The Effectiveness of Pattern Scanning Laser Trabeculoplasty as an Additional Treatment for the Patients of Open-Angle Glaucoma Receiving Full Ocular Hypotensive Medications.

Objectives: Our purpose was to examine the effectiveness of pattern scanning laser trabeculoplasty (PSLT) as an additional treatment for patients of open-angle glaucoma (OAG) receiving maximized ocular hypotensive medications (OHM). Methods: A total of 40 eyes of 33 patients (average age 72.7 ± 10.7 years) who had not previously undergone open glaucoma surgery or laser trabeculoplasty and were treated with maximized OHM between June 2018 and March 2022 were included. A 360-degree PSLT was conducted, and postoperative intraocular pressure (IOP) and survival curves at 1, 3, 6, 9, and 12 months were evaluated. Results: According to the Kaplan-Meier survival analysis, the average survival time was 8.1 months and the survival rate at 12 months was 0.55, with death defined as postoperative IOP reduction of less than 10% or requiring additional treatment. The average survival time was 4.9 months and the survival rate at 12 months was 0.28, with death defined as postoperative IOP reduction of less than 20% or requiring additional treatment. Nine eyes showed increased IOP (three eyes) or worsened visual field (six eyes) during the course and underwent additional open glaucoma surgery. In the 31 eyes which received no additional treatment after PSLT, the mean preoperative IOP was 18.5 ± 3.9 mmHg, which reduced to 15.3 ± 4.1 mmHg (p = 1.62 × 10-6), 15.5 ± 3.4 mmHg (p = 1.51 × 10-5), 15.7 ± 4.0 mmHg (p = 1.75 × 10-5), 14.7 ± 4.38 (p = 2.89 × 10-6), and 15.0 ± 4.0 mmHg (p = 5.74 × 10-9) at 1, 3, 6, 9, and 12 months after PSLT, respectively. The IOP reduction rate one year after PSLT was 18.7%. Of the 31 eyes, 13 (42%) achieved a 20% reduction in IOP compared to the baseline. Conclusions: Adjunctive treatment with PSLT in OAG patients receiving maximized OHM may be effective over 12 months of follow-up.

Artificial intelligence-based differential diagnosis of orbital MALT lymphoma and IgG4 related ophthalmic disease using hematoxylin-eosin images.

PURPOSE: To investigate the possibility of distinguishing between IgG4-related ophthalmic disease (IgG4-ROD) and orbital MALT lymphoma using artificial intelligence (AI) and hematoxylin-eosin (HE) images. METHODS: After identifying a total of 127 patients from whom we were able to procure tissue blocks with IgG4-ROD and orbital MALT lymphoma, we performed histological and molecular genetic analyses, such as gene rearrangement. Subsequently, pathological HE images were collected from these patients followed by the cutting out of 10 different image patches from the HE image of each patient. A total of 970 image patches from the 97 patients were used to construct nine different models of deep learning, and the 300 image patches from the remaining 30 patients were used to evaluate the diagnostic performance of the models. Area under the curve (AUC) and accuracy (ACC) were used for the performance evaluation of the deep learning models. In addition, four ophthalmologists performed the binary classification between IgG4-ROD and orbital MALT lymphoma. RESULTS: EVA, which is a vision-centric foundation model to explore the limits of visual representation, was the best deep learning model among the nine models. The results of EVA were ACC = 73.3% and AUC = 0.807. The ACC of the four ophthalmologists ranged from 40 to 60%. CONCLUSIONS: It was possible to construct an AI software based on deep learning that was able to distinguish between IgG4-ROD and orbital MALT. This AI model may be useful as an initial screening tool to direct further ancillary investigations.

Stromal area differences with epithelial-mesenchymal transition gene changes in conjunctival and orbital mucosa-associated lymphoid tissue lymphoma.

Purpose: To examine the molecular biological differences between conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma and orbital MALT lymphoma in ocular adnexa lymphoma. Methods: Observational case series. A total of 129 consecutive, randomized cases of ocular adnexa MALT lymphoma diagnosed histopathologically between 2008 and 2020.Total RNA was extracted from formalin-fixed paraffin-embedded tissue from ocular adnexa MALT lymphoma, and RNA-sequencing was performed. Orbital MALT lymphoma gene expression was compared with that of conjunctival MALT lymphoma. Gene set (GS) analysis detecting for gene set cluster was performed in RNA-sequence. Related proteins were further examined by immunohistochemical staining. In addition, artificial segmentation image used to count stromal area in HE images. Results: GS analysis showed differences in expression in 29 GS types in primary orbital MALT lymphoma (N=5,5, FDR q-value <0.25). The GS with the greatest difference in expression was the GS of epithelial-mesenchymal transition (EMT). Based on this GS change, immunohistochemical staining was added using E-cadherin as an epithelial marker and vimentin as a mesenchymal marker for EMT. There was significant staining of vimentin in orbital lymphoma (P<0.01, N=129) and of E-cadherin in conjunctival lesions (P=0.023, N=129). Vimentin staining correlated with Ann Arbor staging (1 versus >1) independent of age and sex on multivariate analysis (P=0.004). Stroma area in tumor were significant difference(P<0.01). Conclusion: GS changes including EMT and stromal area in tumor were used to demonstrate the molecular biological differences between conjunctival MALT lymphoma and orbital MALT lymphoma in ocular adnexa lymphomas.

Relationship between vitreous interleukin-6 levels and vitreous particles findings on widefield optical coherence tomography in posterior uveitis.

PURPOSE: To investigate relationship between vitreous interleukin-6 levels and vitreous particles findings on widefield optical coherence tomography in posterior uveitis. METHODS: This retrospective study examined vitreous inflammatory cells (hyperreflective particles) of posterior uveitis on widefield optical coherence tomography (WOCT). We examined the number of hyperreflective particles (possibility of vitreous inflammatory cells) observed on WOCT and the correlations with interleukin-6 (IL-6) levels. The relationship between vitreous IL-6 levels and image findings from WOCT from 37 eyes (34 patients) with posterior uveitis were analyzed. Mean patient age was 63.4±15.7 years. (Mean± standard deviation) IL-6 concentration in vitreous humor was 79.9±7380.9 pg/mL Uveitis was infectious in 9 cases and non-infectious in 28 cases with multiplex polymerase chain reaction system. We measured the number and size of vitreous cells in the posterior vitreous, defined as the space between the upper vitreous and the internal limiting membrane on WOCT at the macular, upper, and lower regions. Image analysis software was also used for cell counting. RESULTS: A strong correlation was seen between human and software counts. Pearson's correlation coefficient (PCC) was performed to compare categorial variables (on macular +0.866; upper cavity +0.713; lower cavity +0.568; total vitreous cavity +0.834; P<0.001 each). IL-6 levels correlated with both vitreous cell counts and cell counts observed on macular WOCT (human-counted group +0.339, P = 0.04; software-counted group +0.349, P = 0.03). Infectious uveitis showed higher IL-6 levels (P = 0.016) and high cell counts compared with non-infectious uveitis (P = 0.04). CONCLUSIONS: Vitreous number of hyperreflective particles (cells) findings on WOCTcorrelated well with human and software cell counts. Vitreous cells findings on WOCT also correlated with IL-6 concentrations on macular.

Machine Learning Model with Texture Analysis for Automatic Classification of Histopathological Images of Ocular Adnexal Mucosa-associated Lymphoid Tissue Lymphoma of Two Different Origins.

PURPOSE: The purpose of this study was to develop artificial intelligence algorithms that can distinguish between orbital and conjunctival mucosa-associated lymphoid tissue (MALT) lymphomas in pathological images. METHODS: Tissue blocks with residual MALT lymphoma and data from histological and flow cytometric studies and molecular genetic analyses such as gene rearrangement were procured for 129 patients treated between April 2008 and April 2020. We collected pathological hematoxylin and eosin-stained (HE) images of lymphoma from these patients and cropped 10 different image patches at a resolution of 2048 × 2048 from pathological images from each patient. A total of 990 images from 99 patients were used to create and evaluate machine-learning models. Each image patch of three different magnification rates at ×4, ×20, and ×40 underwent texture analysis to extract features, and then seven different machine-learning algorithms were applied to the results to create models. Cross-validation on a patient-by-patient basis was used to create and evaluate models, and then 300 images from the remaining 30 cases were used to evaluate the average accuracy rate. RESULTS: Ten-fold cross-validation using the support vector machine with linear kernel algorithm was identified as the best algorithm for discriminating between conjunctival mucosa-associated lymphoid tissue and orbital MALT lymphomas, with an average accuracy rate under cross-validation of 85%. There were ×20 magnification HE images that were more accurate in distinguishing orbital and conjunctival MALT lymphomas among ×4, ×20, and ×40. CONCLUSION: Artificial intelligence algorithms can successfully distinguish HE images between orbital and conjunctival MALT lymphomas.

Safety and efficacy of 27-gauge transconjunctival vitrectomy for the diagnosis of posterior uveitis or pan uveitis of unknown origin.

BACKGROUND: Diagnostic vitrectomy is an important method for evaluating uveitis, and its diagnostic utility is high regardless of whether the uveitis is infectious or non-infectious. The course of diagnostic vitreous surgery with 27-gauge pars plana vitrectomy and perioperative complications is reported. METHODS: An observational retrospective study of patients who underwent 27-gauge diagnostic vitrectomy due to atypical intraocular inflammation was conducted. The final diagnosis rate, complications due to surgery, preoperative visual acuity, and postoperative visual acuity (1 month and 6 months after surgery) were examined retrospectively. RESULTS: Diagnostic vitreous surgery was performed in 32 patients and 35 eyes (14 males and 18 females, age 14-85 years, median 67 years) during the study period. The average operation time was 52 min for 19 eyes with cataract surgery and 35 min for 16 eyes without cataract surgery. Preoperative log(minimum angle of resolution [MAR]) visual acuity was 0.84 ± 0.87, 1-month postoperative logMAR visual acuity was 0.41 ± 0.55 (p = 0.004, n = 28), and 6-month postoperative average logMAR visual acuity was 0.45 ± 0.73 (p = 0.012, n = 15). The diagnosis was made by diagnostic vitrectomy in 19 cases (54%). Postoperative complications were observed in 2 of 35 postoperative patients (5%); one involved increased intraocular pressure, and the other case involved vitreous hemorrhage of the eye, necessitating reoperation. CONCLUSION: Diagnostic 27-gauge vitrectomy could be effective for evaluating intraocular inflammation.

FOXP3 and CXCR4-positive regulatory T cells in the tumor stroma as indicators of tumor immunity in the conjunctival squamous cell carcinoma microenvironment.

Conjunctival squamous cell carcinoma (SCC) is the most common ocular surface neoplasia. The purpose of this retrospective study was to examine the role of regulatory T cell (Treg) activity in tumor immunity and investigate the tumor microenvironment as a new treatment focus in conjunctival SCC. Cancer progression gene array and immunohistochemical analyses of FOXP3 as a Treg marker, CD8 as a tumor-infiltrating lymphocyte marker, and CXCR4 expression on activated Tregs were conducted in a series of 31 conjunctival SCC cases. The objective was to investigate the immunoreactive response in tumor cells and stromal cells in the cancer microenvironment. The stroma ratio in tumor cells was investigated by monitoring α-smooth muscle actine (SMA) expression between carcinoma in situ (Tis) and advanced carcinoma (Tadv) (P<0.01). No significant change in PD-L1 expression was observed in this study (P = 0.15). Staining patterns of FOXP3, CD8, and CXCR4 were examined separately between tumor cells and stromal cells in SCC tumors. Differences in staining of FOXP3 in Tregs and CD8 in tumor-infiltrating lymphocytes in tumor stroma in the Tis group were observed compared with the Tadv group (each P<0.01). In addition, double immunostaining of CXCR4/FOXP3 was correlated with progression-free survival (P = 0.049). Double immunostaining of CXCR4/FOXP3 correlated with American Joint Committee on Cancer T-stage, independent of age or Ki67 index (P<0.01). Our results show that FOXP3 and the CXCR4/FOXP3 axis are important pathologic and prognostic factors of ocular surface neoplasia, including SCC. The tumor microenvironment of conjunctival SCC should be considered in the future development of treatment options.

Two Cases of Extremely High-IL-6 Pan-uveitis with Subretinal Exudation and Cell Migration.

PURPOSE: To describe two cases of extremely high-IL-6 pan-uveitis with subretinal exudation and cell migration. METHODS: Pre-operative and postoperative images and IL-6 values in vitreous samples of two pan-uveitis cases were analyzed. RESULTS: Case 1 was a 76-year-old man with blurry vision in his right eye. Fundus examination and optical coherence tomography showed vitreous opacification with vitreous cells and the presence of a white-yellowish retinal exudate with peripheral choroidal detachment all around. The IL-6 value was 16,600 pg/ml. Case 2 was a 63-year-old man with blurry vision in his right eye. On fundus examination, there was severe vitreous opacification in his right eye. The IL-6 value was 26,600 pg/ml. Importantly, there was good responsiveness to steroids and the TNF inhibitor. CONCLUSION: Unclassified intraocular inflammation might include a new category of disease with unilateral pan-uveitis with good response to steroid therapy and extremely high vitreous IL-6 values.

IL-33 induces orofacial neuropathic pain through Fyn-dependent phosphorylation of GluN2B in the trigeminal spinal subnucleus caudalis.

Orofacial neuropathic pain can cause considerable disruptions in patients' daily lives, especially because of a lack of effective medications as its underlying causative mechanisms are not fully understood. Here, we found neuron-specific expression of the interleukin (IL)-33 receptor in the trigeminal spinal subnucleus caudalis (Vc), distinct from the spinal dorsal horn. Reduction in head withdrawal threshold in response to von Frey filament stimulation of the whisker pad skin was inversely correlated with the upregulation of IL-33 in the Vc after infraorbital nerve injury (IONI). Neutralization of IL-33 in the Vc alleviated mechanical allodynia in the whisker pad skin after IONI; conversely, intracisternal administration of IL-33 elicited mechanical allodynia in the whisker pad skin, which was relieved by GluN2B antagonism. Moreover, IL-33 triggered the potentiation of GluN2B-containing N-methyl-D-aspartate receptor-mediated synaptic currents and phosphorylation of synaptosomal GluN2B in the Vc, whereas IONI-induced GluN2B phosphorylation was inhibited by neutralization of IL-33 in the Vc. IL-33-induced GluN2B phosphorylation was mediated by phosphorylation of Fyn kinase, and inhibition of the Fyn kinase pathway prevented the development of IL-33-induced mechanical allodynia. Our findings provide insights into a new mechanism by which IL-33 directly regulates synaptic transmission and suggest that IL-33 signaling could be a candidate target for therapeutic interventions for orofacial neuropathic pain.

Treatment of adult metachromatic leukodystrophy model mice using intrathecal administration of type 9 AAV vector encoding arylsulfatase A.

Metachromatic leukodystrophy (MLD) is a lysosomal storage disease caused by an arylsulfatase A (ARSA) deficiency and characterized by severe neurological symptoms resulting from demyelination within the central and peripheral nervous systems. We investigated the feasibility and efficacy of intrathecal administration of a type 9 adeno-associated viral vector encoding ARSA (AAV9/ARSA) for the treatment of 6-week-old MLD model mice, which are presymptomatic, and 1-year-old mice, which exhibit neurological abnormalities. Immunohistochemical analysis following AAV9/ARSA administration showed ARSA expression within the brain, with highest activities in the cerebellum and olfactory bulbs. In mice treated at 1 year, alcian blue staining and quantitative analysis revealed significant decreases in stored sulfatide. Behaviorally, mice treated at 1 year showed no improvement in their ability to traverse narrow balance beams as compared to untreated mice. By contrast, MLD mice treated at 6 weeks showed significant decreases in stored sulfatide throughout the entire brain and improved ability to traverse narrow balance beams. These findings suggest intrathecal administration of an AAV9/ARSA vector is a promising approach to treating genetic diseases of the central nervous system, including MLD, though it may be essential to begin therapy before the onset of neurological symptoms.

Expression of thrombospondin-1 in conjunctival squamous cell carcinoma is correlated to the Ki67 index and associated with progression-free survival.

PURPOSE: Conjunctival squamous cell carcinoma (SCC) is primarily treated with surgical resection. SCC has various stages, and local recurrence is common. The purpose of this study was to investigate thrombospondin-1 expression and its association with prognosis. METHODS: In this retrospective study, a gene expression array along with immunohistochemistry were performed for the evaluation of thrombospondin-1 expression, localization, as well as Ki67 labeling cell indices in carcinoma in situ (Tis) and advanced conjunctival SCC (Tadv). The presence or absence and intensity of cytoplasmic and nuclear staining in tumor cells were also divided into groups with a score of 0-3 and semi-quantitatively analyzed to investigate intracellular staining patterns. The association between thrombospondin-1 expression and tumor progression in a series of 31 conjunctival SCCs was further investigated. RESULTS: All 31 patients in the cohort (100%) were East Asian. A simple comparison between Tis and Tadv demonstrated significant differences in expressions of 45 genes, including thrombospondin-1 (p < 0.01). In this cohort, 30/31 tumors were positive (96%) for thrombospondin-1. Furthermore, thrombospondin-1 intracellular staining pattern analysis scores were 2.12 and 0.96 for nuclear and cytoplasmic staining, respectively, with a significant difference observed between Tis and Tadv (p < 0.01). Alteration of the Ki67 labeling index was significantly correlated with that of the thrombospondin-1 cytoplasmic score (p = 0.030). Furthermore, univariate Cox regression analysis showed a significant correlation between thrombospondin-1 staining and progression-free survival (p = 0.026) and final orbital exenteration (p = 0.019). CONCLUSIONS: The present results demonstrated that thrombospondin-1 is a potential molecular target in the pathology of conjunctival SCC, in addition to serving as a prognostic factor.

A New Model for Specific Visualization of Skin Graft Neoangiogenesis Using Flt1-tdsRed BAC Transgenic Mice.

BACKGROUND: Neovascularization plays a critical role in skin graft survival. Up to date, the lack of specificity to solely track the newly sprouting blood vessels has remained a limiting factor in skin graft transplantation models. Therefore, the authors developed a new model by using Flt1-tdsRed BAC transgenic mice. Flt1 is a vascular endothelial growth factor receptor expressed by sprouting endothelial cells mediating neoangiogenesis. The authors determined whether this model reliably visualizes neovascularization by quantifying tdsRed fluorescence in the graft over 14 days. METHODS: Cross-transplantation of two full-thickness 1 × 1-cm dorsal skin grafts was performed between 6- to 8-week-old male Flt1 mice and KSN/Slc nude mice (n = 5). The percentage of graft area occupied by tdsRed fluorescence in the central and lateral areas of the graft on days 3, 5, 9, and 14 was determined using confocal-laser scanning microscopy. RESULTS: Flt1+ endothelial cells migrating from the transgenic wound bed into the nude graft were first visible in the reticular dermis of the graft center on day 3 (0.5 ± 0.1; p < 0.05). Peak neovascularization was observed on day 9 in the lateral and central parts, increasing by 2- to 4-fold (4.6 ± 0.8 and 4.2 ± 0.9; p < 0.001). Notably, some limited neoangiogenesis was displayed within the Flt grafts on nude mice, particularly in the center. No neovascularization was observed from the wound margins. CONCLUSION: The ability of the Flt1-tdsRed transgenic mouse model to efficiently identify the origin of the skin-graft vasculature and visualize graft neovascularization over time suggests its potential utility for developing techniques that promote graft neovascularization.

Rapid Regression of Scleral Melting Associated with Tumor Necrosis Factor-α in a Case of Surgically Induced Necrotizing Scleritis.

PURPOSE: To report a case with rapid regression of scleral melting associated with tumor necrosis factor-α (TNF-α) in a surgically induced necrotizing scleritis (SINS) patient treated with local steroid therapy. CASE PRESENTATION: An 85-year-old male patient presented with conjunctival tumor in his right eye. Complete resection of the tumor lesion and conjunctival re-construction were performed. Local steroid drops were administered until 1 month after surgery, and a good clinical course was achieved. However, after stopping the local steroid, scleral melting to the uvea occurred on the center of the tumor-resected sclera. After diagnosing SINS, we immediately restarted his local steroid. After 2 weeks, there was a complete and rapid regression of the scleral melting. Following this episode, only local steroid therapy was continued for the treatment of SINS, with no recurrence observed after 6 months. Histopathological analysis revealed the infiltration of inflammatory cells during the acute phase, with TNF-α immune reactivity observed in the center of the melting site near the resected conjunctiva. CONCLUSION: We speculate that the observed changes were associated with the TNF-α that was present during the pathological state of SINS. Local steroid therapy may play a key role in the local immune balance in SINS.

Expression, intracellular localization, and mutation of EGFR in conjunctival squamous cell carcinoma and the association with prognosis and treatment.

PURPOSE: Conjunctival squamous cell carcinoma (SCC) is primarily treated with surgical resection. SCC has various stages, and local recurrence is common. The purpose of this study was to determine molecular localization of epidermal growth factor receptor (EGFR) and the possibility of EGFR as a biomarker for the management of conjunctival SCC. METHODS: In this retrospective study, we performed immunohistochemistry to evaluate EGFR expression and localization in tumor cells, EGFR mutation-specific expression (E746-A750del and L858R), and human papillomavirus expression in a series of 29 conjunctival SCCs. RESULTS: All 29 tumors in our cohort were EGFR positive (100%). Twenty-one of 29 tumors (72%) showed focal EGFR staining, and seven (28%) showed diffuse EGFR staining. In addition, we calculated the percentages of the two most important mutations in EGFR (exon 19 746-A750del (8/29, 27.5%), exon 21 (L858R mutant (2/29, 6.8%)) in conjunctival SCCs. We observed that the translocation of EGFR from the membrane into the cytoplasm was related to clinical prognosis, as we detected correlations between EGFR cytoplasmic staining and final orbital exenteration and between decreased EGFR membrane staining and progression-free survival. CONCLUSIONS: EGFR is important in the pathology of ocular surface squamous neoplasia including SCC and is a prognostic factor. Increased understanding of EGFR mutations may have important implications for future treatment options.

Noncontact Phased-Array Ultrasound Facilitates Acute Wound Healing in Mice.

BACKGROUND: The authors developed a noncontact low-frequency ultrasound device that delivers high-intensity mechanical force based on phased-array technology. It may aid wound healing because it is likely to be associated with lower risks of infection and heat-induced pain compared with conventional ultrasound methods. The authors hypothesized that the microdeformation it induces accelerates wound epithelialization. Its effects on key wound-healing processes (angiogenesis, collagen accumulation, and angiogenesis-related gene transcription) were also examined. METHODS: Immediately after wounding, bilateral acute wounds in C57BL/6J mice were noncontact low-frequency ultrasound- and sham-stimulated for 1 hour/day for 3 consecutive days (10 Hz/90.6 Pa). Wound closure (epithelialization) was recorded every 2 days as the percentage change in wound area relative to baseline. Wound tissue was procured on days 2, 5, 7, and 14 (five to six per time point) and subjected to histopathology with hematoxylin and eosin and Masson trichrome staining, CD31 immunohistochemistry, and quantitative polymerase-chain reaction analysis. RESULTS: Compared to sham-treated wounds, ultrasound/phased-array-treated wounds exhibited significantly accelerated epithelialization (65 ± 27 percent versus 30 ± 33 percent closure), angiogenesis (4.6 ± 1.7 percent versus 2.2 ± 1.0 percent CD31 area), and collagen deposition (44 ± 14 percent versus 28 ± 13 percent collagen density) on days 5, 2, and 5, respectively (all p < 0.05). The expression of Notch ligand delta-like 1 protein (Dll1) and Notch1, which participate in angiogenesis, was transiently enhanced by treatment on days 2 and 5, respectively. CONCLUSIONS: The authors' noncontact low-frequency ultrasound phased-array device improved the wound-healing rate. It was associated with increased early neovascularization that was followed by high levels of collagen-matrix production and epithelialization. The device may expand the mechanotherapeutic proangiogenesis field, thereby helping stimulate a revolution in infected wound care.

Two cases of unidentified acute compartment syndrome.

Acute compartment syndrome (ACS) is a surgical emergency that requires urgent fasciotomy to prevent irreversible sequelae. We report two cases of unidentified ACS, which did not result from traumatic injuries such as fractures or crush injury, iatrogenic injury or diseases such as haematological malignancies. Both patients complained of severe pain and swelling of their extremity. No bite marks, blisters or skin necrosis was noted. They also complained of marked symptoms of third cranial nerve injury, including divergent squint and diplopia. The diagnosis of ACS was made following continuous intracompartmental pressure measurement, and both patients underwent urgent fasciotomy with partial incision. Considering the season and location of the injuries, together with the rapid progression of signs and symptoms that included thrombocytopaenia, acute renal failure, rhabdomyolysis and especially that of third cranial nerve injury, we postulate that these two cases may have developed following mamushi (Gloydiusblomhoffii) bites.

miR-15b mediates oxaliplatin-induced chronic neuropathic pain through BACE1 down-regulation.

BACKGROUND AND PURPOSE: Although oxaliplatin is an effective anti-cancer platinum compound, it can cause painful chronic neuropathy, and its molecular mechanisms are poorly understood. MicroRNAs (miRNAs) are small non-coding RNAs that negatively regulate gene expression in a sequence-specific manner. Although miRNAs have been increasingly recognized as important modulators in a variety of pain conditions, their involvement in chemotherapy-induced neuropathic pain is unknown. EXPERIMENTAL APPROACH: Oxaliplatin-induced chronic neuropathic pain was induced in rats by i.p. injections of oxaliplatin (2 mg·kg-1 ) for five consecutive days. The expression levels of miR-15b and ß-site amyloid precursor protein-cleaving enzyme 1 (BACE1 also known as ß-secretase 1) were examined in the dorsal root ganglion (DRG). To examine the function of miR-15b, an adeno-associated viral vector encoding miR-15b was injected into the DRG in vivo. KEY RESULTS: Among the miRNAs examined in the DRG in the late phase of oxaliplatin-induced neuropathic pain, miR-15b was most robustly increased. Our in vitro assay results determined that BACE1 was a target of miR-15b. BACE1 and miR-15b were co-expressed in putative myelinated and unmyelinated DRG neurons. Overexpression of miR-15b in DRG neurons caused mechanical allodynia in association with reduced expression of BACE1. Consistent with these results, a BACE1 inhibitor dose-dependently induced significant mechanical allodynia. CONCLUSIONS AND IMPLICATIONS: These findings suggest that miR-15b contributes to oxaliplatin-induced chronic neuropathic pain at least in part through the down-regulation of BACE1.

microRNA and Pain.

Pain is an important protective system that alerts organisms to actual or possible tissue damage. However, a variety of pathologies can lead to chronic pain that is no longer beneficial. Lesions or diseases of the somatosensory nervous system cause intractable neuropathic pain that occasionally lasts even after the original pathology subsides. Chronic inflammatory diseases like arthritis are also associated with severe pain. Because conventional analgesics such as non-steroidal anti-inflammatory drugs and opioids have limited efficacy and/or severe adverse events associated with long-term use, chronic pain remains a major problem in clinical practice. Recently, causal roles of microRNAs in chronic pain and their therapeutic potential have been emerging. microRNA expressions are altered not only at the primary origin of pain, but also along the somatosensory pathways. Notably, microRNA expressions are differentially affected depending on the causes of chronic pain. This chapter summarizes current insights into the roles of microRNAs in pain based on the underlying pathologies.

Preparation of a cyclic polyphenylene array for a zigzag-type carbon nanotube segment.

Preparation of cyclic polyphenylene array 2, which corresponds to a complete carbon array of a zigzag-type CNT segment with (18,0)-structure, has been established by a Diels-Alder reaction of cyclic biphenylylene-acetylene derivative 1 with tetraphenylcyclopentadienone. The reaction of 2 with excess FeCl3 realized a presumed cyclodehydrogenation reaction and elimination of the alkyl chains that were introduced as a measure to counter the low solubility problem, but this resulted in the formation of a complicated mixture that included the mass region of a presumed zigzag-type CNT segment with (18,0)-structure. The rather efficient blue emission of cyclic compounds 1 and 2 was discussed utilizing fluorescence (FL) quantum efficiencies (Φ(FL)) and lifetimes (τ(FL)) in their crystalline state along with those in dichloromethane solution. Thermal analyses of these compounds revealed their characteristic phase transition behavior. The synthesis of a novel cyclic polyphenylene array by utilizing a Diels-Alder reaction of cyclic phenylene-acetylene compounds with tetraphenylcyclopentadienone should afford an attractive pathway to a novel belt-shaped CNT segment.