Determination of 11 Kinds of Hair Dyes in Hair-Dyeing Products by Liquid Chromatography-Tandem Mass Spectrometry

Eleven kinds of hair dyes were determined in hair-dyeing products by liquid chromatography-tandem mass spectrometry (MS). The samples were extracted with ultrasound in methanol for 20 min. After centrifugation, the supernatant was diluted with 10% methanol/90% water (v/v). Then, the solution was analyzed by Shim-pack Scepter C18-120 column (100 mm × 2.1 mm, 1.9 μm) plus electrospray ionization-MS/MS. Matrix-matched standard solutions were used to analyze the samples. The limits of detection were from 0.15 to 10 mg/kg, the limits of quantification were from 0.5 to 40 mg/kg and the recovery was from 79.4 to 109.2%. The protocol was selective and accurate and was satisfyingly applied to analyze hair dyes in different kinds of commercial products. 1-Hydroxyethyl-4,5-diaminopyrazole sulfate, hydroxyethyl-p-phenylenediamine sulfate, 2-methyl-5-hydroxyethylaminophenol, 5-amino-6-chloro-o-cresol, 3-nitro-p-hydroxyethylaminophenol and 2-amino-6-chloro-4-nitrophenol were detected in 10 samples with the concentrations between limits of detection and quantification to 9.27 × 104 mg/kg.

Origin of Immediate Damping of Coherent Oscillations in Photoinduced Charge-Density-Wave Transition

In stark contrast to the conventional charge density wave (CDW) materials, the one-dimensional CDW on the In/Si(111) surface exhibits immediate damping of the CDW oscillation during the photoinduced phase transition. Here, we successfully reproduce the experimental observation of the photoinduced CDW transition on the In/Si(111) surface by performing real-time time-dependent density functional theory (rt-TDDFT) simulations. We show that photoexcitation promotes valence electrons from the Si substrate to the empty surface bands composed primarily of the covalent p-p bonding states of the long In-In bonds. Such photoexcitation generates interatomic forces to shorten the long In-In bonds and thus drives the structural transition. After the structural transition, these surface bands undergo a switch among different In-In bonds, causing a rotation of the interatomic forces by about π/6 and thus quickly damping the oscillations in feature CDW modes. These findings provide a deeper understanding of photoinduced phase transitions.

[Research advances in classifications and functions of retinal ganglion cells]

Retinal ganglion cells (RGCs) are the most important type of neurons in the visual pathway. RGC axons exit the eye to form the optic nerve, which connects with the brain. The visual signals carried by RGC axons establish the only link between the outside world and our internal perception of sight. Researches on the morphological, physiological, molecular, and mosaic features of RGCs are of great significance. This article reviews the research advances of RGC classifications, definitive types of RGCs, and selective vulnerability of specific RGC types after various injuries.

Recognition of moyamoya disease and its hemorrhagic risk using deep learning algorithms: sourced from retrospective studies

Although intracranial hemorrhage in moyamoya disease can occur repeatedly, predicting the disease is difficult. Deep learning algorithms developed in recent years provide a new angle for identifying hidden risk factors, evaluating the weight of different factors, and quantitatively evaluating the risk of intracranial hemorrhage in moyamoya disease. To investigate whether convolutional neural network algorithms can be used to recognize moyamoya disease and predict hemorrhagic episodes, we retrospectively selected 460 adult unilateral hemispheres with moyamoya vasculopathy as positive samples for diagnosis modeling, including 418 hemispheres with moyamoya disease and 42 hemispheres with moyamoya syndromes. Another 500 hemispheres with normal vessel appearance were selected as negative samples. We used deep residual neural network (ResNet-152) algorithms to extract features from raw data obtained from digital subtraction angiography of the internal carotid artery, then trained and validated the model. The accuracy, sensitivity, and specificity of the model in identifying unilateral moyamoya vasculopathy were 97.64 ± 0.87%, 96.55 ± 3.44%, and 98.29 ± 0.98%, respectively. The area under the receiver operating characteristic curve was 0.990. We used a combined multi-view conventional neural network algorithm to integrate age, sex, and hemorrhagic factors with features of the digital subtraction angiography. The accuracy of the model in predicting unilateral hemorrhagic risk was 90.69 ± 1.58% and the sensitivity and specificity were 94.12 ± 2.75% and 89.86 ± 3.64%, respectively. The deep learning algorithms we proposed were valuable and might assist in the automatic diagnosis of moyamoya disease and timely recognition of the risk for re-hemorrhage. This study was approved by the Institutional Review Board of Huashan Hospital, Fudan University, China (approved No. 2014-278) on January 12, 2015.

Recognition of Cognitive Impairment in Adult Moyamoya Disease: A Classifier Based on High-Order Resting-State Functional Connectivity Network

Objective: Vascular cognitive impairment (VCI) is a common complication in adult patients with moyamoya disease (MMD), and is reversible by surgical revascularization in its early stage of mild VCI. However, accurate diagnosis of mild VCI is difficult based on neuropsychological examination alone. This study proposed a method of dynamic resting-state functional connectivity (FC) network to recognize global cognitive impairment in MMD. Methods: For MMD, 36 patients with VCI and 43 patients with intact cognition (Non-VCI) were included, as well as 26 normal controls (NCs). Using resting-state fMRI, dynamic low-order FC networks were first constructed with multiple brain regions which were generated through a sliding window approach and correlated in temporal dimension. In order to obtain more information of network interactions along the time, high-order FC networks were established by calculating correlations among each pair of brain regions. Afterwards, a sparse representation-based classifier was constructed to recognize MMD (experiment 1) and its cognitive impairment (experiment 2) with features extracted from both low- and high-order FC networks. Finally, the ten-fold cross-validation strategy was proposed to train and validate the performance of the classifier. Results: The three groups did not differ significantly in demographic features (p > 0.05), while the VCI group exhibited the lowest MMSE scores (p = 0.001). The Non-VCI and NCs groups did not differ significantly in MMSE scores (p = 0.054). As for the classification between MMD and NCs, the area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, and specificity of the classifier reached 90.70, 88.57, 93.67, and 73.08%, respectively. While for the classification between VCI and Non-VCI, the AUC, accuracy, sensitivity, and specificity of the classifier reached 91.02, 84.81, 80.56, and 88.37%, respectively. Conclusion: This study not only develops a promising classifier to recognize VCI in adult MMD in its early stage, but also implies the significance of time-varying properties in dynamic FC networks.

Chinese Stroke Association guidelines for clinical management of cerebrovascular disorders: executive summary and 2019 update of clinical management of spontaneous subarachnoid haemorrhage

Aim

Spontaneous subarachnoid haemorrhage (SAH) caused by ruptured cerebral aneurysm is a severe subtype of haemorrhagic stroke. Although the incidence of SAH is relatively low among all cerebrovascular diseases, the mortality is the highest. The critical management of SAH is challenging. We provide this evidence-based guideline to present current and comprehensive recommendations for the diagnosis and treatment of non-trauma SAH.

Methods

A formal literature search of MEDLINE (1 January 1990-30 June 2019) was performed. Data were synthesised with the use of evidence tables. Writing group members met by teleconference to discuss data-derived recommendations. The Chinese Stroke Association's levels of evidence grading algorithm was used to grade each recommendation. The guideline draft was reviewed by Chinese Stroke Association's Stroke Fellow Committees. It is intended that this guideline be fully updated every 3 years.

Results

Evidence-based guidelines are presented for the care of patients presenting with non-trauma SAH. The focus of the guideline was subdivided into transfer and systems of care, diagnosis flowchart, aetiology and differentiation, prevention of rebleeding, surgical and endovascular repair of ruptured aneurysms, management of vasospasm and delayed cerebral ischaemia, management of hydrocephalus, management of seizures and management of medical complications.

Conclusions

The guideline offers a framework for SAH management. Early professional and aggressive care of SAH might help dramatically.

Minocycline reduces intracerebral hemorrhage-induced white matter injury in piglets

Aims

White matter (WM) injury after intracerebral hemorrhage (ICH) results in poor or even fatal outcomes. As an anti‐inflammatory drug, minocycline has been considered a promising choice to treat brain injury after ICH. However, whether minocycline can reduce WM injury after ICH is still controversial. In the present study, we investigate the effect and underlying mechanism of minocycline on WM injury after ICH.

Methods

An ICH model was induced by an injection of autologous blood into the right frontal lobe of piglets. First, transcriptional analysis was performed at day 1 or 3 to investigate the dynamic changes in neuroinflammatory gene expression in WM after ICH. Second, ICH piglets were treated either with minocycline or with vehicle alone. All piglets then underwent magnetic resonance imaging to measure brain swelling. Brain tissue was used for real‐time polymerase chain reaction (RT‐PCR), immunohistochemistry, Western blot, and electron microscopy.

Results

Transcriptional analysis demonstrated that transforming growth factor‐β (TGF‐β)/mitogen‐activated protein kinase (MAPK) signaling is associated with microglia/macrophage‐mediated inflammation activation after ICH and is then involved in WM injury after ICH in piglets. Minocycline treatment results in less ICH‐induced brain swelling, fewer neurological deficits, and less WM injury in comparison with the vehicle alone. In addition, minocycline reduces microglial activation and alleviates demyelination in white matter after ICH. Finally, we found that minocycline attenuates WM injury by increasing the expression of TGF‐β and suppressing MAPK activation after ICH.

Conclusion

These results indicate that TGF‐β–mediated MAPK signaling contributes to WM injury after ICH, which can be altered by minocycline treatment.

Microstructural damage pattern of vascular cognitive impairment: a comparison between moyamoya disease and cerebrovascular atherosclerotic disease

Moyamoya disease and cerebrovascular atherosclerotic disease are both chronic ischemic diseases with similar presentations of vascular cognitive impairment. The aim of the present study was to investigate the patterns of microstructural damage associated with vascular cognitive impairment in the two diseases. The study recruited 34 patients with moyamoya disease (age 43.9 ± 9.2 years; 20 men and 14 women, 27 patients with cerebrovascular atherosclerotic disease (age: 44.6 ± 7.6 years; 17 men and 10 women), and 31 normal controls (age 43.6 ± 7.3 years; 18 men and 13 women) from Huashan Hospital of Fudan University in China. Cognitive function was assessed using the Mini-Mental State Examination, long-term delayed recall of Auditory Verbal Learning Test, Trail Making Test Part B, and the Symbol Digit Modalities Test. Single-photon emission-computed tomography was used to examine cerebral perfusion. Voxel-based morphometry and tract-based spatial statistics were performed to identify regions of gray matter atrophy and white matter deterioration in patients and normal controls. The results demonstrated that the severity of cognitive impairment was similar between the two diseases in all tested domains. Patients with moyamoya disease and those with cerebrovascular atherosclerotic disease suffered from disturbed supratentorial hemodynamics. Gray matter atrophy in bilateral middle cingulate cortex and parts of the frontal gyrus was prominent in both diseases, but in general, was more severe and more diffuse in those with moyamoya disease. White matter deterioration was significant for both diseases in the genu and body of corpus callosum, in the anterior and superior corona radiation, and in the posterior thalamic radiation, but in moyamoya disease, it was more diffuse and more severe. Vascular cognitive impairment was associated with regional microstructural damage, with a potential link between, gray and white matter damage. Overall, these results provide insight into the pathophysiological nature of vascular cognitive impairment. This study was approved by the Institutional Review Board in Huashan Hospital, China (approval No. 2014-278). This study was registered with ClinicalTrials.gov on December 2, 2014 with the identifier NCT02305407.

Determination of Fluorescent Whitening Agents in Cosmetics and Liquid Detergent by High-Performance Liquid Chromatography with Diode Array Detector in Tandem with Fluorescence Detector

Five distyryl-type fluorescent whitening agents (FWA85, 210, 220, 351, and 353) were determined in cosmetics and liquid detergent by high-performance liquid chromatography with diode array detector in tandem with fluorescence detector. The samples were extracted with ultrasound in 33% acetonitrile for 10 minutes and the components were determined by ion-pair chromatography on an MG C18 column. The limits of detection were from 0.01 to 0.1 mg·kg^-1 and the limits of quantification were from 0.04 to 0.4 mg·kg^-1. The recovery was from 80.7 to 103.3%. A linear relationship was present from 0.10 to 100 µg·ml^-1 of FWAs. The protocol was simple, sensitive, selective, and was successfully applied to analyze distyryl-type FWAs in cosmetics and liquid detergent. FWA351 and FWA85 were detected in several samples with the concentrations of 19.4-1,130 mg·kg^-1.

Epidemiological Features of Nontraumatic Spontaneous Subarachnoid Hemorrhage in China: A Nationwide Hospital-based Multicenter Study

BACKGROUND

Nontraumatic spontaneous subarachnoid hemorrhage (SAH) is associated with a high mortality. This study was conducted to investigate the epidemiological features of nontraumatic spontaneous SAH in China.

METHODS

From January 2006 to December 2008, the clinical data of patients with nontraumatic SAH from 32 major neurosurgical centers of China were evaluated. Emergent digital subtraction angiography (DSA) was performed for the diagnosis of SAH sources in the acute stage of SAH (≤3 days). The results and complications of emergent DSA were analyzed. Repeated DSA or computed tomography angiography (CTA) was suggested 2 weeks later if initial angiographic result was negative.

RESULTS

A total of 2562 patients were enrolled, including 81.4% of aneurysmal SAH and 18.6% of nonaneurysmal SAH. The total complication rate of emergent DSA was 3.9% without any mortality. Among the patients with aneurysmal SAH, 321 cases (15.4%) had multiple aneurysms, and a total of 2435 aneurysms were detected. The aneurysms mostly originated from the anterior communicating artery (30.1%), posterior communicating artery (28.7%), and middle cerebral artery (15.9%). Among the nonaneurysmal SAH cases, 76.5% (n = 365) had negative initial DSA, including 62 cases with peri-mesencephalic nonaneurysmal SAH (PNSAH). Repeated DSA or CTA was performed in 252 patients with negative initial DSA, including 45 PNSAH cases. Among them, the repeated angiographic results remained negative in 45 PNSAH cases, but 28 (13.5%) intracranial aneurysms were detected in the remaining 207 cases. In addition, brain arteriovenous malformation (AVM, 7.5%), Moyamoya disease (7.3%), stenosis or sclerosis of the cerebral artery (2.7%), and dural arteriovenous fistula or carotid cavernous fistula (2.3%) were the major causes of nonaneurysmal SAH.

CONCLUSIONS

DSA can be performed safely for pathological diagnosis in the acute stage of SAH. Ruptured intracranial aneurysms, AVM, and Moyamoya disease are the major causes of SAH detected by emergent DSA in China.

Effect of the nucleotides surrounding the start codon on the translation of foot-and-mouth disease virus RNA

As for the alternative AUGs in foot-and-mouth disease virus (FMDV), nucleotide bias of the context flanking the AUG(2nd) could be used as a strong signal to initiate translation. To determine the role of the specific nucleotide context, dicistronic reporter constructs were engineered to contain different versions of nucleotide context linking between internal ribosome entry site (IRES) and downstream gene. The results indicate that under FMDV IRES-dependent mechanism, the nucleotide contexts flanking start codon can influence the translation initiation efficiencies. The most optimal sequences for both start codons have proved to be UUU AUG(1st) AAC and AAG AUG(2nd) GAA.

Postoperative executive function in adult moyamoya disease: a preliminary study of its functional anatomy and behavioral correlates

OBJECTIVE Chronic frontal hemodynamic disturbances are associated with executive dysfunction in adult patients with moyamoya disease (MMD). However, the impact of surgical revascularization on executive dysfunction and its underlying mechanism remains unclear. The aim of the present study was to examine the postoperative radiological correlates of cognitive improvement and thereby explore its underlying mechanism. METHODS Fourteen patients who met the inclusion criteria were identified at Huashan Hospital, were operated on, and were successfully followed up for 6 months. Postoperative changes in cortical perfusion and regional amplitude of low-frequency fluctuations (ALFF) were examined by SPECT and resting-state functional MRI, respectively. Executive function was evaluated by 2 tests (Trail Making Test Part B and the summation of executive subtests of Memory and Executive Screening [MES-EX]). Follow-up neuropsychological outcomes were then correlated with radiological changes to identify nodes functioning as leading contributors to postoperative executive outcomes. RESULTS All patients underwent successful unilateral bypass procedures, with some operations performed on the left side and some on the right side. At the 6-month follow-up, the baseline and follow-up test scores for the different sides did not differ significantly. The group with good collaterals (Matsushima Grade A, 9 patients) exhibited significantly increased postoperative perfusion (change in [△] hemodynamics) in bilateral frontal (left, p = 0.009; right, p = 0.003) and left parietal lobe (p = 0.014). The Spearman's correlation test suggested that only the right frontal lobe exhibited significant positive postoperative radiological correlates with cognitive performance (△MES-EX vs △hemodynamics, r = 0.620, p = 0.018; △MES-EX vs △ALFF, r = 0.676, p = 0.008; △hemodynamics vs △ALFF, r = 0.547, p = 0.043). Subsequent regional ALFF analysis revealed that the right dorsolateral prefrontal cortex (DLPFC) was the only node in the responsible hemisphere to exhibit significant postoperative changes. CONCLUSIONS The results not only advance our understanding of pathological interactions of postoperative executive performance in adult MMD, but also indicate that the right DLPFC amplitude might be a quantitative predictor of postoperative executive control improvement.

Determination of zinc pyrithione in shampoos by HPLC and HPLC-MS/MS

Methods have been developed for the determination of zinc pyrithione (ZPT) in shampoos using high-performance liquid chromatography (HPLC) and high-performance liquid chromatography-mass spectrometry/mass spectrometry (HPLC-MS/MS). Samples were washed by water first to remove surfactant and water-soluble impurities, then ultrasonic-extracted by acetonitrile-methanol for 30 min, and finally analyzed by MG C18 column (250 mm x 4.6 mm, 5 μm) or RP-18e (100 mm x 3 mm, 2 μm) plus APCI-MS/MS. Limits of detection were determined as 0.015% (HPLC) and 0.003% (HPLC-MS/MS), with a limit of quantization of 0.05% and 0.01%, respectively. The recoveries were 85.8-104% (HPLC) and 87.6-107% (HPLC-MS/MS). A good linear relationship was obtained from 3.20 μg·ml(-1) to 200 μg·ml(-1) (HPLC) and 1.00 μg·ml(-1) to 200 μg·ml(-1) (HPLC-MS/MS). The proposed methods have been successfully applied to the analysis of ZPT in many shampoos. The established two methods were rapid and reproducible with low interference.

Haemodynamic analysis of vessel remodelling in STA-MCA bypass for Moyamoya disease and its impact on bypass patency

The purpose of this study is to estimate the remodelling characteristics of STA-MCA bypass and its influence on patency via the use of computational fluid dynamic (CFD) technology. The reconstructed three-dimensional geometries from MRA were segmented to create computational domains for CFD simulations. Eleven patients, who underwent regular MRA both immediately following surgery and at the six months follow-up, were studied. The flow velocities at STA were measured via the use of quantitative MRA (QMRA) to validate simulation results. STA-MCA bypass patency was confirmed for each patient immediately following surgery. The simulation indicated that the remodelling of the arterial pedicle in nine patients was associated with a reduction in the resistance to flow through the bypass. For these cases, the modelling of a driving pressure of 10mmHg through the bypass at 6 months post-surgery resulted in a 50% greater blood flow than those found immediately following surgery. However, two patients were found to exhibit contradictory patterns of remodelling, in which a highly curved bending at the bypass immediately post-surgery underwent progression, with increased resistance to flow through the bypass at 6 months follow-up, thereby resulting in a modelled flow rate reduction of 50% and 25%, respectively. This study revealed that STA-MCA bypass has a characteristic remodelling that usually reduces flow resistance. The initial morphology of the bypass may have had a significant effect on the outcome of vessel remodelling.

Papillary meningioma: clinical and histopathological observations

Papillary meningioma is a rare subtype of malignant meningiomas, which is classified by the World Health Organization as Grade III. Because of lack of large sample size case studies, many of the specific characteristics of papillary meningioma are unclear. This study investigated by retrospective analysis the clinical, radiological and histopathological findings of 17 papillary meningioma patients who underwent surgical resection or biopsy, to assess the characteristics of papillary meningioma. Eight female and nine male patients were included, with a mean age of 40 (range: 6 to 55) years. Tumors were mostly located in the cerebral convexity and showed irregular margins, absence of a peritumoral rim, heterogeneous enhancement and severe peritumoral brain edema on preoperative images. Brain invasion was often confirmed during the operations, with abundant to exceedingly abundant blood supply. Intratumoral necrosis and mitosis was frequently observed on routinely stained sections. The average MIB-1 labeling index was 6.9%. Seven cases experienced tumor recurrence or progression, while seven patients died 6 to 29 months after operation. Radiation therapy was given in 52.9% of all cases. Univariate analysis showed that only the existence of intratumoral necrosis and incomplete resection correlated with tumor recurrence. The 3-year progression free survival was 66.7% after gross total resection and 63.6% for other cases. The 3-year mortality rate was 50% after gross total resection and 63.6% for other cases. Papillary meningioma has specific clinical and histopathological characteristics. Tumor recurrence (or progression) and mortality are common. Gross total tumor resection resulted in less recurrence and mortality.

Formation of nanostructure and nano-hardness characterization on the meso-scale workpiece by a novel laser indirect shock forming method

The meso-scale workpiece with greatly enhanced mechanical properties is potential to be widely used in the electronics productions and micro-electro mechanical systems. In this study, it demonstrates that the meso-scale cup-shape workpiece with good geometry can be obtained by a novel laser indirect shock forming method. After the forming process, the mechanical properties and microstructures of the formed workpiece were characterized. By transmission electron microscope observation, it was found that a mixed refined microstructure consisting of nano-scale twins embedded in nano-sized grains was produced at the center of the formed sample. Formation of these nanograins could be mainly attributed to two mechanisms: twin-twin intersections and twin∕matrix lamellae fragmentation. By nanoindentation tests, it reveals that the hardness of the sample has increased greatly after laser shock forming and the hardness increases with the laser energy. The elevated hardness originates from a considerable number of nano-scale twins and nanograins, which possess a pretty high strength due to the significant effects of grain boundary strengthening and twin boundary strengthening.

Increased expression of osteopontin in brain arteriovenous malformations

BACKGROUND

The precise mechanisms responsible for the development and growth of intracranial arteriovenous malformations (AVMs) remain unclear. Osteopontin (OPN) is a phosphorylated glycoprotein with diverse functions. This study aimed to analyze the expression of OPN in human brain AVMs.

METHODS

The AVM nidus was surgically obtained from patients with AVM, whereas control brain artery specimens were surgically obtained from patients with epilepsy. Reverse transcription-polymerase chain reaction (RT-PCR) was used to examine the expression of OPN mRNA in biopsy specimens. OPN protein expression was localized by immunohistochemistry. The statistical differences between different groups were assessed by two-way analysis of variance (ANOVA).

RESULTS

We analyzed 36 brain AVM specimens and 8 control brain artery specimens. Eleven patients with brain AVM received embolization treatment, and five underwent gamma knife radiotherapy before resection. Nineteen patients with brain AVM had a history of hemorrhage from AVMs. The expression of OPN mRNA was significantly higher in AVMs than that in the control specimens (25.76 ± 2.71 vs. 21.46 ± 2.01, P < 0.01). There was no statistically significant difference in the extent of OPN mRNA expression between the AVM group with and that without history of hemorrhage (26.13 ± 2.45 vs. 25.34 ± 2.99) or gamma knife radiotherapy (24.39 ± 2.10 vs. 24.53 ± 1.85). However, the difference between the AVM group with and that without embolization treatment history was statistically significant (24.39 ± 2.10 vs. 28.80 ± 1.13, P < 0.01). In the group with gamma knife radiotherapy history, OPN expression was found in arteries with early-stage radio-effect.

CONCLUSIONS

OPN may contribute to the vascular instability of brain AVMs. It may play an important role in the pathophysiological process related to embolization treatment.

Multifunctional surfaces with biomimetic nanofibres and drug-eluting micro-patterns for infection control and bone tissue formation

For long-term orthopaedic implants, the creation of a surface that is repulsive to bacteria while adhesive to tissue cells represents a promising strategy to control infection. To obtain such multifunctional surfaces, two possible approaches were explored to incorporate a model antibiotic, rifampicin (Rf), into the osteogenic polycaprolactone (PCL)/chitosan (CHS) biomimetic nanofibre meshes by (1) blending Rf into the electrospinning solutions and then electrospinning into nanofibres (i.e., Rf-incorporating fibres), or (2) depositing Rf-containing poly(D,L-lactic-co-glycolic) acid (PLGA) micro-patterns onto the PCL/chitosan nanofibre meshes via ink-jet printing (i.e., Rf-eluting micro-pattern/fibre). Rapid release of Rf from both meshes was measured even though a relatively slower release rate was obtained from the Rf-eluting micro-pattern ones. Antibacterial assay with Staphylococcus epidermidis showed that both mesh surfaces could effectively kill bacteria and prevent biofilm formation. However, only Rf-eluting micro-pattern meshes favoured the attachment, spreading and metabolic activity of preosteoblasts in the cell culture study. Furthermore, the Rf-eluting micro-pattern meshes could better support the osteogenic differentiation of preosteoblasts by up-regulating the gene expression of bone markers (type I collagen and alkaline phosphatase). Clearly, compared to Rf-incorporating nanofibre meshes, Rf-eluting micro-patterns could effectively prevent biofilm formation without sacrificing the osteogenic properties of PCL/chitosan nanofibre surfaces. This finding provides an innovative avenue to design multifunctional surfaces for enhancing bone tissue formation while controlling infection.

Treatment of mature landfill leachate by biofilters and Fenton oxidation

A series of processes by biofilter and Fenton oxidation to treat mature landfill leachate has been devised. At a hydraulic loading rate of 20 l m(-3)d(-1), a biofilter packed with aged refuse is found to remove 80% of chemical oxygen demand (COD), 89% of ammonia nitrogen and 96% of total phosphorus (TP). Particularly, TP levels dropped below 1 mg l(-1). The optimal condition for Fenton oxidation was selected to be an initial pH of 5, a dosage of 0.01 and 0.02 mol l(-1) of FeSO(4) and H(2)O(2), respectively, and a duration of 3h, where COD removal efficiency reaches 58.6%, and BOD(5)/COD ratio is raised from 0.05 to 0.20. Subsequent treatment by a biofilter packed with slag reduces COD, ammonia nitrogen levels to less than 100, 25 mg l(-1), respectively. A pilot scale experiment conducted in situ demonstrates that this series of processes exhibits a high efficiency in removing pollutants from mature landfill leachate and it is viable for application.

Leptin plays a role in ruptured human brain arteriovenous malformations

INTRODUCTION

Intracerebral hemorrhage (ICH) is one of the most common clinical manifestations of human brain arteriovenous malformation (BAVM). However, the hemorrhagic mechanism of BAVM is still unclear. Leptin, first discovered in obesity research, has not been systematically studied in BAVM and ICH. We investigated expression and effect of leptin on human BAVM.

METHODS

Specimens were obtained from 6 BAVM patients, who had been divided into either hemorrhagic or non-hemorrhagic groups. Leptin, leptin receptor, and signal transducers and activators of transcription-3 (STAT3) were analyzed by different methods, such as gene chips, reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemistry, and Western blot. Perinidal brain tissue around each BAVM served as control.

RESULTS

Gene chips and RT-PCR found transcriptional leptin raised at least 2 levels in hemorrhagic BAVM. Immunohistochemical slices also showed higher expression of leptin, leptin receptor, and STAT3 on nidus part of hemorrhagic BAVM than non-hemorrhagic ones. On Western blot analysis, hemorrhagic BAVMs had higher levels of leptin (p < 0.01).

CONCLUSIONS

The transcriptional and translational levels of leptin, leptin receptor, and STAT3 were higher in hemorrhagic BAVM, suggesting that leptin may play an important role in the hemorrhagic mechanism of BAVM.

Dural arteriovenous fistula of the sphenobasilar sinus with concomitant meningioma: case report and review of the literature

Dural arteriovenous fistula of the sphenobasilar sinus is a true but rare lesion that connects the meningeal arteries from both the external and internal carotid arteries to the superficial middle cerebral vein (SMCV) and dural sinus. It must be distinguished from other dural arteriovenous fistulas (DAVFs) of the middle cranial fossa, such as cavernous DAVFs and sphenoparietal sinus DAVF, because of differences in the treatment and outcome between these DAVFs. Two patients with sphenobasilar sinus DAVFs reported in the literature have been identified, but they did not simultaneously harbor intracranial meningiomas. To the best of the authors' knowledge, the patient described here is the first case that concomitantly harbors a sphenobasilar sinus DAVF and intracranial meningioma. A 42-year-old man presented with acute subarachnoid hemorrhage. Angiography demonstrated a DAVF of the sphenobasilar sinus with a giant venous aneurysm of the SMCV. After transarterial embolization, the fistula was successfully obliterated and the giant venous aneurysm was resected microsurgically. A fortuitous small meningioma at the anterior clinoid was found and removed during the operation. The patient recovered excellently and resumed his normal activities. The relevant literature is reviewed and discussed.

A phase II clinical trial with cytotropic heterogeneous molecular lipids (CHML) for patients with hepatic malignancies

Hepatocellular carcinoma (HCC) and other forms of metastatic liver cancer (MLC) have poor outcomes due to the limited treatment options. Surgery, radiotherapy and chemotherapy have a limited success. Thus, there is an urgent need for novel therapies for patients with advanced HCC and MLC. The response and toxicity profile of a novel biological anticancer agent, cytotropic heterogeneous molecular lipids (CHML), in 135 Asian patients with hepatic malignancies treated at five different hospitals in China from April 1998 to August 2003 is described. This trial included 97 patients with HCC and 38 with MLC. The majority of these patients had received conventional therapies and many had failed to respond or relapsed. CHML was administered by intra-arterial (i.a.) infusion with or without simultaneous intravenous (i.v.) infusion for 25 days with a rest of 2-4 weeks between each cycle. Fifty three percent of patients received two cycles, and 47% received three cycles. The complete response (CR) rates were 23% for HCC and 29% for MLC with an overall CR of 24%. The overall partial response (PR) was 53%. The patients with earlier stages and limited tumor burden had a better response, but a few patients with advanced disease also achieved PR. The patients who achieved CR or PR had a significant increase in long-term survival for up to five years. The treatment with CHML resulted in minimal toxicity and the reported adverse reactions were not higher than grade II. CHML is an effective therapy for hepatic malignancies, showing responses and increases in survival in patients in whom other therapies have failed. CHML is well tolerated and is an excellent candidate for Phase III clinical trials.

Effect of Nutrition Factors on the Synthesis of Superoxide Dismutase, Catalase, and Membrane Lipid Peroxide Levels in Cordyceps militaris Mycelium

Effect of carbon, nitrogen, and metal ion sources on superoxide dismutase (SOD), catalase (CAT) activities, and lipid perioxide (LPO) levels in Cordyceps militaris mycelium were investigated at stationary growth phase by step supplementing with these nutrition factors in shake-flask cultures. Mycelium was cultivated in several growth media containing different carbon sources. The observed highest SOD and CAT activities were 44.3 U/mg protein in the presence of 20% potato broth plus 2% glucose medium and 93.7 U/mg protein in presence of 20% potato broth plus 1% glucose medium, respectively. By supplementing with either yeast extract or tryptone in 0.1-0.5% concentration range, the highest SOD and CAT activities were 21.1 U/mg protein in medium supplemented with 0.1% yeast extract and 20.7 U/mg protein in medium supplemented with 0.1% tryptone, respectively. Supplementing with Cu(2+), Zn(2+), and Mn(2+) caused a stimulation of SOD synthesis. The minimum LPO level was observed at media presented Zn(2+). The time course of SOD and CAT biosynthesis showed two maxima, which correspond to the maximum of biomass. High SOD levels and low LPO levels in the medium described above indicated that the appropriate metal ions could provide a suitable protection for cells against oxygen radical damage.

Optimizing the error term in direct-method SAD phasing

The probability formula of the direct-method SAD (single-wavelength anomalous diffraction) phasing proposed by Fan & Gu (1985, Acta Cryst. A41, 280-284) contains an error term which is related to the lack-of-closure error. This error term is used as a weighting function in the phase derivation and in the subsequent calculation of electron-density maps. Previously, there has been a constant in the error term that has had to be determined empirically for each particular case. It has been found that improper choice of the constant often leads to failure of the direct-method SAD phasing. The problem is resolved by introducing a modified error term and a method of automatically tuning the associated scaling factor.

Direct-method SAD phasing with partial-structure iteration: towards automation

The probability formula of direct-method SAD (single-wavelength anomalous diffraction) phasing proposed by Fan & Gu (1985, Acta Cryst. A41, 280-284) contains partial-structure information in the form of a Sim-weighting term. Previously, only the substructure of anomalous scatterers has been included in this term. In the case that the subsequent density modification and model building yields only structure fragments, which do not straightforwardly lead to the complete solution, the partial structure can be fed back into the Sim-weighting term of the probability formula in order to strengthen its phasing power and to benefit the subsequent automatic model building. The procedure has been tested with experimental SAD data from two known proteins with copper and sulfur as the anomalous scatterers.

SAD phasing by combination of direct methods with the SOLVE/RESOLVE procedure

In the initial stage of SAD phasing, the essential point is to break the intrinsic phase ambiguity. The presence of two kinds of phase information enables the discrimination of phase doublets from SAD data prior to density modification. One is from the heavy atoms (anomalous scatterers), while the other is from the direct-methods phase relationships. The former can be expressed by the Sim distribution, while the latter can be expressed by the Cochran distribution. Typically, only the Sim distribution has been used to yield initial phases for subsequent density modification. However, it has been demonstrated that using direct-methods phases based on the product of the Sim and Cochran distributions can lead to improved initial phases. In this paper, the direct-methods phasing procedure OASIS has been improved and combined with the SOLVE/RESOLVE procedure. Experimental SAD data from three known proteins with expected Bijvoet ratios </DeltaF/>/<F> in the range 1.4-7.0% were used as test cases. In all cases, the phases obtained using the program RESOLVE beginning with initial phases based on experimental phases plus Sim and direct-methods information were more accurate than those based on experimental plus Sim phase information alone.

Direct-method-aided phasing of MIR diffraction data from proteins

Direct methods have successfully been used to break the phase ambiguity intrinsic in the single isomorphous replacement (SIR) data of proteins. Based on this, the procedure 'direct-method-aided MIR phasing' (DMIR) has been proposed and applied to the four-derivative multiple isomorphous replacement (MIR) data of a known protein containing 682 amino acid residuals in the asymmetric unit. The data set consists of 14,500 unique reflections at 3 A resolution with F(obs.) greater than 2sigma. Test calculation showed that the phases from conventional MIR phasing could be significantly improved by direct methods leading to obvious improvement in the quality of the resultant Fourier maps.

Direct-method-aided phasing of MAD data

The direct methods of breaking the phase ambiguity intrinsic in one-wavelength anomalous scattering (OAS) data and MAD phasing are powerful methods in their own rights. In a different context, in addition to their success in phasing OAS data, direct methods can also be useful in the treatment of MAD data. The idea has been tested with the MAD data at 2.5 A resolution from the protein human adenosine kinase [Mathews et al. (1998), Biochemistry, 37, 15607--15620]. The results showed that the incorporation of direct methods in MAD phasing led to a significant improvement of phases over those obtained from the conventional MAD phasing method alone, as indicated by improved map correlation coefficients (with the existing model), reduced phase errors by 4.5 degrees and improved map connectivity.

Combining direct methods with isomorphous replacement or anomalous scattering data. VIII. Phasing experimental SIR data with the replacing atoms in a centrosymmetric arrangement

A multisolution direct method has been proposed to resolve the phase ambiguity intrinsic in single isomorphous replacement data of proteins with the replacing atoms in a centrosymmetric arrangement. The phase ambiguity of each reflection is in fact a 'sign ambiguity' of the phase difference between the phase of the native protein and that of the replacing atoms, i.e. +/- |Deltatheta| = theta - theta'. The P+ probability formula can be used to derive the signs. The multisolution phasing procedure is initiated using random starting values of P+. A cluster analysis is used instead of figures of merit to find the correct solution. The direct-method phases can be further improved by density-modification techniques. The method was tested with the experimental SIR data at 2 A resolution from a known protein aPP; satisfactory results were obtained.

Use of Single Isomorphous Replacement Data of Proteins – Resolving the Phase Ambiguity and a New Procedure for Phase Extension

A procedure combining direct methods and solvent flattening to break the phase ambiguity intrinsic to the single isomorphous replacement (SIR) technique has been tested with the experimental SIR data of the known protein RNase Sa at 2.5 A resolution. The use of direct methods provided better initial phases for the solvent-flattening procedure, while the solvent-flattening procedure greatly improved direct-method phases leading to a traceable Fourier map. A small subset of known phases at low resolution makes direct phasing of SIR data much easier. Accordingly a method for extending low-resolution phases to high-resolution ones is proposed making use of additional SIR information. This reduces the problem of finding a value in the range of 0-2pi for each unknown phase to that of just making a choice between two possible values. Tests with the known protein RNase Sa showed that the method is able to extend phases from a resolution of 6 to 2.5 A leading to an easily traceable Fourier map. The solvent-flattening technique and the combination of which with direct methods were used for the phase extension. Either procedure yielded reasonably good results, but on the whole, the result from the combination of direct methods with solvent flattening is better. Results of the latter procedure were further compared with that from direct phasing of the 2.5 A SIR data and with that from phase extension by solvent flattening without SIR information. An improvement gained by the use of SIR information is evident.

Direct-space methods in phase extension and phase refinement. V. The histogram moments method

Any distribution is completely defined by its moments. It is shown that a process of phase refinement can be carried out, based on Fourier transforms, which modifies the moments of electron density, separately in the protein and solvent regions, towards target values. Tests have been carried out on two moderate-sized proteins with 800-900 atoms in the asymmetric unit, one containing heavy atoms and the other not. It has been found that refinement using the third moment about zero in the protein region is most effective and that refinement with higher moments, or in the solvent region, adds nothing useful. Two kinds of weights are necessary in the method. One is for giving a weighted mixture of new phase indications with original phase estimates from, say, multiple isomorphous replacement. The other weights are applied to the Fourier coefficients of density maps to give the best possible signal:noise ratio. These weights have been explored empirically and the best ones found are described. It is concluded that since the moments method, which changes phases in reciprocal space, is independent of other histogram-matching procedures, which change density in real space, it has something to offer in a refinement package containing several procedures.

Effects of artemether on peripheral T, B, T mu and T gamma lymphocytes in beagle dog

The effects of intramuscular injection of Artemether on peripheral T, B, T mu and T gamma lymphocytes in beagle dogs was investigated cytochemically. Doses used were 6, 19, and 32 MKD, respectively. Results showed that after injection of Artemether for 15 successive days, the T, B, and T mu lymphocytes of the 19 and 32 MKD groups were markedly reduced and the T gamma lymphocytes of all 3 dosage groups were decreased to zero. 28 days after cessation of the drug, T, T mu and T gamma lymphocytes had recovered to control levels, while the B lymphocytes of the 19 and 32 MKD groups remained markedly lower than those of the control groups. The differences and similarities of the effects on the peripheral T, B, T mu and T gamma lymphocytes produced by the 3 dosages of Artemether and the relationship between the changes of T, B lymphocytes and immunological function of beagle dogs are discussed.

Application of a multilayer decision tree in computer recognition of chinese characters

A multistage classifier with general tree structure has been developed to recognize a large number of Chinese characters. A simple and efficient method of classifying the characters was achieved by choosing the best feature at each stage of the tree. The features used are Walsh coefficients obtained from two profiles of a character projected onto the X-Y orthogonal axes. Some algorithms for aligning the characters were compared and one of them was adopted in this recognition scheme. A high recognition rate of about 99.5 percent was obtained in an experiment with more than 3000 different Chinese characters.