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Topic Review
The Eclectic Nature of Glioma-Infiltrating Macrophages and Microglia
Glioblastomas (GBMs) are complex ecosystems composed of highly multifaceted tumor and myeloid cells capable of responding to different environmental pressures, including therapies. Recent studies have uncovered the diverse phenotypical identities of brain-populating myeloid cells. Differences in the immune proportions and phenotypes within tumors seem to be dictated by molecular features of glioma cells. Furthermore, increasing evidence underscores the significance of interactions between myeloid cells and glioma cells that allow them to evolve in a synergistic fashion to sustain tumor growth.
  • 559
  • 21 Jan 2022
Topic Review
The Duration of Menstrual Blood Loss
The duration of bleeding is not necessarily linked to the amount of loss but may be influenced by age, ethnicity, habitus, region and altitude of residence, dieting and stress. The onset of bleeding has been linked to declining steroid production by the corpus luteum. There remains considerable controversy around the extent of endometrial shedding at menstruation. This is likely to vary within and between women. The significance of a change from previous patterns, very short or prolonged bleeding, days of light loss or spotting before or after days of bleeding, or of bleed-free days that punctuate flow, remain poorly understood.
  • 219
  • 02 Aug 2023
Topic Review
The Dual Role of Reactive Oxygen Species
The phrase “reactive oxygen species” (ROS) is commonly used to describe the highly reactive free radicals and molecules originating from molecular oxygen. This so-called bi-radical state of oxygen explains its reactivity: one of its electrons can be paired with an external electron with an antiparallel spin, resulting in the production of the highly reactive superoxide radical (O2·−). Since the superoxide radical is weakly basic and highly soluble in water at physiological pH, cellular membranes are relatively impermeable to it. However, O2·− can be converted into membrane-permeable H2O2 by superoxide dismutase (SOD) or protonated to hydroperoxyl radicals (HOO·). Furthermore, O2·− reacts with H2O2 through the Haber–Weiss reaction using iron catalysis, resulting in the formation of highly reactive and cytotoxic hydroxyl radicals (HO·). Furthermore, during the hydroperoxide and polyunsaturated fatty acid metabolism, other types of ROS, namely the peroxyl (ROO·) and alkoxyl (RO·) radicals, are formed as intermediates. On the one hand, high amounts of ROS may damage biomolecules due to their high reactivity. On the other hand—at strictly regulated levels—ROS are essential to maintaining the redox homeostasis of the cells, and they are engaged in many cellular signalling pathways, so their total elimination by the antioxidant system is not expedient.
  • 957
  • 13 May 2022
Topic Review
The Dual Nature of Amaranth
The beneficial health-promoting properties of plants have been known to mankind for generations. Preparations from them are used to create recipes for dietary supplements, functional food, and medicinal products. Recently, amaranth has become an area of increasing scientific and industrial interest. This is due to its valuable biological properties, rich phytochemical composition, and wide pharmacological activity. Amaranth is a pseudo-cereal crop with a dual character, combining the features of food and health-promoting product. 
  • 644
  • 24 Mar 2022
Topic Review
The Double Homeobox Gene
The double homeobox (Dux) gene, encoding a double homeobox transcription factor, is one of the key drivers of totipotency in mice. Recent studies showed Dux was temporally expressed at the 2-cell stage and acted as a transcriptional activator during zygotic genome activation (ZGA) in embryos. A similar activation occurs in mouse embryonic stem cells, giving rise to 2-cell-like cells (2CLCs). Though the molecular mechanism underlying this expanded 2CLC potency caused by Dux activation has been partially revealed, the regulation mechanisms controlling Dux expression remain elusive.
  • 716
  • 17 Feb 2022
Topic Review Video Peer Reviewed
The Domestication of Humans
The domestication of humans is not an issue of domesticity but of the effects of the domestication syndrome on a hominin species and its genome. These effects are well expressed in the ‘anatomically modern humans’, in their physiology, behavior, genetic defects, neuropathology, and distinctive neoteny. The physiological differences between modern (gracile) humans and their ancestors, robust Homo sapiens types, are all accounted for by the domestication syndrome. From deductions we can draw about early human behavior, it appears that modifications are attributable to the same cause. The domestication hypothesis ascribes the initiation of the changes to selective breeding introduced by the consistent selection of neotenous features. That would trigger genetic pleiotropy, causing the changes that are observed.
  • 644
  • 31 Jul 2023
Topic Review
The Dog–Owner Relationship
The Cat/Dog–Owner Relationship Scale (C/DORS) is a questionnaire aimed to assess specific aspects of the pet–owner relationship. While the entire scale can be administered to both dog and cat owners, its validity and reliability have never been tested on dogs. Furthermore, validity and reliability of a scale may change depending on the respondents’ language and cultural background. Since the C/DORS was developed in English, we aimed to translate it into Italian and assess its validity and reliability on a sample of Italian dog owners. The response scale was modified to improve the variability of the owners’ responses. Overall, validity and reliability were good. The scale had the same three-factor structure (Perceived Emotional Closeness = PEC, Pet–Owner Interactions = POI, Perceived Costs = PC) reported for the original English version, although some items were removed because they did not fit the statistical model. The PEC subscale had the highest correlations with the subscales of the Lexington Attachment to Pets Scale. Finally, being a student owner was associated with higher PEC and POI scores. Conversely, owning a dog with behavioural problems was associated with lower PEC and higher PC. Owners whose dogs lived outdoors reported lower POI. Pet dog owners reported higher PEC than AAI dog owners.
  • 1.8K
  • 17 Aug 2021
Topic Review
The DNA Alkyltransferase Family of DNA Repair Proteins
DNA alkyltransferase and alkyltransferase-like family proteins are responsible for the repair of highly mutagenic and cytotoxic O6-alkylguanine and O4-alkylthymine bases in DNA. Their mechanism involves binding to the damaged DNA and flipping the base out of the DNA helix into the active site pocket in the protein. Alkyltransferases then directly and irreversibly transfer the alkyl group from the base to the active site cysteine residue. In contrast, alkyltransferase-like proteins recruit nucleotide excision repair components for O6-alkylguanine elimination. One or more of these proteins are found in all kingdoms of life, and where this has been determined, their overall DNA repair mechanism is strictly conserved between organisms.
  • 381
  • 19 Jan 2024
Topic Review
The Divergent Pluripotent in Mouse and Human Cells
Pluripotent stem cells (PSCs), which can self-renew and give rise to all cell types in all three germ layers, have great potential in regenerative medicine. Studies have shown that PSCs can have three distinct but interrelated pluripotent states: naive, formative, and primed. The PSCs of each state are derived from different stages of the early developing embryo and can be maintained in culture by different molecular mechanisms.
  • 382
  • 02 Sep 2022
Topic Review
The Disease-Inducing Potential of HERV-K
HERV-K (HML-2), the most recently active endogenous retrovirus group in humans, is transcribed during normal human embryogenesis, starting from the eight-cell stage and continuing through the emergence of epiblast cells in preimplantation blastocysts. These proviral RNAs produce viral-like particles and gag proteins in human blastocysts, indicating the presence of retroviral products during early human development. Additionally, the envelope protein of HERV-K (HML-2) from specific loci in chromosomes 12 and 19 is highly expressed on the cell membrane of human pluripotent stem cells (hPSCs). 
  • 244
  • 09 Oct 2023
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