Discovery of DS44470011: An oral hypoxia-inducible factor prolyl hydroxylase inhibitor for the treatment of renal anemia.

Inhibition of the hypoxia-inducible factor prolyl hydroxylase (HIF-PHD) represents a promising strategy for discovering next-generation treatments for renal anemia. We identified a pyrimidine core with HIF-PHD inhibitory activity based on scaffold hopping of FG-2216 using crystal structures of HIF-PHD2 in complex with compound. By optimizing the substituents at the 2- and 6- positions of the pyrimidine core, we discovered DS44470011, which improves the effectiveness of erythropoietin (EPO) release in cells. Oral administration of DS44470011 to cynomolgus monkeys increased plasma EPO levels.

Dual near-infrared II laser modulates the cellular redox state of T cells and augments the efficacy of cancer immunotherapy.

Immunotherapy, including immune checkpoint inhibitors, has revolutionized cancer treatment, but only a minor fraction of patients shows durable responses. A new approach to overcome this limitation is yet to be identified. Recently, we have shown that photobiomodulation (PBM) with near-infrared (NIR) light in the NIR-II window reduces oxidative stress and supports the proliferation of CD8+ T cells, suggesting that PBM with NIR-II light could augment anti-cancer immunity. Here, we report a novel approach to support tumor-infiltrating CD8+ T cells upon PBM with NIR-II laser with high tissue penetration depth. Brief treatments of a murine model of breast cancer with dual 1064 and 1270 nm lasers reduced the expression of the programmed cell death protein 1 (PD-1) in CD8+ T cells in a syngeneic mouse model of breast cancer. The direct effect of the NIR-II laser treatment on T cells was confirmed by the enhanced tumor growth delay by the adoptive transfer of laser-treated CD8+ T cells ex vivo against a model tumor antigen. We further demonstrated that specific NIR-II laser parameters augmented the effect of the immune checkpoint inhibitor on tumor growth. PBM with NIR-II light augments the efficacy of cancer immunotherapy by supporting CD8+ T cells. Unlike the current immunotherapy with risks of undesirable drug-drug interactions and severe adverse events, the laser is safe and low-cost. It can be broadly combined with other therapy without modification to achieve clinical significance. In addition, our study established a path to develop a novel laser-based therapy to treat cancer effectively.

CT in osteoarthritis: its clinical role and recent advances.

Computed tomography (CT) is a widely available imaging method and considered as one of the most reliable techniques in bone assessment. Although CT has limited tissue contrast and needs radiation exposure, it has several advantages like fast scanning time and high spatial resolution. In this regard, CT has unique roles in osteoarthritis (OA) and its variable utilities have been reported. Hence, this review highlights the clinical role of CT in OA of representative joints. In addition, CT showed the several technical advancements recently, for example, acquiring the CT image with standing, obtaining the dual-energy data, and novel photon-counting detector development. Therefore, the recent studies and potential utility of these new CT systems in OA are also discussed.

Preoperative prediction for mastoid extension of middle ear cholesteatoma using temporal subtraction serial HRCT studies.

OBJECTIVES: This study investigated the utility of temporal subtraction computed tomography (TSCT) obtained with temporal bone high-resolution computed tomography (HRCT) for the preoperative prediction of mastoid extension of middle ear cholesteatomas. METHODS: Twenty-eight consecutive patients with surgically proven middle ear cholesteatomas were retrospectively evaluated. The presence of black color in the mastoid region on TSCT suggested progressive changes caused by bone erosion. Enlarged width of the anterior part of mastoid on HRCT was interpreted as suggestive of mastoid extension. Fisher's exact test was used to compare the widths and black color on TSCT for cases with and without mastoid extension. The diagnostic accuracy of TSCT and HRCT for detecting mastoid extension and interobserver agreement during the evaluation of black color on TSCT were calculated. RESULTS: There were 15 cases of surgically proven mastoid extension and 13 cases without mastoid extension. Patients with black color on TSCT were significantly more likely to have a mastoid extension (p < 0.001). The sensitivity and specificity of TSCT were 0.93 and 1.00, respectively. Patients in whom the width of the anterior part of the mastoid was enlarged were significantly more likely to have a mastoid extension (p = 0.007). The sensitivity and specificity of HRCT to detect the width of the anterior part of the mastoid were 0.80 and 0.77, respectively. Interobserver agreement during the evaluation of TSCT findings was good (k = 0.71). CONCLUSIONS: This novel TSCT technique and preoperative evaluations are useful for assessing mastoid extension of middle ear cholesteatomas and making treatment decisions. KEY POINTS: •TSCT shows a clear black color in the mastoid region when the middle ear cholesteatoma is accompanied by mastoid extension. •TSCT obtained with preoperative serial HRCT of the temporal bone is useful for assessing mastoid extension of middle ear cholesteatomas.

The Potential of a Stroke Registry Using Diagnosis Procedure Combination Data from All Hospitals in a Japanese Prefecture.

OBJECTIVES: In Japan, many hospitals have joined the diagnosis procedure combination/per-diem payment system (DPC/PDPS), which provides unified information about inpatients. DPC data are digitized, and the number of participating hospitals has increased recently. Herein, we evaluated the potential of a stroke registry constructed using these unified DPC data from all hospitals in the Iwate Prefecture, Japan. METHODS: The proportion of cerebrovascular disease (CVD) cases registered by DPC-participating hospitals was calculated and compared with all registered cases in the Iwate Stroke Registry in 2008-2017. The cases were categorized based on sex, age-groups, stroke subtypes, and first-ever onset or recurrence onset. Based on the registered cases in the stroke registry, the accuracy of the CVD cases extracted by the disease name from DPC data of a typical core hospital and a typical noncore hospital was evaluated. RESULTS: Of the 71 hospitals with 9,992 beds in the Iwate Prefecture in 2018, 50 hospitals with 8,316 beds participated in the DPC system. The proportion of registered cases from participating hospitals was 95.2% (44,779/47,018) for all stroke types (95.6% men and 94.9% women), 94.3% for cerebral infarction, 97.0% for intracerebral hemorrhage, and 98.7% for subarachnoid hemorrhage, whereas it was 95.7% for first-ever onset and 94.1% for recurrent onset. The proportion of registered cases decreased with increasing patient age. Attending doctors and researchers registered 486 and 41 CVD cases from the core and noncore hospitals, respectively, whereas 455 and 46 CVD cases were extracted from the DPC data of these hospitals, respectively. This yielded 86.6% sensitivity, 99.3% specificity, 92.5% positive predictive value, and 98.7% negative predictive value for the core hospital; these values were 92.7%, 98.6%, 82.6%, and 99.5%, respectively, for the noncore hospital. DISCUSSION/CONCLUSIONS: The stroke registry constructed using DPC data from all hospitals of Iwate Prefecture appears to be adequately complete and accurate.

Comprehensive radiological features of laryngeal sarcoidosis: cases series and systematic review.

PURPOSE: To comprehensively summarize the characteristic radiological findings of laryngeal sarcoidosis. METHODS: We reviewed patients with laryngeal sarcoidosis who underwent computed tomography (CT) and/or magnetic resonance imaging (MRI) and included 8 cases from 8 publications that were found through a systematic review and 6 cases from our institutions. Two board-certified radiologists reviewed and evaluated the radiological images. RESULTS: Almost all cases exhibited supraglottic lesions 13/14 (92.9%) and most of them involved aryepiglottic folds (12/13, 92.3%), epiglottis (11/14, 78.6%), and arytenoid region (10/14, 71.4%). Most lesions were bilateral (12/14, 85.7%). All cases showed well-defined margins and a diffuse swelling appearance (14/14, 100%). Non-contrast CT revealed a low density (4/5, 80%). The contrast-enhanced CT showed a slight patchy enhancement predominantly at the margin of the lesion in most cases (12/13, 92.3%). In one case, T2-weighted images showed high signal intensity peripherally and low signal intensity centrally (1/1, 100%). Gadolinium-enhanced MRI showed moderate heterogeneous enhancement predominantly at the margin of the lesion (2/2, 100%). In one case, diffusion-weighted imaging showed intermediate signal intensity; the apparent diffusion coefficient value was 2.4 × 10-3 mm2/s. The larynx was the only region affected by sarcoidosis in 57.1% (8/14) of the cases. Involvement of the neck lymph nodes and distant organs was observed in 4/14 (28.6%) patients, respectively. CONCLUSION: We summarized the CT and MRI findings of patients with laryngeal sarcoidosis. Knowledge of these characteristics is expected to facilitate prompt diagnosis and appropriate management.

Radiological features of human papillomavirus-related multiphenotypic sinonasal carcinoma: systematic review and case series.

PURPOSE: To comprehensively summarize the radiological characteristics of human papillomavirus (HPV)-related multiphenotypic sinonasal carcinomas (HMSCs). METHODS: We reviewed the findings for patients with HMSCs who underwent computed tomography (CT) and/or magnetic resonance imaging (MRI) and included nine cases from nine publications that were identified through a systematic review and three cases from our institution. Two board-certified radiologists reviewed and evaluated the radiological images. RESULTS: The locations in almost all cases included the nasal cavity (11/12, 91.7%). The involved paranasal sinuses included the ethmoid sinus (6/12, 50.0%) and maxillary sinus (3/12, 25.0%). The mean long diameter of the tumors was 46.3 mm. The margins in 91.7% (11/12) of the cases were well-defined and smooth. Heterogeneous enhancement on contrast-enhanced CT, heterogeneous high signal intensities on T2-weighted images and heterogeneous enhancement on gadolinium-enhanced T1-weighted images were noted in 2/2, 5/5, and 8/8 cases, respectively. Mean apparent diffusion coefficient values in two cases of our institution were 1.17 and 1.09 × 10-3 mm2/s. Compressive changes in the surrounding structures were common (75%, 9/12). Few cases showed intraorbital or intracranial extension. None of the cases showed a perineural spread, neck lymph node metastasis, or remote lesions. CONCLUSIONS: We summarized the CT and MRI findings of HMSCs. Knowledge of such characteristics is expected to facilitate prompt diagnosis and appropriate management.

Inferior vena cava diameter on CT angiography predicts mesenteric angiography positive for extravasation in colonic diverticular bleeding.

PURPOSE: Transcatheter arterial embolization (TAE) for colonic diverticular bleeding (CDB), an established procedure for hemostasis, is sometimes complicated by spontaneous hemostasis and unclear bleeding site on angiography despite active arterial bleeding on preoperative computed tomography angiography (CTA). Therefore, to investigate and increase the feasibility of TAE, this retrospective study evaluates the clinical and radiological features related to positive extravasation on angiography. MATERIAL AND METHODS: Sixty CDB patients with extravasation on CTA underwent TAE between January 2011 and February 2021 and were divided into extravasation-positive (P-group; n = 25) and -negative groups (N-group; n = 35) based on the superior or inferior mesenteric angiography. Patient characteristics, laboratory findings, the diameter of the inferior vena cava (IVCD), the diameter of superior and inferior mesenteric veins, and technical outcomes were evaluated. RESULTS: TAE was successful in 24 patients in the P-group (96%) and 14 in the N-group (40%) (p < 0.001). Univariate analysis revealed "usage of anticoagulant" (p < 0.05) and "larger IVCD (p < 0.05) on preoperative CTA" to be significant predictors of positive extravasation. In the multivariate analysis, IVCD remained significant with an adjusted odds ratio of 1.17. The IVCD cutoff value was 13.6 mm (area under the curve = 0.72, sensitivity = 84.0%, specificity = 54.3%). There were no significant differences in other parameters. CONCLUSION: Measurement of IVCD in CDB with the cutoff value of 13.6 mm can be a simple and useful indicator to predict the detectability of extravasation following TAE procedures.

[Symptomatic arachnoid cyst in an elderly patient who developed motor aphasia].

The patient was an 83-year-old woman with a history of breast cancer, distal right radial edge bone fracture, and cervical spine symptoms who had been diagnosed with an arachnoid cyst 9 years previously. She was examined by a nearby doctor, because of an approximately 1-year history of reduced verbal output; she also begun experiencing difficulties with walking. However, she was diagnosed with aging, a history of cervical spondylosis, and the effects of past fractures.At the time of this consultation, she was conscious and lucid, with mild right-sided hemiparesis, was unable to write, and had mild motor aphasia. Head magnetic resonance imaging revealed an arachnoid cyst (longer axis: 10 cm) in the left frontal lobe that did not take up contrast media. There was also a midline shift. The cause of the right hemiparesis and motor aphasia was probably compression of the left frontal lobe by the arachnoid cyst.We performed excision of the cyst wall by craniotomy and placed a cyst-peritoneal shunt under general anesthesia. At approximately one week after surgery, the patient was able to write and her motor aphasia improved. She was discharged 20 days after the operation.It is rare for an arachnoid cyst to increase in size after childhood. In the present case, surgical treatment led to a good outcome in an elderly patient with a symptomatic arachnoid cyst. Arachnoid cysts rarely increase in size. These cysts may become symptomatic in elderly people after lying clinically dormant for a long time.

Fast and Durable Intraoperative Near-infrared Imaging of Ovarian Cancer Using Ultrabright Squaraine Fluorophores.

The residual tumor after surgery is the most significant prognostic factor of patients with epithelial ovarian cancer. Near-infrared (NIR) fluorescence-guided surgery is actively utilized for tumor localization and complete resection during surgery. However, currently available contrast-enhancing agents display low on-target binding, unfavorable pharmacokinetics, and toxicity, thus not ideal for clinical use. Here we report ultrabright and stable squaraine fluorophores with optimal pharmacokinetics by introducing an asymmetric molecular conformation and surface charges for rapid transporter-mediated cellular uptake. Among the tested, OCTL14 shows low serum binding and rapid distribution into cancer tissue via organic cation transporters (OCTs). Additionally, the charged squaraine fluorophores are retained in lysosomes, providing durable intraoperative imaging in a preclinical murine model of ovarian cancer up to 24 h post-injection. OCTL14 represents a significant departure from the current bioconjugation approach of using a non-targeted fluorophore and would provide surgeons with an indispensable tool to achieve optimal resection.

ZW800-PEG: A Renal Clearable Zwitterionic Near-Infrared Fluorophore for Potential Clinical Translation.

Near-infrared (NIR) fluorescence imaging has advanced medical imaging and image-guided interventions during the past three decades. Despite tremendous advances in imaging devices, surprisingly only a few dyes are currently available in the clinic. Previous fluorophores, ZW800-1A and ZW800-1C, significantly improved the poor performance of the FDA-approved indocyanine green. However, ZW800-1A is not stable in serum and ZW800-1C induces severe stacking in aqueous media. To solve such dilemmas, ZW800-PEG was designed by introducing a flexible yet stable thiol PEG linker. ZW800-PEG shows high solubility in both aqueous and organic solvents, thus improving renal clearance with minimal binding to serum proteins during systemic circulation. The sulfide group on the meso position of the heptamethine core improves serum stability and physicochemical properties including the maximum emission wavelength shift to 800 nm, enabling the use of ZW800-PEG for image-guided interventions and augmenting photothermal therapy.

In vivo evaluation of human patellar tendon microstructure and microcirculation with diffusion MRI.

BACKGROUND: Patellar tendon (PT) microstructure integrity and microcirculation status play a crucial role in the progression of tendinopathy and tendon repair. PURPOSE: To assess the feasibility and robustness of stimulated-echo based diffusion-weighted MRI with readout-segmented echo-planar imaging (ste-RS-EPI) for noninvasive assessment of microstructure and microcirculation of human PT. STUDY TYPE: Prospective. SUBJECTS: Fifteen healthy volunteers. FIELD STRENGTH/SEQUENCE: PT diffusion tensor imaging (DTI) and intravoxel incoherent motion (IVIM) were acquired with an ste-RS-EPI protocol on a 3T MRI scanner. ASSESSMENT: Subjects were positioned with their PT at the magic angle. DTI-derived parameters including axial diffusivity (AD), radial diffusivity (RD), mean diffusivity (MD), and fractional anisotropy (FA) were estimated with b-values of 0 and 800 s/mm2 and 12 diffusion directions. IVIM-derived parameters, f p , D* × f p , V b , and D* × V b were assessed in the central-third and the outer-two thirds of the PT with b-values of 0, 20, 30, 60, 80, 120, 200, 400, and 600 s/mm2 in three orthogonal directions. STATISTICAL TESTS: Paired t-tests were used to evaluate differences in IVIM parameters between the central-third and outer-two thirds regions of the patellar tendon. Paired t-tests and within-subject coefficient of variation were used to assess the intra- and intersession reproducibility of PT DTI and IVIM parameters. RESULTS: DTI parameters for healthy PT were 1.54 ± 0.09 × 10-3 mm2 /s, 1.01 ± 0.05 × 10-3 mm2 /s, 1.18 ± 0.06 × 10-3 mm2 /s, and 0.30 ± 0.04 for AD, RD, MD, and FA, respectively. Significantly higher (P < 0.05) IVIM parameters f p and D* × f p were observed in the outer-two thirds (6.1% ± 2.4% and 95.2 ± 49.6, respectively) compared with the central-third (3.8% ± 2.3% and 48.6 ± 35.2, respectively) of the PT. DATA CONCLUSION: Diffusion MRI of PT with an ste-RS-EPI protocol is clinically feasible. Both DTI- and IVIM-derived parameters of the PT demonstrated good test-retest reproducibility and interrater reliability. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2020;51:780-790.

Differentiating Rheumatoid and Psoriatic Arthritis of the Hand: Multimodality Imaging Characteristics.

Accurate diagnosis and therapeutic intervention at an early stage is paramount for the management of rheumatoid arthritis (RA) and psoriatic arthritis (PsA), which are the two major types of inflammatory arthritis that involve the hand joints. As more disease-specific medications are developed, medication selection according to the correct diagnosis becomes more important. A delay in diagnosis and inappropriate medication selection may result in poor functional prognosis. However, clinical differentiation between RA and PsA can be challenging and may become largely dependent on imaging interpretation results. Although there is substantial overlap in the imaging findings of RA and PsA, there are differences in the affected primary target sites, reflected by the various patterns of joint involvement, and different microanatomic localization of abnormalities within a single joint in each disease. Therefore, appropriate use of various imaging modalities and accurate image interpretation add significant value to the diagnosis and treatment process. The synovio-entheseal complex is an important concept for understanding the imaging features of PsA. The authors review the different features of RA and PsA of the hands seen with various imaging modalities, including radiography, US, MRI, and dual-energy CT, with updates on the contemporary role of imaging in diagnosis and treatment. The radiologist should have sufficient knowledge to interpret imaging findings and understand the strengths and weaknesses of each modality to recommend the appropriate imaging method and differentiate both diseases accurately. ©RSNA, 2020.

Development of chronic allergic responses by dampening Bcl6-mediated suppressor activity in memory T helper 2 cells.

Mice deficient in the transcriptional repressor B-cell CLL/lymphoma 6 (Bcl6) exhibit similar T helper 2 (TH2) immune responses as patients with allergic diseases. However, the molecular mechanisms underlying Bcl6-directed regulation of TH2 cytokine genes remain unclear. We identified multiple Bcl6/STAT binding sites (BSs) in TH2 cytokine gene loci. We found that Bcl6 is modestly associated with the BSs, and it had no significant effect on cytokine production in newly differentiated TH2 cells. Contrarily, in memory TH2 (mTH2) cells derived from adaptively transferred TH2 effectors, Bcl6 outcompeted STAT5 for binding to TH2 cytokine gene loci, particularly Interleukin4 (Il4) loci, and attenuated GATA binding protein 3 (GATA3) binding to highly conserved intron enhancer regions in mTH2 cells. Bcl6 suppressed cytokine production epigenetically in mTH2 cells to negatively tune histone acetylation at TH2 cytokine gene loci, including Il4 loci. In addition, IL-33, a pro-TH2 cytokine, diminished Bcl6's association with loci to which GATA3 recruitment was inversely augmented, resulting in altered IL-4, but not IL-5 and IL-13, production in mTH2 cells but no altered production in newly differentiated TH2 cells. Use of a murine asthma model that generates high levels of pro-TH2 cytokines, such as IL-33, suggested that the suppressive function of Bcl6 in mTH2 cells is abolished in severe asthma. These findings indicate a role of the interaction between TH2-promoting factors and Bcl6 in promoting appropriate IL-4 production in mTH2 cells and suggest that chronic allergic diseases involve the TH2-promoting factor-mediated functional breakdown of Bcl6, resulting in allergy exacerbation.

Th2 cell differentiation from naive CD4+ T cells is enhanced by autocrine CC chemokines in atopic diseases.

BACKGROUND: Chemokines are involved not only in regulating leucocyte recruitment, but also in other activities. However, functions other than cell recruitment remain poorly understood. We have already shown that the production of CC chemokine ligand (CCL)17 and CCL22 by antigen-stimulated naïve CD4+  T cells was higher in asthmatic patients than in healthy controls. However, the role of these chemokines in stimulated naïve CD4+ T cells remains unclear. OBJECTIVE: To clarify the biological function of CCL17 and CCL22 on naïve CD4+ T, we examined effects of these two chemokines on naïve CD4+ T cells expressing CC chemokine receptor (CCR)4 (a receptor for CCL17 and CCL22) during differentiation of Th2 cells in asthmatic patients as allergic subjects. METHODS: Naïve CD4+ T cells were prepared from healthy controls and patients with asthma. We analysed effect of CCL17 and CCL22, and blocking their receptor on differentiation of Th2 cells. RESULTS: Production of CCL17 and CCL22 by activated naive CD4+ T cells under Th2 condition was much more in asthmatic patients than in healthy controls. Proliferation and survival of the Th2 differentiating cells and restimulation-induced IL-4 production were much greater in asthmatic patients than in healthy controls. These cell biological phenomena were inhibited by blockade of CCR4. The biological effects of exogenous CCL17 and CCL22 were apparently observed in both healthy controls and asthmatic patients. The effectiveness of these chemokines on naïve CD4+ T cells from healthy controls was stronger than those from asthmatic patients. We found that thymic stromal lymphopoietin (TSLP), a Th2 promoting chemokine, is involved in the activation of CD4+ naïve T cells via production of CCL17 and CCL22. CONCLUSIONS AND CLINICAL RELEVANCE: These data suggest that CCL17 and CCL22 produced by TSLP-primed naïve CD4+ T cells in asthma might contribute to an increase in Th2 cells via autocrine loops.

MRI biomarkers in osseous tumors.

Although radiography continues to play a critical role in osseous tumor assessment, there have been remarkable advances in cross-sectional imaging. MRI has taken a lead in this assessment due to high tissue contrast and spatial resolution, which are well suited for bone lesion assessment. More recently, although somewhat lagging other organ systems, quantitative parameters have shown promising potential as biomarkers for osseous tumors. Among these sequences are chemical shift imaging (CSI), apparent diffusion coefficient (ADC), and intravoxel incoherent motion (IVIM) from diffusion-weighted imaging (DWI), quantitative dynamic contrast enhanced (DCE)-MRI, and magnetic resonance spectroscopy (MRS). In this article, we review the background and recent roles of these quantitative MRI biomarkers for osseous tumors. Level of Evidence: 3 Technical Efficacy Stage: 3 J. MAGN. RESON. IMAGING 2019. J. Magn. Reson. Imaging 2019;50:702-718.

Abbreviated quantitative UTE imaging in anterior cruciate ligament reconstruction.

BACKGROUND: Existing ultrashort echo time magnetic resonance imaging (UTE MRI) methods require prohibitively long acquisition times (~ 20-40 min) to quantitatively assess the clinically relevant fast decay T2* component in ligaments and tendons. The purpose of this study was to evaluate the feasibility and clinical translatability of a novel abbreviated quantitative UTE MRI paradigm for monitoring graft remodeling after anterior cruciate ligament (ACL) reconstruction. METHODS: Eight patients who had Graftlink™ hamstring autograft reconstruction were recruited for this prospective study. A 3D double-echo UTE sequence at 3.0 Tesla was performed at 3- and 6-months post-surgery. An abbreviated UTE MRI paradigm was established based on numerical simulations and in vivo validation from healthy knees. This proposed approach was used to assess the T2* for fast decay component ([Formula: see text]) and bound water signal fraction (fbw) of ACL graft in regions of interest drawn by a radiologist. RESULTS: Compared to the conventional bi-exponential model, the abbreviated UTE MRI paradigm achieved low relative estimation bias for [Formula: see text] and fbw over a range of clinically relevant values for ACL grafts. A decrease in [Formula: see text] of the intra-articular graft was observed in 7 of the 8 ACL reconstruction patients from 3- to 6-months (- 0.11 ± 0.16 ms, P = 0.10). Increases in [Formula: see text] and fbw from 3- to 6-months were observed in the tibial intra-bone graft ([Formula: see text]: 0.19 ± 0.18 ms, P < 0.05; Δfbw: 4% ± 4%, P < 0.05). Lower [Formula: see text] (- 0.09 ± 0.11 ms, P < 0.05) was observed at 3-months when comparing the intra-bone graft to the graft/bone interface in the femoral tunnel. The same comparisons at the 6-months also yielded relatively lower [Formula: see text] (- 0.09 ± 0.12 ms, P < 0.05). CONCLUSION: The proposed abbreviated 3D UTE MRI paradigm is capable of assessing the ACL graft remodeling process in a clinically translatable acquisition time. Longitudinal changes in [Formula: see text] and fbw of the ACL graft were observed.

Spatially distinct and metabolically active membrane domain in mycobacteria.

Protected from host immune attack and antibiotic penetration by their unique cell envelope, mycobacterial pathogens cause devastating human diseases such as tuberculosis. Seamless coordination of cell growth with cell envelope elongation at the pole maintains this barrier. Unraveling this spatiotemporal regulation is a potential strategy for controlling mycobacterial infections. Our biochemical analysis previously revealed two functionally distinct membrane fractions in Mycobacterium smegmatis cell lysates: plasma membrane tightly associated with the cell wall (PM-CW) and a distinct fraction of pure membrane free of cell wall components (PMf). To provide further insight into the functions of these membrane fractions, we took the approach of comparative proteomics and identified more than 300 proteins specifically associated with the PMf, including essential enzymes involved in cell envelope synthesis such as a mannosyltransferase, Ppm1, and a galactosyltransferase, GlfT2. Furthermore, comparative lipidomics revealed the distinct lipid composition of the PMf, with specific association of key cell envelope biosynthetic precursors. Live-imaging fluorescence microscopy visualized the PMf as patches of membrane spatially distinct from the PM-CW and notably enriched in the pole of the growing cells. Taken together, our study provides the basis for assigning the PMf as a spatiotemporally distinct and metabolically active membrane domain involved in cell envelope biogenesis.

Correlation of bone marrow cellularity and metabolic activity in healthy volunteers with simultaneous PET/MR imaging.

OBJECTIVE: To evaluate the correlation between bone marrow cellularity (BMC) and metabolic activity in healthy subjects and to see whether yellow marrow is indeed metabolically quiescent. Because metabolic activity can be assumed to reflect vascularity, we assessed the relationship between regional metabolic activity and geographic frequency of metastases as noted in the literature. MATERIALS AND METHODS: Two hundred and twenty locations (ten in each side of the pelvis and proximal femur) were evaluated in 11 consecutive healthy volunteers with simultaneous PET/MR. BMC was calculated through precise water-fat fraction quantification with a 6-echo gradient echo. We analyzed correlations between cellularity and SUVr, age, and R2*. We also looked at the relation between our results and the reported prevalence of metastases. RESULTS: There was moderate but statistically significant correlation between BMC and metabolic activity (r = 0.636, p < 0.0001). Interestingly, the iliac and sacrum had higher metabolic activity relative to cellularity, whereas the femoral neck and lesser trochanter showed lower SUVr than other regions with the similar cellularity. The relatively lower metabolic status of the femoral neck conflicted with its reported high frequency of metastasis. Excluding regions with almost no remaining red marrow, cellularity showed inverse relationship with age (r = 0.476, p < 0.0001) and direct relationship with R2* (r = 0.532, p < 0.0010). CONCLUSIONS: Metabolic activity of bone marrow was largely dependent on BMC while yellow marrow seems metabolically quiescent. The discrepancy between the assumed vascularity as determined by metabolic activity and reported sites of metastasis suggested that the process of bone metastasis may not depend entirely on vascularity.

Target identification of hepcidin production inhibitors by a combination of chemical proteomics and radioactive compound binding assay.

Hepcidin is a peptide hormone and has emerged as the central molecule regulating systemic iron homeostasis. Hepcidin inhibition could be a strategy for treating anemia of chronic disease. We previously reported the discovery of DS79182026, a new inhibitor of hepcidin production, from phenotypic screening using the human hepatocyte HepG2 cell line. In this study, we utilized a combination of affinity purification-based chemical proteomics and radioactive compound binding assay, and identified several candidate proteins. Purified recombinant proteins were subjected to radioactive compound binding assays for validation, and ALK2 and ALK3 demonstrated specific binding to the compound. Since ALK2 is known to be related to hepcidin production, we focused on ALK2 and found that its knockdown decreased hepcidin expression; we also found a strong correlation (R = 0.920) between pharmacological activity and compound affinity to ALK2. These results indicate that ALK2 is the primary target protein of our new hepcidin production inhibitors.