Biomedical subjects
Publications and source records attributed to K T Chen.
Two cases of pulmonary coccidioidomycosis which were initially misdiagnosed as carcinoma in cytologic examinations of material obtained by bronchoscopy or fine-needle aspiration are reported. The cytodiagnostic pitfalls of misinterpreting reactive bronchial epithelial cells as carcinoma cells and of failing to recognize fungal organisms are discussed.
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There are a lot of immunological changes after major surgery, especially in open heart surgery when blood flows through a cardiopulmonary bypass system. We monitored leukocyte count, lymphocyte subpopulation count, soluble IL- 2 receptor (sIL-2r) and serum IL-2 levels, and an immunosuppressive acidic protein (IAP) level before and on the 1st, 7th, and 14th day after open heart surgery. It was noted that there were significant increases of total leukocyte and granulocyte counts for more than two weeks. But total lymphocyte, T-lymphocyte, b-lymphocyte, natural killer cell, suppressor T-cell, and helper T-cell all showed significant decreases in absolute numbers for more than one week as compared to the preoperative values. Serum IAP level was elevated for more than two weeks after operation. Serum IL-2 decreased but serum sIL-2R increased in the postoperative period. It is concluded that there is a period of immunosuppression after open heart surgery which lasts for at least one week and perhaps more than two weeks.
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Technology plays an important role in the practice of medicine, and it is essential that controlled clinical trials be conducted before new technologies are widely disseminated. In this article, information from the medical literature is summarized and critiqued for several common obstetric technologies which are aimed at reducing the incidence or sequelae of low birth weight and preterm birth. These technologies include home uterine activity monitoring, tocolytic drugs to suppress uterine contractions, corticosteriods to accelerate fetal lung maturity, bed rest to prevent preterm delivery, delivery methods, multifetal pregnancy reduction, and cervical cerclage. A major challenge to the practice of medicine is to find effective ways to modify physician behavior to encourage the use of proven, effective technologies, and discourage the use of unproven, ineffective technologies. Despite widespread use, most obstetrical technologies appear to have had little impact on reducing the incidence of low birth weight or preterm births, as rates of low birth weight and preterm birth have not decreased appreciably in the past 25 years. Uncovering the basic mechanisms responsible for the onset of preterm labor will undoubtedly facilitate the discovery of new technologies to prevent low birth weight and preterm births.
This study investigated the independent and combined effects of photodynamic therapy (PDT), laser photodynamic hyperthermia (LPDH) and 1-(4-amino-2-methyl-5-pyrimidinyl) methyl-3-(2-chloroethyl) -3-nitrosourea hydrochloride (ACNU) in a rat 9L induced gliosarcoma model. The mortality rate (MR60), mean survival time (MST60), and increasing life span (ILS60) within 60 days were determined to evaluate the therapeutic effect in vivo. The MR60 and MST60 of the gliosarcoma tumor control were 100% and 16.2 days. The ILS60s of PDT and ACNU were 72.84% and 49.81%, respectively, but MR60 of both were 86.72%. All combined treatments produced significantly prolonged survival (P < 0.01). The combined effects of LPDH and ACNU, MR60, MST60, and ILS60 were 60%, 43 days, and 165.4%, respectively. The ILS60 of PDT + ACNU (96.48%) and PDT + LPDH (98.58%) also indicated a synergistic or additive effect. The survival fraction and synthetic rate of DNA, RNA, and protein of glioma 9L tumor cells in vitro after single treatment of PDT or combined with antitumor drugs and laser showed that the cytotoxicity of PDT to 9L tumor cell was obvious by using Rh123, HPD, and Pf-II as photosensitizers. Combined treatments of PDT, antitumor drugs, and laser suppressed the synthesis of DNA, RNA, and protein more significantly than single treatment with PDT.
This study investigated school children in the Tung-Lo Township in central Taiwan to determine the prevalence of goiters compared to other areas of Taiwan and to elucidate the possible etiology. All children attending elementary schools in Tung-Lo were examined for thyroid enlargement by neck palpation, as recommended by the World Health Organization. Thyroid antibodies and thyroid hormones were determined in children with goiters, and in normal age- and sex-matched controls. Additionally, analysis of drinking water for humic substances was done by fluorospectrophotometry. In total, 1,823 school children were examined (965 boys and 858 girls). Of these, 174 (9.5%) were found to have a goiter of grade I or above. The prevalence was higher than our recent surveys in other areas of Taiwan (2.6%-8.8%). Goiter prevalence in school children residing in hill regions (12.9%), mainly dependent on underground water for drinking, was higher than that of school children residing in plain regions (8.2%), who depend on tap water for drinking. The quality of drinking water bore a close relationship to the prevalence of goiter. From the ratio of T3/T4 in this study, and a study of urinary iodine excretion done by others, it is concluded that goiters in Tung-Lo are not related to iodine deficiency. There was no statistically significant correlation between the relative fluorescence intensity of humic substances and the prevalence of goiter. The results of this study suggest that the higher prevalence of goiter in children living in Tung-Lo, an oil-bearing area, may be related to the quality of drinking water.
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BACKGROUND: Merkel's cell carcinoma rarely arises in the vulva. It is unclear whether those cases arising in the vulva behave differently from the usual Merkel's cell carcinomas. METHODS: A Merkel's cell carcinoma of the vulva was studied by light microscopy, immunohistochemistry, and electron microscopy. The clinical data of this case and of other reported cases are summarized and compared with those of Merkel's cell carcinoma in general. RESULTS: This tumor showed the characteristic trabecular pattern of Merkel's cell carcinoma. The tumor cells were immunoreactive to low-molecular-weight cytokeratin and neuron-specific enolase. This patient was treated initially with local excision. She died 17 months later with progressive metastatic disease unresponsive to chemotherapy. This case study and the review of six other cases indicate that Merkel's cell carcinoma of the vulva is universally metastatic, both to the regional lymph nodes and distant sites, and that it invariably follows a rapidly fatal course. CONCLUSION: Merkel's cell carcinoma of the vulva appears to have a biologic behavior more aggressive than that of Merkel's cell carcinoma in general. An initial modality combining chemotherapy, with or without irradiation, with aggressive surgery should be tried in future cases.
The cytologic and histologic features of two cases of psammocarcinoma of the peritoneum are reported. The previously proposed histologic diagnostic criteria for this tumor are expanded in order to accommodate the present two cases. The cytologic features of this tumor have not previously been reported.
Chuling (Polyporus umbellatus), one of the commonly used Chinese medical herbs, was combined with mitomycin C and then studied against intrahepatic implantation of sarcoma 180 tumor cells in mice. Oral administration of chuling extract, intraperitoneal injection of mitomycin C and the combination of both increased the life span of tumor-bearing mice 71.6%, 70.1% and 119.9%, respectively. The same treatments were found to be cytotoxic to Sarcoma-180-induced liver tumor cells. The synthetic rates of DNA, RNA and protein were all inhibited measurably by the combined treatment. Histopathological studies showed that lymphocytes infiltrated and surrounded the cancer cells, and there was some fibrosis found in normal cells and cancer cells. These results indicate the potential use of chuling as an anticancer agent.
The cell-killing effect and its possible mechanism of berberine used alone or in combination with argon ion laser treatment on 9L rat glioma cells were studied. The survival fraction of 9L cells after single treatment of berberine has been investigated using both colony formation and microtitration (MTT) method, the half lethal dose of berberine (LD50) has been estimated to be 60 micrograms/ml. After the addition of low energy laser treatment, the LD50 of berberine markedly decreased to 10 micrograms/ml. The inhibitory effect of berberine on biosynthesis for DNA, RNA, and protein of 9L cells was enhanced by argon ion laser. Moreover, when morphologic change was examined, the 9L cells showed lysis, encystation, and degeneration after berberine treatment; the laser treatment enhanced the cell-killing effect. The study proves the cell-killing effect of berberine combined with laser treatment on 9L rat glioma cell line, hence introducing the possibility of berberine as a photosensitive agent.
Motor-vehicle incidents in Taiwan are a major cause of head injuries. Our objective was to analyze the characteristics of head injuries caused by motor vehicle accidents in terms of the injured person's demographic characteristics, time and types of crash, injury severity on the abbreviated injury scale (AIS), medical cost and benefits of helmet protection. For this purpose we conducted an epidemiologic survey of 2451 consecutive victims of traffic accidents, coming to, or managed at, the emergency care department of a large Taipei metropolitan hospital in 1990. The results showed that the most common cause of head injury in traffic accidents was a motorcycle incident. Motorcycle accident injured patients were generally young males, laborers or students. Most head injuries occurred between 16:00 and 23:00, and peaking at 21:00 in a day. Forty-three points four percent of patients were admitted, major head injury fatalities occurred within one week of the collision. The elderly or patients with high AIS comprised most nonsurvivors. According to our data, helmet usage was about 14% overall. Helmetless young riders were numerous among the total victims. A significant difference was noted in the severity of injury of helmeted users of motorcycles, compared with those who wore no helmet. As expected, patients who did not wear a helmet had a greater AIS average and higher rate of fatality. Forty-one of the 42 fatalities were patients who had been riding on motorcycles without helmets. Helmets provide adequate protection and reduce severity of injury, and medical cost for motorcycle collisions.
In order to achieve a better speech result while eliminating the possible adverse effect to midfacial growth, a Furlow palatoplasty has been used for primary palatal repair as well as correction of velopharyngeal insufficiency in 54 patients since 1985. There were four oronasal fistulae in the 35 patients who received the procedure for primary palatal repair. These four patients were earlier cases in the series. There was no fistula in the patients operated on after July 1989. Among the 28 patients who had postoperative speech assessment, only two patients had velopharyngeal insufficiency (VPI). These unfavorable results were due to an inappropriate patient selection. For the 19 patients who received a Furlow palatoplasty for the correction of VPI, the results were also encouraging. The unfavorable results were also caused by incorrect patients selection. With increasing experience, the results of this technique should continue to improve.
Autogenous bone graft of an alveolar cleft area has the following advantages: (1) assistance in the closure of buccoalveolar oronasal fistula; (2) provision of bony support for unerupted teeth and teeth adjacent to the cleft; (3) formation of a continuous alveolar ridge to facilitate orthodontic correction of malocclusion; (4) supporting the nostril floor and alar base to improve nasal aesthetics. It has been well accepted in most craniofacial centers as routine procedure in cleft lip and palate rehabilitation. A new surgical technique for alveolar bone grafting has been introduced to the Chang Gung Craniofacial Center since July 1991. It provided a good exposure of the alveolar cleft, primary closure of the fistula and adequate volume of bone graft. A review of 27 consecutive alveolar bone grafting procedures performed in unilateral cleft lip and palate patients from July 1991 to June 1992 was presented. Patients have been followed up for at least 6 months. The alveolar bone graft was evaluated clinically and radiologically at one week, six months and one year after the surgery. The preliminary results indicated that the new surgical technique produced less chance of recurrent fistula, good postoperative gingival height, and improvement of nasal aesthetics. Based on the results of this new study we strongly advocate the use of this new surgical technique.
Congenital macrostomia or transverse facial cleft is a rare congenital craniofacial anomaly. It is usually associated with deformities of other structures developed from the first and second branchial arches and is thought to be part of the manifestations of hemifacial microsomia, the second most common congenital craniofacial anomaly. There were several methods to repair this deformity. All the methods emphasize the importance of restoration of the integrity of cheek and lip muscles. The role of vermilion flap and the size and direction of skin Z-plasty remained controversial. A retrospective review on the 16 congenital macrostomia patients repaired in this hospital by 4 different surgeons with 5 different methods was made. The symmetry of lip, commissural shape and scar quality were evaluated among different methods. It was felt that accurate positioning of the oral commissure and reconstruction of a functional oral musculature were quite important to a good result. The skin Z-plasty could lengthen the deficient transverse distance of the cheek tissue and prevent later scar contracture. But a Z-plasty needed careful design and good postoperative care to minimize visible scar. A vermilion flap across the commissure could also prevent the lateral migration of the commissure from a linear scar contracture. The flap also needed careful design to give a better commissural shape.
A 39-year-old woman had multiple osteomas of the gallbladder. She presented with right upper quadrant abdominal pain associated with leukocytosis. An ultrasound showed three small intraluminal gallbladder lesions with no apparent mobility. The lesions proved to be three small polypoid osteomas in the resected gallbladder. A review of the literature showed no previous report of this type of gallbladder neoplasm.
Unintentional hypothermia is common in patients undergoing "routine anesthesia in surgery". The aims of the study were to estimate the difference of changes of body temperature during abdominal and limb operations and to evaluate the effectiveness of the heated humidifier for reducing intraoperative heat loss. Forty-three patients were randomly being allocated into 3 groups. Group I consisted of 14 patients undergoing abdominal operation without the use of heated humidifier. Another 22 patients were being assigned as group II to have a heated humidifier on the inspiratory limb of the breathing circuit. The inspired gas was warmed to 39 degrees C and the relative humidity was 90%. 7 patients undergoing limb operation were attributed to group III without using heated humidifier to humidify and warm up the inspired gas. For body temperature monitoring, the probe was placed on the patient's nasopharynx and the temperature was measured immediately before induction of anesthesia, post-intubation, and then once again every 15 minutes up to 3 hours after induction. All patients in the 3 groups showed a rapid decrease of body temperature in the first hour and then the hypothermic change was slow down. The lowest level of body temperature was reached at about 2 hours after induction. Patients undergoing abdominal operation decreased body temperature greater than those undergoing limb operation for about 2 degrees C after 3 hours of anesthesia and surgery. Warming and humidifying the inspired gas effectively reduced the heat loss. We concluded that abdominal operation induce hypothermia more than limb operation. The use of heated humidifier was effective in maintaining body temperature.