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Showing posts from January, 2024

Scientists investigate the sensory information hummingbird hawk moths rely on to control their proboscis

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Originally published by University of Konstanz, January 29, 2024   Hummingbird hawk moth (Macroglossum stellatarum) foraging in France (Sorède) Credit: Anna Stöckl Just as when we humans reach for objects, the hummingbird hawk moth uses its visual sense to place its long proboscis precisely on a flower to search for nectar, according to a study by Konstanz biologists. Have you ever seen a hummingbird hawk moth? When people encounter this moth for the first time, they are usually intrigued: Looking like a cross between a butterfly and a bird —hence the name—this animal has the amazing ability to hover like a helicopter for long periods . On closer inspection, another feature of the hummingbird hawk moth quickly catches the eye: the spiraling curled proboscis , which is as long as the entire animal . The moth uses its proboscis to suck nectar by inserting it through a tiny opening into the floral nectaries, seemingly effortlessly and in a matter of seconds . "It's l

New mechanism with potential to boost checkpoint-blocking cancer immunotherapies identified

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O riginally published by University of Aberdeen, on January 15, 2024   Credit: Molecular Therapy (2023). DOI: 10.1016/j.ymthe.2023.11.028 Researchers at the University of Aberdeen working on a partnership study that looks at how the immune system could help improve cancer treatment have found a potential new way to aid and develop better cancer therapies . Together with colleagues at the University of Liverpool and the Center for Cancer Immunology at the University of Southampton , researchers examined the role of CTLA-4 , a cell surface molecule that plays a crucial role in the immune system . Known as a "checkpoint" receptor responsible for maintaining immune balance and tolerance , CTLA-4 works to prevent the immune system becoming too active at the end of a normal immune response. However, it is also subverted by cancer cells to prevent the immune system from attacking them. Researchers developed antibodies targeting CTLA-4 and these have shown promise in tr

Long COVID: Damaged mitochondria in muscles might be linked to some of the symptoms

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Originally published by Caroline Dalton, The Conversation, on January 12, 2024                                           Credit: Pixabay/CC0 Public Domain It's estimated that around 3% of people in the UK experience long COVID — persistent, long-lasting symptoms after a COVID-19 infection. Long COVID encompasses a range of health problems that can begin after even a mild COVID infection. Some of these symptoms include extreme fatigue, shortness of breath, muscle aches and loss of smell . For around 50% of long COVID sufferers , their symptoms also fit criteria for a diagnosis of myalgic encephalomyelitis ( ME ), a neuro-immune disease characterized by depleted energy, muscle weakness and pain, cognitive dysfunction and dysautonomia (which affects blood pressure and heart rate). A cardinal feature of ME is " post-exertional malaise " ( PEM ). This refers to a worsening of symptoms that takes place around 24-48 hours after any form of exertion —whether that

Key moment in the evolution of life on Earth captured in fossils

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Originally published by Curtin University, on January 15, 2024 The Welsh countryside near the Coed Cochion Quarry, where the fossils were found. Credit: Curtin University Curtin-led research has for the first time precisely dated some of the oldest fossils of complex multicellular life in the world , helping to track a pivotal moment in the history of Earth when the seas began teeming with new lifeforms —after 4 billion years of containing only single-celled microbes. The research paper, "U–Pb zircon-rutile dating of the Llangynog Inlier, Wales : Constraints on an Ediacaran shallow 1 marine fossil assemblage from East Avalonia," appears in the Journal of the Geological Society . Lead author Ph.D. student Anthony Clarke, from the Timescales of Mineral Systems Group within Curtin's School of Earth and Planetary Sciences , said to determine the age of the fossils , researchers used volcanic ash layers like bookmarks in the geological sequence. " Located in

When bad cells go good: Harnessing cellular cannibalism for cancer treatment

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O riginally published by University of California - Santa Barbara, on January 7, 2024   A Petri dish transforms into a canvas in Ph.D. student Hadley Hanson's painting of macrophages engulfing cancer cells. Credit: Hadley Hanson Scientists have solved a cellular murder mystery nearly 25 years after the case went cold. Following a trail of evidence from fruit flies to mice to humans revealed that cannibalistic cells likely cause a rare human immunodeficiency . Now the discovery shows promise for enhancing an up-and-coming cancer treatmen t. "This paper takes us from very fundamental cell biology in a fly, to explaining a human disease and harnessing that knowledge for a cancer therapy," said UC Santa Barbara 's Denise Montell. "Each one of those steps feels like a major discovery, but here they are, all in one paper." Researchers in Montell's lab published their findings in the Proceedings of the National Academy of Sciences and are now investi

HKDC1 protein found crucial to maintaining two mitochondria subcellular structures, mitochondria and lysosomes

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Originally published by Osaka University, on January 1, 2024 Overview: Both mitochondrial and lysosomal stress stimulate TFEB nuclear translocation, followed by increased HKDC1 expression. HKDC1 stabilizes PINK1 through interaction with TOM70, thereby facilitating PINK1/Parkin-dependent mitophagy. Additionally, HKDC1 and the VDAC proteins with which it interacts are important for repair of damaged lysosomes and maintaining mitochondria–lysosome contact. HKDC1 prevents DNA damage–induced cellular senescence by maintaining mitochondrial and lysosomal homeostasis. Credit: 2024 Cui et al., HKDC1, a target of TFEB, is essential to maintain both mitochondrial and lysosomal homeostasis, preventing cellular senescence, PNAS . Just as healthy organs are vital to our well-being, healthy organelles are vital to the proper functioning of the cell . These subcellular structures carry out specific jobs within the cell; for example, mitochondria power the cell, and lysosomes keep the cell tidy.

Scientists solve 18-year-old mystery and find the once-elusive source of a critical T cell population

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Originally published by Delthia Ricks , Medical Xpress, on December 28, 2023 P resence of Tcf7+ CD8+ T cells during the primary response to infection. (A) Experimental schematic: Naïve P14 cells (CD45.2) were transferred into congenically distinct B6 mice (CD45.1) that were subsequently infected with LCMV (Arm or WE strain). On the indicated day of infection, P14 cells present in the spleen (unless indicated otherwise) were characterized using flow cytometry. (B) Live cells were gated using FSC-A and SSC.A, followed by doublet discrimination using FSC-H/FSC-A. Next, singlets were gated for alive cells, CD8+ and congenic markers CD45.1 and CD45.2 were used to gate P14 cells. Credit: Science Immunology (2023). DOI: 10.1126/sciimmunol.adh3113 One of the more rigorous debates in immunology has centered on the origin of an enigmatic T cell population that possesses properties imparting memory and stem cell–like qualities, but facts about their genesis were so elusive that debate h