12.491 is a seminar focusing on problems of current interest in geology and geochemistry. For Fall 2005, the topic is organic geochemistry. Lectures and readings cover recent research in the development and properties of organic matter.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Certain gut microbes and their metabolites contribute to the progression of benign colorectal adenoma (CRA) into colorectal cancer (CRC), but the specific microbes, metabolites, and mechanisms involved are unclear. To learn more, researchers recently analyzed stool samples from patients with CRA or CRC and normal control (NC) subjects. The levels of certain stool metabolites significantly differed among the groups. For example, myristic acid and norvaline became more abundant with progression from health to CRC. The CRC-associated metabolites were largely branched- chain amino acids and aromatic amino acids and were involved in aminoacyl-tRNA biosynthesis pathways. A metabolite “signature” distinguished CRC samples from NC samples and CRC samples from CRA samples and the relationships among CRC-related metabolites and gut bacteria differed in the different sample types..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

Biology is designed for multi-semester biology courses for science majors. It is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand. To meet the needs of today’s instructors and students, some content has been strategically condensed while maintaining the overall scope and coverage of traditional texts for this course. Instructors can customize the book, adapting it to the approach that works best in their classroom. Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand—and apply—key concepts.

By the end of this section, you will be able to:Explain systems biologyDescribe a proteomeDefine protein signature

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Cancer-associated fibroblasts (CAFs) are part of the “soil” in which tumors grow. These cells have diverse origins and can interact with tumor cells in various ways, making it difficult to determine whether they’re friends or foes in cancer treatment. Detecting biomarkers can help address this challenge by allowing researchers to identify different CAF subsets. Several CAF biomarkers are associated with cancer promotion, such as FAP, vimentin, galectin 1, and osteopontin. For example, FAP increases cancer cell invasiveness and leads to immunotherapy resistance. Other CAF biomarkers are associated with cancer inhibition, like meflin, which is linked to a good prognosis in pancreatic and lung cancers. However, some biomarkers can either encourage or suppress cancer depending on the context..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"SARS-CoV-2, the virus that causes COVID-19, continues to course through communities around the world. While researchers have learned enough about the virus to build defenses, much remains unknown about how SARS-CoV-2 interacts with the immune system to cause disease. One promising target researchers are exploring is a process known as “T cell exhaustion.” During infection, disease-fighting T cells are recruited to areas where inflammation is taking place. These cells are virus-specific and represent one of the most critical defenses against SARS-CoV-2. Some patients with COVID-19, however, show significantly reduced T cell counts, impairing their ability to fight the disease. Although it’s unclear how T cell exhaustion occurs, numerous potential biomarkers of this process do exist. Among these is the protein PD-1, which helps T cells identify cells as friend or foe..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"CCL2 is a small cell-signaling protein that recruits immune cells to sites of inflammation. CCR2 is CCL2’s receptor. Together, CCL2 and CCR2 create an inflammatory and immune-suppressive microenvironment, which promotes tumor growth and progression and induces resistance to anticancer drugs. A recent review highlights research on the therapeutic potential of targeting this so-called “CCL2-CCR axis”. Circulating levels of CCL2 are particularly elevated in individuals with obesity. Studies on men with prostate cancer suggest that inhibiting CCL2 signaling can significantly inhibit tumor growth and invasion. More work is needed to differentiate natural CCL2 levels in patients from tumor-derived CCL2 involved in the formation and spread of tumors, which could lead to new ways of attacking cancer and cancer resistance..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Lung cancer is the number one cause of cancer-related death Early detection is key to beating the disease A lung tumour that’s detected early, before it grows too large or spreads to other parts of the body, can be removed by surgeons and essentially cured The problem is that early detection is tricky Most patients don’t develop symptoms until advanced disease has set in, and the most common screening methods can be expensive and impractical Scientists are working on a new blood test that could help The test can spot small bits of DNA floating around in the blood Cancer cells shed this DNA as they grow and multiply Preliminary tests in mice showed the test can detect lung tumours before they become malignant The amount of tumour DNA found in the blood went up as tumours grew, giving scientists an idea of how large a mass had become More work is needed before the test can be used to detect cancer in humans But the research suggests that spotting early-stage lung cancer may one day be.."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Of all the forms of cancer, few are as aggressive as pancreatic adenocarcinoma. The discovery of a tumor in the pancreas is often accompanied by an extremely poor prognosis, even when surgery is an option. But a new technique could help doctors design better treatment strategies for patients with this type of cancer. A recent study carried out by researchers from France and the US highlights a promising new approach to rapidly distinguish pancreatic cancer cells from healthy ones and to predict a patient’s chances of survival after diagnosis. Such predictive power would allow physicians to better assess a patient’s surgical needs and recommend a more personalized treatment plan..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

Students will learn to fabricate, remix, and design detection and monitoring devices for health following the core focus of the Tricorder: a portable, handheld diagnostic device which can brings health solutions to consumers at home or in remote parts of the world. Inspired by the Tricorder X-Prize (with a purse of $10 million), students will aim to create specific component technologies that integrate into a comprehensive Tricorder mechanism capable of reading vital signs and specific disease biomarker detection. Component areas will include optical, electric, biochemical, and molecular diagnostics.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Epigenetic DNA modifications, like methylation, heritably alter gene expression without changing the genetic code. Aberrant epigenetic alterations and dysregulated methylation often drive cancer development. Identifying such alterations could lead to new cancer biomarkers or treatment targets. Colorectal cancer in particular could benefit from epigenetic biomarkers, as it is the third deadliest cancer globally and has limited early detection methods. In a recent study, researchers screened methylation databases of colorectal cancer patients, and they honed in on HAND2, a transcription factor whose promotor region was frequently methylated in these patients. In the lab, experiments demethylating HAND2 reverted its expression in cultured colorectal cancer cells. Demethylation of HAND2 inhibited pro-cancer behavior — proliferation, invasion, and migration — in these cells. HAND2 demethylation also suppressed tumor growth relative to controls in tumor xenograft experiments..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Exosomes are tiny membrane-bound vesicles that could be cutting-edge tools for cancer diagnosis and treatment. Exosomes are released by nearly every cell type to transport biomolecule cargo between cells and can be found in most body fluids. Among exosome cargos, microRNAs have draw significant attention for their role in the development of various diseases. MicroRNAs are small non-coding RNA molecules that can regulate the expression of protein-encoding genes. Exosomal microRNAs have shown promise as diagnostic biomarkers and as therapeutic targets or even therapeutics themselves. Studies have suggested that the microRNAs in cancer cell exosomes resemble the microRNA pool from their parent cancer cell. Exosomal microRNAs may be of particular use for the detection and treatment of hematologic neoplasms, which include cancers like lymphoma and multiple myeloma. However, there are several barriers than need to be addressed before exosomal microRNAs can be used in clinical settings..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Pancreatic cancer continues to have a high mortality rate due to a lack of effective early diagnostic and treatment approaches. However, secreted vesicles called exosomes could hold the key to unlock better strategies. These vesicles contain numerous cargoes, such as lipids, proteins, and nucleic acids and play roles in various processes, including cell–cell communication. Exosomes secreted from pancreatic cancer cells contain signaling molecules that promote cancer progression. These exosome cargoes suppress immunity, facilitate tumor blood vessel formation, and encourage fibrosis, thus creating a more pro-cancer microenvironment. Exosomes can also promote metastasis to distant regions and reprogram normal cells into cancer cells. Despite their negative effects, the molecules in cancer cell–derived exosomes can be used as valuable biomarkers for pancreatic cancer diagnosis and prognosis prediction..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Exosomes are small membrane-bound vesicles that facilitate cell-to-cell communication by transporting biomolecules like proteins, RNA, and lipids. Due to their ubiquity and cargo-carrying abilities, exosomes have many potential uses in clinical medicine. First, they can be found in many biofluids like blood, urine, cerebrospinal fluid, saliva, and milk. This means they’re easy to collect and could be used in diagnostic testing as biomarkers. Beyond that, exosomes can be used to deliver cargo to key cells, either using naturally occurring exosomes or fashioning them into drug delivery vehicles. There are even promising results for exosome-based vaccines, not only for infectious diseases but anti-tumor vaccines as well. While the field has developed rapidly in recent decades, there is much more work to do. Specifically, researchers still need to elucidate the mechanisms of exosome transfer within the body..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"The ligand protein PD-L1 on tumor cells can bind to the receptor protein PD-1 on T cells. This binding negatively regulates T cells to suppress immunity, facilitating large-scale tumor growth. Antibody drugs have been designed to block cell-surface PD-L1/PD-1 binding, but they’re not very effective, possibly because tumor cells can secrete extracellular vesicles (EVs) that express PD-L1. The PD-L1 on EVs can also induce immunosuppression, leading to drug resistance. EV PD-L1 plays tumor-promoting roles in many cancers, such as breast cancer, prostate cancer, and melanoma, and unlike cell-surface PD-L1, which isn’t expressed stably enough to be reliable, EV PD-L1 may be a useful biomarker. Because of its location, EV PD-L1 may also be a good treatment target. For example, drugs preventing EV release have been shown to activate antitumor responses in melanoma cells and to reduce prostate tumor growth and increase anti-PD-L1 efficacy against colon cancer in mice..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Critically ill COVID-19 patients under invasive mechanical ventilation (IMV) are at greatly increased risk of death compared to the general population. While some drivers of COVID-19 disease progression, such as inflammation and hypercoagulability, have been identified, they do not completely explain the mortality of critically ill COVID-19 patients, making a search for overlooked factors necessary. A recent study examined the virome of tracheal aspirates from 25 COVID-19 patients under IMV. These samples were compared to tracheal aspirates from non-COVID patients and nasopharyngeal swabs from individuals with mild COVID-19. Critically ill COVID-19 patients had elevated expression of human endogenous retrovirus K (HERV-K), and elevated HERV-K expression in tracheal aspirate and plasma was associated with early mortality in those same patients. Among deceased patients, HERV-K expression was associated with IL-17-related inflammation, monocyte activation, and increased consumption of clotting factors..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Neutrophil extracellular traps, or NETs, are stringy chromatin networks that are ejected from immune cells to capture and neutralize harmful pathogens. But over-casting NETs can be indicative of disease, including cancer and thrombosis. As a result, NETs have become a promising non-invasive biomarker, and one way to quantify these networks is by detecting a critical component of NETs— histones whose arginine residues have been converted to citrulline, or H3Cit. These assays use antibodies to measure H3Cit in patient plasma, but a recent study shows that existing assays are limited by two important factors: Part of the problem is that available antibodies to H3Cit display low specificity, poor signal-to-noise, and lot variability. The second issue is that these assays are calibrated using enzymatically citrullinated, free histone peptides, which are unstable in human plasma and produce variable performance between batches..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Despite being the standard treatment for lung cancers, immune checkpoint inhibitors (ICIs) are often less effective for patients with EGFR mutations. And these mutations are far from uncommon; 40% of lung adenocarcinoma (LUAD) patients have them, but one protein that might play a role in this process is ARID1A. A recent study examined ARID1A expression in a cohort of LUAD patients with or without EGFR mutations. Overall, low ARID1A expression corresponded to increased immune cell infiltration and longer survival times. The data also suggested that ICIs were more effective for LUAD patients with EGFR mutations if they had low ARID1A expression. Mechanistic experiments in cultured EGFR-mutated LUAD cells suggested that reducing ARID1A expression inhibited autophagy. Autophagy is a normal process in healthy cells, but it helps cancer cells evade the immune system. Specifically, reduced ARID1A expression decreased autophagy by activating the EGFR/PI3K/Akt/mTOR pathway..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Amphibians are one of the most vulnerable animal groups on the planet, with over 40% of their species threatened with extinction. A major driver of that vulnerability is the fungal pathogen _Batrachochytrium dendrobatidis_ (Bd). Bd is linked to the decline of at least 500 amphibian species, the greatest loss in biodiversity due to a pathogen ever recorded. The amphibian skin microbiome community structure has been linked to health outcomes of Bd infection, but the functional importance of the microbiota is not yet fully understood. To close this gap and potentially discover biomarkers or disease control methods, researchers investigated the microbiome of midwife toads. They examined both wild populations with naturally occurring Bd infection and controlled laboratory exposure. Infection with Bd led to changes in the microbial community structure, gene profile, and metabolic function in laboratory and wild toad populations..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.