Environmental factors during fetal development can induce a permanent epigenetic change in the germ line (sperm) that then transmits epigenetic transgenerational inheritance of adult-onset disease in ...the absence of any subsequent exposure. The epigenetic transgenerational actions of various environmental compounds and relevant mixtures were investigated with the use of a pesticide mixture (permethrin and insect repellant DEET), a plastic mixture (bisphenol A and phthalates), dioxin (TCDD) and a hydrocarbon mixture (jet fuel, JP8). After transient exposure of F0 gestating female rats during the period of embryonic gonadal sex determination, the subsequent F1-F3 generations were obtained in the absence of any environmental exposure. The effects on the F1, F2 and F3 generations pubertal onset and gonadal function were assessed. The plastics, dioxin and jet fuel were found to promote early-onset female puberty transgenerationally (F3 generation). Spermatogenic cell apoptosis was affected transgenerationally. Ovarian primordial follicle pool size was significantly decreased with all treatments transgenerationally. Differential DNA methylation of the F3 generation sperm promoter epigenome was examined. Differential DNA methylation regions (DMR) were identified in the sperm of all exposure lineage males and found to be consistent within a specific exposure lineage, but different between the exposures. Several genomic features of the DMR, such as low density CpG content, were identified. Exposure-specific epigenetic biomarkers were identified that may allow for the assessment of ancestral environmental exposures associated with adult onset disease.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Unlike their more common linear counterparts, cyclic polymers have a ring-like structure and a lack of chain ends. Because of their topology, cyclic polymers exhibit a unique set of properties when ...compared with linear or branched macromolecules. For example, cyclic homopolymers exhibit a reduced hydrodynamic volume and a slower degradation profile compared with their linear analogues. Cyclic block copolymers self-assemble into compact nanostructures, as illustrated by their reduced domain spacing when cast into thin films and their reduced micellar size in solution. Although methods for preparing well-defined cyclic polymers have only been available since 1980, the extensive utilization of the cyclic topology in nature highlights the vital role that a cyclic architecture can play in imparting valuable physical properties, such as increased chemical stability or propensity towards self-assembly. This Review describes the major developments in the synthesis of cyclic polymers and provides an overview of their fundamental physical properties. In this context, preliminary studies exploring potential applications will be critically assessed and the remaining challenges for the field delineated.
A number of environmental factors (e.g. toxicants) have been shown to promote the epigenetic transgenerational inheritance of disease and phenotypic variation. Transgenerational inheritance requires ...the germline transmission of altered epigenetic information between generations in the absence of direct environmental exposures. The primary periods for epigenetic programming of the germ line are those associated with primordial germ cell development and subsequent fetal germline development. The current study examined the actions of an agricultural fungicide vinclozolin on gestating female (F0 generation) progeny in regards to the primordial germ cell (PGC) epigenetic reprogramming of the F3 generation (i.e. great-grandchildren). The F3 generation germline transcriptome and epigenome (DNA methylation) were altered transgenerationally. Interestingly, disruptions in DNA methylation patterns and altered transcriptomes were distinct between germ cells at the onset of gonadal sex determination at embryonic day 13 (E13) and after cord formation in the testis at embryonic day 16 (E16). A larger number of DNA methylation abnormalities (epimutations) and transcriptional alterations were observed in the E13 germ cells than in the E16 germ cells. These observations indicate that altered transgenerational epigenetic reprogramming and function of the male germline is a component of vinclozolin induced epigenetic transgenerational inheritance of disease. Insights into the molecular control of germline transmitted epigenetic inheritance are provided.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Bacterial biofilm plays a pivotal role in bioremediation of heavy metals from wastewaters. In this study, we isolated and identified different biofilm producing bacteria from wastewaters. We also ...characterized the biofilm matrix i.e., extracellular polymeric substances (EPS) produced by different bacteria. Out of 40 isolates from different wastewaters, only 11 (27.5%) isolates (static condition at 28°C) and 9 (22.5%) isolates (agitate and static conditions at 28 and 37°C) produced air-liquid (AL) and solid-air-liquid (SAL) biofilms, respectively, only on salt-optimized broth plus 2% glycerol (SOBG) but not in other media tested. Biomass biofilms and bacteria coupled with AL biofilms were significantly (
≤ 0.001) varied in these isolates.
(isolate ENSD101 and ENST501),
(ENSD102),
(ENSH201),
(ENSH202 and ENSG304), uncultured
sp. (ENSG301 and ENSG305),
(ENSG302),
(ENSG303), and
(ENSW401) were identified based on 16S rRNA gene sequencing. Scanning electron microscope (SEM) images revealed that biofilm matrix produced by
ENSD102, uncultured
sp. ENSG301,
ENSG302, and
ENSG303 are highly fibrous, compact, and nicely interlinked as compared to the biofilm developed by
ENSH201 and
ENSW401. X-ray diffraction (XRD) results indicated that biofilm matrix produced by
ENSD102, uncultured
sp. ENSG301, and
ENSG302 are non-crystalline amorphous nature. Fourier transform infrared (FTIR) spectroscopy showed that proteins and polysaccharides are the main components of the biofilms. Congo red binding results suggested that all these bacteria produced proteinaceous curli fimbriae and cellulose-rich polysaccharide. Production of cellulose was also confirmed by Calcofluor binding- and spectrophotometric assays.
ENSD102,
sp. ENSG301, and
ENSG302 were tested for their abilities to form the biofilms exposure to 0 to 2000 mg/L of copper sulfate (for Cu), zinc sulfate (for Zn), lead nitrate (for Pb), nickel chloride (for Ni), and potassium dichromate (for Cr), several concentrations of these metals activated the biofilm formation. The polysaccharides is known to sequester the heavy metals thus, these bacteria might be applied to remove the heavy metals from wastewater.
Environmental compounds including fungicides, plastics, pesticides, dioxin and hydrocarbons can promote the epigenetic transgenerational inheritance of adult-onset disease in future generation ...progeny following ancestral exposure during the critical period of fetal gonadal sex determination. This study examined the actions of the pesticide methoxychlor to promote the epigenetic transgenerational inheritance of adult-onset disease and associated differential DNA methylation regions (i.e. epimutations) in sperm. Gestating F0 generation female rats were transiently exposed to methoxychlor during fetal gonadal development (gestation days 8 to 14) and then adult-onset disease was evaluated in adult F1 and F3 (great-grand offspring) generation progeny for control (vehicle exposed) and methoxychlor lineage offspring. There were increases in the incidence of kidney disease, ovary disease, and obesity in the methoxychlor lineage animals. In females and males the incidence of disease increased in both the F1 and the F3 generations and the incidence of multiple disease increased in the F3 generation. There was increased disease incidence in F4 generation reverse outcross (female) offspring indicating disease transmission was primarily transmitted through the female germline. Analysis of the F3 generation sperm epigenome of the methoxychlor lineage males identified differentially DNA methylated regions (DMR) termed epimutations in a genome-wide gene promoters analysis. These epimutations were found to be methoxychlor exposure specific in comparison with other exposure specific sperm epimutation signatures. Observations indicate that the pesticide methoxychlor has the potential to promote the epigenetic transgenerational inheritance of disease and the sperm epimutations appear to provide exposure specific epigenetic biomarkers for transgenerational disease and ancestral environmental exposures.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Evidence suggests first episode psychosis (FEP) is associated with suicide, and the influence of depression on suicidal behaviour in cross sectional studies is clear. However the influence of ...depression during FEP on longer-term mortality is not certain. Existing evidence was synthesised to understand the influence of depressive symptoms during FEP on subsequent suicidal behaviour.
Medline, Embase, PsycINFO, Cochrane Library, Web of Science, OpenGrey, and NICE Evidence were searched from inception to Jan 25, 2017. Longitudinal observational studies assessing the relationship between depressive symptoms during FEP with a measure of s at a specified follow-up time were included. Summary estimates were extracted. The Downs and Black Instrument was used to appraise study quality. Odds ratio (OR) of suicidal behaviour were calculated using random effects meta-analyses. The study protocol was registered with PROSPERO (CRD42017055881).
Of 4210 articles found, 23 fulfilled eligibility criteria. 13 were included in meta-analysis (n=3002). 428 participants demonstrated suicidal behaviour in the study periods. Odds of suicidal behaviour during follow-up were significantly higher among patients with depressive symptoms during FEP compared to those without (OR=1.59, 95% CI 1.14–2.21; I2=50.0%, p=0.02). Meta-regression demonstrated no evidence of influence of length of follow-up on results.
Depressive symptoms during FEP are associated with increased longer-term risk of suicidal behaviour. This association should be acknowledged during early management planning. Large-scale clinical trials are needed to identify efficacious management of depression during FEP.
Although child physical abuse (CPA) is considered as a major global public health problem, it has not yet been recognized as such in Bangladesh. Very few studies have assessed the prevalence and ...victims' characteristics of multiple forms of CPA.
This population-based study assessed the prevalence of CPA committed by adults in a rural area of Bangladesh and examined its association with demographic and socio-contextual factors.
Data were obtained using ISPCAN Child Abuse Screening Tool for Children (ICAST-C) in a random sample of 1416 children (49% girls, 51% boys) aged 11 to 17 years by face-to-face interviews during March-April 2017. The response rate was 91.5%. To estimate predictors of CPA, physical abuse was categorized into frequent and less frequent groups.
The prevalence of at least one form (≥ 1), two forms (≥2) and three or more forms (≥ 3) of CPA were estimated approximately to 99%, 95% and 83% in their lifetime and 93%, 79%, and 57% in the past year respectively. Hitting (except on buttocks), standing/kneeling and slapping were the most common physical abuse whereas given drugs or alcohol, pinched, burned or scalded, beaten-up and locked up were less reported. Female children were faced severe forms of CPA more than that of males. Male children, younger age groups, witnessing adults using weapons at home, bullied by siblings and low level of maternal education were found to be significant risk factors for both ≥ 1 form and ≥ 2 forms of frequent CPA whereas adding also adult shouting in a frightening way was found as a significant risk factor for ≥ 2 forms of frequent CPA.
Self-reported prevalence of CPA is extremely common in the Bangladeshi rural society. The prevalence was associated with demographic and socio-contextual characteristics of the children such as being younger, witnessing domestic violence and maternal low education. The findings provide evidence to support parents and policy-makers to take effective measures to implement policy and programme on alternative up-bringing methods and creating awareness of negative effects of CM which in turn help Bangladesh to line up with UN Convention on the Rights of the Child, which the country signed in 1990.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Biomass burning can significantly impact the chemical and optical properties of carbonaceous aerosols. Here, the biomass burning impacts were studied during wintertime in a megacity of Nanjing, ...eastern China. The high abundance of biomass burning tracers such as levoglucosan (lev), mannosan (man), galactosan (gal) and non-sea-salt potassium (nss-K+) was found during the studied period with the concentration ranges of 22.4–1476 ng m−3, 2.1–56.2 ng m−3, 1.4–32.2 ng m−3 and 0.2–3.8 µg m−3, respectively. The significant contribution of biomass burning to water-soluble organic carbon (WSOC; 22.3±9.9 %) and organic carbon (OC; 20.9±9.3 %) was observed in this study. Backward air mass origin analysis, potential emission sensitivity of elemental carbon (EC) and MODIS fire spot information indicated that the elevations of the carbonaceous aerosols were due to the transported biomass-burning aerosols from southeastern China. The characteristic mass ratio maps of lev∕man and lev∕nss-K+ suggested that the biomass fuels were mainly crop residuals. Furthermore, the strong correlation (p < 0.01) between biomass burning tracers (such as lev) and light absorption coefficient (babs) for water-soluble brown carbon (BrC) revealed that biomass burning emissions played a significant role in the light-absorption properties of carbonaceous aerosols. The solar energy absorption due to water-soluble brown carbon and EC was estimated by a calculation based on measured light-absorbing parameters and a simulation based on a radiative transfer model (RRTMG_SW). The solar energy absorption of water-soluble BrC in short wavelengths (300–400 nm) was 0.8±0.4 (0.2–2.3) W m−2 (figures in parentheses represent the variation range of each parameter) from the calculation and 1.2±0.5 (0.3–1.9) W m−2 from the RRTMG_SW model. The absorption capacity of water-soluble BrC accounted for about 20 %–30 % of the total absorption of EC aerosols. The solar energy absorption of water-soluble BrC due to biomass burning was estimated as 0.2±0.1 (0.0–0.9) W m−2, considering the biomass burning contribution to carbonaceous aerosols. Potential source contribution function model simulations showed that the solar energy absorption induced by water-soluble BrC and EC aerosols was mostly due to the regionally transported carbonaceous aerosols from source regions such as southeastern China. Our results illustrate the importance of the absorbing water-soluble brown carbon aerosols in trapping additional solar energy in the low-level atmosphere, heating the surface and inhibiting the energy from escaping the atmosphere.
•La and Ce doped ZnO have been synthesized using sol–gel method.•The characterization of La and Ce doped ZnO showed uniform morphology having wurtzite phase and good structural stability.•ZnO ...particle with dopant concentration of 0.9% (La) and 2.0% (Ce) showed the highest photocatalytic activity as compared to the other dopant concentrations for the degradation of all the dyes under investigation.
Nanocrystalline materials of pure and doped ZnO with La/Ce metals have been successfully synthesized using sol gel method. The prepared materials were characterized by standard analytical techniques, i.e., XRD, SEM, EDX, UV–vis Spectroscopy and FTIR. The (XRD) analysis showed that the obtained particles are present in partial crystalline nature with Hexagonal wurtzite phase and exhibit no other impurity phase. The EDX and (SEM) images depicted that La and Ce metals has been successfully loaded on the surface of ZnO. FTIR of La doped ZnO showed an additional absorption band at 910cm−1, characteristic of La–O absorption band indicating the incorporation of dopant into the ZnO lattice in addition to a broad and strong absorption band in the region of 410–580cm−1 due to Zn–O stretching. The UV–vis absorption spectra of synthesized particles indicate that the doping of La and Ce metals into the ZnO lattice shift the absorption band towards the visible region. Thermal analysis measurement of the synthesized sample showed that the thermal stability of pure ZnO is decreased due to increase in dopant concentration. The photocatalytic activity of the synthesized particles was studied by measuring the change in concentration of three different chromophoric dyes as a function of irradiation time. The photocatalytic activity of doped ZnO was found to increase with increase in dopant concentration of Ce from 0 to 2.0% and La from 0 to 0.9%. A further increase in dopant concentration led to decrease in the degradation rate of dyes.
PM2.5 aerosols were collected at Fairbanks (64.51∘ N and
147.51∘ W) in central Alaska during the summer of 2009 and
analyzed for organic tracer compounds using a gas chromatograph–mass
spectrometer. ...The organic compounds were grouped into 14 classes based
on their functional groups and sources. Concentrations of the total organics
measured ranged from 113 to 1664 ng m−3 (avg 535 ng m−3).
Anhydrosugars (avg 186 ng m−3) and n-alkanoic acids (avg 185 ng m−3) were 2 major classes among the 14 compound classes. The similar
temporal trends and strong positive correlations among anhydrosugars and
n-alkanoic acids demonstrated that biomass burning (BB) is the major source
of organic aerosols (OAs) in central Alaska. The dominance of higher
molecular weight n-alkanoic acids over lower molecular weight homologs and their carbon preference index (5.6–9.8) confirmed that they were mostly
emitted from plant waxes during BB in central Alaska. The mass concentration
ratios of levoglucosan to mannosan denoted that softwood is the main biomass
burned. The rainfall event distinctly enhanced the levels of mannitol and
arabitol due to the growth of fungi and active discharge of fungal spores in
the subarctic region. Molecular compositions of biogenic secondary organic
aerosol (BSOA) tracers inferred that isoprene is a crucial precursor of BSOA
over central Alaska. Our results suggest forest fires and plant emissions to
be the crucial factors controlling the levels and molecular composition of
OAs in central Alaska. We propose that PM2.5 laden with OAs derived in
central Alaska may significantly impact the air quality and climate in
the Arctic via long-range atmospheric transport.
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