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R J Chen

Publications and source records attributed to R J Chen.

At least 55 records · Page 3Linked to original sources
PubMed1998

Hepatocellular carcinoma presenting as jaundice, hemobilia, and acute pancreatitis: a case report.

A 48-year-old asymptomatic male hepatitis B virus carrier presented with a 2-day history of fever, chills, right upper quadrant abdominal pain, and jaundice. Shock was detected on admission. Emergency abdominal computed tomography (CT) scanning without contrast enhancement showed the features of acute pancreatitis. Hemobilia, edematous pancreatitis, cholestasis and cholecystitis were found on exploratory laparotomy. Neither stone nor active bleeding were detected on intraoperative choledochoscopic examination. Postoperative T-tube cholangiography one month later revealed non-opacification of the left intrahepatic duct. The patient's abdominal pain and hemobilia recurred. Celiac angiography and CT scanning with contrast showed two hepatocellular carcinomas (HCC) in the left lobe of the liver. This is the first case report in the English literature of HCC presenting as jaundice, hemobilia, and acute pancreatitis.

Acute Disease↗
PubMed1998

Traumatic thoracic aortic injury caused by a sharp edge of left fractured rib on body position change: case report.

Aortic injury caused by penetration of a fractured rib is very rare. We present a patient with aortic injury demonstrated using serial imaging studies. A 66-year-old woman fell from a ladder and sustained multiple left-side rib fractures. There was a small left hemothorax and widened mediastinum on the initial chest roentgenogram in the emergency department. Chest computed tomography (CT) revealed a posterior segmental fracture of the sixth rib on the left side with a sharp edge penetrating into the posterior aspect of the thoracic aorta. It was initially missed. More than 1000 cc of fresh blood suddenly gushed out of the chest tube 7 hours after the traumatic event. After resuscitation, an aortogram was performed which showed blood extravasation from the thoracic aorta at the rib fracture site. Unfortunately, surgical intervention was delayed and she died. Early detection and early surgical intervention are necessary in patients with a widened mediastinum and positive results on imaging studies.

Aged↗
PubMed1997

Multiple kinesin family members expressed in teleost retina and RPE include a novel C-terminal kinesin.

Kinesins comprise a large superfamily of microtubule-based motor proteins, individual members of which mediate specific types of motile processes. To identify kinesin family members (KIFs) that are critical to retinal function and thus to vision, a reverse transcriptase polymerase chain reaction (RT-PCR) cloning strategy was used to isolate putative KIFs expressed in the neural retina and retinal pigmented epithelium (RPE) of the striped bass, Morone saxatilus. Eleven fish KIFs (FKIFs) were isolated from neural retina and six of the same FKIFs were also isolated from RPE. One of the KIFs identified in this screen, FKIF2, was the most prevalent clone detected both in the retina (41% of clones) and RPE (72% of clones). Based on predicted amino acid sequence homology within the motor domain, seven of the FKIFs have been tentatively assigned to known kinesin families: the kinesin heavy chain family (FKIF1, 5 and 9), the unc104/KIF1 family (FKIF3 and 8), the KIF2 family (FKIF4), and the cKIF family (FKIF2). Northern blot analysis revealed that each detectable FKIF exhibited a unique tissue-specific expression pattern. Since FKIF2 was more highly expressed in retina than in any other tissue tested, including brain, and was the most abundant KIF message expressed in both retina and RPE, it was examined in more detail and the complete approximately 2.3 kb open reading frame for FKIF2 was cloned and sequenced. The predicted amino acid sequence indicates that FKIF2 has a C-terminal motor domain, and thus is a member of the cKIF family. FKIF2 is only 36.5% identical at the amino acid level to the most closely related cKIF in the database, suggesting that FKIF2 may be a novel member of this family. Antibodies raised against a unique peptide specific to FKIF2 recognize an approximately 80 kd protein in homogenates of retina, RPE, brain and kidney. The pronounced expression of FKIF2 in retina and RPE suggests that FKIF2 may play an important role in microtubule-dependent motile events in these two tissues.

Amino Acid Sequence↗
PubMed1997

Molecular cloning and analysis of a HSP (heat shock protein)-like 42 kDa antigen gene of Mycoplasma hyopneumoniae.

The recombinant clone expressing the 42 kDa protein (P42) of Mycoplasma hyopneumoniae in Escherichia coli was analyzed. The 4.4 kb HindIII-Xmal DNA fragment expressing the p42 gene product encodes three ORFs: p42 and p16 in the forwarding strand, p24 in the reverse strand. Sequence comparisons revealed that p42 could be part of a p65 gene, and has 62% identities with Mycoplasma genitalium HSP70 gene and 56% identities with Bacillus subtilis dnaK gene; p16 and p24 genes share 73% and 47% identities with Erysipelothrix rhusiopathiae dnaJ gene and Pseudomonas fluorescens uvrC gene, respectively. Further analysis demonstrated that P42 is indeed a heat shock protein and the monospecific antibodies against P42 can block the growth of Mycoplasma hyopneumoniae.

Amino Acid Sequence↗
PubMed1997

Isolated common iliac artery occlusion secondary to atherosclerotic plaque rupture from blunt abdominal trauma: case report and review of the literature.

Traumatic isolated common iliac artery occlusion is unusual. Only rare cases of common iliac arterial injuries resulting from blunt abdominal trauma have been reported, and most of them were attributed to the seat-belt syndrome and associated with visceral organ perforation or pelvic fracture. We reported an unusual isolated common iliac artery occlusion secondary to atherosclerotic plaque rupture from blunt abdominal compressive trauma without other visceral injury. This case presented with acute limb ischemia and paralysis that was successfully treated by thromboendarterectomy. The symptoms and signs, surgical modalities, and associated injuries were reported and the literature was also reviewed.

Arterial Occlusive Diseases↗
PubMed1997

Prevalence of single and multiple infection with human papillomaviruses in various grades of cervical neoplasia.

Evaluation of human papillomavirus (HPV) diversity in various grades of cervical lesions is helpful for understanding the characteristics of HPV infection in the pathogenesis of cervical neoplasia. A total of 227 women with normal cervices (n = 72), low- and high-grade cervical squamous intraepithelial lesions (SILs) (n = 55 and 53, respectively) and cervical carcinomas (n = 47) were screened for human papillomavirus (HPV) types 6, 11, 16 and 18 infection by the polymerase chain reaction. The prevalence of multiple HPV infections in patients with normal cervices, low-grade SILs, high-grade SILs and cervical carcinomas was 22.2%, 61.8%, 41.5% and 21.3%, respectively, while the prevalence of a single-type infection was 36.1%, 21.8%, 30.2% and 61.7%, respectively. HPV 16/11 and 16/18 were the most common combinations observed in multiple infections. Multiple HPV infections were seen most frequently in patients with low-grade SILs, and the prevalence decreased with increasing severity of cervical neoplasia. In contrast, infection with a single HPV type was most commonly observed in patients with cervical carcinoma, and the prevalence decreased with decreasing severity of cervical neoplasia. HPV 16 was the predominant single-type infection in patients with cervical carcinoma and this prevalence decreased steadily with decreasing severity of cervical neoplasia. Conversely, HPV 11 was the predominant single-type infection in patients with normal cervices. This prevalence decreased with increasing severity of cervical neoplasia. Patients with low-grade SILs had a higher prevalence of HPVs, regardless of single or multiple infection status, and larger copy numbers of virus genome were seen more frequently in patients with more severe lesions.

Adolescent↗
PubMed1997

Effectiveness of quinolone antibiotics in modulating the effects of antifungal drugs.

Quinolone antibacterial drugs inhibit DNA gyrase, a type 2 topoisomerase. Since topoisomerases are present in eukaryotic cells, it was of interest to evaluate the antifungal activities of two clinically available quinolones, ciprofloxacin and trovafloxacin, alone and in combination with amphotericin B or fluconazole, in vitro against Candida albicans and in a murine model of invasive candidiasis. The in vitro activity of trovafloxacin was also tested against other yeasts and molds. In vitro, trovafloxacin exhibited no antifungal activity against any of the fungi (MIC, >250 microg/ml). There was also no effect of the quinolone on the in vitro activity of either antifungal drug. Marked antifungal effects were seen, however, in the murine model of candidiasis. In all experiments, control mice infected intravenously with C. albicans were dead by day 24. While either quinolone had minimal effects on survival of mice when used alone in oral doses of up to 40 mg/kg twice daily, the combination of the quinolone with fluconazole (40 or 80 mg/kg given twice daily by oral gavage) was more effective in prolonging survival than was fluconazole alone. Colony counts of kidneys on days 12 and 30 showed similar reductions in C. albicans recovered from mice treated with fluconazole with or without trovafloxacin or amphotericin B with or without trovafloxacin. Survival of mice treated with a suboptimal dose of amphotericin B (0.2 mg/kg/day) was also improved when trovafloxacin (40 mg/kg) given twice daily was included (0 versus 27%, respectively; P < 0.05). While the mechanisms of action of the combination of trovafloxacin and amphotericin B or fluconazole are unclear, further work focused on fungal topoisomerase inhibition and the mechanism of the antifungal effect of quinolone antibacterial drugs is warranted.

Amphotericin B↗
PubMed1997

Light-induced fluorescence spectroscopy to differentiate benign and malignant uterine cervical lesions.

In Taiwan, cervical cancer is the leading malignancy among women. For the early detection of cervical neoplasia, light-induced fluorescence spectroscopy was conducted ex vivo to assess the ability of this technique to differentiate cervical neoplastic tissue (20 samples) from normal or inflammatory cervical tissue (37 samples) at an excitation wavelength of 280 nm. The principal fluorescent peaks occurred within +/- 5 nm of 330 nm and 470 nm emission. At 330 nm emission, the spectrum of the normal or inflammatory tissue was significantly stronger than that of the neoplastic tissue after are normalization. However, at 470 nm emission, the spectrum of the normal or inflammatory tissue was significantly weaker than that of the neoplastic tissue. A diagnostic algorithm based on the ratio of relative intensities of 330 nm to 470 nm emission within the 5 +/- nm peak area of each sample was calculated and paired. The ratios showed that histologically neoplastic lesions could be distinguished from inflammatory samples using a 280-nm-excitation wavelength with a sensitivity, specificity and positive predictive value of 94%, 82% and 73%, respectively. The average ratio of malignant or dysplastic cervical samples was significantly greater than that of the inflammatory samples (p < 0.001). Our ex vivo study indicated that light-induced fluorescence spectroscopy may be useful in differentiating malignant or premalignant from normal or inflammatory cervical tissue.

Algorithms↗
PubMed1996

Prediction of residual neoplasia based on histopathology and margin status of conization specimens.

OBJECTIVE: To evaluate the status of cone margins and the severity of cervical neoplasia as predictors of residual lesions in the remaining cervices. METHODS: We performed a 7-year retrospective study and reviewed 172 patients who had undergone cervical conization followed by subsequent hysterectomy. Pathological findings of the cone margins and residual lesions in the postcone hysterectomy specimens were recorded for analysis. RESULTS: The prevalence rates of positive cone margins were 0, 18.6, 23.8, and 25%, respectively, in patients with low-grade squamous intraepithelial lesion (SIL) (n = 6), high-grade SIL (n = 129), stage IA1 cervical cancer (CC-IA1) (n = 21), and CC-IA2 (n = 16). The prevalence rates of positive residual lesions in postcone hysterectomy specimens were 0, 23.3, 23.8, and 43.8%, respectively, in those with low-grade SIL, high-grade SIL, CC-IA1, and CC-IA2. Residual lesions were significantly more frequently found in patients with positive cone margins (84.8%) than in those with negative margins (10.1%) (X2 = 76.81, P < 0.0001). All six patients with low-grade SIL had free cone margins. Positive predictive values of margin status for the presence of residual lesions were 83.3, 80, and 100%, respectively, in patients with high-grade SIL, CC-IA1, and CC-IA2. Only two (6.1%) of 33 patients with positive cone margins had more advanced residual lesions. Negative predictive values of margin status for the absence of residual lesions were 100, 90.5, 93.8, and 75%, respectively, in patients with low-grade SIL, high-grade SIL, CC-IA1, and CC-IA2. None of the 139 patients with negative margins had invasive residual lesion. CONCLUSIONS: (1) The prevalence of positive cone margin and residual lesion increased with higher severity of cervical neoplasia. (2) Patients with positive cone margins had significantly higher chances of having residual lesion than those with negative margins. (3) Free cone margin does not ensure the absence of residual lesion in the remaining cervix. However, the possibility of residual invasive cancer in the remaining cervix is remote. (4) Positive cone margin does not invariably indicate the presence and persistence of more severe residual lesion. Subsequent hysterectomy may be reserved for the patient with invasive cone pathology, the patient with concomitant morbid uterine condition, or the patient who is not reliable for continuous follow-up.

Conization↗
PubMed1996

Malignant ovarian germ cell tumors.

OBJECTIVES: Fifty patients with malignant ovarian germ cell tumors, which accounts for 10.8% of all ovarian malignancies, were treated from 1977 through 1994. Their cases are reviewed. METHODS: The histology includes endodermal sinus tumor (EST) in 15 patients, immature teratoma in 14, dysgerminoma in 13, and mixed germ cell tumor in eight. The mean age at presentation was 21.5 years and mean primary tumor diameter was 16 cm. All patients underwent surgery as the initial treatment, and 10 received more than one operation. Postoperative adjuvant chemotherapy was not given to cases with stage Ia immature teratoma and dysgerminoma. VAC (vincristine, actinomycin D, cyclophosphamide) and BVP (bleomycin, vinblastine, cisplatin) regimens were utilized in early 1980s for EST and advanced-stage tumors of immature teratoma and dysgerminoma. BEP (bleomycin, etoposide, cisplatin) and EP (etoposide, cisplatin) regimens were applied in advanced-stage disease and some stage I disease since 1990. VIP (VP-16, ifosfamide, cisplatin) regimen was employed as salvage regimen in cases where other combinations failed. RESULTS: alpha-Fetoprotein (AFP) was elevated in every tumor containing endodermal sinus element, and AFP served as a good indicator for prediction of tumor recurrence. The follow-up time ranged from 5 to 144 months with the mean of 54.5 months. CONCLUSIONS: The survival rate for EST was 54%, that for immature teratoma and dysgerminoma was 85% and 90%, respectively.

Adolescent↗
PubMed1996

Spontaneous rupture of left external iliac vein: case report and review of the literature.

Iliac vein rupture is rare and primarily results from major trauma or occurs during pelvic surgery. Spontaneous nontraumatic rupture is even more unusual, with only 14 cases reported in the literature. We report an additional case, summarize all of the cases, and discuss the possible causes and treatment of iliac vein rupture and the role of anticoagulants in postoperative management.

Aged↗
PubMed1996

Triplet pregnancy complicated by intrauterine fetal death of conjoined twins from an umbilical cord accident of an acardius. A case report.

BACKGROUND: Acardius is a rare occurrence in monozygotic multiple pregnancies. Triplet pregnancy composed of an acardiac fetus and a pair of conjoined twins is even more rare. The outcome of the acardius is invariably fatal, and the mortality rate of the other fetuses ranges between 50% and 70%. Perinatal mortality results mainly from complications of twin-twin transfusion syndrome. CASE: Intrauterine fetal death, caused by an umbilical cord accident, with twisting of the acardius's cord around the fused cords of conjoined twins is reported in this present work. CONCLUSION: An acardius should be thoroughly sought when monochorionic multiple pregnancies are found by ultrasound during prenatal care. The complications of pregnancy caused by an acardiac fetus can be avoided by using proper management.

Adult↗
PubMed1996

Mature cystic teratoma of the ovary: a clinicopathologic study of 283 cases.

BACKGROUND: Although in the English literature, much has been published about ovarian teratoma, no large series has been reported in Taiwan. Therefore a retrospective study of 283 consecutive cases of mature cystic teratomas of the ovary, operated at National Taiwan University Hospital between 1988 and 1993, was undertaken. METHODS: This series was based on a retrospective chart study at the Department of Obstetrics and Gynecology of the National Taiwan University Hospital from 1988 to 1993. All cases included in this study were proven by pathology review. The clinical data, pathology and complications are summarized. RESULTS: The incidence of mature cystic teratoma was 32.6% of primary ovarian neoplasm. As for the age distribution, the youngest patient was 12 years old and the oldest, 76. The largest number of cases was found in patients between the ages of 20 and 30 years; the mean age was 35.4 years. Pain, the most common complaint, was noted in 48.1% of the cases in whom it varied from a dull ache to the sharp, stabbing pain of torsion. Of greater interest was an unexpectedly high incidence (16.6%) of asymptomatic cysts found on routine physical examination. The right ovary was involved in 51.2%, the left ovary in 40.6% and bilateral ovaries were involved in 8.2%. The incidence of torsion was 9.2%, and was the highest in all complications. Ten concurrent pregnancies were noted, an incidence of 3.5%. The incidence of malignant transformation was 0.7%, with a pathology of squamous cell carcinoma. CONCLUSIONS: Mature cystic teratom is the most common germ cell tumor and accounts for about 33% of all ovarian neoplasm They occur primarily during the reproductive years, but may occur in the postmenopausal period or in childhood. A cystic teratoma can undergo malignant transformation; it occurs most frequently in postmenopausal women, and the prognosis is poor. However, it is a rare complicaiton, with an incidence less than 1%.

Adolescent↗
PubMed1996

The suitable treatment for adenocarcinoma in situ of uterine cervix: a report of four cases.

Adenocarcinoma in situ (AIS) of the uterine cervix is a rare disease. Some authors suggested that conization is a suitable treatment for AIS as for squamous cell carcinoma in situ. However, others did not agree. Four cases of AIS, from 1984 to 1994, have been diagnosed in the Hospital of National Taiwan University. If the diagnosis of the conization specimen showed AIS, abdominal total hysterectomy was performed days thereafter. The remaining uterine cervix was checked by histopathology to determine whether it was free of cancer lesions. AIS lesions remained in the uterine cervix, as shown by conization in two cases. AIS is not like lesion as squamous cell carcinoma in situ lesion which is easy to be removed by conization. It is suggested that conization is not an adequate treatment for AIS, rather, a total hysterectomy should be performed.

Adenocarcinoma↗
PubMed1995

Independent clinical factors which correlate with failures in diagnosing early cervical cancer.

Our aim was to identify independent factors that correlated with colposcopically directed biopsy's reliability as a method for diagnosing early cervical cancer. One hundred ninety-one of a total of 2265 patients who had colposcopic examinations because of abnormal Papanicolaou smears were included in this study. These patients had all undergone a hysterectomy after being diagnosed as having cervical intraepithelial neoplasia grade III by colposcopically directed biopsy. By univariate analysis, old age (P = 0.0195), achievement of menopausal status (P = 0.0046), large lesion size (P = 0.0021), and unsatisfactory colposcopy (P = 0.0017) were found to be associated with the nondiagnosis of early cervical cancer. However, multivariate analysis using stepwise logistic regression revealed that large lesion size (P = 0.003) and unsatisfactory colposcopy (P = 0.0008) were the only independent factors that correlated with nondiagnosis. Our findings indicate that in order to reach a clear-cut diagnosis, cases with either unsatisfactory colposcopy or satisfactory colposcopy with large lesions (despite a lack of histologic evidence of invasions) should undergo a diagnostic conization.

Adult↗
PubMed1995

Surgical management of juxtahepatic venous injuries in blunt hepatic trauma.

The purpose of this analysis was to understand better the problems faced in the management of blunt juxtahepatic venous injuries and to try and simplify the controversies regarding the optimal surgical approach to these injuries. Charts of 92 blunt liver trauma patients treated between July 1, 1991 to June 30, 1993 were reviewed. Nineteen patients with blunt juxtahepatic venous injuries were identified. The isolated left hepatic vein injury group (five patients) were all treated using a nonshunting approach with no mortalities. Half of the isolated right hepatic vein injury group (ten patients) received an atriocaval shunt, and the other half did not. These two different approaches each produced one survivor, with a combined mortality rate of 80% (eight of ten patients). One of the combined injuries group (four patients) received a total hepatectomy followed by liver transplantation. Another received a shunt. The other two were treated without shunting, but all of them expired. The overall mortality rate was 63.2% (12 of 19 patients), with nine patients dying intraoperatively or immediately postoperatively from exsanguination. The other three died 10, 25, and 30 days postoperatively because of sepsis. Juxtahepatic venous injury should be suspected after failure of the Pringle maneuver to stop bleeding and the different venous injuries differentiated by palpation of the adjacent hepatic parenchymal injuries. If an isolated left hepatic vein injury is found and the liver parenchymal injury is limited to segments II, III, or IV, then a nonshunting approach will achieve the optimal outcome.

Adolescent↗