Characterization of biofilm formation and multi-drug resistance among Pseudomonas aeruginosa isolated from hospital wastewater in Dhaka, Bangladesh.

Hospital wastewater has been identified as a hotspot for the emergence and transmission of multidrug-resistant (MDR) pathogens that present a serious threat to public health. Therefore, we investigated the current status of antibiotic resistance as well as the phenotypic and genotypic basis of biofilm formation in Pseudomonas aeruginosa from hospital wastewater in Dhaka, Bangladesh. The disc diffusion method and the crystal violet assay were performed to characterize antimicrobial resistance and biofilm formation, respectively. Biofilm and integron-associated genes were amplified by the polymerase chain reaction. Isolates exhibited varying degrees of resistance to different antibiotics, in which >80% of isolates showed sensitivity to meropenem, amikacin, and gentamicin. The results indicated that 93.82% of isolates were MDR and 71 out of 76 MDR isolates showed biofilm formation activities. We observed the high prevalence of biofilm-related genes, in which algD+pelF+pslD+ (82.7%) was found to be the prevalent biofilm genotypic pattern. Sixteen isolates (19.75%) possessed class 1 integron (int1) genes. However, statistical analysis revealed no significant association between biofilm formation and multidrug resistance (χ2 = 0.35, P = 0.55). Taken together, hospital wastewater in Dhaka city may act as a reservoir for MDR and biofilm-forming P. aeruginosa, and therefore, the adequate treatment of wastewater is recommended to reduce the occurrence of outbreaks.

Health-related quality of life in women with breast cancer: a review of measures.

BACKGROUND: To identify and describe the breast cancer-specific health-related quality of life (HRQoL) instruments with evidence of validation in the breast cancer population for potential use in patients treated for breast cancer (excluding surgery). METHODS: We conducted a systematic literature review using PubMed, Embase, and PsycINFO databases to identify articles that contain psychometric properties of HRQoL instruments used in patients with breast cancer. Relevant literature from January 1, 2009, to August 19, 2019, was searched. Articles published in English that reported psychometric properties (reliability, validity) of HRQoL instruments were identified. RESULTS: The database search yielded 613 unique records; 131 full-text articles were reviewed; 80 articles presented psychometric data for instruments used in breast cancer (including generic measures). This article reviews the 33 full articles describing psychometric properties of breast cancer-specific HRQoL instruments: EORTC QLQ-C30, EORTC QLQ-BR23, FACT-B, FBSI, NFBSI-16, YW-BCI36, BCSS, QuEST-Br, QLICP-BR, INA-BCHRQoL, and two newly developed unnamed measures, one by Deshpande and colleagues (for use in India) and one by Vanlemmens and colleagues (for use among young women and their partners). The articles that described the EORTC QLQ-C30, QLQ-BR23, and FACT-B centered on validating translations, providing additional support for content validity, and demonstrating acceptability of electronic patient-reported outcome administration. Psychometric properties of the measures were acceptable. Several new measures have been developed in Asia with an emphasis on development on cultural relevance/sensitivity. Others focused on specific populations (i.e., young women with breast cancer). CONCLUSIONS: Historically, there have been limited options for validated measures to assess HRQoL of patients with breast cancer. A number of new measures have been developed and validated, offering promising options for assessing HRQoL in this patient population. This review supports the reliability and validity of the EORTC QLQ-C30 and FACT-B; new translations and electronic versions of these measures further support their use for this population.

QbD Approach towards Robust Design Space for Flutamide/PiperineSelf-Emulsifying Drug Delivery System with Reduced Liver Injury.

Flutamide which is used to treat prostate cancer and other diseases induces liver damage during and after the therapy. The aim of this study was to develop a flutamide/piperineco-loaded self-emulsifying drug delivery system (FPSEDDS) to inhibit flutamide-induced liver injury by utilizing piperine as a metabolic inhibitor. The development of SEDDS was carried out following a quality by design (QbD) approach. The risk assessment study was performed to identify critical quality attributes (CQAs) and critical material attributes (CMAs)/critical process parameters (CPPs). I-optimal mixture design was executed with three CMAs as the independent variables and CQAs as the dependable variables. The effectiveness of optimized SEDDS to circumvent flutamide-induced hepatotoxicity was assessed in mice. The numerical optimization suggested an optimal formulation with a desirability value of 0.621, using CQAs targets as optimization goals with 95% prediction intervals (α = 0.05). The optimal formulation exhibited the grade A SEDDS characteristics with the guarantee of high payloads in self-formed oily droplets. The design space was also obtained from the same optimization goals. All CQA responses of verification points were found within the 95% prediction intervals of the polynomial models, indicating a good agreement between actual versus predicted responses within the design space. These obtained responses also passed CQAs acceptance criteria. Finally, hematoxylin-eosin staining revealed the minimal flutamide-induced hepatotoxicity from the optimal SEDDS formulation as compared to the control and flutamide/piperine normal suspension. We demonstrate that the piperine containing optimized SEDDS formulation developed by QbD significantly reduces the flutamide-induced liver injury in mice.

Prognostic factors of brain metastasis and survival among HER2-positive metastatic breast cancer patients: a systematic literature review.

BACKGROUND: Patients with breast cancer who overexpress the human epidermal growth factor receptor 2 (HER2) and subsequently develop brain metastasis (BM) typically experience poor quality of life and low survival. We conducted a comprehensive literature review to identify prognostic factors for BM and predictors of survival after developing BM, and the effects of therapies with different mechanisms of action among patients with HER2+ breast cancer (BC). METHODS: A prespecified search strategy was used to identify research studies investigating BM in patients with HER2+ BC published in English during January 1, 2009-to June 25, 2021. Articles were screened using a two-phase process, and data from selected articles were extracted. RESULTS: We identified 25 published articles including 4097 patients with HER2+ BC and BM. Prognostic factors associated with shorter time to BM diagnosis after initial BC diagnosis included younger age, hormone receptor negative status, larger tumor size or higher tumor grade, and lack of treatment with anti-HER2 therapy. Factors predictive of longer survival after BM included having fewer brain lesions (< 3 or a single lesion) and receipt of any treatment after BM, including radiosurgery, neurosurgery and/or systemic therapy. Patients receiving combination trastuzumab and lapatinib therapy or trastuzumab and pertuzumab therapy had the longest median survival compared with other therapies assessed in this review. CONCLUSIONS: More research is needed to better understand risk factors for BM and survival after BM in the context of HER2+ BC, as well as the assessment of new anti-HER2 therapy regimens that may provide additional therapeutic options for BM in these patients.

Clinical and laboratory predictors of 30-day mortality in severe acute malnourished children with severe pneumonia.

OBJECTIVE: To determine the predictors of mortality within 30 days of hospital admission in a diarrhoeal disease hospital in Bangladesh. METHODS: Cohort study of hospitalised children aged 0-59 months with severe acute malnutrition (SAM) and severe pneumonia in Dhaka Hospital, icddr,b, Bangladesh from April 2015 to March 2017. Those discharged were followed up, and survival status at 30 days from admission was determined. Children who died were compared with the survivors in terms of clinical and laboratory biomarkers. Multivariable logistic regression analysis was used for calculating adjusted odds ratio for death within 30 days of hospital admission. RESULTS: We enrolled 191 children. Mortality within 30 days of admission was 6% (14/191). After adjusting for potential confounders (hypoxia, CRP and haematocrit) in logistic regression analysis, independent factors associated with death were female sex (aOR = 5.80, 95% CI: 1.34-25.19), LAZ <-4 (aOR = 6.51, 95% CI: 1.49-28.44) and Polymorphonuclear Leucocytes (PMNL) (>6.0 × 109 /L) (aOR = 1.06, 95% CI: 1.01-1.11). Using sex, Z-score for length for age (LAZ), and PMNL percentage, we used random forest and linear regression models to achieve a cross-validated AUC of 0.83 (95% CI: 0.82, 0.84) for prediction of 30-day mortality. CONCLUSIONS: The results of our data suggest that female sex, severe malnutrition (<-4 LAZ) and higher PMNL percentage were prone to be associated with 30-day mortality in children with severe pneumonia. Association of these factors may be used in clinical decision support for prompt identification and appropriate management for prevention of mortality in this population.

OBJECTIF: Déterminer les prédicteurs de mortalité dans les 30 jours suivant l'admission à l'hôpital dans un hôpital pour maladies diarrhéiques au Bangladesh. MÉTHODES: Etude de cohorte d'enfants hospitalisés âgés de 0 à 59 mois atteints de malnutrition aiguë sévère (MAS) et de pneumonie sévère à l'hôpital de Dhaka, icddr,b, au Bangladesh d'avril 2015 à mars 2017. Ceux qui ont été libérés ont été suivis et leur état de survie à 30 jours de l'admission a été déterminé. Les enfants décédés ont été comparés aux survivants en termes de biomarqueurs cliniques et de laboratoire. Une analyse de régression logistique multivariée a été utilisée pour calculer le rapport de cotes ajusté pour le décès dans les 30 jours suivant l'admission à l'hôpital. RÉSULTATS: Nous avons inscrit 191 enfants. La mortalité dans les 30 jours suivant l'admission était de 6% (14/191). Après ajustement pour les facteurs confusionnels potentiels (hypoxie, CRP et hématocrite) dans l'analyse de régression logistique, les facteurs indépendants associés au décès étaient le sexe féminin (aOR = 5,80 ; IC95%: 1,34 à 25,19), LAZ <-4 (aOR = 6,51 ; IC95%: 1,49-28,44) et leucocytes polymorphonucléaires (LPMN) (>6,0 x 109 /L) (aOR = 1,06 ; IC95%: 1,01-1,11). En utilisant le sexe, le score Z de la taille pour l'âge (LAZ) et le pourcentage de LPMN, nous avons utilisé des modèles de régression linéaire et de forest aléatoires pour obtenir une AUC validée croisée de 0,83 (IC95%: 0,82-0,84) pour la prédiction de la mortalité à 30 jours. CONCLUSIONS: Les résultats de nos données suggèrent que le sexe féminin, la malnutrition sévère (LAZ <-4) et un pourcentage plus élevé de LPMN étaient susceptibles d'être associés à la mortalité à 30 jours chez les enfants atteints de pneumonie sévère. L'association de ces facteurs peut être utilisée dans l'aide à la décision clinique pour une identification rapide et une prise en charge appropriée pour la prévention de la mortalité dans cette population.

The general base in the thymidylate synthase catalyzed proton abstraction.

The enzyme thymidylate synthase (TSase), an important chemotherapeutic drug target, catalyzes the formation of 2'-deoxythymidine-5'-monophosphate (dTMP), a precursor of one of the DNA building blocks. TSase catalyzes a multi-step mechanism that includes the abstraction of a proton from the C5 of the substrate 2'-deoxyuridine-5'-monophosphate (dUMP). Previous studies on ecTSase proposed that an active-site residue, Y94 serves the role of the general base abstracting this proton. However, since Y94 is neither very basic, nor connected to basic residues, nor located close enough to the pyrimidine proton to be abstracted, the actual identity of this base remains enigmatic. Based on crystal structures, an alternative hypothesis is that the nearest potential proton-acceptor of C5 of dUMP is a water molecule that is part of a hydrogen bond (H-bond) network comprised of several water molecules and several protein residues including H147, E58, N177, and Y94. Here, we examine the role of the residue Y94 in the proton abstraction step by removing its hydroxyl group (Y94F mutant). We investigated the effect of the mutation on the temperature dependence of intrinsic kinetic isotope effects (KIEs) and found that these KIEs are more temperature dependent than those of the wild-type enzyme (WT). These results suggest that the phenolic -OH of Y94 is a component of the transition state for the proton abstraction step. The findings further support the hypothesis that no single functional group is the general base, but a network of bases and hydroxyls (from water molecules and tyrosine) sharing H-bonds across the active site can serve the role of the general base to remove the pyrimidine proton.

Concerted versus stepwise mechanism in thymidylate synthase.

Thymidylate synthase (TSase) catalyzes the intracellular de novo formation of thymidylate (a DNA building block) in most living organisms, making it a common target for chemotherapeutic and antibiotic drugs. Two mechanisms have been proposed for the rate-limiting hydride transfer step in TSase catalysis: a stepwise mechanism in which the hydride transfer precedes the cleavage of the covalent bond between the enzymatic cysteine and the product and a mechanism where both happen concertedly. Striking similarities between the enzyme-bound enolate intermediates formed in the initial and final step of the reaction supported the first mechanism, while QM/MM calculations favored the concerted mechanism. Here, we experimentally test these two possibilities using secondary kinetic isotope effect (KIE), mutagenesis study, and primary KIEs. The findings support the concerted mechanism and demonstrate the critical role of an active site arginine in substrate binding, activation of enzymatic nucleophile, and the hydride transfer studied here. The elucidation of this reduction/substitution sheds light on the critical catalytic step in TSase and may aid future drug or biomimetic catalyst design.

Kinetic isotope effects as a probe of hydrogen transfers to and from common enzymatic cofactors.

Enzymes use a number of common cofactors as sources of hydrogen to drive biological processes, but the physics of the hydrogen transfers to and from these cofactors is not fully understood. Researchers study the mechanistically important contributions from quantum tunneling and enzyme dynamics and connect those processes to the catalytic power of enzymes that use these cofactors. Here we describe some progress that has been made in studying these reactions, particularly through the use of kinetic isotope effects (KIEs). We first discuss the general theoretical framework necessary to interpret experimental KIEs, and then describe practical uses for KIEs in the context of two case studies. The first example is alcohol dehydrogenase, which uses a nicotinamide cofactor to catalyze a hydride transfer, and the second example is thymidylate synthase, which uses a folate cofactor to catalyze both a hydride and a proton transfer.

Data describing effects of different phosphorus concentrations on growth and chymotrypsin inhibitors in Microcystis aeruginosa NIVA Cya 43 using LC-MS.

Cyanobacteria's abundant production of bioactive compounds concerns unselective filter feeders in the aquatic food chain, but the factors driving this production remain poorly understood. Notably, nutrient availability, particularly concerning phosphorus and nitrogen, is believed to be a pivotal determinant of cyanobacterial mass development. In this data investigation, we aimed to explore the influence of dissolved phosphorus (PO43-) on the presence of chymotrypsin inhibitors, specifically Cyanopeptolin 954 (CP954) and Nostopeptin 920 (BN920), within Microcystis aeruginosa NIVA Cya 43. A carefully controlled 15-day batch culture experiment was conducted, with three distinct phosphate concentrations (30, 50, and 75 µM). Liquid Chromatography-Mass Spectrometry (LC-MS) was employed for quantitative analysis, and the findings underscored the intricate interplay between nutrient availability, particularly phosphorus, and the content of chymotrypsin inhibitors (CP954 and BN920) by Cyanobacteria. More precisely, a significant 53% increase in CP954 content was noticed as the phosphate concentration decreased, revealing the intricate connection between nutrient availability, particularly phosphorus, in Cyanobacteria. Future research should further investigate the impacts of environmental factors, including light intensity and other nutrients like nitrogen, on the content of chymotrypsin inhibitors in Cyanobacteria.

Improvement of Recalcitrant Dissecting Cellulitis of the Scalp After a Trial of Upadacitinib.

Dissecting cellulitis of the scalp (DCS) is a rare condition characterized by painful inflammatory nodules and abscesses on the scalp, often leading to sinus tracts and scarring alopecia. We present a case of DCS in a 26-year-old male who experienced significant clinical improvement following a short course of upadacitinib, a Janus kinase (JAK) inhibitor. The patient received multiple standard treatments such as topical antimicrobials, oral antibiotics, corticosteroids, and intralesional triamcinolone injections, with limited success. However, following the initiation of upadacitinib, the patient reported reduced pain, pustular draining, and bleeding, with significantly improved quality of life. To our knowledge, there is currently a paucity of literature documenting the use of JAK inhibitors for DCS. This case aims to highlight the potential of JAK inhibitors as a therapy for refractory DCS, a condition with limited treatment options.

Polyaromatic Hydrocarbon-Functionalized 2D MXene-Based 3D Porous Antifouling Nanocomposite with Long Shelf Life for High-Performance Electrochemical Immunosensor Applications.

Affinity-based electrochemical (AEC) biosensors have gained more attention in the field of point-of-care management. However, AEC sensing is hampered by biofouling of the electrode surface and degradation of the antifouling material. Therefore, a breakthrough in antifouling nanomaterials is crucial for the fabrication of reliable AEC biosensors. Herein, for the first time, we propose 1-pyrenebutyric acid-functionalized MXene to develop an antifouling nanocomposite to resist biofouling in the immunosensors. The nanocomposite consisted of a 3D porous network of bovine serum albumin cross-linked with glutaraldehyde with functionalized MXene as conductive nanofillers, where the inherited oxidation resistance property of functionalized MXene improved the electrochemical lifetime of the nanocomposite. On the other hand, the size-extruded porous structure of the nanocomposite inhibited the biofouling activity on the electrode surface for up to 90 days in real samples. As a proof of concept, the antifouling nanocomposite was utilized to fabricate a multiplexed immunosensor for the detection of C-reactive protein (CRP) and ferritin biomarkers. The fabricated sensor showed good selectivity over time and an excellent limit of detection for CRP and ferritin of 6.2 and 4.2 pg/mL, respectively. This research successfully demonstrated that functionalized MXene-based antifouling nanocomposites have great potential to develop high-performance and low-cost immunosensors.

Potential biomarkers in breast cancer drug development: application of the biomarker qualification evidentiary framework.

Breast cancer treatments have evolved rapidly, and clinically meaningful biomarkers have been used to guide therapy. These biomarkers hold utility within the drug development process to increase the efficiency and effectiveness. To this purpose, the US FDA developed an evidentiary framework. Literature searches conducted of literature published between 2016 and 2022 identified biomarkers in breast cancer. These biomarkers were reviewed for drug development utility through the biomarker qualification evidentiary framework. In the breast cancer setting, several promising biomarkers (ctDNA, Ki-67 and PIK3CA) were identified. There is a need for increased transparency regarding the requirements for qualification of specific biomarkers and increased awareness of the processes involved in biomarker qualification.

[Box: see text].

Trajectories of resting energy expenditure and performance of predictive equations in children hospitalized with an acute illness and malnutrition: a longitudinal study.

There is scarce data on energy expenditure in ill children with different degrees of malnutrition. This study aimed to determine resting energy expenditure (REE) trajectories in hospitalized malnourished children during and after hospitalization. We followed a cohort of children in Bangladesh and Malawi (2-23 months) with: no wasting (NW); moderate wasting (MW), severe wasting (SW), or edematous malnutrition (EM). REE was measured by indirect calorimetry at admission, discharge, 14-and-45-days post-discharge. 125 children (NW, n = 23; MW, n = 29; SW, n = 51; EM, n = 22), median age 9 (IQR 6, 14) months, provided 401 REE measurements. At admission, the REE of children with NW and MW was 67 (95% CI [58, 75]) and 70 (95% CI [63, 76]) kcal/kg/day, respectively, while REE in children with SW was higher, 79 kcal/kg/day (95% CI [74, 84], p = 0.018), than NW. REE in these groups was stable over time. In children with EM, REE increased from admission to discharge (65 kcal/kg/day, 95% CI [56, 73]) to 79 (95% CI [72, 86], p = 0.0014) and was stable hereafter. Predictive equations underestimated REE in 92% of participants at all time points. Recommended feeding targets during the acute phase of illness in severely malnourished children exceeded REE. Acutely ill malnourished children are at risk of being overfed when implementing current international guidelines.

Isotope effects as probes for enzyme catalyzed hydrogen-transfer reactions.

Kinetic Isotope effects (KIEs) have long served as a probe for the mechanisms of both enzymatic and solution reactions. Here, we discuss various models for the physical sources of KIEs, how experimentalists can use those models to interpret their data, and how the focus of traditional models has grown to a model that includes motion of the enzyme and quantum mechanical nuclear tunneling. We then present two case studies of enzymes, thymidylate synthase and alcohol dehydrogenase, and discuss how KIEs have shed light on the C-H bond cleavages those enzymes catalyze. We will show how the combination of both experimental and computational studies has changed our notion of how these enzymes exert their catalytic powers.

Abundance, characteristics, and spatial-temporal distribution of microplastics in sea salts along the Cox's Bazar coastal area, Bangladesh.

Microplastics (MPs), together with microfibers, have emerged as a contaminant of concern all around the globe. MPs have been detected in freshwater, seawater, sediment, and aquatic species among others. As suggested by several recent investigations, sea salts, a daily intake item by humans, are also contaminated by MPs. The current article describes MPs' occurrence, distribution, type, and timeline variation in raw sea salts from Cox's Bazar, Bangladesh. MPs have been detected in every collected salt sample, and quantity varied from 28.53 ± 2.43 to 93.53 ± 4.21 particles per kg, which was about 52.48 ± 1.72 to 67.46 ± 3.81 µg/kg of raw salt. Microfibers were MPs' dominant shape category, and the plastic types were mainly polyester or nylon. Other types of MPs were polyethylene (PE), polypropylene (PP), polycarbonate (PC), polyurethane (PU), and polystyrene (PS) in decreasing amounts. The majority of the MPs in the sea salts were in the size range of ˂ 3-1 mm. The total amount of MPs and plastic-type variation due to sampling location (p ˃ 0.05) and because of the time period (p ˃ 0.05) was found insignificant. Acetaldehyde, a volatile toxic substance produced by the degradation of polyester polymer chains, was detected in MPs in the range of 0.37 to 1.72 µg/g by headspace GC-MS analysis. Hence, the sea salts contaminated with MPs pose a public health hazard. Microplastics extraction from sea salts and their characterization.

Floating raft culture of Gracilariopsis longissima for optimum biomass yield performance on the coast of Cox's Bazar, Bangladesh.

Seaweed cultivation is an eco-friendly method and attracts growing interest which needs a multi-criteria approach for its sustainability. In our present study, an economically significant red alga, Gracilariopsis longissima was cultured using a floating raft method on the coast of Cox's Bazar, Bangladesh for a period of 90 days from January to March 2022. The effects of different factors such as rope materials, culture type, raft shape, seeding intensity, harvesting phase and water depth on the biomass yield production of G. longissima were evaluated during a 90-day culture period. The biomass yield production and daily growth rate (DGR% day-1) were estimated to evaluate the possibilities of G. longissima cultures in a floating raft culture method. The range of biomass yield production (3.03-13.37 kg/m2) and DGR (3.08-4.72% day-1) is satisfactory in the floating raft culture method. Different water quality variables, the seasonal appearance of epiphytic algae and a cost-benefit analysis of seaweed culture were also performed. A total of eight epiphytic algal species were recorded, which resulted in major challenges for the growth of Gracilariopsis. The per month income for a seaweed farmer was estimated to be US$175.17 for 20 rafts. Our research concluded that farming of G. longissima in the floating raft method could be successfully performed from January to March on the coast of Cox's Bazar.

Removal efficiencies of microplastics of the three largest drinking water treatment plants in Bangladesh.

Drinking water treatment plants (DWTPs) are intended to provide safe water to the municipality, typically by treating surface waters from rivers, lakes, and streams. Regrettably, all of these water sources for DWTPs have been reported to be contaminated by microplastics (MPs). Hence, there is an urgent need to investigate the removal efficiencies of MPs from raw waters in the conventional DWTPs anticipating public health concerns. In this experiment, MPs in the raw and treated waters of the three major DWTPs of Bangladesh, having different water treatment processes, were evaluated. The concentrations of MPs in the inlet points of Saidabad Water Treatment Plant phase-1 and 2 (SWTP-1 and SWTP-2), which share a similar water source of the Shitalakshya River, were 25.7 ± 9.8 and 26.01 ± 9.8 items L-1. The third plant, Padma Water Treatment Plant (PWTP) utilizes water from the Padma River and had an initial MP concentration of 6.2 ± 1.6 items L-1. The studied DWTPs, with their existing treatment processes, were found to reduce the MP loads substantially. The final MP concentrations in treated waters of SWTP-1, SWTP-2, and PWTP were 0.3 ± 0.03, 0.4 ± 0.01, and 0.05 ± 0.02 items L-1 with the removal efficiencies of 98.8, 98.5, and 99.2 %, respectively. The considered size range of MP was 20 µm to <5000. Fragments and fibers were the two predominant MP shapes. In terms of polymer, the MPs were polypropylene (PP, 48 %), polyethylene (PE, 35 %), polyethylene terephthalate (PET, 11 %), and polystyrene (PS, 6 %). The field emission scanning electron microscopy-energy dispersive X-ray spectroscopy (FESEM-EDX) revealed the fractured and rough surfaces of the remaining MPs, which were also found to be contaminated with heavy metals, like lead (Pb), cadmium (Cd), chromium (Cr), arsenic (As), copper (Cu), and zinc (Zn). Hence, additional initiatives are required to remove the residual MPs from the treated waters to safeguard the city dwellers from potential hazards.

Microplastics biodegradation by biofloc-producing bacteria: An inventive biofloc technology approach.

Microplastics pollution has become a threat to aquaculture practices, as nearly all farming systems are saturated with microplastics (MPs) particles. Current research on MPs is limited considering their effects on aquatic organisms and human health. However, limited research has been conducted on potential cures and treatments. In today's world, bioremediation of needful parameters in different culture systems is being successfully practiced by introducing floc-forming bacteria. Researchers had found that some bacteria are efficacious in degrading microplastics particles including polyethylene (PE), polystyrene (PS), and polypropylene (PP). In addition, some bacteria that can form floc, are being used in fish and shellfish culture systems to treat toxic pollutants as the heterotrophic bacteria use organic compounds to grow and are effective in degrading microplastics and minimizing toxic nitrogen loads in aquaculture systems. In this review, the ability of biofloc bacteria to degrade microplastics has been summarized by collating the results of previous studies. The concept of this review may represent the efficacy of biofloc technology as an implicit tool in the fish culture system restricting the MPs contamination in water resources to safeguard ecological as well as human health.

Microplastics pollution in mud crab (Scylla sp.) aquaculture system: First investigation and evidence.

Microplastics (MPs) occurrence in farmed aquatic organisms has already been the prime priority of researchers due to the food security concerns for human consumption. A number of commercially important aquaculture systems have already been investigated for MPs pollution but the mud crab (Scylla sp.) aquaculture system has not been investigated yet even though it is a highly demanded commercial species globally. This study reported the MPs pollution in the mud crab (Scylla sp.) aquaculture system for the first time. Three different stations of the selected aquafarm were sampled for water and sediment samples and MPs particles in the samples were isolated by the gravimetric analysis (0.9% w/v NaCl solution). MP abundance was visualized under a microscope along with their size, shape, and color. A subset of the isolated MPs was analyzed by scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR) for the surface and chemical characterization respectively. The average MPs concentration was 47.5 ± 11.875 particles/g in sediment and 127.92 ± 14.99 particles/100 L in the water sample. Fibrous-shaped (72.17%) and transparent-colored (59.37%) MPs were dominant in all the collected samples. However, smaller MPs (>0.05-0.5 mm) were more common in the water samples (47.69%) and the larger (>1-5 mm) MPs were in the sediment samples (47.83%). SEM analysis found cracks and roughness on the surface of the MPs and nylon, polyethylene, polypropylene, and polystyrene MPs were identified by FTIR analysis. PLI value showed hazard level I in water and level II in sediment. The existence of deleterious MPs particles in the mud crab aquaculture system was well evident. The other commercial mud crab aquafarms must therefore be thoroughly investigated in order to include farmed mud crabs as an environmentally vulnerable food security concern.

Satratoxin-G from the black mold Stachybotrys chartarum induces rhinitis and apoptosis of olfactory sensory neurons in the nasal airways of rhesus monkeys.

Satratoxin-G (SG) is a trichothecene mycotoxin of Stachybotrys chartarum, the black mold suggested to contribute etiologically to illnesses associated with water-damaged buildings. We have reported that intranasal exposure to SG evokes apoptosis of olfactory sensory neurons (OSNs) and acute inflammation in the nose and brain of laboratory mice. To further assess the potential human risk of nasal airway injury and neurotoxicity, we developed a model of SG exposure in monkeys, whose nasal airways more closely resemble those of humans. Adult, male rhesus macaques received a single intranasal instillation of 20 µg SG (high dose, n = 3), or 5 µg SG daily for four days (repeated low dose, n = 3) in one nasal passage, and saline vehicle in the contralateral nasal passage. Nasal tissues were examined using light and electron microscopy and morphometric analysis. SG induced acute rhinitis, atrophy of the olfactory epithelium (OE), and apoptosis of OSNs in both groups. High-dose and repeated low-dose SG elicited a 13% and 66% reduction in OSN volume density, and a 14-fold and 24-fold increase in apoptotic cells of the OE, respectively. This model provides new insight into the potential risk of nasal airway injury and neurotoxicity caused by exposure to water-damaged buildings.