Search PubMed⌕ Search

Biomedical subjects

C C Sun

Publications and source records attributed to C C Sun.

At least 55 records · Page 3Linked to original sources
PubMed1996

Outbreak of contact dermatitis related to Acticide EP paste in a paint manufacturing factory.

An outbreak of severe itching, erythematous and edematous dermatitis over the extremities and upper back developed in 8 of 17 workers in the raw-materials department of a paint manufacturing factory. The outbreak occurred during a 2-month period when Acticide EP paste (Thor Chemical, Cheshire, UK) was used in place of Metatin as a microbiocide (Acima Chemical, Buchs, Switzerland). To evaluate the frequency and the etiologic agent of this outbreak, a plant walk-through, examination and review of photographs of skin lesions followed by statistical analysis for association between the development of dermatitis and exposure to Acticide paste were performed. Three guinea pigs were subjected to patch tests comparing the dermatotoxicity of Acticide EP and Metatin. The results showed that 8 out of 17 workers (47%) suffered from contact dermatitis during the 2-month period. Stratification by occupational exposure further confirmed the association between the development of dermatitis and exposure to the Acticide paste. The dermatotoxicity test on guinea pigs revealed the marked corrosive effect of the paste and the absence of dermatotoxicity of Metatin. After the removal of the paste from the raw material, there were no new cases of contact dermatitis at the 6 month follow-up. We conclude that Acticide EP paste was the responsible offending agent. Because isothiazolinone derivatives are well-known antigens and 2-n-octyl-4-isothiazolin-3-one is the active ingredient in Acticide EP paste, 2-n-octyl-4-isothiazolin-3-one is the likely cause of the dermatitis.

Animals↗
PubMed1996

Bipyridyl dihydrochloride inhibits tumor necrosis factor-alpha secretion by human keratinocytes on ultraviolet irradiation.

Paraquat manufacturers in Taiwan have been found to develop solar lentigo, actinic keratosis, as well as skin cancer in sun-exposed areas. Bipyridine has been found to be the responsible agent. At present, the mechanism for the pathogenesis of bipyridine-induced skin cancer is not known and it may be multifactorial. We investigated possible alterations in tumor necrosis factor (TNF)-alpha secretion in keratinocytes treated with 4,4'-bipyridyl dihydrochloride in vitro. Normal human keratinocytes were cultured and treated with bipyridine (10 micrograms/mL) or ultraviolet B (UVB) light (10 mJ/cm2), or with a combination of both. Bipyridine treatment alone resulted in a significant reduction in constitutive TNF-alpha secretion. Furthermore, in contrast to the finding in normal keratinocytes, UVB irradiation failed to promote TNF-alpha secretion in bipyridine-primed keratinocytes.

Humans↗
PubMed1995

Pulmonary vein stenosis.

Pulmonary vein stenosis (PVS) is a rare disorder. Accurate diagnosis often requires anatomical examination. We report four children with pulmonary vein stenosis. Autopsy showed bilateral lesions in two patients who were thought clinically to have unilateral disease. A diagnosis of PVS was made at autopsy in the third case. Intimal and medial fibromuscular proliferation was noted in extrapulmonary and intrapulmonary veins. Some of the fibromuscular proliferation were eccentric, resembling organized thrombi. In one case a focal organizing thrombus was found in a clinically unobstructed but anatomically narrowed veno-atrial junction. In another case injection of contrast medium into the stenotic pulmonary vein (PV) showed anastomosis between PV and bronchial vessels as well as small pulmonary arteries. Bilateral hypertensive arteriopathy was observed in unilateral and bilateral PVS. Our histological finding of intrapulmonary venous lesions in the lobes in which PVS was not detected clinically suggests that during surgical correction of unilateral PVS multiple biopsies of the opposite lung may help to evaluate possible bilateral disease. Our study also suggests that thrombosis in a stenotic pulmonary vein may further compromise the lumen and contribute to the progression of pulmonary vein obstruction. The possible pathogenesis of bilateral pulmonary hypertensive arteriopathy in unilateral PVS also is discussed.

Biopsy↗
PubMed1995

Photodamage and skin cancer among paraquat workers.

BACKGROUND: Some workers in paraquat manufacturing, exposed to bipyridines, have developed pigmentation and keratosis on sun-exposed skin. This condition has been described as skin-malignancy or premalignancy. This study was designed to clarify the pathologic features of these lesions and to explore the etiologic role played by bipyridine. METHODS: Twenty-three biopsy specimens, obtained from the affected skin of 10 workers, were scrutinized by a dermatopathologist. A total of 242 exposed workers from 28 paraquat factories were examined and interviewed during the period from 1983 to 1991. The severity of the characteristic skin lesions was graded from the lowest to the highest response to analyze the data by Mantel extension for a trend that focused on the heavy exposure to bipyridines as risk factor. RESULTS: All pathology specimens showed various degrees of solar damage: early actinic change, solar lentigo, actinic keratosis (AK), AK coexisting with squamous cell carcinoma (scc), and scc. Six specimens from four workers were scc or scc in situ. Three of six scc showed the coexistence of AK. Of the workers, 133 had skin lesions ranging in severity from grade 1 to grade 3 on sun-exposed areas. The severity of skin changes is strongly associated with heavy exposure to bipyridines (P < 0.0001). CONCLUSION: This pathologic study proves that all the lesions showed either photodamage or skin cancer. The strong trend in the correlation between severity of photodamage and exposure to bipyridine leads to the speculation about the synergistic role of bipyridine exposure and the solar effect in causing these malignant and premalignant skin lesions.

Adult↗
PubMed1995

Sulfur spring dermatitis.

44 cases of an unusual condition, designated hot spring dermatitis, have been studied. Patients usually presented during the winter months with a history of having taken green sulfur spring baths within the previous 2-20 days. Skin lesions developed about 24 h after bathing and were distributed generally over the trunk and limbs, especially in the skin folds. No micro-organisms were found in either hot spring water specimens or skin lesions. Patch tests showed no positive reactions. Investigations were undertaken to determine the physicochemical characteristics of the hot spring. In its extreme acidity and high content of soluble sulfur and chloride, it differed from other nearby hot springs.

Adult↗
PubMed1995

Occupational hand dermatitis in a tertiary referral dermatology clinic in Taipei.

Occupational skin disease is one of the most common occupational diseases. The hand is the most frequent site of involvement in occupational skin disease. We interviewed and examined patients seen in the Contact Dermatitis Clinic of the National Taiwan University Medical Center, a tertiary referral center in Taipei City. For patients suspected of having allergic skin diseases, patch testing was carried out using the European standard series and suspected allergens. Occupational hand dermatitis (OHD) was diagnosed according to medical history, work exposure, physical examination, and patch test findings. 36% of patients seen were diagnosed as having OHD. Electronics, hairdressing, medical, chemical, and construction were the most important industries causing OHD. In the 164 patients with OHD, 58.5% had irritant contact dermatitis (ICD) and 41.5% allergic contact dermatitis (ACD). Dorsal fingers, nail folds, and dorsal hands were most frequently involved in patients with ACD; dorsal fingers, volar fingers and fingertips were most frequently involved in those with ICD. Using logistic regression analysis, we were able to identify the most important clinical presentations that predicted the types of OHD, ACD versus ICD. Patients with atopic history and palm involvement were more likely to have ICD, and those with nail fold involvement more likely to have ACD. In patients with ACD, the most important allergens were dichromate, nickel, cobalt, fragrance mix, epoxy resin, thiuram mix, and p-phenylenediamine. In this study, we identified the important industries and causal agents for OHD. Future preventive measures focused on these industries and agents to reduce OHD will be warranted.

Academic Medical Centers↗
PubMed1995

'Microgastria--limb reduction' complex with congenital heart disease and twinning.

We report a newborn, the second of male twins, with multiple abnormalities, including microphthalmia, a complex cardiovascular malformation, asplenia, anomalous lobation of the lungs, oesophageal atresia, microgastria, intestinal malrotation, anal atresia, multicystic dysplastic kidneys, and reduction defects of the upper extremities. These defects fit into the so-called 'microgastria-limb reduction' complex. Two of twelve previously reported patients with this complex were from discordant twin pairs. The occurrence of twinning in three out of 13 cases suggests that the origin of the 'microgastria-limb reduction' complex may be related to the process of twinning itself.

Abnormalities, Multiple↗
PubMed1994

[Threshold of contact allergy to stearamidoethyl diethylamine in guinea pigs].

The cationic surfactant, stearamidoethyl diethylamine (SD) is an emulsifier used in topical medications and cosmetics. It has been reported to cause allergic contact dermatitis. This report concerns a study of the sensitizing capacity of SD in guinea pigs, using the modified maximization method (8) and closed epicutaneous test (10); the induction concentration was 10% in petrolatum. By the modified maximization method, 8 of 20 (40%) of the guinea pigs were sensitized to 1% SD, mean response 1.9; and 6 (30%) to 0.5% SD, mean response 1.4. In closed epicutaneous tests, 3 of 20 (15%) guinea pigs also showed reactions to 1%, and 2 of 20 (10%) to 0.5% SD. The results from modified maximization test showed that SD is a moderate sensitizer, as the sensitizing rate is in the range of 26-50% (below 26% is classified as "mild", and above 50% is "strong"). Even with a less sensitive closed epicutaneous test, its sensitivity could also be detected. From a risk-benefit point of view, no substantial risk for cosmetic chemicals intended for extensive use on normal and diseased skin will be accepted. Drugs may be acceptable, in spite of their sensitizing potential, because of their inherent benefit. As such, this surfactant may be only suitable in prescription drugs. Allergic contact dermatitis is rarely reported from cationic surfactants. Lack of suspicion of these not-necessarily-innocent chemicals has been partially responsible. The potential widespread use of emulsifiers with sensitizing capacity warrants further surveillance, as does the possibility of cross reaction between various emulsifiers.

Animals↗
PubMed1993

Dermatophyte pseudomycetoma: a case report.

A 25-year-old man presented with several prominent subcutaneous masses in the occipital region of the scalp. He had a long history of tinea capitis and tinea corporis infection. Histopathology of the occipital lesions showed mycelial aggregates in the deep dermis and subcutis. Cultures of the excised material and superficial scales grew a fungus identified as Microsporum ferrugineum. We propose the term 'dermatophyte pseudomycetoma' to describe this distinctive mycosis.

Adult↗
PubMed1993

[Pheochromocytoma nuclear pattern analysis by flow cytometry].

Flow cytometric nuclear DNA analyses were performed on paraffin-embedded tissue samples taken from 39 patients with pheochromocytoma treated between 1981 and 1992. The Hedley technique was used for measurement of nuclear DNA contents. Only 30 cases out of the 39 tumors were available for the determination of DNA ploidy analyses. Ten cases (33.3%) showed a diploidy pattern, 8-cases (27%) showed an aneuploidy pattern and 12 cases (40%) revealed a tetraploidy pattern. Four cases of malignant pheochromocytoma with regional or distal metastasis had been noted during a mean follow-up period of 4.75 years. All these four cases showed tetraploidy nuclear pattern with vascular invasion on pathological examination, which was statistically significant (p < 0.001) in differentiation between benign and malignant pheochromocytoma. About one third of patients with tetraploidy appeared to have malignant tendencies and this was statistically significant (p < 0.05). None of the patients with either diploidy or aneuploidy pattern had disease progression. The location of the tumor (adrenal vs. extra-adrenal) and 24 hours urine total vanillylmandelic acid (VMA) amounts were not significantly different from the diploid, aneuploid or tetraploid groups. These results suggested that nuclear DNA ploidy pattern is an important independent, and useful prognostic factor for patients with pheochromocytoma.

Adrenal Gland Neoplasms↗
PubMed1993

Rapid growth of pseudoangiomatous hyperplasia of mammary stroma in axillary gynecomastia in an immunosuppressed patient.

Pseudoangiomatous hyperplasia of mammary stroma is a rare, benign mesenchymal proliferation that sometimes mimics angiosarcoma. To our knowledge, it has not been reported in men. We report the first case of this unusual entity in a man. This case was most unusual in that it occurred in a clinical setting of immunosuppression, in axillary gynecomastia, and was growing rapidly.

Adult↗
PubMed1992

An unusual mosaic karyotype detected through prenatal diagnosis with duplication of 1q and 19p and associated teratoma development.

A 40-year-old white woman underwent amniocentesis for advanced maternal age at 15.4 weeks gestation. Fetal chromosome analysis demonstrated two distinct cell lines: [46,XX,t(1;19)(p11;p11)]--10%; and [47,XX,t(1;19)(p11;p11) + der(1)t(1;19)(p11;q11)]--90%. The latter karyotype was trisomic for both 1q and 19p. The mother carried the balanced translocation; the father had a normal karyotype. Amniotic fluid alpha-fetoprotein level was elevated and an acetylcholinesterase band was detected. Level II ultrasonography at 17 and 24 weeks revealed several abnormalities, including a large facial cleft and a probable facial teratoma and intracranial tumor. Autopsy following pregnancy termination confirmed the presence of both. Chromosome evaluation of 172 metaphases of both the epignathus and the intracranial teratoma demonstrated a predominance of the cell line with 47 chromosomes (166/172 = 96.5%), while from nonteratoma tissue (lung, liver, skin, and brain) only the balanced karyotype was detected. These observations suggest that the chromosomal imbalance is instrumental in the etiology of the teratoma.

Abnormalities, Multiple↗
PubMed1992

Cytomegalovirus infection, fetal liver disease, and neonatal hemochromatosis.

Neonatal hemochromatosis is an uncommon disorder, clinicopathologically defined by severe and generally fatal liver disease of intrauterine onset associated with extrahepatic siderosis that spares reticuloendothelial elements (hemochromatotic siderosis). The agent or agents of liver disease in neonatal hemochromatosis are not known. It also is not known if intrauterine liver disease of defined infective etiology can lead to hemochromatotic siderosis. We present two patients with fetal liver disease and hemochromatotic siderosis whose cases help address these points. In the first patient rare hepatobiliary and numerous renal tubular cytomegalovirus (CMV) inclusions were found; CMV infection was confirmed by the polymerase chain reaction. Studies of the mother of the second patient 1, 5, and 9 weeks post-partum showed recent seroconversion against CMV; seroconversion against other infectious agents (toxoplasma, rubella, herpes, parvovirus B19, hepatitis A/B/C) was not present. Histologic, immunohistochemical, in situ hybridization, or polymerase chain reaction evidence of CMV infection was not present in infant tissues, even though peripartum maternal seroconversion against CMV was observed. We conclude that hemochromatotic siderosis may accompany chronic fetal liver disease of defined infective etiology (patient no. 1) and that recent maternal seroconversion against CMV in the presence of severe fetal liver disease does not necessarily mean that transplacentally acquired CMV infection caused the fetal liver disease (patient no. 2). Polymerase chain reaction documentation of infective-agent genomic sequences in fetal or infant tissues permits more accurate interpretation of maternal serologic data.

Adolescent↗
PubMed1992

Disordered pathways of fibrin turnover in lung lavage of premature infants with respiratory distress syndrome.

Premature infants who have self-limited respiratory distress syndrome (RDS) rapidly improve, whereas infants with a complicated respiratory course are more likely to develop bronchopulmonary dysplasia (BPD), a chronic lung disorder that is the result of prolonged lung injury and impaired healing. The balance of competing activities of coagulation and fibrinolysis may contribute to the premature lung's response to acute injury and determine, in part, whether there is early resolution or protracted alveolar inflammation. To determine the relative activities of the coagulation and fibrinolytic pathways in neonatal lung injury, procoagulant (PC) and plasminogen activator (PA) activities were measured in undiluted cell-free lung lavage samples obtained serially over the first 28 days of life from 11 infants with self-limited RDS, 11 infants with evolving BPD, and 5 mechanically ventilated control infants without lung disease. Lung lavage from all three groups contained readily detectable procoagulant activity due mainly to the tissue factor-Factor VII complex. Plasminogen activator activity was relatively high in control lavage samples but depressed on the first day of life in the two groups of infants with lung disease: median, 0.3814 IU/ml (control); 0.0541 IU/ml (RDS); and 0.0454 IU/ml (BPD), p < 0.05 in each case compared with control. Two infants with severe lung disease had no detectable plasminogen activator activity in lung lavage on the first day of life. Depressed fibrinolytic activity correlated with severity of lung disease assessed radiographically and by pulmonary function measurements. Plasminogen activator activity was due to both tissue plasminogen activator and urokinase.(ABSTRACT TRUNCATED AT 250 WORDS)

Apgar Score↗
PubMed1991

Alimentary duplication presenting as an hepatic cyst in a neonate.

A large hepatic cyst was excised from an infant who presented on the first day of life with an abdominal mass. Intraoperative, gross, and microscopic observations indicated that this was a cystic duplication of the ileum that extended into the liver. The cyst had a gastric mucosal lining, and there was evidence of ulceration. The occurrence of an alimentary duplication within the liver has been described in only one previous report.

Cysts↗
PubMed1991

[Comparison of central effects produced by intracerebral injection of glutamic acid, quisqualic acid, and kainic acid].

Icv glutamic acid (Glu), quisqualic acid (QA) and kainic acid (KA) significantly increased spontaneous activity of mice in photecell box, and induced dose-dependent rise of blood pressure in anesthetized rats. Their intensities were arranged in the order of KA greater than Glu greater than QA. In mice step-through test Glu 0.1 micrograms icv improved learning and memory; KA 1 ng had no evident effect; and QA 0.1 microgram impaired learning and memory, which were also confirmed by step-down test in normal mice. Therefore, the non-NMDA (N-methyl-D-aspartate) receptor subtype might be different from the NMDA receptor subtype in the action of learning and memory.

Animals↗