Osteoblast Lineage Cell-derived Sema3A Regulates Bone Homeostasis Independently of Androgens.

Semaphorin 3A (Sema3A) coordinates bone resorption and formation under the control of estrogen signaling. However, the contribution of osteoblast lineage cell-derived Sema3A to vertebral homeostasis has remained unclear. Moreover, it is unknown whether androgen signaling is involved in Sema3A expression in osteoblast lineage cells. In this study, we show that osteoblast lineage cell-derived Sema3A plays a key role in bone homeostasis independent of androgen signaling. Sema3a deletion with Sp7-Cre did not alter the trabecular bone mass in lumbar vertebrae, along with there being no significant difference in Sema3a mRNA expression. In contrast, osteoblast lineage cell-specific deletion of Sema3A with BGLAP-Cre led to decreased bone volume in both long bones and lumbar vertebrae. In addition, osteoblast lineage cell-derived Sema3A was not involved in orchidectomy-induced bone loss because androgen deficiency did not affect Sema3A protein expression. Thus, these results indicate that Sema3A derived from osteoblast lineage cells acts as an osteoprotective factor, even in vertebrae, and its expression is controlled in an androgen-independent manner.

Combination therapy with remdesivir and immunomodulators improves respiratory status in COVID-19: A retrospective study.

Immunomodulators (tocilizumab/baricitinib) improve outcomes of coronavirus disease 2019 (COVID-19) patients, but the synergistic effect of remdesivir is unknown. The effect of combination therapy with remdesivir, immunomodulators, and standard treatment in COVID-19 patients was investigated. This retrospective, single-center study included COVID-19 patients who were treated with tocilizumab or baricitinib. The severity of respiratory status in the two groups on Days 14 and 28 and the duration to respiratory recovery in both groups were compared, and the effect of remdesivir use on respiratory status was examined in a multivariate analysis. Ninety-eight patients received tocilizumab or baricitinib; among them, 72 used remdesivir (remdesivir group) and 26 did not (control group). The remdesivir group achieved faster respiratory recovery than the control group (median 11 vs. 21 days, p = 0.033), faster weaning from supplemental oxygen (hazard ratio [HR]: 2.54, 95% confidence interval [CI]: 1.14-5.66, p = 0.021). Age, body mass index, diabetes mellitus, and time from onset to oxygen administration were independent prognostic factors. The remdesivir group achieved better severity level at Days 14 and 28 (p = 0.033 and 0.003, respectively) and greater improvement from baseline severity (p = 0.047 and 0.018, respectively). Remdesivir combination therapy did not prolong survival (HR: 0.31, 95% CI: 0.04-2.16, p = 0.23). Among severely ill COVID-19 patients who received immunomodulator, remdesivir contributed to a shorter respiratory recovery time and better respiratory status at Days 14 and 28. Concomitant remdesivir with immunomodulators and standard treatment may provide additional benefit in improving respiratory status of COVID-19 patients.

Induced Radionuclides and Their Activity Concentration in Gel Dosimeters Irradiated by Carbon Ion Beam.

Radioactivity was measured in a micellar gel dosimeter, a polymer gel dosimeter, and water was irradiated by carbon ion beams at various beam energy conditions. Monte Carlo simulation was also performed to estimate the radioactivity. Short-lived positron-emitting nuclides were observed immediately after irradiation, but they decayed rapidly into the background. At 24 h post-irradiation, the dominant measured radioactivity was of 7Be. The simulation also showed minor activity of 24Na and 3H; however, they were not experimentally observed. The measured radioactivity was independent of the type of gel dosimeter under all irradiation conditions, suggesting that the radioactivity was induced by the interaction of carbon ions with water (the main component of the gel dosimeters). The ratio between the simulated and measured radioactivity was within 0.9-1.5. The activity concentration of 7Be was found to be less than 1/10 of the value derived using the exemption concept proposed by the International Atomic Energy Agency. This result should be applicable to irradiated gel dosimeters containing mainly water and 0-4 wt.% C and 0-1.7 wt.% N.

Inflammation and Bone Metabolism in Rheumatoid Arthritis: Molecular Mechanisms of Joint Destruction and Pharmacological Treatments.

Rheumatoid arthritis (RA) is an inflammatory disease characterized by a variety of symptoms and pathologies often presenting with polyarthritis. The primary symptom in the initial stage is joint swelling due to synovitis. With disease progression, cartilage and bone are affected to cause joint deformities. Advanced osteoarticular destruction and deformation can cause irreversible physical disabilities. Physical disabilities not only deteriorate patients' quality of life but also have substantial medical economic effects on society. Therefore, prevention of the progression of osteoarticular destruction and deformation is an important task. Recent studies have progressively improved our understanding of the molecular mechanism by which synovitis caused by immune disorders results in activation of osteoclasts; activated osteoclasts in turn cause bone destruction and para-articular osteoporosis. In this paper, we review the mechanisms of bone metabolism under physiological and RA conditions, and we describe the effects of therapeutic intervention against RA on bone.

DCAF11 Supports Targeted Protein Degradation by Electrophilic Proteolysis-Targeting Chimeras.

Ligand-induced protein degradation has emerged as a compelling approach to promote the targeted elimination of proteins from cells by directing these proteins to the ubiquitin-proteasome machinery. So far, only a limited number of E3 ligases have been found to support ligand-induced protein degradation, reflecting a dearth of E3-binding compounds for proteolysis-targeting chimera (PROTAC) design. Here, we describe a functional screening strategy performed with a focused library of candidate electrophilic PROTACs to discover bifunctional compounds that degrade proteins in human cells by covalently engaging E3 ligases. Mechanistic studies revealed that the electrophilic PROTACs act through modifying specific cysteines in DCAF11, a poorly characterized E3 ligase substrate adaptor. We further show that DCAF11-directed electrophilic PROTACs can degrade multiple endogenous proteins, including FBKP12 and the androgen receptor, in human prostate cancer cells. Our findings designate DCAF11 as an E3 ligase capable of supporting ligand-induced protein degradation via electrophilic PROTACs.

Successful management of a patient with active Cushing's disease complicated with coronavirus disease 2019 (COVID-19) pneumonia.

We provide the details of the successful management of a patient with active Cushing's disease complicated with coronavirus disease 2019 (COVID-19) pneumonia. The patient was a 27-year-old Japanese female healthcare worker who was scheduled to undergo pituitary surgery for Cushing's disease. She had been in close contact with an undiagnosed patient infected with COVID-19 and then developed COVID-19 pneumonia. Despite a lack of known risk factors associated with severe COVID-19 infection, the patient's dyspnea worsened and her respiratory condition deteriorated, as indicated by the need for 7 L/min oxygen supply by mask to maintain her oxygen saturation at >90%. Medical treatment was initiated to control hypercortisolism by the 'block and replace' regimen using steroidogenesis inhibitors and hydrocortisone. The COVID-19 pneumonia improved with multi-modal treatment including antiviral therapy. One month later, after a negative severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) test result and with appropriate protection against virus transmission to medical staff in the operating room and daily medical care nurses, trans-sphenoidal surgery was performed by our highly experienced pituitary surgeon. One month after the surgery, the patient's basal ACTH and cortisol levels and urinary free cortisol were all under the detection limit. Surgical remission was expected. Since hypercortisolism due to active Cushing's disease may worsen a COVID-19 infection, multi-disciplinary management that includes appropriate and prompt treatment strategies is mandatory in such cases.

Proposal of COVID-19 Clinical Risk Score for the management of suspected COVID-19 cases: a case control study.

BACKGROUND: No clinical scoring system has yet been established to estimate the likelihood of coronavirus disease (COVID-19) and determine the suitability of diagnostic testing in suspected COVID-19 patients. METHODS: This was a single-center, retrospective, observational study of patients with suspected COVID-19 and confirmed COVID-19. Patient background, clinical course, laboratory and computed tomography (CT) findings, and the presence of alternative diagnoses were evaluated. Clinical risk scores were developed based on clinical differences between patients with and without COVID-19. RESULTS: Among 110 patients suspected of having COVID-19, 60.9% underwent polymerase chain reaction (PCR) testing based on the judgment of physicians. Two patients were found to have COVID-19. The clinical characteristics of 108 non-COVID-19 patients were compared with those of 23 confirmed COVID-19 patients. Patients with COVID-19 were more likely to have a history of high-risk exposures and an abnormal sense of taste and smell. The COVID-19 group had significantly higher rates of subnormal white blood cell counts, lower eosinophil counts, and lower procalcitonin levels than the non-COVID-19 group. When blood test results, CT findings, and the presence of alternative diagnoses were scored on an 11-point scale (i.e., "COVID-19 Clinical Risk Score"), the COVID-19 group scored significantly higher than the non-COVID-19 group, more than four points in the COVID-19 group. All non-COVID patients who did not undergo PCR had a score of 4 or less. CONCLUSIONS: The COVID-19 Clinical Risk Score may enable the risk classification of patients suspected of having COVID-19 and can help in decision-making in clinical practice, including appropriateness of diagnostic testing. Further studies and prospective validation with an increased sample size are required.

[Preservation of the Spinal Perfusion Artery during Descending Thoracic and Thoracoabdominal Aortic Surgery].

This is a 3-case report of successful descending thoracic and thoracoabdominal aortic surgery by preserving the spinal perfusion artery (SPA) identified preoperatively. In Case 1, an 85-year-old woman, computed tomography (CT) showed Crawford type Ⅴ thoracoabdominal aortic aneurysm (TAAA:60 mm) and a SPA originated from L2. In Case 2, a 76-year-old man, CT revealed type Ⅳ TAAA( 58 mm) and a SPA originated from Th11. In Case 3, a 74-year-old man, CT detected an infectious pseudoaneurysm(44 mm) in the descending thoracic aorta with 2 SPAs originating from Th10 and L2. The ranges of graft replacement were Th7-Th12, Th12-L4, and Th8-Th10, respectively, while preserving all SPAs. All patients recovered well without postoperative neurological deficits. Although the protective effect of the SPA preservation against the spinal cord ischemia is still controversial, preoperative identification of the SPA was useful for planning a surgical strategy for descending thoracic and thoracoabdominal aortic repair surgery.

An Activity-Guided Map of Electrophile-Cysteine Interactions in Primary Human T Cells.

Electrophilic compounds originating from nature or chemical synthesis have profound effects on immune cells. These compounds are thought to act by cysteine modification to alter the functions of immune-relevant proteins; however, our understanding of electrophile-sensitive cysteines in the human immune proteome remains limited. Here, we present a global map of cysteines in primary human T cells that are susceptible to covalent modification by electrophilic small molecules. More than 3,000 covalently liganded cysteines were found on functionally and structurally diverse proteins, including many that play fundamental roles in immunology. We further show that electrophilic compounds can impair T cell activation by distinct mechanisms involving the direct functional perturbation and/or degradation of proteins. Our findings reveal a rich content of ligandable cysteines in human T cells and point to electrophilic small molecules as a fertile source for chemical probes and ultimately therapeutics that modulate immunological processes and their associated disorders.

A Chemical Proteomic Probe for the Mitochondrial Pyruvate Carrier Complex.

Target engagement assays are crucial for establishing the mechanism-of-action of small molecules in living systems. Integral membrane transporters can present a challenging protein class for assessing cellular engagement by small molecules. The chemical proteomic discovery of alpha-chloroacetamide (αCA) compounds that covalently modify cysteine-54 (C54) of the MPC2 subunit of the mitochondrial pyruvate carrier (MPC) is presented. This finding is used to create an alkyne-modified αCA, YY4-yne, that serves as a cellular engagement probe for MPC2 in click chemistry-enabled western blotting or global mass spectrometry-based proteomic experiments. Studies with YY4-yne revealed that UK-5099, an alpha-cyanocinnamate inhibitor of the MPC complex, engages MPC2 with remarkable selectivity in human cells. These findings support a model where UK-5099 inhibits the MPC complex by binding to C54 of MPC2 in a covalent reversible manner that can be quantified in cells using the YY4-yne probe.

[Retrosternal Giant Aortic Aneurysm;Report of Two Cases].

This is a 2-case report of successful aortic repair surgery for the retrosternal giant aortic aneurysm. Our surgical strategy is "deep hypothermia and left ventricular( LV) unloading under cardiopulmonary bypass before approaching to the aortic aneurysm" in case of possible catastrophic bleeding. Case 1, a 64-year-old woman, had a retrosternal pseudoaneurysm (80 mm) at the distal anastomosis of a Dacron graft used to replace the ascending aorta 7 years before. An LV vent tube was cannulated via the right upper pulmonary vein through an inferior T-shaped ministernotomy. Case 2, an 86-year-old woman, had a retrosternal chronic aortic dissecting aneurysm (66 mm). An LV vent cannula was inserted via the LV apex through a left minithoracotomy. Arch replacement and ascending aorta replacement were performed in Case 1 and 2, respectively, without cardiac, neurological, or any other complications. This strategy is safe and useful in a case with complex aortic disease.

Anti-PcrV titers in non-cystic fibrosis patients with Pseudomonas aeruginosa respiratory tract infection.

OBJECTIVE: The epidemiology and role of the anti-PcrV titer in non-cystic fibrosis patients with Pseudomonas aeruginosa airway tract infections is not fully understood. This study was performed to compare the anti-PcrV titers of patients with and without P. aeruginosa respiratory tract infections. METHODS: This prospective cohort study was conducted at Hokkaido University Hospital in Japan. Participants had blood and sputum specimens collected on admission. They were divided into two groups based on their sputum culture results. Those with a P. aeruginosa infection were assigned to the P. aeruginosa (PA) group and those without a P. aeruginosa infection were assigned to the non-PA group. Serum anti-PcrV titers were measured using a validated ELISA. RESULTS: Of the 44 participants, 15 were assigned to the PA group and 29 were assigned to the non-PA group. In the PA group, 10/15 participants (66.7%) had an anti-PcrV titer >1000ng/ml compared to 3/29 participants (10.3%) in the non-PA group (p<0.001). In the PA group, two of the five participants with an anti-PcrV titer <1000 ng/ml died of recurrent P. aeruginosa pneumonia; the other three participants did not develop pneumonia. CONCLUSION: The anti-PcrV titers in participants with P. aeruginosa infection varied considerably. Patients with low anti-PcrV titers and refractory P. aeruginosa infections need to be monitored closely.