Joseph P.

Open AI is hiring a Killswitch Engineer - do you know anyone that has the required qualifications ?

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Joseph P.

Sorry I’m not trying to spam just learning how to use mastodon 😅🙏🏻 @TheRedElm

TINTIN AND THE COOKING CAT
"I'm famished," said Tintin. He had walked all day, and his stomach was grumbling. "Let's find a restaurant, Snowy."
Snowy barked in agreement, and they entered the nearest café.
The waiter approached. "What can I get you?" he asked.
"I'll have the spaghetti," said Tintin.
The waiter nodded and disappeared.
A few minutes later, the waiter returned with a plate of spaghetti. Tintin took a bite and suddenly stopped.
"What's wrong?" Snowy asked.
Tintin held up a hair. "This is definitely not part of the recipe!"
Snowy sniffed the spaghetti. "It smells delicious," he said.
Tintin looked at him suspiciously. "Have you been cooking?"
Snowy's ears drooped. "Well, yes," he admitted. "I know how to make spaghetti. I used to watch the chef at Marlinspike Hall."
Tintin smiled. "It's really good," he said.
Snowy's eyes lit up. "Do you really mean it?"
"Yes," said Tintin. "But there's still one problem—we have to get rid of the hair."
They laughed, and Snowy promised to be more careful with the cooking in the future.
QT: qoto.org/@tonic/10984643664104

Joseph P.  
TINTIN AND THE COOKING CAT "I'm famished," said Tintin. He had walked all day, and his stomach was grumbling. "Let's find a restaurant, Snowy." Sno...
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Joseph P.

Do you like these ?

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Joseph P.

TEAM ONE FIST :
Operation Turn Ruzzia Off successfully demolished 316 Metro and Edge routers across Orcland, and disabled another 944! 🔥

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Joseph P.

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Joseph P.

I just used @gpt3 inside google sheets on unstructured data , and got fairly good results in a matter of seconds for a job that would take me more than one afternoon … let me know what you think how cool is this 😅😍

1
Joseph P.

@explainpaper

Tumoral Immune Cell Exploitation in Colorectal Cancer Metastases Can Be Targeted Effectively by Anti-CCR5 Therapy in Cancer Patients

Niels Halama, Inka Zoernig, Anna Berthel, Christoph Kahlert, Fee Klupp, Meggy Suarez-Carmona,Thomas Suetterlin, Karsten Brand, Juergen Krauss, Felix Lasitschka, Tina Lerchl, Claudia Luckner-Minden, Alexis Ulrich, Moritz Koch, Juergen Weitz, Martin Schneider, Markus W. Buechler, Laurence Zitvogel,
Thomas Herrmann, Axel Benner, Christina Kunz, Stephan Luecke, Christoph Springfeld, Niels Grabe, Christine S. Falk, and Dirk Jaeger

Targeting Tumor-Promoting Microenvironment Through CCR5 Blockade in Metastases

progression is a process in which cancer cells and cells interact with each other in a way that can lead to the growth and spread of cancer. In cancer, when the cancer has spread to other parts of the body, it is called and it is very difficult to treat. Treatments such as PD-1/PD-L1 blockade and modulation have been successful in modifying the interactions between the immune system and cancer, leading to the rejection or suppression of progression. Cancer cells can also alter the immune microenvironment, leading to and evasion. In this research paper, the authors studied the microenvironment in metastases and identified a network of cells and immune cells that exploit the CCL5-CCR5 axis. They then investigated and characterized the effects of blocking the CCL5-CCR5 axis.

the microenvironment of metastases of cancer ().

the environment induces migration of T lymphocytes, which produce a called CCL5. This CCL5 then supports tumor growth and spread by influencing macrophages and cells. The environment is immunosuppressive and the tumor cells are exploiting the host's cells to their advantage. In other words, the tumor cells are using the host's immune cells to help them grow and spread.

the effects of CCR5 blockade on the level.

Tumor death and a specific pattern of and modulation are observed in the and in biopsies from a . Macrophages are the key for these anti-tumoral effects, as they produce IFNs and reactive oxygen species which cause tumor cell death. blockade induces a phenotypic shift in the macrophages, which is referred to as a switch from an M2 to an M1 phenotype. This repolarization also reduces levels of CD163+ cells, reshaping the cell composition in the microenvironment. The influx of new effector cells due to CCR5 inhibition can shift the effects of CCL5 towards beneficial effects, such as reduction of , , and resistance.

The microenvironment of the invasive margin of metastases.

There was no relevant Th1, Th2, or Th17 signature present in any of the samples. However, the authors did find that and -related cytokines were significantly increased at the invasive margin. Chemokines are molecules that help to attract cells to the area, and macrophage-related cytokines are molecules that help to regulate the activity of , which are a type of immune cell. 98% of the CD3+ s in the resection specimens were positive for PD-1, which is a molecule that helps to regulate the activity of the immune system.

is a protein produced by T cells, which are a type of white blood cell. is a receptor found on metastatic tumor cells, which are cancer cells that have spread from the primary to other parts of the body. In this research paper, it was found that CCL5 has tumor-promoting effects on cells and tumor-associated s. This means that CCL5 has multiple effects on both the cancer cells and the macrophages, which are a type of white , that are associated with the . CCL5 was produced mainly by T cells located at the invasive margin and stroma of metastases, and that CCR5 was dominantly expressed by metastatic tumor cells. CCL5 also had effects on tumor , invasive tumor , and increased production of matrix es by tumor-associated macrophages. Finally, they found that CCR5 inhibition had an effect on key molecules of to transition ( ).

The researchers wanted to test the effects of blockade, which is a way of blocking the CCR5 receptor on cells, using a drug called maraviroc. They used human s, which are samples of from advanced patients with metastases. Maraviroc led to morphologically overt tumor in the , which means that the tumor cells died and changed in appearance. The researchers then tested the hypothesis that s, (type of white blood cell), were required for the tumor cell death-inducing effects of CCR5 blockade. They used clodronate s to deplete CD163+ TAMs, ( s associated with tumors) and found that combining clodronate with CCR5 inhibition abrogated the immediate tumor cell death-inducing effects of inhibition. This confirmed the role of macrophages in this process. IFN-g induced stromal CD163+ death and led to a reconfiguration of the cell compartment. Inhibition of macrophage-derived reactive oxygen species could partially block the anti-tumoral effects of CCR5 inhibition. Finally, they tested the effects of CCL5/CCR5 inhibition and found that both a CCL5 neutralizing antibody and a CCR5 blocking had similar functional effects to maraviroc.

A (MARACON) was conducted to test the effects of a drug called maraviroc on patients with advanced-stage colorectal . The involved taking biopsies of the patients before and after treatment with maraviroc, and the results showed that the drug had beneficial effects on the tumor-promoting and led to objective clinical responses. These responses included induction of central , reduction of tumor cell death, and reduction of key s and growth factors that promote tumor growth. The drug was also found to be very well tolerated, with mild elevation of enzymes being the most common side effect. Finally, the trial showed that partial responses were achieved in patients with previously refractory disease.

CCR5 blockade, is a type of used to treat .

The MARACON clinical trial, showed that CCR5 blockade had a positive effect on the tumor microenvironment and led to a higher response rate in subsequent chemotherapies. The authors suggest that this effect is not limited to the metastases, but is a systemic feature. They also suggest that the local presence of multiple layers of subversion in cancers depends on the individual tissue, , tumor type, and the difference between primary and metastatic lesion. The authors also found that the results of the were in line with the results of a fully human organotypic tumor , which is a simple model with a straightforward approach. The authors also note that the survival data from the trial is not conclusive due to the limited number of patients, but that the objective treatment responses are very encouraging. They suggest that CCR5 blockade may be a promising approach and needs to be evaluated further scientifically and clinically.

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Joseph P.

Cynically Holding Hostages is Part and Parcel of Russian Colonial Ethos

The history of holding foreign s dates back to the 16th century during Ivan the Terrible's reign. In 1575, Ivan the Terrible captured Swedish military commander, Jacob De La Gardie, and held him hostage for two months in order to gain power over Sweden. In 1602, Tsar Boris Godunov captured King Christian IV of Denmark in what became known as the “Long Steppe Hostage Crisis.” The Tsar demanded a large ransom, but Christian was released after two months due to the intervention of the ambassador from England.

In the 19th century, Russia held several high profile foreign hostages in a bid to influence foreign policy. In 1809, Alexander I captured Archduke Ferdinand (later Emperor of Austria) on his way to Paris, in an attempt to prevent him from marrying Napoleon's step-daughter. The Tsar held the Archduke as a hostage until he agreed to send Russian troops to fight in the Russian-Turkish of 1828—1829.

In recent years, Russia has been accused of holding foreign hostages and prisoners of war to gain political and diplomatic leverage. In 2016 , Russia held pilot Nadiya Savchenko as a hostage during the ongoing conflict in eastern Ukraine. In 2017, the Ukrainian government accused Russia of holding other Ukrainian soldiers hostage. In April 2018, the Russian government was accused of using Foreign hostages as bargaining chips in negotiations with other countries. In May 2018, a mass evacuation of Russian soldiers from Aleppo, Syria, was reportedly done in exchange for the release of two prisoners held in Russia. Russia has also been accused of using foreign hostages as leverage in negotiations with other countries. In December 2019, two citizens were detained in Moscow on charges of espionage, and were held as hostages in what was seen as a diplomatic move to pressure into supporting 's position in the conflict.

There are still several foreign hostages being held in Russia, for example - Naama Issachar, who has been held in a Russian jail since October 2019 after attempting to smuggle a small amount of marijuana into the country. Another high profile hostage currently held in Russia is former marine Paul Whelan, who has been accused of espionage and held in a Moscow prison since 2018. Another high profile hostage held by Russia is Kahlid El-Masri, a - man who has been held in a prison camp in the Republic since 2011. Turkish-German journalist Deniz Yucel, has been held in pre-trial detention since February 2017 on suspicion of and .

Sports figures held hostage by russia include athletes, who have been detained in connection with doping violations and held in Russia despite calls from international organizations, including the International Olympic Committee, to free them. For example in 2016, Russian athletes were held in pre-trial detention in connection with an alleged system of state-sponsored and were not allowed to leave the country. Another hostage in russia is American businessman Michael , who has been held in a Moscow prison since February 2019 on charges of embezzlement. Calvey's case is seen as another example of Russia using foreign hostages as diplomatic leverage. German footballer Mesut , was held in a Moscow for two weeks in 2018 after being accused of engaging in public criticism of the Russian government. player Dennis , made several trips to North Korea in 2013, 2014 and 2017 and was detained in Russia during those trips. American Olympian and four-time world champion figure skater, Rudy Galindo, was detained by Russian authorities in January 2018, and forced to stay in the country until February of that year. ski jumper Kamil Stoch, was held in Russia for a week in February 2017 after being accused of doping violations. American ice dancer Maia , was held in a Moscow airport for over 24 hours in 2018. The U.S. State Department was eventually able to secure her release. Ice hockey player Alexander , who was held in Russia for two months in 2020 after being accused of participating in a banned protest in Moscow. Ovechkin was eventually released, and the charges against him were dropped. American cross-country skier Jessica Diggins, was detained in Russia in January 2020 while traveling to the Sochi Olympics. Diggins was eventually released after the U.S. embassy provided her with a travel visa. American snowboarder Lindsey Jacobellis, was detained in for over a month in 2019. Jacobellis was eventually released after the U.S. was able to secure her release. American Tim Johnson, was detained in 2016 in a case of mistaken identity. Johnson was eventually released after the U.S. embassy helped to secure his release. American mountain Steve Smith, was detained in Russia in 2019 after being accused of participating in an illegal demonstration. Smith was eventually released after the U.S. embassy provided him with a travel visa. American figure skater , was detained in Moscow in 2016 after being accused of participating in an unauthorized demonstration. Wagner was eventually released after the U.S. embassy provided her with a travel visa. Wagner later wrote about her experience in her book, Unbalanced: The Fight for My Life. American figure skater , was detained in a Moscow airport for nine hours in 2019. Rippon was eventually allowed to leave the country after the U.S. embassy intervened. American bobsledder Bree Schaaf, was detained in Moscow in 2017 after being accused of participating in an unauthorized demonstration. Schaaf was eventually allowed to leave the country after the U.S. embassy intervened.

Russian authorities have also been accused of holding foreign religious figures hostage for political gain. In 2018, Russian authorities detained American Andrew on charges of espionage and terrorism and held him as a hostage for two years until he was eventually released in October 2020. In recent years, Russia has also been accused of holding foreign hostages in exchange for political and diplomatic gains. In March 2020, the US Department of State accused Russia of holding two American citizens hostage in an attempt to gain concessions in #

Syria. There have also been reports of Russian authorities detaining foreign citizens in exchange for political and diplomatic gains.

Overall, the history of Russia holding foreign hostages stretches back centuries and continues to this day. The Russian government has used foreign hostages as bargaining chips in negotiations with other countries and as a means of diplomatic leverage. Moreover, sports figures and other people have been held by Russia for political or criminal purposes. though the exact number of foreign hostages held by Russia is unknown, the practice of holding foreign hostages has been a common feature of Russian foreign policy for centuries.

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Joseph P.

@explainpaper

The Uprising of Mitochondrial DNA Biomarker in Cancer

Authors : Siti Zulaikha Nashwa Mohd Khair, Siti Muslihah Abd Radzak and Abdul Aziz Mohamed Yusoff

@bio

Advances in predictive @diagnostic and @precisionmedicine , can lead to powerful discoveries and treatments for patients. @cancer cells acquire functional capabilities to survive, proliferate, and circulate due to an enabling characteristic called genomic instability. Genomic maintenance systems have the ability to spot and repair any @dna defects, while cancer cells increase the rates of @mutation that orchestrate @Tumorigenesis . @chromosomalinstability ( @cin ) is one of the most frequent changes observed in cancer cells, which often results from aberrations in chromosome structures and numbers. The second section of the paper focuses on @biomarkers , which are substances, structures, or processes that can influence or predict the incidence and outcome of a @disease . There are three classifications of biomarkers: exposure, effect, and susceptibility. Biomarkers of exposure measure exogenous chemicals or their metabolites within an organism, while biomarkers of effect measure alterations of endogenous factors caused by exposure to an exogenous agent. Biomarkers of susceptibility measure genetic @polymorphism predisposition of individuals and their external multifactorial influencers. Surrogate endpoints are often used to substitute @clinical endpoints, and biomarkers can be used as a screening tool for an early indicator of @malignancy -risk development. They can also be used as diagnostic aids and @prognostic biomarkers, as well as predictive biomarkers to identify the sensitivity and/or resistance of cancer patients towards specific agents or @medical product exposure.

The communication between the @nucleus and @mitochondria of a cell is known as @intergenomic @crosstalk and it is bidirectional, meaning it can go both ways. It is important for regulating @energy @metabolism and @tumor suppression. The communication is achieved by pathways such as anterograde @signaling and retrograde signaling. Anterograde signaling is when the nucleus controls gene transcription and cytoplasmic @mrna translation in response to external signals. Retrograde signaling is when @mitochondrialdysfunction or loss of mitochondrial @membrane potential triggers communication with the nuclear genetic compartment. This communication is important for @homeostasis adaptation and can detect any nuclear damage or nuclear stress.

@mitochondria are @organelle s found in cells that are responsible for producing energy. They are believed to have originated from a @singlecell -ed organism and are made up of two membranes. They contain their own @genetic material, called @mtdna, which is made up of 16569 @nucleotide base pairs. @mtdna mutations can lead to mitochondrial dysfunction, which can cause #@onco -genic events, such as @tumor @cell reprogramming and metabolic shifts. @mitoepigenetics is the study of how @epigenetics mechanisms regulate @mtdna transcription and replication, and it is believed to be involved in @cancer progression.

The interconnection between @carcinogenesis (the development of @cancer) and @mitochondria (the energy-producing organelles in cells) was first proposed in 1973. Since then, there have been many studies done on this topic, using @dna scanning technologies to detect mutations and deletions. Mitochondrial DNA ( @mtdna ) is beneficial for @carcinogenic studies because it consists of 37 @gene s with no introns, meaning most mutations will occur in coding regions. Additionally, @mtdna has a small size, is easy to extract, has no @genetic rearrangements, and has fast mutation rates, which makes it useful for molecular research. It also has a high copy number, meaning only minimal @tissue samples are needed for analysis. Large-scale deletions are commonly known to be responsible for mitochondrial diseases, and are thought to be the cause of various diseases and cancers.

Two types of @mtdna deletions, 3.4 kb and 4977 bp are associated with various types of cancer. The 3.4 kb deletion was patented by Parr et al. [97] and is used to detect @cancer in individuals. It is also used to determine different @prostate @tissue types, either benign, malignant, or proximal to malignant [100]. The 4977 bp deletion is primarily associated with @aging and is a common deletion with missing @mtdna nucleotide sequences starting at 8470 to 13447 np [106]. It has been studied in various types of cancer, such as @Breastcancer, @colorectal, @gastric, @hepatocellular, and @Brain tumors, and is thought to be associated with external environmental factors, @genetic predisposition, and ethnicity.

The text is discussing different types of deletions in @mtdna (mitochondrial @dna) that are associated with @cancer. The 5.1.3 section is talking about the 3895 bp deletion, which was first observed in 1991 in two patients with progressive external @Ophthalmoplegia . It was then found to be 10 times less frequent than the 4977 bp deletion. A study involving 104 age-matched subjects showed that the 3895 bp deletion was more frequent in those with usually sun-exposed @skin and non @melanoma @skincancer . The 4576 bp deletion was then discussed, which was found to be an indicator for @Breastcancer in a study involving 39 breast cancer patients. The 4576 bp deletion was not found in 23 normal patients without breast cancer. The @mtdna copy number is the amount of @mtdna in each @cell . It is suggested that @mtdna copy number changes may lead to mitochondrial instability and regulate energy @metabolism , which can initiate @Tumorigenesis . Studies have also shown that @mtdna copy number changes can be used as a predictive @biomarker for @Chemotherapy response.

@cellfree mtDNA (cf-mtDNA) is a type of mitochondrial DNA that is released into the @Blood circulation due to disruption of the normal mitochondrial life cycle. It is believed to activate the Toll-like receptor 9 (TLR9) pathway, which can cause @Inflammation and potentially lead to @cancer . It has been used to diagnose cancer and @sepsis , and as a @biomarker for @metabolicsyndrome and predicting the risk of future @diabetes . It is also being studied as a @noninvasive liquid @Biopsy for @cancer, as higher levels of cf-mtDNA have been found in cancer patients compared to healthy controls. @research is being conducted to find the potential link between cf-mtDNA and various cancers, as it is a preferable biomarker due to its higher @mtdna copy number, simpler structure, and shorter length.

Mitochondrial Microsatellite Instability (@mtmsi) is a type of genetic mutation that occurs in the mitochondrial @genome . It is caused by short tandem repeats (mononucleotide or dinucleotide) of 1 to 6 base pairs that are scattered throughout the mitochondrial genome. These variations can lead to frameshift mutations, which can be caused by @dna polymerase γ, an @enzyme that is responsible for oxidative damage. Mammalian @mitochondria also have an inefficient mismatch repair system, which can lead to @mtmsi formation. The most commonly reported @mtmsi is located in the D-loop region, which is a mutational hotspot in primary tumors. It is a highly polymorphic homopolymeric C stretch, which is involved in R-loop formation, a stable @rna -@dna hybrid that triggers @mtdna replication. D310 alteration has been suggested as a new cancer detection tool and a potential early premalignant @cancermarker . Another potential marker is D16184, which is located in the hypervariable region I and is involved in @mtdna @biogenesis. Studies have reported the presence of D16184 in various @cancer types, such as @gastric and @endometrial @carcinoma . Somatic @mtdna alterations have also been correlated to cancer, with evidence showing that mtDNA changes can contribute to the development or progression of @cancer. One example of a somatic @mtdna alteration is A12308G, which is located in the variable loop next to the anticodon stem of tRNA Leu (CUN). This alteration has been suggested as a potential @diagnostic tool for @Colorectalcancer and as a risk factor for @prostate and @Renalcancer . A10398G has also been studied in relation to cancer, although the results have been conflicting.

Mitochondrial @biomarkers are @molecule s that can be used to detect cancer in its early stages. A commercial kit ( @pcmt ) has been developed to help with this detection. However, even if @cancer is detected early, it can still be difficult to treat if the symptoms have not yet developed. Therefore, researchers are looking into @genetherapy and other mitochondrial interventions as potential treatments for @cancer . They can use current advancements in vitro mitochondrial intervention to identify the @pathogenicity and therapeutic potential of a particular @mtdna @mutation . One method proposed is to transfer artificial healthy @mitochondria to remove damaged @mtdna without @genetic manipulation. Other studies have looked at the levels of @mtdna biomarkers in cancerous and non-cancerous samples, as well as the levels of mtDNA methylation and @mtrna in cancerous tissues.

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Joseph P.

, which is a type of found in , allows for nearly frictionless motion and can absorb large loads. Unfortunately, when it is damaged, it cannot repair itself. is a promising approach to repair the damage, but it falls short of creating functional tissue. This is because the tissue-engineered constructs do not have the same mechanical properties as native articular cartilage, which is due to the insufficient accumulation of matrix components. To address this, researchers have been exploring the use of adenosine triphosphate () to directly harness the underlying mechanotransduction pathways responsible. ATP is a molecule that is released as a result of mechanical stimulation and acts as an autocrine/paracrine signaling . It acts on P2 receptors on the to promote extracellular matrix . However, high doses of ATP can lead to an increase in matrix 13 (MMP-13) activity and extracellular inorganic pyrophosphate (ePPi) accumulation, which can lead to undesirable effects such as of articular cartilage. Therefore, the purpose of this study is to identify the mechanism of ATP-mediated and to determine a therapeutic dose range to maximize the effect.

Materials & Methods

Cell Isolation: This is the process of separating cells from a tissue sample. It is usually done using to break down the tissue and then filtering the cells out.

3-Dimensional Culture: This is a type of where the cells are grown in a three-dimensional environment, rather than in a flat layer. This allows the cells to interact with each other in a more natural way.

Exogenous ATP Supplementation: ATP (adenosine triphosphate) is a molecule that is important for energy production in cells. Exogenous ATP supplementation is the process of adding ATP to the cell culture from an outside source. This can help the cells to grow and function better.

MMP-13 Protein Activity is a type of protein that is found inside cells. It was extracted from 3-D cultured constructs and then frozen and pulverized. It was then homogenized in a buffer solution with a protease inhibitor. After that, it was centrifuged and stored at a low temperature. To measure the amount of active MMP-13, a FRET-based assay was used. This assay uses a fluorophore and quencher to measure the amount of MMP-13 that is present. To measure the amount of ECM synthesis, a range of exogenous ATP doses were used. To measure the effect of PPi on MMP-13 activity, chondrocyte monolayer cultures were established and PPi was added to the cultures. To investigate the underlying mechanisms, inhibitors were added to the cultures. Finally, Transmission Electron (TEM) was used to determine the presence of CPPD accumulation in the engineered tissue constructs. Statistical analyses were then used to analyze the collected data.

The researchers found that when they added ATP to the cultures, MMP-13 activity increased in a dose-dependent manner. This means that the more ATP they added, the more MMP-13 activity increased. They also found that the levels of PPi in the media increased significantly when they added a high dose of ATP, but the levels of PPi in the tissue did not appear to be affected. To determine the best dose of ATP to use, the researchers tested a range of doses and measured the effects on ECM synthesis (collagen and proteoglycans) and MMP-13 activity. They found that ECM synthesis and MMP-13 activity increased in response to intermediate doses of ATP, and further increased in response to higher doses of ATP.

In this study, the researchers wanted to see if they could use ATP to improve tissue growth and mechanical properties without the need for mechanical loading. They found that while high doses of ATP (250 μM) had a positive effect, it also caused a catabolic response, which is when the tissue breaks down. To find the optimal dose of ATP, the researchers tested different doses (31.25, 62.5, and 125 μM) to see which one had the best effect on tissue growth and mechanical properties without causing a catabolic response.

is an important factor in the ATP-mediated catabolism process. The researchers found that when they added 10 μM PPi to cultures, there was a 32% increase in MMP-13 activity compared to unstimulated controls. This effect appeared to require calcium and could be inhibited by the MEK1/2 inhibitor U0126. Additionally, TEM imaging was conducted on engineered cartilaginous tissues supplemented with 0, 62.5 and 250 μM ATP but no mineralization or CPPD crystals were observed which suggests that these doses of ATP did not cause any catabolic response due to crystal formation.

The text is discussing a method of improving tissue growth and mechanical properties of engineered cartilage constructs by applying mechanical loading. However, this approach has limitations when dealing with irregular geometry and high radii of curvature. An alternative approach is to use the known mechanotransduction pathways responsible to achieve the same effect without externally applied forces. In a recent study, it was demonstrated that direct stimulation of the ATP-purinergic receptor pathway through exogenous supplementation of ATP can elicit a comparable anabolic response and be used to improve both tissue growth and mechanical properties of the developed tissue. However, high doses of ATP (250 μM) resulted in a simultaneous catabolic response characterized by an increase in MMP-13 expression, potentially due to the accumulation of ePPi. The present study determined a therapeutic dose range of exogenous ATP to maximize the anabolic response and minimize the catabolic effect of exogenous ATP. It was found that the dose range of ATP between 62.5 and 125 μM was optimal for maximizing the anabolic effect and minimizing the catabolic effect of exogenous ATP. It was also found that calcium and pyrophosphate were key factors involved in the PPi-mediated catabolic response, and that CPPD crystals could potentially be endocytosed and elicit changes through a MAPK-dependent pathway.

The Therapeutic Potential of Exogenous Adenosine Triphosphate (ATP) for Cartilage Tissue Engineering

authors : Jenna Usprech , Gavin Chu , Renata Giardini-Rosa , Kathleen Martin , and Stephen D. Waldman

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Joseph P.

ATP-Driven Molecular Chaperone Machines

are proteins that help maintain the balance of proteins in the , which is essential for the cell to stay alive. Chaperones are always present in the cell, but they can also be activated in response to . They interact with proteins that are not folded correctly, preventing them from clumping together and helping them to fold correctly. Chaperones don't usually interact with proteins that are already folded correctly. They use from binding and/or hydrolysis to help with and unfolding proteins. Because chaperones are involved in keeping protein balance, they are linked to diseases caused by misfolding, such as and . Therefore, understanding how chaperones work is important for understanding and treating these diseases.

The Hsp70 system is a group of proteins that are found in , cells, and some . They are responsible for binding to unfolded or partially unfolded proteins to prevent them from aggregating and to help them fold correctly. Hsp70 proteins are made up of two parts: a 44 kDa N-terminal ATPase domain and a 28 kDa substrate binding domain with a C-terminal lid subdomain. The domain helps the protein bind and release substrates, while the substrate-binding domain binds to extended chains. Hsp40 proteins, which are also known as J-domain proteins, act as co-chaperones to Hsp70 and help recruit substrates and stimulate the ATPase activity of Hsp70. Hsp40s can also direct Hsp70 to specialized functions and sub-cellular regions.

Hsp90 is a type of molecular chaperone that helps proteins fold correctly. It is made up of three conserved domains: the ATP binding N-terminal domain, the middle domain, and the C-terminal dimerization domain. Hsp90 works by binding to proteins that need to be folded correctly and preventing them from aggregating in an ATP-dependent manner. It also interacts with other proteins, called co-chaperones, which help regulate its ATPase cycle and determine which proteins it binds to. Hsp90 can also act as a buffer for genetic variation by rescuing mutated proteins with altered properties.

The different functions of the Hsp100/Clp proteins.

These proteins contain one or two conserved ATPases Associated with various cellular Activities (AAA1) domains and can act as or . Unfoldases help to unfold proteins and deliver them to a ring , while disaggregases have the unique ability to recover proteins from both amorphous and aggregates. The main difference between the two is the presence of a coiled-coil insertion in the first AAA1 domain in the disaggregases. The Hsp100 proteins usually form hexamers which hydrolyze ATP in either a sequential/random or a concerted manner. structures have been determined of monomeric forms of several Hsp100 proteins, and of the hexamer forms of HslU, ClpX, and ClpC unfoldases. Hexameric forms of various Hsp100’s have been observed at intermediate resolutions by cryo-EM. These structures suggest a typical AAA1 packing arrangement for the unfoldases and an expanded conformation for the Hsp104 disaggregase. The central channels of the Hsp100s are lined by tyrosine residues, located on mobile loops, which bind substrates non-specifically. It is thought that rotations of the AAA1 domains provide the force to unfold the bound substrate and pull it through the channel. Disaggregation and unfolding functions are coupled and regulated via an interaction between the Hsp70 nucleotide-binding domain and the coiled-coil insertion. Recent biochemical and structural data suggest that it is docked on the outside surface of the AAA1 ring. Hsp100/Clp proteins are proteins that have one or two conserved ATPases Associated with various cellular Activities (AAA1) domains. These proteins can act in two different ways: as unfoldases or disaggregases. Unfoldases help to unfold proteins and deliver them to a ring protease, while disaggregases have the ability to recover proteins from both amorphous and amyloid aggregates. The main difference between the two is the presence of a coiled-coil insertion in the first AAA1 domain in the disaggregases. The Hsp100 proteins usually form hexamers which hydrolyze ATP in either a sequential/random or a concerted manner. Structures of these proteins have been determined, which suggest a typical AAA1 packing arrangement for the unfoldases and an expanded conformation for the Hsp104 disaggregase. The central channels of the Hsp100s are lined by tyrosine residues, which bind substrates non-specifically. It is thought that rotations of the AAA1 domains provide the force to unfold the bound substrate and pull it through the channel. Disaggregation and unfolding functions are coupled and regulated via an interaction between the Hsp70 nucleotide-binding domain and the coiled-coil insertion, which is docked on the outside surface of the AAA1 ring.

GroEL is a molecular chaperone machine that binds to proteins to prevent them from aggregating. It is estimated that GroEL binds to around 10% of the proteins in E. coli. The binding site is hydrophobic in character and contains essential hydrophobic residues that line the cavity-facing surface of the apical domain. If one of these residues is changed from hydrophobic to hydrophilic, the binding is abolished. Studies have shown that multiple binding sites act together as a continuous hydrophobic binding surface. It has also been shown that proteins stably bound to are unstructured and that binding of non-native proteins to GroEL can be associated with unfolding. X-ray crystallographic studies have revealed structures of extended or helical peptides bound in the groove formed by helices H and I via hydrophobic interactions. Cryo-EM has also been used to probe the structure of non-native proteins bound to GroEL, which showed that the substrates were bound to helices H and I, with substrate density protruding from the GroEL ring. There is an upper limit, around 60 kDa, to the size of substrate that can fit inside the folding chamber. In summary, GroEL is a molecular chaperone machine that binds to proteins to prevent them from aggregating. It has a hydrophobic binding site that contains essential hydrophobic residues. Studies have shown that multiple sites act together as a continuous hydrophobic binding surface and that proteins stably bound to GroEL are unstructured. X-ray crystallographic and cryo-EM studies have revealed structures of extended or helical peptides bound in the groove formed by helices H and I via hydrophobic interactions. The upper limit to the size of substrate that can fit inside the folding chamber is around 60 kDa.

Structural, biochemical, and biophysical studies have shown how proteins interact with GroEL, a protein-folding machine, and how ATP (a molecule that provides energy for many processes in cells) induces changes in GroEL's shape that allow it to switch between binding to proteins and folding them. Mutational analysis and cryo-EM studies (a type of imaging technique) have revealed that proteins primarily bind to a specific part of GroEL, and that multiple parts of GroEL bind to the protein at the same time. This binding causes the parts of GroEL to extend and expand, which helps to unfold the protein. Additionally, the protein's binding to GroEL provides a mechanical load on GroEL, which helps to further unfold the protein. Finally, when ATP is added, the parts of GroEL rotate, which removes the binding sites from the inside of the chamber and traps the protein in the chamber, which is now capped by GroES (another protein-folding machine). Group 2 are similar to GroEL, but have a slightly different structure. They are found in both eukaryotes (organisms with a nucleus, like humans) and archaea (a type of single-celled organism). They form back-to-back rings and have a high degree of sequence identity/similarity to GroEL. The main difference is an extension in the part of GroEL that forms the lid of the folding chamber. This extension helps to further unfold the protein.

The structural similarities between the Group 2 chaperonins and GroEL, both essential for folding proteins. Group 2 chaperonins have 8- or 9-fold symmetry, meaning that they form back-to-back rings with the same domain structure and a high degree of sequence identity/similarity to GroEL. The main difference between the two is an extension in the helix H equivalent in the apical domain of the Group 2 chaperonin, which removes the need for a GroES co-chaperone. Structural studies of the Group 2 chaperonins in different nucleotide bound states have revealed open, substrate binding and closed, substrate folding conformations similar to GroEL. These conformations involve a large clockwise twist of the apical domains and an inward tilt of the whole subunit, which brings the catalytic Asp in the intermediate domain close to the ATP binding site and closes the folding chamber. The ring expansion/contraction of Group 2 chaperonins is facilitated by the 1:1 nature of their inter-ring interface, allowing the equatorial domains to move more freely than in GroEL.

ATP-driven chaperones are proteins that help other proteins maintain their structure and function. They do this by binding, unfolding, refolding, and disaggregating proteins that are not in their native state. The Hsp70 system uses ATP binding and hydrolysis to regulate the binding and release of substrates. It is also regulated by co-chaperones. Hsp90 uses its ATPase cycle to induce multiple conformations that bind and stabilize or help mature the substrate proteins. It is also regulated by co-chaperones. The Hsp100s use ATP to unfold, thread, and disaggregate substrate proteins. In ATP-dependent proteolysis, the unfoldase is connected to a protease which breaks down the unfolded substrate proteins. The disaggregases, in combination with the Hsp70 system, use ATP-induced conformational changes to disaggregate and unfold substrate proteins. GroEL-GroES uses ATP binding to induce conformational changes to convert from a substrate binding to a substrate folding complex. It may also use the ATP-induced conformational changes to force the substrate to unfold. GroES binding then ejects the substrate from the binding surface, giving it a chance to fold in isolation during the slow ATP hydrolysis step. The archaeal Group 2 chaperonins use ATP-induced domain rotations that are similar to GroEL, but the conformational changes are not in the same order. The eukaryotic cytosol Group 2 chaperonin is similar to the archaeal system, but its ATPase cycle and action appear to be more complex and specific to the substrate.

In conclusion, ATP-driven chaperones are proteins that help other proteins maintain their structure and function by binding, unfolding, refolding, and disaggregating proteins that are not in their native state. Structural studies of GroEL and Group 2 chaperonins have revealed ATP-induced conformational changes that bind, unfold, and refold proteins in the ATP-dependent folding process. GroEL uses ATP binding to induce a conformational change that switches between the substrate binding and substrate folding states. The archaeal Group 2 chaperonins have a similar mechanism, but with a different order of conformational changes. The eukaryotic cytosol Group 2 chaperonin is more complex, indicating different substrate-specific functions. In general, ATP-driven chaperones help to ensure the proper folding of proteins and support the lifecycle of proteins.

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Joseph P.

Solidarity with those fighting to get their servers back up and running . Good luck to all the federation servers fighting the good fight :rocket:

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Joseph P.

Mefisto from team has hacked a major film streaming service in to bring them the truth of the kremlin’s Ukrainian genocide and colonial war of choice

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Joseph P.

Wedding cost and size impact of divorce rates .

I’m in a low cost low attendance wedding couple😅

What about you ?

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Joseph P.

@smadre75 i just did it for me, so basically when you go to block you'll get an option, just block account or block entire domain. since there's only two accounts on that domain, it's no sweat off my back :-)

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Joseph P.

Russia is getting back to the stone age - it's really a never-been-seen-before level of sophistication and federation of civilian actors . the talent here is huge, the security here is the importance of bringing consequences to the invaders while eroding their misplaced belief in the exceptionalism of their security will start to get folks thinking, let's hope.

Show thread
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Joseph P.

From Team :

"Today we announce a first in history - striking an operational /#ML () model, in addition to a /#ICS!
This is Op.Neutrino, an electrical counterattack against , , and now, it's story is here

At 17:00 local time, we assumed control over an
@EnstoGroup
belonging to the DK Port substation. Timing was chosen to match peak usage hours. In addition to controlling power supply, it was supplying data for Rosenergo's FLISR fault

From the controller, we successfully fed bad data into the FLISR model, via the connected sensors. Then, we nuked it!
Every attack against will be avenged, every model will be corrupted! 🇺🇦☢️👊

One last message: if you enjoy reading about our operations, I would like to ask you to donate at

onefist.org/donate.

We have been self funded for the entirety of this war, but it isn't enough for the equipment we need for war. Anything you can spare helps! Thank you :) "

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cell

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biomanufacturing

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heart

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biofabrication

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neuro There is nothing here!

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eye There is nothing here!

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proteomics There is nothing here!

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omics There is nothing here!

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genomics There is nothing here!

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