CD56+ B-cell Neurolymphomatosis in a Cat

A 16-year-old male Russian blue cat was presented with acute onset of paraparesis of the forelimbs that progressed to tetraparesis. Neurological examination revealed non-ambulatory tetraparesis with decreased postural reactions in all four limbs. Magnetic resonance imaging revealed multifocal nerve root swelling on the right at C6/C7 and C7/T1, while ultrasonography demonstrated swelling of the right brachial plexus. To understand the cause of the nerve swelling, the right musculocutaneous nerve arising from the brachial plexus and the pectoralis muscle were biopsied. Histologically, there was evidence of neurolymphomatosis (neurotropic lymphoma) with Wallerian degeneration and denervation atrophy of myofibres. The neoplastic lymphoid cells expressed CD79a, CD20 and CD56. Based on these findings, a diagnosis of B-cell neurolymphomatosis was made. Expression of CD56, synonymous with neural cell adhesion molecule, is rare in B-cell lymphomas and has not been reported in feline B-cell lymphomas or feline neurolymphomatosis. CD56 expression was suspected to have played an important role in neurotropism of the neoplastic cells in this case.

Fibronectin suppresses lipopolysaccharide-induced liver damage and promotes the cytoprotection abilities of hepatocyte-like cells derived from human bone marrow mesenchymal stem cells

We isolated mesenchymal stem cells (MSCs) from adult human bone marrow. By using reverse-transcription polymerase chain reactions, we confirmed that MSCs possessed the potential to differentiate into hepatocyte-like cells (MSC-HLCs) with the expression of hepatocyte-specific marker genes. We further observed that fibronectin (FN) treatment significantly inhibited lipopolysaccharide (LPS)-induced apoptotic activities in FN-treated MSC-HLCs, as detected by caspase 3 enzyme-linked immunosorbent (ELISA) and terminal dUTP nick-end labeling (TUNEL) assays (P<.05). The FN-treated MSC-HLCs were transplanted into SCID mice with or without LPS injection. This study demonstrated that FN treatment improved liver function repair and survival rates among LPS-treated SCID mice.

Evaluation of wound healing effect on skin-defect nude mice by using human dermis-derived mesenchymal stem cells

We report that human dermis-derived mesenchymal stem cells (hDMSCs) possess differentiation potential of epidermis facilitating wound healing in skin-defect nude mice in combination with the treatment using gelatin/thermosensitive poly N-isopropylacrylamide (pNIPAAm)/polypropylene (PP). The results showed that the rate of cell growth and wound recovery in the hDMSC and gelatin/pNIPAAm/PP-treated group was significantly greater than those in the gelatin/pNIPAAm/PP-treated only group (P < .01). The reepithelialization marker of human pan-cytokeratin was also significantly increased on days 14 and day 21 in the wound site of hDMSCs and gelatin/pNIPAAm/PP-treated group. Furthermore, the stem cell marker of human CD13 gradually decreased during the period of wound healing. In sum, this novel method provided a transferring system for stem cell therapy, maintaining its temperature-sensitive property of easy peeling by lower temperature treatment.

Using gelatin scaffold with coated basic fibroblast growth factor as a transfer system for transplantation of human neural stem cells

Gelatin scaffolds for ex vivo cell cultures are a promising development. These scaffolds can be used as three-dimensional skeletons for cell attachment and culture before transplantation. In this study, we isolated and cultivated neural stem cells from human brain tissues in serum-free medium (DMEM+F12 nutrient). Better neuron growth was observed using the tetrazolium assay (MTT) in the group when basic fibroblast growth factor (bFGF) was coated on the gelatin polymer scaffold. Further development of this nontoxic system may help the future development of transplantation of human neural stem cells.

Using Human Plasma Supplemented Medium to Cultivate Human Bone Marrow–Derived Mesenchymal Stem Cell and Evaluation of Its Multiple-Lineage Potential

The objective of this study was to evaluate the proliferation and the multiple-lineage differentiation capacity when bone marrow mesenchymal stem cells (BMSCs) were cultured short-term in autologous serum/plasma instead of fetal calf serum (FCS). The BMSCs from 12 donors were cultivated individually in 10% autogenic plasma or serum, with or without bFGF and EGF growth factors. Cell proliferation was examined by a Tetrazolium assay (MTT) after passages 1, 3, and 5. A medium supplemented with 10% human plasma or serum was sufficient to propagate BMSCs. However, no significant proliferation was shown when bFGF and EGF (20 ng/mL each) were added into the medium with autologous serum/plasma. We examined, inductions of adipogenesis, osteogenesis, and chondrocytogenesis, as capacities of multiple-lineage differentiation of cultivated BMSCs (passages 8). Differentiation was investigated by both RT-PCR and immunohistochemistry staining (IHC). Qualitative evidence demonstrated the differentiation capacity was preserved in cultivated BMSCs with autologous serum/plasma.

Chronological evolution of IgM, IgA, IgG and neutralisation antibodies after infection with SARS-associated coronavirus

Abstract Serum levels of IgG, IgM and IgA against severe acute respiratory distress syndrome (SARS)-associated coronavirus (SARS-CoV) were detected serially with the use of immunofluorescent antibody assays in 30 patients with SARS. Seroconversion for IgG (mean 10 days) occurred simultaneously, or 1 day earlier, than that for IgM and IgA (mean 11 days for both). IgG could be detected as early as 4 days after the onset of illness. The earliest time at which these three antibodies reached peak levels was similar (mean 15 days). A high IgG level (1:800) could persist for > 3 months. The kinetics of neutralisation antibodies obtained with 100x the tissue culture infective dose (TCID50) of the SARS-CoV TW1 strain in five patients with SARS nearly paralleled those for IgG. There were no significant differences in the kinetics of the IgG, IgM and IgA responses between patients with or without underlying medical disease, steroid or intravenous immunoglobulin therapy, or mechanical ventilation.

The reverse upper arm curved graft with ringed PTFE graft as an alternative vascular access procedure for hemodialysis

AIM

Prosthetic arteriovenous accesses are the last resort after efforts to place autogenous accesses are exhausted. During reimplantation of the graft, it is sometimes not convenient to dissect out the vessels to be grafted, especially around the venous anastomotic site and under local anesthesia.

METHODS

We describe a technique using the ringed PTFE graft for the construction of a reverse upper arm curved graft in 14 patients who had received upper arm grafts previously.

RESULTS

The mean operative time was 61+/-13 minutes, and the follow-up interval extended to 20 months. No infections, pseudoaneurysm formations, or steal syndrome occurred during the follow-up period. The primary patency rate was calculated by Kaplan-Meier analysis, and the primary patency from graft insertion to clotting in the reverse graft was 91% at 3 months, 83% at 6 months, 66% at 9 months, and 57% at 12 months.

CONCLUSION

These results suggest that using the reverse upper arm curved graft during the reimplantation procedure was an alternative prosthetic arteriovenous access with the advantage of less tissue dissection, shorter operation time, and favorable patency rate.

Minimal invasive surgery for resection of parathyroid tumor in the aortopulmonary window

Video-assisted thoracoscopic surgery for parathyroid glands deep in the mediastinum is a safe and successful procedure, but its success depends on accurate localization before operation. Recently, a variety of minimally invasive techniques to approach cardiovascular disease have been proposed to eliminate the morbidity of standard sternotomy. We describe a case involving a 71-year-old woman with persistent hyperparathyroidism resulting from an ectopic mediastinal parathyroid gland, which was removed through an upper sternotomy. The technique has proved safe, effective, and aesthetically acceptable to the patient.

Modified method for epicardial constriction: the electric-Waffle procedure

Residual epicardial constriction after pericardiectomy prevents good results. The Waffle procedure, incising the fibrotic epicardium in a crosshatched manner, is frequently used to release the epicardial constriction. In this report, we describe a modification of the Waffle procedure, which uses the electrocautery unit and watching the standard monitoring equipment for arrhythmia, to perform multiple epicardial incisions.

Flow cytometry compared with indirect immunofluorescence for rapid detection of dengue virus type 1 after amplification in tissue culture

Dengue virus (DV) was detected early in infected mosquito C6/36 cells by using indirect immunofluorescence (IF) in conjunction with flow cytometry. Three fixation-permeabilization methods and three DV serotype 1 (DEN-1)-specific monoclonal antibodies, 8-8 (anti-E), 16-4 (anti-NS1), and 15F3-1 (anti-NS1), were evaluated for the detection of DEN-1 in infected C6/36 cells. We found that these three monoclonal antibodies were capable of detecting DV in C6/36 cells as early as 24 h postinoculation by using a conventional indirect IF stain. Both 8-8 and 16-4 detected DV earlier and showed a greater number of DV-positive cells than 15F3-1. In flow cytometry, 3% paraformaldehyde plus 0.1% Triton X-100 with 16-4, the best fixation-permeabilization method for testing DV, showed higher sensitivity (up to 1 PFU) than indirect IF stain. The higher sensitivity of 16-4 in detecting DEN-1 was found with both IF and flow cytometry. Flow cytometry, which had a sensitivity similar to that of nested reverse transcription-PCR, was more sensitive in detecting DV in the infected mosquito cells 10 h earlier than the conventional IF stain. When clinical specimens were amplified in mosquito C6/36 cells and then assayed for DV using flow cytometry and conventional virus isolation at day 7 postinfection, both methods had 97.22% (35 out of 36) agreement. Moreover, among 12 positive samples which were detected by conventional culture method, the flow cytometry assay could detect DV in 58.33% (7 out of 12) of samples even at day 3 postinfection. In conclusion, both monoclonal antibodies 8-8 and 16-4 can be used for the early detection of DEN-1-infected C6/36 cells, with 16-4 (anti-NS1) being the best choice for the rapid diagnosis of DV by both the IF staining and flow cytometry methods.

Seroprevalence and demographic characteristics of HTLV-I among blood donors in Taiwan: 1996-1999

Screening for the human T-cell lymphotropic virus type I (HTLV-I) and-II in blood donors was implemented in Taiwan beginning in February 1996. The purpose of the present study was to investigate the changes in HTLV-I seroprevalence in all unpaid blood donors in Taiwan during the period from February 1996 to December 1999 and to determine the influence of age and sex on the HTLV-I seropositivity of donors. HTLV-I and HTLV-II screening was performed using combined HTLV-I/II immunoassay. Repeated reactive samples were confirmed by Western blot analysis. Of a total of 3,701,087 donors in all 6 blood centers in Taiwan, 2,311 (0.058%) were seropositive for HTLV-I. The HTLV-I seropositivity was 0.130%, 0.063%, 0.044%, and 0.032% in the years 1996, 1997,1998, and 1999, respectively. There was a linear increase of HTLV-I seropositivity with advancing age. The HTLV-I carrier rate for female donors was twice that for the male donors. Ninty-seven percent of HTLV-I seropositive results came from first-time donors. Our findings suggest that Taiwan is a low-prevalence nonendemic area for HTLV-I infection. The large-scale HTLV-I screening program has decreased HTLV-I seropositivity among blood donors and is useful for preventing HTLV-I transmission via blood transfusion.

Chyle withdrawal from an implanted port in occult innominate vein stenosis

Totally implantable venous devices are widely used for chemotherapy and parenteral nutrition. There have been many device-associated complications reported in the literature. Herein, we report a case of chyle withdrawal from an implanted port that occurred secondary to occult innominate vein stenosis in a patient receiving chemotherapy for rectal cancer with lung metastasis. The port remained patent and functioning well after balloon angioplasty.

Immunogenicity and fecal poliovirus excretion in sequential use of inactivated and oral poliovirus vaccines

BACKGROUND AND PURPOSE

Though inoculation with inactivated poliovirus vaccine (IPV) is advocated, sequential use of IPV and live oral poliovirus vaccines (OPV) has many advantages. This study aimed to define the immunogenicities of IPV and OPV in Taiwanese children after the use of a sequential schedule of IPV-OPV and also to determine whether prior IPV inoculation hampers the fecal passage of OPV.

METHODS

Fifty-nine infants were recruited to receive IPV-OPV sequential vaccinations consisting of IPV given at the ages of 2 and 4 months and OPV given at the ages of 6 and 18 months. Blood samples were taken at ages 2, 6, 18, and 19 months for antibody determination, and stool samples were collected to isolate vaccine strains of poliovirus after the second dose of OPV, at the age of 18 months.

RESULTS

None of the children had severe systemic or local reactions. Protective antibodies were detected in all infants at the age of 6 months, 2 months after the second IPV dose. The antibody titers were augmented at the age of 19 months, 1 month after the booster dose of OPV. Stool samples collected 7 days after the second dose of OPV yielded at least one type of poliovirus in 9 of 18 children. Analysis of stool samples revealed that poliovirus was excreted by the 28th day in only two of the children.

CONCLUSIONS

Our study showed that both IPV and OPV exhibit immunogenicity in Taiwanese children. Side effects of an IPV-OPV sequential schedule were mild and infrequent. Viral shedding in stools after OPV vaccination was preserved in a substantial proportion of subjects. These findings suggest that this sequential vaccination schedule can maintain herd immunity.

Specific IgA antibodies to recombinant early and nuclear antigens of Epstein-Barr virus in nasopharyngeal carcinoma

Nasopharyngeal carcinoma is a common cancer in Taiwan. The Epstein-Barr virus (EBV) is closely associated with nasopharyngeal carcinoma. The sera of patients with nasopharyngeal carcinoma have IgA antibodies to a variety of EBV latent and replicated antigens. Recently, an enzyme-linked immunosorbent assay (ELISA) kit, combining both the EBV early antigen (EA) and nuclear antigen (EBNA-1) became commercially available. The purpose of this study was to assess its clinical application. Serum IgA antibodies to the EBV EA and EBNA-1 were measured by using the ELISA kit in various groups of subjects. Fluorescence antibody (FA) tests against EBV viral capsid antigen (VCA) and EA in the IgA and IgG classes were also studied for comparison. The DNA content analysis was also carried out to investigate the association with IgA antibody titres using ELISA. The sensitivity, specificity and accuracy of the ELISA test were 98.1%, 81.8% and 88.7% respectively. It was far better than any FA tests. The IgA antibody titres showed no association with DNA content analysis. Univariate analysis of various factors revealed that IgA antibody titres were statistically correlated to N stage (P = 0.0291) and M status (P = 0.001). However, there was no association with the age, sex, T stage and clinical stage. Multivariate analysis of various factors was found to be statistically significant in patients with T4 (P = 0.0133), N3 (P = 0.0244) or M1 (P = 0.001) respectively. Serial testing of antibody titres in 22 previously untreated patients found a trend of decreasing IgA antibody titres after initial treatment when the tumours disappeared (P = 0.0358). The ELISA kit to identify specific IgA antibodies with the combination of EBV EA and EBNA-1 recombinant antigens has high sensitivity and acceptable specificity and accuracy in the diagnosis of nasopharyngeal carcinoma. This assay should be useful for early diagnosis and mass screening of patients.

Genetic characterization of the rotaviruses associated with a nursery outbreak

G1P[6] rotaviruses were demonstrated previously to be associated with the neonatal nursery outbreak of gastroenteritis in Changhua Christian Hospital that is located in the central region of Taiwan, from September 1994 to May 1995. Meanwhile, rotaviruses were detected in children hospitalized for acute gastroenteritis. Our study characterizes the rotaviruses associated with the nursery outbreak by using genetic approaches. Nucleotide sequence analysis revealed that the VP7 genes of the nursery rotaviruses were distinct from those of the strains circulating in the community. The G1P[6] rotaviruses recovered from the nursery were closely related to another neonatal G1P[6] strain from the northern region of Taiwan in both the VP4 and VP7 genes. The VP4 genes of these nursery strains differed from those of the P[6] human reference strains 1076, M37, RV3, and ST3. Apparently, these nursery rotaviruses were distinct from the strains circulating in the community and seemed to be a variant when compared with P[6] strains reported previously.

Elevated nitric oxide level in aqueous humor of patients with acute angle-closure glaucoma

Nitric oxide, a noxious and free-radical gas, plays a key role in vasodilatation, inflammation, immunity, and neurotoxicity. Studies have shown that a recently detected NO synthase inducible isoform, found in astrocytes in the optic nerve heads of glaucoma patients, could stimulate excessive production of NO. The purpose of our study was to elucidate the role of NO production in the pathogenesis of glaucoma. We measured the concentrations of NO in aqueous humor from 11 patients with acute angle-closure glaucoma (AACG) and 14 patients with cataract. All samples were collected from patients who were free of any other systemic disease. Utilizing a chemiluminescence assay, we found that in AACG patients the NO levels in aqueous humor samples (83.2 +/- 6.7 microM) were significantly higher than in cataract patients (27.1 +/- 3.6 microM; p < 0.001). We therefore concluded that excessive NO in AACG patients reflects the degree of ocular impairment demonstrated by concomitant retinal cell and optic nerve cell damage.

Intrafamilial transmission and risk assessment of HTLV-I among blood donors in southern Taiwan

The human T-lymphotropic virus type I (HTLV-I) is one of the important etiological agents of adult T-cell leukemia/lymphoma and of HTLV-I associated myelopathy or tropical spastic paraparesis. There is still a lack of data concerning HTLV-I transmission by seropositive carriers in Taiwan. We investigated the patterns of HTLV-I intrafamilial transmission in HTLV-I seropositive blood donors and assessed the risk factors of HTLV-I transmission in relatives of HTLV-I carriers in Taiwan. A total of twenty HTLV-I seropositive donors and their 103 relatives were enrolled. Among those 103 relatives, 40 (38.8%) were seropositive for HTLV-I. Their ages ranged from one to 70 years old with a mean age of 31.0 +/- 1.65 year-old. Three of the ten wives of male carriers were HTLV-I seropositive. However, none of the six husbands of female carriers were HTLV-I seropositive. Mother-to-child vertical transmission was found in nine of 48 (18.8%) tested. Significant risk factors of HTLV-I transmission among relatives of HTLV-I carriers were hospital admission, previous transfusion, breast feeding, anti-HCV seropositivity and female relatives of age >/= 30 with odds ratio (OR) of 9.73, 8.64, 4.36, 8.86 and 4.91, respectively (all p < 0.05). Nonsignificant risk factors of HTLV-I transmission were sharing needles, operation history, HBsAg seropositivity and male relatives of age >/= 30. Our findings suggest that mother-to-child and husband-to-wife transmissions are the important forms of intrafamilial transmission of HTLV-I in Taiwan. Screening for HTLV-I in family members of HTLV-I seropositive blood donors may be warranted.

Infection of human dendritic cells by dengue virus causes cell maturation and cytokine production

Dengue virus (DV) infection is a major problem in public health. It can cause fatal diseases such as Dengue hemorrhagic fever and Dengue shock syndrome. Dendritic cells (DC) are professional APCs required for establishing a primary immune response. Here, we investigated the role of human PBMC-derived DC in DV infection. Using different techniques, including plaque assay, flow cytometry analysis, nested RT-PCR, and confocal microscope and electron microscope examinations, we show that DV can enter cultured human DC and produce virus particles. After entrance, DV could be visualized in cystic vesicles, vacuoles, and the endoplasmic reticulum. The DV-infected DC also showed proliferation and hypertrophy of the endoplasmic reticulum as well as the swollen mitochondria. In addition, the DV-stimulated DC could express maturation markers such as B7-1, B7-2, HLA-DR, CD11b, and CD83. Furthermore, the infection of DC by DV induced production of TNF-alpha and IFN-alpha, but not IL-6 and IL-12. Although DC underwent spontaneous apoptosis in the absence of feeding cytokines, this process appeared to be delayed after DV infection. Our observations provide important information in understanding the pathogenesis of DV infection.

The outcome of shunted hydrocephalic children

BACKGROUND

Neurological sequelae and mental retardation may result from different etiological types of hydrocephalus. The aim of our study is to determine the intellectual development and the "shunt history" of these children with regard to the complications and revision rates.

METHODS

We reviewed the medical history of non-tumoral pediatric hydrocephalic patients who had received first shunt insertions between 1983 and 1997 and had been regularly followed up at the out-patient clinics of Taipei Veterans General Hospital. These patients were categorized into five different etiological groups. Their intelligence test scores and the surgical morbidity encountered over this period were used as the main outcome measures.

RESULTS

Out of the seventy-three patients, post-meningitis hydrocephalus patients had the significantly highest shunt revision rate (2.50 +/- 0.82, p = 0.01). They also showed retardation in IQ scores, but the different was not significant when compared with other groups. The results of IQ tests were not related to either the age of initial shunt insertion (p = 0.461) or revision rates (p = 0.292). For physical disabilities, post-meningitis hydrocephalic patients showed-highest incidence of epilepsy (40%) while hydrocephalic patients associated with myelomeningocele had the highest incidence of motor deficits (56.25%).

CONCLUSIONS

Childhood hydrocephalic patients had different developmental neuroimpairments with respect to different etiologies. This study provides information about the physical and mental outcome of post-operative hydrocephalic patients which is valuable to assist in counsel of their families.

NSP4 gene analysis of rotaviruses recovered from infected children with and without diarrhea

The transmembrane glycoprotein NSP4 functions as a viral enterotoxin capable of inducing diarrhea in young mice. It has been suggested that NSP4 may be a key determinant of rotavirus pathogenicity and a target for vaccine development. Twenty two G1P[6] rotaviruses from babies with and without diarrhea were comparatively analyzed along with reference strains and another 22 Taiwanese human rotaviruses of G and P combination types different from the G1P[6] type. The sequence variations in the NSP4 genes were studied by direct sequencing analysis of the amplicons of reverse transcription-PCR. Two genetic groups could be identified in this analysis. While the majority of these strains were closely related to the Wa strain, the G2 viruses were closely related to the S2 strain. Furthermore, phylogenetic analysis of the NSP4 gene among the G2 rotaviruses revealed three distinct lineages associated with DS-1, S2, and E210, respectively, as has been reported previously for the VP7 gene. However, we found no apparent correlation in the deduced amino acid sequences corresponding to the proposed enterotoxic peptide region between the rotaviruses recovered from individuals with and without diarrhea. The NSP4 gene product being a pathogenic determinant may not be a generalized phenomenon.

Enteric adenovirus infection in children in Taipei

Enteric adenoviruses (EAds), including type 40 (Ad40) and 41 (Ad41), can cause acute and severe diarrhea in young children. To delineate the epidemiological features of pediatric EAds infection in Taiwan, we conducted a retrospective study of all cases of EAds gastroenteritis in children treated at National Taiwan University Hospital for the period from July 1993 to December 1997. Stool samples were tested for the presence of Ad40 or Ad41 by enzyme immunoassay (EIA). A total of 64 cases of EAds infection in 63 children aged from 8 days to 81 months old with a median age of 9.5 months treated during the study period were identified. The male-to-female ratio was 1.63 (39/24). No obvious seasonal clustering of EAds cases was noted. Most patients (76.6%) were infected before the age of 2 years. Clinical features included diarrhea (96.9%), fever (54.7%), vomiting (45.3%), mild dehydration (43.8%), symptoms of upper respiratory tract infection (21.9%), and abdominal pain (12.5%). Analysis of fecal samples in patients with diarrhea showed watery diarrhea in 72.2%, diarrhea with mucus in 20%, diarrhea with blood in 3.1% and diarrhea with mucus and blood in 1.6 % of all patients. Nearly one-half (43.5%) of the patients had diarrhea for more than 7 days. Thirty-seven patients (57.8%) were hospitalized due to gastroenteritis or other unrelated diseases, and 11 patients (17.2%) acquired enteric adenovirus infection during hospitalization for other underlying disease. Twelve patients (18.8%) had mixed infections, which included rotavirus, respiratory syncytial virus (RSV) and Salmonella species. There were no deaths in this series. The findings of this study suggest that EAds are important etiologic microbes of pediatric gastroenteritis.

Rotavirus gastroenteritis in children: 5-year experience in a medical center

Rotavirus infection is the leading cause of childhood gastroenteritis. We retrospectively reviewed cases of rotavirus gastroenteritis at National Taiwan University Hospital from January 1993 to December 1997. During the study period there were 429 patients with rotavirus infection with ages ranging from 1 day to 16 years with a median of 13 months. The male-to-female ratio was 1.2:1. Infection occurred before the age of 2 years old in 76% of patients. The seasonal peak occurred in the late winter and early spring during 1993 to 1996, but the case number increased in late spring and summer in 1997. The G serotype of the rotavirus was identified in 302 patients (70%). Vomiting and dehydration developed more frequently following infection with G1 rotaviruses, while an increased frequency of seizures was noted following G2 infection; the differences were not statistically significant. One patient had two episodes of infection; the first one was caused by G1 rotavirus, and the strain causing the second infection could not be typed. In conclusion, the results suggest that there is a strong seasonal variation in the incidence and characteristics of rotavirus infection in Taipei area. The infections caused by G1 and G2 rotaviruses were clinically indistinguishable.

Quantitative competitive reverse transcription-PCR for quantification of dengue virus RNA

A quantitative competitive reverse transcription-PCR assay was developed to quantify dengue virus RNA in this study. The main features include a primer pair targeting a highly conserved region in the capsid and the addition of competing RNA that contains an internal deletion to provide a stringent internal control for quantification. It can be utilized to quantify RNA isolated from the four dengue virus serotypes but not RNA isolated from other flaviviruses, including Japanese encephalitis virus and hepatitis C virus, both prevalent in Asia. It can also be used to quantify dengue virus RNA isolated from the plasma of infected individuals. The sensitivity of the assay was estimated to be 10 to 50 copies of RNA per reaction, and twofold differences in virus titer are distinguishable. This assay is a convenient, sensitive, and accurate method for quantification and can be used to further understanding of the pathogenesis of dengue virus infection.

Reproductive and infectious risk factors for invasive cervical cancer in Taiwan

A community-based case-control study was carried out to assess multiple risk factors for invasive cervical cancer in Taiwan. All of 183 cases of pathologically confirmed cervical cancer cases and 293 healthy neighborhood controls were recruited from Taipei metropolitus. Healthy controls were matched with cervical cancer cases for age and residence. Multiple risk factors for cervical cancer were obtained from study subjects through standardized interviews according to a structured questionnaire. Serotiters of antibodies to Chlamydia trachomatis (CLT), human cytomegalovirus (HCMV) and human herpes simplex virus type 2 (HSV-2) were determined by enzyme-linked immunosorbent assay. Multiple logistic regression analysis were used to derive maximum likelihood estimates of multivariate-adjusted odds ratios (AOR) and confidence intervals (CI). After adjustment for potential risk factors, parity and number of vaginal delivery were associated with an increased risk of invasive cervical cancer. The higher the number of vaginal delivery, the higher the risk of developing cervical cancer (AOR = 6.2, 95% CI = 1.7-22.6 for 7 or more deliveries compared with 0-2 deliveries as the referent group). Increased cervical cancer risk was also significantly associated with the history of chronic cervicitis (AOR = 2.1, 95% CI = 1.1-3.8) and elevated serotiters of CLT (AOR = 7.0, 95% CI = 1.7-28.9), HCMV (AOR = 4.1, 95% CI = 1.5-11.3) and HSV-2 (AOR = 2.3, 95% CI = 1.1-4.6). The use of diaphragm for contraception was found to be associated with a decreased risk of cervical cancer (AOR = 0.4, 95% CI = 0.1-1.0).

Tuberculous pseudoaneurysm of the femoral artery: a case report

Pseudoaneurysm of the femoral artery is an extremely rare complication of tuberculosis. We present a case of tuberculous femoral pseudoaneurysm that was successfully treated with resection, direct anastomosis, and postoperative antituberculous chemotherapy.

Sequence analysis of VP1 and VP7 genes suggests occurrence of a reassortant of G2 rotavirus responsible for an epidemic of gastroenteritis

G2 rotavirus was prevalent in a 1993 epidemic of acute gastroenteritis in Taiwan. In this study, the genetic relationship among G2 rotavirus strains was analysed. The VP7 genes were amplified and sequenced. Except for one strain isolated in 1981, the nucleotide sequences of the VP7 genes of most of the G2 rotaviruses were very similar (identity > 97%) and were closely related to that of a Japanese G2 reference strain, S2. The genetic relatedness of G2 rotaviruses was analysed further by RNA-RNA hybridization. The genomes of the major G2 strains of 1993 did not hybridize well with those of the G2 strains of previous seasons in RNA segments 1, 6 and 7. Partial nucleotide sequences of the VP1 gene were analysed and appeared to be similar among the major G2 strains from the same epidemic (identity > 98%), whereas the identity of the VP1 genes of the major G2 strains of the 1993 epidemic to those of previous seasons was only about 84%. Since the numbers of mutations accumulated in the VP1 and VP7 genes over a period of 10 years were comparable, the significant change in the VP1 genes of the major strains of the 1993 epidemic suggests that these G2 rotaviruses had evolved by genetic reassortment.

Analysis of the steps involved in Dengue virus entry into host cells

The initial steps of dengue viral entry have been divided into adsorption and penetration using acid glycine treatment to inactivate extracellular virus after attachment to baby hamster kidney (BHK) cells but prior to penetration. First, we showed that virus infection was accomplished within 2 h after adsorption. Second, the assay was used to examine the properties of dengue envelope E protein-specific monoclonal antibodies (MAbs), lectins, and heparin. We found that three MAbs, 17-2, 46-9, and 51-3, may neutralize dengue 2 virus (DEN-2) through inhibition of not only viral attachment but also of penetration. However, one MAb, 56-3.1, interfered specifically with attachment. Therefore, the functional domains of E protein involved in attachment and penetration may be different. Moreover, studies with lectins indicated that carbohydrates, especially alpha-mannose residues, present on the virion glycoproteins may contribute to binding and penetration of the virus into BHK and mosquito C6/36 cells. Finally, virus infectivity was inhibited by heparin through its blocking effects at both virus attachment and penetration. This suggests that cell surface heparan sulfate functions in both viral attachment and penetration of DEN-2 virus. In conclusion, our results further elucidated some aspects of the dengue virus entry process.

Bilateral pathological femoral neck fractures secondary to ectopic parathyroid adenoma

A rare case of bilateral pathological femoral neck fractures secondary to ectopic parathyroid adenoma is reported. Both hip fractures were treated with closed reduction and internal fixation. The right hip fracture healed uneventfully, whereas the left hip fracture developed non-union that required subtrochanteric osteotomy and internal fixation and eventually healed. Neither hip developed avascular necrosis.

Enterovirus 71 from fatal and nonfatal cases of hand, foot and mouth disease epidemics in Malaysia, Japan and Taiwan in 1997-1998

Enterovirus 71 (EV71), one of the major causative agents for hand, foot and mouth disease (HFMD), is sometimes associated with severe central nervous system diseases. In 1997, in Malaysia and Japan, and in 1998 in Taiwan, there were HFMD epidemics involving sudden deaths among young children, and EV71 was isolated from the HFMD patients, including the fatal cases. The nucleotide sequences of each EV71 isolate were determined and compared by phylogenetical analysis. EV71 strains from previously reported epidemics belonged to genotype A-1, while those from recent epidemics could be divided into two genotypes, A-2 and B. In Malaysia, genotype A-2 was more prevalent, while in Japan and Taiwan, B genotype was more prevalent. Two isolates from fatal cases in Malaysia and one isolate from a fatal case in Japan were genotype A-2. However, all isolates from three fatal cases in Taiwan belonged to genotype B. The severity of the HFMD did not link directly to certain genotypes of EV71.

Study of Dengue virus infection in SCID mice engrafted with human K562 cells

Here we report that severe combined immunodeficient (SCID) mice engrafted with human K562 cells (K562-SCID mice) can be used as an animal model to study dengue virus (DEN) infection. After intratumor injection into K562 cell masses of PL046, a Taiwanese DEN-2 human isolate, the K562-SCID mice showed neurological signs of paralysis and died at approximately 2 weeks postinfection. In addition to being detected in the tumor masses, high virus titers were detected in the peripheral blood and the brain tissues, indicating that DEN had replicated in the infected K562-SCID mice. In contrast, the SCID mice were resistant to DEN infection and the mock-infected K562-SCID mice survived for over 3 months. These data illustrate that DEN infection contributed directly to the deaths of the infected K562-SCID mice. Other serotypes of DEN were also used to infect the K562-SCID mice, and the mortality rates of the infected mice varied with different challenge strains, suggesting the existence of diverse degrees of virulence among DENs. To determine whether a neutralizing antibody against DEN in vitro was also protective in vivo, the K562-SCID mice were challenged with DEN-2 and received antibody administration at the same time or 1 day earlier. Our results revealed that the antibody-treated mice exhibited a reduction in mortality and a delay of paralysis onset after DEN infection. In contrast to K562-SCID, the persistently DEN-infected K562 cells generated in vitro invariably failed to be implanted in the mice. It seems that in the early stage of implantation, a gamma interferon activated, nitric oxide-mediated anti-DEN effect might play a role in the innate immunity against DEN-infected cells. The system described herein offers an opportunity to explore DEN replication in vivo and to test various antiviral protocols in infected hosts.

Viral etiology of intussusception in Taiwanese childhood

BACKGROUND

Adenovirus infection and lymphoid hyperplasia have been associated with childhood intussusception. However, the extent of other viruses involved in this condition remains unclear. This prospective study investigates the relationship between some lymphotropic viruses and current childhood intussusception.

METHODS

Patients with intussusception encountered in a pediatric emergency department in a recent 3-year period were studied. Healthy infants and toddlers of comparable age served as controls. Throat and rectal viral cultures were performed in patients and controls. Viral antibodies against adenovirus, cytomegalovirus, human herpesvirus (HHV)-6, HHV-7 and Epstein-Barr virus (EBV) were tested in paired sera from the patients. Acute stage serum from each patient and mesenteric lymph nodes from patients requiring surgery were studied for the presence of adenovirus genome by PCR.

RESULTS

Twenty-seven of 61 (44.3%) intussusception patients, but only 2 of 52 (3.8%) healthy controls shed nonenteric adenovirus in throat and rectal specimens (P < 0.001). Of the 27 (74.1%) patients who shed adenovirus, 20 were older than 1 year old, whereas only 1 of 15 (6.7%) similarly aged patients in a previous study from the same area three decades ago did so (P = 0.001). Among 43 patients with available paired sera, acute primary viral infection was found in 17 (39.5%) by adenovirus, 4 (9.3%) by HHV-6, 5 (11.6%) by HHV-7, 2 (4.7%) by EBV and none by cytomegalovirus. Multiple viral infections occurred in 6 patients. Adenovirus genome was detected in 4 of 9 mesenteric lymph nodes and in only 3 of 60 (5%) acute phase sera.

CONCLUSIONS

Primary nonenteric adenovirus infection contributes to current childhood intussusception. Acute primary HHV-6, HHV-7 and EBV infections also play etiologic roles.

Thymic lymphoepithelioma-like carcinoma associated with thymoma in a patient with ocular myasthenia

A 65-year-old woman with ocular myasthenia was found to have three tumours in the anterior mediastinum, revealed by magnetic resonance imaging. All three lesions were radically resected. Histologically, one was a mixed-type thymoma, one a thymic lymphoepithelioma-like carcinoma, and the third had features of both these types. This appears to be the first reported case of coexisting thymic lymphoepithelioma-like carcinoma (TLC) and thymoma associated with ocular myasthenia.

Bronchial atresia associated with epibronchial right pulmonary artery and aberrant right middle lobe artery

We report a case of bronchial atresia associated with an epibronchial right pulmonary artery (ERPA) and an aberrant right middle lobe artery (ARMLA). CT showed a branching opacity, which was hyperintense on MR images, in the anterior segment of the right upper lobe with segmental hyperinflation and the ERPA. At surgery, the ARMLA was found to originate from the ERPA, crossing the anterior aspect of the right upper lobe bronchus. It is postulated that the ARMLA might have interfered with the normal bronchial development, leading to the development of segmental bronchial atresia.

Video-assisted thoracoscopic surgery for spontaneous hemopneumothorax

We operated on 403 patients with spontaneous pneumothorax between 1992 and 1996. Among these cases, 11 (2.7%) were spontaneous hemopneumothorax. The patients were all men, with ages ranging from 19 to 28 years (mean 23.8 years). The amount of blood drainage ranged from 650 to 2300 ml. Video-assisted thoracoscopic surgery was performed on these patients within 1 day after admission. The sources of bleeding were in the parietal and visceral pleurae of ruptured bullae (n = 6), the parietal pleura (n = 4), or the visceral pleura (n = 1). During operation, the ruptured bullae can be managed by an endoscopic linear stapler for a bullectomy, and the bleeding parietal pleura of the torn adhesion can be coagulated directly. Postoperative recovery of the 11 patients was uneventful, and they were discharged 4 to 10 days after the operation. No recurrence of spontaneous hemopneumothorax or any other complications occurred during follow-up. Thus spontaneous hemopneumothorax can be readily managed by cauterizing a bleeding site where appropriate, excising the apicocystic disease, and pleurodesis. As a minimally invasive method, video-assisted thoracoscopic surgery may be considered an initial treatment procedure in patients with spontaneous hemopneumothorax.

Identification of VP7 serotypes of human rotaviruses by enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction

Serotype specificity of human rotaviruses in Taiwan remained unclear. This study has established three methods for identification of G serotypes, fluorescent focus neutralization test (FFN), enzyme-linked immunosorbent assay by incorporating VP7 (G) serotype-specific monoclonal antibodies (ELISA-MAb) and reverse transcription-polymerase chain reaction (RT-PCR). FFN is a reference standard test for determination of G serotype. RT-PCR and ELISA-MAb were used for serotyping of rotavirus isolates and appeared to be accurate and more sensitive than FFN. Nevertheless, for serotyping the rotaviruses present in clinical stool samples, ELISA-MAb was not satisfactory, only 65.5% of the 264 specimens could be serotyped. The sensitivity of serotype prediction by RT-PCR was 89.4%. When both ELISA-MAb and RT-PCR were taken into account, G serotype could be predicted for 93.2% of the specimens. Serotyping results were comparable with the RNA profiles. Rotaviruses with similar RNA electrophoretic pattern had the same serotype specificity. RNA patterns could be used as a reference for prediction of serotypes. Because ELISA is easy to perform and less expensive, it would be suggested as a screening test. RT-PCR could be used for samples which could not be serotyped by ELISA-MAb. Furthermore, RT-PCR is especially valuable when serotype-specific monoclonal antibodies are not available.

Molecular cloning and expression of a fungal immunomodulatory protein, FIP-fve, from Flammulina velutipes

FIP-fve, a fungal immunomodulatory protein, was isolated from the fruiting bodies of the edible mushroom, Flammulina velutipes. FIP-fve was shown to stimulate blast-forming activity of human peripheral blood lymphocytes and gene expression of interleukin-2, interferon-gamma and tumor necrosis factor-alpha. Repeated administration of FIP-fve to mice inhibits the Arthur and systemic anaphylaxis reactions. FIP-fve cDNA was cloned and sequenced, and the amino acid sequence of FIP-fve deduced from the nucleotide sequence is identical to that previously determined by protein sequencing. FIP-fve cDNA was amplified by polymerase chain reaction, ligated into the expression vector, pGEX-2T, and expressed in Escherichia coli as a fusion protein of glutathione S-transferase (GST) and FIP-fve. The GST-FIP-fve fusion protein was soluble, and the yield of recombinant FIP-fve was about 5 mg/L of induced culture. The recombinant FIP-fve was obtained by cleaving the GST-FIP-fve fusion protein with thrombin and purifing to homogeneity. The recombinant FIP-fve had about 50% of the immunomodulatory activity of the native FIP-fve.

Transaortic patch angioplasty for left main coronary artery occlusion

Isolated total occlusion of the left main coronary artery is rare, and may be conventionally treated by standard bypass surgery. We describe a 54-year-old woman with isolated left main coronary artery disease presenting as unstable angina of 1 week's duration. She was treated with transaortic autologous pericardial patch angioplasty. Postoperative coronary angiography showed a widely patent left main coronary artery. She was angina-free 5 months postoperatively. In selected patients, this technique offers a valuable alternative to coronary artery bypass with the advantage of restoring more physiologic perfusion to the coronary tree.

Fip-vvo, a new fungal immunomodulatory protein isolated from Volvariella volvacea

A new fungal immunomodulatory protein (Fip) has been purified from the edible mushroom, Volvariella volvacea, and designated Fip-vvo. Analysis of the purified protein by SDS/PAGE followed by Coomassie Blue staining demonstrated that Fip-vvo is a single polypeptide with an apparent molecular mass of 15 kDa. Periodic acid/Schiff staining showed that this single polypeptide lacks carbohydrates. Using an in vitro bioassay measuring blast-formation stimulatory activity, Fip-vvo was shown to stimulate the maximum proliferation of human peripheral blood lymphocytes at a concentration of 5 microg/ml. Fip-vvo was capable of agglutinating rat red blood cells. Neither haemagglutination nor mitogenic activities were inhibited by mono- or dimeric sugars. In vivo, repeat administration of Fip-vvo greatly reduced the production of BSA-induced Arthus reaction in mice, whereas little effect was observed on the prevention of systemic anaphylaxis reactions. The selectively enhanced transcriptional expression of interleukin (IL)-2, IL-4, interferon-gamma, tumour necrosis factor-alpha, lymphotoxin and IL-2 receptor by Fip-vvo was also demonstrated by reverse transcriptase-PCR. This finding suggests that Fip-vvo exerts its immunomodulatory effects via cytokine regulation. In addition, the complete amino acid sequence of Fip-vvo was obtained by direct protein sequencing. This protein consists of 112 amino acid residues with a blocked N-terminal end and has a calculated molecular mass of 12667 Da not including the N-terminal blocking group. By gel filtration analysis, Fip-vvo exhibited a molecular mass of 26 kDa for the native molecules in PBS. This result indicates that native Fip-vvo is most likely a non-covalently associated homodimeric molecule.

Isolated common iliac artery occlusion secondary to atherosclerotic plaque rupture from blunt abdominal trauma: case report and review of the literature

Traumatic isolated common iliac artery occlusion is unusual. Only rare cases of common iliac arterial injuries resulting from blunt abdominal trauma have been reported, and most of them were attributed to the seat-belt syndrome and associated with visceral organ perforation or pelvic fracture. We reported an unusual isolated common iliac artery occlusion secondary to atherosclerotic plaque rupture from blunt abdominal compressive trauma without other visceral injury. This case presented with acute limb ischemia and paralysis that was successfully treated by thromboendarterectomy. The symptoms and signs, surgical modalities, and associated injuries were reported and the literature was also reviewed.

Seroepidemiology of Hantaan virus infection in Taiwan

In order to investigate the infection rate of Hantaan virus in Taiwan, a total of 6,536 human serum samples were collected from residents, selected by stratified random sampling, from 19 townships covering four different ethnic groups: Aborigines, Fukien Taiwanese, Hakka Taiwanese, and Mainland Chinese. Serum samples were screened for Hantaan virus antibodies by indirect immunofluorescence. The prototype Hantaan virus (76/118)-infected Vero E6 cells were used as the viral antigen for the antibody detection. Among 6,536 human serum samples, 403 (6.2%) samples had Hantaan virus antibodies. The seropositive rates for males and females were 6.1% and 6.2%, respectively. A higher seropositive rate was found among Aborigines on the Orchid Islets (11.5%) and Fukien Taiwanese on the Penghu Islets (11.6%), while the lowest rate was observed among Hakka Taiwanese in the south of Taiwan (2.5%). In comparing with different ethnic groups, the highest prevalence was found among Fukien Taiwanese (8.1%) and the lowest among Mainland Chinese (4.9%). Among the different geographical areas, the highest positive rate was found in western Taiwan (7.1%) and the lowest in southern Taiwan (5.4%). Hantaan virus antibodies were also detected in 22 of 548 (4.0%) rat serum samples. The highest seropositive rate was found in rat sera collected from the Orchid Islets (21.4%). None of the rat sera collected from Hsinchu, Miaoli, Changhua, Nantu, Yunlin, Chiayi, Tainan, and Penghu Counties were positive. Hantaan virus antibodies were found in rats: Rattus rattus (20%), Bandicota indica (9.0%), Rattus norvegicus (8.3%), Bandicota nemorivaga (6.3%), Rattus losea (4.2%), and Apodemus agrarius (1.6%). Hantaan virus antibodies were not detected in rat sera collected from species of Rattus coxinga, Rattus culturatus, Mus musculus, Mus caroli, Suncus murinus, and Apodemus semotus. The results show that the Hantaan or Hantaan-related virus exists and is distributed widely in both human and rats in Taiwan.

Study of young women vaccinated against rubella virus for 10 years in Taiwan

Since the licensing of the rubella virus vaccine (RA 27/3 strain) in 1979, clinical studies on the RA 27/3 strain vaccine, which gives rise to high titer antibody, have been reported. In the present study, this vaccine was used to examine the immune response in young women. Volunteers without the previous immunity to rubella virus screened by hemagglutination inhibition (HAI), latex agglutination (LA), fluorescence immunoassay (FIA) and solid-phase immunoassay (SPIA) tests were injected with Rudivax vaccine or Meruvax II vaccine. Adverse reactions occurred between 10 and 20 days after vaccination in 30% of the volunteers. After 28-35 days, vaccinees developed antibodies against rubella virus. The titer of rubella antibody reached it's peak from the 40th day through the 100th day. One year after vaccination, the geometric mean titer (GMT) of rubella virus antibody still remained over 1 : 64 (HAI) and 1 : 38.2 (FIA), and SPIA IgG RI mean was 2.80. Two years later, the antibody titers were 1 : 52 by HAI and 1 : 32.1 by FIA, and SPIA IgG RI mean was 2.75. After 5 years, the antibody titers were 1 : 48.6 (HAI) and 1 : 28.2 (FIA), and SPIA IgG RI mean was 2.74. After 10 years, the anti-rubella virus antibody titers were 1 : 38.9 (HAI) and 1 : 25.1 (FIA), and SPIA IgG RI mean was 2.42. LA antibody still remained seropositive. In conclusion, the rubella vaccine RA 27/3 is safe and efficient, and it is applicable for the control of the rubella in Taiwan.

Prolonged circulatory arrest in moderate hypothermia with retrograde cerebral perfusion. Is brain ischemic?

BACKGROUND

Circulatory arrest (CA), which provides a bloodless field and good visualization without the need of aortic cross-clamp, is commonly used to facilitate repair of aortic lesions. However, extended periods of CA may impair cerebral metabolism and cause ischemic injury. Studies were performed to evaluate the efficacy of retrograde cerebral perfusion (RCP) in protecting the brain from ischemic injury during a prolonged period of CA in moderate hypothermia.

METHODS AND RESULTS

Twenty-three patients (18 men and 5 women) were operated on for aortic lesions (17 acute type A aortic dissection and 6 chronic type A aortic dissection with Marfan's syndrome). The aortic operations were performed with CA (58 to 104 minutes; mean +/- SD, 75 +/- 12 minutes) at a rectal temperature of 23.3 +/- 0.5 degrees C (21 degrees C to 25 degrees C). For RCP, cold (14 degrees C to 18 degrees C) oxygenated blood (300 mL/min) was pumped to the superior vena cava with internal jugular venous pressure of 15 +/- 5 mm Hg. The cardiopulmonary bypass time was 157 +/- 18 minutes. Cortical blood flow during RCP detected by subdural laser Doppler probe was 10 +/- 5% of baseline. Percent oxygen extraction and pyruvate and lactate levels (26 +/- 2% and 0.43 +/- 0.17 and 45 +/- 16 mg/dI) were insignificantly different from those before CA (28 +/- 3% and 0.71 +/- 0.08 and 62 +/- 20 mg/dL, P > .05). Creatine kinase-BB isoenzyme was undetectable. All but 1 patient survived the operation (95.5%) and woke up without neurological deficit. Follow-up (mean, 13 months) was complete in all survivors. There were no late deaths. Cerebral functional studies performed 3 months after discharge showed results insignificantly different from those of the normal control subjects.

CONCLUSIONS

There is no evidence of ischemia of the brain during prolonged moderate hypothermic CA with the aid of RCP. Retrograde cerebral perfusion effectively extends the safe time of CA. Deep hypothermia during CA seems unnecessary.