A Novel Fabrication of Heterogeneous Saponified Poly(Vinyl Alcohol)/Pullulan Blend Film for Improved Wound Healing Application.

In this study, a novel film of poly(vinyl alcohol) (PVA)/pullulan (PULL) with improved surface characteristics was prepared from poly(vinyl acetate) (PVAc)/PULL blend films with various mass ratios after the saponification treatment in a heterogeneous medium. According to proton nuclear magnetic resonance (1H-NMR), Fourier transform infrared, and X-ray diffraction results, it was established that the successful fabrication of saponified PVA/PULL (100/0, 90/10, and 80/20) films could be obtained from PVAc/PULL (100/0, 90/10, and 80/20) films, respectively, after 72 h saponification at 50 °C. The degree of saponification calculated from 1H-NMR analysis results showed that fully saponified PVA was obtained from all studied films. Improved hydrophilic characteristics of the saponified films were revealed by a water contact angle test. Moreover, the saponified films showed improved mechanical behavior, and the micrographs of saponified films showed higher surface roughness than the unsaponified films. This kind of saponified film can be widely used for biomedical applications. Moreover, the reported saponified film dressing extended the lifespan of dressing as determined by its self-healing capacity and considerably advanced in vivo wound-healing development, which was attributed to its multifunctional characteristics, meaning that saponified film dressings are promising candidates for full-thickness skin wound healing.

Airway leakage due to malpositioning of esophageal temperature probe during robot-assisted radical prostatectomy: a case report.

Measuring patients' core body temperature during surgery is essential and commonly performed with an esophageal temperature probe. The probe must be placed in the lower third of the esophagus for accurate measurement. In this case report, we describe our experience of discovering an inadvertently malpositioned esophageal temperature probe in the right inferior lobar bronchus, which led to ventilation-related problems in a patient undergoing prostate surgery.

Analysis of temperature effects on the protein accumulation of the FT-FD module using newly generated Arabidopsis transgenic plants.

Arabidopsis flowering is dependent on interactions between a component of the florigens FLOWERING LOCUS T (FT) and the basic leucine zipper (bZIP) transcription factor FD. These proteins form a complex that activates the genes required for flowering competence and integrates environmental cues, such as photoperiod and temperature. However, it remains largely unknown how FT and FD are regulated at the protein level. To address this, we created FT transgenic plants that express the N-terminal FLAG-tagged FT fusion protein under the control of its own promoter in ft mutant backgrounds. FT transgenic plants complemented the delayed flowering of the ft mutant and exhibited similar FT expression patterns to wild-type Col-0 plants in response to changes in photoperiod and temperature. Similarly, we generated FD transgenic plants in fd mutant backgrounds that express the N-terminal MYC-tagged FD fusion protein under the FD promoter, rescuing the late flowering phenotypes in the fd mutant. Using these transgenic plants, we investigated how temperature regulates the expression of FT and FD proteins. Temperature-dependent changes in FT and FD protein levels are primarily regulated at the transcript level, but protein-level temperature effects have also been observed to some extent. In addition, our examination of the expression patterns of FT and FD in different tissues revealed that similar to the spatial expression pattern of FT, FD mRNA was expressed in both the leaf and shoot apex, but FD protein was only detected in the apex, suggesting a regulatory mechanism that restricts FD protein expression in the leaf during the vegetative growth phase. These transgenic plants provided a valuable platform for investigating the role of the FT-FD module in flowering time regulation.

Modulation of warm temperature-sensitive growth using a phytochrome B dark reversion variant, phyB[G515E], in Arabidopsis and rice.

INTRODUCTION: Ambient temperature-induced hypocotyl elongation in Arabidopsis seedlings is sensed by the epidermis-localized phytochrome B (phyB) and transduced into auxin biosynthesis via a basic helix-loop-helix transcription factor, phytochrome-interacting factor 4 (PIF4). Once synthesized, auxin travels down from the cotyledons to the hypocotyl, triggering hypocotyl cell elongation. Thus, the phyB-PIF4 module involved in thermosensing and signal transduction is a potential genetic target for engineering warm temperature-insensitive plants. OBJECTIVES: This study aims to manipulate warm temperature-induced elongation of plants at the post-translational level using phyB variants with dark reversion, the expression of which is subjected to heat stress. METHODS: The thermosensitive growth response of Arabidopsis was manipulated by expressing the single amino acid substitution variant of phyB (phyB[G515E]), which exhibited a lower dark reversion rate than wild-type phyB. Other variants with slow (phyB[G564E]) or rapid (phyB[S584F]) dark reversion or light insensitivity (phyB[G767R]) were also included in this study for comparison. Warming-induced transient expression of phyB variants was achieved using heat shock-inducible promoters. Arabidopsis PHYB[G515E] and PHYB[G564E] were also constitutively expressed in rice in an attempt to manipulate the heat sensitivity of a monocotyledonous plant species. RESULTS: At an elevated temperature, Arabidopsis seedlings transiently expressing PHYB[G515E] under the control of a heat shock-inducible promoter exhibited shorter hypocotyls than those expressing PHYB and other PHYB variant genes. This warm temperature-insensitive growth was related to the lowered PIF4 and auxin responses. In addition, transgenic rice seedlings expressing Arabidopsis PHYB[G515E] and PHYB[G564E] showed warm temperature-insensitive shoot growth. CONCLUSION: Transient expression of phyB variants with altered dark reversion rates could serve as an effective optogenetic technique for manipulating PIF4-auxin-mediated thermomorphogenic responses in plants.

25 Years of thermomorphogenesis research: milestones and perspectives.

In 1998, Bill Gray and colleagues showed that warm temperatures trigger arabidopsis hypocotyl elongation in an auxin-dependent manner. This laid the foundation for a vibrant research discipline. With several active members of the 'thermomorphogenesis' community, we here reflect on 25 years of elevated ambient temperature research and look to the future.

Preparation and Characterization of Thermal-Insulating Microporous Breathable Al/LLDPE/CaCO3 Composite Films.

Breathable films were prepared based on linear low-density polyethylene (LLDPE), calcium carbonate (CaCO3), and aluminum (Al; 0, 2, 4, and 8 wt.%) using extrusion molding at a pilot scale. These films must generally be able to transmit moist vapor through pores (breathability) while maintaining a barrier to liquids; this was accomplished using properly formulated composites containing spherical CaCO3 fillers. The presence of LLDPE and CaCO3 was confirmed by X-ray diffraction characterization. Fourier-transform infrared spectroscopy results revealed the formation of Al/LLDPE/CaCO3 composite films. The melting and crystallization behaviors of the Al/LLDPE/CaCO3 composite films were investigated using differential scanning calorimetry. Thermogravimetric analysis results show that the prepared composites exhibited high thermal stability up to 350 °C. Moreover, the results demonstrate that surface morphology and breathability were both influenced by the presence of various Al contents, and their mechanical properties improved with increasing Al concentration. In addition, the results show that the thermal insulation capacity of the films increased after the addition of Al. The composite with 8 wt.% Al showed the highest thermal insulation capacity (34.6%), indicating a new approach to transform composite films into novel advanced materials for use in the fields of wooden house wrapping, electronics, and packaging.

Temperature perception by plants.

Plants constantly face fluctuating ambient temperatures and must adapt to survive under stressful conditions. Temperature affects many aspects of plant growth and development through a complex network of transcriptional responses. Although temperature sensing is a crucial primary step in initiating transcriptional responses via Ca2+ and/or reactive oxygen species signaling, an understanding of how plants perceive temperature has remained elusive. However, recent studies have yielded breakthroughs in our understanding of temperature sensors and thermosensation mechanisms. We review recent findings on potential temperature sensors and emerging thermosensation mechanisms, including biomolecular condensate formation through phase separation in plants. We also compare the temperature perception mechanisms of plants with those of other organisms to provide insights into understanding temperature sensing by plants.

Cryo-EM tomography and automatic segmentation delineate modular structures in the postsynaptic density.

Postsynaptic densities (PSDs) are large protein complexes associated with the postsynaptic membrane of excitatory synapses important for synaptic function including plasticity. Conventional electron microscopy (EM) typically depicts PSDs as compact disk-like structures of hundreds of nanometers in size. Biochemically isolated PSDs were also similar in dimension revealing a predominance of proteins with the ability to polymerize into an extensive scaffold; several EM studies noted their irregular contours with often small granular structures (<30 nm) and holes. Super-resolution light microscopy studies observed clusters of PSD elements and their activity-induced lateral movement. Furthermore, our recent EM study on PSD fractions after sonication observed PSD fragments (40-90 nm in size) separate from intact PSDs; however, such structures within PSDs remained unidentified. Here we examined isolated PSDs by cryo-EM tomography with our new approach of automatic segmentation that enables delineation of substructures and their quantitative analysis. The delineated substructures broadly varied in size, falling behind 30 nm or exceeding 100 nm and showed that a considerable portion of the substructures (>38%) in isolated PSDs was in the same size range as those fragments. Furthermore, substructures spanning the entire thickness of the PSD were found, large enough to contain both membrane-associated and cytoplasmic proteins of the PSD; interestingly, they were similar to nanodomains in frequency. The structures detected here appear to constitute the isolated PSD as modules of various compositions, and this modular nature may facilitate remodeling of the PSD for proper synaptic function and plasticity.

Discovery and Binding Mechanism of Pyrazoloisoquinoline-Based Novel ß-Arrestin Inverse Agonists of the Kappa-Opioid Receptor.

Chronic exposure to stress or unwanted stimuli has been known to activate kappa opioid receptor/dynorphin (KOR/DYN) systems, which could induce depressive states and develop into some psychiatric disorders. Here, we report the first discovery of pyrazoloisoquinoline-based novel KOR ß-arrestin inverse agonists through synthesis, structure-activity relationships, optimization, and the biological evaluations of µ/κ/δ opioid receptor activities with cAMP and ß-arrestin recruitment assays. The optimized compound 7q shows potent and selective ß-arrestin inverse agonism at KOR with an EC50 value of 9.33 nM in contrast to lower activities at DOR and no activity at MOR. Moreover, we use molecular dynamics simulations to predict the binding mode of the inverse agonist and propose a mechanism for the inverse agonism. We find that the transmembrane helix 6 position of the activated state is different for the OR subtypes, leading to significantly different interactions between the receptor and ß-arrestin.

The Effect of Epiphysiodesis on the Longitudinal Bone Growth of Hands or Feet in Children With Macrodactyly Based on Long-term Quantitative Analysis.

BACKGROUND: Treatment protocols for macrodactyly have not been elucidated due to its rarity and variety of clinical manifestations. This study aims to share our long-term clinical results of epiphysiodesis in children with macrodactyly. METHODS: A retrospective chart review was performed for 17 patients with isolated macrodactyly treated with epiphysiodesis over 20 years. Length and width of each phalanx in both the affected finger and the corresponding unaffected finger in the contralateral hand were measured. Results were presented in ratios of the affected to unaffected side for each phalanx. Measuring of length and width of phalanx was performed preoperatively and postoperatively at 6, 12, and 24 months, and the last follow-up session. Postoperative satisfaction scoring was done with visual analogue scale. RESULTS: The mean follow-up period was 7 years and 2 months. In the proximal phalanx, length ratio significantly decreased compared with preoperative state at after more than 24 months, in the middle phalanx after 6 months, in the distal phalanx after 12 months. When classified by the growth patterns, the progressive type showed significant decrease in length ratio at after 6 months, and the static type after 12 months. Patients were overall satisfied with the results. CONCLUSION: Epiphysiodesis effectively regulated longitudinal growth with different degree of control for different phalanges in the long-term follow-up.

A straightforward strategy for reducing variability in flowering time at warm ambient temperatures.

Ambient temperature is one of the major environmental factors affecting flowering. As the temperature rises, most plants, including Arabidopsis, flower more rapidly. In addition, phenotypic variability in flowering time tends to increase at warm ambient temperatures. The increased variability of flowering time at warm temperatures prevents accurate flowering time measurements, particularly when evaluating the flowering time of Arabidopsis plants under short-day conditions in order to restrict the photoperiodic effect. Here, we propose a simple method for reducing the variability of flowering time at warm temperatures. Instead of growing plants at different temperatures from germination, the strategy of first vegetative growth at cool temperatures and then shifting to warm temperatures allows plants to respond more stably and robustly to warm temperatures. Consistent with flowering time measurements, plants grown under the modified growth condition exhibited higher levels of FLOWERING LOCUS T (FT) gene expression than plants grown exclusively at warm temperatures. This approach enables more precise thermo-response studies of flowering time control in Arabidopsis.

Clinical Features, Long-Term Outcomes, and Prognostic Factors of Eales' Disease in Korean Patients.

PURPOSE: We studied Korean patients with Eales' disease to document clinical features, long-term outcomes, and explore its association with TB, given South Korea's high TB burden. METHODS: We retrospectively reviewed medical records of Eales' disease patients for clinical characteristics, long-term outcomes, and its association with TB. RESULTS: Among 106 eyes, the average age of diagnosis was 39.28 years, with 82.7% male and 58.7% having unilateral involvement. Patients who underwent vitrectomy showed greater long-term improvement in visual acuity (P = .047), while those with glaucoma filtration surgery showed less improvement (P = .008). Having glaucoma through disease progression was associated with poor visual outcomes (odds ratio=15.556, P < .02). 27 out of 39 patients (69.23%) who underwent IGRA screening tested positive for TB. CONCLUSIONS: In Korean patients with Eales' disease, we observed male predominance, unilateral presentation, older age of onset, and a link with TB. Timely diagnosis and management should be considered to maintain good vision in patients with Eales' disease.

Discovery of pyrazole-1-carboxamide derivatives as novel Gi-biased µ-opioid receptor agonists.

µ-Opioid receptor (MOR) Gi-biased agonists with no recruitment of ß-arrestin were introduced as a new analgesic strategy to overcome the conventional undesirable side effects of opioid receptor-targeted drugs, such as tolerance, addiction, respiratory depression, and constipation. For the development of novel Gi-biased MOR agonists, the design, synthesis, and structure-activity relationship (SAR) analysis of the aminopyrazole core skeleton were conducted according to the current SAR data of PZM21 (2a) and its derivatives. New derivatives were biologically evaluated for their agonistic effects on cyclic adenosine monophosphate (cAMP) levels for the Gi pathway and ß-arrestin recruitment in MOR/κ-opioid receptor/δ opioid receptor. An optimized selective Gi-biased agonist, Compound 17a, was discovered with potent cAMP inhibitory activities, with a 50% efficacy concentration value of 87.1 nM and no activity in the MOR ß-arrestin pathway and other subtypes. The in vivo pain relief efficacy of Compound 17a was confirmed in a dose-dependent manner with spinal nerve ligation and cisplatin-induced peripheral neuropathy rodent neuropathic pain models.

Utility of Ultrasonography for Diagnosis of Salivary Gland Sialolithiasis: A Meta-Analysis.

OBJECTIVES: We hypothesized that ultrasonography for salivary gland stone detection would have a diagnostic accuracy similar to that confirmed by sialendoscopy, sialography, or surgery. Therefore, we evaluated the diagnostic characteristics of ultrasonography in terms of submandibular and parotid stone detection compared to confirmatory methods. METHODS: We searched PubMed, Embase, the Web of Science, SCOPUS, and the Cochrane database to October 31, 2021. The risk of bias was evaluated using the QADAS-2 tool. RESULTS: Ten studies involving 1393 patients were included in the analysis. The diagnostic odds ratio of ultrasonography was 162.6013 (95% confidence interval [CI] [53.9883; 489.7208] and I2 value 81.0%). The area under the summary receiver operating characteristic curve was 0.963. The sensitivity, specificity, negative predictive value, and positive predictive value were 0.8992 (95% CI [0.8534; 0.9318]; I2  = 79.9%), 0.9664 (95% CI [0.9290; 0.9844], I2  = 65.6%), 0.8076 (95% CI [0.7256; 0.8694]; I2  = 80.4%), and 0.9853 (95% CI [0.9629; 0.9943]; I2  = 77.4%), respectively. However, high-level among-study heterogeneity (I2 ≥ 50%) was evident, attributable to the inclusion of different glands. On subgroup analysis, significant differences in the negative predictive values (parotid gland only [0.9392], submandibular gland only [0.6718], and parotid and submandibular glands [0.8105]) were apparent. We found no significant among-study difference in the sensitivity, specificity, positive predictive value, or diagnostic odds ratio (P > .05). CONCLUSION: Ultrasonography usefully detects submandibular and parotid gland stones. Ultrasonography of the parotid gland was associated with the highest diagnostic accuracy, but further clinical studies are needed. LEVEL OF EVIDENCE: NA Laryngoscope, 132:1785-1791, 2022.

Synthesis and structure-activity relationship studies of 1,5-isomers of triazole-pyrrolopyrimidine as selective Janus kinase 1 (JAK1) inhibitors.

JAK inhibitors have been considered as useful targets for the treatment of related diseases. However, first-generation JAK inhibitors have side effects such as anemia, thrombocytopenia, neutropenia and headaches which have been suggested to result from high JAK2 inhibition. Second-generation JAK inhibitors with more specific JAK isozyme inhibition have been studied to eliminate these adverse effects. In this study, novel 4-(1,5- or 2,5-triazole)-pyrrolopyrimidine derivatives with aromatic moieties were synthesized as JAK1 inhibitors, and an in vitro enzyme assay was used to evaluate the JAK inhibitory effects. Among these JAK1 inhibitors, the compound 23a showed an IC50 level of 72 nM, as well as being selective against other JAKs by 12 times or more: the results of molecular docking studies suggested that the high JAK1 selectivity resulted from a key interaction between the iodine atom of compound 23a and His-885 of hJAK1.

Usefulness of Cervical Vestibular-Evoked Myogenic Potentials for Diagnosing Patients With Superior Canal Dehiscence Syndrome: A Meta-Analysis.

OBJECTIVES: To compare the diagnostic accuracy of cervical vestibular-evoked myogenic potential (cVEMP) for detecting superior canal dehiscence (SCD) syndrome to that of computed tomography (CT) and surgical findings. DATABASES REVIEWED: PubMed, SCOPUS, Embase, Web of Science, and the Cochrane database. METHODS: Databases were searched up to July 2021. True positives, true negatives, false positives, and false negatives were extracted. Methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. RESULTS: Our search yielded nine studies with 721 patients. Including all cVEMP thresholds, the diagnostic odds ratio (DOR) was 32.8483 (95% confidence interval [CI]: 19.6577, 54.8900; I2 = 49.9%). The area under the summary receiver operating characteristic curve (AUC) was 0.879. Sensitivity and specificity were 0.8278 (95% CI: 0.7517, 0.8842; I2 = 76.4%) and 0.8824 (95% CI: 0.7859, 0.9387; I2 = 92.8%), respectively. However, there was a high degree of heterogeneity (I2 ≥ 70%) due to the different VEMP threshold values used among the studies. In subgroup analysis, higher cVEMP threshold values showed higher sensitivity (threshold ≤ 85: 0.9568; threshold ≤ 65: 0.7691) but lower specificity (threshold ≤ 85: 0.5879; threshold ≤ 65: 0.8913). The threshold ≤75 subgroup showed moderate sensitivity of 0.7455, high specificity of 0.9526, and the highest DOR of 38.9062. The AUC of this subgroup was 0.894. CONCLUSIONS: cVEMP is a reliable adjunctive tool for the clinical diagnosis of SCD. Taking the balance between sensitivity and specificity into consideration, a cVEMP threshold value of 75 showed good diagnostic accuracy.

Usefulness of imaging studies for diagnosing and localizing cerebrospinal fluid rhinorrhea: A systematic review and meta-analysis.

BACKGROUND: Our aim in this study was to determine the usefulness of diagnosis by imaging studies for the localization of cerebrospinal fluid (CSF) rhinorrhea. METHODS: PubMed, SCOPUS, Embase, Web of Science, and Cochrane Library databases were searched up to July 2021. True and false positive and negative data were collected along with the characteristics of each study. Methodologic quality was assessed using the QADAS-2 tool. RESULTS: Sixteen studies involving 472 patients were included. The diagnostic odds ratio (DOR) of imaging studies was 13.6195 (95% confidence interval [CI], 7.4756-24.8129; I2  = 28.1%). The area under the summary receiver-operating characteristic curve was 0.712. Sensitivity, specificity, negative predictive value, and positive predictive value were 0.8507 (0.7773-0.9029), 72.1%; 0.7827 (0.6865-0.8556), 26.8%; 0.5828 (0.4398-0.7132), 67.4%; and 0.9407 (0.8935-0.9678), 59.1%, respectively. In the subgroup analysis, there were significant differences for sensitivity (computed tomography [CT], 0.7421; computed tomography cisternography [CTC], 0.8872; magnetic resonance imaging [MRI], 0.8365; magnetic resonance cisternography [MRC], 0.8565; intrathecal gadolinium magnetic resonance cisternography [GaMRC], and 0.9307; radionuclide cisteronography [RNC], 0.7097; p = 0.0481) and for negative predictive value among imaging modalities (CT, 0.3028; CTC, 0.4848; MRI, 0.4658; MRC, 0.7465; GaMRC, 0.8611; and RNC, 0.5263; p = 0.0046). There were no significant differences among imaging modalities for specificity, positive predictive value, or DOR (p > 0.05). CONCLUSION: Imaging studies can be used in the diagnosis of CSF rhinorrhea. Gadolinium magnetic resonance cisternography showed the highest diagnostic accuracy. MRC showed fair diagnostic accuracy without intrathecal injection.

Exploring PIF4 's contribution to early flowering in plants under daily variable temperature and its tissue-specific flowering gene network.

Molecular mechanisms of how constant temperatures affect flowering time have been largely characterized in the model plant Arabidopsis thaliana; however, the effect of natural daily variable temperature outside laboratories is only partly explored. Several flowering genes have been shown to play important roles in temperature responses, including PHYTOCHROME-INTERACTING FACTOR 4 (PIF4) and FLOWERING LOCUS C (FLC), the two genes encoding for the transcription factors (TFs) that act antagonistically to regulate flowering time by activating and repressing floral integrator FLOWERING LOCUS T (FT), respectively. In this study, we have taken a multidisciplinary approach to explore the contribution of PIF4 to the early flowering observed in the daily variable temperature (VAR) and to broaden its transcriptional network using publicly available transcriptomic data. We observed early flowering in the natural accessions Col-0, C24 and their late flowering hybrid C24xCol grown under VAR, as compared with a constant temperature (CON). The loss-of-function mutation of PIF4 exhibits later flowering in VAR in both the Col-0 parent and the C24xCol hybrid, suggesting that PIF4, at least in part, contributes to acceleration of flowering in the VAR condition. To investigate the interplay between PIF4 and its flowering regulator counterparts, FLC and FT, we performed transcriptional analyses and found that VAR increased PIF4 transcription at the end of the day when temperature peaked at 32°C, when FT transcription was also elevated. On the other hand, we observed a decrease in FLC transcription in the 4-week-old plants grown in VAR, as well as in the plants with PIF4 overexpression grown in CON. These results raise a possibility that PIF4 might also regulate FT indirectly through the repression of FLC, in addition to the well-characterized direct control of PIF4 over FT. To further expand our view on the PIF4-orientated flowering gene network in response to temperature changes, we have constructed a coexpression-transcriptional regulatory network by combining publicly available transcriptomic data and gene regulatory interactions of PIF4 and its closely related flowering genes, PIF5, FLC, and ELF3. The network model reveals conserved and tissue-specific regulatory functions, which are useful for confirming as well as predicting the functions and regulatory interactions between these key flowering genes.

Shortened tethering filaments stabilize presynaptic vesicles in support of elevated release probability during LTP in rat hippocampus.

Long-term potentiation (LTP) is a cellular mechanism of learning and memory that results in a sustained increase in the probability of vesicular release of neurotransmitter. However, previous work in hippocampal area CA1 of the adult rat revealed that the total number of vesicles per synapse decreases following LTP, seemingly inconsistent with the elevated release probability. Here, electron-microscopic tomography (EMT) was used to assess whether changes in vesicle density or structure of vesicle tethering filaments at the active zone might explain the enhanced release probability following LTP. The spatial relationship of vesicles to the active zone varies with functional status. Tightly docked vesicles contact the presynaptic membrane, have partially formed SNARE complexes, and are primed for release of neurotransmitter upon the next action potential. Loosely docked vesicles are located within 8 nm of the presynaptic membrane where SNARE complexes begin to form. Nondocked vesicles comprise recycling and reserve pools. Vesicles are tethered to the active zone via filaments composed of molecules engaged in docking and release processes. The density of tightly docked vesicles was increased 2 h following LTP compared to control stimulation, whereas the densities of loosely docked or nondocked vesicles congregating within 45 nm above the active zones were unchanged. The tethering filaments on all vesicles were shorter and their attachment sites shifted closer to the active zone. These findings suggest that tethering filaments stabilize more vesicles in the primed state. Such changes would facilitate the long-lasting increase in release probability following LTP.