Discovery and Hit to Lead Optimization of Macrocyclic Peptides as Novel Tropomyosin Receptor Kinase A Antagonists.

Tropomyosin receptor kinases (Trks) are receptor tyrosine kinases activated by neurotrophic factors, called neurotrophins. Among them, TrkA interacts with the nerve growth factor (NGF), which leads to pain induction. mRNA-display screening was carried out to discover a hit compound 2, which inhibits protein-protein interactions between TrkA and NGF. Subsequent structure optimization improving phosphorylation inhibitory activity and serum stability was pursued using a unique process that took advantage of the peptide being synthesized by translation from mRNA. This gave peptide 19, which showed an analgesic effect in a rat incisional pain model. The peptides described here can serve as a new class of analgesics, and the structure optimization methods reported provide a strategy for discovering new peptide drugs.

HDR syndrome, detected in the neonatal period by newborn hearing screening.

Hypoparathyroidism, deafness, and renal dysplasia (HDR) syndrome is an autosomal dominant disorder. Because HDR syndrome is caused by haploinsufficiency in GATA3, it exhibits variation in the onset and progression of hearing loss. In previous reports, the automated auditory brainstem response (AABR) was considered insufficient to detect sensorineural hearing loss caused by HDR syndrome. We report a case of HDR syndrome whose congenital hearing loss was detected by newborn hearing screening (NHS) using AABR. In this case, HDR syndrome was suspected due to hearing loss, hypocalcemia, and her family history. Genetic testing confirmed the diagnosis of HDR syndrome at 5 months of age. Because the phenotype of hearing loss due to HDR syndrome is variable and includes progressive hearing loss, these cases may not be detected by the HNS. However, most of the previous reports were published before the NHS became common and given the frequency of hearing loss complications in HDR syndrome. We consider that there is a reasonable number of HDR syndrome cases with abnormalities on the NHS. We believe that the NHS may also be useful for early detection of hearing loss due to HDR syndrome.

Genome-wide identification of tandem repeats associated with splicing variation across 49 tissues in humans.

Tandem repeats (TRs) are one of the largest sources of polymorphism, and their length is associated with gene regulation. Although previous studies reported several tandem repeats regulating gene splicing in cis (spl-TRs), no large-scale study has been conducted. In this study, we established a genome-wide catalog of 9537 spl-TRs with a total of 58,290 significant TR-splicing associations across 49 tissues (false discovery rate 5%) by using Genotype-Tissue expression (GTex) Project data. Regression models explaining splicing variation by using spl-TRs and other flanking variants suggest that at least some of the spl-TRs directly modulate splicing. In our catalog, two spl-TRs are known loci for repeat expansion diseases, spinocerebellar ataxia 6 (SCA6) and 12 (SCA12). Splicing alterations by these spl-TRs were compatible with those observed in SCA6 and SCA12. Thus, our comprehensive spl-TR catalog may help elucidate the pathomechanism of genetic diseases.

Examination of Factors Affecting the Likelihood of Whether Individuals Would Purchase Cartilage Conduction Hearing Aids.

Cartilage conduction hearing aids (CC-HAs) are a novel type of hearing aid relying on cartilage conduction, the so-called third auditory conduction pathway. However, CC-HAs have only recently entered routine clinical use, and therefore data on their usefulness are lacking. The purpose of this study was to examine the possibility of assessing whether individual patients would show good adaptation to CC-HAs. Thirty-three subjects (41 ears in total) underwent a free trial of CC-HAs. Age, disease category, and the pure-tone threshold of air and bone conduction, unaided field sound threshold, aided field sound threshold, and functional gain (FG) at 0.25, 0.5, 1, 2, and 4 kHz were compared between patients who subsequently purchased and did not purchase the CC-HAs. Overall, 65.9% of the subjects purchased CC-HAs after the trial. In comparison to non-purchasers, those who decided to purchase CC-HAs showed better pure tone hearing thresholds at high frequencies for both air conduction (2 and 4 kHz) and bone conduction (1, 2, and 4 kHz), as well as for aided thresholds in the sound field (1, 2, and 4 kHz) when using CC-HAs. Therefore, the high-frequency hearing thresholds of subjects trialing CC-HAs might be helpful for identifying those who are likely to benefit from them.

Three-dimensional visualization of plant tissues and organs by X-ray micro-computed tomography.

Studies visualizing plant tissues and organs in three-dimension (3D) using micro-computed tomography (CT) published since approximately 2015 are reviewed. In this period, the number of publications in the field of plant sciences dealing with micro-CT has increased along with the development of high-performance lab-based micro-CT systems as well as the continuous development of cutting-edge technologies at synchrotron radiation facilities. The widespread use of commercially available lab-based micro-CT systems enabling phase-contrast imaging technique, which is suitable for the visualization of biological specimens composed of light elements, appears to have facilitated these studies. Unique features of the plant body, which are particularly utilized for the imaging of plant organs and tissues by micro-CT, are having functional air spaces and specialized cell walls, such as lignified ones. In this review, we briefly describe the basis of micro-CT technology first and then get down into details of its application in 3D visualization in plant sciences, which are categorized as follows: imaging of various organs, caryopses, seeds, other organs (reproductive organs, leaves, stems and petioles), various tissues (leaf venations, xylems, air-filled tissues, cell boundaries, cell walls), embolisms and root systems, hoping that wide users of microscopes and other imaging technologies will be interested also in micro-CT and obtain some hints for a deeper understanding of the structure of plant tissues and organs in 3D. Majority of the current morphological studies using micro-CT still appear to be at a qualitative level. Development of methodology for accurate 3D segmentation is needed for the transition of the studies from a qualitative level to a quantitative level in the future.

Iridium-Catalyzed Enantioselective Direct α-C-H Alkylation of Saturated Cyclic Amines with Alkenes.

Enantioselective direct α-C(sp3)-H alkylation of saturated cyclic amines having N-methylbenzimidazolyl as a directing group was realized by using a cationic iridium/chiral diphosphine catalyst. The alkylation of pyrrolidine derivatives with various terminal alkenes proceeded to give α-alkylated products in high yields with high enantioselectivities. Chiral α,α'-dialkylated pyrrolidine derivatives were also synthesized by using an excess of alkenes or by stepwise alkylation.

Three-dimensionally visualized rhizoid system of moss, Physcomitrium patens, by refraction-contrast X-ray micro-computed tomography.

Land plants have two types of shoot-supporting systems, root system and rhizoid system, in vascular plants and bryophytes. However, since the evolutionary origin of the systems is different, how much they exploit common systems or distinct systems to architect their structures is largely unknown. To understand the regulatory mechanism of how bryophytes architect the rhizoid system responding to environmental factors, we have developed the methodology to visualize and quantitatively analyze the rhizoid system of the moss, Physcomitrium patens, in 3D. The rhizoids having a diameter of 21.3 µm on the average were visualized by refraction-contrast X-ray micro-computed tomography using coherent X-ray optics available at synchrotron radiation facility SPring-8. Three types of shape (ring-shape, line and black circle) observed in tomographic slices of specimens embedded in paraffin were confirmed to be the rhizoids by optical and electron microscopy. Comprehensive automatic segmentation of the rhizoids, which appeared in three different form types in tomograms, was tested by a method using a Canny edge detector or machine learning. The accuracy of output images was evaluated by comparing with the manually segmented ground truth images using measures such as F1 score and Intersection over Union, revealing that the automatic segmentation using machine learning was more effective than that using the Canny edge detector. Thus, machine learning-based skeletonized 3D model revealed quite dense distribution of rhizoids. We successfully visualized the moss rhizoid system in 3D for the first time.

Hearing Outcomes of Transmastoid Plugging for Superior Canal Dehiscence Syndrome by Underwater Endoscopic Surgery: With Special Reference to Transient Bone Conduction Increase in Early Postoperative Period.

OBJECTIVE: To investigate the influence on hearing of transmastoid plugging of the superior semicircular canal accompanied with membranous superior canal transection by underwater endoscopic ear surgery (UWEES) for the superior semicircular canal dehiscence syndrome. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: Seven patients underwent plugging with membranous superior canal transection with UWEES from 2017 to 2019. INTERVENTION: Bone conduction (BC) thresholds (250, 500, 1000, 2000, 4000 Hz) were repetitively examined in early postoperative period. MAIN OUTCOME MEASURES: Subjective symptoms and pure-tone audiometry. RESULTS: Transient BC threshold increase was detected in all cases in early postoperative period and hearing levels were ameliorated in 1 to 2 months. The mean maximum BC threshold elevations (dB) during the early postoperative period (within 1 mo) and the postoperative stable hearing period (after 2 mo) were 18.6 and 2.9 at 250 Hz, 24.3 and 8.6 at 500 Hz, 26.4 and 8.6 at 1000 Hz, 28.6 and 7.1 at 2000 Hz, and 30.0 and 0.8 (except for scale-out cases) at 4000 Hz. respectively. The mean maximum BC thresholds in the early period were significantly elevated compared with those in the stable period at each frequency (p < 0.01). CONCLUSIONS: Hearing outcomes of transmastoid plugging with transection of the membranous superior canal by using UWEES were found favorable in a long-term follow-up. However, it caused transient reversible hearing loss in all cases. The BC increase in early postoperative period may not cause permanent hearing loss but improvement for the surgical technique may still be necessary.

Middle ear adenoma with facial palsy: A case report and a review of the literature.

A 52-year-old man presented to our emergency department with an acute onset of right-sided facial nerve (FN) palsy of House-Brackmann grade V. Electroneurography (ENoG) was conducted with no response at the right FN, as compared with the left FN (0%). We performed a biopsy of the right middle ear mass and histological studies showed the tumor to be neuroendocrine tumors (NET) of the middle ear. We resected the tumor with canal wall down mastoidectomy and reconstructed the posterior meatal wall with soft tissue. Three months after surgery, the FN paralysis had improved with House-Brackmann grade II. We reviewed cases of NET with FN palsy, and nine patients, including our case, have been reported. Our case is the first report of ENoG for the description of FN palsy due to NET. Although the ENoG value was 0%, it was remarkably improved by surgery. The other cases of NET patients with FN palsy also recovered FN function after surgery. These results suggest that it is recommended to perform the total resection of the tumor to improve the FN function.

Iridium-catalyzed enantioselective addition of an N-methyl C-H bond to α-trifluoromethylstyrenes via C-H activation.

The Ir-catalyzed enantioselective addition of an N-methyl C-H bond of 2-(methylamino)pyridine derivatives to α-trifluoromethylstyrenes proceeded via C-H activation to give chiral γ-branched amine derivatives having a trifluoromethyl-substituted stereocenter. It was found that a bulky and electron-withdrawing group at the 3-position of 2-(methylamino)pyridines was necessary for the present C-H addition reaction catalyzed by a cationic iridium/chiral bisphosphine complex.

Reverse digital artery flap for Pacinian hypertrophy of the fingertip: A rare case report.

Pacinian corpuscle hyperplasia is a pathological increase in the size (Pacinian hypertrophy) and/or density of mature Pacinian corpuscles. Although its aetiology and pathogenesis remain unclear, surgery is the main treatment. Here, we report a rare case of Pacinian hypertrophy at the fingertip treated with surgical excision and reconstruction using a reverse digital artery flap. A 47-year-old man presented with injuries to his right little finger, which was wedged in a door while unloading a truck. His fingertip was amputated and stump plasty was performed. However, severe pain persisted at the fingertip for 5 months after the surgery. Therefore, the painful part of his fingertip was resected, and reconstruction was performed using a reverse digital artery flap 6 months after the injury. Haematoxylin and eosin staining of the resected specimen revealed scar tissue with foreign body reaction and mild Pacinian hypertrophy. One year has passed since the injury, and the pain has completely disappeared. The patient regained complete range of motion in his little finger and was able to resume work without any limitations. Surgical excision with sufficient margin and reconstruction with a reverse digital artery flap is a reliable method to relieve pain due to Pacinian hypertrophy at the fingertip.

Visualization of Arabidopsis root system architecture in 3D by refraction-contrast X-ray micro-computed tomography.

Plant roots change their morphological traits in order to adapt themselves to different environmental conditions, resulting in the alteration of the root system architecture. To understand this mechanism, it is essential to visualize the morphology of the entire root system. To reveal effects of long-term alteration of gravity environment on root system development, we have performed an experiment in the International Space Station using Arabidopsis plants and obtained dried root systems grown in rockwool slabs. The X-ray computed tomography (CT) technique using industrial X-ray scanners has been introduced to visualize the root system architecture of crop species grown in soil in 3D non-invasively. In the case of the present study, however, the root system of Arabidopsis is composed of finer roots compared with typical crop plants and rockwool is also composed of fibers having similar dimension to that of the roots. A higher spatial resolution imaging method is required for distinguishing roots from rockwool. Therefore, in the present study, we tested refraction-contrast X-ray micro-CT using coherent X-ray optics available at the beamline of the synchrotron radiation facility SPring-8 for bio-imaging. We have found that a wide field of view but with low resolution obtained at the experimental Hutch 3 of this beamline provided an overview map of the root systems, while a narrow field of view but with high resolution obtained at the experimental Hutch 1 provided an extended architecture of the secondary roots, by a clear distinction between roots and individual rockwool fibers, resulting in the successful tracing of these roots from their basal regions.

Underwater Endoscopic Ear Surgery for Closure of Cholesteatomatous Labyrinthine Fistula With Preservation of Auditory Function.

OBJECTIVE: To analyze the outcomes of the underwater endoscopic ear surgery (UWEES) technique for closure of cholesteatomatous labyrinthine fistula (LF) with preservation of auditory function. STUDY DESIGN: Retrospective case review study. SETTING: Tertiary referral center. PATIENTS: A total of 12 patients with cholesteatomatous LF. INTERVENTION: Surgical method of closure using UWEES for cholesteatomatous LF to minimize inner ear damage. Artificial cerebrospinal fluid (CSF) was used as the perfusate, except for earlier cases when saline was employed. MAIN OUTCOME MEASURES: Comparison of bone conductance hearing level (BCHL) before and after surgery. A change of BCHL less than 10 dB was defined as successful preservation of bone conductance hearing. RESULTS: All cases of LF were treated successfully by closure using the UWEES technique. Seven cases were type I, one was type IIa, and four were type III according to the Milewski and Dornhoffer classification of LF. The average LF size was 3.1 mm (1-7 mm). Eleven patients were evaluated and their bone conductance hearing was well preserved in all of them (11/11). One patient was too young for preoperative evaluation of BCHL, but hearing preservation was verified 2 years later at the age of 6 years. Remarkably, none of the patients complained of vertigo, except for only a slight manifestation on postoperative day 1. CONCLUSION: The UWEES technique was effective for closure of cholesteatomatous LF with preservation of auditory function.

Adjustment by hematocrit level in calculation of removal rate in therapeutic apheresis.

Plasma volume (PV) variation during therapeutic apheresis (TA) (such as plasma exchange [PE] and selective PE using albumin solution as replacement solution or immunoadsorption plasmapheresis) has been considered to be unignorable. It changes the concentration of the target molecule and might impact its removal rate (RR.) This study aimed to evaluate the effects of PV variation on the calculation of the RR of fibrinogen and immunoglobulin by categorizing the hematocrit (Ht) change during TA into two patterns, that is, increased group and decreased group. In all modalities of TA, the Ht level frequently changed during apheresis sessions. In calculating RR, RR calculated with Ht adjustment was significantly higher than that calculated without adjustment in the increased group and significantly lower than it in the decreased group. Therefore, RR might have been underestimated in the increased group and overestimated in the decreased group when RR was calculated without Ht adjustment. Ht adjustment is suggested to be crucial in calculating RR in TA.

Multicenter Study of Congenital Middle Ear Anomalies. Report on 246 Ears.

OBJECTIVES/HYPOTHESIS: Congenital middle ear anomalies represent a relatively rare condition. This study aimed to describe the characteristics and the surgical outcomes for patients with middle ear anomalies. METHODS: A multicenter study was conducted of consecutive patients with congenital middle ear anomalies who underwent primary surgical treatment between January 2008 and December 2017. Demographics, surgical procedures, and audiometric data were registered into the institutional database. Hearing changes and postoperative air-bone gap (ABG) were evaluated 1 year after surgery. RESULTS: A total of 246 patients (246 ears) (median age: 14 years, range: 4-75 years old) were included in this study. Anomalies were subdivided using the Teunissen and Cremers classification: 53 ears (22%) were categorized as class I, comprising only stapes ankylosis; 35 ears (14%) as class II, having ossicular chain anomalies with stapes ankylosis; 139 ears (57%) as class III, having ossicular chain anomalies with a mobile stapes-footplate; and 19 ears (8%) as class IV, with aplasia of the oval window. Evaluation of hearing outcomes for 198 ears with more than 1 year of follow-up revealed that good postoperative ABG (≤20 dB) was achieved in 82% of class I, 68% of class II, 74% of class III, and 23% of class IV anomalies. The postoperative ABG in class IV was significantly worse than in class I (P < .001) or class III (P < .01). CONCLUSIONS: This study demonstrated that class III anomalies comprised the majority of middle ear anomalies and surgical outcomes for class IV anomalies are unfavorable. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E2323-E2328, 2021.

Reconstruction using a free vascularised medial femoral condyle corticoperiosteal flap for osteomyelitis of the juxta-articular distal radius: A case report and literature review.

Osteomyelitis of the epiphysis after a distal radius fracture is uncommon. If not adequately and promptly treated, the detrimental effects on wrist function can be devastating. However, management of septic bone defects of the epiphysis is significantly challenging. We report the case of a patient with juxta-articular distal radius osteomyelitis successfully treated with a free vascularised corticoperiosteal flap from the medial femoral condyle (MFC corticoperiosteal flap). A 46-year-old right-handed man fell on the grass from a height of 2 m during a demolition. He was diagnosed with a right distal radius and ulnar styloid process fracture. He underwent open reduction and internal fixation. However, he developed a deep infection, resulting in postoperative osteomyelitis. Therefore, thorough debridement was performed and an external fixator was applied. Antibiotics were administered according to the culture results. He underwent reconstruction for bone defect using an MFC corticoperiosteal flap 28 days after re-operation. The patient could resume work without limitations 4 months after the reconstruction. The infection subsided completely, and radiographs confirmed bone union at 5 months after the reconstruction. His wrist range of motion was 40° in dorsal flexion (uninjured side 70°), 50° in palmar flexion (75°), 80° in supination (90°), and 90° in pronation (90°). There was no donor site complication. The patient has reported no pain for 1 year since the injury. The use of the MFC corticoperiosteal flap for reconstruction of the juxta-articular distal radius osteomyelitis decreased the time required for bone union, enabled local antibiotic delivery to control infection, and helped preserve wrist function.

Successful Treatment of Full Thickness Frontal Skull Bone Defect With Dermal Fat Grafting and Artificial Bone Grafts.

Rigid reconstruction for frontal bone defects not only improves function, but also approximates more normal appearance. However, in cases involving dural scar contractures, a concave deformation remains when rigid reconstruction is performed without compensating for dead space created by swelling of the brain. This study involved 4 cases in which a 2-stage reconstruction procedure was used to first eliminate dead space by grafting dermal fat, and subsequently carry out rigid reconstruction to achieve a natural forehead configuration. This method is advantageous and considered to be effective in allowing dead space to be easily filled with minimal invasiveness for concave deformations of the dura mater with bone defects. Furthermore, the risk of artificial bone exposure is reduced by adding the dermal component of dermal fat, which is grafted to thinned frontal skin.

Long-Term Outcomes of Donor Site Morbidity After Sural Nerve Graft Harvesting.

Purpose: Although nerve autografts have been considered the standard treatment for peripheral nerve defects, limited studies have reported long-term outcomes of nerve harvesting over 15 years after surgery. This study aimed to evaluate the long-term outcomes of donor site morbidity after sural nerve graft harvesting. Methods: Thirteen patients for whom more than 15 years had passed after harvesting of the sural nerve for peripheral nerve defects were included. Mean follow-up was 29.5 years. Sensory disturbances and difficulty in performing foot movements immediately after surgery and currently were evaluated on a 10-point scale. Influences on daily living and work and current satisfaction with the autologous sural nerve graft were evaluated. Results: Sensory disturbances and difficulty in movement tended to improve; however, the differences between time points were not significant. Influences on activities of daily living and work were mild, and the satisfaction level for autologous sural nerve graft was high. Conclusions: Although donor site morbidity after sural nerve graft harvesting persisted for a long time after surgery, foot symptoms and functional impairment were mild. Type of study/level of evidence: Therapeutic V.

Evaluation of the positional relationship between femoral arteries and distal screws in the proximal femoral intramedullary nail for preventing iatrogenic vascular injury.

BACKGROUND AND AIMS: Iatrogenic vascular injury associated with distal screw in the intramedullary nail for femoral trochanteric fracture is a rare but serious complication. This study aimed to investigate the positional relationship between distal screws and superficial (SFA), deep (DFA), and perforating femoral artery (PFA) using computed tomography (CT) angiography and to identify the risk factors of vascular injury. PATIENTS AND METHODS: Thirty-eight patients (11 patients who underwent osteosynthesis with proximal femoral intramedullary nail and 27 healthy people) who underwent CT angiography were included. The distance from the great trochanter tip and insertion angle from posterior condylar axis (reference line) of the distal screws were measured, and the presence rates and distances from the femur of each artery within the insertion angle were investigated. RESULTS: The distance from the great trochanter tip to the distal screw was 142.5 ±â€¯8.8 mm. The insertion angle from the reference line was 27.3°±15° The measurement points were set at 130, 140, and 150 mm distal from the great trochanter tip, and the assumed insertion angle as 27°±15° Within this angle, the presence rates and distances were 50.8%/34.2 ±â€¯7.0 mm (130 mm), 38.5%/34.3 ±â€¯6.0 mm (140 mm), 30.8%/33.4 ±â€¯6.0 mm (150 mm) in SFA; 12.3%/14.2 ±â€¯3.3 mm (130 mm), 3.1%/13.1 ±â€¯5.9 mm (140 mm), and 0% (150 mm) in DFA; and 0% (130-150 mm) in PFA. The presence rate of DFA increased at the posteromedial area in the thigh, and the distance from the femur became closer. CONCLUSION: Within the angle that distal screws were likely to be inserted, the risk of DFA injury was the highest. Therefore, anatomical reduction of the femoral neck anteversion should be performed so that the distal screw will be inserted towards the anteromedial area in the thigh, and great attention should be paid not to over-drill the medial femoral cortex.

New Alternative Therapeutic Strategy for Gustilo Type IIIB Open Fractures, Using an Intra-Wound Continuous Negative Pressure Irrigation Treatment System.

The treatment of Gustilo type IIIB and IIIC open fractures remains a challenging problem, because the infection rate is 15-45%. Infection can lead to serious complications such as osteomyelitis or amputation. The intra-wound continuous negative pressure and irrigation treatment (IW-CONPIT) was developed for infected wounds and intractable ulcers, and is very effective in suppressing infection and accelerating wound healing. Here the IW-CONPIT was applied to severe open fractures for the purpose of preventing infection. After thorough debridement and lavage of the wound, bony stabilization is performed by external fixation. Dermal matrix is grafted onto any areas where the bone or tendon is exposed. A sponge containing two tubes is placed over the entire surface of the wound including the dermal matrix. Then it is covered with a film dressing to make the wound completely airtight. A bottle of physiologic saline solution is attached to one tube, and a continuous aspirator is attached to the other. This system maintains negative pressure on the wound surface, which is continuously irrigated. Thirty-five patients were treated with this method. A superficial infection developed in two cases but was resolved by additional debridement and continued application of IW-CONPIT. Complete wound healing was obtained with split thickness skin graft in all cases. There were no complications such as osteomyelitis, delayed bone union or amputation. IW-CONPIT was able to definitively prevent wound infection in Gustilo type ⅢB open fractures. We believe this method will become a standard treatment option for this condition.