Activation and Function of NLRP3 Inflammasome in Bone and Joint-Related Diseases

Inflammation is a pivotal response to a variety of stimuli, and inflammatory molecules such as cytokines have central roles in the pathogenesis of various diseases, including bone and joint diseases. Proinflammatory cytokines are mainly produced by immune cells and mediate inflammatory and innate immune responses. Additionally, proinflammatory cytokines accelerate bone resorption and cartilage destruction, resulting in the destruction of bone and joint tissues. Thus, proinflammatory cytokines are involved in regulating the pathogenesis of bone and joint diseases. Interleukin (IL)-1 is a representative inflammatory cytokine that strongly promotes bone and cartilage destruction, and elucidating the regulation of IL-1 will advance our understanding of the onset and progression of bone and joint diseases. IL-1 has two isoforms, IL-1α and IL-1β. Both isoforms signal through the same IL-1 receptor type 1, but the activation mechanisms are completely different. In particular, IL-1β is tightly regulated by protein complexes termed inflammasomes. Recent research using innovative technologies has led to a series of discoveries about inflammasomes. This review highlights the current understanding of the activation and function of the NLRP3 (NOD-like receptor family, pyrin domain-containing 3) inflammasome in bone and joint diseases.     

Successful i-GONAD in Mice at Early Zygote Stage through In Vivo Electroporation Three Min after Intraoviductal Instillation of CRISPR-Ribonucleoprotein

Improved genome editing via oviductal nucleic acids delivery (i-GONAD) is a new technology enabling in situ genome editing of mammalian zygotes exiting the oviductal lumen, which is now available in mice, rats, and hamsters. In this method, CRISPR/Cas9 genome-editing reagents are delivered directly to the oviducts of pregnant animals (corresponding to late zygote stage). After intraoviductal instillation, electric shock to the entire oviduct was provided with a specialized electroporation (EP) device to drive the genome editing reagents into the zygotes present in the oviductal lumen. i-GONAD toward early zygotes has been recognized as difficult, because they are tightly surrounded by a cumulus cell layer, which often hampers effective transfer of nucleic acids to zygotes. However, in vivo EP three min after intraoviductal instillation of the genome-editing reagents enabled genome editing of early zygotes with an efficiency of 70%, which was in contrast with the rate of 18% when in vivo EP was performed immediately after intraoviductal instillation at Day 0.5 of pregnancy (corresponding to 13:00–13:30 p.m. on the day when vaginal plug was recognized after natural mating). We also found that addition of hyaluronidase, an enzyme capable of removing cumulus cells from a zygote, slightly enhanced the efficiency of genome editing in early zygotes. These findings suggest that cumulus cells surrounding a zygote can be a barrier for efficient generation of genome-edited mouse embryos and indicate that a three-minute interval before in vivo EP is effective for achieving i-GONAD-mediated genome editing at the early zygote stage. These results are particularly beneficial for researchers who want to perform genome editing experiments targeting early zygotes.     

Cardio-Vascular Interaction Evaluated by Speckle-Tracking Echocardiography and Cardio-Ankle Vascular Index in Hypertensive Patients

Hypertension increases arterial stiffness, leading to dysfunction and structural changes in the left atrium (LA) and left ventricle (LV). However, the effects of hypertension on the right atrium (RA) and the right ventricle are still not fully understood. The purpose of this study was to clarify whether there is an interaction not only in the left ventricular system but also in the right ventricular system in hypertensive patients with preserved LV ejection fraction. The current retrospective observational study included patients (n = 858) with some risk of metabolic abnormalities (hypertension, diabetes, and dyslipidemia) who had visited our hospital and undergone echocardiography between 2015 and 2018. Among them, we retrospectively studied 165 consecutive hypertensive patients with preserved LV ejection fraction who had echocardiography performed on the same day as a cardio-ankle vascular index (CAVI) in our hospital. The phasic function of both atria was evaluated by two-dimensional speckle-tracking echocardiography. CAVI was measured using Vasela 1500 (Fukuda Denshi^®). In the univariate analysis, CAVI was significantly correlated with LA and RA conduit function (LA conduit function, r = −0.448, p = 0.0001; RA conduit function, r = −0.231, p = 0.003). A multivariate regression analysis revealed that LA and RA conduit function was independently associated with CAVI (LA, t = −5.418, p = 0.0001; RA, t = −2.113, p = 0.036). CAVI showed a possibility that the association between heart and vessels are contained from not only LA phasic function but also RA phasic function in hypertensive patients.     

A New Indicator to Differentiate Thyroid Follicular Inclusions in Cervical Lymph Nodes from Patients with Thyroid Cancer

Nodal metastasis is crucial for determining the stage of well-differentiated thyroid cancer (WTC) in patients older than 55. Well-formed thyroid follicular inclusions (TFIs) are occasionally encountered in the cervical lymph nodes (LNs) of patients with papillary thyroid carcinoma (PTC), and it is difficult to determine whether they are true nodal metastases or ectopic thyroid tissues (ETT). This study aimed to elucidate the impact of the expression of the DNA damage response molecule TP53-binding protein 1 (53BP1) using immunofluorescence (IF) as a biomarker to differentiate TFIs in cervical LN by comparing the mutation analyses of primary thyroid cancers. The data demonstrated the necessity for the differential diagnosis of true metastases from ETT among TFIs in cervical LNs. PTC-like nuclear features using hematoxylin–eosin staining combined with immunohistochemistry for conventional biomarkers of PTC, including BRAF^V600E protein, were most helpful in identifying metastatic follicular-patterned carcinomas. In conclusion, IF analysis of 53BP1 expression could be an excellent ancillary technique to distinguish metastatic carcinoma or ETT from TFIs in LNs, particularly in cases other than BRAF^V600E-mutated PTC.     

Continuous measurements of bronchial exposure induced by radon decay products during inhalation

The deposition of radon decay products is not equal in each of the respiratory regions and as the presence of radon has been linked with an increase in lung cancer risk, it is important to calculate the deposition of radon decay products in each of the respiratory regions. Recently, many studies on the deposition of radon in respiratory regions have been simulated using wire screens. The systems and equipment used in those studies are not suitable for field measurements as their dimensions are relatively massive, nor can they measure continuously. We developed a continuous bronchial dosimeter (CBD) which is suitable for field measurements. It was designed with specifications that allow it to be remain compact. The CBD simulates the deposition of radon decay products in the different respiratory regions by the use of a combination of wire screens. Deposition in the simulated regions of the lung can be continuously estimated in various environments. The ratio of activities deposited in a simulated nasal cavity (N) and tracheobronchial (TB) regions was calculated from the results of simultaneous measurements using CBD-R (reference), CBD-N (nasal), and CBD-TB (tracheobronchial) measurement units. After aerosols were injected into the radon chamber, the ratio of N and TB depositions decreased. This results indicate that the CBD gave a good response to changes in the environment. It was found that the ratio of N and TB deposition also varied with time in each actual environment.     

A Tryptophan Prenyltransferase with Broad Substrate Tolerance from Bacillus subtilis subsp. natto

Bacillus subtilis subsp. natto secretes the ComX_natto pheromone as a quorum‐sensing pheromone to produce poly‐γ‐glutamate for biofilm formation. The amino‐acid sequence of the pheromone is Lys‐Trp‐Pro‐Pro‐Ile‐Glu, and the tryptophan residue is post‐translationally modified with a farnesyl group to form a tricyclic scaffold. Unlike other Bacillus ComX pheromones, the tryptophan residue is distant from the C‐terminal end of the precursor peptide ComX_natto. Here, we report the functional analysis of ComQ_natto, which catalyzes a unique farnesyl‐transfer reaction. ComQ_natto recognizes not only full‐length ComX_natto but also N‐ and/or C‐terminal truncated ComX_natto analogues and even a single tryptophan for modification with a farnesyl group in vitro. These results, together with the calculated kinetic parameters, suggest that ComQ_natto does not require a leader sequence for substrate recognition and is a promising enzyme with broad substrate tolerance for the synthesis of various prenylated tryptophan derivatives.     

Use of porous ceramic waste aggregates for internal curing of high-performance concrete

Internal curing has become extensively used to reduce autogenous shrinkage and consequently mitigate the high risk of early age cracking of high-performance concrete (HPC). This paper investigates the efficiency of internal wet curing provided by a new type of aggregate, "recycled waste porous ceramic coarse aggregates" (PCCA). Six different silica fume HPCs with and without the PCCA are examined with respect to measured physical and mechanical property development. Four different replacement proportions of normal weight coarse aggregate (NCA) by the PCCA have been evaluated. The results have shown a high effectiveness of the PCCA for internal curing purposes, to drastically reduce and even to completely eliminate autogenous shrinkage of HPC prepared with a very low water/binder ratio (w/b) of 0.15. It has been found that the incorporation of 40% of the PCCA leads to a non-shrinking HPC that results in an insignificant internal stress accompanied by a significant increase of the compressive strength. It should be noted that for the different proportions of the PCCA incorporated no decrease of the compressive strength has been observed at either early or later ages, as is the case with some conventional lightweight aggregates.     

Preparation of nitrogen-doped porous carbon by ammonia gas treatment and the effects of N-doping on water adsorption

Nitrogen-doped porous carbons (N-RFCC) were prepared by NH₃N₂ mixture gas treatment at high temperature during the carbonization process on resorcinol–formaldehyde cryogels. To show the role of N-doping on the adsorption behavior we carried out water adsorption, and it was found that the amount of water adsorbed is directly related to the nitrogen content over the low pressure region (P/P₀ < 0.3). Applying the theoretical water adsorption model, Horikawa–Do (HD) model, to the adsorption isotherms of N-RFCCs, we could analyze the effects of nitrogen-doping on the adsorption mechanism. Although the concentration of functional groups of N-RFCC is almost equal to that of the non-doped RFCC, which was measured by Boehm titration method, the water adsorbed amounts of N-RFCCs over the low pressure region were larger. This is due to part of the doped nitrogen atoms act as functional groups, contributing to the total concentration of functional groups. The saturated concentrations depend on the packing fraction of water molecules, which in turn depends on the pore size. The packing fractions of N-RFCCs are larger than those of RFCCs, and this could be attributed to the high affinity between water clusters and N-doped surfaces, resulting in a reduced hydrophobicity of the surface.