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41.
Weide B Eigentler TK Pflugfelder A Leiter U Meier F Bauer J Schmidt D Radny P Pföhler C Garbe C 《Cancer immunology, immunotherapy : CII》2011,60(4):487-493
Systemic high-dose interleukin-2 (IL-2) treatment achieves long-term survival in a subset of advanced patients with melanoma.
As we reported previously, intratumoral IL-2 induced complete local responses in more than 60% of melanoma patients. This
study aimed to analyze the long-term outcome of 72 patients treated in two prior trials. Melanoma patients (49 stage III,
23 stage IV) with injectable metastases received intratumoral IL-2 injections thrice weekly at individually escalated doses
(median duration, 6.5 weeks; median total IL-2 dose, 72 MIU; median number of injected metastases, 10). The observed 2-year
overall survival rates were 95.5% for stage III patients with cutaneous metastases only (stage IIIB), 72% for those with combined
cutaneous and lymph node involvement (stage IIIC), 66.7% for stage IV patients with disease limited to distant soft-tissue
metastases (stage IV M1a), and 9.1% for those with visceral metastases (stage IV M1b and stage IV M1c). Thirty patients who
reported recurrence of unresectable distant metastases subsequently received chemotherapy in the further course of disease
and showed an overall response rate of 36.7% (16.7% complete responses, 20% partial responses). A high total dose of IL-2
and a dacarbazine/temozolomide-based chemotherapy regimen were variables correlated with a clinical response. In conclusion,
patients with cutaneous metastasis without lymph node involvement in stage III and with soft-tissue metastasis without visceral
involvement in stage IV showed unexpected favorable survival rates after intratumoral treatment with IL-2. Furthermore, the
intratumoral IL-2 treatment seemed to be associated with increased complete and partial responses in subsequent chemotherapies. 相似文献
42.
Porro D Gasser B Fossati T Maurer M Branduardi P Sauer M Mattanovich D 《Applied microbiology and biotechnology》2011,89(4):939-948
Recombinant DNA (rDNA) technologies allow the production of a wide range of peptides, proteins and metabolites from naturally
non-producing cells. Since human insulin was the first heterologous compound produced in a laboratory in 1977, rDNA technology
has become one of the most important technologies developed in the 20th century. Recombinant protein and metabolites production
is a multi-billion dollar market. The development of a new product begins with the choice of the cell factory. The final application
of the compound dictates the main criteria that should be taken into consideration: (1) quality, (2) quantity, (3) yield and
(4) space time yield of the desired product. Quantity and quality are the most predominant requirements that must be considered
for the commercial production of a protein. Quantity and yield are the requirements for the production of a metabolite. Finally,
space time yield is crucial for any production process. It therefore becomes clear why the perfect host does not exist yet,
and why—despite important advances in rDNA applications in higher eukaryotic cells—microbial biodiversity continues to represent
a potential source of attractive cell factories. In this review, we compare the advantages and limitations of the principal
yeast and bacterial workhorse systems. 相似文献
43.
44.
Lisa Klug Pablo Tarazona Clemens Gruber Karlheinz Grillitsch Brigitte Gasser Martin Trötzmüller Harald Köfeler Erich Leitner Ivo Feussner Diethard Mattanovich Friedrich Altmann Günther Daum 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2014,1841(2):215-226
The methylotrophic yeast Pichia pastoris is a popular yeast expression system for the production of heterologous proteins in biotechnology. Interestingly, cell organelles which play an important role in this process have so far been insufficiently investigated. For this reason, we started a systematic approach to isolate and characterize organelles from P. pastoris. In this study, we present a procedure to isolate microsomal membranes at high purity. These samples represent endoplasmic reticulum (ER) fractions which were subjected to molecular analysis of lipids and proteins. Organelle lipidomics included a detailed analysis of glycerophospholipids, fatty acids, sterols and sphingolipids. The microsomal proteome analyzed by mass spectrometry identified typical proteins of the ER known from other cell types, especially Saccharomyces cerevisiae, but also a number of unassigned gene products. The lipidome and proteome analysis of P. pastoris microsomes are prerequisite for a better understanding of functions of this organelle and for modifying this compartment for biotechnological applications. 相似文献
45.
Background
Determination and quantification of nucleic acid components in a mixture is usually accomplished by microarray approaches, where the mixtures are hybridized against specific probes. As an alternative, we propose here that a single sequencing reaction from a mixture of nucleic acids holds enough information to potentially distinguish the different components, provided it is known which components can occur in the mixture. 相似文献46.
Simple sequences (or microsatellites) are stretches of monotonous repetitions of short (1–5 bp) nucleotide motifs that are distributed across the whole genome in eukaryotes. They are probably generated by slippage during replication and their primary mutation rate seems to be controlled predominantly by the efficiency of the mismatch repair system. Although most mutations in simple sequence loci appear to be neutral, some mutations in particular stretches have been implicated as having a role in human genetic diseases. 相似文献
47.
J. Mattanovich M. Ehrenhöfer C. Schafellner M. Tausz & E. Führer 《Journal of Applied Entomology》2001,125(8):425-431
Bark beetles, especially Ips typographus L. represent a severe biotic threat for spruce ( Picea abies [L.] Karst.) at low altitudes in Europe. We compared sulphur (total S, SO4 2− , glutathione, cysteine, methionine), nitrogen (total N, NO3 − , total protein, free amino acids), carbon, total phosphorus and PO4 3− , tree vigour index (TVI) and water content of the phloem after felling, and their dependent changes (tdc) with the breeding success of I. typographus . Twenty trees were classified according to age (34/90 years) and crown density (high/intermediate/low). Water content was higher in young trees than in old trees, higher in the crown than at breast height, and decreased significantly within the 8-week study period. In old trees, breeding success, length of mother galleries and SO4 2− were significantly higher, while total protein, NO3 − and water content were significantly lower than in young trees. Trees with intermediate crown density provided the best breeding success for I. typographus and had significantly higher arginine content and C/N ratio as well as low amounts of phosphate and glutamine. During the period of bark beetle breeding, total sulphur, glutathione, protein, NO3 − , aspartate, glutamine, glutamate, arginine and γ-aminobutyrate decreased significantly. The results support previous investigations that I. typographus develops best in physiologically weakened trees. 相似文献
48.
Minoska Valli Michael Sauer Paola Branduardi Nicole Borth Danilo Porro Diethard Mattanovich 《Applied microbiology》2005,71(3):1515-1521
Intracellular pH has an important role in the maintenance of the normal functions of yeast cells. The ability of the cell to maintain this pH homeostasis also in response to environmental changes has gained more and more interest in both basic and applied research. In this study we describe a protocol which allows the rapid determination of the intracellular pH of Saccharomyces cerevisiae cells. The method is based on flow cytometry and employs the pH-dependent fluorescent probe carboxy SNARF-4F. The protocol attempts to minimize the perturbation of the system under study, thus leading to accurate information about the physiological state of the single cell. Moreover, statistical analysis performed on major factors that may influence the final determination supported the validity of the optimized protocol. The protocol was used to investigate the effect of external pH on S. cerevisiae cells incubated in buffer. The results obtained showed that stationary cells are better able than exponentially grown cells to maintain their intracellular pH homeostasis independently of external pH changes. Furthermore, analysis of the intracellular pH distribution within the cell populations highlighted the presence of subpopulations characterized by different intracellular pH values. Notably, a different behavior was observed for exponentially grown and stationary cells in terms of the appearance and development of these subpopulations as a response to a changing external pH. 相似文献
49.
Summary In the area of Haidach (Northern Calcareous Alps, Austria), coral-rudist mounds, rudist biostromes, and bioclastic limestones
and marls constitute an Upper Cretaceous shelf succession approximately 100 meters thick. The succession is part of the mixed
siliciclasticcarbonate Gosau Group that was deposited at the northern margin of the Austroalpine microplate.
In its lower part, the carbonate succession at Haidach comprises two stratal packages that each consists, from bottom to top,
of a coral-rudist mound capped by a rudist biostrome which, in turn, is overlain by bioclastic limestones and, locally, marls.
The coral-rudist mounds consist mainly of floatstones. The coral assemblage is dominated by Fungiina, Astreoina, Heterocoeniina
andAgathelia asperella (stylinina). From the rudists, elevators (Vaccinites spp., radiolitids) and recumbents (Plagioptychus) are present. Calcareous sponges, sclerosponges, and octocorals are subordinate. The elevator rudists commonly are small;
they settled on branched corals, coral heads, on rudists, and on biolastic debris. The rudists, in turn, provided settlement
sites for corals. Predominantly plocoid and thamnasteroid coral growth forms indicate soft substrata and high sedimentation
rates. The mounds were episodically smothered by carbonate mud. Many corals and rudists are coated by thick and diverse encrustations
that indicate high nutrient level and/or turbid waters.
The coral-rudist mounds are capped byVaccinites biostromes up to 5 m thick. The establishment of these biostromes may result from unfavourable environmental conditions for
corals, coupled with the potential of the elevator rudists for effective substrate colonization. TheVaccinites biostromes are locally topped by a thin radiolitid biostrome. The biostromes, in turn, are overlain by bioclastic limestones;
these are arranged in stratal packages that were deposited from carbonate sand bodies. Approximately midsection, an interval
of marls with abundantPhelopteria is present. These marls were deposited in a quiet lagoonal area where meadows of sea grass or algae, coupled with an elevated
nutrient level, triggered the mass occurrence ofPhelopteria.
The upper part of the Haidach section consists of stratal packages that each is composed of a rudist biostrome overlain by
bioclastic wackestones to packstones with diverse smaller benthic foraminifera and calcareous green algae. The biostromes
are either built by radiolitids,Vaccinites, andPleurocora, or consist exclusively of radiolitids (mainlyRadiolites). Both the biostromes and the bioclastic limestones were deposited in a low-energy lagoonal environment that was punctuated
by high-energy events.In situ-rudist fabrics typically have a matrix of mudstone to rudistclastic wackestone; other biogens (incl. smaller benthic foraminifera)
are absent or very rare. The matrix of rudist fabrics that indicate episodic destruction by high-energy events contain a fossil
assemblage similar to the vertically associated bioclastic limestones. Substrata colonized by rudists thus were unfavourable
at least for smaller benthic foraminifera.
The described succession was deposited on a gently inclined shelf segment, where coral-rudist mounds and hippuritid biostromes
were separated by a belt of bioclastic sand bodies from a lagoon with radiolitid biostromes. The mounds document that corals
and Late Cretaceous elevator rudists may co-occur in close association. On the scale of the entire succession, however, mainly
as a result of the wide ecologic range of the rudists relative to corals, the coral-dominated mounds and the rudist biostromes
are vertically separated. 相似文献
50.