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H Huber

Publications and source records attributed to H Huber.

At least 109 records · Page 6Linked to original sources
PubMed1997

Reclassification of the crenarchael orders and families in accordance with 16S rRNA sequence data.

A phylogenetic analysis of all validly published members of the Crenarchaeota, including several new isolates from our laboratory, suggests three orders within this archaeal kingdom. The Thermoproteales consist of both the rod-shaped, hyperthermophilic, neutrophilic representatives of the Thermoproteaceae and the members of the new family Thermofilaceae. The Sulfolobales harbor all thermoacidophilic, coccoid organisms. The neutrophilic, hyperthermophilic cocci are members of a new order tentatively named "Igneococcales." This order comprises two families, the Desulfurococcaceae, characterized by maximal growth temperature of up to 100 degrees C, and the new family Pyrodictiaceae, for which optimal growth occurs at temperatures above 100 degrees C.

Archaea↗
PubMed1997

Organic solutes in hyperthermophilic archaea.

We examined the accumulation of organic solutes under optimum growth conditions in 12 species of thermophilic and hyperthermophilic Archaea belonging to the Crenarchaeota and Euryarchaeota. Pyrobaculum aerophilum, Thermoproteus tenax, Thermoplasma acidophilum, and members of the order Sulfolobales accumulated trehalose. Pyrococcus furiosus accumulated di-myo-inositol-1,1(prm1)(3,3(prm1))-phosphate and (beta)-mannosylglycerate, Methanothermus fervidus accumulated cyclic-2,3-bisphosphoglycerate and (beta)-mannosylglycerate, while the only solute detected in Pyrodictium occultum was di-myo-inositol-1,1(prm1)(3,3(prm1))-phosphate. Methanopyrus kandleri accumulated large concentrations of cyclic-2,3-bisphosphoglycerate. On the other hand, Archaeoglobus fulgidus accumulated three phosphorylated solutes; prominent among them was a compound identified as di-glycerol-phosphate. This solute increased in concentration as the salinity of the medium and the growth temperature were raised, suggesting that this compound serves as a general stress solute. Di-myo-inositol-1,1(prm1)(3,3(prm1))-phosphate accumulated at supraoptimal temperature only. The relationship between the accumulation of unusual solutes and high temperatures is also discussed.

Journal Article↗
PubMed1997

Adjunctive interferon-alpha-2c in stage IIIB/IV small-cell lung cancer: a phase III trial.

Preliminary studies have shown bioactivity of interferons (IFNs) in the treatment of small-cell lung cancer (SCLC). The aim of the present study was to determine whether, in patients with advanced SCLC, a combination of recombinant IFN-alpha-2c and standard induction chemotherapy would improve response rates and survival at acceptable toxicity. Of the 85 patients recruited by 11 centres in Austria, 77 were evaluable for response after induction therapy; of these, 43 were randomized to receive the combined treatment (three cycles each of cyclophosphamide/vincristine/doxorubicin and cisplatin/etoposide plus subcutaneous IFN-alpha-2c), and 34 received chemotherapy alone. After the induction phase, patients in the IFN arm had higher rates of complete (30 vs 15%) and partial remission (42 vs 29%) than those who received chemotherapy alone. Accordingly, there was a lower rate of progressive disease in the interferon arm (21 vs 44%; p < 0.05). Whilst there were no significant differences in time to progression (7.6 vs 5.4 months) patients in the IFN arm survived longer than those in the chemotherapy arm (p < 0.02). Six of the patients treated with IFN (14%) survived for more than 2 yrs, whereas none in the chemotherapy arm did. We conclude that the addition of interferon-alpha-2c to induction chemotherapy may improve response rates and survival in advanced small-cell lung cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

Involvement of P-glycoprotein in the transmembrane transport of interleukin-2 (IL-2), IL-4, and interferon-gamma in normal human T lymphocytes.

The physiological role of the multidrug resistance P-glycoprotein (P-gp), which is expressed by normal human T lymphocytes, is still largely unknown. To investigate whether or not P-gp is involved in the transport of cytokines, peripheral blood lymphocytes were stimulated with phytohemagglutinin (PHA) in the absence or presence of P-gp inhibitors, and concentrations of cytokines (interleukin-2 [IL-2], IL-4, IL-6, interferon-gamma [IFN-gamma]) in the supernatants of these cultures were quantitated by enzyme-linked immunosorbent assay. P-gp inhibitors included verapamil (Ver), tamoxifen (Tmx), and the P-gp specific monoclonal antibody UIC2. Release of IL-2 was significantly suppressed by these inhibitors at concentrations that were also effective in blocking efflux of Rhodamine-123 from normal T lymphocytes. IL-2 mRNA expression in lymphocytes was not different between PHA control and the cultures with P-gp inhibitors. Ver and Tmx did not interfere with T-cell activation as determined by CD25 and CD69 expression. In a nonhematological model, the P-gp expressing HCT-8 adenocarcinoma cell line, exogenously added IL-2 was shown to exert an inhibitory effect on P-gp mediated Rhodamine-123 efflux. In addition, transepithelial transport of IL-2 by electrophysiologically tight and polarized HCT-8 monolayers was examined. A time-dependent flux of IL-2 across dense monolayers, which was partially inhibited by Ver, was observed. We also investigated whether or not P-gp inhibitors suppressed release of other cytokines produced by activated T cells (IL-4, IL-6, IFN-gamma). Release of IL-4 and IFN-gamma was significantly inhibited by Ver, Tmx, and UIC2; however, release of IL-6 remained unaffected. These data show P-gp mediated transmembrane flux of IL-2 in T lymphocytes and HCT-8 cells. We conclude that P-gp participates in the transport of cytokines (IL-2, IL-4, and IFN-gamma) in normal peripheral T lymphocytes.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1996

[The latency period between exposure and the symptoms in allergy to natural latex. Suggestions for prevention].

BASIC PROBLEM AND OBJECTIVE OF STUDY: Among persons working in the health care system allergies caused by natural rubber latex (NRL) are more common than among the general population, because the frequent use of latex gloves and other latex articles may cause sensitisation. A retrospective study was undertaken to determine the period before such an allergy occurs. PATIENTS AND METHODS: 63 patients (53 women and 10 men; mean age 31.3 +/- 8.3 years) with symptoms of type 1 (immediate response; IgE-mediated) allergy to NRL filled in a special questionnaire asking, among other items, about occupational history, duration and frequency of contact with latex gloves, as well as the course of occupational or other symptoms. All but five of the group had been in their job for less than 15 years. A prick test with 21 ubiquitous environmental allergens was performed on 62 of the patients. RESULTS: Two thirds of the patients had atopy. First symptoms of an allergy to latex developed at an average of 5 years (58.7 +/- 59.3 months) after starting work involving contact with latex products. In 59 persons the first symptoms were contact urticaria, in some together with rhinitis or dyspnea. The interval until onset of symptoms relating to the lower respiratory tract averaged a further 25.3 +/- 34.6 months. Symptoms developed earlier in patients with atopy than in those without (51.9 +/- 54.3 vs 76 +/- 69 months). CONCLUSIONS: The use of powdered natural rubber latex gloves should be discontinued to prevent the increasing incidence of sensitization to aerogenic latex and to protect those already sensitized from developing allergic bronchial asthma.

Adult↗
PubMed1996

Small G proteins of two green algae are localized to exocytic compartments and to flagella.

The Ypt/Rab proteins are small GTPases, which belong to the Ras superfamily and have been shown to be involved in endo- and exocytosis in mammalian cells and yeast. Using affinity-purified antibodies specific for four Ypt proteins, namely Ypt1p, Ypt4p, Ypt5p and Ypt6p, of the multicellular green alga Volvox carteri (YptVp) and its close unicellular relative Chlamydomonas reinhardtii (YptCp), we examined the abundance of the corresponding antigens during the asexual life cycle of Volvox, and their intracellular localization. The YptV proteins were found in all stages throughout the asexual life cycle and are tightly associated with intracellular membranes. Indirect immunofluorescence revealed that YptV4p, YptV5p and YptV6p are present in perinuclear regions of the cell, indicating an association with the Golgi region. Golgi localization of YptV4p and YptV6p in Volvox was confirmed by immunogold electron microscopy. In contrast, we found Ypt1p associated with the contractile vacuole in both V. carteri and C. reinhardtii. Furthermore, the YptV proteins were also detected along the entire length of the flagella of somatic Volvox cells. This flagellar location was substantiated by western blot analysis of extracts prepared from isolated flagella of both algae. While localization to exocytic compartments is in agreement with the established Ypt/Rab function in intracellular vesicle transport of eukaryotic cells, presence in the algal flagellum is the first hint of a possible role for small G proteins also in motility organelles.

Blotting, Western↗
PubMed1996

A clinical report for distalizing maxillary molars by using super-elastic wires.

A class II/2 malocclusion with considerable amount of crowding was treated non-extraction by distalization. The upper molars were moved posteriorly with the use of superelastic wires. The orthodontic therapy-mode is presented and the results are discussed. This treatment approach shows another use of superelastic wires.

Adult↗
PubMed1996

Ferroglobus placidus gen. nov., sp. nov., A novel hyperthermophilic archaeum that oxidizes Fe2+ at neutral pH under anoxic conditions.

A novel coccoid, anaerobic, Fe2+-oxidizing archaeum was isolated from a shallow submarine hydrothermal system at Vulcano, Italy. In addition to ferrous iron, H2 and sulfide served as electron donors. NO3- was used as electron acceptor. In the presence of H2, also S2O32- could serve as electron acceptor. The isolate was a neutrophilic hyperthermophile that grew between 65 degrees C and 95 degrees C. It represents a novel genus among the Archaeoglobales that we name Ferroglobus. The type species is Ferroglobus placidus (DSM 10642).

Archaea↗
PubMed1996

Interferon alpha-2c therapy of patients with chronic myelogenous leukemia: long-term results of a multicenter phase-II study. Austrian Biological Response Modifier (BRM) Study Group.

In a prospective multicenter phase-II trial 80 patients with Philadelphia (Ph)-positive chronic myelogenous leukemia (CML) were treated with recombinant interferon (IFN) alpha-2c, administered subcutaneously at an absolute dose of 3.5 megaunits (MU)/day. Complete hematological remission was achieved in 29 (39%) and partial hematological remission in 26 (35%) of the 74 patients evaluable for response. Major cytogenetic responses were observed in ten (13%) and minor cytogenetic responses in 11 patients (15%). Median duration of cytogenetic response was 33 months (range, 2-90); relapses were seen in all of the 11 patients with minor and in three of the ten patients with major cytogenetic responses. Median survival estimates for pretreated (n = 19) and untreated (n = 58) patients were 51 months (95% confidence interval [CI], 30-72) and 77 months (95% CI, 43-111), and the survival probabilities at 5 years were 45% and 54% for the two groups, respectively. Hematological response after 3 months of treatment demonstrated a clear-cut discriminative capacity with 5-year survival probabilities of 100%, 67% and 24% for patients achieving CHR (n = 6), PHR (n = 34), and less than PHR (n = 35), respectively. Landmark analysis at 12, 18, and 24 months after start of IFN therapy and an analysis treating time to cytogenetic response as a time-dependent covariate showed that cytogenetic response was associated with longer survival. The impact of a low-dose IFN regimen on survival in CML patients is unclear and requires further clarification by randomized clinical trials. Early hematological and cytogenetic response to IFN-alpha treatment identifies patients with a favorable long-term prognosis.

Adolescent↗
PubMed1996

Vinorelbine-induced neurotoxicity in patients with advanced breast cancer pretreated with paclitaxel--a phase II study.

Vinorelbine (VNB) shows high antitumoral activity in advanced breast cancer due to its high affinity for mitotic tubulin and differs from the other vinca alkaloids with regard to its low degree of neurotoxicity because of its low affinity for axonal tubulin. Preclinical data show the existence of different binding sites on tubulin for vinca alkaloids and paclitaxel (P), suggesting a lack of cross-resistance. Thus, VNB was chosen eligible for a phase II study to evaluate both the therapeutic efficacy and the toxicity of VNB in patients (pts) with advanced breast cancer failing first- or second-line chemotherapy with P. A total of 14 pts with advanced breast cancer pretreated with P were entered into the study. Therapy consisted of VNB at 30 mg/m2 diluted in 500 ml of normal saline given over 30 min after a minimal interval of 4 weeks since the last application of P. For the first four cycles, injections were repeated at 2-week intervals; thereafter they were repeated at 3-week intervals until evidence of progressive disease or severe toxicity developed. All but one pt was considered assessable for response and all pts were evaluable for toxicity. No objective response was observed; two pts showed no change in their disease. In four pts therapy had to be stopped because peripheral neurotoxicity increased from a pretherapeutic level after therapy with P from National Cancer Institute Common Toxicity Criteria (NCI-CTC) grade 1 (n = 3) and 2 (n = 1) to neurotoxicity grade 3 after 1, 2 (n = 2), and 3 cycles of therapy with VNB, respectively. In addition, constipation of grade 2 occurred in 10 pts. Hematologic toxicity was negligible. No other evaluable toxicity exceeded NCI-CTC grade 1. Both observations of this study, the complete resistance to VNB and the increase in peripheral neuropathy, let us assume the existence of a preclinically not anticipated but clinically relevant cross-resistance between these two spindle poisons and the presence of common functional targets. Therefore, P-pretreated pts should be excluded from consecutive VNB-containing therapies.

Adult↗
PubMed1996

Fluoride released from orthodontic bonding agents alters the enamel surface and inhibits enamel demineralization in vitro.

In this study, we examined two fluoride-releasing orthodontic agents in respect to fluoride release, enamel demineralization inhibition, as well as alterations observed on the enamel surface after their use. Fluoride release was found to occur in the highest concentrations within the first 24 hours for both materials examined. After this period, a dramatic decline in fluoride release was observed in both adhesives, and after 90 days no fluoride was detectable. Both fluoride-releasing materials showed significant differences on enamel demineralization around the brackets when compared with a conventional adhesive, and the agent with the initial higher amounts of fluoride release showed the best results. Scanning electron microscopy of the enamel surface revealed particle depositions of microglobular form, after the examined adhesives were used. These particles most likely represent deposition of calcium fluoride, a salt with clearly cariostatic properties. The results of this in vitro study show that certain fluoride-releasing orthodontic bonding systems may provide an additional degree of safety against caries susceptibility in patients with fixed appliances for a limited period.

Adhesives↗
PubMed1996

Genes related to growth and invasiveness are repressed by sodium butyrate in ovarian carcinoma cells.

Down-regulation of oncogene expression is one of the hallmarks of the process whereby transformed cells are forced into differentiation and/or growth arrest by potent inducers and therefore can represent an interim end point in cancer treatment. The differentiation inducer sodium butyrate (NaB) arrested growth of N.1 ovarian carcinoma cells and repressed expression of cyclin D1/prad1 and the invasiveness-related protease plasminogen activator-urokinase (plau). This was accompanied by the acquisition of a differentiated morphology, all of which characteristics were maintained as long as N.1 cells were exposed to the inducer. In accordance with a differentiated phenotype was the finding that fibronectin expression was increased significantly. Recently, it was shown that NaB represses the transcription factor c-myc by blocking Ca2+ signals and modulating serine threonine kinase activity. We wanted to investigate NaB-mediated interference on signals contributing to the expression on prad1, plau and growth arrest-specific 6 (gas6). Protein kinase A (PKA) inactivation de-repressed prad1 and plau transcript levels. NaB had onlygeneral but no specific influence on PKA-modulated prad1 and plau expression however. Protein kinase C activation up-regulated plau transcript levels, but not that of prad1. Prad1 expression seemed to depend on Ca2+-triggered signals. Constitutive plau expression was insensitive to additional Ca2+-mediated signals, but it became responsive upon NaB treatment.

Adenylyl Cyclases↗
PubMed1996

[Molecular biology of tobacco smoke associated neoplasia].

Adducts, formed by carcinogens of tobacco smoke with DNA, can be detected by means of molecular techniques and are used as marker of internal exposure. Carcinogen-DNA adducts produce specific mutations in tumor-suppressor genes (e.g. p53) and oncogenes (e.g. ras), which can be involved in tumor initiation or in later stages of tumor progression (e.g. evolution of an invasive phenotype). Benzo(a)-pyrene, an important carcinogen of tobacco smoke, induces GT transversions, as demonstrated in in vitro systems and animal models. Mutations in the p53- or ras-gene are more common in human tumors of the lung, head and neck, bladder and pancreas in smokers than in non-smokers. Molecular biology of cancer gains increasing significance in clinical practice since 1.) the presence of certain mutations confers an unfavorable prognosis to malignant disease (e.g. ras mutations in lung cancer), 2.) ras and p53 mutations often occur early during tumor development and can thus facilitate diagnosis of malignant disease, and 3.) minimal residual disease can be detected using molecular techniques. After resection of cancer of the head and neck, tumor recurred more frequently in patients with no evidence of residual disease as assessed by pathohistologic criteria than in patients with no evidence of residual disease as evaluated by p53 immunostaining.

Carcinogens↗
PubMed1995

Bidirectional interactions between the estrogen receptor and the cerbB-2 signaling pathways: heregulin inhibits estrogenic effects in breast cancer cells.

The responsiveness of estrogen receptor (ER)-positive breast cancer to endocrine therapy is frequently reduced in cells over-expressing c-erbB-2. Stimulation of ER suppresses c-erbB-2, indicating that estrogen controls the activity of c-erbB-2. Heregulin (HRG) has been described to bind to c-erbB-3/c-erbB-4 and to stimulate c-erbB-2. Here we describe the effects of HRG on cell growth and on ER and c-erbB-2 expression in breast cancer cell lines containing distinct levels of c-erbB-2 and ER (BT-474: c-erbB-2 , ER+; MDA-MB-361: c-erbB-2++, ER++; MCF-7: c-erbB-2+, ER ). Proliferation of estrogen-stimulated, c-erbB-2 and ER-positive cells is inhibited by HRG in a dose-dependent manner. In addition, HRG dose-dependently inhibits ER expression. Estrogen, however, inhibits c-erbB-2. Estrogen-mediated down-regulation of c-erbB-2 is most pronounced in MCF-7 but weaker in BT-474. In the latter cells HRG efficiently blocks the estrogenic effect on c-erbB-2. In MCF-7 cells, however, the inhibition of c-erbB-2 cannot be completely reverted by HRG. This modulation occurs in all 3 cell lines at protein, RNA and transcriptional levels, suggesting that the activity of the c-erbB-2 promoter, which contains an estrogen-responsive region, is affected by HRG. The intensity of the mutual inhibition between the HRG/c-erbB-2 and the estrogen/ER system depends on the relative levels of ER and c-erbB-2 expression in the respective cell lines.

Antineoplastic Agents↗
PubMed1995

Interphase fluorescence in situ hybridization identifies chromosomal abnormalities in plasma cells from patients with monoclonal gammopathy of undetermined significance.

Karyotypic studies in patients with monoclonal gammopathy of undetermined significance (MGUS) have been hampered by a low percentage of bone marrow plasma cells (BMPC), which are predominantly nonproliferating. By combining cytomorphology and interphase fluorescence in situ hybridization (FISH) we investigated whether or not chromosomal abnormalities occur in BMPC from patients with MGUS. Studying chromosomes 3, 7, 11, and 18, which we found to be frequently aneuploid by FISH in multiple myeloma (MM), we observed three hybridization signals for one of these chromosomes 3 were most common, occurring in 38.9% of patients, followed by gains of chromosomes 11 (25%), 7 (16.7%), and 18 (5.6%) Among BMPC, the frequency of aneuploid cells was 18.9% +/- 13.9% (mean +/- SD) for chromosome 3, 22.3% +/- 9.2% for chromosome 11, 23.2% +/- 22.0% for chromosome 7, and 6.1% +/- 2.3% for chromosome 18. In five patients, chromosomal abnormalities were shown to be restricted to BMPC expressing cytoplasmic immunoglobulins corresponding to the serum paraprotein. No gain of hybridization signals was observed in normal and reactive plasma cells. In one patient with MGUS, metaphase cytogenetics revealed one abnormal metaphase with 47, XY, +4, and trisomy 4 was also demonstrated in a subpopulation of BMPC by interphase FISH. FISH results from patients with MGUS and newly diagnosed MM at stage IA (n = 14) indicated that aberrations involving > or = 2 chromosomes occurred significantly more often in early stage MM (P < .01). With respect to clinical and laboratory features, MGUS patients with and without chromosomal abnormalities were indistinguishable. Our results indicate that MGUS already has the chromosomal characteristics of a plasma cell malignancy.

Adult↗