End of Semester Exam ( Metabolism, Endocrinology, Neuro and Cancer modules Flashcards
Insulin treatment is appropriate for type I but not type II diabetic patients because
Type II diabetics produce sufficient levels of insulin
Type I diabetes is an autoimmune condition where the body cannot produce insulin due to the destruction of insulin-producing beta cells in the pancreas. Thus, insulin treatment is required for survival. In contrast, most Type II diabetic patients can produce insulin, but their bodies are resistant to it, meaning insulin treatment may not be necessary, especially early on. Instead, Type II diabetes is often managed with lifestyle changes, oral medications, or other non-insulin therapies.
Surgical removal of the ovaries is likely to result in the following changes to endocrine hormones
Reduced levels of inhibins
The ovaries produce several hormones, including inhibins, estrogen (such as estradiol), and progesterone. Surgical removal of the ovaries leads to a decrease in these hormones, including inhibins. Inhibins are important in regulating the release of follicle-stimulating hormone (FSH), so their reduction can also cause elevated levels of FSH.
The pathogenesis of dyslipidaemia involves
Exchange of cholesterol esters between low- and high-density lipoproteins
Dyslipidaemia involves abnormalities in lipid metabolism, often leading to elevated levels of low-density lipoproteins (LDL) and/or triglycerides and decreased levels of high-density lipoproteins (HDL). One key aspect of dyslipidaemia pathogenesis is the exchange of cholesterol esters between LDL and HDL, mediated by the enzyme cholesteryl ester transfer protein (CETP). This process can contribute to an imbalance of lipoproteins, particularly increasing LDL levels and reducing HDL, which are commonly observed in dyslipidaemia.
what signals is orexigenic
Ghrelin
Ghrelin is known as an orexigenic signal, meaning it stimulates appetite and food intake. It is produced in the stomach and signals the brain to promote hunger. In contrast, the other options are considered anorexigenic signals (they reduce appetite):
what is an example of a oncogenic driver
EGFR (Epidermal Growth Factor Receptor)
EGFR (Epidermal Growth Factor Receptor) is a well-known oncogenic driver, meaning it can contribute to the initiation and progression of cancer when mutated or overexpressed. Oncogenic drivers are genes whose altered function directly contributes to tumorigenesis. Mutations in EGFR can lead to increased cell proliferation and survival, making it a target for cancer therapies, especially in cancers like non-small cell lung cancer.
what is a rare cancer example
Adenoid Cystic Carcinoma
what is a tumour drug resistance mechanism
Constitutive signalling activation
Constitutive signalling activation refers to the continuous activation of cellular signaling pathways, often due to mutations in growth factor receptors or downstream signaling proteins. This mechanism can make cancer cells less responsive to drugs that target these pathways, contributing to drug resistance.
what BEST DESCRIBES the mechanism by which PEGylated liposomal doxorubicin accumulates in tumours following systemic administration
Passive tumour targeting owing to its long circulation time
PEGylated liposomal doxorubicin accumulates in tumors primarily through a mechanism known as the Enhanced Permeability and Retention (EPR) effect, which is a form of passive targeting. The PEGylation increases the drug’s circulation time, allowing it to remain in the bloodstream longer. Tumors have leaky vasculature and poor lymphatic drainage, which allows the drug to passively accumulate in the tumor tissue.
in tumour-bearing mice what occurs in loss of neuromuscular integrity and lean mass loss
Loss of neuromuscular integrity precedes lean mass loss in tumour-bearing mice
In cancer cachexia, a complex syndrome associated with severe muscle wasting, studies in animal models (such as tumor-bearing mice) have shown that neuromuscular integrity is compromised before the actual loss of lean body mass. This suggests that changes at the neuromuscular junction and nerve-muscle connectivity contribute to muscle wasting in cachexia.
Neuronal death signalling in neurodegenerative diseases can be induced by
TNF receptors, reactive oxygen species, mitochondrial dysfunction and protein aggregates
Neuronal death signaling in neurodegenerative diseases is often triggered by factors like TNF receptors, which activate inflammatory and apoptotic pathways; reactive oxygen species (ROS), which cause oxidative damage; mitochondrial dysfunction, leading to energy deficits and cell death signaling; and protein aggregates, such as amyloid plaques and tau tangles in Alzheimer’s disease or alpha-synuclein in Parkinson’s disease, which disrupt cellular homeostasis. These mechanisms contribute directly to neuronal death in neurodegenerative conditions.
Which family of signaling molecules is involved in regulating the induction of both apoptosis and autophagy
Bcl-2 family
The Bcl-2 family of proteins plays a key role in regulating both apoptosis (programmed cell death) and autophagy (a process of cellular degradation and recycling). These proteins are involved in controlling mitochondrial integrity and can either promote cell survival (anti-apoptotic members like Bcl-2) or induce cell death (pro-apoptotic members like Bax, Bak). Additionally, some Bcl-2 family proteins have been shown to influence autophagy, thus bridging the regulation of both processes.
What is the second most prevalent form of dementia?
Which pathway is associated with decreased dopamine function in schizophrenia
mesocortical
In schizophrenia, decreased dopamine function is most notably associated with the mesocortical pathway. This pathway, which connects the ventral tegmental area (VTA) to the prefrontal cortex, is involved in cognitive and executive functions. Dysfunction in this pathway, including reduced dopamine activity, is thought to contribute to the cognitive deficits and negative symptoms (such as lack of motivation and emotional blunting) seen in schizophrenia.
Which anatomical subregion of the striatum is thought to control goal-drected behaviour in rodents?
Dorsomedial
In rodents, the dorsomedial subregion of the striatum is thought to be critically involved in goal-directed behavior. It plays a key role in the planning and execution of actions driven by goals, particularly in tasks that require flexibility and decision-making based on rewards or outcomes. This area is closely linked to the prefrontal cortex and is associated with cognitive control and higher-order decision-making processes.
Which of the following factors does NOT affect vitamin D synthesis in the skin?
UVA exposure
