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C L Kao

Publications and source records attributed to C L Kao.

At least 37 records · Page 2Linked to original sources
PubMed1999

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.

Adsorption↗
PubMed1999

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.

Aged↗
PubMed1999

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.

Amino Acid Sequence↗
PubMed1999

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.

DNA Primers↗
PubMed1998

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.

Adult↗
PubMed1998

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.

Adenoma↗
PubMed1998

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.

Aged↗
PubMed1998

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.

Acute-Phase Reaction↗
PubMed1998

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.

Animals↗
PubMed1998

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.

Abnormalities, Multiple↗
PubMed1997

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.

Adjuvants, Immunologic↗
PubMed1997

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.

Arterial Occlusive Diseases↗
PubMed1997

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.

Angioplasty↗
PubMed1997

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.

Animals↗
PubMed1996

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.

Adult↗
PubMed1996

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.

Adolescent↗
PubMed1996

Unruptured sinus of Valsalva aneurysm with right ventricular outflow tract obstruction associated with ventricular septal defect.

We describe an aneurysm originating from the right sinus of Valsalva, with right ventricular outflow tract obstruction associated with ventricular septal defect, in a 9-year-old boy. Diagnosis was made by echocardiography and cardiac catheterization. Successful surgical repair of ventricular septal defect and aortic valvuloplasty resulted in symptomatic improvement.

Aortic Aneurysm↗