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Topic Review
Effects of Stress on Memory
The effects of stress on memory include interference with a person's capacity to encode memory and the ability to retrieve information. During times of stress, the body reacts by secreting stress hormones into the bloodstream. Stress can cause acute and chronic changes in certain brain areas which can cause long-term damage. Over-secretion of stress hormones most frequently impairs long-term delayed recall memory, but can enhance short-term, immediate recall memory. This enhancement is particularly relative in emotional memory. In particular, the hippocampus, prefrontal cortex and the amygdala are affected. One class of stress hormone responsible for negatively affecting long-term, delayed recall memory is the glucocorticoids (GCs), the most notable of which is cortisol. Glucocorticoids facilitate and impair the actions of stress in the brain memory process. Cortisol is a known biomarker for stress. Under normal circumstances, the hippocampus regulates the production of cortisol through negative feedback because it has many receptors that are sensitive to these stress hormones. However, an excess of cortisol can impair the ability of the hippocampus to both encode and recall memories. These stress hormones are also hindering the hippocampus from receiving enough energy by diverting glucose levels to surrounding muscles. Stress affects many memory functions and cognitive functioning of the brain. There are different levels of stress and the high levels can be intrinsic or extrinsic. Intrinsic stress level is triggered by a cognitive challenge whereas extrinsic can be triggered by a condition not related to a cognitive task. Intrinsic stress can be acutely and chronically experienced by a person. The varying effects of stress on performance or stress hormones are often compared to or known as "inverted-u" which induce areas in learning, memory and plasticity. Chronic stress can affect the brain structure and cognition. Studies considered the effects of both intrinsic and extrinsic stress on memory functions, using for both of them Pavlovian conditioning and spatial learning. In regard to intrinsic memory functions, the study evaluated how stress affected memory functions that was triggered by a learning challenge. In regard to extrinsic stress, the study focused on stress that was not related to cognitive task but was elicited by other situations. The results determined that intrinsic stress was facilitated by memory consolidation process and extrinsic stress was determined to be heterogeneous in regard to memory consolidation.[clarification needed] Researchers found that high stress conditions were a good representative of the effect that extrinsic stress can cause on memory functioning.[clarification needed] It was also proven that extrinsic stress does affect spatial learning whereas acute extrinsic stress does not.[clarification needed]
  • 1.3K
  • 27 Oct 2022
Topic Review
Flashback (Psychology)
A flashback, or involuntary recurrent memory, is a psychological phenomenon in which an individual has a sudden, usually powerful, re-experiencing of a past experience or elements of a past experience. These experiences can be happy, sad, exciting, or of any other emotion one can consider. The term is used particularly when the memory is recalled involuntarily, and/or when it is so intense that the person "relives" the experience, unable to fully recognize it as memory and not something that is happening in "real time".
  • 1.3K
  • 22 Nov 2022
Topic Review
Hemagglutinin (Influenza)
Influenza hemagglutinin (HA) or haemagglutinin[p] (British English) is a glycoprotein found on the surface of influenza viruses. Being a class I fusion protein, it is responsible for binding the virus to cells with sialic acid on the membranes, such as cells in the upper respiratory tract or erythrocytes. It is also responsible for the fusion of the viral envelope with the endosome membrane, after the pH has been reduced. The name "hemagglutinin" comes from the protein's ability to cause red blood cells (erythrocytes) to clump together ("agglutinate") in vitro.
  • 1.3K
  • 09 Nov 2022
Topic Review
EAPCRN
The East Asian Primary Care Research Network (EAPCRN), initially proposed by Professor Jae-Ho Lee who is the Chairman of the Korean Primary Care Research Group, was officially established during the 22nd World Organization of Family Doctors (WONCA) World Conference – "Primary Care in the Future: Professional Excellence" during 17-21 October 2018 in Seoul, South Korea. The EAPCRN inauguration seminar at WONCA Seoul 2018 was convened by Jae-Ho Lee (Korean Primary Care Research Group; The Catholic University of Korea) and co-convened by Harry H.X. Wang (Sun Yat-Sen University), Takuya Aoki (Kyoto University), and Chyi-Feng Jan (National Taiwan University).
  • 1.3K
  • 05 Nov 2020
Topic Review
Imprinted Brain Theory
The imprinted brain theory is an evolutionary psychology theory regarding the causes of autism spectrum disorders and psychosis. In certain ways, autistic traits are the opposite of schizotypal traits, such as autism being associated with literal-mindedness while schizotypy is associated with imagination. These differences tend to resemble sex differences, such as autism being linked to larger brain size and schizotypy to slower brain growth. Bernard Crespi proposes that these tendencies show that autism is linked to epigenetic imprinting of the X chromosome by the father, in the case of autism, or by the mother, in the case of psychosis.
  • 1.3K
  • 08 Oct 2022
Topic Review
Burn Size Assessment
In burn medicine, the percentage of the burned body surface area (TBSA-B) to the total body surface area (TBSA) is a crucial parameter to ensure adequate treatment and therapy. Inaccurate estimations of the burn extent can lead to wrong medical decisions resulting in considerable consequences for patients. These include, for instance, over-resuscitation, complications due to fluid aggregation from burn edema, or non-optimal distribution of patients. Due to the frequent inaccurate TBSA-B estimation in practice, objective methods allowing for precise assessments are required. 
  • 1.3K
  • 10 May 2021
Topic Review
Adjustment Disorder
Adjustment disorder (AjD) is a mental and behavioral disorder, which is a maladaptive response to a psychosocial stressor that occurs when an individual has significant difficulty adjusting to or coping with a stressful psychosocial event. The maladaptive response usually involves otherwise normal emotional and behavioral reactions that manifest more intensely than usual (taking into account contextual and cultural factors), causing marked distress, preoccupation with the stressor and its consequences, and functional impairment. Diagnosis of AjD is quite common; there is an estimated incidence of 5–21% among psychiatric consultation services for adults. Adult women are diagnosed twice as often as are adult men. Among children and adolescents, girls and boys are equally likely to receive this diagnosis.:681 AjD was introduced into the Diagnostic and Statistical Manual of Mental Disorders in 1980. Prior to that, it was called "transient situational disturbance."
  • 1.3K
  • 17 Oct 2022
Topic Review
MT1-MMP in Cancer Progression
For over 20 years, membrane type 1 matrix metalloproteinase (MT1-MMP) has been recognized as a key component in cancer progression. Initially, the primary roles assigned to MT1-MMP were the activation of proMMP-2 and degradation of fibrillar collagen. Proteomics has revealed a great array of MT1-MMP substrates, and MT1-MMP selective inhibitors have allowed for a more complete mapping of MT1-MMP biological functions. MT1-MMP has extensive sheddase activities, is both a positive and negative regulator of angiogenesis, can act intracellularly and as a transcription factor, and modulates immune responses. We presently examine the multi-faceted role of MT1-MMP in cancer, with a consideration of how the diversity of MT1-MMP behaviors impacts the application of MT1-MMP inhibitors.
  • 1.3K
  • 30 Oct 2020
Topic Review
Inflammation in TGFβ-Dependent EMT
Epithelial–mesenchymal transition (EMT) is a complex cellular program known to be a crucial driver in the context of embryonic development, wound healing and tumour progression.
  • 1.3K
  • 03 Mar 2021
Topic Review
Genetics of Amyotrophic Lateral Sclerosis
Amyotrophic lateral sclerosis (ALS) is the most frequent motor neuron disease and a neurodegenerative disorder, affecting the upper and/or lower motor neurons. Notably, it invariably leads to death within a few years of onset. Although most ALS cases are sporadic, familial amyotrophic lateral sclerosis (fALS) forms 10% of the cases. In 1993, the first causative gene (SOD1) of fALS was identified. With rapid advances in genetics, over fifty potentially causative or disease-modifying genes have been found in ALS so far. Accordingly, routine diagnostic tests should encompass the oldest and most frequently mutated ALS genes as well as several new important genetic variants in ALS.
  • 1.3K
  • 07 Jan 2021
Topic Review
Services for Mental Disorders
Services for mental health disorders provide treatment, support, or advocacy to people who have psychiatric illnesses. These may include medical, behavioral, social, and legal services. Medical services are usually provided by mental health experts like psychiatrists, psychologists, and behavioral health counselors in a hospital or outpatient clinic. Behavioral services go hand-in-hand with medical services, referring specifically to pharmacological and cognitive therapy. Social services are usually provided by the government or nonprofit organizations. They arrange housing options, job training, or other community resources overseen by experienced professionals to ensure overall productivity and well being of individuals with mental illnesses. Legal services ensure that people with mental health disorders are not discriminated against in society and advocate for their basic human rights. In addition, legal services make sure that those individuals who might be a danger to themselves or others are diverted away from the judicial system to receive adequate treatment for underlying mental health issues. The information provided below is primarily regarding services offered within the United States of America, unless otherwise specified.
  • 1.3K
  • 10 Oct 2022
Topic Review
Dual-Energy Computed Tomography of Liver
Dual-energy computed tomography (DECT) is an imaging technique based on data acquisition at two different energy settings. Recent advances in CT have allowed data acquisitions and simultaneous analyses of X-rays at two energy levels, and have resulted in novel developments in the field of abdominal imaging. The use of low and high X-ray tube voltages in DECT provide fused images that improve the detection of liver tumors owing to the higher contrast-to-noise ratio (CNR) of the tumor compared with the liver. The use of contrast agents in CT scanning improves image quality by enhancing the CNR and signal-to-noise ratio while reducing beam-hardening artifacts. DECT can improve detection and characterization of hepatic abnormalities, including mass lesions. The technique can also be used for the diagnosis of steatosis and iron overload.
  • 1.2K
  • 12 Oct 2021
Topic Review
TKS4 and TKS5 Scaffold Proteins
Scaffold proteins are typically thought of as multi-domain “bridging molecules.” They serve as crucial regulators of key signaling events by simultaneously binding multiple participants involved in specific signaling pathways. In the case of epidermal growth factor (EGF)-epidermal growth factor receptor (EGFR) binding, the activated EGFR contacts cytosolic SRC tyrosine-kinase, which then becomes activated. This process leads to the phosphorylation of SRC-substrates, including the tyrosine kinase substrates (TKS) scaffold proteins. The TKS proteins serve as a platform for the recruitment of key players in EGFR signal transduction, promoting cell spreading and migration. The TKS4 and the TKS5 scaffold proteins are tyrosine kinase substrates with four or five SH3 domains, respectively. Their structural features allow them to recruit and bind a variety of signaling proteins and to anchor them to the cytoplasmic surface of the cell membrane. TKS4 and TKS5 had been recognized for their involvement in cellular motility, reactive oxygen species-dependent processes, and embryonic development. Furthermore, TKS4 has also been implicated in the regulation of homeostasis of mature adipose and bone tissue.
  • 1.2K
  • 19 Jan 2021
Topic Review
CRAFFT Screening Test
The CRAFFT Screening Test is a short clinical assessment tool designed to screen for substance-related risks and problems in adolescents. CRAFFT stands for the key words of the 6 items in the second section of the assessment - Car, Relax, Alone, Forget, Friends, Trouble. As of 2016, an updated version of the CRAFFT known as the “CRAFFT 2.0” has been released. The older version of the questionnaire contains 9 items in total, answered in a "yes" or "no" format. The first three items (Part A) evaluate alcohol and drug use over the past year and the other six (Part B) ask about situations in which the respondent used drugs or alcohol and any consequences of the usage. The CRAFFT 2.0 screening tool begins with past-12-month frequency items (Part A), rather than the previous “yes/no” question for any use over the past year and the other six (Part B) ask about situations in which the respondent used drugs or alcohol and any consequences of usage. The CRAFFT can function as a self-report questionnaire or an interview to be administered by a clinician. Both employ a skip pattern: those whose Part A score is "0" (no use) answer the Car question only of Part B, while those who report any use in Part A also answer Part B's five CRAFFT questions. Each "yes" answer is scored as "1" point and a CRAFFT total score of two or higher identifies "high risk" for a substance use disorder and warrants further assessment.
  • 1.2K
  • 25 Nov 2022
Topic Review
Oxidative Stress in CKD
Oxidative stress is important in the development and progression of diabetic nephropathy (DN). Many pathways and molecules are involved in the induction of oxidative stress in DN. The identification of biomarkers of oxidative stress contibutes to our understanding of development and progression of DN towards end-stage reanal disease.
  • 1.2K
  • 06 Nov 2020
Topic Review
Adaptive Design
In an adaptive design of a clinical trial, the parameters and conduct of the trial for a candidate drug or vaccine may be changed based on an interim analysis. Adaptive design typically involves advanced statistics to interpret a clinical trial endpoint. This is in contrast to traditional randomized clinical trials (RCTs) that are static in their protocol and do not modify any parameters until the trial is completed. The adaptation process generally continues throughout the trial, as prescribed in the trial protocol. Adaptions may include modifications to: dosage, sample size, drug undergoing trial, patient selection criteria and/or "cocktail" mix. The PANDA (A Practical Adaptive & Novel Designs and Analysis toolkit) provides comprehensive summary of different adaptive designs. In some cases, trials have become an ongoing process that regularly adds and drops therapies and patient groups as more information is gained. Importantly, the trial protocol is set before the trial begins which pre-specifies the adaptation schedule and processes.
  • 1.2K
  • 09 Oct 2022
Topic Review
Percutaneous Vertebroplasty
Vertebroplasty and kyphoplasty are similar medical spinal procedures in which bone cement is injected through a small hole in the skin (percutaneously) into a fractured vertebra with the goal of relieving back pain caused by vertebral compression fractures. It was found not to be effective in treating osteoporosis-related compression fractures of the spine. The people in both the experimental and placebo groups of the blinded study reported improvement in their pain, suggesting that the benefit noted in unblinded trials is related to the placebo effect. The cost of vertebroplasty in Europe as of 2010 was ~2,500 Euro. As of 2010 in the United States, when done as an outpatient, vertebroplasty costs around 3300 USD while kyphoplasty costs around 8100 USD and when done as an inpatient vertebroplasty cost ~11,000 USD and kyphoplasty 16,000 USD.
  • 1.2K
  • 10 Oct 2022
Topic Review
Brain Natriuretic Peptide
Brain natriuretic peptide (BNP), also known as B-type natriuretic peptide, is a hormone secreted by cardiomyocytes in the heart ventricles in response to stretching caused by increased ventricular blood volume. BNP is named as such because it was originally identified in extracts of pig brain. The 32-amino acid polypeptide BNP is secreted attached to a 76–amino acid N-terminal fragment in the prohormone called NT-proBNP (BNPT), which is biologically inactive. Once released, BNP binds to and activates the atrial natriuretic factor receptor NPRA, and to a lesser extent NPRB, in a fashion similar to atrial natriuretic peptide (ANP) but with 10-fold lower affinity. The biological half-life of BNP, however, is twice as long as that of ANP, and that of NT-proBNP is even longer, making these peptides better targets than ANP for diagnostic blood testing. The physiologic actions of BNP are similar to those of ANP and include decrease in systemic vascular resistance and central venous pressure as well as an increase in natriuresis. The net effect of these peptides is a decrease in blood pressure due to the decrease in systemic vascular resistance and, thus, afterload. Additionally, the actions of both BNP and ANP result in a decrease in cardiac output due to an overall decrease in central venous pressure and preload as a result of the reduction in blood volume that follows natriuresis and diuresis.
  • 1.2K
  • 28 Oct 2022
Topic Review
Respiratory Distress and PCD
Primary ciliary dyskinesia (PCD) is inherited in a predominantly autosomal recessive manner with over 45 currently identified causative genes. It is a clinically heterogeneous disorder that results in a chronic wet cough and drainage from the paranasal sinuses, chronic otitis media with hearing impairment as well as male infertility. Approximately 50% of patients have situs inversus totalis. Prior to the development of chronic oto-sino-pulmonary symptoms, neonatal respiratory distress occurs in more than 80% of patients as a result of impaired mucociliary clearance and mucus impaction causing atelectasis and lobar collapse. Diagnosis is often delayed due to overlapping symptoms with other causes of neonatal respiratory distress. A work up for PCD should be initiated in the newborn with compatible clinical features, especially those with respiratory distress, consistent radiographic findings or persistent oxygen requirement and/or organ laterality defects
  • 1.2K
  • 10 Mar 2021
Topic Review
Immobilization and Stabilization of Bacteriophages
Phages are effective at targeting and killing bacterial strains of interest and have yielded encouraging results when administered as part of a tailored treatment to severely ill patients as a last resort.  The incorporation of bacteriophages into therapeutic formulations typically involves encapsulating them within a stabilizing substance. Immobilization refers to the chemical, physio-chemical or electrostatic binding of bacteriophages to a surface. 
  • 1.2K
  • 21 May 2021
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