Platelet-derived microparticles may influence the development of atherosclerosis in diabetes mellitus

We investigated the association between low-density lipoprotein (LDL), triglycerides, and platelet activation in 18 patients with hypertension age 41-64 years and 18 with diabetes mellitus aged 43-70 years. Platelet P-selectin positivity and the microparticle level (indicators of activation) were both significantly higher in the diabetics than in healthy controls (P-selectin: 28.0% +/- 7.5% vs. 7.3% +/- 4.2%, P < 0.001; microparticles: 1900 +/- 966 vs. 526 +/- 158/10(4) platelets, P < 0.01). In contrast, there was no significant increase of either parameter in the patients with hypertension. Plasma microparticle levels were also significantly greater in the diabetics with high LDL levels than in those with low LDL levels (2375 +/- 949 vs. 1519 +/- 796/10(4) platelets, P < 0.05), and in those with high rather than low triglyceride levels (2188 +/- 845 vs. 1492 +/- 783/10(4) platelets, P < 0.05). However, platelet positivity for P-selectin was not significantly different between these two subgroups. Microparticle and P-selectin levels both showed no significant difference between the hypertensive patients with high and low LDL or triglyceride levels. These results suggest that platelet-derived microparticles may participate in the development or progression of atherosclerosis in patients with diabetes mellitus.

Assignment of Opsonic Values to Pneumococcal Reference Serum 007sp for Use in Opsonophagocytic Assays for 13 Serotypes

Opsonophagocytic assays (OPAs) are routinely used for assessing the immunogenicity of pneumococcal vaccines, with OPA data often being utilized for licensure of new vaccine formulations. However, no reference serum for pneumococcal OPAs is available, making evaluation of data among different laboratories difficult. This international collaboration was initiated to (i) assign consensus opsonic indexes (OIs) to FDA pneumococcal reference serum lot 007sp (here referred to as 007sp) and a panel of serum samples used for calibration of the OPA and (ii) determine if the normalization of the OPA results obtained with test samples to those obtained with 007sp decreases the variability in OPA results among laboratories. To meet these goals, six participating laboratories tested a panel of serum samples in five runs for 13 serotypes. For each serum sample, consensus OIs were obtained using a mixed-effects analysis of variance model. For the calibration serum samples, normalized consensus values were also determined on the basis of the results obtained with 007sp. For each serotype, the overall reduction in interlaboratory variability was calculated by comparing the coefficients of variation of the unadjusted and the normalized values. Normalization of the results substantially reduced the interlaboratory variability, ranging from a 15% reduction in variability for serotype 9V to a 64% reduction for serotype 7F. Normalization also increased the proportion of data within 2-fold of the consensus value from approximately 70% (average for all serotypes) to >90%. On the basis of the data obtained in this study, pneumococcal reference standard lot 007sp will likely be a useful reagent for the normalization of pneumococcal OPA results from different laboratories. The data also support the use of the 16 FDA serum samples used for calibration of the OPA as part of the initial evaluation of new assays or periodic assessment of established assays.

Botulinum toxin type A inhibits rat pyloric myoelectrical activity and substance P release in vivo

The effect of botulinum toxin type A (BTX-A) on rat pyloric myoelectrical activity in vivo and the content and distribution of substance P (SP) in pylorus were investigated, respectively, with electromyography, radioimmunoassay, and immunohistochemistry. A pair of electrodes for recording pyloric myoelectrical activity and a guide cannula for drug injection were implanted into the pylorus. The changes of pyloric myoelectrical activity were recorded followed vehicle, 10, 20, and 40 U/kg body mass of BTX-A injection. Pyloric tissues were dissected for radioimmunoassay and immunohistochemistry after recording. The 3 dosages of BTX-A injections caused the reduction of slow wave of pyloric myoelectrical activity in amplitude but not in frequency and the diminishment of spike activity in amplitude and spike burst. The inhibitory effect of 20 U/kg BTX-A was significantly different from that of 10 U/kg (p<0.05), but not from the effect of 40 U/kg administration (p>0.05). After BTX-A intrasphincteric injection, SP content was reduced in the pylorus, and cell number of SP-immunoreactivity was decreased more in myenteric nerve plexus of circular muscle and in mucosa of pylori. In conclusion, BTX-A inhibits pyloric myoelectrical slow activity in amplitude and spike activity and weakens pyloric smooth muscle contractility depending on threshold of dose or concentration. BTX-A-induced inhibition of pyloric myoelectrical activity implies a mechanism of inhibiting SP release from the autonomic and enteric nervous terminals in the pylorus.

A Leaf Inoculation Method for Detection of Xanthomonas oryzae pv. oryzicola from Rice Seed

A leaf-inoculation method for detecting Xanthomonas oryzae pv. oryzicola in rice seed was developed and tested. The method is based on inoculating leaf segments on agar with seed washings in a moist chamber. Freshness of inoculated leaf segments is maintained by addition of 75 to 100 ppm benzimidazole to the 1% water agar after sterilization. Using cells from pure cultures, the minimum inoculum concentration to initiate leaf streak lesions on the segments was found to be 10³ CFU/ml. Inoculum prepared from seeds harvested from severely infected mother plants induced lesions typical of leaf streak, followed by bacterial ooze. With 4 g of seed, the incubation period was 3.5 days and bacterial ooze appeared within 5 days. The minimum amount of seed needed to detect the bacterium based on seed washings varied according to disease severity of the mother plants. The bacteria isolated from lesions on the leaf segments were confirmed as X. oryzae pv. oryzicola after bacteriological, serological, and Biolog tests were conducted. The results confirm that the detached-leaf method is as simple and reliable as the immuno-radiometric assay and inoculation on intact pot-grown rice plants in the greenhouse.

Transient inhibition of mitochondrial function by chrysin and apigenin prolong longevity via mitohormesis in C. elegans

Mild inhibition of mitochondrial function leads to longevity. Genetic disruption of mitochondrial respiratory components either by mutation or RNAi greatly extends the lifespan in yeast, worms, and drosophila. This has given rise to the idea that pharmacologically inhibiting mitochondrial function would be a workable strategy for postponing aging. Toward this end, we used a transgenic worm strain that expresses the firefly luciferase enzyme widely to evaluate compounds by tracking real-time ATP levels. We identified chrysin and apigenin, which reduced ATP production and increased the lifespan of worms. Mechanistically, we discovered that chrysin and apigenin transiently inhibit mitochondrial respiration and induce an early ROS, and the lifespan-extending effect is dependent on transient ROS formation. We also show that AAK-2/AMPK, DAF-16/FOXO, and SKN-1/NRF-2 are required for chrysin or apigenin-mediated lifespan extension. Temporary increases in ROS levels trigger an adaptive response in a mitohormetic way, thereby increasing oxidative stress capacity and cellular metabolic adaptation, finally leading to longevity. Thus, chrysin and apigenin represent a class of compounds isolated from natural products that delay senescence and improve age-related diseases by inhibiting mitochondrial function and shed new light on the function of additional plant-derived polyphenols in enhancing health and delaying aging. Collectively, this work provides an avenue for pharmacological inhibition of mitochondrial function and the mechanism underlining their lifespan-extending properties.

Bacterial Wilt of Mulberry (Morus alba) Caused by Enterobacter cloacae in China

In August of 2006, a new bacterial disease was noted in Hangzhou mulberry orchards of Zhejiang Province, China where bacterial wilt of mulberry caused by Ralstonia solanacearum was previously reported (3). In the summer, the disease caused severe wilt, especially on 1- or 2-year-old mulberry plants, that resulted in premature plant death. Leaf wilt symptoms generally started on older leaves at the bottom of the plant and spread to the younger leaves. The leaves of infected plants became withered and dry, turned dark brown, and eventually the plants became defoliated. The root xylem of infected plants was moist and discolored with brown stripes. The phloem was asymptomatic, however, in severe infections, the phloem was decayed. The observation of wilting proceeding from the bottom of the plant to the top distinguishes this disease from bacterial wilt caused by R. solanacearum. Five bacterial strains isolated from infected mulberry plants showed characteristics similar to those of the standard reference strain of Enterobacter cloacae subsp. cloacae IBJ0611from China, but differed from R. solanacearum IBJ35, E. cancerogenus LMG2693^T, and E. cloacae subsp. dissolvens LMG2683^T from the University of Gent, Belgium in phenotypic tests, including the Biolog Identification System version 4.2 (Biolog Inc., Hayward CA), pathogenicity tests, transmission electron microscopy (TEM,KYKY-1000B, Japan) observation, and gas chromatographic analysis of fatty acid methyl esters (FAMEs) using the Microbial Identification System (MIDI Company, Newark, DE) with the aerobic bacterial library (TABA50). Isolates were gram negative, facultative anaerobic, rod shaped, 0.3 to 1.0 × 1.0 to 3.0 μm with peritrichous flagella. Colonies on nutrient agar were light yellow, smooth, circular, entire, and convex with no green fluorescent diffusible pigment on King's medium B (3). Weak hypersensitive reaction was observed on tobacco 3 days after inoculation. All five strains were identified as E. cloacae with Biolog similarity of 0.662 to 0.863 and FAMEs similarity of 0.632 to 0.701. Inoculation of 10 6-month-old intact mulberry plants of cv Husang with cell suspensions containing 10⁹ CFU/ml by pinprick at the base of the stem reproduced symptoms observed in natural infections. No symptoms were noted on the two control plants inoculated by the same method but with sterilized distilled water. The bacterium was reisolated from the symptomatic mulberry plants. E. cloacae has been reported from the United States as the cause of internal yellowing of papaya fruits (1) and rhizome rot of edible ginger (2). To our knowledge, this is the first report of mulberry wilt caused by E. cloacae in China. References: (1) K. Nishijima et al. Plant Dis. 71:1029, 1987. (2) K. Nishijima et al. Plant Dis. 88:1318, 2004. (3) L. Xu et al. Acta Phytophylacica. Sin. 34:141, 2007.

Grain Discoloration of Rice Caused by Pantoea ananatis (synonym Erwinia uredovora) in China

In the autumn of 2008, a new bacterial disease of rice was noted in paddy fields near Hangzhou, Zhejiang Province, China. The disease caused severe discoloration of rice grains on cv. Zhong-zhe-you 1 (Oryza sativa L.). It often occurred at early flowering of hybrid rice. Initially, light, rusty, water-soaked lesions appeared on the lemma or palea and then turned brown. More immature and lighter grains were observed on panicles at harvest. No bacterial ooze was observed. Ten bacterial isolates were recovered from eight samples of discolored rice grains (1). Six isolates were selected for identification. They were similar to those of the reference strain of Pantoea ananatis (Serrano, synonym Erwinia uredovora) LMG 2665^T (ATCC 33244) from Belgium in phenotypic tests based on the Biolog Microbial Identification System, version 4.2 (Biolog Inc., Hayward, CA), pathogenicity tests, gas chromatographic analysis of fatty acid methyl esters (FAME) using the Microbial Identification System (MIDI Inc, Newark, DE) with the aerobic bacterial library (TAB 5.0), and electron microscopy (TEM,KYKY-1000B, Japan). All isolates were facultatively anaerobic, gram-negative rods that measured 1.6 to 2.5 × 0.5 to 0.7 μm and had three to six peritrichous flagella. Colonies on nutrient agar were yellow and raised with smooth margins. A hypersensitive reaction was observed on tobacco (Nicotiana tobacum cv. Benshi) 24 h after inoculation. All isolates were identified as P. ananatis with Biolog similarity indices of 0.716 to 0.852 and FAME similarity indices of 0.783 to 0.903. Further identification as P. ananatis was done by 16S rDNA sequence analysis. Amplicons were produced from three strains using the universal primers (3) fD2: 5'-AGA GTT TGA TCA TGG CTC AG-3' forward primer and rP1: 5'-ACG GTT ACC TTG TTA CGA CTT-3' reverse primer and then sequenced (GenBank Accession Nos. GU324769, GU324770, and GU338399). A BlastN search of GenBank revealed that they had 97 to 98% nt identity with P. ananatis strain 3Pe76 (GenBank Accession No. EF178449). Koch's postulates were completed by spray inoculating panicles of rice cv. Zhong-zhe-you 1 at booting stage, grown in pots, with cell suspensions containing 10⁸ CFU/ml of the six strains at 25 to 29°C. Three plants were inoculated with each strain, controls were sprayed with water, and the experiment was repeated once. Three weeks after inoculation, all strains produced symptoms on panicles similar to those observed in the field. Yellow pigmented bacteria were reisolated from symptomatic panicles and their identity was confirmed by FAMEs. These results indicate that the pathogen is P. ananatis (2), which also causes leaf blight and bulb decay of onion. To our knowledge, this is the first report of rice grain discoloration caused by P. ananatis in China. The disease cycle on rice and the control strategies in the regions are being further studied. References: (1) J. Y. Luo et al. Plant Dis. 91:1363, 2007. (2) H. G. Truper and L. de Clari. Int. J. Syst. Bacteriol. 47:908, 1997. (3) W. G. Weisburg et al. J. Bacteriol. 173:697, 1991.

γ-Aminobutyric acid-mediated neurotransmission in cerebellar-hypothalamic circuit attenuates gastric mucosal injury induced by ischemia-reperfusion

BACKGROUND

Excessive greater splanchnic nerve (GSN) activation contributes to the progression of gastric ischemia-reperfusion (GI-R) injury. This study was designed to investigate the protective mechanism of cerebellar fastigial nucleus (FN) stimulation against GI-R injury.

METHODS

The GI-R injury model was induced in rats by clamping the celiac artery for 30 min, and then reperfusion for 30 min, 1, 3, 6, or 24 h, respectively.

KEY RESULTS

Microinjection of L-Glu (3, 6, 12 μg) into the FN dose-dependently attenuated GI-R injury and GSN activity. In addition, there was an enhancement of gastric mucosal blood flow in GI-R rats. Pretreatment with the glutamic acid decarboxylase antagonist into the FN, the GABAA receptor antagonist into the lateral hypothalamic area or lesion of superior cerebellar peduncle all reversed the protective effects of the FN stimulation. Furthermore, the FN stimulation reduced the TUNEL-positive gastric mucosal cell and Bax-positive gastric mucosal cell in GI-R rats.

CONCLUSIONS & INFERENCES

These results indicate that the protective effects of the FN stimulation against GI-R injury may be mediated by attenuation of the excessive GSN activation, gastric mucosal cell apoptosis, and Bax expression in GI-R rats.

Genetic structure of Culex tritaeniorhynchus (Diptera: Culicidae) based on COI DNA barcodes

Culex tritaeniorhynchus Gile is a major vector of Japanese encephalitis in China. The population genetics study is crucial as it helps understanding the epidemiological aspects of mosquito-brone diseases and improving vector control measures. Here, the genetic population structure of C. tritaeniorhynchus in the mainland China were estimated using the cytochrome c oxidase subunit 1 (COI) DNA barcodes region. 485 individuals of C. tritaeniorhynchus were collected from 38 sampling sites in 21 geographic populations in the mainland China. In total, 485 sequences were used to explore the population structure and genetic diversity. The results showed that the populations of C. tritaeniorhynchus had high haplotype diversity (Hd = 0.98, with 303 haplotypes), low nucleotide diversity (p = 0.02245) and high gene flow (Nm = 47.11) with two maternal lineages and four groups. An AMOVA indicated that 98.8% of the total variation originated from variation within populations. In addition, the population genetic structure exhibited by C. tritaeniorhynchus filling the vacant of the genetic structure in the mainland China. Human activities may also assist mosquito movement and migration. Gene flow among the populations of C. tritaeniorhynchus can facilitate the spread of insecticide resistance genes over geographical areas, and it will be a challenging for controlling the populations.

HLA and HPA typing in idiopathic thrombocytopenic purpura patients treated with Kami-kihi-to

We performed human leukocyte antigen (HLA) and human platelet antigen (HPA) in patients with Kami-kihi-to-responsive idiopathic thrombocytopenic purpura. The HLA-A2, A61 and Cw1 were significantly increased in responders compared with nonresponders, as were HLA DRB1 *0901, DRB1 *1502, and DPB1 *0501. In contrast, HLA DPB1 *0201 and DPB1 *0901 were significantly decreased in responders. The a/b genotype of HPA-2 and a/a genotype of HPA-3 were markedly increased in nonresponders, and anti-GPIb antibody was also increased. These results suggest that HLA, HPA, and anti-GP antibody studies may predict the response of idiopathic thrombocytopenic purpura to Kami-kihi-to.

Annexin V expression and membrane vesiculation during activation of leukemic cell lines

We investigated annexin V expression and membrane vesiculation during activation of four leukemic cell lines (U937, HL60, HEL, and CMK11-5) in order to determine whether annexin V had a role in the coagulation abnormalities related to malignancy. After stimulation by tissue plasminogen activator, binding of a monoclonal anti-annexin V antibody to U937 cells and HL60 cells increased in comparison with binding to control cells. Stimulation with thrombin or lipopolysaccharide also induced such an increase, but U46619 did not. Following activation of U937 and HL60 cells with thrombin and lipopolysaccharide, microparticle formation increased. Tissue plasminogen activator caused an increase of microparticles in U937 cells, but not HL60 cells. On the other hand, CMK11-5 and HEL cells did not show any increase of microparticles. These results suggest that some agonists can potently stimulate expression of prothrombinase

Survival benefit of adjuvant transcatheter arterial chemoembolization for patients with hepatocellular carcinoma after anatomical hepatectomy

BACKGROUND & AIMS

Although anatomical hepatectomy (AH) is widely used in the treatment of hepatocellular carcinoma (HCC), the prognosis is still unsatisfactory. The present study aimed to evaluate the survival benefit of adjuvant transcatheter arterial chemoembolization (TACE) for patients with HCC after AH.

METHODS

A total of 832 patients were stratified into with adjuvant TACE (443, 53.2%) and without adjuvant TACE group (389, 46.8%) AH. Propensity score matching (PSM) was performed to control for confounding factors, and multivariable Cox regression was performed to determine the independent risk factors.

RESULTS

After PSM, the results showed that the adjuvant TACE group had better overall survival (OS) and recurrence-free survival (RFS). Among the patients with tumor recurrence, adjuvant TACE was associated with a high rate of early-stage tumor at recurrence, a lower recurrence rate around the frontal margin and extrahepatic metastases, and a higher rate of receiving curative treatment. Multivariable Cox regression analysis showed that adjuvant TACE was an independent prognostic factor for OS (HR 0.673, P = 0.001) and RFS (HR 0.650, P = 0.001).

CONCLUSIONS

Patients with HCC after AH can benefit from postoperative adjuvant TACE. Therefore, adjuvant TACE should be considered for patients with a high risk of recurrence.

Specific and Sensitive Detection of Enterobacter mori Using Reliable RT-PCR

Enterobacter mori, the causal agent of bacterial wilt in mulberry, is becoming a serious disease in mulberry orchards in China. Because no effective control strategy has been devised for this disease, the reliable screening of mulberry material for latent infection became necessary. Hence, a fast polymerase chain reaction (PCR) assay for the detection of E. mori was developed in this study. The primers were designed within regions of the RNA polymerase β-subunit (rpoB) gene. The method is fast and simple and showed 100% sensitivity (no false negatives) and 100% specificity (no false positives), which was tested with 4 representative E. mori strains, 9 Enterobacter type strains, 2 strains of the other major mulberry bacterial pathogens (Ralstonia solanacearum and Pseudomonas syringae pv. mori) in China, 7 strains of other plant-associated pathogens, and 50 unidentified epiphytic bacterial isolates from mulberry plants. The real-time PCR assays reliably detected the DNA at at least 10 fg/μl and the bacterial cells at 10² CFU/ml from mulberry shoots and roots suspension. The strong positive reaction in testing of all symptomatic plants (with 100% positive) and parts of asymptomatic latent infected plant samples (with 36.4% positive) provided proof that this method is reliable and sensitive and suitable for screening plant material with latent infections of E. mori.

First Report of Bacterial Head Rot of Broccoli Caused by Pseudomonas fluorescens in China

During warm and humid periods in the winters from 2005 to 2008, head rot symptoms on broccoli (cv. Sijilv) (Brassica oleracea L. var italica Planch) were observed in commercial fields in Ningbo, Zhejiang Province, China. In agreement with the report of Cui and Harling (1), water-soaked lesions developed on the buds and then progressed into a brown-black soft rot. Longitudinal sections of the symptomatic inflorescences showed brown discoloration and rotting of the internal tissues. Broccoli production is hampered by the disease, with disease incidence ranging from 65 to 81%. Bacteria were isolated by streaking on nutrient agar (3) and individual colonies formed after 2 to 3 days of incubation at 28°C. Fifteen of thirty isolates induced hypersensitive reactions (HR) on tobacco leaves (Nicotiana tabacum cv. Samsun) within 48 h. All the HR-positive strains were fluorescent on King's medium B and the colonies were smooth, convex, entire, and round. Classical bacteriological tests indicated that the fluorescent strains were gram negative, obligate aerobes, arginine dihydrolase positive, and oxidase positive. Also, the fluorescent strains were positive for the production of levan from sucrose. Five representative strains were further characterized by the Biolog Microbial Identification System, version 4.2 (Biolog Inc., Hayward, CA) and gas chromatography of fatty acid methyl esters (FAME) using the Microbial Identification System (MIDI Inc., Newark, DE) with the aerobic bacterial library (TSBA50). The five strains were identified as Pseudomonas fluorescens with Biolog and FAME similarity indexes of 0.61 to 0.68 and 0.52 to 0.58, respectively. The 16S rRNA gene sequence of broccoli strain PFB-01 (GenBank Accession No. GQ352649) was determined according to Li et al. (2). A subsequent GenBank search showed that this sequence had 98% nucleotide identity with the type strain of P. fluorescens (ATCC 17386^T, GenBank Accession No. AF094726). Koch's postulates were completed by the inoculation of broccoli heads (cv. Sijilv) with cell suspensions (10⁷ CFU/ml) of the above five strains by spraying on the surface of subcorymbs. Each treatment had five replicates. All strains induced head rot symptoms similar to those observed in natural infections. No symptoms were noted on the control plants inoculated with sterile water. Bacteria were successfully reisolated from symptomatic heads and confirmed by the cellular fatty acid composition. To our knowledge, this is the first report in China that P. fluorescens is the causal pathogen of bacterial head rot of broccoli. References: (1) X. Cui and R. Harling. Phytopathology 96:408, 2006. (2) B. Li et al. J. Phytopathol. 154:711, 2006. (3) N. W. Schaad et al. Laboratory Guide for Identification of Plant Pathogenic Bacteria. 3rd ed. The American Phytopathological Society. St. Paul, MN, 2001.

First Report of Pear Blossom Blast Caused by Pseudomonas syringae pv. syringae in China

In the spring of 2006, a new bacterial disease was noted in pear orchards near Hangzhou, Zhejiang Province, China. The disease caused severe blossom blast on pears (Pyrus pyrifolia; cv. Cuiguan). Early symptoms of the disease included blackening of the calyx end of developing fruit, blackening of blossom clusters while leaves of affected blossom clusters appeared normal, or death of clusters consisting of both blossoms and leaves. Later, tips of twigs turned dark brown and died. No bacterial ooze was observed. Twelve bacterial isolates were recovered from ten samples of buds and blossoms. Six isolates were selected for identification. They were similar to those of the reference strains of Pseudomonas syringae pv. syringae LMG5570 and LMG 2230 from Belgium in phenotypic tests on the basis of the Biolog Microbial Identification System (version 4.2; Biolog Inc., Hayward, CA), pathogenicity tests, gas chromatographic analysis of fatty acid methyl esters (FAMEs) using the Microbial Identification System (MIDI Inc., Newark, DE) with aerobic bacterial library (TABA50), and electron microscopy (TEM, KYKY-1000B, Japan). All isolates tested were gram-negative, aerobic rods measuring 1.5 to 2.4 × 0.5 to 0.6 μm with 2 to 4 polar flagella. Fluorescent green diffusible pigment was produced on King's Medium B. Colonies were gray-white and slightly raised with smooth margins on nutrient agar. They produced levan on sucrose nutrient agar. A hypersensitive reaction was observed on tobacco cv. Benshi 24 h after inoculation. All isolates were identified as P. syringae pv. syringae with Biolog similarity index of 0.57 to 0.86 and FAME similarity index of 0.58 to 0.81. Identification as P. syringae pv. syringae was confirmed using 16S rDNA universal primers (2,3): 5'-AGA GTT TGA TCA TGG CTC AG-3' forward primer, 5'-ACG GTT ACC TTG TTA CGA CTT-3' reverse primer. The PCR fragments of the three isolates were sequenced and compared with sequences in GenBank. They had 99% similiarity with P. syringae pv. syringae 16S rRNA gene strain NCPPB 3869. Koch's postulates were conducted on buds of the original pear cultivar growing in pots and detached pear blossoms in flasks by spray inoculation with cell suspensions containing 10⁸ CFU/ml of the six isolates at 18 to 22°C with two replications. The bacteria induced symptoms on buds and blossoms similar to those observed in the field. The bacterium was reisolated from symptomatic pear buds and internal ovary tissues. P. syringae pv. syringae was first reported in England as the cause of pear blossom blast in 1914 (1). After searching all the Chinese agricultural databases and major journals (National Knowledge Infrastructure database, Vip Chinese periodical database, Chinese wanfang database, China InfoBank, Scientia Agricultura Sinica, Acta Phytopathologica Sinica, Acta Phytophylacica Sinica, and Journal of Fruit Science), to our knowledge, this is the first report of pear blossom blast caused by P. syringae pv. syringae in China. The disease cycle on pear trees and the control strategies in the regions are being further studied. References: (1) B. P. Barker et al. Ann. Appl. Biol. 1:85, 1914. (2) U. Edward et al. Nucleic Acids Res. 17:7843,1989. (3) B. Li et al. J. Phytopathol. 34:141, 2006.

Participation of alpha IIb beta 3 in platelet microparticle generation by collagen plus thrombin

We investigated the role of alpha IIb beta 3 in microparticle generation by normal and thrombasthenic platelets stimulated with collagen plus thrombin. Microparticle generation by normal platelets was scarcely inhibited by monoclonal antibodies for glycoprotein Ib and glycoprotein IX. Although one monoclonal anti-alpha IIb beta 3 antibody (NNKY1-32) partly inhibited microparticle generation, 3 other monoclonal anti-alpha IIb beta 3 antibodies had little effect. However, the combination of 4 monoclonal anti-alpha IIb beta 3 antibodies or treatment with a polyclonal anti-alpha IIb beta 3 antibody significantly inhibited microparticle generation (p < 0.05). Microparticle generation by thrombasthenic platelets also occurred after stimulation with collagen plus thrombin, although at a significantly lower level compared with normal platelets. Monoclonal antibodies for resting alpha IIb beta 3, P-selectin, activated alpha IIb beta 3 and beta 2-glycoprotein I bound to microparticles from healthy platelets. In contrast, only a monoclonal antibody for beta2-glycoprotein I bound to thrombasthenic microparticles. These results suggest that microparticle generation by collagen plus thrombin occurs via two different mechanisms which are dependent and independent of alpha IIb beta 3, respectively. The alpha IIb beta 3-dependent mechanism appears to require activation of alpha IIb beta 3.

[Electrophoretic mobility of T and B lymphocytes in bone tumor patients]

Electrophoretic mobility of peripheral blood T and B lymphocytes in bone tumor patients (malignant 24 and benign 16) was studied. Its variations associated with cellular immunity were evaluated in this paper. The electrophoretic mobility of cells was measured at 25 +/- 0.5 degrees C with a cytopherometer. The results showed that electrophoretic mobility of T lymphocytes and E-rosettes in malignant tumor patients were significantly low (P less than 0.05) as compared with that in the normal subjects, while those in the benign tumor patients were not significantly different (P greater than 0.05).

Ultrastructural localization of myeloperoxidase activity in acute monoblastic leukemia

In five patients with acute monoblastic leukemia (AMoL), the ultrastructural localization of myeloperoxidase (MPO) activity was investigated by two methods, one generally used for the detection of MPO and the other for the detection of platelet peroxidase. The MPO-positive rate achieved was lower with the former method than with the later, indicating that MPO is degraded during the fixation of AMoL cells for electron microscopy. If the ultrastructural MPO positivity of leukemic cells varies when different detection methods are used, the possibility of monocytic leukemia should be considered.

[Effectiveness of an immunization campaign with group A and C meningococcal polysaccharide vaccine in controlling an outbreak of group C meningococcal disease]

OBJECTIVE

To assess the safety, immunogenicity and efficacy of group A and C meningococcal polysaccharide vaccine (A/C MPV) in response to an outbreak of group C meningococcal disease.

METHODS

A vaccination campaign with A/C MPV was prompted 6 weeks after the use of group A MPV in Laibin city, Guangxi, where an outbreak of group C meningococcal meningitis occurred in 2002. Vaccinees were observed for local and systemic reactions after the vaccination and followed up for the meningococcal disease for 5 years. Blood samples were collected from 71 people in the epidemic and 43 in the non-epidemic areas before and 1 month after the vaccination and examined by ELISA to detect IgG antibodies to group A and C polysaccharides.

RESULTS

The vaccination coverage was 97%. No significant adverse reactions were observed. The positive rates of group C antibodies after vaccination was between 97.67% and 100% among the populations in the epidemic and non-epidemic areas, as well as among those negative and positive for group C antibodies prior to the vaccination. The geometric mean anti-C concentrations ranged 30.81 microg/ml to 37.44 microg/ml, showing no significant difference between groups. The incidence rate of meningococcal disease in students with timely immunization (218.58/100,000) dropped by 69.02%, when compared to that in those with delayed immunization (705.72/100,000). No clinical cases were identified during the follow-up period of 15,760 person-years.

CONCLUSION

The vaccination campaign with the Chinese group A/C MPV seemed successful in controlling the group C meningococcal outbreak. The vaccine was shown to be safe even administered after the group A vaccine only 6 weeks apart. It could induce high levels of antibodies in vulnerable population and significantly increase antibody levels in seropositive individuals, thus providing a protection of at least 5 years.

Bacterial Stem Rot of Poinsettia Caused by a Dickeya sp. (Pectobacterium chrysanthemi) in China

In December 2006, a rot symptom of unknown etiology was observed on stems of plants (Euphorbia pulcherrima cv. Fu-xing) at a flower nursery in the Zhejiang Province of China where we had previously reported leaf spot of poinsettia caused by Xanthomonas campestris (2). Chlorotic spots anywhere along the stem and purplish black petioles were the first noticeable symptoms. The spots rapidly coalesced, forming large irregular chlorotic areas. Petioles turned black and shriveled and affected leaves wilted. Infected tissues were soft and water soaked. Ten bacterial strains were isolated from the diseased samples and five were selected for identification. They were similar to those of the standard reference strains of Pectobacterium chrysanthemi (Dickeya sp.), LMG 2804 from Belgium and ZUPB20056 from China, in phenotypic tests based on the Biolog Microbial Identification System, version 4.2 (Biolog Inc., Hayward, CA), pathogenicity tests, gas chromatography of fatty acid methyl esters (FAME) using the Microbial Identification System (MIDI Inc, Newark, DE) with aerobic bacterial library (TABA50), and transmission electron microscopy (TEM,KYKY-1000B, Japan). All strains tested were gram-negative facultative anaerobic rods measuring 1.5 to 3.6 × 0.6 to 1.1 μm, with peritrichous flagella. Colonies were gray-white and slightly raised with smooth margins on nutrient agar. They were negative for trehalose and positive for phosphatase production and reducing substances from sucrose. A hypersensitive reaction was observed on tobacco cv. Benshi, 24 h after inoculation. All five isolates, LMG 2804, and ZUPB20056 were identified as P. chrysanthemi (Dickeya sp.) with a Biolog similarity index of 0.58 to 0.83, 0.68, and 0.72 and a FAME similarity index of 0.52 to 0.80, 0.59, and 0.70, respectively. Identification as P. chrysanthemi (Dickeya sp.) was confirmed by PCR with specific primers used by Nassar et al (3). Koch's postulates were completed with the inoculation of 12 4-month-old intact poinsettia plants of cv. Fu-xing with cell suspensions containing 10⁸ CFU/ml by a pinprick at the base of the stem. All five strains induced stem infection similar to those observed in natural infections. No symptoms were noted on the two control plants inoculated with sterilized distilled water by the same method. The bacterium was reisolated from symptomatic stems of poinsettia plants. P. chrysanthemi (Dickeya sp.) was first reported in United States as the cause of bacterial stem rot of poinsettia in 1972 (1). To our knowledge, this is the first report of poinsettia stem rot caused by P. chrysanthemi (Dickeya sp.) in China. The disease cycle and the control strategies of the bacterial stem rot of poinsettia in the regions are being further studied. References: (1) H. A. J. Hoitink et al. Plant Dis. Rep. 56:480, 1972. (2) B. Li et al. Plant Pathol. 55:293, 2006. (3) A. A. Nassar et al. Appl. Environ. Microbiol. 62:2228, 1996.

Glypican-3 protein expression in serum and tissues and its clinical significance in hepatocellular carcinoma

AIM: To investigate glypican-3 (GPC3) protein expression and its clinical significance in serum and tissues in hepatocellular carcinoma (HCC).

METHODS: Serum and tissues from 27 patients with HCC and 28 with benign liver disease were collected the day before operation. Expression of GPC3 in serum was detected by Western blotting, and expression in tissues was detected by immunohistochemistry.

RESULTS: In the 27 patients with HCC, GPC3 expression in the HCC, paracarcinomatous and non-tumor liver tissues was 81.5, 0 and 0%, respectively (HC: 23.4689, P < 0.001), and that in the serum before operation was 55.6%. There was no expression of GPC3 in the tissue and serum of the 28 patients with benign liver disease. The sensitivity, specificity and false-positive rates were 55.6, 100 and 0%, respectively, with serum GPC3 protein standard alone in the diagnosis of HCC. GPC3 protein expression in serum had no correlation with patient age or sex, alfa feta protein and hepatitis B surface antigen of HCC (P > 0.05), but was correlated with tumor size and pathological grade (P < 0.05).

CONCLUSION: GPC3 protein expression in serum and tissue in HCC is higher than in non-HCC tissue. There is also greater sensitivity and specificity, and over-expression of GPC3 in HCC serum, which may be of value for the early diagnosis of HCC.

[Effect of opioid-related gene polymorphisms on patients with high-dose opioid-tolerant cancer pain]

Objective: To investigate the relationship between single nucleotide polymorphisms of opioid-related genes and high-dose opioid tolerance in patients with cancer pain. Methods: Twenty patients (high-dose opioid tolerance group, group A) who were hospitalized in Henan Cancer Hospital from June 2016 to June 2018 and who received high-dose opioid for pain control for more than 1 week were selected as case groups (group A). Thirty patients with stage Ⅳ tumors who were hospitalized in Henan Cancer Hospital and did not have opioid tolerance were randomly selected as the control group (group B). The peripheral blood samples of two groups were taken for DNA extraction. Gene polymorphisms were detected in 15 single nucleotide polymorphisms (SNP) (rs1799971, rs754891060, rs200637194, rs1045642, rs7438135, rs7439366, rs2242480, rs1080985, rs529520, rs581111, rs2234918, rs4680, rs6276, rs3732765, rs9859538) of the nine opioid receptor-related genes (OPRM1,ABCB1,UGT2B7,CYP3A4,CYP2D6,OPRD1, COMT,DRD2,P2RY12) which most likely to affect high-dose opioid tolerance in patients with cancer pain. Results: The distribution of different genotypes of rs7438135 locus in UGT2B7 gene were statistically significant between the two groups (χ(2)=9.68, P=0.004). The difference in the distribution of the different genotypes of the rs3732765 locus of the P2RY12 gene in the two groups were at the significant edge (χ(2)=5.57, P=0.05). A correlation analysis between the relevant SNP locus and the risk of high-dose opioid tolerance in cancer patients indicated that individuals with rs7438135 GA genotype in cancer patients were at 6.19 times more likely to have high doses of opioid tolerance than individuals with AA genotypes. Conclusions: The rs7438135 locus gene polymorphism of UGT2B7 gene may be a risk predictor for high-dose opioid tolerance. The rs3732765 site of the P2RY12 gene may be a potential predictor of high-dose opioid tolerance.

Bacterial Stem Rot of Oncidium Orchid Caused by a Dickeya sp. (ex Pectobacterium chrysanthemi) in Mainland China

In December 2007, stem rot symptoms on orchids (Oncidium Gower Ramsey) were observed at a flower nursery in the Zhejiang Province of China. Initial symptoms were water-soaked lesions starting at the base of the stem. As these lesions expanded and elongated, the stem and leaf tissues became soft and watery. When examined with a microscope, cut edges of symptomatic stem and leaf tissues consistently exhibited bacterial streaming. The bacteria were isolated by streaking on nutrient agar (3). All isolates were gram-negative, facultative, anaerobic rods with peritrichous flagella. Infiltration of tobacco leaves (Nicotiana tabacum cv. Samsun) with the bacterial suspension of 10⁸ CFU/ml resulted in typical hypersensitivity reactions within 24 h. Five representative isolates were further characterized by the Biolog Microbial Identification System, version 4.2 (Biolog Inc., Hayward, CA) and gas chromatography of fatty acid methyl esters (FAME) by the Microbial Identification System (MIDI Inc., Newark, DE) with aerobic bacterial library (TSBA50). The five isolates were identified as Erwinia chrysanthemi (Pectobacterium chrysanthemi) with a Biolog and FAME similarity index of 0.81 to 0.88 and 0.62 to 0.75, respectively. The transfer of P. chrysamthemi to a novel genus, Dickeya gen. nov., was recently proposed (2). The almost complete 16S rDNA sequence from Oncidium isolate SCH-01 (1,604 bp; EMBL Accession No. FM946179) was determined according to the method of Li et al. (1). A subsequent GenBank search showed that this isolate is 98% identical to that of type strain CFBP 1269T of Dickeya dadantii (EMBL Accession No. AF520707) and CFBP 1200T of Dickeya dianthicola (EMBL Accession No. AF520708). Nevertheless, species identification within genus Dickeya is still difficult since only a limited number of strains of each species have been characterized fully. Koch's postulates were completed with the inoculation of Oncidium seedlings with cell suspensions (10⁸ CFU/ml) by a pinprick at the base of the stem. All five representative isolates induced stem rot similar to that observed in natural infections. No symptoms were noted on the control plants inoculated with sterilized distilled water by the same method. The bacterium was reisolated from symptomatic stems of Oncidium plants. To our knowledge, this is the first report of stem rot on Oncidium orchid in Mainland China caused by the bacterium formerly referred to as P. chrysanthemi, now proposed as Dickeya sp. References: (1) B. Li et al. J. Phytopathol. 154:711, 2006. (2) R. Samson et al. Int. J. Syst. Evol. Microbiol. 55:1415, 2005. (3) N. W. Schaad et al. Laboratory Guide for Identification of Plant Pathogenic Bacteria. 3rd ed. The American Phytopathological Society. St. Paul, MN, 2001.

Radiofrequency ablation combined with immunotherapy to treat hepatocellular carcinoma: a comprehensive review

BACKGROUND AND AIM

Hepatocellular carcinoma (HCC) is a highly immunogenic tumor and the third leading cause of cancer-related deaths worldwide with an increasing incidence. Therefore, the combination of immunotherapy with other approaches, such as anti-angiogenic agents and local area therapy, has become a new strategy for HCC treatment.

METHODS

We searched PubMed and Web of Science and extracted publications relating to the radiofrequency ablation (RFA) and immunotherapy. The search terms were: "radiofrequency ablation", "immunotherapy" and "hepatocellular carcinoma", and manual searches of eligible articles from literature reference lists were performed. We then thoroughly reviewed the literature on ablation combined with immunotherapy for HCC, analyzed the relevant mechanism, and explored the safety and effectiveness of this form of combination therapy.

RESULTS

RFA combined with immunotherapy in HCC is reported to have good efficacy and controllable safety. On the one hand, RFA can induce the immunogenic substances including Ficolin-3, IL-1 and heat shock protein and regulate the immune cells by mediating the Th1/Th2 ratio, increasing Th17 cells, etc. On the other hand, RFA treatment can lead to tumor immune microenvironment reconstruction, increasing the proportion of functional T cells and upregulate PD-1 in T cells in distant tumors without RFA. This combined strategy has the ability to enhance the anti-tumor immune response through synergies, significantly reduce the risk of recurrence and improve survival.

CONCLUSIONS

RFA combined with immunotherapy yields a good synergistic effect: it can further strengthen anti-tumor response, delay distant tumor growth, reduce tumor recurrence and metastasis, providing new options for HCC systemic treatment.