Fully printed minimum port flexible interdigital electrode sensor arrays

Screen-printed interdigital electrode-based flexible pressure sensor arrays play a crucial role in human-computer interaction and health monitoring due to their simplicity of fabrication. However, the long-standing challenge of how to reduce the number of electrical output ports of interdigital electrodes to facilitate integration with back-end circuits is still commonly ignored. Here, we propose a screen-printing strategy to avoid wire cross-planes for rapid fabrication of flexible pressure sensor arrays. By innovatively introducing an insulating ink to realize electrical insulation and three-dimensional interconnection of wire crossings, the improved sensor array (4 × 4) successfully reduces the number of output ports from 17 to 8. In addition, we further constructed microstructures on the laser-etched electrode surfaces and the sensitive layer, which enabled the sensor to achieve a sensitivity as high as 17 567.5 kPa-1 in the range of 0-50 kPa. Moreover, we integrated the sensors with back-end circuits for the precise detection of tactile and physiological information. This provides a reliable method for preparing high-performance flexible sensor arrays and large-scale integration of microsensors.

Laparoscopic posterior pelvic exenteration is safe and feasible for locally advanced primary rectal cancer in female patients: a comparative study from China PelvEx collaborative

PURPOSE

Posterior pelvic exenteration (PPE) for locally advanced rectal cancer is a technical and challenging procedure. The safety and feasibility of laparoscopic PPE remain to be determined. This study aims to compare short-term and survival outcomes of laparoscopic PPE (LPPE) with open PPE (OPPE) in female patients.

METHOD

From January 2015 to December 2020, data from 105 female patients who underwent PPE at three institutions were retrospectively analyzed. The short-term and oncological outcomes between LPPE and OPPE were compared.

RESULTS

A total of 54 cases with LPPE and 51 cases with OPPE were enrolled. The operative time (240 vs. 295 min, p = 0.009), blood loss (100 vs. 300 ml, p < 0.001), surgical site infection (SSI) rate (20.4% vs. 58.8%, p = 0.003), urinary retention rate (3.7% vs. 17.6%, p = 0.020), and postoperative hospital stay (10 vs. 13 days, p = 0.009) were significantly lower in the LPPE group. The two groups showed no significant differences in the local recurrence rate (p = 0.296), 3-year overall survival (p = 0.129), or 3-year disease-free survival (p = 0.082). A higher CEA level (HR 1.02, p = 0.002), poor tumor differentiation (HR 3.05, p = 0.004), and (y)pT4b stage (HR 2.35, p = 0.035) were independent risk factors for disease-free survival.

CONCLUSION

LPPE is safe and feasible for locally advanced rectal cancers and shows lower operative time and blood loss, fewer SSI complications, and better preservation of bladder function without compromising oncological outcomes.

Design of a Low-Frequency Dielectrophoresis-Based Arc Microfluidic Chip for Multigroup Cell Sorting

Dielectrophoresis technology is applied to microfluidic chips to achieve microscopic control of cells. Currently, microfluidic chips based on dielectrophoresis have certain limitations in terms of cell sorting species, in order to explore a microfluidic chip with excellent performance and high versatility. In this paper, we designed a microfluidic chip that can be used for continuous cell sorting, with the structural design of a curved channel and curved double side electrodes. CM factors were calculated for eight human healthy blood cells and cancerous cells using the software MyDEP, the simulation of various blood cells sorting and the simulation of the joule heat effect of the microfluidic chip were completed using the software COMSOL Multiphysics. The effect of voltage and inlet flow velocity on the simulation results was discussed using the control variables method. We found feasible parameters from simulation results under different voltages and inlet flow velocities, and the feasibility of the design was verified from multiple perspectives by measuring cell movement trajectories, cell recovery rate and separation purity. This paper provides a universal method for cell, particle and even protein sorting.

Application and realization of Norland optical adhesive 73 novel photosensitive macromolecular material for the rapid preparation of periodically tunable nanoscale gratings

Periodically tunable nano-gratings have an irreplaceable role in spectral scanning and optical communication, but the performance of gratings manufactured from different materials varies considerably, and the development of superior materials has energized the preparation of high-precision devices. This paper presents a nanoscale preparation process based on Norland Optical Adhesive 73 (NOA73), which enables the rapid preparation of periodically tunable nano-gratings with up to 100% light transmission. The powerful fluidity and shear rate of NOA73 make it uniquely suited to the preparation of precision devices, allowing the production of up to dense grating structures and offering the possibility of making nanoscale gratings. This paper uses multi-angle hierarchical lithography, die stretching, and replication to achieve further improvements in accuracy and successfully prepare gratings with a period of 500 nm. The successful preparation of NOA73 nano-gratings demonstrates the practicality of NOA73 as a material for precision device fabrication.

Cigarette Smoke Exposure Inhibits Osteoclast Apoptosis via the mtROS Pathway

It is widely known that smoking is a risk factor for bone loss and plays a key role in osteopenia. Despite this well-known association, the mechanisms by which smoking affects bone have not been definitively established. Since smoking increases bone loss and potentially affects bone resorption in response to mechanical force, we investigated the impact of cigarette smoke on osteoclast numbers and underlying mechanisms in a mouse model of orthodontic tooth movement (OTM). The experimental group was exposed to once-daily cigarette smoke while the control group was not, and tooth movement distance and osteoclast numbers were assessed. In addition, the effect of cigarette smoke extract (CSE) on osteoclast precursor proliferation and osteoclast apoptosis was assessed in vitro. We found that cigarette smoke exposure enhanced bone remodeling stimulated by mechanical force and increased osteoclast numbers in vivo. Also, CSE increased the number of osteoclasts by inhibiting osteoclast apoptosis via the mitochondrial reactive oxygen species/cytochrome C/caspase 3 pathway in vitro. Moreover, exposure of mice to cigarette smoke affected bone marrow cells, leading to increased formation of osteoclasts in vitro. This study identifies a previously unknown mechanism of how smoking has a detrimental impact on bone.

Downregulation of GNAS inhibits osteogenesis of bone marrow mesenchymal stem cells and promotes osteoporosis through the Wnt pathway

OBJECTIVE

This study aims to explore the role of GNAS in accelerating the progression of osteoporosis by inhibiting osteogenesis of BMSCs by the Wnt pathway.

PATIENTS AND METHODS

GNAS levels in OP tissues and BMSCs undergoing osteogenesis for different time points were detected. Regulatory effects of GNAS on osteogenesis-related gene expressions, ALP activity, capability of mineralization, and activation of the Wnt pathway in BMSCs were assessed through a series of functional experiments. At last, rescue experiments were performed to further verify the significance of the Wnt pathway during GNAS-mediated osteogenesis development.

RESULTS

GNAS was downregulated in OP tissues relative to normal bone tissues. With the prolongation of osteogenesis, GNAS level gradually increased in BMSCs. Knockdown of GNAS downregulated expression levels of ALP and RUNX2, and attenuated ALP activity and capability of mineralization in BMSCs. GNAS was able to activate the Wnt pathway in BMSCs. Notably, overexpression of Wnt3a could reverse the regulatory effects of GNAS on osteogenesis-related gene expressions, ALP activity, and capability of mineralization in BMSCs.

CONCLUSIONS

Downregulation of GNAS suppresses osteogenesis of BMSCs through the Wnt pathway, thus aggravating the progression of osteoporosis.

Automatic precursor recognition and real-time forecasting of sudden explosive volcanic eruptions at Whakaari, New Zealand

Sudden steam-driven eruptions strike without warning and are a leading cause of fatalities at touristic volcanoes. Recent deaths following the 2019 Whakaari eruption in New Zealand expose a need for accurate, short-term forecasting. However, current volcano alert systems are heuristic and too slowly updated with human input. Here, we show that a structured machine learning approach can detect eruption precursors in real-time seismic data streamed from Whakaari. We identify four-hour energy bursts that occur hours to days before most eruptions and suggest these indicate charging of the vent hydrothermal system by hot magmatic fluids. We developed a model to issue short-term alerts of elevated eruption likelihood and show that, under cross-validation testing, it could provide advanced warning of an unseen eruption in four out of five instances, including at least four hours warning for the 2019 eruption. This makes a strong case to adopt real-time forecasting models at active volcanoes.

In this study, the authors investigate the predictability of sudden eruptions, motivated by the 2019 eruption at Whakaari (White Island), New Zealand. The paper proposes a machine learning approach that is able to identify eruption precursors in data streaming from a single seismic station at Whakaari.

Pharmacological inhibition of β-catenin/BCL9 interaction overcomes resistance to immune checkpoint blockades by modulating Treg cells

The Wnt/β-catenin (β-cat) pathway plays a critical role in cancer. Using hydrocarbon-stapled peptide technologies, we aim to develop potent, selective inhibitors targeting this pathway by disrupting the interaction of β-cat with its coactivators B-cell lymphoma 9 (BCL9) and B-cell lymphoma 9-like (B9L). We identified a set of peptides, including hsBCL9CT-24, that robustly inhibits the activity of β-cat and suppresses cancer cell growth. In animal models, these peptides exhibit potent anti-tumor effects, favorable pharmacokinetic profiles, and minimal toxicities. Markedly, these peptides promote intratumoral infiltration of cytotoxic T cells by reducing regulatory T cells (Treg) and increasing dendritic cells (DCs), therefore sensitizing cancer cells to PD-1 inhibitors. Given the strong correlation between Treg infiltration and APC mutation in colorectal cancers, it indicates our peptides can reactivate anti-cancer immune response suppressed by the oncogenic Wnt pathway. In summary, we report a promising strategy for cancer therapy by pharmacological inhibition of the Wnt/β-cat signaling.

A polymorphic MYC response element in KBTBD11 influences colorectal cancer risk, especially in interaction with an MYC-regulated SNP rs6983267

Background

MYC is a well-established cancer driver gene regulating the expression of numerous genes, indicating that polymorphisms in MYC response elements could affect tumorigenesis through altering MYC regulation. We performed integrative multistage study to evaluate the effects of variants in MYC response elements and colorectal cancer (CRC) risk.

Patients and methods

We systematically integrated ChIP-Seq, DNase-Seq and transcription factor motif data to screen variants with potential ability to affect the MYC binding affinity. Then, we conducted a two-stage case-control study, totally consisting of 4830 CRC cases and 4759 controls in Chinese population to identify risk polymorphisms and interactions. The effects of risk variants were confirmed by functional assays in CRC LoVo, SW480 and HCT15 cells.

Results

We identified a novel polymorphism rs11777210 in KBTBD11 significantly associated with CRC susceptibility (P = 2.43 × 10-12). Notably, we observed a significant interaction between rs11777210 and MYC nearby rs6983267 (P-multi = 0.003, P-add = 0.005), subjects carrying rs6983267 GG and rs11777210 CC genotypes showing higher susceptibility to CRC (2.83-fold) than those carrying rs6983267 TT and rs11777210 TT genotypes. We further demonstrated that rs6983267 T > G increased MYC expression, and MYC bound to and negatively regulated KBTBD11 expression when the rs11777210 C risk allele was present. KBTBD11 was downregulated in tumor tissues, and KBTBD11 knockdown promoted cell proliferation and inhibited cell apoptosis.

Conclusion

The rs11777210 is a potential predictive biomarker of CRC susceptibility, and KBTBD11 functions as a putative tumor suppressor in tumorigenesis. Our study highlighted the high CRC risk of people carrying rs6983267 G and rs11777210 C alleles, and provided possible biological mechanism of the interaction.

Measurements of the Thermal Resistivity of InAlAs, InGaAs, and InAlAs/InGaAs Superlattices

Thermal management efforts in nanoscale devices must consider both the thermal properties of the constituent materials and the interfaces connecting them. It is currently unclear whether alloy/alloy semiconductor superlattices such as InAlAs/InGaAs have lower thermal conductivities than their constituent alloys. We report measurements of the crossplane thermal resistivity of InAlAs/InGaAs superlattices at room temperature, showing that the superlattice resistivities are larger by a factor of 1.2-1.6 than that of the constituent bulk materials, depending on the strain state and composition. We show that the additional resistance present in these superlattices can be tuned by a factor of 2.5 by altering the lattice mismatch and thereby the phonon-mode mismatch at the interfaces, a principle that is commonly assumed for superlattices but has not been experimentally verified without adding new elements to the layers. We find that the additional resistance in superlattices does not increase significantly when the layer thickness is decreased from 4 to 2 nm. We also report measurements of 250-1000 nm thick films of undoped InGaAs and InAlAs lattice-matched to InP substrates, for there is no published thermal conductivity value for the latter, and we find it to be 2.24 ± 0.09 at 22 °C, which is ∼2.7 times smaller than the widely used estimates.

Conductive Atomic Force Microscope Study of Bipolar and Threshold Resistive Switching in 2D Hexagonal Boron Nitride Films

This study investigates the resistive switching characteristics and underlying mechanism in 2D layered hexagonal boron nitride (h-BN) dielectric films using conductive atomic force microscopy. A combination of bipolar and threshold resistive switching is observed consistently on multi-layer h-BN/Cu stacks in the low power regime with current compliance (I_comp) of less than 100 nA. Standard random telegraph noise signatures were observed in the low resistance state (LRS), similar to the trends in oxygen vacancy-based RRAM devices. While h-BN appears to be a good candidate in terms of switching performance and endurance, it performs poorly in terms of retention lifetime due to the self-recovery of LRS state (similar to recovery of soft breakdown in oxide-based dielectrics) that is consistently observed at all locations without requiring any change in the voltage polarity for I_comp ~1–100 nA.

[Treatment strategies of complex lesions in patients with acute Stanford type A dissection of important branches involvement]

Acute Stanford type A aortic dissection with important branches involved is more complex, could lead to organ malperfusion syndrome even organ failure. The understanding of pathological anatomy, classification, staging, and the pathophysiological change has increasingly mature, but not complete. In addition, the treatment strategy for complex lesions is diversified, some questions may not reach consensus. Fully understanding of the anatomical and pathophysiology is very important for surgeons to choose reasonable treatment strategy. As the rapid development of the basic research, imaging techniques and the concept of surgery procedures, the manage technique of Stanfrod type A dissection and branch vessels at the same time is getting seriously, the related issues also need further discussions.

Abstract P1-01-17: Establishment and preliminary clinical application of breast cancer CTC detection kit based on immune magnetic lipid microsphere/human breast mammaglobin

Objective

To explore the effect of breast cancer CTC detection kit based on immune magnetic lipid microsphere (IML) separation and human breast mammaglobin (hMAN) identification, we combined epithelial cell adhesion molecule (EpCAM) IML enrichment and immune fluorescence staining of CK/hMAN (IML/hM-BCD) method.

Methods

74 patients with metastatic breast cancer (MBC) were selected to validate the performance of our integrated CTC capture platform by carrying out side-by-side comparisons with the Cellsearch assay using the same sample. In each study, 15 mL blood was divided equally to identify CTC numbers by employing either Cellsearch and our platform.

Results

In MBC patients, the rates of diagnostic positive detection of Cellsearch and IML/hM-BCD method were 50% and 83.4%, respectively. The IML/hM-BCD method presented a greater ability to capture CTCs from MBC patients. A significant difference in the number (1~5) of CTCs captured by IMLM was observed in the images (2-fold more for IMLM vs CellsearchTM, P&lt;0.001). Furthermore, the morphology and footprint sizes of the cells detected by IML/hM-BCD method offer another approach to validating these observations from the perspectives of cell pathology and cytology. The combined information was utilized to delineate CTCs (DAPI+/CK+/CD45-, cell size &gt; 5 µm) from WBCs (DAPI+/CK-/CD45+, cell size &lt; 15 µm) and cellular debris. Our immunomagnetic lipid microsphere captured significantly different CTC numbers that corresponded to the patients' clinical data.

Conclusions

The panel of IML separation and combined CK/hMAN identification may serve as representative enrichment and biomarkers for CTCs, thus it presents potentially significant valve for monitoring early metastasis, therapeutic efficacy and prognosis for the patients with breast cancer.

Citation Format: Yang B, Wu J, Liang X, Mei S, Zhou B. Establishment and preliminary clinical application of breast cancer CTC detection kit based on immune magnetic lipid microsphere/human breast mammaglobin [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-01-17.

HLA-B*1502 increases the risk of phenytoin or lamotrigine induced Stevens-Johnson Syndrome/toxic epidermal necrolysis: evidence from a meta-analysis of nine case-control studies

BACKGROUND AND STUDY AIMS

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are fatal adverse cutaneous drug reactions which may be induced by phenytoin (PHT) or lamotrigine (LTG). The objective of this study was to analyze the association of human leukocyte antigen (HLA)-B*1502 and PHT or LTG induced SJS/TEN.

PATIENTS AND METHODS

All the participants were epileptic patients and the SJS/TEN were induced by PHT or LTG. The presence or absence of the HLA-B*1502 allele of all the patients was determined. ISI Web of Knowledge, PubMed, ScienceDirect, EMBASE, and Cochrane Register of Controlled Trials (CENTRAL) data were searched for the literature published before April 2014. Meta-analysis was performed using Review Manager 5.2 software.

RESULTS

From 256 citations, 6 English studies were included that involved 480 epilepsy patients. Meta-analysis showed that odd ratio (OR) of PHT and LTG were 5.65 [95% CI: 2.76-11.57] and 4.51 [95% CI: 1.57-12.98], respectively. Funnel plot analysis showed symmetry, indicting less possible publication bias and the results were partly reliable.

CONCLUSION

There is a significant association between HLA-B*1502 and PHT or LTG-induced SJS/TEN.

Genomic and transcriptomic alterations following hybridisation and genome doubling in trigenomic allohexaploid Brassica carinata × Brassica rapa

Allopolyploidisation is a prominent evolutionary force that involves two major events: interspecific hybridisation and genome doubling. Both events have important functional consequences in shaping the genomic architecture of the neo-allopolyploids. The respective effects of hybridisation and genome doubling upon genomic and transcriptomic changes in Brassica allopolyploids are unresolved. In this study, amplified fragment length polymorphism (AFLP), methylation-sensitive amplification polymorphism (MSAP) and cDNA-AFLP approaches were used to track genetic, epigenetic and transcriptional changes in both allohexaploid Brassica (ArArBcBcCcCc genome) and triploid hybrids (ArBcCc genome). Results from these groups were compared with each other and also to their parents Brassica carinata (BBCC genome) and Brassica rapa (AA genome). Rapid and dramatic genetic, DNA methylation and gene expression changes were detected in the triploid hybrids. During the shift from triploidy to allohexaploidy, some of the hybridisation-induced alterations underwent reversion. Additionally, novel genetic, epigenetic and transcriptional alterations were also detected. The proportions of A-genome-specific DNA methylation and gene expression alterations were significantly greater than those of BC-genome-specific alterations in the triploid hybrids. However, the two parental genomes were equally affected during the ploidy shift. Hemi-CCG methylation changes induced by hybridisation were recovered after genome doubling. Full-CG methylation changes were a more general process initiated in the hybrid and continued after genome doubling. These results indicate that genome doubling could ameliorate genomic and transcriptomic alterations induced by hybridisation and instigate additional alterations in trigenomic Brassica allohexaploids. Moreover, genome doubling also modified hybridisation-induced progenitor genome-biased alterations and epigenetic alteration characteristics.

Distinct cellular responses induced by saporin and a transferrin-saporin conjugate in two different human glioblastoma cell lines

Glioblastoma multiforme (GBM) is the most common primary brain tumour in adults, with a median survival of ~12-18 months post-diagnosis. GBM usually recurs within 12 months post-resection, with poor prognosis. Thus, novel therapeutic strategies to target and kill GBM cells are urgently needed. The marked difference of tumour cells with respect to normal brain cells renders glioblastoma a good candidate for selective targeted therapies. Recent experimental strategies focus on over expressed cell surface receptors. Targeted toxins represent a new class of selective molecules composed by a potent protein toxin and a carrier ligand. Targeted toxins approaches against glioblastoma were under investigation in phase I and II clinical trials with several immunotoxins (IT)/ligand toxins such as IL4-Pseudomonas aeruginosa exotoxin A (IL4-PE, NBI-3001), tumour growth factor fused to PE38, a shorter PE variant, (TGF)alpha-TP-38, IL13-PE38, and a transferrin-C diphtheriae toxin mutant (Tf-CRM107). In this work, we studied the effects of the plant ribosome-inactivating saporin and of its chimera transferrin-saporin against two different GBM cell lines. The data obtained here indicate that cell proliferation is affected by the toxin treatments but that different mechanisms are used, directly linked to the presence of an active or inactive p53. A model is proposed for these alternative intracellular pathways.

Glycosilated nucleolin as marker for human gliomas

Nucleolin is a multifunctional DNA and RNA binding protein involved in regulation of gene transcription, chromatin remodeling, RNA metabolism, and ribosomal RNA synthesis. Nucleolin seems to be over-expressed in highly proliferative cells and is involved in many aspect of gene expression: DNA recombination and replication, RNA transcription by RNA polymerase I and II, rRNA processing, mRNA stabilization, cytokinesis, and apoptosis. Although nucleolin is localized predominantly in the nucleolus, it has also been shown to be localized in a phosphorylated/glycolsilated form on the cell surface of different cells. Numerous articles dealing with surface nucleolin targeting for tumor therapy have been recently published. However, at present, no extensive informations are so far available for the presence of nucleolin in human gliomas. In the present work we investigated on the presence and localization of nucleolin in glioma on glioma specimens at different grade of malignancy and on primary glioma cell cultures derived by surgical resection, trying to correlate the presence of glycosilated membrane nucleolin with the malignancy grade. To this purpose an antibody produced by us against gp273 protein, demonstrated to recognized the glycosilated surface nucleolin, has been used. The results obtained demonstrate that surface nucleolin increase with the malignancy grade thus suggesting that it may constitute a histopathological marker for glioma grading and a possible tool for targeted therapy.

Patients with profuse hair shedding may reveal anagen hair dystrophy: a diagnostic clue of alopecia areata incognita

BACKGROUND

Several patients, especially women, seek advice because of hair loss. They may be diagnosed clinically as having telogen effluvium (TE) or androgenetic alopecia (AGA), but histopathology may reveal that a proportion of them have in fact alopecia areata incognita (AAI).

OBJECTIVES

To detect dystrophic anagen hairs in such patients.

METHODS

We studied 1932 patients with hair loss and no signs of classical alopecia areata. They were submitted to the modified wash test (which counts the total number of telogen hairs lost and the percentage of vellus hairs) and divided into patients having pure TE (403), patients with AGA+TE (1235) and patients with pure AGA (294). Dystrophic hairs were detected with a low magnification microscope.

RESULTS

Dystrophic hairs were observed in 13 patients with TE (3.2%), in 54 with AGA+TE (4.4%) and in none with AGA. In addition, 7 patients with TE and 32 with AGA+TE developed small patches of alopecia areata in 6 to 9 weeks. No patches developed in patients with AGA.

CONCLUSIONS

The presence of dystrophic hairs and the development of patches of alopecia areata (and their absence in pure AGA) provide a first evidence of the possibility that within the heterogenous condition named TE some patients have in fact AAI.

Surface engineering of artificial heart valve disks using nanostructured thin films deposited by chemical vapour deposition and sol-gel methods

Pyrolytic carbon (PyC) is widely used in manufacturing commercial artificial heart valve disks (HVD). Although PyC is commonly used in HVD, it is not the best material for this application since its blood compatibility is not ideal for prolonged clinical use. As a result thrombosis often occurs and the patients are required to take anti-coagulation drugs on a regular basis in order to minimize the formation of thrombosis. However, anti-coagulation therapy gives rise to some detrimental side effects in patients. Therefore, it is extremely urgent that newer and more technically advanced materials with better surface and bulk properties are developed. In this paper, we report the mechanical properties of PyC-HVD, i.e. strength, wear resistance and coefficient of friction. The strength of the material was assessed using Brinell indentation tests. Furthermore, wear resistance and coefficient of friction values were obtained from pin-on-disk testing. The micro-structural properties of PyC were characterized using XRD, Raman spectroscopy and SEM analysis. Also in this paper we report the preparation of freestanding nanocrystalline diamond films (FSND) using the time-modulated chemical vapour deposition (TMCVD) process. Furthermore, the sol-gel technique was used to uniformly coat PyC-HVD with dense, nanocrystalline-titanium oxide (nc-TiO2) coatings. The as-grown nc-TiO2 coatings were characterized for microstructure using SEM and XRD analysis.

Steinernema akhursti sp. n. (Nematoda: Steinernematidae) from Yunnan, China

A new species of entomopathogenic nematode, herein described as Steinernema akhursti sp. n., was recovered from soil samples collected from Yunnan Province, the People's Republic of China. Both morphological and molecular data show congruently that S. akhursti sp. n. belongs to the Steinernema feltiae group. It can be separated from all described Steinernema species by the combined morphological and morphometrical characters of various stages of the nematodes. For the first generation male, the new species can be recognized by spicule length 90 +/- 4.6 microm, spicule tip blunt with an aperture on the ventral side, gubernaculum with a long and needle-shaped cuneus, and tail conoid with a prominent mucron on the tip and a concave on ventral side. For the infective juvenile, the combination of the following characters: body length 812 +/- 19 microm, distance from anterior end to excretory pore 59 +/- 1.5 microm, tail length 73 +/- 2.9 microm, E% 77 +/- 4.5, lateral field with six evenly distributed and identical ridges at the middle body portion, and tail with long and slightly constrict hyaline portion can be used to separate the new species from other nematodes. For the female, the new species is characterized by: tail conoid with a short mucron and slightly swelling anal portion and a symmetrical, slightly protruding vulva with conspicuous double-flapped epiptygma. The nematode can be separated from other described species of Steinernema by DNA sequences of either a partial 28S rDNA or the internal transcribed spacer regions of rDNA and from the closely related species S. feltiae and Steinernema oregonense by cross-breeding tests.

Temperature-induced gelation of concentrated silicon carbide suspensions

Due to the steric barrier provided by the adsorption of the dispersant hypermer KD1 (a polyester/polyamine condensation polymer), stable and low-viscosity suspensions of SiC, Y(2)O(3), and Al(2)O(3) powder mixtures could be prepared in methyl ethyl ketone (MEK)/ethanol (E) solvent with solids loading as high as 60 vol%. The solvency of the dispersant in MEK/E decreased dramatically on cooling. Steady shear viscosity and oscillatory measurements were performed as a function of temperature for suspensions with different solids loading. The viscosity and elastic modulus of suspension increased with decreasing temperature and became more sensitive with the increase of solids loading. The suspensions with solids loading higher than 40 vol% could be solidified with decreasing temperature, but gelation temperature and gelation stiffness decreased with decreasing solids loading. The 60 vol% solid-loaded suspension was a stable and free-flowing fluid at 20 degrees C and gradually transformed to a very highly viscous and elastic system upon cooling to about 13 degrees C. Complete solidification occurred when the temperature was decreased to 5 degrees C. The gelation mechanism was mainly based on the collapse of the adsorbed layer as the temperature decreases, which induced incipient flocculation and formed a stiff network. The gelled body was further strengthened by separation of the dispersant from the suspension.

Cicatricial alopecia; a dermatopathologic and immunopathologic study of 33 patients (pseudopelade of Brocq is not a specific clinico-pathologic entity)

BACKGROUND

Pseudopelade of Brocq (PB) is a permanent progressive scarring alopecia characterized by numerous alopecic patches localized only in the scalp, that tend to coalesce into larger, irregular plaques with policyclic borders. PB can be considered either the final atrophic stage of several scarring disorders such as lichen planus pilaris (LPP) and discoid lupus erythematosus (DLE) (secondary PB) or an autonomous disease (primary PB). The aim of this study was to assess the incidence of primary vs. secondary PB by a combined histopathological and immunopathological study in a series of patients who fulfilled the clinical diagnostic criteria for PB set forth by Braun Falco et al.

METHODS

We studied 33 patients (5 males and 28 females, whose age ranged from 24 to 75 years). The duration of the disease (from onset to biopsy) ranged from 3 months to 8 years. Serum samples were tested for circulating auto-antibodies (antinuclear antibodies anti ENA, anticentromere, anti-Scl70, antithyroid, antigastric parietal cells) circulating immune complexes, total and single fraction (C3, C4) complement activity. The skin biopsies taken from the active advancing margin of the more recent alopecic patch were bisected vertically, one was sent for histopathological examination, and the other for the immunofluorescence studies.

RESULTS

In all patients the serum tests above were found to be negative or normal. Histopathologically, 11 biopsies (33.3%) displayed findings typical for LPP whereas seven cases (21.2%) showed typical DLE features. In the remaining 15 cases (45.5%) histopathological findings were not suggestive of any specific dermatosis. DIF investigations showed findings typical of LPP in six cases (18.1%) and typical of DLE in seven cases (21%). In three cases we did not find findings typical of LPP, DLE, or any other specific dermatitis. In 11 cases no immunological deposits could be detected and therefore were classified as negative.

CONCLUSION

In conclusion, PB is a type of scarring alopecia of the scalp associated with a peculiar clinical presentation and evolution, which cannot be considered an autonomous nosologic entity because in 66.6% of patients it is the end stage of other inflammatory chronic diseases such as LPP and DLE. It is conceivable that even in those cases in which the histopathological and immunopathological findings did not allow for a specific diagnosis, LPP and DLE were also involved. It is noteworthy that in our study the histopathological and the immunopathological examinations did not conflict and often the results were even coincidental, thus confirming the compatibility of the combined histo-immunopathological approach in the diagnostic evaluation of PB.

A case of vesiculo-bullous Darier's disease associated with bipolar psychiatric disorder

We describe the case of a 71-year-old men suffering from Darier's disease since his youth and presenting with intensely itching, vesicular and pustular lesions, localized on his arms, legs and on the ulnar side of his right hand. The patient also had a 30 year-history of bipolar psychiatric disorders. The histopathological examination of lesional skin showed suprabasal acantholytic clefting, hyperparakeratosis, and dyskeratosis. Histopathological and immunopathological (direct and indirect immunofluorescence) results, were consistent with vesiculo-bullous Darier's disease. Corticosteroid therapy with methylprednisolone at low dosage (0.2 mg/kg/day) was started with a quick resolution of the vesicular lesions on his arms and legs.

Dermatitis herpetiformis and vitiligo: report of a case and review of the literature

We describe the case of a 53-year-old woman presenting papulous and papulovesicular lesions that were highly pruritic, localized mostly in the achromic areas of vitiligo and symmetrically distributed on the elbows, the buttocks, the shoulders and the neck. The histopathological examination performed on the elbow's lesional skin showed the presence of neutrophils and fibrin microabscesses at the tips of dermal papillae, with a few eosinophils, and small separations between the dermis and epidermis just over the infiltrate. The overlying epidermis was uninjured. The performed tests detected IgA anti-endomysium, anti-thyrogloblin, anti-smooth muscle and anti-microsomal fraction autoantibodies; DIF showed the presence of IgA granular deposits at the dermo-epidermal junction, prevalently at the tips of dermal papillae. This is the tenth case reported of an association between dermatitis herpetiformis and vitiligo. Although the two disorders both have immunological pathogeneses, we think that the topographic coexistence of both disorders is coincidental.

[Toxicity of anti-herbicide gene (BAR) transgenic rice]

In order to evaluate the safety of anti-herbicide gene(BAR) transgenic rice, acute toxicity experiments, mutation experiments and a 30-day feeding test were conducted. The results were as follows: The oral LD50 for mice and rats was larger than 21.5 g/kg BW and no mutation was found. The rats consuming 16.32 and 64 g/kg BW were in good growth and development at the 30-day feeding test. The body weight, food utilization, routine blood tests, the ratio of organ weight to body weight, and patho-histological observations had no obvious change. The none effect dosage for the transgene rice was 64 g/kg.

[Infection of Ureaplasma urealyticum between parents and their newborns]

OBJECTIVE

To investigate the relationship of ureaplasma urealyticum (UU) infection between parents and their newborns, and the possible influence of the modes of delivery on infants UU infection.

METHODS

The cervical swab samples were obtained from 157 pregnant women around 32-36 gestational weeks for the determination of UU by polymerase chain reaction (PCR). In those UU positive cases, swab samples were taken both from the their husbands' urethra and the their newborns' throat after delivery.

RESULTS

UU was detected in 27 pregnant women (17.2%), among which it was positive in 66.7% of their husbands, 55.6% of the neonates. Out of the 9 infected women whose husbands were negative only 2 neonates were positive, while 72.2% (13/18) of the neonates found UU infection when both of their parents were positive (P < 0.05). The positive rate of neonates was 47.1% in the group of vaginal delivery and 70.0% in the cesarean section group (P > 0.05).

CONCLUSION

The neonatal UU infection is strongly associated with UU infection of their parents, and it is mainly an intrauterine infection rather than infection aquired during delivery.

Cleavage of vasoactive intestinal peptide at multiple sites by autoantibodies

Vasoactive intestinal peptide (VIP) fragments generated by autoantibodies purified from the blood of two human beings were separated and sequenced. Based on the identity of these fragments, seven peptide bonds cleaved by the antibodies were identified. Six of the seven scissile bonds are clustered in the region of VIP spanning residues 14-22 and were cleaved by antibodies from both human subjects. The seventh scissile bond is located at residues 7-8 and was cleaved by antibodies from one of the subjects. The scissile bonds link amino acid residues with different size, charge, and hydrophobicity. The hydrolytic activity of the antibodies was selective in that they failed to hydrolyze polypeptides unrelated in sequence to VIP (insulin and atrial natriuretic peptide). These observations demonstrate substrate specific hydrolysis by naturally occurring antibodies and expand the range of peptide bonds hydrolyzed by these antibodies.