ABSTRACT
BACKGROUND: Adolescents and young adults (AYAs) represent a small proportion of patients with cancer. The genomic profiles of AYA patients with cancer are not well-studied, and outcomes of genome-matched therapies remain largely unknown. PATIENTS AND METHODS: We investigated differences between Japanese AYA and older adult (OA) patients in genomic alterations, therapeutic evidence levels, and genome-matched therapy usage by cancer type. We also assessed treatment outcomes. RESULTS: AYA patients accounted for 8.3% of 876 cases. Microsatellite instability-high and/or tumor mutation burden was less common in AYA patients (1.4% versus 7.7% in OA; P = 0.05). However, BRCA1 alterations were more common in AYA patients with breast cancer (27.3% versus 1.7% in OA; P = 0.01), as were MYC alterations in AYA patients with colorectal cancer (23.5% versus 5.8% in OA; P = 0.02) and sarcoma (31.3% versus 3.4% in OA; P = 0.01). Genome-matched therapy use was similar between groups, with overall survival tending to improve in both. However, in AYA patients, the small number of patients prevented statistical significance. Comprehensive genomic profiling-guided genome-matched therapy yielded encouraging results, with progression-free survival of 9.0 months in AYA versus 3.7 months in OA patients (P = 0.59). CONCLUSION: Our study suggests that tailored therapeutic approaches can benefit cancer patients regardless of age.
ABSTRACT
Streptococcus pneumoniae is an important human pathogen. Currently used conjugate vaccines are effective against invasive disease, but protection is restricted to serotypes included in the formulation, leading to serotype replacement. Furthermore, protection against non-invasive disease is reported to be considerably lower. The development of a serotype-independent vaccine is thus important and Pneumococcal surface protein A (PspA) is a promising vaccine candidate. PspA shows some diversity and can be classified in 6 clades and 3 families, with families 1 and 2 being the most frequent in clinical isolates. The ideal vaccine should thus induce protection against the two most common families of PspA. The aim of this work was to develop a liposome-based vaccine containing PspAs from family 1 and 2 and to characterize its immune response. Liposomes (LP) composed of dipalmitoylphosphatidylcholine (DPPC) and 3ß-[N-(N',N'-dimethylaminoethane)-carbamoyl]cholesterol (DC-Chol) with or without α-galactosylceramide (α-GalCer) were produced by microfluidics, encapsulating PspA from clade 1 (PspA1, family 1) and/or clade 4 (PspA4Pro, family 2) followed by spray-drying with trehalose to form nanocomposite microparticles carriers (NCMP). LP/NCMPs showed good stability and preservation of protein activity. LP/NCMPs containing PspA1 and/or PspA4Pro were used for immunization of mice targeting the lungs. High serum IgG antibody titers against both PspA1 and PspA4Pro were detected in animals immunized with LP/NCMPs containing α-GalCer, with a balance of IgG1 and IgG2a titers. IgG in sera from immunized mice bound to pneumococcal strains from different serotypes and expressing different PspA clades, indicating broad recognition. Mucosal IgG and IgA were also detected. Importantly, immunization with LP/NCMPs induced full protection against strains expressing PspAs from family 1 and 2. Furthermore, CD4+ resident memory T cells were detected in the lungs of the immunized animals that survived the challenge.
Subject(s)
Galactosylceramides , Pneumococcal Infections , Streptococcus pneumoniae , Humans , Animals , Mice , Liposomes , Powders , Pneumococcal Infections/prevention & control , Bacterial Proteins , Immunization , Pneumococcal Vaccines , Immunoglobulin G , Lung , Antibodies, Bacterial , Mice, Inbred BALB CABSTRACT
Streptococcus pneumoniae is an important human pathogen. Currently used conjugate vaccines are effective against invasive disease, but protection is restricted to serotypes included in the formulation, leading to serotype replacement. Furthermore, protection against non-invasive disease is reported to be considerably lower. The development of a serotype-independent vaccine is thus important and Pneumococcal surface protein A (PspA) is a promising vaccine candidate. PspA shows some diversity and can be classified in 6 clades and 3 families, with families 1 and 2 being the most frequent in clinical isolates. The ideal vaccine should thus induce protection against the two most common families of PspA. The aim of this work was to develop a liposome-based vaccine containing PspAs from family 1 and 2 and to characterize its immune response. Liposomes (LP) composed of dipalmitoylphosphatidylcholine (DPPC) and 3β-[N-(N′,N′-dimethylaminoethane)-carbamoyl]cholesterol (DC-Chol) with or without α-galactosylceramide (α-GalCer) were produced by microfluidics, encapsulating PspA from clade 1 (PspA1, family 1) and/or clade 4 (PspA4Pro, family 2) followed by spray-drying with trehalose to form nanocomposite microparticles carriers (NCMP). LP/NCMPs showed good stability and preservation of protein activity. LP/NCMPs containing PspA1 and/or PspA4Pro were used for immunization of mice targeting the lungs. High serum IgG antibody titers against both PspA1 and PspA4Pro were detected in animals immunized with LP/NCMPs containing α-GalCer, with a balance of IgG1 and IgG2a titers. IgG in sera from immunized mice bound to pneumococcal strains from different serotypes and expressing different PspA clades, indicating broad recognition. Mucosal IgG and IgA were also detected. Importantly, immunization with LP/NCMPs induced full protection against strains expressing PspAs from family 1 and 2. Furthermore, CD4+ resident memory T cells were detected in the lungs of the immunized animals that survived the challenge.
ABSTRACT
We performed a preliminary study of neutron resonance absorption imaging to investigate the spatial distribution of constituent elements in borosilicate glasses containing simulated high-level radioactive waste, in which elemental inhomogeneities affect the physical and chemical stabilities of the glass. Dips generated by the resonance absorptions of Rh, Pd, Na, Gd, Cs, and Sm were observed in the neutron transmission spectra of the glass samples. The spatial distributions of these elements were obtained from the neutron transmission images at the resonance energies. The distributions of Rh and Pd visualized the sedimentation of these platinum group elements. In contrast, the lanthanides (Gd and Sm) and Cs were uniformly dispersed. These results show that neutron resonance absorption imaging is a promising tool for characterizing borosilicate glasses and investigating the vitrification mechanism of high-level radioactive waste.
ABSTRACT
Shapes and shape evolution in the mass-130 region, including the Te, Xe, and Ba isotopes, have long been a focus of discussion in nuclear physics. This mass region consists of complex many-body systems that can behave in astonishingly simple and regular ways, as classified in the Casten symmetry triangle. By applying the shell model Hamiltonian proposed recently, we carry out calculations using the Hartree-Fock-Bogolyubov plus generator coordinate method, in the large model space containing the (1g_{9/2},1g_{7/2},2d_{5/2},2d_{3/2},3s_{1/2},1h_{11/2},2f_{7/2}) orbits. Based on good reproduction of the experimentally known energy levels, spectroscopic quadrupole moments, and E2 transition probabilities, we identify the quasi-SU(3) couplings across the N=50 and 82 shell gaps, which play a role in driving shape evolution and phase transition discussed in the extended Casten triangle. Specifically, we demonstrate that the quasi-SU(3) coupling mechanism in the proton partner orbits (1g_{9/2}, 2d_{5/2}) tends to drive the system to be more γ soft, and that in the neutron partner orbits (1h_{11/2}, 2f_{7/2}) are responsible for the oblate-to-prolate shape phase transition. With an emphasis on discussing spectroscopic quadrupole moments, our Letter uncovers hidden symmetries from the vast shell-model configurations and adds microscopical insights into the empirical symmetry triangle.
ABSTRACT
ß decay of proton-rich nuclei plays an important role in exploring isospin mixing. The ß decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through ß-delayed two-proton emission (ß2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P ß decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in ß-decay experiments.
ABSTRACT
OBJECTIVES: We previously reported, based on a multicenter randomized-control study, that the efficacy of intra-articular injections of hyaluronic acid (IA-HA) was not inferior to that of oral non-steroidal anti-inflammatory drugs (NSAIDs) in patients with knee osteoarthritis (OA). However, the molecular effects on the pathophysiology of knee OA remain unclear. C-terminal telopeptides of type II collagen (CTX-II) is reported to primarily originate from the interface between articular cartilage and subchondral bone, which is a site of potential remodeling in OA. We performed a predefined sub-analysis of the previous study to compare the changes of urinary CTX-II (uCTX-II) in response to IA-HA to those in response to NSAID for knee OA. DESIGN: A total of 200 knee OA patients were registered from 20 hospitals and randomized to receive IA-HA (2,700 kDa HA, 5 times at 1-week intervals) or NSAID (loxoprofen sodium, 180 mg/day) for 5 weeks. The uCTX-II levels were measured before and after treatment. RESULTS: The uCTX-II levels were significantly increased by IA-HA treatment (337.7 ± 193.8 to 370.7 ± 234.8 ng/µmol Cr) and were significantly reduced by NSAID treatment (423.2 ± 257.6 to 370.3 ± 250.9 ng/µmol Cr). The %changes of uCTX-II induced by IA-HA (11.6 ± 29.5%) and NSAID (-9.0 ± 26.7%) was significantly different (between-group difference: 20.6, 95% confidence intervals: 10.6 to 30.6). CONCLUSIONS: While both IA-HA and NSAID improved symptoms of knee OA, uCTX-II levels were increased by IA-HA and reduced by NSAIDs treatment, suggesting these treatments may improve symptoms of knee OA through different modes of action.
Subject(s)
Osteoarthritis, Knee , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Biomarkers , Collagen Type II , Humans , Hyaluronic Acid/therapeutic use , Injections, Intra-Articular , Molecular Weight , Treatment Outcome , Viscosupplements/therapeutic useABSTRACT
Lactococcus lactis has been reported unable to directly incorporate mononucleotides but instead requires their external dephosphorylation by nucleotidases to the corresponding nucleosides prior to their incorporation. Although Lactobacillus gasseri PA-3 (PA-3), a strain of lactic acid bacteria, has been found to incorporate purine mononucleotides such as adenosine 5'-monophosphate (AMP), it remains unclear whether these bacteria directly incorporate these mononucleotides or incorporate them after dephosphorylation to the corresponding nucleosides. This study evaluated whether PA-3 incorporated radioactively-labeled mononucleotides in the presence or absence of the 5'-nucleotidase inhibitor α,ß-methylene ADP (APCP). PA-3 took up 14C-AMP in the presence of APCP, as well as incorporating 32P-AMP. Furthermore, radioactivity was detected in the RNA/DNA of bacterial cells cultured in the presence of 32P-AMP. Taken together, these findings indicated that PA-3 incorporated purine mononucleotides directly rather than after their dephosphorylation to purine nucleosides and that PA-3 utilizes these purine mononucleotides in the synthesis of RNA and DNA. Although additional studies are required to identify purine mononucleotide transporters in PA-3, this study is the first to show that some lactic acid bacteria directly incorporate purine mononucleotides and use them for growth.
Subject(s)
Lactobacillus gasseri , Adenosine Monophosphate/metabolism , Lactobacillus gasseri/metabolism , Nucleotidases/metabolism , Purine Nucleosides/metabolismABSTRACT
This study investigated risk factors for osteonecrosis involving multiple joints (MJON) among glucocorticoid-treated patients. The best predictor of MJON was cumulative oral glucocorticoid dose. Risk of MJON was 12-fold higher in patients who had a second risk factor for osteonecrosis. Further research is needed into strategies for prevention of MJON. INTRODUCTION: Osteonecrosis (ON) is a debilitating musculoskeletal condition in which bone cell death can lead to mechanical failure. When multiple joints are affected, pain and disability are compounded. Glucocorticoid treatment is one of the most common predisposing factors for ON. This study investigated risk factors for ON involving multiple joints (MJON) among glucocorticoid-treated patients. METHODS: Fifty-five adults with glucocorticoid-induced ON were prospectively enrolled. MJON was defined as ON in ≥ three joints. Route, dose, duration, and timing of glucocorticoid treatment were assessed. RESULTS: Mean age of enrolled subjects was 44 years, 58% were women. Half had underlying conditions associated with increased ON risk: systemic lupus erythematosus (29%), acute lymphoblastic leukemia (11%), HIV (9%), and alcohol use (4%). Mean daily oral dose of glucocorticoids was 29 mg. Average cumulative oral dose was 30 g over 5 years. The best predictor of MJON was cumulative oral glucocorticoid dose. For each increase of 1,000 mg, risk of MJON increased by 3.2% (95% CI 1.03, 1.67). Glucocorticoid exposure in the first 6 months of therapy, peak dose (oral or IV), and mean daily dose did not independently increase risk of MJON. The risk of MJON was 12-fold in patients who had a second risk factor (95% CI 3.2, 44.4). CONCLUSIONS: Among patients with glucocorticoid-induced ON, cumulative oral dose was the best predictor of multi-joint disease; initial doses of IV and oral glucocorticoids did not independently increase risk. Further research is needed to better define optimal strategies for prevention and treatment of MJON.
Subject(s)
Joint Diseases , Lupus Erythematosus, Systemic , Osteonecrosis , Adult , Female , Glucocorticoids/adverse effects , Humans , Osteonecrosis/chemically induced , Osteonecrosis/epidemiology , Risk FactorsABSTRACT
Dietary purine restrictions are recommended for patients with hyperuricemia and gout. While measuring the purine contents of various foods in our laboratory using high-performance liquid chromatography (HPLC), we observed and reported changes in purine composition. In this study, we measured the total purine content and free purine of raw anchovies as well as after fermentation, using two methods by HPLC. Method 1 involved acid hydrolysis of all purines, such as nucleic acids and nucleotides, to form four corresponding purine bases. Method 2, which is a non-hydrolysis method, is used to measure the amount of free purines (nucleotide, nucleoside, purine base). As a result of method 1, after fermentation, adenine-related and hypoxanthine-related purines and the total purine levels decreased significantly. Regardless of being raw or fermented, each anchovy contained mainly hypoxanthine- and guanine-related purines. Among the hypoxanthine-related purines, the results of method 2 revealed that the raw anchovies contained a lot of inosine monophosphate (IMP), while after fermentation contained more inosine. In guanine-related and adenine-related purines, those nucleotides decreased by fermentation and nucleosides and bases increased. Measurements of free purines revealed that those reductions after fermentation observed in method 1 were derived from decreased nucleotides. These results indicate that purines are affected by the fermentation bacteria and period.
Subject(s)
Chromatography, High Pressure Liquid , Fishes , Food Analysis , Purine Nucleosides/analysis , Purine Nucleotides/analysis , Spectrophotometry, Ultraviolet , Animals , Fermentation , Seafood/analysisABSTRACT
ß-delayed one-proton emissions of ^{22}Si, the lightest nucleus with an isospin projection T_{z}=-3, are studied with a silicon array surrounded by high-purity germanium detectors. Properties of ß-decay branches and the reduced transition probabilities for the transitions to the low-lying states of ^{22}Al are determined. Compared to the mirror ß decay of ^{22}O, the largest value of mirror asymmetry in low-lying states by far, with δ=209(96), is found in the transition to the first 1^{+} excited state. Shell-model calculation with isospin-nonconserving forces, including the T=1, J=2, 3 interaction related to the s_{1/2} orbit that introduces explicitly the isospin-symmetry breaking force and describes the loosely bound nature of the wave functions of the s_{1/2} orbit, can reproduce the observed data well and consistently explain the observation that a large δ value occurs for the first but not for the second 1^{+} excited state of ^{22}Al. Our results, while supporting the proton-halo structure in ^{22}Al, might provide another means to identify halo nuclei.
ABSTRACT
Although most lactic acid bacteria do not directly incorporate purine nucleotides, the strain Lactobacillus gasseri PA-3 was found to incorporate purine mononucleotides. To determine whether the direct uptake of purine mononucleotides is dependent on the species or strain of lactic acid bacteria, incorporation of purine mononucleotides was assessed in L. gasseri, Lactcoccus lactis sbsp. lactis, Streptococcus thermophilus and other species of lactic acid bacteria. Each bacterial strain was incubated with 32P-AMP or 14C-adenosine and the incorporation of each purine was evaluated by measuring their radioactivity. All investigated strains of L. gasseri incorporated 32P-AMP, whereas strains of S. thermophilus and most strains of L. lactis did not. Incorporation of 32P-AMP into strains of Pediococcus was dependent on the strain or species of that genus of bacteria. All investigated strains, except for one strain of L. gasseri, incorporated 14C-adenosine, with S. thermophilus, L. lactis and Pediococcus generally displaying greater incorporation of 14C-adenosine than L. gasseri. Although most lactic acid bacteria such as S. thermophiles and L. lactis do not incorporate purine mononucleotides, some species such as L. gasseri directly incorporate purine mononucleotides. These findings indicate that the preferential incorporation of purine mononucleotides or nucleosides by lactic acid bacteria is dependent on the species or strain.
Subject(s)
Adenosine Monophosphate/metabolism , Adenosine/metabolism , Bacteria/metabolism , Lactic Acid/biosynthesis , Biological Transport , Species SpecificityABSTRACT
A new RIKEN 28-GHz superconducting electron cyclotron resonance ion source (SC-ECRIS) has been installed for the superconducting RIKEN linear accelerator (SRILAC). The new SC-ECRIS control system mainly consists of programmable logic controllers (PLCs) embedded with the Experimental Physics and Industrial Control System. To improve the reliability as compared with previous control systems, two types of PLC central processing units, sequential and Linux, have been installed in the same unit. Past experience has shown that new types of designs that can rapidly respond to system scalability are key. By connecting PLC stations using star-topology field buses, their rapid and cost-effective response to system changes is realized for the new devices. Furthermore, a unique data acquisition system employing a 920-MHz-band radio was developed to measure analog data such as the temperature at the high-voltage stage.
Subject(s)
Adenocarcinoma of Lung/complications , Amino Acyl-tRNA Synthetases/immunology , Antibodies/blood , Lung Diseases, Interstitial/etiology , Lung Neoplasms/complications , Nivolumab/adverse effects , Polymyositis/chemically induced , Adenocarcinoma of Lung/diagnosis , Adenocarcinoma of Lung/drug therapy , Aged, 80 and over , Antineoplastic Agents, Immunological/adverse effects , Antineoplastic Agents, Immunological/therapeutic use , Electromyography , Humans , Lung Diseases, Interstitial/diagnosis , Lung Neoplasms/diagnosis , Lung Neoplasms/drug therapy , Magnetic Resonance Imaging , Male , Nivolumab/therapeutic use , Polymyositis/complications , Polymyositis/immunology , Tomography, X-Ray ComputedABSTRACT
External fixators are an effective treatment option for comminuted or unstable phalangeal fractures. We developed a new linked-wire type of external fixator (the Ichi-Fixator) for finger phalangeal fractures, which enables fine adjustment of the fixation under fluoroscopy guidance either in a static way or with distraction through small screws inside the fixator. This technique was designed to improve on the stability and rigidity of conventional percutaneous Kirchner wire fixation. We assessed the effectiveness of the fixator through 12 cases of open or percutaneous fixation in comminuted or unstable phalangeal fractures. All patients were examined for postoperative complications, functional recovery, pain on visual analog scale (VAS), and the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) score at the final follow-up visit. Patients could perform all routine activities with normal grip strength and a full range of hand motion without pain after treatment. This treatment, which reduces the postoperative discomfort and may allow an immediate return to work, will clearly boost patient satisfaction. Linked-wire type external fixation enhances the security of fixation, facilitates postoperative mobilization, and may allow an immediate return to work.
Subject(s)
External Fixators , Finger Phalanges/surgery , Fractures, Comminuted/surgery , Adolescent , Adult , Disability Evaluation , Equipment Design , Female , Finger Phalanges/injuries , Humans , Male , Middle Aged , Prospective Studies , Recovery of Function , Visual Analog Scale , Young AdultSubject(s)
Azathioprine/administration & dosage , B-Lymphocytes/drug effects , Immunosuppressive Agents/administration & dosage , Lupus Erythematosus, Systemic/drug therapy , Prenatal Exposure Delayed Effects/immunology , Adult , Azathioprine/adverse effects , Cell Proliferation/drug effects , Female , Humans , Immunosuppressive Agents/adverse effects , Infant, Newborn , Pregnancy , Pregnancy Complications/drug therapy , Pregnancy OutcomeABSTRACT
In this study, we investigated the alterations in the purine composition of swordfish prepared using a traditional Japanese processing method of soaking in sake lees. These alterations are the byproducts of the yeast fermentation of rice-koji and are renowned for enhancing the umami nature of food. Using a conventional assay method for hydrolyzing all of the purines into four bases and our developed method for simultaneously analyzing purines, we observed the alterations in four purine bases in the soaked sake lees and swordfish. The findings showed that the total purine content, and hypoxanthine-related and guanine-related purines in swordfish decreased after soaking in sake lees. We also analyzed the free purine composition and showed that the ratio of IMP in swordfish was decreased by soaking, while that of inosine in sake lees was increased by soaking swordfish in it.
Subject(s)
Cyprinodontiformes , Food Handling , Purines/analysis , Wine , Animals , Fermentation , Food Analysis , Guanine/analysis , Humans , Hypoxanthine/analysis , Inosine/analysisABSTRACT
Ribonucleotide flavor enhancers such as inosine monophosphate (IMP) and guanosine monophosphate (GMP) provide umami taste, similarly to glutamine. Japanese cuisine frequently uses soup stocks containing these nucleotides to enhance umami. We quantified 18 types of purines (nucleotides, nucleosides, and purine bases) in three soup stocks (chicken, consommé, and dried bonito soup). IMP was the most abundant purine in all umami soup stocks, followed by hypoxanthine, inosine, and GMP. The IMP content of dried bonito soup was the highest of the three soup stocks. We also evaluated the effects of these purines on extracellular and intracellular purine metabolism in HepG2 cells after adding each umami soup stock to the cells. An increase in inosine and hypoxanthine was evident 1 h and 4 h after soup stock addition, and a low amount of xanthine and guanosine was observed in the extracellular medium. The addition of chicken soup stock resulted in increased intracellular and extracellular levels of uric acid and guanosine. Purine metabolism may be affected by ingredients present in soups.
Subject(s)
Food , Purines/analysis , Purines/metabolism , Animals , Chromatography, High Pressure Liquid/methods , Food Ingredients/analysis , Guanosine/metabolism , Hep G2 Cells , Humans , Hypoxanthine/metabolism , Inosine/metabolism , Uric Acid/metabolism , Xanthine/metabolismABSTRACT
Osteoclasts are multinucleated giant cells differentiated from monocyte-macrophage-lineage cells under stimulation of receptor activator of nuclear factor κ-B (RANK) ligand (RANKL) produced by osteoblasts and osteocytes. Although it has been reported that nitric oxide (NO) and reactive oxygen species (ROS) are involved in this process, the mechanism by which these labile molecules promote osteoclast differentiation are not fully understood. In this study, we investigated the formation and function of 8-nitro-cGMP, a downstream molecule of NO and ROS, in the process of osteoclast differentiation in vitro. 8-Nitro-cGMP was detected in mouse bone marrow macrophages and osteoclasts differentiated from macrophages in the presence of RANKL. Inhibition of NO synthase suppressed the formation of 8-nitro-cGMP as well as RANKL-induced osteoclast differentiation from macrophages. On the other hand, RANKL-induced osteoclast differentiation was promoted by addition of 8-nitro-cGMP to the cultures. In addition, 8-nitro-cGMP enhanced the mRNA expression of RANK, the receptor for RANKL. However, 8-bromo-cGMP, a membrane-permeable derivative of cGMP, did not have an effect on either RANKL-induced osteoclast differentiation or expression of the RANK gene. These results suggest that 8-nitro-cGMP is a novel positive regulator of osteoclast differentiation, which might help to explain the roles of NO and ROS in osteoclast differentiation.
Subject(s)
Cell Differentiation , Cyclic GMP/analogs & derivatives , Osteoclasts/physiology , RANK Ligand/metabolism , Animals , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cells, Cultured , Cyclic GMP/metabolism , Cyclic GMP/pharmacology , Cyclic GMP-Dependent Protein Kinases/metabolism , Enzyme Inhibitors/pharmacology , Gene Expression Regulation , Macrophages/cytology , Male , Mice, Inbred Strains , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide/metabolism , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/metabolism , Osteoclasts/cytology , Osteoclasts/drug effects , RANK Ligand/pharmacology , Receptor Activator of Nuclear Factor-kappa B/geneticsABSTRACT
In this opinion piece, we discuss how to place evolution in the context of origin-of-life research. Our discussion starts with a popular definition: 'life is a self-sustained chemical system capable of undergoing Darwinian evolution'. According to this definition, the origin of life is the same as the origin of evolution: evolution is the 'end' of the origin of life. This perspective, however, has a limitation, in that the ability of evolution in and of itself is insufficient to explain the origin of life as we know it, as indicated by Spiegelman's and Lincoln and Joyce's experiments. This limitation provokes a crucial question: What conditions are required for replicating systems to evolve into life? From this perspective, the origin of life includes the emergence of life through evolution: evolution is a 'means' of the origin of life. After reviewing Eigen's pioneering work on this question, we mention our ongoing work suggesting that a key condition might be conflicting multi-level evolution. Taken together, there are thus two questions regarding the origin of life: how evolution gets started, and how evolution produces life. Evolution is, therefore, at the centre of the origin of life, where the two lines of enquiry must meet.This article is part of the themed issue 'Reconceptualizing the origins of life'.