A survey of phenotype distribution of subgroup A2, blood groups MNS, P, and Kell in the Kazak nationality living in northern Xinjiang of China

The research was undertaken to study the phenotypic polymorphisms of the subgroup A2, blood groups MNS, P, and Kell in the Kazakh population in northern Xinjiang, China and establish data on rare blood group antigens in the Kazakh population, in order to provide references for clinical blood transfusion safety and prevention of hemolytic disease of the new born. In this study, 6,862 unrelated Kazakh individuals in northern Xinjiang were randomly selected, and their blood samples were collected for serological testing. The antigens of A, B, A1, M, N, P1 and K were detected by serological saline tube method, and the antigens of S, s, and k were detected by the microcolumn gel antiglobulin card method. The results were as follows: ① The detection rates of subgroup A2 in group A and group AB were 7.08% and 21.79%, respectively; ② The allele frequencies of the blood groups MNS, P and Kell were M=0.5668, N=0.4332, S=0.1860, s= 0.8140, P1=0.2848, P2=0.7152, K1=0.0096, K2=0.9904. The observed values and expected values of frequency distribution of genotypes were compared by χ² test, which conformed to the Hardy-Weinberg genetic law (P>0.05); ③ Fourteen cases of S^-s^- rare phenotype were detected in MNS blood group system, with a frequency of 1.16%; ④ The frequency of K antigen in the Kell blood group system was 1.92%. One case of rare KK homozygote was detected, with a frequency of 0.034%. Our study suggested that the distribution of gene frequency of subgroup A2, blood groups MNS, P and Kell in the Kazakh population in northern Xinjiang has its own characteristics, and their blood group MNS has unique genotypes. The positive rate of K antigen of blood group Kell in the Kazakh population was significantly higher than Chinese Han population.     

Comparative analysis of antibody responses to SARS-CoV-2 in various populations

This paper aimed to analyze antibody responses to SARS-CoV-2 in various populations. Two hundred and six COVID-19 patients, 46 convalescent patients, and 270 healthy population were enrolled. Antibodies against nucleocapsid protein (N) and spike protein''s receptor-binding domain (RBD), and neutralizing antibody were detected. The results demonstrated both anti-N and anti-RBD antibodies could be detected in about 80% of COVID-19 patients and 90% of convalescent patients, while no antibodies could be detected in some convalescents and patients even after 14 days post-onset of symptoms. The level of anti-RBD antibody strongly correlated with the neutralizing activity of sera from these two cohorts. The titer of neutralizing antibody was lower in convalescents than that in active COVID-19 patients. In addition, the titer of neutralizing antibody was less than 1:80 in none of the severe COVID-19 patients, 18.8% in non-severe COVID-19 patients, and 32.6% in convalescents. The study suggests that the level of anti-RBD antibody is closely related to neutralization activity in COVID-19 patients and convalescents. Some SARS-CoV-2-infected cases trigger a weak antiviral immune response, and the level of neutralizing antibody may have a faster decay rate.     

闽南地区TT病毒的变异及经输血传播的初步证据

TT virus(TTV)DNA was tested by nested-PCR from sera of hepatitis patients and volunteer blood donors in Minnan area. The amplified segment was a 189 base pair region in TTV ORF2. A total of six sequences were obtained from three non-A to G hepatits patients and two from volunteer blood donors. The sequences were found to be with 82.9% to 99.3% homology to TTV Japanese strain and Chinese strain. The divergence of sequence in these six segments varied from 0.7% to 17.1%, which indicated that the TTV had been existing for a long time in this area. In the serum of a non-A to G hepatitis patient who was negative for TTV DNA in the 14th day of disease course turned to be positive in the 30th day, two TTV sequences were obtained which showed 92.1% nucleotide homology. It indicated that different TTV strains can co exist in the same person. This patient's blood had been transfused ten times between the collection of his TTV negative sample and his positive serum sample. Seven of the blood donors were traced and sampled for sera, of which three were positive for TTV. For all 161 patients tested, the history of exposure to blood products was associated with an increased risk of TTV infection(relative risk, 3.0; 95% confidence intervals, 1.89～4.81).     

Mammalian cell display for rapid screening scFv antibody therapy

Human antibodies are beginning to draw attention for use in immune gene therapy. The efficient generation of effective therapeutic monoclonal antibodies suitable for the treatment of cancers and infectious diseases would be enormously valuable. Antibody display methods are increasingly used to screen human monoclonal antibodies. Here we report the construction of a mammalian cell display method derived from a naive antibody repertoire, for which human single- chain variable fragments （scFv） have been transiently dis- played on 293T cell surfaces based on a pDisplay vector. The sizes of the current pDisplay-scFv antibody repertoires have been estimated to be 0.74 × 10^7. An immunoblot assay confirmed the expression of the scFv antibody library. The subceilular distribution of ErbB3-scFv expression plasmid facilitated the display of ErbB3 scFv on the cell membrane surface and the efficiency of the display was evaluated by fluorescence-activated cell sorting. This method of mamma- lian cell display was verified by successfully screening ErbB3 scFv candidates. A published scFv control was used to confirm the feasibility of the ErbB3 scFv screening process. Three ErbB3 scFv candidates were produced and they were found to have affinity similar to the published scFv candidate. Thus, the present screening system provided an optimal alternative for rapid acquisition of a novel candi- date scFv sequence to target genes with high affinity in vitro.     

圈养小熊猫育幼行为的初步观察

Nursing behaviors of the captive md pandas were quantitatively studied by focal sampling methods in Chengdu Research Base of Giant Panda Breeding from Jldy to August, 2000. The results indicated that frequencies of activity and rest were low in the first three days after birth, and became higher as time went by. The frequency of licking cub was higher in the first day after birth and deserting cub was only observed in the seventh day. Frequencies of some behaviors, such as rest, licking cub, cherishing cub,sniffing cub, returning to shed and deserting cub, differed sioaificantly in different phases of the first month after birth. Frequencies of licking cub, cherishing cub, sniffing cub and returning to shed were significantly higher in the pre-nursing period than in the midnursing and post-nursing periods. However, frequencies of rest and deserting cub were sioaificantly higher in the post-nursing period than in the per-nursing and mid-nursing periods. The degree of maternal behaviors can be inferred from degree that the mother exposes her babies to the envim~unent and the time that the mother leaves her shed.     

Analysis of plateletpheresis donor deferral rate in family replacement donors and volunteer donors: A brief review of the China Chongqing area

In order to ensure an adequate and safe blood supply, the plateletpheresis donor deferral rate in family replacement donors and volunteer donors were analyzed in this study. The study was undertaken in Chongqing Blood Center, China. Nucleic acid testing (NAT) and ELISA were applied to assess the hepatitis B virus surface antigen (HBsAg), antibodies against hepatitis C virus (anti-HCV), human immunodeficiency virus (HIV) and Treponema palladium（TP）in plateletpheresis donors. From January 2015 to December 2016, a total of 17,342 plateletpheresis donors in Chongqing blood center were enrolled in this study. Among the 3,642 plateletpheresis donors, 21.00% were younger than 25, followed by 26–35 years group (41.19%), 36-45 years group (22.46%), 46-55 years group (13.97%) and 56-60 years group (1.38%). Replacement and voluntary donors contributed 5,305 (30.59%) and 12,037 (69.41%), respectively. Among all the plateletpheresis donors, 194 (1.12%) were deferred because of seropositive serology. Replacement and voluntary deferred donors comprised 109 (2.05%) and 85 (0.68%), respectively (P＜0.05). Among the deferred donors, 194 (1.12%) were seropositive for HBsAg (0.44%), followed by anti-HCV (0.28%), TP (0.24%) and HIV (0.15%). Prevalence deferred females contributed 67 (1.60%), while males contributed 127 (0.97%) of the deferred cases, respectively (P＜0.05). Deferral rate was highest among 46-55 years group (1.65%) followed by 36-45 years group (1.63%), The other groups were less than 1%. It is necessary to reduce family replacement donors and replace them with regular volunteer donors, and to improve blood donor retention strategies to boost the regular blood donors’ motivating. In addition to increasing and maintaining volunteer supply, it is desirable to keep the deferral rate at a low level, to ensure an adequate and safe blood supply.     

Determination of Mercury and Methylmercury in Hair of the Czech Children’s Population

The developed method for mercury speciation analysis has been validated and used for the biomonitoring study of mercury species in human hair. Statistical evaluation proved the reliability of simplified determination of inorganic mercury (difference between total mercury and methylmercury). The results of the validation showed that the method is very well suitable for the determination of both species of mercury in hair for biomonitoring purposes. Non-exposed schoolchildren from three areas in the western and central part of the Czech Republic were chosen as the target group. Tenth of a microgram per gram of the total mercury were generally found in the analyzed hair; values higher than 1 μg g⁻¹ were detected only exceptionally. Comparable results were obtained for two western areas and differed significantly from those for the third area located in the central part of the Czech Republic. In the areas examined, the mean methylmercury contents amounted to 23–46% of the total mercury in the hair. The results confirm an assumption that exposure to mercury does not pose a significant risk to the population in the Czech Republic.     

Immunological dynamics in response to two anthrax vaccines in mice

In order to understand the variation of humoral and cellular immune responses to A16R live spore and AVA vaccine and to identify efficient immunological parameters for the early evaluation of post immu- nization in mice, we dynamically monitored the antibody production and cellular responses after the vaccination of Balb/C mice with the anthrax vaccines. The results show that both anti-AVA and anti-Spore antibodies were detectable in the A16R live spore vaccinated group while high titers of anti-AVA antibodies but not anti-Spore antibodies existed in the AVA-immunized group. IgG1 and IgG2 were the major subtypes of IgG in both of the two groups. However, the IgG2a level was significantly higher in the A16R group than in the AVA group. At the cellular level, responses of antigen-specific TH2, TH1 and plasma cells were detected. The peripheral TH2 responses could be seen on day 5 after vac- cination, and remained at a high level throughout the experiment (from day 5 post primary immuniza- tion to day 60 post the tertiary immunization); the TH1 responses to A16R vaccine appeared on day 5, while the responses to AVA could only be detected by day 7 after the secondary immunization; a low level of TH1 responses could be observed at the end of the experiment. Antigen-specific plasma cells could be found in the peripheral blood of both the immunized groups, however, the responses in the A16R group appeared earlier, lasted longer, and shown an ascending tendency until the end of the ex- periment when the plasma cell responses in the AVA group were reduced to a very low level. The re- sults suggest that the multiple antigen containing A16R live spore vaccine induces better immune re- sponses than AVA. Combined with serum antibody titers, TH2, TH1 and plasma cell responses could be used as immunological parameters for the evaluation of vaccine efficacy. These findings may afford new insight into the early evaluation of vaccination as well as being a powerful strategy for vaccine development.     

Which RhD alleles are risk factors stimulating allo- anti-D?

The aim of this study was to identify the specific RhD alleles that are risk factors for stimulating allo-anti-D and develop a precise strategy for blood transfusion. To confirm the D phenotype, red blood cells suspended in saline should react to serological anti-D from three manufacturers. An antibody screen test, a saline phase test and a micro-column test were conducted to identify allo-anti-D and other allo-antibodies. RhD alleles were genotyped by PCR using sequence-specific primers. Seven hundred subjects who were either pregnant or had undergone transfusion were enrolled in our study; however, 28 samples were excluded because their RhD alleles were normal, as revealed by tests using genotyping kits. A total of 498 cases (74.1%) were RhD-null (lacking exons 1–10 of RhD), 336 were DEL RhD 1227A (20.2%), and 38 were RHD-CE (2-9) -D (5.6%). There were 136 cases (20.2%) with allo-anti-D among the 672 cases, with an allo-anti-D prevalence of 126 cases (25.3%) in 498 cases that were RhD-null, followed by 10 cases (26.3%) among 38 cases with RHD-CE (2-9) -D, and none in 366 cases with RhD1227A. RhD genetic polymorphism was observed in RhD-negative individuals. We concluded that RhD-null and partial D are risk factors for alloimmunization to the D antigen and should be transfused with Rh-negative blood. RHD1227A recipients can be transfused with RhD-positive blood. Pregnant women with the d/d and D-CE(2-9)-D alleles require appropriate anti-D prophylaxis and RhD1227A may induce a higher tolerance.     

Dynamic culture improves MSC adhesion on freeze-dried bone as a scaffold for bone engineering

AIM:To investigate the interaction between mesenchymal stem cells(MSCs) and bone grafts using two different cultivation methods:static and dynamic.METHODS:MSCs were isolated from rat bone marrow.MSC culture was analyzed according to the morphology,cell differentiation potential,and surface molecular markers.Before cell culture,freeze-dried bone(FDB) was maintained in culture for 3 d in order to verify culture medium pH.MSCs were co-cultured with FDB using two different cultivation methods:static co-culture(two-dimensional) and dynamic co-culture(threedimensional).After 24 h of cultivation by dynamic or static methods,histological analysis of Cell adhesion on FDB was performed.Cell viability was assessed by the Trypan Blue exclusion method on days 0,3 and 6 after dynamic or static culture.Adherent cells were detached from FDB surface,stained with Trypan Blue,and quantified to determine whether the cells remained on the graft surface in prolonged non-dynamic culture.Statistical analyses were performed with SPSS and a P < 0.05 was considered significant.RESULTS:The results showed a clear potential for adipogenic and osteogenic differentiation of MSC cultures.Rat MSCs were positive for CD44,CD90 and CD29 and negative for CD34,CD45 and CD11bc.FDBs were maintained in culture for 3 d and the results showed there was no significant variation in the culture medium pH with FDB compared to pure medium pH(P > 0.05).In histological analysis,there was a significant difference in the amount of adhered cells on FDB between the two cultivation methods(P < 0.05).The MSCs in the dynamic co-culture method demonstrated greater adhesion on the bone surface than in static co-culture method.On day 0,the cell viability in the dynamic system was significantly higher than in the static system(P < 0.05).There was a statistical difference in cell viability between days 0,3 and 6 after dynamic culture(P < 0.05).In static culture,cell viability on day 6 was significantly lower than on day 3 and 0(P < 0.05).CONCLUSION:An alternative cultivation method was developed to improve the MSCs adhesion on FDB,demonstrating that dynamic co-culture provides a superior environment over static conditions.     

Spatial and temporal distribution patterns of nitrogen in marsh soils from an inland alkaline wetland – A case study of Fulaowenpao wetland, China

Samples of surface (0–10 cm) and subsurface soils (10–20 cm) were collected using a grid sampling method in July and September in order to study the spatial and temporal distribution patterns of all forms of nitrogen and total nitrogen (TN) and the relationships between nitrogen concentrations and selected soil properties in Fulaowenpao wetland, a typical inland alkaline wetland. Results showed that there existed obvious heterogeneity at spatial and temporal scales. Generally, higher spatial variability for nitrate nitrogen (NO₃^-–N), ammonium nitrogen (NH₄⁺–N) and available nitrogen (AN) were observed compared to organic nitrogen (Org-N) and TN. At the spatial scale, concentrations of NO₃^-–N, NH₄⁺–N and AN in surface soils were higher than those in subsurface soils, but no significant differences were observed between both soil layers (p < 0.05). However, concentrations of Org-N and TN were significantly higher in surface soils compared to subsurface soils (p < 0.05), and both of them had similar spatial distribution patterns. At the temporal scale, with the exception of NH₄⁺–N in both soil layers and NO₃^-–N in subsurface soils, concentrations of all the other forms of nitrogen and TN were generally higher in September than them in July, while there were no significant differences between both sampling periods (p < 0.05) except for AN (p < 0.01) in both soil layers. Correlation analysis showed that AN, Org-N and TN were significantly and positively correlated with soil organic matter, total phosphorous, and clay contents, while they were significantly negatively correlated with soil pH values; NO₃^-–N was also correlated with soil organic matter and total phosphorous, however, NH₄⁺–N was only closely lined to water contents.     

Detection and Genetic Characterization of Rabies Virus from Human Patients

Saliva and blood were collected from two patients who had not received post exposure prophylaxis in the cities of Wenzhou and Xinning respectively. Both patients were confirmed as positive for rabies by detection of rabies virus specific nucleoprotein antibodies in the sera by Western Blot. However, rabies virus specific RNA was only identified in the saliva collected from the patient in Wenzhou. Furthermore, the isolate Zhejiang Wz0 (H) was obtained by inoculating one-day-old suckling mice. Both nucleoprotein (N) and glycoprotein (G) genes from the isolate were amplified by RT-PCR and sequenced. Phylogenetic analysis indicated that the isolate belonged to classic rabies virus, and shared a higher homology with the street viruses from dogs in the main endemic areas in China and the street virus from dogs in Indonesia than with other known strains. Further comparison of the deduced amino acid sequences between the isolate and the vaccine strains used in China showed that the virus had a higher level of homology with the vaccine strain CTN than with the other vaccine strains (3aG, PV, PM and ERA). In particular, amino acid residues substitutions located in antigenic site Ⅲ in the G protein, which could react with the neutralizing antibodies, were observed. These results suggested that the virus belonged to the classic rabies virus, and both N and G genes diverged from the current vaccine strains used in China at either the nucleotide or the amino acid level.     

Coagulation status detection in breast cancer patients by using thrombelastography

Many cancer patients are known to present in a hypercoagulable state, meaning an increased risk of thrombosis. To investigate hypercoagulable state in breast cancer (BC) patients, their coagulation status was compared with a benign disease group (control). The BC patients were divided into earlier stage (stage I and stage Ⅱ ) and later stage (stage Ⅲ and stage Ⅳ ). Thrombelastography (TEG) and other traditional coagulation tests were performed. The results showed that prothrombin time (PT) was significantly shortened and the levels of D-dimer, fibrinogen (Fib) and platelets (PLT) were significantly increased in the traditional BC group test (P< 0.05). According to TEG detection, the average level of blood clot formation time (K) was significantly lower, while the Angle, MA and CI were significantly higher in the BC group than those in benign disease group (P< 0.05). There were 5 cases of lower extremity venous thrombosis in the breast cancer patients, coinciding with hypercoagulable state. The results showed that the BC patients had an increased hypercoagulable state, with hypercoagulability becoming more obvious in advanced stages. This study suggests that BC patients have an increased tendency for clot formation, and TEG monitoring could be a useful tool to predict the risk of thrombosis for clinical prevention and treatment.     

No relation between ACEml/D polymorphism and high altitude pulmonary edema in the Han Chinese

Objectives To explore whether the angiotensin T -converting enzyme （ACE） I/D （insertion/ deletion） polymorphism is associated with the susceptibility to high altitude pulmonary edema （HAPE） in the Han Chinese. Methods One hundred and forty-seven HAPE-p （HAPE patients） and 193 HAPE-r （HAPE resistants） were enrolled from the Yushu earthquake reconstruction workers in Qinghai province where the altitude is over 3 500 m above sea level. Blood samples were collected from each of the HAPE-p and HAPE-r groups. Information about physiological phenotypes was obtained via fieldwork investigation. The ACE-I/D polymorphism in HAPE-p and HAPE-r was detected by polymerase chain reaction （PCR）. Results The SaO2 was significantly lower while HR was significantly higher in HAPE-p group than those in HAPE-r group. The genotype frequencies of ACE-I/D for II, ID, DD in HAPE-r and HAPE-p groups were 0.430, 0.446, 0.124 and 0.435, 0.469, 0.095, respectively, the allelic frequencies of I and D were 0.650, 0.350 and 0.670, 0.330, respectively. The OR of ID, DD and D alleles relative to II for HAPE was 0.961 （0.610-1.514）, 1.322 （0.634-2.758） and 1.080 （0.783-1.489）. There was no significant difference of the genotypic and the allelic frequencies in ACE-I/D polymorphism between HAPE-p and HAPE-r groups. Conclusions There is no relation between ACE-I/D polymorphism and HAPE in the Han Chinese.     

SPATIAL DISTRIBUTION OF ZOOPLANKTON IN THE MAIN STEM OF THE MIDDLE YANGTZE RIVER北大核心CSCD

To better understand zooplankton distribution and its relationship with the physical-chemical factors in middle Yangtze River, we collected 20 zooplankton samples from segments at Yichang, Jingzhou, Yueyang, Wuhan and Hukou in October, 2016. A total of 23 species that belong to 13 families and 14 genera were identified, among which 16 species belong to Rotifera, 4 to Copepoda and 3 to Cladocera. Among the five segments, the highest number of zooplankton species was detected at Hukou (9 species), while the lowest was at Yueyang (5 species). The average density at Wuhan (10.94±5.81) ind./L was higher than that at Hukou and the other segments. Rotifers (3.41±0.21) ind./L were dominant in the zooplanktonic community, and Keratella valga, Synchacta atylata and Keratella cochlearis were the dominant species. The average density of copepods (mainly nauplius) was (0.75±0.07) ind./L. Cladocera had the lowest average density. Similarly, the zooplankton biomass at Wuhan was also higher than that at Hukou and the other three segments. Comparing with studies at other segments of Yangtze River, we detected lower zooplankton diversity in our investigation. Spearman correlations indicated that the biomass and diversity of zooplankton were significantly and positively correlated (P<0.05) to chlorophyll a. © 2019, Institute of Hydrobiology, Chinese Academy of Sciences. All rights reserved.     

The aerobic dechlorination activities of two bacterial species isolated from a refuse dumpsite in Nigeria

Two bacterial species isolated using enrichment culture techniques from the topsoil of a main refuse dumpsite in Nigeria were assessed for their dehalogenation potentials. The bacterial isolates were identified as belonging to the Bacillus and Pseudomonas genera. Axenic cultures of the isolates utilized monochloroacetic acid (MCA), trichloroacetic acid (TCA), trichloromethane (CHCl₃) and tetrachloromethane (CCl₄) as the sole source of carbon for growth up to a final substrate concentration of 0.1% (w/v). The mean generation times of the isolates in all the growth media ranged significantly (P<0.05) from 2.41 to 10.04 h and were generally higher than that observed in glucose medium (1.46–1.51 h). The numbers of the chloride atoms in the different organochlorides were negatively correlated with the ability of the organisms to degrade the compounds. Dehalogenase specific activities of the cell-mediated cultures ranged from 0.1 to 0.96 μg ml^–1 chloride release (mg protein)^–1 h^–1 and were significantly (P <0.05) higher than that of the cell-free extract [0.09–0.8 μg ml^–1 chloride release (mg protein)^–1 h^–1]. The optimal pH of the dehalogenase activity was found to be 8.0, and the optimal temperature was between 30 and 35 °C. Electronic Publication     

Clinical strategies for differentiating IgG4-related cholecystitis from gallbladder carcinoma to avoid unnecessary surgical resection

Immunoglobulin G4(IgG4)-related cholecystitis(IgG4-C) is often difficult to distinguish from gallbladder carcinoma(GBC).This study aimed to determine a practical strategy for differentiating between IgG4-C and GBC to avoid unnecessary surgical resection. The expression of IgG4 in the gallbladder was detected by immunohistochemistry. The clinicopathological and radiological characteristics of IgG4-C patients and GBC patients were analyzed retrospectively. Immunohistochemistry revealed that IgG4 was upregulated in the plasma cells of IgG4-C tissues. The median serum total bilirubin levels were significantly higher in the patients with IgG4-C than in those with GBC(45.8 μmol L~(-1) vs. 29.9 μmol L~(-1)). The serum γ-GGT levels were higher in IgG4-C patients than in GBC patients, whereas the serum levels of CA125 were significantly higher in GBC patients than in IgG4-C patients. The imaging scans were helpful for differentiating IgG4-C from GBC based on the presence of a layered pattern and Rokitansky-Aschoff sinuses in the gallbladder wall. There were no statistically significant differences in age,presence of abdominal pain, level of emaciation between the two groups. Our study demonstrated that the combination of imaging with serum total bilirubin, γ-GGTand CA125 levels can offer added preoperative diagnostic value and reduce the rate of IgG4-C misdiagnosis.     

Autoantibody against Cardiac β1-Adrenoceptor Induces Apoptosis in Cultured Neonatal Rat Cardiomyocytes

To clarify whether apoptosis is involved in the injury processes induced by autoantibodyagainst cardiac β_1-adrenoceptor,we investigated the biological and apoptotic effects of antibodies on culturedneonatal rat cardiomyocytes.Wistar rats were immunized with peptides corresponding to the second extra-cellular loop of the β_1-adrenoceptor to induce the production of anti-β_1-adrenoceptor antibodies in the sera.Immunoglobulin(Ig)G in the sera was detected using synthetic antigen enzyme-linked immunosorbentassay and purified using the diethylaminoethyl cellulose ion exchange technique.Apoptosis of cardiomyo-cytes was evaluated using agarose gel electrophoresis and flow cytometry.Our results showed that thepositive serum IgG greatly increased the beating rates of cardiomyocytes and showed an"agonist-like"activity.Furthermore,positive serum IgG induced cardiomyocyte apoptosis after treatment with β_1-adrenoceptor overstimulation for 48h.The effects of monoclonal antibody against β_-adrenoceptor werealso found to be similar to those of positive serum IgG.It was suggested that the autoantibody could inducecardiomyocyte apoptosis by excessive stimulation of β_1-adrenoceptor.     

Spatial and temporal distribution patterns of nitrogen in marsh soils from an inland alkaline wetland – A case study of Fulaowenpao wetland, China

Samples of surface (0–10 cm) and subsurface soils (10–20 cm) were collected using a grid sampling method in July and September in order to study the spatial and temporal distribution patterns of all forms of nitrogen and total nitrogen (TN) and the relationships between nitrogen concentrations and selected soil properties in Fulaowenpao wetland, a typical inland alkaline wetland. Results showed that there existed obvious heterogeneity at spatial and temporal scales. Generally, higher spatial variability for nitrate nitrogen (NO₃^-–N), ammonium nitrogen (NH₄⁺–N) and available nitrogen (AN) were observed compared to organic nitrogen (Org-N) and TN. At the spatial scale, concentrations of NO₃^-–N, NH₄⁺–N and AN in surface soils were higher than those in subsurface soils, but no significant differences were observed between both soil layers (p < 0.05). However, concentrations of Org-N and TN were significantly higher in surface soils compared to subsurface soils (p < 0.05), and both of them had similar spatial distribution patterns. At the temporal scale, with the exception of NH₄⁺–N in both soil layers and NO₃^-–N in subsurface soils, concentrations of all the other forms of nitrogen and TN were generally higher in September than them in July, while there were no significant differences between both sampling periods (p < 0.05) except for AN (p < 0.01) in both soil layers. Correlation analysis showed that AN, Org-N and TN were significantly and positively correlated with soil organic matter, total phosphorous, and clay contents, while they were significantly negatively correlated with soil pH values; NO₃^-–N was also correlated with soil organic matter and total phosphorous, however, NH₄⁺–N was only closely lined to water contents.     

Generation and characterization of novel stromal specific antibodies

Rheumatoid synovial fibroblasts were used as an immunogen to produce monoclonal antibodies selected for their reactivity with stromal cell antigens. Mice were immunised with low passage whole cell preparations and the subsequent hybridomas were screened by immunohistochemistry on rheumatoid synovium and tonsil sections. The aim was to identify those antibodies that recognised antigens that were restricted to stromal cells and were not expressed on CD45 positive leucocytes. A significant number of antibodies detected antigen that identified endothelial cells. These antibodies were further characterised to determine whether the vessels identified by these antibodies were vascular or lymphatic. From five fusions clones were identified with predominant reactivity with： 1） fibroblasts and endothelial cells; or 2） broad stromal elements （fibroblast, endothelium, epithelium, follicular dendritic cells）. A fibroblast-specific antibody that did not also identify vessels was not generated. Examples of each reactivity pattern are discussed.