Accurate identification of sludge contamination sources by classification-based PMF and machine learning with consideration of sewer network distribution differences

The application of source identification such as PMF for large-scale pollution source analysis frequently produces ambiguous outcomes. In this study, we utilized a classification-based method to accurately track key pollution sources in the sludge. In the study, we categorized the wastewater treatment plants into two groups: T1 and T2, according to the pipeline network. T1 sewage treatment plants are the main sewage plants in urban areas, covering a large area and connected to industrial wastewater treatment plants for secondary treatment. T2 sewage treatment plants are typically smaller in size and usually responsible for treating sewage in rural or township areas. The PMF analysis indicates that industrial pollution sources contribute 3.4 times more to T1 sludge than to T2 sludge, making industrial pollution the primary factor causing the disparity. The application of Random Forest and Adaboost based on pollutant concentrations for classification and fitting of sludge resulted in the identification of the main pollutants: Zn, Cu, Ni, and Cyanide, which align with characteristic pollutants from the electroplating industry. The GIS analysis shows a significant correlation between the distance of wastewater treatment plants with abnormal environmental risk and electroplating industrial parks, all within a 20 km radius. Indeed, when conducting large-scale pollution source identification studies, utilizing classification-based analysis can effectively improve the accuracy of pollution source identification, leading to more valuable analysis results.

Bioinspired and biomimetic cancer-cell-derived membrane nanovesicles for preclinical tumor-targeted nanotheranostics

Bioinspired cell-membrane-camouflaged nanohybrids have been proposed to enhance tumor targeting by harnessing their immune escape and self-recognition abilities. In this study, we introduce cancer-cell-derived membrane nanovesicles (CCMVs) integrated with gold nanorods (AuVNRs) in addition to therapeutic and imaging cargos such as doxorubicin and indocyanine green. This approach enhances targeted tumor imaging and enables synergistic chemo-phototherapeutics for solid tumors. CCMVs demonstrate significant tumor penetration and retention, serving as nanotheranostics with accessible surface biomarkers, biomimicking properties, and homologous targeting abilities. By evading uptake by the mononuclear phagocytic system, CCMVs can diffuse into the deep tumor core, leading to precise tumor reduction while preserving the surrounding healthy tissues. Notably, intravenous administration of these theranostic agents ensures biocompatibility, as evidenced by a survival period of approximately two months (up to 63 days) without any observed side effects. Our findings underscore the diagnostic and therapeutic potential of this biomimetic nanotheranostics platform.

Complete lumbarization with calcified disc herniations at L5S1 and S1-2 levels treated with percutaneous endoscopic interlaminar discectomy: a case report and technique note

Objective

This study aims to report a case of a patient with complete lumbarization (Castellvi-IB) who developed symptomatic calcified disc herniations at L5S1 and lumbarized S1-2 levels and achieved excellent neurological recovery following percutaneous endoscopic interlaminar discectomy (PEID).

Summary of Background Data

In 1984, Castellvi et al. classified lumbosacral transitional vertebra (LSTV) into four types. They incorrectly classified I LSTV anomalies as only type I sacralization, not realizing type I lumbarization also belonged to type I LSTV, with the latter exhibiting a well-developed S1-2 disc (lumbosacral transitional disc, LSTD). Patients with type I lumbarization rarely develop calcified disc herniations concomitantly at L5S1 and LSTD levels. PEID has been developed to perform discectomy for neurological decompression at the lumbar region, especially at the lowest level where the higher iliac crest and/or widened transverse process exists.

Methods

A 47-year-old male presented to our hospital complaining of an intractable left leg radiating pain for 3 weeks after suffering from chronic radiating pain for 4 years. His physical examination found hyperalgesia at the lateral side of the left calf, decreased dorsal flexion strength of the ankle (grade 4/5), and a positive sign of straight leg raising test at the left side (30°). The preoperational Lumbar JOA (Japanese Orthopaedic Association) score was 12. Image examinations including whole spinal radiograph, MRI, and CT confirmed complete lumbarization (Castellvi-IB) with calcified disc herniations at L5S1 and LSTD levels at the left side. PEID was carried out at two index levels to accomplish decompression via the left approach.

Results

The patient's neurological function recovered quickly. One day postoperatively, he began to walk without discomfort. After 3 months, his muscle strength recovered to normal, and after 6 months, the residual dysesthesia at his posterolateral calf disappeared. The follow-up Lumbar JOA score was 26.

Conclusion

Calcified lumbar disc herniation could develop at two distal levels concomitantly in the case of type I complete lumbarization. This anomaly might be misinterpreted as a normal lumbar sequence by only lumbar MRI. PEID may be an effective procedure to treat such calcified disc herniations in a single visit.

Successful treatment of thoracic myelopathy caused by spontaneous spinal epidural hematoma (SSEH) combined with calcification of the ligamentum flavum (CLF) by posterior percutaneous endoscopic surgery (PPES): A case report

Study Design

A retrospective case report.

Objective

To report a case who developed deteriorated paraplegia by spontaneous spinal epidural hematoma (SSEH) based on calcification of the ligamentum flavum (CLF) at the T10-11 level, achieved full neurological recovery following posterior percutaneous endoscopic surgery (PPES).

Summary of Background Data

CLF rarely occurs at the thoracic spine, and the symptom usually progress slowly. SSEH is another rare spinal lesion that might progress rapidly and cause emergent severe spinal cord compression syndrome. Coexistence of SSEH and CLF at the same thoracic level was rarely reported in English literature.

Methods

A 65-year-old man presented to our hospital with the complaint of sensorimotor loss on the lower limbs and dysfunction of bladder for 1 day after a progressive weakness and numbness of the lower limbs for 3 months. MR examination found a dorsal protruding mass at the T10-11 level, while computed tomography (CT) found the protruding mass contained scattered calcified deposits. The patient was diagnosed with thoracic CLF. Decompression via PPES was carried out to realize bilateral decompression through a unilateral approach.

Results

During the operation, the protruding mass was found to be composed of SSEH and CLF together. After the operation, the patient's neurological function recovered quickly. One week later, the patient could walk by himself. After 3 months, complete neurological function had recovered.

Conclusion

SSEH could develop based on CLF at thoracic level and cause serious neurological dysfunction. PPES might be an advisable method to remove CLF and evacuate SSEH with good clinical results.

Establishing an integrated prevention and control system to ensure zero nosocomial infections - an analysis of the logistics support in controlling nosocomial infections during the hospital's fight against the COVID-19 epidemic

AIM

To analyze the role of the logistics support services in nosocomial infection control during emergency periods, with a focus on job responsibilities including the organization of vehicle parking, supply of hospital meals, washing of medical bedding and clothing, disposal and management of medical sewage and waste, elevator services, disinfection of air conditioning systems, disinfection and cleaning of ambulances, management of hospital buildings, storage of sterilization supplies, reception and delivery of oxygen cylinders and protection of staff health as examples.

METHODS

The adjustment and optimization of the emergency support system and working mode as part of hospitals' response to major public emergencies were summarized, and the vital supporting role of the logistics support services in nosocomial infection control was analyzed.

RESULTS

The logistics support services played a crucial role in ensuring the high-performance operations of the hospitals and control of nosocomial infections, resulting in the excellent outcome of "zero infection" among hospital staff.

CONCLUSION

Establishing a safe, flexible and efficient system for the logistics support services is important in ensuring an effective response by hospitals to health emergencies.

Association between hematocrit and the 30-day mortality of patients with sepsis: A retrospective analysis based on the large-scale clinical database MIMIC-IV

This research sought to ascertain the relationship between hematocrit (HCT) and mortality in patients with sepsis. Methods: A retrospective analysis was conducted on the clinical data of septic patients who were hospitalized between 2008 and 2019 in an advanced academic medical center in Boston, Massachusetts, registered in the Medical Information Mart for Intensive Care IV (MIMIC-IV) database, We analyzed basic information including gender, age, race, and types of the first admission, laboratory indicators including HCT, platelets, white blood cells, albumin, bilirubin, hemoglobin, and serum creatinine, and 30-day mortality. A Cox proportional hazards regression model was utilized to analyze the relationship between HCT and 30-day mortality in patients with sepsis. Results: This research recruited 2057 patients who met the research requirements from 2008 to 2019. According to the HCT level, it was classified into the low HCT level, the regular HCT level, and the high HCT level. The 30-day mortality rate was 62.6%, 27.5%, and 9.9% for patients with the low HCT level, the regular HCT level, and the high HCT level, respectively (p < 0.05). The multivariate Cox proportional hazard regression model analysis displayed that compared with patients with the regular HCT level, the 30-day mortality of patients with the low HCT level increased by 58.9% (hazard ratio = 1.589, 95% confidence interval (CI) = 1.009–2.979, p < 0.05). Conclusion: The low HCT level is an independent risk factor for the increase of the 30-day mortality in patients with sepsis and can be used as a significant predictor of the clinical outcome of sepsis.

Cloning and expression analysis of PRL and PRLR genes in black Muscovy duck

1. Prolactin hormone (governed by the PRL gene) is secreted by the anterior pituitary of animals, which combines with its receptor (prolactin receptor, PRLR) to act on target cells. Both PRL and PRLR are mainly associated with reproductive performance. The genetic mechanism of nesting in poultry is not yet clear, and so the aim of the current study was to determine expression patterns of PRL and PRLR at different times across the breeding stages of black Muscovy ducks.2. In this study, the CDS regions of PRL and PRLR were determined by RACE sequencing. The expression levels of PRL and PRLR in the pituitary, ovary and uterus from the black Muscovy duck were compared and analysed during the pre-laying, laying and nesting periods.3. The results showed that PRL and PRLR are highly homologous in a variety of poultry species. The expression of the PRL gene in the pituitary was the highest, which was significantly higher than seen in the ovary and uterus. This trend ran through the entire prenatal period, i.e. the laying period and the nesting period. The expression level of the PRLR gene in the pituitary and ovary was generally low, and expression in the uterus was the highest. There was no significant difference in expression of the PRLR gene between pituitary and ovary during different periods, but the expression level of the PRLR gene in the uterus reached its highest level during the nesting stage, which was significantly higher than seen in the early laying period.

[Prosthodontic specialty training in the United States: what can we learn]

Prosthodontics is one of the nine recognized specialties by American Dental Association. The postgraduate prosthodontic program used to train prosthodontic specialists in U S A started about 70 years ago. Compared to China which just launched the dental residency programs, the programs in U S A have more developed and relatively more mature education system. It is worthwhile for China to study and learn the U S A prosthodontic residency education program. Prosthodontics is a specialty to diagnose and treat complex dental problems, and is often considered as the 'orchestrator' directing and coordinating all the other dental specialists to manage complex situations. This specialty plays an important role in a nation's oral health system. The present article is aimed to introduce the history of US prosthodontic residency program, initial accreditation, curriculum, education standards and mechanisms of the residency program, and how the program is monitored and managed post initial accreditation, with the hope that this system can serve as a reference for China's developing its own residency program.

SMARCB1 is required for widespread BAF complex-mediated activation of enhancers and bivalent promoters

Perturbations to mammalian SWI/SNF (BAF) complexes contribute to over 20% of human cancers, with driving roles first identified in malignant rhabdoid tumor (MRT), an aggressive pediatric cancer characterized by biallelic inactivation of the core BAF complex subunit SMARCB1 (BAF47). However, the mechanism by which this alteration contributes to tumorigenesis remains poorly understood. We find that BAF47 loss destabilizes BAF complexes on chromatin, absent significant changes in intra-complex integrity. Rescue of BAF47 in BAF47-deficient sarcoma cell lines results in increased genome-wide BAF complex occupancy, facilitating widespread enhancer activation and opposition of polycomb-mediated repression at bivalent promoters. We demonstrate differential regulation by BAF and PBAF complexes at enhancers and promoters, respectively, suggesting distinct functions of each complex which are perturbed upon BAF47 loss. Our results demonstrate collaborative mechanisms of mSWI/SNF-mediated gene activation, identifying functions that are coopted or abated to drive human cancers and developmental disorders.

Human bone morphogenetic protein 7 transfected nucleus pulposus cells delay the degeneration of intervertebral disc in dogs

The main reason for intervertebral disc (IVD) degeneration is the decrease in the quantity and activity of IVD cells with subsequent reduction of the extracellular matrix (ECM). In this study, we investigated a cell-based repair strategy by injecting nucleus pulposus cells (NPCs) transduced with human bone morphogenetic protein (hBMP7) by adeno-associated virus-2 into the canine degenerative IVD to determine whether NPCs expressing hBMP7 could delay the degeneration of the IVD. Fourteen canines received annular punctures to induce disc degeneration. Eight weeks later, saline (group A), allogeneic NPCs (group B), or allogeneic NPCs transduced with hBMP7 (group C) were injected into the degenerative discs. Twelve weeks after the injection, MRI scan showed that the degeneration process of groups C was slower and less severe compared with that of groups B and C. The IVD stability in group C was superior to that in groups A and B in left-right bending and rotation. HE, safranin-O staining, and ELISA indicated that the degenerative degree of the IVD in group C was significantly milder than that in groups A and B. The study demonstrated that the implantation of NPCs-hBMP7 could effectively maintained the structural integrity, ECM, and biomechanical properties of the canine degenerated discs. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1311-1322, 2017.

Analysis of the genetic diversity of Lonicera japonica Thumb. using inter-simple sequence repeat markers

Inter-simple sequence repeats (ISSRs) were used to analyze the genetic diversity of 21 accessions obtained from four provinces in China, Shandong, Henan, Hebei, and Sichuan. A total of 272 scored bands were generated using the eight primers previously screened across 21 accessions, of which 267 were polymorphic (98.16%). Genetic similarity coefficients varied from 0.4816 to 0.9118, with an average of 0.6337. The UPGMA dendrogram grouped 21 accessions into two main clusters. Cluster A comprised four Lonicera macranthoides Hand. Mazz. accessions, of which J10 was found to be from Sichuan, and J17, J18, and J19 were found to be from Shandong. Cluster B comprised 17 Lonicera japonica Thumb. accessions, divided into the wild accession J16 and the other 16 cultivars. The results of the principal component analysis were comparable to the cluster analysis. Therefore, the ISSR markers could be effectively used to distinguish interspecific and intraspecific variations, which may facilitate identification of Lonicera japonica cultivars for planting, medicinal use, and germplasm conservation.

The Effects of Aerobic Exercise on Cognitive Function of Alzheimer's Disease Patients

To evaluate the effect of moderate intensity of aerobic exercise on elderly people with mild Alzheimer's disease, we recruited fifty volunteers aged 50 years to 80 years with cognitive impairment. They were randomized into two groups: aerobic group (n=25) or control group (n=25). The aerobic group was treated with cycling training at 70% of maximal intensity for 40 min/d, 3 d/wk for 3 months. The control group was only treated with heath education. Both groups were received cognitive evaluation, laboratory examination before and after 3 months. The results showed that the Minimum Mental State Examination score, Quality of Life Alzheimer's Disease score and the plasma Apo-a1 level was significantly increased (P<0.05), the Alzheimer's Disease Assessment Scale-cognition score, Neuropsychiatric Inventory Questionnaire score was significantly decreased.(P<0.05) in aerobic group before and after 3 months in aerobic group. For the control group, there was no significant difference in scores of Alzheimer's Disease Assessment Scale-cognition, Neuropsychiatric Inventory Questionnaire, Quality of Life Alzheimer's Disease, Apo-a1 (P>0.05), while Minimum Mental State Examination scores decreased significantly after 3 months (P<0.05). In conclusion, moderate intensity of aerobic exercise can improve cognitive function in patients with mild Alzheimer's disease.

Association Between KCNJ11 Gene E23K Polymorphism and Body Composition Together with its Response to Endurance Training

Objective:

To explore the Association between KCNJ11 gene E23K polymorphism of Chinese and body composition together with its response to endurance training. Method: 102 biologically unrelated Han nationality male new recruits from northern China volunteered to execute a 5000-m running programme, and the intensity is 95–105% individual lactate threshold. The protocol was lasted for 18 weeks, three times per week. The body composition index, including body weight (WT)、lean body weight (LBW), body mass index (BMI) and body fat percentage (Fat%), was measured before and after training. PCR-RFLP was used to detect the KCNJ11 gene E23K polymorphism.

Results:

Hardy-Weinberg equilibrium was observed for the frequency of genotypes in these subjects. Before training, WT, BMI and Fat% in KK group were significantly higher than those in EE and KK group (p<0.05 or p<0.01). There was no significant difference in LBW among groups (P>0.05). After training, the changes of all body composition index in KK group were bigger significantly greater than those in EE and EK groups (p<0.01).

Conclusion:

KCNJ11 gene E23K polymorphism might contribute to individual body composition together with its response to endurance training. The body fat content at baseline in KK was more than those in EE and EK groups, and it may hinder that individual to eliminate their body fat during endurance training.

Transcriptome analysis of glioma cells for the dynamic response to γ-irradiation and dual regulation of apoptosis genes: a new insight into radiotherapy for glioblastomas

Ionizing radiation (IR) is of clinical importance for glioblastoma therapy; however, the recurrence of glioma characterized by radiation resistance remains a therapeutic challenge. Research on irradiation-induced transcription in glioblastomas can contribute to the understanding of radioresistance mechanisms. In this study, by using the total mRNA sequencing (RNA-seq) analysis, we assayed the global gene expression in a human glioma cell line U251 MG at various time points after exposure to a growth arrest dose of γ-rays. We identified 1656 genes with obvious changes at the transcriptional level in response to irradiation, and these genes were dynamically enriched in various biological processes or pathways, including cell cycle arrest, DNA replication, DNA repair and apoptosis. Interestingly, the results showed that cell death was not induced even many proapoptotic molecules, including death receptor 5 (DR5) and caspases were activated after radiation. The RNA-seq data analysis further revealed that both proapoptosis and antiapoptosis genes were affected by irradiation. Namely, most proapoptosis genes were early continually responsive, whereas antiapoptosis genes were responsive at later stages. Moreover, HMGB1, HMGB2 and TOP2A involved in the positive regulation of DNA fragmentation during apoptosis showed early continual downregulation due to irradiation. Furthermore, targeting of the TRAIL/DR5 pathway after irradiation led to significant apoptotic cell death, accompanied by the recovered gene expression of HMGB1, HMGB2 and TOP2A. Taken together, these results revealed that inactivation of proapoptotic signaling molecules in the nucleus and late activation of antiapoptotic genes may contribute to the radioresistance of gliomas. Overall, this study provided novel insights into not only the underlying mechanisms of radioresistance in glioblastomas but also the screening of multiple targets for radiotherapy.

Nucleus pulposus cells expressing hBMP7 can prevent the degeneration of allogenic IVD in a canine transplantation model

We have previously explored the possibilities of allogenic intervertebral disc (IVD) curing disc degeneration disease in clinical practice. The results showed that the motion and stability of the spinal unit was preserved after transplantation of allogenic IVD in human beings at 5-year follow-up. However, mild degeneration was observed in the allogenic transplanted IVD cases. In this study, we construct the biological tissue engineering IVD by injecting the nucleus pulposus cells (NPCs) expressing human bone morphogenetic protein 7 (hBMP7) into cryopreserved IVD, and transplant the biological tissue engineering IVD into a beagle dog to investigate whether NPCs expressing hBMP7 could prevent the degeneration of the transplanted allogenic IVDs. At 24 weeks after transplantation, MRI scan showed that IVD allografts injected NPCs expressing hBMP7 have a slighter signs of degeneration than IVD allografts with NPCs or without NPCs. The range of motion of left-right rotation in the group without NPCs was bigger than that of two cells injection group. PKH-26-labeled cells were identified at IVD allograft. The study demonstrated that NPCs expressing hBMP7 could survive at least 24 weeks and prevent the degeneration of the transplanted IVD. This solution might have a potential role in preventing the IVD allograft degeneration in long time follow-up.

The effect of two different counting methods on the quality of CPR on a manikin--a randomized controlled trial

OBJECTIVES

To compare the quality of cardiopulmonary resuscitation (CPR) and rescuers' exhaustion using different methods of counting, and to establish an appropriate method of counting.

MATERIALS AND METHODS

Forty-eight subjects who had received formal training in basic life support (BLS) were recruited from doctors and nurses working in the Emergency Department of a university hospital. They performed 3 min of continuous chest compressions using two different methods of counting, one after the other, on an adult resuscitation manikin. The total number of compressions, the number of these considered satisfactory, the peak heart rate of subjects and the time to peak heart rate were all recorded. Perceived fatigue and discomfort was evaluated by self-reported survey results with use of a visual analogue scale (VAS).

RESULTS

The effective power of external chest compression and the mean compression depth when counting from 1 to 10, repeated three times, were greater than those achieved when counting from 1 to 30 during 3 min of CPR (67.48% vs. 57.81% and 44.52 mm vs. 40.48 mm, P<0.05). The exhaustion-score using the VAS (22.15 points) was lower and the time to peak heart rate (124.88 s) was longer when counting from 1 to 10, repeated three times, than when rescuers counted from 1 to 30.

CONCLUSIONS

Counting from 1 to 10 three times in Chinese as opposed to 1-30 results in better quality chest compressions. Counting from 1 to 10 three times was associated with less user feelings of fatigue, and a longer time to peak heart rate. These findings support the teaching of counting compressions 1-10 three times during CPR.

Establishment of an animal model of biliary ischemic stenosis with clamping in mice

OBJECTIVE

The objective of this study was to explore a method to establish biliary ischemic stenosis in mice.

METHODS

After the optimal time of biliary ischemia was determined, 20 Kunming mice were equally divided into 2 groups. In the experimental group a 0.4-cm length of common bile duct was clamped for 90 minutes with 2 micro-vessel clamps (width = 0.1 cm). The common bile duct was not clamped in the control group. Twenty-one days later, biliary tract visualization was performed in all mice. Blood samples were collected from the inferior vena cava to determine the serum levels of total bilirubin (TBIL) and alanine aminotransferase (ALT). Meanwhile, samples of the common bile duct and liver tissue were extracted for microscopic examination to observe morphological changes.

RESULTS

In the experimental group, obvious dilatation of the common bile duct appeared over the clamp site. There was no dilatation of the common bile duct in the control group. Twenty-one days later, serum levels of TBIL and ALT were significantly higher among the experimental compared with the control group. Microscopic examination showed that the part of common bile duct at the clamp site was significantly expanded, with a smaller or occluded bile duct lumen necrotic mucosa with determination, and tubular wall with fibrosis and excrustation. A few dead liver cells and many inflammatory cells were observed in liver tissue samples.

CONCLUSIONS

A biliary ischemic stenosis model was established using a clamping method in mice, which may provide a reliable technique for basic and clinical research into mechanisms of biliary ischemic stenosis after liver transplantation.

Clematis huchouensis TAMURA: A Traditional Chinese Herbal Medicine and Its Quality Control Using a High Performance Liquid Chromatography Technique

A simple, specific and reliable high performance liquid chromatography (HPLC) method has been developed and validated for study of fingerprint chromatograms of extracts from the whole plant of Clematis huchouensis Tamura (CHT) for quality control of a traditional Chinese medicinal (TCM) herb. An Agilent C18 column was used to separate extracts in this protocol and detection was made by ultraviolet absorbance at 340 nm. The column temperature was maintained at 25 degrees C. A mobile phase consisting of (a) water (with 30 mM KH2PO4) and (b) CH3CN, (c) CH3OH was found to be suitable for this separation at a flow rate of 0.8 microl min(-1) with gradient elution. Under the described conditions, a fingerprint profile of 8 compounds was collected within 35 min, which made the HPLC method unique and interesting. The fingerprint chromatograms had good stability, precision and reproducibility. Moreover, eco-climatic (habitat) effects were studied by comparison of fingerprint chromatograms obtained from extracts of CHT collected from two habitats, with rutin as a reference marker peak. The protocol developed is quite suitable for differentiation of extracts of CHT and can be used as a quality control method for this herb and a model for other herbal drugs.

Oxidative stress potentiates BACE1 gene expression and Abeta generation

Alzheimer's Disease (AD) is the most common neurodegenerative disorder leading to dementia and its prevalence increases with age. The pathological features of AD are characterized by the beta-amyloid protein (A(beta)) deposits in the core of neuritic plaques and abnormal neurofibrillary tangles in the brain of AD patients. BACE1 is the major beta-secretase to cleave the beta-amyloid precursor protein (APP) to generate A(beta). Oxidative stress has been shown to affect A(beta) generation in the AD pathogenesis and the mechanism of such effect is unknown. In this report we generated a novel promoterless enhanced green fluorescent protein (EGFP) reporter gene cloning vector and cloned a 1.9-kb BACE1 gene promoter fragment in this vector. The BACE1 promoter fragment can efficiently activate EGFP or luciferase gene transcription. Oxidative stress induced by hydrogen peroxide resulted in significant increase in the BACE1 promoter activity. Furthermore, hydrogen peroxide treatment facilitated beta-secretase activity and A(beta) generation. Thus, upregulation of BACE1 transcription by oxidative stress may contribute to the pathogenesis of Alzheimer's disease.

[A new algorithm for displaying the cutting isosurface of structures]

The existing algorithms for displaying the cutting isosurface of the structure are not suitable for interactive display because they spend too much time on calculation when a fair amount of data is submitted to processing. This paper presents a new algorithm for accelerating the cutting of structure by using the area partition and the increment calculation to reduce the unnecessary calculation in cutting the structure. It is suitable for real time interactive displaying, especially in the case of a vast amount of data.

Regeneration of N, P and Si near the sediment/water interface of lakes from Southwestern China Plateau

Lake water, pore water, and sediments were sampled in both polluted and unpolluted lakes from Southwestern (SW) China Plateau. The results show that although the mechanisms of nutrient regeneration were similar in the polluted and unpolluted lakes, the processes, however, were much stronger in the polluted lakes. Nitrogen regeneration was mainly of organic process. Phosphorus regeneration was essentially controlled by iron redox cycling near sediment/water interface. Nutrient upward fluxes were in the order SiO2 > NH4+ > PO4(3-). This study has significance for further investigating the response of nutrient biogeochemistry to the increasing nutrient levels in aquatic environments.

[Multi-resolution blending rendering of the medical structure]

This paper presents a new medical data visualization method called multi-resolution blending rendering which has been developed for visualizing the large medical volume data sets. Different from those multi-resolution rendering methods which simplify the structures by polygon mesh optimization technique, the new method uses different resolution levels to represent different parts of a structure at the same time. So, it can preserve the integrality of the structure and emphasize the important part of the structure when simplifying the structure. The new method also takes advantage of the good qualities of the wavelet transform and constructs the multi-resolution blending model of the structure by orthogonal wavelet transform and transition operator. The experiment proves that our method can effectively simplify the model of the structure, enormously reduce the number of the triangle of the structure and speed up the structure rendering. It is especially suitable for interactive observations on a complex medical structure.

A deoxyinosine specific endonuclease from hyperthermophile, Archaeoglobus fulgidus: a homolog of Escherichia coli endonuclease V

Deoxyadenosine undergoes spontaneous deamination to deoxyinosine in DNA. Based on amino acids sequence homology, putative homologs of endonuclease V were identified in several organisms including archaebacteria, eubacteria as well as eukaryotes. The translated amino acid sequence of the Archaeoglobus fulgidus nfi gene shows 39% identity and 55% similarity to the E. coli nfi gene. A. fulgidus endonuclease V was cloned and expressed in E. coli as a C-terminal hexa-histidine fusion protein. The C-terminal fusion protein was purified to apparent homogeneity by a combination of Ni(++) affinity and MonoS cation exchange liquid chromatography. The purified C-terminal fusion protein has a molecular weight of about 25kDa and showed endonuclease activity towards DNA containing deoxyinosine. A. fulgidus endonuclease V has an absolute requirement for Mg(2+) and an optimum reaction temperature at 85 degrees C. However, in contrast to E. coli endonuclease V, which has a wide substrate spectrum, endonuclease V from A. fulgidus recognized only deoxyinosine. These data suggest that the deoxyinosine cleavage activity is a primordial activity of endonuclease V and that multiple enzymatic activities of E. coli endonuclease V were acquired later during evolution.

Deoxyxanthosine in DNA is repaired by Escherichia coli endonuclease V

Deoxycytidine, deoxyadenosine and deoxyguanosine undergo spontaneous deamination to form deoxyuridine, deoxyinosine and deoxyxanthosine, respectively. In this manuscript, we show that in addition to its known ability to recognize deoxyuridine and deoxyinosine in DNA, Escherichia coli endonuclease V cleaves DNA containing deoxyxanthosine. However, Alk A protein and human methylpurine glycosylase are unable to recognize deoxyxanthosine. Endonuclease V cleaves DNA containing deoxyxanthosine at the second phosphodiester bond 3' to deoxyxanthosine, generating a 3'-hydroxyl and a 5'-phosphoryl group at the nick site. This endonucleolytic activity requires Mg(2+) or Mn(2+), and is highly specific for double stranded DNA. Endonuclease V-catalyzed cleavage of DNA containing deoxyxanthosine is a result of its ability to recognize the altered base and not due to its mismatch-specific endonuclease activity. The ability of endonuclease V to recognize both deoxyinosine and deoxyxanthosine suggests that endonuclease V is important for preventing mutations that might arise as a result of deamination of purines.

[Influence of functional groups of huatanyuxin decoction on Ca2+ transmembrane influx in rat aorta]

OBJECTIVE

To study the Ca2+ antagonistic effect of functional groups of Huatanyuxin decoction.

METHOD

The 45Ca transmembrane influx technique was used to measure the Ca2+ blocking effect of leak, receptor-operated Ca2+ channel (ROC) and potential-dependent Ca2+ channel (PDC) in rat aorta.

RESULT

ROC and PDC could be blocked when the complex prescription was used at concentrations of 0.5-5 mg/ml. Among the functional groups, Huoxue group (activating blood) and Xinqi group (promoting and normalizing flow of vital energy) showed better Ca2+ antagonistic effect.

CONCLUSION

The mechanism of therapeutic effect of Huatanyuxin decoction may be related to its Ca2+ blocking effect similar to verapamil.

Chu Cheng and Chu's bequeathed book

Chu Cheng, a native of Yangzhai county in Henan Province, was born in the Nanqi Dynasty. His "Chu's Bequeathed Book" has more than 2200 Chinese characters, was divided into ten verses, reflecting the secrets of Qi-Blood-Yin-Yang. This author tries to introduce and study Chu Cheng's life, his story and his academic views, not only on embryogensis, pulse taking and Five Ti, but also on Yin-Ying-Jing-Xue, obstetrical hygiene and infectious disease and the usage of medicine, etc.

Structural study on hen egg-white lysozyme crystals grown in gravity and microgravity

Microgravity in space offers an ideal environment for growing protein crystals, where there is an absence of density-driven convection and sedimentation. Using domestic apparatus of protein crystalizetion, two space experiments of protein crystal growth have been carried out on the Chinese re-entry satellite, and good-quality hen egg-white lysozyme crystals were obtained. To study the effect of microgravity on the prorein crystal structure, three structures of lysozyme crystals grown in gravity and microgravity were determined at high resolution.

Biodistribution of [64Cu]Cu2+ and variance of metallothionein during tumor treatment by copper

The kinetic distribution patterns of [64Cu]Cu2+ in normal mice and in mice bearing tumors (HepA, ascitic tumor) after i.v. injection were similar. The i.v. injected [64Cu]Cu2+ concentrated into mouse liver first and then went to other organs and tissues, such as kidney and tumor. Most of the [64Cu]Cu2+ injected concentrated into the liver within 4 h, and about 8% of the total [64Cu]Cu2+ injected concentrated into the tumor cells at 24 h after i.v. injection. About 80% and 90% of the soluble [64Cu]Cu in the livers of tumor-bearing mice and normal mice, respectively, existed as [64Cu]CuMT (metallothionein [MT] is a small protein with many cysteine residues) at 4 h after i.v. injection, while about 43% of the soluble [64Cu]Cu2+ in tumor cells combined with MT at 6 h after i.v. injection. After 10 days oral administration of 150 microg/g body weight copper acetate, the concentration of MT in tumor cells reduced sharply, from 316 microg/g tissue to 152 microg/g tissue, while it increased slightly, from 375 microg/g tissue to 439 microg/g tissue, in the livers of tumor-bearing mice (HepA, solid tumor). The results suggest that MT contributes to the metabolism of copper that is localized mainly in the liver after copper administration and that copper can concentrate into mouse tumor cells followed by the reduction of MT in tumor cells.