Genome-wide mRNA profiling identifies X-box-binding protein 1 (XBP1) as an IRE1 and PUMA repressor

Accumulation of misfolded proteins in ER activates the unfolded protein response (UPR), a multifunctional signaling pathway that is important for cell survival. The UPR is regulated by three ER transmembrane sensors, one of which is inositol-requiring protein 1 (IRE1). IRE1 activates a transcription factor, X-box-binding protein 1 (XBP1), by removing a 26-base intron from XBP1 mRNA that generates spliced XBP1 mRNA (XBP1s). To search for XBP1 transcriptional targets, we utilized an XBP1s-inducible human cell line to limit XBP1 expression in a controlled manner. We also verified the identified XBP1-dependent genes with specific silencing of this transcription factor during pharmacological ER stress induction with both an N-linked glycosylation inhibitor (tunicamycin) and a non-competitive inhibitor of the sarco/endoplasmic reticulum Ca²⁺ ATPase (SERCA) (thapsigargin). We then compared those results to the XBP1s-induced cell line without pharmacological ER stress induction. Using next‐generation sequencing followed by bioinformatic analysis of XBP1-binding motifs, we defined an XBP1 regulatory network and identified XBP1 as a repressor of PUMA (a proapoptotic gene) and IRE1 mRNA expression during the UPR. Our results indicate impairing IRE1 activity during ER stress conditions accelerates cell death in ER-stressed cells, whereas elevating XBP1 expression during ER stress using an inducible cell line correlated with a clear prosurvival effect and reduced PUMA protein expression. Although further studies will be required to test the underlying molecular mechanisms involved in the relationship between these genes with XBP1, these studies identify a novel repressive role of XBP1 during the UPR.

Regulation of the abundance of Y-family polymerases in the cell cycle of budding yeast in response to DNA damage

Y-family DNA polymerases mediate DNA damage tolerance via translesion synthesis (TLS). Because of the intrinsically error-prone nature of these enzymes, their activities are regulated at several levels. Here, we demonstrate the common regulation of the cellular abundance of Y-family polymerases, polymerase eta (Pol eta), and Rev1, in response to DNA damage at various stages of the cell cycle. UV radiation influenced polymerase abundance more when cells were exposed in S-phase than in G1- or G2-phases. We noticed two opposing effects of UV radiation in S-phase. On one hand, exposure to increasing doses of UV radiation at the beginning of this phase increasingly delayed S-phase progression. As a result, the accumulation of Pol eta and Rev1, which in nonirradiated yeast is initiated at the S/G2-phase boundary, was gradually shifted into the prolonged S-phase. On the other hand, the extent of polymerase accumulation was inversely proportional to the dose of irradiation, such that the accumulation was significantly lower after exposure to 80 J/m² in S-phase than after exposure to 50 J/m² or 10 J/m². The limitation of polymerase accumulation in S-phase-arrested cells in response to high UV dose was suppressed upon RAD9 (but not MRC1) deletion. Additionally, hydroxyurea, which activates mainly the Mrc1-dependent checkpoint, did not limit Pol eta or Rev1 accumulation in S-phase-arrested cells. The results show that the accumulation of Y-family TLS polymerases is limited in S-phase-arrested cells due to high levels of DNA damage and suggest a role of the Rad9 checkpoint protein in this process.

Genome-wide mRNA profiling identifies RCAN1 and GADD45A as regulators of the transitional switch from survival to apoptosis during ER stress

Endoplasmic reticulum (ER) stress conditions promote a cellular adaptive mechanism called the unfolded protein response (UPR) that utilizes three stress sensors, inositol-requiring protein 1, protein kinase RNA-like ER kinase, and activating transcription factor 6. These sensors activate a number of pathways to reduce the stress and facilitate cell survival. While much is known about the mechanisms involved that modulate apoptosis during chronic stress, less is known about the transition between the prosurvival and proapoptotic factors that determine cell fate. Here, we employed a genetic screen that utilized three different pharmacological stressors to induce ER stress in a human-immortalized airway epithelial cell line, immortalized human bronchial epithelial cells. We followed the stress responses over an 18-h time course and utilized real-time monitoring of cell survival, next-generation sequencing, and quantitative real-time PCR to identify and validate genes that were upregulated with all three commonly employed ER stressors, inhibitor of calpain 1, tunicamycin, and thapsigargin. growth arrest and DNA damage-inducible alpha (GADD45A), a proapoptotic factor, and regulator of calcineurin 1 (RCAN1) mRNAs were identified and verified by showing that small interfering RNA (siRNA) knockdown of GADD45A decreased CCAAT-enhancer-binding protein homologous protein (a.k.a DDIT3), BCL2-binding component 3 (a.k.a. BBC3), and phorbol-12-myristate-13-acetate-induced protein 1 expression, 3 proapoptotic factors, and increased cell viability during ER stress conditions, whereas siRNA knockdown of RCAN1 dramatically decreased cell viability. These results suggest that the relative levels of these two genes regulate cell fate decisions during ER stress independent of the type of ER stressor.

Effects of in ovo injection of prebiotics and synbiotics on the productive performance and microstructural features of the superficial pectoral muscle in broiler chickens

The aim of the study was to compare the effects of 2 prebiotics and 2 synbiotics injected in ovo on productivity parameters, quality, and microstructure of the superficial pectoral muscle in 35-day-old broiler chickens. On day 12 of incubation, 9,000 eggs Ross 308 were randomly divided into 5 experimental groups treated with different bioactives in ovo injected: C, control with physiological saline; PI, with 1.760 mg inulin; PB, with 0.528 mg of commercial prebiotic Bi2tos; SI, with 1.760 mg inulin and 1,000 CFU Lactococcus lactis spp. lactis IBB SL1; SB, with 0.528 mg Bi2tos and 1,000 CFU Lactococcus lactis spp. cremoris IBB SC1. The synbiotic solution contained 20 μl bacterial suspension and 180 μl prebiotic solution. For productive parameters and further tests ten male birds for each experimental group were used. The birds were slaughtered on day 35 of age. At slaughter, samples of the left pectoral muscles were taken and preserved by freezing in liquid nitrogen. The pH and color of the meat were evaluated at 45 min and 24 h post-mortem. Water holding capacity (WHC) was measured and expressed as the percentage of free water in meat. Microscopic specimens were analysed using MultiScan software for the measurement of the percentage of oxidative and glycolytic fibres and mean diameter of the muscle fibres. In ovo injection of prebiotics Bi2tos had a positive effect on body weight. In prebiotic group (PI) a negative impact on hatchability was observed. Prebiotics and synbiotics had no influence on the yield of the carcass and pectoral muscle. Bioactive compounds had a significant effect on the quality of meat parameters such as: pH 24 h (PI and PB group), L* 45' (SI and SB group), and WHC (groups PB, SI, and SB). The analysis of the enzymatic profile showed a significant increase in the percentage of glycolytic fibres in the pectoral muscle from chicken treated with a synbiotic with the addition of inulin (group SI).

Aspects of ageing on professional opera singer's voice - preliminary findings

OBJECTIVES

The main goals of this study were to assess the most significant morphological changes and acoustic measures for the ageing process of a professional opera singer's voice.

DESIGN

This investigation included 58 healthy professional opera singers, who were compared with 42 young opera singers from the control group.

METHODS

All participants underwent a voice assessment protocol: ENT specialist examination and speech therapist evaluation. Acoustic parameters and subjective observations were obtained and analysed. R esults: Fundamental frequency (F0) level was distinctly decreased in the case of older female singers, but F0 in older male singers had stable levels in comparison to that in younger singers. Older singers were found not to have substantially different values of jitter than younger ones. Maximal phonation time (MPT) was longer in the older women's group when compared to the younger singers, but not relatively different in the men's group. Shimmer value presented no age-related change. Morphological changes seem to correlate with the age of subjects. C onclusions: The main characteristic of voice change with age was a decreased F0 level among older female professional singers and rather stable F0 levels in male singers. This study gives preliminary results on the ageing of voice in the population of professional opera singers.

DNA polymerase ι is acetylated in response to SN2 alkylating agents

DNA polymerase iota (Polι) belongs to the Y-family of DNA polymerases that are involved in DNA damage tolerance through their role in translesion DNA synthesis. Like all other Y-family polymerases, Polι interacts with proliferating cell nuclear antigen (PCNA), Rev1, ubiquitin and ubiquitinated-PCNA and is also ubiquitinated itself. Here, we report that Polι also interacts with the p300 acetyltransferase and is acetylated. The primary acetylation site is K550, located in the Rev1-interacting region. However, K550 amino acid substitutions have no effect on Polι's ability to interact with Rev1. Interestingly, we find that acetylation of Polι significantly and specifically increases in response to SN2 alkylating agents and to a lower extent to SN1 alkylating and oxidative agents. As we have not observed acetylation of Polι's closest paralogue, DNA polymerase eta (Polη), with which Polι shares many functional similarities, we believe that this modification might exclusively regulate yet to be determined, and separate function(s) of Polι.

Surgical treatment in children with otosclerosis and congenital stapes fixation: our experience and outcome

AIM

To evaluate outcomes of stapes surgery in children with congenital stapes fixation and juvenile otosclerosis.

METHODS

A retrospective chart review was performed from 1987 to 2013 to identify patients under 18 years old who underwent a stapes surgery. Patients' age, gender, pre- and postoperative audiograms, intraoperative findings including aetiology of stapes fixation, prosthesis type, and complications were analysed.

RESULTS

18 children (6 - 17 years old), all with bilateral conductive hearing loss were identified and 34 stapes surgeries were performed (two patients underwent surgery only on one side). The cause of fixation included juvenile otosclerosis in 88% and congenital stapes fixation in 12%. The mean pre-operative air-bone gap (ABG) was 36,24 dB (SD: 10,86) compared to a postoperative mean ABG of 7,74 (SD: 3,3) (p < 0.000). The profound sensorineural hearing loss was not observed in long-term follow-up.

CONCLUSIONS

Paediatric stapes surgery has comparable results to stapedectomy in adults regardless of the cause of stapes fixation; however, the better hearing outcome was observed for cases of juvenile otosclerosis rather than congenital stapes fixation.

Chronic stress changes prepulse inhibition after amphetamine challenge: the role of the dopaminergic system

The goal of this research was to examine the influence of chronic mild stress (CMS) on prepulse inhibition (PPI). We used an amphetamine challenge to study the role of the dopaminergic system in limbic structures. Chronic stress caused a reduction in both sucrose preference and body weight. It was found that the initially strong response to amphetamine in the control rats was weakened after stress on both the behavioural and biochemical levels: improved PPI, decreased dopamine D2 receptor expression in the central nucleus of amygdala (CeA) and nucleus accumbens (NAC), and decreased dopamine and 3-MT (3-methoxytyramine) levels in NAC. We observed that the stress-evoked attenuation of amphetamine-induced stimulation was also paralleled by changes in corticosterone level. These effects were accompanied by a decrease in both glutamate and the glutamate/gamma-aminobutric acid (GABA) ratio in the NAC. The interpretation of these results is that prolonged stress induces compensatory mechanisms in the mesolimbic system which are responsible for psychostimulant (amphetamine) effects.

microRNA single polynucleotide polymorphism influences on microRNA biogenesis and mRNA target specificity

microRNAs (miRNAs) are nowadays recognized as an essential component of gene regulatory networks. Furthermore, deregulation of miRNAs expression often contributes to human pathologies. Recently, a substantial number of single nucleotide polymorphism (SNPs) and rare mutations within pri-, pre- and mature miRNA sequences have been reported. These miRNA SNPs have often been associated with human disease. However, due to the complexity of miRNA biogenesis and the genome-wide functional effects of miRNAs, the determination of biological consequences of these miRNA SNPs remains challenging. Despite an increasing number of reports linking miRNA SNPs with human pathologies, few reports have analyzed the mechanism by which miRNA-SNPs contribute to disease pathogenesis. In this review, we discuss how single polynucleotide polymorphisms in miRNAs genes may influence miRNAs expression and function and thus potentially alter disease pathogenesis.

The impact of synbiotic administration through in ovo technology on the microstructure of a broiler chicken small intestine tissue on the 1st and 42nd day of rearing

Background

Application the innovative method which is in ovo technology provides a means of modulating the immune system at early embryonic stages. The aim of study was to determine influence of the in ovo stimulation, on d 12 of incubation, with synbiotics (synbiotic 1- L. salivarius IBB3154 + Bi²tos, Clasado Ltd. and the synbiotic 2 - L. plantarum IBB3036 + lupin RFOs) on the microstructure of duodenum, jejunum and ileum in the 1^st and 42^nd day of rearing.

Results

On the 1^st day of chickens life, in the duodenum of both experimental groups (SYN1 and SYN2), a significantly higher and wider intestinal villi as well as a significantly larger absorbent surface of these villi were found in comparison with the Control group (P ≤ 0.01). On the 42^nd day of rearing the beneficial effect of synbiotic 1 was reflected by the numerically higher villi (no statistical differences) with a larger surface (P ≤ 0.01) in the duodenum in the SYN1 group compare to the Control group. In the jejunum on the 1^st day of life, in the SYN1 group, significantly higher villi than in the Control group, with a simultaneous decrease in the depth of crypts (P ≤ 0.01), and also the largest width of villi and their absorbent area (P ≤ 0.01) in comparison to the other groups were found. On the 42^nd day of life, in the jejunum, an increase in the height of the villi whilst reducing the crypt depth in the SYN2 group was found (P ≤ 0.01). In turn, in the SYN1 group, there were significantly more neutral goblet cells observed compared with the control group (P ≤ 0.05). In the ileum of 1-day-old chickens, the widest villi (P ≤ 0.05) and the deepest crypts (P ≤ 0.01) were found in the SYN2 group. In the same group, there was also the least amount of neutral goblet cells in comparison to the other groups (P ≤ 0.05).

Conclusions

We observed that synbiotic 1 and 2 beneficially affected the examined characteristics on the 1^st and 42^nd day of life. The obtained results allow us to conclude that the use of synbiotics significantly affect gut structure which should contribute to improvement in nutrient absorption by the gut.

Corticotropin releasing factor receptor 1 antagonist differentially inhibits freezing behavior and changes gamma-aminobutyric acidergic activity in the amygdala in low- and high-anxiety rats

The aim of this study was to examine the effects of non-peptide corticotropin-releasing factor receptor 1 (CRF₁) antagonist (antalarmin) administration on rat conditioned fear responses and gamma-aminobutyric acid (GABA)-ergic brain activity (GAD67 expression and GABA concentration) in low-anxiety (LR) and high-anxiety (HR) rats. The animals were divided into the LR and HR groups based on the duration of their conditioned freezing response in the first contextual fear test. After 28 days, the animals were re-subjected to the contextual fear training and test. The rats received an antalarmin injection (10 mg/kg or 20 mg/kg) 80 min before the second exposure to the aversive context. Antalarmin significantly attenuated the conditioned fear response only in the HR rats. The behavioral effect of a lower dose (10 mg/kg) of antalarmin was accompanied by increased GAD67 expression in the prelimbic cortex (PL) and central nucleus of the amygdala (CeA) and an increased GABA concentration in the amygdala. These studies showed that HR rats were more susceptible to the anxiolytic effects of CRF₁ antagonist administration, which were associated with increased GABAergic activity in the medial prefrontal cortex and amygdala. The current data may provide insights into the neurobiological mechanism operating within the mesolimbic CRF-GABA neurotransmitter systems, which may be responsible for individual differences in stress-related diseases. This knowledge can be applied to further elucidate the pathophysiology of anxiety and trauma/stress-related disorders.

Codon bias and the folding dynamics of the cystic fibrosis transmembrane conductance regulator

Synonymous or silent mutations are often overlooked in genetic analyses for disease-causing mutations unless they are directly associated with potential splicing defects. More recent studies, however, indicate that some synonymous single polynucleotide polymorphisms (sSNPs) are associated with changes in protein expression, and in some cases, protein folding and function. The impact of codon usage and mRNA structural changes on protein translation rates and how they can affect protein structure and function is just beginning to be appreciated. Examples are given here that demonstrate how synonymous mutations alter the translational kinetics and protein folding and/or function. The mechanism for how this occurs is based on a model in which codon usage modulates the translational rate by introducing pauses caused by nonoptimal or rare codons or by introducing changes in the mRNA structure, and this in turn influences co-translational folding. Two examples of this include the multidrug resistance protein (p-glycoprotein) and the cystic fibrosis transmembrane conductance regulator gene (CFTR). CFTR is also used here as a model to illustrate how synonymous mutations can be examined using in silico predictive methods to identify which sSNPs have the potential to change protein structure. The methodology described here can be used to help identify "non-silent" synonymous mutations in other genes.

Comfort During Digital Rectal Examination - Patient Preference

The sex and age of the physician performing the digital rectal examination (DRE) procedure is one of the parameters influencing patients' comfort. It is postulated that the stress related to DRE during admission to the surgical ward may affect the compliance. The aim of the study was to characterize patients' preferences according to their sex, age, socioeconomic status and according to DRE-related variables.

MATERIAL AND METHODS

Patients admitted to the Department of General and Colorectal Surgery at Medical University in Łódź between October 2014 and June 2015 were asked to complete a questionnaire regarding their sex, age, ethnic background, socioeconomic status and preference for a physician performing the DRE during admission to the surgical ward.

RESULTS

The study enrolled 225 patients, 52% (n=117) women and 48% (n=108) men. Most patients 73.3% (n=244) expressed no preference for sex of the physician performing the DRE during admission, while 22.7% (n=51) preferred a same-sex physician. Analysis showed that the age, female sex, lower education status, small amount of comorbidities and number of hospitalizations, and no previous colonoscopy experience were all associated with preference for a same-sex physician.

CONCLUSIONS

In our study most patients expressed no preference for sex of the physician performing the DRE during admission to the surgical ward. However, over one-tenth of patients reported such preferences. Most of these patients preferred a same-sex physician. It is important to offer these patients the choice of physician performing the DRE. Addressing patients' preferences may improve the atmosphere in the clinical environment, reduce stress, and facilitate better treatment.

Correlations between skin lesions induced by anti-tumor necrosis factor-α and selected cytokines in Crohn's disease patients

AIM: To investigate the correlation between the appearance of skin lesions and concentration of interleukin (IL)-17A, IL-23 and interferon-γ (IFN-γ) in Crohn’s disease (CD) patients during anti-tumor necrosis factor-α (TNF-α) therapy

METHODS: A prospective study included 30 adult patients with CD of Caucasian origin (19 men and 11 women; mean age ± SD 32.0 ± 8.6 years) during biological therapy with anti-TNF-α antibodies from January 2012 to March 2013. Eighteen patients were treated with infliximab, seven with adalimumab and five with certolizumab. Inclusion criteria were exacerbation of the underlying disease, Crohn’s Disease Activity Index over 300 and the ineffectiveness of previously used non-biological therapies. Patients with a history of psoriasis, atopic dermatitis and other autoimmune skin lesions were excluded from the study. The control group consisted of 12 healthy subjects. A diagnostic survey was carried out, blood tests and careful skin examination were performed, and the serum levels of IL-17, IL-23 and IFN-γ were measured using an enzyme-linked immunosorbent assays technique. Dermatoses that have developed in the course of biological therapy in patients who had no pre-existing skin lesions of similar character were qualified as skin lesions induced by anti-TNF-α therapy.

RESULTS: Skin manifestations occurred in 18 of CD patients during the anti-TNF-α therapy (60%), in the average time of 10.16 ± 3.42 mo following the beginning of the 52-wk treatment cycle. Skin lesions observed in CD patients during biological therapy included psoriasiform lesions (44.4%), and eczema forms lesions (22.2%). In CD patients with drug induced skin lesions significantly higher levels of hemoglobin (13.3 ± 1.5 g/dL vs 10.8 ± 1.9 g/dL, P = 0.018) and hematocrit (39.9% ± 4.5% vs 34.3% ± 5.4%, P = 0.01), as well as a significantly lower level of platelets (268 ± 62 × 10³/μL vs 408 ± 239 × 10³/μL, P = 0.046) was observed compared with CD patients without skin manifestations. The concentrations of IL-17A and IL-23 in CD patients with skin lesions developed under anti-TNF-α therapy were significantly higher compared to those in patients without lesions (IL-17A: 39.01 ± 7.03 pg/mL vs 25.71 ± 4.90 pg/mL, P = 0.00004; IL-23: 408.78 ± 94.13 pg/mL vs 312.15 ± 76.24 pg/mL, P = 0.00556).

CONCLUSION: Skin lesions in CD patients during biological therapy may result from significantly increased concentrations of IL-17A and IL-23, which are strongly associated with TNF-α/Th1 immune pathways.

The effects of electrical hippocampal kindling of seizures on amino acids and kynurenic acid concentrations in brain structures

Our study demonstrated that the development of seizures during the electrically induced kindling of seizures is associated with significant changes in the concentration of kynurenic acid (KYNA) and its precursor, tryptophan (TRP). The primary finding of our study was an increase in KYNA levels and the KYNA/TRP ratio (a theoretical index of activity of the kynurenine pathway) in the amygdala and hippocampus of kindled animals. We also found decreases in the concentration of tryptophan in the hippocampus and prefrontal cortex. Changes in the concentration of KYNA and TRP in the amygdala were accompanied by a significant decrease in γ-Aminobutryic Acid (GABA) levels and an increase in the glutamate/GABA ratio. Moreover, we found a significant negative correlation between the local concentrations of KYNA and glutamate in the amygdala of kindled rats. However, there were no changes in the local concentrations of the following amino acids: glutamate, aspartate, glutamine, glycine, taurine and alanine. In conclusion, these new results suggest a modulatory influence of KYNA on the process of epileptogenesis, characterized by a negative relationship between the KYNA and glutamate systems in the amygdala.

Expression of N-methyl-D-aspartate (R)(GluN2B) - subunits in the brain structures of rats selected for low and high anxiety

In this paper, we studied differences in the density of N-methyl-D-aspartate (NMDA) receptor GluN2B subunits in the brains of low (LR) and high (HR) anxiety rats subjected to extinction trials and re-learning of a conditioned fear response, modeling a natural course of anxiety disorders. Classifications of animals as LR or HR was determined by fear-induced freezing responses in the contextual fear test. Increased basal concentrations of GluN2B subunits were observed in the amygdala of HR rats as compared to the unconditioned control group by Western blot analysis. Re-exposure of HR animals to the fear-conditioned context resulted in elevated concentrations of GluN2B subunits in the amygdala, hippocampus and the prefrontal cortex compared to LR rats as well as in the hippocampus and prefrontal cortex vs. the control group. In addition, it was shown that re-test of a conditioned fear increased the number of cells expressing GluN2B subunits in the basolateral amygdala, dentate gyrus of the hippocampus and secondary motor cortex (M2) in the HR group relative to the LR group. Together, these data suggest that animals that are more anxious have altered patterns of GluN2B subunit expression in the frontal cortex and limbic structures, which control emotional behaviour.

The effect of CRF2 receptor antagonists on rat conditioned fear responses and c-Fos and CRF expression in the brain limbic structures

The influence of intracerebroventricular-administered selective corticotropin-releasing factor receptor 2 (CRF(2)) antagonists (antisauvagine-30, astressin-2B), on rat anxiety-like behavior, expression levels of c-Fos and CRF, and plasma corticosterone levels were examined in the present study. In fear-conditioned animals, both CRF receptor antagonists enhanced a conditioned freezing fear response and increased the conditioned fear-elevated concentration of serum corticosterone. Exogenously administered antisauvagine-30 increased the aversive context-induced expression of c-Fos in the 1 and 2 areas of the cingulate cortex (Cg1, Cg2), the central amygdala (CeA) and parvocellular neurons of the paraventricular hypothalamic nucleus (pPVN), and it enhanced the effect of conditioned fear in the secondary motor cortex (M2) and medial amygdala (MeA). Immunocytochemistry demonstrated an increase in CRF expression in the Cg1, M2 areas of the cortex, and pPVN, and it revealed the effect of conditioned fear in the CeA 35 min after antisauvagine-30 administration and 10 min after the conditioned fear test. Furthermore, astressin-2B, another CRF(2) receptor antagonist, enhanced expression of c-Fos and CRF in the CeA and pPVN, and revealed the effect of conditioned fear in the Cg1. These data support a model in which an excess in CRF(1) receptor activation, combined with reduced CRF(2) receptor signaling, may contribute to stronger expression of anxiety-like responses.

The localization of brain sites of anxiogenic-like effects of urocortin-2

The influence of intracerebroventricullary-administered urocortin-2, a selective corticotropin-releasing factor receptor 2 (CRF(2)) agonist, on rat anxiety-like behaviour, the expression of c-Fos and CRF, and plasma corticosterone levels was examined in the present study. When applied to animals exposed to the conditioned fear-induced context, urocortin-2 enhanced a conditioned freezing fear response. Urocortin-2 also significantly decreased rat exploratory activity in the open field test. Exogenous urocortin-2 increased the conditioned fear-induced expression of c-Fos in the central amygdala (CeA), and parvocellular neurons of the paraventricular hypothalamic nucleus (pPVN), and revealed the effect of conditioned fear in the medial amygdala (MeA). In the fear-conditioned animals, immunocytochemistry showed an increase in the density of CRF-related immunoreactive complexes in the lateral septum (LS), 35min after urocortin-2 administration and 10min after the conditioned fear test, compared with saline-pretreated fear-conditioned animals. These data suggest a role of urocortin-2 in the behavioural and immunocytochemical responses to stress, in which it strengthens the measures of anxiety-like responses.

Role of autophagy in mammary gland development

Autophagy is a highly conserved catabolic process responsible for degradation and recycling of long-lived proteins and organelles by lysosomes. This degradative pathway, together with proteasome system is particularly important during development and under certain environmental stress conditions. This review summarizes the latest achievements of studies aiming to explore the role of autophagy in development and differentiation of eukaryotic cells. It shows the importance of this process in the development of lower eukaryotic organisms such as Dicyostelium discoideum, and Caenorhabditis elegans, as well as functions of autophagy and autophagy related genes (Atg) in development and differentiation of higher eukaryotic organisms. The review is focused on the results of studies conducted on mammary gland, as it is a good model for studying the mechanisms controlling higher eukaryotic organisms' development. Studies have shown that autophagy is involved in the removal of epithelial cells during formation of alveolar structures, indicating its role in mammogenesis. There are also evidences of involvement of Atg's in epithelial tumors development. Context dependent manipulations of autophagic pathways may create more effective anticancer therapies in the future.

[Nested PCR in the diagnosis of Pneumocystis carinii pneumonia (PCP) in AIDS patients]

The studies were undertaken to evaluate the usefulness of a nested PCR assay in the diagnosis of Pneumocystis carinii pneumonia (PCP) in AIDS patients. To achieve the end, 51 excretions samples from the respiratory tract were collected from HIV-infected patients with respiratory symptoms, and examined for the presence of specific DNA. A portion of the mitochondrial large-subunit rRNA gene of Pneumocystis carinii was amplified with outer primers pair pAZ 102E, pAZ 102H and internal primers pAZ 102X, pAZ 102Y. Positive nested PCR results were obtained with 36 out of 51 examined samples. Some 52.8% of the positive results were obtained with samples collected from patients without clinical diagnosis of PCP. It was concluded, that the nested PCR method, being too sensitive, is not suitable for the routine diagnosis of PCP in AIDS patients.

[An analysis of the course of experimental pneumocystosis in rats using some serological methods]

Since serological methods used in the diagnosis of pneumocystosis may be helpful to a various extent, depending on the stage of a diagnosed infection, it was decided to evaluate the usefulness of some the methods in the course of infection. Wistar rats were used in the experiments. The animals were administered hydrocortisone injections for 12 weeks to induce immunosuppression and activate naturally occurring asymptomatic infections with Pneumocystis carinii. Blood samples and specimes of lung tissues were collected, then they were examined for the presence of specific IgG and IgM antibodies, circulating antigen of Pneumocystsis carinii and circulating immune complexes using immunoenzymatic assays. The results of the above experiments indicated, that in an early stage of infection, the examinations of serum samples for circulating immune complexes were helpful, particularly for these with IgM antibodies