Phthalimide Compounds Containing a Trifluoromethylphenyl Group and Electron-Donating Aryl Groups: Color-Tuning and Enhancement of Triboluminescence.

Trifluoromethylphenyl-substituted phthalimide derivatives favorably form triboluminescence (TL) active noncentrosymmetric crystals. Oligothienyl-, oligophenyl-, and naphthyl-substituted phthalimide derivatives were successfully developed as a series of metal free TL compounds. X-ray crystal structure analyses of bithienyl and naphthyl derivatives revealed noncentrosymmetric layer structures in the same direction. Introduction of suitable electron rich π-units such as thienyl groups enhances their photoluminescence and TL characteristics, and the colors can be also controlled in the visible region. A rigid naphthyl-substituted imide derivative exhibits extremely high TL performance.

π-Extended Pentalenes: The Revival of the Old Compound from New Standpoints.

Polycyclic conjugated systems bearing carbocyclic five-membered rings have attracted much attention due to their novel electronic properties and utility in organic electronic devices. Despite possessing a 4nπ electron periphery, dibenzopentalenes have a planar structure and are fairly stable. Thus, appropriate modifications should provide desirable electronic properties. Recently, we have discovered novel Ni-catalyzed coupling reactions that constitute a versatile new route to dibenzopentalene derivatives from readily available o-bromoethynylbenzenes. Moreover, we developed another dibenzopentalene synthesis using indenone derivatives as important intermediates. These methods are applicable to π-extended pentalene derivatives possessing various functional groups and aromatic ring systems. Among them, a dinaphthylpentalene derivative shows a high hole mobility (1.8 × 10(-3) cm(2) V(-1) s(-1) ) for an amorphous material. Furthermore, this is the first pentalene derivative that can be employed as a p-type material for organic heterojunction photovoltaic cells (PCE = 0.94%, V(OC) = 0.96 V) and as organic thin-film semiconductors.

Data mining with molecular design rules identifies new class of dyes for dye-sensitised solar cells.

A major deficit in suitable dyes is stifling progress in the dye-sensitised solar cell (DSC) industry. Materials discovery strategies have afforded numerous new dyes; yet, corresponding solution-based DSC device performance has little improved upon 11% efficiency, achieved using the N719 dye over two decades ago. Research on these dyes has nevertheless revealed relationships between the molecular structure of dyes and their associated DSC efficiency. Here, such structure-property relationships have been codified in the form of molecular dye design rules, which have been judiciously sequenced in an algorithm to enable large-scale data mining of dye structures with optimal DSC performance. This affords, for the first time, a DSC-specific dye-discovery strategy that predicts new classes of dyes from surveying a representative set of chemical space. A lead material from these predictions is experimentally validated, showing DSC efficiency that is comparable to many well-known organic dyes. This demonstrates the power of this approach.

Anterior transpetrosal approach and the tumor removal rate, postoperative neurological changes, and complications: experience in 274 cases over 33 years.

OBJECTIVE: The authors report on the anterior transpetrosal approach (ATPA) and the results of surgeries performed over a 33-year period for petroclival tumors, including meningioma, trigeminal schwannoma, chordoma, and epidermoid tumor. They analyze early postoperative neurological changes, surgical complications, and trends over the decades. METHODS: A retrospective analysis of 274 surgical cases that had undergone the ATPA from January 1984 to March 2017 was conducted. Data were collected from charts, clinical summaries, operative records, and operative videos. The analyzed parameters included patient diagnosis, tumor size, disease location, operation date, tumor removal rate, pre- and postoperative neurological symptoms (consciousness level, motor and sensory deficits of the limbs, sensory aphasia, and cranial nerve III-VIII injuries), surgical deaths, and radiologically recognized brain injuries after the operation (contusion, infarction, hemorrhage). RESULTS: Gross-total resection (GTR) was achieved in 53.5% of the 243 tumors with available data. The GTR rate for meningiomas (148 cases) was 54.1%. Trigeminal schwannomas had a high GTR rate of 87.1%, whereas chordomas had a low GTR rate of 14.3%. The rate of early neurological deterioration immediately after the ATPA, referred to as "early neurological change," was as follows: consciousness disturbance in 1.9% of cases (5 cases), improvement of hemiparesis in 45.0% of cases but deterioration in 8.1% of cases, sensory aphasia in 2.3% of cases due to temporal lobe injury, improvement of cerebellar symptoms in 39.3% of cases with rare deterioration (1.9% of cases), worsening of preoperative diplopia in 49.4% of patients and rarely improving, improvement of trigeminal symptoms in 19.1% of cases (mostly trigeminal neuralgia) among the 43.7% of patients who had them preoperatively, and deterioration of facial hypesthesia and/or paresthesia in 27.4% of cases. Early neurological deterioration was monitored in 183 patients for 6 months to determine the surgical complications of ATPA. Consciousness disturbance recovered in half of the cases but persisted in 3 (1.5%). Hemiparesis fully recovered in 63.2% of cases, resulting in a complication rate of 3.0%. The most frequent complication was diplopia (36.4%), with a complete remission rate of 26.4%. The second most frequent complication was facial hypesthesia (24.0%), with a recovery rate of 16.1%. Facial nerve palsy improved in 63.0% of cases and had a complication rate of 4.9%. Cerebellar symptoms showed complete recovery in all cases. CONCLUSIONS: The ATPA allows the removal of petroclival tumors extending into Meckel's cave and the middle fossa, making it preferred for dumbbell trigeminal schwannomas and meningiomas. However, the ATPA's aggressive tumor removal can risk a lower recovery of cranial nerve IV-VI deficits. For benign meningiomas, initial observation with regular follow-up is recommended. Surgery is appropriate for high-growth cases aiming for total removal, accompanied by a thorough explanation of the risks. If the risks are not accepted, subtotal removal can be considered, and radiosurgery is suggested for residual tumor.

N-2,6-Di(isopropyl)phenyl-2-azaphenalenyl radical cations.

N-2,6-Di(isopropyl)phenyl-2-azaphenalenyl radical cations were obtained as a dark brown air-sensitive crystalline compound. The high HOMA values and the ACID calculation indicate relatively high aromatic character of a 5,8-di-tert-butyl derivative, and clean generation of a derivative without tert-butyl groups indicates that the di(isopropyl)phenyl group is sufficient for hampering the formation of the σ-dimer.

Anthracene-1,4,9,10-tetra-one.

The asymmetric unit of the title compound, C14H6O4, contains three independent mol-ecules (A, B and C). In mol-ecule C, there are two disordered sets of two carbonyl O atoms [occupancies = 0.643 (11) and 0.357 (11)]. All three mol-ecules are non-planar due to repulsion between two O atoms in peri positions on the anthracene ring, showing a slight difference in deviation of the carbonyl O atoms. The intra-molecular distances between the two nearest O atoms are in the range of 2.685 (10)-2.766 (10) Å. In the crystal, mol-ecules are linked by C-H⋯O and π-π [centroid-centroid distances = 3.615 (2), 3.844 (2) and 3.921 (2) Å] inter-actions, which lead to the formation of a herringbone-like arrangement.

Anterior Transpetrosal Approach: 2-Dimensional Operative Video.

INDICATIONS CORRIDOR AND LIMITS OF EXPOSURE: The anterior transpetrosal approach uses the subtemporal corridor to access the Meckel cave and the upper petroclival region from the dorsum sellae down to the cerebellopontine angle. ANATOMIC ESSENTIALS NEED FOR PREOPERATIVE PLANNING AND ASSESSMENT: The boundaries of posteromedial triangle of the middle fossa must be adequately visualized for the anterior petrosectomy. They are V3 anteriorly, the petrous ridge medially, GSPN laterally, and the meatal plane posteriorly. ESSENTIALS STEPS OF THE PROCEDURE: The position is supine with the head fully turned. After a temporal craniotomy, the dura is stripped off the floor of the middle fossa. The middle meningeal artery is coagulated and cut, and the greater superficial petrosal nerve is released to allow access to the petrous apex. The extent of the anterior petrosectomy is case-specific, tailored to the exposure needed. The posterior fossa dura is cut where exposed by the petrosectomy and the middle fossa dura just above level of the tentorium and parallel to it. The superior petrosal sinus is ligated and with tentorial incision up to the incisura, the approach is complete. PITFALLS/AVOIDANCE OF COMPLICATIONS: The contents of the petrous temporal bone, such as the cochlea and labyrinthine, and the point of crossing of the carotid artery under V3 must be examined preoperatively to avoid injury during drilling. VARIANTS AND INDICATIONS FOR THEIR USE: The anterior transpetrosal approach can be combined with other approaches to expand surgical access. Two examples of this are included in this video.The patients consented to the surgery and to publication of their images.Image at 0:36 from Kawase T, Toya S, Shiobara R, Mine T, Transpetrosal approach for aneurysm of the lower basilar artery, J Neurosurg , 1981;63(6):857-861, with permission from JNSPG; Image at 1:03 from Jean, Skull Base Surgery: Strategies, edition 1 (9781626239579), with permission from Thieme Publishers.

9,9-Bis[4-(N-aryl)phenyl]methylidene-xanthylidene Derivatives Displaying Mechano-, Crystallo-, and Thermochromism.

Tetraphenylethylene (TPE) derivatives bearing a xanthene moiety are of interest because they have novel optical properties. 9,9-Bis[4-(N,N-diphenylamino)phenyl] and 9,9-bis[4-(9-carbazolyl)-phenyl]methylidene-xanthylidenes 3 and 4 were synthesized using Suzuki-Miyaura coupling of 9,9-dibromomethylidene-xanthylidene with the corresponding boronic acids. Diphenylamino derivative 3 exhibits mechanochromism and mechanofluorochromism (MC and MFC) reflected in absorption and fluorescence color changes. In contrast, carbazolyl derivative 4 displays thermo- and crystallo-chromism in addition to MC and MFC in the solid state. Powder X-ray diffraction and single crystal X-ray crystallographic analysis reveal that the solid state photophysical properties of these substances are governed by conformational changes rather by the creation of planar π-conjugation extended geometries.

9,10-Diiodo-phenanthrene.

The whole mol-ecule of the title compound, C14H8I2, is generated by crystallographic twofold symmetry. The mol-ecule is planar [maximum deviation = 0.0323 (6) Å] with the I atoms displaced from the mean plane of the phenanthrene ring system by only 0.0254 (5) Å. In the crystal, mol-ecules form face-to-face slipped anti-parallel π-π stacking inter-actions along the c axis with an inter-planar distance of 3.499 (7) Å.

3,6-Dibromo-phenanthrene.

The phenanthrene ring in the title compound, C(14)H(8)Br(2), is approximately planar [maximum deviation = 0.039 (3) Å]. In contrast, the two bromo atoms are displaced slightly from the phenanthrene plane [maximum deviation = 0.1637 (3) Å]. In the crystal, the mol-ecules adopt a herringbone-like arrangement and form face-to-face slipped π-π stacking inter-actions along the b axis, with an inter-planar distance of 3.544 (3) Šand slippage of 1.81 Å. The crystal studied was a racemic twin with a minor twin fraction of 0.390 (10).

9,10-Dibromo-phenanthrene.

The mol-ecule of the title compound, C(14)H(8)Br(2), is almost planar [maximum deviation 0.0355 (7) Å] and possesses crystallographic twofold (C2) symmetry. In the crystal, the mol-ecules form face-to-face slipped anti-parallel π-π stacking inter-actions along the c axis with an inter-planar distance 3.471 (7) Å, centroid-centroid distances of 3.617 (5)-3.803 (6) Å.

2,6-Dimeth-oxy-9,10-anthraquinone.

The title compound, C(16)H(12)O(4), crystallizes with two half-mol-ecules in the asymmetric unit, each of which is completed by a crystallographic inversion center. The two crystallographically independent mol-ecules have almost the same geometry and are almost planar [maximum deviations = 0.018 (3) and 0.049 (3) Å]. They adopt a conformation in which the C(meth-yl)-O bonds are directed along the mol-ecular short axis [C-C-O-C torsion angles of 179.6 (2) and 178.0 (2)°]. In the crystal, the mol-ecular packing is characterized by a combination of a columnar stacking and a herringbone-like arrangement. The mol-ecules form slipped π-stacks along the b axis, in which there are two kinds of columns differing from each other in their slippage. The inter-planar distances between neighboring mol-ecules are 3.493 (3) for one column and 3.451 (2) Šfor the other.

2,3,6,7-Tetra-meth-oxy-9,10-anthra-quinone.

Mol-ecules of the title compound, C(18)H(16)O(6), are almost planar [maximum deviation = 0.096 (4) Å] and reside on crystallographic centres of inversion. They adopt a conformation in which the C(meth-yl)-O bonds are directed along the mol-ecular short axis [C-C-O-C torsion angles of -175.3 (3) and 178.2 (3)°]. In the crystal, mol-ecules adopt a slipped-parallel arrangement with π-π stacking inter-actions along the a axis with an inter-planar distance of 3.392 (4) Å. Weak C-H⋯O inter-actions link the mol-ecules into sheets parallel to (10-2).

Anterior transpetrosal approach: experiences in 274 cases over 33 years. Technical variations, operated patients, and approach-related complications.

OBJECTIVE: The anterior transpetrosal approach (ATPA) was initially reported in 1985. The authors' institution has 274 case records of surgery performed with the ATPA during the period from 1984 to 2017. Although many technical advances and modifications in the ATPA have occurred over those 33 years, to the authors' knowledge no articles to date have reported a detailed analysis of variations and complications of the ATPA. In this study, the authors analyzed their patient series to elucidate improvements over time in ATPA methodology while highlighting unresolved problems and evaluating how to avoid surgical complications. METHODS: All surgical cases (274 patients) using the ATPA at the authors' institution during the period from 1984 to 2017 were analyzed retrospectively using charts, clinical summaries, operative records, and operative videos. Obtained parameters were patient age and sex, diagnosis, size of tumors, location of disease, operative date, neurological symptoms before and after surgery, radiographically identified brain injury, and other surgical complications. The most common diagnosis was petroclival meningioma (n = 158), followed by trigeminal schwannoma (n = 32), chordoma (n = 25), epidermoid tumor (n = 21), other tumor (n = 27), aneurysm (n = 6), and other (n = 5). RESULTS: The original ATPA was performed in 239 cases. In an additional 35 cases, a modified ATPA was performed. Zygomatic osteotomy with ATPA was a common modification that was used in 19 of the 35 cases to decrease retraction damage to the temporal lobe for high-positioned tumors. Brain injury by temporal lobe retraction without venous hemorrhage still occurred in 8 of the 19 cases (3.1%) with surgical death in 1 of these cases (0.4%) of reoperation with sacrifice of the petrosal vein. Symptomatic CSF leak was the most frequent complication noted and was observed in 35 cases (13.5%). In most of these cases the patients were cured by observation or lumbar drain, but in 6 cases (17.1%) reoperation was needed. Facial nerve damage related to surgical approach decreased from 6.2% to 3.5% after 2010; however, the incidence of CSF leaks (13.5%) has not improved. CONCLUSIONS: There have been several modifications and advancements made in the ATPA to increase tumor removal and decrease surgical complications. However, complications related to surgical approach occurred, such as venous occlusion-related brain injury and facial nerve damage at pyramid resection. CSF leak remained an unsolved problem related to the ATPA procedures. Preoperative assessment of venous variation of the middle fossa, pneumatization of the temporal bone, and intraoperative monitoring of cranial nerves are important procedures to decrease these complications.

Management of cavernous sinus meningiomas: Consensus statement on behalf of the EANS skull base section.

Introduction: The evolution of cavernous sinus meningiomas (CSMs) might be unpredictable and the efficacy of their treatments is challenging due to their indolent evolution, variations and fluctuations of symptoms, heterogeneity of classifications and lack of randomized controlled trials. Here, a dedicated task force provides a consensus statement on the overall management of CSMs. Research question: To determine the best overall management of CSMs, depending on their clinical presentation, size, and evolution as well as patient characteristics. Material and methods: Using the PRISMA 2020 guidelines, we included literature from January 2000 to December 2020. A total of 400 abstracts and 77 titles were kept for full-paper screening. Results: The task force formulated 8 recommendations (Level C evidence). CSMs should be managed by a highly specialized multidisciplinary team. The initial evaluation of patients includes clinical, ophthalmological, endocrinological and radiological assessment. Treatment of CSM should involve experienced skull-base neurosurgeons or neuro-radiosurgeons, radiation oncologists, radiologists, ophthalmologists, and endocrinologists. Discussion and conclusion: Radiosurgery is preferred as first-line treatment in small, enclosed, pauci-symptomatic lesions/in elderly patients, while large CSMs not amenable to resection or WHO grade II-III are candidates for radiotherapy. Microsurgery is an option in aggressive/rapidly progressing lesions in young patients presenting with oculomotor/visual/endocrinological impairment. Whenever surgery is offered, open cranial approaches are the current standard. There is limited experience reported about endoscopic endonasal approach for CSMs and the main indication is decompression of the cavernous sinus to improve symptoms. Whenever surgery is indicated, the current trend is to offer decompression followed by radiosurgery.

Functional analysis of HOXD9 in human gliomas and glioma cancer stem cells.

BACKGROUND: HOX genes encode a family of homeodomain-containing transcription factors involved in the determination of cell fate and identity during embryonic development. They also behave as oncogenes in some malignancies. RESULTS: In this study, we found high expression of the HOXD9 gene transcript in glioma cell lines and human glioma tissues by quantitative real-time PCR. Using immunohistochemistry, we observed HOXD9 protein expression in human brain tumor tissues, including astrocytomas and glioblastomas. To investigate the role of HOXD9 in gliomas, we silenced its expression in the glioma cell line U87 using HOXD9-specific siRNA, and observed decreased cell proliferation, cell cycle arrest, and induction of apoptosis. It was suggested that HOXD9 contributes to both cell proliferation and/or cell survival. The HOXD9 gene was highly expressed in a side population (SP) of SK-MG-1 cells that was previously identified as an enriched-cell fraction of glioma cancer stem-like cells. HOXD9 siRNA treatment of SK-MG-1 SP cells resulted in reduced cell proliferation. Finally, we cultured human glioma cancer stem cells (GCSCs) from patient specimens found with high expression of HOXD9 in GCSCs compared with normal astrocyte cells and neural stem/progenitor cells (NSPCs). CONCLUSIONS: Our results suggest that HOXD9 may be a novel marker of GCSCs and cell proliferation and/or survival factor in gliomas and glioma cancer stem-like cells, and a potential therapeutic target.

Downregulation of uPARAP mediates cytoskeletal rearrangements and decreases invasion and migration properties in glioma cells.

To identify molecular therapeutic targets for glioma, we performed gene expression profiling by using a complementary DNA (cDNA) microarray method and identified the urokinase plasminogen activator receptor-associated protein (uPARAP/Endo180) as a gene expressed highly in glioma tissue compared with the normal brain tissue. The uPARAP is an endocytic receptor for collagen. In certain cell types, uPARAP occurs in a complex with the urokinase plasminogen activator receptor (uPAR) where it fulfills other functions in addition to collagenolysis. Quantitative PCR analysis using a cDNA panel revealed higher expression levels of uPARAP in glioma tissue compared with normal brain tissue. Western blot analysis revealed that the uPARAP protein was expressed in glioma samples and two glioma cell lines, KNS42 and KNS81, but not expressed in control tissue from the normal brain. Introduction of small interfering RNA-targeted uPARAP into the two different glioma cell lines, KNS42 and KNS81, resulted in downregulation of uPARAP expression, and it significantly suppressed glioma cell migration and invasion in vitro. Control glioma cells showed small cell bodies, whereas uPARAP siRNA-treated glioma cells exhibited large and flat morphology. Most of the polymeric actin in the control glioma cells was concentrated in the lamellipodia that are observed in mobile cells. In contrast, in the uPARAP siRNA-treated glioma cells, polymeric actin became organized in stress fibers and the lamellipodia disappeared, characteristic of immobile cells. Our present study suggests that uPARAP may be involved in glioma cell invasiveness through actin cytoskeletal rearrangement. downregulation of uPARAP may be a novel anti-invasion therapeutic strategy for malignant gliomas.

Critical roles of NK and CD8+ T cells in central nervous system listeriosis.

Listeria monocytogenes (LM) causes a life-threatening infectious disease affecting the brain of humans and domestic animals. Unfortunately, no adequate murine models for CNS listeriosis exist. Using intraparenchymal injection, we have established a new murine model for CNS listeriosis. Injection of a small volume of bacterial suspension limits the bacteria to the brain parenchyma with no leakage into the ventricular system. This new method enabled us to investigate the progression of and recovery from listerial brain infection, revealing roles for both innate and adaptive immune cells in CNS listeriosis. In the early phase of CNS listeriosis, NK cell-derived IFN-gamma is a critical cytokine in the limitation of bacterial growth by the host defense. During the later phase, CD8(+) but not CD4(+) T cells play a critical role and LM-specific CD8(+) T cells kill LM-infected microglia. Thus, innate and adaptive immune responses combine to successfully eliminate bacteria from the brain.

"Marking" the nitrogen atoms of phenyl-(2-pyridyl)-(3-pyridyl)-(4-pyridyl)-methane. Synthesis and absolute configuration of the corresponding tris(pyridine N-oxide).

To "mark" the nitrogen atoms in phenyl-(2-pyridyl)-(3-pyridyl)-(4-pyridyl)methane (1), we have synthesized the corresponding tris(pyridine N-oxide) 2 by oxidation of 1 with m-chloroperbenzoic acid. The nitrogen atoms of 2 are unequivocally determined by the X-ray crystal analysis of a single crystal of rac-2 whereas the nitrogen atoms cannot be assigned at all in the case of rac-1. N-Oxide 2 can be resolved by chiral high-performance liquid chromatography under similar conditions to those used for the resolution of 1. The calculated circular dichroism (CD) curve for (R)-2 on the basis of time-dependent density functional theory reproduces the experimental spectra very well to suggest that the second-eluted fraction ([CD(+)283]-2) is the R isomer, namely (R)-[CD(+)283]-2. The independent absolute configuration determinations for 1 and 2 are in keeping with the chemical correlation between the two compounds by oxidation of (R)-1 into (R)-2.

1,7-Diethyl-4,10-diisopropyl-tetra-cene.

The mol-ecule of the title compound, C(28)H(32), is located on a crystallographic inversion center. The ethyl groups are essentially coplanar with the tetra-cene ring, making a torsion angle of -0.4 (4)°. The isopropyl groups adopt an asymmetric conformation with their terminal methyl groups positioned on opposite sides of the tetra-cene plane [the Me-C-C-C torsion angles are -22.5 (4) and 100.9 (3)°]. In the crystal, the mol-ecules adopt an arrangement without significant π-π inter-actions along the stacking direction (y axis).