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Freshwater bodies and, consequently, drinking water treatment plants (DWTPs) sources are increasingly facing toxic cyanobacterial blooms. Even though conventional treatment processes including coagulation, flocculation, sedimentation, and filtration can control cyanobacteria and cell-bound cyanotoxins, these processes may encounter challenges such as inefficient removal of dissolved metabolites and cyanobacterial cell breakthrough. Furthermore, conventional treatment processes may lead to the accumulation of cyanobacteria cells and cyanotoxins in sludge. Pre-oxidation can enhance coagulation efficiency as it provides the first barrier against cyanobacteria and cyanotoxins and it decreases cell accumulation in DWTP sludge. This critical review aims to: (i) evaluate the state of the science of cyanobacteria and cyanotoxin management throughout DWTPs, as well as their associated sludge, and (ii) develop a decision framework to manage cyanobacteria and cyanotoxins in DWTPs and sludge. The review identified that lab-cultured-based pre-oxidation studies may not represent the real bloom pre-oxidation efficacy. Moreover, the application of a common exposure unit CT (residual concentration × contact time) provides a proper understanding of cyanobacteria pre-oxidation efficiency. Recently, reported challenges on cyanobacterial survival and growth in sludge alongside the cell lysis and cyanotoxin release raised health and technical concerns with regards to sludge storage and sludge supernatant recycling to the head of DWTPs. According to the review, oxidation has not been identified as a feasible option to handle cyanobacterial-laden sludge due to low cell and cyanotoxin removal efficacy. Based on the reviewed literature, a decision framework is proposed to manage cyanobacteria and cyanotoxins and their associated sludge in DWTPs.

Conventional processes (coagulation, flocculation, sedimentation, and filtration) are widely used in drinking water treatment plants and are considered a good treatment strategy to eliminate cyanobacterial cells and cell-bound cyanotoxins. The diversity of cyanobacteria was investigated using taxonomic cell counts and shotgun metagenomics over two seasons in a drinking water treatment plant before, during, and after the bloom. Changes in the community structure over time at the phylum, genus, and species levels were monitored in samples retrieved from raw water (RW), sludge in the holding tank (ST), and sludge supernatant (SST). Aphanothece clathrata brevis, Microcystis aeruginosa, Dolichospermum spiroides, and Chroococcus minimus were predominant species detected in RW by taxonomic cell counts. Shotgun metagenomics revealed that Proteobacteria was the predominant phylum in RW before and after the cyanobacterial bloom. Taxonomic cell counts and shotgun metagenomic showed that the Dolichospermum bloom occurred inside the plant. Cyanobacteria and Bacteroidetes were the major bacterial phyla during the bloom. Shotgun metagenomics also showed that Synechococcus, Microcystis, and Dolichospermum were the predominant detected cyanobacterial genera in the samples. Conventional treatment removed more than 92% of cyanobacterial cells but led to cell accumulation in the sludge up to 31 times more than in the RW influx. Coagulation/sedimentation selectively removed more than 96% of Microcystis and Dolichospermum. Cyanobacterial community in the sludge varied from raw water to sludge during sludge storage (1–13 days). This variation was due to the selective removal of coagulation/sedimentation as well as the accumulation of captured cells over the period of storage time. However, the prediction of the cyanobacterial community composition in the SST remained a challenge. Among nutrient parameters, orthophosphate availability was related to community profile in RW samples, whereas communities in ST were influenced by total nitrogen, Kjeldahl nitrogen (N- Kjeldahl), total and particulate phosphorous, and total organic carbon (TOC). No trend was observed on the impact of nutrients on SST communities. This study profiled new health-related, environmental, and technical challenges for the production of drinking water due to the complex fate of cyanobacteria in cyanobacteria-laden sludge and supernatant.

Health-related concerns about cyanobacteria-laden sludge of drinking water treatment plants (DWTPs) have been raised in the past few years. Microscopic taxonomy, shotgun metagenomic sequencing, and microcystin (MC) measurement were applied to study the fate of cyanobacteria and cyanotoxins after controlled sludge storage (stagnation) in the dark in a full-scale drinking water treatment plant within 7 to 38 days. For four out of eight dates, cyanobacterial cell growth was observed by total taxonomic cell counts during sludge stagnation. The highest observed cell growth was 96% after 16 days of stagnation. Cell growth was dominated by potential MC producers such as Microcystis, Aphanocapsa, Chroococcus, and Dolichospermum. Shotgun metagenomic sequencing unveiled that stagnation stress shifts the cyanobacterial communities from the stress-sensitive Nostocales (e.g., Dolichospermum) order towards less compromised orders and potential MC producers such as Chroococcales (e.g., Microcystis) and Synechococcales (e.g., Synechococcus). The relative increase of cyanotoxin producers presents a health challenge when the supernatant of the stored sludge is recycled to the head of the DWTP or discharged into the source. These findings emphasize the importance of a strategy to manage cyanobacteria-laden sludge and suggest practical approaches should be adopted to control health/environmental impacts of cyanobacteria and cyanotoxins in sludge.

The impact of oxidation on mitigation of cyanobacteria and cyanotoxins in drinking water treatment sludge was investigated at the laboratory and treatment plant scales. Two common oxidants, KMnO₄ (5 and 10 mg/L) and H₂O₂ (10 and 20 mg/L) were applied under controlled steady-state conditions. Non-oxidized and oxidized sludge was left to stagnate in the dark for 7 to 38 days. Controlled laboratory trials show that KMnO₄ and H₂O₂ decreased cell counts up to 62% and 77%, respectively. The maximum total MC level reduction achieved after oxidation was 41% and 98% using 20 mg/L H₂O₂ and 10 mg/L KMnO₄, respectively. Stagnation caused cell growth up to 2.6-fold in 8 out of 22 oxidized samples. Microcystin (MC) producer orders as Chroococcales and Synechococcales were persistent while Nostocales was sensitive to combined oxidation and stagnation stresses. In parallel, two on-site shock oxidation treatments were performed in the DWTP’s sludge holding tank using 10 mg/L KMnO₄. On-site shock oxidation decreased taxonomic cell counts by up to 43% within 24 h. Stagnation preceded by on-site shock oxidation could increase total cell counts by up to 55% as compared to oxidation alone. The increase of cell counts and mcyD gene copy numbers during stagnation revealed the impact of oxidation/stagnation on cyanobacterial cell growth. These findings show the limitations of sludge oxidation as a strategy to manage cyanobacteria and cyanotoxins in sludge and suggest that alternative approaches to prevent the accumulation and mitigation of cyanobacteria in sludge should be considered.

Health-related concerns on accumulation of cyanobacteria and cyanotoxins in the sludge of conventional treatment processes (coagulation, flocculation, sedimentation, and filtration) have been raised in drinking water treatment plants (DWTPs) in recent years. The fate of cyanobacteria and cyanotoxins in the sludge is complex due to the simultaneous impact of cyanobacterial composition in the intake water, environmental conditions, and various phenomena such as cell survival, growth, lysis, and cyanotoxin release during sludge storage. However, little information about the dynamics of cyanobacterial shifts from the intake water towards sludge and supernatant, the fate of cyanobacteria and cyanotoxins during sludge storage, and treatment of cyanobacteria-laden sludge is available. The general objective of this research study is to investigate the fate of cyanobacteria and cyanotoxins in the sludge of DWTPs during storage and handling. The specific objectives are to: i) Diagnose critical points of DWTPs where cyanobacteria cells and their associated cyanotoxins accumulate, ii) Determine the relationship between cyanobacterial communities in the intake water, sludge, and sludge supernatant; iii) Determine the impact of nutrients on cyanobacterial community shifts in the intake water, sludge, and sludge supernatant; iv) Compare taxonomic cell counts with shotgun metagenomic sequencing results; v) Validate cyanobacterial cell growth during sludge storage, vi) Study the dynamics of the cyanobacterial compositions in the stored sludge under controlled conditions, vii) Investigate the most resistant and susceptible cyanobacterial genus during sludge storage, viii) Study the potential health impact (i.e. cyanotoxin release) of the genera surviving sludge storage, ix) Investigate the impact of oxidation on cyanobacteria and cyanotoxins in both lab- and full- scales, x) Determine the efficiency of oxidation during sludge storage, xi) Evaluate the impact of oxidation and stagnation on microbial and cyanobacterial communities, xii) Conduct a critical review on the fate of cyanobacteria and cyanotoxins in conventional treatment plants' sludge and during sludge storage and, xiii) Develop an operational decision framework to determine the best practice to minimize risks associated with cyanobacteria and cyanotoxin presence in DWTPs.

The present study was developed to comprehensively analyze experts' views and content of documents focusing on goals and criteria of sustainable waste management system in Tehran, Iran. To this end, the suitable goals for sustainable waste management system in Tehran city were adopted from domestic, national and international documents. For this purpose, 27 national and international documents and 2 domestic documents related to waste management were selected and analyzed by using content analysis according to Gall, 1994. Further, in order to formulate goals in case of bottlenecks and challenges of waste management in Tehran, the focus group technique was used based on Stewart and Shamdasani, 2014. At this stage, 24 key experts in the field of waste management were interviewed in the form of 4 focus groups. Data collection were performed via audio recording and word-for-word implementation of conversations, taking notes and writing field notes. The data collection continued until reaching theoretical saturation. Next, content analysis and coding methods were used to analyze the data. Finally, the goals of waste management were divided into five general categories including: institutional (with emphasis on the integration and inclusion of the key elements of the urban waste management system), technical and infrastructural (with emphasis on the optimization of existing processes in the use of urban waste management technologies), environmental (with emphasis on minimizing the adverse health and environmental effects of the urban waste management system, economic (with emphasis on the economic and financial sustainability of the urban waste management system), and cultural-social (with emphasis on attracting the maximum participation of citizens and service recipients). The results clearly showed that sustainable waste management measures in Tehran should follow these five components in order to reduce the problems caused by unrealistic waste management and make sustainable use of basic, natural, financial and human resources.

Background Two important virulence factors, urease and cagA, play an important role in Helicobacter pylori ( H. pylori ) gastric cancer. Aim of this study was to investigate the expression level and function of ureB and cagA using small interfering RNAs (siRNA). Methods SS1 strain of H. pylori was considered as host for natural transformation. siRNA designed for ureB and cagA genes were inserted in pGPU6/GFP/Neo siRNA plasmid vector to evaluate using phenotypic and genotypic approaches. Then, qPCR was performed for determining inhibition rate of ureB and cagA gene expression. Results The expression levels of siRNA-ureB and siRNA-cagA in the recombinant strain SS1 were reduced by about 5000 and 1000 fold, respectively, compared to the native H. pylori strain SS1. Also, preliminary evaluation of siRNA-ureB in vitro showed inhibition of urea enzyme activity. These data suggest that siRNA may be a powerful new tool for gene silencing in vitro, and for the development of RNAi-based anti- H. pylori therapies. Conclusion Our results show that targeting ureB and cagA genes with siRNA seems to be a new strategy to inhibit urease enzyme activity, reduce inflammation and colonization rate.

Obesity is a health risk characterized by chronic inflammation, and food choices are strongly associated with its etiology. Our objective was to investigate the association between dietary patterns and the healthy eating index (HEI) with the odds of overweight/obesity and related inflammatory markers. Within a population-based case-control study, we collected data and samples from 793 normal-weight and 812 overweight/obese Iranian people (based on either body mass index (BMI) or body surface area (BSA)). Dietary intake and HEI scores were obtained via a validated 124-item food frequency questionnaire. Anthropometric and socioeconomic parameters, as well as blood inflammatory markers, were measured. Participants with higher HEI scores had higher serum high-density lipoprotein-cholesterol (HDL-C) and significantly lower energy intake. Water consumption in the overweight/obese group was significantly lower than in the control group. In the final models using partial correlation and controlling for multiple confounders, there was a significant inverse correlation between HEI and interleukin-4 (IL-4, R = −0.063), IL-1β (R = −0.054), and high-sensitivity C-reactive protein (hs-CRP, R = −0.069). Based on multivariable logistic regression models adjusted for multiple confounders, there was a significant association between HEI as a continuous variable (OR = 0.993, 95% CI: 0.988–0.999) and categorical variable (OR = 0.801, 95% CI: 0.658–0.977) and odds of overweight/obesity across BMI groups. The dietary patterns in the case and control groups however were similar, and we failed to find a significant association between HEI and odds of overweight/obesity based on BSA. Adherence to healthy eating recommendations may be a prudent recommendation to prevent overweight/obesity and keeping inflammatory indicators low.

Introduction The optimal timing for decompressive hemicraniectomy (DHC) after intravenous thrombolysis (IVT) remains unclear. This study in patients with acute ischemic stroke treated with IVT aimed to assess the safety of DHC and patient outcome. Methods Data was extracted from the Tabriz stroke registry from June 2011 up to September 2020. In all, 881 patients were treated with IVT. Among these, 23 patients underwent DH. Six patients were excluded due to symptomatic intracranial hemorrhage (parenchymal hematoma type 2 based on SITS-MOST definition) after IVT, but other types of bleeding after venous thrombolysis, including HI1, HI2, and PH1 were not excluded; so the remaining 17 patients were enrolled in the study. Functional Outcome was defined as the proportion of patients who achieved mRS score of 2–3 (moderate disability), 4–5 (severe disability), or 6 (mortality) at 90 days after stroke. mRSwas assess by trained neurologist at the hospital clinic with direct interview Safety outcome was assessed by comparison of two scans just prior to and after craniectomy. Any new hemorrhage or worsening of previous hemorrhage was reported. Parenchymal hematoma type 2, based on ECASS II definition, was considered as major surgical complication. This study was approved by the local ethics committee of the Tabriz University of Medical Sciences (Ethics Code: IR.TBZMED.REC.1398.420). Results At the three-month mRS follow up, six patients (35%) had moderate and five (29%) had severe disability. The outcome of death was observed in six patients (35%).Nine of 15 patients (60%) underwent surgery in the first 48 hours after onset of symptoms. No patient over 60 years of age survived to the three-month follow up; 67% of those who were under60 years and underwent DH in the first 48 hours had favorable outcome. Hemorrhagic complication was seen in 64% of patients but none was major. Conclusion Results of this study showed that the rate of major bleeding and outcome of acute ischemic stroke patients who underwent DHC after IVT is comparable with the reported data in the literature and intentionally waiting for the fibrinolytic effects of IVT to disappear may not outweigh the benefits of DHC. Although the findings of the study should be interpreted with caution and larger studies are needed to confirm the results.

Low dose ketamine can be used as analgesic in acute pain management in the emergency department (ED). Efficacy of IN ketamine in acute pain management in the ED. This is a double blind randomized clinical trial on patients older than 15 years who needed digital nerve block (DNB). Participants randomly received IN Ketamine (1 ml = 50 mg) or placebo (normal saline, 1 ml) 5 min before DNB. In both groups, patients' pain score was recorded by visual analogue score (VAS) at baseline, after DNB and 45 min after completion of DNB. Adverse effects of ketamine and changes in vital signs were also recorded and compared with placebo group. A total number of 100 patients were enrolled in the study with the median (IQR) age of 36.5 (26) years, including 65 men and 35 women. IN ketamine resulted in less pain compared to placebo after performing DNB and 45 min after the procedure. Median (IQR) basic VAS score was 50 (15) in ketamine group, and 49 (27) in control group. Median (IQR) block pain VAS score was 28.5 (19) in ketamine group and 47.5 (31) in control group. Median (IQR) procedural pain VAS score was 21.5 (16) in ketamine group and 43.5 (29) in control group. Only 7 patients had adverse effects in either group. The findings of this study suggest that IN ketamine can be effective in reducing pain in patients with acute pain, without adding significant side effects.