Impairment of postnatal epididymal development and immune microenvironment following administration of low doses of malathion during juvenile and peripubertal periods of rats.

Malathion is an organophosphate pesticide widely used for agricultural crops and for vector control of Aedes aegypti. Humans are exposed to this environmental contaminant by ingesting contaminated food. The juvenile and peripubertal periods are critical for the postnatal development of the epididymis and are when animals are most vulnerable to toxic agents. Since juveniles and adolescents are developing under exposure to the insecticide malathion, the aim of the present study was to evaluate the effects of exposure to low doses of malathion on postnatal epididymal development in rats. Male Wistar rats were exposed to malathion daily via gavage at doses of 10 mg kg-1 (M10 group) or 50 mg kg-1 (M50 group) for 40 days (postnatal days (PNDs) 25-65). The control group received the vehicle (0.9% saline) under the same conditions. On PND 40, the epididymides were removed, weighed and used for histological analysis and determination of the inflammatory profile and sperm count. Sperm from the vas deferens were subjected to sperm motility analysis. The M50 group showed tissue remodelling in the caput and cauda epididymides and increased neutrophil and macrophage migration in the caput epididymis. The M10 group showed decreased motile spermatozoa and IL-6 levels in the caput epididymis. Both doses decreased the IL-1ß level and altered the morphology of the same region. These results show that malathion exposure may impair postnatal epididymal development. Furthermore, alterations of the immune system in the epididymal environment are presented as new findings regarding the action of malathion on the epididymis.

Lipoxin A4 inhibits UV radiation-induced skin inflammation and oxidative stress in mice.

BACKGROUND: Lipoxin A4 (LXA4) is a metabolic product of arachidonic acid. Despite potent anti-inflammatory and pro-resolution activities, it remains to be determined if LXA4 has effect on ultraviolet (UV) radiation-induced skin inflammation. OBJECTIVE: To investigate the effects of systemic administration with LXA4 on UV radiation-induced inflammation and oxidative damage in the skin of mice. METHODS: Varied parameters of inflammation and oxidative stress in the skin of mice were evaluated after UV radiation (4.14 J/cm2). RESULTS: Pretreatment with LXA4 significantly inhibited UV radiation-induced skin edema and myeloperoxidase activity. LXA4 efficacy was enhanced by increasing the time of pre-treatment to up to 72 h. LXA4 reduced UV radiation-induced skin edema, neutrophil recruitment (myeloperoxidase activity and LysM-eGFP+ cells), MMP-9 activity, deposition of collagen fibers, epidermal thickness, sunburn cell counts, and production of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6 and IL-33). Depending on the time point, LXA4 increased the levels of anti-inflammatory cytokines (TGF-ß and IL-10). LXA4 significantly attenuated UV radiation-induced oxidative damage returning the oxidative status to baseline levels in parameters such as ferric reducing ability, scavenging of free radicals, GSH levels, catalase activity and superoxide anion production. LXA4 also reduced UV radiation-induced gp91phox [nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2) subunit] mRNA expression and enhanced nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream target enzyme nicotinamide adenine dinucleotide (phosphate) quinone oxidoreductase (Nqo1) mRNA expression. CONCLUSION: LXA4 inhibited UV radiation-induced skin inflammation by diminishing pro-inflammatory cytokine production and oxidative stress as well as inducing anti-inflammatory cytokines and Nrf2.

Mice lacking interleukin-18 gene display behavioral changes in animal models of psychiatric disorders: Possible involvement of immunological mechanisms.

Preclinical and clinical evidence suggests pro-inflammatory cytokines might play an important role in the neurobiology of schizophrenia and stress-related psychiatric disorders. Interleukin-18 (IL-18) is a member of the IL-1 family of cytokines and it is widely expressed in brain regions involved in emotional regulation. Since IL-18 involvement in the neurobiology of mental illnesses, including schizophrenia, remains unknown, this work aimed at investigating the behavior of IL-18 null mice (KO) in different preclinical models: 1. the prepulse inhibition test (PPI), which provides an operational measure of sensorimotor gating and schizophrenic-like phenotypes; 2. amphetamine-induced hyperlocomotion, a model predictive of antipsychotic activity; 3. resident-intruder test, a model predictive of aggressive behavior. Furthermore, the animals were submitted to models used to assess depressive- and anxiety-like behavior. IL-18KO mice showed impaired baseline PPI response, which was attenuated by d-amphetamine at a dose that did not modify PPI response in wild-type (WT) mice, suggesting a hypodopaminergic prefrontal cortex function in those mice. d-Amphetamine, however, induced hyperlocomotion in IL-18KO mice compared to their WT counterparts, suggesting hyperdopaminergic activity in the midbrain. Moreover, IL-18KO mice presented increased basal levels of IL-1ß levels in the hippocampus and TNF-α in the prefrontal cortex, suggesting an overcompensation of IL-18 absence by increased levels of other proinflammatory cytokines. Although no alteration was observed in the forced swimming or in the elevated plus maze tests in naïve IL-18KO mice, these mice presented anxiogenic-like behavior after exposure to repeated forced swimming stress. In conclusion, deletion of the IL-18 gene resembled features similar to symptoms observed in schizophrenia (positive and cognitive symptoms, aggressive behavior), in addition to increased susceptibility to stress. The IL-18KO model, therefore, could provide new insights into how changes in brain immunological homeostasis induce behavioral changes related to psychiatric disorders, such as schizophrenia.

White luminescence achieved by a multiple thermochromic emission in a hybrid organic-inorganic compound based on 3-picolylamine and copper(i) iodide.

Three copper(i) complexes have been obtained by the reaction of CuI with 3-picolylamine in acetonitrile solution and characterized by X-ray powder diffraction, both from synchrotron and laboratory radiation. Photophysical investigations in the solid state revealed highly efficient thermally-activated delayed fluorescence (TADF) with photoluminescence quantum yields (PLQYs) up to 18%. Notably, the complex [Cu2I2(3pica)]∞ displays a strong luminescence thermochromism due to the presence of both 1,3(X + M)LCT excited states and a lower-lying cluster-centered (3CC) one, leading to multiple emission at room temperature; as a result, a white luminescence is achieved with a PLQY of 4.5%.

Microbiological quality of complementary foods and its association with diarrhoeal morbidity and nutritional status of Bangladeshi children.

BACKGROUND/OBJECTIVES: To examine the bacteriological quality of complementary foods (CF) and to correlate the results with diarrhoeal morbidity and nutritional status of Bangladeshi children aged 6-24 months. SUBJECTS/METHODS: A total of 212 CF samples were tested, of which 72 were collected immediately before the first time of feeding (≤ 1 h of food preparation) and 140 were collected at second/third time of feeding from 140 households located in urban and rural areas of Bangladesh. Anthropometry, food frequency data and demographic information of the children were collected. RESULTS: Of the first time feeding samples, 3% from each of urban and rural areas were found to be contaminated with faecal coliforms (FC) at ≥ 100 CFU/g. E. coli was isolated from 11% and 6% of samples, and B. cereus from 8% and 6% of samples from urban and rural areas, respectively. In contrast, 33% of the second/third time feeding samples from urban areas and 19% from rural areas were contaminated with FC at ≥ 100 CFU/g (P<0.05). E. coli was isolated from 40% and 39% of samples, and B. cereus from 33% and 26% of samples from urban and rural areas, respectively. Significantly high numbers of wasted rural children had CF with a high aerobic plate count, which was also significantly associated with diarrhoeal morbidity in children. CONCLUSIONS: Around 40% of CF samples were contaminated with E. coli, which was mainly attributable to food preparation practices. Consumption of contaminated CF appeared to be associated with a higher frequency of diarrhoea and malnutrition in children.

Photophysics of an electrophosphorescent platinum (II) porphyrin in solid films.

We examine electronic processes in platinum (II) octaethyl porphyrin (PtOEP) embedded in an organic solid state matrix and in the form of vacuum-evaporated neat films in conjunction with potential applications of this compound to organic photovoltaic and electrophosphorescent devices. Absorption, photoexcitation, and luminescence spectra indicate the excitonic dimers to be dominant excited states, and their dissociation underlies the charge photogeneration process. Different charge separation distance (1.5 nm and 2.6 nm) in opposite charge carrier pairs preceding dissociation can be distinguished based on the fit of the three-dimensional Onsager theory of geminate recombination to electromodulated luminescence and photoconduction measurements. The near-positive electrode concentrated triplet dimer excitons, produced by strongly 370 nm absorbed light in neat PtOEP films, are efficiently quenched by electron transfer to the metal (Al), generating the positive charge with an efficiency eta+ exceeding 0.15 at high electric fields and dominating the measured photocurrent. Their dissociation efficiency in the bulk, eta- (negatively biased illuminated electrode), is more than one order of magnitude lower than eta+. The dissociation of singlet dimer states dominates the bulk photogeneration process induced by the weakly-absorbed light at 450 nm, with comparable eta+ and eta-. The "hot excited state" underlying the temperature-increasing emission at 540 nm has been attributed to the upper excitonic component Q+ of the first absorption band Q consistent with the exciton concept applied successfully to the interpretation of all dimer-underlain spectroscopic features of PtOEP samples studied.