Erfassung der Langzeitergebnisse (10 Jahre) der kombinierten Tele-/HDR-Brachytherapie (Kieler Methode) beim Prostata-Karzinom

Die kombinierte Tele-/High-Dose-Rate-Brachytherapie hat in den letzen Jahren einen festen Stellenwert in der Behandlung des lokalisierten Prostata-Karzinoms eingenommen. Ziel dieser Studie war, die erwünschten und unerwünschten Wirkungen der Radiotherapie bei 244 Patienten, die zwischen 1986 und 1999 in der Klinik für Strahlentherapie des Universitätsklinikums Kiel aufgrund eines primären lokalisierten Prostata-Karzinoms bestrahlt wurden, zu erfassen. Da 1992 das Bestrahlungsprotokoll in Kiel zugunsten einer Reduktion des Bestrahlungsvolumes geändert wurde, stellte der Vergleich der Protokolle (Kiel Protokoll 1: klinisches Zielvolumen der Teletherapie = großes Becken; Kiel Protokoll 2: klinisches Zielvolumen der Teletherapie = kleines Becken) einen weiteren Bestandteil dieser Studie dar. Beide Patientenkollektive wiesen eine Fallzahl von je n = 122 (gesamt n = 244) auf, es wurden sowohl Patienten mit als auch ohne neoadjuvante Hormontherapie in die Studie aufgenommen. Ein Ausschlusskriterium für die Bestrahlung war das Vorliegen von Fernmetastasen zum Zeitpunkt der Diagnosestellung. Die Bestrahlung erfolgte über ca. 5 Wochen mit einer perkutanen Bestrahlung von 5 x 2 Gy pro Woche (gesamt 50 Gy, die lokale Dosis für die Prostata wurde auf 40 Gy limitiert) und zwei Brachytherapiesitzungen in zweiwöchigem Abstand mit je 15 Gy pro Sitzung (gesamt 30 Gy). Die durchschnittliche Nachbeobachtungszeit betrug 93,5 Monate (1,4 – 263 Monate). Es zeigten sich exzellente Langzeitverläufe hinsichtlich Gesamtüberleben, krebsspezifischem Überleben, Lokalrezidvrate, Fernmetastasenrate und tumorfreiem Überleben ohne signifikante Unterschiede zwischen den beiden Protokollen. Nach Auswertung der Ergebnisse in eingeteilte Risikogruppen zeigte sich jedoch ein signifikanter Unterschied zwischen den Protokollen mit schlechterem Abschneiden des Protokoll 2 (reduziertes Volumen) in der High-Risk-Gruppe hinsichtlich der biochemischen Tumorkontrolle (p = 0,02 nach ASTRO; p = 0,03 nach Phoenix). Die Auswertung des zeitlichen Auftretens von Lokalrezidiven zeigte eine Zweigipfeligkeit mit erstem größeren Gipfel innerhalb der ersten fünf Jahre nach Therapie und einem zweiten Gipfel nach ca. 160 Monaten. Dieses Phänomen unterstreicht nachhaltig die Notwendigkeit einer sorgfältigen Nachsorge der Patienten über Jahrzehnte hinweg. Eine deskriptive Darstellung der Spätnebenwirkungen von Grad 2 und Grad 3 (Grad 1 wurde nicht berücksichtigt, Grad 4 ist bei keinem Patienten aufgetreten) nach einem nach der RTOG/EORTC-Klassifikation modifizierten Dokumentationsbogen zeigte eine tendenziell bessere Verträglichkeit der Strahlentherapie bei der Behandlung nach dem Kiel Protokoll 2. Insgesamt kam es bei 35 Patienten (14,3 %) zu Spätnebenwirkungen, was für eine insgesamt sehr gute Verträglichkeit der kombinierten Tele-/High-Dose-Rate-Brachytherapie spricht. Hinsichtlich der guten Langzeitergebnisse, die diese Studie hervorbringt, lässt sich festhalten, dass die kombinierte Tele-/High-Dose-Rate-Brachytherapie zu Recht einen festen Platz in der Therapie des lokalisierten Prostata-Karzinoms, insbesondere des High-Risk-Karzinoms, eingenommen hat. Die Ergebnisse dieser Studie zeigen, dass die Reduktion des Bestrahlungsvolumes auf das kleine Becken gleichwertige Ergebnisse gegenüber der Bestrahlung des vollen Beckens bei geringerer Toxizität erbringt und somit zukünftig weiterhin für Non-High-Risk- Karzinome zu empfehlen ist. Aufgrund des signifikant schlechteren Outcomes hinsichtlich der biochemischen Tumorkontrolle sollte jedoch bei High-Risk- Karzinomen empfohlen werden, eher wieder das große Becken als klinisches Zielvolumen der Teletherapie einzuführen und dabei moderne, hochkomplexe Techniken mit reduzierter Toxizität anzuwenden

Molecular evolution of GII-4 Norovirus strains.

BACKGROUND: Human Noroviruses (NoV) are the major cause of acute nonbacterial gastroenteritis and the leading cause of outbreaks of gastroenteritis worldwide. Genotype II-4 (GII-4) NoV has been shown to spread rapidly and is the most commonly detected strain worldwide, particularly in association with outbreaks. Previously, we have shown that circulating GII-4 NoV strains exist as populations of selectively neutral variants, and that the emergence of epidemic GII-4 NoV strains correlated with mutations in at least two key sites (Sites A and B) within the P2 domain of the surface exposed major capsid protein (VP1). METHODOLOGY: We developed a rapid pyrosequencing method for screening of the two Sites A and B and a homology based modelling system was used to predict the effects of amino acid substitutions at these sites on the antigenic properties of the virus (defined as surface motif types). PRINCIPLE FINDING/CONCLUSION: Here, we describe the characterisation of amino acid diversity at Sites A and B for 1062 GII-4 NoV strains from clinical specimen associated with outbreak of gastroenteritis (2000-2011) and 250 GII-4 NoV sequences from Genbank. Our data identified a high diversity of different Site A and B site combinations at amino acid level and amino acid diversity was higher at Site B than Site A. Site A motifs could be grouped into 3 clusters based on similar surface motif types. We predict that Site A is a major epitope on the virus surface, responsible for defining the antigenic profile, and a more subtle role for Site B, maintaining minor antigenic variation within the virus population

Molecular and proteomic analyses highlight the importance of ubiquitination for the stress resistance, metabolic adaptation, morphogenetic regulation and virulence of Candida albicans

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Hsp21potentiates antifungal drug tolerance in Candida albicans

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Common and divergent features in transcriptional control of the homologous small RNAs GlmY and GlmZ in Enterobacteriaceae

Small RNAs GlmY and GlmZ compose a cascade that feedback-regulates synthesis of enzyme GlmS in Enterobacteriaceae. Here, we analyzed the transcriptional regulation of glmY/glmZ from Yersinia pseudotuberculosis, Salmonella typhimurium and Escherichia coli, as representatives for other enterobacterial species, which exhibit similar promoter architectures. The GlmY and GlmZ sRNAs of Y. pseudotuberculosis are transcribed from σ54-promoters that require activation by the response regulator GlrR through binding to three conserved sites located upstream of the promoters. This also applies to glmY/glmZ of S. typhimurium and glmY of E. coli, but as a difference additional σ70-promoters overlap the σ54-promoters and initiate transcription at the same site. In contrast, E. coli glmZ is transcribed from a single σ70-promoter. Thus, transcription of glmY and glmZ is controlled by σ54 and the two-component system GlrR/GlrK (QseF/QseE) in Y. pseudotuberculosis and presumably in many other Enterobacteria. However, in a subset of species such as E. coli this relationship is partially lost in favor of σ70-dependent transcription. In addition, we show that activity of the σ54-promoter of E. coli glmY requires binding of the integration host factor to sites upstream of the promoter. Finally, evidence is provided that phosphorylation of GlrR increases its activity and thereby sRNA expression

Small but crucial : the novel small heat shock protein Hsp21 mediates stress adaptation and virulence in Candida albicans

Peer reviewedPublisher PD

Calcium homeostasis is required for contact-dependent helical and sinusoidal tip growth in Candida albicans hyphae

Hyphae of the dimorphic fungus, Candida albicans, exhibit directional tip responses when grown in contact with surfaces. On hard surfaces or in liquid media, the trajectory of hyphal growth is typically linear, with tip re-orientation events limited to encounters with topographical features (thigmotropism). In contrast, when grown on semisolid surfaces, the tips of C. albicans hyphae grow in an oscillatory manner to form regular two-dimensional sinusoidal curves and three-dimensional helices. We show that, like thigmotropism, initiation of directional tip oscillation in C. albicans hyphae is severely attenuated when Ca2+ homeostasis is perturbed. Chelation of extracellular Ca2+ or deletion of the Ca2+ transporters that modulate cytosolic [Ca2+] (Mid1, Cch1 or Pmr1) did not affect hyphal length but curve formation was severely reduced in mid1Δ and cch1Δ and abolished in pmr1Δ. Sinusoidal hypha morphology was altered in the mid1Δ, chs3Δ and heterozygous pmr1Δ/PMR1 strains. Treatments that affect cell wall integrity, changes in surface mannosylation or the provision of additional carbon sources had significant but less pronounced effects on oscillatory growth. The induction of two- and three-dimensional sinusoidal growth in wild-type C. albicans hyphae is therefore the consequence of mechanisms that involve Ca2+ influx and signalling rather than gross changes in the cell wall architecture

Evaluation of the Role of Candida albicans Agglutinin-Like Sequence (Als) Proteins in Human Oral Epithelial Cell Interactions

The fungus C. albicans uses adhesins to interact with human epithelial surfaces in the processes of colonization and pathogenesis. The C. albicans ALS (agglutinin-like sequence) gene family encodes eight large cell-surface glycoproteins (Als1-Als7 and Als9) that have adhesive function. This study utilized C. albicans Δals mutant strains to investigate the role of the Als family in oral epithelial cell adhesion and damage, cytokine induction and activation of a MAPK-based (MKP1/c-Fos) signaling pathway that discriminates between yeast and hyphae. Of the eight Δals mutants tested, only the Δals3 strain showed significant reductions in oral epithelial cell adhesion and damage, and cytokine production. High fungal:epithelial cell multiplicities of infection were able to rescue the cell damage and cytokine production phenotypes, demonstrating the importance of fungal burden in mucosal infections. Despite its adhesion, damage and cytokine induction phenotypes, the Δals3 strain induced MKP1 phosphorylation and c-Fos production to a similar extent as control cells. Our data demonstrate that Als3 is involved directly in epithelial adhesion but indirectly in cell damage and cytokine induction, and is not the factor targeted by oral epithelial cells to discriminate between the yeast and hyphal form of C. albicans

A European multicentre evaluation of detection and typing methods for human enteroviruses and parechoviruses using RNA transcripts

Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in-house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV species (EV-A71, echovirus 30, coxsackie A virus 21, and EV-D68), HPeV3, and specificity controls. Reported results from 48 in-house and 15 commercial assays showed 98% detection frequencies of high copy (1000 RNA copies/5 mu L) transcripts. In-house assays showed significantly greater detection frequencies of the low copy (10 copies/5 mu L) EV and HPeV transcripts (81% and 86%, respectively) compared with commercial assays (56%, 50%; P = 7 x 10(-5)). EV-specific PCRs showed low cross-reactivity with human rhinovirus C (3 of 42 tests) and infrequent positivity in the negative control (2 of 63 tests). Most or all high copy EV and HPeV controls were successfully typed (88%, 100%) by reference laboratories, but showed reduced effectiveness for low copy controls (41%, 67%). Stabilized RNA transcripts provide an effective, logistically simple and inexpensive reagent for evaluation of diagnostic assay performance. The study provides reassurance of the performance of the many in-house assay formats used across Europe. However, it identified often substantially reduced sensitivities of commercial assays often used as point-of-care tests.Peer reviewe