Comparison of EBSD patterns simulated by two multislice methods.

The extraction of crystallography information from electron backscatter diffraction (EBSD) patterns can be facilitated by diffraction simulations based on the dynamical electron diffraction theory. In this work, the EBSD patterns are successfully simulated by two multislice methods, that is, the real space (RS) method and the revised real space (RRS) method. The calculation results by the two multislice methods are compared and analyzed in detail with respect to different accelerating voltages, Debye-Waller factors and aperture radii. It is found that the RRS method provides a larger view field of the EBSD patterns than that by the RS method under the same calculation conditions. Moreover, the Kikuchi bands of the EBSD patterns obtained by the RRS method have a better match with the experimental patterns than those by the RS method. Especially, the lattice parameters obtained by the RRS method are more accurate than those by the RS method. These results demonstrate that the RRS method is more accurate for simulating the EBSD patterns than the RS method within the accepted computation time.

Quantitative candidate gene association studies of metabolic traits in Han Chinese type 2 diabetes patients.

Recent genome-wide association studies have identified many loci associated with type 2 diabetes mellitus (T2DM), hyperuricemia, and obesity in various ethnic populations. However, quantitative traits have been less well investigated in Han Chinese T2DM populations. We investigated the association between candidate gene single nucleotide polymorphisms (SNPs) and metabolic syndrome-related quantitative traits in Han Chinese T2DM subjects. Unrelated Han Chinese T2DM patients (1975) were recruited. Eighty-six SNPs were genotyped and tested for association with quantitative traits including lipid profiles, blood pressure, body mass index (BMI), serum uric acid (SUA), glycated hemoglobin (HbA1c), plasma glucose [fasting plasma glucose (FPG)], plasma glucose 120 min post-OGTT (P2PG; OGTT = oral glucose tolerance test), and insulin resistance-related traits. We found that CAMTA1, ABI2, VHL, KAT2B, PKHD1, ESR1, TOX, SLC30A8, SFI1, and MYH9 polymorphisms were associated with HbA1c, FPG, and/or P2PG; GCK, HHEX, TCF7L2, KCNQ1, and TBX5 polymorphisms were associated with insulin resistance-related traits; ABCG2, SLC2A9, and PKHD1 polymorphisms were associated with SUA; CAMTA1, VHL, KAT2B, PON1, NUB1, SLITRK5, SMAD3, FTO, FANCA, and PCSK2 polymorphisms were associated with blood lipid traits; CAMTA1, SPAG16, TOX, KCNQ1, ACACB, and MYH9 polymorphisms were associated with blood pressure; and UBE2E3, SPAG16, SLC2A9, CDKAL1, CDKN2A/B, TCF7L2, SMAD3, and PNPLA3 polymorphisms were associated with BMI (all P values <0.05). Some of the candidate genes were associated with metabolic and anthropometric traits in T2DM in Han Chinese. Although none of these associations reached genome-wide significance (P < 5 x 10(-8)), genes and loci identified in this study are worthy of further replication and investigation.

Dynamical electron diffraction simulation for non-orthogonal crystal system by a revised real space method.

In the transmission electron microscopy, a revised real space (RRS) method has been confirmed to be a more accurate dynamical electron diffraction simulation method for low-energy electron diffraction than the conventional multislice method (CMS). However, the RRS method can be only used to calculate the dynamical electron diffraction of orthogonal crystal system. In this work, the expression of the RRS method for non-orthogonal crystal system is derived. By taking Na2 Ti3 O7 and Si as examples, the correctness of the derived RRS formula for non-orthogonal crystal system is confirmed by testing the coincidence of numerical results of both sides of Schrödinger equation; moreover, the difference between the RRS method and the CMS for non-orthogonal crystal system is compared at the accelerating voltage range from 40 to 10 kV. Our results show that the CMS method is almost the same as the RRS method for the accelerating voltage above 40 kV. However, when the accelerating voltage is further lowered to 20 kV or below, the CMS method introduces significant errors, not only for the higher-order Laue zone diffractions, but also for zero-order Laue zone. These indicate that the RRS method for non-orthogonal crystal system is necessary to be used for more accurate dynamical simulation when the accelerating voltage is low. Furthermore, the reason for the increase of differences between those diffraction patterns calculated by the RRS method and the CMS method with the decrease of the accelerating voltage is discussed.

Han Chinese patients with dopa-responsive dystonia exhibit a low frequency of exonic deletion in the GCH1 gene.

We identified three novel mutations of the GTP cyclohydrolase 1 (GCH1) gene in patients with familial dopa-responsive dystonia (DRD), but were unable to identify meaningful sporadic mutations in patients with no obvious family DRD background. To investigate whether GCH1 regional deletions account for the etiology of DRD, we screened for heterozygous exonic deletions in DRD families and in patients with sporadic DRD. Multiple ligation-dependent probe amplification analysis and quantitative real-time polymerase chain reaction amplification was performed in all members of our DRD cohort and in controls to detect exonic deletions in GCH1, tyrosine hydroxylase, and the epsilon-sarcoglycan-encoding (SGCE) genes. Using these techniques, we detected a GCH1 exon 1 heterozygous deletion in 1 of 10 patients with sporadic DRD. Therefore, we concluded that exonic deletion in the GCH1 gene only accounted for the etiology in a small percentage of patients with sporadic DRD in our Han Chinese cohort.

MYH9 gene polymorphisms may be associated with cerebrovascular blood flow in patients with type 2 diabetes.

Genetic factors play an important role in type 2 diabetes (T2D) complications. Alteration of cerebrovascular blood flow (CBF) is a direct result of cerebrovascular diseases. However, few studies have reported the role of genetics on CBF in patients with T2D. We investigated whether single-nucleotide polymorphisms (SNPs) in metabolic disease genes are associated with CBF in patients with T2D. CBF velocities of CBF were measured in 337 Han Chinese patients with T2D using transcranial Doppler sonography, with 54 cerebrovascular blood flow parameters documented. Fifty-two SNPs from 31 metabolic disease candidate genes were genotyped in patients. Quantitative allelic association and haplotype analyses were performed for candidate gene SNPs and CBF phenotypes. Spearman correlation was used to determine the relationship between CBF parameters and basic clinical characteristics, particularly, body mass index, lipids, fibrinogen, and GHbA1c. MYH9 gene SNPs (rs875726 and rs735853) may be associated with the peak velocity of the right-middle cerebral artery. SNPs rs875726, rs2009930, and rs375246 of the MYH9 gene may be associated with the mean velocity of the right-anterior and posterior cerebral artery. The haplotype G-C-A (rs2239782-rs3752462- rs2269532) of MYH9 may be associated with CBF. MYH9 gene polymorphisms may be associated with multiple CBF phenotypes in Chinese patients with T2D. However, whether MYH9 is a candidate gene for cerebrovascular diseases in Chinese patients with T2D remains unknown.

Expression and clinical value of peroxiredoxin-1 in patients with pancreatic cancer.

BACKGROUND: Peroxiredoxin-1 (Prx-1) is an important protector for redox damage and its abnormal expression is continually reported in various tumors. This study aims to investigate the expression status of Prx-1 and evaluate its clinical value in pancreatic cancer. METHODOLOGY: Immunohistochemistry was used to detect Prx-1 expression in pancreatic cancer tissues and para-cancerous tissues. Enzyme-linked immunosorbent assay (ELISA) method was applied to detect the serum Prx-1 levels. RESULTS: The immunohistochemical results indicated that positive rate of Prx-1 was (p < 0.05) higher in pancreatic cancer tissues (74.4%) than in para-cancerous tissues (37.2%). Prx-1 expression was positively correlated with vascular endothelial growth factor (VEGF) and microvessel density (MVD) in cancer tissues. The ELISA results showed that patients with pancreatic cancer had a higher serum Prx-1 level than healthy subjects (31.2 ± 13.5 vs. 13.2 ± 11.9 ng/ml, p < 0.001). Prx-1 expression was correlated with aggressive clinicopathological parameter. The combination of serum Prx-1 and CA19-9, the area under the curve (AUC) was significantly higher than Prx-1 separate. Positive Prx-1 expression was correlated with disappointing overall survival (OS) (p = 0.002) and disease-free survival (DFS) (p < 0.001). Multivariate analysis showed that Prx-1 staining as an independent biomarker of poor OS (p = 0.035) and DFS (p < 0.001). CONCLUSION: These findings suggest that the levels of Prx-1 expression are significantly increased in pancreatic cancer. The up-regulated Prx-1 is closely related to tumor angiogenesis and acts as a promising tumor marker for diagnosis and prognosis of pancreatic cancer.

A novel splicing site mutation of the GPR143 gene in a Chinese X-linked ocular albinism pedigree.

Ocular albinism is an X-linked inherited disease characterized by hypopigmentation of the iris and nystagmus. To identify a new disease-causing mutation of ocular albinism, we collected a Han Chinese pedigree with 7 male congenital nystagmus patients over 3 generations. Slit-lamp photography and optical coherence tomography were performed for the proband. Genomic DNA was extracted from a whole blood sample from the proband using the high-salt method. Polymerase chain reaction (PCR) sequencing was carried out for GPR143 and FRMD7 genes. The three-dimensional structures of the wild-type and mutant GPR143 proteins were determined using SWISS-MODEL. The transmission of the disease in the pedigree clearly followed an X-linked pattern. The proband had significant iris and fundus hypopigmentation. Optical coherence tomography showed severe foveal hypoplasias in both eyes of the proband. A novel splicing site (G/C) mutation was found on the boundary of the 6th intron and the 7th exon of the GPR143 gene, resulting in a 9-amino-acid deletion (codons 257-265) in the 6th transmembrane domain of the GPR143 protein. In conclusion, a novel splicing site mutation of the GPR143 gene was found in a Han Chinese congenital ocular albinism pedigree.

Recoil effects of a motional scatterer on single-photon scattering in one dimension.

The scattering of a single photon with sufficiently high energy can cause a recoil of a motional scatterer. We study its backaction on the photon's coherent transport in one dimension by modeling the motional scatterer as a two-level system, which is trapped in a harmonic potential. While the reflection spectrum is of a single peak in the Lamb-Dicke limit, multi-peaks due to phonon excitations can be observed in the reflection spectrum as the trap becomes looser or the mass of the two-level system becomes smaller.

Residue depletion of decoquinate in chicken tissues after oral administration.

A rapid, sensitive, and reliable high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed and validated for the analysis of decoquinate in chicken tissues. The compounds were extracted using acetonitrile by liquid-liquid extraction (LLE) and purified with an Oasis(™) HLB solid-phase extraction (SPE) cartridge. Chromatographic separation was performed on an XTerra C18 reversed-phase column with a mobile phase of water containing 0.1% formic acid and acetonitrile. The analyte was detected by tandem quadrupole mass spectrometry after positive electrospray ionization by multiple reaction monitoring. The detection and quantitation limits were 1 and 2.5 µg/kg, respectively. The recoveries of edible tissues ranged from 85.3% to 104.9%, with relative standard deviations (RSD) lower than 10.4%. The depletion profile of decoquinate was studied in healthy chickens after oral administration of feed containing 27.2 mg/kg decoquinate for 10 consecutive days. The residue concentrations of decoquinate in chicken muscle and liver were detected using the developed method. The highest residue concentrations were attained 0.25 day post-treatment, and decoquinate residues were still detected 5 days postmedication in the tissues examined. The developed method has been successfully applied to the depletion study of decoquinate in chicken tissues. The recommended withdrawal period with oral administration based on our research is 3 days.

Multiparticle quantum Szilard engine with optimal cycles assisted by a Maxwell's demon.

We present a complete-quantum description of a multiparticle Szilard engine that consists of a working substance and a Maxwell's demon. The demon is modeled as a multilevel quantum system with specific quantum control, and the working substance consists of identical particles obeying Bose-Einstein or Fermi-Dirac statistics. In this description, a reversible scheme to erase the demon's memory by a lower-temperature heat bath is used. We demonstrate that (1) the quantum control of the demon can be optimized for a single-particle Szilard engine so that the efficiency of the demon-assisted thermodynamic cycle could reach the Carnot cycle's efficiency and (2) the low-temperature behavior of the working substance is very sensitive to the quantum statistics of the particles and the insertion position of the partition.

Quantum Maxwell's demon in thermodynamic cycles.

We study the physical mechanism of Maxwell's demon (MD), which helps do extra work in thermodynamic cycles with the heat engine. This is exemplified with one molecule confined in an infinitely deep square potential with a movable solid wall. The MD is modeled as a two-level system (TLS) for measuring and controlling the motion of the molecule. The processes in the cycle are described in a quantum fashion. It is discovered that a MD with quantum coherence or one at a temperature lower than the molecule's heat bath can enhance the ability of the whole working substance, formed by the heat engine plus the MD, to do work outside. This observation reveals that the essential role of the MD is to drive the whole working substance off equilibrium, or equivalently, to work between two heat baths with different effective temperatures. The elaborate studies with this model explicitly reveal the effect of finite size off the classical limit or thermodynamic limit, which contradicts common sense on a Szilard heat engine (SHE). The quantum SHE's efficiency is evaluated in detail to prove the validity of the second law of thermodynamics.

Exuberant transverse ligament degeneration causing high cervical myelopathy.

Two patients with cervical myelopathy and C1-C2 retro-odontoid masses were examined. Preoperative magnetic resonance imaging studies suggested soft tissue pannus, as might be seen in rheumatoid arthritis; however, the results of serologic testing for rheumatoid factor were negative in both patients. Intraoperative findings and pathologic examination revealed degenerative fibrocartilage without inflammation or neoplasia. Similar lesions reported in the literature have been described as retro-odontoid disk hernia, damaged transverse ligaments, transverse ligament degeneration, synovial cysts, ganglion cysts, and degenerative articular cysts. These lesions may share a common pathophysiologic origin and represent a single disease process, namely exuberant degeneration of the transverse ligament.

Surgery for cervical spinal cord compression in patients with multiple sclerosis.

OBJECTIVE: The goal of this study was to investigate the clinical and paraclinical features, treatment, and outcomes of patients with multiple sclerosis (MS) and coexisting spinal cord compression secondary to either cervical spondylosis or cervical disc disease. Patients with MS commonly experience neurological disabilities that present as myelopathy associated with bladder dysfunction. For some patients with MS, however, this neurological deterioration may result from coexisting spinal cord compression attributable to either spondylosis or a herniated disc. Overlapping symptoms of the two conditions do not allow clear clinical determination of the underlying cause of worsening. METHODS: Patients with MS who underwent cervical decompression surgery were selected. Medical records were retrospectively reviewed, to collect data on their pre- and postoperative clinical courses. RESULTS: Nine women and five men with definite MS were selected for cervical decompression surgery to treat neurological deterioration considered to be at least partially attributable to spinal cord compression. The most common symptoms were progressive myelopathy (n = 13), neck pain (n = 11), and cervical radiculopathy (n = 10). Bladder dysfunction was notably absent among these patients with MS with moderate disabilities. Surgical intervention was frequently delayed because the neurological deterioration was initially thought to be attributable to MS. The majority of patients experienced either improvement or stabilization of their preoperative symptoms in the immediate postoperative period; three subjects (21%) maintained this improvement after a mean follow-up period of 3.8 years. No MS relapses, permanent neurological worsening, or serious complications resulting from surgery or general anesthesia were noted. CONCLUSION: Carefully selected patients with MS and cervical spinal cord compression secondary to either spondylosis or disc disease may benefit from surgical decompression, with minimal associated morbidity. Clinical features (especially neck pain and cervical radiculopathy) and magnetic resonance imaging may assist clinicians in differentiating between the two conditions and may guide appropriate treatment without undue delay.

[Synthesis of N-(4-carbomethoxy-4-phthalimidobutanoyl)-N-substituted glycines, proline and pyroglutamic acid].

This paper reports the synthesis of eleven N-(4-carbomethoxy-4-phthalimidobutanoyl)-N-substituted glycines (VII1-9), proline (VII10) and pyroglutamic acid (VII11) expected to have inhibitory activity on angiotensin converting enzyme. All of the compounds mentioned above and the corresponding t-butyl esters of VII1-9 were not reported in the literature previously. The structures were confirmed through their IR, 1HNMR, MS spectra and elemental analysis. In preliminary test in rats, compounds VII8, VII9 and VII10 showed marked hypotensive activity.

[Synthesis of N-(4-substituted amino-4-oxobutyryl)-N-substituted glycines].

Nine N-(4-substituted amino-4-oxobutyryl)-N-substituted glycines expected to have inhibitory activity on angiotensin-converting enzyme were synthesized. All of the title compounds and their t-butyl esters were unreported in the literature. In preliminary test in rats, compounds V2, V6 and V7 showed marked hypotensive activity.

[Synthesis of N-(4-carbethoxy-4-substituted butyryl)-N-substituted glycines].

This paper reports the synthesis of nine N-(4-carbethoxy-4-substituted butyryl)-N-substituted glycines and their corresponding t-butyl esters. The former were expected to have inhibitory activity of angiotensin-converting enzyme. All of the compounds mentioned above were unreported in the literature. In preliminary test in rats, compounds VII7 and VII9 showed marked hypotensive activity.