[Nonspecific craniovertebral spondylitis]. / Nespetsificheskie spondility kraniovertebral'noi oblasti.

OBJECTIVE: To analyze surgical strategy for nonspecific spondylitis of the craniovertebral region (CVR) taking into account clinical features and morphological signs of disease. MATERIAL AND METHODS: Eight patients with nonspecific spondylitis of CVR underwent surgery (4 women and 4 men aged 31-75 years). Three patients had pain syndrome, 5 ones - conduction disorders. Combined interventions were performed in 5 patients with neurological disorders. Of these, 3 patients underwent transoral decompression with subsequent occipitospondylodesis. In other cases, stages of surgical treatment were reverse. Four patients underwent simultaneous interventions, 1 patient - with 7-day interval. Patients with pain syndrome underwent occipitospondylodesis. RESULTS: In all patients, postoperative VAS score of pain syndrome decreased by 5-7 points (mean 5.5). Among 5 patients with conduction symptoms, regression of neurological disorders 1 year after surgery was achieved in 2 cases, and complete recovery was observed in 3 patients (Frankel E). In all cases, examination confirmed relief of inflammatory process and no compression of the spinal cord and medulla oblongata. One patient had a dehiscence of the wound edges of posterior pharyngeal wall, and another one had implant fracture in 3 years after surgery. CONCLUSION: Active surgical approach is reasonable for nonspecific spondylitis of CVR. Craniocervical fixation eliminates pain and risk of neurological complications following atlantoaxial instability. Conduction disorders require simultaneous transoral decompression and occipitospondylodesis in patients with nonspecific purulent craniovertebral lesions. Impaired head tilt complicates transoral stage. In this regard, it is more rational to carry out craniocervical fixation at the last stage.

Intramolecular rate-constant calculations based on the correlation function using temperature dependent quantum Green's functions.

A theoretical method for calculating rate constants for internal conversion (IC), intersystem crossing (ISC) and radiative (R) electronic transitions is presented. The employed method uses temperature-dependent quantum Green's functions, which give the opportunity to consider almost any nth-order polynomial perturbation operator and the influence of external electromagnetic fields on the rate constants. The rate constants of the IC, ISC and R processes are calculated for two important indocyanine molecules namely indocyanine green (ICG) and heptamethine cyanine (IR808) at the Franck-Condon level using the temperature-dependent quantum Green's function approach. Calculations at the time-dependent density functional theory level with the MN15 functional show that ICG and IR808 have only one triplet state below the S1 state. The main deactivation channel of the S1 state is the IC process with a large (kIC(S1 → S0)) rate constant of ∼109-1011 s-1. The estimated quantum yield of fluorescence (φfl) is ∼0.001-0.24 for the two studied molecules, which agrees rather well with experimental values. Thus, the present approach enables calculations of the three kinds of rate constants and the quantum yield of fluorescence using the same computational methodology.

Internal conversion induced by external electric and magnetic fields.

We have developed a new methodology for calculating contributions to the rate constants (kIC) of internal conversion that are induced by external electric (kIC-E) or magnetic (kIC-M) fields. The influence of the external electric and magnetic fields on the kIC was estimated for seven representative molecules. We show that the kIC-E contribution calculated at a field strength of 1011 V m-1 is generally as large as the kIC rate constant in the absence of the external field. For indocyanine green, azaoxa[8]circulene, and pyromitene 567, the kIC-E contribution is as large as kIC already at a field strength of 109 V m-1. Such electric-field strengths occur for example in plasmonic studies and in strong laser-field experiments. The induced effect on the kIC rate constant should be accounted for in calculations of photophysical properties of molecules involved in such experiments. The induced effect of an external magnetic field on kIC can be neglected in experiments on Earth because the magnetic contribution becomes significant only at very strong magnetic fields of 104-105 T that cannot be achieved on Earth. However, the magnetic effect on the rate constant of internal conversion can be important in astrophysical studies, where extremely strong magnetic fields occur near neutron stars and white dwarfs.

[Total resection of aggressive hemangioma of thoracic spine: case report and literature review]. / Total'noe udalenie agressivnoi gemangiomy grudnogo otdela pozvonochnika (klinicheskoe nablyudenie i obzor literatury).

The authors report total resection of aggressive hemangioma of Th7 vertebra in a patient with severe conduction disorders in the lower extremities. Total Th7 spondylectomy (Tomita procedure) was performed. This method provided simultaneous en bloc resection of the vertebra and tumor via the same approach, eliminate spinal cord compression and perform stable circular fusion. Postoperative follow-up period was 6 months. Neurological disorders were evaluated using the Frankel scale, pain syndrome - visual analogue scale, muscle strength - MRC scale. Pain syndrome and motor disorders in the lower extremities regressed in 6 months after surgery. CT confirmed spinal fusion without signs of continued tumor growth. Literature data on surgical treatment of aggressive hemangiomas are reviewed.

[Skip corpectomy in surgical treatment of cervical spondylotic myelopathy]. / Metod «skip corpectomy¼ pri khirurgicheskom lechenii tservikal'noi spondilogennoi mielopatii.

OBJECTIVE: To evaluate the effectiveness and safety of skip corpectomy in surgical treatment of cervical spondylotic myelopathy. MATERIAL AND METHODS: The study included 7 patients with cervical myelopathy following extended cervical spine stenosis. All patients underwent skip corpectomy. Clinical examination included degree of neurological disorders according to the modified scale of the Japanese Orthopedic Association (JOA) with assessment of recovery rate and Nurick score, as well as VAS score of pain syndrome. Verification of diagnosis was based on the data of spondylography, magnetic resonance and computed tomography. The indications for surgical treatment were conduction disorders and their spondylotic genesis confirmed by neuroimaging methods. RESULTS. VAS: Score of pain syndrome decreased by 2-4 points (mean 3.1) in long-term postoperative period. The JOA, Nurick scores and recovery rate (mean 42.5%) demonstrated significant improvement of neurological status in all patients. In all cases, the follow-up examination confirmed adequate decompression and spinal fusion. CONCLUSION: Skip corpectomy provides adequate spinal cord decompression in case of extended cervical spine stenosis and minimizes the risk of complications typical for multilevel corpectomy. Recovery rate indicates the effectiveness of this method in surgical treatment of cervical myelopathy caused by multilevel stenosis. However, further studies on sufficient clinical material are needed.

Internal conversion rate constant calculations considering Duschinsky, anharmonic and Herzberg-Teller effects.

A novel method for calculating rate constants for internal conversion (kIC) that simultaneously accounts for Duschinsky, anharmonic and Herzberg-Teller effects has been developed and implemented. This method has been applied to robust planar molecules like tetraoxa[8]circulene (4B), free-base porphyrin (H2P) and pyrometene (PM567) with small Duschinsky rotation (i.e. with almost identical normal coordinates in the ground and excited states) and to poly[n]fluorenes (P[n]F) (n = 2-14) with a substantial Duschinsky rotation. The obtained results show that the Duschinsky effect is large in the harmonic approximation, whereas it is in general much smaller in the anharmonic approximation. The Duschinsky effect is found to be large for high frequency vibrational modes with energies of ∼3300 cm-1 such as the X-H (X = C, N and O) stretching modes that mix in the S1 → S0 electronic transition. However, even in this case, the increase in kIC due to the Duschinsky effect does not exceed one order of magnitude. The calculations show that anharmonic contributions to kIC are larger than Herzberg-Teller contributions which in turn are larger than contributions from the Duschinsky effect ANH > HT > Du. We also show that an approximation, where only X-H bonds are considered in the kIC calculation, is accurate even for P[n]F (n = 2-14).

[En-bloc resection of giant neuroma of thoracic spine via transthoracic extrapleural access: a case report and literature review]. / Blok-rezektsiya gigantskoi nevrinomy grudnogo otdela pozvonochnika s ispol'zovaniem transtorakal'nogo ekstraplevral'nogo dostupa: redkoe klinicheskoe nablyudenie i obzor literatury.

The authors describe surgical treatment of a patient with giant neuroma of thoracic spine. The patient underwent en-bloc resection of tumor via transthoracic extrapleural access. Technical nuances of surgery and operational capabilities of transthoracic extrapleural access for resection of neurogenic tumors of posterior mediastinum are demonstrated. Capabilities of transthoracic extrapleural access are comparable to thoracotomy. The first experience of transthoracic extrapleural access showed its effectiveness in resection of giant neuromas of thoracic spine. Indisputable advantage of this access is less surgical injury compared to thoracotomy. A brief literature review is presented.

[Surgical treatment of herniated thoracic discs using transthoracic extrapleural approach]. / Khirurgicheskoe lechenie gryzh grudnykh mezhpozvonkovykh diskov s ispol'zovaniem transtorakal'nogo ekstraplevral'nogo dostupa.

OBJECTIVE: To analyze the results of herniated thoracic disc resection via transthoracic extrapleural approach. MATERIAL AND METHODS: The study included 16 patients with 18 symptomatic herniated thoracic discs wo underwent transthoracic extrapleural surgery. In 11 cases, clinical pattern of disease was represented by myelopathy with radicular or axial pain syndrome. Five patients had radiculopathy alone. Median localization of hernias was observed in 8 (44.4%) cases, paramedian hernias - in 10 (55.6%) cases. There were 10 (55.6%) ossified hernias, 5 (27.7%) giant, 10 (55.5%) large and 3 (16.6%) medium hernias. RESULTS: In most patients, VAS score of pain syndrome decreased by 2-6 points (mean 3.6). In 4 patients, this value remained the same. Among 11 patients with myelopathy, regression of conduction disorders in 1 year after surgery was achieved in 9 (82%) cases including complete recovery in 6 (55%) patients (Frankel E, Nurick - 0-I). In 2 patients, neurological status was equal to preoperative one. In all cases, the follow-up examination confirmed total removal of compressive substrate and found no signs of spine instability. Surgery time varied from 80 to 210 min (mean 161), blood loss - from 300 to 800 ml (mean 378 ml). Two patients had transient neurological deterioration. There was damage to dura mater in 4 cases. Intercostal neuralgia was observed in 3 patients. CONCLUSION: While retaining the advantages of open thoracotomy, transthoracic extrapleural approach is less traumatic, allows complete spinal cord decompression, minimizes the risk of iatrogenic spinal cord injury and avoids certain postoperative complications.

[Successful surgical treatment of patient with cervical myelopathy due to ossification of the posterior longitudinal ligament: a rare clinical observation and literature review]. / Uspeshnoe khirurgicheskoe lechenie patsienta s tservikal'noi mielopatiei na fone ossifikatsii zadnei prodol'noi svyazki: redkoe klinicheskoe nablyudenie i obzor literatury.

The authors describe the result of combined surgical treatment of a patient with symptomatic multiple-level cervical spine stenosis following ossification of posterior longitudinal ligament. The first stage included decompressive laminectomy and cervical spine fusion using a screw. At the second stage, CIV-CV-CVI-CVII corporectomy with total resection of the ossified posterior longitudinal ligament and CIII-ThI corporodesis with a bone autograft were carried out. This approach was valuable to minimize the risk of iatrogenic damage to the spinal cord, eliminate long spinal stenosis and perform circular fusion of the cervical spine. These measures led to regression of cervical myelopathy symptoms. A brief review is presented.

Fast estimation of the internal conversion rate constant in photophysical applications.

An efficient method for estimating non-adiabatic coupling matrix elements (NACME) and rate constants for internal conversion (kIC) is presented. The method, based on Plotnikov's theory, requires only calculations of the electronic wave functions and the corresponding electronic excitation energies. Computationally expensive calculations of the derivatives of the electronic wave function with respect to the nuclear coordinates are avoided. When the main accepting modes of the electronic excitation energy are X-H vibrations, the present method can be used for estimating the efficiency of the energy transfer between donor and acceptor molecules. It can also be used in studies of the influence of hydrogen bonding or solvent effect on fluorescence quenching, in studies of vibronic effects of TADF (thermally activated delayed fluorescence) emitters, and for calculating kIC. Here, kIC and NACME are calculated for free-base porhyrin, magnesium porphyrin, azulene, naphthalene, pyrene and fluorenone interacting with a solvent molecule. Reverse kIC and NACME are further calculated for the T1→ T2 transition of dibenzothiophene-S,S-dioxide (PTZ-DBTO2), which is used in TADF applications. Finally, we estimate the efficiency of the energy transfer between two large porphyrinoid dimers.

The effect of 2D tungsten disulfide nanoparticles on Lewis lung carcinoma cells in vitro.

The unique physicochemical properties of modern two-dimensional (2D) nanomaterials with graphene-like structures make them promising candidates for biology and medicine purposes. In this article, we investigate the influence of the two-dimensional tungsten disulfide (2D WS2) water suspension nanoparticles obtained by an improved mechanochemical method from powdered WS2 on morphological and structural characteristics of Lewis lung carcinoma cells using FT-IR, Raman spectroscopy, and confocal microscopy. The characterization of the 2D WS2 nanoparticles by different physical methods is given also. We have highlighted that 2D WS2 does not exert cytotoxic activity in the case of 1 day incubation with tumor cells. Prolongation of the incubation period up to 2 days has caused a statistically significant (p < 0.05) concentration-dependent decrease of the number of viable cells by more than 30% with the maximum cytotoxic effect at concentrations of 2D WS2 close to 2 µg ml-1. In the Raman spectra of 2D WS2 treated cells the bands centered at 354 cm-1 and 419 cm-1, which are assigned to characteristics and modes of WS2 nanoparticles were observed. The obtained data indicate, that the cytotoxic effect of 2D WS2 on tumor cells in the case of long-term incubation is realized particularly through the ability of 2D WS2 to enter tumor cells and/or accumulate on their surface, which gives a rationale to conduct further studies of their antitumor efficacy in vitro and in vivo when combined with chemotherapeutic drugs.

First-principles calculations of anharmonic and deuteration effects on the photophysical properties of polyacenes and porphyrinoids.

A new method for calculating internal conversion rate constants (k[combining low line]IC), including anharmonic effects and using the Lagrangian multiplier technique, is proposed. The deuteration effect on k[combining low line]IC is investigated for naphthalene, anthracene, free-base porphyrin (H2P) and tetraphenylporphyrin (H2TPP). The results show that anharmonic effects are important when calculating k[combining low line]IC for transitions between electronic states that are energetically separated (ΔE) by more than 20 000-25 000 cm-1. Anharmonic effects are also important when ΔE < 20 000-25 000 cm-1 and when the accepting modes are X-H stretching vibrations with a frequency larger than 2000 cm-1. The calculations show that there is mixing between the S1 and S2 states of naphthalene induced by non-adiabatic interactions. The non-adiabatic interaction matrix element between the S1 and S2 states is 250 cm-1 and 50 cm-1 for the normal and fully deuterated naphthalene structure and this difference significantly affects the estimated fluorescence quantum yield. Besides aromatic hydrocarbons H2P and H2TPP, the k[combining low line]IC rate constant is also calculated for pyrometene (PM567) and tetraoxa[8]circulene (4B) with a detailed analysis of the effect of the vibrational anharmonicity.

Aromaticity and photophysics of tetrasila- and tetragerma-annelated tetrathienylenes as new representatives of the hetero[8]circulene family.

The electronic structure, absorption and emission spectra, aromaticity and photophysical behavior of the recently synthesized tetrasilatetrathia[8]circulene and tetragermatetrathia[8]circulene compounds have been studied computationally. Both compounds demonstrate a specific bifacial aromaticity, which is unusual for hetero[8]circulenes; the inner eight-membered core sustains an expected strong paratropic magnetically-induced ring current, while the outer perimeter contains saturated Si(Et)2 and Ge(Et)2 moieties which break the conjugation between the thiophene rings. The overall magnetically-induced ring current for both studied circulenes is close to zero because of the strong local diatropic currents in each thiophene ring that compensate the paratropic counterpart. The electronic absorption and emission spectra of tetrasilatetrathia[8]circulene and tetragermatetrathia[8]circulene demonstrate a clear visible vibronic progression. The 0-0 band is the most active one in the absorption spectra, while in the fluorescence spectra the 0-1 band composed of several normal vibrations is more intense compared with the 0-0 band in excellent agreement with experiment. Accounting for spin-orbit coupling effects, an analysis of the photophysical constants for the two compounds demonstrates: (1) a clear manifestation of the internal heavy atom effect on the inter-system crossing efficiency; (2) one to two order domination of non-radiative rates over the fluorescence rate; and (3) that the S1-S0 internal conversion is extremely slow and can not compete with the fluorescence, while the S1-Tn inter-system crossing is a main deactivation channel of the S1 excited state. These results provide new insight into the electronic structure and photophysics of tetrasilatetrathia[8]circulene and tetragermatetrathia[8]circulene as novel standalone representatives of hetero[8]circulenes - tetraannelated derivatives of tetrathienylene.

First-principles method for calculating the rate constants of internal-conversion and intersystem-crossing transitions.

A method for calculating the rate constants for internal-conversion (kIC) and intersystem-crossing (kISC) processes within the adiabatic and Franck-Condon (FC) approximations is proposed. The applicability of the method is demonstrated by calculation of kIC and kISC for a set of organic and organometallic compounds with experimentally known spectroscopic properties. The studied molecules were pyrromethene-567 dye, psoralene, hetero[8]circulenes, free-base porphyrin, naphthalene, and larger polyacenes. We also studied fac-Alq3 and fac-Ir(ppy)3, which are important molecules in organic light emitting diodes (OLEDs). The excitation energies were calculated at the multi-configuration quasi-degenerate second-order perturbation theory (XMC-QDPT2) level, which is found to yield excitation energies in good agreement with experimental data. Spin-orbit coupling matrix elements, non-adiabatic coupling matrix elements, Huang-Rhys factors, and vibrational energies were calculated at the time-dependent density functional theory (TDDFT) and complete active space self-consistent field (CASSCF) levels. The computed fluorescence quantum yields for the pyrromethene-567 dye, psoralene, hetero[8]circulenes, fac-Alq3 and fac-Ir(ppy)3 agree well with experimental data, whereas for the free-base porphyrin, naphthalene, and the polyacenes, the obtained quantum yields significantly differ from the experimental values, because the FC and adiabatic approximations are not accurate for these molecules.

Inducing Hepatitis C Virus Resistance After Pig Liver Transplantation-A Proof of Concept of Liver Graft Modification Using Warm Ex Vivo Perfusion.

Normothermic ex vivo liver perfusion (NEVLP) offers the potential to optimize graft function prior to liver transplantation (LT). Hepatitis C virus (HCV) is dependent on the presence of miRNA(microRNA)-122. Miravirsen, a locked-nucleic acid oligonucleotide, sequesters miR-122 and inhibits HCV replication. The aim of this study was to assess the efficacy of delivering miravirsen during NEVLP to inhibit miR-122 function in a pig LT model. Pig livers were treated with miravirsen during NEVLP or cold storage (CS). Miravirsen absorption, miR-122 sequestration, and miR-122 target gene derepression were determined before and after LT. The effect of miravirsen treatment on HCV infection of hepatoma cells was also assessed. NEVLP improved miravirsen uptake versus CS. Significant miR-122 sequestration and miR-122 target gene derepression were seen with NEVLP but not with CS. In vitro data confirmed miravirsen suppression of HCV replication after established infection and prevented HCV infection with pretreatment of cells, analogous to the pretreatment of grafts in the transplant setting. In conclusion, miravirsen delivery during NEVLP is a potential strategy to prevent HCV reinfection after LT. This is the first large-animal study to provide "proof of concept" for using NEVLP to modify and optimize liver grafts for transplantation.

Structural self-organization of C60 and cisplatin in physiological solution.

The specific features of structural self-organization of C60 fullerene and antitumor drug cisplatin (Cis) in physiological solution (0.9% NaCl) have been investigated by means of small-angle neutron scattering, scanning electron and atomic force microscopies, as well as isothermal titration calorimetry, dynamic light scattering and UV-Vis spectroscopy. The formation of C60 + Cis complexes, has been reported, unveiling the mechanism of medico-biological synergy observed during administration of the mixture of these drugs.

Scanning tunneling potentiometry implemented into a multi-tip setup by software.

We present a multi-tip scanning tunneling potentiometry technique that can be implemented into existing multi-tip scanning tunneling microscopes without installation of additional hardware. The resulting setup allows flexible in situ contacting of samples under UHV conditions and subsequent measurement of the sample topography and local electric potential with resolution down to Å and µV, respectively. The performance of the potentiometry feedback is demonstrated by thermovoltage measurements on the Ag/Si(111)-(√3×√3)R30° surface by resolving a standing wave pattern. Subsequently, the ability to map the local transport field as a result of a lateral current through the sample surface is shown on Ag/Si(111)-(√3×√3)R30° and Si(111) - (7 × 7) surfaces.

Anti-fibrillogenic properties of phthalocyanines: effect of the out-of-plane ligands.

The axially-coordinated phthalocyanines were previously reported as agents possessing strong anti-fibrillogenic properties. In the presented study we used the atomic force microscopy to investigate the intermediates and the products of insulin aggregation reaction formed in the presence of Zr and Hf phthalocyanine complexes that contain out-of-plane ligands of different size and nature. It is shown that while phthalocyanine-free insulin generated mostly amyloid fibrils with a diameter of 2-8nm and a length of up to 5µm, the presence of phthalocyanines with spatial bulky ligands (PcZrDbm2) leads to the redirection of the fibrillization reaction to the formation of the spherical oligomer aggregates with a diameter of 4-12nm. At the same time the phthalocyanine complex PcHfCl2 having the small-volume ligands induces the formation of large size insulin aggregates with a height of about 100nm that are supposed to be amorphous species. The study of the aggregation intermediates showed the certain similarity of the reaction passing for phthalocyanine-free insulin and insulin in the presence of PcZrDbm2. The large-size amorphous species were observed at the beginning of reaction, later they dissociated, leading to the formation and growth of the smaller size particles. The amyloid-sensitive cyanine dye 7519 demonstrates the strong fluorescent response both in the presence of fibrils and spherical oligomers, while it is non-sensitive to amorphous aggregates.

Characterization of C60 fullerene complexation with antibiotic doxorubicin.

The aim of this paper was to provide the physico-chemical characterization of a key process leading to amplification of the antitumor effect of antibiotic Doxorubicin (Dox) in vivo and in vitro and occurring at the molecular level through complexation with C60 fullerene. A wide range of physico-chemical tools was used such as UV/Vis and NMR spectroscopies, atomic force microscopy, isothermal titration calorimetry and zeta-potential methods. The unusual thermodynamic behavior of the complexation process was reported, featuring unexpected and, to a certain extent, contradictory experimental observations. The explanation of the obtained results was proposed resulting in creation of a general view on aromatic drug binding with C60 fullerene. Based on these results some important practical outcomes for anticancer therapy were formulated.

[Tactics of surgical treatment of degenerative-dystrophic lesions of the lumbosacral spine in case of HIP-SPINE-syndrome].

The objective of this study is definition of surgical treatment tactics of multilevel degenerative-dystrophic lesions of the lumbosacral spine in case of HIP-SPINE-syndrome. It was presented the experience of surgical treatment of multilevel degenerative-dystrophic lesions of the lumbosacral spine in 52 patients aged from 48 to 81 years. Lumbar stenosis prevailed in 38 (73.1%) cases. There was degenerative spondylolisthesis in 9 (17.3%) cases, and degenerative scoliosis was detected in 5 (9.6%) patients. Different types of decompressive-stabilizing interventions according to direction of compression and the presence of degenerative instability were performed in all patients. Evaluation of surgical treatment was done by using of visual analog scale and questionnaire Oswestry Disability Index. It was revealed significant improvement of life quality by reducing of pain and increasing of daily activity. Maximal time of observation was 36 months.