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Topic Review
Biography
Topic Review
Human Neuroblastoma Cell
Neuroblastoma is one of the most common childhood solid tumors and develops from neural stem cells that normally comprise the embryonic structure termed the neural crest. Human neuroblastoma cell lines have special properties as they exhibit cell growth and are induced to become mature neurons by drugs such as retinoid.
649
21 Oct 2021
Topic Review
Human Papillomavirus Infection in Penile Cancer
Penile cancer (PC) is a rare male malignant tumor, with early lymph node metastasis and poor prognosis. Human papillomavirus (HPV) plays a key role in the carcinogenesis of PC.
118
11 Dec 2023
Topic Review
Human Sirtuins
Sirtuins (SIRTs) are nicotinamide adenine dinucleotide-dependent histone deacetylases that in-corporate complex functions in the mechanisms of cell physiology. Mammals have seven distinct members of the SIRT family (SIRT1-7), which play an important role in a well-maintained net-work of metabolic pathways that control and adapt the cell to the environment, energy availabil-ity and cellular stress. Until recently, very few studies investigated the role of SIRTs in modulating viral infection and progeny. Recent studies have demonstrated that SIRT1 and SIRT2 are promis-ing antiviral targets because of their specific connection to numerous metabolic and regulatory processes affected during infection.
669
01 Mar 2021
Topic Review
Huntingtin and Other Neurodegeneration-Associated Proteins in Intracellular Pathologies
Neurodegenerative diseases are currently incurable. Numerous experimental data accumulated over the past fifty years have brought us closer to understanding the molecular and cell mechanisms responsible for their development. It is known that the basis of neurodegenerations are proteinopathies, disorders in the structure and function of various proteins that lead to their aggregation and toxic effects on cells. The most common neurodegenerative proteinopathies are amyloidosis (amyloid extracellular plaques in AD), tauopathy (various dementias), α-synucleopathy (Lowy bodies in PD), prionopathy, and TDP-43 proteinopathy (in amyotrophic lateral sclerosis (ALS)).
598
26 Dec 2022
Topic Review
Hyaluronan
Hyaluronan (HA) is a major component of the ECM that consists of repeated disaccharide units of N-acetylglucosamine and glucuronic acid. HA is synthesized as a high molecular weight molecule but is degraded into heterogeneous fragments by hyaluronidases and reactive oxygen or nitrogen species. The biological activity of HA depends on its molecular weight. HA fragments stimulate tissue inflammation and fibrosis. In contrast, high molecular weight HA suppresses these processes and maintains tissue homeostasis. This functional duality is particularly important during wound repair where HA sequentially promotes then suppresses inflammation and fibrosis. In contrast, in tumors, HA effects are often co-opted to increase growth and invasion.
1.0K
29 Nov 2021
Topic Review
Hydrogel-Forming Microneedles
Controlled drug delivery in the oral cavity poses challenges such as bacterial contamination, saliva dilution, and inactivation by salivary enzymes upon ingestion. Microneedles offer a location-specific, minimally invasive, and retentive approach. Hydrogel-forming microneedles (HFMs) have emerged for dental diagnostics and therapeutics. HFMs penetrate the stratum corneum, undergo swelling upon contact, secure attachment, and enable sustained transdermal or transmucosal drug delivery. Commonly employed polymers such as polyvinyl alcohol (PVA) and polyvinyl pyrrolidone are crosslinked with tartaric acid or its derivatives while incorporating therapeutic agents. Microneedle patches provide suture-free and painless drug delivery to keratinized or non-keratinized mucosa, facilitating site-specific treatment and patient compliance.
450
24 Aug 2023
Topic Review
Hyperinsulinaemia-Osteofragilitas
Bone fragility leading to increased risk of low energy (fragility) fractures that is independent of bone mineral density, occurring in individuals with detected and undetected hyperinsulinaemia. Patients with type 2 diabetes mellitus (T2DM) and/or cardiovascular disease (CVD), conditions of hyperinsulinaemia, have lower levels of osteocalcin and bone remodelling, and increased rates of fragility fractures. Unlike osteoporosis with lower bone mineral density (BMD), T2DM bone fragility “hyperinsulinaemia-osteofragilitas” phenotype presents with normal to increased BMD. Hyperinsulinaemia and insulin resistance positively associate with increased BMD and fragility fractures. Hyperinsulinaemia enforces glucose fuelling, which decreases NAD+-dependent antioxidant activity. This increases reactive oxygen species and mitochondrial fission, and decreases oxidative phosphorylation high-energy production capacity, required for osteoblasto/cytogenesis. Osteocytes directly mineralise and resorb bone, and inhibit mineralisation of their lacunocanalicular space via pyrophosphate. Hyperinsulinaemia decreases vitamin D availability via adipocyte sequestration, reducing dendrite connectivity, and compromising osteocyte viability. Decreased bone remodelling and micropetrosis ensues. Trapped/entombed magnesium within micropetrosis fossilisation spaces propagates magnesium deficiency (MgD), potentiating hyperinsulinaemia and decreases vitamin D transport. Vitamin D deficiency reduces osteocalcin synthesis and favours osteocyte apoptosis. Carbohydrate restriction/fasting/ketosis increases beta-oxidation, ketolysis, NAD+-dependent antioxidant activity, osteocyte viability and osteocalcin, and decreases excess insulin exposure. Osteocalcin is required for hydroxyapatite alignment, conferring bone structural integrity, decreasing fracture risk and improving metabolic/endocrine homeodynamics. Patients presenting with fracture and normal BMD should be investigated for T2DM and hyperinsulinaemia.
1.1K
09 Oct 2021
Topic Review
Hyperprogressive Disease
Hyperprogressive disease (HPD) is an adverse outcome of immunotherapy consisting in an acceleration of tumor growth, often accompanied by prompt clinical deterioration.
440
27 May 2021
Topic Review
Hyperthermia
Hyperthermia is one of the severe acute adverse effects that can be caused by the ingestion of recreational drugs, such as methcathinones. The effect of hyperthermia on neurotoxicity is currently not known. The primary aim of our study was therefore to investigate the effects of hyperthermia (40.5 °C) on the neurotoxicity of methcathinone (MC), 4-chloromethcathinone (4-CMC), and 4-methylmethcathinone (4-MMC) in SH-SY5Y cells. We found that 4-CMC and 4-MMC were cytotoxic (decrease in cellular ATP and plasma membrane damage) under both hyper- (40.5 °C) and normothermic conditions (37 °C), whereby cells were more sensitive to the toxicants at 40.5 °C. 4-CMC and 4-MMC impaired the function of the mitochondrial electron transport chain and increased mitochondrial formation of reactive oxygen species (ROS) in SH-SY5Y cells, which were accentuated under hyperthermic conditions. Hyperthermia was associated with a rapid expression of the 70 kilodalton heat shock protein (Hsp70), which partially prevented cell death after 6 h of exposure to the toxicants. After 24 h of exposure, autophagy was stimulated by the toxicants and by hyperthermia but could only partially prevent cell death. In conclusion, hyperthermic conditions increased the neurotoxic properties of methcathinones despite the stimulation of protective mechanisms. These findings may be important for the understanding of the mechanisms and clinical consequences of the neurotoxicity associated with these compounds.
763
29 Oct 2020
Topic Review
Hypoxia in Cardiovascular Diseases
Heart valve diseases are a major contributor to cardiovascular morbidity and mortality worldwide. They affect more than 13% of the population aged over 75 years old and occur when any type of the four heart valves (tricuspid, pulmonic, mitral, and aortic valves) is damaged. Calcific aortic valve disease (CAVD) is defined as a slowly progressing condition that ranges from mild valve aortic sclerosis to severe calcifying aortic valve stenosis. This progression manifests in approximately 2% of individuals over 65 years old annually.
272
20 Jul 2023
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