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J K Wang

Publications and source records attributed to J K Wang.

At least 19 recordsLinked to original sources
PubMed2006

QTL analysis for rice grain length and fine mapping of an identified QTL with stable and major effects.

Grain length in rice plays an important role in determining rice appearance, milling, cooking and eating quality. In this study, the genetic basis of grain length was dissected into six main-effect quantitative trait loci (QTLs) and twelve pairs of epistatic QTLs. The stability of these QTLs was evaluated in four environments using an F7 recombinant inbred line (RIL) population derived from the cross between a Japonica variety, Asominori, and an Indica variety, IR24. Moreover, chromosome segment substitution lines (CSSLs) harboring each of the six main-effect QTLs were used to evaluate gene action of QTLs across eight environments. A major QTL denoted as qGL-3a, was found to express stably not only in the isogenic background of Asominori but also in the recombinant background of Asominori and IR24 under multiple environments. The IR24 allele at qGL-3a has a positive effect on grain length. Based on the test of advanced backcross progenies, qGL-3a was dissected as a single Mendelian factor, i.e., long rice grain was controlled by a recessive gene gl-3. High-resolution genetic and physical maps were further constructed for fine mapping gl-3 by using 11 simple sequence repeat (SSR) markers designed using sequence information from seven BAC/PAC clones and a BC4F2 population consisting of 2,068 individuals. Consequently, the gl-3 gene was narrowed down to a candidate genomic region of 87.5 kb long defined by SSR markers RMw357 and RMw353 on chromosome 3, which provides a basis for map-based cloning of this gene and for marker-aided QTL pyramiding in rice quality breeding.

Alleles↗
PubMed2006

Single-center experience of pediatric heart transplantation in taiwan.

Heart transplantation (HTx) is a treatment for end-stage heart failure or a complex or inoperable congenital defect. The long-term survival and the adequate donor to recipient body weight (D/R BW) ratio remain to be determined. From March 1995 to May 2004, 14 children (6 months-16 years of age) underwent HTx due to underlying diseases of idiopathic dilated cardiomyopathy (n = 10; 71.4%), congenital heart disease (n = 3; 21.4%), and Kawasaki disease (n = 1; 7.1%). Donor-recipient body weight ratio ranged from 0.89 to 3.9. Big heart syndrome was present in one patient when D/R BW ratio was more than 3. Actuarial survival was 92.9% at 5 years after transplantation. Only the one patient who had Kawasaki disease died due to early primary graft failure. HTx is a feasible method with good long-term survival rates for end-stage heart failure or for complex or inoperable congenital defects. After careful pretransplant evaluation, a high D/R BW ratio (more than 3) is acceptable.

Body Weight↗
PubMed2006

Safrole-induced Ca2+ mobilization and cytotoxicity in human PC3 prostate cancer cells.

The effect of the carcinogen safrole on intracellular Ca2+ mobilization and on viability of human PC3 prostate cancer cells was examined. Cytosolic free Ca2+ levels ([Ca2+]i) were measured by using fura-2 as a probe. Safrole at concentrations above 10 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 350 microM. The Ca2+ signal was reduced by more than half after removing extracellular Ca2+ but was unaffected by nifedipine, nicardipine, nimodipine, diltiazem, or verapamil. In Ca2+-free medium, after treatment with 650 microM safrole, 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) failed to release Ca2+. Neither inhibition of phospholipase C with U73122 nor modulation of protein kinase C activity affected safrole-induced Ca2+ release. Overnight incubation with 0.65-65 microM safrole did not affect cell viability, but incubation with 325-625 microM safrole decreased viability. Collectively, the data suggest that in PC3 cells, safrole induced a [Ca2+]i increase by causing Ca2+ release from the endoplasmic reticulum in a phospholipase C- and protein kinase C-independent fashion, and by inducing Ca2+ influx. Safrole can decrease cell viability in a concentration-dependent manner.

Calcium Channel Blockers↗
PubMed2006

Recurrent pneumothorax in pregnancy: what should we do after placing an intercostal drain.

Recurrent pneumothorax is rare during pregnancy. We describe a Chinese woman, with a history of spontaneous pneumothorax managed with an intercostal drain, who developed a recurrent pneumothorax during her 32nd week of pregnancy. There is no consensus on management in this situation. We review the literature and discuss different management approaches. Thirty-six cases of antepartum pneumothorax have been reported in 31 case reports. An intercostal drain only (n=11) or surgeries (thoracotomy, n=9; or video-assisted thoracoscopy, n=2) were common treatment options with no surgical complications reported. Twenty-two (61%) patients progressed to a normal vaginal delivery, while the rest required forceps delivery (22%) or Caesarean section (14%). No single treatment option outweighed the others. There were no maternal or foetal complications reported in those who underwent antepartum surgical intervention. Surgical management of recurrent pneumothorax during pregnancy is well tolerated.

Adult↗
PubMed2002

Clinical features of atypical Kawasaki disease.

From 1989 through 1998, a total of 132 children admitted to the National Taiwan University Hospital were identified as having Kawasaki disease. Twenty (15%) of them did not meet the diagnostic criteria of Kawasaki disease, but were considered atypical Kawasaki based on the specific clinical signs and exclusion of other causes by serologic study and culture result. The patients' age ranged from 5 months to 11 years, with a mean of 22.2 months and a median of 15 months. The male to female ratio was 1.9:1. Twenty-five percent (5/20) of them had coronary arterial lesion. No difference was found in the age distribution, sex, and rate of coronary artery involvement between typical and atypical Kawasaki disease. All patients were treated with intravenous immunoglobulin and aspirin except for 2 patients. At follow-up, patients with coronary arterial lesions had a prognosis as good as those with typical Kawasaki disease. According to these observations, atypical Kawasaki disease may be part of Kawasaki disease occurring via the same pathogenesis, but has incomplete manifestation. Clinical practitioners should have a high index of suspicion to diagnose and initiate prompt treatment to reduce the comorbidity of coronary arterial disease in patients with atypical Kawasaki disease.

Child↗
PubMed2001

Validation of pulmonary venous obstruction by electron beam computed tomography in children with congenital heart disease.

The purpose of this study was to explore the useful imaging findings of electron beam computed tomography (EBCT) for diagnosing pulmonary venous obstruction (PVO) in children with congenital heart disease. From July 1995 to March 1998, 17 children (9 girls and 8 boys, aged 7 days to 14 years and 9 months [median 3 months]) with the diagnosis of PVO were enrolled in this study. All images were obtained by EBCT at the end-diastolic phase of the cardiac cycle after administration of intravenous iodinated contrast medium. The findings of 25 EBCT studies were retrospectively analyzed by 2 radiologists and were correlated with echocardiography, angiocardiography, and surgical findings. Main findings on EBCT for PVO were (1) structural narrowing, (2) thickened interlobular septa, (3) peribronchovascular cuffing, and (4) ground-glass opacity of the alveoli. Structural narrowing along the course of the pulmonary venous drainage was the most important finding in all examinations (25 of 25). Lung parenchymal changes secondary to PVO included thickened interlobular septa (17 of 25), peribronchovascular cuffing (15 of 25), and ground-glass opacity of the alveoli (8 of 25). Thus, the combination of these findings provides very useful data for the definitive diagnosis of PVO. Characteristic electron beam computed tomographic findings can validate suspected PVO noninvasively.

Adolescent↗
PubMed2001

Balloon angioplasty for obstructed modified systemic-pulmonary artery shunts and pulmonary artery stenoses.

OBJECTIVES: The results of percutaneous balloon angioplasty for obstructed modified Blalock-Taussig (BT) or central shunts and pulmonary artery (PA) stenoses were studied to assess its role as an alternative to second shunt and surgical PA angioplasty. BACKGROUND: Obstruction of a modified shunt and PA stenosis related to the shunt or ductus are not infrequent. A second shunt with or without PA angioplastv is required if the PA size, morphology or age of the patient is suboptimal for definitive surgery. METHODS: From June 1994 to May 1999, balloon angioplasty for obstructed systemic-to-PA shunts was performed in 46 patients, with ages ranging from 1 month to 7.4 years (2.2 +/- 1.9 years). Among the 46 patients, 32 had modified BT shunts, 5 had bilateral shunts, 7 had modified central shunts, and 2 had both modified BT and central shunts. Stenoses were seen in 27 main branch PAs, and interruption was present in three. A concurrent balloon angioplasty was attempted in 28 main branch PAs, but it was performed in only 25 vessels. RESULTS: Balloon dilation for obstructed modified shunts was considered to be effective in 42 patients (91%), while angioplasty for PA stenosis was effective in 14 vessels and not effective in 11 vessels. After balloon dilation angioplastv, oxygen saturation in the aorta increased from 74.4 +/- 4.3% to 80.8 +/- 3.6% (p < 0.01) in these 46 patients. One patient died of pneumonia. Eight patients required an additional modified BT shunt soon after the procedure because of severe stenosis or interruption at main branch PA. After a mean follow-up period of 11.6 +/- 5.4 months, 29 patients underwent a repeated imaging study to evaluate the morphology and size of the PAs. Of these 29 patients, 26 underwent open-heart surgery, with two mortalities. CONCLUSIONS: When a second shunt is under consideration because of obstruction of the modified shunt, balloon angioplasty is a possible alternative procedure. Pulmonary artery stenosis, if present, can be simultaneously dilated.

Angioplasty, Balloon↗
PubMed2001

Retroesophageal aortic arch: diagnostic and therapeutic implications of a rare vascular ring.

Retroesophageal aortic arch (REAA) can be further divided to right or left retroesophageal aortic arch. The right REAA has right ascending and left descending aorta with retroesophageal segment, whereas the left REAA has left ascending and right descending aorta. The REAA with retroesophageal segment may cause tracheoesophageal compression by the formation of a vascular ring. A total of eight patients were identified from the database from 1996 to 1999. Among them, five were right REAA and three were left REAA. The age at diagnosis varied from 4 days to 16 years (median 8 years). The clinical findings and initial diagnostic investigations, including the chest X-ray, echocardiography and esophagogram, suspected the presence of this anomaly. The diagnosis can be confirmed by ultrafast computed tomography with or without three-dimensional reconstruction. Half of the total patients, two of right and two of left REAA were symptomatic and needed operation. The symptoms related to the retroesophageal aortic arch appeared during infancy and early childhood (six cases), and only rarely in late childhood and adults (two cases). Half of the patients were associated with congenital heart disease, but no specific patterns of congenital heart disease were identified. The sensitivity of the early diagnosis of REAA by chest roentgenogram, echocardiography, esophagogram and angiography was 37% (3/8), 0% (0/7), 100% (1/1) and 60% (3/5), respectively. The sensitivity of ultrafast CT was 100% (8) in delineating both retroesophageal segment and complete vascular ring. Operation to relieve the vascular compression was performed in two cases with right REAA and two with left REAA. Only one died after the operation, due to pulmonary arterial sling and tracheal stenosis. The surviving patients had been asymptomatic during follow up. In conclusion, REAA can be best diagnosed by ultrafast computed tomography with or without three-dimensional reconstruction. If symptomatic, surgery to relieve the compression is effective and safe.

Adolescent↗
PubMed2001

Cardiac rhythm disturbances in patients with left atrial isomerism.

This long-term study sought to determine the clinical implication of defective sinus node and AV conduction tissue in patients with left atrial isomerism (LAI). From 1984 to 1998, a total of 22 patients were identified as LAI. Patient age at the last follow-up ranged from 2 to 276 months (90+/-70 months). Associated cardiac anomalies were interruption of the inferior vena cava (n = 18, 82%), common atrium (n = 9, 41%), AV canal (n = 14, 64%), double-outlet right ventricle (n = 8, 36%), and pulmonary stenosis (n = 15, 68%). Palliative interventions were performed in 16 patients (Fontan-type operation in 4 patients, shunt followed by Fontan-type operation in 2, repair of septal defect in 4, and extracardiac intervention in 6). During the follow-up, over half of the patients (n = 14, 64%) developed bradyarrhythmia (onset age: from 1 to 264 months; median 78 months): junctional rhythm (n = 11), sinus bradycardia (n = 8) (5 patients also had junctional rhythm), and AV block (n = 2, both also had junctional rhythm). The probability free from bradyarrhythmia was 80% and 46% at the age of 2 and 6 years, respectively. None of the bradyarrhythmias were directly related to open-heart surgery. Besides, junctional ectopic tachycardia occurred after Fontan-type operation in three of six patients. In two patients, a Mahaim-like pathway was identified during the electrophysiological study. The patients with LAI had a high probability of developing bradyarrhythmias due to abnormal sinus node function. Varied AV conduction abnormalities may include compromised AV conduction, junctional ectopic tachycardia after Fontan-type operation, and an association of Mahaim-like pathway.

Adolescent↗
PubMed2001

Neurotrophin-3 mediates the autocrine survival of the catecholaminergic CAD CNS neuronal cell line.

The mechanisms for neuronal survival in the CNS are not well understood, but are likely to be complex due to possible autocrine and redundant neurotrophic support. Most studies have focused on the nerve growth factor (NGF)/TrkA pathway in peripheral neurons, and little is known regarding the other neurotrophins, particularly neurotrophin-3 (NT3)/TrkC. Progress has also been hampered by the paucity of homogenous and accessible CNS neuronal experimental models. We now report that the novel catecholaminergic CNS cell line, CAD, is capable of autocrine survival mediated by NT3. The CAD cell is of CNS neuronal origin and can survive and morphologically differentiate in the absence of exogenously provided trophic factors. However, neutralizing reagents against NT3 (the neutralizing TrkC-IgG fusion protein and anti-NT3 antibodies), but not those that block the other neurotrophins, inhibited survival of differentiating CAD cells. Moreover, Trk phosphorylation was detected in CAD cells and its inhibition by K252a was correlated with K252a-induced apoptosis. Finally, endogenous NT3 was detectable in CAD cell extracts by a specific ELISA assay. Thus, CAD cells possess an autocrine survival capability mediated by NT3, and may provide a valuable model system for studying the signaling pathways that mediate the actions of this little understood neurotrophin.

Animals↗
PubMed2001

Heart transplantation and the Batista operation for children with refractory heart failure.

Medically refractory heart failure may be present in children with cardiomyopathy (CMP) or complex congenital heart disease (CHD). In adults, the surgical management of this condition is either heart transplantation or the Batista operation. From March 1995 to January 2000, a total of 6 children, aged from 1 to 16 years, with medically refractory heart failure associated with CMP or complex CHD underwent cardiac transplantation and one of them also had the Batista operation as a bridge to transplantation. One of the 6 patients died of intractable sepsis 17 days after the operation, but the other 5 were discharged with satisfactory hemodynamics. Immunosuppressive agents, including azathioprine, cyclosporin or FK-506, were given. One patient experienced moderate acute rejection, but it was controlled by FK-506, OKT-3 and solumedrol. However, another suffered from lymphoproliferative disease 8 months after transplant, but it was controlled by intravenous immunoglubulin, alpha-interferon and acyclovir. Cardiac function during serial follow-up (range, 1 month to 5 years) revealed normal systolic and diastolic function and none received any anticongestive medications. Almost all patients received an oversized donor heart. The left ventricle (LV) mass was remodeled, initially as an decrease and later as an increase. The patient who underwent the Batista operation was discharged 1 month after the operation with an increased LV ejection fraction (from 10% to 22%). She was successfully bridged to heart transplantation 7 months after the Batista operation. The results of cardiac transplantation in growing children are satisfactory and remain the mainstay of surgical treatment for medically refractory heart failure in these patients. However, with a shortage of donor hearts, the Batista operation may be adopted as a bridge to heart transplant with a fair response.

Adolescent↗
PubMed2001

Preoperative diagnosis by electron beam computed tomography and perioperative management of primary tracheal anomalies in tetralogy of Fallot.

PURPOSE: To investigate the usefulness of electron beam computed tomography (EBCT) in the preoperative detection and perioperative management of insidious concomitant primary tracheobronchial anomalies in patients with tetralogy of Fallot (TF). METHODS: From July 1995 to October 1999, 88 children (38 girls, 50 boys) with TF were enrolled in this study. EBCT examinations provided information needed to plan management. The final diagnoses of airway abnormalities were correlated with the findings of bronchoscopy in five patients and confirmed during surgery. RESULTS: Fourteen (16%) of the 88 patients had associated primary tracheobronchial anomalies. Nine patients had tracheal bronchi, which were combined with tracheobronchial stenosis in two patients and with tracheal stenosis in one patient. Two patients had tracheal diverticulum, which was combined with lower tracheal stenosis in one patient. Two patients had congenital tracheal stenosis. Tracheomalasia was found in one patient. Three patients with ventilation difficulties died postoperatively. Special attention was given to the care of the diseased airways perioperatively, and the remaining 11 patients had a smooth course of hospitalization and discharge. CONCLUSIONS: Our results show that EBCT provides good delineation of both cardiac and tracheobronchial anomalies and suggest that it should be used perioperatively to detect associated airway anomalies in TF, to facilitate the design of an appropriate ventilation care strategy.

Adolescent↗
PubMed2001

Combined atrial and arterial switch operations for congenitally corrected transposition.

Conventional repair of congenitally corrected transposition of the great arteries (CCTGA) is directed at eliminating the associated defects and leaves the right ventricle in a systemic position. The long-term outcome of this procedure may involve deterioration of right ventricular function with tricuspid regurgitation and failure of the conduction system. We describe two consecutive patients with CCTGA, one of whom had apicocaval juxtaposition. The patients were aged 19 and 16 months, respectively, and both underwent a combination of atrial and arterial switch. These are the first two reported cases of successful completion of this type of operation in Taiwan. Our review of previously reported cases suggested that no significant difference exists in the outcome of patients with this condition who undergo either arterial switch or Rastelli-type repair plus atrial redirection. However, reported patients who underwent anatomic repair had lower early mortality, late mortality, and incidence of complete heart block than those who underwent conventional repair. The present two cases and our review of the literature suggest that, among patients with apicocaval juxtaposition, 1) Mustard operation is optimal for patients with small atrial volume; 2) one-and-one-half ventricular repair may be helpful to the outcome, especially when treatment is combined with Rastelli-type repair; and 3) excellent access to the ventricular septal defect through the tricuspid valve is afforded via a left atriotomy. From the present two cases and our review of the literature, we conclude that anatomic repair is superior to conventional repair of CCTGA in terms of protection against dysfunction and failure of the anatomic right ventricle, tricuspid valve, and conduction system. Long-term follow-up is mandatory.

Cardiac Surgical Procedures↗
PubMed2001

Modified arterial switch operation by sharing the common wall between the great arteries.

BACKGROUND: Suprapulmonary stenosis and coronary arterial obstruction still remain as problems after an arterial switch operation (ASO). We used a modified ASO applying the common wall and in situ transfer techniques to improve the current procedure. METHODS: From October 1996 to December 1997, 11 babies aged 6 days to 3 months with transposition of the great arteries underwent a modified ASO which included sharing the common wall between the great arteries until above the anterior neoaortic suture-line for coronary and pulmonary artery reconstruction. Coronary arteries were of usual type in three cases, juxtacommissural origin in five, and a high takeoff in one; all were redirected almost in situ. RESULTS: There was no early death (< 30 d), coronary or bleeding problems. One late death occurred after a repeat surgery for suprapulmonary stenosis. This was caused by upward stretching of the left pulmonary artery, which was placed above the high left-sided neoaortic anastomosis for in situ transfer of the high takeoff coronary arteries. Intraluminal growth of the adventitia also contributed to suprapulmonary stenosis, which decreased significantly when the common wall adventitia was cleaned in the last two cases we operated on. Ten patients were doing well at follow-up (30.9 +/- 5.2 mo). CONCLUSIONS: This modified ASO by common wall and in situ transfer might avoid coronary kinking and lessen the chance of postoperative bleeding. To avoid suprapulmonary stenosis, common wall adventitia inside the pulmonary pathway should be cleaned, and the left and right pulmonary arteries should also be kept in situ as possible as in coronary redirection.

Humans↗
PubMed2001

Valveless outflow reconstruction using autologous tissue as a posterior wall for pulmonary atresia with ventricular septal defect.

BACKGROUND AND PURPOSE: Reoperation is inevitable for some patients with pulmonary atresia who receive a heterograft or homograft in a primary Rastelli operation. Nonetheless, the need for reoperation in patients with classic Fallot's tetralogy who have undergone total correction with a transannular patch is unusual. We sought to change pulmonary atresia into Fallot's tetralogy and used a transannular patch instead of the conventional Rastelli operation. PATIENTS AND METHODS: Valveless outflow direct reconstruction was performed on 10 consecutive patients with pulmonary atresia and ventricular septal defect between August 1997 and 1999. Patient ages ranged from 1.3 to 11.5 years. A Blalock-Taussig shunt was previously constructed in four of these patients and a central shunt was constructed in five. The major aortopulmonary collateral arteries were occluded in one patient by repeated coil embolization after the central shunt. The strategy was to connect the right ventriculotomy with the pulmonary arteries directly, even if there was a gap with a long atretic cord. In patients with a previous central shunt covered with a Gore-Tex membrane, the reactive visceral pericardium over the in situ tissue (the left atrium, right ventricle, or aorta) was used as the autologous posterior wall. Thus, only autologous, fresh pericardium without a valve was used to cover the anterior part of the right ventricular outflow tract, as in the repair of classic Fallot's tetralogy with a transannular patch. RESULTS: There was no mortality, and the postoperative central venous pressure was low in all patients. No gradient was noted across the right ventricular outflow tract. Follow-up echocardiography revealed a competent tricuspid valve with mild pulmonary regurgitation in all patients. CONCLUSIONS: The results of this study suggest that valveless outflow direct reconstruction provides adequate pulmonary circulation without hypertension in pulmonary atresia patients with a ventricular septal defect if the tricuspid valve is competent.

Child, Preschool↗
PubMed2001

Echocardiographic assessment of total anomalous pulmonary venous connections in pediatric patients.

BACKGROUND AND PURPOSE: Cardiac catheterization can be superfluous and risky for sick babies, infants, and young children with total anomalous pulmonary venous connection (TAPVC). This study assessed the accuracy of echocardiography in the clinical assessment of pediatric patients with TAPVC before cardiac surgery. PATIENTS AND METHODS: A total of 15 consecutive patients with TAPVC treated between July 1, 1993, and December 31, 1999, were included in this retrospective study. Patients with TAPVC with heterotaxy syndrome were excluded. We assessed this cardiac anomaly preoperatively using plain chest roentgenograms, echocardiography, and magnetic resonance imaging. A combination of suprasternal, parasternal, subcostal, and apical four-chamber views and their tilting scans were employed for diagnosis and to trace the course of the anomalous pulmonary venous connection. RESULTS: Interatrial right-to-left shunt via atrial septal defects were documented by two-dimensional echocardiography with color Doppler mapping in all 15 patients. Patent ductus arteriosus was found in six patients. Cardiomegaly with enlargement of the right atrium and the right ventricle could be seen on plain chest roentgenograms and by echocardiography in all but two patients with infracardiac TAPVC. In all patients, the left innominate vein, coronary sinus or right atrium, and portal vein were the draining sites of supracardiac, cardiac, and infracardiac TAPVC, respectively. A pattern of continuous flow without phasic variation, which is suggestive of stenosis of the pulmonary vein, was found in two patients with infracardiac TAPVC with obstruction. The surgical findings were reviewed and correlated well with those of the echocardiography. CONCLUSIONS: In infants and children with TAPVC, the drainage sites and flow profiles of the pulmonary veins can be exactly determined by Doppler echocardiography preoperatively, which makes cardiac catheterization and angiocardiography unnecessary.

Child↗
PubMed2001

[Contents of ten trace elements in Epimedium acuminatum Franch. and its different processed products].

OBJECTIVE: Determine and compare the contents of ten trace elements in crude E. acuminatum and its three different processed products. METHOD: Using flame atomic absorption spectrometry. RESULT: The ten trace elements were found in both the crude drug and its three processed products, and in terms of contents some of the trace elements in all the three processed products are higher than those in the crude drug. CONCLUSION: According to the trace element contents, the three processed products of E. acuminatum have their own advantages. It is thus suggested that thoroughgoing clinical and experimental researches be performed anew for the long-shelved processing methods.

Epimedium↗