Toward Green Chemical Engineering

The chemicals industry and other related industries supply us with a huge variety of essential products to everyday living. However, these industries have the potential to seriously damage our environment. In the last decade, the scientific community has witnessed a growing interest in environmental issues and the value of environmentally friendly energy generation and chemical processes. The combination of chemical engineering tools with the findings of green chemists, biologists, and environmental scientists has allowed the design of new processes for the manufacture of chemicals, fuels, and products with a much reduced environmental footprint. Furthermore, the developed environmentally benign alternative technologies have been proven to be economically superior and function as well as or better than more toxic traditional optionsMinisterio de Ciencia e Innovación

RESPONSE SURFACE METHODOLOGY APPLIED TO LACCASES ACTIVITIES EXHIBITED BY STENOTROPHOMONAS MALTOPHILIA AAP56 IN DIFFERENT GROWTH CONDITIONS

Stenotrophomonas maltophilia AAP56, laccase-producing bacteria, growing under different conditions, exhibit laccase activity that is highly affected by some environmental factors. Response surface methodology (RSM) was applied for the determination of laccase factor dependence using two substrates: ABTS (2,2’-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)) and DMP (2,6 Dimethoxy-phenol). RSM was carried out with a 24 factorial design using four variables, namely, dye (0 to 0.1 mg mL-1), Cu in Med (0 to 400 µM), shaking (0 to 150 rpm), and CuSO4 in assay (0 to 0.2 mM). Significant correlation between the effects of these variables on R1 (ABTS oxidase activity) and R2 (DMP oxidase activity) responses was detected. Astonishing results showed differences between these two activities with respect to copper activity dependence. Anoxic conditions exhibited a significant ability to induce the enzyme. This bacterial laccase activity (produced under optimal conditions according to RSM) was used to decolorize an azoic dye, Reactive Black 5 (RB5). It was efficient only in the presence of a redox mediator to degrade RB5 after 20 min of incubation time

Sub-acute intravenous exposure to Fe2O3 nanoparticles does not alter cognitive performances and catecholamine levels, but slightly disrupts plasma iron level and brain iron content in rats

International audienceEngineered nanomaterials are used in various applications due to their particular properties. Among them, Iron Oxide Nanoparticles (Fe2O3-NPs) are used in Biomedicine as theranostic agents i.e. contrast agents in Magnetic Resonance Imaging and cancer treatment. With the increasing production and use of these Fe2O3-NPs, there is an evident raise of Fe2O3-NPs exposure and subsequently a higher risk of adverse outcomes for the environment and Human. In the present paper, we investigated the effects of an intravenous daily Fe2O3-NPs exposure on Wistar rat for one week. As results, we showed that several hematological parameters and transaminase (ALT and AST) levels as well as organ histology remained unchanged in treated rats. Neither the catecholamine levels nor the emotional behavior and learning / memory capacities of rats were impacted by the sub-acute intravenous exposure to Fe2O3-NPs. However, iron level in plasma and iron content homeostasis in brain were disrupted after this exposure. Thus, our results demonstrated that Fe2O3-NPs could have transient effects on rat but the intravenous route is still safer that others which is encouraging for their use in medical and/or biological applications

Olea europaea L. leaf extract mitigates oxidative and histological damage in rat heart tissue exposed to combined noise and toluene: An experimental study

In many occupational settings, workers are frequently exposed to toluene and noise. However, the individual and combined effects of these exposures on the cardiovascular system have not been fully elucidated. Therefore, this study aimed to investigate the impact of simultaneous exposure to toluene and noise on the rat heart, while also evaluating the potential preventive effect of olive leaf extract (OLE). Forty-eight male Wistar rats were randomly assigned to eight groups (n = 6/group): control group (C), control group that received OLE (C + OLE), group exposed to noise (N), group exposed to noise and receiving OLE (N + OLE), group exposed to toluene (T), group exposed to toluene and receiving OLE (T + OLE), group co-exposed to noise and toluene (NT), and group co-exposed to noise and toluene and receiving OLE (NT + OLE). The rats in this study were subjected to simultaneous exposure to toluene and noise for a duration of six weeks, within a custom-built plexiglass chamber. Toluene was administered at a concentration of 300 ppm, while the noise level was set to 85 dB(A). The exposure chamber was equipped with a generation system, an exposure system, and a monitoring system, ensuring precise and accurate exposure conditions. After the six-week period, heart and blood samples were collected from the rats for subsequent analysis. Plasma levels of cholesterol (CHOL), triglycerides (TG), lactate dehydrogenase (LDH), and creatine kinase (CK) were measured, and histopathological investigation was conducted using HE staining. Additionally, superoxide dismutase (SOD) and catalase (CAT) activities, as well as malondialdehyde (MDA) levels in heart tissue were measured. Our results showed that simultaneous exposure to noise and toluene altered CHOL, TG, LDH, and CK levels, and also caused an increase in lipid peroxidation levels and superoxide dismutase activity, along with a decrease in catalase activity in the heart. A significant alteration in the myocardium was also observed. However, treatment with OLE was found to modulate these oxidative and histological changes, ultimately correcting the deleterious effects induced by the combined exposure to noise and toluene. Therefore, our study suggests that OLE could be a potential preventive measure for individuals exposed to toluene and noise in industrial settings

Intranasal instillation of iron oxide nanoparticles induces inflammation and perturbation of trace elements and neurotransmitters, but not behavioral impairment in rats

International audienceOver the last decades, engineered nanomaterials have been widely used in various applications due to their interesting properties. Among them, iron oxide nanoparticles (IONPs) are used as theranostic agents for cancer, and also as contrast agents in magnetic resonance imaging. With the increasing production and use of these IONPs, there is an evident raise of IONP exposure and subsequently a higher risk of adverse outcome for humans and the environment. In this work, we aimed to investigate the effects of sub-acute IONP exposure on Wistar rat, particularly (i) on the emotional and learning/memory behavior, (ii) on the hematological and biochemical parameters, (iii) on the neurotransmitter content, and (vi) on the trace element homeostasis. Rats were treated during seven consecutive days by intranasal instillations at a dose of 10 mg/kg body weight. The mean body weight increased significantly in IONP-exposed rats. Moreover, several hematological parameters were normal in treated rats except the platelet count which was increased. The biochemical study revealed that phosphatase alkaline level decreased in IONP-exposed rats, but no changes were observed for the other hepatic enzymes (ALT and AST) levels. The trace element homeostasis was slightly modulated by IONP exposure. Sub-acute intranasal exposure to IONPs increased dopamine and norepinephrine levels in rat brain; however, it did not affect the emotional behavior, the anxiety index, and the learning/memory capacities of rats

MPC2 variants disrupt mitochondrial pyruvate metabolism and cause an early-onset mitochondriopathy

International audiencePyruvate is an essential metabolite produced by glycolysis in the cytosol and must be transported across the inner mitochondrial membrane into the mitochondrial matrix, where it is oxidized to fuel mitochondrial respiration. Pyruvate import is performed by the mitochondrial pyruvate carrier (MPC), a hetero-oligomeric complex composed by interdependent subunits MPC1 and MPC2. Pathogenic variants in the MPC1 gene disrupt mitochondrial pyruvate uptake and oxidation and cause autosomal-recessive early-onset neurological dysfunction in humans. The present work describes the first pathogenic variants in MPC2 associated with human disease in four patients from two unrelated families. In the first family, patients presented with antenatal developmental abnormalities and harboured a homozygous c.148T>C (p.Trp50Arg) variant. In the second family, patients that presented with infantile encephalopathy carried a missense c.2T>G (p.Met1?) variant disrupting the initiation codon. Patient-derived skin fibroblasts exhibit decreased pyruvate-driven oxygen consumption rates with normal activities of the pyruvate dehydrogenase complex and mitochondrial respiratory chain and no defects in mitochondrial content or morphology. Re-expression of wild-type MPC2 restored pyruvate-dependent respiration rates in patient-derived fibroblasts. The discovery of pathogenic variants in MPC2 therefore broadens the clinical and genetic landscape associated with inborn errors in pyruvate metabolism

Antiretroviral drug use and HIV drug resistance in female sex workers in Tanzania and the Dominican Republic.

ObjectiveFemale sex workers (FSW) have increased risk of HIV infection. Antiretroviral treatment (ART) can improve HIV outcomes and prevent HIV transmission. We analyzed antiretroviral (ARV) drug use and HIV drug resistance among HIV-positive FSW in the Dominican Republic and Tanzania.MethodsPlasma samples collected at study entry with viral loads >1,000 copies/mL were tested for ARV drugs and HIV drug resistance. ARV drug testing was performed using a qualitative assay that detects 22 ARV drugs in five classes. HIV genotyping was performed using the ViroSeq HIV-1 Genotyping System. Phylogenetic analyses were performed to determine HIV subtype and assess transmission clusters.ResultsAmong 410 FSW, 144 (35.1%) had viral loads >1,000 copies/mL (DR: n = 50; Tanzania: n = 94). ARV drugs were detected in 36 (25.0%) of 144 samples. HIV genotyping results were obtained for 138 (95.8%) cases. No transmission clusters were observed in either country. HIV drug resistance was detected in 54 (39.1%) of 138 samples (31/35 [88.6%] with drugs detected; 23/103 [22.3%] without drugs detected); 29/138 (21.0%) had multi-class resistance (MCR). None with MCR had integrase strand transfer inhibitor resistance. In eight cases, one or more ARV drug was detected without corresponding resistance mutations; those women were at risk of acquiring additional drug resistance. Using multivariate logistic regression, resistance was associated with ARV drug detection (pConclusionsIn this cohort, many women were on ART, but were not virally suppressed. High levels of HIV drug resistance, including MCR, were observed. Resistance was associated with detection of ARV drugs, self-report of ART with full or partial adherence, and duration of HIV infection. These findings highlight the need for better HIV care among FSW to improve their health, reduce HIV drug resistance, and decrease risk of transmission to others