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What does pseudo-irreversible mean?

What does pseudo-irreversible mean?


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Binding of rupatadine to histamine H1 receptors isolated from the guinea-pig cerebellum and lung was demonstrated by inhibition of 3H-mepyramine binding; equilibrium inhibition constant (affinity) [Ki] values were 26-256 nM in the various experiments. Binding was time-dependent and pseudo-irreversible. Rupatadine was ~7.5 and 10-times more potent than the structurally-related anti-histamines loratadine and fexofenadine. H1 receptor occupation by rupatadine in guinea-pig cerebellum and lung after oral (PO) dosing was relatively rapid (with maximum binding evident at 2-4 hours post-dose) and dose-dependent; low or no binding was seen at 48 hours post-dose.

In this context, what does pseudo-irreversible mean? Since it goes on to say the binding had dissipated within 48 hours, it seems to mean persistent or long-lived. Is that correct or does it have a more specific meaning in biology?


it seems to mean persistent or long-lived. Is that correct… ?

Yes, it's correct, but how persistent the effect is is related to the rate of dissociation or rate of turnover of the receptor. It is relative, so to speak; relative to the effect of non-irreversible receptor binding.

Irreversible inhibition of, say, a cell surface receptor means that a drug (agonist/antagonist) binds permanently to the target receptor, usually by binding covalently; the chemical reaction is not reversible. This isn't synonymous with a permanent effect on a cell or organism; that depends on turnover of the receptor. A "faulty" receptor may be replaced quite quickly or not; it depends of the cell and the receptor.

Pseudo-irreversible means that the drug acts in a manner similar to irreversibly bound agonists/antagonists, but there is no covalent bond formed; if a drug/molecule which has a sufficiently high affinity for the receptor is introduced (in a sufficiently high quantity), the new molecule will replace that which was strongly bound before (the pseudo-irreversibly bound drug.)

Some of these types of reactions have been studied more than others. One example of this can be seen with h5-HT7 receptors, which are subject to pseudo-irreversible inactivation by risperidone and 9-OH-risperidone.

Clozapine and other competitive antagonists reactivate risperidone-inactivated h5-HT7 receptors: radioligand binding and functional evidence for GPCR homodimer protomer interactions


Truncated

Truncated means shortened, as if having had a portion cut off.

The verb truncate means to shorten something in this way.

As an adjective, truncated can be used in several specialized ways, all of which describe things that have been shortened or seem like they’ve been shortened or cut off.

In geometry, it’s used to describe a shape that has had one of its parts or corners cut off. In crystallography, it’s used to describe a crystal whose corners, angles, or edges are cut off. In biology, it’s used to describe a part of an organism, such as the leaf of a plant, that looks like it has been cut off at the tip. In poetry, it’s used to describe a line that has fewer syllables that the meter (the rhythm of the line) suggests it should.

Still, truncated is most commonly used in a general way. A more common and less formal synonym is shortened.

Example: Most people have only ever seen the truncated version of the film, but they’re planning to release the full version soon.


What does it mean I have a monoclonal B-cell lymphocytosis?: Recent insights and new challenges

Monoclonal B-cell lymphocytosis (MBL) is defined as a laboratory abnormality where small (<5 x 10(9)/L) clonal B-cell populations are detected in the peripheral blood of otherwise healthy subjects. According to the immunophenotype, MBL is labeled as chronic lymphocytic leukemia (CLL)-like (75% of cases), atypical CLL, and CD5-negative. Concentration of clonal B cells differentiates low- (LC) and high-count (HC)-MBL (< or ≥ 0.5 x 10(9)/L, respectively). Thanks to technical improvements, we are able to identify CLL-like clonal B-cell populations at increased frequency with age, but we are still far from understanding its relationship with clinically overt CLL. LC-MBL, requiring high-throughput screening technique to be identified in population studies, seems to be a bird of a different feather and several hints suggest that LC-MBL is related to aging and/or chronic antigenic stimulation. Immunogenetic, cytogenetic and genetic data support the notion that HC-MBL, usually identified in the clinical setting, is a premalignant condition and, based on biological parameters, it is frequently difficult to differentiate it from early stage CLL. The rapid improvement and widespread availability of cutting-edge technology, in particular next-generation sequencing (NGS), raises hope that we are getting closer to unveiling the fundamental nature of MBL and CLL and how they are related to each other.

Keywords: Chronic lymphocytic leukemia Cytogenetic Immunoglobulin genes Monoclonal B-cell lymphocytosis Next-generation sequencing.


How race becomes biology: embodiment of social inequality

The current debate over racial inequalities in health is arguably the most important venue for advancing both scientific and public understanding of race, racism, and human biological variation. In the United States and elsewhere, there are well-defined inequalities between racially defined groups for a range of biological outcomes-cardiovascular disease, diabetes, stroke, certain cancers, low birth weight, preterm delivery, and others. Among biomedical researchers, these patterns are often taken as evidence of fundamental genetic differences between alleged races. However, a growing body of evidence establishes the primacy of social inequalities in the origin and persistence of racial health disparities. Here, I summarize this evidence and argue that the debate over racial inequalities in health presents an opportunity to refine the critique of race in three ways: 1) to reiterate why the race concept is inconsistent with patterns of global human genetic diversity 2) to refocus attention on the complex, environmental influences on human biology at multiple levels of analysis and across the lifecourse and 3) to revise the claim that race is a cultural construct and expand research on the sociocultural reality of race and racism. Drawing on recent developments in neighboring disciplines, I present a model for explaining how racial inequality becomes embodied-literally-in the biological well-being of racialized groups and individuals. This model requires a shift in the way we articulate the critique of race as bad biology.


Why Practice It?

Social connections are one of the single biggest predictors of personal well-being, and there is some evidence that making your network of connections rich and diverse can also contribute to health, success, and happiness.

  • Many studies have found that diverse organizations outperform their non-diverse counterparts. For example, when researchers studied the gender composition of management teams of the top firms in Standard & Poor’s Composite 1500 list, they found that, on average, “female representation in top management leads to an increase of $42 million in firm value.”
  • Economic diversity matters as well. Several studies suggest that contact across social classes seems to influence well-being and prosocial behaviors like gratitude and generosity. This research suggests it’s bad for everyone’s well-being when the rich don’t have contact with the poor, or the poor with the middle class.
  • Prejudice hurts the health of both targets and (to a different degree) perpetrators. The targets of prejudice experience the well-documented “weathering effect” on their physical and mental health. On the other side, manystudies suggest that people who discriminate are at much greater risk of cardiovascular disease. Fortunately, interracial interactions needn’t be stressful. In many of the same studies, low-prejudice people respond to interracial interactions in ways that are happy and healthy.
  • Prejudice against students by educators hurts their academic achievement. At the same time, research to date suggests student achievement is higher in diverse schools.
  • Implicit and explicit prejudice fuel incredible disparities in the criminal justice system at every level. For example, a study led by Jennifer Eberhardt of Stanford University found that black men convicted of capital crimes are more than twice as likely to be sentenced to death if they have facial features deemed to be more stereotypically “black-looking.”
  • One 2014 study in the journal Psychological Science suggests that people who play more diverse social roles may be better able to perceive and decode nonverbal cues in a variety of social settings. In other words, this result suggests, social and emotional intelligence rises as we interact with more kinds of people.
  • Finally, separation fuels intergroup discrimination, conflict, and violence—while embracing diversity seems to reduce it. People who live in homogenous communities, who have few opportunities for contact with outside groups, tend to resist diversity, which in turn seems to negatively affect their well-being.

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Quorum sensing

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Quorum sensing, mechanism by which bacteria regulate gene expression in accordance with population density through the use of signal molecules. Quorum sensing allows bacteria populations to communicate and coordinate group behaviour and commonly is used by pathogens (disease-causing organisms) in disease and infection processes. Bacterial activity involving quorum sensing was first observed in the mid-1960s by Hungarian-born microbiologist Alexander Tomasz in his studies of the ability of Pneumococcus (later known as Streptococcus pneumoniae) to take up free DNA from its environment.

Standard quorum-sensing pathways consist of bacteria populations, signal molecules, and behavioral genes. The signal molecules, known as autoinducers, are secreted into the environment by bacteria and gradually increase in concentration as the bacteria population grows. After reaching a certain concentration threshold, the molecules become detectable to bacteria populations, which then activate corresponding response genes that regulate various behaviours, such as virulence, horizontal gene transfer, biofilm formation, and competence (the ability to take up DNA). Since many of these processes are effective only at certain population sizes, quorum sensing is a key behaviour-coordination mechanism in many microbes.

Although quorum sensing is common among bacteria, the precise sensing system and class of quorum-sensing compounds used may differ. In addition, the manner in which different types of bacteria apply quorum sensing varies greatly. For example, the bacterium Pseudomonas aeruginosa, which can cause pneumonia and blood infections, uses quorum sensing to regulate disease mechanisms. By remaining relatively harmless until population sizes are sufficient, the bacteria are able to overwhelm host defenses with the activation of genes regulating biofilm formation and virulence. In other organisms, quorum sensing is used for symbiotic processes and cell growth an example is the nitrogen-fixation mechanism of the bacterium Rhizobium leguminosarum.

The communication abilities offered by quorum sensing are highly useful for bacteria because they allow bacteria populations to acquire traits found in plants, animals, and other higher-level organisms. These abilities, including group communication and behaviour synchronization, allow bacteria populations to develop more quickly, gain access to more resources, and secure better chances of survival. Pathogens with quorum-sensing pathways may also infect host organisms more effectively, leading to deadlier diseases. As a result, to help kill or prevent infection by microbes that use quorum-sensing strategies, new ways of supplementing host defenses must be identified.

On the macroscopic scale, mechanisms similar to quorum sensing can be observed in organisms such as ants and bees. Quorum-sensing strategies may also be applied to robotics and computer technology in sensors, self-organizing networks, and robot swarms. These technologies may be used for various applications, including coordinating medical nanobots in treatments and organizing humanoid robots for manufacturing and other processes.


Examples of centi-

One example of a term featuring centi- that you may have encountered is centimeter, “one 100th of a meter.”

The centi- part of the word here means “hundredth,” as used in units of measure. The -meter part in this word refers to meter, “the fundamental unit of length in the metric system.” Centimeter literally means “a hundredth of a meter.”

Centimeter comes from the French centimètre, which uses the equivalent form of centi- in the language.

What are some words that use the combining form centi-?

Most of the following forms feature the equivalent forms of centi- in French or Latin.

What are some other forms that centi- may be commonly confused with?


Morphology

“The mosasaurs were still experimenting with new ways of feeding, new morphologies, new lifestyles just before that asteroid came down,” Longrich says.

The morphology of the canine was so similar to a mega-size gray wolf that nobody thought to argue with what seemed like a sure thing.

Still, structure and function go hand-in-hand in biology, so it’s reasonable to expect one day neuroscientists will know how specific neuronal morphologies contribute to activity profiles.

In one, rapid diversification in some aspect of body morphology produces a burst of new species at first, and then speciation slows as the available niches fill up.

Keefe recently published a paper in the Biological Journal of the Linnean Society on the morphology of 89 species of frogs from every continent except Antarctica.

Recognition of the pneumococcus depends upon its morphology , the fact that it is Gram-staining, and the presence of a capsule.

Functional morphology of three bats: Sumops, Myotis, Macrotus.

Their influence reaches far beyond the proper sphere of phonetics and invades that of morphology , as we shall see.

Although it is as an anatomist that Nehemiah Grew is best known, his grasp of external morphology is perhaps even more remarkable.

We must recollect that the comparative morphology of the ovule (in the wide sense) was not attempted.


Etiology is a formal, technical word that’s primarily used in medicine, but it can be used in other contexts as well.

Dementia is a general observation of mental decline available to any sharp observer. You need the MD to diagnose this condition’s etiology. There are MANY possible causes of dementia.

&mdash Horse Sense (@mabian) March 9, 2020

Although the exact etiology, or cause, of stuttering is unknown, both genetics and neurophysiology are thought to contribute.

&mdash Stutter No More (@StutterNoMore) April 8, 2020

“If the Jew did not exist, the anti-Semite would invent him.”
― Jean-Paul Sartre, Anti-Semite and Jew: An Exploration of the Etiology of Hate

&mdash ZahnZee (@Zahn_Zee) April 6, 2020


Diagnosis and Treatment of Hallucinations

First, your doctor needs to find out what's causing your hallucinations. They'll ask about your medical history and do a physical exam. Then they'll ask about your symptoms.

Continued

They may need to do tests to help figure out the problem. For instance, an EEG, or electroencephalogram, checks for unusual patterns of electrical activity in your brain. It could show if your hallucinations are due to seizures.

You might get an MRI, or magnetic resonance imaging, which uses powerful magnets and radio waves to make pictures of the inside of your body. It can find out if a brain tumor or something else, like an area that's had a small stroke, could be to blame.

Your doctor will treat the condition that's causing the hallucinations. This can include things like:

  • Medication for schizophrenia or dementias like Alzheimer's disease
  • Antiseizure drugs to treat epilepsy
  • Treatment for macular degeneration, glaucoma, and cataracts
  • Surgery or radiation to treat tumors
  • Drugs called triptans, beta-blockers, or anticonvulsants for people with migraines

Your doctor may prescribe pimavanserin (Nuplazid). This medicine treats hallucinations and delusions linked to psychosis that affect some people with Parkinson’s disease.

Sessions with a therapist can also help. For example, cognitive behavioral therapy, which focuses on changes in thinking and behavior, helps some people manage their symptoms better.

Sources

The Primary Care Companion to the Journal of Clinical Psychiatry: "Visual hallucinations: differential diagnosis and treatment."

Current Psychiatry: "Hallucinations: Common features and causes."

National Institute of Mental Health: "Schizophrenia."

Alzheimer's Association: "Hallucinations and Alzheimer's."

Annals of Emergency Medicine: "Olfactory and Gustatory Hallucinations Presenting as Partial Status Epilepticus Because of Glioblastoma Multiforme."

Progress in Neurology and Psychiatry: "Causes, diagnosis and treatment of visceral hallucinations."

Mental Health Foundation: “Hearing voices.”

Psychological Medicine: “Auditory hallucinations, not necessarily a hallmark of psychotic disorder.”

MentalHelp.Net: “Drug-Induced Psychotic Symptoms.”

Primary Care Companion to The Journal of Clinical Psychiatry: “Visual Hallucinations: Differential Diagnosis and Treatment.”

Mayo Clinic: “Phantosmia: What causes olfactory hallucinations?”

Current Psychiatry: “Hallucinations: Common features and causes.”

Brain: “Gustatory hallucinations in epileptic seizures. Electrophysiological, clinical and anatomical correlates.”

Industrial Psychiatry Journal: “Hallucinations: Clinical aspects and management.”