Freezing treatment under light conditions leads to a dramatic enhancement of freezing tolerance in cold-acclimated Arabidopsis.

Overwintering plants survive subzero temperatures by cold acclimation (CA), wherein they acquire freezing tolerance through short-term exposure to low temperatures above 0°C. The freezing tolerance of CA plants increases when they are subsequently exposed to mild subzero temperatures, a phenomenon known as second-phase cold hardening (2PH). Here, we explored the molecular mechanism and physiological conditions of 2PH. The results show that, compared with supercooling, a freezing treatment during 2PH after CA enhanced the freezing tolerance of Arabidopsis. This required CA as a pretreatment, and was designated as second-phase freezing acclimation (2PFA). Light increased the effect of 2PFA to enhance freezing tolerance after CA. C-repeat binding factor and cold-regulated genes were downregulated by light during the 2PFA treatment, a different transcription profile from that during CA. The freezing tolerance of 2PFA plants was decreased by the presence of the photosynthetic electron transfer inhibitor 3-(3,4-dichlorophenyl)-1,1-dimethylurea during the 2PFA treatment. Compared with wild-type plants, phototropin1,2 and phyb mutants showed lower freezing tolerance after 2PFA treatment. These results show that exposure to freezing after CA increases freezing tolerance as a secondary process, and that freezing under light conditions further increases freezing tolerance via pathways involving photoreceptors and photosynthetic electron transfer.

Quantitative GABA magnetic resonance spectroscopy as a measure of motor learning function in the motor cortex after subarachnoid hemorrhage.

The neural mechanisms underlying gross and fine motor dysfunction after subarachnoid hemorrhage (SAH) remain unknown. The γ-aminobutyric acid (GABA) deficit hypothesis proposes that reduced neuronal GABA concentrations and the subsequent lack of GABA-mediated inhibition cause motor impairment after SAH. This study aimed to explore the correlation between GABA levels and a behavioral measure of motor performance in patients with SAH. Motor cortical GABA levels were assessed in 40 patients with SAH and 10 age-matched healthy controls using proton magnetic resonance spectroscopy. The GABA and N-acetylasparate (NAA) ratio was measured in the normal gray matter within the primary motor cortex. The relationship between GABA concentration and hand-motor performance was also evaluated. Results showed significantly lower GABA levels in patients with SAH's left motor cortex than in controls (GABA/NAA ratio: 0.282 ± 0.085 vs. 0.341 ± 0.031, respectively; p = 0.041). Reaction times (RTs), a behavioral measure of motor performance potentially dependent on GABAergic synaptic transmission, were significantly longer in patients than in controls (936.8 ± 303.8 vs. 440.2 ± 67.3 ms, respectively; p < 0.001). Moreover, motor cortical GABA levels and RTs exhibited a significant positive linear correlation among patients (r = 0.572, rs = 0.327, p = 0.0001). Therefore, a decrease in GABA levels in the primary motor cortex after SAH may lead to impaired cortical inhibition of neuronal function and indicates that GABA-mediated synaptic transmission in the motor cortex is critical for RT.

Anticonvulsant and antioxidant effects of lamotrigine on pilocarpine-induced status epilepticus in mice.

OBJECTIVES: The anticonvulsant and antioxidant effects of lamotrigine on status epilepticus (SE) are incompletely understood. We assessed these effects of lamotrigine on pilocarpine (Pilo)-induced SE in mice. METHODS: Male C57BL/J6 mice were assigned to three groups: the control group, Pilo (400 mg/kg, s.c.)-induced SE (Pilo group) and lamotrigine (20 mg/kg, i.p.) treated (Pilo/lamotrigine group). The latency to SE of Racine's stage 3 or higher, the mortality rate within 2 h of Pilo administration, and the duration of SE until sacrifice were examined. Nitric oxide (NO), malondialdehyde and glutathione of oxidative stress biomarkers were detected in the hippocampus of the sacrificed animals in the above groups. NO was also detected in the cultured rat hippocampal neurons treated with 4 µM Pilo, Pilo+100 µM lamotrigine (Pilo/lamotrigine) and Pilo/lamotrigine+ N-methyl-D-aspartic acid (NMDA) receptor antagonist (10 µM MK-801, 3 µM ifenprodil) to examine the antioxidant effects of lamotrigine via non-NMDA-related pathways. RESULTS: lamotrigine prolonged the latency to SE, the SE duration until sacrifice, and decreased the mortality rate in mice with Pilo-induced SE. Lamotrigine also decreased hippocampal concentrations of NO and malondialdehyde and increased the concentrations of glutathione in the SE model. Furthermore, there were significant differences in NO concentrations between groups of cultured rat hippocampal neurons treated with Pilo and Pilo/lamotrigine, and with Pilo/lamotrigine and Pilo/lamotrigine+MK-801. CONCLUSION: Our findings suggest that lamotrigine exerts anticonvulsant and antioxidant effects on SE, but its antioxidant activity may not be fully exerted via NMDA-related pathways.

Actin isovariant ACT7 controls root meristem development in Arabidopsis through modulating auxin and ethylene responses.

The meristem is the most functionally dynamic part in a plant. The shaping of the meristem requires constant cell division and elongation, which are influenced by hormones and the cytoskeletal component, actin. Although the roles of hormones in modulating meristem development have been extensively studied, the role of actin in this process is still elusive. Using the single and double mutants of the vegetative class actin, we demonstrate that actin isovariant ACT7 plays an important role in root meristem development. In the absence of ACT7, but not ACT8 and ACT2, depolymerization of actin was observed. Consistently, the act7 mutant showed reduced cell division, cell elongation, and meristem length. Intracellular distribution and trafficking of auxin transport proteins in the actin mutants revealed that ACT7 specifically functions in the root meristem to facilitate the trafficking of auxin efflux carriers PIN1 and PIN2, and consequently the transport of auxin. Compared with act7, the act7act8 double mutant exhibited slightly enhanced phenotypic response and altered intracellular trafficking. The altered distribution of auxin in act7 and act7act8 affects the response of the roots to ethylene, but not to cytokinin. Collectively, our results suggest that ACT7-dependent auxin-ethylene response plays a key role in controlling Arabidopsis root meristem development.

High D-Dimer Concentration Is a Significant Independent Prognostic Factor in Patients with Acute Large Vessel Occlusion Undergoing Endovascular Thrombectomy.

OBJECTIVE: To investigate prognostic factors that affect the modified Rankin Scale score at 3 months after onset of acute stroke in patients with large vessel occlusion who underwent endovascular thrombectomy. METHODS: We retrospectively examined 87 consecutive patients who underwent endovascular cerebral thrombectomy for acute anterior circulation large vessel occlusion at Oita University Hospital and Nagatomi Neurosurgery Hospital from January 2014 to December 2020. RESULTS: Age, National Institutes of Health Stroke Scale score, and D-dimer concentration on admission were significant univariate prognostic factors related to modified Rankin Scale score at 3 months after stroke onset. Multivariate logistic regression analysis showed that D-dimer concentration was the only significant independent prognostic factor. The area under the receiver operating characteristic curve for D-dimer concentration and modified Rankin Scale score at 3 months was 0.715 (95% confidence interval 0.599-0.831); sensitivity and specificity were 60.6% and 80.0%, respectively, using a 1.9 µg/mL cutoff value. CONCLUSIONS: Prognosis may be worse in patients undergoing acute endovascular cerebral thrombectomy with high D-dimer concentration on admission. Other treatment options should be considered for these patients.

Perfusion Parameter Obtained on 3-Tesla Magnetic Resonance Imaging and the Ki-67 Labeling Index Predict the Overall Survival of Glioblastoma.

BACKGROUND: Pulsed arterial spin-labeling, diffusion tensor imaging (DTI), and magnetic resonance spectroscopy (MRS) are useful for predicting glioma survival. We performed a comparative review of multiple parameters obtained using these pulse sequences on 3-Tesla magnetic resonance imaging (MRI) including the molecular status and Ki-67 labeling index in newly diagnosed supratentorial glioblastomas. METHODS: A total of 35 patients with glioblastomas underwent pulsed arterial spin-labeling, DTI, and MRS studies using 3-Tesla MRI preoperatively. The isocitrate dehydrogenase (IDH) mutation status, methylguanine-DNA methyltransferase methylation status, and Ki-67 labeling index were calculated from the tumor specimen. Cutoff values were identified by analyzing a receiver operating characteristic curve, and the multivariate survival statistical technique was performed to determine the significant and independent parameters for predicting overall survival. RESULTS: The multivariate Cox analysis showed that the maximum/mean relative cerebral blood flow (rCBF) ratio and the Ki-67 labeling index were significant and independent predictive parameters with a cutoff value of 1.589 for the maximum rCBF ratio, 1.286 for the mean rCBF ratio, and 19% for the Ki-67 labeling index and hazard ratios of 6.132 and 5.119, respectively. The Kaplan-Meier survival curves showed that patients with higher rCBF ratios and Ki-67 labeling indices had a shorter overall survival than others, with median overall survival durations of 479 (95% CI, 370-559) and 1243 (95% CI, 666-NA) days, respectively (P = 0.000167). CONCLUSIONS: Our findings indicate that the preoperative rCBF ratio and Ki-67 labeling index are useful parameters for predicting the overall survival of cerebral glioblastomas.

Sialic acid-binding immunoglobulin-like lectin-15 expression on peritumoral macrophages is a favorable prognostic factor for primary central nervous system lymphoma patients.

Sialic acid-binding immunoglobulin-like lectin-15 (Siglec-15) is a new immune checkpoint molecule and its role of primary central nervous system lymphoma (PCNSL) tumor microenvironment has been unclear. We explored the Siglec-15 and programed death-ligand 1 (PD-L1) expression in tumor tissues and analyzed the association between the expression of these molecules and overall survival in newly diagnosed PCNSL. A total of 60 patients diagnosed with diffuse large B-cell lymphoma in PCNSL were included in this study. The Siglec-15 and PD-L1 expression on tumor cells, intratumoral macrophages and peritumoral macrophages were immunohistochemically evaluated. The expression of Siglec-15 and PD-L1 was greater in macrophages than in tumor cells. Regarding peritumoral macrophages, the number of Siglec-15-positive samples (n = 24) was greater than the number of PD-L1-positive samples (n = 16). A multivariate Cox analysis showed that the Siglec-15 positivity of peritumoral macrophages and performance of high-dose methotrexate-based chemotherapy were independent predictors of overall survival (hazard ratio: 0.295 and 0.322, respectively). The Kaplan-Meier survival curves showed that patients with Siglec-15-positive peritumoral macrophages had longer overall survival than those with Siglec-15-negative peritumoral macrophages (median overall survival: 3018 days and 746 days, respectively; p = 0.0290). Our findings indicate that the expression of Siglec-15 on peritumoral macrophages induces a favorable outcome in PCNSL patients.

Aux/IAA14 Regulates microRNA-Mediated Cold Stress Response in Arabidopsis Roots.

The phytohormone auxin and microRNA-mediated regulation of gene expressions are key regulators of plant growth and development at both optimal and under low-temperature stress conditions. However, the mechanistic link between microRNA and auxin in regulating plant cold stress response remains elusive. To better understand the role of microRNA (miR) in the crosstalk between auxin and cold stress responses, we took advantage of the mutants of Arabidopsis thaliana with altered response to auxin transport and signal. Screening of the mutants for root growth recovery after cold stress at 4 °C revealed that the auxin signaling mutant, solitary root 1 (slr1; mutation in Aux/IAA14), shows a hypersensitive response to cold stress. Genome-wide expression analysis of miRs in the wild-type and slr1 mutant roots using next-generation sequencing revealed 180 known and 71 novel cold-responsive microRNAs. Cold stress also increased the abundance of 26-31 nt small RNA population in slr1 compared with wild type. Comparative analysis of microRNA expression shows significant differential expression of 13 known and 7 novel miRs in slr1 at 4 °C compared with wild type. Target gene expression analysis of the members from one potential candidate miR, miR169, revealed the possible involvement of miR169/NF-YA module in the Aux/IAA14-mediated cold stress response. Taken together, these results indicate that SLR/IAA14, a transcriptional repressor of auxin signaling, plays a crucial role in integrating miRs in auxin and cold responses.

The Potentiality for Development of Multiple Dural Arteriovenous Fistulas after Ligation of the Internal Jugular Vein: A Case Report.

A 74-year-old male presented with an intracranial hemorrhage caused by multiple dural arteriovenous fistulas (DAVFs) in the left transverse sinus and right sigmoid sinus. Four months previously, the patient underwent tongue cancer removal with lymph node dissection and ligation of the right internal jugular vein. Endovascular embolization (transvenous and transarterial embolization) resulted in the complete disappearance of the fistulas. Follow-up angiography revealed new arteriovenous shunts at the superior sagittal sinus and right transverse sinus, and we treated the patient with staged transarterial embolization. Finally, venous congestion almost completely resolved and the DAVFs disappeared without any sign of recurrence. This case speculates the concept of DAVF as an acquired lesion caused by intravenous hypertension and alerts clinicians to take precautions against ligation of the internal jugular vein during a cervical operation.

Photoelectron Holographic Atomic Arrangement Imaging of Cleaved Bimetal-intercalated Graphite Superconductor Surface.

From the C 1s and K 2p photoelectron holograms, we directly reconstructed atomic images of the cleaved surface of a bimetal-intercalated graphite superconductor, (Ca, K)C8, which differed substantially from the expected bulk crystal structure based on x-ray diffraction (XRD) measurements. Graphene atomic images were collected in the in-plane cross sections of the layers 3.3 Å and 5.7 Å above the photoelectron emitter C atom and the stacking structures were determined as AB- and AA-type, respectively. The intercalant metal atom layer was found between two AA-stacked graphenes. The K atomic image revealing 2 × 2 periodicity, occupying every second centre site of C hexagonal columns, was reconstructed, and the Ca 2p peak intensity in the photoelectron spectra of (Ca, K)C8 from the cleaved surface was less than a few hundredths of the K 2p peak intensity. These observations indicated that cleavage preferentially occurs at the KC8 layers containing no Ca atoms.

Relationship between Toll-like receptor-4 and mPGES-1 gene expression in local lesions of endometriosis patients.

PROBLEM: Toll-like receptors (TLRs) are innate immune receptors that mediate the pattern recognition of, and response toward, pathogens and host-derived danger signals. We reported that cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase (mPGES) mRNA were expressed in cases of endometriosis. The relationship between COX-2, mPGES-1, and TLR4 in endometriotic lesions has yet to be determined. METHOD OF STUDY: Endometriosis samples were obtained from 37 patients with endometrial cysts. Endometrial tissues were obtained from patients undergoing surgical procedures for benign gynecological conditions. COX-2, mPGES-1, and TLR4 mRNA expressions were examined by real-time quantitative reverse transcription PCR (qRT-PCR) and mPGES-1, and TLR4 protein localization was examined by immunohistochemistry. RESULTS: TLR4 proteins were mostly located to the glandular epithelium. The immunoreactivities of TLR4 and mPGES-1 from endometriosis lesions were significantly higher than those in eutopic endometrium in the proliferative phase. The expression levels of mPGES-1 mRNA in peritoneal endometriosis were higher than those in eutopic endometrium in the proliferative phase. The expression of TLR4 mRNA correlates with that of mPGES-1 mRNA and not with that of COX-2 in endometriotic lesions. CONCLUSION: Relationship between TLR4 and mPGES-1 mRNA in endometriotic lesions indicate that innate immunity may play an important role in the pathogenesis of endometriosis.

Short latency afferent inhibition associated with cortical compression and memory impairment in patients with chronic subdural hematoma.

OBJECTIVE: To evaluate the cortical excitability in patients with mild cortical compression. METHODS: The present study used short interval intracortical inhibition (SICI), intracortical facilitation (ICF), and short latency afferent inhibition (SAI) to evaluate motor cortex excitability in 16 chronic subdural hematoma (CSDH) patients with memory impairment and compared the data with those of 16 healthy controls. RESULTS: SAI was reduced in patients compared with controls (99±14 vs. 47±11% of the test size; p<0.0001, unpaired t-test). CSDH patients tended to have a high resting motor threshold and less pronounced SICI and ICF than controls, but these differences were not significant. Treatment of hematoma improved memory impairment and SAI in CSDH patients with wide individual variations that ranged from an increase of 74% to 17% of test size. CONCLUSION: These findings suggest that measuring SAI may provide a means of probing the integrity of cortical cholinergic networks in a compressed human brain.

Superficial temporal artery-to-middle cerebral artery anastomosis with encephalo-duro-myo-synangiosis as a modified operative procedure for moyamoya disease.

BACKGROUND: Various types of revascularization surgery have been performed for moyamoya disease. Although the efficacies of these operations are well recognized, the optimal operative procedure remains undecided. In this report, we describe our modified surgical revascularization procedure for moyamoya disease and retrospectively analyze the results of such surgeries on six sides in six adult patients. METHODS: Our operative procedure, combining direct and indirect bypasses, is a superficial temporal artery to middle cerebral artery anastomosis with encephalo-duro-myo-synangiosis. The encephalo-duro-myo-synangiosis is an indirect bypass combining the encephalo-duro- and encephalo-myo-synangioses. This operative procedure has been used routinely in adult patients since 2002. RESULTS: Perioperative complications were noted in one of the six operations. This complication was transient and no attributive lesions were detected on CT or MRI. Revascularization was seen in cerebral blood flow studies in all patients, and the clinical outcomes were excellent or good. Effective neovascularization through the grafts was observed in all patients in follow-up angiographies. CONCLUSIONS: This operative procedure provides needed revascularization and prevents ischemic deficits. This modified procedure is useful for responding to subsequent additional ischemia in the area of the anterior cerebral artery and should be considered one of the optimal procedures for treating moyamoya disease.

Possible involvement of interferon beta in post-operative vasculitis restricted to the tumour bed: a case report.

Cerebral vasculitis is a very rare complication after brain tumour surgery. We herein report a case and discuss the origins of this complication. A 52-year-old female was admitted because of motor aphasia due to a left frontal lobe brain tumour. The magnetic resonance imaging (MRI) study revealed a non-enhanced tumour. A partial resection of the tumour and the placement of an Ommaya's reservoir were performed. The pathological diagnosis was an oligoastrocytoma. The patient recovered well without any neurological deficits. Post-operative radiotherapy and the intravenous injection of interferon beta were performed. During these treatments, the patient showed a continued high fever. An MRI scan revealed multiple enhanced lesions in the residual tumour, thus raising suspicions about a post-operative infection. We therefore performed a tumour biopsy and the removal of the exogenous materials. The histopathological diagnosis was vasculitis in the residual tumour. The patient's consciousness and neurological symptoms recovered quickly with the steroid treatment. Following the radiotherapy (50 Gy total), complete remission of the tumour was rapidly obtained and no recurrence was observed. Cerebral vasculitis confined to the tumour bed is an unusual complication; however, this special condition was of critical importance for a successful tumour regression in this patient.

Neuroprotective and antiamnesic effect of donepezil, a nicotinic acetylcholine-receptor activator, on rats with concussive mild traumatic brain injury.

In this study we evaluated the effect of donepezil on the neurodegeneration and behavioral impairments induced by mild traumatic brain injury (MTBI). Donepezil is an acetylcholinesterase inhibitor that is used to treat Alzheimer's disease. Donepezil was given orally to rats subjected to MTBI. Treatment with a single oral dose of donepezil (12mg/kg) immediately after injury significantly attenuated MTBI-induced neuronal death and cognitive impairment as measured by preservation of neurons in the CA1 region of the hippocampus and a water maze test respectively. However, these neuroprotective effects were prevented by concomitant injection of mecamylamine, a nicotinic acetylcholine-receptor (nAChR) antagonist, indicating that protection is mediated by nAChR activation.

Expression of inducible microsomal prostaglandin E synthase in local lesions of endometriosis patients.

PROBLEM: Recently, an inducible microsomal human prostaglandin E synthase (mPGES) was identified. This enzyme converts the cyclooxygenase (COX) product, prostaglandin (PG) H(2), to PGE(2), an eicosanoid linked to carcinogenesis. Although elevated levels of PGE(2) have been observed in many tumor types including colorectal adenomas and cancers, its role in the pathophysiology of endometriosis is unknown. We previously reported increased expression of COX-2 messenger RNA (mRNA) in local lesions of endometriosis. To further elucidate the mechanism responsible for the elevated levels of PGE(2) in endometriosis, we examined the expression levels of mPGES. METHOD OF STUDY: Samples were obtained from 28 patients, fixed in formalin, and embedded in paraffin for immunohistochemical analysis. We examined the expression of mPGES mRNA in seven cases by reverse transcriptase-polymerase chain reaction using total RNA extracted from frozen samples. RESULTS: Immunohistochemistry revealed increased mPGES immunoreactivity in endometriosis samples compared with eutopic endometria. Microsomal PGES immunoreactivity was observed in both epithelial cells and stromal or inflammatory cells of endometriosis. Increased expression of mPGES-1 mRNA was detected in most of the endometriosis samples. CONCLUSION: Our results suggest that expression of mPGES in addition to COX-2 plays a role in increasing PGE(2) production in endometriosis.

Role of protein kinase C in neuroprotective effect of geranylgeranylacetone, a noninvasive inducing agent of heat shock protein, on delayed neuronal death caused by transient ischemia in rats.

We evaluated the neuroprotective effect of geranylgeranylacetone (GGA), an antiulcer agent and inducing agent of heat-shock protein (HSP), against the delayed death of hippocampal neurons induced by transient bilateral occlusion of the common carotid artery (CCA) and hypotension (40 mm Hg) lasting for 10 min. To test the hypothesis that orally administered GGA would induce protein kinase C (PKC), leading to the expression of HSP70 and protection against delayed neuronal death (DND), we gave GGA orally to rats in various regimens prior to bilateral occlusion of the CCA, and quantitatively assessed the extent of DND in region CA1 of the hippocampus at 7 days after transient ischemia. Pretreatment with a single oral dose of GGA of 800 mg/kg at 48 h before ischemia significantly attenuated DND (20.0 +/- 3.81 vs. 321.0 +/- 11.01 mm(3); p < 0.05). A similar degree of neuron sparing occurred when GGA was given 2, 4, or 8 days before ischemia. These neuroprotective effects of GGA were prevented by pretreatment with chelerythrine (CHE), a specific inhibitor of PKC, indicating that PKC may mediate GGA-dependent protection against ischemic DND. Oral GGA-induced expression of HSP70 elicited the expression of PKCdelta, and pretreatment with GGA enhanced the ischemia-induced expression of HSP70, both of which effects were prevented by pretreatment with CHE. These results suggest that a single oral dose of GGA induces the expression of PKCdelta and promotes the expression of HSP70 in the brain, and that GGA plays an important role in neuroprotection against DND. Pretreatment with a single oral dose of GGA provides an important tool for exploring the mechanisms of neuroprotection against DND of hippocampal neurons after transient ischemia.

Granulocyte colony-stimulating factor suppresses autologous tumor killing activity of the peripheral blood lymphocytes in the patients with ovarian carcinoma.

PROBLEM: Granulocyte colony-stimulating factor (G-CSF) is often administered to patients with chemotherapy-induced leukocytopenia. However, adequate attention has not been paid to its effects on cancer immunology. Reported by us and others, G-CSF often induces immunosuppression and down-regulation of response T helper (Th)2 directed immune reaction both in vivo and in vitro. In this study, we analyzed the effects of G-CSF on interferon (IFN)-gamma production and autologous tumor killing (ATK) activities of peripheral blood mononuclear cells (PBMCs). METHODS OF STUDY: In order to evaluate the cytokine-induced activation of peripheral T and natural killer (NK) cells, we analyzed IFN-gamma production by interleukin (IL)-2- and IL-12-stimulated PBMCs, using the ELISPOT assay. Specific killing of autologous tumor cells was evaluated by lactate dehydrogenase (LDH) release assay. RESULTS: The PBMC collected from both cancer-bearing patients and healthy subjects showed IL-2- and/or IL-12-induced IFN-gamma production. The frequency of IFN-gamma producing cells was significantly higher in the normal subjects compared with the patients with advanced ovarian carcinoma. The ATK activity was also enhanced in IL-2- and/or IL-12-stimulated PBMCs of patients with ovarian carcinoma. G-CSF almost completely abolished IFN-gamma production and ATK activity of PBMC stimulated with IL-2 and/or IL-12. CONCLUSIONS: The G-CSF appears to be a suppressor of antitumor immunity. Routine administration of G-CSF to cancer patients may not be recommended, except for febrile neutropenia.