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The mandibular condylar cartilage (MCC) is an essential component of the temporomandibular joint, which orchestrates the vertical growth of the mandibular ramus through endochondral ossification with distinctive modes of cell differentiation. Parathyroid hormone–related protein (PTHrP) is a master regulator of chondrogenesis; in the long bone epiphyseal growth plate, PTHrP expressed by resting zone chondrocytes promotes chondrocyte proliferation in the adjacent layer. However, how PTHrP regulates chondrogenesis in the MCC remains largely unclear. In this study, we used a Pthrp-mCherry knock-in reporter strain to map the localization of PTHrP+ cells in the MCC and define the function of PTHrP in the growing mandibular condyle. In the postnatal MCC of Pthrp mCherry/+ mice, PTHrP-mCherry was specifically expressed by cells in the superficial layer immediately adjacent to RUNX2-expressing cells in the polymorphic layer. PTHrP ligands diffused across the polymorphic and chondrocyte layers where its cognate receptor PTH1R was abundantly expressed. We further analyzed the mandibular condyle of Pthrp mCherry/mCherry mice lacking functional PTHrP protein (PTHrP-KO). At embryonic day (E) 18.5, the condylar process and MCC were significantly truncated in the PTHrP-KO mandible, which was associated with a significant reduction in cell proliferation across the polymorphic layer and a loss of SOX9+ cells in the chondrocyte layers. The PTHrP-KO MCC showed a transient increase in the number of Col10a1+ hypertrophic chondrocytes at E15.5, followed by a significant loss of these cells at E18.5, indicating that superficial layer–derived PTHrP prevents premature chondrocyte exhaustion in the MCC. The expression of Runx2, but not Sp7, was significantly reduced in the polymorphic layer of the PTHrP-KO MCC. Therefore, PTHrP released from cells in the superficial layer directly acts on cells in the polymorphic layer to promote proliferation of chondrocyte precursor cells and prevent their premature differentiation by maintaining Runx2 expression, revealing a unique PTHrP gradient-directed mechanism that regulates MCC chondrogenesis. [ABSTRACT FROM AUTHOR]

Paciente masculino de 59 años, con antecedentes patológicos personales de tabaquismo, enfermedad pulmonar obstructiva crónica y obesidad mórbida. Un mes antes del ingreso comenzó con tos seca, dolor en punta de costado izquierda y astenia marcada; se interpretó como una neumopatía inflamatoria de la comunidad, que requirió de varios tratamientos antibióticos. No hubo mejoría y acudió al Hospital “Arnaldo Milián Castro” para estudio. El ecocardiograma transtorácico realizado mostró un derrame pericárdico de gran cuantía y una imagen tumoral en la aurícula izquierda que infiltraba al pericardio. Hubo empeoramiento de los síntomas, presentó cuadro de hipotensión arterial y bradicardia, cayó en parada cardiorrespiratoria y lo declararon fallecido con los diagnósticos de neoplasia cardíaca y choque cardiogénico. Los hallazgos en la necropsia permitieron el diagnóstico de pericarditis constrictiva por infiltración de adenocarcinoma moderadamente diferenciado de pulmón con carcinomatosis pleural y pericárdica; falleció por cuadro de choque cardiogénico. Los tumores cardíacos más frecuentes son los de origen metastásico y, dentro de ellos, los carcinomas de pulmón y mama, los melanomas y las leucemias.

Background and Objective The periodontal ligament ( PDL) is characterized by rapid turnover, high remodeling capacity and high inherent regenerative potential compared with other connective tissues. Periostin, which is highly expressed in the fibroblasts in the PDL, has been widely discussed in relation to collagen fibrillogenesis in the PDL. Recently, several reports have indicated periostin in cell migration. The aim of this study was to examine whether human PDL fibroblasts ( hPDLFs) with high levels of periostin expression promote the migration of human bone marrow mesenchymal stem cells ( hMSCs). Material and Methods The migration of hMSCs was examined by transwell chamber migration assay under different conditions: medium alone, hPDLFs, human dermal fibroblasts, recombinant periostin, integrin αvβ3 blocking antibody (anti- CD51/61 antibody) and inhibitors of FAK ( PF431396) and PI3 K ( LY294002). Phosphorylation of FAK and Akt in hMSCs under stimulation of periostin was examined by western blotting. Results The migration assay revealed that the number of migrated hMSCs by hPDLFs was significantly larger than those by dermal fibroblasts, periostin small interfering RNA hPDLFs and medium alone. Furthermore, recombinant periostin also strongly induced hMSC migration. The addition of anti- CD51/61 antibody, PF431396 and LY294002 caused a significant reduction in the number of migrated hMSCs respectively. The anti- CD51/61 antibody inhibited both FAK and Akt phosphorylations under periostin stimulation. PF431396 inhibited both FAK and Akt phosphorylations. LY294002 inhibited only Akt phosphorylation, and FAK phosphorylation was not influenced under periostin stimulation. Conclusion Periostin expression in hPDLFs promotes the migration of hMSCs through the αvβ3 integrin/ FAK/ PI3 K/ Akt pathway in vitro. [ABSTRACT FROM AUTHOR]

Fundamento: El simbléfaron posquirúrgico es una complicación oftalmológica que consiste en la adhesión total o parcial de la conjuntiva tarsal y el globo ocular causado por una cicatriz; donde resultan complicaciones secundarias que afectan la anatomía oculofacial y la función visual. Objetivo: Ilustrar el resultado de la autoplastia conjuntival autóloga como tratamiento del simbléfaron posquirúrgico. Presentación de caso: Se presenta un caso de simbléfaron posquirúrgico que luego de someterse a varias cirugías de pterigion evolucionó con insuficiencia de células límbicas, conjuntivalización de la córnea y simbléfaron. El paciente evolucionó favorablemente luego de recibir tratamiento quirúrgico por autoplastia conjuntival autóloga, se recuperó la motilidad ocular y se redujo el astigmatismo y un palpable ahorro de recursos sin sacrificar la efectividad del proceder quirúrgico. Conclusiones: El tratamiento del simbléfaron posquirúrgico mediante la autoplastia conjuntival autóloga, permite adoptar una conducta adecuada, reportando un saldo favorable en la recuperación del paciente. DeCS: CONJUNTIVA/cirugía; TRASPLANTE AUTÓLOGO; PROCEDIMIENTOS QUIRÚRGICOS OFTALMOLÓGICOS/métodos. Palabras clave: Simbléfaron, autoplastias conjuntivales, autoinjertos conjuntivales, procedimientos quirúrgicos oftalmológicos.

Background: Quality control (QC) of carbapenem susceptibility testing for Gram-negative bacteria faces challenges due to limited measuring ranges and the lack of suitable QC strains. This study aimed to select and evaluate QC strains for meropenem antimicrobial susceptibility testing (AST) through a pilot external quality assessment (EQA)., Methods: Candidate QC strains for meropenem AST were selected based on primary AST data and genomic information from the Japan Antimicrobial Resistant Bacterial Bank. Phenotype stability was verified through serial passaging and MIC comparison with original strains. The validated broth microdilution method was used to determine the target MIC value in a pilot EQA involving 47 clinical laboratories in Japan using ten different AST methods., Results: Two strains, Citrobacter freundii JBBDAJB-19-0032 (Strain-A) and Enterobacter hormaechei subsp. steigerwaltii JBEBAAB-19-0102 (Strain-B), both carrying bla IMP-1 , were selected as candidate QC strains. The meropenem MICs for Strain-A and Strain-B were 4 mg/L and 2 mg/L, respectively. In the pilot EQA, 43 laboratories reported appropriate results for Strain-A and 40 laboratories reported appropriate results for Strain-B. The MIC range was 2-8 mg/L for Strain-A and 1-4 mg/L for Strain-B. However, 19 and 12 laboratories, respectively, reported out-of-range MICs using AST plates on the MicroScan WalkAway. Inappropriate results were reported by four and seven laboratories, respectively, using common methods for Strain-A and Strain-B, respectively., Conclusions: The candidate QC strains selected for this study are suitable for meropenem AST EQA, except when the measuring range of certain methods does not match their QC range., Competing Interests: Declaration of competing interest JH is an employee of bioMérieux Japan Ltd. All other authors have no conflicts of interest to declare., (Copyright © 2024 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.)

Objectives: The suppression of antimicrobial-resistant bacteria (ARB) is an important issue worldwide. In recent years, the presence of various ARB in the oral cavity has been reported, but the details remain unclear. Therefore, we aimed to isolate ARB from the oral cavity and investigate the factors affecting ARB colonization., Methods: Third-generation cephalosporin- or carbapenem-resistant gram-negative bacteria (GN-ARB) were isolated from the oral and nasal cavities of 514 participants who visited the dental clinic, and the whole-genome sequences of all the isolates were obtained. Additionally, the tongue microbiota was analysed by 16S rRNA sequencing. The correlations of GN-ARB isolation with clinical status and the tongue microbiota were subsequently investigated., Results: Among 514 participants, 131 and 13 GN-ARB strains were isolated from the oral cavities of 93 participants (18.1 %) and from the nasal cavities of 12 participants (2.3 %). The ARB were mainly affiliated with Acinetobacter spp. (39.7 %), Pseudomonas spp. (14.5 %) and Stenotrophomonas maltophilia (18.3 %). We found a correlation between the isolation of oral GN-ARB and ageing/the number of teeth. There were no significant correlations between the presence of GN-ARB and tongue microbiota composition., Conclusions: Our results suggest that the oral cavity is an important potential reservoir of GN-ARB and that ageing and tooth loss are risk factors for the presence of GN-ARB in the oral cavity., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Hitoshi Komatsuzawa reports financial support was provided by 10.13039/100009619The Japan Agency for Medical Research and Development (10.13039/100009619AMED). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

The patho-mechanism of apolipoprotein variant, APOE4, the strongest genetic risk for late-onset Alzheimer's disease (AD) and longevity, remains unclear. APOE's neighboring gene, TOMM40 (mitochondria protein transport channel), is associated with brain trauma outcome and aging-related cognitive decline, however its role in AD APOE4-independently is controversial. We report that TOMM40 is prone to transcription readthrough into APOE that can generate spliced TOMM40-APOE mRNA chimera (termed T9A2) detected in human neurons and other cells and tissues. T9A2 translation tethers APOE (normal APOE3 or APOE4) to near-full-length TOM40 that is targeted to mitochondria. Importantly, T9A2-APOE3 boosts mitochondrial bioenergetic capacity and decreases oxidative stress significantly more than T9A2-APOE4 and APOE3, and lacking in APOE4. We describe detailed interactomes of these actors that may inform about the activities and roles in pathogenesis. T9A2 uncovers a new candidate pathway for mitochondria regulation and oxidative stress-protection that are impaired in APOE4 genotypes and could initiate neurodegeneration.

Calcification plays a key role in biological processes, and breakdown of the regulatory mechanism results in a pathological state such as ectopic calcification. We hypothesized that ENPP1, the enzyme that produces the calcification inhibitor pyrophosphate, is transcriptionally regulated by Nrf2, and that Nrf2 activation augments ENPP1 expression to inhibit ectopic calcification. Cell culture experiments were performed using mouse osteoblastic cell line MC3T3-E1. Nrf2 was activated by 5-aminolevulinic acid and sodium ferrous citrate. Nrf2 overexpression was induced by the transient transfection of an Nrf2 expression plasmid. ENPP1 expression was monitored by real-time RT-PCR. Because the promoter region of ENPP1 contains several Nrf2-binding sites, chromatin immunoprecipitation using an anti-Nrf2 antibody followed by real-time PCR (ChIP-qPCR) was performed. The relationship between Nrf2 activation and osteoblastic differentiation was examined by alkaline phosphatase (ALP) and Alizarin red staining. We used mice with a hypomorphic mutation in ENPP1 (ttw mice) to analyze whether Nrf2 activation inhibits ectopic calcification. Nrf2 and Nrf2 overexpression augmented ENPP1 expression and inhibited osteoblastic differentiation, as indicated by ALP expression and calcium deposits. ChIP-qPCR showed that some putative Nrf2-binding sites in the ENPP1 promoter region were bound by Nrf2. Nrf2 activation inhibited ectopic calcification in mice. ENPP1 gene expression was transcriptionally regulated by Nrf2, and Nrf2 activation augmented ENPP1 expression, leading to the attenuation of osteoblastic differentiation and ectopic calcification in vitro and in vivo. Nrf2 activation has a therapeutic potential for preventing ectopic calcification.

The emergence of drug-resistant bacteria, particularly methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE), has increased the need to discover novel antimicrobial agents that are effective against these species. Here, we describe the identification and purification of the mutacin BHT-B-like gene locus and bacteriocin peptide from Streptococcus ursoris , which is closely related to Streptococcus ratti ; hence, we named this bacteriocin ursoricin. Ursoricin is a cationic, chromosome-encoded peptide that has potent antimicrobial effects against Gram-positive pathogens, including MRSA and VRE, with minimum inhibitory concentrations in the micromolar range. Ursoricin also inhibits the biofilm formation of high biofilm-forming S. aureus . Antibacterial activity was retained after treatment at 100°C for 60 min at a pH range of 3-9 and was partially reduced by treatment with proteinase K for 2 h (63% residual activity). The potent anti-MRSA, anti-VRE, and antibiofilm effects of ursoricin suggest that it is a possible candidate for the treatment of MRSA, VRE, and biofilm-associated infections., Importance: The emergence of multidrug-resistant bacteria worldwide has posed a significant public health threat and economic burdens that make the identification and development of novel antimicrobial agents urgent. Bacteriocins are promising new agents that exhibit antibacterial activity against a wide range of human pathogens. In this study, we report that the bacteriocin produced by Streptococcus ursoris showed good antibacterial activity against a wide range of Staphylococcus aureus and enterococcus strains, particularly methicillin-resistant Staphylococcus aureus , vancomycin-resistant enterococci, and high biofilm-forming S. aureus . Interestingly, this bacteriocin had a stronger effect on S. aureus than on Staphylococcus epidermidis , which is a major commensal bacterium in human skin; this result is important when considering the disturbance of bacterial flora, especially on the skin, mediated by the application of antibacterial agents., Competing Interests: The authors declare no conflict of interest.

Mandibular retrognathism occurs by insufficient mandibular growth and causes several issues, such as respiratory difficulty and diminished masticatory function. At present, functional orthodontic appliances are used for stimulating mandibular growth in pediatric cases. However, the effectiveness of functional appliances is not always stable in daily practices. A more effective, reliable, and safer therapeutic method for mandibular growth promotion would be helpful for growing mandibular retrognathism patients. As we previously discovered that nutritional supplementation of myo-inositol in growing mice specifically increases mandibular endochondral growth, we performed preclinical animal experiments in rabbits in this study. Briefly, six-week-old male Japanese white rabbits were fed with or without myo-inositol supplementation in laboratory chow until 25 weeks old, and 3D image analysis using micro CT data and histological examinations was done. Myo-inositol had no systemic effect, such as femur length, though myo-inositol specifically augmented the mandibular growth. Myo-inositol increased the thickness of mandibular condylar cartilage. We discovered that the nutritional supplementation of myo-inositol during the growth period specifically augmented mandibular growth without any systemic influence, even in rabbits. Our results suggest the possibility of clinical use of myo-inositol for augmentation of the mandibular growth in growing mandibular retrognathism patients in the future.