Influence of the community assemblage on sulfur distributions in the South China sea

Marine distribution of dimethylsulfoniopropionate (DMSP) and its cleavage product dimethyl sulfide (DMS) is greatly affected by the community structures of bacteria, phytoplankton, and zooplankton. Spatial distributions of dissolved and particulate DMSP (DMSPd,p), and DMS were measured and their relationships with DMSP lyase activity (DLA), abundance of DMSP-consuming bacteria (DCB), and the community structures of phytoplankton, zooplankton, and bacteria were determined during summer in the South China Sea (SCS). The depth distributions of DMSPd,p exhibited a similar trend with Chl a, reaching their maxima in the mixing layer. The DMS concentration was positively correlated with DCB abundance and DLA, indicating that DCB and DMSP lyase had a significant effect on DMS production. High DMS concentrations in the horizontal distribution coincided with high DCB abundance and DLA and may be due to the rapid growth of phytoplankton resulting from the high dissolved inorganic nitrogen concentration brought by the cold vortices. Moreover, the highest copepod abundance at station G3 coincided with the highest DMS concentrations there among stations B4, F2, and G3. These results suggest that copepod may play an important role in DMS production. The bacterial SAR11 clade was positively correlated with DLA, indicating its significant contribution to DMSP degradation in the SCS. These findings contribute to the understanding of the effect of the community assemblage on DMSP/DMS distributions in the SCS dominated by mesoscale vortices.

Effects of nanoplastics exposure on ingestion, life history traits, and dimethyl sulfide production in rotifer Brachionus plicatilis

Microplastics (MPs) and nanoplastics (NPs) have gained global concern due to their detrimental effects on marine organisms. We investigated the effects of 80 nm polystyrene (PS) NPs on life history traits, ingestion, and dimethyl sulfide (DMS) and dimethylsulfoniopropionate (DMSP) production in the rotifer Brachionus plicatilis. Fluorescently labeled 80 nm PS NPs were ingested by the rotifer B. plicatilis and accumulated in the digestive tract. The lethal rates of B. plicatilis exposed to NPs were dose-dependent. High concentrations of PS NPs exposure had negative effects on developmental duration, leading to prolonged embryonic development and pre-reproductive periods, shortened reproductive period, post-reproductive period, and lifespan in B. plicatilis. High concentrations of PS NPs exposure inhibited life table demographic parameters such as age-specific survivorship and fecundity, generation time, net reproductive rate, and life expectancy. Consequently, the population of B. plicatilis was adversely impacted. Furthermore, exposure to PS NPs resulted in a reduced ingestion rate in B. plicatilis, as well as a decreased in DMS, particulate DMSP (DMSPp) concentration, and DMSP lyase activity (DLA), which exhibited a dose-response relationship. B. plicatilis grazing promoted DLA and therefore increased DMS production. PS NPs exposure caused a decline in the increased DMS induced by rotifer grazing. Our results help to understand the ecotoxicity of NPs on rotifer and their impact on the biogeochemical cycle of dimethylated sulfur compounds.

[Population structure of food-borne Staphylococcus aureus in China]

Objective: To understand the population structure of food-borne Staphylococcus (S.) aureus in China. Methods: Whole genome sequencing was used to analyze 763 food-borne S. aureus strains from 16 provinces in China from 2006 to 2020. Multilocus sequence typing (MLST), staphylococcal protein A gene (spa) typing, and staphylococcal chromosome cassettemec (SCCmec) typing were conducted, and minimum spanning tree based on ST types (STs) was constructed by BioNumerics 7.5 software. Thirty-one S. aureus strains isolated from imported food products were also included in constructing the genome phylogenetic tree. Results: A total of 90 STs (20 novel types) and 160 spa types were detected in the 763 S. aureus isolates. The 72 STs (72/90, 80.0%) were related to 22 clone complexes. The predominant clone complexes were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, accounting for 82.44% (629/763) of the total. The STs and spa types in the predominant clone complexes changed over the years. The methicillin-resistant S. aureus (MRSA) detection rate was 7.60%, and 7 SCCmec types were identified. The ST59-t437-Ⅳa (17.24%, 10/58), ST239-t030-Ⅲ (12.07%, 7/58), ST59-t437-Ⅴb (8.62%, 5/58), ST338-t437-Ⅴb (6.90%, 4/58) and ST338-t441-Ⅴb (6.90%, 4/58) were the main types in MRSA strains. The genome phylogenetic tree had two clades, and the strains with the same CC, ST, and spa types clustered together. All CC7 methicillin sensitive S. aureus strains were included in Clade1, while 21 clone complexes and all MRSA strains were in Clade2. The MRSA strains clustered according to the SCCmec and STs. The strains from imported food products in CC398, CC7, CC30, CC12, and CC188 had far distances from Chinese strains in the tree. Conclusions: In this study, the predominant clone complexes of food-borne strains were CC7, CC1, CC5, CC398, CC188, CC59, CC6, CC88, CC15, and CC25, which overlapped with the previously reported clone complexes of hospital and community-associated strains in China, suggesting that close attention needs to be paid to food, a vehicle of pathogen transmission in community and food poisoning.

[Study of the urban-impact on microbial communities and their virulence factors and antibiotic resistance genomes in the Nandu River, Haikou]

Objective: To explore the changes in bacterial community structure, antibiotic resistance genome, and pathogen virulence genome in river water before and after the river flowing through Haikou City and their transmission and dispersal patterns and to reveal anthropogenic disturbance's effects on microorganisms and resistance genes in the aquatic environment. Methods: The Nandu River was divided into three study areas: the front, middle and rear sections from the upstream before it flowed through Haikou City to the estuary. Three sampling sites were selected in each area, and six copies of the sample were collected in parallel at each site and mixed for 3 L per sample. Microbial community structure, antibiotic resistance, virulence factors, and mobile genetic elements were analyzed through bioinformatic data obtained by metagenomic sequencing and full-length sequencing of 16S rRNA genes. Variations in the distribution of bacterial communities between samples and correlation of transmission patterns were analyzed by principal co-ordinates analysis, procrustes analysis, and Mantel test. Results: As the river flowed through Haikou City, microbes' alpha diversity gradually decreased. Among them, Proteobacteria dominates in the bacterial community in the front, middle, and rear sections, and the relative abundance of Proteobacteria in the middle and rear sections was higher than that in the front segment. The diversity and abundance of antibiotic resistance genes, virulence factors, and mobile genetic elements were all at low levels in the front section and all increased significantly after flow through Haikou City. At the same time, horizontal transmission mediated by mobile genetic elements played a more significant role in the spread of antibiotic-resistance genes and virulence factors. Conclusions: Urbanization significantly impacts river bacteria and the resistance genes, virulence factors, and mobile genetic elements they carry. The Nandu River in Haikou flows through the city, receiving antibiotic-resistant and pathogen-associated bacteria excreted by the population. In contrast, antibiotic-resistant genes and virulence factors are enriched in bacteria, which indicates a threat to environmental health and public health. Comparison of river microbiomes and antibiotic resistance genomes before and after flow through cities is a valuable early warning indicator for monitoring the spread of antibiotic resistance.

[Establishment and evaluation of a method for phages enrichment by ferric trichloride-polyvinylidene fluoride membrane filter]

Objective: To establish and evaluate a method of enriching bacteriophages in natural water based on ferric trichloride-polyvinylidene fluoride (FeCl₃-PVDF)membrane filter. Methods: Based on the principle of flocculation concentration, the method of recovering bacteriophage from water sample was established by using iron ion flocculation combined with membrane filter. The titer of phage was determined by Agar double layer method. The recovery efficiency of phage was detected by phage fluorescence staining and real-time fluorescence PCR reaction. Water samples from different sources were collected for simulation experiment to evaluate the enrichment effect. At the same time, the sewage discharged from hospitals was taken as the actual water sample, and the common clinical drug-resistant bacteria were used as the host indicator bacteria to further analyze the enrichment effect of FeCl₃-PVDF membrane filter rapid enrichment method on the bacteriophage in natural water samples. Results: The method of enrichment of bacteriophages in natural water by iron ion concentration 50 mg/L and PVDF membrane filter was established. The recovery rate of this method for bacteriophage was 93%-100%. Under the multi-functional microscope, it was found that the bacteriophage of the enriched water sample increased significantly and the fluorescence value of the enriched water sample determined by the enzyme labeling instrument was about 13 times as high as that before enrichment. After concentration of the actual water samples from the hospital drainage, the positive rate of bacteriophage isolation in the concentrated group and the non-concentrated group was 23% and 4%, and the fluorescence value in the concentrated group was 2-24 times as high as that of the non-concentrated group. Conclusion: The method of FeCl₃-PVDF membrane filter is a simple, efficient and rapid method for enriching bacteriophages in different water samples.

[Drug resistance and genomic characteristics of a strain of O139 Vibrio cholerae isolated from human bloodstream infection]

Objective: To analyze the drug resistance and genomic characteristics of a strain of serogroup O139 Vibrio cholerae producing cholera toxin isolated from the bloodstream of a person with bacteremia. Methods: The broth dilution method and automatic drug sensitivity analyzer were used to determine the antibiotic sensitivity of the strain. The complete genome sequence of the strain was obtained by using second-generation gene sequencing and nanopore sequencing. BLAST software was used for comparison and analysis with CARD, Resfinder, ISfinder, VFDB, and other databases. The drug-resistant genes, insertion sequences and virulence genes carried by the strain were identified. MEGA 5.1 software was used to construct a genetic phylogenetic tree based on the core genomic single nucleotide polymorphisms. Results: V. cholerae SH400, as the toxigenic strain, carried multiple virulence-related genes and four virulence islands. The strain was resistant to streptomycin, tetracycline and cotrimoxazole, carrying corresponding drug-resistant genes. The strain also carried IncA/C plasmid with the size of 172914 bp and contained 10 drug-resistant genes. Combined with the genomic evolutionary relationship, this study found that the drug-resistant genes and drug-resistant plasmids carried among strains showed certain aggregation. The traditional ST type of strain SH400 was ST69, and the cgMLST type was a new type highly similar to cgST-252. Conclusion: This strain of serogroup O139 V. cholerae carries the ctxAB gene, multiple drug-resistant genes and IncA/C plasmid, and there are multiple drug-resistant islands.

[Clinical features and survival analysis of microscopic polyangiitis-associated interstitial lung disease:a retrospective study of 28 patients]

Objective: To explore the clinical features, laboratory examination and imaging features of microscopic polyangiitis (MPA)-associated interstitial lung disease (ILD), and to perform survival analysis. Methods: The records of 28 patients with MPA-ILD who were treated at the Affiliated Hospital of Medical School of Ningbo University were reviewed retrospectively from August 2014 to November 2021. The patients' clinical features, laboratory parameters, pulmonary function test, echocardiography, chest CT scan findings and therapeutic regimen were analyzed, and the relevant data were statistically analyzed. Results: There were 18 males and 10 females, with an average age of (70.1±9.3) years. Among them, 13 patients had a history of smoking. The main clinical manifestations were cough (14/28), fever (12/28), chest tightness, shortness of breath (12/28) and hemoptysis (3/28). Sixteen patients had renal involvement, and 78.57% (22/28) and 89.28% (25/28) of the patients had elevated C-reactive protein (CRP) and ESR respectively. Sixteen (16/28) patients had increased rheumatoid factor (RF), and the positive rate of myeloperoxidase antineutrophil cytoplasmic antibodies (MPO-ANCA) was 82.12% (23/28). 96.43% (27/28) of ILDs were diagnosed before or at the same time as MPA. The chest radiological pattern was mainly usual interstitial pneumonia (UIP) or UIP-like (15/28), followed by nonspecific interstitial pneumonia (NSIP) (8/28). Compared with non-UIP-like patients, UIP or UIP-like patients were older (P=0.018), and had higher serum LDH level (P=0.041), but serum creatinine level was significantly lower (P=0.041). Univariate and multivariate survival analysis showed that inappropriate treatment (HR=9.81, 95%CI: 1.68-57.29, P=0.011) and elevated serum LDH (HR=4.11, 95%CI: 0.99-17.00, P=0.051) were independent risk factors for shortened survival of MPA-ILD, while elevated RF (HR=0.22, 95%CI: 0.06-0.91, P=0.037) was a protective factor for prolonged survival. Conclusions: MPA-ILD patients had fewer systemic vasculitis symptoms. Most of the ILD patients were diagnosed before or at the same time as MPA. The chest radiological pattern was mainly UIP or UIP-like, followed by NSIP. Early use of glucocorticoids combined with immunosuppressant or rituximab could improve the survival rate of MPA-ILD. The elevated serum LDH was an independent risk factor for shortened survival of MPA-ILD, while elevated RF was a protective factor for prolonged survival.

[Combined application of field epidemiology and laboratory etiology analysis in the investigation of a foodborne disease outbreak in Xinjiang uygur Autonomous Region, 2016]

Objectives: To analyze the causes of a foodborne outbreak in rural areas of Xinjiang between April 2 and April 5 in 2016. Methods: Cases and the relevant background information were obtained by consulting outpatient records of local health centers and regional people's hospitals and interviewing doctors and residents. All samples were collected by the laboratory test through epidemiological and food hygiene investigations. The χ² test (Fisher's exact probability method) was used to compare differences in incidence rates. Molecular typing, virulence genes and single nucleotide polymorphisms (SNPS) were analyzed by using Pulsed Field Gel Electrophoresis (PFGE) and Whole Genome Sequencing (WGS). Results: A total of 142 cases were found in this study, with incidence rate at 5.7‰ (142/24 979). Among all cases, the main symptoms were nausea (94%), vomiting (92%) and abdominal pain (67%), and the incubation period was about 2 h (1-7.5 h). There were 16 Staphylococcus aureus isolates identified and all of them could produce A+C+E mixed enterotoxin. PFGE showed 100% homology. WGS further revealed that there were 9 and 1 strains contained by Sequence Type 1 (ST1) and ST5405, respectively. All ST1 strains were in the same clade on the genome tree. Among these, 7 strains shared close proximity (74 SNPs) and 2 strains shared close relationships as well (127 SNPs). The S. aureus isolates that caused the outbreak were introduced by a mutant isolate from the milk supply station. Conclusions: This foodborne outbreak was mainly caused by Staphylococcus aureus contamination.

[Application and reflection of laboratory-based monitoring in early warning of infectious diseases]

Despite the fact that our cognition towards infectious disease prevention, the advanced technology and the economic status of the whole society has made a great progress in the last decade, the outbreak of COVID-19 pneumonia has again enabled the public to acquire more about super-challenges of infectious diseases, epidemics and the relevant preventive measurements. In order to identify the epidemic signals in early stage or even before the onset of epidemic, the data research and utilization of a series of factors related to the occurrence and transmission of infectious diseases have played a significant role in research of prevention and control during the whole period of surveillance and early warning. Laboratory-based monitoring for the etiology has always been an important part of infectious disease warning system due to pathogens as the direct cause of such diseases. China has initially established a laboratory-based monitoring and early warning system for bacterial infectious diseases based on the Chinese Pathogen Identification Network with an aim to identify pathogens, outbreaks and sources. This network has played an essential role in early detection, tracking and precise prevention and control of bacterial infectious diseases, such as plague, cholera, and epidemic cerebrospinal meningitis. This issue focuses on the function of laboratory-based monitoring during the period of early warning, prevention, and control of bacterial infectious diseases, and conducted a wide range of researches based on the analysis of the epidemic and outbreak isolates, together with field epidemiological studies and normal monitoring systems. All of these could illustrate the effect of laboratory surveillance in the infectious disease risk assessment and epidemic investigation. At the same time, we have put forward our review and expectation of scenarios about laboratory-based monitoring and early warning technologies to provide innovative thoughts for promoting a leapfrog development of infectious disease monitoring and early warning system in China.

[Advance on research and application of laboratory pathogen monitoring and early warning technology of bacterial infectious diseases]

Human beings are still facing the public health challenges from bacterial infectious diseases. Carrying out systematic infectious disease monitoring and early warning is the most direct solution to prevent and control infectious diseases. Etiology is an important part of infectious disease monitoring and early warning. Effective pathogen monitoring can identify pathogens, outbreaks and sources at the first time. In this study, we have reviewed the research and application of etiology monitoring and early warning technology of bacterial infectious diseases and summarized the importance and application scenarios of etiology in infectious disease monitoring and early warning, as well as the research progress of etiology monitoring and early warning technology. Based on the work of existing laboratory monitoring networks, such as Chinese Pathogen Identification Network, the development trend and prospect of infectious disease laboratory network monitoring are put forward to provide a reference for establishing and perfecting the infectious disease monitoring and early warning system.

[Efficacy and safety of ticagrelor versus clopidogrel in Chinese patients with acute coronary syndrome treated with glycoprotein Ⅱb/Ⅲa receptor antagonist]

Objective: To explore the efficacy and safety of ticagrelor versus clopidogrel in acute coronary syndrome (ACS) Chinese patients using glycoprotein Ⅱb/Ⅲa inhibitor (GPI). Methods: The data from CCC-ACS (Improving Care for Cardiovascular Disease in China-ACS) project were systematically reviewed in ACS patients with GPI. The patients were divided into ticagrelor and clopidogrel groups. A logistic analysis and propensity score matching (PSM) were performed to compare occurrences of major cardiovascular events (MACE) and bleeding events between the two groups during hospitalization. Results: A total of 63 641 ACS patients were collected from 150 hospitals. Logistic regression analyses showed that there was no statistically significant difference in the reduction of MACE between ticagrelor and clopidogrel when using GPI (OR=0.881, 95%CI 0.599-1.296; P=0.521). However, major bleeding rate was higher in the ticagrelor group than that in the clopidogrel group (OR=1.401, 95%CI 1.075-1.852; P=0.013). Similar results were observed after PSM. No statistic difference in MACE between the ticagrelor and clopidogrel group (OR=0.919, 95%CI 0.613-1.376; P=0.681). Major bleeding rate was higher in the ticagrelor group (OR=1.559, 95%CI 1.130-2.150; P=0.007). Conclusion: In ACS patients with GPI, ticagrelor did not reduce MACE, but increased the major bleeding risk compared with clopidogrel.

[Results and cost-effectiveness of colorectal cancer screening program among urban residents in Zhejiang province, 2013-2018]

Objective: To analyze the results and cost-effectiveness of colorectal cancer (CRC) screening program among Zhejiang urban residents so as to provide evidence for further optimization of CRC screening strategies. Methods: Based on the Cancer Screening Program in Urban China which was conducted in Zhejiang province from 2013-2018, data related to the rates on compliance and detection through the CRC screening program among the 40-74 year-old residents were analyzed. Chi-square tests were used to compare the differences among groups, and multivariate logistic regression models were applied to explore the potential risk factors. Cost-effectiveness ratio (CER) was calculated by using the cost per lesion detected as the indicator. Results: Among all the 166 285 participants who completed the risk assessment questionnaire, 21 975 (13.2%) were recognized as under the high risk of CRC and 4 389 (20.0%) of them received the colonoscopy. The detection rates of CRC, advanced adenoma, and non-advance adenoma were 0.3% (11 cases), 2.7% (119 cases), and 5.2% (229 cases), respectively. Results from the multivariate logistic regression analyses showed that factors as age, gender, education level, smoking, drinking alcohol, previous fecal occult blood test (FOBT), polyp history, and family history of CRC were significantly associated with the compliance rate of colonoscopy while age, smoking and polyp history were significantly associated with the detection rate of advanced neoplasms (CRC and advanced adenoma). The costs were ￥22 355.74 Yuan for every CER advanced neoplasm detection and ￥264 204.18 Yuan per CRC detection, respectively. The CER decreased along with ageing. Sensitivity analysis showed that CERs were expected to decrease when the compliance rate of colonoscopy was increasing. Conclusions: The current screening program seems effective in detecting the precancerous colorectal lesions, but the relatively low compliance rate of colonoscopy restricting both the diagnostic yields and economic benefits. It is necessary to improve the awareness and acceptance of colonoscopy among the high-risk CRC population.

Effects of cold stress on growth performance, serum biochemistry, intestinal barrier molecules, and adenosine monophosphate-activated protein kinase in broilers

The homeostasis dysfunctions caused by cold stress remain a threat to intestinal health, particularly for young broiler chickens. We hypothesized that adenosine monophosphate-activated protein kinase (AMPK) was involved in the regulation of cold stress on intestinal health. This study aimed to examine the effect of cold stress for 72 h on growth performance, serum biochemistry, intestinal barrier molecules, and AMPK in broilers. A total of 144 10-day-old male Arbor Acres broilers were subjected to temperature treatments (control 28  ± 1 °C vs cold stress 16 ± 1 °C) for 72 h. Growth performance was monitored, serum was collected for the analysis of physiological parameters, and jejunal mucosa was sampled for the determination of tight junction (TJ) proteins, heat shock proteins, and AMPK signaling molecules. Results showed that 72 h cold treatment reduced average BW gain and increased the feed conversion ratio of the broilers (P < 0.05). Cold stress for 72 h increased blood endotoxin, aspartate aminotransferase, glucose, and low-density lipoprotein cholesterol levels (P < 0.05). Moreover, 72 h cold treatment up-regulated jejunal Occludin, zonula occludin 1, inducible nitric oxide synthase, heat shock factor 1, and AMPKα1 gene expression (P < 0.05) but had no obvious effect on total AMPK protein expression (P > 0.05). In conclusion, cold stress significantly reduced the growth performance of broiler chickens. The intestinal barrier function might be impaired, and enhanced bacterial translocation might occur. The unregulated gene expression of TJ proteins implied the remodeling of intestinal barrier. The change of AMPK suggested the possible relationship between intestinal energy metabolism and barrier function under cold stress.

Comparison between tunneling and standard endoscopic submucosal dissection for treatment of large esophageal superficial neoplasm

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) has been established as a standard endoscopic method for treating esophageal superficial neoplasms, and it can be performed using a conventional or a tunneling method. The aim of the present study was to compare the safety and efficacy of tunneling ESD (t-ESD) and standard ESD (s-ESD) for treating large esophageal superficial neoplasms and to explore the risk factors for postoperative strictures.

PATIENTS AND METHODS

Fifty-five consecutive patients with large esophageal superficial neoplasms were treated by t-ESD or s-ESD. Demographics, lesion characteristics, procedure-related parameters, and follow-up results were retrospectively collected to compare the efficacy and safety of these procedures. Multivariate analyses were conducted to determine the potential risk factors for postoperative strictures.

RESULTS

Of the 55 patients, 13 underwent t-ESD and 42 underwent s-ESD. The dissection speed of t-ESD was significantly faster than that of s-ESD (7.42±1.99 min/cm2 vs. 9.01±2.11 min/cm2, P<0.05). En bloc resection was achieved in 98.2% (54/55) of the cases, while R0 resection was achieved in 92.7% (51/55). Curative resection was achieved in 78.2% (43/55) of the cases. Fourteen patients (25.5%) had postoperative strictures, which resolved with endoscopic dilation and/or stent insertion. Circumferential involvement of >3/4 and lesion length of >3 cm were independent risk factors for strictures.

CONCLUSIONS

T-ESD is a safe and effective method for treating large esophageal superficial neoplasms with a faster dissection speed than s-ESD, but postoperative strictures may be encountered for lesions involving more than three-fourths of the circumference or longer than 3 cm.

[Molecular epidemiology of carbapenem resistant Klebsiella pneumoniae in a hospital in Beijing]

Objective: To reveal the molecular epidemiological characteristics of Carbapenem-Resistant Klebsiella pneumoniae (CRKP) isolated from a three level teaching hospital in Beijing. Methods: Pulsed field gel electrophoresis (PFGE) was carried out to subtyping 375 CRKP isolated in that hospital between May 2010 and October 2015. Fifteen strains were chose based on the PFGE patterns to be analyzed by multi-locus sequence typing (MLST) and detection of carbapenem-resistance genes. One strain (A1502) was selected for whole genome sequencing and analyzing. Results: The 375 CRKP were divided into 140 PFGE types, among which five types contained more than five strains. The dominant types were distributed in different time periods and wards. Among the 15 strains tested by MLST and carbapenem-resistance genes detection, 13 were ST11 strains carrying KPC-2 gene. By genome-based typing, A1502 was clustered together with strains from other hospitals of Beijing but far from the strains from Shanghai and Hangzhou. Conclusion: The CRKP epidemic clone (ST11 clone carrying KPC-2) has been spreading within single hospital and across different hospitals in Beijing.

Industrial scale garage-type dry fermentation of municipal solid waste to biogas

The objectives of this study was to through monitoring the 1st industrial scale garage-type dry fermentation (GTDF) MSW biogas plant in Bin County, Harbin City, Heilongjiang Province, China, to investigate its anaerobic digestion (AD) performance and the stability of process. After a monitoring period of 180days, the results showed that the volumetric biogas production of the digesters and percolate tank was 0.72 and 2.22m(3) (m(3)d)(-1), respectively, and the specific biogas yield of the feedstock was about 270m(3)CH4tVS(-1), which indicated that the GTDF is appropriate for the Chinese MSW. This paper also raised some problems aimed at improving the process stability and AD efficiency.

[Clinical characteristics analysis of 120 cases of pediatric spinal cord injury without radiologic abnormality]

OBJECTIVE

To study the epidemiologic characteristics of pediatric spinal cord injury without radiologic abnormality.

METHODS

A retrospective analysis was performed and 120 cases of children with spinal cord injury without radiologic abnormality were admitted in China Rehabilitation Research Center from January 2005 to December 2014.The gender, age, causes of injury, injury condition and complication were analyzed. All cases were divided into two groups (0-7 years old and 8-13 years old) according to age.

RESULTS

One hundred and twenty cases included 31 boys (25.8%) and 89 girls (74.2%). Most of the children were 0-7 years old (96 cases, 80.0%). The top 3 causes of spinal cord injury were sports activities (60 cases, 50.0%), traffic accident (25 cases, 29.2%) and other trauma (11 cases, 12.5%). Seventy-one cases were low-energy injury (59.2%) and 49 cases were high-energy trauma (40.8%), most of low-energy injury were completely injured (56 cases, 78.9%). The complication rate was 59.2% and the top 3 complications were urinary infection (35 cases, 29.2%), hydronephrosis (12 cases, 10.0%) and pressure ulcers (10 cases, 8.3%).

CONCLUSION

It is needed to pay more attention to pediatric spinal cord injury without radiologic abnormality caused by low-energy injury, especially children aged 0-7 years old with history of slight injury, and be careful about spinal cord injury without radiologic abnormality result from high-energy damage.

X-ray radiation promotes the metastatic potential of tongue squamous cell carcinoma cells via modulation of biomechanical and cytoskeletal properties

This study investigated the metastatic potential of tongue squamous cell carcinoma (TSCC) cells after X-ray irradiation as well as radiation-induced changes in the biomechanical properties and cytoskeletal structure that are relevant to metastasis. Tca-8113 TSCC cells were X-ray-irradiated at increasing doses (0, 1, 2, or 4 Gy), and 24 h later, migration was evaluated with the wound healing and transwell migration assays, while invasion was assessed with the Matrigel invasion assay. Confocal and atomic force microscopy were used to examine changes in the structure of the actin cytoskeleton and Young's modulus (cell stiffness), respectively. X-ray radiation induced dose-dependent increases in invasive and migratory potentials of cells relative to unirradiated control cells (p < 0.05). The Young's modulus of irradiated cells was decreased by radiation exposure (p < 0.05), which was accompanied by alterations in the integrity and organization of the cytoskeletal network, as evidenced by a decrease in the signal intensity of actin fibers (p < 0.05). X-ray irradiation enhanced migration and invasiveness in Tca-8113 TSCC cells by altering their biomechanical properties and the organization of the actin cytoskeleton. A biomechanics-based analysis can provide an additional platform for assessing tumor response to radiation and optimization of cancer therapies.

Effects of dietary supplementation of multi-enzyme on growth performance, nutrient digestibility, small intestinal digestive enzyme activities, and large intestinal selected microbiota in weanling pigs

Two experiments were conducted to assess the effects of dietary supplementation of an exogenous multi-enzyme (EME) preparation to 35- to 65-d-old piglets on apparent total tract digestibility (ATTD), growth performance, digestive enzyme activities, and selected microbial populations in feces. In Exp.1, twenty eight 35-d-old piglets were randomly assigned to 7 dietary treatments (corn-soybean based diet supplemented with 0, 100, 150, 200, 250, 300, or 350 mg EME/kg) in a 14-d digestibility study. Piglets fed the diets supplemented with EME had greater ATTD of DM, CP, and GE (P = 0.001, 0.005, and 0.009, respectively) than those fed the diet without EME supplementation, and those ATTD values increased linearly and quadratically (P < 0.001) as the levels of supplemented EME increased. In Exp. 2, two hundred 35-d-old weanling piglets were randomly allocated to 20 pens. The pens were then randomly assigned to 5 dietary treatments (corn-soybean based diet supplemented with 0, 100, 150, 250, or 350 mg EME/kg) with 4 pens per treatment in a 30-d feeding experiment. Piglets has ad libitum access to diets and water, and they were weighed at the beginning (35-d-old), middle (50-d-old), and end (65-d-old) of the experiment. Fecal samples were grabbed directly from the rectum and digesta samples from duodenum, jejunum, and ileum were taken at the end of the experiment for the analysis of selected bacteria populations and digestive-enzyme activities. The ADG and ADFI tended to be greater with the increasing levels of supplemented EME in both periods, whereas G:F was improved (P = 0.012 and 0.017) by EME in the period of 35 to 50 d of age and during the overall experimental period. Furthermore, inclusion of EME in diet increased the counts of Lactobacilli spp. and Bacillus subtilis spp., but reduced the populations of Salmonella spp. and Escherichia coli spp. in the feces. The EME supplementation also enhanced (P < 0.05) the activities of amylase, lipase, and protease in the small intestine. The growth performance-enhancing effects of EME appeared to be mediated by the age of the piglet and the dose of EME used. Supplementation of corn-soybean meal diets for 35- to 65-d-old piglets with EME has a potential to enhance gut health condition, increase nutrient digestion, and increase growth performance.

Caecal transcriptome analysis of colonized and non-colonized chickens within two genetic lines that differ in caecal colonization by Campylobacter jejuni

Campylobacter jejuni is one of the most common causes of human bacterial enteritis worldwide. The molecular mechanisms of the host responses of chickens to C. jejuni colonization are not well understood. We have previously found differences in C. jejuni colonization at 7-days post-inoculation (pi) between two genetic broiler lines. However, within each line, not all birds were colonized by C. jejuni (27.5% colonized in line A, and 70% in line B). Therefore, the objective of the present experiments was to further define the differences in host gene expression between colonized and non-colonized chickens within each genetic line. RNA isolated from ceca of colonized and non-colonized birds within each line was applied to a chicken 44K Agilent microarray for the pair comparison. There were differences in the mechanisms of host resistant to C. jejuni colonization between line A and line B. Ten times more differentially expressed genes were observed between colonized and non-colonized chickens within line B than those within line A. Our study supports the fact that the MAPK pathway is important in host response to C. jejuni colonization in line B, but not in line A. The data indicate that inhibition of small GTPase-mediated signal transduction could enhance the resistance of chickens to C. jejuni colonization and that the tumour necrosis factor receptor superfamily genes play important roles in determining C. jejuni non-colonization in broilers.

Relationship between serum hepatitis B virus DNA and surface antigen with covalently closed circular DNA in HBeAg-negative patients

Hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) is responsible for viral persistence. This study aimed to investigate the serum surrogate markers for cccDNA and to evaluate the intrahepatic viral events associated with disease activity in HBeAg-negative chronic hepatitis B patients. Thirty-three treatment-naïve patients with a negative HBeAg who had a liver biopsy were studied. Active disease was defined as a serum alanine aminotransferase >40 IU/L and a serum HBV DNA >10,000 copies/ml. This study showed significant correlation between serum HBV DNA and both log cccDNA (r = 0.41, P = 0.018) and log total intrahepatic HBV DNA (r = 0.71, P < 0.0001). No significant correlation was observed between serum HBsAg and log cccDNA (P = 0.15) or log total intrahepatic HBV DNA (P = 0.97). Fourteen and 19 patients had inactive and active disease, respectively. The median log cccDNA and log total intrahepatic HBV DNA (copies/10(6) cells) were significantly higher in patients with active disease compared with those with inactive disease (4.11 vs. 3.53, P = 0.03 and 5.46 vs. 4.64, P < 0.001, respectively). The HBV replicative efficiency, defined as the ratio of serum HBV DNA to cccDNA, was approximately 20% higher in patients with active disease. No significant difference was observed in the HBsAg levels and the ratio of serum HBsAg to cccDNA between the two groups. In conclusion, serum HBV DNA, but not HBsAg, reflects the amount of cccDNA and the replication efficiency of HBV in patients with HBeAg-negative chronic hepatitis B.

Chirped-quasi-periodic structure for quasi-phase-matching

We propose in this paper a chirped-quasi-periodic structure using the projection method. This type of new structure combines the advantages of chirped and quasi-periodic structures, and can be used for both multiple quasi-phase-matching and multiple bandwidths control. Numerical simulation of second-harmonic generation performance is in good agreement with the Fourier spectrum of the structure.

Significant histopathology in Chinese chronic hepatitis B patients with persistently high-normal alanine aminotransferase

Current guidelines recommend antiviral therapy for chronic hepatitis B (CHB) patients with elevated alanine aminotransferase (ALT) and high viral load. Scant histological data exist for CHB patients with persistently normal ALT (PNALT) because disease progression is thought to be rare. To identify potential predictors of significant histology in the presence of PNALT, we compared the clinical characteristics and histology of Chinese CHB PNALT patients to those in patients with elevated ALT. Percutaneous liver biopsy was performed in 522 CHB patients with Chinese ethnicity who had not had antiviral treatment. Differences in age, ALT, viral load, hepatitis B e antigen (HBeAg) status and liver histology were compared between eligible PNALT (252) and elevated ALT (270) patients. Of the PNALT patients, 38.5% had normal liver histology, 25.4% had significant necroinflammation and/or fibrosis and 8.4% had established cirrhosis. Furthermore, histopathological differences between patients with high-normal ALT (0.5-1.0 x the upper limit of normal (ULN)) and low-normal ALT (≤ 0.5 x ULN) were evaluated. There was a significantly greater prevalence of histopathology in the high-normal group (40.0%) than in the low-normal group (16.6%) (P < 0.001). Multiple logistic regression identified that significant histopathology findings in PNALT patients correlated with age (P < 0.001) and ALT level (P < 0.001), with age >40 years and ALT >0.5 x ULN predicting significant histopathology. Our data indicate that liver biopsy is recommended in CHB patients >40 years of age, particularly when their ALT is 0.5-1.0 x ULN. The findings above provide evidence for indication of antiviral therapy in patients with PNALT and significant histopathological change.

Supratentorial Brain AVM Embolization with Onyx-18 and Post-Embolization Management. A Single-Center Experience

SUMMARY

Onyx is increasingly used in endovascular therapy of intracranial arteriovenous malformations (AVMs). However, the embolic effect and post-embolization management are still under discussion. We report our experience in the treatment of supratentorial brain arteriovenous malformations (SBAVMs) with Onyx and discuss post-embolic management. From June 2006 to July 2008, 20 patients with SBAVM were embolized with Onyx. There were 14 men and six women ranging from 14 to 64 years of age (mean 38.3 years). Initial symptoms included spontaneous hemorrhage (n=12), headaches (n=4), seizure (n=3) and incidentally disclosed after head trauma (n=1). After the endovascular procedure, all had subsequent treatment (follow-up angiogram, stereotactic radiosurgery or microsurgery) according to the obliteration degree. At angiography, seven patients (35%, 7/20) were completely obliterated (over 95% closure) after embolization while one suffered a small subarachnoid hemorrhage without permanent clinical sequelae. Four patients (20%, 4/20) were subtotally obliterated (over 80% closure), one patient who suffered severe cerebral edema after embolization underwent decompressive craniectomy, two patients had additional radiosurgery and one patient had follow-up angiogram. Nine patients (45%, 9/20) were partially obliterated (20-80% closure), five patients had additional surgery, two patients had additional radiosurgery and two patients had follow-up angiogram (one patient had intraventricular hemorrhage three months after embolization). Of all 20 AVMs, an average of 2.2 ml Onyx was used per patient and average volume reduction was 80% (range, 30%-99%). Onyx is suitable for embolization of SBAVMs because of its diffuse controllable properties. We suggest clinical follow-up after complete obliteration, additional radiosurgery or angiographic follow-up after subtotal obliteration and additional surgery after partially obliteration. More cases with long-term follow-up are needed to evaluate the long-term prognosis of our post-embolization management.

Magnetic properties in Co and Mn-doped ZnO powders and thin films

Zn0.86Co0.14O powder and thin films were prepared by standard solid-state reaction processes and radio-frequency (RF) magnetron sputtering. Magnetic measurements indicate that the powder is paramagnetic for temperatures above 3 K, while the thin films annealed in vacuum are ferromagnetic at room temperature. The saturated magnetization was found to be about 0.6 microB/Co, while the coercive force was found to be 200 Oe at room temperature. The very similar results were also obtained in Zn0.96Mn0.04O powder and thin films. Such different results for the powder and thin films indicate that growth conditions and defects play an important role in producing ferromagnetism.

Primary small-bowel non-Hodgkin's lymphoma: a study of clinical features, pathology, management and prognosis

The records of 34 patients diagnosed with primary small bowel non-Hodgkin's lymphoma during a 10-year period between January 1996 and December 2005, including 27 cases for which complete follow-up records were available, were studied. Abdominal pain (70.6% of patients) was the main presenting symptom, followed by intestinal obstruction (38.2%). The most common primary site was the ileum (58.8%), followed by the jejunum (26.5%) and duodenum (17.6%); one case had tumours at two sites in the small bowel. Twenty-seven patients had small bowel B-cell lymphoma (24 diffuse large B-cell lymphoma; three mucosa-associated lymphoid tissue B-cell lymphoma) and seven patients had small bowel T-cell lymphoma. Cumulative survival in patients with small bowel B-cell lymphoma was higher than that in patients with small bowel T-cell lymphoma. Data on 16 male and eight female patients with diffuse large B-cell lymphoma showed that 62.5% of these patients presented with disease stages I or II and 37.5% with stages III or IV. Cumulative survival in patients at stages IE or IIE was significantly higher than that of patients at stages IIIE or IVE. Four of five patients who died from diffuse large B-cell lymphoma had abnormal levels of lactate dehydrogenase and serum albumin.

Loss of expression of Kruppel-like factor 6 in primary hepatocellular carcinoma and hepatoma cell lines

KLF6 (Zf9, COPEB), an ubiquitous transcription factor, maps to chromosome 10p. Recently, KLF6 was found to have a more generalized role in tumorigenesis as a candidate tumor suppressor gene for some tumors. However, results from other published studies seem not to be in agreement with data from previous studies. Gene-expression analysis is increasingly important in biological research. Loss of expression is one of the mechanisms to functionally inactivate a tumor suppressor gene. To investigate the expression change of KLF6 gene associated with HCC as a step toward a better understanding of the molecular pathophysiology, and to provide the basis for analysis of KLF6 gene in HCC carcinogenesis. We analyzed the expression of KLF6 mRNA in 26 samples of HCC tissues and hepatoma cell lines(Hep3B and HepG2) detected by Real-Time quantitative RT-PCR (qRT-PCR) and conventional RT-PCR assay. To confirm and extend the data obtained at RNA level, we performed detailed immunoblotting analysis on HCC tissues and hepatoma cell lines using a rabbit polyclonal antibody specific for KLF6. NKLF6 detected by qRT-PCR from HCC and corresponding noncancerous tissues was 0.04+/-0.038 and 0.116+/-0.101, respectively. These data demonstrated that KLF6 mRNA level was significantly decreased in HCC, compared with corresponding noncancerous tissues (t =3.683 , P<0.001). The frequency of Hepatoma Cell Lines with KLF6 down-regulation detected by conventional PT-PCR, seems to be consistent with a previous study using real-time PCR assays in tumor samples. KLF6 expression levels were determined by Western blot. Compared to the matched surrounding tissues, a clear decrease of KLF6 protein levels in tumor tissues was observable (t=13.59, P<0.001). Hepatoma cell lines also showed low-level of KLF6 protein (P<0.01) expression. Immunohistochemistry and immunocytochemistry showed a faint diffused staining in the HCC tissues and hepatoma cell lines, and endogenous KLF6 protein was detected mostly in the cytoplasm. KLF6 gene appeared markedly reduced in HCC tissues and hepatoma cell lines. Frequent down-regulation of KLF6 strongly suggested that it is a candidate of tumor suppressor gene for HCC.

Observation of locomotor functional recovery in adult complete spinal rats with BWSTT using semiquantitative and qualitative methods

STUDY DESIGN

Experimental rat model of spinal cord transection .

SETTING

China rehabilitation research center.

OBJECTIVE

To investigate locomotor functional recovery in spinal rats with BWSTT using semiquantitative and qualitative methods.

METHODS

Five-day postoperative (dpo), adult female complete spinal rats (at T(8) level) received 40 days of body weight-supported treadmill training (BWSTT). Signs of functional recovery were examined with average combined scores (ACOS) and Basso Beattie and Bresnahan (BBB) scales at different time points.

RESULTS

At 1-dpo, none of the spinal rats exhibited hindlimb movements. The spinal rats displayed functional progress with time, but the rare could recover to full weight-bearing hindlimb at 45-dpo. BBB and ACOS scores in the BWSTT group obtained better scores than those in the spinal cord injury (SCI) group at 30- and 45-dpo. Furthermore, all BBB and ACOS scores of spinal rats reached statistical significance between 7- and 30-dpo, and between 15- and 30-dpo. However, only ACOS but not BBB scores in the SCI and BWSTT groups showed statistics differences between 15- and 45-dpo, and between 30- and 45-dpo. The Spearman correlation coefficients of BBB and ACOS scores were 0.913 and 0.972 for the SCI and BWSTT groups, respectively.

CONCLUSIONS

The results confirmed the existence of partial spontaneous hindlimb functional recovery in adult chronically spinal cord-transected rats, and that BWSTT can improve motor performance. In addition, our study suggests that qualitative and semiquantiative methods are strongly correlated with locomotor recovery in spinal rats, and the latter may be more sensitive in reflecting minor variance at different time points.

Refined Techniques for Intestinal Transplantation in Rat

Intestinal transplantation (IT), unlike other solid-organ transplantations, such as liver, kidney, and heart, has relatively disappointing results in humans. Significant advances have been made during the past 40 years, but rejection, graft-versus-host disease (GVHD), and infection remain the major obstacles to successful IT. These aspects may be studied using a rat model of IT. Without a microscope and traditional suture for vascular reconstruction, we simplified the procedure using a "three cuffs" technique for orthotopic intestinal transplantation (OIT). Technical modifications of our OIT model that induced good results included (1) adopting a "double cuffs" technique on the graft aorta, (2) using a portal cuff anastomosis to reconstitute the natural and physiologic portal graft drainage with the cuff fixed to the recipient first, and (3) administering a large volume of crystalloid or whole blood to maintain blood pressure and reduce ischemic injury to the graft during operation. In our group, the survival rate of recipients was 87.5% (21 of 24 rats), the average volume of bleeding in the recipient operation was less than 1 mL, and the cold ischemic time, 50 +/- 11 minutes.

Association of renal function and delta-aminolevulinic acid dehydratase polymorphism among Vietnamese and Singapore workers exposed to inorganic lead

OBJECTIVES

To investigate the effect of delta-aminolevulinic acid dehydratase (ALAD) polymorphisms on the association between blood lead and renal function among Vietnamese and Singaporean workers who were exposed to low to medium levels of inorganic lead, and to study the distribution of ALAD polymorphism among Vietnamese, Chinese, Malays and Indians.

METHODS

A total of 459 male and female workers were studied. Blood and urine were collected for each worker in order to determine ALAD genotype, blood lead, and urinary delta-aminolevulinic acid (ALAU). Renal function tests included urine albumin (Ualb), urine beta2 microglobulin (Ubeta2m), urinary alpha1 microglobulin (Ualpha1m), N-acetyl-glucosaminidas (NAG), and urine retinol blinding protein (RBP). A multiple regression model with interaction term was applied to fit the entire data and to explore the modifying effect of ALAD polymorphism on the relation of blood lead to each renal function parameter.

RESULTS

ALAD1-1 was the predominant genotype for all the ethnic groups while ALAD2-2 was the rarest. The frequency of ALAD2 allele was higher among Malays (8.8%) and Indians (10.6%) compared to the Chinese (5.0%) and Vietnamese (4.3%). The geometric mean of blood lead for all workers was 19.0 microg/dl. The models for Ubeta2m, Ualpha1m, and NAG showed that the ALAD1-2/2-2 group had higher beta coefficients than the ALAD1-1 group. Corresponding to 10 microg/dl blood lead, ALAD1-1 homozygotes had an increment of 1.288 microg/g Cr, 1.175 mg/g Cr, and 1.995 U/g Cr for Ubeta2m, Ualpha1m, and NAG, respectively. ALAD1-2/2-2 subjects had higher increments of 3.802 microg/g Cr, 2.138 mg/g Cr, and 3.89 U/g Cr for Ubeta2m, Ualpha1m, and NAG, respectively.

CONCLUSION

The frequency of the ALAD2 allele is as low in Vietnamese workers as in Chinese. Workers with the ALAD2 allele appeared more susceptible to the effects of lead (especially at higher levels) on renal function.

Rabi oscillation damped by exciton leakage and Auger capture in quantum dots

The decoherence of Rabi oscillation (RO) caused by biexciton, population leakage to the wetting layer (WL), and Auger capture in semiconductor quantum dots is theoretically analyzed with multilevel optical Bloch equations. The corresponding effects on the quality factor of RO are also discussed. We have found that the biexciton effect is relatively trifling, as the pulse duration is longer than 5 ps. The population leakage to the WL leads to a decrease of the RO average even though the damping rate is similar to that observed in the experiment. Auger capture in quantum dots results in RO damping that is consistent with the experimental data, which implies that Auger capture is an important decoherence process in quantum dots.

Coherent control of a V-type three-level system in a single quantum dot

In a semiconductor quantum dot, the IIx and IIy transitions to the polarization eigenstates, |x> and |y>, naturally form a three-level V-type system. Using low-temperature polarized photoluminescence spectroscopy, we have investigated the exciton dynamics arising under strong laser excitation. We also explicitly solved the density matrix equations for comparison with the experimental data. The polarization of the exciting field controls the coupling between the otherwise orthogonal states. In particular, when the system is initialized into \Y>, a polarization-tailored pulse can swap the population into |x>, and vice versa, effectively operating on the exciton spin.

The changes of gene expression profiles in hydatidiform mole and choriocarcinoma with hyperplasia of trophoblasts

The purpose of this study is to investigate changes of gene expression profiles in hydatidiform moles (HM) and choriocarcinoma and to explore causes of trophoblastic hyperplasia. Using cDNA microarray, 4,096 genes were analyzed in two pairs of the tissues of HM versus normal villi and in two pairs of normal primary culture trophoblasts versus JAR cell line of choriocarcinoma. The expressions of two genes in normal villi and HM, as well as in JAR and JEG-3, were examined with the help of immunohistochemistry, immunoblot, and reverse transcriptase-polymerase chain reaction in order to confirm the findings of cDNA microarray. Twenty-four genes were upregulated and 65 genes were downregulated in all HM. Four hundred thirty-three genes were upregulated and 380 genes were downregulated in JAR. Forty-six genes were upregulated in both HM and choriocarcinoma, whereas 13 genes were downregulated. Genes associated with the inhibition of cell proliferation were significantly downregulated, whereas genes associated with cell proliferation, malignant transformation, metastasis, and drug resistance were upregulated. Thymidine kinase-1 (TK-1) and small subunit ribonucleotide reductase (RRM-2) were overexpressed in HM, JAR, and JEG-3. The expressions of TK-1 and RRM-2 in moles were positively correlated with proliferative index of trophoblasts. Our results suggest that altered expression of genes exist in HM and choriocarcinoma. Trophoblastic hyperplasia may be involved in the overexpression of DNA synthetic enzymes.

Inhibition of LZIP-mediated transcription through direct interaction with a novel host cell factor-like protein

Host cell factor 1 (HCF-1) is a cellular transcriptional coactivator which coordinates the assembly of enhancer complex through direct interactions with viral and cellular trans-activators such as VP16, Oct-1, LZIP, and GA-binding protein. These interactions are mediated by the beta-propeller domain comprising the first 380 residues of HCF-1 with six kelch repeats. Here we describe the identification and characterization of a novel HCF-like kelch repeat protein, designated HCLP-1. HCLP-1 is a ubiquitously expressed nuclear protein which is composed almost entirely of a six-bladed beta-propeller. HCLP-1 selectively interacts with LZIP but not with VP16. The physical interaction between HCLP-1 and LZIP leads to the repression of the LZIP-dependent transcription. The HCLP-1-binding domain of LZIP maps to residues 109-315, which contain the bZIP DNA-binding motif. Electrophoretic mobility shift assay demonstrates that HCLP-1 indeed interferes with the binding of LZIP to its DNA target. Thus, HCLP-1 serves a transcriptional co-repressor function mediated through its inhibitory interaction with the LZIP transcription factor. Our findings suggest a new mechanism for transcriptional regulation by HCF-like proteins.

[Effects of artesunate on progestrone estrogen content and decidua in rats]

AIM

To observe the effect of artesunate on content of progesterone, estrogen and decidua of pregnant rats and study the efficacy and mechanism of artesunate for termination of early pregnancy.

METHODS

Serum content of progesterone, estrogen and TNF-alpha were measured with RIA. The effects of artesunate on the ovary, decidua and fetus of pregnant rats were studied using histochemistry techniques. Decidual cells were estimated using cell culture.

RESULTS

Artesunate 40 mg.kg-1 s.c. on day 6-10 of gestation significantly decreased the concentration of serum progesterone in early pregnant rats; decidual cells and fetus of treated groups were found to be degenerated at d 11. Artesunate was shown to directly damage the decidual cells. Cultured human decidual cells were exposed to artesunate for 48 h, the LC50 was found to be 25 +/- 3 mL.L-1.

CONCLUSION

The damage of artesunate on decidua and placenta may be the mechanisms of its contragestational action.

Termination of early pregnancy in the mouse, rat and hamster with DL111-IT and RU486

The effectiveness of DL111-IT and RU486 given alone and in combination for terminating early pregnancy was tested in the rat, mouse, and hamster. In the mouse and rat, the combination of RU486 and DL111-IT is much more effective in terminating pregnancy than either of the two compounds used alone (single or multiple treatment). A low-effective dose of DL111-IT in combination with a non-effective or a sub-effective dose of RU486, exerted additive or synergistic effects resulting in resorption of embryos and termination of pregnancy. The serum progesterone concentrations were significantly suppressed by these combinations when pregnancy was terminated. In the hamster, single treatment with DL111-IT plus RU486 exhibited a strong effect on interrupting early pregnancy. The ED50 of RU486 in combination of a non-effective dose of DL111-IT was decreased to 163-fold lower dose than RU486 given alone. It is concluded that in mouse, rat, and hamster, the synergistic action between DL111-IT and RU486 not only greatly enhances efficacy in terminating pregnancy but also reduces substantially the dose required to produce this effect.

Intrathecal injection of corticotropin inhibited nitric-oxide synthase-positive neuron increase in rat spinal cord after formalin-induced hyperalgesia

AIM

To study the effects of corticotropin (Cor) on formalin-induced hyperalgesia and the change of nitric-oxide synthase (NOS)-positive neurons in spinal dorsal horn in rats.

METHODS

Measurement of pain intensity rating (PIR), NADPH-d histochemistry, and Fos immunohistochemistry were adopted.

RESULTS

The increases of NOS-positive neurons, Fos, NOS/Fos double labelling neurons of the spinal dorsal horn and the PIR after formalin injection were markedly inhibited by intrathecal injecting (ith) Cor (0.5-1.5 U), which were obviously attenuated by L-arginine (Arg, 5-15 nmol, ith), the substrate of NOS.

CONCLUSION

Cor inhibits formalin-induced hyperalgesia by the decrease of NOS-positive neurons in the spinal dorsal horn of rats.

Analysis of a vertical-cavity surface-emitting laser-based bidirectional free-space optical interconnect

The design of a bidirectional free-space optical interconnect system is presented. Vertical-cavity surface-emitting laser (VCSEL) arrays as a coherent light source and VCSEL beam collimation are described. Hologram array design and a way to improve the diffraction efficiency by use of a copying technique utilizing Dupont photopolymers are presented. Scattering from the hologram as a noise source is measured. An optical model for the design of system parameters such as the VCSEL beam diameter, size and apodization of the hologram, and size of the detector is given on the basis of cross-talk analysis of the system. The effect of VCSEL wavelength variation on system design is considered. Aberrations caused by the Fourier lens in the system are calculated, and ways for correction of the aberrations are discussed.

Characterization of Dupont photopolymers in infrared light for free-space optical interconnects

Dupont photopolymer as a potential holographic material for an optical interconnect system was studied. The optimized conditions of recording plane-wave holograms with ∼99% effective diffraction efficiency for infrared reconstruction were obtained by testing different Dupont photopolymers and different copying parameters. The scattering ratios of the holograms recorded with Dupont photopolymers HRF600-10, HRF600-20, and HRF600-38 were measured and compared.

Embryotoxicity and teratogenicity of DL111-IT, an early pregnancy-terminating agent, in the subsequent gestation following administration in rats

DL 111-IT is a new non-hormonal early pregnancy-terminating agent. The subsequent embryotoxic and teratogenic effects of DL111-IT were studied in the rats whose first pregnancy had been terminated by the agent. The secondary pregnancy of the treated rats were allowed to initiate at 30-, 45-, and 90-day intervals, respectively, after the termination of the first pregnancy. The toxicities primed with DL111-IT, such as resorbed embryos and nephrohydrosis fetuses, were found to be 8.0% and 8.5%, respectively, in the rats with pregnancy at 30-day interval. This is significantly different from 4.0% resorbed embryos and 2.4% nephrohydrosis fetuses in vehicle control (P less than 0.05). However, the rate of resorbed embryos decreased to 7.0% or 6.0% in the rats with pregnancy at 45- or 90-day intervals, respectively. No other significant embryotoxicity and teratogenicity were observed in those rats initiating their pregnancy 45 days later after first-pregnancy termination by DL111-IT. Thus, DL111-IT appears to have very low subsequent toxicity in the course of rat pregnancy cycles.

[Latin square vs twin crossover design for mouse blood glucose assay to estimate insulin potency]

According to parallel line analysis, a Latin square design was used for estimating insulin potency in mouse blood glucose assay. Four to six groups of 4 x 4 Latin squares were used to estimate 80%, 100% and 120% standard preparations and the recovery rates were 95-106%. Meanwhile, in comparison with twin crossover design, 13 batches of variant preparations including some beyond expiry dates were checked by Latin square design. The results showed that the potencies were about the same in two designs. The average fiducial limit rates were still less than 25% but 40% or so of animal numbers were saved. Therefore, Latin square design in a precise and accurate assay for the estimation of insulin.

[Multivariate twin crossover design parallel line assay for estimating potency of insulin]

Based on twin crossover design, a multivariate assay design was used in parallel line analysis to estimate the potency of insulin. This paper describes how to make the experimental design. After the analysis of variance according to assay, the potency and fiducial limits were calculated by the method (2.2). It has been applied by multivariate assay to estimate 80, 100 and 120% standard preparation and the recovery rate were between 94 and 108%. We also tested various batches and agent products. The average fiducial limits rates were less than 20%. In comparison with twin crossover analysis as usual, multivariate assay appeared to provide a more efficient utilization of experimental data, to increase weight of every animal for a more accurate estimation of potencies and to save on animal numbers 30-40%.

[Fibro-osseous lesions of the jaw and facial bones: a clinico-histologic-radiologic study of 138 cases]

A clinical-histologic-radiologic study of 138 cases of fibro-osseous lesions of the jaw and facial bones is presented. In this series, all were monostotic lesions except 8 polyostotic fibrous dysplasia. In the 130 monostotic lesions, 59 occurred in maxilla, 66 in mandible, 4 in zygoma and one in ethmoid bone. Clinically, a painless enlargement of the involved bone was the main sign. Histologically, these lesions were composed of proliferating fibrous connective tissues and various amounts of calcified tissues, but different lesion has different feature. Radiologically, fibrous dysplasia was characterized by lesions with diffuse blending. The other three tumors including ossifying fibroma, cementifying fibroma and fibro-osteoma were all represented by lesions with well delineated borders. In this article, Diagnosis of the fibro-osseous lesions and some questions about fibro-osteoma of the jaw and facial bones and osteofibrous dysplasia of long bones are discussed.