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T Block

Publications and source records attributed to T Block.

At least 37 records · Page 2Linked to original sources
PubMed1992

Expression of HER-2/neu in renal-cell carcinoma. Correlation with histologic subtypes and differentiation.

Twenty-four renal-cell carcinomas (RCC) and corresponding non-neoplastic kidney tissue were examined for amplification and expression of the HER-2/neu gene. Gene amplification was examined by slot-blot analysis, mRNA expression by in situ hybridization and Northern blot analysis, and protein expression by immunohistochemistry. Northern-blot analysis revealed lower expression of HER-2/neu mRNA in clear-cell (p less than 0.001) and compact (p less than 0.001) tumor subtypes, while chromophilic, chromophobic and tubulo-papillary subtypes did not show significant differences in HER-2/neu gene expression, as compared with non-neoplastic kidney tissues. HER-2/neu gene expression was not significantly associated with tumor stage. Low differentiation (G3) was associated with lower HER-2/neu gene expression, but the number of G3 cases was too small for statistical analysis. HER-2/neu gene amplification was not found in any of the tumors. The results of in situ hybridization and immunohistochemistry generally agreed with those of Northern-blot analysis. We conclude that HER-2/neu gene expression correlates with Thoenes' classification of RCC and may be inversely related to tumor differentiation; it is probably not involved in progression of RCC, in contrast to carcinomas of other locations (e.g. breast, ovary).

Blotting, Northern↗
PubMed1992

Modulation of in vitro cell growth of human and murine urothelial tumor cell lines under the influence of interleukin-3, granulocyte-, macrophage- and granulocyte-colony-stimulating factor.

To elucidate possible growth-modulating effects of interleukin 3 (IL-3), granulocyte-macrophage-colony-stimulating factor (GM-CSF) and granulocyte-colony-stimulating factor (G-CSF), human transitional cell carcinoma (TCC) cell lines T24, RT112, EJ and 647 V were solitarily and continuously exposed to these hematopoietic growth factors at concentrations of 1-100 ng/ml. The murine line MBT-2 was used as a negative and the colon carcinoma cell line HTB38 as a positive control, because of species specificity and known proliferation in response to growth factors, respectively. In the T24 TCC-line solitary and continuous exposure to IL-3, GM-CSF and G-CSF at the highest concentration of 100 ng/ml led to a significant proliferation of cell growth in vitro. Significant proliferation in the RT112 line was only achieved with continuous exposure to IL-3 and GM-CSF (100 ng/ml); G-CSF failed to induce growth modulation in the RT112 line. No significant proliferative effect of any of cytokines administered was observed in the 647V line. Exposure of the EJ line to cytokines at the highest activity levels had a proliferative effect only in suboptimal growth conditions.

Adenocarcinoma↗
PubMed1992

Implantation metastasis after a suprapubic catheter in a case of bladder cancer.

We report about a patient who was treated with a percutaneous suprapubic cystostomy in order to relieve repeated urinary retention. Two hours later a bladder tumor was found and the suprapubic catheter was removed. After transurethral resection of the bladder tumor the histological specimen showed a pT3 G3 squamous cell carcinoma. Because of the age and reduced performance status of the patient a radical cystectomy was contraindicated. In a second approach we performed again a transurethral resection of the bladder tumor simultaneously with a resection of the prostate. Eight weeks later the patient was admitted to our hospital because of reduced performance status and gross haematuria. We found a widespread bladder tumor with an implantation metastasis in the abdominal wall at the site where the suprapubic catheter was placed and multiple lung metastases. The patient died within one week after admission. The literature is reviewed and therapeutic strategies are discussed.

Aged↗
PubMed1992

Effect of digital rectal examination on serum concentration of prostate-specific antigen.

Prostate-specific antigen (PSA) is used for screening and follow-up of patients with prostate cancer. The effect of certain diagnostic procedures on PSA serum levels is not well defined. Therefore, the effect of digital rectal examination (DRE) on PSA serum levels was investigated. No significant difference was observed in PSA values before and after DRE when blood samples were taken 1-3 min after palpation of the prostate. Kinetic studies demonstrated a significant increase in PSA values up to the factor 3.2 in 14 of 19 patients 2-6 h after DRE. In 9 of 14 cases, PSA was within the initial range 24 h after DRE. That means that a urologist is allowed to take blood samples for the determination of PSA at least within 3 min after palpating a suspicious prostate without getting false-positive results.

Aged↗
PubMed1991

Inhibition of transient gene expression with plasmids encoding herpes simplex virus type 1 UL55 and alpha genes.

Herpes simplex virus type 1 (HSV-1) subgenomic sequences from 0.743 to 0.782 map units have been molecularly cloned as plasmid AT1 and shown to inhibit stable DNA-mediated gene transformation of Ltk- cells with the HSV-1 thymidine kinase (tk) gene. Here it is shown that AT1 also inhibits transient gene expression. Expression from the chloramphenicol acetyltransferase (CAT) gene under the control of either the HSV-1 tk gene or the Rous sarcoma virus (RSV) promoter was inhibited when cotransfected into Ltk- and CV-1 cells with equimolar amounts of AT1. AT1 was subcloned as three overlapping plasmids called AT1a, alpha 27 and AT1b. The alpha 27 plasmid encodes the HSV-1 immediate early gene, alpha 27; AT1a possesses sequences that specify an open reading frame in HSV-1 strain KOS used in these studies, although the significance of this open reading frame is unknown; AT1b possesses the sequences for UL55 and UL56, also genes for which no function has been reported. No single subclone or pair of subclones demonstrated significant inhibition of transient gene expression. Cotransfection of all three subclones did result in inhibition of RSV-CAT gene expression, suggesting that information from each subclone is necessary. One of the three subclones, alpha 27, contains the HSV-1 immediate early gene, alpha 27, so the possibility that other immediate early genes could substitute for alpha 27 was tested. Inhibition of RSV-CAT gene expression was also achieved by cotransfection of AT1a and AT1b with either an alpha 0- or alpha 4-containing plasmid, suggesting that the role of the alpha 27-containing plasmid can be replaced by other alpha genes with trans-regulating capability. Finally, AT1a and AT1b linker insertion mutants have been constructed and used to study the role these plasmids play in mediating inhibition. These results suggest that AT1 contains HSV-1 functions in addition to that of alpha 27 that interfere with gene expression.

Animals↗
PubMed1991

A review of the molecular mechanism of HSV-1 latency.

The neurotropic herpes viruses, as typified by herpes simplex virus type 1, are noted for their ability to form latent infections. The latent infection differs from the acute infection both in gene expression and the physical state of the viral genome. Latency can be divided into several stages--establishment, maintenance of reactivation--each of which are active areas of research. This review describes the molecular biology of HSV-1 latency and presents the current level of understanding of the molecular mechanism of HSV-1 latency.

Animals↗
PubMed1989

Intracavernous self-injection of prostaglandin E1 in the therapy of erectile dysfunction.

The efficacy of intracavernous autoinjection therapy with prostaglandin E1 was investigated over a period of up to six months in 187 patients with long-term erectile dysfunction. All patients had to undergo an investigation program consisting of routine laboratory tests, directional doppler sonography of the penile arteries, measurements of the BCR-latencies, as well as intracuvernum drug testing with PGE1. Six months follow-up results are available so far in 115 patients. The mean injection dose was 13.5 mcg PGE1 at the beginning of therapy and 12.8 mcg PGE1 at the end of therapy. An average of 24 prostaglandin E1 injections per patient was given. In 16.6% of the 187 patients slight to moderate pain occurred at the injection site, not influencing sexual intercourse. No priapisms lasting more than six hours were observed. A significant improvement of the blood flow in the deep and dorsal penile arteries was shown by penile doppler sonography after 6 months treatment. The efficacy and tolerability of the therapy were designated as very good to good in 91% respectively in 98% of the patients. 94% of the patients would like to continue the therapy. The results indicate that PGE1 due to its erectile potency and great tolerability will occupy an important position in the therapy of the erectile dysfunction.

Adult↗
PubMed1988

Herpes simplex virus type 1 alpha gene containing plasmids can inhibit expression regulated from an alpha promoter in CV-1 but not HeLa cells.

Transfection of plasmids containing the herpes simplex virus type 1 (HSV-1) alpha gene 27 has been observed to inhibit gene expression from a virus alpha promoter in monkey (CV-1) but not human (HeLa) cells in a transient gene expression system. DNA mediated gene transfer to CV-1 and HeLa cells of the bacterial gene for chloramphenicol acetyl transferase (CAT) linked to the promoter regulatory domain from the HSV-1 alpha 4 gene results in production of substantial levels of CAT enzyme. Cotransfection of equal mole amounts of an alpha 27 containing plasmid with an alpha 4-CAT construct to CV-1 cells results in a greater than 85% inhibition of CAT activity. No significant inhibition of CAT activity was observed when transfection was done in HeLa cells, with the same concentrations tested. Intact alpha 27 structural genes were necessary to achieve inhibition since subgenomic fragments and restriction enzyme digested alpha 27 genes were not effective inhibitors. Cotransfection of alpha 27 genes to CV-1 cells also prevented alpha 0 as well as alpha 4 from mediating their trans-stimulation of the HSV thymidine kinase (tk) regulated CAT gene, B-CAT. This suggests that the alpha 27 gene product may down-regulate gene expression from alpha promoters.

Animals↗
PubMed1988

Application of a fibrinogen-thrombin-collagen-based hemostyptic agent in experimental injuries of liver and spleen.

FTCH is a recently developed material which consists of a collagen fleece containing fibrinogen, thrombin, and aprotinin integrated into its surface. FTCH is highly effective in sealing of tissues and in establishing hemostasis. We evaluated FTCH in experimentally produced liver (n = 6) and splenic (n = 12) injuries in 18 adult mongrel dogs. The stability of the parenchymal seal of the splenic injuries was tested by splenic tissue pressure elevation after temporary ligation of the splenic vein. No breakthrough bleeding occurred up to a parenchymal pressure of 16.3 +/- 5 mm Hg. Complete hemostasis was easily achieved in all animals before closure. When the dogs were re-explored postoperatively at intervals of either 14 or 30 days, there was no gross evidence of recurrent bleeding. Histologic examinations demonstrated a partially regenerated capsule covering an unspecific fibrovascular granulation tissue and progressive resorption of FTCH without significant inflammatory response. We conclude the following: FTCH provides adequate hemostatic control of experimental liver and splenic injuries. FTCH has excellent tissue compatibility and can be applied easily and safely to hemorrhaging parenchymal wounds. It will not replace adequate surgical techniques, but could be useful as a quickly available and easily applicable hemostatic means in diffuse or acute bleeding of liver and spleen.

Animals↗
PubMed1988

[Metaraminol in therapy of various forms of priapism].

A total of 19 patients (aged 17-66 years) with priapism received primarily conservative treatment in the form of aspiration of blood from the cavernous bodies and subsequent intracavernous (i.c.) administration of the alpha-adrenergic drug metaraminol. In 15 patients the priapism was due to i.c. injection of vasoactive agents; 1 patient each it had developed after hemodialysis, during oral prazosin medication, and in conjunction with Fabry's disease; and in 1 patient the etiopathogenesis was unknown. Treatment of priapism with metaraminol was successful in the first 15 patients and in 2 patients with priapism due to hemodialysis and oral prazosin medication. Therapy failed in long-lasting priapism associated with Fabry's disease and in priapism of unknown etiopathogenesis. Penile detumescence took place in the first 15 patients 3 min to 2.5 h after the injection of 2-4 mg metaraminol. Hemodialysis- and prazosin-linked priapism was treated with 5 and 2 mg metaraminol, respectively; in these patients erection subsided within 15 and 4 min after onset of therapy. In a further 2 patients in whom therapy had failed Al-Ghorab shunts were constructed, with the subsequent postoperative complication of erectile impotence. Injection of metaraminol must be carried out under strict supervision of the patient's circulatory system: doses of 4 mg metaraminol or more led to an increase in blood pressure and heart rate. In 15 patients with priapism induced by i.c. application of vasoactive agents, the analysis of blood gas parameters demonstrated a severe hypercapnia (70.3 +/- 10.0 mm Hg) and acidosis (pH 7.08 +/- 0.08) 5-10 h after the onset of erection, but severe hypoxia (37.0 +/- 16.6 mm Hg) was not found until erection had lasted for more than 10 h.(ABSTRACT TRUNCATED AT 250 WORDS)

Acid-Base Equilibrium↗
PubMed1987

The effectiveness of a fibrinogen-thrombin-collagen-based hemostatic agent in an experimental arterial bleeding model.

The hemostyptic agent used in this study is a recently developed material that consists of a collagen fleece containing fibrinogen, thrombin, and aprotinin integrated into its surface (FTCH) with excellent topical hemostyptic properties. The potential use of this substance for cardiovascular surgery was evaluated in a canine arterial bleeding model, which allowed comparison of the new agent with previously used pure collagen (CHF) as well as study of the hemostyptic under elevated blood pressure conditions. The results revealed that FTCH induced reliable hemostasis in 10-mm injuries of the canine hypogastric artery up to a systolic blood pressure of 260 mmHg, whereas bleeding control by CHF alone was impossible. To assess the long-term reliability of FTCH, the dogs were re-explored at intervals of 14 and 31 days after operation. At relaparotomy, the arteries were patent and there was no evidence of recurrent bleeding, thrombosis formation, or aneurysmatic changes. Histologic examinations showed well-healed vascular lesions covered by cell-depleted collagen tissue and a partially resorped hemostyptic. FTCH will not replace adequate surgical techniques but could be useful as a quickly available and easily applicable hemostatic means in otherwise uncontrollable diffuse or acute bleeding in cardiovascular surgery.

Animals↗
PubMed1987

[Value of nuclear magnetic resonance tomography in the staging of tumors of the urinary bladder].

The accuracy of magnetic resonance imaging (MRI) and computed tomography (CT) in the staging of bladder tumors was evaluated in 46 patients. In the T-staging MRI was superior to CT. With MRI 38 out of the 46 tumors were correctly staged into the four groups T0, T1-T3a, T3b and T4. With CT this classification was only possible in 28 cases. The main advantages of MRI were the capability for multiplanar imaging, which improved evaluation of the bladder base and the bladder dome, as well as a better differentiation between tumor recurrency and fibrosis. In the evaluation of adenopathy MRI and CT proved to be equal and demonstrated a sensitivity of 50%.

Carcinoma, Transitional Cell↗
PubMed1986

Use of iohexol in the radiographic diagnosis of ischemic bowel.

This study evaluates the use of iohexol as a radiographic diagnostic contrast agent in normal animals and those with experimental bowel ischemia and obstruction. Eighteen rats and 12 rabbits were gavaged with iohexol in a dose of 7.5 mL/kg using concentrations of 140 mg I/mL (isotonic with blood) or 300 mg I/mL. In addition, four rabbits had intraperitoneal iohexol injection and three were given gastrografin gavage. Experimental groups included normal bowel controls, bowel injury induced by ischemia and alcohol contact, bowel obstruction by ligature, and intraperitoneal injection. Serial abdominal radiographs and plasma concentrations of iohexol were obtained. Iohexol remained stable throughout the gastrointestinal tract, retained its intensity, and was well visualized up to four days after administration. Bowel images were fair at concentrations of 140 mg I/mL and excellent at 300 mg I/mL. Gastrografin caused bowel distention and poor visualization related to dilution. It also precipitated in the stomach. Iohexol was rapidly absorbed from the peritoneal cavity and excreted by the kidneys, without causing peritonitis. Rat plasma iohexol levels were three times controls in obstructed bowel and 80 times controls if there was mucosal injury without perforation. Rabbit peak plasma levels were 30 times greater following intraperitoneal injection than with gastric gavage. These observations suggest that iohexol may be useful as a gastrointestinal contrast agent. Measuring plasma iohexol levels may be helpful in the evaluation of suspected bowel ischemia or perforation in the clinical setting.

Animals↗
PubMed1985

Genetic linkage but independent expression of functional HSV-1 tk and mammalian aprt genes after cotransfer to L cells.

DNA-mediated gene transformation of mouse Ltk-aprt-hprt-cells was used to obtain stable, doubly selected transformants simultaneously expressing herpes virus thymidine kinase (TK) and mammalian adenine phosphoribosyltransferase (APRT). Cotransformants occurred at a frequency of 5 X 10(-6), a similar frequency for the transfer of the aprt marker has been previously observed. Isozyme and Southern blot analysis show that the TK and APRT expressed in these transformants resulted from gene transfer. For one stable cotransformant, [3H]thymidine [( 3H]TdR) selection against TK activity resulted in the loss of APRT activity as well, suggesting that these genes had become genetically linked together. Similarly selection against APRT expression resulted in the loss of a subset of the transferred herpes simplex virus tk genes. 5-Bromodeoxyuridine (BUdR) selected TK- variants differed from [3H]TdR selected TK- variants, in that they retained tk genes. However, BUdR-selected variants expressed full levels of APRT. Therefore, even though the transferred tk and aprt genes had become genetically linked together, they were, in this case, independently expressed since these cells were phenotypically TK- and APRT+.

Adenine Phosphoribosyltransferase↗
PubMed1984

Mutants of PC12 cells with altered cyclic AMP responses.

PC12 cells, derived from a rat pheochromocytoma, were mutagenized and selected in media containing agents known to elevate intracellular concentrations of cyclic AMP (cAMP). More than 40 clones were isolated by selection with cholera toxin or 2-chloroadenosine or both. The variants that were deficient in accumulating cAMP were obtained by using a protocol in which 1 microM 8-bromo-cAMP was included in addition to the agonist. Certain of these variants were partially characterized with respect to the site of altered cAMP metabolism. The profiles of adenylate cyclase activity responsiveness of certain variants to guanosine-5'-(beta, gamma-imido) triphosphate and to forskolin resembled those of UNC and cyc phenotypes of S49 lymphoma cells, which are functionally deficient in the GTP-sensitive coupling protein, Ns. Other variants were characterized by increased cyclic nucleotide phosphodiesterase activity at low substrate concentration. Diverse morphological traits were observed among the variants, but it was not possible to assign them to a particular cAMP phenotype. Two revertants of a PC12 mutant were isolated and observed to have regained a cellular cAMP response to 2-chloroadenosine and to forskolin. It is hoped that these PC12 mutants will have utility for defining cAMP-mediated functions, including any links to the action of nerve growth factor, in cells derived from the neural crest.

2-Chloroadenosine↗