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J Wojciechowski

Publications and source records attributed to J Wojciechowski.

At least 19 recordsLinked to original sources
PubMed2005

Role of p53 tumor suppressor in ageing: regulation of transient cell cycle arrest and terminal senescence.

In this study we investigated the function of p53 as a regulator of cell cycle progression in cycling and senescent cells. Using the conditional temperature-sensitive (ts) mutant we could prevent the detrimental effect of constitutive expression of high levels of wt p53 protein. High levels of wt p53 inhibited cell proliferation by blocking the cells to progress from G1 to S phase of the cell cycle. Flow cytometric analysis revelaed a maintenance of G1 cell population for a longer time depending on the prolonged expression of wt p53 protein. The p53 mediated inhibition of cell proliferation and of the cycle was reversible. However, a spontaneous increase of wt p53 occurring in ageing normal human MRC-5 fibroblasts was associated with irreversible reduction of proliferative potential. The accumulation of G1 cells was detected by flow cytometry. By the measurement of DNA content it is not possible to discriminate between cells arrested in G1 and G0 phase, therefore, the expression of G1 markers was determined. Analysis of the expression of distinct cell cycle regulators revealed that quiescent MRC-5 cells were in G0 phase. Our results indicate that cell cycle arrest occurring in senescent cells is associated with the G0 transition.

Animals↗
PubMed2003

Activation of p53 protein in normal and in tumor cells by a novel anticancer agent CHS 828.

CHS 828, a novel cyanoguanidine, represents a new class of drugs for cancer therapy, with an unknown primary mechanism of action. It is generally known that anticancer drugs induce p53 response thereby triggering cell cycle arrest or apoptosis. We investigated the effect of CHS 828 on p53 response in normal and tumor cells and compared this effect with that exerted by conventional anticancer drugs. After 24 h of treatment with CHS 828, we observed a dose-dependent up-regulation of wild type (WT) p53 protein in human breast carcinoma MCF-7 cells as well as in normal human and mouse fibroblasts. The highest p53 increase was observed at 300 nM to 1 microM CHS 828. CHS 828 induced phosphorylation of p53 protein at Ser-15 in normal cells. However, the drug failed to induce p53 protein in mouse cells in which the poly(ADP-ribose)-1 gene (PARP-1) was disrupted even at a 30-fold higher dose and after prolonged treatment. Combined treatment of PARP-1 -/- cells by multidrug resistance modulators did not alter p53 expression. CHS 828 inhibited cell proliferation and DNA replication in the tested cells. Interestingly, DNA synthesis as well as proliferation of PARP-1 deficient cells was inhibited by drug concentrations that were approximately 3-fold lower than their conventional counterparts. Treatment of cells with CHS 828 for 48 h did not induce apoptosis.

Animals↗
PubMed1999

DLA-DRB1 histocompatibility genotyping using RT-nested PCR and cycle sequencing.

Class-II histocompatibility genes are associated with predisposition to autoimmune diseases in many mammal species. We have developed a technique using reverse transcriptase and nested-PCR for amplification from blood samples of expressed sequences encoded by canine DLA-DRB1 loci. In the first polymerase chain reaction (PCR), we utilize primers DR-SP and DR-STOP as developed by Sarmiento et al. (1990). In the nested PCR, we utilize two additional primers, namely primer 57 [5'-TCTTGGAGGCTCCTGGATGACAGC-3'] and primer 367 [5'-CACAACTACGGGGTGATTGAGAGC-3'] to produce a 334 bp amplified product. After digestion with restriction endonucleases, some of the alleles can be identified by restriction fragment length polymorphism (RFLP). The increasing information on new DLA-DRB1 alleles over the last two years renders the DLA-DRB1 too diverse for convenient use of RFLP. However, the expressed sequences amplified by our protocol can be conveniently identified by cycle sequencing. This RT n-PCR protocol will suffice for the genotyping of individual dogs at the DLA-DRB1 locus.

Alleles↗
PubMed1998

Expanded indications for the treatment of postcatheterization femoral pseudoaneurysms with ultrasound-guided compression.

BACKGROUND: The purpose of this study was to define the factors that predict successful ultrasound-guided compression repair (UGCR) of postcatheterization femoral pseudoaneurysms (PA) and to determine risks for recurrence, the most appropriate follow-up, and the optimal management of compression failures and recurrences. METHODS: A retrospective chart review was made. RESULTS: UGCR thrombosed 52 of 60 PA (87%). Predictors of compression failure were PA size of 8 cm and an associated arteriovenous fistula (AVF). AVF was the only predictor of recurrence. All seven recurrences (13%) were discovered on the first follow-up scan. Four were thrombosed with additional UGCR. Late rescanning after a mean of 264 days identified no recurrences. Four anticoagulated patients failed initial UGCR but were thrombosed in another session when their anticoagulation was briefly reversed. CONCLUSIONS: UGCR should be the initial management of PA because it is safe, effective, and durable. Temporary discontinuation of anticoagulation and multiple prolonged compression sessions may help treat recalcitrant cases. One follow-up scan is adequate for most patients. Recurrences should be initially treated with repeat UGCR.

Adult↗
PubMed1990

Double contrast barium enema and flexible rectosigmoidoscopy: a reliable diagnostic combination for detection of colorectal neoplasm.

The efficiency of double contrast barium enema and flexible rectosigmoidoscopy (to 60 cm) in the assessment of patients with a positive Hemoccult II test in a randomized screening study for colorectal neoplasms was evaluated. A positive test was present in 625 patients, of whom 530 had a complete enema and rectosigmoidoscopic assessment. A carcinoma was diagnosed in 26 and an adenoma greater than or equal to 1 cm in diameter in 71. As a control, 323 patients with a negative assessment repeated the Hemoccult II test and of these 67 had a positive second test, of whom 55 underwent colonoscopy. One carcinoma (Dukes' A) and two adenomas greater than or equal to 1 cm in diameter were diagnosed. The efficiency of the assessment was also checked by rescreening the whole group 1-2 years after the first study and by continuing follow-up. It was found that two more carcinomas and one adenoma greater than or equal to 1 cm in diameter had been overlooked at the primary assessment. The sensitivity for neoplasms greater than or equal to 1 cm in diameter at the primary assessment was 72 per cent for double contrast barium enema and 86 per cent for rectosigmoidoscopy. The sensitivity for the combined methods was 94 per cent and the specificity was 99 per cent. The combination of double contrast barium enema and rectosigmoidoscopy in the primary assessment of patients with a positive Hemoccult II test gives an acceptable result and immediate retesting of those with a negative assessment is not necessary.

Adenoma↗
PubMed1985

"Half-way" venous catheters. II. Anatomoradiological basis.

In order to develop a "half-way" venous catheter for clinical use, anthropometric (n = 200), radiographic (n = 101), and phlebographic (n = 44) investigations were undertaken to determine the lengths, diameters, and morphology of the basilic and cephalic veins from fossa cubiti to the lateral edge of the first rib. The lengths of basilic and cephalic veins varied from 25 to 45 cm, exceeding 40 cm in approximately 5% of cases. Catheter lengths to be inserted were correlated ("r" = 0.6-0.7) with body heights, accurately estimated by 1/5 of the body height (cm) plus 2 cm for the basilic vein, and 4 cm for the cephalic vein. The cephalic veins have small proximal end diameters (mean = 6 mm), and present terminal arches of 2-3 cm. These are connected by a rich anastomotic network to the superficial cervical veins. The basilico-axillary courses are regular with gradually increasing diameters (mean = 16 mm), but in some observations, with the arms maximally abducted, the axillary veins presented accentuated folds. With these considerations, we recommend the insertion of the "half-way" catheters by basilic approach with the patient's arm in 90 degree abduction. The axillosubclavian length (mean = 18.5 cm) ensures wide limits for accurate placement of the "half-way" catheter tips when a basilic approach is used. Further, their large diameters (16-19 mm) make flotation of the soft catheters probable.

Adolescent↗
PubMed1985

"Half-way" venous catheters. III. Tip displacements with movements of the upper extremity.

Directions and sizes of displacement of "half-way" catheter tips with movements of the upper extremities were investigated in thoracic radiographs in 21 patients (10 women and 11 men), 28-88 years old. Ten catheters were inserted by basilic, and 11 by cephalic veins punctured at the fossa cubiti. Catheter tip positions were related to the lateral edge of the first rib. The tip position with the patient's arm in 90 degree abduction was considered as the reference point. Displacements caused by maximal flexion of the forearm, maximal adduction of the upper extremity, and maximal elevation of the brachium plus maximal flexion of the forearm were studied. With all movements and venous approaches there were significantly more medial than lateral displacements (P less than 0.001). The medial displacements varied from 0.2-5.0 cm, and the lateral ones from 0.5-1.8 cm. Location of the "half-way" catheter tips in the proximal axillary vein, at the lateral edge of the first rib, is recommended. As found previously, this may be obtained by inserting a catheter length representing 1/5 of the patient's height. Such a location inhibits harbouring of the "half-way" catheter tips in the jugular veins with movement in the upper extremities. Furthermore, estimation of central venous pressures by axillary venous pressures is not affected.

Adult↗
PubMed1985

"Half-way" venous catheters. IV. Clinical experience and thrombogenicity.

"Half-way", Secalon-Seldy, soft venous catheters, 40 cm long, were inserted by basilic (n = 90) and cephalic (n = 31) veins at the fossa cubiti in 121 patients (71 men and 50 women) aged between 19 and 88 years whose heights varied from 152-197 cm. The inserted catheter lengths approximated 1/5 of the patient's height. Sixty-five per cent of 106 radiologically investigated catheter tips were located proximally in the axillary veins, and 34% distally in the subclavian veins. The duration of catheterization varied from 1 to 44 (mean 9 +/- 7) days (means +/- 1 s.d.). Perfect function was recorded in 93 of 121 catheters. No serious, but some minor complications were registered such as temporary interruption of infusion flow with movements of the arm (n = 12), partial or total catheter occlusion (n = 16), leakage of the infusate at the insertion site (n = 1), and pain along the vein during infusion (n = 2). Five patients (4%) developed thrombophlebitis 2-.10 days after insertion. Pull out phlebographies at catheter withdrawal (4-35 days after insertion) were performed in 36 patients. Radiological thrombi were small and similar to those recorded in another 53 phlebographies of "long-way" brachial catheters of similar stiffness. Neither local infection nor episodes of sepsis were registered over a period of 1,081 catheter days. "Half-way" catheters proved able to take over all the functions of both peripheral and central venous catheters, lacking the frequent complications (phlebitis and infection) of the former, and the serious mechanical complications (pneumothorax, vein perforations, and injuries of the ductus thoracicus, nerves, arteries, and heart) of the latter.

Adult↗
PubMed1983

Prevalence of secondary hypertension in a population sample of Swedish women.

In a comprehensive population study of 1462 women aged 38--60 in Göteborg, Sweden, the prevalence of secondary hypertension was estimated to be 0.8% of the total population sample and 4.6% of those who were hypertensive (defined as systolic blood pressure greater than or equal to 160 mmHg or diastolic blood pressure greater than or equal to 95 mmHg or both or antihypertensive treatment irrespective of blood pressure levels). These figures were based on thorough clinical and laboratory investigations and a follow-up period of 12 years. Women with arterial hypertension reported a history of toxaemia of pregnancy and a family history of hypertension more often than non-hypertensive women. In comparison with non-hypertensive women, in both untreated and treated hypertensive women, serum uric acid, urinary methoxycatecholamine excretion, body weight and the prevalence of albuminuria were increased and serum potassium decreased (statistically significant differences).

Adrenal Cortex Hormones↗
PubMed1983

Material thrombogenicity in central venous catheterization II. A comparison between plain silicone elastomer, and plain polyethylene, long, antebrachial catheters.

Central venous catheters of two types were inserted through basilic or cephalic veins punctured at the fossa cubiti in 61 patients: 39 soft silicone elastomer (S.E.) and 22 stiffer polyethylene (P.E.) catheters were compared regarding their thrombogenicity. Mean duration of catheterization was 6.5 days. Radiological thrombi in the peripheral and central veins visualized by phlebography were significantly smaller, and the incidence of the mural thrombi in the central veins significantly lower with the S.E. than with the P.E.-catheters, but the use of S.E.-catheters did not reduce the incidence of clinical thrombophlebitis in arm veins: 14 cases in the group with S.E. and four in that with P.E.-catheters. In both groups, the maximum incidence of clinical thrombophlebitis occurred 4-8 days after catheterization. Later, there seems to be a low risk for the appearance of clinical thrombophlebitis with both catheters. Neither the surface topography of the catheter materials, nor the platelet adhesion on their surfaces in contact with human blood in vitro offered conclusive arguments for interpretation of their thrombogenicity in vivo. Catheter stiffness seems to play an important role in inducing mural thrombus formation in central venous cannulation in man.

Adolescent↗
PubMed1983

Fibrinopeptide A, beta-thromboglobulin, and fibrin degradation products as screening test for the diagnosis of deep vein thrombosis.

In a group of 111 consecutive patients (mean age 65 years) with suspected deep venous thrombosis (DVT) phlebography demonstrated DVT in 51. In all patients blood tests for fibrinopeptide A (FPA), fibrin degradation products (FDP) and beta-thromboglobulin (beta-Tg) were carried out. There was a significant difference in FPA concentration between the group of patients with a positive and a negative phlebography. However, there was a wide variation of individual values in both groups. The difference in FPA concentration between the groups was not related to differences in predisposing diseases, age or sex. FDP and beta-Tg did not differ between the groups and, again, a wide variation of individual values was found in both groups. In our hands, none of these three methods reflecting activities in the hemostasis seems to be useful to diagnose DVT in clinical routine work.

Adult↗
PubMed1982

Prediction and prophylaxis of postoperative thromboembolism--a comparison between peroperative calf muscle stimulation with groups of impulses and dextran 40.

The effects of peroperative electrical calf muscle stimulation with groups of impulses giving a short lasting tetanus of the calf muscles on postoperative deep venous thrombosis (DVT) and pulmonary embolism (PE) were compared with that of dextran 40 given per and postoperatively. The incidence of DVT and PE during the first 4-6 postoperative days was recorded. The diagnosis of DVT was based on the 125I-fibrinogen uptake test and phlebography and of PE on pre- and postoperative perfusion pulmonary scintigram and chest X-ray examination. Both methods reduced the incidence of PE. Calf muscle stimulation reduced the DVT incidence in patients with malignant disease while the reduction in DVT incidence for the whole group only was significant in the stimulation as well as the dextran 40 group. Mean values for preoperatively determined levels of antithrombin III, beta-thromboglobulin, fibrinopeptide A, plasminogen and ability to release fibrinolytic activity during venous stasis did not differ between those patients who developed or those who did not develop postoperative DVT or PE. However, antithrombin III levels below 80 per cent appeared to predispose to postoperative thromboembolism. The two prophylactic methods have similar effects on the incidence of postoperative thromboembolism. The stimulation method has certain advantages due to its safety and simplicity.

Adult↗
PubMed1982

Iopamidol compared with Conray in peripheral angiography.

In patients with arteriosclerotic disease in the legs, peripheral angiography was performed double blind with the non-ionic contrast medium Iopamidol and the ionic medium iothalamate meglumine (Conray 60). Iopamidol caused less subjective adverse effects and less changes in blood pressure.

Aged↗
PubMed1982

Thermography and phlebography in the detection of incompetent perforating veins.

In 22 patients with deep venous insufficiency thermography performed at rest and immediately after exercise was compared with conventional ascending phlebography. Thermography was found to have a high sensitivity in detecting incompetent perforating veins, while the specificity was low. The non-invasive thermography is an attractive technique for preoperative detection of perforating veins.

Adult↗
PubMed1981

Thermography as a screening method in the diagnosis of deep venous thrombosis of the leg.

Thermography was performed before ascending phlebography in a series of 232 patients with suggested deep venous thrombosis. Thirty per cent of the patients were thermo-negative. The predictive value of a negative thermography was 88 per cent. Thermography is useful as a screening method, but it has low specificity and thus a relatively high incidence of false positives must be accepted.

Adolescent↗
PubMed1980

Thermographic demonstration of uneven myocardial cooling in patients with coronary lesions.

Low temperature is an important factor in protecting the myocardium during an operation on the heart. This can be difficult to accomplish if the cold cardioplegic solution is hindered by occlusions or stenosis of the coronary arteries. We used thermography to study myocardial temperature during infusion of cold cardioplegic solution. Slow cooling was recorded distal to coronary stenosis or occlusions, thereby indicating insufficient protection of the myocarium in these areas.

Aortic Valve Stenosis↗