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The circular speed curve of the Milky Way provides a key constraint on its mass distribution, reflecting the axisymmetric component of the gravitational potential. This is especially critical in the inner Galaxy (R ≲ 4 kpc), where nonaxisymmetric structures, such as the stellar bar and nuclear stellar disk, strongly influence dynamics. However, significant discrepancies remain between circular speed curves inferred from stellar dynamical modeling and those derived from the terminal-velocity method applied to gas kinematics. To investigate this, we perform three-dimensional hydrodynamic simulations including cooling, heating, star formation, and feedback, under a realistic gravitational potential derived from stellar dynamical models calibrated to observational data. This potential includes the Galactic bar, stellar disks, dark matter halo, nuclear stellar disk, and nuclear star cluster. We generate synthetic longitude–velocity diagrams and apply the terminal-velocity method to derive circular speeds. The simulated gas reproduces the observed terminal-velocity envelope, including a steep inner rise. We find this feature arises from bar-driven noncircular motions, which cause the terminal-velocity method to overestimate circular speeds by up to a factor of 2 at R ∼ 0.4 kpc, and enclosed mass by up to a factor of 4. These results suggest that inner gas-based rotation curves can significantly overestimate central mass concentrations. The steep inner rise in gas-derived circular speeds does not require a massive classical bulge but can be explained by bar-induced streaming motions. Rather than proposing a new mechanism, our study provides a clear, Milky Way–specific demonstration of this effect, emphasizing the importance of dynamical modeling that explicitly includes noncircular motions for accurate mass inference in the inner Milky Way.

Astrophysical evidence suggests that the Sun was born near 5 kpc from the Galactic center, within the corotation radius of the Galactic bar, around 6–7 kpc. This presents challenges for outward migration due to the Jacobi energy constraint, preventing stars from easily overcoming the corotation barrier. In this study, we use test particle simulations to explore two possible migration pathways for the Sun: a “trapped” scenario, where the Sun's orbit was influenced by a slowing Galactic bar, and an “untrapped” scenario driven by dynamic spiral arms. Our results demonstrate that both mechanisms can explain how the Sun migrated from its birth radius (≈5 kpc) to its current orbital radius around 8.5–9 kpc. Furthermore, we investigate the environmental changes experienced by the Sun along these migration pathways, focusing on variations in radiation hazards and comet fluxes, which may have impacted planetary habitability. These findings highlight the dynamic nature of galactic habitability, emphasizing that the path a star takes within the Milky Way can significantly affect its surrounding environment and the potential for life. We propose a new concept of “Galactic habitable orbits,” which accounts for evolving galactic structures and their effects on stellar and planetary systems. This work contributes to a deeper understanding of the solar system's migration and its implications for habitability within the Milky Way.

Gas delivery to galactic centers powers nuclear starbursts and active galactic nuclei (AGNs), yet bar-driven inflow is generally expected to stall in a nuclear ring a few hundred parsecs across. Using three-dimensional (3D) Lagrangian hydrodynamic simulations in a fixed barred potential, we identify a bypass channel in which a fraction of the inflowing gas acquires vertical momentum, vaults across the ring, and reaches the inner few tens of parsecs. This pathway is absent in two-dimensional calculations, which instead predict long-lived stagnation at the ring. We find that the circumnuclear material within ∼50 pc originates from gas initially located outside the ring (≳300 pc) rather than from secondary inflow out of the ring itself. Successful delivery requires both a sufficiently large vertical excursion, ∣z∣ ∼ 100 pc before encountering the ring, and substantial loss of azimuthal angular momentum Lz. The resulting inflow is organized rather than chaotic: center-reaching trajectories are confined to a limited spatial region set by the scale height of the ring gas. Most bar-driven gas still accumulates near the resonance and fuels star formation in the nuclear ring, but the vaulting stream selects a modest yet sufficient fraction that penetrates to the circumnuclear disk. These results suggest that intrinsically 3D gas motions help link nuclear starbursts, AGN fueling, and the frequent misalignment of nuclear disks with respect to their host galaxies.

Fusobacterium nucleatum is associated with the progression of colorectal cancer. Thus, the possibility of preventing colorectal cancer or its progression by targeting F. nucleatum has been explored. As F. nucleatum is associated with periodontitis, we analysed whether treating periodontitis could influence F. nucleatum abundance in the colon. Patients with colorectal tumours who underwent colonoscopy were recruited. Patients diagnosed with periodontitis by a dentist were treated for approximately 3 months. Endoscopic resection of colorectal tumours was performed after periodontitis treatment, and resected tumours were pathologically classified as high-(HGD) or low-grade dysplasia (LGD). Saliva and stool samples were collected before and after the treatment. Of the 58 patients with colorectal tumours, 31 were included in the study, 16 showed improvement in periodontitis, and 11 showed no improvement. Stool F. nucleatum levels before treatment were significantly lower in the LGD group than in the HGD group. A significant decrease in faecal F. nucleatum levels was observed in patients who underwent successful treatment but not in those whose treatment failed. Salivary F. nucleatum levels were not altered in patients despite periodontal treatment. Thus, successful periodontitis treatment reduces stool F. nucleatum levels and may aid research on periodontitis and suppression of colorectal cancer development.

We present Atacama Large Millimeter/submillimeter Array (ALMA) imaging of molecular gas across the full star-forming disk of the barred spiral galaxy M83 in CO(J = 1–0). We jointly deconvolve the data from ALMA’s 12 m, 7 m, and Total Power arrays using the MIRIAD package. The data have a mass sensitivity and resolution of 104 M ⊙ (3σ) and 40 pc—sufficient to detect and resolve a typical molecular cloud in the Milky Way with a mass and diameter of 4 × 105 M ⊙ and 40 pc, respectively. The full disk coverage shows that the characteristics of molecular gas change radially from the center to outer disk, with the locally measured brightness temperature, velocity dispersion, and integrated intensity (surface density) decreasing outward. The molecular gas distribution shows coherent large-scale structures in the inner part, including the central concentration, offset ridges along the bar, and prominent molecular spiral arms. However, while the arms are still present in the outer disk, they appear less spatially coherent, and even flocculent. Massive filamentary gas concentrations are abundant even in the interarm regions. Building up these structures in the interarm regions would require a very long time (≳100 Myr). Instead, they must have formed within stellar spiral arms and been released into the interarm regions. For such structures to survive through the dynamical processes, the lifetimes of these structures and their constituent molecules and molecular clouds must be long (≳100 Myr). These interarm structures host little or no star formation traced by Hα. The new map also shows extended CO emission, which likely represents an ensemble of unresolved molecular clouds.

Metallicity gradients refer to the sloped radial profiles of the metallicities of gas and stars and are commonly seen in disk galaxies. A well-defined metallicity gradient of the Galactic disk is observed particularly well with classical Cepheids, which are good stellar tracers thanks to their period–luminosity relation, allowing precise distance estimation and other advantages. However, the measurement of the inner-disk gradient has been impeded by the incompleteness of previous samples of Cepheids and the limitations of optical spectroscopy in observing highly reddened objects. Here we report the metallicities of 16 Cepheids measured with high-resolution spectra in the near-infrared YJ bands. These Cepheids are located at 3–5.6 kpc in Galactocentric distance, R GC, and reveal the metallicity gradient in this range for the first time. Their metallicities are mostly between 0.1 and 0.3 dex in [Fe/H] and more or less follow the extrapolation of the metallicity gradient found in the outer part, R GC > 6.5 kpc. The gradient in the inner disk may be shallower or even flat, but the small sample does not allow the determination of the slope precisely. More extensive spectroscopic observations would also be necessary for studying minor populations, if any, with higher or lower metallicities that were reported in previous literature. In addition, the 3D velocities of our inner-disk Cepheids show a kinematic pattern that indicates noncircular orbits caused by the Galactic bar, which is consistent with the patterns reported in recent studies on high-mass star-forming regions and red giant branch stars.

Background/Aim: Cervical lymph node metastasis worsens oral cancer prognosis. Cancer cells with high metastatic ability can delay or resist apoptosis and survive in the floating condition during circulation. The involved genes and pathways in this process remain largely unknown. This study aimed to establish an oral cancer cell line adapted to suspension culture by in vitro selection and perform gene expression analysis. Materials and Methods: The oral cancer cell subline adapted to suspension culture was isolated by in vitro selection from the oral cancer cell line, HSC-3. The transcriptome profiles of HSC-3 and its subline were compared using gene expression microarrays. Gene Ontology (GO) enrichment analysis, Gene Set Enrichment Analysis (GSEA), and Ingenuity Pathway Analysis (IPA) were performed to predict the involved pathways and molecules in cancer progression. Results: The subline was designated as HSC-3S5. The cellular viability of HSC-3S5 cells at the suspension culture was higher than that of HSC-3 cells. A total of 961 genes were differentially expressed between HSC-3 and HSC-3S5 cells under the threshold cut-off (FDR-adjusted p-value of <0.05 and absolute fold change of >1.5). GO terms, such as growth regulation, were enriched in the DEGs. GSEA revealed the association between the DEGs and significant gene sets, including metastasis and stemness. IPA predicted that the proliferation-related pathways were enhanced while the apoptotic pathway was inhibited in HSC-3S5 cells compared to HSC-3 cells. Conclusion: Our transcriptome analysis revealed several potentially activated pathways and molecules in the floating-adapted oral cancer cells and indicated molecular implications for cancer progression.

Background The objectives of this retrospective study were to evaluate the usefulness of computed tomography lymphography (CTL) and to clarify the optimal timing of CTL in sentinel lymph node (SLN) mapping of clinically N0 early oral cancer. Methods Twenty patients with clinically N0 early oral cancer underwent CTL with a 128 multi-detector row CT scanner to detect SLN the day before resection of primary tumor and SLN biopsy with indocyanine green (ICG) fluorescence guidance. CT scanning was performed in the first 10 patients at 2, 5, and 10 min after submucosal injection of iopamidol and in the remaining 10 patients at 2, 3.5, 5, and 10 min after the injection of contrast medium. We evaluated the SLN detection rate at each scan timing and the number and location of SLNs. We evaluated whether CTL-enhanced SLNs could be identified intraoperatively as ICG fluorescent lymph nodes. Results SLNs were detected by CTL in 19 of the 20 patients (95.0%), and the mean number of SLNs was 2 (range, 1–4). All SLNs were located on the ipsilateral side; 35 of 37 SLNs were located at level I and II, and 2 SLNs were lingual lymph nodes. All SLNs could be detected 2 min and 3.5–5 min after contrast medium injection, and CTL-enhanced SLNs could be identified intraoperatively as fluorescent lymph nodes. Conclusions CTL could facilitate the detection of SLNs in early oral cancer, and the optimal timing of CT scanning was at 2 and 5 min after injection of contrast medium.

Background/Aim: Cancer cells with high anchorage independence can survive and proliferate in the absence of adhesion to the extracellular matrix. Under anchorage-independent conditions, cancer cells adhere to each other and form aggregates to overcome various stresses. In this study, we investigated the cytomorphology and gene expression signatures of oral cancer cell aggregates. Materials and Methods: Two oral cancer-derived cell lines, SAS and HSC-3 cells, were cultured in a low-attachment plate and their cytomorphologies were observed. The transcriptome between attached and detached SAS cells was examined using gene expression microarrays. Subsequently, gene enrichment analysis and Ingenuity Pathway Analysis were performed. Gene expression changes under attached, detached, and re-attached conditions were measured via RT-qPCR. Results: While SAS cells formed multiple round-shaped aggregates, HSC-3 cells, which had lower anchorage independence, did not form aggregates efficiently. Each SAS cell in the aggregate was linked by desmosomes and tight junctions. Comparative transcriptomic analysis revealed 1,698 differentially expressed genes (DEGs) between attached and detached SAS cells. The DEGs were associated with various functions and processes, including cell adhesion. Moreover, under the detached condition, the expression of some epithelial genes (DSC3, DSP, CLDN1 and OCLN) were up-regulated. The changes in both cytomorphology and epithelial gene expression under the detached condition overall returned to their original ones when cells re-attached. Conclusion: The results suggest specific cytomorphological and gene expression changes in oral cancer cell aggregates. Our findings provide insights into the mechanisms underlying anchorage-independent oral cancer cell aggregation and reveal previously unknown potential diagnostic and therapeutic molecules.

Dentigerous cysts are common odontogenic cysts of the jaw but are rarely associated with supernumerary teeth. Few cases of large dentigerous cysts associated with anterior maxillary supernumerary teeth have been reported. The English literature has documented only four cases of dentigerous cysts>40 mm in diameter associated with supernumerary teeth. A 47-year-old man was referred to our hospital, complaining of minor pain in the maxillary gingiva. Computed tomography revealed a well-defined oval unilocular radiolucent lesion (50×45×35 mm) in the right maxilla, including two impacted supernumerary teeth. A dentigerous cyst associated with impacted anterior maxillary supernumerary teeth was diagnosed. The two impacted teeth were surgically removed, and the cyst was enucleated using the Caldwell-Luc approach. Histopathology confirmed the diagnosis of a large dentigerous cyst associated with impacted anterior maxillary supernumerary teeth. The postoperative course has been uneventful for two years. We also reviewed the relevant English literature.