[Analysis in diagnosis and treatment of 29 cases of cervical esophageal perforation]

Objective: To analyze and summarize the method and effect of cervical esophagus perforation. Methods: A total of 29 cervical esophageal perforation patients caused by foreign body were retrospectively analyzed from January 2012 to June 2018 in Department of Otorhinolaryngology Head and Neck Surgery, the First Affiliated Hospital of Nanchang University. Results: Among the 29 cervical esophageal perforation patients, 28 patients were extracted by lateral neck incision, 1 patient with carotid artery hemorrhea was rescued by repairing the fistula between carotid artery and esophage. All patients recovered and successfully discharged. There were no severe complications among all patients. Conclusions: The cervical CT scan is important for diagnosing a cervical esophageal perforation. Enhancement CT scan is necessay for a patient with haematemesis. Lateral neck incision would be first choice for patients with big foreign bodies. Inflammatory reaction and finger palpation are helpful for locating foreign bodies.

[Comparison between hybrid surgery and transabdominal preperitoneal surgery in treatment of irreducible inguinal hernia: A case-control study]

Objective: To compare the effects between hybrid surgery and transabdominal preperitoneal surgery in treatment of irreducible inguinal hernia. Methods: A total of 60 patients who underwent laparoscopic inguinal hernia repair between June 2011 and December 2017 were included in the study. Patients were divided into two group: hybrid surgery group (observation group, n=30) and transabdominal preperitoneal group (control group, n=30). The operation time, intraoperative bleeding, hospital stay, hospital cost and complications were analyzed. Results: The operative time of observation group and control group was 45 (35-65) minutes and 50(35-70) minutes, respectively. Intraoperative blood loss of two groups was 10(5-15) ml and 5(2-10) ml. The length of postoperative hospital stay was 2(1-4) days and 2(1-3) days in the two groups, respectively. And the hospitalization cost of two groups was 9 646 (9 066-11 560) yuan and 9 494(8 989-10 660) yuan, respectively. The intraoperative complications occurred in 4 cases in control group, including 1 case of vas deferens injury, 2 cases of spermatic vessel injury and 1 case of inferior epigastric artery injury. No intraoperative complications occurred in observation group. Perioperative complications in observation group and control group included dysuria (6.7% vs 10.0%), scrotum hematoma (3.4% vs 0%), wound pain (46.7% vs 6.7%) and fever (16.7% vs 20.0%). Twelve months of follow-up was completed in all the patients, and no recurrence or infections occurred in the two groups. The incidence of seroma in observation group and control group was 26.7%, 33.3%, respectively. One case of foreign body sensation and one case of chronic pain occurred in control group. The incidence of perioperative wound pain in patients undergoing hybrid surgery was higher than those undergoing transabdominal preperitoneal surgery (P<0.05), but no statistical differences were observed for other variables between the two groups (all P>0.05). Conclusion: Hybrid surgery is safe and feasible for the treatment of irreducible inguinal hernia. Though with a higher incidence of postoperative acute pain, it may have advantages of avoiding injuries of the vas deferens and spermatic vessels.

The change of volatile compounds of two kinds of vinasse-cured ducks during processing

Vinasse-cured duck was processed by boiling, salting, and vinasse-dry-curing or vinasse-wet-curing. Volatile compounds, moisture contents, reducing sugars, and thiobarbituric acid reactive substances (TBARS) values during processing were determined. Reducing sugars decreased during boiling and increased after vinasse-curing. TBARS values increased throughout the processing. The volatiles of ducks during processing and vinasse-curing agents (dry vinasse and vinasse sauce) were 125 compounds. The first principal component (PC1) belonged to the flavor of cooked duck, whereas the second principal component (PC2) represented the flavor of yellow rice wine. The 66.49 and 29.61% of typical aroma of vinasse-dry-cured product were from dry vinasse and lipid oxidation, respectively, whereas the 75.58 and 21.89% of aroma of vinasse-wet-cured product were from vinasse sauce and lipid oxidation, respectively. Lipid oxidation products increased after boiling, whereas salting promoted their release. Compared with vinasse-wet-cured duck, vinasse-dry-cured product presented richer aroma of lipid oxidation and weaker flavor of vinasse-curing agents. Besides, protein denaturation which was caused by ethanol could influence the retention and release of flavor. In conclusion, two kinds of vinasse-curing methods influenced the characteristic volatiles of products and their generation during processing.

[The Wuhan Twin Birth Cohort Study]

The prevalence of child and adolescent growth and mental-behavior related diseases are increasing, and the pathogenesis are complex. Twins are excellent natural resources for complex chronic diseases research as they share the maternal intrauterine environment, born at the same time and share the same family environment in early years, which could benefit the adjust ment of confounding factors, such as age, genetic factors and early family environmental factors. Birth cohort with twin families involved could be more effective in exploring the genetic and environmental factors for complex chronic diseases at the very beginning of life. This paper summarizes the objective, content, progress, strengths and potential problems of Wuhan Twin Birth Cohort, with emphasis on the overall design and progress of the study.

[Discussion of laparoscopic transabdominal preperitoneal repair for recurrent inguinal hernia]

OBJECTIVE

To explore the surgical techniques and the clinical efficacy of laparoscopic transabdominal preperitoneal repair (TAPP) for recurrent inguinal hernia.

METHODS

Clinical data of 367 patients with recurrent inguinal hernia who underwent TAPP repair from Mar. 2009 to Mar. 2015 in Beijing Chao-Yang Hospital of Capital Medical University were analyzed retrospectively.

RESULTS

Laparoscopic operations were completed successfully in 365 cases, however, 2 cases were converted to open surgery.The operation time was (55.7±19.3) min (30-100 min) and the hospital stay was (4.9±2.7) d (2-12 d). The incidences of postoperative pain, hydrocele, and urinary retention were 4.1%(15/367), 13.1%(48/367), and 1.3%(5/367) respectively.Other complications such as foreign body sensation, wound infection, and intestinal obstruction.All cases were followed up from 3 to 72 months ((36.5±14.7) months), 2 recurrent cases was observed and no mesh infection and long-term chronic pain were observed.

CONCLUSIONS

Laparoscopic TAPP repair has advantages of minimal invasion and few complications, which is safe and effective for recurrent inguinal hernia.

Real-space imaging of Kondo screening in a two-dimensional O₂ lattice

Kondo lattice systems can exhibit unusual many-body behaviors that result from the interplay between onsite Kondo screening and intersite coupling. We used scanning tunneling microscopy to image the Kondo resonance in a nonconventional Kondo lattice formed by self-assembled oxygen (O(2)) molecules, which are paramagnetic, on the gold reconstructed surface [Au(110)-1×2]. The interplay between the intermolecular coupling for molecules adsorbed along chains and the onsite Kondo effect leads to the coexistence of both local and nonlocal Kondo screening at the atomic level. The latter provides evidence for collective deconfinement of magnetization induced in Au, whereas the former shows local "hybridization" between the Kondo clouds of nearest-neighbor O(2) molecules.

Electric and magnetic excitation of coherent magnetic plasmon waves in a one-dimensional meta-chain

A one-dimensional diatomic meta-chain with equal-size holes and different-length slits is designed. Broadband coherent magnetic plasmon waves (MPW) are formed in such a system, excited by both the electric resonance in the slits and the magnetic resonance in the holes in a wide range of incidence angles (0°-40°) and broad frequency bands (200-230 THz). The dispersion properties of the MPW measured in our experiments agree with the theoretical calculation based on the Lagrange model. The coherent MPWs reported in this paper may have applications in subwavelength integrated nanocircuits.

Coaxial nanocables of codoped double-walled carbon nanotubes

The electronic and optical properties of codoped double-walled carbon nanotubes (DWNTs), in which nucleophilic atoms (potassium) are adsorbed outside the outer tube and electrophilic molecules (NO(2)) are adsorbed inside the inner tube, are investigated by density functional theory. It is found that the inner core tube is p-type doped and the outer shell tube is n-type doped, forming a radial p-n junction of DWNTs. A type-II band energy alignment is formed at the interface of two constituting walls of codoped DWNTs. Moreover, optical calculations show that the band edge absorption is zero for pristine DWNTs, while it is pronounced for the codoped DWNTs. This absorption of codoped DWNTs leads to charge separation in the interface of two walls of DWNTs with holes located on core tube while electrons located on shell one. The properties of DWNT coaxial nanocables demonstrated here can find future applications in electronic and optoelectronic devices.

Structural-configurated magnetic plasmon bands in connected ring chains

Magnetic resonance coupling between connected split ring resonators (SRRs) and magnetic plasmon (MP) excitations in the connected SRR chains were theoretically studied. By changing the connection configuration, two different coupling behaviors were observed, and therefore two kinds of MP bands were formed in the connected ring chains accordingly. From the extracted dispersion properties of MPs, forward and backward characteristics of the guided waves are well exhibited corresponding to the homo- and hetero-connected chains. Notably, thanks to the conductive coupling the revealed MP waves both have wide bandwidth even starting from the zero frequency. These results are suggested to provide instructions to build new kinds of subwavelength waveguides.

Sharp corners in the cross section of ultrathin Si nanowires

We have determined stable geometries for pristine Si nanowires grown along their 100 axis through systematic density functional studies. Strikingly, Si nanowires with diameters smaller than 1.7 nm prefer a shape that has a square cross section. This stems from dimerization between corner atoms and also from benign reconstruction patterns that maximally saturate Si dangling bonds.

Characterization of the myxoma virus M118L protein: a novel essential poxvirus IMV-associated protein

Myxoma M118L ORF has the capacity to encode a 76 amino acid protein that is highly conserved in other vertebrate poxviruses including vaccinia (A30L), molluscum contagiosum (MC136L), yaba tumour virus (D13L) and fowlpox virus (FPV 194). The time course analysis by Western blotting using M118L antibody showed that the M118L ORF is expressed as a typical poxvirus late gene. The M118L protein can be detected in both the virus infected cytosolic and membrane fractions, even though the M118L protein does not possess a predicted transmembrane domain. The protein was found to be associated with the sucrose gradient purified myxoma intracellular mature virus (IMV) as determined by Western blotting with M118L antibody. Furthermore, the M118L protein associated with the IMV can be surface labeled with water-soluble biotin and is released from the purified IMV with treatment of nonionic detergent NP-40, indicating that the M118L protein is associated with the outer membrane of myxoma IMV. Unexpectedly, an IMV-associated M118L protein isoform was observed to bind tightly to Streptavidin beads, unlike the six other detectable myxoma IMV surface proteins, suggesting an unusual post-translational modification, such as biotinylation. Extensive attempts to generate the M118L deletion mutant using standard homologous recombination technique with E. coli gpt gene as a positive selection marker were unsuccessful. Although PCR analysis clearly indicated the presence of the correctly targeted M118L deletion mutants in mixed recombinant virus plaques selected with mycophenolic acid (MPA), repeated passages and plaquing failed to segregate the pure M118L deletion mutant from either single crossover recombinants or regenerated wild type parental viruses. Taken together, our data strongly indicate that the M118L is a novel poxvirus IMV associated protein that is essential for virus viability.

[Genetic diversity of Fagoyrum tataricum cultivated in north Liangshan Prefecture of Yi Nationality, Sichuan, China]

In the present paper is stated the accomplishment of the studies of 17 populations of cultivated Fagopyrum tataricum (L.) Gaertn. from the counties of Yuexi and Ganluo in North Liangshan Autonomous Prefecture of Yi Nationality, Sichuan Province, China by means of starch gel electrophoresis and cluster analysis of agrobiology features. Seven enzymes, and 15 loci were assessed. The result shows that the genetic diversity of F. tataricum within population is higher than in the South Prefecture and in species F. esculentum from other areas. The A, P, Ho and He are 1.9, 52.1%, 0.190 and 0.262 respectively. The FST is 0.199 which is close to the average level of wild plants. A conservation strategy of the genetic resource of F. tataricum is suggested. Two populations of local variety "Youchiqiao" have the richest genetic diversity, P = 60.0%, Ho = 0.260 and 0.301 and they should be protected particularly. Two populations of local variety "Xiaomiqiao" with higher genetic diversity, as well as three populations of local varieties of "Qiukuqiao", "Equkuqiao" and "Geluokuqiao" with special genetic position should be protected too.

[Genetic diversity and differentiation of cultivated Fagoyrum tataricum populations from three counties in south Liangshan Automomous Prefecture of Yi Nationality, Sichuan, China]

Genetic diversity and differentiation among 8 cultivated populations of Fagopyrum tataricum from the counties of Jinyang, Leibo and Miyi in south Liangshan Autonomous Prefecture of Yi Nationality, Sichuan Province, China were investigated using allozyme electrophoresis. The allozymic diversity is roughly correlated with agrobiological features. The results suggest that genetic diversity of F. tataricum is quite high. The mean number of alleles per locus A is 1.8; the percentage of polymorphic loci P is 46.6%, and the mean observed heterozygosities Ho and the mean expected heterozygosities He are 0.187 and 0.218 respectively, the ratios of gene diversities of heterozygosities Fsr is 0.22, which indicates that there is 22 percent of genetic differentiation among populations, and suggests that for protecting genetic resources all the populations should be included in.

The ORF RTL1 transcript of fowl adenovirus type-8 is spliced and truncated at late stages of the virus replication cycle

Two transcription products were found for the open reading frame (ORF) RTL1 located near the right terminus of the fowl adenovirus type-8 genome. The larger transcript, which was transcribed mostly during the early stage of the virus infection, contains the complete sequence (933 nucleotides) of the predicted ORF from the genomic DNA sequence encoding a 311 amino acid (aa) polypeptide. In contrast, the shorter transcript, which was more predominant at the late stage of the infection, was missing 580 nucleotides (from nucleotide 117 to 696). A premature stop codon was introduced at 210 nucleotides downstream from the start codon and the shorter transcript would encode a 70 aa polypeptide. This observation indicates that the ORF RTL1 may produce two different proteins, which function differently at different stages of the virus infection. Another possibility is that the virus may use alternative splicing as a mechanism to control the expression of the ORF, since the spliced transcript was prematurely terminated at the late stage of the infection.

Immunomodulatory proteins of myxoma virus

Poxviruses collectively encode an impressive collection of diverse immunomodulatory proteins. In this review we draw attention to some of the new open reading frames (ORFs) discovered during the sequencing of the myxoma virus DNA genome [Cameron C, Hota-Mitchell S, Chen L, Barrett J, Cao J-X, Macaulay C, Willer D, Evans D, McFadden G (1999) The complete DNA sequence of myxoma virus. Virology 264:298-318] that may function to subvert the host immune system. Most of these predicted functions are speculative but some of the deduced primary amino acid sequences contain intriguing similarities to known cellular and viral proteins in the public domain for which immunomodulatory functions have been assigned.

The complete DNA sequence of myxoma virus

Myxomatosis in European rabbits is a severely debilitating disease characterized by profound systemic cellular immunosuppression and a high rate of mortality. The causative agent, myxoma virus, is a member of the poxvirus family and prototype of the Leporipoxvirus genus. As a major step toward defining the genetic strategies by which the virus circumvents host antiviral responses, the genomic DNA sequence of myxoma virus, strain Lausanne, was determined. A total of 171 open reading frames were assigned to cover the 161.8-kb genome, including two copies each of the 12 genes that map within the 11.5-kb terminal inverted repeats. Database searches revealed a central core of approximately 120 kb that encodes more than 100 genes that exhibit close relationships to the conserved genes of members of other poxvirus genera. Open reading frames with predicted signal sequences, localization motifs, or homology to known proteins with immunomodulatory or host-range functions were examined more extensively for predicted features such as hydrophobic regions, nucleic acid binding domains, ankyrin repeats, serpin signatures, lectin domains. and structural cysteine spacings. As a result, several novel, potentially immunomodulatory proteins have been identified, including a family with multiple ankyrin-repeat domains, an OX-2 like member of the neural cell adhesion molecule family, a third myxoma serpin, a putative chemokine receptor fragment, two natural killer receptor-like species, and a variety of species with domains closely related to diverse host immune regulatory proteins. Coupled with the genomic sequencing of the related leporipoxvirus Shope fibroma virus, this work affirms the existence of a conserved complement of poxvirus-specific core genes and expands the growing repertoire of virus genes that confer the unique capacity of each poxvirus family member to counter the immune responses of the infected host.

Immunomodulation by viruses: the myxoma virus story

Myxoma virus is a poxvirus pathogen of rabbits that has evolved to replicate successfully in the presence of an active immune response by an infected host. To accomplish this, the virus has developed a variety of strategies to avoid detection by or obstruct specific aspects of the antiviral response whose consolidated action is antagonistic to virus survival. We describe two distinct viral strategies carried out by viral proteins with which myxoma virus subverts the host immune response. The first strategy is the production of virus-encoded proteins known as viroceptors or virokines that mimic host receptors or cytokines. These seek to actively block extracellular immune signals required for effective virus clearance and produce a local environment in the infected tissue that is "virus friendly". The second strategy, carried out by intracellular viral proteins, seeks to retard the innate antiviral responses such as apoptosis, and hinder attempts by the infected cell to communicate with the cellular arm of the immune system. By studying these viral strategies of immune evasion, the myxoma system can provide insights into virus-host interactions and also provide new insights into the complex immune system.

Subversion of cytokine networks by viruses

Viruses and the immune system have been competitors throughout their co-evolution. It is therefore not surprising that the viruses in circulation today possess a variety of strategies to counteract those aspects of the immune system that are involved in virus clearance. Examination of these virus encoded functions provides an important view of immune function and an appreciation of the complexity of the virus-host interaction. It is clear that viruses, seeking to subvert the immune system, have become adept in blocking the communication channels of the immune system. There are numerous examples of viral proteins that target the cytokine networks, disrupting the processes by which the delicately balanced immune system is regulated. This review focuses on the gene products of poxviruses, adenoviruses and herpesviruses that function primarily as immune-modulators.

Sequence and transcriptional analysis of terminal regions of the fowl adenovirus type 8 genome

Fowl adenovirus (FAdV) type 1, CELO strain has no homologies to mastadenovirus E1A, E1B, E3 and E4, which regulate virus gene expression, DNA replication and virus-host interaction. Similarly, the right 5 kb and left 15 kb ends of CELO virus DNA are non-homologous to mastadenoviruses. To compare CELO virus with another FAdV, 7.5 kb of the left and 17 kb of the right ends of FAdV type 8 (strain A-2A) were sequenced and nine and 17 open reading frames (ORFs), respectively, were found. This FAdV-8 genome was similar to CELO virus in that (1) the central region contained the major structural protein genes including the fibre, pVIII, 100K, late 33K and pIVa2 genes, which were in the same order as in mastadenoviruses, (2) no homologues of mastadenovirus E1A, E1B, E3 and E4 were found in the ends, and (3) the left 6 kb and the right 13 kb ends showed no homology to mastadenoviruses. Several genomic features were unique to FAdV-8 compared to CELO virus. FAdV-8 contained one fibre gene in contrast to two in CELO virus. Three of eight unassigned ORFs in the left and five of 13 unassigned ORFs in the right ends were unique compared to CELO virus. Two sets of tandem repeats, one with five identical 33 bp repeats and the other with more than ten identical 135 bp repeats, mapped between 4.5 and 7.5 kb from the right terminus. No virus-associated RNA gene was found. Fifteen of 16 unique FAdV-8 ORFs tested were, as determined by RT-PCR, transcribed early.

A human homolog of the vaccinia virus HindIII K4L gene is a member of the phospholipase D superfamily

We have identified a human gene encoding a protein with 48% amino acid identity to the vaccinia virus (VV) K4L gene product. Both contain motifs characteristic of the phospholipase D (PLD) protein superfamily. These proteins are also related to vaccinia virus p37, encoded by the F13L gene, which is required for envelopment and spread of the virus. The similarity to phospholipase D provides insight into the mechanisms and evolution of these processes.

A new family of lipolytic plant enzymes with members in rice, arabidopsis and maize

We have noted a striking similarity between the sequences of proteins in a novel family of lipases we recently reported [Upton, C. and Buckley, J. T. (1995) Trends Biol. Sci. 20, 178-9] and more than 120 sequences from the database of Expressed Sequence Tags (dbEST) which correspond to at least 30 unique genes from arabidopsis, rice and maize. A cDNA (Arab-1) corresponding to one of these sequences was isolated, sequenced and translated. There was significant similarity to sequences in the new lipase family over the entire open reading frame of Arab-1 and when expressed in E. coli, the gene product was lipolytic. Arab-1 and genes for some of the other plant proteins appear to be differentially expressed. They may play a role in the regulation of lipid metabolism during plant development.

Passage of Japanese encephalitis virus in HeLa cells results in attenuation of virulence in mice

Of four wild-type strains (Nakayama-original, SA14, 826309 and Beijing-1) of Japanese encephalitis (JE) virus that were passaged six times in HeLa cells (HeLa p6), two (Nakayama-original and 826309) became attenuated for mice. In the case of strain Nakayama-original, the virulence for mice was markedly reduced and attenuation was retained on passage in primary chicken embryo fibroblast, LLC-MK2 and C6/36 cells. The binding of non-HeLa-passaged Nakayama virus to mouse brain membrane receptor preparations could be differentiated from binding by Nakayama HeLa p6 virus, suggesting that the envelope (E) protein is involved in the attenuated phenotype. Both of the attenuated viruses can be distinguished from the virulent non-HeLa-passaged parental viruses by examination with E protein reactive vaccine and wild-type-specific monoclonal antibodies (MAbs). The vaccine-specific MAb V23, which is only reactive with the SA14 series of live vaccine viruses, recognized the HeLa cell-attenuated Nakayama-original and 826309 viruses, whereas two wild-type-specific MAbs (MAbs K13 and K39) lost reactivity. Comparison of the nucleotide sequences of the structural protein genes of the 826309 and Nakayama-original virulent parent and attenuated HeLa p6 viruses revealed that the viruses differed by 37 and 46 nucleotides coding for eight and nine amino acid mutations, respectively. However, other than one amino acid in the E protein, the membrane and E protein amino acid sequences of the two attenuated HeLa p6 viruses were identical.

Sequence analysis of HindIII Q2 fragment of capripoxvirus reveals a putative gene encoding a G-protein-coupled chemokine receptor homologue

The DNA sequence of the HindIII Q2 fragment near the left terminus of the capripoxvirus (KS-1 strain) genome was determined. The sequence contains two complete open reading frames (ORFs) and a part of a third. Analysis of the deduced amino acid sequence of one of these ORFs, Q2/3L, revealed that this gene has the capacity to encode a protein which is related to members of the G-protein coupled chemokine receptor subfamily, the swinepoxvirus K2R and the human cytomegalovirus US28 ORFs. It has the key structural characteristics of the G-protein-coupled receptor superfamily, e.g., seven hydrophobic regions, predicted to span the cell membrane, and the cysteine residues in the first and second extracellular loops that are implicated in formation of a disulfide bond. Southern blot analysis showed that all three species of the Capripoxvirus genus, i.e., sheep pox, goat pox, and lumpy skin disease of cattle, contain copies of this putative G-protein-coupled chemokine receptor homologue.

Immunogenicity of experimental live attenuated Japanese encephalitis vaccine viruses and comparison with wild-type strains using monoclonal and polyclonal antibodies

A total of 105 hybridomas secreting anti-Japanese encephalitis (JE) virus monoclonal antibodies (mAbs) were generated from six fusions against four strains of JE virus: wild-type strains SA14 and G8924 and live attenuated vaccines SA14-5-3 and SA14-14-2 (PDK-9). Most of the mAbs (87%) elicited haemagglutination inhibition activity while only a minority (24%) elicited neutralization. None of the mAbs prepared against SA14-5-3, parent of SA14-14-2, elicited neutralization while the only mAbs prepared against SA14-14-2 that elicited neutralization recognized flavivirus cross-reactive epitopes. In comparison, mAbs raised against wild-type strains showed that a spectrum of epitopes with different specificities, including JE type-specific epitopes, elicited neutralizing activity. Two mAbs, prepared against SA14-5-3 virus, were found to be vaccine-specific and five, prepared against strains SA14 and G8924, were wild-type-specific.

Antigenic characterization of the live attenuated Japanese encephalitis vaccine virus SA14-14-2: a comparison with isolates of the virus covering a wide geographic area

In China, a live attenuated Japanese encephalitis (JE) vaccine, based on strain SA14-14-2, has been derived from the wild-type strain SA14 as an alternative to the current inactivated vaccines such as Nakayama-NIH and P-3. SA14-14-2 has been characterized using monoclonal antibodies derived in mice, using HAI and neutralization tests, and compared with other Chinese live vaccine clones and 14 wild-type strains of JE virus. Wild-type strain SA14 was found to be a poor immunogen and antigenically distant from all other viruses examined. The vaccine derivatives SA14-5-3 was more immunogenic than its wild-type parent, while SA14-14-2 (derived from SA14-5-3) was more immunogenic than SA14-5-3 and elicited a cross neutralizing antibody response. Our studies indicated that JE virus strain Nakayama elicited as good a neutralizing antibody response in hyperimmunized mice as the SA14-14-2 vaccine clones grown in either primary hamster kidney (PHK) or primary dog kidney (PDK) cells. A single dose of live SA14-14-2 (PHK) also elicited a good antibody response. Antigenic variation between wild-type and vaccine clones of JE virus were detected but were not considered significant in terms of controlling JE virus infections by vaccination.