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C J Wu

Publications and source records attributed to C J Wu.

At least 55 records · Page 3Linked to original sources
PubMed1999

Rapid induction of cytokine gene expression in the lung after single and fractionated doses of radiation.

PURPOSE: To investigate cytokine gene expression in the lung after single and fractionated doses of radiation, and to investigate the effect of steroids and the genetic background. MATERIALS AND METHODS: Expression of cytokine genes (mTNF-alpha, mIL-1alpha, mIL-1beta, mIL-2, mIL-3, mIL-4, mIL-5, mIL-6, mIFN-gamma) in the lungs of C3H/HeJ and C57BL/6J mice was measured by RNase protection assay at different times after various doses of radiation. The effects of dexamethasone and fractionated radiation treatment on gene expression were also studied. RESULTS: IL-1beta was the major cytokine induced in the lungs of C3H/HeJ mice within the first day after thoracic irradiation. Radiation doses as low as 1 Gy were effective. Responses to 20 Gy irradiation peaked within 4-8h and subsided by 24 h. With the exception of IL-1alpha and TNF-alpha, the other cytokines that were investigated had undetectable pre-treatment mRNA levels and were not radiation inducible. Similar responses were seen in C57BL/6J mice, although TNF-alpha was induced and there were some quantitative differences. Pre-treatment of C3H/HeJ mice with dexamethasone reduced basal and induced IL-1 levels, but complete inhibition was not achieved. Dexamethasone was also effective if given immediately after irradiation. Fractionated daily doses of radiation (4 Gy/day) helped to maintain cytokine gene expression for a longer period. CONCLUSIONS: Inflammatory genes are rapidly induced in the lung by irradiation. This response cannot be readily abolished by steroid pre-treatment. Fractionated treatment schedules help to perpetuate the response.

Animals↗
PubMed1999

Sustained mitogen-activated protein kinase activation is induced by transforming erbB receptor complexes.

We used a genetic approach to characterize features of mitogen-activated protein kinase (MAPK) activation occurring as a consequence of expression of distinct erbB receptor combinations in transformed human cells. Kinase-deficient erbB proteins reduced epidermal growth factor (EGF)-induced tyrosine phosphorylation of endogenous Shc proteins and also reduced immediate and sustained EGF-induced ERK MAPK activities in human glioblastoma cells, although basal ERK MAPK activities were unaffected. Basal and EGF-induced JNK and p38 MAPK kinase activities were equivalent in parental cancer cells and EGFR-inhibited subclones. When ectopically overexpressed in murine fibroblasts and human glioblastoma cells, a constitutively activated human EGF receptor oncoprotein (deltaEGFR) induced EGF-independent elevation of basal ERK MAPK activity. Basal JNK MAPK kinase activity was also specifically induced by deltaEGFR, which correlated with increased phosphorylation of a 54-kDa JNK2 protein observed in deltaEGFR-containing cells. The JNK activities in response to DNA damage were comparably increased in cells containing wildtype EGFR or deltaEGFR. Consistent with the notion that transforming erbB complexes induce sustained and unregulated MAPK activities, coexpression of p185(neu) and EGFR proteins to levels sufficient to transform murine fibroblasts also resulted in prolonged EGF-induced ERK in vitro kinase activation. Transforming erbB complexes, including EGFR homodimers, deltaEGFR homodimers, and p185(neu)/EGFR heterodimers, appear to induce sustained, unattenuated activation of MAPK activities that may contribute to increased transformation and resistance to apoptosis in primary human glioblastoma cells.

Adaptor Proteins, Signal Transducing↗
PubMed1999

Increasing the thermostability of D-xylose isomerase by introduction of a proline into the turn of a random coil.

Thermostability can be increased by introducing prolines at suitable sites in target proteins. Two single (G138P, G247D) mutants and one double (G138P/G247D) mutant of xylose isomerase from Streptomyces diastaticus No.7, strain M1033 have been constructed by site-directed mutagenesis. With respect to the wild-type enzyme, G138P showed about a 100% increase in thermostability, and G247D showed an increased catalytic activity. Significantly, the double mutant, G138P/G247D displayed even higher activity than G247D and better heat stability than G138P. Its half life was about 2.5-fold greater than the wild-type enzyme, using xylose as a substrate. Molecular modelling suggested that the introduction of a proline residue in the turn of a random coil may cause the surrounding conformation to be tightened by reducing the backbone flexibility. The change in thermostability can, therefore, be explained based on changes in the molecular rigidity. Furthermore, the improvements in the properties of the double mutant indicated that the advantages of two single mutants can be combined effectively.

Aldose-Ketose Isomerases↗
PubMed1999

Short stature in a 46,XX male adolescent.

We describe a patient with a 46,XX karyotype who was assessed because of short stature and a subnormal rate of linear growth. The patient had normal male external genitalia. Endocrinologic analysis revealed elevated levels of luteinizing hormone and follicle-stimulating hormone but an exaggerated gonadotropin response to luteinizing hormone-releasing hormone stimulation. The growth hormone response to insulin-induced hypoglycemia was also exaggerated. All sequences examined on the sex-determining region Y gene were present. The diagnosis was 46,XX male with the major manifestation of short stature.

Adolescent↗
PubMed1999

Flow-cytometric measurement of cellular changes in urine: a simple and rapid method for perioperatively monitoring patients after kidney transplantation.

OBJECTIVE: In renal transplant patients having graft dysfunction, it is usually difficult to obtain the accurate diagnosis, such as acute rejection, acute tubular necrosis, infection, or cyclosporin nephrotoxicity. An accurate diagnosis can provide the proper treatment of these patients, thereby lessening the chance of kidney loss. METHODS: A total of 42 patients were enrolled. By using the flow-cytometric technique, the white cell populations of urine in these patients were analyzed and linked to their clinical course. All patients underwent sonography-guided biopsy of the transplanted kidney with a definitive diagnosis. RESULTS: When 10% lymphocytes and 15% granulocytes in urine were set as the cutoff point of a normal ratio threshold, the flow-cytometric analysis presented the highest sensitivity and the highest negative predictive rate for acute tubular necrosis. However, a lower sensitivity and positive predictive rate was found in acute rejection cases. CONCLUSIONS: Our results suggest that flow-cytometric analysis of the urinary cell population can be used as an adjunct in patient follow-up after kidney transplantation.

Acute Disease↗
PubMed1999

Intracardiac echocardiography via the transvenous approach with use of 8F 10-MHz ultrasound catheters.

OBJECTIVE: To study the safety and feasibility of intracardiac imaging using a novel 8F 10-MHz non-over-the-wire ultrasound catheter system. SUBJECTS AND METHOD: Intracardiac imaging using a transfemoral venous approach was performed in 33 adults, 14 men and 19 women, aged 25 to 66 years (mean, 46 years). Six were normal subjects, 12 had congenital heart diseases (5 atrial septal defects, 3 ventricular septal defects, 1 tetralogy of Fallot, 2 patent ductus arteriosus, and 1 Ebstein anomaly), 14 had valvular heart diseases (12 mitral stenoses and 2 calcific aortic stenoses), and 1 had acute pulmonary embolism. RESULTS: Ultrasound images were obtained, without any complications, from the right side of the heart in all subjects. The atria and ventricles could be recognized by anatomic relationships to the cardiac chambers and the valves by their characteristic motion during each cardiac cycle. The vessels were verified by their connections to the cardiac chamber and by contrast echocardiography if indicated. CONCLUSION: Intracardiac imaging using the 8F 10-MHz non-over-the-wire ultrasound catheter system via a transfemoral venous approach is feasible and safe. Intracardiac echocardiography is potentially useful for assessing a variety of cardiac anomalies and in guiding and monitoring certain intervention procedures.

Adult↗
PubMed1999

Liver abscess secondary to fish bone penetration of the gastric wall: a case report.

An unusual case of liver abscess caused by fish bone perforation of the stomach is presented in this report. A 65-year-old woman was admitted to the Far Eastern Memorial Hospital for abdominal pain, fever and chills. Physical examination revealed anemia and tenderness in the epigastrium. Laboratory data showed leukocytosis and abnormal liver function. Computerized tomography of the abdomen disclosed a huge abscess in the left lobe of the liver. Exploratory laparotomy was performed and a fish bone, 3.7 cm in length, was found perforating the stomach with penetration into the left lobe of the liver, resulting in a hepatic abscess. Drainage of the liver abscess with removal of the fish bone and simple closure of the gastric perforation were performed. The patient recovered uneventfully.

Aged↗
PubMed1999

Coronary dissection and myocardial infarction following blunt chest trauma.

Myocardial infarction (MI) following blunt chest trauma is rarely diagnosed because the ensuing cardiac pain is commonly attributed to contused myocardium or the traumatic injuries in the local chest wall. There are only scattered reports on the coronary pathology associated with MI secondary to blunt chest trauma. Because differentiation of the pathology is difficult but important, we report here three cases of acute anterior MI secondary to coronary dissection following blunt chest trauma. Coronary dissection was demonstrated by coronary angiography. Two of the patients had intimal tears at the proximal left anterior descending artery (LAD) with normal flow, and the other patient had nearly total occlusion of the LAD associated with filling defects probably caused by an intracoronary thrombus. All three patients received conservative treatment without major complications and remained free from angina or heart failure throughout a 5-year follow-up period. In order to exclude associated MI in cases of blunt chest trauma, electrocardiography is necessary, and coronary angiography may be indicated to demonstrate coronary arterial pathology. Dissection of the coronary artery with subsequent thrombus formation is one of the possible pathophysiologic mechanisms of MI following blunt chest trauma.

Adult↗
PubMed1999

Plasma leptin concentrations are related to body fat mass and gender but not to thyroid dysfunction.

Leptin, a newly defined protein synthesized and secreted from fat cells in both animals and humans, has gained wide attention. Many studies have been conducted on its roles in the regulation of body fat storage, energy expenditure and body weight changes. Thyroid dysfunction is known to have influences on the above changes in humans and these changes may in turn lead to a variation in circulating leptin levels. In addition, a sex dimorphism of plasma leptin levels has been a constant finding in many studies. However, the relationship between body fat mass and gender to plasma leptin levels in patients with various thyroid dysfunction has been rarely discussed together. A total of 134 patients with various thyroid function status were included in this study (hyperthyroidism: n = 50, hypothyroidism: n = 24, and euthyroidism: n = 60). Plasma leptin concentrations were compared between different thyroid function groups, and compared with body fat mass and body mass index (kg/m2) to check if these two parameters affect the circulating leptin levels. There were no significant differences between plasma leptin concentrations in the different thyroid function groups (Mean +/- SD: hyperthyroidism: 8.5 +/- 5.4 ng/ml, range: 1.5-25.8; hypothyroidism: 8.4 +/- 4.7 ng/ml, range: 1.8-20.1, and euthyroidism: 7.3 +/- 4.5 ng/ml, range: 0.6-20.9). Rather, a significant gender difference was found, with female subjects having two-fold higher levels than males when all study subjects were encompassed (female: 8.8 +/- 4.9 ng/ml, range: 11.7-25.8 vs male: 4.1 +/- 2.1 ng/ml, range 0.6-8.1, p < 0.001) or when thyroid function status was analyzed separately (hyperthyroidism: female: 9.7 +/- 5.5 ng/ml vs male: 4.3 +/- 2.1 ng/ml, p < 0.001; hypothyroidism: female: 9.7 +/- 4.6 ng/ml vs male: 4.4 +/- 2.4 ng/ml, p = 0.015; and euthyroidism: female: 7.9 +/- 4.5 ng/ml vs male: 3.6 +/- 1.9 ng/ml, p = 0.013). Plasma leptin concentrations had strong correlation with body fat mass in both females (r = 0.47, p < 0.001) and males (r = 0.71, p < 0.001). Good correlation was also observed between plasma leptin concentrations and body mass index in females (r = 0.51, p < 0.001) and males (r = 0.78, p < 0.001). Plasma leptin concentrations were not different in thyroid dysfunction. A significant gender difference existed and a positive correlation between body fat mass and BMI to plasma leptin was observed.

Adipose Tissue↗
PubMed1999

Effects of "products of chicken embryo" on growth and sexual development in rats.

Products of Chicken Embryo (PCE) such as Ji-Pei-Jing is a kind of food for Chinese children prepared from chicken embryo. Female rats on 21 days were administered with aqueous solutions of Ji-Pei-Jing (1.2%, 3%, 12%, and 48%, respectively) by gavage up to their onsets of puberty. The rats in the control group were treated with distilled water. However, Ji-Pei-Jing treatment exerted some effects on sexual maturation in the immature female rats. Essentially, the effects showed a dose-response tendency with an inverted "U" shape. The age of vaginal opening for group treated with Ji-Pei-Jing was significantly earlier than that to the control. Its uterus weight/b.w. ratio also significantly increased on day 30 and at the first estrus. There were significantly increases in the adrenal weight/b.w. ratio of 30-day-old rats that were treated with 3%, 12%, and 48% Ji-Pei-Jing. The rats treated with 48% Ji-Pei-Jing had significantly lesser ovary weight/b.w. ratio on day 30, too. The rats treated with Ji-Pei-Jing could normally ovulate at the first estrus, and no significant differences were observed during estrous cycles. The effects of PCE on serum levels of E2, P, LH in 30-day-old rats and FSH in 28-day-old rats were elevated significantly by 3% Ji-Pei-Jing treatment. It appears that the effects of PCE result from interaction of contained complex physiologically active substances. Steroids, especially estradio-17 beta, possibly play a key role, and polypeptide hormones may also exert important effects.

Animals↗
PubMed1999

Primary stenting of the left main coronary artery in acute myocardial infarction complicated by cardiogenic shock: case report.

Although acute left main coronary artery (LMCA) occlusion is a rare angiographic finding, it carries a very high mortality rate and most of the patients with this clinical condition die from sudden death or cardiogenic shock due to malignant arrhythmia or pump failure. The high mortality rate and tendency to lead rapidly to death are chiefly related to extensive myocardial injury. We report a case of cardiogenic shock resulting from acute myocardial infarction. Emergency cardiac catheterization was performed and coronary angiography showed a totally occluded LMCA. Prompt revascularization by means of primary LMCA stenting was successful and the patient was discharged 2 weeks later with only mild congestive heart failure. We suggest that the rapid performance of angiographic studies in this patient with cardiogenic shock was the turning point in saving her life. We also suggest primary LMCA stenting as an effective procedure for saving lives because it may reverse cardiogenic shock and prevent a probable fatal outcome.

Aged↗
PubMed1998

Conversion of a radioresistant phenotype to a more sensitive one by disabling erbB receptor signaling in human cancer cells.

Inhibition of cell growth and transformation can be achieved in transformed glial cells by disabling erbB receptor signaling. However, recent evidence indicates that the induction of apoptosis may underlie successful therapy of human cancers. In these studies, we examined whether disabling oncoproteins of the erbB receptor family would sensitize transformed human glial cells to the induction of genomic damage by gamma-irradiation. Radioresistant human glioblastoma cells in which erbB receptor signaling was inhibited exhibited increased growth arrest and apoptosis in response to DNA damage. Apoptosis was observed after radiation in human glioma cells containing either a wild-type or mutated p53 gene product and suggested that both p53-dependent and -independent mechanisms may be responsible for the more radiosensitive phenotype. Because cells exhibiting increased radiation-induced apoptosis were also capable of growth arrest in serum-deprived conditions and in response to DNA damage, apoptotic cell death was not induced simply as a result of impaired growth arrest pathways. Notably, inhibition of erbB signaling was a more potent stimulus for the induction of apoptosis than prolonged serum deprivation. Proximal receptor interactions between erbB receptor members thus influence cell cycle checkpoint pathways activated in response to DNA damage. Disabling erbB receptors may improve the response to gamma-irradiation and other cytotoxic therapies, and this approach suggests that present anticancer strategies could be optimized.

Apoptosis↗
PubMed1998

Neoadjuvant chemotherapy followed by radiotherapy should not be a standard approach for locally advanced cervical cancer.

PURPOSE: To investigate the role of neoadjuvant chemotherapy followed by radiotherapy in locally advanced cervical cancer. METHODS AND MATERIALS: This study cites all known literature on the subject in the English language. Articles were selected for analysis by MEDLINE and CANCERLINE computer searches. In Phase II trials, the response rates of some selective series were analyzed. However, This article will specially emphasize the result of all Phase III randomized trials. RESULTS: Several investigators did obtain promising results from Phase II trials of neoadjuvant chemotherapy, mostly cisplatin-based combinations, followed by radiotherapy. However, most Phase III trials failed to demonstrate any benefit in terms of loco-regional relapse and/or survival by up-front chemotherapy. CONCLUSION: The role of neoadjuvant chemotherapy remains to be defined, and the search for more active new agents must be continued. The neoadjuvant setting is still experimental and could not be recommended as a standard treatment at the present.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Ultrasonography for inguinal hernias in boys.

BACKGROUND/PURPOSE: History taking and physical examination alone no longer meet the surgeon's need in the diagnosis of inguinal hernia. Ultrasonography (US) provides a good and safe diagnostic tool for inguinal hernias in boys. METHODS: From 1995 to 1997, 244 boys with inguinal hernias (41 bilateral and 203 unilateral), received preoperative US on both groins to confirm the diagnosis. Those with positive US findings, such as viscera or fluid in inguinal canal or widening of the internal inguinal ring, underwent surgery. RESULTS: The accuracy of diagnosis with US and clinical assessment were 97.9% and 84%, respectively. More than 95% of widening of internal inguinal rings (>4 mm) proved to be hernias. There were two direct inguinal hernias and two femoral hernias, which were misdiagnosed by clinical examination, but proved to be diagnosed correctly by US. CONCLUSIONS: US serves as a noninvasive and highly accurate diagnostic tool for inguinal hernias in boys. Using 4 mm as the upper limit of the normal diameter of the internal inguinal ring, an occult inguinal hernia can be easily detected before surgery.

Adolescent↗
PubMed1998

Transcriptional activation of NF-kappa B activity by Epstein-Barr virus (EBV) LMP1 as a selective therapeutic strategy for EBV-associated diseases.

Epstein-Barr virus (EBV) has been known to be associated with many malignant tumors, including nasopharyngeal carcinoma (NPC). Previous studies have indicated that an EBV-encoded oncoprotein, latent membrane protein 1 (LMP1), is expressed in many NPC tissues. LMP1 has been shown to stimulate HIV LTR through the two NF-kappa B binding sites within this promoter. In this study, we examined the feasibility of using this property of LMP1 as a therapeutic strategy for the treatment of NPC. This therapy consists of the preferential killing of the LMP1-expressing cells by gene transfer using the NF-kappa B-mediated herpes simplex virus thymidine kinase (HSVtk)/ganciclovir (GCV) system. The 800-bp HIV-LTR, which contains two NF-kappa B binding sites, was used to drive the HSVtk gene. Stable C33A cell clones expressing the LMP1 and the HSVtk genes were subjected to the GCV sensitivity test. Results showed that cells expressing both the LMP1 and the HSVtk genes were highly sensitive to GCV treatment. These cells were introduced into nude mice subcutaneously and tumors became palpable within 2 weeks. GCV was then introduced intraperitoneally to these mice and the sizes of the tumors were measured daily. Results showed that the tumors regressed in the group of mice carrying cells that stably expressed both the LMP1 and the HSVtk genes, but not in mice carrying cells containing LMP1 or HSVtk alone. Our data indicate that the HSVtk gene expressed from a NF-kappa B-binding motif-containing promoter that is regulated by LMP1 may be used as an in vivo gene therapy strategy of EBV LMP1-expressing cancers such as NPC.

Animals↗
PubMed1998

Mixed medullary-follicular carcinoma and papillary carcinoma of the same thyroid.

We report a rare case of mixed medullary-follicular carcinoma and papillary carcinoma of the same thyroid. A 27-year-old Chinese female complained of a single thyroid nodule for 2-3 months. Needle aspiration revealed suspicious papillary carcinoma and thyroidectomy performed later showed mixed medullary-follicular carcinoma and papillary carcinoma of the same thyroid which was extremely rare. Whether neoplastic transformation is due to tumorigenic stimulus or just due to the collision phenomenon is still controversial for its etiology.

Adult↗