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Akio Sakamoto, Shuzo Okudaira, Yuta Onishi, Takashi Noguchi, Shuichi Matsuda The Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Kyoto, JapanCorrespondence: Akio Sakamoto, The Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Shogoin, Kawahara-cho 54, Sakyo-ku, Kyoto, 606-8507, Japan, Tel +8175-751-3366, Fax +81-75-751-8409, Email akiosaka@kuhp.kyoto-u.ac.jpAbstract: Stress fractures of the first rib are uncommon and thought to be associated with overhead-throwing athletes. Soft tennis is similar to regular tennis but uses a much softer rubber ball. In the current report, a 14-year-old girl suffered from shoulder girdle pain, especially at the end of her tennis ground stroke. Plain radiographs showed overgrowth of bone with a fracture line on the first rib, and a diagnosis of stress fracture was made. She was advised to amend her stroke form to reduce force to the shoulder and was able to continue sports activity without pain 10 months after the appearance of her symptoms and before confirmation of bone healing. The current case is not associated with overhead-throwing, but possibly with repetitive exercises of her tennis ground strokes. Conservative medical follow-up with proper sport-specific professional advice allows continuation of the sport.Plain Language Summary: Stress fractures of the first rib are rare, mainly linked to overhead-throwing athletes. Soft tennis resembles regular tennis but uses a softer rubber ball. In this case, a 14-year-old girl with shoulder girdle pain, especially during tennis strokes, was diagnosed with a first rib stress fracture via plain radiographs. She improved by adjusting her stroke and resumed sports pain-free within 10 months, even before full bone healing. This case was not linked to overhead-throwing but potentially resulted from repetitive ground strokes. Proper medical guidance supports sport continuation.Keywords: first rib, stress fracture, tennis, tennis stroke

Soichiro Matsuda,1 Yuki Igawa,1,2 Hidekazu Uchisawa,1,2 Shinya Iki,3 Michihiro Osumi1,4 1Graduate School of Health Sciences, Kio University, Nara, Japan; 2Department of Rehabilitation, Nishiyamato Rehabilitation Hospital, Nara, Japan; 3Department of Rehabilitation, Kawaguchi Neurosurgery Rehabilitation Clinic, Osaka, Japan; 4Neurorehabilitation Research Center, Kio University, Nara, JapanCorrespondence: Soichiro Matsuda, Graduate School of Health Sciences, Kio University, 4-2-2 Umaminaka, Kitakatsuragigun, Nara, 635-0832, Japan, Tel +745-54-1601, Fax +745-54-1600, Email f1996957@kio.ac.jpPurpose: In the thermal grill illusion, participants experience a feeling similar to burning pain. The illusion is induced by simultaneously touching warm and cool stimuli in alternating positions. In post-stroke pain, central sensitization is caused by a variety of factors, including damage to the spinothalamic tract and shoulder pain. Because the thermal grill illusion depends on central mechanisms, it has recently been suggested that it may be a useful indicator of central sensitization. Therefore, we hypothesized that post-stroke patients who are more likely to experience central sensitization may also be more likely to experience a thermal grill sensation of pain and discomfort than the likelihood among those who are less likely to experience central sensitization. However, the effects of the thermal grill illusion in post-stroke patients have not yet been reported. In this pilot study, we conducted the thermal grill illusion procedure in post-stroke patients and analyzed the relationship between clinical somatosensory functions and thermal grill sensations. We also conducted brain imaging analysis to identify brain lesion areas that were associated with thermal grill sensations.Patients and Methods: Twenty patients (65.7 ± 11.9 years old) with post-stroke patients participated in this study. The thermal grill illusion procedure was performed as follows: patients simultaneously touched eight water-filled copper bars, with the water temperature adjusted to provide alternate warm (40°C) and cold (20°C) stimuli.Results: Thermal grill sensation of pain and discomfort tended to be associated with the wind-up phenomenon in bedside quantitative sensory testing and thermal grill sensation of discomfort was also related to damage to the thalamic lateral nucleus.Conclusion: These findings suggest that the thermal grill illusion might measure central sensitization, and that secondary brain hyperactivity might lead to increased thermal grill sensations.Keywords: thermal grill illusion, post stroke pain, central sensitization, thalamus, insula

Pulsating Aurora (PsA) is one of the major classes of diffuse aurora associated with precipitation of a few to a few tens of keV electrons from the magnetosphere. Recent studies suggested that, during PsA, more energetic (i.e., sub‐relativistic/relativistic) electrons precipitate into the ionosphere at the same time. Those electrons are considered to be scattered at the higher latitude part of the magnetosphere by whistler‐mode chorus waves propagating away from the magnetic equator. However, there have been no actual cases of simultaneous observations of precipitating electrons causing PsA (PsA electrons) and chorus waves propagating toward higher latitudes; thus, we still do not quite well understand under what conditions PsA electrons become harder and precipitate to lower altitudes. To address this question, we have investigated an extended interval of PsA on 12 January 2021, during which simultaneous observations with the Arase satellite, ground‐based all‐sky imagers and the European Incoherent SCATter (EISCAT) radar were conducted. We found that, when the PsA shape became patchy, the PsA electron energy increased and Arase detected intense chorus waves at magnetic latitudes above 20°, indicating the propagation of chorus waves up to higher latitudes along the field line. A direct comparison between the irregularities of the magnetospheric electron density and the emission intensity of PsA patches at the footprint of the satellite suggests that the PsA morphology and the energy of PsA electrons are determined by the presence of "magnetospheric density ducts," which allow chorus waves to travel to higher latitudes and thereby precipitate more energetic electrons. Plain Language Summary: Pulsating Aurora (PsA) is a kind of diffuse aurora associated with periodic precipitation of energetic electrons from the near‐Earth space into the atmosphere. Recent research has shown that, during PsA events, energetic particles at the sub‐relativistic energy range precipitate into the atmosphere. We speculate that such particles are scattered by wave‐particle resonance with natural electromagnetic waves, called chorus waves, at higher magnetic latitude regions. However, there has been no experimental case of PsA during which propagation of the chorus waves to higher magnetic latitudes was confirmed; thus, we still do not fully understand when and why PsA electrons become more energetic. Here, we investigate a PsA event on 12 January 2021, simultaneously observed by the Arase satellite, ground‐based all‐sky imagers and the European Incoherent SCATter (EISCAT) radar. We found that, when the PsA shape was patchy, the energy of precipitating electrons increased and chorus waves were observed at high latitudes in the magnetosphere. Comparing the magnetospheric electron density with the PsA brightness seen from the ground, we suggest that both the PsA shape and the energy of precipitating electrons were influenced by the so‐called magnetospheric ducts, which guide chorus waves to high‐latitudes regions where they interact with more energetic electrons. Key Points: Examined simultaneous observations of Pulsating Aurora (PsA) with the Arase satellite, ground‐based all‐sky imagers, and the EISCAT radarFound a relationship among the patchy PsA, the enhanced energy of PsA electrons, and the chorus wave propagation to high‐latitudes (>20°)Arase observations suggest that the observed relationship can be explained by the ducted propagation of chorus waves [ABSTRACT FROM AUTHOR]

Yasumasa Otori, Takanori Matsuoka, Miho Kumoi, Eri Tachibana, Chieko Tsujino, Satoshi Matsuda Department of Ophthalmology, National Hospital Organization, Osaka National Hospital, Osaka, JapanCorrespondence: Yasumasa Otori Email otori.yasumasa.fe@mail.hosp.go.jpPurpose: To compare the outcomes of ab interno suture trabeculotomy (AbI-TLO) and ab externo metal trabeculotomy (AbE-TLO) in adult patients with glaucoma aged over 40 years.Patients and Methods: A retrospective chart review was conducted, including adult patients with glaucoma who underwent AbI-TLO or AbE-TLO between January 2015 and June 2019. A single surgeon (YO) performed all the operations. Eighty-one patients (81 eyes) were included in this study. Surgical success was defined as a postoperative intraocular pressure (IOP) of ≤ 18 mmHg and an IOP reduction of ≥ 20% from the preoperative IOP, without requiring additional glaucoma surgery. Success rates were assessed using Kaplan–Meier survival curves and log-rank (Mantel–Cox) tests, while risk factors were analyzed using the Cox proportional hazards model.Results: Forty-nine patients who underwent AbI-TLO and 32 patients who underwent AbE-TLO were studied; the preoperative IOPs were 27.9 ± 7.3 (mean ± standard deviation) mmHg and 25.6 ± 8.1 mmHg in the AbI-TLO and AbE-TLO groups, respectively (p=0.217). The 12-month postoperative IOPs were 15.8 ± 4.0 mmHg and 16.3 ± 4.2 mmHg in the AbI-TLO and AbE-TLO groups, respectively (p=0.724). The surgical success rates at 12 months were 77.6% and 62.5% in the AbI-TLO and AbE-TLO groups, respectively (p=0.144). Postoperative hyphema with level formation and ocular hypertension over 30 mmHg were observed in 22.4% and 26.5% of patients in the AbI-TLO group and 18.8% and 12.5% of those in the AbE-TLO group, respectively. Stepwise multivariate Cox regression analysis showed that a longer axial length was a risk factor for surgical failure (hazard ratio: 2.030; p=0.042).Conclusion: AbI-TLO and AbE-TLO had similar surgical outcomes and postoperative complications. A longer axial length was associated with an insufficient IOP reduction.Keywords: axial length, gonio-assisted transluminal trabeculotomy, intraocular pressure, MIGS, outcomes, trabeculotomy

Yutaka Kuroda, Toshiyuki Kawai, Koji Goto, Shuichi Matsuda Department of Orthopaedic Surgery, Graduate School of Medicine, Kyoto University, Shogoin, Sakyo-ku, Kyoto, Japan Abstract: Corticosteroids have been widely used for the treatment of various inflammatory diseases because they provide an acute response of immunosuppression. Numerous side effects of corticosteroids have also been known, with varying degrees of severity. Osteonecrosis of the femoral head (ONFH) is a rare and serious complication that directly inhibits walking because of femoral head collapse. However, sometimes, clinicians who consider that corticosteroids are required for primary disease do not recognize steroid-induced ONFH. The final stage of ONFH is severe osteoarthritis, requiring total hip arthroplasty. We describe a 23-year-old woman with bilateral ONFH after corticosteroid treatment for alopecia areata (AA). She was administered several intralesional corticosteroid injections to the scalp and repeated systemic corticosteroid therapy for extensive AA. While undergoing therapy, she lost her balance and complained of right groin pain when standing. The patient was subsequently diagnosed with bilateral ONFH. She recovered from AA, but she complained of persistent right hip pain, which subsequently required total hip arthroplasty. We would like to emphasize that patients on corticosteroid therapy for any common disease should be considered as having a potential risk for ONFH. An early stage detection of ONFH is crucial for its treatment. MRI evaluation warrants a higher level of accuracy in early diagnosis of ONFH for the opportunity to undergo joint-preservation surgery in patients with ONFH. Keywords: osteonecrosis, femoral head, alopecia areata, avascular necrosis, steroid, case report

Patients with chronic lung disease, obesity, and other co-morbid conditions are at increased risk of severe illness and death when infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Hypercapnia, the elevation of CO2 in blood and tissue, commonly occurs in patients with severe acute and chronic lung disease, including those with pulmonary infections, and is also associated with high mortality risk. We previously reported that hypercapnia increases viral replication and mortality of influenza A virus infection in mice. We have also shown that culture in elevated CO2 upregulates expression of cholesterol synthesis genes in primary human bronchial epithelial cells. Interestingly, factors that increase the cholesterol content of lipid rafts and lipid droplets, platforms for viral entry and assembly, enhance SARS-CoV-2 infection. In the current study, we investigated the effects of hypercapnia on ACE2 expression and entry of SARS-CoV-2 pseudovirus (p-SARS-CoV-2) into airway epithelial cells. We found that hypercapnia increased ACE2 expression and p-SARS-CoV-2 uptake by airway epithelium in mice, and in cultured VERO and human bronchial epithelial cells. Hypercapnia also increased total cellular and lipid raft-associated cholesterol in epithelial cells. Moreover, reducing cholesterol synthesis with inhibitors of sterol regulatory element binding protein 2 (SREBP2) or statins, and depletion of cellular cholesterol, each blocked the hypercapnia-induced increases in ACE2 expression and p-SARSCoV-2 entry into epithelial cells. Cigarette smoke extract (CSE) also increased ACE2 expression, p-SARS-CoV-2 entry and cholesterol accumulation in epithelial cells, an effect not additive to that of hypercapnia, but also inhibited by statins. These findings reveal a mechanism that may account, in part, for poor clinical outcomes of SARS-CoV-2 infection in patients with advanced lung disease and hypercapnia, and in those who smoke cigarettes. Further, our results suggest the possibility that cholesterol-lowering therapies may be of particular benefit in patients with hypercapnia when exposed to or infected with SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Author(s): S. Kasahara (corresponding author) [1]; Y. Miyoshi [2]; S. Yokota [3]; T. Mitani [4]; Y. Kasahara [5]; S. Matsuda [2]; A. Kumamoto [6]; A. Matsuoka [4]; Y. Kazama [7]; [...]

A physical mechanism to produce pulsating aurora (PsA) has been considered to be the interaction of the electron and the chorus wave generated near the equatorial plane of the magnetosphere. A recent observation of high temporal resolution of chorus waves by the Arase satellite revealed that the presence or absence of the internal modulation of PsA, which is a characteristic sub‐second scintillation at 3 ± 1 Hz within each optical pulsation, is closely related to the discreteness of the element structure of the chorus wave. However, it is still unclear what parameters (or conditions) control the discreteness of the element and the existence of the internal modulation of PsA. In this study, we discuss parameters that determine the presence or absence of the internal modulation of PsA and element structure of chorus by showing a conjugate observation of PsA/chorus by ground‐based cameras and the Arase satellite. During the event, the occurrence of internal modulation increased temporally. The wave data from the satellite show that the repetitive frequency of elements was ∼6 Hz when the internal modulation was indistinct, while the repetitive frequency was ∼3 Hz when the internal modulation was distinct. The particle measurements suggest that this difference was caused by changes in the density and the temperature anisotropy of the hot electron. The internal modulation was clearly observed when the density of hot electrons decreased and the temperature anisotropy relaxed after the injection. Observations of internal modulations from the ground might allow us to estimate the parameters such as energetic electron density and temperature anisotropy in the magnetosphere. Key Points: We analyzed a pulsating aurora (PsA) event in which the occurrence frequency of internal modulation increased significantly with timeA conjugate observation with Arase suggests that a sudden enhancement of energetic electrons by the injection caused non‐modulated PsAsThe internal modulation may be more often observed after the injection as the density of energetic electrons decreases in the magnetosphere [ABSTRACT FROM AUTHOR]

A new empirical density model is developed for the inner zone between 1 < L < 3 using plasma densities inferred from the upper hybrid resonance on Arase, and hiss‐inferred density values from Van Allen Probes. The Van Allen Probes hiss‐inferred densities are first recalibrated and validated against Arase observations, using both a conjunction event and statistical analyses. The newly developed density model includes dependencies on L, magnetic latitude, and magnetic local time (MLT). Between 1.5 < L < 3.0, the equatorial density variation with L is shown to be equivalent to that of the Ozhogin et al. (2012, https://doi.org/10.1029/2011JA017330) model. However, for L < 1.5, this dependence changes as the plasma density increases at a faster rate with decreasing L. The latitudinal dependence of the plasma density is shown to present a flatter profile than previous models, meaning lower densities extend to higher latitudes. This dependence is well‐modeled by updated fitting coefficients. A clear MLT dependence of the plasma density is identified, which was not found or included in some previous models. This variation is consistent with the diurnal variation of the ionosphere, peaking near MLT = 14 and becoming larger in amplitude with decreasing L. A function describing this MLT dependence is presented. Overall, the new L, latitude, and MLT‐dependent empirical model can provide density values in areas outside the validity region of many previous models, making it a useful resource for accurately determining diffusion coefficients and predicting electron dynamics and their lifetimes in the inner radiation belt. Key Points: Radiation Belt Storm Probes and Arase data are used to build a new empirical plasma density model for the inner zone, including L, latitude, and magnetic local time (MLT) dependenciesMLT dependence consistent with diurnal variation of ionosphere. Variation is largest in amplitude at low L, but persists out to L = 3New model provides density in areas outside previous model bounds, making it a useful resource for modeling inner radiation belt dynamics [ABSTRACT FROM AUTHOR]

Currently, biological disease-modifying anti-rheumatic drugs (bDMARDs) with different modes of action [tumour necrosis factor inhibitor (TNFi), interleukin-6 receptor inhibitor (IL-6Ri), or cytotoxic T-lymphocyte antigen 4–immunoglobulin (CTLA4-Ig)] are used in clinical practice to treat rheumatoid arthritis (RA). However, it is unclear which type of bDMARD is the most efficacious for a specific clinical situation. C-reactive protein (CRP) is an acute-phase reactant driven by IL-6 signalling. Here, we aimed to establish whether therapeutic efficacy differs between IL-6Ri and other bDMARDs with alternative modes of action in RA patients according to their CRP level. RA patients treated with bDMARDs were enrolled from an observational multicentre registry in Japan. Patients were classified into three groups according to baseline CRP tertiles. The overall 3 year retention rates of each bDMARD category were assessed. The Clinical Disease Activity Index (CDAI) was also assessed before and 3, 6, and 12 months after bDMARD initiation. A total of 1438 RA patients were included and classified into three groups according to tertiles of baseline CRP levels (CRP1, 0–0.3; CRP2, 0.3–1.8; CRP3, 1.8–18.4 mg/dL). In CRP3, the overall 3 year drug retention rates were significantly higher for IL-6Ri than for TNFi and CTLA4-Ig (77.5 vs 48.2 vs 67.3, respectively). No significant difference was evident in terms of CDAI 12 months after bDMARD initiation in CRP1–CRP3. IL-6Ri may be a favourable therapeutic option over TNFi and CTLA4-Ig in RA patients with high CRP levels. [ABSTRACT FROM AUTHOR]

We propose an accurate calibration method for short‐time waveform signals passed through a linear time‐invariant (LTI) system that has a non‐negligible group delay. Typically, the calibration process of waveform data is expressed by the deconvolution in the time domain, and there is an equivalent operation in the frequency domain with the Fourier transform. For the short‐time data, if the short‐time Fourier transform is applied to the waveform data in the calibration process, multiplying the data by a window function is highly recommended to reduce side‐lobe effects. However, the multiplied window function is also modified in the calibration process. We analyzed the modification mathematically and derived a method to eliminate the modification of the multiplied window function. In the method, calibrated data in the frequency domain are inverse‐transformed into waveform data at each frequency, divided by a modified window function at each frequency, and accumulated over the frequencies. The principle of this method derived quantitatively indicates that the calibration accuracy depends on the transfer function of the system, frequency resolution of the Fourier transform, type of the window function, and typical frequency of the waveform data. Compared with conventional calibration methods, the proposed method provides more accurate results in various cases. This method should be useful for the calibration of general radio wave signals passed through LTI systems as well as for the calibration of plasma waves observed in space. Key Points: We propose a calibration method using short‐time Fourier transform (STFT) for waveform data, such as plasma waves observed in spaceThe accuracy of the method is evaluated using the transfer functions of well‐known filters and frequency‐fixed sinusoidal waveformsThe proposed method provides the most accurately calibrated data compared with conventional methods using STFT [ABSTRACT FROM AUTHOR]

Microbursts are impulsive (<1 s) injections of electrons into the atmosphere, thought to be caused by nonlinear scattering by chorus waves. Although attempts have been made to quantify their contribution to outer belt electron loss, the uncertainty in the overall size and duration of the microburst region is typically large, so that their contribution to outer belt loss is uncertain. We combine datasets that measure chorus waves (Van Allen Probes [RBSP], Arase, ground‐based VLF stations) and microburst (>30 keV) precipitation (FIREBIRD II and AC6 CubeSats, POES) to determine the size of the microburst‐producing chorus source region beginning on 5 December 2017. We estimate that the long‐lasting (∼30 hr) microburst‐producing chorus region extends from 4 to 8 Δ ${\Delta}$MLT and 2–5 Δ ${\Delta}$L. We conclude that microbursts likely represent a major loss source of outer radiation belt electrons for this event. Plain Language Summary: Microbursts are short‐duration (<1 s) bursts of electrons that precipitate from the magnetosphere into the atmosphere. Microbursts are thought to be a result of scattering by a plasma wave called chorus. Attempts have been made to understand the contribution microburst precipitation has on electron loss, which helps the outer radiation belt recover after enhancements during storms. The contribution depends on the overall size and duration of the microburst region. We combine datasets that measure chorus waves and microburst precipitation to determine the size and duration of a microburst region beginning on 5 December 2017. Our results show that microbursts are likely a significant source of electron loss. Key Points: We use multipoint observations to estimate the size of a long‐lasting microburst‐producing chorus region beginning on 5 December 2017We estimate that the microburst‐producing chorus region for this event extends from 4 to 8 Δ ${\Delta}$MLT and 2–5 Δ ${\Delta}$LMicroburst precipitation from this event likely constitutes a major source of electron loss from the outer radiation belt [ABSTRACT FROM AUTHOR]

This paper presents the highlights of joint observations of the inner magnetosphere by the Arase spacecraft, the Van Allen Probes spacecraft, and ground-based experiments integrated into spacecraft programs. The concurrent operation of the two missions in 2017–2019 facilitated the separation of the spatial and temporal structures of dynamic phenomena occurring in the inner magnetosphere. Because the orbital inclination angle of Arase is larger than that of Van Allen Probes, Arase collected observations at higher L -shells up to L ∼ 10 . After March 2017, similar variations in plasma and waves were detected by Van Allen Probes and Arase. We describe plasma wave observations at longitudinally separated locations in space and geomagnetically-conjugate locations in space and on the ground. The results of instrument intercalibrations between the two missions are also presented. Arase continued its normal operation after the scientific operation of Van Allen Probes completed in October 2019. The combined Van Allen Probes (2012-2019) and Arase (2017-present) observations will cover a full solar cycle. This will be the first comprehensive long-term observation of the inner magnetosphere and radiation belts. [ABSTRACT FROM AUTHOR]

Plasmaspheric hiss can cause energetic electron precipitation from the magnetosphere to the Earth's upper atmosphere and affect the ionospheric electron density profiles. In this study, we use Arase satellite measurements in the dayside plasmasphere to model the electron precipitation and the resultant ionospheric response, and compare the results to the electron density measured by the Poker Flat Incoherent Scatter Radar (PFISR). We analyzed two close conjunction events between Arase and PFISR at L ∼ 6 in the afternoon sector, when Arase was in the outer plasmasphere and traveled into the plasmaspheric plumes. Modest or strong hiss waves were observed with amplitudes higher than 50 pT during both events. Quasilinear modeling suggests that the hiss waves could cause intense electron precipitation ranging from several keV to several hundred keV energies. The electron density profiles at 60–90 km modeled by the Boulder Electron Radiation to Ionization (BERI) model suggest significant electron density enhancements due to the precipitating electrons. PFISR simultaneously observed electron density enhancements during both events, and provided evidence for the electron precipitation at altitudes down to <70 km. The temporal modulation of hiss caused the modulated density profiles in BERI modeling, but was not evident in PFISR observations. The modeled altitude profiles of the perturbed electron density overall agree with PFISR observation. At altitudes below 75 km, the modeled electron densities are lower than the observation, suggesting additional high energy electron precipitation possibly due to low frequency (<50 Hz) waves or hiss wave powers ducted to high latitudes. Key Points: Two Poker Flat Incoherent Scatter Radar (PFISR)‐Arase conjunction events are identified at the dayside plasmasphere when hiss wave amplitudes reach 50–100 pT at L ∼ 6Hiss‐driven electron precipitation obtained from quasilinear simulation is used to model ionospheric density profiles at 60–90 km altitudeModeled electron densities overall agree with PFISR observations with differences in the temporal modulation and at altitudes below 75 km [ABSTRACT FROM AUTHOR]