[Efficacy and safety of endovascular therapy after 24 h from ischemic stroke onset in patients with acute anterior circulation ischemic stroke]

Objective: To explore the effectiveness and safety of endovascular treatment (EVT) for patients with acute anterior circulation ischemic stroke with symptom onset exceeding 24 h. Methods: In this retrospective cohort study, data were extracted from patients who underwent endovascular treatment for acute anterior circulation ischemic stroke at the First Hospital of Jilin University from February 2019 to April 2022. A total of 569 patients were included, with a mean age of 63 (54-70) years. Among them, 398 (69.9%) were male. The patients were divided into two groups based on symptom onset time:>24 h group and≤24 h group. Propensity score matching (PSM) was used to match the patients in a 1︰1 ratio between the>24 h group and the≤24 h group. Logistic regression was used to evaluate the impact of symptom onset time on outcome events. Results: Before PSM, compared with≤24 h group, the>24 h group had a younger age [56 (48, 64) vs. 64 (55, 70), Z=-3. 60, P<0.001]; lower proportion of prior atrial fibrillation [1.8% (1/57) vs. 21.1% (108/512), χ2=12.39, P<0.001]; lower proportion of wake-up stroke [7.0% (4/57) vs. 27.7% (142/512), χ2=11.54, P<0.001]; lower baseline NIHSS score [11.0 (7.5, 14.0) vs. 13.0 (10.0, 16.0), Z=-3.22, P<0.001]; and a higher American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology(ASITN/SIR) grading (P<0.001). After PSM, there were no significant differences in baseline characteristics between the two groups. There was no significant difference in the proportion of patients with a modified Rankin Scale (mRS) score≤2 at 90 days after surgery between the two groups (before matching: 42.0% vs. 40.4%, OR=0.745, 95%CI 0.407-1.362, P=0.339; after matching: 51.8% vs. 39.3%, OR=0.511, 95%CI 0.212-1.236, P=0.136). No significant differences were observed in the incidence of any safety outcomes between the>24 h group and the≤24 h group. Conclusion: For patients with acute anterior circulation ischemic stroke with symptom onset exceeding 24 h, EVT is feasible after strict radiological screening and has similar safety and effectiveness as for patients with symptom onset under 24 h.

[Effect of exosome derived from ovarian cancer cell on the differentiation of fibroblast]

Objective: To study the effects of exosome secreted by ovarian cancer (OC) cell on the differentiation and metastasis of normal fibroblasts (NFs). Methods: NFs were collected from patients who underwent hysteromyoma resection in the Affiliated Hospital of Qingdao University from May to December 2019. Exosome was extracted from the culture supernatant of SKOV3 cells by using ultra-high-speed centrifugation. The NFs were co-cultured with condition medium (CM), exosome of SKOV3 (SKOV3-exo) and control medium. The expression levels of fibroblast activation protein (FAP) and α-smooth muscle actin (α-SMA) were detected by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blot. The metastatic ability of NFs was detected by Transwell array. Results: Under the transmission electron microscope, the extracellular vesicles extracted from the culture supernatant of SKOV3 were 30-100 nm in diameter with cup holder-like bilayer membrane structure, and the protein expression levels of TSG101 and HSP27 in exosomes (1.00±0.05 and 1.12±0.13) were higher than those of ovarian cancer SKOV3 cells (0.22±0.21 and 0.36±0.14, respectively, P<0.05). PKH67 fluorescently labeled exosomes could be taken up by NFs. The expression levels of α-SMA and FAP mRNA in CM group(2.91±0.15 and 3.21±0.33)and SKOV3-exo group (3.50±0.21 and 4.63±0.24, respectively) were higher than that in blank group (1.00±0.06 and 1.00±0.13, P<0.05). The protein expression levels of α-SMA and FAP in CM group and SKOV3-exo group (0.89±0.11 and 1.25±0.09, 0.81±0.09 and 1.20±0.12) were higher than those in the blank group (0.12±0.31 and 0.11±0.19, respectively, P<0.05). The migrated numbers of cells in the CM group and SKOV3-exo group [(215.01±14.80) and (389.72±19.43), respectively] were higher than that in the blank group [(113.73±4.70), P<0.05]. Conclusion: The exosome secreted by SKOV3 cells can be taken up by NFs, which makes it to differentiate into cancer associated fibroblasts (CAFs) and significantly enhances its metastatic ability, indicating that OC cells may promote the transformation of normal ovarian mesenchymal fibroblasts to CAFs through exosome pathways, and then promote the development of ovarian cancer.

Neurodevelopmental Outcomes after Congenital Heart Disease Surgery in Infancy: A 2-Year Serial Follow-Up

BACKGROUND

The aim of this study is to assess the neurodevelopmental status of infant patients who underwent cardiac surgery in infancy and to investigate the factors affecting the neurodevelopmental status.

METHODS

This retrospective study included 108 patients who underwent cardiac surgery before the age of one. We used the Bayley Scales of Infant Development II to evaluate the neurodevelopmental status. All patients were analyzed according to the presence of the syndrome. Patients without the syndrome were analyzed according to the presence of brain lesions.

RESULTS

The mean mental developmental index (MDI) and the mean psychomotor developmental index (PDI) were 76.11 ± 20.17 and 65.95 ± 18.34, respectively, in the first evaluation, and 73.98 ± 22.53 and 69.48 ± 20.86, respectively, in the second evaluation. In the subgroup analysis, no significant difference was observed between the first evaluation and the second evaluation.

CONCLUSIONS

No significant difference was observed in the degree of development of the patients in the two evaluation periods. Although the presence of syndrome, brain lesion, or gestational age affected the degree of developmental delay, more than half of the patients had developmental delay in the two evaluation periods in any of the subgroup. Therefore, the necessity of early screening and early rehabilitation intervention is emphasized.

The effect of robot-assisted gait training on cortical activation in stroke patients: A functional near-infrared spectroscopy study

OBJECTIVE

To investigate the effects of the robot-assisted gait training on cortical activation and functional outcomes in stroke patients.

METHODS

The patients were randomly assigned: training with Morning Walk® (Morning Walk group; n = 30); conventional physiotherapy (control group; n = 30). Rehabilitation was performed five times a week for 3 weeks. The primary outcome was the cortical activation in the Morning Walk group. The secondary outcomes included gait speed, 10-Meter Walk Test (10MWT), FAC, Motricity Index-Lower (MI-Lower), Modified Barthel Index (MBI), Rivermead Mobility Index (RMI), and Berg Balance Scale (BBS).

RESULTS

Thirty-six subjects were analyzed, 18 in the Morning Walk group and 18 in the control group. The cortical activation was lower in affected hemisphere than unaffected hemisphere at the beginning of robot rehabilitation. After training, the affected hemisphere achieved a higher increase in cortical activation than the unaffected hemisphere. Consequently, the cortical activation in affected hemisphere was significantly higher than that in unaffected hemisphere (P = 0.036). FAC, MBI, BBS, and RMI scores significantly improved in both groups. The Morning Walk group had significantly greater improvements than the control group in 10MWT (P = 0.017), gait speed (P = 0.043), BBS (P = 0.010), and MI-Lower (P = 0.047) scores.

CONCLUSION

Robot-assisted gait training not only improved functional outcomes but also increased cortical activation in stroke patients.

Who Will Continuously Depend on Compression to Control Persistent or Progressive Breast Cancer-Related Lymphedema Despite 2 Years of Conservative Care?

BACKGROUND

When a patient with breast cancer-related lymphedema (BCRL) depends on continuous compression management, that is, when interstitial fluid accumulation is continuously ongoing, surgical treatment should be considered. Physiologic surgery is considered more effective for early-stage lymphedema. The purpose of this study was to identify predictors of patients with BCRL who will be compression-dependent despite 2 years of conservative care.

METHODS

This study included patients with BCRL who followed up for 2 years. Patients were classified into two groups (compression-dependent vs. compression-free). We identified the proportion of compression-dependent patients and predictors of compression dependence.

RESULTS

Among 208 patients, 125 (60.1%) were classified into the compression-dependent group. Compression dependence was higher in patients with direct radiotherapy to the lymph nodes (LNs), those with five or more LNs resections, and those with BCRL occurring at least 1 year after surgery.

CONCLUSIONS

BCRL patients with direct radiotherapy to the LNs, extensive LN dissection, and delayed onset may be compression-dependent despite 2 years of conservative care. Initially moderate to severe BCRL and a history of cellulitis also seem to be strongly associated with compression dependence. Our results allow for the early prediction of compression-dependent patients who should be considered for physiologic surgery.

Anti-adhesive effect of a thermosensitive poloxamer applied after the removal of nasal packing in endoscopic sinus surgery: a randomised multicentre clinical trial

OBJECTIVE

To compare the efficacies of a thermosensitive poloxamer (TPX) and Merogel in preventing adhesion applied after the removal of nasal packing in endoscopic sinus surgery as a non-inferiority trial.

DESIGN

Randomised, multicentre, single-blind, active-controlled, matched-pair study.

SETTING

Yonsei University Gangnam Severance Hospital, Korea University Guro Hospital.

PARTICIPANTS

A total of 70 patients were enroled and underwent endoscopic sinus surgeries. Four of the patients did not complete their follow-up. Analysis of the 66 enroled patients having completed postoperative assessment was performed. The severity of rhinosinusitis was graded with a Lund-McKay CT score, and only those with bilateral disease and a CT score difference ≤2 between sinuses were included.

MAIN OUTCOME MEASURES

An independent rhinologist from a third institution through a blinded assessment with digital photoendoscopy of the middle meati bilaterally taken postoperatively.

RESULTS

In the blinded assessment, thermosensitive poloxamer (anti-adhesion rate: 92%) was similar to Merogel (anti-adhesion rate: 89%). Evaluation of the presence and grade of adhesion, oedema, and infection in the middle meatus revealed no significant differences between the thermosensitive poloxamer group and the Merogel group at all postoperative periods.

CONCLUSION

Anti-adhesive effects of thermosensitive poloxamer are similar to those of Merogel. Therefore, thermosensitive poloxamer can be considered a safe alternative to Merogel for preventing adhesion in patients undergoing endoscopic sinus surgeries, and further evaluation of thermosensitive poloxamer as an anti-adhesive and primary packing material compared with the control using no packing is needed.

Rapid and safe learning of robotic gastrectomy for gastric cancer: multidimensional analysis in a comparison with laparoscopic gastrectomy

BACKGROUND

The learning curve of robotic gastrectomy has not yet been evaluated in comparison with the laparoscopic approach. We compared the learning curves of robotic gastrectomy and laparoscopic gastrectomy based on operation time and surgical success.

METHODS

We analyzed 172 robotic and 481 laparoscopic distal gastrectomies performed by single surgeon from May 2003 to April 2009. The operation time was analyzed using a moving average and non-linear regression analysis. Surgical success was evaluated by a cumulative sum plot with a target failure rate of 10%. Surgical failure was defined as laparoscopic or open conversion, insufficient lymph node harvest for staging, resection margin involvement, postoperative morbidity, and mortality.

RESULTS

Moving average and non-linear regression analyses indicated stable state for operation time at 95 and 121 cases in robotic gastrectomy, and 270 and 262 cases in laparoscopic gastrectomy, respectively. The cumulative sum plot identified no cut-off point for surgical success in robotic gastrectomy and 80 cases in laparoscopic gastrectomy. Excluding the initial 148 laparoscopic gastrectomies that were performed before the first robotic gastrectomy, the two groups showed similar number of cases to reach steady state in operation time, and showed no cut-off point in analysis of surgical success.

CONCLUSIONS

The experience of laparoscopic surgery could affect the learning process of robotic gastrectomy. An experienced laparoscopic surgeon requires fewer cases of robotic gastrectomy to reach steady state. Moreover, the surgical outcomes of robotic gastrectomy were satisfactory.

Assessment of nurses' nutritional knowledge regarding therapeutic diet regimens

Metabolic diseases and cardiovascular disease (CVD), the incidence of which is currently increasing in Korea, can be managed well with dietary education and modification. However, it has yet to be established whether nurses have sufficient knowledge to impart appropriate nutritional counseling to patients with these diseases. Our study involved 506 nurses working at Asan Medical Center, Samsung Medical Center, and Seoul National University Hospital between March and May, 2006. The questionnaire was comprised of 42 diet-related questions pertaining to diabetes, obesity, and CVD. Nurses' correct-response rate for overall nutritional knowledge was worse than reported in Western countries (58.4%), and particularly so with regard to obesity and CVD. Although many nurses were aware of the therapeutic aspects of nutrients in relation to CVD, most of them had limited knowledge about low-cholesterol diets and sources of water-soluble fiber, fatty acids and the specific food items that prevent CVD. Our results suggest that there is an urgent need to update the contents of nutrition education for nurses to reflect the current changes in the Korean diet and the increasing incidence of metabolic diseases and CVD.

Oncocytoma of the spinal cord causing paraplegia – a case report

STUDY DESIGN

Case report.

OBJECTIVES

To describe a rare case of oncocytoma arising from the spinal cord in a 40-year old woman.

SETTING

Republic of Korea.

METHODS

The patient's history, physical examination, radiological and pathological findings were reviewed.

RESULTS

A 40-year-old woman presented with 3-month history of low back pain. Magnetic resonance imaging revealed an intradural extramedullary mass located between L1 and L4. She refused any surgical treatment and so was discharged. At 10 days after discharge, an emergency operation was performed because of sudden paralysis in both lower extremities. The confirmed diagnosis is oncocytoma. At 4 months after surgery, the patient failed to obtain neurological recovery from complete paraplegia.

CONCLUSIONS

Since the progression of an intradural extramedullary mass that shows minor neurological symptoms can lead to complete paraplegia in a short time, close observation and early surgical decompression are necessary.

A dominant antigenic region of the hantaan virus nucleocapsid protein is located within a amino-terminal short stretch of hydrophilic residues

The nucleocapsid (N) protein of the Hantaan virus (HTNV) is a major viral antigen that induces a strong antibody response during the acute phase of infection. By immunoblot analyses of the recombinant N proteins using human sera of the hemorrhagic fever with renal syndrome (HFRS), we have confirmed previous finding by other investigators of the presence of a highly antigenic region near the amino terminus of the HTNV N protein. We have further located the antigenic region within a short stretch of hydrophilic sequences between the 26 and the 46th amino acid residues. The recombinant glutathione S-transferase fusion proteins containing this region was expressed as a soluble form in a large quantity in Escherichia coli, and purified by a single-step affinity chromatography. The recombinant antigen also showed a similar, but a weaker reactivity with human antisera to Seoul virus (SEOV), the virus most closely related to HTNV.

The analysis of Plasmodium vivax Duffy receptor binding domain gene sequence from resurgent Korea isolates

The Duffy binding domain gene structures of Plasmodium vivax facilitate the invasion of erythrocytes. Human erythrocytes that lack Duffy blood group antigens are resistant to invasion by P. vivax. We have sequenced the Duffy binding domain gene from eight P. vivax isolates collected from malaria cases in South Korea. When compared to isolates from other regions in the world, the amino acid sequences of the Korean isolates showed unique variations in region II. From 606 sequenced amino acids, 32 variations were found. Of these, three variations were regularly found in positions 424, 437 and 503 of the Sal-1 amino acid sequence. In region III, six isolates had a loss of the 30 bp (FAESTKSAE) insert. However, six isolates had 6 bp (SD) inserts at the end of region III. Two cases had a reverse pattern. Our results suggest that the P. vivax currently found in South Korea are unique when compared to other isolates and can be divided, by the analysis of their molecular structure, into two strains.

Protease activity and host cell binding of the 42-kDa rhoptry protein from Toxoplasma gondii after secretion

Three proteases were identified in the excretory/secretory proteins (ESP) from Toxoplasma gondii by the gelatin acrylamide gel electrophoresis (GAGE), of which the molecular masses were 80, 70, and 42 kDa. One of the proteases with 42 kDa was reactive to a monoclonal antibody (mAb), Tg786 clone, which was localized in the rhoptry of T. gondii by immunohistochemistry. The protease was maximally active at the pH range between 7.5 and 8.5, and was sensitive to inhibition by TPCK and EGTA. The gelatinolytic activity of the protease was dependent on the concentration of calcium ion. The protease was active only in the millimolar ranges of calcium but not in micromolar ranges, implicating that the secretion is critical event for the activation of the protease. The secreted protease was shown to bind to the host cells upon Western blot and immunofluorescence analysis. It is suggested that the protease may target to the plasma membrane of the host cells, which provides appropriate environment for the entry of the parasite into host cells. The mAb (Tg786) of T. gondii also reacted with a protein of the same size and equivalent locality of rhoptry in Neospora caninum, a similar Apicomplexan protozoa, suggesting that secreted protease mediates a common function in the mechanism of entry into host cells.

Molecular genetic analysis of reovirus isolated in Korea

Reovirus isolates from human, striped-field mouse (Apodemus agrarius) and Korean field mouse (A. peninsulae) in Korea showed extensive variability in the patterns of electrophoretic migration of the double-stranded RNA (dsRNA) genome segments. Hemagglutination inhibition (HI) test was performed for serotype determination of 12 reovirus isolates. To clarify genetic diversity and molecular phylogeny of Korean reoviruses, L1, S3 and S4 genomic segments of reoviruses were amplified by RT-PCR and directly sequenced. Among 12 reovirus strains, 9 strains were type 3 and 3 strains were type 2. The L1 was highly conserved showing 91.5-100%, 94.7-100% similarities among Korean isolates, and 77.5-97.9%, 92.6-96.8% similarities compared to other reference strains of each genotypes at nucleotide and amino acid levels, respectively. In S3 and S4 segments, 84.4-99.3%, 72.3-99% nucleotide sequence similarities and 92-99.3%, 89.1-98.4% amino acid sequence similarities among Korean isolates were observed, and 70.8-93.9%, 72.3-98.7% nucleotide sequence similarities and 81.8-100%, 88.3-97.7% amino acid sequence similarities compared with other reference strains of each genotype were observed, respectively. Phylogenetic analyses based on the S3 and S4 nucleotide sequences indicate that genotypes of reovirus are more related with geographic differences rather than host species or date of isolation.

Molecular cloning and characterization of peroxiredoxin from Toxoplasma gondii

A cDNA of 1.1 kb comprising the gene encoding the peroxiredoxin of Toxoplasma gondii (TgPrx) has been cloned. The open reading frame of 591 bp was translated into a protein of 196 amino acids with a molecular mass of 25 kDa. Conserved 2 cysteine domains of Phe-Val-Cys-Pro and Glu-Val-Cys-Pro indicated TgPrx belonged to 2-Cys Prx families. TgPrx showed the highest homology with that of Arabidopsis thaliana by 53.9% followed by Entamoeba histolytica with 39.5% by the amino acid sequence alignment. Polyclonal antibody against recombinant TgPrx detected 25 kDa band in T. gondii without binding to host cell proteins. TgPrx was located in the cytoplasm of T. gondii extracellularly or intracellularly by immunofluorescence assay. The expression of TgPrx was increased as early as 30 min after the treatment with artemisinin in the intracellular stage, while no changes in those of host Prx I and TgSOD. This result implies that TgPrx may function as an antioxidant protecting the cell from the attack of reactive oxygen intermediates. It is also suggested that TgPrx is a possible target of chemotherapy.

Molecular epidemiology of hepatitis A virus in Korea

BACKGROUND

The prevalence of antibodies for hepatitis A virus (anti-HAV) in adolescents and young adults has decreased remarkably following the economic growth in Korea. As a result, this age group has a high risk for HAV infection paradoxically, and over 1500 cases of clinically overt hepatitis A occurred in 1998. Human isolates of hepatitis A virus (HAV) are categorized within four genotypes (I, II, III, and VII). In some geographic regions, closely related isolates cluster, suggesting endemic spread of the virus, while in other regions multiple genotypes circulate. Virtually no data are available with regard to the genetic relatedness of Korean strains of HAV.

METHODS AND RESULTS

A 168 base pair segment encompassing the putative VP1/2A junction of the HAV genome was amplified by RT-PCR and sequenced in sera of 18 Korean patients with a sporadic form of acute hepatitis A. Pairwise comparisons of the nucleic acid and amino acid sequences of 18 Korean isolates with one another revealed that the Korean isolates showed > 94.6% and > 96.4% identity, respectively. All of the 18 Korean isolates clustered within genotype IA, irrespective of the geographic locations and the time that hepatitis occurred. Unique amino acid sequence changes that had never been reported in genotype IA were found in nine of the 18 isolates. These changes were Gln-->Ser and Lys-->Arg in 2A-19 and 2A-10 amino acid positions.

CONCLUSION

The presence of single genotype and unique mutations may be related with the circulation of endemic HAV over a long period of time in Korea.

The analysis of circumsporozoite-protein gene sequences from South Korean isolates of Plasmodium vivax

The amino-acid sequences corresponding to the circumsporozoite protein (CSP) of Plasmodium vivax fall into two main types, VK210 and VK247, each of which has a characteristic tandem repeat. When the repetitive domains of the CSP gene from six isolates of P. vivax from South Korea were sequenced they were found to show a total of 20 tandem amino-acid repeats, and repeat patterns that are regular and distinct from those of other P. vivax isolates. The amino-acid sequences of the South Korean parasites were found to be most similar to those of three isolates from China (CH-3, CH-4, and CH-5) and, particularly, to one from North Korea. A sequence (AGGNAANKKAEDAGGNA) and two repeats of the sequence GGNA found in the North Korean parasites were found in all six isolates from South Korea. The South Korean parasites investigated appear phylogenetically identical and unique to the Korean peninsula.

Genetic diversity of Apodemus agrarius-borne hantaan virus in Korea

Hantaan (HTN) virus, the etiologic agent of clinically severe hemorrhagic fever with renal syndrome (HFRS), was first isolated in 1976 from lung tissues of striped field mice (Apodemus agrarius) captured in Songnae-ri, Kyungki-do, Korea. To clarify the genetic diversity and phylogenetic relationship among Korean strains of HTN virus, viral sequences of the partial S and M segments were amplified from lung tissues of 24 seropositive striped field mice captured between 1989 and 1998 at 11 sites in South Korea. The 771-nucleotide (nt) S segment sequences (coordinates 432 to 1202) of HTN virus strains from Yangju-kun differed by 10 to 40 nt (1.3 to 5.2%) from virus strains from Pocheon-kun, Songnae-ri and Nonsan-kun. Similar degrees of genetic variation were found in the G1 and G2 glycoprotein-encoding M segment. Phylogenetic trees, based on the partial S and M segments and generated by the maximum parsimony and neighbor-joining methods, demonstrated that virus strains from various geographic regions in South Korea showed a tendency to form two phylogenetic subgroups and were evolutionarily distinct from HTN virus strains from the People's Republic of China.

Instrumental and bioanalytical measures of persistent organochlorines in blue mussel (Mytilus edulis) from Korean coastal waters

Blue mussels (Mytilus edulis) collected from 34 locations along the south and east coast of Korea were analyzed for polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides. Maximum concentrations of PCBs and total OC pesticides were 98.5 and 20.5 ng/g, wet weight, respectively. Extracts were fractionated by Florisil chromatography and each fraction was screened for dioxin-like activity in vitro, using recombinant rat hepatoma cells (H4IIE-luc). Fraction 2 (F-2), which contained hexachlorocyclohexanes, chlordanes, p,p'-DDD, and p,p'-DDT, generally elicited significant dioxin-like activity compared to control, whereas Fraction 1 (F-1), which contained PCBs, p,p'-DDE, and hexachlorobenzene, did not. The greatest magnitude of dioxin-like response observed was 44% of the maximum response elicited by a 2,000 pM 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) standard. The relatively low magnitudes of dioxin-like response observed for F-1 samples were consistent with the relatively low PCB concentrations. At concentrations equal to the maximum observed in the mussel samples, neither individual OC pesticides nor a mixture of OC pesticides yielded a significant dioxin-like response in the H4IIE-luc assay. Thus, the concentrations of OC pesticides in F-2 did not appear to have accounted for the dioxin-like activity observed. This suggests the presence of unidentified and/or unknown, acid-stable, dioxin-like compounds in F-2. This study suggests that in vitro bioassays are useful in assessing the contamination of mussels collected from coastal marine locations.

Phylogenetic analysis of the small hydrophobic (SH) gene of mumps virus in Korea: identification of a new genotype

Viral RNAs extracted from fifteen mumps virus isolated from throat swab, saliva, blood, urine or CSF during mumps epidemics between 1997-1998 in Korea were amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) and compared by nucleotide sequencing of the small hydrophobic (SH) gene. The deduced amino acid sequences of the SH gene were aligned with the published sequences of mumps virus isolated in different geographic areas. A comparison of the SH gene of mumps viruses in Korea indicated 96.2-100% and 91.2-100% similarity at the nucleotide and amino acid levels, respectively. Phylogenetic analysis, using the neighbor-joining method, showed that Korean mumps virus strains formed a genetically distinct monophyletic group from previously reported genotypes based on the 315-bp length nucleotide and 57 deduced amino acid sequences of the SH gene, and possibly be designated as a new genotype (I).

Cloning and expression of a cysteine proteinase gene from Paragonimus westermani adult worms

A gene encoding a cysteine proteinase from Paragonimus westermani has been cloned and expressed in Escherichia coli. The cysteine proteinase cDNA fragment was amplified by reverse transcription-polymerase chain reaction (RT-PCR) using degenerate oligonucleotide primers derived from the conserved active site of the cysteine proteinase. The 5' and 3' regions of the gene were amplified using a PCR technique for the rapid amplification of cDNA ends. The cloned gene has an open reading frame of 687 bp and deduced amino acid sequence of 229. Sequence analysis and alignment showed significant homologies with the eukaryotic cysteine proteinases and conservation of the Cys, His, and Asp residues that form a catalytic triad. Analysis of the expressed protein on sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that the molecular weight of the protein was approximately 28.5 kDa. The expressed protein reacted with the sera of patients with paragonimiasis but not with the sera of fascioliasis and clonorchiasis. These results suggest that the expressed protein may be valuable as a specific diagnostic material for the immunodiagnosis of paragonimiasis.

Isolation of a cDNA encoding a 31-kDa, pathogenesis-related 5/thaumatin-like (PR5/TL) protein abundantly expressed in apple fruit (Nalus domestica cv. Fuji)

A fruit-specific and pathogenesis-related 5/thaumatin-like (PR5/TL), 31-kDa protein was isolated by 2D-PAGE from fully-grown apples (Malus domestica cv. Fuji) and named Mdtl1 (Malus domestica thaumatin-like protein 1). Using the N-terminal sequence of the protein, the full-length cDNA encoding Mdtll was isolated. The cDNA clone (Mdtl1) consists of 944 bp with an open reading frame (ORF) of 744 bp encoding a protein of 247 amino acids. The deduced amino acid sequence of Mdtl1 shows high similarity to the sequences of PR5/TL proteins. Mdtl1 is a slightly acidic protein with a putative signal peptide and a putative N-glycosylation site, and lacks a C-terminal extension. This suggests that Mdtl1 is an apoplastic glycoprotein. Results of northern blotting indicated that expressions of Mdtl1 are developmentally regulated. Southern blot analysis showed that Mdtl1 may be present as a single copy, and there exist other genes closely related to Mdtl1 in the apple genome.

Analysis of Plasmodium vivax merozoite surface protein-1 gene sequences from resurgent Korean isolates

The merozoite surface protein-1 (MSP-1) of Plasmodium vivax exhibits great antigenic diversity among different isolates of this parasite. This antigen is a useful genetic marker for studying the polymorphism of natural P. vivax parasite populations. One or more of these populations has been responsible for resurgent malaria now occurring in Korea. This paper reports the analysis of a highly polymorphic region between interspecies conserved blocks 5 and 6 of the MSP-1 gene, using the polymerase chain reaction to amplify the DNA fragment encompassing these regions from 25 Korean isolates, followed by sequencing. Almost all amino acid sequences of Korean isolates were nearly identical to that of Thai isolates TD525A (96.6-99.7%) and TD424 (96.3-99.5%), and very similar to that of the France-Belem strain when compared with other isolates (Sal-1, Sri Lanka, and Colombia). Interallelic recombination was found in the poly-Q repeat and a Sal-1 type amino acid structure was observed in all isolates. This study shows that the MSP gene nucleotide sequence of resurgent P. vivax in Korea is most similar to that of Thai isolates; however, the Korean strains are phylogenetically unique.

Failure to demonstrate Borna disease virus genome in peripheral blood mononuclear cells from psychiatric patients in Korea

RNA, extracted from peripheral blood mononuclear cells (PBMC) obtained from 81 Korean psychiatric patients (39 with schizophrenia, 33 with bipolar affective disorders and nine with major depression), was analyzed for a 391-nucleotide, highly conserved region of the p24 protein-encoding ORF II of Borna disease virus (BDV), using nested reverse transcription-polymerase chain reaction (RT-PCR). BDV genomic RNA was not detected in PBMC from any of the 81 Korean psychiatric patients. These data do not support an etiologic association between BDV infection and neuropsychiatric disorders in humans.

Infection rate of Leptospira interrogans in the field rodent, Apodemus agrarius, in Korea

Leptospirosis has significantly decreased in Korea since 1988, following the leptospiral vaccination programme initiated in 1988. Whether this wholly explains the decreased incidence is uncertain. As an initial step to answer this question, infection rates of Leptospira interrogans in field rodents, Apodemis agrarius, were examined and compared with previous data. Two hundred and twenty-two A. agrarius were captured during October-December 1996. Spirochaetes were isolated from 22 (9.9%) and leptospiral DNA was detected in an additional 6 rodents (12.6%). Subsequent microscopic agglutination tests (MAT) classified all these isolates as L. interrogans serogroup Icterohaemorrhagiae serovar lai. The above data did not significantly differ from previous surveys in 1984-7. There was no significant change of L. interrogans infection in field rodents following the introduction of the vaccination programme in Korea. Further studies are needed to determine the role of human vaccination in reducing incidence.

Slow dendritic transport of dissociated mouse hippocampal neurons exposed to aluminum

We determined the influence of aluminum on dendritic transport, using an in vitro system of dissociated mouse hippocampal neurons. Newly synthesized RNA from dissociated mouse hippocampal neurons was more slowly transported into dendrites in the presence of aluminum chloride when compared to those without the addition of aluminum chloride to the culture medium. Suppression of dendritic transport of newly synthesized RNA may be responsible for the dendritic degeneration observed in aluminum neurotoxicity, eventually leading to neuronal degeneration.

Human T-cell lymphotropic virus type I in Iranian-born Mashhadi Jews: genetic and phylogenetic evidence for common source of infection

High prevalence of human T-cell lymphotropic virus type I (HTLV-I) infection and disease has been identified among Iranian-born Mashhadi Jews, an ethnically segregated, highly inbred population. To determine the origin and genetic diversity of HTLV-I in this group, 1,039 bp spanning selected regions of the HTLV-I gag, pol, env and pX genes were enzymatically amplified and sequenced directly from DNA of five Mashhadi Jews (three with spastic myelopathy and two asymptomatic carriers). Alignment and comparison of these sequences with cosmopolitan and Australo-Melanesian topotypes of HTLV-I indicated that the HTLV-I strains from Mashhadi Jews, which were > or = 99.9% identical among themselves, exhibited considerable sequence similarity (> or = 99%) to HTLV-I strains from southern India, suggesting a common source of infection. Phylogenetic analysis, using the maximum parsimony method, was consistent with a single-source introduction of HTLV-I into the Mashhadi Jewish community.

Sequence and phylogenetic analyses of human T cell lymphotropic virus type 1 from a Brazilian woman with adult T cell leukemia: comparison with virus strains from South America and the Caribbean basin

Human T cell lymphotropic virus type 1 (HTLV-1) is endemic in South America and the Caribbean basin. To clarify the genetic and phylogenetic relationship between an HTLV-1 strain isolated from a Brazilian woman with adult T cell leukemia and viral isolates from elsewhere in South America and from other geographic regions, selected regions of the gag, pol, env, and pX genes were amplified and directly sequenced. The overall sequence similarities between the Brazil-R-1 strain and the Japanese prototype ATK strain were 98.7% based on 1,295 nucleotides and 99.1% based on 429 amino acids. Phylogenetic analysis indicated that strain Brazil-R-1 clustered with other Brazilian and South American HTLV-1 isolates and was more closely related to Caribbean isolates from Martinique and Guadeloupe than to virus strains from other geographic regions. These data suggest a common source of HTLV-1 infection in the Caribbean basin and South America.

Genotyping of human T cell lymphotropic virus type I using Australo-Melanesian topotype-specific oligonucleotide primer-based polymerase chain reaction: insights into viral evolution and dissemination

Sequence variants of human T cell lymphotropic virus type I (HTLV-I), genetically distinct from cosmopolitan strains of HTLV-I from Japan, the Americas, the Caribbean, and Africa, have been discovered among Melanesians in Papua New Guinea and the Solomon Islands and among Australian aboriginals. By using oligonucleotide primer pairs derived from sequences unique to the gp46- and gp21-encoding regions of the env gene of the Melanesian HTLV-I variants, HTLV-I strains from widely separated geographic regions could be grouped into either of two major geographic-specific genotypes or topotypes: Australo-Melanesian and cosmopolitan. These primers did not permit amplification of the corresponding env gene regions in strains of simian T cell lymphotropic virus type I from Asia and Africa. Phylogenetic analysis also supported two distinct lineages, consistent with evolution of HTLV-I in Australia and Melanesia independent from that in other parts of the world.

Genetic evidence for a hantavirus enzootic in deer mice (Peromyscus maniculatus) captured a decade before the recognition of hantavirus pulmonary syndrome

To determine if the emergence of hantavirus pulmonary syndrome in the United States was a consequence of recent amino-acid altering mutations and/or genetic reassortment with pathogenic hantaviruses, we examined lung and spleen tissues from seropositive deer mice trapped in August 1983 in Mono County, California, for hantaviral RNA by reverse transcriptase-directed polymerase chain reaction. Alignment and comparison of 1485 nucleotides of the S and M genomic segments enzymatically amplified from these tissues indicated that these deer mice harbored a hantavirus which was genetically similar, differing by less than 2% at the deduced amino-acid level, to the hantavirus implicated in cases of hantavirus pulmonary syndrome occurring in the Four-Corners region of New Mexico, Arizona, Utah, and Colorado in 1993. The peromyscine rodent-borne hantaviruses were, in turn, genetically distinct from other well-characterized hantaviruses, diverging by approximately 30% from Prospect Hill and Puumala viruses at the nucleotide and amino acid levels. Phylogenetic analysis using the maximum parsimony, neighbor-joining, and unweighted pair-group methods indicated that the Peromyscus-derived hantavirus shared a common ancestry with arvicolid rodent-borne hantaviruses. Overall congruency of the phylogenetic trees based on the S and M genomic sequences supported the evolutionary position of the peromyscine rodent-borne hantaviruses. Our data also establish the existence of a hantavirus enzootic in deer mice long before the recognition of hantavirus pulmonary syndrome in the United States.

Genetic and phylogenetic analyses of human T-cell lymphotropic virus type I variants from Melanesians with and without spastic myelopathy

Molecular variants of human T-cell lymphotropic virus type I (HTLV-I) have been isolated recently from lifelong residents of remote Melanesian populations, including a Solomon Islander with tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM) or HTLV-I myeloneuropathy. To clarify the genetic heterogeneity and molecular epidemiology of disease-associated strains of HTLV-I, we enzymatically amplified, then directly sequenced representative regions of the gag, pol, env, and pX genes of HTLV-I strains from Melanesians with and without TSP/HAM, and aligned and compared these sequences with those of HTLV-I strains from patients with TSP/HAM or adult T-cell leukemia/lymphoma and from asymptomatic carriers from widely separated and culturally disparate populations. Overall, the HTLV-I variant from the Solomon Islander with TSP/HAM, like HTLV-I strains from asymptomatically infected Melanesians, diverged by approx 7% from cosmopolitan HTLV-I strain. No disease-specific viral sequences were found. Gene phylogenies, as determined by the unweighted pair-group method of assortment and by the maximum parsimony method, indicated that the Melanesian and cosmopolitan strains of HTLV-I have evolved along separate geographically dependent lineages, one comprised of HTLV-I strains from Papua New Guinea and the Solomon Islands, and the other composed of virus strains from Japan, India, the Caribbean, Polynesia, the Americas, and Africa. The total absence of nonhuman primates in Papua New Guinea and the Solomon Islands precludes any possibility that the Melanesian HTLV-I strains have evolved recently from the simian homolog of HTLV-I.

Genetic analysis and molecular phylogeny of simian T-cell lymphotropic virus type I: evidence for independent virus evolution in Asia and Africa

Type C retroviruses, designated simian T-cell lymphotropic virus type I (STLV-I), have been isolated from several genera of Old World monkeys and apes, but not from New World monkeys and prosimians. To determine the genomic diversity and molecular evolution of STLV-I and to clarify their genetic relationship to human T-cell lymphotropic virus type I (HTLV-I), we enzymatically amplified, then directly sequenced selected regions of the gag, pol, env, and pX genes of STLV-I strains from Asia and Africa. STLV-I strains Si-2, Matsu, and JM86 from Japanese macaques, which exhibited sequence similarities ranging from 98.5 to 99.8% among themselves, diverged by 12.9 to 13.3% from STLV-I strain MM39-83 from a naturally infected rhesus macaque, by 9.7 to 11.2% from STLV-I strains from Africa, and by 8.8 to 11.2% from HTLV-I strains originating in Japan, India, Africa, the Caribbean, the Americas, Polynesia, and Melanesia. By contrast, the interspecies nucleotide sequence similarity among African STLV-I strains from green monkey, yellow baboon, sooty mangabey, and common chimpanzee was remarkably high, ranging from 96.9 to 97.4%, and these STLV-I strains diverged by only 2.2 to 2.8% from HTLV-I strain EL from equatorial Zaire. Phylogenetic trees constructed by using the neighbor-joining and maximum parsimony methods indicated that the Asian STLV-I strains diverged from the common ancestral virus prior to African STLV-I and cosmopolitan and Melanesian HTLV-I strains. Thus, our data are consistent with an archaic presence of STLV-I in Asia, probably predating macaque speciation, with subsequent independent virus evolution in Asia and Africa.

Sequence analysis of human T cell lymphotropic virus type I strains from southern India: gene amplification and direct sequencing from whole blood blotted onto filter paper

Human T cell lymphotropic virus type I (HTLV-I) infection in India has been found to be associated with adult T cell leukaemia/lymphoma (ATLL) and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) among life-long residents of southern India. To examine the heterogeneity of HTLV-I strains from southern India and to determine their relationship with the sequence variants of HTLV-I from Melanesia, 1149 nucleotides spanning selected regions of the HTLV-I gag, pol, env and pX genes were amplified and directly sequenced from DNA extracted from whole blood blotted onto filter paper and from peripheral blood mononuclear cells, obtained from one patient with HAM/TSP, two with ATLL and eight asymptomatic carriers from Andhra Pradesh, Kerala and Tamil Nadu. Sequence alignments and comparisons indicated that the 11 HTLV-I strains from southern India were 99.2% to 100% identical among themselves and 98.7% to 100% identical to the Japanese prototype HTLV-I ATK. The majority of base substitutions were transitions and silent. No frameshifts, insertions, deletions or possibly disease-specific base changes were found in the regions sequenced. The observed clustering of the Indian HTLV-I strains with those from Japan, as determined by the maximum parsimony method, suggested a common source of HTLV-I infection with subsequent parallel evolution. Amplification of DNA from blood specimens collected on filter paper may be useful for the study of other blood-borne pathogens.

Interfamilial and intrafamilial genomic diversity and molecular phylogeny of human T-cell lymphotropic virus type I from Papua New Guinea and the Solomon Islands

To determine the interstrain genomic diversity and molecular phylogeny of the recently identified variants of human T-cell lymphotropic virus type I (HTLV-I) in Melanesia, we enzymatically amplified, then directly sequenced representative regions of the gag, pol, and env genes of HTLV-I strains from 10 members of four families, including one family from Papua New Guinea and three families from the Solomon Islands. When aligned and compared to a Japanese strain of HTLV-I (ATK), the Melanesian HTLV-I strains differed by 7.6 to 8.7% in the gag, 7.1 to 9.3% in the pol, and 7.3 to 8.2% in the env gene regions. Based on 931 nucleotides, the overall sequence divergence of the 10 Melanesian HTLV-I strains from HTLV-I ATK was 7.3 to 8.1% (68 to 75 base substitutions). The intrafamilial genetic heterogeneity among these virus strains was nil to 0.2%, while the interfamilial sequence variation between HTLV-I strains from the Solomon Islands and those from Papua New Guinea was 3.4 to 4.2%, and the genetic heterogeneity among virus strains from the three Solomon Islands families was 0.2 to 0.9%. Using the maximum parsimony and neighbor-joining methods, phylogenetic analysis indicated that the HTLV-I strains from Papua New Guinea and the Solomon Islands formed a monophyletic group and that the Melanesian and cosmopolitan strains of HTLV-I have evolved along two major geographically dependent lineages.

Fibrils in brain of Rocky Mountain elk with chronic wasting disease contain scrapie amyloid

Chronic wasting disease (CWD), a progressive, fatal neurological disorder of captive mule deer and Rocky Mountain elk, is characterized neuropathologically by spongiform change in the neuropil, intraneuronal vacuolation and astrocytic hypertrophy and hyperplasia. Recently, scrapie amyloid-immunoreactive plaques have been demonstrated in brain tissues of CWD-affected captive mule deer, Rocky Mountain elk and hybrids of captive mule deer and white-tailed deer. We now report on the presence of abnormal fibrils isolated from brain tissues of Rocky Mountain elk using negative-stain electron microscopy. These fibrils resemble those found in scrapie-infected hamster brain. Furthermore, protein bands with relative molecular masses of 26 to 30 kilodaltons were shown to be immunoreactive to antibodies raised against scrapie amyloid by Western immunoblotting. Immuno-dot blot showed similar reactivity. Our data support the clinical and pathological diagnosis of the disease and provide further evidence that CWD belongs to the subacute spongiform encephalopathies.