Shear wave propagation in a liquid crystal: An inelastic X-ray scattering study.

We investigated the spectrum of density fluctuations of a liquid crystal, CB7CB, in two different orientations by using high-resolution inelastic x-ray scattering. Our analysis, based on Bayesian principles, revealed that high-frequency collective excitations propagate through this mesoscale-ordered sample in a peculiar manner that lies somewhere between those observed in liquids and crystalline systems. Interestingly, when we probed longer length scales, a more pronounced solid-like response emerged. This was mainly characterized by anomalously sharp inelastic excitations and the onset of shear mode propagation. Comparison with previous x-ray diffraction results suggests a correlation between the observed behavior and the mesogen arrangement.

Gut microbiota, a potential cause of higher insulin sensitivity in children with Prader-Willi syndrome.

PURPOSE: Obesity is the main driving factor for comorbidities in Prader-Willi syndrome (PWS) patients due to overeating behaviors. The gut microbiota has been implicated in the etiology of obesity and associated comorbidities. The purpose of the present study was to characterize the fecal microbiota in Chinese patients with PWS and compare it to that of patients with obesity as well as healthy controls. METHODS: We conducted a cross-sectional study with 35 PWS patients (PWS), 35 patients with obesity (OB), and 35 healthy controls (HC). Metagenomic sequencing was performed in stool samples. RESULTS: The composition of the fecal microbiota in PWS patients differed from that of participants in the OB and HC groups. It was characterized by increased Akkermansia Eubacterium, Eubacterium rectale, and Roseburia intestinalis and decreased Parabacteroides and Phascolarctobacterium. Additionally, the homeostatic model assessment of insulin resistance (HOMA-IR) was lower in PWS patients than in patients with obesity. Spearman rank correlation analysis showed that Achromobacter, Acidiphilium, Xylophilus, and Frisingicoccus were significantly negatively correlated with HOMA-IR. CONCLUSION: The composition of the gut microbiota in Chinese PWS patients differed from that in patients with obesity, which might contribute to higher insulin sensitivity in PWS patients.

[Advances in clinical prediction scores for prognosis of coronavirus disease-2019].

Coronavirus Disease-2019 (COVID-19) has been a major public health issue all over the world, placing a significant burden on available healthcare resources. The most common types of COVID-19 are the mild and common forms. Although the proportion of the severe-critical types is smaller, the rate of death is significantly higher and the medical resources required tend to be greater. Thus, a variety of scores based on other disease and COVID-19 were used to assess the risk of poor prognosis on the COVID-19, including the common scores for community-acquired pneumonia, sepsis and viral pneumonia. Unfortunately, the above scores often lacked an adequate description of the applicable population or were at high risk of bias with unknown applicability. Therefore, the article summarized the existing scores, aiming to provide a reference for clinical prognostic risk assessment.

[Clinical analysis of pulmonary nocardiosis associated with bronchiectasis].

Objective: To better understand the clinical characteristics of pulmonary nocardiosis associated with bronchiectasis. Methods: Patients diagnosed as bronchiectasis complicated with pulmonary nocardiosis in 9 tertiary general hospitals in China were enrolled from March 2016 to March 2020, with the record of general data, imaging performance and pathogen. The literature was reviewed. Results: Totally 17 patients were included. There were 12 females and 5 males. The ages ranged from 45 to 79 years, with an average of (63±9) years. There were 15 nonsmokers and 2 smokers, all of whom with chronic course. The clinical manifestations were mostly cough, expectoration, hemoptysis, fever, and dyspnea. The imaging manifestation was bronchiectasis in both lungs, with the most common involvement in the left lower lung, right middle lobe and left lingual lobe. Sputum cultures were positive in 10 cases, bronchoalveolar lavage fluid (BALF) cultures were positive in 6 cases, and next generation gene sequencings were positive in 4 cases, including 2 cases of Nocardia gelsenkii, 2 cases of Nocardia abscess, 2 cases of Nocardia stellate, 1 case of Nocardia mexicana, 1 case of Nocardia otitis caviae, and 9 cases of undetermined Nocardia. There were 3 cases of Klebsiella pneumoniae, 2 cases of Pseudomonas aeruginosa and 2 cases of Aspergillus. The symptoms and imaging of all patients were improved after anti Nocardia therapy. Conclusions: Bronchiectasis combined with nocardiosis is more common in middle-aged and elderly women without smoking, which is similar to the clinical manifestations of Lady Windermere syndrome. Bronchiectasis often involves the left lower lobe, right middle lobe and left lingual lobe. Nocardia infection might further precipitate the initiation and progression of bronchiectasis.

The impact of diabetes mellitus on mortality and infection outcomes in burn patients: a meta-analysis.

OBJECTIVE: Burns are one of the most commonly occurring soft tissue injuries worldwide. It has been reported that burns are associated with a higher prevalence of complications, mortality, and hospitalization-related outcomes in patients with coexisting diabetes mellitus. Moreover, the morbidity and mortality related outcomes associated with diabetes in patients with burns. However, since then, several studies reporting the prognostic role of diabetes in patients with burns have been published. Therefore, in this present study, we attempt to develop a current state of evidence evaluating the prognostic influence of diabetes mellitus on infectious complications, duration of hospital stay and mortality-related outcomes in patients with burns. The aim of the study is to determine the overall effect of diabetes mellitus on infectious complications, duration of hospital stay and mortality-related outcomes in patients with burns. MATERIALS AND METHODS: We performed a systematic search of the academic literature in four academic databases including EMBASE, CENTRAL, Scopus, and MEDLINE according to PRISMA guidelines. A random effect meta-analysis was carried out to evaluate the pooled effect size associated with diabetes mellitus on the outcome of infectious complications, duration of hospital stay and mortality in patients with burns. RESULTS: From a total of 1,397 studies, 13 eligible studies with 16,538 patients (3415F, 8361M) with burns were included in the analysis. Among these patients, 1702 patients had diabetes, and 14,836 patients were reported to be non-diabetic. A random effect meta-analysis revealed small-to-large size positive effect of diabetes on the infectious outcome (Hedge's g: 0.2, 95% CI: -0.03 to 0.44), overall mortality (0.16, -0.06 to 0.39), and duration of hospital stay (0.98, 0.50 to 1.45) in patients with burns. CONCLUSIONS: The present systematic review and meta-analysis provides evidence regarding the high morbidity and mortality related outcomes for diabetic patients with burns. The present study confirms the findings of a previously published systematic review suggesting diabetes to be an important and independent risk factor delineating the prognostic outcome of burns.

[Clinical value of carbon nanoparticles tracer in gastric cancer surgery to increase the number of lymph nodes retrieval].

Objective: To investigate the clinical value of carbon nanoparticles zonal tracer technique in lymph node retrieval of gastric cancer (GC). Methods: A retrospective cohort study was carried out. Clinicopathological data of GC patients who underwent radical D2 resection with carbon nanoparticles tracer in The First Affiliated Hospital of Hainan Medical University and Hainan Cancer Hospital from December 2015 and February 2019 were collected. Those with postoperative pathology of T1-2, Borrmann IV type GC, distant metastasis, preoperative neoadjuvant chemotherapy and incomplete data were excluded. A total of 181 patients were enrolled in this study, including 113 cases from the First Affiliated Hospital of Hainan Medical University and 68 cases from Hainan Cancer Hospital. Patients were categorized into two groups based on the methods of carbon nanoparticles tracer: zonal tracer group and traditional tracer group. In the traditional tracer group, 0.1-0.3 ml of carbon nanoparticle was injected subserously at the upper, lower, left and right 4 injection points 0.5 cm away from the edge of the tumor in the normal serous membrane. In the zonal tracer group, on the basis of the traditional tracer group, 0.1-0.3 ml of carbon nanoparticle was injected subserously at the first branch of the suprapyloric right gastric artery into the stomach, the first branch of the subpyloric right gastroepiploic artery into the stomach, the first branch of the minor curvature left gastric artery into the stomach and the first branch of the greater curvature left gastroepiploic artery into the stomach, respectively. The display of lymphatic vessels in each location and lymph nodes in each group by the tracing method was observed. The number of black-stained lymph nodes, the black staining rate of lymph nodes, the total number of detected lymph nodes, the total number of positive lymph nodes, and the metastatic rate of lymph node were compared between the two groups. Results: Eighty-nine patients were assigned to zonal tracer group, and 92 patients to traditional tracer group. There were no significant differences in baseline information between the two groups (all P>0.05). The median number of black-stained lymph nodes (median: 25.0 vs. 13.5, Z=-7.158, P<0.001) and the black staining rate of lymph nodes [(70.8±12.0)% vs. (47.1±15.7)%, t=11.399, P<0.001) in the zonal tracer group were significantly higher than those in the traditional tracer group. The total detected number of lymph nodes (37.5±11.5 vs. 29.6±11.8, t=4.581, P<0.001) and the total number of negative lymph nodes (31.3±12.5 vs. 24.9±11.1, t=3.621, P<0.001) were significantly higher in the zonal tracer group than those in the traditional tracer group. There were no significant differences in the total number of positive lymph nodes (median: 4.0 vs. 3.0, Z=-1.485, P=0.137), lymph node metastatic rate [78.7% (70/89) vs. 72.8% (67/92), χ(2)=0.834, P=0.361] and metastatic degree [median: 11% vs. 10%, Z=-0.483, P=0.629] between the two groups. Conclusion: The carbon nanoparticles zonal tracer method can increase the black-staining rate of lymph nodes and the detected number of lymph nodes, thus improving the accuracy of gastric cancer staging.

[Clinical features of 2019 novel coronavirus pneumonia in the early stage from a fever clinic in Beijing].

Objective: To summarize and analyze the clinical and imaging characteristics of patients with 2019 novel coronavirus pneumonia in the early stage in Beijing. Methods: A retrospective analysis of clinical and imaging data of 9 patients with 2019 novel coronavirus infection diagnosed in one fever clinicic in Beijing from January 18, 2020 to February 3, 2020. Results: 5 male and 4 female was included in those 9 patients, whose median age was 36 years, and the age range from 15 to 49 years. 8 of these patients had no underlying disease and one suffered from diabetes. 7 patients had a history of travel to Wuhan City or Hubei Province, and one patient was a medical staff. Two family clustered was found. The incubation period was 1 to 6 days. The clinical manifestations were fever in 8 cases (8/9) , dry cough in 5 cases (5/9) , pharyngalgia in 4 cases (4/9) , fatigue in 4 cases (4/9) , body soreness in 4 cases (4/9) , and blocked or watery nose in 1 case (1/9) . Six patients (6/9) had abnormal cell peripheral blood, of which 3 (3/9) had an increased monocyte count, 2 (2/9) had a reduced lymphocyte, and 1 (1/9) had an increased leukocyte count, while the 3 patients had normal cell blood routines. The median of CRP was 16.3 mg/L, including 5 patients with slightly elevated (5/9) , 4 patients with normal values (4/9) . the results of procalcitonin test were negative in5 patients. Three patients were examined by chest X-ray examination, one of which was normal, one case showed infiltrates of right upper lung, and another showed in right lower lung. All patients underwent chest HRCT. And 7 cases (7/9) showed multiple ground glass exudation, including 5 cases (5/7) involved bilateral lungs, 2 cases (2/7) involved unilateral lung, 3 cases (3/7) with patchy consolidation, and 2 cases (2/9) showed no abnormality. Conclusions: The patents with 2019 novel coronavirus pneumonia in this study generally have an epidemiological history. The clinical manifestations are fever and cough. Peripheral white blood cell counts were most normal And PCT were all negative. Chest HRCT manifested as multiple ground-glass opacities with partly consolidation. Some patients had normal chest radiographs but HRCT showed pneumonia. Some patients had no pneumonia on chest HRCT.

[Clinical features of 2019 novel coronavirus pneumonia in the early stage from a fever clinic in Beijing].

Objective: To summarize and analyze the clinical and imaging characteristics of patients with 2019 novel coronavirus pneumonia in the early stage in Beijing. Methods: A retrospective analysis of clinical and imaging data of 9 patients with 2019 novel coronavirus infection diagnosed in one fever clinicic in Beijing from January 18, 2020 to February 3, 2020. Results: 5 male and 4 female was included in those 9 patients, whose median age was 36 years, and the age range from 15 to 49 years. 8 of these patients had no underlying disease and one suffered from diabetes. 7 patients had a history of travel to Wuhan City or Hubei Province, and one patient was a medical staff. Two family clustered was found. The incubation period was 1 to 6 days. The clinical manifestations were fever in 8 cases (8/9) , dry cough in 5 cases (5/9) , pharyngalgia in 4 cases (4/9) , fatigue in 4 cases (4/9) , body soreness in 4 cases (4/9) , and blocked or watery nose in 1 case (1/9) . Six patients (6/9) had abnormal cell peripheral blood, of which 3 (3/9) had an increased monocyte count, 2 (2/9) had a reduced lymphocyte , and 1 (1/9) had an increased leukocyte count, while the 3 patients had normal cell blood routines. The median of CRP was 16.3 mg/L, including 5 patients with slightly elevated (5/9) , 4 patients with normal values (4/9) . the results of procalcitonin test were negative in5 patients. Three patients were examined by chest X-ray examination, one of which was normal, one case showed infiltrates of right upper lung, and another showed in right lower lung. All patients underwent chest HRCT. And 7 cases (7/9) showed multiple ground glass exudation, including 5 cases (5/7) involved bilateral lungs, 2 cases (2/7) involved unilateral lung, 3 cases (3/7) with patchy consolidation, and 2 cases (2/9) showed no abnormality. Conclusions: The patents with 2019 novel coronavirus pneumonia in this study generally have an epidemiological history. The clinical manifestations are fever and cough. Peripheral white blood cell counts were most normal And PCT were all negative. Chest HRCT manifested as multiple ground-glass opacities with partly consolidation. Some patients had normal chest radiographs but HRCT showed pneumonia. Some patients had no pneumonia on chest HRCT.

[Effect of silica dust on protein oxidative injury in lung tissue of mice].

Objective: To investigate the effect of silica dust on protein oxidative injury in the lung tissue of mice. Methods: A total of 60 mice were randomly divided into control group (not exposed to dust) , 2-hour group (inhalation of dust for 2 hours per day) , 4-hour group (inhalation of dust for 4 hours per day) , and 8-hour group (inhalation of dust for 8 hours per day) , with 15 mice in each group. During dust exposure, the mice were placed in a dust exposure cabinet; the dust was blown with an air blower and the concentration was maintained at 125 mg/m(3). All mice were exposed to silica dust for 3 weeks. The changes of the lung were observed after dust exposure ended, and spectrophotometry was performed to measure the activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) and protein carbonyl in the lung tissue. Results: The 2-, 4-, and 8-hour groups had marked edema, sporadic punctate hemorrhage, and nodular shadow in the lungs. Compared with the control group, the 2-, 4-, and 8-hour groups had a significant increase in lung coefficient (7.03±0.78 mg/g, 8.48±0.93 mg/g, and 8.99±0.85 mg/g vs 5.52±0.81 mg/g, P<0.05) . Compared with the control group, the 2-, 4-, and 8-hour groups had significant increases in the content of MDA (2.83±0.52, 3.94±0.65, and 4.56±0.77 nmol/mg prot vs 1.26±0.36 nmol/mg prot, P<0.05) and protein carbonyl (1.61±0.44, 1.96±0.47, and 2.20±0.58 nmol/mg prot vs 1.13±0.21 nmol/mg prot, P<0.05) in lung tissue. The 4- and 8-hour groups had a significantly lower activity of SOD than the control group (153.69±20.58 and 140.35±18.97 U/mg prot vs 186.00±25.46 U/mg prot, P<0.05) . Conclusions: Silica dust may lead to protein oxidative injury in the lung tissue of mice, which might play an important role in lung injury.

Slater Insulator in Iridate Perovskites with Strong Spin-Orbit Coupling.

The perovskite SrIrO_{3} is an exotic narrow-band metal owing to a confluence of the strengths of the spin-orbit coupling (SOC) and the electron-electron correlations. It has been proposed that topological and magnetic insulating phases can be achieved by tuning the SOC, Hubbard interactions, and/or lattice symmetry. Here, we report that the substitution of nonmagnetic, isovalent Sn^{4+} for Ir^{4+} in the SrIr_{1-x}Sn_{x}O_{3} perovskites synthesized under high pressure leads to a metal-insulator transition to an antiferromagnetic (AF) phase at T_{N}≥225 K. The continuous change of the cell volume as detected by x-ray diffraction and the λ-shape transition of the specific heat on cooling through T_{N} demonstrate that the metal-insulator transition is of second order. Neutron powder diffraction results indicate that the Sn substitution enlarges an octahedral-site distortion that reduces the SOC relative to the spin-spin exchange interaction and results in the type-G AF spin ordering below T_{N}. Measurement of high-temperature magnetic susceptibility shows the evolution of magnetic coupling in the paramagnetic phase typical of weak itinerant-electron magnetism in the Sn-substituted samples. A reduced structural symmetry in the magnetically ordered phase leads to an electron gap opening at the Brillouin zone boundary below T_{N} in the same way as proposed by Slater.

Relative bioavailability study of a new medium/long-chain triglyceride emulsion of propofol in beagle dogs.

The aim of this study was to evaluate the bioequivalence of a new generic formulation of propofol medium/long-chain triglyceride emulsion (test) and the available branded formulation (reference) to comply with regulatory criteria for marketing of the test product in China. This single-dose, randomized-sequence, open-label, 2-period crossover study was conducted in 6 beagle dogs. Blood samples were collected before dosing and at different time after dosing. Plasma samples were separated and assayed for propofol using a selective and sensitive HPLC method with fluorescence detection. The pharmacokinetic parameters AUC0-T, AUC0-∞, MRT, t1/2 and CL were determined from plasma concentration-time profile of both formulations. The formulations were considered bioequivalent when the 90% CIs of the geometric mean ratios (test:reference) for AUC0-T and AUC0-∞ were within the regulatory range of 80% to 125%.

An X-ray Raman spectrometer for EXAFS studies on minerals: bent Laue spectrometer with 20 keV X-rays.

An X-ray Raman spectrometer for studies of local structures in minerals is discussed. Contrary to widely adopted back-scattering spectrometers using ≤10 keV X-rays, a spectrometer utilizing ~20 keV X-rays and a bent Laue analyzer is proposed. The 20 keV photons penetrate mineral samples much more deeply than 10 keV photons, so that high intensity is obtained owing to an enhancement of the scattering volume. Furthermore, a bent Laue analyzer provides a wide band-pass and a high reflectivity, leading to a much enhanced integrated intensity. A prototype spectrometer has been constructed and performance tests carried out. The oxygen K-edge in SiO(2) glass and crystal (α-quartz) has been measured with energy resolutions of 4 eV (EXAFS mode) and 1.3 eV (XANES mode). Unlike methods previously adopted, it is proposed to determine the pre-edge curve based on a theoretical Compton profile and a Monte Carlo multiple-scattering simulation before extracting EXAFS features. It is shown that the obtained EXAFS features are reproduced fairly well by a cluster model with a minimal set of fitting parameters. The spectrometer and the data processing proposed here are readily applicable to high-pressure studies.

Determining the in-plane orientation of the ground-state orbital of CeCu2Si2.

We have successfully determined the hitherto unknown sign of the B(4)(4) Stevens crystal-field parameter of the tetragonal heavy-fermion compound CeCu(2)Si(2) using vector q-dependent nonresonant inelastic x-ray scattering experiments at the cerium N(4,5) edge. The observed difference between the two different directions, q∥[100] and q∥[110], is due to the anisotropy of the crystal-field ground state in the (001) plane and is observable only because of the utilization of higher than dipole transitions possible in nonresonant inelastic x-ray scattering. This approach allows us to go beyond the specific limitations of dc magnetic susceptibility, inelastic neutron scattering, and soft x-ray spectroscopy, and provides us with a reliable information about the orbital state of the 4f electrons relevant for the quantitative modeling of the quasiparticles and their interactions in heavy-fermion systems.

Multiple-wave diffraction in high energy resolution back-reflecting x-ray optics.

We have studied the effects of multiple-wave diffraction in a novel optical scheme recently published by Shvyd'ko et al. utilizing Bragg diffraction of x rays in backscattering geometry from asymmetrically cut crystals for achieving energy resolutions beyond the intrinsic width of the Bragg reflection. By numerical simulations based on dynamic x-ray diffraction and by experimentation involving two-dimensional angular scans of the back-reflecting crystal, multiple-wave diffraction was found to contribute up to several tens percent loss of efficiency but can be avoided without degrading the energy resolution of the original scheme by careful choice of azimuthal orientation of the diffracting crystal surface and by tilting of the crystal perpendicular to the dispersion plane.

Structural and microscopic relaxations in glycerol: an inelastic x-ray scattering study.

The THz dynamics of liquid glycerol has been probed by inelastic x-ray scattering at different pressure spanning the 0.66-3 Kbar range. A comparison with ultrasound absorption results available in literature leads us to identify the presence of two different relaxations, a structural (slow) relaxation and a microscopic (fast) one. Although the former has been already thoroughly studied in glycerol by lower frequency spectroscopic techniques, no hints on the latter are so far available in literature. We observe that the characteristic timescale of this fast relaxation ranges in the sub-picosecond, tends to decrease with increasing the wave-vector and seems rather insensitive to pressure changes. Finally, the timescale and strength of the fast relaxation have a direct link revealing the microscopic, single particle, nature of the involved process.

Cellular immunologic response to primary cryoablation of C6 gliomas in rats.

The immunological consequences of cryoablation for gliomas are largely unknown. cryoablation is an attractive therapeutic option for tumors due to its minimally invasive nature. cryoablation is also potentially immunogenic. With an aim to explore changes in cellular immunity following argon-helium cryosurgery, we established Wistar rat models bearing subcutaneous C6 glioma and divided the rats into the normal control (30 rats), sham-operated (33 rats), surgical resection (30 rats), and cryosurgery (33 rats) groups with corresponding treatments. The tumor cell morphology was observed, and changes in the T lymphocyte subset and NK lymphocyte subset and the ratio of Th1/Th2 were assessed with flow cytometry following the cryosurgery. The results showed that subcutaneous tumor implantation was successful in all cases and this was confirmed histologically. Compared with surgical resection that caused significant reduction in CD3(+), CD4(+), CD14(+), CD16+56 cell percentages, cryosurgery resulted in significantly increased percentages of CD3(+), CD4(+), CD14(+), CD16+56 cells (P < 0.05) with a increase of the Th1/Th2 ratio 7 days after the operation. These results demonstrate that in addition to tumor cell destruction, cryosurgery also results in enhanced cellular immunity, suggesting the great potential of argon-helium cryosurgery in clinical management of gliomas.

Susceptibility-weighted imaging in the diagnosis of early basal ganglia germinoma.

BACKGROUND AND PURPOSE: Germinomas originating from the basal ganglia (BG) are rare. Early diagnosis is important for favorable prognosis, but it is difficult due to the slow clinical course and subtle changes on neuroimaging. The purpose of this study was to evaluate the usefulness of susceptibility-weighted imaging (SWI) in the diagnosis of early BG germinoma. MATERIALS AND METHODS: From 2006 to 2008, 6 BG germinomas were diagnosed in children at our institution by pathology. Conventional MR imaging and SWI were available in all cases. Clinical, neuroradiologic, and follow-up features were retrospectively studied. RESULTS: Three cases were classified as early BG germinomas. Conventional MR imaging demonstrated that the tumor size was <10 mm in the largest diameter. The tumors were invisible or showed slight hyperintensity on T1-weighted images (T1WI) and patchy slight hyperintensity on T2-weighted images (T2WI) without mass effect or enhancement. On SWI, the tumors appeared as obvious hypointensity in the globus pallidus and putamen, and the size was larger than that on conventional T1WI and T2WI. The other 3 cases with tumor size >10 mm in largest diameter were classified as late BG germinomas, with tumor necrosis, fluid-fluid levels, and perifocal edema, including 1 case with subependymal spread. On SWI, only the solid portion of the tumors showed hypointensity. No recurrence was noted on follow-up. CONCLUSIONS: SWI appears to be more sensitive in detecting early BG germinomas than conventional MR imaging. This capability may prove to be useful in future attempts to characterize early BG germinomas.

Signaling mechanisms mediating muscarinic enhancement of GABAergic synaptic transmission in the spinal cord.

Activation of muscarinic acetylcholine receptors (mAChRs) inhibits spinal nociceptive transmission by potentiation of GABAergic tone through M(2), M(3), and M(4) subtypes. To study the signaling mechanisms involved in this unique mAChR action, GABAergic spontaneous inhibitory postsynaptic currents (sIPSCs) of lamina II neurons were recorded using whole-cell patch clamp techniques in rat spinal cord slices. The mAChR agonist oxotremorine-M caused a profound increase in the frequency of GABAergic sIPSCs, which was abolished in the Ca(2+)-free solution. Inhibition of voltage-gated Ca(2+) channels with Cd(2+) and Ni(2+) largely reduced the effect of oxotremorine-M on sIPSCs. Blocking nonselective cation channels (NSCCs) with SKF96365 or 2-APB also largely attenuated the effect of oxotremorine-M. However, the KCNQ channel blocker XE991 and the adenylyl cyclase inhibitor MDL12330A had no significant effect on oxotremorine-M-induced increases in sIPSCs. Furthermore, the phosphoinositide-3-kinase (PI3K) inhibitor wortmannin or LY294002 significantly reduced the potentiating effect of oxotremorine-M on sIPSCs. In the spinal cord in which the M(3) subtype was specifically knocked down by intrathecal small interfering RNA (siRNA) treatment, SKF96365 and wortmannin still significantly attenuated the effect of oxotremorine-M. In contrast, SKF96365 and wortmannin both failed to alter the effect of oxotremorine-M on sIPSCs when the M(2)/M(4) mAChRs were blocked. Therefore, our study provides new evidence that activation of mAChRs increases synaptic GABA release through Ca(2+) influx and voltage-gated Ca(2+) channels. The PI3K-NSCC signaling cascade is primarily involved in the excitation of GABAergic interneurons by the M(2)/M(4) mAChRs in the spinal dorsal horn.

Pressure-induced valence anomaly in TmTe probed by resonant inelastic X-ray scattering.

The pressure-induced valence transition in TmTe was investigated by resonant inelastic x-ray scattering at the Tm L3 edge, a powerful probe of the rare-earth valent state. The data are analyzed within the Anderson impurity model which yields key parameters such as the Tm 4f-5d hybridization. In addition to the general tendency of the f electrons towards delocalization, we find a plateau in both the Tm valence and hybridization pressure dependences between 4.3 and 6.5 GPa which is interpreted in terms of an n-channel Kondo (NCK) screening process. This behavior is at odds with the usually continuous, single-channel Kondo-like f delocalization while being supported by the seminal calculations of the NCK temperature in Tm ion by Saso et al. Our study raises the interesting possibility that an NCK effect realized in a compressed mixed-valent f system could impede the concomitant electron delocalization.

Anomalous angular dependence of the dynamic structure factor near Bragg reflections: graphite.

The electron energy-loss function of graphite is studied for momentum transfers q beyond the first Brillouin zone. We find that near Bragg reflections the spectra can change drastically for very small variations in q. The effect is investigated by means of first principle calculations in the random phase approximation and confirmed by inelastic x-ray scattering measurements of the dynamic structure factor S(q, omega). We demonstrate that this effect is governed by crystal local field effects and the stacking of graphite. It is traced back to a strong coupling between excitations at small and large momentum transfers.