Corona-Mutation: Ärztekammer warnt vor Reisen in Delta-Gebiete

Mitten in der Urlaubszeit breitet sich die Delta-Variante des Coronavirus aus. Laut Ärztekammer sollte dies bei der Reiseplanung beachtet werden.

Quelle: SPIEGEL ONLINE

Coronavirus: Delta-Mutante setzt sich laut Intensivmedizinern durch

In den kommenden Wochen werde sich die gefährlichere Mutation B.1.617.2 in Deutschland weiter ausbreiten, sagt Intensivmediziner Gernot Marx. Eine vierte Welle sei möglich.

Quelle: SPIEGEL ONLINE

New findings offer improved therapy of early-stage, BRCA mutation-associated breast cancer

A new treatment has potential to improve the outcomes for patients with hereditary BRCA mutations and high-risk, early-stage breast cancer. These results represent the first time a PARP inhibitor has been shown to significantly reduce the risk of breast cancer returning in high-risk patients following completion of standard chemotherapy, surgery and radiation therapy.

Quelle: Sciencedaily

Wie sich „gelähmte” Immunzellen gegen Hirntumoren reaktivieren lassen

Hirntumorzellen, die eine bestimmte, häufige Mutation tragen, programmieren einwandernde Immunzellen um und lähmen dadurch im Gehirn die körpereigene Abwehr gegen den Tumor. Das entdeckten Wissenschaftler aus Heidelberg, Mannheim und Freiburg und fanden gleichzeitig einen Weg, wie sie das lahmgelegte Immunsystem wieder gegen den Tumor aktivieren können. Diese Ergebnisse bestätigen, dass therapeutische Impfungen oder Immuntherapien gegen Hirntumoren besser wirken, wenn gleichzeitig das unterdrückte Immunsystem mit Wirkstoffen unterstützt wird.

Quelle: IDW Informationsdienst Wissenschaft

Cholesterol Levels Sustainably Lowered Using Base Editing

Base editing is a novel gene editing approach that can precisely change individual building blocks in a DNA sequence. By installing such a point mutation in a specific gene, an international research team led by the University of Zurich has succeeded in sustainably lowering high LDL cholesterol levels in the blood of mice and macaques. This opens up the possibility of curing patients with inherited metabolic liver diseases.

Quelle: IDW Informationsdienst Wissenschaft

Corona-News am Mittwoch: Indische Coronavariante in mehr als 44 Ländern erfasst

Die zuerst in Indien entdeckte Mutation hat sich nach WHO-Angaben rasch verbreitet. Wie sie auf Impfstoffe reagiert, ist noch unklar. Und: Trotz Tourismus infizieren sich in Schleswig-Holstein nur wenige Menschen. Der Überblick.

Quelle: SPIEGEL ONLINE

Hopkins-led research team takes gene mutation detection in blood to the next level

Researchers have developed a new technology to overcome the inefficiencies and high error rates common among next-generation sequencing techniques that have previously limited their clinical application.

Quelle: Sciencedaily

Corona-Mutante in Indien: Christian Drosten beruhigt hinsichtlich Gefahr von Mutation B.1.617

Das Gesundheitssystem Indiens steht angesichts der hohen Corona-Infektionszahlen vor dem Zusammenbruch. Der Virologe Christian Drosten hält nicht allein die Mutation B.1.617 für die drastische Lage verantwortlich.

Quelle: SPIEGEL ONLINE

Corona-Mutation aus Indien erreicht Europa – nach Varianten aus Südafrika und Brasilien

Die Infektionszahlen in indischen Megastädten explodieren. Forscher befürchten, dass dies an einer neuen Corona-Mutation liegt, die nun auch Europa erreicht hat. Wie gefährlich ist B.1.617?

Quelle: SPIEGEL ONLINE

Coronavirus-Mutation: B.1.1.7 wohl doch nicht tödlicher, aber höhere Viruslast

Zwei neue Studien weisen darauf hin, dass die in Großbritannien entdeckte Virusvariante den R-Wert erhöht. Damit hat sie erheblichen Einfluss auf das Infektionsgeschehen.

Quelle: SPIEGEL ONLINE

Brasilien: Was macht die Coronavirus-Mutation P.1 so gefährlich?

Die zweite Welle traf Manaus in Brasilien mit voller Wucht, das Gesundheitssystem brach zusammen. Eine Ursache: eine neue Virusmutante, die sich nun weltweit verbreitet. Was ist über P.1 bekannt?

Quelle: SPIEGEL ONLINE

Retracing the history of the mutation that gave rise to cancer decades later

Researchers reconstructed the evolutionary history of cancer cells in two patients, tracing the timeline of the mutation that causes the disease to a cell of origin. In a 63-year-old patient, it occurred at around age 19; in a 34-year-old patient, at around age 9.

Quelle: Sciencedaily

Cancer ‚guardian‘ breaks bad with one switch

A mutation that replaces a single amino acid in a potent tumor-suppressing protein makes it prone to nucleating amyloid fibrils implicated in many cancers as well as neurological diseases.

Quelle: Sciencedaily

A global assessment of cancer genomic alterations in epigenetic mechanisms

Muhammad A Shah, Emily L Denton, Cheryl H Arrowsmith, Mathieu Lupien and Matthieu Schapira

Abstract

Background

The notion that epigenetic mechanisms may be central to cancer initiation and progression is supported by recent next-generation sequencing efforts revealing that genes involved in chromatin-mediated signaling are recurrently mutated in cancer patients.

Results

Here, we analyze mutational and transcriptional profiles from TCGA and the ICGC across a collection 441 chromatin factors and histones. Chromatin factors essential for rapid replication are frequently overexpressed, and those that maintain genome stability frequently mutated. We identify novel mutation hotspots such as K36M in histone H3.1, and uncover a general trend in which transcriptional profiles and somatic mutations in tumor samples favor increased transcriptionally repressive histone methylation, and defective chromatin remodeling.

Conclusions

This unbiased approach confirms previously published data, uncovers novel cancer-associated aberrations targeting epigenetic mechanisms, and justifies continued monitoring of chromatin-related alterations as a class, as more cancer types and distinct cancer stages are represented in cancer genomics data repositories.

Continue reading „A global assessment of cancer genomic alterations in epigenetic mechanisms“

A Mitochondrial Paradigm of Metabolic and Degenerative Diseases, Aging, and Cancer: A Dawn for Evolutionary Medicine

Progressive increase in mtDNA 3243A>G heteroplasmy causes abrupt transcriptional reprogramming

Wallace hypothesized mitochondrial dysfunction as a central role in a wide range of age-related disorders and various forms of cancer. Steadily rising increases in mitochondrial DNA mutations cause abrupt shifts in diseases. Discrete changes in nuclear gene expression in response to small increases in DNA mutant level are analogous to the phase shifts that is well known in physics: As heat is added, the ice abruptly turns to water or with more heat abruptly to steam. Therefore, a quantitative change that is an increasing proportion of mitochondrial DNA mutation results in a qualitative change  which coordinate changes in nuclear gene expression together with discrete changes in clinical symptoms.

 Wallace DC (2005) A Mitochondrial Paradigm of Metabolic and Degenerative Diseases, Aging, and Cancer: A Dawn for Evolutionary Medicine. Annu Rev Genet. 2005 ; 39: 359. doi:10.1146/annurev.genet.39.110304.095751

Picard M et. Al (2014) Progressive increase in mtDNA 3243A>G heteroplasmy causes abrupt transcriptional reprogramming. PNAS E4033–E4042, doi: 10.1073/pnas.1414028111

Variation in cancer risk among tissues can be explained by the number of stem cell divisions

Tomasetti and Vogelstein show that the lifetime risk of cancers of many different types is strongly correlated with the total number of divisions of the normal self-renewing cells maintaining that tissue’s homeostasis. These results suggest that only a third of the variation in cancer risk among tissues is attributable to environmental factors or inherited predispositions. The majority is due to bad luck, that is, random mutations arising during DNA replication in normal, noncancerous stem cells.

Tomasetti C, Vogelstein B (2015): Variation in cancer risk among tissues can be explained by the number of stem cell divisions. Science 2 January 2015: Vol. 347 no. 6217 pp. 78-81 DOI: 10.1126/science.1260825