Seasonal and nutritional changes in the short form of the leptin receptor expression and VEGF system in the choroid plexus, arcuate nucleus, and anterior pituitary in MTS-leptin and resistin-treated sheep.

The short form of the leptin receptor (LeptRa) plays a key role in the transport of leptin to the central nervous system (CNS). Here, MTS-leptin and recombinant ovine (ro) leptin-mediated expression of LeptRa and VEGFA and VEGFR2 concentration in selected hypothalamic nuclei, choroid plexus (ChP), and anterior pituitary (AP) were analyzed considering the photoperiod and acute-fasting (experiment 1), and nutritional status (experiment 2) of ewes. In experiment 1, 60 sheep were fed normally or fasted for 72 h and received one injection of saline, MTS-leptin, or roleptin 1 h prior to euthanasia. LeptRa mRNA transcript levels and VEGF system protein concentrations were detected in the ARC, ChP predominantly in the SD, and AP for the LD without detection of LeptRa in the POA and VMH/DMH. In experiment 2, an altered diet for 5 months created lean or fat sheep. Twenty sheep were divided into four groups: the lean and fat groups were given saline, while the lean-R and fat-R groups received resistin 1 h prior to euthanasia. Changes in adiposity influenced the lowering effect of resistin on the expression of LeptRa and VEGF system protein concentrations. Overall, both photoperiodic and nutritional signals influence the effects of MTS-leptin/roleptin and resistin-mediated leptin transport to the CNS via LeptRa. Resistin seems to be another adipokine involved in the adaptive/pathological phenomenon of leptin resistance in sheep.

COVID-19 pandemic influence on epilepsy course in pediatric patients.

INTRODUCTION: In 2020, Coronavirus Disease 2019 (COVID-19) was declared as a global pandemic. Self-reported stress, anxiety, and insomnia, which are believed to be common triggers for epilepsy, are more likely to occur. We aimed to establish the influence of COVID-19 pandemic itself on changes in the daily life routine related to pandemic on epilepsy course in pediatric patients. The unique form of clinical care which is telemedicine was also taken into consideration. We wanted to evaluate patients' satisfaction with telemedicine and if changing stationary visits into telemedicine influenced epilepsy course in our patients. METHODS: Patients, who attended developmental neurology outpatient clinic in the period March-December 2020 were collected. As patients were minors, legal guardians were asked to fill out the questionnaire. Patients were divided according to the outcome into three groups: those with a worsened, stable, or improved course of epilepsy during the pandemic. Appropriate statistical tests for two-group and multi-group comparisons have been implemented. Post hoc p values were also calculated. RESULTS: Four hundred and two questionnaires were collected. Most of the patients had a stable course of epilepsy during the pandemic; in 13% of participants an improvement has been observed, worsening of the disease was seen in 16% of patients. Age, sex, type of epilepsy, number of seizure incidents before pandemic, and duration of the disease had no statistically significant connection with changes in the course of the disease. Behavioral changes and altered sleep patterns were found to be more common in the worsened group. Fifty-eight percent of patients were satisfied with telemedicine. Poorer satisfaction was connected with less frequent visits, cancellation of scheduled appointments, and lack of help in case of need in an emergency situation. CONCLUSION: Epilepsy course in pediatric patients seems to be stable during COVID-19 pandemic. Sleep disturbances and changes in a child's behavior may be related to increase in seizure frequency. Telemedicine is an effective tool for supervising children with epilepsy. Patients should be informed about possible ways of getting help in urgent cases.

Effects of Leptin, Growth Hormone and Photoperiod on Pituitary SOCS-3 Expression in Sheep.

This study examined how leptin affects growth hormone (GH) release and investigated the effects of leptin, GH, and day length on the suppressor of cytokine signaling-3 (SOCS-3) mRNA levels in the adenohypophyses of sheep. The study consisted of two experiments. The first experiment was conducted during long (LD) and short (SD) days. Within-season and replicate sheep were centrally infused with Ringer-Locke buffer or leptin three times at 60-min intervals at the beginning of experiments. The second experiment involved adenohypophyses collected from sheep that were euthanized in May or November. Pituitary explants were treated with medium alone (Control) or medium with leptin or GH at different concentrations and incubated for various times. The results of the first experiment indicated GH concentrations were seasonally dependent and that leptin had no effect on GH secretion. The results of the second experiment indicated a stronger influence of leptin on the expression of SOCS-3 during the SD season than the LD season. During SDs, significant effects of both GH doses on SOCS-3 expression were observed. These results indicate a strong association between leptin, GH, and SOCS-3, which may explain the disruption of SOCS-3 leptin and GH signaling and the dominant effect of photoperiod on the above relationships.

Seasonal and Nutritional Fluctuations in the mRNA Levels of the Short Form of the Leptin Receptor (LRa) in the Hypothalamus and Anterior Pituitary in Resistin-Treated Sheep.

The short form of the leptin receptor (LRa) plays a key role in the transport of leptin to the central nervous system (CNS). Here, the resistin (RSTN)-mediated expression of LRa in the preoptic area (POA), ventromedial and dorsomedial nuclei (VMH/DMH),arcuate nucleus (ARC) and the anterior pituitary gland (AP)was analyzed considering the photoperiodic (experiment 1) and nutritional status (experiment 2) of ewes. In experiment 1, 30 sheep were fed normally and received one injection of saline or two doses of RSTN one hour prior to euthanasia. RSTN increased LRa expression mainly in the ARC and AP during long days (LD) and only in the AP during short days (SD). In experiment 2, an altered diet for 5 months created lean or fat sheep. Twenty sheep were divided into four groups: the lean and fat groups were given saline, while the lean-R and fat-R groups received RSTN one hour prior to euthanasia. Changes in adiposity influenced the effect of RSTN on LRa mRNA transcript levels in the POA, ARC and AP and without detection of LRa in the VMH/DMH. Overall, both photoperiodic and nutritional signals influence the effects of RSTN on leptin transport to the CNS and are involved in the adaptive/pathological phenomenon of leptin resistance in sheep.

Changes in Expression of the Genes for the Leptin Signaling in Hypothalamic-Pituitary Selected Areas and Endocrine Responses to Long-Term Manipulation in Body Weight and Resistin in Ewes.

Both long-term undernutrition and overnutrition disturb metabolic balance, which is mediated partially by the action of two adipokines, leptin and resistin (RSTN). In this study, we manipulated the diet of ewes to produce either a thin (lean) or fat (fat) body condition and investigated how RSTN affects endocrine and metabolic status under different leptin concentrations. Twenty ewes were distributed into four groups (n = 5): the lean and fat groups were administered with saline (Lean and Fat), while the Lean-R (Lean-Resistin treated) and Fat-R (Fat-Resistin treated) groups received recombinant bovine resistin. Plasma was assayed for LH, FSH, PRL, RSTN, leptin, GH, glucose, insulin, total cholesterol, nonesterified fatty acid (NEFA), high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol and triglycerides. Expression levels of a suppressor of cytokine signaling (SOCS-3) and the long form of the leptin receptor (LRb) were determined in selected brain regions, such as the anterior pituitary, hypothalamic arcuate nucleus, preoptic area and ventro- and dorsomedial nuclei. The results indicate long-term alterations in body weight affect RSTN-mediated effects on metabolic and reproductive hormones concentrations and the expression of leptin signaling components: LRb and SOCS-3. This may be an adaptive mechanism to long-term changes in adiposity during the state of long-day leptin resistance.

Pregnancy-induced changes in the transcript levels of prolactin receptor and its suppressor in the ovine hypothalamus and adenohypophysis.

The aim of this study was to analyse changes in the abundance of prolactin (PRL) receptor (PRLR) and suppressor of cytokine signalling-3 (SOCS-3) mRNA in the ventro-/dorsomedial nucleus (VMH/DMH) and arcuate nucleus (ARC) of the hypothalamus as well as in the median eminence (ME) and adenohypophysis (AP) in sheep at 30, 60, 90 and 120 d of pregnancy compared to non-pregnant animals. In the VMH/DMH, PRLR transcripts were detected only in non-pregnant ewes. In the ARC, the abundances of PRLR mRNA were higher in pregnant sheep on days 30 (p < .01), 90 (p < .01) and 120 (p < .05) than in non-pregnant sheep. In contrast, the expression of PRLR mRNA in the ME was lower (p < .01) in pregnant ewes at days 30 and 60 than in non-pregnant ewes and was undetectable at later stages of gestation. In all studied stages of pregnancy except day 60, the abundance of PRLR mRNA was higher (p < .01) in the ARC than in the AP, while in non-pregnant sheep, there were no differences (p ≥ .05) in the transcript levels between these two tissues. In non-pregnant ewes, the abundance of SOCS-3 mRNA in the AP was lower than that in any other studied tissue (p < .05-p < .01). In conclusion, the observed changes in PRLR and SOCS-3 mRNA abundance in the hypothalamus and AP during pregnancy may be important components of the mechanisms regulating the action of PRL in energy homeostasis and neuroendocrine interactions within the hypothalamic-pituitary axis.

Involvement of orexin A in nocturnal melatonin secretion into the cerebrospinal fluid and the blood plasma in seasonal sheep.

In sheep, differences in orexin A (OXA) gene expression and activity are related to changes in energy demand and seasonal reproduction. However, the mechanism by which and the key place where the OXA signal is integrated with photoperiod, whose main biochemical expression is melatonin (MEL), remain unknown. We examined the effects of cisterna magna injections of OXA (0.3 µg/kg body weight) on nocturnal cerebrospinal fluid (CSF) and plasma MEL concentrations; mRNA and protein expression of two rate-limiting enzymes for MEL biosynthesis, tryptophan 5-hydroxylase-1 (TPH1) and arylalkylamine-N-acetyltransferase (AA-NAT); and OXA receptor (OX1R, OX2R) expression in the pineal gland (PG) obtained from twenty ewes during the short-day (SD) and long-day (LD) seasons. OXA increased (P < 0.001) CSF and plasma MEL concentrations regardless of the season. Plasma MEL was positively correlated (P < 0.001) with CSF MEL in the OXA-treated sheep in both seasons. OXA had no effect (P > 0.05) on TPH1 transcript or protein level but upregulated (P < 0.05) AA-NAT mRNA and protein expression in both seasons. OXA enhanced (P < 0.05) OX1R mRNA level only during the LD season. Our results show that the endocrine activity of the ovine PG is regulated by day length and non-photic signals via hypothalamic OXA. These results are important for understanding the work of the biological clock and recognizing mechanisms responsible for the adaptation of seasonal animals to the changing external environment conditions. OXA and MEL are both involved in the regulation of the sleep-wakefulness system, therefore our results can be used in the study on the circadian rhythm disorders in humans (e.g. jet lag, insomnia, seasonal depression).

Hypothalamic-Pituitary and Adipose Tissue Responses to the Effect of Resistin in Sheep: The Integration of Leptin and Resistin Signaling Involving a Suppressor of Cytokine Signaling 3 and the Long Form of the Leptin Receptor.

We hypothesized that resistin is engaged in the development of leptin central insensitivity/resistance in sheep, which is a unique animal model to explore reversible leptin resistance. Thirty Polish Longwool ewes, which were ovariectomized with estrogen replacement, were used. Treatments consisted of the intravenous injection of control (saline) or recombinant bovine resistin (rbresistin): control (Control; n = 10), a low dose of rbresistin (R1; 1.0 µg/kg body weight (BW); n = 10), and a high dose of rbresistin (R2; 10.0 µg/kg BW; n = 10). The studies were performed during short-day (SD) and long-day (LD) photoperiods. Leptin and resistin concentrations were determined. Expression levels of a suppressor of cytokine signaling (SOCS)-3 and the long form of the leptin receptor (LeptRb) were determined in selected brain regions, including in the anterior pituitary (AP), hypothalamic arcuate nucleus (ARC), preoptic area (POA), and ventro- and dorsomedial nuclei (VMH/DMH). The results indicate that resistin induced a consistent decrease in LeptRb (except in POA) and an increase in SOCS-3 expression during the LD photoperiod in all selected brain regions. In conclusion, the results demonstrate that the action of resistin appears to be strongly associated with photoperiod-driven changes in the leptin signaling pathway, which may underlie the phenomenon of central leptin resistance.

Assessment of changes in the occurrence of Fusarium toxin and ochratoxin A in Poland related to extreme weather phenomena

Background: Mycotoxins ­ substances harmful to humans, are ubiquitous in the environment. Mycotoxins are generated primarily by Penicilium, Aspergillus and Fusarium genus fungi. Their presence is associated with the unavoidable presence of mold fungi in the environment. The presently observed adverse climatic changes could negatively affect agriculture, causing erosion and loss of organic matter from soil, promulgation of pests and plant diseases, including those originating from pathogenic molds, and also migration of certain mold species into new regions, ultimately creating more favorable conditions for generation of mycotoxins. Objective: The purpose of this work was to investigate contamination of cereals in Poland with Fusarium and ochratoxin A. Elucidating a correlation between precipitation levels in the individual Provinces and reported levels of the investigated mycotoxins, referring to the generally available meteorological databases, would result in more efficient planning of sampling processes and focusing further preventive actions associated with establishing sampling plans for the following years. Material and methods: Investigations were performed on cereal and cereal product samples taken by the official foodstuffs inspection staff. Some 100 samples were taken annually in the 2009-2012 period (357 samples in total). Tests were performed using high performance liquid chromatography coupled with mass spectrometry (HPLC-MS/MS). Precipitation data were obtained from the Central Office of Statistics, based on data received from the Institute of Meteorology and Water Management. Results: Analysis of the influence of precipitation levels during vegetation period on mycotoxin levels in the investigated foodstuffs was performed by associating each recorded content of deoxynivalenol (n=52, corresponding to 14.6% tested samples), zearalenone (n=30, 8.4%), total T-2 and HT-2 toxins (n=21, 5.9%) and ochratoxin A (n=88, 24.6%) above quantification limit with precipitation levels within the Province from which the sample originated. Deoxynivalenol and zearalenone levels show distinct variability corresponding with variability of precipitation levels, well reflecting the reported higher deoxynivalenol and zearalenone levels observed during the rainy years of 2011-2012. Variability in average ochratoxin A levels was not statistically significant. The relatively higher mycotoxin levels in 2009 may result from the heavy rainfall and flooding of 2007-2008. Dependence between the precipitation levels and number of samples showing levels above quantification limit has been also observed for deoxynivalenol. However, a similar analysis made for zearalenone and ochratoxin A does not point to any significant relationship. No data analysis was possible in reference to total T-2 and HT-2 toxins content due to the insufficient number of results available. However, it should be noted that 21% analyzed samples in 2009 contained T-2 and HT-2 levels above the quantification limit, with average of 8.9 µg/kg, whereas in 2010-2012 only one sample of the 263 tested contained contaminants in quantities above the quantification limit. Conclusions: The model used for forecasting presence of mycotoxins in cereals does not allow its practical application during routine generation of official control and monitoring plans on national scale. Notably, tests performed show that exceeding of maximum contamination levels occurred just incidentally, notwithstanding the adverse weather conditions. Further systematic collection of data on mycotoxin contamination of agricultural crops is required for effective continued investigations.

Exposure assessment of infants and young children on selected Fusarium toxins

Background: Mycotoxins belong to substances harmful to human health. They are found mainly in cereal products and their preparations. In particular, infants and young children who consume cereal products, including porridge and gruel, are exposed to these substances. Objective: The aim of the study is to assess the exposure of infants and young children in Poland to micotoxins (ochratoxin A. deoxynivalenol, nivalenol, fumonisins B1 and B1, T-2 and HT-2 toxins) derived from cereal products intended for infants and children. Material and methods: Samples of products (302) were taken from all over the country in the following three years (2011, 2012 and 2013). HPLC-MS / MS method was used to determine the test compounds. Results: Using the HPLC-MS / MS method, the assessment of population exposure in Poland to mikototoxins (ochratoxin A, deoxynivalenol, nivalenol, fumonisins B1 and B1, T-2 and HT-2 toxins) derived from cereal products (porridge, gruel) intended for infants and small children. Samples (302) were taken from across the country over the next three years. The exposure values obtained in the average exposure scenario range from 0.2 to 3% compared to the reference toxicological parameters. Considering that in the case of infants and young children, the tested products constitute a quantitatively significant part of the balanced diet of these consumers, and the remaining groups of foodstuffs, including vegetable products. fruit and meat and dairy products do not contribute significant amounts of mycotoxins to the diet can be accepted. that the level of contamination of cereal products does not pose a significant risk to the health of consumers. In the case of high exposure, it did not exceed 10% of the reference values for deoxynivalenol and the sum of fumonisins B1 and B2. These values were assessed as not relevant for the exposure of infants and young children. In contrast, in the case of zearalenone, the high level of exposure corresponded to 36% of the value of tolerable daily intake (TDI), and for the sum of T-2 and HT-2 toxins, the value of 48% of tolerable daily intake. In both cases, the contribution of pollutants to the diet was significant, but still remained 2-3 times less than the tolerable daily intake. Given, that cereal products are the main source of these contaminants, it can be estimated that exceeding the TDI value in relation to the total diet of infants and young children is unlikely. Conclusions: The exposure values obtained in the average exposure scenario range from 0.2 to 3% compared to the reference toxicological parameters. In the case of zearalenone, the high level of exposure corresponded to 36% of the TDI value. and for the sum of T-2 and HT-2 toxins, 48% TDI. The contribution of pollutants to the diet in both cases was significant. however, it still remained 2-3 times less than the tolerable daily intake. Considering, that cereal products are the main source of these pollutants can be assessed. that exceeding the TDI value for the total diet of infants and young children is unlikely.

Downregulation of LRb in VMH/DMH during the second half of gestation and upregulation of SOCS-3 in ARC in late-pregnant ewes - Implications for leptin resistance.

To investigate factors involved in pregnancy-induced regulation of tissue sensitivity to leptin, we determined leptin concentrations and expression levels of the long form of the leptin receptor (LRb) and suppressor of cytokine signalling (SOCS)-3 in the ventro- and dorsomedial nuclei (VMH/DMH), arcuate nucleus (ARC), median eminence (ME) and anterior pituitary (AP) in 15 Polish Longwool ewes euthanized at 30, 60, 90 and 120 days of pregnancy and before gestation (n = 3 per group). Leptin concentrations increased during the first half of pregnancy, peaked on day 60, and then declined. In the VMH/DMH, LRb mRNA levels decreased from day 60 of pregnancy; in the ARC, LRb mRNA levels remained stable before and throughout pregnancy. LRb expression in the ME was lower in the first two months of pregnancy than before pregnancy (P < 0.01) and peaked at day 90. In the AP, LRb mRNA levels were higher during mid-pregnancy (P < 0.05) than before pregnancy. SOCS-3 expression in the VMH/DMH was higher throughout gestation (P < 0.05) than before pregnancy but was undetectable at day 120. SOCS-3 transcript levels were higher in the ARC (P < 0.05) in late-pregnancy (at day 120) than in non-pregnant ewes. SOCS-3 mRNA levels in the ME were lower at days 30 and 60 (P < 0.05) than at day 120 or before pregnancy. In the AP, SOCS-3 transcription was stable throughout gestation except at day 120, when it increased (P < 0.05). The changes in plasma leptin concentrations during pregnancy, hypothalamic LRb downregulation in the VMH/DMH during the second half of gestation and SOCS-3 upregulation in the ARC in late-pregnant ewes identified here may be essential components of the mechanisms driving ovine leptin insensitivity.

The Action of Di-(2-Ethylhexyl) Phthalate (DEHP) in Mouse Cerebral Cells Involves an Impairment in Aryl Hydrocarbon Receptor (AhR) Signaling.

Di-(2-ethylhexyl) phthalate (DEHP) is used as a plasticizer in various plastic compounds, such as polyvinyl chloride (PVC), and products including baby toys, packaging films and sheets, medical tubing, and blood storage bags. Epidemiological data suggest that phthalates increase the risk of the nervous system disorders; however, the impact of DEHP on the brain cells and the mechanisms of its action have not been clarified. The aim of the present study was to investigate the effects of DEHP on production of reactive oxygen species (ROS) and aryl hydrocarbon receptor (AhR), as well as Cyp1a1 and Cyp1b1 mRNA and protein expression in primary mouse cortical neurons and glial cells in the in vitro mono-cultures. Our experiments showed that DEHP stimulated ROS production in both types of mouse neocortical cells. Moreover, the results strongly support involvement of the AhR/Cyp1A1 signaling pathway in the action of DEHP in neurons and glial cells. However, the effects of DEHP acting on the AhR signaling pathways in these two types of neocortical cells were different. In neurons, AhR mRNA expression did not change, but AhR protein expression decreased in response to DEHP. A similar trend was observed for Cyp1a1 and Cyp1b1 mRNA and protein expression. Failure to induce Cyp1a1 in neurons was confirmed by EROD assay. In primary glial cells, a decrease in AhR protein level was accompanied by a decrease in AhR mRNA expression. In glial cells, mRNA and protein expression of Cyp1a1 as well as Cyp1a1-related EROD activity were significantly increased. As for Cyp1b1, both in neurons and glial cells Cyp1b1 mRNA expression did not significantly change, whereas Cyp1b1 protein level were decreased. We postulate that developmental exposure to DEHP which dysregulates AhR/Cyp1a1 may disrupt defense processes in brain neocortical cells that could increase their susceptibility to environmental toxins.

Resistin regulates reproductive hormone secretion from the ovine adenohypophysis depending on season.

Work in cattle and rodents has shown that resistin, in addition to its roles in insulin resistance and inflammation, is involved in the regulation of gonadal steroidogenesis. However, the role of resistin in the regulation of reproductive processes in other species, such as seasonally breeding sheep, is completely unknown. Herein, we tested the hypothesis that resistin can influence the secretion of anterior pituitary hormones and that its effect in ewes is dependent on the day length. Thirty Polish Longwool ewes, a breed that exhibits a strong seasonal reproductive pattern, were ovariectomized with estrogen replacement using subcutaneously inserted estradiol implants. Ewes were fed ad libitum and housed under a natural photoperiod (longitude: 19°57' E, latitude: 50° 04' N). Intravenous treatments consisted of control or recombinant bovine resistin (rbresistin) in saline: (1) control (saline; n = 10), (2) low resistin dose (1.0 µg/kg BW; n = 10), and (3) high resistin dose (10.0 µg/kg BW; n = 10). Experiments were conducted during both short-day (SD) and long-day (LD) seasons using 5 sheep per group within each season. Blood samples were collected every 10 min over 4 h. Blood plasma concentrations of FSH, LH, and prolactin (PRL) were assayed using RIA. A season × dose interaction was observed for all hormonal variables measured. Greater concentrations (P < 0.001) of LH and FSH were observed during SDs than during LDs in all groups. During SDs, the high dose (10 µg/kg BW) decreased (P < 0.001) basal LH levels and amplitude (P < 0.05) of LH pulses and increased (P < 0.001) circulating concentrations of FSH. However, the low dose of resistin decreased (P < 0.001) FSH concentrations compared to those of controls. During LDs, both the low and high resistin doses increased mean concentrations of LH (P < 0.001 and P < 0.05, respectively) and FSH (P < 0.001). A high dose of rbresistin increased (P < 0.001) the mean circulating concentrations of PRL during both seasons. However, in all groups, concentrations of PRL were greater during LDs than SDs. These results demonstrate for the first time that resistin is involved in the regulation of pituitary hormone secretion and that this effect is differentially mediated during LDs and SDs.

The effects of leptin on plasma concentrations of prolactin, growth hormone, and melatonin vary depending on the stage of pregnancy in sheep.

The effects of hyperleptinemia and leptin resistance during gestation are unclear. Leptin, an important neuroendocrine regulator, has anorexic effects, but its interactions with other metabolic hormones during pregnancy are unclear. We examined potential roles of leptin in regulating prolactin (PRL), GH, and melatonin plasma concentrations during pregnancy in Polish Longwool ewes. Twelve estrus-synchronized ewes carrying twins after mating were randomly assigned to receive i.v. injections of saline or recombinant ovine leptin (2.5 or 5.0 µg/kg BW). Blood samples were collected (15-min intervals over 4 h) immediately before the first injection at dusk and kept under red light. Treatments were repeated at 2-wk intervals, starting before mating and continuing from days 30 to 135 of gestation. Concentrations of plasma PRL, GH, and melatonin were determined using a validated RIA. The effects of leptin on hormone plasma concentrations varied depending on pregnancy stage and leptin dose. PRL plasma concentrations were affected at most stages of pregnancy and before gestation. In non-, very early- (day 30), and late- (day 120 and 135) pregnant ewes, exogenous leptin stimulated PRL (P < 0.001) plasma concentrations, while during the second month of gestation, it decreased PRL concentrations (P < 0.01). Leptin affected GH plasma concentrations (P < 0.05) only during the first 2 mo of pregnancy, with no effects during the second part of gestation or before pregnancy. In early-pregnant ewes (day 30 and 45), leptin decreased melatonin plasma concentrations (P < 0.05), but at day 60, leptin stimulated melatonin plasma concentrations at low (P < 0.01) and high doses (P < 0.05), with no effects in ewes after 105 d of gestation. These data indicate specific pregnancy-induced endocrine adaptations to changes in energy homeostasis, supporting the hypothesis that leptin affects PRL, GH, and melatonin release during gestation.

[Studies and safety evaluation of aflatoxins in herbal plants]. / Badania i ocena bezpieczenstwa surowcow zielarskich w zakresie zanieczyszczenia aflatoksynami.

Herbs and herbal products are commonly used in food and pharmaceutical industries. The aim of this study was to test herbal plants for contamination with aflatoxins (AF), genotoxic, cancerogenic and hepatotoxic compounds which can cause immunotoxic and allergic effects as well as growth disorders. Aflatoxins were determined by high performance liquid chromatography (HPLC) with post column derivatization involving bromination with pyridinium hydrobromide perbromide (PBPB). Extracts was cleaned-up by immunoaffinity columns (IAC). The contents of aflatoxins B, B, G, and G, in more than 500 herbal plants samples mainly from Eastern Poland were investigated. Samples were supplied by manufacturers (herbal facilities) in 2006-2010 years. In all the evaluated samples the levels of aflatoxins above the detection limits of methods applied were not observed: for AF B1--0.2 microg/kg; AF B2--0.03 microg/kg; AF G1--0.3 microg/kg; AF G2--0.03 microg/kg (PN-EN 14123) and for AF B1--0.15 microg/kg (Ph. Eur.6, 2008:2.8.18). All the herbal plants tested for contamination with aflatoxins should be considered safe, which indicates that manufacturers used good manufacturing practices during drying and storage of raw materials.

[Monitoring programs realized by the State Sanitary Inspection concerning the contamination of selected foodstuffs by mycotoxins]. / Programy monitoringowe realizowane przez Panstwowa Inspekcje Sanitarna w zakresie zanieczyszczenia wybranych srodkow spozywczych mikotoksynami.

National monitoring plans, concerning mycotoxins levels in foodstuffs of plant origin in Poland are showed. The official control program for contaminates in food, including mycotoxins, is created by Chief Sanitary Inspectorate, on the basis of the draft prepared in National Institute of Hygiene and approved by Chief Sanitary Inspector. Results of monitoring programme for domestic market: aflatoxins in selected foodstuffs, mycotoxins in baby food and Fusarium toxin in baby food and maize-based foodstuffs, in years 2004-2006 were presented.

[Monitoring programme of T-2 and HT-2 toxins level in cereal products]. / Badania monitoringowe w zakresie oznaczania poziomu toksyn T-2 i HT-2 w przetworach zbozowych.

In framework of the national monitoring program in Poland HPLC method for determination of T-2 and HT-2 toxins in cereal products was developed, validated and accredited. Simply, one-step extraction and HPLC MS/MS ESI+ method was used for determination both toxins. Performance of method (recovery, precision and uncertainty of results) is in line with Commission Regulation No 401/2006. Limit of detection for T-2 and HT-2 toxins is 3 ad 4 microg/kg, respectively. Samples were taken by sanitary inspection from all region of country. 107 samples cereal products (mainly from oats) were tested. T-2 and HT-2 toxins were detected in 43% samples, mean level in oats products was 22.5 microg/kg (maximum level 109 microg/kg in oat flakes), in other samples (wheat and barley flakes, grouts, flours) - 7.0 microg/kg. Intake of T-2/HT-2 toxin by the consumer in Poland is much lower than the TDI.

[European Union legislation related to patulin]. / Nowe przepisy Unii Europejskiej w zakresie patuliny.

In the following review, European Union legislation concerning maximum level of patulin in foodstuffs was reported. Commission Regulation (EC) No 1425/2003 of 11 August 2003 amending Regulation (EC) No 466/2001, Commission Directive 2003/78/EC of 11 August 2003 laying down the sampling methods and the methods of analysis for the official control of the levels of patulin in foodstuffs and Commission Recommendation of 11 August 2003 on the prevention and reduction of patulin contamination in apple juice and apple juice ingredients in other beverages as regards patulin was reported.