Hypoxia activates SREBP2 through Golgi disassembly in bone marrow-derived monocytes for enhanced tumor growth.

Bone marrow-derived cells (BMDCs) infiltrate hypoxic tumors at a pre-angiogenic state and differentiate into mature macrophages, thereby inducing pro-tumorigenic immunity. A critical factor regulating this differentiation is activation of SREBP2-a well-known transcription factor participating in tumorigenesis progression-through unknown cellular mechanisms. Here, we show that hypoxia-induced Golgi disassembly and Golgi-ER fusion in monocytic myeloid cells result in nuclear translocation and activation of SREBP2 in a SCAP-independent manner. Notably, hypoxia-induced SREBP2 activation was only observed in an immature lineage of bone marrow-derived cells. Single-cell RNA-seq analysis revealed that SREBP2-mediated cholesterol biosynthesis was upregulated in HSCs and monocytes but not in macrophages in the hypoxic bone marrow niche. Moreover, inhibition of cholesterol biosynthesis impaired tumor growth through suppression of pro-tumorigenic immunity and angiogenesis. Thus, our findings indicate that Golgi-ER fusion regulates SREBP2-mediated metabolic alteration in lineage-specific BMDCs under hypoxia for tumor progression.

[Endovascular Repair of Aortic Injury Caused by Esophageal Foreign Body:Report of a Case].

A 51-year-old man visited to our hospital because of chest discomfort and hematemesis. He was diagnosed with Mallory-Weiss syndrome and followed in outpatient clinic. One week later, he visited our hospital again for fever and discomfort. Chest computed tomography (CT) showed a foreign body perforated in the mediastinum in the upper esophagus, and he was urgently hospitalized for surgical removal of esophageal foreign body. Before surgery he vomited the esophageal foreign body with a lot of blood. Hematemesis was stopped spontaneously and contrast-enhanced CT revealed a pseudoaneurysm in the distal aortic arch, so thoracic endovascular aortic repair (TEVAR) was performed to prevent rupture. Esophageal endoscopy found that the site of esophageal injury healed spontaneously, so the patient was followed conservatively with antibiotics. He was discharged on postoperative day 18 uneventfully. TEVAR was an effective treatment for aortic injury caused by esophageal foreign body in our case.

Pretreatment periodontitis is predictive of a poorer prognosis after esophagectomy for esophageal cancer.

BACKGROUND: Poor oral health is an independent risk factor for upper-aerodigestive tract cancers, including esophageal cancer. Several studies have investigated short-term outcomes after esophagectomy and the impact of periodontal disease, but few have examined the impact of periodontal disease on long-term outcomes. The purpose of this study was to investigate the rate of periodontitis among esophagectomy patients and the prognostic value of periodontitis and its effect on prognosis after esophagectomy. METHODS: A total of 508 patients who underwent esophagectomy received oral health care from a dentist before cancer treatment at Akita University Hospital between January 2009 and December 2021. We assessed the presence and severity of the patients' periodontitis and divided them into no-periodontitis, mild periodontitis, severe periodontitis and edentulous jaw groups. We then assessed 10-year overall survival (OS) and disease-specific survival (DSS) and determined whether periodontitis was an independent prognostic factor affecting OS and DSS. RESULTS: We found that 101 (19.9%) patients had no periodontitis, 207 (40.8%) had mild periodontitis, 176 (34.6%) had severe periodontitis requiring tooth extraction, and 24 (4.7%) had edentulous jaw. Both OS and DSS were significantly poorer in the periodontitis than no-periodontitis group (p < 0.001). In detail, the edentulous jaw group had the poorest prognosis (p < 0.001). Multivariate analysis showed that periodontitis was an independent risk factor affecting OS and DSS. CONCLUSION: Esophageal cancer patients had a high prevalence of periodontitis. Moreover, the presence of periodontitis and severity of periodontitis are independent risk factors contributing to a poorer prognosis after esophagectomy.

Mitochondrial one-carbon metabolic enzyme MTHFD2 facilitates mammary gland development during pregnancy.

Mitochondrial one-carbon metabolism is crucial for embryonic development and tumorigenesis, as it supplies one-carbon units necessary for nucleotide synthesis and rapid cell proliferation. However, its contribution to adult tissue homeostasis remains largely unknown. To examine its role in adult tissue homeostasis, we specifically investigated mammary gland development during pregnancy, as it involves heightened cell proliferation. We discovered that MTHFD2, a mitochondrial one-carbon metabolic enzyme, is expressed in both luminal and basal/myoepithelial cell layers, with upregulated expression during pregnancy. Using the mouse mammary tumor virus (MMTV)-Cre recombinase system, we generated mice with a specific mutation of Mthfd2 in mammary epithelial cells. While the mutant mice were capable of properly nurturing their offspring, the pregnancy-induced expansion of mammary glands was significantly delayed. This indicates that MTHFD2 contributes to the rapid development of mammary glands during pregnancy. Our findings shed light on the role of mitochondrial one-carbon metabolism in facilitating rapid cell proliferation, even in the context of the adult tissue homeostasis.

IFN/STAT signaling controls tumorigenesis and the drug response in colorectal cancer.

Colorectal cancer (CRC) is caused by genetic alterations, and comprehensive sequence analyses have revealed the mutation landscapes. In addition to somatic changes, genetic variations are considered important factors contributing to tumor development; however, our knowledge on this subject is limited. Familial adenomatous polyposis coli (FAP) is an autosomal-dominant inherited disease caused by germline mutations in the adenomatous polyposis coli (APC) gene. FAP patients are classified into two major groups based on clinical manifestations: classical FAP (CFAP) and attenuated FAP (AFAP). In this study, we established 42 organoids from three CFAP patients and two AFAP patients. Comprehensive gene expression analysis demonstrated a close association between IFN/STAT signaling and the phenotypic features of FAP patients. Genetic disruption of Stat1 in the mouse model of FAP reduced tumor formation, demonstrating that the IFN/STAT pathway is causally associated with the tumor-forming potential of APC-deficient tumors. Mechanistically, STAT1 is downstream target of KRAS and is phosphorylated by its activating mutations. We found that enhanced IFN/STAT signaling in CFAP conferred resistance to MEK inhibitors. These findings reveal the crosstalk between RAS signaling and IFN/STAT signaling, which contributes to the tumor-forming potential and drug response. These results offer a rationale for targeting of IFN/STAT signaling and for the stratification of CRC patients.

Folding pathways of NuG2-a designed mutant of protein G-using relaxation mode analysis.

Dynamic analysis methods are important for analyzing long simulations such as folding simulations. Relaxation mode analysis, which approximately extracts slow modes and rates, has been applied in molecular dynamics (MD) simulations of protein systems. Previously, we showed that slow modes are suitable for analyzing simulations in which large conformational changes occur. Here, we applied relaxation mode analysis to folding simulations of a designed mutant of protein G, NuG2, to investigate its folding pathways. The folding simulations of NuG2 were previously performed for this mutant with Anton. In the present study, the free energy surfaces were calculated by projecting the coordinates on the axis of the slow relaxation modes obtained from relaxation mode analysis. We classified various characteristic states such as native, nativelike, intermediate, and random states and clarified two main folding pathways. In the early folding process, the first and second ß strands formed an N-terminal ß-sheet. After the early folding process, the fourth ß strand formed along the first ß strand in the same or opposite direction as the native structure; two characteristic intermediate states were identified. Finally, the intermediate structures folded to the native structure in the folding process. Relaxation mode analysis can be applied to folding simulations of complex proteins to investigate their folding processes.

Identification of slow relaxation modes in a protein trimer via positive definite relaxation mode analysis.

Recently, dynamic analysis methods in signal processing have been applied to the analysis of molecular dynamics (MD) trajectories of biopolymers. In the context of a relaxation mode analysis (RMA) method, based on statistical physics, it is explained why the signal-processing methods work well for the simulation trajectories of biopolymers. A distinctive difference between the RMA method and the signal-processing methods is the introduction of an additional parameter, called an evolution time parameter. This parameter enables us to better estimate the relaxation modes and rates, although it increases computational difficulty. In this paper, we propose a simple and effective extension of the RMA method, which is referred to as the positive definite RMA method, to introduce the evolution time parameter robustly. In this method, an eigenvalue problem for the time correlation matrix of physical quantities relevant to slow relaxation in a system is first solved to find the subspace in which the matrix is numerically positive definite. Then, we implement the RMA method in the subspace. We apply the method to the analysis of a 3-µs MD trajectory of a heterotrimer of an erythropoietin protein and two of its receptor proteins, and we demonstrate the effectiveness of the method.

Multipoint segmental repulsive potential for entangled polymer simulations with dissipative particle dynamics.

A model is developed for simulating entangled polymers by dissipative particle dynamics (DPD) using the segmental repulsive potential (SRP). In contrast to previous SRP models that define a single-point interaction on each bond, the proposed SRP model applies a dynamically adjustable multipoint on the bond. Previous SRP models could not reproduce the equilibrium properties of Groot and Warren's original DPD model [R. D. Groot and P. B. Warren, J. Chem. Phys. 107, 4423 (1997)] because the introduction of a single SRP induces a large excluded volume, whereas, the proposed multipoint SRP (MP-SRP) introduces a cylindrical effective excluded bond volume. We demonstrate that our MP-SRP model exhibits equilibrium properties similar to those of the original DPD polymers. The MP-SRP model parameters are determined by monitoring the number of topology violations, thermodynamic properties, and the polymer internal structure. We examine two typical DPD polymers with different bond-length distributions; one of them was used in the modified SRP model by Sirk et al. [J. Chem. Phys. 136, 134903 (2012)], whereas the other was used in the original DPD model. We demonstrate that for both polymers, the proposed MP-SRP model captures the entangled behaviors of a polymer melt naturally, by calculating the slowest relaxation time of a chain in the melt and the shear relaxation modulus. The results indicate that the proposed MP-SRP model can be applied to a variety of DPD polymers.

[Structural Deterioration of a Bovine Pericardial Valve in a Tricuspid Position 14 Years Postoperatively;Report of a Case].

Although nonstructural dysfunction of a bioprosthesis caused by pannus formation or native valve attachment has been well described, structural valve deterioration( SVD) caused by calcification or tear of a bioprosthesis, especially a bovine pericardial valve, is very rare in the tricuspid position. We report a case of redo tricuspid valve surgery for SVD 14 years after tricuspid valve replacement( TVR) using a Carpentier-Edwards Perimount (CEP) pericardial valve. A 71-year-old woman was referred to our hospital because of exertional dyspnea and pre-syncope. She had undergone mitral valve replacement with a St. Jude Medical mechanical valve and TVR with a CEP pericardial valve 14 years previously. Transthoracic echocardiography revealed tricuspid valve stenosis with a mean trans-tricuspid valve pressure gradient (TVPG) of 7.3 mmHg. Redo TVR using a CEP Magna Mitral Ease valve was performed under cardiac arrest. Severe calcification was observed on the ventricular side of the leaflets of the explanted valve. The mean TVPG decreased to 3.2 mmHg after surgery, and the patient's postoperative course was uneventful.

Severe tricuspid regurgitation after mitral valve surgery: the risk factors and results of the aggressive application of prophylactic tricuspid valve repair.

PURPOSE: This study aimed to examine the risk factors for severe postoperative tricuspid regurgitation (TR) in patients undergoing mitral valve surgery. We also studied the effects of prophylactic tricuspid valve repair (TVR) on severe postoperative TR. METHODS: We retrospectively studied 125 patients without severe TR who underwent mitral valve surgery from 1987 to 2006. Patients did not undergo TVR before 1998 (the early period, n = 54). In 1998 (the late period, n = 71), patients with a preoperative tricuspid annular diameter of ≥35 mm underwent TVR using an annuloplasty ring (n = 52). RESULTS: In the analysis of the early period, the rates of freedom from severe TR at 10 and 20 years after surgery were 76 and 59 %, respectively. A multivariate analysis identified moderate preoperative TR as a significant risk factor for severe TR. In the late period, none of the 52 patients who underwent TVR developed severe TR. However, 4/19 patients who did not undergo TVR developed severe TR, and all of these four patients had a preoperative tricuspid annular diameter of ≤35 mm. CONCLUSIONS: Moderate preoperative TR is a significant risk factor for severe postoperative TR in patients undergoing mitral valve surgery. The aggressive application of TVR can prevent severe postoperative TR; however, tricuspid annular dilatation might not be a good indicator for TVR.

Esophageal Cancer Patients Have a High Incidence of Severe Periodontitis and Preoperative Dental Care Reduces the Likelihood of Severe Pneumonia after Esophagectomy.

BACKGROUND: Poor oral health is a risk factor for causing upper aerodigestive tract tumors, including esophageal cancer. Our aim was to determine the periodontitis rate in our cohort of esophageal cancer patients. We also analyzed whether preoperative dental examination and care reduces the likelihood of severe pneumonia after esophagectomy. STUDY DESIGN: Between 2003 and 2014, 529 esophageal cancer patients received esophagectomy at Akita University Hospital. We studied 232 patients who had preoperative dental examinations and care (dental care group) retrospectively and assessed the severity of their periodontitis. The dental care group was compared to 297 patients who did not have preoperative dental care (control group) with respect to the incidence of severe pneumonia after esophagectomy. RESULTS: Ninety-one patients (39.2%) in the dental care group were diagnosed with slight periodontitis and 69 (29.7%) were diagnosed with severe periodontitis. Among all the patients, 69 patients (13.0%) were diagnosed with grade 3B postoperative severe pneumonia. The dental care group had a significantly lower incidence of severe pneumonia than the control group. Moreover, multivariable logistic regression analysis revealed that anastomotic leakage, preoperative dental care, gender and %VC were correlated significantly with the occurrence of postoperative severe pneumonia. CONCLUSION: Preoperative dental examination and care by a dentist are essential to reduce the likelihood of postoperative severe pneumonia in esophageal cancer patients.

[Surgical Technique for Massive Shunt after Repair of Post-infarction Ventricular Perforation].

We report a case of large anterior septal perforation (40×20 mm) immediately following repair of ventricular septal perforation( 9×9 mm) with the infarction exclusion technique. The large perforation was successfully repaired through a left ventriculotomy with a combined double patch/cone-shaped patch technique. This technique can be effective not only in cases of large laceration of ventricular septum as a consequence of inappropriate repair but also of large septal perforation with extensive fragility of the septal myocardium.

[Three Mitral Valve Operations in a Patient with Trousseau Syndrome and Nonbacterial Thrombotic Endocarditis Caused by Ovarian Cancer].

A 52-year-old woman was admitted to our hospital for acute right hemi-paresis, left homonymous hemianopia, and fever. Magnetic resonance imaging of the brain showed multiple cerebral infarctions and transesophageal echocardiography (TEE) revealed a vegetation on the posterior leaflet of her mitral valve. Mitral valve repair was performed under a diagnosis of infective endocarditis (IE). Further multiple cerebral infarctions occurred on the 11th postoperative day, resulting in left hemiplegia and dysarthria. TEE revealed vegetations on her mitral valve and mitral valve replacement (MVR) was performed. Microscopic examination of the resected valve showed mild lymphocytic infiltration, but no bacterial or fungal organisms were detected. On the 66th day after the initial surgery, she developed deep vein thrombosis and acute pulmonary embolism. Abdominal computed tomography showed a huge ovarian tumor, and TEE demonstrated vegetations on the left atrial wall, the aortic valve, and the mechanical valve immobilizing one of the leaflets. The patient was finally diagnosed as having Trousseau syndrome caused by an ovarian tumor and non-bacterial thrombotic endocarditis( NBTE). Three months after the initial operation, redo MVR was performed and aortic valve vegetations were removed. Four days later, the ovarian cancer was resected. Her postoperative course was uneventful and she was discharged on foot on the 143rd day after the initial operation. NBTE caused by malignancy is rare but must be considered when managing endocarditis.

Relaxation mode analysis and Markov state relaxation mode analysis for chignolin in aqueous solution near a transition temperature.

It is important to extract reaction coordinates or order parameters from protein simulations in order to investigate the local minimum-energy states and the transitions between them. The most popular method to obtain such data is principal component analysis, which extracts modes of large conformational fluctuations around an average structure. We recently applied relaxation mode analysis for protein systems, which approximately estimates the slow relaxation modes and times from a simulation and enables investigations of the dynamic properties underlying the structural fluctuations of proteins. In this study, we apply this relaxation mode analysis to extract reaction coordinates for a system in which there are large conformational changes such as those commonly observed in protein folding/unfolding. We performed a 750-ns simulation of chignolin protein near its folding transition temperature and observed many transitions between the most stable, misfolded, intermediate, and unfolded states. We then applied principal component analysis and relaxation mode analysis to the system. In the relaxation mode analysis, we could automatically extract good reaction coordinates. The free-energy surfaces provide a clearer understanding of the transitions not only between local minimum-energy states but also between the folded and unfolded states, even though the simulation involved large conformational changes. Moreover, we propose a new analysis method called Markov state relaxation mode analysis. We applied the new method to states with slow relaxation, which are defined by the free-energy surface obtained in the relaxation mode analysis. Finally, the relaxation times of the states obtained with a simple Markov state model and the proposed Markov state relaxation mode analysis are compared and discussed.

[Surgical Treatment of Prosthetic Valve Endocarditis; Tips of Complete Resection of Infective Tissue and Valve Replacement].

Fifteen consecutive prosthetic valve endocarditis (PVE) patients were operated from March 2009 to September 2014. The average age of patients was 68 years ( range 49 to 82) and 7 patients were male. The interval between initial surgery and reoperation was 62.4 months(range 2.6 to 340.9). Seven of these cases(47%) developed PVE within the 1st year after surgery were defined as early PVE. All microorganisms isolated from blood cultures in early PVE were Staphylococcus species. Generally, the infective prosthetic valve was removed 1st, then all infective tissues were excised from the periannular cavity. A new prosthetic valve was replaced in supra-annular fashion. One patient who had a severe discontinuity between the most part of left ventricle and aorta necessitated a root replacement. One patient in aortic PVE, needed an additional patch-plasty of anterior mitral leaflet. The mean cardiopulmonary bypass and aortic clamping times were 250 minutes( range 132 to 426) and 165 minutes( range 117 to 309), respectively. Four patients needed permanent pacemaker implanted for complete A-V block. Five patients had transient acute renal failure, and 1 required dialysis could be weaned at 40 post operative day. Average postoperative hospital stay was 39 days (range 21 to 108), and the operative mortality was 0%. The postoperative follow up was 3.1 years( range 0.6 to 6.0), all patients were doing well without re-infection and heart failure except 1 patient died by non-cardiac disease.

Synergistic effect of zoledronate and compressive force suppresses proliferation and differentiation of human gingival fibroblasts.

We investigated the effects of zoledronate (ZA) and compressive force, separately and in combination, on the proliferation and differentiation of human gingival fibroblasts (HGFs) to verify the mechanism underlying medication-related osteonecrosis of the jaw (MRONJ). The addition of 100 µM ZA markedly inhibited cell proliferation. Expression of type I collagen, fibroblast growth factor 2, and connective tissue growth factor genes, was decreased by ZA and compressive force. Similar results were observed for collagen expression by using Sirius red staining. These results, together with clinical findings that MRONJ is more common in cases with excessive mechanical stress on the oral mucosa, suggest that bisphosphonates such as ZA and mechanical stress may act in conjunction as risk factors for the development of MRONJ by affecting homeostasis of the oral mucosal tissues, including HGFs.

The role of CRMP4 in LPS-induced neuroinflammation.

Neuroinflammation has been gaining attention as one of the potential causes of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis in recent years. The suppression of excessive proinflammatory responses is expected to be a target for the treatment and prevention of neurodegenerative diseases. Collapsin response mediator protein 4 (CRMP4) is involved in cytoskeleton-associated axonal guidance in the developing brain. Recently, the involvement of CRMP4 in several pathological conditions, including inflammation induced by lipopolysaccharide (LPS), a widely used inflammatory molecule, has been reported. However, the role of CRMP4 in LPS-induced inflammation in vivo remains largely unknown. In this study, we generated microglia-specific CRMP4 knockout mice for the first time and examined the role of CRMP4 in an LPS-induced brain inflammation model. We found that microglia after LPS injection in substantia nigra was significantly reduced in Crmp4-/- mice compared to Crmp4+/+mice. The increased expression of IL-10 in striatum samples was downregulated in Crmp4-/- mice. A significant reduction in Iba1 expression was also observed in microglia-specific Crmp4 knockout mice compared with that in control mice. In contrast, the expression of IL-10 did not change in these mice, whereas arginase 1 (Arg1) expression was significantly suppressed. These results demonstrate the involvement of CRMP4 in LPS-induced inflammation in vivo, that CRMP4 suppresses microglial proliferation in a cell-autonomous manner.

Chromatin profiling identifies chondrocyte-specific Sox9 enhancers important for skeletal development.

The transcription factor SRY-related HMG box 9 (Sox9) is essential for chondrogenesis. Mutations in and around SOX9 cause campomelic dysplasia (CD) characterized by skeletal malformations. Although the function of Sox9 in this context is well studied, the mechanisms that regulate Sox9 expression in chondrocytes remain to be elucidated. Here, we have used genome-wide profiling to identify 2 Sox9 enhancers located in a proximal breakpoint cluster responsible for CD. Enhancer activity of E308 (located 308 kb 5' upstream) and E160 (located 160 kb 5' upstream) correlated with Sox9 expression levels, and both enhancers showed a synergistic effect in vitro. While single deletions in mice had no apparent effect, simultaneous deletion of both E308 and E160 caused a dwarf phenotype, concomitant with a reduction of Sox9 expression in chondrocytes. Moreover, bone morphogenetic protein 2-dependent chondrocyte differentiation of limb bud mesenchymal cells was severely attenuated in E308/E160 deletion mice. Finally, we found that an open chromatin region upstream of the Sox9 gene was reorganized in the E308/E160 deletion mice to partially compensate for the loss of E308 and E160. In conclusion, our findings reveal a mechanism of Sox9 gene regulation in chondrocytes that might aid in our understanding of the pathophysiology of skeletal disorders.

Layered perovskite oxide: a reversible air electrode for oxygen evolution/reduction in rechargeable metal-air batteries.

For the development of a rechargeable metal-air battery, which is expected to become one of the most widely used batteries in the future, slow kinetics of discharging and charging reactions at the air electrode, i.e., oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), respectively, are the most critical problems. Here we report that Ruddlesden-Popper-type layered perovskite, RP-LaSr3Fe3O10 (n = 3), functions as a reversible air electrode catalyst for both ORR and OER at an equilibrium potential of 1.23 V with almost no overpotentials. The function of RP-LaSr3Fe3O10 as an ORR catalyst was confirmed by using an alkaline fuel cell composed of Pd/LaSr3Fe3O10-2x(OH)2x·H2O/RP-LaSr3Fe3O10 as an open circuit voltage (OCV) of 1.23 V was obtained. RP-LaSr3Fe3O10 also catalyzed OER at an equilibrium potential of 1.23 V with almost no overpotentials. Reversible ORR and OER are achieved because of the easily removable oxygen present in RP-LaSr3Fe3O10. Thus, RP-LaSr3Fe3O10 minimizes efficiency losses caused by reactions during charging and discharging at the air electrode and can be considered to be the ORR/OER electrocatalyst for rechargeable metal-air batteries.