[Differential diagnosis between pulmonary artery sarcoma and central chronic pulmonary thromboembolism:a preliminary study on CT signs].

Objective: To improve the diagnostic accuracy of pulmonary artery sarcoma, and to distinguish it from central chronic pulmonary thromboembolism using CT scans. Methods: In this retrospective study, two groups of pulmonary artery sarcoma (PAS group) and central chronic pulmonary thromboembolism (central CPTE group) confirmed by pathology at our hospital between August 2009 and July 2019 were enrolled, clinical features and pre-operative CT pulmonary artery manifestation were collected, and the key points of differential diagnosis were summarized. Results: The study was composed of 13 cases in the PAS group including 10 males (76.9%), with an average age of (45.4±15.5) years. There were 19 patients in the central CPTE group including 14 males (73.7%), with an average age of (38.6±14.1) years. There were no significant differences in gender and age between the two groups. Deep venous thrombosis in the lower extremities was significantly higher in the central CPTE group than in the PAS group (7/19 vs. 0/13, P=0.025), and the N-terminal pro-brain natriuretic peptide value was higher in the central CPTE group than in the PAS group [674.50(261.70-1 977.70) vs. 66.00(28.10-505.50),P=0.001]. In CT pulmonary angiography, the involvement of the main pulmonary artery, and the proximal lesion showing an acute angle to the pulmonary artery wall were more common in the PAS group [11(84.6%) vs. 5(26.3%), P=0.003; 11(84.6%) vs. 2(10.5%), P<0.001, respectively]. The swelling index of the main pulmonary and the left/right main pulmonary arteries in the PAS group were significantly higher, as well as the dilatation in the lobar and segmental pulmonary arteries [1.19±0.17 vs. 0.99±0.19,P=0.006, 10(76.9%) vs. 2(10.5%), P<0.001, respectively]. The right ventricular transverse diameter/left ventricular transverse diameter (RVd/LVd) and pulmonary artery diameter/ascending aortic diameter ratio (Pad/Aod) were significantly lower in PAS group than those in the central CPTE group (0.97±0.19 vs. 1.23±0.35,P=0.020; 0.98±0.25 vs. 1.15±0.20,P=0.039). Conclusions: In CT pulmonary angiography, filling defects involving the main pulmonary artery and showing expansive growth were highly suggestive of pulmonary artery sarcoma. The history of deep venous thrombosis of the lower extremities was helpful for the diagnosis of chronic pulmonary embolism.

[Quantitative myocardial perfusion parameters in subjects without coronary artery lesions based on computed tomography dynamic myocardial perfusion imaging].

Objective: To determinate the range of quantitative myocardial perfusion parameters (MBF, MBV) in subjects without coronary artery lesions by dynamic computed tomography myocardial perfusion imaging (CTP). Methods: Subjects with occasional chest tightness or family history of coronary artery disease coming to Fuwai Hospital underwent coronary computed tomography angiography (CCTA) were prospectively enrolled. A total of 34 subjects [mean age (50±7) years, range from 33 to 65 years; 15 male and 19 female] were enrolled. Coronary lesions were not confirmed in any subjects using CCTA and volunteered for stress and rest dynamic CTP examination. MBF and MBV values were calculated in each myocardial segment using a 17-segment model. The global ranges of MBF and MBV were analyzed, and the gender variability and regional variability were compared. Results: The mean global MBF and MBV at rest and under stress were (115.5±27.4) ml·100 g-1·min-1, (212.8±40.8) ml·100 g-1·min-1 and (17.6±4.0) ml/100 g, (25.8±4.6) ml/100 g, respectively. The absolute and resolute reserves of MBF and MBV [(102.8±41.5) ml·100 g-1·min-1, 107.7%±52.5%; (9.3±5.2) ml/100 g, 62.1%±47.4%] were highest in the right coronary artery territory, but without any significant differences. The stress MBF and absolute reserve of MBF in females were higher than those of males [(228.6±39.9) ml·100 g-1·min-1, (113.3±46.2) ml·100 g-1·min-1; (192.8±33.4) ml·100 g-1·min-1, (77.0±41.2) ml·100 g-1·min-1] (both P<0.05). The MBF resolute reserve, rest MBV, stress MBV and MBV absolute and resolute reserves were higher in females, but without significant differences (all P>0.05). Conclusion: The mean global MBF and MBV at rest and under stress were (115.5±27.4) ml·100 g-1·min-1, (212.8±40.8) ml·100 g-1·min-1 and (17.6±4.0) ml/100 g, (25.8±4.6) ml/100 g. The MBF under stress perfusion and MBF absolute reserve of females are higher than those of males.

[Vigilance against a highly lethal insecticide chlorfenapyr poisoning (report of 4 cases and literature review)].

In order to improve the clinical attention to the poisoning of chlorfenapyr, the diagnosis and treatment strategy of chlorfenapyr poisoning were discussed. This paper collected 4 cases of chlorfenapyr in the emergency department of the Second Hospital of Hebei Medical University and 4 cases of literature review, summarized the clinical characteristics of pesticide poisoning cases containing chlorfenapyr in China, and summarized and analyzed the clinical data of the cases. Seven of the 8 patients died from poisoning by chlorfenapyr. Exposure to chlorfenapyr through respiratory tract and digestive tract showed high mortality. Fever, hyperhidrosis, elevated muscle enzymes and progressive central nerve damage were its prominent clinical characteristics. Most of the initial symptoms of exposure were not serious. Some patients, especially those with low exposure dose, had a relatively stable stage with or without clinical diagnosis and treatment. In case of sweating, obvious fever and disturbance of consciousness, the condition would deteriorate rapidly, respiratory and circulatory failure and eventually die. With the increase of production capacity and market launch, people have more opportunities to be exposed to chlorfenapyr. It is urgent to strengthen the basic and clinical research of chlorfenapyr poisoning; Attention should be paid to the observation and treatment in the initial stable stage of poisoning, which can be used as a reference for the treatment of oxidative phosphoric acid dissolving coupling agent (sodium pentachlorophenol) poisoning.

Contrast medium injection protocols for coronary CT angiography: should contrast medium volumes be tailored to body weight or body surface area?

AIM: To compare the uniformity and image quality between contrast media injection protocols adjusted for patient body weight (BW) versus body surface area (BSA) during coronary computed tomography (CT) angiography (CCTA). MATERIALS AND METHODS: Consecutive patients (n=489) with suspected coronary artery disease were randomised prospectively to one of two CCTA protocols. In the BW protocol (n=245), patients received individualised iodine delivery rates (≤50 kg: 1 g/s; 51-60 kg: 1.2 g/s; 61-70 kg: 1.4 g/s; 71-80 kg: 1.6 g/s; 81-90 kg: 1.8 g/s; 91-100 kg: 2 g/s; >100 kg: 2.2 g/s). In the BSA protocol (n=244), patients received 9,600 mg iodine/m2 of contrast medium over 12 seconds. Attenuation and image noise were measured. Signal-to-noise ratio and contrast-to-noise ratio were calculated. Image quality was scored. Attenuation was assessed for correlation with BW and BSA using linear regression. RESULTS: There were no statistically significant differences in mean arterial attenuation (396.8±47.6 versus 395.8±42.2 HU, p=0.804; 95% confidence interval: -7 to 9), image noise (25.2±5.8 versus 25.5±5.4 HU; p=0.549), signal-to-noise ratio (16.7±4.4 versus 16.6±3.6; p=0.902), contrast-to-noise ratio (25.1±5.8 versus 25.8±7.4; p=0.258) or image quality scores (4.1±0.9 versus 4±0.9; p=0.770) between the BW and BSA protocols. There was no correlation between BW and aortic attenuation or between BSA and aortic attenuation (p=0.324 and 0.932, respectively). CONCLUSION: The average contrast media attenuation and image quality was comparable between BW-adjusted protocol and BSA-adjusted protocol.

Direct comparison of the dynamics of IL-25- and 'allergen'-induced airways inflammation, remodelling and hypersensitivity in a murine asthma model.

BACKGROUND: Interleukin-25 has been implicated in the pathogenesis of asthma from studies on human asthmatics and in murine asthma models. OBJECTIVES: In this study, we hypothesized that chronic exposure of the airways to IL-25 alone is able to induce pathogenic changes observed in animal models of asthma. METHODS: We performed a detailed comparison of the dynamics of development of cellular infiltration, cytokine expression and airways remodelling and hyperresponsiveness in mice sensitized and challenged with OVA, a classical model of allergic asthma and those exposed to IL-25 alone. RESULTS: Intranasal challenge of BALB/c mice with IL-25 alone induced a delayed (compared with OVA-challenge), predominantly eosinophilic and lymphocytic infiltration into the airways lumen, along with increased production of Th2-type cytokines, chemokines and collagen, secretion of epithelial mucus, goblet cell hyperplasia, deposition of subepithelial collagen, airways smooth muscle cell hyperplasia and angiogenesis. Correspondingly, IL-25 as well as OVA challenge both induced airways hyperresponsiveness and increased lung tissue damping. In contrast, IL-25 exposure did not increase IgE or IgG1 production. CONCLUSIONS AND CLINICAL RELEVANCE: The data suggest that chronic airways exposure to IL-25 alone is sufficient to induce allergen- and IgE-independent, asthma-like airways inflammation, remodelling and hyperresponsiveness in mice. Thus, IL-25 is a key molecular target in asthma, irrespective of the coexistence of IgE-dependent mechanisms.

Interleukin-25 promotes basic fibroblast growth factor expression by human endothelial cells through interaction with IL-17RB, but not IL-17RA.

BACKGROUND: Unlike other IL-17 family members, the Th2-derived cytokine IL-25 (IL-17E) induces (promotes) Th2 responses. One or both of the two receptors for IL-25 (IL-17RA, IL-17RB) is expressed on inflammatory cells and tissue structural cells, suggesting that in addition to promoting Th2-type inflammation IL-25 may also act on structural cells at sites of Th2-type inflammation such as in the asthmatic bronchial mucosa to promote remodelling changes. OBJECTIVE: Our previous studies showed elevated expression of IL-25 and IL-17RB immunoreactivity in asthmatic airways with co-localization of the latter to endothelial cells. We therefore hypothesized that IL-25 acts on endothelial cells through this receptor to induce production of the key angiogenic and remodelling cytokine basic fibroblast growth factor (bFGF). METHODS: Polymerase chain reaction (PCR) immunocytochemistry/immunohistochemistry and ELISA were employed to detect expression of IL-17RB, IL-17RA and bFGF by human vascular endothelial cells (HUVEC) and immunoreactivity for IL-25 and bFGF in asthmatic bronchial biopsies. Receptor-blocking antibodies, PCR and an in vitro angiogenesis assay were used to investigate whether IL-25 acts on IL-17RB or IL-17RA to induce bFGF expression and angiogenesis. PCR was also employed to investigate the signalling pathways involved in IL-25-mediated bFGF expression. RESULTS: HUVEC constitutively expressed IL-17RB, IL-17RA and bFGF. Production of the latter was further increased by IL-25, but attenuated after blockade of the IL-17RB, but not the IL-17RA receptor. Neutralization of endogenous VEGF and bFGF completely abrogated IL-25-induced angiogenesis which was also inhibited by blocking IL-17RB, but not IL-17RA. The PI3K-specific inhibitor LY294002 also completely attenuated IL-25-induced bFGF expression. Immunoreactivity for IL-25 and bFGF was elevated in the asthmatic bronchial mucosa and the expression of each correlated with the other. CONCLUSIONS AND CLINICAL RELEVANCE: Our data support the hypothesis that IL-25 contributes to elevated bFGF in asthmatic airways by acting on the endothelial cell IL-17RB receptor through PI3K-signalling pathways. Targeting the pathways might benefit therapy of airways remodelling.

Molecular cloning of a new wheat calreticulin gene TaCRT1 and expression analysis in plant defense responses and abiotic stress resistance.

Calreticulin proteins play essential roles in regulating various metabolic processes and in molecular signal transduction in animals and plants. Using homologous PCR, we screened a cDNA library of the wheat resistance gene Yr5 from a near-isogenic line in the susceptible common wheat variety Taichung 29, which was inoculated with an incompatible race CYR32 of Puccinia striiformis. We isolated a novel full-length cDNA encoding calreticulin protein, which we named TaCRT1. Sequence analyses indicated that TaCRT1 contains an open reading frame of 1287 bp in length; it was deduced to encode 428 amino acids. Clustering analysis showed that TaCRT1 belongs to group III of the calreticulin protein family. Semi-quantitative RT-PCR was used to analyze expression profiles of the isolated gene under biotic and abiotic stresses. Expression of TaCRT1 was suppressed by exogenous application of phytohormones, such as abscisic acid and methyl jasmonate, and by dehydration; but it was induced by CYR32 infection and cold treatment. Based on the expression patterns, we propose that TaCRT1 participates in regulatory processes involved in defense responses and stress resistance in wheat.

Nonresonant quadrupolar second-harmonic generation in isotropic solids by use of two orthogonally polarized laser beams.

We demonstrate an experimental technique for isolating and enhancing quadrupolar second-harmonic generation in isotropic materials by using two orthogonally polarized laser beams that create wavelength-scale, forward-radiating gradients in the second-harmonic polarization.

The Arabidopsis ACT11 actin gene is strongly expressed in tissues of the emerging inflorescence, pollen, and developing ovules.

ACT11 represents a unique and ancient actin subclass in the complex Arabidopsis actin gene family. We have isolated and characterized the Arabidopsis ACT11 actin gene and examined its expression. Southern blotting with a 5' gene-specific probe showed that ACT11 was a single-copy gene in the genome. Northern analysis with a 3' gene-specific probe and reverse transcriptase-mediated PCR (RT-PCR) using gene-specific primers detected ACT11 mRNA at low levels in seedling, root, leaf, and silique tissue; at moderate levels in the inflorescence stem and flower; and at very high levels in pollen. The 5' region of the ACT11 gene, including the promoter region, the 5'-untranslated leader, the intron within the leader, and the first 19 actin codons, was fused to a beta-glucuronidase (GUS) reporter gene. The expression of the ACT11/GUS fusion was examined histochemically in numerous independent transgenic Arabidopsis plants. Strong ACT11/GUS activity was detected in rapidly elongating tissues and organs (e.g., etiolated hypocotyls, expanding leaves, stems) and in floral organ primordia. As the floral buds developed into mature flowers, strong GUS activity was gradually restricted to mature pollen and developing ovules. ACT11 appears to be the only Arabidopsis actin gene expressed at significant levels in ovule, embryo, and endosperm. The unique expression patterns in reproductive organs and the sequence divergence of the ACT11 actin gene suggest that the ACT11 isovariant plays distinct and required roles during Arabidopsis development.

The Arabidopsis thaliana ACT4/ACT12 actin gene subclass is strongly expressed throughout pollen development.

Plants contain complex actin gene families composed of several diverse and ancient subclasses of genes. One Arabidopsis actin gene subclass represented by the ACT4 and ACT12 genes has been isolated and characterized. Both actin genes have typical plant actin gene structures, including three small introns interrupting the coding region and an intron within the mRNA leader. Their encoded proteins differ from each other in only one amino acid, whereas they differ in 3-10% of their amino acids from the other five Arabidopsis actin subclasses. They also share a few small blocks of DNA sequence homology in the 5' flanking region near their TATA boxs, but not in their introns, 3' flanking regions, or degenerate positions within codons. Southern analysis with gene-specific probes from 5' flanking sequences showed that both were single copy genes in the genome. Both RNA gel blot analysis with 3' gene-specific probes and reverse transcriptase-mediated polymerase chain reactions (RT-PCR) with gene-specific primers detected low levels of ACT4 and ACT12 mRNAs in flowers and very high levels in pollen. The RT-PCR detected very low levels of these mRNAs in the vegetative organs. The 5' region from both genes, including the promoter region, TATA box, the sequence for the mRNA leader and its intron, and the first 19 actin codons, was fused to a beta-glucuronidase (GUS) reporter gene. Expression of the GUS fusions were examined histochemically in 40 independent transgenic Arabidopsis plants. Expression of the ACT4/GUS fusion was restricted to young vascular tissues, tapetum, and developing and mature pollen. Similar expression patterns in these tissues and cell types were observed for ACT12/GUS fusion, yet unlike ACT4, ACT12 was also strongly expressed in the root cap and in a ring of pericycle tissues during lateral root initiation and early development. The unique expression patterns of the ACT4/ACT12 actin gene subclass are discussed in light of recent data on the other expressed members of the Arabidopsis actin gene family.

Strong, constitutive expression of the Arabidopsis ACT2/ACT8 actin subclass in vegetative tissues.

Arabidopsis has a complex and ancient actin gene family encoding six divergent subclasses of proteins. One subclass is represented by ACT2 and ACT8, which encode nearly identical proteins. These two genes differ significantly in flanking and intron sequences and in silent nucleotide positions within codons. Gene-specific RNA gel blot hybridization and reverse transcriptase-mediated polymerase chain reaction (RT-PCR) assays showed that ACT2 and/or ACT8mRNAs were coordinately and strongly expressed in leaves, roots, stems, flowers, pollen, and siliques. Together they account for greater than 80% of the actin mRNA in most Arabidopsis organs. The 5' flanking regions, including the promoter, the mRNA leader exon, an intron in the mRNA leader, and the first 19 codons, were coupled to a beta-glucuronidase (GUS) reporter gene and transformed into Arabidopsis. The ACT2/GUS construct was expressed strongly in nearly all the vegetative tissues in seedlings, juvenile plants, and mature plants. These activities persisted in older tissues. Little or no expression was observed in seed coats, hypocotyls, gynoecia, or pollen sacs. In contrast, the expression of the ACT8/GUS construct was weaker. It was observed only in a subset of the organs and tissues expressing ACT2/GUS and was not significantly expressed in the flower. ACT2, ACT8, and ACT8/GUS mRNAs were present at moderate to high levels in pollen, and yet neither ACT2/GUS nor ACT8/GUS enzyme expression could be detected in pollen. This suggested a mechanism of translational control affecting ACT2 and ACT8 expression in some tissues. The conservation of protein sequence and overlapping patterns of expression, in spite of significant DNA sequence divergence, suggests that the function and regulation of these two genes have been conserved during the evolution of the Brassicaceae.

The arabidopsis ACT7 actin gene is expressed in rapidly developing tissues and responds to several external stimuli.

ACT7 encodes one of the six distinct and ancient subclasses of actin protein in the complex Arabidopsis actin gene family. We determined the sequence and structure of the Arabidopsis thaliana ACT7 actin gene and investigated its tissue-specific expression and regulation. The ACT7 mRNA levels varied by 128-fold among several different tissues and organs. The highest levels of aCT7 mRNA were found in rapidly expanding vegetative organs, the lowest in pollen. A translational fusion with the 5' end of ACT 7 (1.9 kb) joined to the beta-glucuronidase reporter gene was strongly and preferentially expressed in all young, developing vegetative tissues of transgenic Arabidopsis plants. ACT7 was the only Arabidopsis actin gene strongly expressed in the hypocotyl and seed coat. Although no beta-glucuronidase expression was seen in developing ovules or immature seeds, strong expression was seen in dry seeds and immediately after imbibition in the entire seedling. ACT7 was the only Arabidopsis actin gene to respond strongly to auxin, other hormone treatments, light regime, and wounding, and may be the primary actin gene responding to external stimuli. The ACT7 promoter sequence contains a remarkable number of motifs with sequence similarity to putative phytohormone response elements.

Structure and evolution of the actin gene family in Arabidopsis thaliana.

Higher plants contain families of actin-encoding genes that are divergent and differentially expressed. Progress in understanding the functions and evolution of plant actins has been hindered by the large size of the actin gene families. In this study, we characterized the structure and evolution of the actin gene family in Arabidopsis thaliana. DNA blot analyses with gene-specific probes suggested that all 10 of the Arabidopsis actin gene family members have been isolated and established that Arabidopsis has a much simpler actin gene family than other plants that have been examined. Phylogenetic analyses suggested that the Arabidopsis gene family contains at least two ancient classes of genes that diverged early in land plant evolution and may have separated vegetative from reproductive actins. Subsequent divergence produced a total of six distinct subclasses of actin, and five showed a distinct pattern of tissue specific expression. The concordance of expression patterns with the phylogenetic structure is discussed. These subclasses appear to be evolving independently, as no evidence of gene conversion was found. The Arabidopsis actin proteins have an unusually large number of nonconservative amino acid substitutions, which mapped to the surface of the actin molecule, and should effect protein-protein interactions.

Conserved expression of the Arabidopsis ACT1 and ACT 3 actin subclass in organ primordia and mature pollen.

We have proposed that ancient and divergent classes of plant actin genes have been preserved throughout vascular plant evolution, because they have distinct patterns of gene regulation. The hypothesis was explored for ACT1 and ACT3, which represent one of the six ancient subclasses in the Arabidopsis actin gene family. Comparison of ACT1 and ACT3 cDNA and genomic sequences revealed highly divergent flaking and intron sequences, whereas they encoded nearly identical proteins. Quantification of their level of divergence suggests that they have not shared a common ancestor for 30 to 60 million years. Gene-specific RNA gel blot hybridization and reverse transcriptase-polymerase chain reaction analyses demonstrated that the distribution of ACT1 and ACT3 mRNAs was very similar: both preferentially accumulated at high levels in mature pollen and at very low levels in the other major organs. The 5' flanking regions of both genes, including the promoter, leader exon and intron, and the first 19 condons, were fused to the beta-glucuronidase (GUS) reporter gene. The expression of these reporter fusions was examined in a large number of transgenic Arabidopsis plants. Histochemical assays demonstrated that both ACT1-GUS and ACT3-GUS constructs were expressed preferentially in pollen, pollen tubes, and in all organ primordia, including those in roots shoots, and the inflorescence. Comparison of the 5' flanking regions of ACT1 and ACT3 revealed a number of short conserved sequences, which may direct their common transcriptional and post-transcriptional regulation. The expression patterns observed were distinct from those of any other other Arabidopsis actin subclass. The conservation of their expression pattern and amino acid sequences suggests that this actin subclass plays a distinct and required role in the plant cytoskeleton.

Recombinant human bactericidal/permeability-increasing protein (rBPI23) is a universal lipopolysaccharide-binding ligand.

A recombinant 23-kDa protein (rBPI23) derived from human bactericidal/permeability-increasing protein (BPI) possesses potent endotoxin-neutralizing abilities in vitro and in vivo. Binding of rBPI23 to those endotoxins (lipopolysaccharides [LPSs]) encountered clinically would be a prerequisite for efficacy in decreasing mortality among patients suffering from gram-negative sepsis and shock, a disease state in which an etiological role for LPS has been implicated. rBPI23 binds well to lipid A (n = 7), to rough-mutant O-chain-deficient LPS (n = 18, Re to Ra chemotypes), to lipid A-core covalently linked to the O chain, to LPSs from clinically relevant serotypes (n = 100), and to bacterial cells (n = 88) of Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae, the species most often implicated in clinical gram-negative sepsis and shock. Significant binding of rBPI23 to these antigens took place at rBPI23 concentrations of 1 to 500 ng/ml (median, 16 to 32 ng/ml). Binding did not involve 3-deoxy-D-manno-octulosonate of the inner core. Determining the exact epitope recognized by rBPI23 would require further studies with synthetic lipid A substructures. The demonstrated ability of rBPI23 to universally bind LPS provides a sound basis for further testing of its endotoxin-neutralizing abilities, including clinical trials.

Lactoferrin is a lipid A-binding protein.

Lactoferrin (LF), a cationic 80-kDa protein present in polymorphonuclear leukocytes and in mucosal secretions, is known to have antibacterial effects on gram-negative bacteria, with a concomitant release of lipopolysaccharides (LPS, endotoxin). In addition, LF is known to decrease LPS-induced cytokine release by monocytes and LPS priming of polymorphonuclear leukocytes. Its mechanism of action is incompletely understood. We have now demonstrated by in vitro-binding studies that LF binds directly to isolated lipid A and intact LPS of clinically relevant serotypes of the species which most frequently cause bacteremia (Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa), as well as to lipid A and LPS of mucosal pathogens (among others, Neisseria meningitides and Haemophilus influenzae). Binding to LPS was inhibitable by lipid A and polymyxin B but not by KDO (3-deoxy-D-manno-octulosonate), a glycoside residue present in the inner core of LPS. Binding of LF to lipid A was saturable, and an affinity constant of 2 x 10(9) M-1 was calculated for the LF-lipid A interaction. Our data may explain, in part, the mechanism whereby LF exerts its antibacterial and anti-endotoxic effects. Further studies on the ability of LF to block the detrimental effects of LPS, both in vitro and in vivo, are warranted.

Frequencies of lipopolysaccharide core types in Escherichia coli strains from bacteraemic patients.

We have investigated the distribution of the various core types (R1, R2, R3, R4 and K-12) in 138 Escherichia coli isolates obtained from positive blood cultures. Rabbit antisera, raised against five rough strains expressing the respective core types, were made monospecific by extensive absorption. The reactivity of the antisera was tested in ELISA with bacterial cells that had been autoclaved for full exposure of core epitopes. One hundred and thirty strains could be typed directly, while eight strains required prior digestion with proteinase K for removal of cross-reactions. Ninety-four of the strains (68%) expressed the R1 type, and 9 (6.5%), 12 (8.7%), 7 (5.1%) and 3 (2.2%) strains expressed the R2, R3, R4 and K-12 core types, respectively. An R1R4 mixed core type, hitherto not yet described, was found in 13 (9.4%) strains. Results obtained with polyclonal antisera were in agreement with those obtained with monoclonal antibodies to the R1, R2 and R3 core types. Core typing may serve as an additional serological marker next to conventional typing of O-, H- and K-antigens.

[Application and examination of bioluminescent technique in the quality identification of BCG vaccines].

(1) The average viable rates of BCG Vaccines (Japan Strain/Danmark Strain) which were kept at 37c for 4 weeks were 69.4% and 57.8% respectively by BL method, while the average viable rates of the same BCG Vaccines were obtained to be 16.8% and 21.7% by CFU method. The coefficients of variation (CV) in the average viable rates of BCG vaccines were found to be 6.6% and 6.4% by BL method, while the CV were found to be 13.7% and 36.5% by CFU method. (2) The clinical immunization effects showed the positive transformation rates of skin test were 90.9% and 88.9% (P greater than 0.05) in the control group and test group by PPD check respectively. It indicated that there was no distinct difference. Because the test group was immunized with the BCG vaccine qualified only by BL method, clinical immunization effects were conformed with the detecting results of BL method.

Experimental research on utilization of bioluminescent technique to substitute the current viability count for BCG vaccine.

The possibility of using the bioluminescent (BL) technique to substitute the traditional viability count of colony forming units (CFU) of BCG vaccine was investigated. The results showed there is a significant dose-dependent correlation between the concentration of standard adenosine triphosphate (ATP) and ATP BL value. The ultrasonic-chloroform method designed by us yielded the best results. The correlation coefficient values (r) of BL of the liquid and lyophilized vaccine were found to be 0.8 155 and 0.8 484 respectively (P less than 0.05). The coefficient of variation (CV) between the BL value of different lots of ATP obtained was 3.2-4.4%, much lower than that of CFU (CV = 10.4-11.2%). The presence of bacterial clumps within the vaccine had great influence on the bacterial ATP value and on the CFU viability count. 2.8 fg of ATP was found in each CFU formed in the vaccine with clumps, while it was only 0.94 fg in the vaccine without clumps, indicating the superiority of the BL method. The BL method has shown a high sensitivity, good reproducibility and simplicity in handling with quick results and high accuracy. Therefore, we consider that the BL method can be used to substitute the CFU method.