Biomedical subjects

J H Chiang

Publications and source records attributed to J H Chiang.

At least 37 records · Page 2Linked to original sources

PubMed1999

Case report: portal vein thrombosis associated with hereditary protein C deficiency: a report of two cases.

Protein C deficiency is one of the causes of curable or preventable portal vein thrombosis. We report two patients of portal vein thrombosis associated with hereditary protein C deficiency. The first patient presented with continuous right upper quadrant pain and high fever. The abdominal sonography revealed normal liver parenchyma but portal vein and superior mesenteric vein thrombosis. Based on a 55% (normal 70-140%) plasma protein C level, he was diagnosed as having protein C deficiency. A trace of his family history showed that his elder brother also had protein C deficiency with a 50% plasma C level. Both patients received anticoagulant therapy. The younger brother showed good response. Unfortunately, the elder one suffered from recurrent episodes of variceal bleeding and received a life-saving splenectomy and devascularization. We herein remind clinicians that early screening and therapy are helpful in preventing late complications of protein C deficiency with portal vein thrombosis.

Abdomen, Acute↗

PubMed1999

Supportive treatment, resection and transcatheter arterial chemoembolization in resectable hepatocellular carcinoma: an analysis of survival in 419 patients.

OBJECTIVE AND DESIGN: Both surgical resection and transcatheter arterial chemoembolization (TACE) are effective treatments for hepatocellular carcinoma (HCC). Few reports have compared the different treatment modalities for resectable HCC based on clinically matched groups. The aim of this study was to compare the survival rate after surgery, TACE or supportive treatment in resectable HCC patients, and also in elderly patients (> or = 70 y/o). METHODS: From 1984 to 1993, 419 consecutive patients with resectable HCC were included in this study. Of these, 311 (74%) underwent resection of tumours and 46 (11%) refused operation, opting instead for TACE. The remaining 62 (15%) who refused both methods of treatment were given supportive care. Univariate and multivariate analyses for prognostic factors and the 5-year survival rate among the groups were studied. RESULTS: Both surgical resection and TACE groups had a better 5-year survival rate than the supportive treatment group (43% and 34% vs. 7%). There was no difference in survival between the surgery and TACE groups. However, the 5-year survival rate was 11% in TACE and 41% in the surgical group when the patients were > or = 70. In multivariate analysis, female sex (P = 0.0466), tumour size < or = 3 cm (P = 0.0001), alpha-fetoprotein (AFP) < 400 U/l (P = 0.0036), single tumour (P = 0.0474), serum creatinine < or = 1.5 mg/dl (P = 0.0006) and alkaline phosphatase (AP) < or = 100 U/l (P = 0.0007) are associated with good prognosis for resectable HCC. CONCLUSION: TACE is an alternative for resectable HCC. Tumour size, tumour number, AFP level, renal function, AP level and female sex are prognostic factors. In elderly people, TACE must be used prudently and has a worse prognosis.

Age Factors↗

PubMed1999

Functional expression of hMYH, a human homolog of the Escherichia coli MutY protein.

We have previously described the hMYH cDNA and genomic clones (M. M. Slupska et al., J. Bacteriol. 178:3885-3892, 1996). Here, we report that the enzyme expressed from an hMYH cDNA clone in Escherichia coli complements the mutator phenotype in a mutY mutant and can remove A from an A. 8-hydroxydeoxyguanine mismatch and to a lesser extent can remove A from an A. G mismatch in vitro.

8-Hydroxy-2'-Deoxyguanosine↗

PubMed1999

Arachnoid granulations--computerized tomography and magnetic resonance imaging features: a case report.

A 71-year-old woman had arachnoid granulations found in the straight and transverse sinuses on computerized tomography (CT) and magnetic resonance imaging (MRI). The arachnoid granulations appeared as low-density masses on CT. They gave low signals on T1-weighted MR images and high signals on T2-weighted images. Arachnoid granulations are usually of no clinical significance. They have characteristic CT and MRI manifestations and should not be mistaken for sinus thrombosis or intrasinus tumors.

Aged↗

PubMed1999

Intracranial pathology: comparison of intraoperative ultrasonography with computerized tomography and magnetic resonance imaging.

BACKGROUND: High-resolution, real time, intraoperative ultrasonography (IOUS) has been used in a number of cases in our neurosurgical department to identify, localize and characterize intracranial abnormalities. We compare the images of IOUS with those of computerized tomography (CT) and magnetic resonance imaging (MRI) in order to enhance our experience and confidence. METHODS: IOUS images were compared with preoperative CT scans and/or MRIs in 30 intracranial masses. Tumor size and margin, echogenicity and edema were the features compared. RESULTS: The images of IOUS, CT and MRI correlated closely except for images of primary gliomas. IOUS was more effective than CT and MRI in delineating the extent of a glioma, determining whether a lesion was cystic, with or without septation, or solid and in guiding surgical procedures. The contrast enhancement available with CT and MRI could not be demonstrated with IOUS. CONCLUSIONS: IOUS provides exquisite detail of intracranial pathology as well as, or even better than, CT and MRI. Its application should be emphasized to minimize damage of normal brain tissue and increase the completeness of tumor resection.

Adult↗

PubMed1999

Magnetic resonance imaging of unilateral olivary hypertrophy due to pontine tegmental hemorrhage: a case report.

Olivary hypertrophy (OH) is not a primary lesion but, rather, develops as a lesion of the Guillain-Morraret triangle, which is composed of the contralateral dentate nucleus, the ipsilateral red nucleus and the ipsilateral inferior olivary nucleus. OH is usually accompanied by palatal myoclonus or other involuntary movements such as extremity myorhythmia. One case of unilateral OH following ipsilateral pontine tegmental hemorrhage is presented. Magnetic resonance imaging (MRI) showed high signal intensity in the inferior olivary nuclei on T2- and proton-density-weighted images. Enlargement of the inferior olivary nuclei was also noted. MRI may currently be the only procedure capable of confirming the diagnosis.

Cerebral Hemorrhage↗

PubMed1999

Giant cell reparative granuloma: a case report.

Giant cell reparative granuloma (GCRG) is an infrequent benign lesion with undetermined etiopathogenesis affecting the maxillary and mandibular bone and, rarely, the skull. It is also extremely rare in the sphenoid bone. GCRG is usually diagnosed by histologic examination of bone lesions. We report a case of GCRG originating from the sphenoid bone. Computerized tomography revealed an expansile lesion with thinning or destruction of the cortical bone. The lesion itself was slightly hyperdense with good but inhomogeneous contrast enhancement. Reported magnetic resonance image findings showed hyperintensity on both T1-weighted and T2-weighted images and variable contrast enhancement. Plain skull radiographs usually reveal a lytic lesion within the bone.

Child↗

PubMed1999

Hepatocellular carcinoma with mediastinal and pericardial invasion: report of two cases.

Mediastinal invasion with pericardial involvement in hepatocellular carcinoma (HCC) is rarely described. We report two patients with hepatitis-C-related HCC, who, after several courses of transcatheter arterial chemoembolization (TACE), developed mediastinal and pericardial neoplastic growth. Both patients presented with clinical manifestations of exertional dyspnea, chest pain and orthopnea. The diagnosis of HCC with pericardial involvement, through direct invasion of the anterior mediastinum, was established by computerized tomography and magnetic resonance imaging. These patients' symptoms were relieved after they received radiotherapy with a total dosage of 3,000 and 4,000 cGy over a three-week and four-week period, respectively. We suggest that direct mediastinal invasion with pericardial involvement should be considered when evaluating patients with advanced HCC who developed precordial distress following palliative TACE. Early recognition of this unusual complication is important in the management of HCC.

Aged↗

PubMed1999

Genital tuberculosis with peritonitis mimicking Meigs' syndrome: a case report.

A 19-year-old girl presented with genital tuberculosis (TB) complicated with peritonitis and pleural effusion. In addition to oligomenorrhea, her initial presentation included symptoms of intermittent high fever, exertional dyspnea, productive cough and body weight loss. Acid-fast bacilli were identified by sputum culture. She continued to suffer from persistent abdominal discomfort and body weight loss after eight months of anti-TB treatment. Finally, exploratory laparotomy was performed under the suspicion of Meigs' syndrome or TB peritonitis. Operative findings included diffusely granulomatous change over the peritoneum, ovaries, endometrium, intestine and liver. Histologic examination of the ovaries and endometrium showed caseous necrosis associated with Langhan's giant cells and epithelial cells. Acid-fast stain revealed numerous acid-fast bacilli. She was discharged after two months of anti-TB treatment. Anti-TB therapy was continued for one year after discharge. During 3 years of post-discharge follow up, she was free of abdominal discomfort and had given birth to two healthy children.

Adult↗

PubMed1998

Pictorial review: Radiological diagnosis of duodenal abnormalities.

This article depicts the radiological findings of many common gastrointestinal entities. Specifically, examples of disease processes that affect the stomach, gall bladder, small intestine, pancreas and colon are shown. In most cases there is correlation between ultrasound, computed tomography (CT) and fluoroscopic imaging. The major emphasis of the article, however, is to demonstrate classic barium imaging of a large number of gastrointestinal disease processes.

Barium Sulfate↗

PubMed1998

Ultrasound-guided interventional procedures in splenic abscesses.

The results of ultrasound (US)-guided interventional procedures over a period of 12 years in 21 consecutive patients with splenic abscess were reviewed. The interventional procedures were done with 21- or 18-gauge needles for aspiration of relatively small abscesses (< 3.5 cm) in eight patients and with an 8.3-9.0 French pigtail catheter for continuous drainage in 13 patients with larger abscesses (> or = 3.5 cm). In some patients, multiple abscesses were treated separately according to their various sizes. More than one catheterization were done in three patients because of detached catheter or recurrent abscesses. The interventional procedures were followed by at least eight weeks of appropriate antibiotic therapy. Only one patient had the complication of minimal subcapsular hematoma which needed no further treatment. All the patients had uneventful clinical courses. US-guided interventional procedure proved to be a treatment-of-choice for splenic abscess, and may avoid splenectomy by conserving the spleen.

Abscess↗

PubMed1998

A hybrid neural network model in handwritten word recognition.

A hybrid neural network model is developed and applied to handwritten word recognition. The word recognition system requires a module that assigns character class confidence values to segments of images of handwritten words. The module must accurately represent ambiguities between character classes and assign low confidence values to a wide variety of non-character segments resulting from erroneous segmentations. The proposed hybrid neural model is a cascaded system. The first stage is a self-organizing feature map algorithm (SOFM). The second stage maps distances into allograph membership values using a gradient descent learning algorithm. The third stage is a multi-layer feedforward network (MLFN). The new system performs better than the baseline system. Experiments were performed on a standard test set from the SUNY/USPS Database.

Journal Article↗

PubMed1998

Examination of the role of DNA polymerase proofreading in the mutator effect of miscoding tRNAs.

We previously described Escherichia coli mutator tRNAs that insert glycine in place of aspartic acid and postulated that the elevated mutation rate results from generating a mutator polymerase. We suggested that the proofreading subunit of polymerase III, epsilon, is a likely target for the aspartic acid-to-glycine change that leads to a lowered fidelity of replication, since the altered epsilon subunits resulting from this substitution (approximately 1% of the time) are sufficient to create a mutator effect, based on several observations of mutD alleles. In the present work, we extended the study of specific mutD alleles and constructed 16 altered mutD genes by replacing each aspartic acid codon, in series, with a glycine codon in the dnaQ gene that encodes epsilon. We show that three of these genes confer a strong mutator effect. We have also looked for new mutator tRNAs and have found one: a glycine tRNA that inserts glycine at histidine codons. We then replaced each of the seven histidine codons in the mutD gene with glycine codons and found that in two cases, a strong mutator phenotype results. These findings are consistent with the epsilon subunit playing a major role in the mutator effect of misreading tRNAs.

Amino Acid Sequence↗

PubMed1998

Normal and variant anatomy of hepatic arteries: angiographic experience.

BACKGROUND: Anatomic variation of hepatic arteries is reported to occur in 25-50% of the general population. Knowledge of the existing variations is important in planning and conducting surgical or radiologic procedures in the upper abdomen, such as liver transplantation and transarterial chemo-embolization (TACE). METHODS: Based on data from 321 patients undergoing upper abdominal arteriography, hepatic artery anatomy was analyzed and classified into three groups (single, double and multiple hepatic arteries at hepatic hilum) according to Suzuki's classification. Each group was subdivided into three types (celiac, mesenteric and mixed types) according to the origin of the hepatic arteries. The variations within each type were recorded. RESULTS: Two hundred and sixty one patients (68.%) had single hepatic arteries. One hundred and five patients (27.6%) had double hepatic arteries and only fifteen patients had multiple hepatic arteries. All of these variants, including twenty subtypes, were identified. CONCLUSIONS: This study, based on Suzuki's classification, provides basic data for the anatomic variations of hepatic arteries for the Chinese population in Taiwan.

Female↗

PubMed1998

Severe colonic complications in acute pancreatitis.

BACKGROUND: Colonic complications in patients with acute pancreatitis may be very severe and have rarely been analyzed in Chinese patients. METHODS: We retrospectively evaluated 1,637 patients with acute pancreatitis who were admitted to the Veterans General Hospital-Taipei from January 1986 to December 1995 in order to identify those with severe colonic complications. The clinical, radiologic and pathologic features and surgical findings in these patients are reviewed. RESULTS: Eight of 1,637 patients with acute pancreatitis had severe colonic complications. Six of them were diagnosed between two and eight weeks after the onset of clinical pancreatitis. All had a Ranson's score of at least 3. Four patients, including one with hematochezia, had a strong positive reaction for occult blood in stool specimens. Computed tomography (CT) revealed necrotizing pancreatitis and colonic wall swelling in all eight patients. Colonic involvement was discovered by CT in two patients prior to surgery, one with colocutancous fistula and the other with colonic perforation. The other six patients were found to have colonic involvement incidentally at the time of laparotomy. All of the colonic involvements were located near the splenic flexure. In addition to necrosectomy, three patients underwent segmental hemicolectomy and the remaining five patients had simple closure of the perforation. Diverting loop ileostomy or colostomy was also carried out in all patients. Three patients (34%) died of overwhelming sepsis superimposed on the subsequent multiple organ failure between 44 and 122 days after the onset of pancreatitis. CONCLUSIONS: Severe colonic complications of acute pancreatitis are rare. Although preoperative diagnosis is difficult, CT may be helpful to make an early diagnosis. These complications should be suspected in patients with severe acute pancreatitis when acute lower gastrointestinal hemorrhage or positive stool occult blood is found two to eight weeks after the onset of pancreatitis or when CT reveals necrotizing pancreatitis and colonic wall swelling; this will allow early surgical intervention.

Acute Disease↗

PubMed1998

High resolution computed tomography of temporal bone fracture.

BACKGROUND: High resolution computed tomography (HRCT) is highly efficient in demonstrating the anatomy of the temporal bone. This study evaluates its application to temporal bone fractures (TBF). METHODS: We collected data from 26 cases of TBF in the past two years. All cases underwent HRCT examination. The clinical information was reviewed and correlated with the imaging findings. RESULTS: Eighty-six percent of the cases had longitudinal fractures. Axial scans were the most useful in identifying the fracture line. Mastoid opacification on routine head computed tomography (CT) was also useful in indicating possible TBFs. Complications of TBF, such as ossicular chain disruption, facial nerve damage or otorhino-liquorrhea, were identified clearly using HRCT. CONCLUSIONS: To minimize or prevent the sequelae of TBF, accurate radiologic evaluation is necessary as soon as possible after injury. HRCT of the temporal bone delineates the bony and soft tissue anatomy with high accuracy and we recommend it as the diagnostic modality of choice.

Adolescent↗

PubMed1998

Recurrent spontaneous bacterial empyema in cirrhosis: a case report.

Spontaneous bacterial empyema occurs in about 0.4% of cirrhotic patients, but recurrent attack has rarely been reported. Herein we report a case of repeat episodes of spontaneous bacterial empyema. The patient presented with fever, shortness of breath and three episodes of spontaneous bacterial empyema (accompanied by septic shock in two episodes) within six months. Chest roentgenography showed massive right-side pleural effusion. Thoracentesis yielded pleural effusion containing a neutrophil count of more than 500/microliter. A blood culture grew non-O1 Vibrio cholerae in one episode and the pleural effusion culture grew Aeromonas hydrophila. A chest-tube was inserted during the latest episode due to a low pH and glucose concentration in the pleural fluid. The patient recovered well after medical treatment. The etiology, diagnosis and management of spontaneous bacterial empyema are discussed.

4-Quinolones↗

PubMed1997

Selective intra-arterial calcium injection in the investigation of adult nesidioblastosis: a case report.

A 69-year-old man with recurrent hypoglycaemia had inappropriately elevated plasma insulin level during a symptomatic hypoglycaemia, but had a negative prolonged fast. Computerized tomography (CT) of the abdomen revealed a nodular lesion over the body of pancreas, whereas pancreatic arteriography failed to show tumour blush. Hence, arterial stimulation (with calcium) and venous sampling (ASVS) was performed and a brisk response of plasma insulin level was found when calcium was injected both into the splenic and the superior mesenteric arteries. Since no tumour was found during the operation, the patient received subtotal distal pancreatectomy. Pathological examination of the resected tissue disclosed a typical finding of nesidioblastosis. We suggest that selective intra-arterial calcium injection with hepatic venous sampling for insulin gradients is useful for the diagnosis of adult nesidioblastosis.

Aged↗