A massive binary black-hole system in OJ 287 and a test of general relativity.

Tests of Einstein's general theory of relativity have mostly been carried out in weak gravitational fields where the space-time curvature effects are first-order deviations from Newton's theory. Binary pulsars provide a means of probing the strong gravitational field around a neutron star, but strong-field effects may be best tested in systems containing black holes. Here we report such a test in a close binary system of two candidate black holes in the quasar OJ 287. This quasar shows quasi-periodic optical outbursts at 12-year intervals, with two outburst peaks per interval. The latest outburst occurred in September 2007, within a day of the time predicted by the binary black-hole model and general relativity. The observations confirm the binary nature of the system and also provide evidence for the loss of orbital energy in agreement (within 10 per cent) with the emission of gravitational waves from the system. In the absence of gravitational wave emission the outburst would have happened 20 days later.

The influence of prolactin on the chosen biochemical parameters of the rabbit liver in ischemia.

An experimental model, based on Pringle's scheme of acute warm hepatic ischemia in normothermia was employed in order to study the hepatoprotective properties of prolactin (PRL). In the proposed model one liver lobe was maintained in the portal circulation and the remaining lobes were perfused with HTK solution for 2 hours. The experiment was carried out on female rabbits of the Chinchilla race. In the control group (n= 10) the liver was perfused with HTK solution. In the examined group (n=10), 3 microg of PRL per g of liver per hour was added to HTK solution. Additionally, the animals in the PRL-treated group were intravenously administered a dose of 600 microg of PRL / kg body weight. 1 h before the surgical treatment. The activities of alanine aminotransferase (ALT), alkaline phosphatase (ALP). gamma-glutamyl transferase (GGT) and the lactate concentration were determined in the eluate obtained from the perfused part of the liver. It was found that administration of prolactin during 2 h of perfusion led to a significant decrease of ALT, ALP and lactate concentrations in the eluate. In addition, increase of calcium concentration in the liver was significantly lower with the prolactin group. The observed results let us to draw the conclusion that administration of PRL shows signs of protective effects on hepatocytes in normothermic acute ischemia.

Composition of the editing complex of Trypanosoma brucei.

The RNA editing that produces most functional mRNAs in trypanosomes is catalysed by a multiprotein complex. This complex catalyses the endoribonucleolytic cleavage, uridylate addition and removal, and RNA ligation steps of the editing process. Enzymatic and in vitro editing analyses reveal that each catalytic step contributes to the specificity of the editing and, together with the interaction between gRNA and the mRNA, results in precisely edited mRNAs. Tandem mass spectrometric analysis was used to identify the genes for several components of biochemically purified editing complexes. Their identity and presence in the editing complex were confirmed using immunochemical analyses utilizing mAbs specific to the editing complex components. The genes for two RNA ligases were identified. Genetic studies show that some, but not all, of the components of the complex are essential for editing. The TbMP52 RNA ligase is essential for editing while the TbMP48 RNA ligase is not. Editing was found to be essential in bloodstream form trypanosomes. This is surprising because mutants devoid of genes encoding RNAs that become edited survive as bloodstream forms but encouraging since editing complex components may be targets for chemotherapy.

[Renal osteodystrophy in dialysis patients as estimated by three-point bone densitometry]. / Osteodystrofia nerkowa u chorych dializowanych w ocenie trzypunktowego pomiaru densytometrycznego.

The aim of a study was to estimate the renal osteodystrophy status using bone densitometry in relation to selected biochemical parameters of calcium-phosphate metabolism. The study population consisted of 123 patients with end-stage renal disease, including 24 patients treated with continuous ambulatory peritoneal dialysis (CAPD), aged between 22 and 73 years (mean 49.9 years), on dialysis program for mean period of 14.9 months and 99 patients on maintenance hemodialysis for mean period of 58.8 months, aged between 19 and 72 years (mean 46.6 years). Densitometric measurements using DEXA technique were performed in three different skeletal points: distal ends of both radial bones, lumbar spinal region and femoral neck. Concomitantly, serum concentrations of total and ionized calcium, phosphates and parathormone as well as alkaline phosphatase serum activity were measured. Among male patients treated with CAPD significantly higher BMD values in right forearm were found as compared to women treated with this method (0.769 vs. 0.616; p < 0.001). Higher values of BMD were also found in both forearms in whole CAPD population as compared to those on hemodialysis. However, there was no difference in densitometry results between CAPD and HD patients as well as between men and women within these groups, when measured in femoral neck and lumbar spinal region. Among hemodialysis patients higher levels of phosphates and PTH were found as compared to CAPD, doses of drugs used for treatment of osteodystrophy--calcium carbonate, aluminum hydroxide and active vitamin D were also higher in individuals on HD. In addition, in CAPD patients statistically significant, positive correlations were found between BMD value in lumbar spinal area as well as in femoral neck and amount of ingested calcium carbonate, between BMD in lumbar spinal area and aluminum hydroxide dose taken by patients and between BMD in both forearms and dose of active vitamin D. We failed to demonstrate any relationship between obtained densitometric results as well as biochemical markers of calcium-phosphate metabolism and quantitative parameters of dialysis adequacy in both treatment modes. Obtained results let us to conclude that renal osteodystrophy is less advanced in patients treated with peritoneal dialysis, however this may be related only to markedly shorter renal replacement therapy period in this group. Lack of significant abnormalities in densitometry measurements taken in lumbar spinal area and femoral neck, while they are present in forearms, may suggest that the latter point of skeleton may be most useful for identification of bone mass deficiency in dialyzed patients.

[Use of modern microscopic techniques for examining dialysis membrane properties]. / Zastosowanie nowoczesnych technik mikroskopowych w badaniach wlasnosci kapilar dializatorów.

The aim of the study was the microscopic evaluation of internal structure of cuprophane and polysulfone membrane and their surface analysis before and after reprocessing. The investigations were performed using an optical measurement system (Digital Instruments), a scanning electron microscope (SEM) and an atomic force microscope (AFM). We confirmed by SEM that reprocessing completely removed biofilm from both membranes surface. The analysis based on AFM visualized channels in the examined membrane. The diameter of the channels varied from 150 nm for cuprophane to 380 nm for polysulfone. The roughness expressed as root mean square (RMS) was higher for cuprophane than for polysulfone membrane. The physical differences between nanostrucure of the examined membranes might be responsible for lower biocompatibility of cuprophane.

Structure of a regulatory 3' untranslated region from Trypanosoma brucei.

The African trypanosome Trypanosoma brucei multiplies in mammalian extracellular fluids (bloodstream forms) and in the midgut of Tsetse flies (procyclic forms). The control of gene expression that is necessary to survive in these two environments operates almost exclusively at the posttranscriptional level, and the sequences responsible are located in the 3' untranslated regions of the mRNAs. The major surface proteins of procyclic trypanosomes, EP1, EP2, EP3, and GPEET, are not expressed in bloodstream forms. The 3' untranslated regions of these four mRNAs are not very similar, but all contain a conserved 26mer sequence that is required for developmental regulation. We have analyzed the conformation of the EP1 3' UTR in vitro by enzymatic digestion and lead hydrolysis, and in vivo by modification with DMS and with CMCT (introduced by electroporation). Results indicate that the 3' UTR can be divided into three domains. Domains I and III, at the 5' and 3' ends, form stable structures, but the central domain (domain II), which includes the 26mer, has no stable interactions either within itself, or with other parts of the 3' UTR. Domain I contains three leadzymes that do not conform to the previously reported consensus.

Is CAPD a renal replacement therapy method of choice for women?

The aim of this study was to evaluate if there were any differences in clinical outcome as well as in values of quantitative adequacy/nutritional parameters in ESRD patients treated with continuous ambulatory peritoneal dialysis, depending on their sex. Nutritional and adequacy parameters: NPCR, Kt/V, weekly creatinine clearance (wClCr), dialysis index (DI), serum albumin concentration, as well as clinical parameters such as hospitalization rate, admission rate, peritonitis rate, exit-site infection rate and co-morbidity score were evaluated in 31 CAPD patients (12 F and 19 M). Lower comorbidity score (0.583 vs. 1.58 points; p < 0.05) and higher Kt/V total and residual (2.25 vs. 1.57; p < 0.01 and 1.7 vs. 1.42; p < 0.01, respectively) were found in women as compared to men. The value of the quantitative nutritional parameter--NPCR--was also higher in women (0.842 vs. 0.73 g/kg b.w./24 hours; p < 0.05). Despite these differences, only a small difference was found in the clinical outcome and survival between men and women. The obtained data may suggest that women can achieve better treatment results with the CAPD method as compared to men.

[The usefulness of normalized protein catabolic rate (NPCR) and serum albumin concentration measurement for evaluation of clinical status in patients treated with continuous ambulatory peritoneal dialysis]. / Uzytecznosc znormalizowanego wspólczynnika katabolizmu bialka (NPCR) oraz pomiaru stezenia albuminy w surowicy krwi do oceny stanu klinicznego pacjentów leczonych ciagla ambulatoryjna dializa otrzewnowa.

Malnutrition is a serious and common problem among patients dialyzed with peritoneal dialysis. Simple and reproducible methods of nutritional status assessment are needed for early problem identification to prevent and treat this complication. The aim of the present study was to evaluate the usefulness of albumin serum concentration and normalized protein catabolic rate (NPCR) derived from urea kinetic modeling session to assess the clinical status of ESRD patients treated with Continuous Ambulatory Peritoneal Dialysis (CAPD). Statistically significant, negative correlations between NPCR and hospitalization rate (r = -0.307; p < 0.05) and co-morbidity score (r = -0.429; p < 0.001) as well as statistically higher NPCR in the group of patients who survived the whole study period (0.82 vs. 0.74 in Non-Survivors; p < 0.01) support the value of this marker as an indicator of clinical status of peritoneal dialysis patients. Significant, negative correlations between serum albumin level and co-morbidity score (r = -0.379; p < 0.05), peritonitis rate (r = -0.359; p < 0.05) and hospitalization rate (r = -0.601; p < 0.005) were also found. Low absolute values of NPCR for the whole population as well as significant, positive correlations of this marker with dialysis adequacy parameters with concomitant lack of such correlations for albumin indicate, that NPCR as a nutritional marker should be interpreted with caution, and always regarded to the calculation method.

Progression to end-stage renal disease in children with posterior urethral valves.

Diagnostic and therapeutic strategies in boys with congenital posterior urethral valves (PUV) have much improved in past decades, but the impact of these changes on the progression to end-stage renal disease (ESRD) has rarely been investigated. We followed renal function in 20 boys with PUV from diagnosis to ESRD. From the first observation period (1969-1978) to the second period (1979-1992) we found a marked drop in age at diagnosis, at valve resection, at first increase of serum creatinine (SCr), and at onset of ESRD. The progression was analyzed by calculating the slope of 1/SCr and the probability of renal survival. In all patients combined, renal survival at the age of 10 years was 35%. In children undergoing valve resection in the 1st year of life, renal survival was worse than in those undergoing later surgery (15% vs. 65% after 10 years, P=0.006). Patients with a SCr>1.2 mg/dl before the age of 12 months progressed more rapidly to ESRD than those attaining this level later. The lower the minimum level of SCr observed after initial surgery, the older the patient at the onset of ESRD. The presence of renal dysplasia or hypoplasia, but not of vesicoureteric reflux, was associated with a more rapid progression. Mean body height at ESRD was -2.3+/-1.3 standard deviation score compared with controls, and was lower if PUV was diagnosed before the age of 6 months.

Circadian variations of androstenedione, dehydroepiandrosterone sulfate and free testosterone in obese women with menstrual disturbances.

OBJECTIVE: To assess the 24 h profile of androgenemia related to the androgens of both the ovarian and adrenal origin in obese women with menstrual disturbances. METHODS: The association of body mass and body fat distribution with circadian variations of selected androgens of ovarian and adrenal origin was examined in 16 obese women with menstrual disturbances (BMI between 38 and 51 kg/m2; WHR between 0.80 and 0.99) and in 16 healthy volunteers with normal body weight (BMI between 21 and 24.6 kg/m2; WHR between 0.73 and 0.76). The age range of all subjects was 29 to 40 (mean: 36.9+/-3.2 years). RESULTS: lts. Both the patients and control subjects showed a significant 24 h rhythm of androstenedione (A) and free testosterone (FT), while the circadian oscillations of dehydroepiandrosterone sulphate (DHEAS) did not differ significantly. In all obese women mean 24 h A, DHEAS and FT levels were significantly higher than those in controls. Moreover, the disturbances of DHEAS and FT secretion in the form of acrophase shift (for DHEAS from 7.37 to 3.45 h and for FT from 6.04 to 3.31 h) and the elevation of their 24 h amplitude values were observed. All obese women showed higher values of FT/A and FT/DHEAS indexes in selected clock time of day/night cycle (except those at 8.00 h for FT/A and at 5.00 h for FT/DHEAS) when compared to control group. A positive correlation was noted in all women studied between the values of BMI index, WHR ratio and mean 24 h level of androgens studied as well as FT/A and FT/ DHEAS indexes. A weaker correlation was found between body mass and body fat distribution on the one hand and fasting level of hormones studied on the other. Higher correlation between the values of WHR ratio and mean 24 h FT levels as well as FT/DHEAS indexes were obtained in obese women when compared to those of healthy subjects. CONCLUSIONS: Our findings suggest that, when assessing the androgen disturbances in obese patients, it is more useful to determine their circadian pattern than the basal level. The most reliable indicators of hyperandrogenism in obese women are: the 24 h concentration profile of FT and the value of FT/DHEAS index, not only during fasting but also after a meal at various time intervals. Circadian FT concentration and FT/DHEAS index values are essential indicators for visceral distribution of adipose tissue.

Assessment of bone metabolism in obese women.

OBJECTIVE: To evaluate the bone metabolism in obese women by the estimation of selected markers of bone formation. METHODS: The concentration of plasma parathyroid hormone (PTH) and selected markers of bone formation [osteocalcin (BGP) in plasma, carboxyterminal propeptide of type I procollagen (PICP) and alkaline phosphatase (AP) activity in blood serum] and bone resorption [cross-linked carboxyterminal telopeptide of type I collagen (ICTP) in blood serum and urinary excretion of calcium (Ca)] in 18 extremely obese women (BMI>40 kg/m2) with android phenotype (WHR>0.8) and in 20 healthy women with normal body weight. The age range of all subjects was 25 to 42 years (mean: 36.82 + 3.95). RESULTS: All obese women showed significantly increased concentration of plasma PTH, BGP and serum PICP, ICTP and elevated urinary excretion of Ca. CONCLUSIONS: The obtained results show that in extremely obese women with android phenotype bone metabolism disturbances may occur pointing at increased bone formation and resorption.

Single-strand breaks and repair in nuclear DNA in the presence of hydralazine assayed by the nucleoid technique.

The nucleoid sedimentation assay was used to study hydralazine-induced DNA structural changes and repair in the fibroblasts cultured in vitro. The drug induced a dose dependent loss in negative DNA supercoiling due to the physical breakage of the DNA. Relaxation of supercoiled DNA resulted in the nucleoids sedimenting with lower velocities than those of undamaged control cultures. Repair incubation of the cells did not cause the restoration of DNA supercoiling to control level. Unsuccessful repair of DNA damaged by hydralazine may result in maintaining the damaged DNA in the cell which could have immunologic consequences.

Assessment of the relationship between collagen metabolism and selected hormonal factors in extremely obese women before and after jejunoileostomy.

The majority of obese persons have hyperinsulinemia and disturbances in the secretion of melatonin, catecholamines and pituitary, thyroid, adrenal and gonadal hormones. These hormones play an important role in the regulation of collagen metabolism either by acting directly or by influencing IGF-I production. This study aimed at ascertaining whether, and to what degree, the changes in the concentration of hormones listed above as well as in the concentration of sex hormone-binding globulin (SHBG) and insulin-like growth factor-I (IGF-I) affect the metabolism of collagen as evaluated indirectly from the measurement of propeptides of type I (PICP) and type III procollagen (PIIINP) in blood serum and hydroxyproline in urine. The study compared 30 women with extreme obesity before and three to five years after jejunoileostomy with 20 healthy women of reproductive age. All non-operated obese women showed significantly increased concentration of serum insulin, IGF-I, melatonin, norepinephrine, free triiodothyronine, estradiol, total and free testosterone, PICP, PIIINP and urinary excretion of hydroxyproline, while the levels of epinephrine, progesterone and SHBG were significantly decreased. Changes in the level of the examined markers of collagen metabolism correlated positively with the concentration of insulin, IGF-I and sex hormones, while the correlation with epinephrine, cortisol and thyroid hormones was negative. All women who were treated previously by jejunoileostomy showed a decreased of body mass to regular values, normalization of hormonal disturbances and normal collagen metabolism. The obtained results show that the increased collagen metabolism observed in extremely obese women is caused indirectly by altered endocrine activity.

Plasma selenium concentration in patients with stomach and colon cancer in the Upper Silesia.

Plasma selenium concentration was assessed in 44 patients with cancer of the gastrointestinal tract (19 subjects with stomach cancer and 25 with colon cancer) and 25 age-matched healthy control subjects. Selenium concentration was determined by the fluorometric method. The observed plasma selenium concentrations in gastrointestinal cancer patients (37.0 +/- 11.05 ng Se/ml or 38.4 +/- 12.6 ng Se/ml in stomach or colon cancer patients, respectively) were significantly lower as compared to the healthy age-matched control group (51.4 +/- 14.4 ng Se/ml). The diagnosed low selenium status may be considered as a high risk for cancer development.

[Causes of peri-operative mortality in patients with esophageal cancer treated surgically (personal material)]. / Przyczyny smiertelnosci okolooperacyjnej chorych z rakiem przelyku leczonych operacyjnie (material wlasny).

99 surgical procedures of thoracic part of esophagus resections were performed between 1985 and 1995. All thoracotomies were right-sided and alimentary canal continuity were substituted with a stomach (or with a small intestine or a colon in only a few cases) transposed inside a thorax cavity. Almost all cases there were planoepitheliale cancers. The sex index (men to women) was 6:1. The main reason of perioperative mortality were pulmonary complications (almost 90%): a respiratory insufficiency, an atelectasias, infections, and a broncho-pleural leakage. The nutrition state, stapler-using, anastomosis leak, and wound-healing way had no influence on mortality rate. Other mortality reasons there were a pleural hemorrhage, a mediastinitis as a result of esophago-gastric anastomosis disruption, a heart infarct, and a thrombo-embolic complications.

[The role of Shouldice's operation in treating inguinal hernia]. / Miejsce operacji Shouldice a w leczeniu przepukliny pachwinowej.

Clinical estimation of Shouldice procedure in the surgical treatment of inguinal hernia was performed in the group of 95 patients (102 operations) treated in the Second Department of General and Vascular Surgery Clinic at Zabrze between 1994 and 1996. Their ages ranged from 18 to 78 years with an average 53.6. The sex index (men to women) was 11:1. The bilateral hernia was found in seven cases and all of them were treated surgically at the same time. The most treated hernias was considered as type II and V by Gilbert classification. Among treated patients there were six cases of recurrence hernia earlier operated according to other procedures (mainly Bassini, Girard, Halsted, and artificial knitted-graft placed up intraperitoneally). In 28 cases of fascia transversalis large deficiency (the third and fourth type of Gilbert classification) authors used the two-layer modification method of reconstruction instead four layer of hernial canal posterior wall reconstruction the typical for Shouldice procedure. It was sufficient in all cases without respect to hernia size and fascia transversalis deficiency. There were no complications in postoperative periods. The recurrence of hernia, appeared only in one patient (0.98%) nine months after operation. In authors opinion, the Shouldice procedure is the most effective among all classical ways of inquinal hernia repairs.

[A case of ectopic breast tissue located in the axilla]. / Przypadek tkanki gruczolu sutkowego ektopowo zlokalizowanej w dole pachowym.

Authors have presented a very rare case of young woman favourable surgically treated for morphologically correct breast tissue in the unilateral axilla. They have paid the peculiar attention to possibility of ectopically placed breast tissue malignancy of every that case.

Assessment of relationship between hypothalamo-pituitary dysfunction and peripheral endocrine function in normotensive and hypertensive obese men.

The relationship between hypothalamo-pituitary function and various hormonal factors (insulin, cortisol, thyroid hormones, sex steroid hormones, SHBG, IGF-I) was investigated in 34 obese men (16 normotensive and 18 hypertensive) and 15 healthy male volunteers aged 35 to 50 years. Hyperinsulinaemia in obese men was associated with altered hypothalamo-pituitary function as indicated by impaired GH, PRL and cortisol secretion in response to insulin induced hypoglycaemia. On the other hand, hyperinsulinaemia and disorders in GH, PRL and cortisol release were associated with lower levels of reverse triiodothyronine, gonadotropins, testosterone, 17-corticoids and SHBG and higher levels of triiodothyronine, estradiol, 17-hydroxycorticoids and IGF-I. Various disorders of hypothalamo-pituitary axis and adrenal, thyroid and testicular function occur more frequently in hypertensive obese men with android distribution of adipose tissue.