Short Period Of Exposure Research Articles

Repeated intratracheal instillation of whole-cigarette smoke condensate to assess lung damage in a rat model.

Cigarette smoke induces an inflammatory response in the lungs by recruiting inflammatory cells, leading to lung diseases such as lung cancer, chronic obstructive pulmonary disease, and pulmonary fibrosis. Existing inhalation exposure methods for assessing the adverse effects of cigarette smoke require expensive equipment and are labor-intensive. Therefore, we attempted to develop a novel method to assess these adverse effects using intratracheal instillation (ITI) of whole cigarette smoke condensate (WCSC). The WCSC (0, 5, 10, or 20 mg/mL) was administered by ITI once daily for 6 or 12 days using an automatic video instillator. Repeated WCSC ITI increased the lung weight, and monocyte chemoattractant protein-1 (MCP-1), neutrophil, and lymphocyte levels within bronchoalveolar lavage fluid compared to the control. In the histopathological analysis of the lung tissue, a mild inflammatory response was observed in the 6 and 12 days 20 mg/mL WCSC exposure groups. The genome-wide RNA-seq expression patterns revealed that inflammatory and immune response-related genes, such as the chemokine signaling pathway, Th1/Th2 cell differentiation, and cytokine-cytokine receptor interaction, were employed following WCSC exposure. In addition, MCP-1 was time-dependent and increased in the 10 mg/mL exposure group compared to the control group. These results suggested that the WCSC might induce the potential pulmonary inflammatory response. Furthermore, we proposed that ITI may be a rapid and effective method of evaluating the adverse effects of WCSC within a short exposure period (less than 2 weeks), and it can be used to evaluate cigarette inhalation toxicity studies as an alternative method.

Obstetric and psychiatric history as predictors for psychosomatic symptoms among Korean perimenopausal women.

Menopause presents various physical and psychological disturbances for women and comes at a high financial cost. Therefore, this study aimed to identify factors influencing menopause symptoms. Data of Korean perimenopausal women aged 40-60 (n=1060; mean age, 46.03±4.08) were collected by a research company. Participants were classified into a "functional" group (n=716) or a "dysfunctional" group (n=344) according to the severity of their perimenopausal psychosomatic symptoms. To investigate the association of obstetric and psychiatric history with membership of the "dysfunctional" group, a hierarchical logistic regression analysis was conducted. The outcomes of all three hierarchical logistic regression models presented significant overall model fit. Among the independent variables, family history of menopausal symptoms, menarcheal age, number of pregnancies, history of postpartum depression, postpartum psychosis, and other psychiatric disorders were positively associated with being in the "dysfunctional" group, whereas age and number of deliveries were negatively associated with being in the "dysfunctional" group. A short reproductive period and short exposure to estrogen due to late menarche and early menopausal transition may be related to severe perimenopausal symptoms. The relationship between the history of postpartum mental illness and severe perimenopausal symptoms may be associated with heightened sensitivity to hormonal triggers when a woman is exposed to fluctuating ovarian sex steroid levels. The relationship between parity or gravidity and the severity of menopausal symptoms in Korean women differed from that in studies conducted in other countries, possibly due to the low birth rate in Korea.

Temperature and photo sensitive PVDF-g-PNIPAAm/BN@PDA-Ag nanocomposite membranes with superior wasterwater separation and light-cleaning capabilities

Traditional water treatment membranes always face the problem of membrane contamination in the practical application. Those contaminants deposited on the membrane surface and inside the membrane pores make the filtration process more difficult. Herein, the temperature and photo sensitive nanocomposite membranes with superior wasterwater separation and light-cleaning capabilities were prepared by a non-solvent induced phase separation method, which combined the thermo-responsive property of poly(N-isopropylacrylamide) (PNIPAAm) grafted polyvinylidene fluoride (PVDF) and the high photothermal conversion character of core–shell structured BN@PDA-Ag nanosheets. The membranes can be heated to high temperature within a short period of light exposure due to the fast photothermal conversion capability of Ag and the excellent thermal conductivity of boron nitride (BN). The increase in temperature led to the contraction of PNIPAAm chains and bigger pore size. The microstructure, filtration, and cleaning performance of the nanocomposite membranes can be controlled by illumination, which allowed PVDF-g-PNIPAAm/BN@PDA-Ag membranes to achieve the effect of first interception and then cleaning. The membranes showed retention rates of 82, 99 and 95 % for BSA, oil–water emulsions and various dyes with flux recovery rates of > 90 % after light cleaning. This work provides a simpler, more efficient membrane cleaning strategy with superior potential for dealing with membrane contamination.

Measurement of Radiation Exposure of Hands and Fingers of Nuclear Medicine Personnel Using Innovative Low-Cost GM Based System

Pocket dosimeters are used commonly in Nuclear Medicine or radiology workers for daily dose measurement or during certain high radiation exposure procedures for short periods of time. These are expensive and have many maintenance costs. It may not be feasible to procure many at a time due to cost restraints. We designed a low cost remote dose monitoring device for measurement of radiation for short periods of time. Measuring device was constructed using micro Geiger Muller Counter. The micro-Geiger Counter with model no SBM21 was connected to high voltage circuit and the output signal was obtained. After this, output signal was sent it to Arduino circuit running custom code ESP8266 and readings was made on the mobile/ laptop application after connecting to Arduino circuit running custom code ESP8266 via internet. Readings were taken for short durations during certain periods. Readings were compared to the standard measuring instrument simultaneously. The tube was connected to their hands for hand exposure with a wire. Readings were recorded in the form of μSv/h or mSv/h. RESULT: Total readings were taken during various occasions while preparing (59) and dispensing (45) radioisotopes. During preparation of radiopharmaceuticals, average readings for 99mTc-Sestamibi[16 SAMPLE] (100mCi to 250mCi), 99mTc-MDP [21SAMPLE] (150-200mCi) and 99mTc-DTPA [22SAMPLES] (10-20mCi) were 1115 μSv/h, 3083 μSv/h and 453 μSv/h respectively. During dispensing of radiopharmaceuticals, average readings of total 15 sample each for 99mTc-Sestamibi (100mCi to 250mCi), 99mTc-MDP (150-200mCi) and 99mTc-DTPA (10-20mCi) were 351μSv/h, 209 μSv/h and 235 μSv/h respectively. It was feasible for the worker to fit the measuring device in their pocket while working. Conclusion: Our pilot study revealed accurate readings >95% of the times for short periods of time. Study designing, standardization of readings with more real time accuracy can make this method more reliable and is a low cost means to monitor short periods of radiation exposure for radiation workers.

Evidence and mineralogical and physico-chemical properties of chernozem and chernozem-like soils in Croatia

The aim was to determine possible local differences between the parent materials of recent leoss-derived soils in eastern Croatia (Dalj, Zmajevac). Furthermore, it highlights the existence of chernozem and chernozem-like soils in Croatia and describes their basic physical, chemical and mineral properties. For this purpose, two soil profiles (P-3 and P-6) south of the Dalj settlement and one soil profile (P-10) near the Zmajevac settlement were excavated. The investigation included a detailed pedological analysis, a modal analysis of the heavy and light mineral fraction and a mineralogical analysis of bulk samples (the < 2 mm fraction) and the fraction < 2 μm. By comparing the obtained results with the criteria of the Croatian Soil Classification and the World Reference Base for Soil Resources, the soil profiles P-3 and P-6 can be defined as Chernozem on Loess or Hortic Calcic chernozem (Epiloamic, Endosiltic, Aric, Humic). The systematic unit for profile P-10 was defined as Rendzina according to the Croatian Soil Classification or Calcic Chernozem (Siltic) according to the WRB. Based on the results of the pedological analysis of the soil profile horizons, a gradual degradation of the chernozem was observed as a result of anthropogenic influence, but also due to recent climate change. The degradation is particularly evident in the form of a reduction in organic matter and the relocation of carbonates from the surface to deeper zones. Due to the increasing degree of weathering caused by recent climate changes, some differences in the mineralogical composition of the studied soils were also observed. The progressive degradation of the chernozem due to the effects of recent weathering processes is indicated mainly by the presence of goethite in the fraction < 2 μm as a weathering product of iron minerals (magnetite, pyroxenes…). Although the parent material of all three profiles is loess sediments, the reason why the soil material of profile P-10 has not developed a chernic horizon is the constant contribution of aeolian material and a short period of exposure to pedogenetic processes.

RNA-seq Analysis Reveals Potential Synergic Effects of Acetate and Cold Exposure on Interscapular Brown Adipose Tissue in Mice.

Brown adipose tissue (BAT) exhibits remarkable morphological and functional plasticity in response to environmental (e.g., cold exposure) and nutrient (e.g., high-fat diet) stimuli. Notably, a number of studies have showed that acetate, the main fermentation product of dietary fiber in gut, profoundly influences the differentiation and activity of BAT. However, the potential synergic or antagonistic effects of acetate and cold exposure on BAT have not been well examined. In the present study, the C57BL/6J mice were treated with acetate at the systemic level before a short period of cold exposure. Physiological parameters including body weight, blood glucose, and Respiratory Exchange Ratio (RER) were monitored, and thermal imaging of body surface temperature was captured. Moreover, the transcriptome profiles of interscapular BAT were also determined and analyzed afterwards. The obtained results showed that acetate treatment prior to cold exposure could alter the gene expression profile, as evidenced by significant differential clusters between the two groups. GO analysis and KEGG analysis further identified differentially expressed genes being mainly enriched for a number of biological terms and pathways related to lipid metabolism and brown adipose activity such as "G-protein-coupled receptor activity", "cAMP metabolic process", "PPAR signaling pathway", and "FoxO signaling pathway". GSEA analysis further suggested that activation status of key pathways including "PPAR signaling pathway" and "TCA cycle" were altered upon acetate treatment. Taken together, our study identified the potential synergistic effect of acetic acid with cold exposure on BAT, which highlighted the positive dietary and therapeutic aspects of acetate.

The immunotoxicity mechanism of NH4Cl exposure to Litopenaeus vannamei based on the cerebral ganglion-eyestalk-haemocytes axis

Ammonia nitrogen, as a water environmental toxin, poses a potential threat to aquatic animals. Although NH4Cl stress is known to cause immunotoxicity, mechanistic pathways linking stress networks in the neuroendocrine system to immunotoxicity remain poorly understood. In this study, firstly, using transcriptome analysis of cerebral ganglion and eyestalk in shrimp, we identified significant changes in genes related to biogenic amines, acetylcholine, crustacean hyperglycemic hormones, and neuropeptide F. Additionally, expression patterns of neuroendocrine factors in different tissues of shrimp were evaluated to explore the sources of these factors. Here, we showed that NH4Cl exposure activates acetylcholine (ACh) neurons in cerebral ganglion of shrimp and dramatically upregulates high affinity choline transporter 1 (ChT1) gene expression. The knockdown of ChT1 gene enhanced the immunity of haemocytes in shrimp compared with saline and GFP dsRNA groups. And after eyestalk ablation, the levels of neuroendocrine factors in the cerebral ganglion and thoracic ganglion were disturbed, and haemocytes parameters induced by NH4Cl were significantly decreased. Combined with different doses of NH4Cl exposure experiments, we demonstrated that: (1) In a short period of NH4Cl exposure, the neuroendocrine factors CRH–ACTH–cortisol and 5-HT–DA in the cerebral ganglion–eyestalk axis of shrimp play a major role in regulating haemocytes immunity; (2) With the prolongation of exposure, the immunotoxicity induced by NH4Cl was mainly due to the release of more ACh in the cerebral ganglion, which promoted the release of NPF in the thoracic ganglion, and CHH and NPF in the eyestalk, as well as weakened the effect of biogenic amines. Subsequently, these neuroendocrine factors regulate immunity through intracellular signaling pathways. Collectively, these results established a new mechanism that NH4Cl might directly regulate haemocytes immunotoxicity through the cerebral ganglion and thoracic ganglion; or through the cerebral ganglion-eyestalk axis or cerebral ganglion-thoracic ganglion axis cause haemocytes immunotoxicity.

Is Occupational Arsenic Exposure a Possible Causative Agent of Breast Cancer for a Young Female Laboratory Technician? A Case-Study

A 28-year-old female laboratory technologist who was exposed to highly concentrated inorganic arsenic for 7 years, 25 hours a week, presented with left breast cancer. When most epidemiologic evidence reported by the IARC supported the relationship between arsenic exposure and cancers of lung, skin and bladder; literature had documented increased risk of breast cancer in specific populational subgroups due to the estrogen-like activity of arsenic. The causal assessment of occupational cancer is challenging due to the lack of relevant data on the worker’s biological monitoring and environmental exposure monitoring data, together with the insufficient genetic composition information like BRCA1 gene. Moreover, the poor work practice and hygiene had made the exposure through dermal contact and digestion possible. The interpretation of work causal relationship while distinct occupational cancer from those of non-occupational must consider individual susceptibility as low-level short-period exposure might increase the risk for certain worker. Therefore, a systematically collected medical surveillance data along with industry hygiene data is highly recommended in order to assist in the refinement of human dose-response relationship of specific work carcinogen

Bio-mediated synthesis of silver nanoparticles using Cotinus coggygria extract and their multifaceted applications

Green synthesis of nanoparticles is comparatively cheaper, eco-friendly, and helps to analyze the anti-microbial nature of the synthesized particles. Through this study, the silver nanoparticles can be synthesized successfully using Cotinus coggygria leaf extract as a reducing agent and a standard solution of AgNO3 as a precursor. A strong peak at 450–480 nm in the UV–Visible spectra revealed that silver nanoparticles (AgNPs) were synthesized using green methods. The synthesized particles were further characterized using XRD, SEM, and EDS. XRD results confirmed that the green synthesized particles are highly crystalline, with an average size of 27nm. From scanning electron microscopy, it is found that the particles are cylindrical in shape. With an inhibitory zone of 7 mm for Staphylococcus aureus and 9 mm for Escherichia coli, respectively, the synthesized silver nanoparticles demonstrated antibacterial activity against these pathogens. The anti-fungal analysis was also performed against Salmonella typhi and found that they can inhibit fungal activity with an inhibition zone of 22 mm. Furthermore, the larvicidal activity of the synthesized nanoparticles was explored following the bioassays performed by following the WHO guidelines. The silver nanoparticles synthesized can be a better option for controlling the growth of mosquitos and has much relevance in public health protection. As the concentration of synthesized AgNPs increases, larval mortality is also higher, even with the shorter exposure period. Our research revealed that Cotinus coggygria leaf extracts have good capping and reducing agents for producing stable AgNPs. Here, a one-step, quick, environmentally friendly, non-toxic approach is used instead of traditional physical and chemical techniques. This study has important medical implications and could pave the way for future research.

Short-term retention of learning after rapid adaptation to native and non-native speecha).

Non-native, accented speech spoken by unfamiliar talkers can be challenging to recognize, but rapid improvements in perception are often observed after a short period of exposure. However, it is not clear whether these improvements are retained over multiple sessions. Stimulus variability facilitates learning for non-native speech, so it is possible it may also induce increased retention of learning for speech produced with an unfamiliar accent. In this paper, we conduct a retrospective analysis of a dataset well suited to examine learning of non-native English speech on both a within-session and across-session basis. During data collection, participants completed a protocol involving recognition of matrix sentences recorded by native and non-native talkers with different first languages. Listeners completed the protocol in a self-paced approach, including 15 blocks of 50 trials over 4-7 days, separated by an average of 1-2 days. Learning was strongest within the first day, and improvements were retained at subsequent test sessions. The pace of learning was faster for stimuli produced by native speakers of English as compared to non-native English speakers.

Perceptual Doping: A Hypothesis on How Early Audiovisual Speech Stimulation Enhances Subsequent Auditory Speech Processing.

Face-to-face communication is one of the most common means of communication in daily life. We benefit from both auditory and visual speech signals that lead to better language understanding. People prefer face-to-face communication when access to auditory speech cues is limited because of background noise in the surrounding environment or in the case of hearing impairment. We demonstrated that an early, short period of exposure to audiovisual speech stimuli facilitates subsequent auditory processing of speech stimuli for correct identification, but early auditory exposure does not. We called this effect "perceptual doping" as an early audiovisual speech stimulation dopes or recalibrates auditory phonological and lexical maps in the mental lexicon in a way that results in better processing of auditory speech signals for correct identification. This short opinion paper provides an overview of perceptual doping and how it differs from similar auditory perceptual aftereffects following exposure to audiovisual speech materials, its underlying cognitive mechanism, and its potential usefulness in the aural rehabilitation of people with hearing difficulties.

The interaction effects of biodegradable microplastics and Cd on Folsomia candida soil collembolan.

In real-field soil conditions, multiple chemicals exposure may be the real scenario for soil biota. The co-occurrence of microplastics (MPs) and cadmium (Cd) is common in soils, which may pose a potential risk to soil ecosystems. Degradable microplastics are producing more MPs, and the potential effects on soil ecosystems are unknown. Therefore, a standard soil animal collembolan Folsomia candida was used to evaluate the single and interaction effects of biodegradable MPs (PLA) and Cd. The results showed that single and co-biodegradable PLA and Cd all had negative influences on the survival, reproduction, and growth of F. candida, and the effects intensified with PLA concentrations. The survival rate, reproduction rate, adult body length, and juvenile body length decreased by 20.0%, 24.2%, 22.9%, and 32.2% at MPs-100 treatment. But combined PLA and Cd alleviated the toxicity of single Cd on F. candida at lower PLA concentrations. The number of juveniles increased by 29.3%, the survival rate increased by 7.52%, the adult body length increased by 11.7%, and the juvenile body length increased by 19.0% at MPs-1 + Cd than single Cd treatment. Biochemical assays on antioxidant enzymes had the same results. Antioxidant enzymes CAT and POD were more sensitive than SOD. CAT and POD activities were induced quickly at shorter exposure periods, and MP treatment thus may be promising biomarkers on soil collembolan for soil MP exposure. PLA is degraded with time in soils; therefore, the long-term effects of co-MPs and Cd in soils are suggested to be further studied.

Thirdhand tobacco smoke exposure increases the genetic background-dependent risk of pan-tumor development in Collaborative Cross mice

Increasing evidence has shown that thirdhand smoke (THS) exposure is likely to induce adverse health effects. An important knowledge gap remains in our understanding of THS exposure related to cancer risk in the human population. Population-based animal models are useful and powerful in investigating the interplay between host genetics and THS exposure on cancer risk. Here, we used the Collaborative Cross (CC) mouse population-based model system, which recapitulates the genetic and phenotypic diversity observed in the human population, to assess cancer risk after a short period of exposure, between 4 and 9 weeks of age. Eight CC strains (CC001, CC019, CC026, CC036, CC037, CC041, CC042 and CC051) were included in our study. We quantified pan-tumor incidence, tumor burden per mouse, organ tumor spectrum and tumor-free survival until 18 months of age. At the population level, we observed a significantly increased pan-tumor incidence and tumor burden per mouse in THS-treated mice as compared to the control (p = 3.04E-06). Lung and liver tissues exhibited the largest risk of undergoing tumorigenesis after THS exposure. Tumor-free survival was significantly reduced in THS-treated mice compared to control (p = 0.044). At the individual strain level, we observed a large variation in tumor incidence across the 8 CC strains. CC036 and CC041 exhibited a significant increase in pan-tumor incidence (p = 0.0084 and p = 0.000066, respectively) after THS exposure compared to control. We conclude that early-life THS exposure increases tumor development in CC mice and that host genetic background plays an important role in individual susceptibility to THS-induced tumorigenesis. Genetic background is an important factor that should be taken into account when determining human cancer risk of THS exposure.

Swimming behaviour as an alternative endpoint to assess differences in abiotic stress sensitivities between strains of Brachionus koreanus (Rotifera: Monogononta)

Brachionus plicatilis is a cosmopolitan rotifer used as a model organism in several research areas and as live food in aquaculture. Being a species complex, responses to stressors vary even among strains of the same species and, thus, the responses of one species are not representative of the whole complex. This study aimed to address the effects of extreme salinity ranges, and different concentrations of hydrogen peroxide, copper, cadmium, and chloramphenicol, in two strains of B. koreanus (MRS10 and IBA3) from B. plicatilis species complex, by assessing effects on their survival and swimming capacity. Neonates (0–4 h old) were exposed to the stressors in 48 well-microplates, for 24 and 6 h, to evaluate lethal and behavioural effects, respectively. Tested conditions of chloramphenicol did not show any effects on rotifers. The behavioural endpoint showed to be particularly sensitive to assess the effects of high salinity, hydrogen peroxide, and copper sulfate, as swimming capacity impairment was observed for both strains in the lowest concentrations used in lethal tests. Overall, results showed that IBA3 was more tolerant to the majority of stressors, comparing to MRS10, which may be due to differences in physiological characteristics, highlighting the importance of performing multiclonal experiments. Also, swimming capacity inhibition proved to be a good alternative to the classical lethality tests, being sensitive to lower concentrations and with shorter exposure periods.

The genetic era of childhood cancer: Identification of high-risk patients and germline sequencing approaches.

Childhood cancer is a leading cause of death by disease in children ages 5-14, for which there are no preventive strategies. Due to early-age of diagnosis and short period of exposure to environmental factors, increasing evidence suggests childhood cancer could have strong association with germline alterations in predisposition cancer genes but, their frequency and distribution are largely unknown. Several efforts have been made to develop tools to identify children with increased risk of cancer who may benefit from genetic testing but their validation and application on a large scale is necessary. Research on genetic bases of childhood cancer is ongoing, in which several approaches for the identification of genetic variants related to cancer predisposition have been used. In this paper, we discuss the updated efforts, strategies, molecular mechanisms and clinical implications for germline predisposition gene alterations and the characterization of risk variants in childhood cancer.

How fish cells responded to zinc challenges: Insights from bioimaging

Zinc ion (Zn) is an essential nutrition element and it is important to understand its regulation and distribution among different cellular organelles. Here, subcellular trafficking of Zn in rabbitfish fin cells was investigated through bioimaging, and the results showed that the toxicity and bioaccumulation of Zn were both dose- and time-dependent. Cytotoxicity of Zn only occurred when the Zn concentration reached 200–250 μM after 3 h of exposure when the cellular quota of Zn:P reached a threshold level around 0.7. Remarkably, the cells were able to maintain homeostasis at a low Zn exposure concentration or within the first 4-h exposure. Zn homeostasis was mainly regulated by the lysosomes which stored Zn within the short exposure period, during which the number and size of lysosomes as well as the lysozyme activity increased in response to incoming Zn. However, with increasing Zn concentration beyond a threshold concentration (> 200 μM) and an exposure time > 3 h, homeostasis was disrupted, leading to an Zn spillover to cytoplasm and other cellular organelles. At the same time, cell viability decreased due to the Zn damage on mitochondria which caused morphological changes (smaller and rounder dots) and over production of reactive oxygen species, indicating the dysfunction of mitochondria. By further purifying the cellular organelles, cell viability was found to be consistent with the mitochondrial Zn amount. This study suggested that the amount of mitochondrial Zn was an excellent predictor of Zn toxicity on fish cells.

Hypergravity Increases Blood-Brain Barrier Permeability to Fluorescent Dextran and Antisense Oligonucleotide in Mice.

The earliest effect of spaceflight is an alteration in vestibular function due to microgravity. Hypergravity exposure induced by centrifugation is also able to provoke motion sickness. The blood-brain barrier (BBB) is the crucial interface between the vascular system and the brain to ensure efficient neuronal activity. We developed experimental protocols of hypergravity on C57Bl/6JRJ mice to induce motion sickness and reveal its effects on the BBB. Mice were centrifuged at 2× g for 24 h. Fluorescent dextrans with different sizes (40, 70 and 150 kDa) and fluorescent antisense oligonucleotides (AS) were injected into mice retro-orbitally. The presence of fluorescent molecules was revealed by epifluorescence and confocal microscopies in brain slices. Gene expression was evaluated by RT-qPCR from brain extracts. Only the 70 kDa dextran and AS were detected in the parenchyma of several brain regions, suggesting an alteration in the BBB. Moreover, Ctnnd1, Gja4 and Actn1 were upregulated, whereas Jup, Tjp2, Gja1, Actn2, Actn4, Cdh2 and Ocln genes were downregulated, specifically suggesting a dysregulation in the tight junctions of endothelial cells forming the BBB. Our results confirm the alteration in the BBB after a short period of hypergravity exposure.

Effect of Water Jet Cavitation Peening on Short-Period Oxidation Behavior of Alloy 600 in PWR Primary Water

Water jet cavitation peening (WJCP) was used to strengthen the surface of nickel-based alloy 600. Residual stress, hardness, surface roughness, microstructure, and short-period oxidation behavior in untreated (UT) and WJCP-treated alloy 600 were characterized. A continuous oxide film was formed on the WJCP-treated surface after a short period of exposure, while it was discontinuous in the UT specimen. The change in oxidation behavior was attributed to the ultrafine grain and dislocation structure resulting from the WJCP treatment.

Antidepressants can induce mutation and enhance persistence toward multiple antibiotics

Antibiotic resistance is an urgent threat to global health. Antidepressants are consumed in large quantities, with a similar pharmaceutical market share (4.8%) to antibiotics (5%). While antibiotics are acknowledged as the major driver of increasing antibiotic resistance, little attention is paid to the contribution of antidepressants in this process. Here, we demonstrate that antidepressants at clinically relevant concentrations induce resistance to multiple antibiotics, even following short periods of exposure. Antibiotic persistence was also enhanced. Phenotypic and genotypic analyses revealed the enhanced production of reactive oxygen species following exposure to antidepressants was directly associated with increased resistance. An enhanced stress signature response and stimulation of efflux pump expression were also associated with increased resistance and persistence. Mathematical modeling also predicted that antidepressants would accelerate the emergence of antibiotic-resistant bacteria, and persister cells would help to maintain the resistance. Overall, our findings highlight the antibiotic resistance risk caused by antidepressants.

A Case of Camphor Toxicity in a Toddler: All on Skin is Not Safe

Paediatric population is very vulnerable to toxicities resulting from exposure to many traditional medicines, which are often used in our culture as treatments for various ailments. People are unaware of the untoward complications arising from the toxicity of these native medicines, especially camphor. Adding to the problem, parents often believe that native medicines, particularly when applied topically, are safe for children. Here, the author reported a previously healthy 2-year-old child who had multiple episodes of seizures after the mother applied topical camphor oil for five days to relieve the child’s symptoms of nasal congestion. While there is no clear data on the concentration and duration of topical camphor exposure that causes toxicity in children, the case report highlighted the possibility that younger children may develop toxicity in a relatively short period of exposure. In this modern era of evidence-based medicine, it is important to raise awareness among the public, especially parents, that not everything applied to the skin is safe for children, as their anatomy differs from that of adults.