The noncanonical NFκB signaling pathway mediates the biological functions of diverse cell survival, growth, maturation, and differentiation factors that are important for the development and maintenance of hematopoietic cells and immune organs. Its dysregulation is associated with a number of immune pathologies and malignancies. Originally described as the signaling pathway that controls the NFκB family member RelB, we now know that noncanonical signaling also controls NFκB RelA and cRel. Here, we aim to clarify our understanding of the molecular network that mediates noncanonical NFκB signaling and review the human diseases that result from a deficient or hyper-active noncanonical NFκB pathway. It turns out that dysregulation of RelA and cRel, not RelB, is often implicated in mediating the resulting pathology. This article is categorized under: Immune System Diseases > Molecular and Cellular Physiology Cancer > Molecular and Cellular Physiology Immune System Diseases > Stem Cells and Development.

Proposed effects of melatonin on anterior segment cells. Melatonin is a potent melanogenesis suppressor acting by inhibiting α-MSH effects. As a result, melanin-containing granules aggregate around the nucleus. Melatonin is a potent antioxidant capable of scavenging ROS/RNS generated by UV radiation (UV-R). Melatonin and its analogs bind to putative MT3 receptors in the ciliary body and significantly downregulate β2-adrenergic receptor expression while upregulating the α2A receptor. Through this action, adenylyl cyclase (AC) is downregulated, which leads to a decrease in AH production and IOP. Additionally, α2-adrenergic receptor agonism increases uveoscleral AH outflow (not shown).

Computational modeling has well-established utility in the study of cardiovascular hemodynamics, with applications in medical research and, increasingly, in clinical settings to improve the diagnosis and treatment of cardiovascular diseases. Most cardiovascular models developed to date have been of the adult circulatory system; however, the perinatal period is unique as cardiovascular physiology undergoes drastic changes from the fetal circulation, during the birth transition, and into neonatal life. There may also be further complications in this period: for example, preterm birth (defined as birth before completed weeks of gestation) carries risks of short-term cardiovascular instability and is associated with increased lifetime cardiovascular risk. Here, we review computational models of the cardiovascular system in early life, their applications to date and potential improvements and enhancements of these models. We propose a roadmap for developing an open-source cardiovascular model that spans the fetal, perinatal, and postnatal periods. This article is categorized under: Cardiovascular Diseases > Computational Models Cardiovascular Diseases > Biomedical Engineering Congenital Diseases > Computational Models.

Cyclooxygenase-2 (COX-2) is a key aspect of the physiology and pathogenesis of various cancer types. Overexpression of this enzyme is responsible for the elevated prostaglandin production and characteristic feature of breast cancer. Inhibition of COX-2 derived prostanoids facilitates anti-inflammatory, analgesic, and antipyretic effects of non-steroid anti-inflammation drugs. The overexpression of COX-2 is associated with inflammation, pain, and fever. The present study provides the updated relevant literature describing the role of well-characterized isoforms of cyclooxygenase with particular emphasis on COX-2, mechanism of action, the effect of the drug, combinatorial drugs, and microarray-based differential expression analysis and network analysis. We have discussed the currently used combinatorial treatments and their challenges in breast cancer. This article is categorized under: Cancer > Computational Models Cancer > Molecular and Cellular Physiology.

The mammalian acrosome is a secretory vesicle attached to the sperm nucleus whose fusion with the overlying plasma membrane is required to achieve fertilization. Acrosome biogenesis starts during meiosis, but it lasts through the entire process of haploid cell differentiation (spermiogenesis). Acrosome biogenesis is a stepwise process that involves membrane traffic from the Golgi apparatus, but it also seems that the lysosome/endosome system participates in this process. Defective sperm head morphology is accompanied by defective acrosome shape and function, and patients with these characteristics are infertile or subfertile. The most extreme case of acrosome biogenesis failure is globozoospermia syndrome, which is primarily characterized by the presence of round-headed spermatozoa without acrosomes with cytoskeleton defects around the nucleus and infertility. Several genes participating in acrosome biogenesis have been uncovered using genetic deletions in mice, but only a few of them have been found to be deleted or modified in patients with globozoospermia. Understanding acrosome biogenesis is crucial to uncovering the molecular basis of male infertility and developing new diagnostic tools and assisted reproductive technologies that may help infertile patients through more effective treatment techniques. This article is categorized under: Reproductive System Diseases > Environmental Factors Infectious Diseases > Stem Cells and Development Reproductive System Diseases > Molecular and Cellular Physiology.

Male germ cells undergo an extreme but fascinating process of chromatin remodeling that begins in the testis during the last phase of spermatogenesis and continues through epididymal sperm maturation. Most of the histones are replaced by small proteins named protamines, whose high basicity leads to a tight genomic compaction. This process is epigenetically regulated at many levels, not only by posttranslational modifications, but also by readers, writers, and erasers, in a context of a highly coordinated postmeiotic gene expression program. Protamines are key proteins for acquiring this highly specialized chromatin conformation, needed for sperm functionality. Interestingly, and contrary to what could be inferred from its very specific DNA-packaging function across protamine-containing species, human sperm chromatin contains a wide spectrum of protamine proteoforms, including truncated and posttranslationally modified proteoforms. The generation of protamine knock-out models revealed not only chromatin compaction defects, but also collateral sperm alterations contributing to infertile phenotypes, evidencing the importance of sperm chromatin protamination toward the generation of a new individual. The unique features of sperm chromatin have motivated its study, applying from conventional to the most ground-breaking techniques to disentangle its peculiarities and the cellular mechanisms governing its successful conferment, especially relevant from the protein point of view due to the important epigenetic role of sperm nuclear proteins. Gathering and contextualizing the most striking discoveries will provide a global understanding of the importance and complexity of achieving a proper chromatin compaction and exploring its implications on postfertilization events and beyond. This article is categorized under: Reproductive System Diseases > Genetics/Genomics/Epigenetics Reproductive System Diseases > Molecular and Cellular Physiology.

Extracellular vesicles (EVs) released by regenerative cells such as mesenchymal stem cells are effective facilitators of healing, therapy, and repair. Conversely, EVs released from infected and/or diseased cells could be useful as markers in the detection and diagnosis of disease conditions such as cancer at their earliest most detectable, and treatable stage. A very important type of EVs, termed exosomes offer a hypothetical new paradigm in disease detection, diagnosis, and treatment. A broad range of exosome-based biomedical and therapeutic applications are now being evaluated in recent clinical trials. Exosomes are found in virtually all bodily fluids and cells and are capable of crossing tight junctions and toughly regulated boundaries such as the blood-brain barrier. Exosomes' expedition ends when they are taken up by bystander cells which corroborates the fact that they are conduits for cells releasing them. Exosomes released by diseased cells have been associated with cell-to-cell progression of diseases like viral disease, neurodegeneration, and certain cancers. Due to high discrimination in most disease conditions, exosome uptake is usually cell-specific. Lots of research evidence have revealed that infusion of exosomes derived from regenerative cells such as stem cells could impede the development of certain infections and age-related diseases by activating self-repair machinery through RNA, DNA, protein, and lipid transfer between cells in patients. They have also been demonstrated in the restoration of the circulating population of exosomes in tissues and the fluid of recipients. The first human clinical trials of exosome therapies are now underway, establishing the future of regenerative exosome in regenerative medicine. This article is categorized under: Cancer > Stem Cells and Development Immune System Diseases > Stem Cells and Development Immune System Diseases > Molecular and Cellular Physiology.

Ceftazidime/avibactam (CAZ/AVI), a combination of ceftazidime and a novel β-lactamase inhibitor (avibactam) that has been approved by the U.S. Food and Drug Administration, the European Union, and the National Regulatory Administration in China. CAZ/AVI is used mainly to treat complicated urinary tract infections and complicated intra-abdominal infections in adults, as well as to treat patients infected with Carbapenem-resistant Enterobacteriaceae (CRE) susceptible to CAZ/AVI. However, increased clinical application of CAZ/AVI has resulted in the development of resistant strains. Mechanisms of resistance in most of these strains have been attributed to blaKPC mutations, which lead to amino acid substitutions in β-lactamase and changes in gene expression. Resistance to CAZ/AVI is also associated with reduced expression and loss of outer membrane proteins or overexpression of efflux pumps. In this review, the prevalence of CAZ/AVI-resistance bacteria, resistance mechanisms, and selection of detection methods of CAZ/AVI are demonstrated, aiming to provide scientific evidence for the clinical prevention and treatment of CAZ/AVI resistant strains, and provide guidance for the development of new drugs. This article is categorized under: Infectious Diseases > Molecular and Cellular Physiology.