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1.
Mon Not R Astron Soc ; 457(4): 4089-4113, 2016 Apr 21.
Article in English | MEDLINE | ID: mdl-32848283

ABSTRACT

We present a statistical analysis of the first four seasons from a "second-generation" microlensing survey for extrasolar planets, consisting of near-continuous time coverage of 8 deg2 of the Galactic bulge by the OGLE, MOA, and Wise microlensing surveys. During this period, 224 microlensing events were observed by all three groups. Over 12% of the events showed a deviation from single-lens microlensing, and for ~1/3 of those the anomaly is likely caused by a planetary companion. For each of the 224 events we have performed numerical ray-tracing simulations to calculate the detection efficiency of possible companions as a function of companion-to-host mass ratio and separation. Accounting for the detection efficiency, we find that 55 - 22 + 34 % of microlensed stars host a snowline planet. Moreover, we find that Neptunes-mass planets are ~ 10 times more common than Jupiter-mass planets. The companion-to-host mass ratio distribution shows a deficit at q ~ 10-2, separating the distribution into two companion populations, analogous to the stellar-companion and planet populations, seen in radial-velocity surveys around solar-like stars. Our survey, however, which probes mainly lower-mass stars, suggests a minimum in the distribution in the super-Jupiter mass range, and a relatively high occurrence of brown-dwarf companions.

2.
Nature ; 527(7579): 484-7, 2015 Nov 26.
Article in English | MEDLINE | ID: mdl-26560034

ABSTRACT

The first stars are predicted to have formed within 200 million years after the Big Bang, initiating the cosmic dawn. A true first star has not yet been discovered, although stars with tiny amounts of elements heavier than helium ('metals') have been found in the outer regions ('halo') of the Milky Way. The first stars and their immediate successors should, however, preferentially be found today in the central regions ('bulges') of galaxies, because they formed in the largest over-densities that grew gravitationally with time. The Milky Way bulge underwent a rapid chemical enrichment during the first 1-2 billion years, leading to a dearth of early, metal-poor stars. Here we report observations of extremely metal-poor stars in the Milky Way bulge, including one star with an iron abundance about 10,000 times lower than the solar value without noticeable carbon enhancement. We confirm that most of the metal-poor bulge stars are on tight orbits around the Galactic Centre, rather than being halo stars passing through the bulge, as expected for stars formed at redshifts greater than 15. Their chemical compositions are in general similar to typical halo stars of the same metallicity although intriguing differences exist, including lower abundances of carbon.

3.
Science ; 345(6192): 46-9, 2014 Jul 04.
Article in English | MEDLINE | ID: mdl-24994642

ABSTRACT

Using gravitational microlensing, we detected a cold terrestrial planet orbiting one member of a binary star system. The planet has low mass (twice Earth's) and lies projected at ~0.8 astronomical units (AU) from its host star, about the distance between Earth and the Sun. However, the planet's temperature is much lower, <60 Kelvin, because the host star is only 0.10 to 0.15 solar masses and therefore more than 400 times less luminous than the Sun. The host itself orbits a slightly more massive companion with projected separation of 10 to 15 AU. This detection is consistent with such systems being very common. Straightforward modification of current microlensing search strategies could increase sensitivity to planets in binary systems. With more detections, such binary-star planetary systems could constrain models of planet formation and evolution.

4.
Brain Inj ; 19(5): 365-9, 2005 May.
Article in English | MEDLINE | ID: mdl-16094784

ABSTRACT

Typically behaviour management plans attempt to change behaviour by manipulating the environmental consequences of selected behaviour. However, identifying the antecedent events that precede behaviour has also been demonstrated to be an important component of effective behaviour change programmes. The present case presentation attempts to demonstrate how antecedent procedures could be used to effectively manage behaviour problems in individuals with brain injury. Visual inspection of changes in the frequency of physical aggression and self-injurious behaviour of a child with brain injury provides preliminary data supporting the use of an intervention package of antecedent and consequence-based procedures. Clinical implications, limitations and possibilities for future research of antecedent control procedures are discussed.


Subject(s)
Behavior Therapy/methods , Brain Injuries/complications , Child Behavior Disorders/therapy , Aggression/psychology , Brain Injuries/psychology , Brain Injuries/rehabilitation , Child , Child Behavior Disorders/etiology , Child Behavior Disorders/psychology , Humans , Joints/physiopathology , Male , Physical Therapy Modalities , Proprioception/physiology , Self-Injurious Behavior/etiology , Self-Injurious Behavior/psychology , Self-Injurious Behavior/therapy , Social Environment , Treatment Outcome
5.
Folia Histochem Cytobiol ; 40(2): 163-4, 2002.
Article in English | MEDLINE | ID: mdl-12056626

ABSTRACT

The cells with nuclear DNA fragmentation related to apoptosis were detected by TUNEL technique in the seminiferous epithelium of control rats and of rats with experimental hyperprolactinemia induced by metoclopramide. The percentage of convoluted tubules with apoptotic cells and the number of apoptotic cells (predominantly spermatogonia and spermatocytes) was increased in the experimental group. The results indicated stage-specific germ cell apoptosis. In the experimental group, apoptotic cells were most evident at early (I-IV), middle (VII-VIII) and late (XII-XIV) stages of the seminiferous epithelium cycle, as revealed by light and electron microscopy. We suggest that a decreased concentration of testosterone and an increased concentration of prolactin could disturb spermatogenesis and contribute to the intensive apoptosis of germ cells in rats with hyperprolactinemia. Sertoli cells which have receptors for testosterone and prolactin and play an important role in spermatogenesis and in the initiation of apoptosis in seminiferous epithelium, could mediate such an influence of both hormones.


Subject(s)
Apoptosis/physiology , Cell Nucleus/pathology , DNA Fragmentation/physiology , Dopamine Antagonists , Germ Cells/pathology , Hyperprolactinemia/pathology , Metoclopramide , Testis/pathology , Animals , Cell Nucleus/ultrastructure , Germ Cells/ultrastructure , Hyperprolactinemia/chemically induced , Immunohistochemistry , In Situ Nick-End Labeling , Male , Microscopy, Electron , Rats , Rats, Wistar , Testis/ultrastructure , Tissue Fixation
6.
Int J Occup Saf Ergon ; 7(1): 35-47, 2001.
Article in English | MEDLINE | ID: mdl-11276263

ABSTRACT

Metabolic and toxicodynamic interactions of some organic solvents in rats repeatedly treated with medium dose levels were examined. It was shown that both n-hexane and ethylbenzene significantly inhibited tetrachloroethylene metabolism during a 2-week period. n-Hexane and tetrachloroethylene enhanced metabolism of ethylbenzene whereas ethylbenzene suppressed n-hexane metabolism only at the end of the experiment. Biochemical changes, especially the drop in the level of non-protein sulfhydryl groups in tissues of rats treated with organic solvent mixtures, were significantly less pronounced than those observed after these chemicals were administered separately. These results demonstrate that metabolic interactions between hydrocarbons and chloroalkene may lead to a modification of the biological response to these compounds.


Subject(s)
Benzene Derivatives/metabolism , Hexanes/metabolism , Solvents/toxicity , Tetrachloroethylene/metabolism , Animals , Benzene Derivatives/toxicity , Hexanes/toxicity , Male , Poland , Rats , Rats, Wistar , Tetrachloroethylene/toxicity
7.
Int J Occup Saf Ergon ; Spec No: 103-9, 2000.
Article in English | MEDLINE | ID: mdl-10828156

ABSTRACT

According to the Polish Labour Code &elpar;Ustawa, 1974) employers are legally obligated to provide workers with information about occupational health and safety risks. Maximum allowable concentrations (MAC) and the results of determining chemical compounds in workplace air are used for assessing occupational exposure and risk. A computer-assisted system STER, developed in the Central Institute for Labour Protection, helps to register and document occupational risk assessment and all actions resulting from those assessments.


Subject(s)
Air Pollutants, Occupational , Occupational Exposure , Risk Assessment , Computer Systems , Humans , Maximum Allowable Concentration , Poland
8.
Ann Acad Med Stetin ; 46: 63-75, 2000.
Article in Polish | MEDLINE | ID: mdl-11712318

ABSTRACT

Excessive activation of macrophages is considered to be the etiological factor of marital infertility. Peritoneal macrophages participate in the phagocytosis of menstrual detritus and sperm in the peritoneal cavity. Iron ingested by peritoneal macrophages could be responsible for their increased spermiophagy. This mechanism would operate in some gynecological diseases, particularly in endometriosis when the ectopic location of endometrial tissue in the pelvic cavity or oviduct becomes a source of cyclic menorrhagia into the peritoneal fluid. The aim of this study was to establish the effect of iron (Jectofer, Astra D, complex salt of Fe+3; 50 micrograms Fe+3/ml) on the morphology and phagocytic activity of LPS-activated peritoneal macrophages. Macrophages were cultured with iron in the presence or absence of iron chelator--Desferal (DFO) (Sigma; 500 micrograms/ml), using the method of Nechala and Hrudka [20]. The viability of cells was evaluated with the trypan blue exclusion test. Cells were washed twice, suspended in modified Dulbecco's medium, supplemented with 2% inactivated fetal calf serum and antibiotics, than transferred (1 x 10(6)) into a culture dish. Nonadherent cells were removed by repeated washing after 1 h incubation at 37 degrees C and 5% CO2. Macrophages were cultured in 1 ml medium with LPS (1 microgram/ml). After 2 or 24 h the macrophages were covered with the same number of rat epididymal sperm cells. Following 1.5 h of incubation, phagocytosis was assessed on the basis of the spermiophagic index (SPI). After 3.5 h of culture macrophages formed monolayers and groups of cells with intersecting sperm tails (Fig. 2). Increased sperm phagocytosis was observed in the macrophage culture exposed to iron for 3.5 h. SPI was significantly higher compared to control value (Fig. 1). The findings were confirmed with scanning and transmission electron microscopy. Macrophages cultured with iron for 3.5 h displayed features of activation, growing to considerable size and developing numerous elongated processes with which they surrounded spermatozoa. The cytoplasm was replete with endosomes containing spermatozoa (Fig. 3). Electron-dense structures could be seen in phagolysosomes. The presence of iron in these structures was confirmed by X-ray microanalysis (Fig. 6). In comparison, macrophages cultured in the presence of iron and iron chelator demonstrated diminished phagocytic activity (Fig. 1). After 24 h of culture macrophages formed cluster-like structures. Spermiophagy was still taking place outside such aggregates and macrophages had a normal appearance (Fig. 4). When iron was added to such culture very few macrophages and spermatozoa could be seen in the electron microscope (Fig. 5A). Iron-loaded macrophages underwent necrosis, their nucleus, plasma membrane and organelles displayed features of degeneration (Fig. 5B). SPI of macrophages exposed to iron for 24 h was significantly decreased as compared with control value (Fig. 1). The ultrastructure of macrophages exposed for 24 h to DFO only was not altered and the phagocytic activity was comparatively higher (Fig. 1). There was a great number of macrophages and spermatozoa forming giant aggregations. The present results suggest that iron enhances spermiophagy in 3.5 h culture. As phagocytic activity of macrophages was reduced by Desferal in 3.5 h culture, an iron chelator could be beneficial in endometriosis to reduce the iron content in the peritoneal cavity where a regular influx of new macrophages takes place.


Subject(s)
Iron/pharmacology , Macrophage Activation/drug effects , Phagocytosis/drug effects , Spermatozoa/metabolism , Animals , Cells, Cultured , Cytoplasm/chemistry , Cytoplasm/pathology , Female , Iron/analysis , Macrophages, Peritoneal/metabolism , Macrophages, Peritoneal/pathology , Male , Rats , Rats, Wistar , Spermatozoa/drug effects , Spermatozoa/pathology
9.
J Exp Zool ; 283(3): 242-57, 1999 Feb 15.
Article in English | MEDLINE | ID: mdl-9933937

ABSTRACT

Brush border myosin-I is a class I myosin with calmodulin light chains that has been identified in several vertebrate species. In chicken, it is exclusively expressed in intestinal epithelial cells where it forms spirally arrayed bridges that tether the microvillar actin bundle to the membrane. To facilitate future knockout strategies, we have isolated mouse brush border myosin-I cDNA and genomic clones. The deduced primary structure of mouse brush border myosin-I is homologous to other known brush border myosins-I. Northern blot, immunoblot, and immunolocalization studies indicate that the intestine-specific and subcellular localization profile of mouse brush border myosin-I are comparable to that determined for other brush border myosins-I. Northern analysis during embryogenesis revealed a 3.9-kb transcript first detected in 15-day embryos. This is in marked contrast to chicken, where brush border myosin-I expression begins early in embryogenesis. In situ localization in 17-day embryos indicated that RNA expression is restricted to the intestine. Protein expression is first detected in 16-day embryos with decreasing levels observed in a proximal to distal fashion. Immunolocalization in embryonic intestine revealed that brush border myosin-I is evenly distributed on both apical and basolateral membrane domains. There is also pronounced localization to a supranuclear region, presumably the Golgi apparatus. This suggests that brush border myosin-I may be targeted to the plasma membrane on Golgi-derived vesicles rather than by direct targeting to microvillar actin cores.


Subject(s)
Cloning, Molecular , Gene Expression Regulation, Developmental , Microvilli/genetics , Myosins/genetics , Sequence Analysis, DNA , Animals , Base Sequence , Blotting, Northern , Cell Membrane/ultrastructure , Chickens , Embryonic and Fetal Development/genetics , Humans , Intestines/growth & development , Intestines/physiology , Mice , Microvilli/metabolism , Molecular Sequence Data , Myosins/metabolism , Rats
10.
Cell Motil Cytoskeleton ; 41(4): 308-24, 1998.
Article in English | MEDLINE | ID: mdl-9858156

ABSTRACT

The human intestinal cell line, Caco-2BBe, has been established as an excellent model system for analysis of the enterocyte cytoskeleton including that of the actin rich apical brush border. To facilitate its use for functional analysis of a major component of the brush border, brush border myosin-I, human cDNAs encoding the heavy chain of this class I myosin were isolated and sequenced. The identity of this myosin as human brush border myosin-I was verified based on similarity with other vertebrate sequences, as well as its expression profile at both the RNA and protein levels. Localization of the protein in human intestine along the crypt-villus axis closely resembles that previously determined for brush border myosin-I in chicken, and is quite distinct from that of myosin-Ic, another myosin-I expressed in human intestine and Caco-2BBe cells. In immature cells of the crypt, brush border myosin-I staining is low, and there is significant cytosolic and basolateral localization, while villus cells stain much more intensely, and the protein is primarily localized to the brush border. Localization of myosin-Ic is essentially the inverse of brush border myosin-I in that crypt cells exhibit higher levels of staining, while villus cells have very low levels of myosin-Ic. The expression of both myosins-I was also examined during cell-contact induced differentiation of Caco-2BBe cells where expression and changes in localization closely resemble those that accompany differentiation of enterocyte in vivo.


Subject(s)
Intestinal Mucosa/metabolism , Myosin Heavy Chains/genetics , Amino Acid Sequence , Animals , Base Sequence , Caco-2 Cells , Cell Communication , Cell Differentiation , Cloning, Molecular , DNA, Complementary , Gene Expression , Humans , Microvilli/metabolism , Molecular Sequence Data , Myosin Heavy Chains/classification , RNA , Sequence Analysis, DNA , Tissue Distribution
11.
Int J Occup Saf Ergon ; 4(1): 107-116, 1998.
Article in English | MEDLINE | ID: mdl-10602612

ABSTRACT

The acute-toxic-class method (ATC) is an alternative to the classical LD&inf50; test. Four substances were tested with an ATC testing procedure. The results were compared with LD&inf50; data obtained from the literature. Great importance was attached to the observations of toxic signs following administration. The results of this study have shown that the ATC method allows allocation to toxicity classes in the same manner as on the basis of the classical LD&inf50; tests. The ATC method uses fewer animals and yields the same information on toxic signs. Introducing the ATC method into the quality system allows estimating the acute oral toxicity of chemicals according to the Organisation for Economic Cooperation and Development (OECD; OECD, 1992, 1996).

12.
J Pharm Pharmacol ; 49(11): 1082-5, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9401942

ABSTRACT

A change in the functioning of the liver as a result of experimental cholestasis could result in a change in the biotransformation of drugs. The aim of this study was to evaluate the effect of extrahepatic cholestasis on the pharmacokinetics of digoxin. The investigation was performed on male rabbits randomly divided into two groups: sham-operated and animals with bile-duct ligation. Digoxin (0.02 mg kg-1) was administered intragastrically as a single dose. Biomedical and anatomo-pathological tests and pharmacokinetic assays were performed before the operation and on the 6th day after surgery. A significant increase in area under the serum concentration-time curve and in mean residence time, a decrease in total body clearance, a reduction in the volume of distribution and increases in maximum concentration and the time to reach maximum concentration were observed in animals with the bile-duct ligation. These results suggest reduced elimination of digoxin in animals with obstructive cholestasis.


Subject(s)
Cardiotonic Agents/pharmacokinetics , Cholestasis, Extrahepatic/metabolism , Digoxin/pharmacokinetics , Administration, Oral , Animals , Body Weight/drug effects , Cardiotonic Agents/blood , Cholestasis, Extrahepatic/pathology , Digoxin/blood , Male , Metabolic Clearance Rate , Rabbits
14.
Genomics ; 36(3): 431-9, 1996 Sep 15.
Article in English | MEDLINE | ID: mdl-8884266

ABSTRACT

Myosins are molecular motors that move along filamentous actin. Seven classes of myosin are expressed in vertebrates: conventional myosin, or myosin-II, as well as the 6 unconventional myosin classes-I, -V, -VI, -VII, -IX, and -X. We have mapped in mouse 22 probes encompassing all known unconventional myosins and, as a result, have identified 16 potential unconventional myosin genes. These genes include 7 myosins-I, 2 myosins-V, 1 myosin-VI, 3 myosins-VII, 2 myosins-IX, and 1 myosin-X. The map location of 5 of these genes was identified in human chromosomes by fluorescence in situ hybridization.


Subject(s)
Chromosome Mapping , Myosins/genetics , Animals , Female , Humans , In Situ Hybridization, Fluorescence , Male , Mice , Mice, Inbred C57BL , Molecular Sequence Data
15.
Psychiatr Pol ; 30(2): 247-54, 1996.
Article in Polish | MEDLINE | ID: mdl-8650286

ABSTRACT

UNLABELLED: The report deals with psychoprophylaxis of children and youth being in danger of alcoholism, drug addiction, juvenile delinquency and suicide. In the Psychiatric Out-patient Department in Gdynia we have been practising psychological, social and art-therapeutic care to the youth, and rendering training to their families and tutors (Consulting-Psychoprophylactic Club). The authoresses describe one example of art-therapeutic expression included in two series of pictures made by a girl (4 years old) and her brother (9 years old) after the tragedy of their mother's being killed by their father. CONCLUSIONS: This type of therapy facilitates the experience and release of stress is helpful in improving the relationship between the child and his frequently awkward tutors.


Subject(s)
Adolescent Behavior , Art Therapy , Mental Disorders/therapy , Psychology, Adolescent , Adolescent , Child , Child, Preschool , Female , Homicide , Humans , Life Change Events , Male , Mental Disorders/prevention & control
16.
Br J Pharmacol ; 117(1): 1-4, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8825335

ABSTRACT

1. An altered functional state of liver due to experimental cholestasis could result in a change in the biotransformation of drugs. The aim of this study was to evaluate an influence of obstructive cholestasis on the pharmacokinetics of phenazone (antipyrine). 2. The investigation was carried out on male rabbits, randomly allocated into two groups: shamoperated and animals with biliary ducts ligation. Phenazone was administered intragastrically as a probe of drug metabolism. 3. Measurements, i.e. laboratory and pharmacodynamic tests, as well as pharmacokinetic assays, were performed before the operation as well as 10-12 days after the bile duct ligation. At the end of the study livers were examined macro- and microscopically and biochemical analysis of the liver microsomes was performed. 4. The measured pharmacokinetic parameters suggested an impaired biotransformation of phenazone in animals with obstructive cholestasis, leading to a slower drug elimination.


Subject(s)
Antipyrine/pharmacokinetics , Cholestasis, Extrahepatic/physiopathology , Common Bile Duct/physiopathology , Animals , Biotransformation , Half-Life , Liver Function Tests , Male , Rabbits
18.
Phytomedicine ; 2(3): 199-204, 1996 Jan.
Article in English | MEDLINE | ID: mdl-23194616

ABSTRACT

Thirty male mongrel rabbits were divided into 3 equal groups: (1) controls, (2) animals receiving a high-fat diet (HFD) containing cholesterol and coconut oil, and (3) HFD + lecithin. The experiment lasted 12 weeks. In animals receiving a HFD (group II) the QRS interval (ECG) was significantly prolonged, and the concentration of lipid fractions (except for HDL-cholesterol) and malondialdehyde (MDA) in the blood was markedly elevated. Distinctly lower concentrations of zinc in the serum and cytochrome P-450 in the liver microsomes were observed. When administered together with the HFD, lecithin normalized QRS interval duration, inhibited the diet-induced lipid metabolism disturbances, reduced MDA concentrations and increased zinc concentrations in the serum. Elevated under the influence of lecithin, the content of cytochrome P-450 in the liver microsomes was shown. Surface area of the lipid deposits at 12 weeks, measured planimetrically averaged 24.43% in HFD-fed animals vs 9.28% in lecithin-treated rabbits. We conclude that lecithin is responsible, not only for the hypolipidaemic properties, but also for the antiatherosclerotic action in rabbits.

19.
Eur J Drug Metab Pharmacokinet ; 20(2): 119-23, 1995.
Article in English | MEDLINE | ID: mdl-8582436

ABSTRACT

The aim of this study was to evaluate, using an experimental model, the effect of obstructive cholestasis on the pharmacokinetics of lidocaine and the formation rate of its major metabolite- monoethylglycinexylidide (MEGX)-in rabbits. The investigation was carried out on 20 rabbits, randomly divided into two groups: a control one sham-operated and an experimental one-animals with biliary duct ligation. The measurements, i.e. laboratory and pharmacodynamic tests, as well as pharmacokinetic assays were performed prior to the operation as well as 10-12 days after the bile duct ligation. At the end stage of the study, livers were examined macro- and microscopically and biochemical analysis of the liver microsomes were performed. Lidocaine was given intravenously, as a bolus of 6 mg/kg. Blood for pharmacokinetic assay was sampled within 6 h following the drug administration, and MEGX concentration was evaluated 15 min after lidocaine had been administered. The immunofluorescence polarization method was employed for determination of lidocaine and MEGX concentrations. The one-compartment open model was used for calculations.


Subject(s)
Cholestasis, Extrahepatic/metabolism , Common Bile Duct Diseases/metabolism , Lidocaine/analogs & derivatives , Animals , Fluorescent Antibody Technique , Hypnotics and Sedatives/pharmacology , Lidocaine/pharmacokinetics , Liver/metabolism , Liver/physiology , Male , Organ Size , Pentobarbital/pharmacology , Rabbits , Sleep/drug effects
20.
Pol Tyg Lek ; 47(42-43): 964-6, 1992.
Article in Polish | MEDLINE | ID: mdl-1300589

ABSTRACT

Ten injections of O3 into femoral arteries were administered to 50 patients with atherosclerotic ischemia of the lower extremities and to 49 diabetic patients. All patients were assessed clinically with the ankle-arm index, measurement of intermittent claudication distance prior to and after the treatment. The treatment showed a significant improvement in both groups manifested by an increase in ankle-arm index, and prolongation of the intermittent claudication distance by more than twice. The treatment of atherosclerotic ischemia of the lower extremities with O3 is both valuable and safe.


Subject(s)
Arteriosclerosis/complications , Ischemia/therapy , Leg/blood supply , Ozone/therapeutic use , Female , Humans , Injections, Intra-Arterial , Intermittent Claudication/prevention & control , Male , Middle Aged , Ozone/administration & dosage , Treatment Outcome
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