Hasil untuk "Toxicology. Poisons"

Mulaguri Susairaj Veena Anasthasia, Chokkalingam Mansiya, Venu Kannappan et al.

Background: Antimicrobial activity has been reported against a range of bacteria, including multidrug-resistant strains for silver nanoparticles (AgNPs) due to penetration of NPs into the cell. AgNPs can be used in combination with other antibacterial agents to create a synergistic effect. Objective: The present work aims at the preparation of AgNPs in methanol extracts of the dried bark powder of two medicinally important plants, viz., Pongamiapinnata (PP) and Azadirachtaindica (AI) and their therapeutic uses. Method: UV-visible, FTIR spectral techniques and SEM images were used to characterize the NPs. These bio-NPs were tested for this response against mycobacteria such as Streptomycin and Fluconazole, viruses, bacteria, and fungi. Results: Antibacterial activity, antifungal activity and detailed molecular interaction between the therapeutic constituents of PP and AI against Human Mixtard Insulin (HMI) and Histamine were studied by in silico docking analysis. The antimicrobial studies of both PP and AI yielded positive results in our attempt to investigate the mycobacterial study against two human pathogenic organisms. Conclusion: Extensive in-silico docking study showed that the decreasing order of non-covalent interactions of four therapeutic components is Isopongachromene > Karanjin > Quercetin > Azadirachtin against Insulin and Isopongachromene > Azadirachtin > Karanjin > Quercetin against Histamine.

Gracia Luque, Pilar Ortiz, Alfonso Torres-Sánchez et al.

Dietary exposure to the plasticiser bisphenol A (BPA), an obesogenic and endocrine disruptor from plastic and epoxy resin industries, remains prevalent despite regulatory restriction and food safety efforts. BPA can be accumulated in humans and animals, potentially exerting differential health effects based on individual metabolic capacity. This pilot study examines the impact of direct ex vivo BPA exposure on the gut microbiota of obese and normal-weight children, using 16S rRNA amplicon sequencing and anaerobic culturing combined methods. Results showed that direct xenobiotic exposure induced modifications in microbial taxa relative abundance, community structure, and diversity. Specifically, BPA reduced the abundance of bacteria belonging to the phylum <i>Bacteroidota</i>, while taxa from the phylum <i>Actinomycetota</i> were promoted. Consistently, <i>Bacteroides</i> species were classified as sensitive to BPA, whereas bacteria belonging to the class <i>Clostridia</i> were identified as resistant to BPA in our culturomics analysis. Some of the altered bacterial abundance patterns were common for both the BPA-exposed groups and the obese non-exposed group in our pilot study. These findings were also corroborated in a larger cohort of children. Future research will be essential to evaluate these microbial taxa as potential biomarkers for biomonitoring the effect of BPA and its role as an obesogenic substance in children.

Rawan Abudalo, Omar Gammoh, Sara Altaber et al.

Sacheta Sudhendra Kulkarni, Venkatesh R, Anuradha Das et al.

Background: Pharmacogenomics (PGx), a pivotal branch of personalized medicine, studies how genetic variations influence drug responses. Despite its transformative potential, the adoption of PGx in Indian clinical practice faces challenges, such as the lack of population-specific data, evidence-based guidelines, and complexities in interpreting genomic reports. Comprehensive datasets tailored to Indian patients are essential to facilitate the integration of PGx into clinical settings. Methodology: The study collates pharmacogenomic data from multiple sources, including essential drugs listed by the World Health Organization (WHO), drugs used in neonatal intensive care units (NICUs), minimum sets of alleles recommended by the Association for Molecular Pathology (AMP), and catalogs the allele frequencies from the IndiGenomes database to address gaps in actionable PGx for the Indian population. Curated datasets were used to identify pharmacogenomic variants relevant to clinical practice. Results: Overall, 24 prime genes are essential for the outcomes of 57 drugs. In adults, 18 genes influence the metabolism of 44 drugs whereas, in pediatric populations, genotypes of 18 genes significantly impact the metabolism of 18 drugs. Two over-the-counter drugs with actionable PGx variants were identified: ibuprofen and omeprazole. These findings emphasize the clinical relevance of PGx for commonly used drugs, underscoring the need for population-specific data. Conclusions: As the data of several Indian human genome projects become available, an overarching need exists to establish and regulate the dynamic actionable PGx in Indian clinical practice. This will facilitate the integration of pharmacogenomic data into healthcare, enabling effective and personalized drug therapies.

Maryam Mehrzadian, Morteza Andalib Koraim, Elham Zarghami

The purpose of this study was to fitness of causal-structural relationships of quality of work life and self- control with job burnout by mediating self-compassion and emotional regulation strategies in Faraja Corona nurses. Materials and methods: The current research project is applied and descriptive-correlative in nature and structural equation modeling. The statistical population of this research was all the nurses working in the infectious disease (Covid-19) department of two military hospitals in Tehran in the winter of 1400. 300 nurses working in the Covid-19 wards were selected from the above statistical population based on available sampling. To measure the variables, burnout inventory of Maslach and et al (1986), quality of work life questionnaire of Walton and et al (1973), self-control scale of Tangney and et al (2004), short form of the self-compassion scale of Raes and et al (2011), cognitive emotion rregulation questionnaire of Garnefski and Kraaij (2007) were used. Data were analyzed using Pearson correlation and structural equation modelling with using SPSS-24 and AMOS software was investigated. FINDINGS: The results showed that there is a positive and significant relationship between personality types and adaptive cognitive emotional regulation with job burnout (P <0.01). Also, based on the results of the structural model, the direct paths of this research were significant, and the indirect paths of the quality of work life and self-control through the mediating role of self-compassion and adjustment strategies on job burnout were significant and had a good fit (RMSEA=0/016, P-value<0/05). Conclusion: Based on the results, each of the components has a direct effect on job burnout, and the quality of work life and self-control components have an indirect effect on nurses' job burnout through the mediation of emotion regulation strategies and self-compassion. Increasing the skill of emotion regulation strategies and self-compassion and knowing the factors affecting self- compassion in nurses is an important step in reducing job burnout and improving the quality of work life and productivity in nurses

Mohammed A. Alqahtani, Mahmoud A. El-Ghiaty, Sara R. El-Mahrouk et al.

The detoxification of quinones through NAD(P)H:quinone oxidoreductase (NQO1) is a crucial mechanism to maintain cellular homeostasis. The exposure to heavy metals, specifically methylmercury (MeHg), induces several antioxidant enzymes, including NQO1. The nuclear factor erythroid 2-related factor-2 (NRF2) is known to regulate the expression of Nqo1 gene and also the aryl hydrocarbon receptor (AHR) is another Nqo1 gene regulator. This co-regulation prompted us to investigate which transcription factor (NRF2 or AHR) orchestrates the regulation of NQO1 expression upon MeHg exposure. Therefore, we investigated how MeHg can modulate the level of NQO1 expression by exposing Hepa-1c1c7 cells to several concentrations of MeHg with and without the addition of NQO1 inducers, DL-sulforaphane (SUL) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). We found that the mRNA expression of Nqo1 is up-regulated by MeHg in time- as well as dose-dependent fashions. Additionally, MeHg increased the NQO1 at all expression levels with and without the presence of its inducers, SUL or TCDD. Furthermore, the MeHg-mediated increase of NQO1 expression was in parallel with a concurrent increase in the nuclear localization of NRF2 protein, but not that of AHR. Mechanistically, the antioxidant response element-driven reporter gene activity was induced by 215% upon MeHg exposure. Also, transfecting Hepa-1c1c7 with Nrf2 siRNA reduced the MeHg-induced NQO1 protein expression by 60%. In conclusion, our findings provide evidence supporting the hypothesis that MeHg upregulates the Nqo1 gene through a transcriptional mechanism at least in part via a NRF2-dependent mechanism.

Baoyu ZHU, Dan ZHANG, Zhanhui LIANG et al.

BackgroundLong working hours is harmful to the physical and mental health of occupational groups, and should receive active attention. ObjectiveTo evaluate the current status of long working hours among operation and maintenance workers of power supply enterprises, and explore its effects on work-related musculoskeletal disorders (WMSDs) of the population. MethodsFrom March to June 2021, a cross-sectional survey was conducted among 1433 operation and maintenance workers from 10 power supply enterprises in Jilin Province, Shandong Province, and Tianjin Municipality using cluster sampling. A total of 1433 copies of revised Mus-culoskeletal Disorders Questionnaire were distributed, 1343 questionnaires were recovered, and the recovery rate was 93.72%. The questionnaire included general information, personal health behaviors, weekly working hours, work-related factors, and musculoskeletal pain or discomfort in nine body parts in the past 12 months. χ2 test and multiple logistic regression models were used to investigate the relationships between long working hours (>40 h per week) and WMSDs. ResultsThe average age of the workers was (39.42±9.89) years, and the average work experience was 11.00 (5.00, 21.00) years. There were 1158 males (86.22%) and 185 females (13.78%). The average weekly working hours of the workers were (47.98±11.35) h, and the proportion of long working hours (>40 h per week) was 61.06% (820/1343). The proportions of long working hours were higher among the workers with characteristics of male, power distribution, shift work, often/very often long-time standing, often/very often holding awkward postures, often handling heavy objects, limited space to operate, long-time neck tilting backward, keeping arms above shoulders, frequent elbow bending, repeating knee movement every minute, and repeating lower limb or foot movement every minute (all P<0.05). The prevalence rate of WMSDs was 81.53% (1095/1343) among the workers. The results of multiple logistic regression showed that after adjusting education, smoking, exercise, awkward postures, often handling heavy objects, limited space to operate, long-time heavy trunk bending, long-time neck tilting backward, and keeping arms above shoulders, compared with working ≤40 h per week, the risk of WMSDs among workers working >49 h per week was higher (OR=1.406, 95%CI: 1.011-1.955). ConclusionLong working hours is prominent among operation and maintenance workers of power supply enterprises, and increases the risk of reporting WMSDs.

Violaine Sironval, Vittoria Scagliarini, Sivakumar Murugadoss et al.

Abstract Background Li-ion batteries (LIB) are used in most portable electronics. Among a wide variety of materials, LiCoO2 (LCO) is one of the most used for the cathode of LIB. LCO particles induce oxidative stress in mouse lungs due to their Co content, and have a strong inflammatory potential. In this study, we assessed the mutagenic potential of LCO particles in lung cells in comparison to another particulate material used in LIB, LTO (Li4Ti5O12), which has a low inflammatory potential compared to LCO particles. Results We assessed the mutagenic potential of LCO and LTO particles in vitro by performing a cytokinesis-block micronucleus (MN) assay with rat lung epithelial cells (RLE), as well as in vivo in alveolar type II epithelial (AT-II) cells. LCO particles induced MN in vitro at non-cytotoxic concentrations and in vivo at non-inflammatory doses, indicating a primary genotoxic mechanism. LTO particles did not induce MN. Electron paramagnetic resonance and terephthalate assays showed that LCO particles produce hydroxyl radicals (•OH). Catalase inhibits this •OH production. In an alkaline comet assay with the oxidative DNA damage repair enzyme human 8-oxoguanine DNA glycosylase 1, LCO particles induced DNA strand breaks and oxidative lesions. The addition of catalase reduced the frequency of MN induced by LCO particles in vitro. Conclusions We report the mutagenic activity of LCO particles used in LIB in vitro and in vivo. Our data support the role of Co(II) ions released from these particles in their primary genotoxic activity which includes the formation of •OH by a Fenton-like reaction, oxidative DNA lesions and strand breaks, thus leading to chromosomal breaks and the formation of MN. Documenting the genotoxic potential of the other LIB particles, especially those containing Co and/or Ni, is therefore needed to guarantee a safe and sustainable development of LIB.

Tonje Skuland, Marit Låg, Arno C. Gutleb et al.

Abstract Background Silica nanoparticles (SiNPs) are among the most widely manufactured and used nanoparticles. Concerns about potential health effects of SiNPs have therefore risen. Using a 3D tri-culture model of the alveolar lung barrier we examined effects of exposure to SiNPs (Si10) and crystalline silica (quartz; Min-U-Sil) in the apical compartment consisting of human alveolar epithelial A549 cells and THP-1-derived macrophages, as well as in the basolateral compartment with Ea.hy926 endothelial cells. Inflammation-related responses were measured by ELISA and gene expression. Results Exposure to both Si10 and Min-U-Sil induced gene expression and release of CXCL8, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α) and interleukin-1β (IL-1β) in a concentration-dependent manner. Cytokine/chemokine expression and protein levels were highest in the apical compartment. Si10 and Min-U-Sil also induced expression of adhesion molecules ICAM-1 and E-selectin in the apical compartment. In the basolateral endothelial compartment we observed marked, but postponed effects on expression of all these genes, but only at the highest particle concentrations. Geneexpressions of heme oxygenase-1 (HO-1) and the metalloproteases (MMP-1 and MMP-9) were less affected. The IL-1 receptor antagonist (IL-1RA), markedly reduced effects of Si10 and Min-U-Sil exposures on gene expression of cytokines and adhesion molecules, as well as cytokine-release in both compartments. Conclusions Si10 and Min-U-Sil induced gene expression and release of pro-inflammatory cytokines/adhesion molecules at both the epithelial/macrophage and endothelial side of a 3D tri-culture. Responses in the basolateral endothelial cells were only induced at high concentrations, and seemed to be mediated by IL-1α/β released from the apical epithelial cells and macrophages.

Lindsay Ellsworth, Harlan McCaffery, Sergei Chernyak et al.

Background: Infant exposure to environmental chemicals, such as polychlorinated biphenyls (PCBs), may contribute to developmental programming of long-term metabolic disease risk. PCBs persist given their lipophilicity and long half-lives, allowing them to bio-accumulate in adipose tissue. These compounds can then be excreted into maternal milk resulting in infant exposure. Objective: To determine the level of PCBs in milk from mothers with pre-pregnancy overweight and obese (OW/OB) versus normal weight status (NW) and evaluate the association of milk PCB levels with infant growth over the first 6 months of life. Methods: A pilot study of a subset of milk samples from mothers with NW (pre-pregnancy body mass index (BMI) < 25 kg/m2, n = 11) and OW/OB (pre-pregnancy BMI ≥ 25 kg/m2, n = 8) were examined approximately 2-weeks postpartum. PCB congeners 138 + 163, 132 + 153, 180, and the sum were measured using gas chromatography/mass spectrometry and adjusted for milk fat content. Infant growth was monitored from birth to 6 months for weight-for-age (WFA), length-for-age (LFA), weight-for-length (WFL), head circumference-for-age (HCA), and associations with milk PCB content determined using linear mixed modeling. Results: Total milk fat content did not differ by maternal weight status (p = 0.88). Milk from mothers with OW/OB had significantly higher PCB sum (p = 0.02) and PCB 138 + 163 (p = 0.03). PCB 132 + 153 (β −0.0008, p = 0.0218), PCB 180 (β −0.0010, p = 0.0279), and PCB sum (β −0.0006, p = 0.0138) were negatively associated with HCA Z-score growth to 6 months. PCB 180 was negatively associated with infant WFA (β −0.0015, p = 0.0058) and WFL Z-score (β −0.0016, p = 0.0263) to 6 months. There were no associations of PCB sum content with WFL, LFA, WFL Z-score over the first 6 months of life. Conclusions: Maternal overweight and obesity are associated with higher levels of total PCB congeners (132, 138, 153, 163, 180) in human milk. PCB congeners have negative associations with infant head circumference and weight trajectory over the first 6 months of life.

Dan Liu, Biao Jin, Wei Chen et al.

Abstract Background Dipeptidyl peptidase 4 (DPP-4) inhibitors are newer oral anti-diabetic agents which have been approved by the Food and Drug Administration for the treatment of patients with type 2 diabetes mellitus (T2DM). In this analysis, we aimed to systematically compare the cardiovascular outcomes associated with DPP-4 inhibitors versus non-DPP-4 inhibitor users. Methods All English publications that compared the use of DPP-4 inhibitors and that reported cardiovascular outcomes in patients with T2DM were searched using specific terms. Studies were included if they satisfied the following inclusion criteria: They were randomized trials or observation cohorts/registries comparing DPP-4 inhibitors use in patients with T2DM; The studies included a large sample size of participants; And they reported cardiovascular outcomes as their main endpoints. RevMan 5.3 was used to analyze the data, and odds ratios (OR) with 95% confidence intervals (CI) were used to represent the results. Results A total number of 157,478 participants with T2DM were included. Seventy-six thousand and twenty six patients were assigned to the DPP-4 inhibitor group whereas 81,452 patients were assigned to the control group. Results of the current analysis showed that during a mean follow-up time period ranging from 52 to 152 weeks, the primary endpoint (cardiovascular death/non-fatal myocardial infarction (MI)/non-fatal stroke) was not significantly different in the treatment of T2DM patients with versus without DPP-4 inhibitors (OR: 0.95, 95% CI: 0.86–1.04; P = 0.26). Cardiovascular death (OR: 1.00, 95% CI: 0.90–1.10; P = 0.93), stroke (OR: 1.03, 95% CI: 0.89–1.18; P = 0.72), MI (OR: 0.97, 95% CI: 0.88–1.07; P = 0.59), all-cause mortality (OR: 0.84, 95% CI: 0.59–1.18; P = 0.31), hospitalization for cardiovascular complications (OR: 1.02, 95% CI: 0.96–1.09; P = 0.45) and hospitalization specifically for heart failure (OR: 1.05, 95% CI: 0.90–1.23; P = 0.55) were also similarly manifested in both groups. Conclusion The current analysis showed that treatment with DPP-4 inhibitors did not significantly increase cardiovascular outcomes in these patients with T2DM indicating that those drugs might be safe to use in terms of cardiovascular events.

Roghayeh Mozafari, Sergiy Kyrylenko, Mateus Vidigal Castro et al.

Abstract Background Peripheral nerve injury is a worldwide clinical problem, and the preferred surgical method for treating it is the end-to-end neurorrhaphy. When it is not possible due to a large nerve gap, autologous nerve grafting is used. However, these surgical techniques result in nerve regeneration at highly variable degrees. It is thus very important to seek complementary techniques to improve motor and sensory recovery. One promising approach could be cell therapy. Transplantation therapy with human embryonic stem cells (hESCs) is appealing because these cells are pluripotent and can differentiate into specialized cell types and have self-renewal ability. Therefore, the main objective of this study was to find conditions under which functional recovery is improved after sciatic nerve neurorrhaphy. We assumed that hESC, either alone or in combination with heterologous fibrin sealant scaffold, could be used to support regeneration in a mouse model of sciatic nerve injury and repair via autografting with end-to-end neurorrhaphy. Methods Five millimeters of the sciatic nerve of C57BL/6 J mice were transected off and rotated 180 degrees to simulate an injury, and then stumps were sutured. Next, we applied heterologous fibrin sealant and/or human embryonic stem cells genetically altered to overexpress fibroblast growth factor 2 (FGF2) at the site of the injury. The study was designed to include six experimental groups comprising neurorrhaphy (N), neurorrhaphy + heterologous fibrin sealant (N + F), neurorrhaphy + heterologous fibrin sealant + doxycycline (N + F + D), neurorrhaphy + heterologous fibrin sealant + wild-type hESC (N + F + W), neurorrhaphy + heterologous fibrin sealant + hESC off (N + F + T), and neurorrhaphy + heterologous fibrin sealant + hESC on via doxycycline (N + F + D + T). We evaluated the recovery rate using Catwalk and von Frey functional recovery tests, as well as immunohistochemistry analysis. Results The experiments indicated that sensory function improved when transgenic hESCs were used. The regeneration of sensory fibers indeed led to increased reflexes, upon stimulation of the paw ipsilateral to the lesion, as seen by von-Frey evaluation, which was supported by immunohistochemistry. Conclusions Overall, the present data demonstrated that transgenic embryonic stem cells, engineered to overexpress FGF-2 in an inducible fashion, could be employed to support regeneration aiming at the recovery of both motor and sensory functions.

Xavier Valentini, Pauline Deneufbourg, Paula Paci et al.

Nowadays, nanoparticles (NPs) of titanium dioxide (TiO2) are abundantly produced. TiO2 NPs are present in various food products, in paints, cosmetics, sunscreens and toothpastes. However, the toxicity of TiO2 NPs on the central nervous system has been poorly investigated until now. The aim of this study was to evaluate the toxicity of TiO2 NPs on the central nervous system in vitro and in vivo. In cell cultures derived from embryonic cortical brain of rats, a significant decrease in neuroblasts was observed after 24 to 96 h of incubation with TiO2 NPs (5 to 20 μg/ml). This phenomenon resulted from an inhibition of neuroblast proliferation and a concomitant increase in apoptosis. In the same time, a gliosis, characterized by an increase in proliferation of astrocytes and the hypertrophy of microglial cells, occurred. The phagocytosis of TiO2 NPs by microgliocytes was also observed. In vivo, after intraperitoneal injection, the TiO2 NPs reached the brain through the blood brain barrier and the nanoparticles promoted various histological injuries such as cellular lysis, neuronal apoptosis, and inflammation. A reduction of astrocyte population was observed in some brain area such as plexiform zone, cerebellum and subependymal area. An oxidative stress was also detected by immunohistochemistry in neurons of hippocampus, cerebellum and in subependymal area. In conclusion, our study demonstrated clearly the toxic impact of TiO2 NPs on rat brain and neuronal cells and pointed about not yet referenced toxicity impacts of TiO2 such as the reduction of neuroblast proliferation both in vitro and in vivo. Keywords: Nanoparticles, Brain, Cell culture, Oxidative stress, Proliferation

H. K. L. Johansson, J. S. Hansen, B. Elfving et al.

Abstract Background The use of multiwalled carbon nanotubes (MWCNT) is increasing due to a growing use in a variety of products across several industries. Thus, occupational exposure is also of increasing concern, particularly since airway exposure to MWCNTs can induce sustained pulmonary acute phase response and inflammation in experimental animals, which may affect female reproduction. This proof-of-principle study therefore aimed to investigate if lung exposure by intratracheal instillation of the MWCNT NM-400 would affect the estrous cycle and reproductive function in female mice. Results Estrous cycle regularity was investigated by comparing vaginal smears before and after exposure to 67 μg of NM-400, whereas reproductive function was analyzed by measuring time to delivery of litters after instillation of 2, 18 or 67 μg of NM-400. Compared to normal estrous cycling determined prior to exposure, exposure to MWCNT significantly prolonged the estrous cycle during which exposure took place, but significantly shortened the estrous cycle immediately after the exposed cycle. No consistent effects were seen on time to delivery of litter or other gestational or litter parameters, such as litter size, sex ratio, implantations and implantation loss. Conclusion Lung exposure to MWCNT interfered with estrous cycling. Effects caused by MWCNTs depended on the time of exposure: the estrous stage was particularly sensitive to exposure, as animals exposed during this stage showed a higher incidence of irregular cycling after exposure. Our data indicates that MWCNT exposure may interfere with events leading to ovulation.

Bhupander Kumar, Satish Kumar Singh, Meenu Mishra et al.

Polychlorinated biphenyls (PCBs), hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) are toxic, persistent and bioaccumulative long-range atmospheric transport pollutants. These are transported worldwide affecting remote regions far from their original sources, and can transfer into food webs with a wide range of acute and chronic health effects. India ratified the Stockholm Convention with the intention of reducing and eliminating persistent organic pollutants (POPs), and encouraged the support of research on POPs. Despite the ban and restriction on the use of these chemicals in India, their contamination of air, water, sediment, biota and humans has been reported. In this study, surface water samples were collected during January 2012 from the Yamuna River in Delhi, India, and analyzed for PCBs and organochlorine pesticides (OCPs). The concentrations of &Sigma;PCBs and &Sigma;OCPs ranged between 2-779 ng L^&ndash;1 and from less than 0.1 to 618 ng L^&ndash;1 (mean 99&plusmn;38 ng L^&ndash;1 and 221&plusmn;50 ng L^&ndash;1, respectively). The PCB homolog was dominated by 3-4 chlorinated biphenyls. In calculating the toxicity equivalent of dioxin-like PCBs (dl-PCBs)using World Health Organization toxic equivalency factors, dl-PCBs accounted for 10% of a total of 27 PCBs. The concentration of &Sigma;HCH ranged between less than 0.1 and 285 ng L^&ndash;1 (mean 151&plusmn;32 ng L^&ndash;1). However, &Sigma;DDTs concentrations varied between less than 0.1 and 354 ng L^&ndash;1 (mean 83&plusmn;26 ng L^&ndash;1). The concentrations were lower than the US guideline values; however, levels of lindane exceeded those recommended in guidelines. Further in-depth study is proposed to determine the bioaccumulation of these pollutants through aquatic biota to assess the risk of contaminants to human health.

Prianka Mukhopadhyay*, Gautam Kr. Joardar, Kanad Bag, Amrita Samanta, Sonali Sain and Sesadri Koley

Background: Hospital canteens cater to a large population group and personal hygiene and food safety practices of food handlers assume immense importance to prevent food borne disease outbreaks. Objectives: To assess the self-reported behaviour of food handlers on personal hygiene and food safety practices and to find out their morbidity profile. Methods: An observational study was conducted by interviewing 67 consenting food handlers working in different eateries inside a hospital campus, using a pretested, predesigned schedule. Results: Majority (46.3%) of food handlers were educated upto primary level. Only 14.9% foodhandlers received preplacement training and 10.5%, preplacement medical checkup. Though practices of hand washing after going to toilet (95.5%) and before preparing food (79.1%) was reported to be quite high but for most other practices, hygiene was found to be low. Cuts/injuries on hands was reported as the most common morbidity in 44.8% but 11.9% continued work without any treatment. Conclusion: Preplacement training and in-service education on personal / food hygiene should be provided to all food handlers. Periodic medical checkups and routine sanitary inspection can improve their adherence to personal hygiene and food safety practices and prevent outbreak of food borne illnesses

M Moarefian, M Barzegar, M Sattari et al.

Background: Natural antioxidants with plant origin are incorporated to foods in the forms of essential oils or extracts. They can retard lipid oxidation and control spoilage bacteria in foodstuffs (e.g. meat products). Objective: This work was aimed to evaluate the effect of nitrite partial replacement with Mentha piperita essential oil (MPEO) on oxidative, microbial and sensory properties of cooked sausage. Methods: GC/MS was used for the identification of essential oil components. Nitrite content (120 ppm) was reduced and replaced with 20, 40 and 60 ppm of MPEO. The effect of MPEO on product rancidity was assessed by peroxide and TBARS values in sausage samples. Antimicrobial properties of the essential oil were evaluated by MICs and MBCs determination against Escherichia coli and Clostridium perfringens by microdilution method. Also, the effect of this replacement on the product color stability was evaluated by determination of L*, a* and b* values, Hue angle, and E (2-30). Result: Results indicated that peroxide and TBARS values of sample with 20 ppm of MPEO were significantly lower than samples with 40 and 60 ppm of MPEO and control, at the end of storage period. With respect to color parameters, hue angle of the sample with 60 ppm of MPEO was significantly higher than samples with lower essential oil levels and control after 30 days of storage. Moreover, total color difference of sample with 60 ppm of MPEO was lower than other samples and control (p<0.05). Antimicrobial activity of MPEO against Escherichia coli determined as MICs and MBCs were 0.226 and 0.453 mg/ml, respectively. These values turned out as 0.453 and 0.906 mg/ml against Clostridium perfringens. Conclusion: all samples with different essential oil levels were acceptable after 30 days of storage according to PV and TBARS thresholds determined in literature. Replacement of 50 % of nitrite with MPEO is a reasonable approach in order to put down harmful effects of nitrite in sausage and to enhance functionality of the product.

Xie Shuyu, Wang Fenghua, Wang Yan et al.

<p>Abstract</p> <p>Background</p> <p>Our previous studies demonstrated that tilmicosin-loaded hydrogenated castor oil solid lipid nanoparticles (Til-HCO-SLN) are a promising formulation for enhanced pharmacological activity and therapeutic efficacy in veterinary use. The purpose of this work was to evaluate the acute toxicity of Til-HCO-SLN.</p> <p>Methods</p> <p>Two nanoparticle doses were used for the study in ICR mice. The low dose (766 mg/kg.bw) with tilmicosin 7.5 times of the clinic dosage and below the median lethal dose (LD₅₀) was subcutaneously administered twice on the first and 7th day. The single high dose (5 g/kg.bw) was the practical upper limit in an acute toxicity study and was administered subcutaneously on the first day. Blank HCO-SLN, native tilmicosin, and saline solution were included as controls. After medication, animals were monitored over 14 days, and then necropsied. Signs of toxicity were evaluated via mortality, symptoms of treatment effect, gross and microscopic pathology, and hematologic and biochemical parameters.</p> <p>Results</p> <p>After administration of native tilmicosin, all mice died within 2 h in the high dose group, in the low dose group 3 died after the first and 2 died after the second injections. The surviving mice in the tilmicosin low dose group showed hypoactivity, accelerated breath, gloomy spirit and lethargy. In contrast, all mice in Til-HCO-SLN and blank HCO-SLN groups survived at both low and high doses. The high nanoparticle dose induced transient clinical symptoms of treatment effect such as transient reversible action retardation, anorexy and gloomy spirit, increased spleen and liver coefficients and decreased heart coefficients, microscopic pathological changes of liver, spleen and heart, and minor changes in hematologic and biochemical parameters, but no adverse effects were observed in the nanoparticle low dose group.</p> <p>Conclusions</p> <p>The results revealed that the LD₅₀of Til-HCO-SLN and blank HCO-SLN exceeded 5 g/kg.bw and thus the nanoparticles are considered low toxic according to the toxicity categories of chemicals. Moreover, HCO-SLN significantly decreased the toxicity of tilmicosin. Normal clinic dosage of Til-HCO-SLN is safe as evaluated by acute toxicity.</p>

B. Al, Pınar Yarbil, M. Doǧan et al.

B. Fertel, Lewis S. Nelson, D. Goldfarb