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Biomedical subjects

C J Wang

Publications and source records attributed to C J Wang.

At least 145 records · Page 8Linked to original sources
PubMed1997

High-dose-rate intracavitary brachytherapy (HDR-IC) in treatment of cervical carcinoma: 5-year results and implication of increased low-grade rectal complication on initiation of an HDR-IC fractionation scheme.

PURPOSE: To report the treatment results and rectal/bladder complications of cervical carcinoma radically treated with high-dose-rate intracavitary brachytherapy (HDR-IC). The current policy of using three-fraction scheme was examined. METHODS AND MATERIALS: Between November 1987 and August 1990, 173 patients with cervical carcinoma were treated with curative-intent radiation therapy. Whole pelvic irradiation was administered with 10-MV X ray. Dose to the central cervix was 40-44 Gy in 20-22 fractions, following by pelvic wall boost 6-14 Gy in three to seven fractions with central shielding. 60Co sources were used for HDR-IC, and 7.2 Gy was given to Point A for three applications, 1-2 weeks apart. Duration of follow-up was 5-7.8 years. RESULTS: Twenty-eight patients (16%) developed central-regional recurrences. Overall 5-year actuarial pelvic control rate was 83%. By stage, 5-year actuarial pelvic control rates were 94%, 87%, and 72% for Stages IB + IIA, IIB + IIIA, and IIIB + IVA, respectively. Thirty-one patients (18%) developed distant metastasis. Overall 5-year actuarial survival rate was 58%. By stage, 5-year actuarial survival rates were 79%, 59%, and 41% for Stages IB + IIA, IIB + IIIA, and IIIB + IVA, respectively. Sixty-six (38%) and 19 patients (11%) developed rectal and bladder complications, respectively. For rectal complication, the overall actuarial rate was 38% at 5 years. By grade, 5-year actuarial rectal complication rates were 24%, 15%, 4%, and 3% for Grades 1-4, respectively. Overall prevalence of rectal complications was 37% and 14% at 2 and 5 years, respectively. Prevalence of low-grade rectal complication (Grades 1 and 2) was dominant at 2 years (30%), but declined to 8% at 5 years. Prevalence of high-grade, severe rectal complication (Grades 3 and 4) remained steady at 2 and 5 years (7% and 6%, respectively). Five-year actuarial bladder complication was 9%. Five-year prevalence of bladder complication was 2%. CONCLUSION: Using a three-fraction scheme, survival rate appeared comparable with the existing results of the low-dose-rate technique. The incidence of rectal complication with this scheme remained relatively high. The increased part of rectal complication was predominantly low grade. This result suggested that therapeutic gain with this scheme may not be good enough to circumvent its biologic disadvantage. Numbers of fractions >3 must be considered in future trials.

Adenocarcinoma↗
PubMed1997

Combined-modality therapy for squamous carcinoma of the buccal mucosa: treatment results and prognostic factors.

BACKGROUND: Reports on locoregional control and survival of squamous cell carcinoma of buccal mucosa are scarce in literature. In this study, a single institutions's experience of combined surgery and postoperative radiotherapy (RT) for buccal mucosal malignancy with favorable results was analyzed and presented. The prognostic factors on locoregional control were also discussed. METHODS: From January 1988 to July 1994, 57 patients with squamous cell carcinoma of buccal mucosa treated by surgery and RT were reviewed. The distributions according to American Joint Committee on Cancer (AJCC) staging were: stage II, 6; stage III, 21; and stage IV, 30 patients. Total dose of RT at the buccal area ranged from 45 Gy to 68.4 Gy, median 61.2 Gy. Tumor-related factors (AJCC stage, T stage, histologic grading, pathologic tumor invasion to skin of cheek, adjacent bony structures, and regional lymph nodes) and treatment-related factors (surgical margin, radiation dose, and the time interval between operation and RT) were analyzed to determine their influence on locoregional control. RESULTS: Three-year actuarial locoregional control rate, overall survival rate, and disease-specific survival rates were 64%, 55%, and 62%, respectively. Ten of these 22 patients (45%) with recurrent tumors were reoperated, but only 2 patients were successfully salvaged. Positive surgical margin and tumor invasion to skin of cheek were significantly poor prognostic factors on locoregional control by univariate analysis. In multivariate analysis, tumor invasion to skin of cheek was the only prognostic factor (p = .0014). CONCLUSIONS: Locoregional failure was the major cause of death for squamous buccal mucosa cancers managed with surgery and RT. Few recurrences could be detected early and successfully salvaged. Skin of cheek involvement is an important prognostic factor for buccal mucosa cancers.

Actuarial Analysis↗
PubMed1997

Tuberculous arthritis of the elbow.

Twenty-three patients with tuberculous arthritis of the elbow were treated and followed up for 3 to 8 years. The diagnosis was established by finding mycobacterium tuberculosis in the aspirate or in a surgical specimen in 18, and by histology in 5. A long history of symptoms and extensive involvement of bone and joint are associated with poor results. Early diagnosis and adequate treatment can be followed by good functional results. Postoperative continuous passive motion is valuable in improving the range of movement in elbows with extensive osteoarticular tuberculosis.

Adult↗
PubMed1997

A study of the referral patterns of obstetric clinics and the performance of receiving neonatal intensive care units in Taiwan.

To study the referral patterns of obstetric clinics, and the performance of receiving intensive care units measured by the survival of transported neonates, transport records were collected prospectively between July, 1991 and June, 1992. Two hundred and fifty-four transported neonates born in 51 obstetric clinics (level I units) in Tainan City and County, in southern Taiwan, were enrolled in this study. Nineteen percent of the transported neonates were very low birthweight infants (< 1500 g). Nearly equal numbers of them were transported to eight district hospitals (level II units) and to a tertiary center (level III unit), but these infants were 1.5 times more likely to die in a level II unit than a level III unit. In addition, equal numbers of infants assisted by mechanical ventilators were transported to level II and III units, but these infants were three times more likely to die in a level II unit than a level III unit (P = 0.006). Seventy-seven percent of the normal birthweight infants (> or = 2500 g) were transported to level II units, and the mortality in this group was 12.3% compared with 0% in those transported to the level III unit. Approximately 56% of these normal birthweight infants in level II units died of severe birth asphyxia. The referral patterns of level 1 units had an unfavorable effect on the survival of neonates requiring mechanical ventilation. Enhancing the skills of the staff in level I units to recognize and stabilize such infants, elevating the capability of level II units in treating some of these cases, and increasing the hospital beds for level III care are necessary to increase their chance of survival.

Health Services Research↗
PubMed1997

Effect of megestrol acetate and prepulsid on nutritional improvement in patients with head and neck cancers undergoing radiotherapy.

BACKGROUND AND PURPOSE: Anorexia is a common problem in cancer patients who receive radiotherapy. In this current study, we attempt to determine the effect of megestrol acetate and prepulsid on appetite and nutritional improvement in patients with head and neck cancers undergoing radiotherapy. MATERIALS AND METHODS: One hundred twenty-nine consecutive patients with head and neck cancers treated between July 1993 and June 1994 were prospectively randomized to receive either megestrol acetate, 40 mg qid (megace group), prepulsid, 5 mg tid (cisapride group), or a placebo treatment (control group) during radiotherapy. Before radiotherapy, body weight (kg), appetite score, performance status, biochemical parameters and hematological parameters were evaluated, and the above-noted clinical and biochemical parameters were assessed and recorded every other week. All patients received 6- 10 MV X-rays or Co-60 gamma-ray to head and neck region for a full course of radiotherapy, 61.2-75.6 Gy/7-9 weeks. RESULTS: Forty-eight patients were enrolled in the megace group, 41 patients in the cisapride group, and 40 patients in the control group. At the 2nd, 4th, 6th and 8th week, as the radiation dose escalated, the megace group had significantly less body weight loss than did the cisapride and control groups (P = 0.045, 0.024, 0.006, 0.003, respectively). The appetite scores of the megace group were significantly higher than those of the cisapride and control groups (P = 0.0001). However, there were no statistically significant differences in the change of albumin level among these three groups at the 2nd, 4th, 6th and 8th week (P > 0.05, respectively). CONCLUSIONS: Megestrol acetate can significantly decrease the degree of body weight loss, and can prevent the deterioration of appetite in patients with head and neck cancers receiving radiotherapy. However, prepulsid lacks the above-mentioned clinical benefits.

Adult↗
PubMed1997

The relapse patterns and outcome of postoperative recurrent tongue cancer.

PURPOSE: The relapse patterns and salvage treatment results for patients who developed locoregional recurrence after surgery for squamous cell carcinoma of the tongue were retrospectively analyzed. MATERIALS AND METHODS: Between April 1986 and January 1995, 77 cases with recurrent squamous cell carcinoma of the tongue were evaluated. Most of them were males in the early stages of initial disease. Although the surgical margins were negative in most cases (67 of 77), relapse eventually occurred. The relapse patterns showed 15 patients with primary recurrence, 45 patients with regional neck lymph node (LN) relapse, and 17 patients with relapse in both sites. RESULTS: Salvage treatment was given to most of the patients, but their median survival time was only 9 months. Survival data were analyzed and compared with different types of relapse patterns, salvage treatments, disease-free intervals, age, and sex. In univariate analysis, the neck LN relapse and shorter relapse-free interval (< 6 months) were poor prognostic factors (P < .05), and surgical treatment showed a trend for better salvage results (P = .0575). In multivariate analysis, patients with neck LN relapse had the worst outcome (P < .05). CONCLUSIONS: Recurrence of tongue cancer is not uncommon, but there are little data in literature regarding the prognosis. Although this study showed poor salvage results, various prognoses could be predicted on the bases of the different relapse patterns and salvage methods.

Adult↗
PubMed1997

Protective effects of dried flower extracts of Hibiscus sabdariffa L. against oxidative stress in rat primary hepatocytes.

Dried flower extracts of Hibiscus sabdariffa L., a local soft drink material and medical herb, was found to possess antioxidant activity in the present study. In the preliminary studies, antioxidant potential of three fractions of the ethanol crude extract (HS-C: chloroform-soluble fraction; HS-E: ethyl acetate soluble fraction; HS-R: residual fraction) obtained from the dried flowers of Hibiscus sabdariffa L. were evaluated by their capacity of quenching 1,1 -diphenyl-2-picrylhydrazyl (DPPH) free radical and inhibiting xanthine oxidase (XO) activity. HS-E showed the greatest capacity of scavenging free radical (EC50=0.017mg/ml), and HS-C showed the strongest inhibitory effect on XO activity (EC5o=0.742 mg/ml). Furthermore, antioxidant bioactivities of these crude extracts were investigated using a model of tert-butyl hydroperoxide (t-BHP)-induced oxidative damage in rat primary hepatocytes. All fractions were found to inhibit significantly the unscheduled DNA synthesis (UDS) induced by t-BHP at a concentration of 0.20 mg/ml. HS-C and HS-E also decreased the leakage of lactate dehydrogenase (LDH) and the formation of malondialdehyde (MDA) induced by t-BHP (1.5 mM) considerably at a concentration of 0.10 and 0.20 mg/ml in the rat primary hepatocyte cultures. These results indicated that the dried flower extracts (HS-C and HS-E) of H. sabdariffa L. protect rat hepatocytes from t-BHP-induced cytotoxicity and genotoxicity by different mechanisms.

Animals↗
PubMed1997

Two tandemly repeated telomere-associated sequences in Nicotiana plumbaginifolia.

Two tandemly repeated telomere-associated sequences, NP3R and NP4R, have been isolated from Nicotiana plumbaginifolia. The length of a repeating unit for NP3R and NP4R is 165 and 180 nucleotides respectively. The abundance of NP3R, NP4R and telomeric repeats is, respectively, 8.4 x 10(4), 6 x 10(3) and 1.5 x 10(6) copies per haploid genome of N. plumbaginifolia. Fluorescence in situ hybridization revealed that NP3R is located at the ends and/or in interstitial regions of all 10 chromosomes and NP4R on the terminal regions of three chromosomes in the haploid genome of N. plumbaginifolia. Sequence homology search revealed that not only are NP3R and NP4R homologous to HRS60 and GRS, respectively, two tandem repeats isolated from N. tabacum, but that NP3R and NP4R are also related to each other, suggesting that they originated from a common ancestral sequence. The role of these repeated sequences in chromosome healing is discussed based on the observation that two to three copies of a telomere-similar sequence were present in each repeating unit of NP3R and NP4R.

Base Sequence↗
PubMed1997

Microtubule active taxanes inhibit polycystic kidney disease progression in cpk mice.

Homozygous cpk/cpk mice develop polycystic kidney disease and die of uremia between the fourth and fifth weeks of age. Cpk/cpk mice treated weekly with paclitaxel (Taxol) can live to over six months of age. This dramatic moderation of polycystic kidney disease progression has been postulated to be a result of paclitaxel's ability to stabilize microtubules. In this study, the ability of taxanes with differing abilities to promote spontaneous in vitro assembly of tubulin dimers into microtubules were tested for their ability to inhibit the progression of polycystic kidney disease in polycystic cpk/cpk mice. We found that taxanes that are active in promoting microtubule assembly, including paclitaxel, 10-deactyl-taxol and cephalomannine increased the survival of polycystic cpk/cpk mice significantly longer than control animals. In contrast, the microtubule inactive taxane baccatin-III has no effect on the progression of renal failure in cpk/cpk mice. We conclude that the ability to promote microtubule assembly may be necessary for paclitaxel and related taxanes to modulate the progression of polycystic kidney progression in cpk/cpk mice.

Alkaloids↗
PubMed1997

Augmentation of protein kinase C activity and liver cell proliferation in lead nitrate-treated rats.

It is shown that lead alters calcium mediated cellular processes in several biological systems. Calcium enhances the activity of protein kinase C (PKC) which takes part in eliciting cell mitosis. In this study, the effects of lead nitrate on the activity of PKC enzyme were investigated in rat liver. The PKC activity was determined at 12, 24, 48, 72, 120, 168 hours after treatment with a single dose of lead nitrate in male Wistar rats. The results showed that the specific PKC activity of the purified particulate fraction was increased and reached a maximum at 24 hour, and lasted for 48 hours. This augmented activity of PKC was parallel with the increase of the lead level in the purified particulate fraction, although the protein levels of PKC alpha, PKC delta and PKC zeta were unchanged. Moreover, the frequency of mitotic cells also exhibited a significant increase, and like PKC activity, reached its maximum at 24 hour with accompany signs of liver enlargement. The results suggest that the PKC activation may be involved in promoting liver cell proliferation in lead nitrate-treated rats.

Animals↗
PubMed1997

Liver involvement in epidemic haemorrhagic fever: in situ hybridization, immunohistochemical and pathological studies.

In the present study, liver biopsy specimens from 37 patients with epidemic haemorrhagic fever (EHF) were investigated by using light and electron microscopy, immunohistochemistry for the EHF virus envelope protein G2 and in situ hybridization (ISH) for EHF viral RNA. Immunostaining and in situ hybridization were both positive, and a few of the aetiological agents, the EHF virus (EHFV) particles, were found individually within the dilated Golgi cisternae and vesicles, and the dilated rough endoplasmic reticulum of the hepatocyte. The pathological alterations of the liver cells infected with EHFV were: hepatocellular degeneration, cytoplasmic vacuolation, and spotty necrosis; moreover, zonal necrosis was present and adjacent to the narrowed and occluded sinusoids. In degenerated and spotty necrotic cells, the positive signals from of ISH for EHFV RNA and those from immunostaining for the virus protein were both stronger than those in the zonal liver cell necrosis area. The results showed that hepatocellular degeneration and spotty necrosis might be directly related to the virus and its duplication inside the liver cells, while the zonal necrosis was ischaemic and thought to be caused by microcirculation dysfunction.

Adolescent↗
PubMed1997

Molecular biology of hepatitis D virus: research and potential for application.

Superinfection by hepatitis D virus (HDV) leads to acute hepatitis and causes progression to liver cirrhosis in a significant proportion of hepatitis B surface antigen (HBsAg) carriers. Current regimens (interferon) to treat hepatitis D patients has only transient but no lasting effects. New approaches are, therefore, warranted. Recently, several laboratory studies have discovered interesting properties of HDV that may become targets for antiviral chemicals. Viral replication requires the small hepatitis delta antigen (s-HDAg). The s-HDAg is a nuclear phosphoprotein. There is evidence indicating that phosphorylation is important for HDV replication. A second step of replication requires HDV-RNA self-cleavage and self-ligation. Interestingly, one group of antibiotics, the aminoglycosides, exerts strong suppression effects on HDV ribozyme activities. In the following stage of viral assembly, two post-translational modifications, namely isoprenylation of large HDAg and glycosylation of HBsAg are involved. Agents capable of blocking the two modifications should reduce viral production. These four possible targets are reviewed. For prevention, effective vaccines are not yet available. Two novel approaches are discussed. The first demonstrates the immunogenicity of a nucleic acid vaccine in mice. The second approach assembled an empty HDV particle in yeast. Advances on such laboratory investigations may provide new methods for the control of hepatitis D in the future.

Aminoglycosides↗
PubMed1997

Dislocation of total knee arthroplasty. A report of 6 cases with 2 patterns of instability.

We report 6 cases of dislocation of total knee arthroplasty (TKA). We identified 2 patterns of instability in the sagittal plane, one with posterior translation of the tibia, occurring mainly in the postoperative period and usually resulting from a trauma, and the other with anterior translation of the tibia, occurring 6 months to 7 years postoperatively and with no preceding trauma. In the latter group, instability was manifested gradually as a lengthening of the posterior cruciate ligament and the posterior capsule, leading to a recurvatum deformity of the knee.

Aged↗
PubMed1997

Pituitary transplantation--a study on the response of hypophysis-adrenal axis to physiological stress.

Previous studies on experimental intracerebral pituitary transplantation have shown survival and possible function of fetal pituitary glands grafted to the hypothalamic region of inbred strains. In the present study, fetal pituitary tissue was implanted into hypothalamic area of the hypophysectomized rat by stereotactic methods. We investigated the hormonal levels and secretions of fetal pituitaries grafted to the allogenic host and studied the effects of physiological stimuli on hypophysectomized rats with grafted pituitaries. We found that the fetal pituitary allografts released adrenal corticotropin (ACTH) and corticosterone in response to stimulation by corticotropin-releasing hormone (CRH), and released corticosterone alone in response to insulin-induced hypoglycemia. The grafts are acutely responsive to CRH and retain their potential for physiological regulation and function. The ACTH-releasing-signal generated in the host by insulin-induced hypoglycemia failed to activate the graft, so activation by other physiological stimuli cannot be ruled out.

Adrenal Glands↗
PubMed1997

Anatomy and pathology of the septal region.

Comprising the septal area and the subcortical nuclei, the septal region is gray matter structures with widespread projection systems and different neurotransmitters. Although their function is poorly understood, lesions of the septal nuclei result in a syndrome of hyper-reactivity, amnesia, and hypersexuality. The pathologic processes affecting the septal region are discussed.

Amnesia↗
PubMed1997

Management of infected total knee arthroplasty.

BACKGROUND: Deep wound infection after total knee arthroplasty is an infrequent but very serious complication. Treatment is difficult and challenging. Antibiotic therapy alone can not replace surgery in the management of infected total knee arthroplasty. METHODS: Fourteen infected total knee arthroplasties in 13 patients were treated by the author. Nine patients underwent two-stage reimplantation, one patient one-stage reimplantation, one patient arthroscopic debridement, and one patient knee fusion. Four knees in three patients were excluded because of less than 12 months follow-up. This study retrospectively analyzed the results of treatment in 10 infected total knee arthroplasties in 10 patients. RESULTS: All patients were followed up for 12 months or longer. The length of follow-up ranged from 12 months to 69 months with an average of 28 months. All infections were successfully controlled, and there was no recurrence of infection. However, only 67% of the patients showed satisfactory functional results. CONCLUSION: Based upon the results in this study, most of the infection after total knee arthroplasty could be successfully controlled by combined surgical treatment and intravenous antibiotic therapy. The result of two-stage reimplantation was more consistent and predictable. The functional result of infected total knee arthroplasty was less satisfactory as compared with that of the non-infected counterpart. Furthermore, the impact of infection or the longevity of total knee prosthesis could only be determined by long-term follow-up.

Aged↗
PubMed1997

[Participatory action-research in the development of health policies for Izumo City, Japan].

The method of participatory action-research has been introduced in planning and implementing health and welfare projects for the elderly in Izumo City since 1993. Public health researchers have participated in the projects with other related administrative sectors, citizen and non-profit organizations. This study analyzes the establishment and implementation of health policies of Izumo from the following five aspects: policy-making, priority, education, intersectoral cooperation and community development. The participatory action-research method was useful for developing the ability of health-staff to work with citizens; for integrating community care and community development; for using community resources effectively for primary health care; and for developing community-based education of citizens, medical students and health staff. This method can be and should be adopted for strengthening the policy-making ability of public health researchers who learn through cooperation with citizens and non-profit organizations.

Community Participation↗