On-site domestic wastewater treatment system using shredded waste plastic bottles as biofilter media: Pilot-scale study on effluent standards in Bhutan.

In this study, a 1000 L/d capacity one-off on-site wastewater treatment system was operated for over a year as a pilot alternative to the conventional on-site treatment as currently used in urban Bhutan. An up-flow anaerobic sludge blanket (UASB) was used for blackwater treatment (to replace "septic tank followed by an anaerobic biofilter (ABF) (to replace soak pits) for the treatment of a mixture of greywater and UASB effluent. Shredded waste plastic bottles were used as the novel biofilter media in the ABF. During a yearlong operation, the pilot system produced a final treated effluent from ABF with average BOD5 28 mg/L, COD 38 mg/L, TSS 85 mg/L and 5 log units of Escherichia coli. These effluents met three out of four of the national effluent discharge limits of Bhutan, but unsuccessful to meet the Escherichia coli standard over a yearlong operation. Further, process optimisation may enable more significant Escherichia coli removal. An economic analysis indicates that the total unit cost (capital and operating expenditures) of this alternative wastewater treatment system for more than 50 users range between USD 0.27-0.37/person/month comparable to USD 0.29-0.42/person/month for the current predominant on-site system, i.e., "septic tanks". This pilot study, therefore, indicates that this wastewater treatment system using shredded waste plastic biofilter media has high potential to replace the current conventional treatment, i.e., "septic tanks", which are often overloaded with greywater and discharging effluents which does not meet the national standards.

Application of the Bethesda system for reporting thyroid cytopathology for classification of thyroid nodules: A clinical and cytopathological characteristics in Bhutanese population.

INTRODUCTION: The existence of baseline data on the spectrum of thyroid nodules in Bhutanese patients is unknown. Fine-needle aspiration cytology (FNAC) is regarded as the gold standard diagnostic test for pre-op assessment of thyroid lesions. MATERIALS AND METHODS: We conducted a retrospective study, involving 765 patients who underwent FNAC of the thyroid gland, at Jigme Dorji Wangchuck National Referral Hospital, Thimphu, between January-2018 to December-2020. We aimed to assess the cytomorphological spectrum of thyroid nodules, classify them as per The Bethesda system for reporting thyroid cytopathology (TBSRTC), assess risk of malignancy (ROM), and evaluate the accuracy of FNAC in diagnosing thyroid malignancy. RESULTS: Colloid nodule (37.4%) and papillary thyroid carcinoma (4.2%) constituted the majority of benign and malignant cytological diagnoses, respectively. According to TBSRTC, majority of the cases (82.0%) fell under the Bethesda II category. Bethesda III was the least common (1.4%) category. As compared to histopathological diagnosis; the sensitivity, specificity, positive and the negative predictive values of FNAC in diagnosing thyroid malignancy were 90.0%, 93.3%, 93.10%, and 90.32% respectively. The ROM increased concurrently with the grade of the Bethesda category and was more or less close to the ROM reference range, published in the TBSRTC. CONCLUSION: Benign thyroid nodules (82.0%) constituted a majority of thyroid nodules in Bhutanese patients. FNAC was found to be reliable in detecting thyroid malignancy. From the literature, TBSRTC was found to be a more convenient method for reporting thyroid cytology. Henceforth, as most institutes, we plan to implement TBSRTC for reporting thyroid cytopathology.

Epithelial-Mesenchymal Transition Predicts Survival in Oral Squamous Cell Carcinoma.

Synergistic loss of E-cadherin and acquisition of vimentin are characteristic feature of epithelial-mesenchymal transition (EMT) which confers an invasive phenotype of epithelial cancer cells. The aim of the study was to evaluate the prognostic significance of E-cadherin and vimentin expression individually and in combination as a measure of epithelial-mesenchymal transition (EMT) in oral squamous cell carcinoma (OSCC). Expression of E-cadherin and vimentin through immunohistochemical analysis was examined in 200 patients with surgically resected OSCC. Combined E-cadherin and vimentin expression was evaluated to determine the EMT status. Kaplan-Meier curves and log-rank test were used to compare differences in survival. Cox regression analysis was performed to identify independent prognostic factors. E-cadherin expression was negative in 28 (14%) tumors, and vimentin expression was positive in 87 (43.5%) tumors. Moreover, 99 (49.5%), 87 (43.5%), and 14 (7.5%) tumors exhibited no, partial, and complete EMT, respectively. Both individual protein expression were significant prognostic factors [Negative E-cadherin, hazard ratio (HR) = 1.74, 95% confidence interval (CI) = 1.04-2.93; positive vimentin, HR = 1.64, 95% CI = 1.12-2.41]. For EMT status, the HR increased with EMT progression [partial EMT, HR = 1.64, 95% CI = 1.09-2.49; complete EMT, HR = 2.88, 95% CI = 1.44-5.79], of which, the complete EMT had higher HR than was individual protein expression. Combined E-cadherin and vimentin expression as a measure of EMT showed a superior prognostic significance compared with individual protein expression.

In vitro assessment of sex steroids and related compounds in water and sediments - a critical review.

Detection of endocrine disrupting compounds in water and sediment samples has gained much importance since the evidence of their effects was reported in aquatic ecosystems in the 1990s. The aim of this review is to highlight the advances made in the field of in vitro analysis for the detection of hormonally active compounds with estrogenic, androgenic and progestogenic effects in water and sediment samples. In vitro assays have been developed from yeast, mammalian and in a few cases from fish cells. These assays are based either on the hormone-mediated proliferation of sensitive cell lines or on the hormone-mediated expression of reporter genes. In vitro assays in combination with various sample enrichment methods have been used with limits of detection as low as 0.0027 ng L-1 in water, and 0.0026 ng g-1 in sediments for estrogenicity, 0.1 ng L-1 in water, and 0.5 ng g-1 in sediments for androgenicity, and 5 ng L-1 in water for progestogenicity expressed as equivalent concentrations of standard reference compounds of 17ß-estradiol, dihydrotestosterone and progesterone, respectively. The experimental results and limits of quantification, however, are influenced by the methods of sample collection, preparation, and individual laboratory practices.