The mechanism of multistep progression of the transcriptional cascade in activated microglia as approached by a proteome approach.

The ocular cytokine network plays pivotal roles in terms of the initiation and progression of retinal degeneration. Several types of immunocompetent cells such as microglia participate in inflammation, and a temporal transition in the molecular events of inflammation has been hypothesized. We previously found that the Csf2 gene was induced in the early phase of retinal degeneration. CSF2 participates in the transcriptional activation of several cytokines expressed by microglia; however, whether CSF2 is essential in this context is not known. In this work, we approach this question by using anti-CSF2 neutralizing bntibody and the protein synthesis inhibitor cycloheximide (CHX). We first revealed that CSF2 positively regulated the cytokine induction cascade using a CSF2-neutralizing antibody (anti-CSF2) to treat the microglial cell line that were activated by lipopolysaccharide (LPS). LPS or Lipid A stimulation in the presence of the protein synthesis inhibitor cycloheximide (CHX) led to cytokine superinduction, but suppression of the expression of a few cytokines was also noted in MG5 cells. To examine transitions of the molecular events within LPS-activated microglia, we next performed proteome analysis of MG5 cells stimulated with LPS for 0, 4, and 9 h. The Database for Annotation, Visualization, and Integrated Discovery analysis of differentially expressed proteins showed that various mRNA-modifying molecules were induced after LPS stimulation, in addition to molecules involved in inflammation. However, the numbers of common proteins founded in the comparison between the induced proteins of 4 and 9 h were only one-third and one-half of induced proteins at 4 and 9 h, respectively, suggesting dynamic transition of the induced proteins. LPS-induced mRNA-modifying proteins were almost completely suppressed by CHX, as expected, suggesting that transient induction of transcription-editing proteins plays an important role in terms of the phenotype of inflammation that develops in microglia after LPS stimulation.

Downregulation of VEGF in the retinal pigment epithelium followed by choriocapillaris atrophy after NaIO3 treatment in mice.

Sodium iodate (NaIO3) induces retinal pigment epithelium (RPE) dysfunction, which leads to photoreceptor degeneration. Previously, we used electron microscopy to show that the administration of NaIO3 resulted in the accumulation of cell debris in the subretinal space, which was thought to be caused by failed phagocytosis in the outer segment of the photoreceptor due to RPE dysfunction. We further analyzed the pathological changes in the retina and choroid of NaIO3-injected mice, and found that the expression of OTX2, an RPE marker, disappeared from central part of the RPE 1 day after NaIO3 administration. Furthermore, fenestrated capillaries (choriocapillaris, CC) adjacent to the RPE could not be identified only 2 days after NaIO3 administration. An examination of the expression of the CC-specific protein plasmalemma vesicle-associated protein (PLVAP), in sections and flat-mount retina/choroid specimens showed destruction of the CC, and complete disappearance of the PLVAP signal 7 days after NaIO3 administration. In contrast, CD31 flat-mount immunohistochemistry of the retina indicated no difference in retinal vessels between NaIO3-treated mice and controls. Electron microscopy showed that the fenestrated capillaries in the kidney and duodenum were morphologically indistinguishable between control and NaIO3-treated mice. We examined cytokine production in the retina and RPE, and found that the Vegfa transcript level in the RPE decreased starting 1 day after NaIO3 administration. Taken together, these observations show that NaIO3 reduces the CC in the early stages of the pathology, which is accompanied by a rapid decrease in Vegfa expression in the RPE.

Roles of CSF2 as a modulator of inflammation during retinal degeneration.

Colony-stimulating factor 2 (CSF2) is a potent cytokine that stimulates myeloid cells, such as dendritic cells and macrophages. We have been analyzing the roles of microglia in retinal degeneration through the modulation of inflammation in the eye, and examined the roles of CSF2 in this process. Both subunits of the CSF2 receptor are expressed in microglia, but no evidence suggesting the involvement of CSF2 in inflammation in the degenerating eye has been reported. We found that Csf2 transcripts were induced in the early phase of in vitro mouse adult retina culture, used as degeneration models, suggesting that CSF2 induction is one of the earliest events occurring in the pathology of retinal degeneration. The administration of CSF2 into the retina after systemic NaIO3 treatment increased the number of microglia. To examine the roles of CSF2 in retinal inflammation, we overexpressed CSF2 in retinal explants. Induction of CSF2 activated microglia and Müller glia, and the layer structure of the retina was severely perturbed. CC motif chemokine ligand 2 (Ccl2) and C-X-C motif chemokine ligand 10 (Cxcl10), both of which are expressed in activated microglia, were strongly induced by the expression of CSF2 in the retina. The addition of CSF2 to primary retinal microglia and the microglial cell lines MG5 and BV2 showed statistically significant increase in Ccl2 and Il1b transcripts. Furthermore, CSF2 induced proliferation, migration, and phagocytosis in MG5 and/or BV2. The effects of CSF2 on microglia were mild, suggesting that CSF2 induced strong inflammation in the context of the retinal environment.

Neuropathic pain development and maintenance and its association with motor recovery after cervical spinal cord injury.

BACKGROUND: In our published randomized controlled trial, we revealed that patients with acute ASIA Grade C incomplete cervical spinal cord injury (SCI) who underwent early surgery (within 24 h post-injury) had accelerated motor recovery at six months than those with delayed surgery (>2 weeks post-injury); however, neuropathic pain (NeP) worsened regardless of surgery timing. Here, we conducted post-hoc analyses to intensively assess NeP development and maintenance. METHODS: Of 44 patients (median 64.5 years; three female; early intervention, n = 26), NeP was categorized into at-level and below-level pain and evaluated at  two weeks and one year after injury using the Neuropathic Pain Symptom Inventory (NPSI). We compared the two groups based on background characteristics. A mixed-design analysis of variance with sex as a covariate was conducted to analyze motor recovery and Health-related quality of life (HRQOL) in groups with severe (NPSI ≥ 10) or mild (NPSI < 10) pain. RESULTS: Upper and lower limb motor impairments were comparable between both groups regardless of pain severity. Severe at-level pain remained stable and worsened at one year than mild at-level pain; however, the upper- and lower-limb motor scores and HRQOL had comparable recovery. Background characteristics did not affect severity or time course of NeP. Patients with severe below-level pain demonstrated slower lower-limb motor recovery than those with mild below-level pain, whereas HRQOL improved regardless of pain severity. CONCLUSIONS: Both at-level and below-level NeP developed and persisted relatively early in the course of traumatic SCI with incomplete motor paralysis; their severities worsened over time or remained severe since onset.

Efficacy of treatments for pain and numbness in cancer survivors: a systematic review and meta-analysis.

BACKGROUND: Pain and numbness in cancer survivors frequently have negative impacts on quality of life (QoL). This meta-analysis aimed to identify the current treatment options for pain and numbness in cancer survivors and to evaluate their effects. METHODS: Cancer survivors were defined as patients diagnosed with cancer who had completed active cancer treatment, whose conditions were stable, and who had no evidence of recurrent or progressive disease. A systematic search through the PubMed, MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Web of Science, PsycInfo, and CINAHL databases was conducted, which targeted randomized controlled trials (RCTs) published until April 2022 that evaluated any type of treatment for pain or numbness in cancer survivors. A meta-analysis was conducted using the random-effects model to obtain the effect sizes of 7 types of treatments: opioid therapy, nonopioid pharmacotherapy, interventional therapy, acupuncture, education/cognitive behavioral therapy (CBT), physical exercise, and alternative medicine. RESULTS: A total of 36 studies involving 2,870 cancer survivors were included. Among them, 35 (n=2,813) were included in the meta-analysis for pain. The analysis suggested that physical exercise [n=761; 13 studies; standardized mean difference (SMD) -0.84; 95% confidence interval (CI): -1.14 to -0.55], acupuncture (n=409; 3 studies; SMD -0.80; 95% CI: -1.04 to -0.56), and alternative medicine (n=206; 6 studies; SMD -0.44; 95% CI: -0.71 to -0.16) could significantly reduce pain. Nonopioid pharmacotherapy and education/CBT did not demonstrate significant effects. No studies were identified that investigated the effects of opioid therapy or interventional therapy on pain. Regarding numbness, 5 studies (n=566) were included in the meta-analysis. Acupuncture (n=99; 2 studies) did not demonstrate significant effects on numbness, and the effects of nonopioid pharmacotherapy, education/CBT, and physical exercise could not be determined due to the small number of included studies. No studies were identified that investigated the effects of opioid therapy, interventional therapy, or alternative medicine on numbness. CONCLUSIONS: This meta-analysis suggested that physical exercise, acupuncture, and alternative medicine may reduce pain in cancer survivors, with a very small to moderate amount of evidence. The effect of treatments for numbness could not be determined due to the limited number of included studies. Further studies are needed, particularly on widely used pharmacotherapy.

Genetic polymorphism of pleiotrophin is associated with pain experience in Japanese adults: Case-control study.

Genetic factors play a role in individual differences in pain experience. Here, we performed a genome-wide association study (GWAS) to identify novel loci regulating pain processing. We conducted a 2-stage GWAS and the candidate single-nucleotide polymorphisms (SNPs) association study on pain experience using an exploratory cohort of patients with cancer pain. The confirmatory cohort comprised of participants from the general population with and without habitual use of analgesic medication. In the exploratory cohort, we evaluated pain intensity using a numerical rating scale, recorded daily opioid dosages, and calculated pain reduction rate. In the confirmatory cohort, pain experience was defined as habitual nonsteroidal anti-inflammatory drug usage. Using linear regression models, we identified candidate SNP in the exploratory samples, and tested the association between phenotype and experienced pain in the confirmatory samples. We found 1 novel SNP (rs11764598)-located on the gene encoding for pleiotrophin on chromosome 7-that passed the genome-wide suggestive significance at 20% false discovery rate (FDR) correction in the exploratory samples of patients with cancer pain (P = 1.31 × 10-7, FDR = 0.101). We confirmed its significant association with daily analgesic usage in the confirmatory cohort (P = .028), although the minor allele affected pain experience in an opposite manner. We identified a novel genetic variant associated with pain experience. Further studies are required to validate the role of pleiotrophin in pain processing.

Exponential correlations among neuropathic components, pain intensity, and catastrophic thoughts in patients with musculoskeletal pain disorder.

BACKGROUND: Neuropathic components and catastrophic thoughts contribute to the quality of life impairments in patients with chronic pain. This retrospective cross-sectional observational study examined the extent to which neuropathic components affect pain intensity and catastrophic thoughts using a mathematical model. METHODS: Participants with chronic pain with spinal or joint disorders were rated for pain intensity using a numerical rating scale (NRS), painDETECT questionnaire (PDQ), and pain catastrophizing scale (PCS). We plotted to scatter plots between PDQ and either NRS or PCS and drew best-fit lines for patients with leg pain only. We divided patients with both leg and back pain into two clusters: located above or below the baselines, and then we drew the best-fit lines for each cluster. We performed factor analysis on PDQ items and developed and validated a discriminant to identify patients located above the baseline in another cohort of musculoskeletal disorders. RESULTS: We analyzed 163 patients with lumbar disorders and 205 patients with joint disorders. PDQ correlated exponentially with NRS and PCS of the patients located above the baseline in both disorder groups and correlated linearly or logarithmically in patients located below the baseline. Factor analysis revealed three sets of pain characteristics for each disorder. We developed the discriminant from PDQ items to identify patients showing exponential correlations and then validated it in another cohort of 137 patients. The coefficient for "pressure-evoked pain" was the highest in the discriminant. CONCLUSIONS: Mathematical models indicate neuropathic components demonstrate linear correlations with NRS and PCS generally, but exponential correlations in a cluster of the patients with musculoskeletal pain. We developed and validated the discriminant based on pain characteristics to identify such patients; "pressure-evoked pain" was the most significant contributor.

Bronchovenous Fistula During Adult Cardiac Surgery: A Case Report.

Bronchovenous fistula (BVF) associated with adult cardiac surgery is a rarely reported life-threatening condition. We present a 75-year-old woman who developed a BVF during cardiac surgery. Dense adhesion in the pleural and pericardial cavities was noted. Restrictive pulmonary pathology required high airway pressure. Transesophageal echocardiography and hemoglobin measurement were helpful for the timely diagnosis of BVF, which was controlled by transection of the right upper pulmonary vein where a vent catheter had been inserted. Injuries around the cannulated site presumably initiated the BVF, which was worsened by high-pressure ventilation. Therefore, cannulation site might be a risk factor for BVF.

Prefectural Adequacy of Opioid Availability for Cancer Pain and Its Determinants in Japan: A Preliminary Study.

INTRODUCTION: Opioid analgesics are the mainstay of cancer pain management. The annual opioid consumption globally indicates adequate opioid availability and the quality of palliative care. We investigated the current situation regarding the adequacy of opioid availability in individual prefectures in Japan and explored the determinants of adequacy. METHODS: We analyzed nationwide databases open to public inspection depicting the current Japanese healthcare situation. Opioid consumption for cancer pain was estimated from oxycodone and morphine data in the nationwide database. On the basis of the World Health Organization recommendations, we calculated adequacy based on the annual cancer deaths in each prefecture in 2013 and 2015. We investigated the associations between adequacy and either outpatient medical expenditure for hypertension and diabetes as a proxy of primary care practice or ratios of these risk holders in community. Outpatient medical expenditures for musculoskeletal disorders and neoplasms were also investigated. RESULTS: The nationwide adequacy of opioid availability was approximately 75%. The largest gaps in adequacy between prefectures were more than 65%. The adequacy correlated with expenditure but not local volumes of hypertension and diabetes in both years. The other two expenditures did not relate to opioid availability. CONCLUSIONS: Although precise data are required, our preliminary findings indicate that primary care practice is the key regulator of adequate opioid availability. Opioid adequacy in Japan is thus delayed in matching the global standard, and gaps in opioid adequacy among prefectures should be bridged rapidly to expand universal access to effective palliative care and cancer pain relief.

Clopidogrel, an ADP-P2Y12 Receptor Antagonist, Can Prevent Severe Postoperative Pain: A Retrospective Chart Review.

The purinergic P2Y12 receptor regulates microglial activation, resulting in persistence and aggravation of pain in neuropathic and nociceptive pain models. We conducted a retrospective chart review to explore the analgesic potency of the P2Y12 receptor-specific antagonist, clopidogrel, for clinical management of postoperative pain in patients who underwent abdominal surgery. Twenty-seven patients with cardiovascular comorbidities, who underwent laparoscopic abdominal surgery and had ceased aspirin (ASP, n = 17) or clopidogrel (CLP, n = 10) for 14 days pre-operatively, were enrolled retrospectively. In both groups, the number of opioids and non-steroidal anti-inflammatory drugs (NSAIDs) consumed for managing postoperative pain was compared using the chi-square test and Mann-Whitney test. Our results showed that from postoperative day (POD) 0 to POD 3, the average numerical rating reflecting the postoperative pain was comparable between the two groups (CLP: 4.0 ± 1.4 vs. ASP: 3.7 ± 0.8, P-value = 0.56). However, at POD 7, opioid consumption in the CLP-treated group (fentanyl-equivalent dose: 0.49 ± 0.56 mg) was significantly lower than that in the ASP-treated group (1.48 ± 1.35 mg, P-value = 0.037). After reaching a stable state by repeated systemic administration, clopidogrel sustained the analgesic efficacy for a certain period. In conclusion, microglial P2Y12 receptors may mediate signal transduction of postoperative nociceptive pain and enhance clinical opioid analgesia.

Chest wall deformity found in patients with primary spontaneous pneumothorax.

BACKGROUND: the current consensus is that primary spontaneous pneumothorax frequently occurs in young male patients who are tall and thin. However, upon careful observation, many chest wall deformities have been recognized in primary spontaneous pneumothorax patients. We investigated the distinctive features of the chest wall configuration of primary spontaneous pneumothorax patients by comparing them with controls (normal and Marfan syndrome patients). METHODS: the anteroposterior and transverse diameters of the bilateral hemithoraxes of each patient at predetermined levels were measured by computed tomography. The asymmetry, which was based on the right/left anteroposterior and right/left transverse diameter ratio, and thickness based on the anteroposterior/transverse ratio, were examined. RESULTS: severe anteroposterior asymmetry and transverse asymmetry were observed in Marfan syndrome patients, and moderate anteroposterior asymmetry and transverse asymmetry were observed in primary spontaneous pneumothorax patients in comparison with normal control patients. Primary spontaneous pneumothorax and Marfan patients showed flatter thoraxes than normal control patients. CONCLUSIONS: primary spontaneous pneumothorax patients tend to have asymmetric and flat thoraxes. Subclinical thoracic wall deformity observed in the primary spontaneous pneumothorax group may partly contribute to alveolar pressure heterogeneity, and may be related to subpleural bleb formation.