Tunable charge transfer properties in metal-phthalocyanine heterojunctions

Organic materials such as phthalocyanine-based systems present a great potential for organic device applications due to the possibility of integrating films of different organic materials to create organic heterostructures which combine the electrical capabilities of each material. This opens the possibility to precisely engineer and tune new electrical properties. In particular, similar transition metal phthalocyanines demonstrate hybridization and charge transfer properties which could lead to interesting physical phenomena. Although, when considering device dimensions, a better understanding and control of the tuning of the transport properties still remain in the focus of research. Here, by employing conductive atomic force microscopy techniques, we provide an insight about the nanoscale electrical properties and transport mechanisms of MnPc and fluorinated phthalocyanines such as F16CuPc and F16CoPc. We report a transition from typical diode-like transport mechanisms for pure MnPc thin films to space-charge-limited current transport regime (SCLC) for Pc-based heterostructures. The controlled addition of fluorinated phthalocyanine also provides highly uniform and symmetric-polarized transport characteristics with conductance enhancements up to two orders of magnitude depending on the polarization. We present a method to spatially map the mobility of the MnPc/F16CuPc structures with a nanoscale resolution and provide theoretical calculations to support our experimental findings. This well-controlled nanoscale tuning of the electrical properties for metal transition phthalocyanine junctions stands as key step for future phthalocyanine-based electronic devices, where the low dimension charge transfer, mediated by transition metal atoms could be intrinsically linked to a transfer of magnetic moment or spin.

PET/CT imaging in diagnosing lymph node metastasis of esophageal carcinoma and its comparison with pathological findings

OBJECTIVE

To investigate the usefulness of 18F-FDG PET/CT imaging in the diagnosis of lymph node metastasis of esophageal carcinoma and to compare its results with pathological findings.

PATIENTS AND METHODS

This study examined 43 cases of patients (32 males and 11 females, aged 54 ± 13 years old) being diagnosed with lymph node metastasis of esophageal carcinoma in our hospital between 2005 and 2014. All of these patients accepted 18F-FDG PET/CT imaging 10 days before the operation. Before reconstruction, each patient went through the body scan. PET/CT images were subject to comprehensive diagnostic analyses, by three experienced radiologists and/or professional nuclear physicians, on the number of metastatic lymph nodes and the maximum standardized uptake value (SUVmax). A control study was also performed on the pathological findings according to the latest esophageal cancer lymph node partition.

RESULTS

A total of 846 lymph nodes were taken out from the patients, among which 154 were confirmed with metastasis. When the SUVmax cutoff values were set at 2.5 and 5, 201 and 173 metastatic lymph nodes were found by 18F-FDG PET/CT imaging, respectively. Additionally, under such condition, 18F-FDG PET/CT imaging had the esophageal sensitivity of 69.48% vs 87.66%, specificity of 92.71% vs 94.51%, accuracy of 83.33% vs 93.26%, positive predictive value of 53.23% vs 78.03%, and negative predictive value of 92.71% vs 97.18%.

CONCLUSIONS

18F-FDG PET/CT had high accuracy in imaging lymph node metastasis of esophageal cancer. SUVmax cutoff value of 5 had a higher diagnostic accuracy and should be recommended in clinical practice.

HLA-B allele dropout in PCR sequence-specific oligonucleotide probe typing due to intronic polymorphism in the novel B*58:01:01:02 allele

Currently, Luminex technology based on the PCR sequence-specific oligonucleotide (SSO) probe method has been widely used for HLA genotyping in the immunogenetics laboratories. Here, we reported a case with HLA-B allele dropout by Luminex technology. The initial HLA-B result of the Luminex method with a commercial agent kit was inconclusive, and then, the result of PCR-SBT technology indicated the dropout as a HLA-B*58 allele. Subsequently, the full-length sequence of HLA-B allele was determined by TOPO-TA cloning, and a novel allele B*58:01:01:02 was identified in the individual. Compared with HLA-B*58:01:01:01, the novel allele showed some nucleotides difference at 509 C>T, 521 T>G and CCC insertion in position 503 of intron 2. According to the full-length sequence, the new mutations of intron 2 were contributed to HLA-B locus allele dropout in the sample. Our results indicated multiplatform should be used to improve the HLA typing accuracy when a conclusive HLA genotype cannot be determined.

HLA-A, -B and -DRB1 allele and haplotype frequencies of 8333 Chinese Han from the Zhejiang province, China

The distribution of human leucocyte antigen (HLA) allele and haplotype is varied among different ethnic populations. In this study, HLA-A, -B and -DRB1 allele and haplotype frequencies were determined in 8333 volunteer bone marrow donors of Zhejiang Han population using the polymerase chain reaction sequence-based typing. A total of 52 HLA-A, 96 HLA-B and 61 HLA-DRB1 alleles were found. Of these, the top three frequent alleles in HLA-A, HLA-B and HLA-DRB1 loci, respectively, were A*11:01 (24.53%), A*24:02 (17.35%), A*02:01 (11.58%); B*40:01 (15.67%), B*46:01 (11.87%), B*58:01 (9.05%); DRB1*09:01 (17.54%),DRB1*12:02 (9.64%) and DRB1*08:03 (8.65%). A total of 171 A-B-DRB1 haplotypes with a frequency of >0.1% were presented and the five most common haplotypes were A*33:03-B*58:01- DRB1*03:01, A*02:07-B*46:01-DRB1*09:01, A*30:01-B*13:02-DRB1*07:01, A*33:03-B*58:01-RB1*13:02 and A*11:01-B*15:02-DRB1*12:02. The information will be useful for selecting unrelated bone marrow donors and for anthropology studies and pharmacogenomics analysis.

Multicenter Prospective Trial of Stent Placement in Patients with Symptomatic High-Grade Intracranial Stenosis

BACKGROUND AND PURPOSE

On the basis of the high 1-month stroke and/or death (14.7%) rates associated with stent placement in the Stenting versus Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis trial, modifications in patient selection and procedural aspects for intracranial stent placement have been recommended. We performed a multicenter prospective single-arm trial to determine whether such modifications would result in lower rates of periprocedural stroke and/or death.

MATERIALS AND METHODS

The study enrolled patients with recent transient ischemic attack or ischemic stroke (excluding perforator ischemic events) related to high-grade (70%-99% in severity) stenosis of a major intracranial artery. Patients were treated by using angioplasty and self-expanding stents 3 weeks after the index ischemic event at 1 of the 10 high-volume centers in China. An independent neurologist ascertained the occurrence of any stroke and/or death within 1 month after the procedure.

RESULTS

A total of 100 consecutive patients were recruited. The target lesions were located in the middle cerebral artery (M1) (n = 38, 38%), intracranial internal carotid artery (n = 17, 17%), intradural vertebral artery (n = 18, 18%), and basilar artery (n = 27, 27%). The technical success rate of stent deployment with residual stenosis of <50% was 100%. The overall 1-month stroke and/or death rate was 2% (95% confidence interval, 0.2%-7.0%). Two ischemic strokes occurred in the pontine region (perforator distribution) in patients following angioplasty and stent placement for basilar artery stenosis.

CONCLUSIONS

The results of this prospective multicenter study demonstrated that modifications in patient selection and procedural aspects can substantially reduce the 1-month stroke and/or death rate following intracranial stent placement.

Assessment of biocompatibility of 3D printed photopolymers using zebrafish embryo toxicity assays

3D printing has emerged as a rapid and cost-efficient manufacturing technique to enable the fabrication of bespoke, complex prototypes. If the technology is to have a significant impact in biomedical applications, such as drug discovery and molecular diagnostics, the devices produced must be biologically compatible to enable their use with established reference assays and protocols. In this work we demonstrate that we can adapt the Fish Embryo Test (FET) as a new method to quantify the toxicity of 3D printed microfluidic devices. We assessed the biocompatibility of four commercially available 3D printing polymers (VisiJetCrystal EX200, Watershed 11122XC, Fototec SLA 7150 Clear and ABSplus P-430), through the observation of key developmental markers in the developing zebrafish embryos. Results show all of the photopolymers to be highly toxic to the embryos, resulting in fatality, although we do demonstrate that post-printing treatment of Fototec 7150 makes it suitable for zebrafish culture within the FET.

Pdcd4 deficiency enhances macrophage lipoautophagy and attenuates foam cell formation and atherosclerosis in mice

Macrophage foam cells, a major component of the atherosclerotic lesion, have vital roles in the development of atherosclerosis. Lipoautophagy, a type of autophagy characterized by selective delivery of lipid droplet for lysosomal degradation, may impact atherosclerosis by regulating macrophage foam cell formation. Previously, we reported that programmed cell death 4 (PDCD4), a tumor suppressor, negatively regulated autophagy in tumor cells. However, its roles in macrophage lipoautophagy, foam cell formation and atherosclerosis remain to be established. Here we found that Pdcd4 deficiency clearly improved oxidized low-density lipoproteins-impaired autophagy efflux, promoted autophagy-mediated lipid breakdown in murine macrophages and thus prevented macrophage conversion into foam cells. Importantly, Pdcd4 deficiency in mice significantly upregulated macrophage autophagy in local plaques along with attenuated lipid accumulation and atherosclerotic lesions in high-fat-fed Apolipoprotein E knockout mice. Bone marrow transplantation experiment demonstrated that PDCD4-mediated autophagy in hematopoietic cells contributed to the development of atherosclerosis. These results indicate that endogenous PDCD4 promotes for macrophage foam cell formation and atherosclerosis development via inhibiting autophagy and provides new insights into atherogenesis, suggesting that promoting macrophage autophagy through downregulating PDCD4 expression may be beneficial for treating atherosclerosis.

A mix of S and ΔS variants of STAT3 enable survival of activated B-cell-like diffuse large B-cell lymphoma cells in culture

Activated B-cell-like diffuse large B-cell lymphoma (ABC DLBCL) is characterized by increased expression and activator of signal transducer and activator of transcription 3 (STAT3). ABC DLBCL cells require STAT3 for growth in culture. In ABC DLBCL cells, eosinophils and perhaps all cells, four variant STAT3 mRNAs (Sα, ΔSα, Sβ and ΔSβ) are present as a result of two alternative splicing events, one that results in the inclusion of a 55-residue C-terminal transactivation domain (α) or a truncated C-terminal domain with 7 unique residues (β) and a second that includes (S) or excludes (ΔS) the codon for Ser-701 in the linker between the SH2 and C-terminal domains. A substantial literature indicates that both α and β variants are required for optimal STAT3 function, but nothing is known about functions of ΔS variants. We used a knockdown/re-expression strategy to explore whether survival of ABC DLBCL cells requires that the four variants be in an appropriate ratio. No single variant rescued survival as well as STAT3Sα-C, Sα with activating mutations (A661C and N663C) in the SH2 domain. Better rescue was achieved when all four variants were re-expressed or Sα and ΔSα or Sβ and ΔSβ were re-expressed in pairs. Rescue correlated with expression of STAT3-sensitive genes NFKBIA and NFKBIZ. We consider a variety of explanations why a mix of S and ΔS variants of STAT3 should enable survival of ABC DLBCL cells.

Non-directed, carbonate-mediated C–H activation and aerobic C–H oxygenation with Cp*Ir catalysts

Carbonate additives enhance the activity of [Cp*Ir(H₂O)₃](OTf)₂ for non-directed C–H activations and the aerobic C–H oxygenation of alkyl arenes.

Disproportionate growth between the spine and pelvis in patients with thoracic adolescent scoliosis

A self-control ratio, the spine-pelvis index (SPI), was proposed for the assessment of patients with adolescent idiopathic scoliosis (AIS) in this study. The aim was to evaluate the disproportionate growth between the spine and pelvis in these patients using SPI. A total of 64 female patients with thoracic AIS were randomly enrolled between December 2010 and October 2012 (mean age 13 years, standard deviation (sd) 2.17; 9 to 18) and a further 73 healthy female patients with a mean age of 12.4 years (mean age 12.4 years, sd 2.24; 9 to 18), were randomly selected from a normal control database at our centre. The radiographic parameters measured included length of spine (LOS), height of spine (HOS), length of thoracic vertebrae (LOT), height of thoracic vertebrae (HOT), width of pelvis (WOP), height of pelvis (HOP) and width of thorax (WOT). SPI was defined as the ratio LOS/HOP. The SPI and LOT/HOP in patients with AIS showed a significant increase when compared with normal girls (p < 0.001 and p < 0.001 respectively), implying an abnormal pattern of growth of the spine relative to the pelvis in patients with AIS.

No significant difference in SPI was found in different age groups in the control group, making the SPI an age-independent parameter with a mean value of 2.219 (2.164 to 2.239). We also found that the SPI was not related to maturity in the control group.

This study, for the first time, used a self-control ratio to confirm the disproportionate patterns of growth of the spine and pelvis in patients with thoracic AIS, highlighting that the SPI is not affected by age or maturity.

Cite this article: Bone Joint J 2015;97-B:1668–74.

Avian sarcoma and leukosis virus gag gene in the Anser anser domesticus genome

Endogenous retroviruses are regarded as ideal genetic markers for evolutionary analyses. Birds were some of the initial vertebrates found to contain endogenous retroviruses. However, few studies have investigated the presence and distribution of endogenous retroviruses in goose. In this study, we detected the avian sarcoma and leukosis virus gag gene in the genomic DNA of 8 Chinese native breeds using polymerase chain reaction method. The results indicated that a 1.2-kb avian sarcoma and leukosis virus gag sequence was integrated into all 8 goose breeds. The mean genetic pairwise distance was 0.918% among the investigated geese. To the best of our knowledge, this is the first report demonstrating the presence of the endogenous retroviruses in the domestic goose genome. The genetic structure should be further examined in the domestic goose.

Clinical significance of serum procalcitonin level monitoring on early diagnosis of severe pneumonia on children

OBJECTIVE

To discuss the method for early diagnosis of severe pneumonia on children.

PATIENTS AND METHODS

Fifty-six children with severe pneumonia were enrolled from Department of Pediatrics and Intensive Care Unit (ICU) of our hospital and divided into two groups according to parasitological detection: bacterial pneumonia group consisting of 34 children patients and non-bacterial pneumonia group of 32 children patients. In the meanwhile, 37 healthy children, who were confirmed without infection through physical examination, were also enrolled and grouped in into normal control group. Peripheral venous blood of all children was collected to detect their procalcitonin (PCT).

RESULTS

PCT level of patients in bacterial pneumonia group was significantly higher than that in the non-bacterial pneumonia group and control group, and difference had statistical significance (p < 0.01); serum PCT level on patients in bacterial pneumonia group before and after treatment had statistical significance (p < 0.01); serum PCT level on patients in non-bacterial pneumonia group before and after treatment had no statistical significance (p > 0.05).

CONCLUSIONS

PCT was a very important biomarker for the diagnosis of bacterial infection and also a sensitive indicator for the distinction of child bacterial pneumonia and non-bacterial pneumonia. It had significant clinical diagnosis and differential diagnosis value.

Multiple tooth loss is associated with vascular cognitive impairment in subjects with acute ischemic stroke

BACKGROUND AND OBJECTIVE

Emerging evidence shows that tooth loss is associated with cognitive impairment and dementia. Vascular cognitive impairment (VCI) is a common consequence of ischemic stroke. This study investigated the association of tooth loss with VCI in patients with acute stroke.

MATERIAL AND METHODS

A total of 161 subjects with acute ischemic stroke were recruited. Within 1 wk after admission, fasting blood tests were undertaken and the number of teeth present was recorded. VCI was evaluated with the Montreal Cognitive Assessment (MoCA).

RESULTS

The patients with loss of ≥ 8 teeth exhibited significantly lower MoCA values as compared to those with loss of ≤ 7 teeth (13.2 ± 6.6 vs. 17.3 ± 6.0, p < 0.001). Multivariate logistic regression analysis showed that loss of ≥ 8 teeth (OR = 3.1, 95% CI: 1.2-7.9, p = 0.02) and stroke history (OR = 3.8, 95% CI: 1.1-14.1, p = 0.04) were significantly associated with VCI (MoCA score ≤ 20.0).

CONCLUSION

Within the limitations of this study, the current findings provide the first evidence that multiple tooth loss is independently associated with VCI in patients with acute ischemic stroke.

Cascade Raman sideband generation and orbital angular momentum relations for paraxial beam modes

In this work, the nonlinear parametric interaction of optical radiation in various transverse modes in a Raman-active medium is investigated both experimentally and theoretically. Verification of the orbital angular momentum algebra (OAM-algebra) [Strohaber et al.,Opt. Lett.37,3411 (2012)] was performed for high-order Laguerre Gaussian modes ℓ>1. It was found that this same algebra also describes the coherent transfer of OAM when Ince-Gaussian modes were used. New theoretical considerations extend the OAM-algebra to even and odd Laguerre Gaussian, and Hermite Gaussian beam modes through a change of basis. The results of this work provide details in the spatiotemporal synthesis of custom broadband pulses of radiation from Raman sideband generation.

Beta-interferon exposure and onset of secondary progressive multiple sclerosis

BACKGROUND AND PURPOSE

Beta-interferons (IFNβ) are the most widely prescribed drugs for patients with multiple sclerosis (MS). However, whether or not treatment with IFNβ can delay secondary progressive MS (SPMS) onset remains unknown. Our aim was to examine the association between IFNβ exposure and SPMS onset in patients with relapsing-remitting MS (RRMS).

METHODS

A retrospective cohort study using British Columbia (Canada) population-based clinical and health administrative data (1985-2008) was conducted. RRMS patients treated with IFNβ (n = 794) were compared with untreated contemporary (n = 933) and historical (n = 837) controls. Cohort entry was the first clinic visit during which patients became eligible for IFNβ treatment (baseline). The outcome was time from baseline to SPMS onset. Cox regression models with IFNβ as a time-dependent exposure were adjusted for sex, and baseline age, disease duration, disability, *socioeconomic status and *comorbidities (*available for the contemporary cohorts only). Additional analyses included propensity score adjustment.

RESULTS

The median follow-up for the IFNβ-treated, untreated contemporary and historical controls were 5.7, 3.7 and 7.3 years, and the proportions of patients reaching SPMS were 9.2%, 11.8% and 32.9%, respectively. After adjustment for confounders, IFNβ exposure was not associated with the risk of reaching SPMS when either the contemporary or the historical untreated cohorts were considered (hazard ratio 1.07; 95% confidence interval 0.93-1.48, and hazard ratio 1.04; 95% confidence interval 0.74-1.46, respectively). Further adjustments and the propensity score yielded results consistent with the main analysis.

CONCLUSIONS

Amongst patients with RRMS, use of IFNβ was not associated with a delayed onset of SPMS.

Glycosyltransferase-mediated Sweet Modification in Oral Streptococci

Bacterial glycosyltransferases play important roles in bacterial fitness and virulence. Oral streptococci have evolved diverse strategies to survive and thrive in the carbohydrate-rich oral cavity. In this review, we discuss 2 important biological processes mediated by 2 distinct groups of glycosyltransferases in oral streptococci that are important for bacterial colonization and virulence. The first process is the glycosylation of highly conserved serine-rich repeat adhesins by a series of glycosyltransferases. Using Streptococcus parasanguinis as a model, we highlight new features of several glycosyltransferases that sequentially modify the serine-rich glycoprotein Fap1. Distinct features of a novel glycosyltransferase fold from a domain of unknown function 1792 are contrasted with common properties of canonical glycosyltransferases. The second biological process we cover is involved in building sticky glucan matrix to establish cariogenic biofilms by an important opportunistic pathogen Streptococcus mutans through the action of a family of 3 glucosyltransferases. We focus on discussing the structural feature of this family as a glycoside hydrolase family of enzymes. While the 2 processes are distinct, they all produce carbohydrate-coated biomolecules, which enable bacteria to stick better in the complex oral microbiome. Understanding the making of the sweet modification presents a unique opportunity to develop novel antiadhesion and antibiofilm strategies to fight infections by oral streptococci and beyond.

Distribution of pilus islands and alpha-like protein genes of group B Streptococcus colonized in pregnant women in Beijing, China

Group B Streptococcus (GBS) is one of the major pathogens of severe newborn sepsis and meningitis. Understanding its regional molecular epidemiology is helpful for regulating efficient prevention practice. A total of 160 GBS strains were collected from colonized pregnant women in six hospital settings in Beijing, China. Polymerase chain reaction (PCR) assays were used to identify the pilus island (PI), alp genes profiling of the alpha-like protein family, and capsular polysaccharide (cps) serotyping. The clonal relationships between strains were investigated using multilocus sequence typing (MLST). All isolates carried at least one pilus island. The most frequently detected pilus island was PI-2a alone (70 isolates, 43.8 %). The most prevalent alp gene was rib (60 isolates, 37.5 %). Moreover, a strong association was noted between alp genes, serotyping, and pilus island profiles. The GBS isolates under study hinted similar molecular epidemical characteristics in Beijing to those reported worldwide, but having their regional distributional features.

Investigation of killer cell immunoglobulin-like receptors KIR2DL2 and KIR2DL3 diversity and identification of ten novel KIR2DL3 alleles in the Chinese Han population

KIR2DL2 and KIR2DL3 are important inhibitory receptors that recognize a subset of HLA-C allelic products carrying Ser77 and Asn80. In this study, we have determined KIR2DL2 and KIR2DL3 diversity in the Chinese Han population by a PCR sequence-based typing. Based on sequencing, the coding regions of 166 Chinese Han individuals, seven new polymorphic sites (238G>A, 405G>A, 476A>G, 550G>A, 608G>A, 789T>C, 947T>C) were found. KIR2DL2*00301, *00101, KIR2DL3*00101,*00201,*013, *015 and ten new KIR2DL3 variants (KIR2DL3*00105, 00106, 00107, 00108, 019, 020, 021, 022, 023 and 024) were identified, of which KIR2DL3*00101 was the most frequent allele. Compared with the sequences of KIR2DL3*00101, all sequences of 2DL3*00105, 2DL3*00106, 2DL3*00107 and 2DL3*00108 had one nucleotide substitution(789T>C, 261C>T, 489G>A and 405G>A),but none resulted in amino acid change. An A>G substitution was observed in nucleotide position 476 in 2DL3*019, 608 G>A in 2DL3*020, 824T>C in 2DL3*021 and 238 G>A in 2DL3*023. In addition, 2DL3*022 probably arose from 2DL3*00201 with a nucleotide substitution G>A at 550. There were more HLA-C1 positive individuals than HLA-C2. In conclusion, the data of allelic polymorphism for KIR2DL2 and KIR2DL3 were obtained in the Chinese Han population and ten novel KIR2DL3 alleles were identified.