The Impact of Frailty on Surgical Outcome of Patients with Lumbar Spinal Canal Stenosis

Introduction

Frailty is an important factor in surgical outcomes. The current study aimed to evaluate the effect of preoperative frailty on postoperative outcomes in older patients with lumbar spinal canal stenosis (LSCS).

Methods

We retrospectively examined 209 patients aged ≥65 years who underwent surgery for LSCS. Health-related quality-of-life (HRQOL) tools, including the Roland-Morris Disability Questionnaire (RDQ), Zurich Claudication Questionnaire (ZCQ), and Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ), were used in the assessment conducted before surgery and at 6 months and 1 year after surgery. Frailty was categorized based on the 11-item modified frailty index (mFI-11). Patients with mFI-11 of 0, <0.21, and >0.21 were classified under the robust (R), pre-frailty (P), and frailty (F) groups, respectively.

Results

According to the mFI-11, 24, 138, and 47 patients were included in the R, P, and F groups, respectively. Regarding preoperative radiographic parameters, there was a remarkable increase in the sagittal vertical axis and a significant decrease in the development of lumbar lordosis with frailty progression. The preoperative scores of RDQ and ZCQ, and lumbar function, walking ability, social life, and psychological disorder domain scores of JOABPEQ differed significantly among these groups. The frequency of revision surgery was not higher in the F group than in the other groups. After adjustment for factors have shown different distributions among the three groups, the frequency of effective surgical cases did not show a clear trend among the three groups in all domains of the JOABPEQ.

Conclusions

The preoperative HRQOL scores and the radiographic parameters of patients with LSCS worsened with frailty severity. However, frailty did not affect the rate of revision surgery and surgical efficacy in patients with LSCS. Although this study has limitations, our findings indicated that even LSCS patients with frailty can be considered for surgery if they have an indication for LSCS surgery.

Intradiscal administration of autologous platelet-rich plasma in patients with Modic type 1 associated low back pain: A prospective pilot study

Background

Various treatments for chronic low back pain (LBP) have been reported; among them, platelet-rich plasma (PRP) as a regenerative medicine has attracted much attention. Although Modic type 1 change (MC1) is associated with LBP, no treatment has been established so far. In addition, no studies have administered PRP to intervertebral discs (IVDs) in patients with LBP, targeting MC1 only. Thus, the purpose of this study was to determine the safety and efficacy of PRP administration to the IVDs in patients with MC1 experiencing LBP.

Methods

PRP was injected intradiscally to 10 patients with MC1 experiencing LBP. Patients were followed prospectively for up to 24 weeks after primary administration. Physical condition, laboratory data, and lumbar x-ray images were evaluated for safety assessment. Furthermore, to evaluate the effectiveness of PRP, patient-reported outcomes were considered. In addition, changes in MC1 were assessed using magnetic resonance imaging (MRI).

Results

There were no adverse events in the laboratory data or lumbar X-ray images after administration. The mean visual analog scale, which was 70.0 ± 13.3 before the treatment, significantly decreased 1 week after PRP administration and was 39.0 ± 28.8 at the last observation. Oswestry disability index and Roland Morris disability questionnaire scores promptly improved after treatment, and both improved significantly 24 weeks after PRP administration. Follow-up MRI 24 weeks after treatment showed a significant decrease in the mean high-signal intensity of fat-suppressed T2-weighted imaging from 10.1 to 7.90 mm2 compared with that before PRP administration.

Conclusions

The safety and efficacy of PRP administration to the IVDs of patients with MC1 experiencing LBP were identified. Post-treatment MRI suggested improvement in inflammation, speculating that PRP suppressed inflammation and consequently relieved the patient's symptoms. Despite the small number of patients, this treatment is promising for patients with MC1 experiencing LBP. The study protocol has been reviewed and approved by the Certified Committee for Regenerative Medicine and the Japanese Ministry of Health, Labor and Welfare (Japan Registry of Clinical Trials [jRCT] No. jRCTb042210159).

Nestin-expressing cells are mitotically active in the mammalian inner ear

Nestin expression is associated with pluripotency. Growing evidence suggests nestin is involved in hair cell development. The objective of this study was to investigate the morphology and role of nestin-expressing cells residing in the early postnatal murine inner ear. A lineage-tracing nestin reporter mouse line was used to further characterize these cells. Their cochleae and vestibular organs were immunostained and whole-mounted for cell counting. We found Nestin-expressing cells present in low numbers throughout the inner ear. Three morphotypes were observed: bipolar, unipolar, and globular. Mitotic activity was noted in nestin-expressing cells in the cochlea, utricle, saccule, and crista. Nestin-expressing cell characteristics were then observed after hair cell ablation in two mouse models. First, a reporter model demonstrated nestin expression in a significantly higher proportion of hair cells after hair cell ablation than in control cochleae. However, in a lineage tracing nestin reporter mouse, none of the new hair cells which repopulated the organ of Corti after hair cell ablation expressed nestin, nor did the nestin-expressing cells change in morphotype. In conclusion, Nestin-expressing cells were identified in the cochlea and vestibular organs. After hair cell ablation, nestin-expressing cells did not react to the insult. However, a small number of nestin-expressing cells in all inner ear tissues exhibited mitotic activity, supporting progenitor cell potential, though perhaps not involved in hair cell regeneration.

Significance of Continuous Low-Dose Lenvatinib for the Treating of the Patients with Unresectable Thyroid Carcinoma

The tyrosine kinase inhibitor lenvatinib has been confirmed as an effective treatment option for patients with unresectable thyroid carcinoma. We conducted a retrospective analysis of the significance of the effect of continued lenvatinib treatment for the longest duration possible at a reasonable daily dose and with a minimum discontinuation period in 42 patients with unresectable thyroid carcinoma treated with lenvatinib between 2015 and 2020. A Cox proportional hazard model-based analysis revealed that the overall survival of the patients treated with a <8 mg/day mean dose of lenvatinib was significantly better than that of the patients treated with 8-24 mg/day (hazard ratio [HR] 0.38 for 1.14-4.54 mg/day, and HR 0.01 for 4.56-7.97 mg/day) adjusted for various factors (e.g., sex, age, drug interruption period). The cumulative dose of lenvatinib administered tended to be higher in the patients treated with low doses (< 8 mg/day) than in the patients treated with relatively high doses (8-24 mg/day). Considering its adverse events, the continuation of lenvatinib treatment with an adequate daily dose and drug interruption may help prolong the survival of patients with unresectable thyroid carcinoma.

Association between frailty and locomotive syndrome in elderly patients with lumbar spinal stenosis: A retrospective longitudinal analysis

AIMS

With the aging society worldwide, lumbar spinal stenosis (LSS) has become common, and its incidence has been increasing worldwide. Frailty and locomotive syndrome significantly overlap as disorders in older people. The current study aimed to validate the association between frailty and locomotive syndrome in patients with LSS. In particular, the involvement of frailty in locomotive syndrome following surgery was examined.

METHODS

We retrospectively reviewed the time-course data of consecutive patients aged ≥65 years who underwent lumbar spinal surgery for LSS. The locomotive syndrome stages were determined using the 25-Question Geriatric Locomotive Function Scale: stage 0, score ≤6; stage 1, score ≥7; stage 2, score ≥16; and Stage 3, score ≥24. Robust, pre-frailty, and frailty were defined as a modified frailty index-11 score of 0, <0.21, and >0.21, respectively.

RESULTS

This study included 234 patients. All patients except one were diagnosed with locomotive syndrome preoperatively. Approximately 24.8% of participants were diagnosed with frailty. LSS surgery improved locomotive syndrome regardless of frailty severity. Meanwhile, multivariable analysis indicated that frailty could significantly inhibit improvement in locomotive syndrome after surgery in old patients with LSS (estimated relative risk: 0.6; 95% confidence interval: 0.4-0.9).

CONCLUSIONS

This study first assessed the association between locomotive syndrome and frailty in patients with LSS. Locomotive syndrome could be managed effectively with surgery regardless of frailty severity in old patients with LSS. However, our findings emphasize the need to screen for frailty preoperatively in this patient group. Geriatr Gerontol Int 2024; 24: 116-122.

Spinal Epidural Tuberculoma with Adjacent Vertebral Fracture: A Case Report

CASE

An 85-year-old woman was transported to our institution due to difficulty in walking. Preoperative imaging showed spinal cord lesions indicative of spinal cord tumor at the T7-8 level, accompanied by T8 vertebral fracture. Intraoperatively, the spinal lesion was suspected to be an epidural abscess; therefore, the capsule was resected, and the abscess was drained. We added pedicle screw fixation at the T6-10 level. Postoperatively, the spinal cord lesion was definitively diagnosed as spinal epidural tuberculoma.

CONCLUSION

Spinal epidural tuberculomas should be considered in the treatment of spinal cord lesions causing paralysis attributed to spinal cord compression.

Impact of surgical treatment on lipid metabolism in patients with lumbar spinal disorders: Prospective observational study

PURPOSE

It is still unclear how lumbar spinal surgery affects the lipid metabolism of patients with lumbar spinal disorders (LSDs) such as lumbar spinal canal stenosis and lumbar disk herniation. The present study aimed to assess the impact of lumbar spinal surgery on lipid metabolism in patients with LSDs and clarify the factors associated with changes in visceral fat (VF) accumulation before and after lumbar spinal surgery.

METHODS

Consecutive patients with lumbar spinal surgery for LSDs were prospectively included. Abdominal computed tomography images and blood examination of the participants were evaluated before surgery and at 6 months and 1 year after surgery. The cross-sectional VF area (VFA) was measured at the level of the navel using computed tomography images. Blood examination items included triglycerides and high-density lipoprotein (HDL).

RESULTS

The study enrolled a total of 138 patients. Female patients with LSDs had significantly increased VFA and serum triglyceride levels after lumbar spinal surgery. On multivariable analysis, the group with > 100 cm2 of preoperative VFA and a postoperative decrease in VFA had a significantly worse preoperative walking ability based on the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (relative risk 2.1; 95% confidence intervals 1.1-4.1).

CONCLUSIONS

The present study demonstrated that patients with LSDs did not necessarily improve their lipid metabolism after lumbar spinal surgery. Instead, female patients with LSDs had significantly deteriorated lipid metabolism after lumbar spinal surgery. Finally, a worse preoperative walking ability was associated with the improvement in excess VF accumulation after lumbar spinal surgery.

Circumferential Bone Fusion in Adult Spinal Deformity via Combination of Oblique Lateral Interbody Fusion and Grade 2 Posterior Column Osteotomy

STUDY DESIGN

Retrospective study.

OBJECTIVES

The combination of oblique lateral interbody fusion (OLIF) with grade 2 posterior column osteotomy (PCO) is an effective treatment for adult spinal deformity. However, grade 2 PCO may lead to pseudoarthrosis because it involves complete removal of the bilateral posterior facet joints. The main study objective was to determine the achievement rate of anterior and posterolateral fusion resulting in circumferential fusion in patients who underwent combined OLIF and grade 2 PCO.

METHODS

This retrospective study included consecutive patients who underwent OLIF and grade 2 PCO. The group comprised a long fusion group, with fusion from the thoracic level to the ilium, and a short fusion group, with fusion within the lumbar region. The OLIF with percutaneous pedicle screw insertion group was also used for reference. The Brantigan-Steffee-Fraser classification was used to assess interbody fusion and Lenke classification for assessment of posterolateral fusion.

RESULTS

Sixty-six patients with 109 lumbar levels were included in the study. We observed 100% anterior fusion in all 3 groups. The fusion rate for posterolateral fusion between the OLIF-grade 2 PCO group was 97%, with very low (3%) non-circumferential fusion (pseudoarthrosis only at the osteotomy site). In most cases, solid posterolateral fusions (Lenke A) occurred within 24 months.

CONCLUSIONS

The combination of OLIF and grade 2 PCO resulted in circumferential fusion for most (97%) of the cases within 24 months. OLIF and grade 2 PCO are considered a good combination treatment to achieve sufficient lumbar lordosis and solid bone fusion.

Elucidation of the Mechanism of Occasional Anterior Longitudinal Ligament Rupture with Posterior Correction Procedure for Adult Spinal Deformity Using LLIF-Finite Element Analysis of the Impact of the Lordotic Angle of Intervertebral LLIF Cage

Background and Objectives: There are several advantages of using lateral lumbar interbody fusion (LLIF) for correction surgeries for adult spinal deformity (ASD); however, we currently have unresolved new issues, including occasional anterior longitudinal ligament (ALL) rupture during the posterior correction procedure. When LLIF was initially introduced, only less lordotic cages were available and ALL rupture was more frequently experienced compared with later periods when more lordotic cages were available. We performed finite element analysis (FEA) regarding the mechanism of ALL rupture during a posterior correction procedure. Methods: A spring (which mimics ALL) was introduced at the location of ALL in the FEA and an LLIF cage with two different lordotic angles, 6 and 12 degrees (6DC/12DC), was employed. To assess the extent of burden on the ALL, the extension length of the spring during the correction procedure was measured and the location of the rotation center was examined. Results: We observed a significantly higher degree of length extension of the spring during the correction procedure in the FEA model with 6DC compared with that of 12DC. We also observed that the location of the rotation center was shifted posteriorly in the FEA model with 6DC compared with that of 12DC. Conclusions: It is considered that the posterior and rostral edge of the less lordotic angle cage became a hinge, and the longer lever arm increased the burden on ALL as the principle of leverage. It is important to use an LLIF cage with a sufficient lordotic angle, that is compatible with the degree of posterior osteotomy in ASD correction.

Severity of locomotive syndrome in surgical cervical spondylotic myelopathy patients: a cross-sectional study

OBJECTIVES

Although cervical spondylotic myelopathy (CSM) has a marked impact on locomotive function, few studies have evaluated this relationship in terms of locomotive syndrome. Thus, we assessed (i) the stages of locomotive syndrome in preoperative CSM patients using the 25-question geriatric locomotive function scale (GLFS-25), (ii) the correlation between GLFS-25 scores and the Japanese orthopaedic association (JOA) scores or the JOA cervical myelopathy evaluation questionnaire (JOACMEQ) scores, and (iii) the factors associated with stage 3 locomotive syndrome in preoperative CSM patients.

METHODS

We used clinical data from 107 patients scheduled for cervical spinal surgery for CSM. Data were collected prior to surgery, and included age, gender, body mass index, medical history, JOA score, and JOACMEQ and GLFS-25 scores.

RESULTS

Of the included CSM patients, 93.5% were diagnosed with locomotive syndrome, of whom 77.6% were stage 3 according to GLFS-25 evaluation. For the correlation between GLFS-25 and JOA or JOACMEQ, the upper and lower extremity function scores of JOACMEQ and the JOA were strongly inversely correlated with the GLFS-25 score. Finally, multivariate analysis suggested that severe lower extremity status in the JOACMEQ was significantly associated with stage 3 locomotive syndrome in preoperative CSM patients.

CONCLUSIONS

Using the GLFS-25, we found that lower extremity status had the strongest association with stage 3 locomotive syndrome in preoperative CSM patients. These findings are useful for preventing CSM patients from requiring future nursing care.

Different solubilizing ability of cyclodextrin derivatives for cholesterol in Niemann-Pick disease type C treatment

BACKGROUND

Niemann-Pick disease type C (NPC) is a fatal neurodegenerative disorder caused by abnormal intracellular cholesterol trafficking. Cyclodextrins (CDs), the most promising therapeutic candidates for NPC, but with concerns about ototoxicity, are cyclic oligosaccharides with dual functions of unesterified cholesterol (UC) shuttle and sink that catalytically enhance the bidirectional flux and net efflux of UC, respectively, between the cell membrane and the extracellular acceptors. However, the properties of CDs that regulate these functions and how they could be used to improve treatments for NPC are unclear.

METHODS

We estimated CD-UC complexation for nine CD derivatives derived from native α-, β-, and γ-CD with different cavity sizes, using solubility and molecular docking analyses. The stoichiometry and complexation ability of the resulting complexes were investigated in relation to the therapeutic effectiveness and toxicity of each CD derivative in NPC experimental models.

FINDINGS

We found that shuttle and sink activities of CDs are dependent on cavity size-dependent stoichiometry and substituent-associated stability of CD-UC complexation. The ability of CD derivatives to form 1:1 and 2:1 complexes with UC were correlated with their ability to normalize intracellular cholesterol trafficking serving as shuttle and with their cytotoxicity associated with cellular UC efflux acting as sink, respectively, in NPC model cells. Notably, the ability of CD derivatives to form an inclusion complex with UC was responsible for not only efficacy but ototoxicity, while a representative derivative without this ability negligibly affected auditory function, underscoring its preventability.

CONCLUSIONS

Our findings highlight the importance of strategies for optimizing the molecular structure of CDs to overcome this functional dilemma in the treatment of NPC.

Influence of the concentrate inclusion level in a grass silage-based diet on hepatic transcriptomic profiles in Holstein-Friesian dairy cows in early lactation

Excessive negative energy balance in early lactation is linked to an increased disease risk but may be mitigated by appropriate nutrition. The liver plays central roles in both metabolism and immunity. Hepatic transcriptomic profiles were compared between 3 dietary groups in each of 40 multiparous and 18 primiparous Holstein-Friesian cows offered isonitrogenous grass silage-based diets with different proportions of concentrates: (1) low concentrate (LC, 30% concentrate + 70% grass silage); (2) medium concentrate (MC, 50% concentrate + 50% grass silage), or (3) high concentrate (HC, 70% concentrate + 30% grass silage). Liver biopsies were taken from all cows at around 14 d in milk for RNA sequencing, and blood metabolites were measured. The sequencing data were analyzed separately for primiparous and multiparous cows using CLC Genomics Workbench V21 (Qiagen Digital Insights), focusing on comparisons between HC and LC groups. More differentially expressed genes (DEG) were seen between the primiparous cows receiving HC versus LC diets than for multiparous cows (597 vs. 497), with only 73 in common, indicating differential dietary responses. Multiparous cows receiving the HC diet had significantly higher circulating glucose and insulin-like growth factor-1 and lower urea than those receiving the LC diet. In response to HC, only the multiparous cows produced more milk. In these animals, bioinformatic analysis indicated expression changes in genes regulating fatty acid metabolism and biosynthesis (e.g., ACACA, ELOVL6, FADS2), increased cholesterol biosynthesis (e.g., CYP7A1, FDPS, HMGCR), downregulation in hepatic AA synthesis (e.g., GPT, GCLC, PSPH, SHMT2), and decreased expression of acute phase proteins (e.g., HP, LBP, SAA2). The primiparous cows on the HC diet also downregulated genes controlling AA metabolism and synthesis (e.g., CTH, GCLC, GOT1, ODC1, SHMT2) but showed higher expression of genes indicative of inflammation (e.g., CCDC80, IL1B, S100A8) and fibrosis (e.g., LOX, LUM, PLOD2). This potentially adverse response to a HC diet in physically immature animals warrants further investigation.

Efficacy of surgical treatment on polypharmacy of elderly patients with lumbar spinal canal stenosis: retrospective exploratory research

BACKGROUND

Polypharmacy is a growing public health problem occurring in all healthcare settings worldwide. Elderly patients with lumbar spinal canal stenosis (LSS) who manifest low back and neuropathic pain and have a high frequency of comorbidity are predicted to take many drugs. However, no studies have reported polypharmacy in elderly patients with LSS. Thus, we aimed to review the polypharmacy among elderly LSS patients with elective surgeries and examine how the surgical treatment reduces the polypharmacy.

METHODS

We retrospectively enrolled all the patients aged ≥ 65 years who underwent spinal surgery for LSS between April 2020 and March 2021. The prescribed drugs of participants were directly checked by pharmacists in the outpatient department preoperatively and 6-month and 1-year postoperatively. The baseline characteristics were collected beside the patient-based outcomes including Roland-Morris Disability Questionnaire, Zurich Claudication Questionnaire, and Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ). The cutoff number of drugs for polypharmacy was defined as 6. The prescription drugs were divided into 9 categories: drugs for neuropsychiatric, cardiovascular, respiratory, digestive, endocrine metabolic, and urinary renal diseases; blood products; pain relief medication; and others.

RESULTS

A total of 102 cases were finally analyzed, with a follow-up rate of 78.0%. Of the participants, the preoperative polypharmacy prevalence was 66.7%. The number of drugs 6-month and 1-year postoperatively was significantly less than the preoperative one. The proportions of polypharmacy at 6 months and 1 year after surgery significantly decreased to 57.8% and 55.9%, respectively. When the prescribed drugs were divided into 9 categories, the number of drugs for pain relief and digestive diseases was significantly reduced after surgery. The multi-variable analysis revealed that a higher score in the psychological disorder of JOABPEQ was associated with 3 or more drugs decreased 1-year postoperatively (OR, 2.5; 95% CI: 1.0-6.1).

CONCLUSION

Polypharmacy prevalence was high among elderly LSS patients indicated for lumbar spinal surgery. Additionally, our data showed that lumbar spinal surgery was effective in reducing polypharmacy among elderly LSS patients. Finally, the multi-variable analysis indicated that better psychological condition was associated with the reduction of prescribed drugs after lumbar spinal surgery.

Impact of Lumbar Surgery on Pharmacological Treatment for Patients with Lumbar Spinal Canal Stenosis: A Single-Center Retrospective Study

Treatment for lumbar spinal canal stenosis (LSCS) is mainly classified into conservative and surgical therapies. Among conservative therapies, pharmacological treatment is commonly prescribed for LSCS. Meanwhile, surgical treatment is the last option for LSCS. This study aimed to examine the impact of lumbar surgery on pharmacological treatment for patients with LSCS. Consecutive patients aged ≥ 40 years who underwent lumbar surgery for LSCS were identified. A total of 142 patients were retrospectively reviewed for preoperative and 6-month and 1-year postoperative LSCS medications. The results showed that the number of LSCS medications significantly decreased after lumbar surgery. The proportion of the patients taking non-steroidal anti-inflammatory drugs, pregabalin/mirogabalin, opioids, prostaglandin E1 analogs, and neurotropin was significantly decreased after lumbar surgery, but that of the patients taking mecobalamin, acetaminophen, and serotonin-noradrenalin reuptake inhibitors was not significantly changed. Additionally, around 15% of the participants showed an increase in LSCS medications even after lumbar surgery. Multivariable analysis revealed that individuals without improvements in walking ability (RR: 2.7, 95% CI: 1.3-5.9) or social life (RR: 2.3, 95% CI: 1.1-5.0) had a greater risk of a postoperative increase in LSCS medications. The study results may provide physicians with beneficial information on treatment for LSCS.

Potential Involvement of Oxidative Stress in Ligamentum Flavum Hypertrophy

Oxidative stress (OS) results in many disorders, of which degenerative musculoskeletal conditions are no exception. However, the interaction between OS and ligamentum flavum (LF) hypertrophy in lumbar spinal canal stenosis is not clearly understood. The first research question was whether OS was involved in LF hypertrophy, and the second was whether the antioxidant N-acetylcysteine (NAC) was effective on LF hypertrophy. In total, 47 LF samples were collected from patients with lumbar spinal disorders. The cross-sectional area of LF was measured on axial magnetic resonance imaging. Immunohistochemistry of 8-OHdG and TNF-α were conducted on human LF samples. A positive association was found between 8-OHdG or TNF-α expression and cross-sectional area of LF. Flow cytometry analysis showed that H₂O₂, buthionine sulfoximine, and TNF-α treatment significantly increased intracellular reactive oxygen species in primary LF cells. NAC inhibited the induction of LF hypertrophy markers by OS or TNF in a real-time reverse transcriptase polymerase chain reaction and enzyme-linked immunosorbent assay. Western blotting analysis indicated that p38, Erk, and p65 phosphorylation were involved in intracellular OS signaling in LF cells. In conclusion, our results indicated that OS could be a therapeutic target for LF hypertrophy. Although this study included no in vivo studies to examine the longitudinal efficacy of NAC on LF hypertrophy, NAC may have potential as a therapeutic agent against lumbar spinal canal stenosis.

Clinical and laboratory characteristics of complex febrile seizures in the acute phase: a case-series study in Japan

BACKGROUND

Patients with complex febrile seizures (CFS) often display abnormal laboratory results, unexpectedly prolonged seizures, and/or altered consciousness after admission. However, no standardized values have been established for the clinical and laboratory characteristics of CFS in the acute phase, making the management of CFS challenging. This study aimed to determine the clinical and laboratory characteristics of children with CFS during the acute phase. In particular, the duration of impaired consciousness and the detailed distribution of blood test values were focused.

METHODS

We retrospectively reviewed medical records of a consecutive pediatric cohort aged 6-60 months who were diagnosed with CFS and admitted to Kobe Children's Hospital between October 2002 and March 2017. During the study period, 486 seizure episodes with confirmed CFS were initially reviewed, with 317 seizure episodes included in the analysis. Detailed clinical and laboratory characteristics were summarized.

RESULTS

Among 317 seizure episodes (296 children with CFS), 302 required two or fewer anticonvulsants to be terminated. In 296 episodes showing convulsive seizures, median seizure duration was 30.5 min. The median time from onset to consciousness recovery was 175 min. Impaired consciousness lasting > 6, 8, and 12 h was observed in 13.9%, 7.6%, and 1.9% patients with CFS, respectively. Additionally, the distribution of aspartate aminotransferase, lactate dehydrogenase, creatinine, and glucose were clarified with 3, 10, 50, 90, and 97 percentile values.

CONCLUSION

This study detailed the clinical and laboratory findings of acute-phase CFS using the data of the largest 15-year consecutive cohort of children with CFS. These results provide important information for appropriate acute management of CFS.

Outpatient ablation treatment with two doses of 30 mCi of radioactive iodine for non-low-risk papillary thyroid cancer

Outpatient ablation therapy with low-dose radioactive iodine (RAI) is applied to non-low-risk papillary thyroid cancer patients due to a chronic shortage of inpatient RAI treatment wards in Japan. We used the maximum dosage available for outpatient therapy of 30 mCi of RAI for ablation and diagnostic (Dx) whole-body scintigraphy (WBS). This study aimed to examine the significance of the second dose of 30 mCi. DxWBS was performed 6 months after ablation, and assessment of success or failure was performed 12 months after ablation. A second WBS was performed in the remaining RAI accumulation cases in the neck on DxWBS. The criteria for successful ablation was negative cervical accumulation on WBS, thyroid stimulating hormone-suppressed thyroglobulin (sup-Tg) below 1.0 ng?/?mL, and no increase in thyroglobulin antibody (TgAb) level. At the time of DxWBS, 35?/?68 cases met the successful criteria, and 45 cases achieved success at assessment. Sup-Tg values decreased significantly after ablation and decreased further after DxWBS in successful ablation cases, whereas those were not changed in ablation failure cases. Findings indicated that RAI used in DxWBS had therapeutic effects. It makes sense to use 30 mCi for DxWBS, given the current difficulty of inpatient ablation therapy with high-dose RAI. J. Med. Invest. 70 : 17-21, February, 2023.

Repeated Recurrence of Ligamentum Flavum Ossification After Posterior Spinal Surgery: A Case Report and Literature Review

CASE

Patients with myelopathy due to narrowing of the spinal canal with ossification of the ligamentum flavum (OLF) generally require surgical intervention, but surgical methods for OLF remain controversial. We discuss our experience regarding posterior fusion surgery with instrumentation for a patient with recurrent OLF at the same level after decompression surgery as well as describe the preoperative and postoperative course of this rare case.

CONCLUSION

Posterior decompression and fusion surgery is recommended as revision surgery for recurrent OLF at the same level after decompression surgery. A detailed surgical planning should be developed before surgery.

Targeted single-cell genomics reveals novel host adaptation strategies of the symbiotic bacteria Endozoicomonas in Acropora tenuis coral

BACKGROUND

Endozoicomonas bacteria symbiosis with various marine organisms is hypothesized as a potential indicator of health in corals. Although many amplicon analyses using 16S rRNA gene have suggested the diversity of Endozoicomonas species, genome analysis has been limited due to contamination of host-derived sequences and difficulties in culture and metagenomic analysis. Therefore, the evolutionary and functional potential of individual Endozoicomonas species symbiotic with the same coral species remains unresolved.

RESULTS

In this study, we applied a novel single-cell genomics technique using droplet microfluidics to obtain single-cell amplified genomes (SAGs) for uncultured coral-associated Endozoicomonas spp. We obtained seven novel Endozoicomonas genomes and quantitative bacterial composition from Acropora tenuis corals at four sites in Japan. Our quantitative 16S rRNA gene and comparative genomic analysis revealed that these Endozoicomonas spp. belong to different lineages (Clade A and Clade B), with widely varying abundance among individual corals. Furthermore, each Endozoicomonas species possessed various eukaryotic-like genes in clade-specific genes. It was suggested that these eukaryotic-like genes might have a potential ability of different functions in each clade, such as infection of the host coral or suppression of host immune pathways. These Endozoicomonas species may have adopted different host adaptation strategies despite living symbiotically on the same coral.

CONCLUSIONS

This study suggests that coral-associated Endozoicomonas spp. on the same species of coral have different evolutional strategies and functional potentials in each species and emphasizes the need to analyze the genome of each uncultured strain in future coral-Endozoicomonas relationships studies. Video Abstract.

Discovery of ^{39}Na

The new isotope ^{39}Na, the most neutron-rich sodium nucleus observed so far, was discovered at the RIKEN Nishina Center Radioactive Isotope Beam Factory using the projectile fragmentation of an intense ^{48}Ca beam at 345  MeV/nucleon on a beryllium target. Projectile fragments were separated and identified in flight with the large-acceptance two-stage separator BigRIPS. Nine ^{39}Na events have been unambiguously observed in this work and clearly establish the particle stability of ^{39}Na. Furthermore, the lack of observation of ^{35,36}Ne isotopes in this experiment significantly improves the overall confidence that ^{34}Ne is the neutron dripline nucleus of neon. These results provide new key information to understand nuclear binding and nuclear structure under extremely neutron-rich conditions. The newly established stability of ^{39}Na has a significant impact on nuclear models and theories predicting the neutron dripline and also provides a key to understanding the nuclear shell property of ^{39}Na at the neutron number N=28, which is normally a magic number.

β-Delayed One and Two Neutron Emission Probabilities Southeast of ^{132}Sn and the Odd-Even Systematics in r-Process Nuclide Abundances

The β-delayed one- and two-neutron emission probabilities (P_{1n} and P_{2n}) of 20 neutron-rich nuclei with N≥82 have been measured at the RIBF facility of the RIKEN Nishina Center. P_{1n} of ^{130,131}Ag, ^{133,134}Cd, ^{135,136}In, and ^{138,139}Sn were determined for the first time, and stringent upper limits were placed on P_{2n} for nearly all cases. β-delayed two-neutron emission (β2n) was unambiguously identified in ^{133}Cd and ^{135,136}In, and their P_{2n} were measured. Weak β2n was also detected from ^{137,138}Sn. Our results highlight the effect of the N=82 and Z=50 shell closures on β-delayed neutron emission probability and provide stringent benchmarks for newly developed macroscopic-microscopic and self-consistent global models with the inclusion of a statistical treatment of neutron and γ emission. The impact of our measurements on r-process nucleosynthesis was studied in a neutron star merger scenario. Our P_{1n} and P_{2n} have a direct impact on the odd-even staggering of the final abundance, improving the agreement between calculated and observed Solar System abundances. The odd isotope fraction of Ba in r-process-enhanced (r-II) stars is also better reproduced using our new data.

Fine-tuned cholesterol solubilizer, mono-6-O-α-D-maltosyl-γ-cyclodextrin, ameliorates experimental Niemann-Pick disease type C without hearing loss

Niemann-Pick disease type C (NPC) is a fatal disorder with abnormal intracellular cholesterol trafficking resulting in neurodegeneration and hepatosplenomegaly. A cyclic heptasaccharide with different degrees of substitution of 2-hydroxypropyl groups, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD), acts as a strong cholesterol solubilizer and is under investigation for treating this disease in clinical trials, but its physicochemical properties and ototoxicity remain a concern. Here, we evaluated the potential of mono-6-O-α-maltosyl-γ-CD (G2-γ-CD), a single-maltose-branched cyclic octasaccharide with a larger cavity than HP-β-CD, for treating NPC. We identified that G2-γ-CD ameliorated NPC manifestations in model mice and showed lower ototoxicity in mice than HP-β-CD. To investigate the molecular mechanisms of action behind the differential ototoxicity of these CDs, we performed cholesterol solubility analysis, proton nuclear magnetic resonance spectroscopy, and molecular modeling, and estimated that the cholesterol inclusion mode of G2-γ-CD maintained solely the 1:1 inclusion complex, whereas that of HP-β-CD shifted to the highly-soluble 2:1 complex at higher concentrations. We predicted the associations of these differential complexations of CDs with cholesterol with the profile of disease attenuation and of the auditory cell toxicity using specific cell models. We proposed that G2-γ-CD can serve as a fine-tuned cholesterol solubilizer for treating NPC, being highly biocompatible and physicochemically suitable for clinical application.

Recurrent Iliopsoas Abscesses Due to Migrated Appendicular Fecalith: A Case Report and Review of the Literature

CASE

Appendicular fecaliths have been reported to migrate to nearby organs before or during surgical treatment and become a late source of infection. We report an extremely rare case of recurrent iliopsoas abscesses caused by appendicular fecaliths that have migrated to the psoas muscle before or during the previous appendicectomy for acute appendicitis. In this case, surgical removal of fecaliths cured the iliopsoas abscess.

CONCLUSION

Orthopaedic surgeons and gastroenterologists should remember that appendicular fecaliths that migrated into the iliopsoas muscle may cause late-onset iliopsoas abscesses.

First Application of Mass Measurements with the Rare-RI Ring Reveals the Solar r-Process Abundance Trend at A=122 and A=123

The Rare-RI Ring (R3) is a recently commissioned cyclotronlike storage ring mass spectrometer dedicated to mass measurements of exotic nuclei far from stability at Radioactive Isotope Beam Factory (RIBF) in RIKEN. The first application of mass measurement using the R3 mass spectrometer at RIBF is reported. Rare isotopes produced at RIBF-^{127}Sn, ^{126}In, ^{125}Cd, ^{124}Ag, ^{123}Pd-were injected in R3. Masses of ^{126}In, ^{125}Cd, and ^{123}Pd were measured whereby the mass uncertainty of ^{123}Pd was improved. This is the first reported measurement with a new storage ring mass spectrometry technique realized at a heavy-ion cyclotron and employing individual injection of the preidentified rare nuclei. The latter is essential for the future mass measurements of the rarest isotopes produced at RIBF. The impact of the new ^{123}Pd result on the solar r-process abundances in a neutron star merger event is investigated by performing reaction network calculations of 20 trajectories with varying electron fraction Y_{e}. It is found that the neutron capture cross section on ^{123}Pd increases by a factor of 2.2 and β-delayed neutron emission probability, P_{1  n}, of ^{123}Rh increases by 14%. The neutron capture cross section on ^{122}Pd decreases by a factor of 2.6 leading to pileup of material at A=122, thus reproducing the trend of the solar r-process abundances. The trend of the two-neutron separation energies (S_{2n}) was investigated for the Pd isotopic chain. The new mass measurement with improved uncertainty excludes large changes of the S_{2n} value at N=77. Such large increase of the S_{2n} values before N=82 was proposed as an alternative to the quenching of the N=82 shell gap to reproduce r-process abundances in the mass region of A=112-124.

A case of a young boy with hyper-fibrinolysis associated with natural fibrin precipitates suspected to have occurred through a novel coagulation and fibrinolysis mechanism

An 8-year-old Japanese boy with no underlying disease presented with severe intramuscular hematoma of the hip, and was admitted for a disseminated intravascular coagulation-like state with fibrinolytic dominance. Laboratory examinations revealed severe hyper-fibrinolysis with elevated markers, markedly shortened euglobulin clot lysis time, mildly decreased prothrombin, and severely decreased fibrinogen and factor XIII. Natural fibrin precipitates rapidly appeared in citrate-treated, ethylene-diamine-tetra-acetic-treated, and heparin-treated samples, but not in argatroban-treated samples, indicating that the mechanism of thrombin and fibrin formation was Ca²⁺-independent. The precipitates were physically similar to thrombin-triggered plasma fibrin. A global coagulation assay revealed that thrombin generation potentials were normal throughout the clinical course, whereas plasmin generation was already detected before initiation of fibrin formation in the acute phase. This phenomenon disappeared with time. Changes in coagulation abnormalities and nature of fibrinolysis paralleled those seen in specific markers for streptococcal infections. Streptokinase was possibly involved in this disease, as SDS-polyacrylamide gel electrophoresis revealed that plasmin derived from streptokinase-plasminogen complex proteolyzed the prothrombin to approximately 35-kDa α-thrombin consisting of the A-B single chain, which was identified by NH₂-terminal sequence analysis. The involvement of streptokinase-plasminogen-prothrombin caused by streptococcal infection may be one mechanism that produces marked hyper-fibrinolysis associated with natural fibrin precipitates.

Favorable response to pembrolizumab in granulocyte colony-stimulating factor-producing upper urinary tract urothelial carcinoma

Introduction

Granulocyte colony‐stimulating factor‐producing upper urinary tract urothelial carcinoma is rare, with a poor prognosis. Advanced urothelial carcinoma is currently treated with immune checkpoint inhibitors, whose efficacy for granulocyte colony‐stimulating factor‐producing upper urinary tract urothelial carcinoma remains unclear.

Case presentation

A 66‐year‐old male diagnosed with clinical stage T3N1M0 urothelial carcinoma of the right ureter with giant hydronephrosis underwent right radical nephroureterectomy. Local recurrence, leukocytosis, and elevated serum granulocyte colony‐stimulating factor levels were observed approximately 3 months after surgery. Chemotherapy was started but failed to control the disease. Therefore, pembrolizumab was chosen as the second‐line treatment. After this treatment, the blood leukocyte count rapidly normalized, and a clinically favorable response was achieved. There was no recurrence 10 months after the beginning of pembrolizumab treatment, which is still ongoing.

Conclusion

Pembrolizumab may be a treatment option for advanced granulocyte colony‐stimulating factor‐producing upper urinary tract urothelial carcinoma.

Utility of intraoperative real-time near-infrared fluorescence surgery for spinal schwannoma

The authors report the first cases of fluorescence-guided spinal surgery of schwannomas using near-infrared fluorescence imaging with the delayed window indocyanine (ICG) green (DWIG) technique for accurate real-time intraoperative tumor visualization.

Patients with intradural spinal schwannomas received 0.5 mg/kg ICG at the beginning of surgery. After 1 hour, using the DWIG technique, near-infrared spectroscopy (NIRS) detected the spinal schwannomas, showing the exact tumor location and boundaries. DWIG with NIRS microscopy confirmed the exact location of spinal schwannomas before and after opening of the dura mater, thereby facilitating successful tumor dissection from the surrounding tissues, tumor resection, and confirmation of tumor removal.

The video can be found here: https://stream.cadmore.media/r10.3171/2021.10.FOCVID21158

Bone wax technique for full-endoscopic lumbar laminotomy

Hemostatic procedures in endoscopic spine surgery have not yet been established, especially in full-endoscopic spine surgery (FESS) performed under continuous irrigation, which has been a major concern for surgeons. Chu et al. had previously reported a technique to convey bone wax during full-endoscopic cervical spine surgery via intracorporeal route by using ball tip of the drill in 2018. However, to the best of our knowledge, there has been no report by surgeons to adopt bone wax as a hemostatic material in full-endoscopic lumbar surgery to date, probably because of difficulty in handling bone wax under continuous irrigation and through a narrow and long working channel in endoscope. We have renewed the bone wax technique (BWT) for hemostasis in FESS, improving its handling by introducing a nozzle applicator, without which the bone wax would stick to the working channel of the endoscope on the way to the bleeding target. This would result in significant loss of bone wax and repeated bone-wax contact would cause dirt build-up on the endoscope lens, which would then be pushed out from the wall of the working channel, thereby disturbing the laminectomy procedure and obfuscating the visual field. Technical details using nozzle-loaded bone wax have been demonstrated.

Impact of the State of Emergency during the COVID-19 Pandemic in 2020 on Asthma Exacerbations among Children in Kobe City, Japan

The coronavirus disease (COVID-19) pandemic altered environmental factors. We studied the impact of these changes on asthma exacerbation (AE) by comparing the AE-related environmental factors between COVID-19 (2020) and pre-COVID-19 (2011–2019) eras. Between 2011 and 2020, 278,465 children (<16 years old) visited our emergency department, and 7476 were diagnosed with AE. The number of patients showed spring and fall peaks in 2011–2019. Multivariate analyses showed significant positive relationships of the number of AE patients with the average temperature among all patients and 0–5-year-olds and with sulfur dioxide (SO₂) levels in 2011–2019 among 0–5-year-olds. Although the spring peak in the number of patients was not observed in 2020 after declaration of a state of emergency, the fall peak was again observed after the state of emergency was lifted. No changes in average temperature were detected, but SO₂ was significantly reduced following declaration of the state of emergency in 2020. Therefore, SO₂ reduction might have contributed to the disappearance of the peak of AE. However, a fall peak was observed again in 2020, although SO₂ levels continued to be low. These data suggest that person to person interaction seems to be associated with AE, presumably due to unknown viral infections.

Current management for foreign body and toxic agent ingestion in a paediatric primary emergency centre

OBJECTIVES

Accidental foreign body ingestion (FBI) and toxic agent ingestion (TAI) are commonly encountered among children in primary emergency settings. Early detection and appropriate medical intervention are crucial to improve outcomes. Although many reports from tertiary institutions have shown improvements in therapy, data are still lacking from primary emergency facilities.

METHODS

We performed a retrospective analysis based on medical records of FBI/TAI over 4 years at the Kobe Children's Primary Emergency Medical Center. We collected patient information, including age, sex, time between FBI/TAI occurrence and centre visit, provision of first aid, symptoms, type of FBI/TAI, examinations, treatments, and outcomes.

RESULTS

A total of 580 children were enrolled. The median age was 1.3 years, and patients under 2 years old accounted for 70% of total cases. Cigarettes (17.5%) were the most common ingested foreign body, followed by medicines (15.3%), detergents (8.1%), in TAI, plastics (14.1%), metal (13.4%), batteries (9.0%) in FBI, and others (22.6%). A total of 42 patients were transferred to advanced hospitals; among these, 22 patients were hospitalised but the foreign body was removed in only 3 (0.9%) patients. Transferred patients were significantly older (P<0.05) in FBI and had a higher rate of any of symptoms (P<0.05) in FBI/TAI.

CONCLUSIONS

This large-scale retrospective study of accidental FBI/TAI conducted at a primary emergency facility clarified current management, including treatment at a primary facility. Very few cases of FBI/TAI were treated, even when they were transferred to an advanced treatment hospital. Unified protocols should be established, to improve the management of FBI/TAI.

Prevalence of Wilson disease based on genome databases in Japan

BACKGROUND

Wilson disease (WD) is an autosomal recessive disorder caused by mutations in the ATP7B gene. In 1984, Scheinberg and Sternlieb estimated the prevalence of WD to be 1:30 000. However, recent epidemiological studies have reported increasing prevalence rates in different populations. The carrier frequency of ATP7B variants and the prevalence of WD in the Japanese population have not been reported using multiple databases.

METHODS

Multiple public databases were used. First, we included mutations in the ATP7B gene that were registered in the Human Gene Mutation Database (HGMD) Professional, where 885 ATP7B variants were identified as pathogenic. Next, we investigated the allele frequencies of these 885 variants in Japanese individuals using the Human Genetic Variation Database (HGVD) and the Japanese Multi Omics Reference Panel (jMorp).

RESULTS

Of the 885 variants of ATP7B, 7 and 12 missense and nonsense variants, zero and three splicing variants, and zero and two small deletions were found in the HGVD and in jMorp, respectively. The total allele frequencies of the ATP7B mutations were 0.011 in the HGVD and 0.014 in the jMorp. According to these data, the carrier frequencies were 0.022 (2.2%) and 0.028 (2.8%), respectively, and patient frequencies were 0.000121 (1.21/10 000 individuals) and 0.000196 (1.96/10 000 individuals), respectively.

CONCLUSIONS

This is the first study to report the carrier frequency of ATP7B variants and the prevalence of WD in Japan using multiple databases. The calculated prevalence of WD was comparatively higher than that of previous reports, indicating previous underdiagnosis or the existence of less severe phenotypes.

Early steroid pulse therapy for children with suspected acute encephalopathy: An observational study

Steroid pulse therapy is widely used to treat virus-associated acute encephalopathy, especially the cytokine storm type; however, its effectiveness remains unknown. We sought to investigate the effectiveness of early steroid pulse therapy for suspected acute encephalopathy in the presence of elevated aspartate aminotransferase (AST) levels.We enrolled children admitted to Hyogo Children's Hospital between 2003 and 2017 with convulsions or impaired consciousness accompanied by fever (temperature >38°C). The inclusion criteria were: refractory status epilepticus or prolonged neurological abnormality or hemiplegia at 6 hours from onset, and AST elevation >90 IU/L within 6 hours of onset. We excluded patients with a neurological history. We compared the prognosis between the groups with or without steroid pulse therapy within 24 hours. A good prognosis was defined as a Pediatric Cerebral Performance Category Scale (PCPC) score of 1-2 at the last evaluation, within 30 months of onset. Moreover, we analyzed the relationship between prognosis and time from onset to steroid pulse therapy.Fifteen patients with acute encephalopathy and 5 patients with febrile seizures were included in this study. Thirteen patients received steroid pulse therapy within 24 hours. There was no between-group difference in the proportion with a good prognosis. There was no significant correlation between PCPC and timing of steroid pulse therapy (rs = 0.253, P = .405). Even after excluding 2 patients with brainstem lesions, no significant correlation between PCPC and steroid pulse therapy timing (rs = 0.583, P = .060) was noted. However, the prognosis tended to be better in patients who received steroid pulse therapy earlier.Steroid pulse therapy within 24 hours did not improve the prognosis in children with suspected acute encephalopathy associated with elevated AST. Still, even earlier administration of treatment could prevent the possible neurological sequelae of this condition.

Collagen profiling of ligamentum flavum in patients with lumbar spinal canal stenosis

BACKGROUND

Although several causes of ligamentum flavum (LF) hypertrophy have been identified, the pathomechanisms underlying LF hypertrophy are not fully understood. Because collagen fibers are essential for the maintenance of LF tissues, characterization of the collagen composition of hypertrophied LF may help to elucidate the pathology of lumbar spinal canal stenosis (LCS). This study aimed to determine the association between the collagen composition and LF hypertrophy.

METHODS

LF tissues were collected from 23 patients who underwent spinal decompression surgery for lumbar disorders. The cross-sectional area of LF was measured using the axial images of lumbar MRI. The expression of each collagen in human surgical samples was evaluated by real-time RT-PCR and immunohistochemical analysis. To investigate the impact of inflammatory cytokines on the expression of each collagen, we treated primary human LF cells with TNF-α or IL-1β.

RESULTS

Real-time RT-PCR analysis and immunohistochemistry showed that of the 28 types of collagen, collagen type I, III, V, VI, VIII were highly expressed regardless of LF hypertrophy. In addition, we found the moderate correlation between the cross-sectional area of LF and the mRNA expression level of collagen type I, III, and VI. In vitro analysis showed that the mRNA expression of collagen type I, III, V, VI, and VIII was up-regulated by treatment with TNF-α and with IL-1β.

CONCLUSION

Our results suggested that collagen type I, III, V, VI, and VIII were the main components of the LF extracellular matrix and that collagen type I, III, and VI may serve as useful markers of LF hypertrophy. These findings may contribute to the future development of diagnostic and treatment modalities for LF hypertrophy and even LCS.

Selective ablation of cochlear hair cells promotes engraftment of human embryonic stem cell-derived progenitors in the mouse organ of Corti

BACKGROUND

Hearing loss affects 25% of the population at ages 60-69 years. Loss of the hair cells of the inner ear commonly underlies deafness and once lost this cell type cannot spontaneously regenerate in higher vertebrates. As a result, there is a need for the development of regenerative strategies to replace hair cells once lost. Stem cell-based therapies are one such strategy and offer promise for cell replacement in a variety of tissues. A number of investigators have previously demonstrated successful implantation, and certain level of regeneration of hair and supporting cells in both avian and mammalian models using rodent pluripotent stem cells. However, the ability of human stem cells to engraft and generate differentiated cell types in the inner ear is not well understood.

METHODS

We differentiate human pluripotent stem cells to the pre-placodal stage in vitro then transplant them into the mouse cochlea after selective and complete lesioning of the endogenous population of hair cells.

RESULTS

We demonstrate that hair cell ablation prior to transplantation leads to increased engraftment in the auditory sensory epithelium, the organ of Corti, as well as differentiation of transplanted cells into hair and supporting cell immunophenotypes.

CONCLUSION

We have demonstrated the feasibility of human stem cell engraftment into an ablated mouse organ of Corti.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Differential mode of cholesterol inclusion with 2-hydroxypropyl-cyclodextrins increases safety margin in treatment of Niemann-Pick disease type C

BACKGROUND AND PURPOSE

Niemann-Pick disease type C (NPC) is a lysosomal storage disorder with disrupted intracellular cholesterol trafficking. A cyclic heptasaccharide, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD), is a cholesterol solubilizer that is being developed to treat NPC, but its ototoxicity and pulmonary toxicity remain important issues. We have characterized 2-hydroxypropyl-γ-cyclodextrin (HP-γ-CD), a cyclic octasaccharide with a larger cavity than HP-β-CD, as a candidate drug to treat NPC. However, the molecular target of HP-γ-CD with respect to NPC and its potential for clinical application are still unclear.

EXPERIMENTAL APPROACH

We investigated the mode of interaction between HP-γ-CD and cholesterol by phase-solubility analysis, proton NMR spectroscopy and molecular dynamics simulations. We then evaluated the therapeutic effects of HP-γ-CD compared with HP-β-CD using cellular and murine NPC models. Mouse auditory and pulmonary function tests were also conducted.

KEY RESULTS

HP-γ-CD solely formed a 1:1 inclusion complex with cholesterol with an affinity similar to that of HP-β-CD. In vitro, HP-γ-CD and HP-β-CD amelioration of NPC-related manifestations was almost equivalent at lower concentrations. However, at higher concentrations, the cholesterol inclusion mode of HP-β-CD shifted to the highly soluble 2:1 complex whereas that of HP-γ-CD maintained solely the 1:1 complex. The constant lower cholesterol solubilizing ability of HP-γ-CD conferred it with significantly reduced toxicity compared with HP-β-CD, but equal efficacy in treating a mouse model of NPC.

CONCLUSIONS AND IMPLICATIONS

HP-γ-CD can serve as a fine-tuned cholesterol solubilizer for the treatment of NPC with a wider safety margin than HP-β-CD in terms of ototoxicity and pulmonary toxicity.

Optimal Management of the Unilateral Recurrent Laryngeal Nerve Involvement in Patients with Thyroid Cancer

Simple Summary

Recurrent laryngeal nerve (RLN) is the second most common structure invaded by primary or metastatic thyroid cancer. However, little is known about the optimal procedure for maintaining vocal function in patients with unilateral RLN involvement in thyroid cancer. This study aimed to evaluate various parameters of vocal function to establish the optimal management of thyroid cancer patients with unilateral RLN involvement. Based on our findings, we propose that for optimal management of unilateral RLN involvement in thyroid cancer, first, sharp dissection should be performed, and if this is impossible, a simultaneous RLN reconstruction procedure should be adopted whenever possible. These findings may help improve management of RLN involvement in patients with thyroid cancer and ensure vocal function preservation.

Abstract

We aimed to determine the optimal management of recurrent laryngeal nerve (RLN) involvement in thyroid cancer. We enrolled 80 patients with unilateral RLN involvement in thyroid cancer between 2000 and 2016. Eleven patients with preoperatively functional vocal folds (VFs) underwent sharp tumor resection to preserve the RLN (shaving group). Thirty-three patients underwent RLN reconstruction with RLN resection (reconstruction group). We divided the reconstruction group into two subgroups based on preoperative VF mobility (normal-reconstruction and paralyzed-reconstruction subgroups). In the cases where RLN reconstruction was difficult, phonosurgeries including arytenoid adduction (AA), with or without thyroplasty type I, or nerve muscle pedicle implantation with AA were performed later (phonosurgery group). We evaluated and compared vocal function among the evaluated periods and different groups. Postoperative vocal function in the shaving and normal-reconstruction subgroups was favorable. There were no significant differences between the two groups. In the paralyzed-reconstruction and phonosurgery groups, postoperative vocal function was significantly improved, and vocal function in the paralyzed-reconstruction subgroup was significantly better than that in the phonosurgery group. For optimal management of unilateral RLN involvement in thyroid cancer, first, sharp dissection should be performed, and if this is impossible, a simultaneous RLN reconstruction procedure should be adopted whenever possible.