ABSTRACT
The bloomy rind sign, characterized by band-like abnormalities along the surface of the brainstem on magnetic resonance imaging without contrast enhancement, has been considered a specific imaging marker for leptomeningeal metastasis from lung adenocarcinoma. In this study, we describe the case of an 85-year-old male with a 3-week history of headache, fever, and progressive cognitive impairment. The patient was diagnosed with varicella-zoster virus brainstem meningoencephalitis and magnetic resonance imaging revealed hyperintensities along the brainstem surface on fluid-attenuated inversion recovery and diffusion-weighted imaging that mimicked a bloomy rind sign. However, the patient showed no signs of lung cancer or meningeal carcinomatosis. This case suggests that the bloomy rind sign is not exclusive to leptomeningeal metastasis but can also be observed in other conditions, such as central nervous system infections.
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A 72-year-old man with diffuse large B-cell lymphoma underwent fluorine-18 fluorodeoxyglucose (FDG) PET/CT, revealing lymphoma lesions and no evidence of aortitis. The patient received chemotherapy and was treated with granulocyte colony-stimulating factor (G-CSF) for neutropenia. During chemotherapy, the patient underwent PET/CT again, revealing FDG accumulation and wall thickening at the aortic arch, which suggested aortitis. The patient was only experiencing fatigue. G-CSF-associated aortitis was suspected, and the original G-CSF was switched to another G-CSF while continuing chemotherapy. Three months later, the third round of PET/CT showed that FDG accumulation and wall thickening of the aortic arch vanished. PET/CT may be useful for not only the diagnosis but follow-up of G-CSF-associated aortitis. Radiologists should recognize incidental aortitis on PET/CT in patients receiving G-CSF administration.
ABSTRACT
In mammals, CLOCK and BMAL1 proteins form a heterodimer that binds to E-box sequences and activates transcription of target genes, including Period (Per). Translated PER proteins then bind to the CLOCK-BMAL1 complex to inhibit its transcriptional activity. However, the molecular mechanism and the impact of this PER-dependent inhibition on the circadian clock oscillation remain elusive. We previously identified Ser38 and Ser42 in a DNA-binding domain of CLOCK as phosphorylation sites at the PER-dependent inhibition phase. In this study, knockout rescue experiments showed that nonphosphorylatable (Ala) mutations at these sites shortened circadian period, whereas their constitutive-phospho-mimetic (Asp) mutations completely abolished the circadian rhythms. Similarly, we found that nonphosphorylatable (Ala) and constitutive-phospho-mimetic (Glu) mutations at Ser78 in a DNA-binding domain of BMAL1 also shortened the circadian period and abolished the rhythms, respectively. The mathematical modeling predicted that these constitutive-phospho-mimetic mutations weaken the DNA binding of the CLOCK-BMAL1 complex and that the nonphosphorylatable mutations inhibit the PER-dependent displacement (reduction of DNA-binding ability) of the CLOCK-BMAL1 complex from DNA. Biochemical experiments supported the importance of these phosphorylation sites for displacement of the complex in the PER2-dependent inhibition. Our results provide direct evidence that phosphorylation of CLOCK-Ser38/Ser42 and BMAL1-Ser78 plays a crucial role in the PER-dependent inhibition and the determination of the circadian period.
Subject(s)
ARNTL Transcription Factors , CLOCK Proteins , Circadian Clocks , Period Circadian Proteins , Animals , Humans , Mice , ARNTL Transcription Factors/metabolism , ARNTL Transcription Factors/genetics , ARNTL Transcription Factors/chemistry , Circadian Clocks/genetics , Circadian Rhythm/physiology , Circadian Rhythm/genetics , CLOCK Proteins/metabolism , CLOCK Proteins/genetics , DNA/metabolism , HEK293 Cells , Mutation , NIH 3T3 Cells , Period Circadian Proteins/metabolism , Period Circadian Proteins/genetics , Phosphorylation , Protein Binding , Protein DomainsABSTRACT
Spinal cord injury (SCI) is a devastating mechanical trauma. Although locomotion of model animals that mimic contusion SCI was actively examined, locomotion after penetrating SCI caused by sharp objects was not extensively studied. Severity of walking difficulty after partial transection of the spinal cord including penetrating SCI likely depends on the regions affected. Therefore, we compared beam walking and overground walking between mice after penetrating SCI at inner spinal cord region and mice with the injury at the outer region. Mice with the both penetrating SCIs did not display changes in beam walking. When appearance and movements of hindlimbs during overground walking was rated using Basso Mouse Scale for locomotion (BMS), however, mice with inner penetrating SCI showed low score shortly after the SCI. However, the score became high at later time points, as seen in contusion SCI mice. By contrast, BMS score did not decrease shortly after the outer penetrating SCI. However, the score became low 3 weeks after the SCI. As quantitative values during overground walking, movement duration in an open field were shorter at 1â¯day after the two penetrating SCIs. However, slower moving speed and fewer number of movement at 1â¯day were specific to mice with inner and outer penetrating SCIs, respectively. Moreover, BMS score was correlated with walking distance in open field only in mice with inner penetrating SCI. Thus, inner and outer penetrating SCI cause difficulty in overground walking with different severity and progress.
ABSTRACT
Physical compartments are essential for the origin of life. While lipid vesicles are commonly regarded as precursors of cell membranes, we propose a simpler and more primitive model based on proteinoids. Proteinoids are macromolecules formed by the thermal polymerization of amino acids, mimicking primitive proteins. They self-assemble into spherical microspheres in water. Under a temperature gradient, proteinoid microspheres (PM) dissolve and flow, forming microcapsules with thin shells. The mechanism of this process has not yet been elucidated. We hypothesize that it involves the interplay between the dissolution and flow of PM. We tested our hypothesis by applying forced flow to the PM and observing capsule formation. We found that neither heat nor flow alone can produce capsules, confirming our hypothesis. We conclude that flow-induced capsule formation is a general phenomenon and a plausible model for the origin of physical compartments in early life.
Subject(s)
Amino Acids , Proteins , Proteins/metabolism , Amino Acids/metabolism , WaterABSTRACT
BACKGROUND: Emicizumab, a factor (F) VIIIa-function mimetic bispecific antibody (BsAb) to FIXa and FX, has become an indispensable treatment option for people with hemophilia A (PwHA). However, a small proportion of PwHA still experience bleeds even under emicizumab prophylaxis, as observed in the long-term outcomes of clinical studies. A more potent BsAb may be desirable for such patients. OBJECTIVES: To identify a potent BsAb to FIXa and FX, NXT007, surpassing emicizumab by in vitro and in vivo evaluation. METHODS: New pairs of light chains for emicizumab's heavy chains were screened from phage libraries, and subsequent antibody optimization was performed. For in vitro evaluation, thrombin generation assays were performed with hemophilia A plasma. In vivo hemostatic activity was evaluated in a nonhuman primate model of acquired hemophilia A. RESULTS: NXT007 exhibited an in vitro thrombin generation activity comparable to the international standard activity of FVIII (100 IU/dL), much higher than emicizumab, when triggered by tissue factor. NXT007 also demonstrated a potent in vivo hemostatic activity at approximately 30-fold lower plasma concentrations than emicizumab's historical data. In terms of dose shift between NXT007 and emicizumab, the in vitro and in vivo results were concordant. Regarding pharmacokinetics, NXT007 showed lower in vivo clearance than those shown by typical monoclonal antibodies, suggesting that the Fc engineering to enhance FcRn binding worked well. CONCLUSION: NXT007, a potent BsAb, was successfully created. Nonclinical results suggest that NXT007 would have a potential to keep a nonhemophilic range of coagulation potential in PwHA or to realize more convenient dosing regimens than emicizumab.
Subject(s)
Antibodies, Bispecific , Hemophilia A , Hemostatics , Humans , Hemostatics/pharmacology , Hemostatics/therapeutic use , Thrombin/metabolism , Hemostasis , Blood Coagulation , Factor VIIIABSTRACT
Introduction: Combination therapy of atezolizumab and chemotherapy has become the standard treatment for small-cell lung cancer. Immune-related adverse events (irAEs) can occur during immune checkpoint inhibitor administration. A few reports exist on pure red cell aplasia (PRCA) as an irAE after atezolizumab treatment. PRCA is characterized by normocytic-normochromic anemia, a marked decrease in reticulocytes, and a decrease in bone marrow erythroblasts. Here, we report a case of atezolizumab-induced PRCA. Case Presentation: A 69-year-old male patient was brought to the emergency department with the chief complaint of seizures. Multiple metastatic brain tumors and a mass suspected to be the primary lesion in the right hilar region were observed. After a brain biopsy, he was diagnosed with small-cell lung cancer (cT1cN0M1c stage IVB). He received four courses of carboplatin, etoposide, and atezolizumab in combination with whole-brain irradiation, which led to a partial response. After six courses of atezolizumab maintenance therapy, severe anemia (hemoglobin, 3.4 g/dL) was observed. PRCA induced by atezolizumab was diagnosed using a bone marrow biopsy performed during red blood cell transfusion. Treatment was started with prednisolone 25 mg/day (0.5 mg/kg/day). Anemia improved, and the dose was gradually reduced to 5 mg/day. Conclusion: Reports of PRCA as an irAE are rare but important; hence, we reported this case.
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In human celiac disease (CeD) HLA-DQ2.5 presents gluten peptides to antigen-specific CD4+ T cells, thereby instigating immune activation and enteropathy. Targeting HLA-DQ2.5 with neutralizing antibody for treating CeD may be plausible, yet using pan-HLA-DQ antibody risks affecting systemic immunity, while targeting selected gluten peptide:HLA-DQ2.5 complex (pHLA-DQ2.5) may be insufficient. Here we generate a TCR-like, neutralizing antibody (DONQ52) that broadly recognizes more than twenty-five distinct gluten pHLA-DQ2.5 through rabbit immunization with multi-epitope gluten pHLA-DQ2.5 and multidimensional optimization. Structural analyses show that the proline-rich and glutamine-rich motif of gluten epitopes critical for pathogenesis is flexibly recognized by multiple tyrosine residues present in the antibody paratope, implicating the mechanisms for the broad reactivity. In HLA-DQ2.5 transgenic mice, DONQ52 demonstrates favorable pharmacokinetics with high subcutaneous bioavailability, and blocks immunity to gluten while not affecting systemic immunity. Our results thus provide a rationale for clinical testing of DONQ52 in CeD.
Subject(s)
Celiac Disease , Glutens , Mice , Animals , Humans , Rabbits , Glutens/chemistry , Antibodies, Neutralizing , HLA-DQ Antigens , Peptides/chemistry , Epitopes/chemistry , Mice, TransgenicABSTRACT
The aim of this study was to compare in-hospital mortality of three procedures -halo-vest immobilization, anterior spinal fixation (ASF), and posterior spinal fixation (PSF)- in the treatment of elderly patients with isolated C2 odontoid fracture. We extracted data for elderly patients who were admitted with C2 odontoid fracture and treated with at least one of the three procedures (halo-vest immobilization, ASF, or PSF) during hospitalization. We conducted a generalized propensity score-based matching weight analysis to compare in-hospital mortality among the three procedures. We further investigated independent risk factors for in-hospital death. The study involved 891 patients (halo-vest, n = 463; ASF, n = 74; and PSF, n = 354) with a mean age of 78 years. In-hospital death occurred in 45 (5.1%) patients. Treatment type was not significantly associated with in-hospital mortality. Male sex (odds ratio 2.98; 95% confidence interval 1.32-6.73; p = 0.009) and a Charlson comorbidity index of ≥ 3 (odds ratio 9.18; 95% confidence interval 3.25-25.92; p < 0.001) were independent risk factors for in-hospital mortality. In conclusion, treatment type was not significantly associated with in-hospital mortality in elderly patients with isolated C2 odontoid fracture. Halo-vest immobilization can help to avoid adverse events in patients with C2 odontoid fracture who are considered less suitable for surgical treatment.
Subject(s)
Fractures, Bone , Odontoid Process , Spinal Fractures , Spinal Fusion , Humans , Male , Aged , Hospital Mortality , Odontoid Process/surgery , Spinal Fractures/surgery , Risk Factors , Treatment OutcomeABSTRACT
PURPOSE: The possibility of steroid administration inducing the extensive skeletal muscle uptake (ESMU) of FDG in PET scans was investigated. METHODS: From 8923 consecutive 18 F-FDG PET/CT scans taken at our hospital, 23 scans (15 patients) met adult age and ESMU-positive inclusion criteria. Among the 15 patients, 13 with both ESMU-positive and -negative scans were examined for association with steroid administration. RESULTS: Extensive skeletal muscle uptake was associated with a history of steroid administration ( χ2 test: P = 0.001). Notably, 20 ESMU-positive scans and 11 ESMU-negative scans were significantly different, with 0 to 95 days (median, 18.5 days) and 0 to 708 days (median, 319.0 days) since the last steroid administration, respectively (Mann-Whitney U test, P = 0.003). A significant correlation was observed between mean skeletal muscle SUV max and the number of days since the last steroid administration (Spearman rank correlation coefficient, ρ = -0.501, P = 0.004). Specifically, the degree of ESMU tended to decrease over time, after steroid administration. From multiple regression analysis, the number of days since the last steroid administration was significantly associated with mean SUV max ( P = 0.007), but the blood glucose level was not significant ( P = 0.204), revealing that the number of days since the last steroid administration was an independent risk factor. Multicollinearity was low (the variance inflation factor was 1.007 for both the number of days since the last steroid administration and blood glucose levels). CONCLUSIONS: Steroid administration within months before PET may be one cause of ESMU.
Subject(s)
Fluorodeoxyglucose F18 , Positron Emission Tomography Computed Tomography , Adult , Humans , Radiopharmaceuticals , Blood Glucose , Positron-Emission Tomography , Muscle, Skeletal , SteroidsABSTRACT
Therapeutic antibodies sometimes elicit anti-drug antibodies (ADAs) that can affect efficacy and safety. Engineered antibodies that contain artificial amino acid sequences are potentially highly immunogenic, but this is currently difficult to predict. Therefore, it is important to efficiently assess immunogenicity during the development of complex antibody-based formats. Here, we present an in vitro peripheral blood mononuclear cell-based assay that can be used to assess immunogenicity potential within 3 days. This method involves examining the frequency and function of interleukin (IL)-2-secreting CD4+ T cells induced by therapeutic antibodies. IL-2-secreting CD4+ T cells seem to be functionally relevant to the immunogenic potential due to their proliferative activity and the expression of several cytokines. The rates of the donors responding to low and high immunogenic proteins, mAb1, and keyhole limpet hemocyanin were 1.3% and 93.5%, respectively. Seven antibodies with known rates of immunogenicity (etanercept, emicizumab, abciximab, romosozumab, blosozumab, humanized anti-human A33 antibody, and bococizumab) induced responses in 1.9%, 3.8%, 6.4%, 10.0%, 29.2%, 43.8%, and 89.5% of donors, respectively. These data are comparable with ADA incidences in clinical settings. Our results show that this assay can contribute to the swift assessment and mechanistic understanding of the immunogenicity of therapeutic antibodies.
Subject(s)
Interleukin-2 , T-Lymphocytes , Interleukin-2/pharmacology , Leukocytes, Mononuclear/metabolism , Cytokines/metabolism , CD4-Positive T-LymphocytesABSTRACT
STUDY DESIGN: A retrospective study. OBJECTIVE: The aim of this study was to clarify preoperative radiographic predictors associated with the development of subaxial subluxation (SAS) after surgery. BACKGROUND: The incidence of atlantoaxial fusion for atlantoaxial instability has been increasing. SAS can develop after surgery despite atlantoaxial fusion with the optimal C1-C2 angle. We hypothesized that preoperative discordant angular contribution in the upper and subaxial cervical spine is associated with the occurrence of postoperative SAS. MATERIALS AND METHODS: Patients who underwent surgery for atlantoaxial instability with a minimum 5-year follow-up and control participants were included. The O-C2 angle, C2 slope (C2S), C2-C7 cervical lordosis (CL), and T1 slope (T1S) were measured. We focused on the angular contribution ratio in the upper cervical spine to the whole CL, and the preoperative C2/T1S ratio was defined as the ratio of C2S to T1S. RESULTS: Twenty-seven patients (SAS=11, no-SAS=16; mean age, 60.7 y old; 77.8% female; mean follow-up duration, 6.8 y) and 23 demographically matched control participants were enrolled. The SAS onset was at 4.7 postoperative years. Preoperatively, the O-C2 angle, C2-C7 CL, and T1S were comparable between the SAS, no-SAS, and control groups. The preoperative C2S and C2/T1S ratio were smaller in the SAS group than in the no-SAS or control group (C2S, 11.0 vs. 18.4 vs. 18.7 degrees; C2/T1S ratio, 0.49 vs. 0.77 vs. 0.78, P <0.05). The receiver operating characteristic curve analysis demonstrated that the C2/T1S ratio had higher specificity and similar sensitivity as a predictor of postoperative SAS than C2S (specificity: 0.90 vs. 0.87; sensitivity: 0.73 vs. 0.73). The estimated cutoff values of the C2S and C2/T1S ratio were 14 degrees and 0.58, respectively. CONCLUSIONS: The preoperative C2/T1S ratio was closely associated with postoperative SAS. Patients with a C2/T1S ratio <0.58 were at a high risk of SAS after atlantoaxial fusion. LEVEL OF EVIDENCE: Level 4.
Subject(s)
Joint Dislocations , Joint Instability , Lordosis , Spinal Fusion , Humans , Female , Middle Aged , Male , Retrospective Studies , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/surgery , Lordosis/surgery , Joint Dislocations/diagnostic imaging , Joint Dislocations/surgery , Joint Dislocations/complications , Joint Instability/diagnostic imaging , Joint Instability/etiology , Joint Instability/surgery , Spinal Fusion/adverse effectsABSTRACT
STUDY DESIGN: Retrospective cohort study. OBJECTIVES: This study aimed to investigate whether early surgery shortens the duration of opioid use in patients who underwent surgery with lumbar disc herniation. METHODS: We extracted patients who underwent surgery at least 2 weeks after they were diagnosed with lumbar disc herniation between April 2014 and May 2021. Opioid use after surgery was compared between patients who underwent surgery within 90 days (early surgery group) and 90 days or later (late surgery group). Propensity-score-matching analysis and multivariable Cox hazard regression analysis with a restricted cubic spline model were conducted to evaluate the association between the timing of surgery and termination of opioid use after surgery. RESULTS: A total of 1597 eligible patients were identified, with 807 (51%) in the early surgery group. In the propensity-score-matched cohort, the early surgery group had a significantly lower proportion of opioid use than the control group (28% vs 48%, percent difference -20%, P < .001). Multivariable Cox hazard regression analysis showed that early surgery was significantly associated with the earlier termination of opioid use (HR, 3.13; 95% CI, 1.97-4.97; P < .001). Restricted cubic spline model showed a monotonically decreased hazard ratio and decreased hazard ratio of .50 in patients who underwent surgery 111 days or later after the diagnosis. CONCLUSIONS: Early surgery, especially within 90 days, was associated with earlier opioid use termination after surgery. Regarding the duration of opioid use following surgery, surgical treatment may be preferable to perform within around 4 months after the diagnosis.
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PURPOSE: This study aimed to determine the association of preoperative malnutrition with an increased risk of cervical kyphosis after laminoplasty in geriatric patients with cervical spondylotic myelopathy (CSM). METHODS: Geriatric patients who underwent cervical laminoplasty were included. Malnutrition was defined as a geriatric nutritional risk index < 98 before surgery. The C2-7 angle and the global alignment parameters were analyzed on standing radiographs. The postoperative kyphosis was defined as a C2-7 angle < 0° during a 2-year follow-up. RESULTS: Ninety patients without preoperative kyphotic alignment were enrolled (mean age, 73.5 years old; 41.1% female). Twenty-one patients (23.3%) had malnutrition status (74.2 years old). Preoperatively, the global alignment parameters were comparable between the malnutrition and normal nutrition groups (SVA, 43.3 mm vs. 42.4 mm; T1S, 29.7° vs. 28.4°; TPA, 21.4° vs. 17.8°), with no significant difference in the C2-7 angle (15.1° vs. 15.2°). At 2 years postoperatively, the malnutrition group showed a significantly lower C2-7 angle than the normal nutrition group (9.3° vs. 15.8°, P = 0.03). Postoperative kyphosis was more prevalent in the malnutrition group (33.3% vs. 7.2%, P = 0.005). The preoperative nutritional status and C2-7 angle were independent predictors of postoperative kyphosis. The predictive C2-7 angles differed by preoperative nutritional status (malnutrition group, 11°; normal nutrition group, 7°). CONCLUSION: Among geriatric CSM patients, preoperative malnutrition was closely associated with the increased occurrence of cervical kyphosis after laminoplasty. Our results underscore the importance of preoperative nutritional assessment and management in geriatric populations undergoing cervical spine surgery, as malnutrition is a perioperative modifiable risk factor.
Subject(s)
Kyphosis , Laminoplasty , Malnutrition , Spinal Cord Diseases , Humans , Female , Aged , Male , Laminoplasty/adverse effects , Laminoplasty/methods , Nutritional Status , Kyphosis/diagnostic imaging , Kyphosis/epidemiology , Kyphosis/surgery , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/surgery , Spinal Cord Diseases/surgery , Malnutrition/complications , Malnutrition/epidemiology , Retrospective StudiesABSTRACT
STUDY DESIGN: Retrospective cohort study. OBJECTIVES: This study aimed to examine whether the use of intravenous TXA in elective spine surgery is associated with reduced perioperative massive hemorrhage requiring transfusion. METHODS: We extracted all patients who underwent decompression with or without fusion surgery for the cervical, thoracic, and lumbar spine between April 2012 and March 2019. The primary outcome was the occurrence of massive hemorrhage requiring transfusion, defined as at least 560 mL of blood transfusion within 2 days of spine surgery or the requirement of additional blood transfusion from 3-7 days postoperatively. Secondary outcomes were the occurrence of thrombotic complications (pulmonary embolism, acute coronary syndrome, and stroke) and postoperative hematoma requiring additional surgery. RESULTS: We identified 83,821 eligible patients, with 9747 (12%) patients in the TXA group. Overall, massive hemorrhage requiring transfusion occurred in 781 (.9%) patients. Propensity score matching yielded 8394 pairs. In the matched cohort, the TXA group had a lower proportion of massive hemorrhage requiring transfusion than the control group (.7% vs 1.1%; P = .002). There was no significant difference in the occurrence of thrombotic complications and postoperative hematoma requiring additional surgery between both groups. The multivariable regression analysis also showed that the use of TXA was associated with significantly lower proportions of massive hemorrhage requiring transfusion (odds ratio, .62; 95% confidence interval, .43-.90; P = .012). CONCLUSIONS: In this analysis using real-world data, TXA use in elective spinal surgery was associated with reduced perioperative massive hemorrhage requiring transfusion without increasing thrombotic complications. LEVEL OF EVIDENCE: Prognostic Level â ¢.
ABSTRACT
Precise evaluation of motor functions using simple and reproducible tests for mouse models of spinal cord injury (SCI) are required. Overground walking of SCI mice has been tested by Basso Mouse Scale for locomotion (BMS). In contrast, only a few works quantify walking performances of SCI mice on narrow beams, a different task. Here, we established a novel scoring system using a single beam walking apparatus for SCI mice. The scoring system uses binary judgments of values such as retention, moving forward and reaching the goal on a beam for rating. In addition, high score was given to SCI mouse when the mouse efficiently used hindlimbs for locomotion on the beam. A high rate of concordance of the score derived from positions of hindlimbs between two observers was obtained. Mice displayed the lowest total score on the beam immediately after the SCI, then the score gradually increased like time course of BMS score. Furthermore, the total scores reflected gradation of severity of SCI in 2 strains of mice. The beam walking score proved to be strongly correlated with that of BMS score, indicating that performances between overground walking and beam walking are partly correlated in SCI mice. Collectively, the novel scoring system offers an opportunity to easily evaluate motor performances of mice with SCI.
Subject(s)
Spinal Cord Injuries , Animals , Locomotion , Mice , Mice, Inbred C57BL , Recovery of Function , Spinal Cord , WalkingABSTRACT
Aims: The circadian clock oscillates in a cell-autonomous manner with a period of â¼24 h, and the phase is regulated by various time cues such as light and temperature through multiple clock input pathways. We previously found that osmotic and oxidative stress strongly affected the circadian period and phase of cellular rhythms, and triple knockout of apoptosis signal-regulating kinase (ASK) family members, Ask1, Ask2, and Ask3, abolished the phase shift (clock resetting) induced by hyperosmotic pulse treatment. We aimed at exploring a key molecule(s) and signaling events in the clock input pathway dependent on ASK kinases. Results: The phase shift of the cellular clock induced by the hyperosmotic pulse treatment was significantly reduced by combined deficiencies of the clock(-related) genes, Dec1, Dec2, and E4 promoter-binding protein 4 (also known as Nfil3) (E4bp4). In addition, liquid chromatography mass/mass spectrometry (LC-MS/MS)-based proteomic analysis identified hyperosmotic pulse-induced phosphorylation of circadian locomotor output cycles caput (CLOCK) Ser845 in an AKT-dependent manner. We found that AKT kinase was phosphorylated at Ser473 (i.e., activated) in response to the hyperosmotic pulse experiments. Inhibition of mechanistic target of rapamycin (mTOR) kinase by Torin 1 treatment completely abolished the AKT activation, suppressed the phosphorylation of CLOCK Ser845, and blocked the clock resetting induced by the hyperosmotic pulse treatment. Innovation and Conclusions: We conclude that mTOR-AKT signaling is indispensable for the CLOCK Ser845 phosphorylation, which correlates with the clock resetting induced by the hyperosmotic pulse treatment. Immediate early induction of the clock(-related) genes and CLOCK carboxyl-terminal (C-terminal) region containing Ser845 also play important roles in the clock input pathway through redox-sensitive ASK kinases. Antioxid. Redox Signal. 37, 631-646.
Subject(s)
Circadian Rhythm , Proto-Oncogene Proteins c-akt , Chromatography, Liquid , Circadian Rhythm/genetics , Osmotic Pressure , Proteomics , Sirolimus , TOR Serine-Threonine Kinases , Tandem Mass Spectrometry , Transcription Factors/metabolismABSTRACT
STUDY DESIGN: Retrospective cohort study. OBJECTIVES: We aimed to clarify the clinical relationship between the etiology of proximal-type cervical spondylotic amyotrophy (CSA) and cervical sagittal alignment and instability. SUMMARY OF BACKGROUND DATA: Although several researchers have discussed hypotheses regarding the etiology of CSA, the trigger and mechanism underlying the onset remain unclear. METHODS: We retrospectively analyzed 52 proximal-type CSA patients (CSA group) and 60 control patients (Control group). The following data were collected: age; sex; cervical lordosis (CL); T1 slope (TS); TS-CL; C2-7 sagittal vertical axis (SVA) on x-ray in the neutral position; flexion angle; extension angle and range of motion (ROM) of C3/4, C4/5 and C5/6; and C3/4, C4/5 and C5/6 instability (translation of >3 mm for adjacent segmental segments) on dynamic x-ray. RESULTS: Compared with the Control group, the CSA group was associated with an older age (mean age, 67.6 vs. 61.1 years' old, P= 0.029) and male sex (78.8% vs. 50.0%, P= 0.002). In the CSA group, the radiographic parameters showed smaller C4/5 and C5/6 extension angles and C5/6 ROM values and a greater C3/4 flexion angle than the Control group. Furthermore, compared with the Control group, the CSA group was associated with C3/4 instability (13.5% vs. 3.3%, P= 0.049) and C4/5 (21.2% vs. 3.3%, P = 0.003). A logistic regression analysis, with adjusting for the age and sex, showed that the C3/4 flexion angle (odds ratio [OR], 1.2; 95% confidence interval [CI], 1.08- 1.40, P =0.002), C3/4 instability (OR, 7.3; 95% CI 1.25-42.96, P =0.027) and C4/5 instability (OR, 8.1; 95% CI, 1.56-42.19, P = 0.012) were independent risk factors of CSA. CONCLUSION: This study suggested that a wide C3/4 flexion angle and high C3/4 or C4/5 spinal instability were closely associated with the etiology of proximal-type CSA.