis and healing of DFU. Hence, we conclude that TBO–chit–Au–AgNPs mediated PDT is a promising anti-bacterial therapeutic approach which leads to a synergistic healing of DFU caused by MDR bacterial strains.

A COMPARATIVE STUDY OF HEMATOXYLIN & EOSIN, SPECIAL STAINS AND IMMUNOHISTOCHEMISTRY FOR DETECTION OF HELICOBACTER PYLORI IN CASES OF GASTRITIS

Background: The role of Helicobacter Pylori in the pathogenesis of Gastritis-Peptic ulcer syndrome and its association with the development of upper gastrointestinal tract malignancy warrant efcient method for the identication of the bacteria in biopsy specimens. Four methods - Hematoxylin and Eosin, Giemsa, Toluidine Blue and Immunohistochemistry were compared to detect the presence of Helicobacter pylori. The prevalence of H.Pylori in gastric biopsies was also evaluated. Aim Of The Study: The aim is to evaluate the prevalence of H.Pylori in cases of gastritis and compare the efcacy of Hematoxylin and Eosin, Giemsa , Toluidine blue and Immunohistochemistry for the detection of H.pylori in cases of gastritis. Materials And Methods: This Retrospective study was done in the Department of Pathology. A total of 40 cases of gastritis were randomly selected for this study and all the four methods were applied. Results: Helicobacter pylori infection showed an overall prevalence rate of about 75%. When compared with Immunohistochemistry, Sensitivity and specicity of Hematoxylin and Eosin was 66.67% and 100% respectively. Giemsa showed sensitivity of about 86.67% and specicity of about 100%. Toluidine blue showed sensitivity of about 80% and specicity of about 100%. Conclusion: Hence in the present study Giemsa was more reliable and cost effective stain when compared with Hematoxylin & Eosin, Toluidine blue and immunohistochemistry. However, Immunohistochemistry carries the highest level of sensitivity in the detection of Helicobacter Pylori especially when the density of organism is low and in clinically suspected cases of Helicobacter Pylori with negative Giemsa staining

Photodynamic Therapy Using Toluidine Blue O (TBO) Dye as a Photosensitizer against Leishmania major

Background: Photodynamic therapy (PDT) is alternative treatment of cutaneous leishmaniasis (CL), and phenolthiazine dyes such as Toluidine Blue O (TBO) have the potential role in PDT and notably affect parasites inactivation. This study aimed to evaluate the effectiveness of PDT by using TBO and a light-emitting diode (LED) in the treatment of zoonotic CL (ZCL). Methods: The study was conducted in Iran University of Medical Sciences, Tehran, Iran in 2018-2020. Different concentration (7.8 µg/ mL up to 500 µg/ mL) of TBO as a photosensitizer and a 630 nm LED light as a source of light were used for antileishmanial activity against both forms of Leishmania major promastigotes and intracellular amastigotes. Effective concentration (EC50) and cell cytotoxicity (CC50) were calculated in both infected and non-infected J774.A1 macrophages, respectively. As well as inhibitory concentration (IC50) was quantified in L. major promastigotes for 2 h, 24 h, and 48 h after incubation using a MTT colorimetric assay. Results: TBO dye in combination with the PDT significantly decreases the L. major promastigotes and intracellular amastigotes viability when compared with TBO alone. Both TBO dye in combination with the PDT and TBO alone had no toxic effects on the mice macrophages; however, it significantly killed the entered parasites inside the cells. Our results in the current study established satisfactory findings in clearing intracellular L. major parasites in in-vitro conditions. Conclusion: TBO dye in combination with the PDT can be considered as a harmless, effective and importantly perfect treatment against L. major, causative agent of ZCL, in an in-vitro situation without any negative toxicity to the mice macrophages.

The role of the dental surgeon in the early diagnosis of oral cancer: a concise systematic review

Introduction: Oral cancers (OC) represent more than 90% of cases. It is estimated that more than 400,000 new cases of oral cancer are diagnosed each year worldwide. OC is preventable as most of the different identified risk factors, such as tobacco use, alcohol consumption, and betel nut chewing, are behaviors that increase the likelihood of the disease. Surgical biopsy remains the gold standard, but adjunctive tools have been developed to aid diagnoses, such as vital toluidine blue staining and autofluorescence imaging. Objective: To emphasize and present the importance of the dental surgeon in the early diagnosis and prevention of oral cancer. Methods: The survey was conducted from July 2021 to August 2021 and developed based on Scopus, PubMed, Science Direct, Scielo, and Google Scholar, following the rules of Systematic Review-PRISMA. Study quality was based on the GRADE instrument and the risk of bias was analyzed according to the Cochrane instrument. Results: Early detection and treatment of OC were found to be important predictors for improving survival and reducing mortality. A thorough clinical inspection of the oral cavity can detect up to 99% of oral cancers. Other diagnostic types have been developed to help overcome the limits of standard oral clinical examination, highlighting toluidine blue staining, light-based detection techniques, and salivary biomarkers. Self-examination is an effective strategy to reduce the levels of mortality and morbidity caused by this pathology. A gain of 8.09% more in sensitivity and 11.36% more in specificity was observed with the fluorescence test. Conclusion: The findings clearly showed that early diagnosis of oral cancer is essential to increase the chances of cure and survival of patients, avoiding invasive surgical intervention. Currently, there are several diagnostic tools for screening and visual devices for the early detection of oral lesions through auxiliary methods, logically maintaining biopsy as the gold standard.