Unilateral Biportal Endoscopy for L5-S1 Extraforaminal Stenosis (Far Out Syndrome) - Technical Note with Literature Review.

Introduction: Extraforaminal stenosis in L5-S1, or far-out syndrome (FOS), is defined as L5 nerve compression by the transverse process (TP) of the L5 and the ala of the sacrum and disc bulging with/without osteophytes and/or the thickened lumbosacral and extraforaminal ligament. This study aims to describe the unilateral biportal endoscopic decompression technique of the extraforaminal stenosis at L5-S1 or far out syndrome and evaluate its clinical results with a literature review. Case Report: A 44-year-old male presented with severe right sharp shooting pain in the buttock, thigh, leg, foot, and/or toes with numbness in the foot and toes (Visual Analog Scale [VAS] 8/10) for six months with an Oswestry disability index (ODI) score of 70%. Her pain aggravated when bending forward and performing daily routine activities. He also complained of exaggeration of pain in daily regular activities. On physical examination, power in the right lower limbs was 5/5 as per the Medical Research Council (MRC) grading, and deep tendon reflexes were normal. Pre-operative X-ray and CT scan showed no instability or calcified disc osteophyte, and magnetic resonance imaging showed extraforaminal stenosis due to disc herniation at L5-S1 in Figure 1. We performed UBE-L5-S1extraforaminal discectomy surgery to resolve his symptoms. The operative time was 68 min; blood loss was 30 mL. After surgery, the patient was followed up at one week, six weeks, three months, six months, 12 months, and two years. The pain and tingling sensation in the legs improved at the 1-week follow-up, with a VAS score of 0/10 and an ODI score of 10% at the 2-year follow-up. Patient satisfaction was surveyed using Macnab's criteria at the final follow-up visit of 2 years and was found to be excellent. Post-operative imaging showed a good extraforaminal decompression at L5-S. Conclusion: Unilateral biportal endoscopy technique has brought a paradigm shift in the treatment of spinal pathologies and has served as another treatment option for the past two decades. The UBE decompression technique for extraforaminal stenosis at L5-S1 has the advantages of minimally invasive spine surgery; it is a safe and effective treatment option for treating extraforaminal stenosis at L5-S1.

Ultrasound-guided intraoral botulinum toxin injection into the lateral pterygoid muscle for chronic temporomandibular joint dislocation.

Objectives: Botulinum toxin type A (BTX), a powerful neurotoxin, can be an effective treatment choice for diverse muscular disorders and can reduce abnormal muscle activities. Abnormal movements of the mandible can be caused by involuntary and uncontrolled contractions of the lateral pterygoid muscle (LP) in various pathological situations. Previous reports have shown that BTX can reduce abnormal contractions of the LP. However, needle placement into the LP for BTX injection requires skill, experience, and sufficient anatomical knowledge. To place the needle precisely into the LP, ultrasonography (USG) can be used as an effective needle-guidance modality. USG is a non-invasive imaging modality able to create real-time images without any potential risks, including radiation exposure. Patients and. Methods: The patients who had been performed USG-guided BTX injection into the LP using an intraoral approach were included in this study with a literature review and case presentations. Using the USG, four patients received BTX injections to treat recurrent temporomandibular dislocation and oromandibular dystonia resulting from involuntary LP activity. Result: Involuntary movements of the mandible were improved successfully in all patients, and showed satisfactory results without significant complication. Conclusion: The intraoral approach could prevent potential complications during needle placement. USG-guided BTX injection is an effective, convenient, and safe method that provides real-time imaging without unnecessary pain to the patient.

Long-term neuropeptide modulation of female sexual drive via the TRP channel in Drosophila melanogaster.

Connectomics research has made it more feasible to explore how neural circuits can generate multiple outputs. Female sexual drive provides a good model for understanding reversible, long-term functional changes in motivational circuits. After emerging, female flies avoid male courtship, but they become sexually receptive over 2 d. Mating causes females to reject further mating for several days. Here, we report that pC1 neurons, which process male courtship and regulate copulation behavior, exhibit increased CREB (cAMP response element binding protein) activity during sexual maturation and decreased CREB activity after mating. This increased CREB activity requires the neuropeptide Dh44 (Diuretic hormone 44) and its receptors. A subset of the pC1 neurons secretes Dh44, which stimulates CREB activity and increases expression of the TRP channel Pyrexia (Pyx) in more pC1 neurons. This, in turn, increases pC1 excitability and sexual drive. Mating suppresses pyx expression and pC1 excitability. Dh44 is orthologous to the conserved corticotrophin-releasing hormone family, suggesting similar roles in other species.

Combining PSII photochemistry and hydraulics improves predictions of photosynthesis and water use from mild to lethal drought.

Rising temperatures and increases in drought negatively impact the efficiency and sustainability of both agricultural and forest ecosystems. Although hydraulic limitations on photosynthesis have been extensively studied, a solid understanding of the links between whole plant hydraulics and photosynthetic processes at the cellular level under changing environmental conditions is still missing, hampering our predictive power for plant mortality. Here, we examined plant hydraulic traits and CO2 assimilation rate under progressive water limitation by implementing Photosystem II (PSII) dynamics with a whole plant process model (TREES). The photosynthetic responses to plant water status were parameterized based on measurements of chlorophyll a fluorescence, gas exchange and water potential for Brassica rapa (R500) grown in a greenhouse under fully watered to lethal drought conditions. The updated model significantly improved predictions of photosynthesis, stomatal conductance and leaf water potential. TREES with PSII knowledge predicted a larger hydraulic safety margin and a decrease in percent loss of conductivity. TREES predicted a slower decrease in leaf water potential, which agreed with measurements. Our results highlight the pressing need for incorporating PSII drought photochemistry into current process models to capture cross-scale plant water dynamics from cell to whole plant level.

Philosophies and Surgical Techniques for High-Grade Spondylolisthesis Treatment with Literature Review.

Introduction: High-grade spondylolisthesis is defined as cases with more than 50% displacement and spondylolisthesis with Meyerding grade III and higher. The surgical management of high-grade spondylolisthesis is highly controversial. Many surgical methods have been reported such as posterior in situ fusion, instrumented posterior fusion with or without reduction, combined anterior and posterior procedures, spondylectomy with reduction of L4 to the sacrum (for spondyloptosis), and posterior interbody fusion with trans-sacral fixation. The literature has recently mentioned minimally invasive transforaminal lumbar interbody fusion for high-grade spondylolisthesis. This study aimed to review the recent literature that describes the surgical outcomes associated with various surgical techniques used for high-grade spondylolisthesis. Materials and Methods: Recent articles were searched on search engines such as PubMed and Google Scholar using keywords such as "high-grade spondylolisthesis," "surgical techniques," and "complications." Discussion: The surgical management of high-grade spondylolisthesis is an area of significant controversy. The literature is replete with regards to the need for reduction, decompression, levels of fusion, the nature of instrumentation, surgical approaches including open, minimally invasive, and "mini-open" procedures, and various techniques for reducing the slip and fusion strategy. The three basic options of high-grade spondylolisthesis include in-situ fusion, partial reduction and fusion, and complete reduction. Conclusion: Various techniques have been described for high-grade spondylolisthesis. Spine deformity study group classification gives guidelines about balanced and unbalanced pelvis and advises reduction and fusion in case of unbalanced pelvis for correction of biomechanical and global sagittal alignment. Each of the surgical techniques has its advantages and disadvantages. However, individual authors' experience, skill levels, and anatomic reduction with fusion techniques have yielded encouraging results.

Use of Navigable Ablation Decompression Treatment (L-DISQ) for Contained Cervical Disc Herniation - Technical Note and Literature Review.

Introduction: A new navigable percutaneous disc decompressor (L'DISQ-C, U&I Co., Uijeongbu, Korea), introduced in 2012, is designed to allow direct access to herniated disc material. The L'DISQ device can be curved by rotating a control wheel, directed into disc herniation treats, and decompresses contained herniated discs with minimal collateral thermal damage. This study reports the case of contained central disc herniation in a 34-year-old male with a 2-year follow-up successfully treated with navigable ablation decompression treatment (L-DISQ). Case Report: A 34-year-old man presented to the outpatient department with a 6-month history of neck pain and bilateral upper limb radiation. His neck pain had increased progressively. At the time of presentation, his neck pain visual analog scale score was 7/10, and his neck disability index score was 30. The magnetic resonance images showed a single fluid-containing lesion with a hyperintense zone at the C4-5 levels with central disc herniation. The patient was successfully treated with the navigable ablation decompression treatment (L-DISQ) procedure. Conclusion: The navigable ablation decompression treatment (L-DISQ) is a valuable technique in treating contained cervical disc herniation with rapid pain relief and improvements in functional outcomes without any significant injury to surrounding structures. It is safe, precise, and effective in the treatment of symptomatic cervical disc herniations. Large, randomized, and multicenter trials are needed to explore the potential of the same technique further.

Radiographic outcomes following surgical correction for lumbar degenerative kyphosis: the impact of supine pelvic tilt.

OBJECTIVE: Lumbar degenerative kyphosis (LDK), a flexible deformity, is a common form of sagittal imbalance in Asian countries. Assessing a patient's spine prior to surgery by using positional radiographs is becoming more crucial in determining surgical planning to achieve favorable clinical and radiographic outcomes, especially in patients with flexible deformities. This study aims to identify radiographic characteristics of supine pelvic tilt (sPT) and its relation to mechanical failure (MF) following LDK correction. METHODS: A single-center, single-surgeon retrospective analysis was performed in patients who underwent LDK correction with sacropelvic fixation between January 2014 and May 2019. Patients were grouped into pelvic match and mismatch groups according to the difference between postoperative pelvic tilt (PT) and sPT. Demographic, surgical, and radiographic parameters were compared. Chronological change of PT was assessed by comparing preoperative, supine, immediate postoperative, and final PT. RESULTS: Baseline demographics and sagittal alignments were similar between PT match (n = 25) and mismatch (n = 42) groups (p > 0.05). There was a significant difference in the rate of MF between PT match and mismatch groups (4% vs 31%, p = 0.021). Multivariable analysis demonstrated that after including control variables, PT mismatch was independently associated with the likelihood of MF development (OR 33.42, p = 0.04). CONCLUSIONS: sPT reflects postoperative PT changes; therefore, supine imaging may represent a tool that could be used for preoperative decision-making in patients with LDK or possibly those with flexible adult spinal deformity. PT mismatch > 10° or < 0° is a significant risk factor for MF following correction of LDK. Measurement of sPT would aid surgeons in optimal preoperative planning and in minimizing catastrophic MF following deformity correction surgery.

3D simulation of interosseous interference in sagittal split ramus osteotomy for mandibular asymmetry.

BACKGROUND: The purpose of this study was to evaluate the pattern of predicted interosseous interference and to determine the influencing factor to volume of bony interference using a computer-assisted simulation system. This retrospective study recruited 116 patients with mandibular prognathism who had undergone sagittal split ramus osteotomy (SSRO) with or without maxillary osteotomy. The patients were divided into 3 groups according to the amount of menton (Me) deviation: less than 2 mm (Group 1), 2-4 mm (Group 2), and more than 4 mm (Group 3). Changes in the distal segments following BSSRO and the volume of the interosseous interference between the proximal and distal segments were simulated after matching preoperative occlusion and postoperative expected occlusion with the cone-beam computed tomography data. Ramal inclinations and other skeletal measurements were analyzed before surgery, immediately after surgery, and at least 6 months after surgery. RESULTS: The anticipated interosseous interference was more frequently noted on the contralateral side of chin deviation (long side) than the deviated site (short side) in Groups 2 and 3. More interference volume was predicted at the long side (186 ± 343.9 mm3) rather than the short side (54.4 ± 124.4 mm3) in Group 3 (p = 0.033). The bilateral difference in the volume of the interosseous interference of the osteotomized mandible was significantly correlated with the Me deviation (r = - 0.257, p = 0.009) and bilateral ramal inclination (r = 0.361, p < 0.001). The predictor variable that affected the volume of the osseous interference at each side was the amount of Me deviation (p = 0.010). CONCLUSION: By using the 3D simulation system, the potential site of bony collision could be visualized and successfully reduced intraoperatively. Since the osseous interference can be existed on any side, unilaterally or bilaterally, 3D surgical simulation is necessary before surgery to predict the osseous interference and improve the ramal inclination.

Shared decision-making intervention regarding dialysis modality in patients with CKD stage 5.

BACKGROUND: Patients with kidney failure must make complicated decisions about the dialysis modalities used either at home or in-hospital. Different options have varying levels of impact on patients' physical and psychological conditions and their social life. The purpose of this study was to evaluate the implementation of an intervention designed to achieve shared decision making (SDM) in patients' options for dialysis. METHODS: SDM was performed after consent was written for stage 5 chronic kidney disease patients before dialysis, and 435 cases were performed in 408 patients from December 16, 2019 to June 30, 2021. Among these, 101 patients were compared by SDM measurement scale, patient satisfaction, disease recognition scale survey, and dialysis method. RESULTS: The average age of participants was 56 years, with a gender composition of 55 males (54.5%) and 46 females (45.5%). Following SDM, the final dialysis methods decided upon by patients and clinicians were peritoneal dialysis (67 patients, 66.3%), hemodialysis (22 patients, 21.8%), and kidney transplantation (1 patient, 1.0%). CONCLUSIONS: Among participating patients, SDM was effective when used to decide on dialysis treatment, and patients were satisfied with the dialysis method decision process. On the disease awareness scale, those who participated in this project had relatively high positive and low negative perceptions, so it can be concluded that SDM was relatively effective. The implementation of SDM was helpful in selecting patients' best dialysis methods, and SDM scale results were higher in the peritoneal dialysis group than in the hemodialysis group.

Transcutaneous Electrical Stimulation for the Prevention of Dry Eye Disease after Photorefractive Keratectomy: Randomized Controlled Trial.

Objective: To evaluate the efficacy and safety of transcutaneous electrical stimulation (TES) for the prevention of dry eye after photorefractive keratectomy (PRK). Design: Prospective, single-center, single-blinded, parallel group, placebo-controlled, randomized clinical trial. Participants: Between February 2020 and October 2020, patients at the Samsung Medical Center scheduled to undergo PRK to correct myopia were screened and enrolled. Methods: The participants in the TES group were instructed to use the electrical stimulation device (Nu Eyne 01, Nu Eyne Co) at the periocular region after the operation, whereas those in the control group were to use the sham device. Dry eye symptoms were evaluated preoperatively and postoperatively at weeks 1, 4, and 12 using the Ocular Surface Disease Index (OSDI) questionnaire, the 5-Item Dry Eye Questionnaire (DEQ-5), and the Standard Patient Evaluation for Eye Dryness II (SPEED II) questionnaire. Dry eye signs were assessed using tear break-up time (TBUT), total corneal fluorescein staining (tCFS), and total conjunctival staining score according to the National Eye Institute/Industry scale. The pain intensity was evaluated using a visual analog scale. Main Outcome Measures: Primary outcomes were OSDI and TBUT. Results: Twenty-four patients were enrolled and completed follow-up until the end of the study (12 patients in the TES group, 12 patients in the control group). Refractive outcomes and visual acuity were not different between the groups. No serious adverse event was reported with regard to device use. No significant difference in OSDI and SPEED II questionnaires and the DEQ-5 was observed between the groups in the 12th week after surgery. The TBUT scores 12 weeks after the surgery were 9.28 ± 6.90 seconds in the TES group and 5.98 ± 2.55 seconds in the control group with significant difference (P = 0.042). The tCFS and total conjunctival staining score were significantly lower in the TES group than in the control group at postoperative 4 weeks. Pain intensity at the first week was significantly lower in the TES group than in the control group by 65% (P = 0.011). Conclusion: The application of TES is safe and effective in improving dry eye disease after PRK. Financial Disclosures: The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Unilateral Biportal Endoscopic Approach for Symptomatic Adjacent Segment Disease: Case Report and Technical Note.

Introduction: Recently, lumbar degenerative disease has been treated using unilateral biportal endoscopic (UBE) lumbar interbody fusion. However, the use of the UBE approach for symptomatic ASD following lumbar interbody fusion surgery isn't illustrated widely in the literature. This case report and technical note describe the use of the UBE approach for symptomatic ASD. Case Report: A 72-year-old female who underwent conventional fusion surgery elsewhere twelve years ago at the L5-S1 level presented with severe back pain (VAS 8/10) and radicular pain in both legs (left > right) (left VAS 7/10, right VAS 7/10) for 1 year with an ODI score of 70%. Preoperative X-ray and MRI showed dynamic instability with spondylolisthesis at L4-5. We performed an upper-level extension using UBE FES techniques to resolve ASD. The operative time was 132 minutes, blood loss was 40 ml. After surgery, the patient was followed up at 1 week, 6 weeks, 3 months, 6 months, 12 months, and 2 years. The pain and tingling sensation in the legs got better at the 1-week follow-up itself with a VAS score of 0/10 and an ODI score of 10% at the 2-year follow-up. Patient satisfaction was surveyed using Odom's criteria at each follow-up visit (at 1 week, 6 weeks,3 months, 6 months, and 2 years) and found to be excellent. Postoperative imaging showed a good reduction and canal decompression at L4-5. Conclusion: The UBE fusion extension technique for ASD is a safe, less invasive, and effective treatment option for lumbar interbody fusion extension and posterior pedicle screw revision with less morbidity and early recovery.

The Past, Present, and Future of Unilateral Biportal Endoscopy with a Technical Note on Novel Endoscopic Visualization Pedicle Screw Insertion Technique and UBE-transforaminal Lumbar Interbody Fusion Technique with Literature Review.

Introduction: Over the past two decades, unilateral biportal endoscopy (UBE) has brought a new paradigm shift in the surgical treatment of spinal disorders with its innovative technique. This study aims to review the development of the UBE technique with a technical note on the novel endoscopic visualization pedicle screw (EVPS) insertion technique and UBE-transforaminal lumbar interbody fusion technique (UBE-TLIF). Case Report: A 66-year-old female presented with severe back pain (Visual Analog Scale [VAS] 8/10) and radicular pain in both legs (left > right) (left VAS 7/10 and right VAS 7/10) for one year with an Oswestry disability index (ODI) score of 70%. Her pain aggravated when bending forward and performing daily routine activities. She also complained of severe intermittent neurological claudication at a distance of <50 m. On physical examination, power in the lower limbs was 5/5 as per the Medical Research Council grading, and deep tendon reflexes were normal. She had a known case of diabetes mellitus and hypertension and was on treatment with oral medications. Pre-operative X-ray and magnetic resonance imaging showed dynamic instability with spondylolisthesis at L4-5. We performed UBE-TLIF with the EVPS insertion technique to resolve her symptoms. The operative time was 122 min; blood loss was 40 mL. After surgery, the patient was followed up at one week, six weeks, three months, six months, 12 months, and two years. The pain and tingling sensation in the legs improved at the 1-week follow-up, with a VAS score of 0/10 and an ODI score of 10% at the 2-year follow-up. Patient satisfaction was surveyed using Macnab's criteria at the final follow-up visit of 2 years and was found to be excellent. Post-operative imaging showed a good reduction and canal decompression at L4-5. Conclusion: The novel EVPS insertion technique and UBE-TLIF have the advantages of minimally invasive spine surgery; they are a safe and effective treatment option for treating lumbar spine pathologies.

The Last Touched Vertebra on Supine Radiographs Can Be the Optimal Lower Instrumented Vertebra in Adolescent Idiopathic Scoliosis Patients.

OBJECTIVE: To determine whether the last touched vertebra (LTV) on supine radiographs is suitable for the lower instrumented vertebra (LIV) in adolescent idiopathic scoliosis (AIS) correction surgery. METHODS: In total, 57 patients were included in the study following posterior instrumentation and fusion. The average follow-up period was 2.2 years. Patients were classified into 4 groups according to the relationship of the location of LIV, LTV, and the last substantially touched vertebra (LSTV) on upright radiographs and the LTV on supine radiographs. In group 1, the upright LTV and supine LTV were the same. Group 1 was subdivided into group 1A and group 1B according to whether the LTV and LSTV were different or the same, respectively. In group 2, the upright LTV was selected as the LIV, whereas in group 3, the supine LTV was selected as the LIV. The baseline characteristics and the preoperative and postoperative radiographic/clinical outcomes of the groups were analyzed. RESULTS: No differences were found in the preoperative clinical and radiographic baseline characteristics of the 4 groups except the LIV-central sacral vertical line distance. The immediate, 6-month, 1-year, and 2-year postoperative outcomes were not significantly different among the 4 groups. One patient (4.3%) in group 1A experienced radiographic addingon without clinical symptoms. No patients underwent revision surgery. CONCLUSION: The group in whom the LIV was selected as the LTV on supine x-rays showed similar postoperative radiographic and clinical results to other groups. The LTV on preoperative supine radiographs is acceptable as the LIV in AIS surgery to maximize motion segments.

The effect of charge-balanced transcutaneous electrical nerve stimulation on rodent facial nerve regeneration.

This study aimed to investigate the effect of charge-balanced transcutaneous electrical nerve stimulation (cb-TENS) in accelerating recovery of the facial function and nerve regeneration after facial nerve (FN) section in a rat model. The main trunk of the left FN was divided and immediately sutured just distal to the stylomastoid foramen in 66 Sprague-Dawley rats. The control group had no electrical stimulus. The other two groups received cb-TENS at 20 Hz (20 Hz group) or 40 Hz (40 Hz group). Cb-TENS was administered daily for seven days and then twice a week for three weeks thereafter. To assess the recovery of facial function, whisker movement was monitored for four weeks. Histopathological evaluation of nerve regeneration was performed using transmission electron microscopy (TEM) and confocal microscopy with immunofluorescence (IF) staining. In addition, the levels of various molecular biological markers that affect nerve regeneration were analyzed. Whisker movement in the cb-TENS groups showed faster and better recovery than the control group. The 40 Hz group showed significantly better movement at the first week after injury (p < 0.0125). In histopathological analyses using TEM, nerve axons and Schwann cells, which were destroyed immediately after the injury, recovered in all groups over time. However, the regeneration of the myelin sheath was remarkably rapid and thicker in the 20 Hz and 40 Hz groups than in the control group. Image analysis using IF staining showed that the expression levels of S100B and NF200 increased over time in all groups. Specifically, the expression of NF200 in the 20 Hz and 40 Hz groups increased markedly compared to the control group. The real-time polymerase chain reaction was performed on ten representative neurotrophic factors, and the levels of IL-1ß and IL-6 were significantly higher in the 20 and 40 Hz groups than in the control group (p < 0.015). Cb-TENS facilitated and accelerated FN recovery in the rat model, as it significantly reduced the recovery time for the whisker movement. The histopathological study and analysis of neurotrophic factors supported the role of cb-TENS in the enhanced regeneration of the FN.

The response of coarse root biomass to long-term CO2 enrichment and nitrogen application in a maturing Pinus taeda stand with a large broadleaved component.

Elevated atmospheric CO2 (eCO2 ) typically increases aboveground growth in both growth chamber and free-air carbon enrichment (FACE) studies. Here we report on the impacts of eCO2 and nitrogen amendment on coarse root biomass and net primary productivity (NPP) at the Duke FACE study, where half of the eight plots in a 30-year-old loblolly pine (Pinus taeda, L.) plantation, including competing naturally regenerated broadleaved species, were subjected to eCO2 (ambient, aCO2 plus 200 ppm) for 15-17 years, combined with annual nitrogen amendments (11.2 g N m-2 ) for 6 years. Allometric equations were developed following harvest to estimate coarse root (>2 mm diameter) biomass. Pine root biomass under eCO2 increased 32%, 1.80 kg m-2 above the 5.66 kg m-2 observed in aCO2 , largely accumulating in the top 30 cm of soil. In contrast, eCO2 increased broadleaved root biomass more than twofold (aCO2 : 0.81, eCO2 : 2.07 kg m-2 ), primarily accumulating in the 30-60 cm soil depth. Combined, pine and broadleaved root biomass increased 3.08 kg m-2 over aCO2 of 6.46 kg m-2 , a 48% increase. Elevated CO2 did not increase pine root:shoot ratio (average 0.24) but increased the ratio from 0.57 to 1.12 in broadleaved species. Averaged over the study (1997-2010), eCO2 increased pine, broadleaved and total coarse root NPP by 49%, 373% and 86% respectively. Nitrogen amendment had smaller effects on any component, singly or interacting with eCO2 . A sustained increase in root NPP under eCO2 over the study period indicates that soil nutrients were sufficient to maintain root growth response to eCO2 . These responses must be considered in computing coarse root carbon sequestration of the extensive southern pine and similar forests, and in modelling the responses of coarse root biomass of pine-broadleaved forests to CO2 concentration over a range of soil N availability.

Target-binding behavior of IDPs via pre-structured motifs.

Pre-Structured Motifs (PreSMos) are transient secondary structures observed in many intrinsically disordered proteins (IDPs) and serve as protein target-binding hot spots. The prefix "pre" highlights that PreSMos exist a priori in the target-unbound state of IDPs as the active pockets of globular proteins pre-exist before target binding. Therefore, a PreSMo is an "active site" of an IDP; it is not a spatial pocket, but rather a secondary structural motif. The classical and perhaps the most effective approach to understand the function of a protein has been to determine and investigate its structure. Ironically or by definition IDPs do not possess structure (here structure refers to tertiary structure only). Are IDPs then entirely structureless? The PreSMos provide us with an atomic-resolution answer to this question. For target binding, IDPs do not rely on the spatial pockets afforded by tertiary or higher structures. Instead, they utilize the PreSMos possessing particular conformations that highly presage the target-bound conformations. PreSMos are recognized or captured by targets via conformational selection (CS) before their conformations eventually become stabilized via structural induction into more ordered bound structures. Using PreSMos, a number of, if not all, IDPs can bind targets following a sequential pathway of CS followed by an induced fit (IF). This chapter presents several important PreSMos implicated in cancers, neurodegenerative diseases, and other diseases along with discussions on their conformational details that mediate target binding, a structural rationale for unstructured proteins.

Selection of Fusion Level for Adolescent Idiopathic Scoliosis Surgery : Selective Fusion versus Postoperative Decompensation.

Adolescent idiopathic scoliosis (AIS), which is associated with an extensive range of clinical and radiological presentations, is the one of the most challenging spinal disorders. The goals of surgery are to correct the deformity in 3 dimensions and to preserve motion segments while avoiding complications. Despite the ongoing evolution of classification systems and algorithms for the surgical treatment of AIS, there has been considerable debate regarding the selection of an appropriate fusion level in AIS. In addition, there is no consensus regarding the exact description, relationship, and risk factors of coronal decompensation following selective fusion. In this review, we summarize the current concepts of selection of the fusion level for AIS and review the available information about postoperative coronal decompensation.

Molecular characterization of ligand selectivity of the sex peptide receptors of Drosophila melanogaster and Aedes aegypti.

Drosophila melanogaster sex peptide receptor (DrmSPR) is a G protein-coupled receptor (GPCR) with 'dual ligand selectivity' towards sex peptide (SP) and myoinhibitory peptides (MIPs), which are only remotely related to one another. SPR is conserved in almost all the sequenced lophotrochozoan and ecdysozoan genomes. SPRs from non-drosophilid taxa, such as those from the mosquitoes Aedes aegypti (AeaSPR), Anopheles gambiae (AngSPR), and the sea slug Aplysia californica (ApcSPR), are highly sensitive to MIP, but not to SP. To understand how Drosophila SPRs evolved their SP sensitivity while maintaining MIP sensitivity, we examined ligand selectivity in a series of chimeric GPCRs that combine domains from the SP-sensitive DrmSPR and the SP-insensitive AeaSPR. We found replacement of Pro 238 (P238) in DrmSPR with the corresponding residue from AeaSPR (L310) reduced its SP sensitivity 2.7 fold without altering its MIP sensitivity. The P238 residue located in the third extracellular loop (ECL3) is conserved in Drosophila SPRs and in SPR from the moth Bombyx mori (BomSPR), which is considerably more sensitive to SP than AeaSPR, AngSPR, or ApcSPR. We found, however, that rather than improving AeaSPR's sensitivity to SP, replacement of L310 in AeaSPR with Pro significantly reduces its MIP sensitivity. Thus, our identification of a single amino acid residue critical for SP sensitivity, but not for MIP sensitivity is an important step in clarifying how DrmSPR evolved the ability to detect SP.

Salient Features of Monomeric Alpha-Synuclein Revealed by NMR Spectroscopy.

Elucidating the structural details of proteins is highly valuable and important for the proper understanding of protein function. In the case of intrinsically disordered proteins (IDPs), however, obtaining the structural details is quite challenging, as the traditional structural biology tools have only limited use. Nuclear magnetic resonance (NMR) is a unique experimental tool that provides ensemble conformations of IDPs at atomic resolution, and when studying IDPs, a slightly different experimental strategy needs to be employed than the one used for globular proteins. We address this point by reviewing many NMR investigations carried out on the α-synuclein protein, the aggregation of which is strongly correlated with Parkinson's disease.

A cyclic nucleotide-gated channel in the brain regulates olfactory modulation through neuropeptide F in fruit fly Drosophila melanogaster.

Olfactory sensing and its modulation are important for the insects in recognizing diverse odors from the environment and in making correct decisions to survive. Identifying new genes involved in olfactory modulation and unveiling their mechanisms may lead us to understand decision making processes in the central nervous system. Here, we report a novel olfactory function of the cyclic nucleotide-gated (CNG) channel CG42260 in modulating ab3A olfactory sensory neurons, which specifically respond to food-derived odors in fruit fly Drosophila melanogaster. We found that two independent CG42260 mutants show reduced responses in the ab3A neurons. Unlike mammalian CNGs, CG42260 is not expressed in the odorant sensory neurons but broadly in the central nervous system including neuropeptide-producing cells. By using molecular genetic tools, we identified CG42260 expression in one pair of neuropeptide F (NPF) positive L1-l cells known to modulate food odor responsiveness. Knockdown of CG42260 in the NPF neurons reduced production of NPF in Ll-1 cells, which in turn, led to reduction of neuronal responses of the ab3A neurons. Our findings show the novel biological function of CG42260 in modulating olfactory responses to food odor through NPF.