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H C Hsu

Publications and source records attributed to H C Hsu.

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

Physiological elongation of ligamentous complex surrounding the hindfoot joints: in vitro biomechanical study.

Ligaments surrounding the hindfoot joints play an important role in hindfoot stability. This in vitro study investigated anatomical and biomechanical characteristics of nine major ligamentous structures, including length and orientation at neutral position and physiological elongation with the foot in five different positions relative to the neutral position. The results showed that ligament elongation depended on the ligament length, orientation in neutral position, and movement of bones to which they were attached.

Aged↗
PubMed1997

Dominant negative activity of mutant thyroid hormone alpha1 receptors from patients with hepatocellular carcinoma.

Complementary DNAs for two mutant thyroid hormone alpha1 receptors (TR alpha1) were isolated from hepatocellular carcinomas of two patients. Sequence analyses of the complementary DNAs showed a single Val390Ala and double Pro398Ser/Glu350Lys mutations in mutants H and L, respectively. We characterized their hormone-binding, DNA-binding, and dominant negative activities. Mutants H and L did not bind the hormone T3. Their DNA-binding activities were analyzed using three types of thyroid hormone response elements (TREs) in which the half-site binding motifs are arranged in an everted repeat (Lys), an inverted repeat (Pal), or a direct repeat separated by four nucleotides (DR4). Compared with wild-type TR alpha1 (w-TR alpha1), which bound these TREs with different homodimer/monomer ratios, binding of mutant L to the three TREs as homodimers was reduced by approximately 90%. However, binding of mutant H to these TREs was more complex. Although it bound normally to DR4 as homodimers, its binding to Lys as homodimers was reduced by approximately 80%. Surprisingly, its binding to Pal was markedly enhanced compared with w-TR alpha1. The binding of these two mutants to the three TREs as heterodimers with retinoid X receptors (RXR alpha and -beta) was not significantly affected. Consistent with the lack of T3-binding activity, both mutants had lost their trans-activation capacity. Mutants H and L exhibited dominant negative activity, but differed in their TRE dependency. The dominant negative potency of mutant H was in the rank order of Pal > DR4 > Lys, whereas no TRE dependency was observed for mutant L. The present study indicates that mutations of the TR alpha gene do occur in patients and that these novel TR alpha1 mutants provide a valuable tool to further understand the molecular basis of the dominant negative action of mutant TRs.

Base Sequence↗
PubMed1997

Autopsy findings on patients with AIDS in Taiwan.

At National Taiwan University Hospital, from 1986 to 1996, autopsies were performed on 16 patients with acquired immunodeficiency syndrome. There were 15 men and 1 woman. Fourteen of these male patients had contracted the disease as a result of sexual practice, among which 9 were homosexual, 1 was bisexual and 4 were heterosexual. One of the patients had become infected by sharing a syringe during intravenous drug use. The female was a sex worker. Among these patients, only 2 had been tested for HIV before developing AIDS. On autopsy, lymphoid depletion and thymus atrophy were found in all patients. Testicular atrophy was noted in all the male patients. Three patients died of malignant lymphoma. Twelve patients died of opportunistic infections and 1 committed suicide. The initial opportunistic infection was usually oral candidiasis. Pneumocystis carinii pneumonia (PCP) was the most common opportunistic infection developed in the early stage while cytomegalovirus (CMV) infection was the most common one found in the late stage. Mycobacterium infection had developed in 8 patients. Six patients had disseminated Kaposi's sarcoma (KS) and 4 of them were homosexual. In 4 patients, biopsy specimens were proved to have KS associated viral (HHV-8) genome. Malignant lymphoma was found in 4 cases, all were of high grade B cell type. Epstein-Barr virus (EBV) encoding small RNA (EBER1) was demonstrated in all the lymphomas. In conclusion, (1) the prevalence of tuberculosis (38%) in patients with AIDS in Taiwan is high; (2) the most common opportunistic infections in this series are candidiasis, PCP and CMV infections; (3) the incidence of AIDS related non-Hodgkin's lymphoma in Taiwan has increased since 1995.

AIDS-Related Opportunistic Infections↗
PubMed1997

Immunohistochemical analyses of p53 protein expression in breast cancers in Taiwan: a clinicopathologic study.

Immunohistochemical analysis of the p53 protein was performed on paraffin sections of tumor tissue from 210 breast cancer patients. All patients had a follow-up period of more than 5 years. Protein expression of p53 was detected in 64 patients (30.5%). There was significant correlation between p53 protein expression and a high histologic grade (grade II vs grade I/II, 49% vs 23.6%, p = 0.0008) and high mitotic index (> or = 10/10 hpf vs < 10/10 hpf, 42.9% vs 19.6%, p = 0.0004), but not with axillary node status, stromal lymphocytic infiltration, or estrogen receptor or progesterone receptor status. We found that p53 protein expression was not a significant factor in predicting 5-year mortality.

Adult↗
PubMed1997

The double-blind test of sodium hyaluronate (ARTZ) on osteoarthritis knee.

BACKGROUND: At this time, no definite treatment exists for osteoarthritis disease. Hyaluronate (ARTZ) is one of the most important components of synovial fluid. It is generally accepted that hyaluronic acid protects the articular cartilage and soft tissue surfaces from trauma during joint function. METHODS: Ninety patients with 116 knees diagnosed as early arthritis (mild to moderate) by four senior orthopaedic surgeons were selected to join this study. The trial design was applied with a double-blind model. The selected patients were randomly injected with 2.5 ml drugs (ARTZ or placebo) intra-articularly once a week for five consecutive weeks without the use of local anesthetic drugs. Evaluation results included grading of subjective and objective symptoms and daily activities. The follow-up period was up to six months after initial injection. RESULTS: According to the results of clinical evaluation and statistical analysis, SPH (ARTZ) is quite effective for osteoarthritis knees, and significantly better than the placebo. The effective peak was one week after five injections of ARTZ. The effective period could last up to three months without additional treatment. The efficacy of ARTZ on osteoarthritis knees was more prominent for relief of motion pain and improvement of knee movement. No side effects developed during a six month period. CONCLUSIONS: Based on clinical results here, SPH is a safe drug for administration as an alternative approach to treat the osteoarthritis knee.

Activities of Daily Living↗
PubMed1997

Leiomyosarcoma of the left atrium: a case report.

Primary malignant cardiac tumors are uncommon, and cardiac leiomyosarcoma is extremely rare. We reported a case of left atrial (LA) leiomyosarcoma with unusual clinical manifestations. A 28-year-old female presented with unknown cause of fever, body weight loss and anemia for two months. Echocardiography and magnetic resonance image study disclosed a 5 x 3 x 3.6 cm3 lobulated mass in the LA with invasion to its posterior wall. Histologic and immuno-histochemical studies of the resected specimen revealed a picture of leiomyosarcoma. The patient improved after surgical resection and post-operative chemotherapy. The literature was reviewed with a discussion of the clinical manifestations, diagnosis and treatment strategy of this rare tumor. Diagnosis of LA leiomyosarcoma is frequently delayed to make a very poor prognosis. Postoperative chemotherapy should be considered because of highly possible incomplete resection. However, an optimal treatment regimen remains unknown.

Adult↗
PubMed1997

Detection of hepatic neoplasms by computed tomographic arterial portography in cirrhotic patients.

Computed tomography (CT) during arterial portography (CTAP) is useful in detecting hepatic tumors but cirrhotic change may interfere with portal flow and the prediction of resectability. We evaluated the usefulness of CTAP in detecting hepatic tumors, especially hepatocellular carcinoma (HCC), in patients with or without cirrhotic change. Ninety-six patients with pathologically proven hepatic tumors were assessed, of whom 90 had hepatocellular carcinoma. The tumors had been previously detected by abdominal ultrasound and CT scans, after which the patients were referred for angiography and CTAP. The CTAP findings were compared with ultrasonographic, conventional CT, angiographic, and subsequent surgical and pathologic findings regarding size, number, and location of the hepatic lesions. CTAP detected 134 of 143 pathologically proven lesions. The overall sensitivity of CTAP in the 96 patients was 94%, with a false-positive rate of 22%. The detection rate of CTAP for tumors less than 2 cm in diameter was high (92%). The sensitivity and false-positive rate for CTAP in 60 cirrhotic patients were 94% and 23%, respectively, CTAP is a sensitive imaging modality for detection of hepatic neoplasms even in patients with cirrhosis, but its false-positive rate is high.

Adult↗
PubMed1997

Retinoic acid syndrome: a case report.

All-trans-retinoic acid (ATRA) is a differentiation agent which can induce complete remission in a majority of patients with acute promyelocytic leukemia (APL). Unfortunately, about one-fourth of patients thus treated may develop potentially fatal complications, including respiratory distress, fever, pericardial and pleural effusion, renal failure and hypotension which constitute the retinoic acid syndrome (RA syndrome). We report one APL patient, who presented with leukocytosis and subacute disseminated intravascular coagulopathy, and developed RA syndrome during treatment with ATRA.

Adult↗
PubMed1996

Long-term outcome after surgery for asymptomatic small hepatocellular carcinoma.

The subjects of this study were 48 asymptomatic patients who had surgery for small hepatocellar carcinoma (HCC). There were 42 men and six women with mean (s.d.) tumour size of 3.31 (1.46) cm and age 55.0 (7.4) years. Follow-up was for a minimum of 10 years. The main concern of this study was a univariate analysis of factors that might affect long-term survival after surgery, which was 50 per cent at 5 years and 31 per cent at 10 years. A high incidence of recurrent HCC (37 of 48 patients) was observed but reoperation further prolonged life in some cases. The significant prognostic factors detected by multivariate analysis were: histological classification, functional liver reserve and histology of the resection margin. Tumour size, gross appearance of tumour, presence of liver cirrhosis, serum alpha-fetoprotein level, age or sex did not affect the prognosis.

Carcinoma, Hepatocellular↗
PubMed1996

Expression in human endothelial cells of ADP-ribosylation factors, 20-kDa guanine nucleotide-binding proteins involved in the initiation of vesicular transport.

ADP-ribosylation factors (ARFs) are approximately 20-kDa, guanine nucleotide-binding proteins, initially discovered as stimulators of cholera toxin ADP-ribosyltransferase activity and subsequently shown to participate in vesicular trafficking. Five of the six mammalian ARFs have been identified in human tissues by molecular cloning. They fall into three classes (class I: ARFs 1-3; class II: ARFs 4, 5; class III: ARF 6) based on deduced amino acid sequence, size, phylogenetic analysis, and gene structure. Similar to the rab family of approximately 20 kDa guanine nucleotide-binding proteins, the ARFs appear to function in specific trafficking pathways. The presence of a specific ARF might serve as a marker for that pathway. To verify expression of ARF mRNA and protein in human umbilical vein endothelial cells, immunoreactivity using antibodies specific for each ARF class, quantitative polymerase chain reaction (PCR) using ARF-specific, internal cRNA standards containing unique restriction enzyme cleavage sites introduced by point mutations, and Northern analysis with probes specific for ARFs 1, and 3-6, were utilized. PCR and Northern analysis were in agreement in showing that amounts of mRNA for ARF 1 and ARF 4 were similar and higher than those of ARF 3 and ARF 5 which were greater than ARF 6. Primarily, Class 1 ARF proteins were detected by immunoreactivity, with the majority in the supernatant fraction. The relative expression of ARFs in endothelial cells thus differs from that in neuronal tissues where it had been found that ARF3 is the predominant species.

ADP-Ribosylation Factor 6↗
PubMed1996

Chronic hepatitis C without anti-hepatitis C antibodies by second-generation assay. A clinicopathologic study and demonstration of the usefulness of a third-generation assay.

To study the clinicopathologic features of hepatitis C viremic patients negative for hepatitis C antibodies (anti-HCV) by current second-generation assay, we categorized 139 consecutive histologically verified patients with chronic non-A, non-B hepatitis into three groups: 121 (87%) were positive for second-generation anti-HCV (group A); 10 (7%) were negative for second-generation anti-HCV but positive for HCV RNA (group B); and 8 (6%) were negative for both antibodies and viremia (group C). Six (60%) of group B patients could be, further detected by a new third-generation assay, but none of group C patients was third-generation anti-HCV-positive. The demographic features, mean peak serum alanine aminotransferase levels, HCV genotype distribution, and histologic changes were comparable among the three groups. The study indicates that most patients with chronic hepatitis C in Taiwan could be identified by current second-generation assay, and viremic but antibody seronegative patients were clinicopathologically similar to the seropositives. Most patients of the latter group could be diagnosed by a third-generation assay, indicating the usefulness of this assay.

Chronic Disease↗
PubMed1996

Surgical resection for recurrent hepatocellular carcinoma: prognosis and analysis of risk factors.

BACKGROUND: Hepatocellular carcinoma (HCC) is common in Asian countries, and tumor recurrence is the most common cause of treatment failure after curative resection. Repeated hepatectomy is performed only for selected patients because most patients with HCC also have liver cirrhosis and poor liver function reserve. The purposes of this study were to clarify the outcome of the patients after second hepatectomy for recurrent HCC and to evaluate the prognostic factors after second hepatectomy. METHODS: We used retrospective cohort study to examine the disease-free survival, cumulative survival, and possible prognostic factors for recurrence and death in 59 patients who underwent surgical resection for recurrent HCC at the National Taiwan University Hospital from August 1986 to December 1993. Another 64 patients with unresectable recurrent HCC were used as a historical control group. The survival curves between those patients with resectable HCC and those with unresectable HCC were compared. RESULTS: After resection for recurrent HCC, gender and multiplicity (n > 3) of tumor affect recurrence rate (p = 0.046 and 0.021, respectively), whereas gender, age, and tumor invasiveness affect survival rate significantly (p = 0.024, 0.021, and 0.046, respectively). The survival rate of patients with resectable HCC was significantly better than that of those with unresectable HCC. CONCLUSIONS: For recurrent HCC surgical resection is an effective mode of treatment in selected patients. Whether surgery is better than other modes of treatment in the treatment of resectable recurrent HCC demands further investigation.

Adult↗
PubMed1996

Expression of Epstein-Barr virus in carcinomas of major salivary glands: a strong association with lymphoepithelioma-like carcinoma.

To elucidate the role of Epstein-Barr virus (EBV) in salivary gland carcinomas, 56 cases of carcinomas of major salivary glands were investigated. These included 14 mucoepidermoid carcinomas, 13 adenoid cystic carcinomas, seven malignant mixed tumors, four adenocarcinomas, four salivary duct carcinomas, two acinic cell carcinomas, two undifferentiated carcinomas without lymphoid stroma, seven lymphoepithelioma-like carcinomas (LELCs), two squamous cell carcinomas, and one small cell carcinoma. EBV transcripts were examined by in situ hybridization using digoxigenin-labeled oligonucleotide antisense probe for EBV-encoded RNA 1 (EBER1) on formalin-fixed paraffin-embedded tissue sections. EBER1 was detected in the malignant epithelial cells in all seven cases of LELC, but not in any of the other carcinomas and the neighboring normal salivary gland tissue. Because all the EBV-negative cases showed satisfactory labeling with the poly d(T) probe, the negative reaction with EBER1 was unlikely to be caused by poor RNA preservation in the tissues. The seven cases of LELC, which were histologically indistinguishable from undifferentiated nasopharyngeal carcinoma (NPC), had a disease-free 4-year survival rate of 85.7%. The results suggest that LELC of the salivary gland in Taiwanese Chinese may share similar EBV-related pathogenesis with that of NPC.

Adult↗
PubMed1996

Clonal Epstein-Barr virus associated cholangiocarcinoma with lymphoepithelioma-like component.

Epstein-Barr virus (EBV) has been linked to several undifferentiated carcinomas of the aerodigestive tract, especially the nasopharynx, but has not been reported in the biliary tract. We here presented a case of an unusual cholangiocarcinoma harboring EBV genome in a 47-year-old Chinese woman. Physical examination in 1988 in Taiwan, including abdominal sonography of the liver, was essentially negative. She experienced three episodes of malaria in 1990 when she worked in Ghana, Africa, and felt a tumor mass in the epigastrium in October 1992. She received an extended left lobectomy for a huge hepatic tumor of 12 x 10 x 5.5 cm in February 1993. Light microscopy revealed a cholangiocarcinoma composed of both well-differentiated adenocarcinoma and lymphoepitheliomatous undifferentiated carcinoma components. Abundant EBV EBER1 was shown in both tumor components, but not in the nontumor liver. Southern blot analysis and polymerase chain reaction showed a monoclonal episomal form of EBV, with a genotype characteristic for Chinese EBV strain type 1. This finding suggests that the EBV infection preceded monoclonal EBV-harboring tumor cell expansion in this case.

Base Sequence↗
PubMed1996

Influence of patellar thickness on patellar tracking and patellofemoral contact characteristics after total knee arthroplasty.

Although total knee arthroplasty (TKA) has become a very common procedure, patellar problems remain a major cause of disability. Patellar thickness is one of the most challenging factors. The influence of patellar thickness on patellofemoral kinematics and contact characteristics following TKA was investigated. Seven unembalmed whole-lower-extremity cadaveric specimens were used. The kinematics was measured with a magnetic tracking device (3Space Tracker System, Polhemus Navigation Sciences Division, Colchester, VT). Contact area was calculated from the kinematic data and the digitized joint surface geometrics based on a theoretical method. The patellofemoral joint contact force was measured directly using a uniaxial force transducer. Kinematically, the influence of patellar thickness on patellar flexion, rotation, and proximodistal shift was not significant. Orthopaedic surgeons are often challenged by derangement of the patellofemoral joint, especially following TKA. It is commonly assumed that restoration of overall patellar thickness is most desirable. A thin patella can reduce the contact force, but it also poses the potential risks of stress fracture and anteroposterior instability. Increasing patellar thickness might be expected to increase the effective quadriceps moment arm at low flexion angles of the knee, but potentially reduces the range of motion of the knee and predisposes to patellar subluxation. Either a thicker or a thinner patella had a smaller contact area than intact and normal-thickness patella. Therefore, the surgical technique of patellar resurfacing during TKA should attempt to reproduce the original patellar thickness.

Aged↗
PubMed1996

Importance of soft tissue integrity on biomechanical studies of the patella after TKA.

This study evaluated the effects of soft tissue integrity on patellar tracking and patellofemoral joint force after total knee arthroplasty. The results indicate that partial dissection of the soft tissue integrity in the in vitro biomechanical studies of the patellofemoral joint can alter patellar tracking and joint force significantly, leading to improper conclusions.

Adipose Tissue↗
PubMed1996

Differential expression of EBER1 in nontumor nasopharyngeal biopsies and nontumor component of nasopharyngeal carcinoma.

The close association of Epstein-Barr virus (EBV) and nasopharyngeal carcinoma (NPC) is well documented and the expression of EBV-related latent genes has been shown in NPC. Nevertheless, the status of EBV infection in the nontumor epithelial and lymphoid cells is not known. In this study, we detected EBV in the nontumor component of NPC and nontumor nasopharyngeal biopsies by in situ hybridization using digoxigenin-labeled antisense EBER1 oligoprobe in 346 nasopharyngeal biopsies. Latent membrane protein (LMP) and ZEBRA were detected by immunohistochemistry in cases containing EBER1-positive cells. The EBV-positive epithelial and lymphoid cells were identified by immunostains for cytokeratin and lymphoid phenotypes. In the nontumor nasopharyngeal biopsies, 21 (11.7%) of 179 cases had EBV-harboring lymphocytes in the lymphoid tissue, while the overlying mucosa was all negative. LMP was demonstrated in lymphoid cells of 14 (66.7%) of these 21 samples. These EBV-positive lymphocytes were B lymphocytes by combined phenotype study. EBER1-containing metaplastic squamous cells were demonstrated in the overlying mucosa close to the tumor tissue in 14 (8.4%) of 167 NPC samples. In contrast, the respiratory epithelial cells in these cases were all negative. Two (1.2%) of these cases had EBV-positive lymphocytes in the lymphoid stroma. Four of the 346 cases had ZEBRA-positive cells. This study demonstrated that latent infection and, occasionally, active replication of EBV were present in stromal B lymphocytes in nasopharyngeal tissue with and without NPC. EBER1 was found only in the metaplastic squamous cells in the mucosa of nasopharyngeal tissues with NPC, but not in those without NPC.

Adolescent↗