Transfer of orally administered ZnO:Eu nanoparticles through the blood-testis barrier: the effect on kinetic sperm parameters and apoptosis in mice testes

Zinc-based nanoparticles are promising materials for various applications, including in biomedicine. The aim of our study was to determine the effect of fluorescent europium-doped zinc oxide nanoparticles (ZnO:Eu NPs) on sperm parameters, cell apoptosis and integrity of the blood-testis barrier (BTB) in mice. Nanostructures were orally administered to adult mice (n = 34). Animals were sacrificed after 3 h, 24 h, 7 d and 14 d following oral administration. Sperm was collected and analysed for viability and kinetic parameters. Collected testes were quantitatively analysed for accumulation of ZnO:Eu NPs. Microscopic evaluation based on immunofluorescence and histopathological studies were also conducted. Results showed that ZnO:Eu NPs were able to overcome the BTB with their subsequent accumulation in the testis. No toxic or pro-apoptotic effects of nanoparticles on the male reproductive system were observed. The results suggested that ZnO:Eu NPs were able to accumulate in the testis with no negative impact on sperm parameters, tissue architecture or the integrity of the BTB.

Occludin controls HIV transcription in brain pericytes via regulation of SIRT-1 activation

HIV invades the brain early after infection; however, its interactions with the cells of the blood-brain barrier (BBB) remain poorly understood. Our goal was to evaluate the role of occludin, one of the tight junction proteins that regulate BBB functions in HIV infection of BBB pericytes. We provide evidence that occludin levels largely control the metabolic responses of human pericytes to HIV. Occludin in BBB pericytes decreased by 10% during the first 48 h after HIV infection, correlating with increased nuclear translocation of the gene repressor C-terminal-binding protein (CtBP)-1 and NFκB-p65 activation. These changes were associated with decreased expression and activation of the class III histone deacetylase sirtuin (SIRT)-1. Occludin levels recovered 96 h after infection, restoring SIRT-1 and reducing HIV transcription to 20% of its highest values. We characterized occludin biochemically as a novel NADH oxidase that controls the expression and activation of SIRT-1. The inverse correlation between occludin and HIV transcription was then replicated in human primary macrophages and differentiated monocytic U937 cells, in which occludin silencing resulted in 75 and 250% increased viral transcription, respectively. Our work shows that occludin has previously unsuspected metabolic properties and is a target of HIV infection, opening the possibility of designing novel pharmacological approaches to control HIV transcription.

192 EXPRESSION OF SELECTED ANTIOXIDANT ENZYMES IN BOVINE OVIDUCT EPITHELIAL CELL (BOEC) IN RESPONSE TO ELEVATED TEMPERATURES IN VITRO

Elevated temperatures have a negative impact on bovine reproduction. One of its effects is an increased concentration of reactive oxygen species (ROS) which may lead to female infertility. Oxidative stress impairs oocyte maturation, fertilization, and embryo development, and it also influences the reproductive tract. One of the defence mechanisms against the increase of ROS is the synthesis of antioxidants. Thus, the aim of this study was to analyse the expression of antioxidant enzymes (superoxide dismutase 1, SOD1; catalase, CAT; and glutathione peroxidase 1, GPX1) in bovine oviduct epithelial cells (BOEC) cultured with or without embryos at elevated temperatures. Ovaries and oviducts were collected from a slaughterhouse. BOECs were mechanically isolated from the oviducts. The oocytes were isolated from ovaries and then maturated and fertilized in vitro. BOEC, after formation of aggregates, were cultured (variant I) in 40-µL droplets of cultured medium (TCM199 25 mM HEPES medium supplemented with 10% FBS, 10 µg mL–1 gentamicin, and 50 µg mL–1 streptomycin) overlaid with mineral oil. Twenty aggregates per droplet were cultured at control (38.5°C) and elevated (41°C) temperatures for 168 h in 5% CO2 in air. Analogously, in variant II, BOEC aggregates were co-cultured with 15 bovine embryos per droplet. Subsequently, the SOD1, CAT, and GPX1 mRNA levels were analysed in BOEC by real-time RT–PCR (Light Cycler, Roche Diagnostics, Warsaw, Poland) and normalized to S18/H2A gene expression. Relative quantification was determined with LightCycler software version 3.5 (Roche Diagnostics) by the second derivative maximum method. Statistical analyses were performed by Portable Statgraphics 5.0 Centurion (Statpoint Technologies Inc., Warrenton, VA). Mean values of SOD1, CAT, and GPX1 expression in BOEC in RT-qPCR analysis were compared using Tukey's HSD test (a = 0.01). Elevated temperature leads to an up-regulation of SOD1 in BOEC cultured (38°C: 0.76 ± 0.12 a.u., n = 44; 41°C: 1.07 ± 0.21 a.u., n = 48) and co-cultured with bovine embryos (38°C: 0.71 ± 0.11 a.u., n = 36; 41°C: 1.04 ± 0.2 a.u., n = 36) and the difference was statistically significant (P < 0.01). The CAT gene expression in BOEC was constant in variant I (38°C: 0.56 ± 0.22 a.u., n = 56; 41°C: 0.58 ± 0.27 a.u., n = 56) and variant II (38°C: 0.48 ± 0.27 a.u., n = 32; 41°C: 0.59 ± 0.29 a.u., n = 24). Also, GPX1 gene expression in BOEC was constant in variant I (38°C: 0.66 ± 0.23 a.u., n = 60; 41°C: 0.61 ± 0.19 a.u., n = 56) and in variant II (38°C: 0.59 ± 0.19 a.u., n = 36; 41°C: 0.64 ± 0.22 a.u., n = 36). In conclusion, elevated temperature leads to an activation of the BOEC's defence mechanisms which are based on SOD1 expression, and which may protect cells against oxidative stress. Elevated temperature doesn't affect the cat and GPX1 expression in BOEC. The presence of embryos does not affect the expression of antioxidant enzymes in BOEC. Research was supported by COST DPN/DWM/MZ/5670/08/09.

167 THE EFFECT OF ELEVATED TEMPERATURE ON THE HEAT SHOCK PROTEIN 70 (HSP70) EXPRESSION IN BOVINE CUMULUS&ndash;OOCYTE COMPLEXES AFTER IN VITRO MATURATION

Elevated temperature during in vitro maturation negatively affects the oocyte's developmental competence, leading to disturbances in nuclear and cytoplasmic maturation. In previous studies, the role of cumulus granulosa cells (CGC) in cumulus-oocyte complexes' (COC) response to elevated temperature was underestimated. However, CGC play an essential role in folliculogenesis, supporting the oocyte's metabolism as well as meiotic progression. Thus, CGC may be engaged in COC response to heat shock. Heat shock protein 70 (HSP70) is the major protein engaged in cellular response to heat stress. The aim of this study was to determine the HSP70 expression in both CGC and oocytes in response to elevated temperature after COC in vitro maturation. COC were collected from bovine ovarian follicles (diameter 2–6 mm) from slaughtered cows and divided into two treatment groups: I (control) – COC were in vitro matured in control temperature (38.5°C); II (experimental) – COC were in vitro matured in elevated temperature (41°C). After in vitro maturation they were mechanically separated into CGC and oocyte. In vitro maturation was conducted in TCM199 25 mM HEPES medium supplemented with 10% FBS, 0.02 IU mL–1 NIH-pFSH, 1 μg mL–1 17β-oestradiol, 22 μg mL–1 Na-pyruvate and 10 μg mL–1 gentamicin, adjusted to pH 7.4 in 5% CO2. The HSP70 expression in CGC and oocytes was performed by real-time PCR and normalized to S18/H2A and S18 gene expression, respectively. In addition, the immunocytofluorescent analysis of HSP70 expression in CGC and oocyte's were performed. The HSP70 was stained using primary monoclonal mouse antibodies raised against bovine HSP70 and secondary antibody raised against mouse conjugated with Alexa 488. Nuclei were stained with Hoechst 33342. Slides were analysed under laser confocal microscope (FV-500, Olympus, Center Valley, PA, USA). The HSP70 expression in CGC was measured as total optical density of HSP70 and normalized to total optical density of nuclei. Statistical analyses were performed by Portable Statgraphics 5.0 Centurion. Mean values of HSP70 expression in CGC and oocytes in real-time PCR and immunofluorescent analysis in CGC were compared using Tukey's HSD test (α = 0.01). After in vitro maturation, the expression of HSP70 in CGC was higher (0.13 ± 0.052 a.u., n = 35) in experimental temperature compared to the control (0.058 ± 0.008 a.u., n = 35) (P < 0.01). In oocytes, HSP70 expression in experimental temperature (32.5 ± 5.2 a.u., n = 12) was similar to control (29.8 ± 5.6 a.u., n = 12). The immunofluorescent analysis confirmed data from real-time PCR analysis, indicating that the HSP70 expression in CGCs in experimental temperature was higher (0.46 ± 0.07 a.u., n = 10) compared to the control (0.12 ± 0.02 a.u., n = 10; P < 0.01). After COC in vitro maturation in stress conditions, the HSP70 expression was up-regulated in CGC, but not in oocytes. That may indicate that CGCs play the major role in COC response to elevated temperature; however, the analysis of other heat shock proteins expression in CGC and oocytes need to be conducted. Research was supported by 505-10-023300-K00169-99.

Redox-sensitive structure and function of the first extracellular loop of the cell-cell contact protein claudin-1: lessons from molecular structure to animals

The paracellular cleft within epithelia/endothelia is sealed by tight junction (TJ) proteins. Their extracellular loops (ECLs) are assumed to control paracellular permeability and are targets of pathogenes. We demonstrated that claudin-1 is crucial for paracellular tightening. Its ECL1 is essential for the sealing and contains two cysteines conserved throughout all claudins.

AIMS

We prove the hypothesis that this cysteine motif forms a redox-sensitive intramolecular disulfide bridge and, hence, the claudin-1-ECL1 constitutes a functional structure which is associated to ECLs of this and other TJ proteins.

RESULTS

The structure and function of claudin-1-ECL1 was elucidated by investigating sequences of this ECL as synthetic peptides, C1C2, and as recombinant proteins, and exhibited a β-sheet binding surface flanked by an α-helix. These sequences bound to different claudins, their ECL1, and peptides with nanomolar binding constants. C-terminally truncated C1C2 (-4aaC) opened cellular barriers and the perineurium. Recombinant ECL1 formed oligomers, and bound to claudin-1 expressing cells. Oligomerization and claudin association were abolished by reducing agents, indicating intraloop disulfide bridging and redox sensitivity.

INNOVATION

The structural and functional model based on our in vitro and in vivo investigations suggested that claudin-1-ECL1 constitutes a functional and ECL-binding β-sheet, stabilized by a shielded and redox-sensitive disulfide bond.

CONCLUSION

Since the β-sheet represents a consensus sequence of claudins and further junctional proteins, a general structural feature is implied. Therefore, our model is of general relevance for the TJ assembly in normal and pathological conditions. C1C2-4aaC is a new drug enhancer that is used to improve pharmacological treatment through tissue barriers.

173 THE IMPACT OF ELEVATED TEMPERATURE ON HSP70 EXPRESSION IN CATTLE MURAL GRANULOSA CELLS

Elevated temperature has an adverse impact on cattle fertility, causing disorders in ovarian functions and follicle development. Heat shock caused by elevated temperature leads to disruption in the cytoskeleton structure and the nuclear maturation of oocytes. Furthermore, it has an impact on mural granulosa cells (MGC), which are responsible for maintaining an appropriate microenvironment for oocyte development and signal transmission through the ovarian follicle. Heat-shock protein 70 is considered as a fundamental marker of cellular defence mechanisms related to heat shock. It protects other proteins from denaturation by forming complexes and stabilisation of their structure. HSP70 has also an ability to repair damaged proteins and allows them to return to their native structure. Furthermore, members of the HSP70 subfamily participate in the folding of newly synthesised proteins and their transport to different cell compartments. The aim of this study was to determine the impact of elevated temperature on HSP70 expression in mural granulosa cells. MGCs were obtained postmortem from mural layers of cattle ovarian follicles with diameters greater than 15 mm and randomly assigned to one of 5 variants: I (control) – MGCs after isolation; II – MGCs cultured in medium with LH at 38.5°C; III – MGCs cultured in medium with LH at elevated temperature, 41°C; IV – MGCs cultured in medium without LH at 38.5°C; and V – MGCs cultured in medium without LH at elevated temperature, 41°C. HSP70 expression was determined using real-time PCR method, and was normalised to s18/h2a expression. Statistical analysis was made in Statgraphics (Statpoint Technologies Inc., Warrenton, VA, USA; P = 0.01) using one-way ANOVA to compare expression of hsp70 between experimental variants and multifactor ANOVA to determine the influence of temperature and LH stimulation on hsp70 expression. Mean values of hsp70 expression in real-time PCR were compared using Tukey's test (a = 0.05). The significant increase of hsp70 expression was observed in MGCs cultured at 41°C (groups III and V) in comparison to MGCs cultured at 38.5°C (groups II and IV) and the control group. Simultaneously, there is no significant impact of LH stimulation on hsp70 expression. In conclusion, mural granulosa cells are susceptible to elevated temperature, which induces activation of cellular defence mechanisms performed by increased hsp70 expression. This may lead to disorders in the function of MGCs followed by changes in follicular fluid composition and signal transmission through the follicle. Research was supported by 505-10-023300-L00171-99.

258 THE PRELIMINARY RESULTS OF IN VITRO PRODUCTION OF THE WISENT HYBRID EMBRYOS

Wisent (Bison bonasus), also called the European bison, is listed as vulnerable on the International Union for the Conservation of Nature Red List of Threatened Species. In Poland, a program for protection in situ and ex situ is being implemented. One new approach is the use of the in vitro embryo production (IVP) procedures to obtain wisent offspring. In contrast to previous successes with cattle IVP, use of IVP with wisent is limited by the small size of the population (only ~5000 individuals in more than 200 herds in Europe) and seasonal reproduction. The aim of this preliminary study was to obtain hybrid embryos (Bison bonasus × Bos taurus) in vitro. Ovaries were isolated from wisent females outside the reproductive season and eliminated from breeding for reasons other than infertility. Cumulus-oocytes complexes (COC) were isolated from all follicles above 2 mm in diameter. All COC were matured in TCM 199 supplemented with 10% fetal bovine serum, 0.02 IU mL–1 of porcine FSH, 17 β-oestradiol, 0.2 mM Na pyruvate, and antibiotics. The COC were cultured for 24 h at 38.5°C and 5% CO2 in humidified air. The matured COC (Bison bonasus) were fertilized in vitro with sperm from Jersey bulls (Bos taurus) in TALP supplemented with 6 mg mL–1 of fatty acid free BSA (BSA FAF), 0.2 mM Na pyruvate, 20 µM penicillamine,10 µM hypotaurine, 1 µM epinephrine, 2 µg mL–1 heparin, and antibiotics. Spermatozoa were used at a final concentration of 1 × 105 per oocyte and were co-cultured for 18 h at 38.5°C and 5% CO2 in humidified air. The hybrid zygotes were cultured in KSOM supplemented with 5 µg mL–1 of MEM Nonessential Amino Acid Solution (100×), 3 mg mL–1 of BSA FAF, and antibiotic for 192 h at 38.5°C and 5% CO2 in humidified air. The medium was partly replaced by fresh medium after 48 and 144 h of culture. Development was evaluated every day. From 25 COC isolated from wisent ovaries, only 18 COC were qualified for in vitro maturation (60%). Of these, 15 COC (83.3%) matured. The percentage of hybrid embryos that cleaved was 80% after 48 h of culture, and the percentage of embryos that developed up to the 8-cell stage was 33% after 96 h of culture. The morula/blastocyst rate was 26.6% after 192 h of culture, as represented by 1 early blastocyst, 2 compact morulae, and 1 morula. The use of the cattle IVP procedure allowed to receive hybrid embryos (Bison bonasus × Bos taurus), but they developed slower than cattle embryos under the same conditions, based on our previous studies. This research will be continued and may make a contribution to the protection of this threatened species.

Highly conserved cysteines are involved in the oligomerization of occludin-redox dependency of the second extracellular loop

The tight junction (TJ) marker occludin is a 4-transmembrane domain (TMD) protein with unclear physiological and pathological functions, interacting with other TJ proteins. It oligomerizes and is redox sensitive. However, oligomerization sites and mechanisms are unknown.

AIMS

To identify hypoxia-sensitive binding sites, we investigated the consequences of amino-acid substitutions of highly conserved cysteines in human occludin, under normal and hypoxic incubations.

RESULTS

(i) The extracellular loop 2 (ECL2) showed homophilic trans- and cis-association between opposing cells and along the cell membrane, respectively, caused by a loop properly folded via an intraloop disulfide bridge between the shielded C216 and C237. Hypoxia and reductants prevented the associations. (ii) C82 in TMD1 directly cis-associated without disulfide formation. (iii) C76 in TMD1 and C148 in TMD2 limited the trans-interaction; C76 also limited occludin-related paracellular tightness and changed the strand morphology of claudin-1. (iv) The diminished binding strength found after substituting C82, C216, or C237 was accompanied by increased occludin mobility in the cell membrane.

INNOVATION

The data enable the first experimentally proven structural model of occludin and its homophilic interaction sites, in which the ECL2, via intraloop disulfide formation, has a central role in occludin's hypoxia-sensitive oligomerization and to regulate the structure of TJs.

CONCLUSION

Our findings support the new concept that occludin acts as a hypoxiasensor and contributes toward regulating the TJ assembly redox dependently. This is of pathogenic relevance for tissue barrier injury with reducing conditions. The ECL2 disulfide might be a model for four TMD proteins in TJs with two conserved cysteines in an ECL.

Association between segments of zonula occludens proteins: live-cell FRET and mass spectrometric analysis

The tight junction protein ZO-1 (zonula occludens protein 1) has recruiting/scaffolding functions in the junctional complex of epithelial and endothelial cells. Homodimerization was proposed to be crucial for ZO-1 function. Here, we investigated the ability of ZO-1 domains to mediate self-interaction in living cells. We expressed ZO-1 truncation mutants as fusions with derivatives of green fluorescent protein in tight junction-free HEK-293 cells and determined self-association by means of fluorescence resonance energy transfer measurements using live-cell imaging. We show that both an SH3-hinge-GuK fusion protein and the PDZ2 domain self-associate in our test system. The recombinant PDZ2 domain also binds to ZO-1 and ZO-2 in tight junction-forming HT29/B6 cell lysates, as demonstrated by coprecipitation. Both interaction types are of relevance for the function of ZO-1 in the regulation of the junctional complex in polar cells.

[Primary pulmonary hypertension in pregnancy--a case report]

Primary pulmonary arterial hypertension, so called idiopathic pulmonary arterial hypertension (IPAH), is a rare and progressive disease with poor prognosis. Pregnancy in patients with this condition is hazardous and makes the prognosis significantly worse. According to WHO, IPAH is a contraindication to pregnancy because of high risk of maternal death and WHO advises to discuss termination in the event of pregnancy Below we describe a case of a young woman at 16 weeks pregnancy with severe decompensated primary pulmonary hypertension. The patient was admitted to our department because of increasing dyspnoea and swollen legs occurring from 14th week of pregnancy. In the past the patient had been diagnosed with pulmonary hypertension, which had been defined during differential diagnostics as primary pulmonary hypertension. Echocardiographic examination over the last 4 years revealed stable mean pulmonary artery pressure (PAP) of about 50 mmHg. The patient was treated efficiently with sildenafil for the last 2 years, but the therapy was discontinued after finding pregnancy. On admission it was established that pregnancy should be terminated. Other reasons of circulatory decompensation, such as pulmonary embolism, cardiac tamponade or pulmonary diseases, were excluded.

[Cardiopulmonary resuscitation in pregnancy--European Resuscitation Council guidelines]

Cardio-pulmonary resuscitation is a life-saving technique that should be familiar to all people, even those without medical education. There are two basic life-saving levels: BLS (Basic Life Support) and ALS (Advanced Life Support). ALS a medical procedure that is restricted to medical practitioners. Cessation of circulation may happen to anyone. Cardiac arrest in case of pregnant women is a very specific state. The cause of life-threatening states during pregnancy can be connected with new infections, exacerbation of chronic diseases, as well as changes connected with the pregnancy itself. In those situations, due to physiological and anatomical changes which occur during pregnancy some modifications in the procedure of resuscitation are necessary

Polymorphism of VDR gene--the most effective molecular marker of osteoporotic bone fractures risk within postmenopausal women from Wielkopolska region of Poland

The major public health problem which will arise is a frequency of osteoporosis. The first manifestations of this disease are often bone fractures. Identification and evaluation of individual bone fracture risk will be the most effective way of solving the problem. Genetic determination of osteoporosis is unquestionable. The aim of this study is to detect which variants of genotypes lead to illness. We investigated 187 patients with osteoporosis (161 women, 26 men) and 19 healthy subjects. Polymorphisms of the following genes were investigated: OPG, VDR, ESR1, TGFB1 COL1A1, and BMP2. The statistically significant relationship between BMD value and T allele of Taq I VDR gene were found. Genotypes: aa, bb, TT of VDR gene occur more frequently in polish osteoporotic population in Wielkopolska region within patients with higher risk of bone fractures.

Anaerobic digestion of manure and mixture of manure with lipids: biogas reactor performance and microbial community analysis

Anaerobic digestion of cattle manure and a mixture of cattle manure with glycerol trioleate (GTO) was studied in lab-scale, continuously stirred tank reactors (CSTR) operated at 37 degrees C. The reactor codigesting manure and lipids exhibited a significantly higher specific methane yield and a higher removal of VS than the reactor treating manure. Microbial population analysis done by cultivation--most probable number (MPN) test and specific methanogenic activity (SMA) measurement, revealed higher MPN and increased SMA of methanogenic populations of biomass from the reactor codigesting manure and lipids. Spatial microbial distribution and activity was studied in digested materials fractionated into size of particles > 200 microm, 50-200 microm and 0.45-50 microm. With manure, the main pool of methanogenic activity from propionate, butyrate and hydrogen was associated with the particles > 200 microm, while the activity of acetotrophic methanogens was uniformly distributed in all fractions. When digesting manure and lipids, an enhanced methanogenesis was detected both for particles > 200 microm and the 50-200 microm fraction. The molecular methods--temperature gradient gel electrophoresis (TGGE), cloning library and sequencing of 16S rDNA--showed presence of a restricted number of archaeal species in both reactors. The vast majority of clones was phylogenetically most closely related to Methanosarcina siciliae.

Function of insulin-like growth factor (IGF-I) and its binding protein (IGFBP-1) in pathological proliferation of endometrium

The purpose of this project was the investigation of insulin, IGF-I and IGFBP-1 concentrations in the serum of patients with pathological changes in endometrium. IGF-I and its binding protein (IGFBP-1) stimulate cell growth and differentiation of the normal and neoplastic endometrium. The mean values of IGF-I concentrations in the group of patients with atypical hyperplasia and endometrial carcinoma were significantly higher than in the control group with normal endometrium. Significantly higher IGFBP-1 concentrations were found in the serum of patients with the atypical hyperplasia of endometrium and endometrial carcinoma. The correlation between insulin concentration and changes in endometrium in the examined groups was not found.

Fluorescent protein vector for directional selection of PCR clones

Green fluorescent protein (GFP) has become a convenient and versatile tool as a reporter protein in many aspects of science. Here, we show that the enhanced yellow fluorescent protein (EYFP) variant may be used advantageously as a reporter system for directional cloning of blunt-ended PCR products. We have constructed a pUC18-derived plasmid containing a reporter gene coding EYFP cloned into the BamHI/HindIII sites. The blunt-ended PCR product is cloned into the SmaI site of that plasmid. A reverse PCR primer must be designed with extra bases on the 5' end that are required to introduce a ribosome binding site (rbs) for EYFP expression. The reporter gene coding EYFP is not expressed unless an rbs is introduced in the proper orientation at the 3' end of the cloned PCR insert. The results of this cloning procedure may be analyzed by simple visual inspection using a transilluminator. In most cases, successful directional cloning results in white fluorescent colonies. The proposed procedure is a convenient method that can reduce the time- and labor-intensive analysis of the clones obtained during blunt-ended PCR product cloning.

[Laparotomy performed in pregnant women due to non-obstetrical causes]

OBJECTIVE

The clinical characteristics of laparotomy during pregnancy were investigated.

MATERIALS AND METHODS

A series of 24 cases of laparotomy during pregnancy was investigated with respect to clinicopathologic features and outcome.

RESULTS

Among 23 cases there were 20 ovarian tumors, 2 acute appendicitis and 2 uterine fibroid. Gestational ages at the time of surgery ranged from 16 to 24 weeks of patients with ovarian tumors and from 30 to 32 weeks in others. No intraoperative or postoperative maternal or fetal complications occurred. One patient had a stage III ovarian carcinoma and went to total hysterectomy, and other patient had a stage IA ovarian carcinoma.

CONCLUSIONS

Appendectomy can be performed without additional risk to the fetus for those who require surgical intervention during pregnancy. Ovarian surgery in pregnancy for persistent masses is important to obtain a final histologic diagnosis.

Protection of cattle against bovine leukemia virus (BLV) infection could be attained by DNA vaccination

The bovine leukemia virus (BLV) envelope gene encoding extracellular glycoprotein gp51 and transmembrane glycoprotein gp30 was cloned into a vehicle expression vector under the human cytomegalovirus (CMV) intermediate early promoter. The intramuscular injection of this plasmid vector generated a cellular immune response. Seven out of ten cows vaccinated with the DNA construct resisted a drastic challenge (500 BLV-infected lymphocytes as an infectious dose).

Protection of cattle against bovine leukemia virus (BLV) infection could be attained by DNA vaccination

The bovine leukemia virus (BLV) envelope gene encoding extracellular glycoprotein gp51 and transmembrane glycoprotein gp30 was cloned into a vehicle expression vector under the human cytomegalovirus (CMV) intermediate early promoter. The intramuscular injection of this plasmid vector generated a cellular immune response. Seven out of ten cows vaccinated with the DNA construct resisted a drastic challenge (500 BLV-infected lymphocytes as an infectious dose).

Cloning, overexpression, and purification of the recombinant His-tagged SSB protein of Escherichia coli and use in polymerase chain reaction amplification

Polymerase chain reaction (PCR)-derived DNA fragment containing the complete structural gene for SSB protein of the Escherichia coli was cloned into an expression vector. The clones expressing His-tagged SSB protein were selected. The cloned DNA fragments were verified to be authentic by sequencing several clones. The recombinant SSB protein (His-tagged SSB) contained a polyhistidine tag at the N-terminus (38 additional amino acids) that allowed single-step isolation by Ni2+ affinity chromatography. We found that recombinant plasmids are unstable and give a low level of expression in E. coli BL21(DE3) strain. However, the plasmids were stable in E. coli BL21(DE3) containing the pLysS plasmid, which suppresses expression prior to induction, and His-tagged proteins were highly expressed upon IPTG addition. The SSB protein was purified by metal-affinity chromatography on Ni2+-TED-Sepharose columns. The enzyme was characterized by fluorescence titration experiments for single-stranded DNA binding activity. We have applied the use of His-tagged SSB protein to increase amplification efficiency with a number of diverse templates. The use of SSB protein may prove to be generally applicable in improving PCR efficiency.

Recombinant His-tagged DNA polymerase. I. Cloning, purification and partial characterization of Thermus thermophilus recombinant DNA polymerase

The Tth DNA polymerase gene from the thermophilic Thermus thermophilus (strain HB8) was amplified, cloned and expressed in Escherichia coli. The recombinant DNA polymerase containing a polyhistidine tag at the N-terminus was isolated in a single step by Ni2+ affinity chromatography. The purified recombinant enzyme, showing high polymerase activity contained 43 additional amino-acid residues (including a cluster of six histidine residues inserted for purification of the recombinant protein by metal-affinity chromatography) at N-terminus. The applied overexpression system was very efficient giving 700,000 u of DNA polymerase activity from 1 liter of induced culture. The enzyme was characterized and displayed high DNA polymerase and reverse transcriptase activities and high thermostability as compared to the native Tth DNA polymerase.

Recombinant His-tagged DNA polymerase. II. Cloning and purification of Thermus aquaticus recombinant DNA polymerase (Stoffel fragment)

The Stoffel DNA fragment, shortened by 12 bp from 5' end, coding for Stoffel DNA polymerase (missing 4 amino acids at N-terminus of Stoffel amino-acids sequence) from the thermophilic Thermus aquaticus (strain YT-1) was amplified, cloned and expressed in Escherichia coli. The recombinant Stoffel fragment contained a polyhistidine tag at the N-terminus (21 additional amino acids) that allowed its single-step isolation by Ni2+ affinity chromatography. The enzyme was characterized and displayed high DNA polymerase activity and thermostability evidently higher than the native Taq DNA polymerase.

Cloning and nucleotide sequence of the thermostable beta-galactosidase gene from Pyrococcus woesei in Escherichia coli and some properties of the isolated enzyme

Pyrococcus woesei (DSM 3773) beta-galactosidase gene amplified by polymerase chain reaction was cloned into KpnI and HindIII binding sites of pET-30LIC expression plasmid. The obtained pGal2 (6785 bp) transcription vector was then transferred to Escherichia coli B121 (DE3) cells. High identity (99.9%) of DNA sequences suggests that beta-galactosidases from P. woesei and Pyrococcus furiosus are closely related. This enzyme from E. coli transformant is a unique thermostable protein in the cells and can be successfully separated by thermal precipitation of other bacterial proteins at 85 degrees C. The crude beta-galactosidase remaining in the solution comprises about 21% of the total amount of proteins extracted from E. coli cells and has maximal activity at pH 5.4 and temperature of 93 degrees C. Isolated enzyme is active at temperatures up to 110 degrees C and the activity loss after 4 h of incubation at 85 and 93 degrees C did not exceed 11 and 15% of the initial value respectively.

Cloning and expression in Escherichia coli of the recombinant his-tagged DNA polymerases from Pyrococcus furiosus and Pyrococcus woesei

Complete PCR-derived DNA fragments containing the structural genes for DNA polymerases of the archaeons Pyrococcus furiosus and Pyrococcus woesei were cloned into an expression vector. The clones expressing thermostable His-tagged DNA polymerases were selected. The cloned fragments were sequenced. The DNA sequences were verified to be authentic by sequencing several clones. The nucleotide (nt) sequence revealed that DNA polymerase of P. woesei (Pwo DNA polymerase) consists of 775 amino acids and has a molecular weight of 90,566. It shows 100% nucleotide identity to the nucleotide sequence of DNA polymerase from P. furiosus (Pfu DNA polymerase). The results confirm that nucleotide sequences of both archaeons (P. furiosus and P. woesei) are highly similar. The recombinant DNA polymerases (His-tagged Pfu and His-tagged Pwo) contained a polyhistidine tag at the N-terminus (43 additional amino acids) that allowed single-step isolation by Ni-affinity chromatography. We found that recombinant plasmids are toxic or unstable in the expressing strain BL21(DE3), even in the absence of the inducing agent, IPTG. However, the plasmids were stable in BL21(DE3) containing the pLysS plasmid, which suppresses expression prior to induction, and His-tagged proteins were expressed upon IPTG addition. The proteins were purified by heat treatment (to denature E. coli proteins), followed by metal-affinity chromatography on Ni2+-Sepharose columns. The enzymes were characterized and displayed high DNA polymerase activity and thermostability. This bacterial expression system appears to be the method of choice for production of Pfu or Pwo DNA polymerases.

Recombinant His-tagged DNA polymerase. I. Cloning, purification and partial characterization of Thermus thermophilus recombinant DNA polymerase

The Tth DNA polymerase gene from the thermophilic Thermus thermophilus (strain HB8) was amplified, cloned and expressed in Escherichia coli. The recombinant DNA polymerase containing a polyhistidine tag at the N-terminus was isolated in a single step by Ni2+ affinity chromatography. The purified recombinant enzyme, showing high polymerase activity contained 43 additional amino-acid residues (including a cluster of six histidine residues inserted for purification of the recombinant protein by metal-affinity chromatography) at N-terminus. The applied overexpression system was very efficient giving 700,000 u of DNA polymerase activity from 1 liter of induced culture. The enzyme was characterized and displayed high DNA polymerase and reverse transcriptase activities and high thermostability as compared to the native Tth DNA polymerase.

Recombinant His-tagged DNA polymerase. II. Cloning and purification of Thermus aquaticus recombinant DNA polymerase (Stoffel fragment)

The Stoffel DNA fragment, shortened by 12 bp from 5' end, coding for Stoffel DNA polymerase (missing 4 amino acids at N-terminus of Stoffel amino-acids sequence) from the thermophilic Thermus aquaticus (strain YT-1) was amplified, cloned and expressed in Escherichia coli. The recombinant Stoffel fragment contained a polyhistidine tag at the N-terminus (21 additional amino acids) that allowed its single-step isolation by Ni2+ affinity chromatography. The enzyme was characterized and displayed high DNA polymerase activity and thermostability evidently higher than the native Taq DNA polymerase.

[Community self-help houses as a form of community social support]

Two forms of community-based social support were introduced by the Polish Mental Health Act--community specialist social help services and community self-help houses--for seriously mentally ill and severely mentally retarded persons. According to the art. 8 community social support should be organized by social help agencies in consultation with psychiatric facilities. Data obtained from the Ministry of Labour and Social Policy indicated that from 21th of January 1995 (when the Mental Health Act was put in force) until 30th of June 1997 social help agencies and non-governmental organizations sponsored by social help agencies have set up 134 community self-help houses with 4103 places. In the middle of last year nearly 3500 persons were using these houses. Most of the houses were located in the following districts: Gdańsk (20), Gorzów (16), Płock (12), Warszawa (8 for 164 persons). Vast majority of them served as day rehabilitation houses, while only a few provided sheltered housing as well. Tentative evaluation of functioning of these houses shows that: operational definition of community self-help house given in the target network of nursing homes and community self-help houses should be modified to include statutory purposes of community social support provided in art.8, selection of the persons using community self-help houses should follow the legal requirement of the Mental Health Act (art. 8), separated rehabilitation programs for mentally ill (psychotic) and mentally retarded persons need to be provided, participation of psychiatric facilities in the organization of the community self-help houses should be increased, functioning of the community self-help houses ought to be supervised by specialists, staff of the community self-help houses need to be systematically trained.

[Specialist community social services as a form of community social support]

Art. 9 of the Polish Mental Health Act provides two forms of community-based social support--specialist social help services and community self-help houses for persons who, due a to serious mental illness or severe mental retardation, face considerable difficulties in their daily life, especially with respect to interpersonal relations, employment and welfare matters. The first form could only be implemented after coming into force of the suitable regulation of the Ministry of Labour and Social Policy of December 18, 1996 (Dz. U. z 1997 r., nr. 2, poz. 12). Hence, it may be understood that information on these services is exceptionally scarce. The author presents: a draft of legal evolution of the specialist services, from the vague idea of "community care" provided by psychiatric care facilities to the present regulation of community specialist social help services run by social help agencies in consultation with psychiatric facilities, main guidelines for staff to be observed in performing community specialist social help services (training in maintenance and development of basic skills necessary to independent living and others), the first promising experiences of a team rendering community specialist social help services in one of the communes in Warsaw.

[Decentralization of psychiatric health service]

The article discusses two stages of de-centralization of psychiatric hospitals: the first consists in further division into sub-districts, the second one includes successive establishment of psychiatric wards in general hospitals. With the growth of their number these wards are to take over more and more general psychiatric tasks from the specialized psychiatric hospitals. These wards will not substitute psychiatric hospitals completely. The hospitals, though decreasing in size and number, will be a necessary element of the de-centralized and versatile psychiatric care for a long time to come.

[Assessment of threatening behaviors in patients admitted to mental hospital]

Imminent threat presented by patients admitted to mental hospital was studied. The research data came from a questionnaire filled out by psychiatrists on duty at the time of admission. The study was carried out during 3 months in seven mental hospitals. It concerns only 1001 patients assessed by psychiatrists as imminently threatening. These assessments were compared with Lessard's criteria of dangerousness. Two types of assessments were made; type A--consistent with Lessard and type B not-consistent. Results obtained indicate that every third assessment belonged to type B i.e. could be seen as imminently threatening. Our findings show that psychiatrists taking part in the study were inclined to unduly broad or unduly discretional assessment of imminent threat.

Treatment, care, and rehabilitation of the chronic mentally ill in Poland

In Poland primary health settings provide about 71 percent of mental health services, particularly to patients with less serious illnesses, while psychiatry provides specialized mental health care for the chronic mentally ill, the mentally retarded, and patients with alcohol or drug dependence. Poland has a large number of outpatient clinics and an extensive network of sheltered workshops. Most inpatient psychiatric beds are located in mental hospitals; few general hospitals have psychiatric units. Deinstitutionalization has been less extensive in Poland than in many other countries; only about 10 percent of the chronic patients treated in mental hospitals were deinstitutionalized between 1970 and 1981. During that period the proportion of patients hospitalized for a year or more decreased, the number of chronic patients treated in nursing homes increased, and the pattern of hospitalization shifted toward multiple readmissions.

[Treatment of acute leukemias in adults. IV. Treatment results on 375 patients at 9 hematology centers]

On the basis of standardized protocols of the therapeutic results of acute non-lymphoblastic leukaemias in adults sent to the Institute of Haematology in Warsaw from 8 haematological centres in Poland it was demonstrated that complete remission occurred in 34.4% of patients (129 out of 375 cases). The mean survival time of the patients treated intensively according to programmes I, II, III and IV 8.6 months, those of patients with complete remission - 13.5 months, patients without complete remission - 3.7 months. The most frequent cause of death (82.5%) were infections and/or haemarrhagic diathesis.

The adductor transfer in the high-risk hip in myelodysplasia: a preliminary report

Hip instability occurs in meningomyelocele patients with lumbar level paralysis because of muscle imbalance. Transferring the hip adductor origins to the ischium can be used as the primary procedure to restore muscle balance and prevent hip instability in myelodysplasia patients if performed by the age of one year. Twelve lumbar meningomyelocele patients underwent bilateral adductor transfers. Secondary procedures, such as iliopsoas release or transfer or varus derotation osteotomy, were done in 14 hips. Ten hips needed no further surgery. Twenty of 24 hips were clinically and roentgenographically stable and showed roentgenographic evidence of improving hip development. Instability was associated with scoliosis, congenital dislocation, and age greater than one year at the time of the transfer.