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K Huber

Publications and source records attributed to K Huber.

At least 145 records · Page 8Linked to original sources

Restenosis following percutaneous revascularization--the potential role of thrombin and the thrombin receptor.

Thrombin is present at sites of vascular injury and elicits many effects which may contribute to neointimal growth. Further studies are needed to order to determine steps involved in thrombin-induced effects and to identify potential sites to regulate these effects. The failure of the Helvetica trial to demonstrate an effect of treatment with hirudin on restenosis may relate more to our inability to safely inhibit thrombin than to a lack of a role for thrombin in restenosis. A therapy which enables safe and effective control of thrombin-induced responses following vascular injury may yet prove effective at reducing restenosis following percutaneous coronary revascularization.

Angioplasty, Balloon, Coronary↗

[Inhibition of the renin-angiotensin system: ACE inhibitors and angiotensin II receptor blockers].

The renin-angiotensin system (RAS) plays an important role in blood pressure regulation and fluid homeostasis in people with and without hypertension. The ACE-inhibitors were the first of the RAS blocking agents to have a wide clinical acceptance. Several trials demonstrated their usefulness in the treatment of essential hypertension, congestive heart failure, post myocardial infarction and diabetic renal disease. The recent development of selective angiotensin II type 1 receptor II blockers offers the compelling concept of interfering on the receptor level without disruption of the prostaglandin and bradykinin biosystems. Losartan, the prototype of orally active angiotensin II type 1 receptor antagonists, has been shown to be safe and effective in control of elevated blood pressure and improvement of the abnormal hemodynamics in the patient with congestive heart failure. These early encouraging results have to be confirmed by studies translating the circulatory benefits into augmented end-organ protection and prolongation of life.

Angiotensin Receptor Antagonists↗

Purification and structural characterization of a flavoprotein induced by iron limitation in Methanobacterium thermoautotrophicum Marburg.

Cells of Methanobacterium thermoautotrophicum (strain Marburg) grown under iron-limiting conditions were found to synthesize a soluble polypeptide as one of the major cell proteins. This polypeptide purified as a homotetramer (170 kDa [subunit molecular mass, 43 kDa]) had a UV-visible spectrum typical of flavoproteins and contained 0.7 mol of flavin mononucleotide per mol of monomer. Quantitative analysis by immunoblotting with polyclonal antibodies indicated that the flavoprotein, which amounts to about 0.6% of soluble cell protein under iron-sufficient conditions (> or = 50 microM Fe2+), was induced fivefold by iron limitation (< 12 microM Fe2+). The flavoprotein-encoding gene, fprA, was cloned and sequenced. Sequence analysis revealed a well-conserved archaebacterial consensus promoter upstream of fprA, a flavodoxin signature within fprA, and 28% amino acid identity with a putative flavin mononucleotide-containing protein of Rhodobacter capsulatus which is found within an operon involved in nitrogen fixation. A possible physiological function for the flavoprotein is discussed.

Amino Acid Sequence↗

Effect of delayed specimen processing on cytomegalovirus antigenemia test results.

Blood samples held at either 4 degrees C or room temperature for 1 day had similar mean decreases in number of cytomegalovirus antigenemia-positive cells (52 to 55%) and similar false-negative test results (13 to 14%). After 2 days, samples held at 4 degrees C showed no further decline, whereas samples held at room temperature had a mean 81% decrease in positive cells, a 32% false-negative rate, and a more marked deterioration in cell morphology.

Antigens, Viral↗

Correlation of placental isoferritin with birth weight and time point of first contractions.

In a prospective study, the correlation between serum levels of placental isoferritin (PLF) and outcome of pregnancy was determined in 56 pregnant women. Women with contractions before the 36th week of pregnancy showed significantly lower PLF values compared with women with later contractions (p < 0.01). Furthermore, a strong correlation of PLF levels with birth weight was observed. In 11 (79%) cases with a birth weight < 2,500 g (group A), PLF values were < 10 U/ml whereas only 14% (6 of 42) of women with babies with a birth weight > 2,500 g (group B) revealed PLF levels < 10 U/ml. Because it has been shown previously that PLF has immunosuppressive properties, the secretion of PLF by the placenta could be responsible for the inhibition of the immunoreactivity of the maternal lymphocytes against the embryo. The strong correlation of low PLF values with preterm contractions and/or low birth weight recommends the determination of this protein as a marker for monitoring women with high risk pregnancies.

Adolescent↗

[Clinical significance of autologous transplantation with hematopoietic stem cells in leukemia and solid tumors].

Autologous Transplantation of hematopoietic tissue with frozen hematopoietic stem cells is increasingly used for leukemias and lymphomas, but also for some solid tumors. In the past, autotransplants have been performed with bone marrow as the source of hematopoietic stem cells. Circulating, blood derived hematopoietic stem cells, however, allow safe engraftment of all cell lines after supralethal chemo-radiotherapy. This survey describes the role of autologous stem cell transplantation in disorders that are currently in the center of clinical and scientific interest. This estimation is based on the proportion of protocols dealing with, and centering on, autologous stem cell transplantation in the context of treatment for leukemias and solid tumors ("Oncodisc", "PDQ").

Combined Modality Therapy↗

[Antihypertensive therapy and coronary heart disease: significance of the effect of concomitant cardiovascular risk factors].

Antihypertensive therapy as it was performed in the past has not provided the degree of protection against coronary heart disease as was originally predicted by epidemiologic evidence. An improvement of outcome of antihypertensive therapy can only be achieved if coronary risk is maximally reduced. Therefore, in treating hypertensive patients, one has to take care of a diligent search for the presence of other coexisting coronary risk factors, of a vigorous use of life-style modifications (nondrug therapy), and of a greater individual selectivity of antihypertensive agents for initial and chronic use, preferring those that may provide additional benefits for other coexisting coronary risks.

Antihypertensive Agents↗

Immunological aspects of subfertility.

No significant relationship between semen quality [determined by standard sperm analysis and sperm-cervical mucus (CM) interaction testing in vivo and in vitro] and the presence of antisperm antibodies (ASA) [determined using three different methods] in serum samples of males and/or females of subfertile partnerships was found. These circulating ASA were not associated with reduced fertility in prospective studies. On the other hand, ASA in semen, particularly those of the IgA class, significantly impaired the ability of spermatozoa to penetrate CM and the fertility prognosis of the couple. ASA in CM must also be considered as a severe infertility factor but are a very rare cause of poor mucus quality.

Adult↗

Fibrinogen, t-PA, and PAI-1 plasma levels in patients with pulmonary hypertension.

We measured fibrinogen levels as well as the fibrinolytic parameters tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor 1 (PAI-1) in plasma samples obtained at basal conditions and after stimulating the fibrinolytic system by venous occlusion (VO). Samples were taken from patients with primary pulmonary hypertension (PPH), with secondary thromboembolic pulmonary hypertension (SPHTH), with secondary pulmonary hypertension due to congenital heart disease with Eisenmenger's reaction (SPHCD), and from healthy control individuals (CON). Fibrinogen levels were not significantly different between the groups with PPH and SPHTH or between SPHCD and CON. The latter groups, however, exhibited significantly lower fibrinogen plasma levels compared with PPH or SPHTH (p < 0.01). Basal plasma levels of t-PA antigen, t-PA activity, and PAI-1 activity, respectively, did not differ significantly between the study groups. After VO, mean t-PA activity levels increased to a higher extent in control subjects compared with patients with PPH, or SPHTH, or SPHCD, with significant differences only between CON and SPHTH or CON and PPH (p < 0.03). Patients with PPH and SPHTH exhibit both increased fibrinogen plasma levels and a diminished fibrinolytic response compared with healthy subjects. Moreover, the fibrinogen plasma levels in patients with SPHCD are in normal range, and the fibrinolytic response is similar to CON compared with PPH and SPHTH, thus indicating the existence of a comparable prothrombotic situation in patients with PPH and SPHTH.

Adult↗

[The value of sequential CD 34 measurement for carrying out stem cell pheresis].

The recent significant improvement in disease-free survival in patients with certain haematological malignancies is due to high-dose chemotherapy and subsequent autologous bone marrow and/or stem cell transplantation. The proliferation and egression of stem cells into the peripheral blood must first be stimulated by defined chemotherapy and/or by administration of cytokines. However, the increase of circulating stem cells in peripheral blood is limited to only a few days. By immunologically analysing white blood cells for the expression of the surface antigen CD 34 it is possible to calculate the numbers of haematopoietic progenitor cells. Thus, besides monitoring haematopoietic recovery, the estimation of CD34+ cells in the peripheral blood can be used to indicate the optimal time point for stem cell collection. Two to four stem cell pheresis (one per day) may then yield sufficient stem cells to enable the safe and rapid reconstitution of haematopoiesis following supralethal chemotherapy.

Antigens, CD↗

[Thrombolysis of acute myocardial infarct: modifying factors of "door-to-needle time"].

Effect of thrombolytic treatment in acute myocardial infarction depends on several factors, most importantly on time to treatment. The door-to-needle time, the interval between admission and thrombolytic therapy initiation, may be one important factor. In a retrospective study, we analysed 151 patients who were admitted to our emergency department with acute myocardial infarction and who received thrombolytic treatment. We analysed door-to-needle time with respect to the factors age, gender, clinical symptoms, presence of prehospital ECG, presence of prehospital complications, day of admission, hour of admission, duration of pain and infarct site. We observed that the door-to-needle time is significantly shorter in those cases with a prehospital ECG (p < 0.001) or no prehospital complications (p < 0.001) as well as inferior infarction (p < 0.02). There was a trend towards a shorter interval in cases with typical chest pain plus autonomic symptoms (p = 0.05). No statistical significance was seen in respect to age, gender, day and hour of admission, and duration of pain. Door-to-needle time with respect to thrombolytic treatment seems to depend on several factors in the preclinical field. Improvement of prehospital diagnosis and prevention of preclinical complications might result in faster thrombolytic treatment of the patient after arrival at the emergency department.

Adult↗

[Immunophenotyping of leukemia: overview].

Leukaemias that cannot be classified properly by morphological/cytochemical parameters may be diagnosed clearly by immunophenotyping. In this way, the neoplastic cells can be designated to either the myeloid or the lymphatic line of blood cells. Furthermore, myeloid leukaemias can be subtyped immunophenotypically in cases of type M0, M6, and M7, leukaemias, as well as in cases of mixed lineage or undifferentiated leukaemias. In patients with non-Hodgkin-lymphomas the cells can be characterized as being of B- or T-cell origin, and their activational or proliferative state can be assessed. Notably with acute lymphatic leukaemias, the prodigious therapeutical progress over the past years must be attributed to the refined definition of subtypes by immunophenotyping.

Antibodies, Monoclonal↗

[The prognostic factors following the simultaneous radiochemotherapy of anal canal carcinoma in a multicenter series of 139 patients].

PURPOSE: Evaluation of prognostic variables, results and toxicity after chemo-radiation (CRT) of anal canal carcinoma (ACC). MATERIAL AND METHODS: Between 1982 and 1992, 139 patients with epidermoid carcinoma of the anal canal were treated by radiation and chemotherapy with 5-fluorouracil (5-Fu) and mitomycin C (MMC). 99 patients belonged to a prospectively designed trial (50 Gy, 2 courses of chemotherapy) and 40 to a historical control group (40 Gy, 1 course of chemotherapy). The female/male ratio was 116/23. Median age was 62 years. Staging (UICC 1987): T1: 16.5%; T2: 49%; T3: 23%; T4: 9.4%; unknown: 2.1%. Abnormal regional nodes were present in 15% of the patients. HISTOLOGY: Squamous cell carcinoma: 68%; cloacogenic carcinoma: 31%; unknown: 1%. External beam radiation (ERT) was given to the primary tumour including perirectal, inguinal and iliac nodes by a 3 to 4 field box technique (50 patients) or parallel opposed fields (89 patients). Median single fraction and total dose were 1.8 Gy and 50 Gy. An additional boost to the involved sites was delivered by ERT (32 cases; median dose 16 Gy) or interstitial brachytherapy (BT) in 28 cases with a median dose 14 Gy. 84 patients (60%) received 2 or more cycles, 50 patients (36%) 1 cycle, 5 patients (4%) no chemotherapy. RESULTS: The survival rate, NED-survival rate and local tumour control rate were 78%, 64% and 69% at 5 years. Anorectal function was retained in 94 of 139 patients (68%). Multivariate analysis indicated that T-stage (p = 0.037) and belonging to the historical control group (p = 0.003) were significant variables for local tumour control. T-stage was a marginally significant factor (p = 0.09) for NED-survival. Acute toxicity of grade 3 and 4 (WHO) was observed in 36%, severe late toxicity (grade 3 Eschwege) in 3% of the patients. CONCLUSIONS: CRT with 2 courses 5-FU, MMC and ERT to a total dose of 45 to 50 Gy is a safe and effective treatment for ACC. Intensification of treatment is recommended in advanced stages T3/4.

Adult↗

Clinical value of determination of urokinase-type plasminogen activator antigen in plasma for detection of colorectal cancer: comparison with circulating tumor-associated antigens CA 19-9 and carcinoembryonic antigen.

We determined urokinase-type plasminogen activator antigen (u-PA), gastrointestinal cancer-associated antigen (CA 19-9), and carcinoembryonic antigen (CEA) in the plasma of patients with colorectal cancer at the time of clinical tumor detection and in a group of patients with Crohn's disease and analyzed the specificity of these tumor markers. u-PA, CA 19-9, and CEA were indicative for colorectal cancer in 75.5%, 51.5%, and 51.5% of tumor patients, respectively, with a specificity of 79.3%, 94%, and 97.5%. Sensitivity increased when two or all three markers were determined in identical blood samples, whereby a combination of u-PA and CEA exhibited the highest sensitivity value (90.9%) as compared to the combinations of u-PA and CA 19-9 or CA 19-9 and CEA. The use of all 3 markers did not lead to further increased sensitivity. False negative results were obtained in 3 of 32 cancer patients (9.1%, using one of 3 markers as indicative for malignant disease). These results indicate the benefit of multiparametric tumor marker analyses including u-PA antigen for the diagnosis of colorectal cancer.

Adult↗

Influence of cardiac output on peak t-PA plasma levels in patients receiving thrombolytic therapy with recombinant tissue-type plasminogen activator--correlation with patency rate.

We studied 35 consecutive patients with short onset of myocardial infarction who underwent thrombolytic therapy with rt-PA at a standard dosage regimen of 100 mg rt-PA total (10 mg given as a bolus followed by 50 mg, 20 mg and 20 mg per hour for 3 hours). These patients were monitored for t-PA antigen and t-PA activity and PAI-1 activity plasma levels during rt-PA infusion. Success or failure of thrombolytic therapy was evaluated by non-invasive criteria (early plasma creatine kinase peaks, early peak plasma myoglobin values, and electrocardiographic criteria) as well as by means of coronary angiography at the fourth day after thrombolytic treatment. In 24 (68.6%) of these patients a success of thrombolytic therapy could be established by these criteria, while 11 patients did not respond to thrombolytic therapy. Fifteen patients (14 responders and one non-responder) had to be excluded from the further evaluation because in these patients clinical laboratory data obtained upon admission before initiation of thrombolytic therapy were not complete. Therefore, 20 patients (10 responders and 10 non-responders) could further be analysed. The two groups of patients were not significantly different in body weight, body weight index, age, gender, liver or kidney functional parameters as determined before initiation of the thrombolytic therapy. Furthermore, PAI-1 plasma levels before initiation of thrombolytic therapy were not significantly different in the two groups, as were rt-PA dosage per body weight or body weight index.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗