Search PubMed⌕ Search

Biomedical subjects

J J Hwang

Publications and source records attributed to J J Hwang.

At least 127 records · Page 7Linked to original sources
PubMed1994

[4P- syndrome (Wolf-Hirschhorn syndrome) complicated with delay onset of malignant hyperthermia: a case report].

One 8-month-old female patient, weighted 5 kg, with congenital abnormality (4P- syndrome) underwent elective cheiloplasty for cleft lip and palate. Two hours later, with smooth anesthesia and operation, a life-threatening anesthetic complication of malignant hyperthermia occurred at pediatric intensive care unit. The immediate treatments were initially hyperventilating the patient with 100% O2 and cooling the patient with ice bags. Subsequently, intravenous dantrolene 2.5 mg/kg and symptomatic supportive care were administered successfully to treat the event. Upon reviewing the articles, we found that a congenital chromosome 4P deletion abnormality complicated with a delay onset of malignant hyperthermia has not been described previously.

Chromosome Aberrations↗
PubMed1994

[Treacher-Collin's syndrome and translaryngeal guided intubation--case report].

Treacher-Collin's (T-C) syndrome, a first-arch congenital defect, that often manifests with severe facial deformity. Though a rare condition, it offers challenges to an anesthesiologist especially during plastic surgical procedure. These challenges are: (1) difficulty in maintaining a patent airway and (2) difficulty in intubation during induction of general anesthesia. We would like to report a case using transtracheal passage of a retrograde guide wire into the oropharynx prior to laryngeal endotracheal intubation. The technique can, by no means, solve all airway problems. However, proper utilization of this technique may sometimes be life-saving.

Adult↗
PubMed1994

Nucleolar organizer regions in small cell carcinoma of lung.

Agyrophilic staining of nucleolar organizer regions (NOR) has been used to differentiate between cells of small cell carcinoma and lymphocytes in tissue specimens. We used cytologic smears which were previously Papanicolaou-destained to study the one-step agyrophilic staining technique for nucleolar organizer regions (AgNOR) in cell of small cell carcinoma and lymphocyte. The purposes of this study were to assess the feasibility and usefulness of AgNOR staining in diagnostic cytology and to try to set up a procedure that could be used on prestained smears for retrospective study. While the NOR of each lymphocyte appeared to be one round dot after AgNOR staining, the NOR of cell of small cell carcinoma showed dots, slightly variable in size and shape. The mean number of NOR was significantly higher (p < 0.01) in cells of small cell carcinoma (4.7 +/- 0.7) than in lymphocytes (1.4 +/- 0.4). In conclusion, AgNOR staining was demonstrated to be a useful method to differentiate between cells of small cell carcinoma and lymphocyte in Papanicolaou-destained smears.

Carcinoma, Small Cell↗
PubMed1994

Nucleolar organizer regions in smears of pleural effusion.

Agyrophil staining was applied to nucleolar organizer regions (NOR) to differentiate cells of adenocarcinoma and histiomesotheliosis in pleural effusion. The smears were either nuclearly unstained, but cytoplasmically counterstained by Papanicolaou method or Papanicolaou-destained before agyrophil staining of nucleolar organizer regions (AgNOR). The purposes of this study were to assess the feasibility and usefulness of AgNOR staining in diagnostic cytology and to try to set up a procedure that could be used on prestained smears for retrospective study. All smears showed good background and cellular outline. The distribution of NOR was either intranuclearly or in the nucleoplasm diffusely. In previously nuclearly unstained smears, NOR showed granular to powder-like appearance. The mean number of NOR in adenocarcinoma (38.4 +/- 12.5) was significantly higher than that in histiomesotheliosis (15.6 +/- 2.9). In Papanicolaou-destained smears, the NOR showed confluent dots. The mean number of NOR was much lower as compared to that of previously nuclearly unstained smears. Furthermore, the mean number of NOR in adenocarcinoma (3.6 +/- 1.4) showed no significant difference with that of histiomesotheliosis (2.7 +/- 0.8). In conclusion, AgNOR staining is one of the methods to differentiate benign from malignant cells, but not in Papanicolaou-destained smears.

Adenocarcinoma↗
PubMed1993

Usefulness of pulmonary venous flow pattern and maximal mosaic jet area detected by transesophageal echocardiography in assessing the severity of mitral regurgitation.

Pulmonary venous flow pattern detected by transesophageal echocardiography (TEE) has been reported to be a good marker of mitral regurgitation (MR) severity. In 89 patients with MR detected by TEE, both pulmonary venous flow pattern and maximal mosaic jet area were recorded for evaluating the severity of MR. Cardiac catheterization was performed in all patients for grading the severity of MR. Systolic reversed flow in pulmonary veins was a good marker for angiographic grade 3 or 4 MR with a sensitivity of 97% (33 of 34) and specificity of 95% (52 of 55). Maximal mosaic jet area had a good correlation with the grading of MR (r = 0.79). When a maximal mosaic jet area of > 6 cm2 was used to detect grade 3 or 4 MR, the sensitivity and specificity were lower than those of the systolic reversed flow (sensitivity 82 vs 97%, p = 0.073; specificity 80 vs 95%, p = 0.013). The accuracy of systolic reversed flow was not influenced by the cardiac rhythm or jet eccentricity. However, the sensitivity of maximal mosaic jet area was lower in patients with an eccentric jet than in patients with a central jet (67 vs 95%, p = 0.046). In conclusion, systolic reversed flow in pulmonary veins detected by TEE is better than the maximal mosaic jet area in detecting grade 3 or 4 MR, especially in patients with eccentric jet.

Adolescent↗
PubMed1993

Diagnostic accuracy of transesophageal echocardiography for detecting left atrial thrombi in patients with rheumatic heart disease having undergone mitral valve operations.

Transesophageal echocardiography (TEE) has emerged as an efficient method for detecting left atrial (LA) thrombi in recent years, but its accuracy has not been fully evaluated. A prospective clinicopathologic study in 213 consecutive patients with chronic rheumatic mitral valve disease over a period of 39 months was undertaken. All patients underwent open heart surgery within 3 days after the TEE study. The presence or absence of LA thrombi was confirmed at surgery by direct inspection of the left atrium and proven by histopathologic examination. Of the 213 patients, 147 had predominant mitral stenosis, and the remaining 66 patients had significant mitral regurgitation. Twenty-eight patients had LA thrombi by TEE criteria. These findings were all confirmed at surgicopathologic studies (specificity 100%). However, in 2 patients, LA thrombi were present but could not be detected by TEE (sensitivity 93.3%). Therefore, the positive predictive value was 100%, the negative predictive value was 98.9% and the diagnostic accuracy was 99.1%. No thrombi were found in patients with significant mitral regurgitation. The frequency of LA thrombi in patients with predominant mitral stenosis was 20% (30 of 147), and most of these patients had chronic atrial fibrillation (28 of 30, 93%). Only 16 patients (16 of 30, 53%) were found to have LA thrombi by transthoracic echocardiography. Furthermore, our data showed poor correlation between the echogenicity of LA thrombi and the degree of thrombus organization. Thus, TEE is excellent for detecting LA thrombi in patients with rheumatic heart disease severe enough to warrant mitral valve operations.

Adolescent↗
PubMed1993

Characterization of the transcription activation function and the DNA binding domain of transcriptional enhancer factor-1.

The regions of transcriptional enhancer factor-1 (TEF-1) required for its activation function and sequence-specific DNA binding have been determined. Deletion analysis of a chimera between TEF-1 and the GAL4 DNA binding domain (DBD) indicated that at least three regions of TEF-1 were involved in transactivation. However, none of these regions functioned as independent activating domains. Moreover, none of the GAL4 chimeras containing individual TEF-1 regions interfered with the activity of endogenous HeLa cell TEF-1, while interference was observed with the GAL4-TEF-1 chimeras which functioned as transactivators. These results indicate that there is a general correlation between the abilities of a given GAL4-TEF-1 chimera to function in transcriptional activation and interference, thus supporting the idea that transactivation by TEF-1 is mediated by a limiting transcriptional intermediary factor. In addition, we show experimentally that the TEA/ATTS domain is a novel class of DBD involved in the sequence-specific DNA binding of TEF-1 and its Drosophila homologue scalloped. Two other regions of TEF-1 are also required for DNA binding. These regions are not part of the minimum DBD, but may function by antagonizing the effect of sequences which negatively regulate DNA binding mediated by both the TEF-1 TEA/ATTS domain and the GAL4 DBD. In addition, analysis of TEF-1 and scalloped derivatives in which their TEA/ATTS domains have been interchanged further indicates that the TEA/ATTS domain is not the only determinant of DNA binding specificity.

Amino Acid Sequence↗
PubMed1993

Induction of sister chromatid exchange and micronuclei in primary cultures of rat and human hepatocytes by the peroxisome proliferator, Wy-14,643.

The ability of peroxisome proliferators to induce hepatocellular carcinomas in rodents has been known since the mid 1970's, but the mechanism of tumor formation is still poorly understood. In this study, we have used primary cultures of both rat and human hepatocytes to address the question of whether the peroxisome proliferator, [4-chloro-6-(2,3-xylidino)-2-pyrimidinylthio] acetic acid (Wy-14,643), causes genotoxic damage in hepatocytes as measured by sister chromatid exchange (SCE), micronuclei formation, and chromosomal aberrations. We have found that in rat hepatocytes the number of SCEs per chromosome increased in a dose-dependent manner from a background level of 0.7 to a maximum of 1.1 in cells exposed for 48 h to 100 microM of Wy-14,643. In contrast, no increase in SCE frequency was observed in rat hepatocytes exposed to Wy-14,643 for 3 h. A dose-dependent increase in micronuclei formation was also seen in the 48 h but not in the 3 h cultures. The maximum frequency of micronuclei formation after a 48 h exposure occurred at 20 microM Wy-14,643 and was 2.3 times that for control cells. At this concentration of Wy-14,643, the frequency of chromosomal aberrations was increased by more than 10-fold. A 48 h exposure to Wy-14,643 also significantly increased micronuclei formation in human hepatocytes, but it was less effective than in rat hepatocytes. To investigate the potential role of peroxisome proliferation in these genotoxic responses, we measured the activities of palmitoyl-CoA beta-oxidase in hepatocytes exposed for 48 h to Wy-14,643. A dose-dependent increase in palmitoyl-CoA beta-oxidase activity was observed in rat hepatocytes, but not in human hepatocytes. The SCE frequency in rat hepatocytes correlated well with the degree of peroxisome proliferation, however, the increased formation of micronuclei in both rat and human hepatocytes occurred by a mechanism that appeared to be independent of peroxisome induction. In summary, these results demonstrate that the peroxisome proliferator, Wy-14,643, causes genotoxic damage in primary cultures of both rat and human hepatocytes.

Analysis of Variance↗
PubMed1993

Infective endocarditis in the transesophageal echocardiographic era.

During a 45-month period, 50 consecutive patients with infective endocarditis were evaluated at the National Taiwan University Hospital with emphasis on the role of transesophageal echocardiography (TEE) in the management of these patients. Among them, rheumatic heart disease was still the most common underlying cardiac disorder (10/50, 20%), while mitral valve prolapse (8/50, 16%) and congenital heart disease (8/50, 16%) were also frequently encountered. More than one third (19/50, 38%) had no underlying heart disease. Four intravenous drug abusers, quite rare previously in Taiwan, were found during the study period. Native valves involved were mostly mitral valve (n = 18), aortic valve (n = 15), and both mitral and aortic valves (n = 3). Tricuspid valve and pulmonic valve were involved in 3 and 2 patients, respectively. Streptococcus viridans was the leading microorganism isolated (21/50, 42%). Staphylococci and enterococci were found in 9 (18%) and 5 (10%) patients, respectively. Twelve patients (24%) were culture-negative in this series. Embolic complications occurred in 13 patients (26%), with a total of 17 episodes. No significant correlation was found between the occurrence of embolization and the vegetation size or the location of the vegetation, if patients with right-sided valvular vegetation and no identifiable vegetation were excluded. Surgery was needed by 25 patients (50%), and mortality occurred in 6 (12%). TEE was superior to transthoracic echocardiography in the detection of vegetations at the mitral or prosthetic valves. Concerning the associated complications with infective endocarditis, TEE was also superior in estimating the severity of mitral regurgitation, recognizing ruptured chordae tendineae and detecting subaortic complications such as valve ring abscess and mitral valve perforation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Traumatic rupture of the pericardium with a peculiar chest radiographic finding.

A 46-year-old man was admitted because of progressive exertional dyspnea and pulsating neck vein for 3 years. He had a history of car accident with his chest struck by the steering wheel 10 years previously. Physical checkup and laboratory studies revealed severe tricuspid regurgitation. The chest radiography disclosed mild cardiomegaly and shift of the heart towards the left hemithorax with a bizarre cardiac silhouette showing double contour over the left ventricular border, suggesting the possibility of partial absence of the left pericardium. The latter diagnosis was confirmed at open heart surgery for the associated severe tricuspid regurgitation.

Accidents, Traffic↗
PubMed1993

Usefulness of transesophageal echocardiography in the treatment of critically ill patients.

To evaluate the usefulness of transesophageal echocardiography (TEE) in the treatment of critically ill patients, 80 patients (51 male and 29 female; mean age, 53 years) undergoing both transthoracic echocardiography (TTE) and TEE were studied in a 2-year period. Of these, 48 patients were studied in the ICU, while the other 32 patients were directly referred from the emergency departments. Indications for the study included suspected aortic dissection (34 patients), hemodynamic instability (22 patients), suspected cardiac source of embolism (11 patients), evaluation of the severity of mitral regurgitation (7 patients), and suspected infective endocarditis (6 patients). The probe was passed successfully in 78 of 80 attempts (98 percent). No significant complications were recorded during the transesophageal echocardiographic study. Transesophageal echocardiography provided critical information that was not obtained by TTE in 39 of 78 studies (50 percent, p < 0.005). Cardiac surgery was prompted by TEE findings in 14 patients (18 percent) and these findings were all confirmed at operation. Transesophageal echocardiography was a safe, well-tolerated, and valuable diagnostic approach for the rapid detection of specific cardiac abnormalities in patients with critical illness; TEE should be considered in the treatment of critically ill patients especially when TTE provided inadequate information.

Adolescent↗
PubMed1993

Resolution of left atrial thrombi after anticoagulant therapy in patients with rheumatic mitral stenosis: report of four cases.

The presence of a left atrial thrombus is considered to be a relative contraindication to percutaneous transvenous mitral commissurotomy (PTMC) in patients with rheumatic mitral stenosis. However, resolution of left atrial thrombus after anticoagulant therapy with warfarin makes PTMC possible. From July 1989 to June 1991, a total of 70 patients with rheumatic mitral stenosis received PTMC at National Taiwan University Hospital. Of these, four patients underwent PTMC uneventfully after resolution of left atrial thrombi with anticoagulant therapy. The prothrombin time was kept at around 1.5 times that for the normal controls and transesophageal echocardiography (TEE) was used for follow-up. The time for resolution of left atrial thrombi was 1.5, 11, 12, and 2 months. In all four patients with chronic atrial fibrillation, TEE revealed the presence of left atrial thrombi; in only two of these cases was there a suspicion of left atrial thrombi on transthoracic echocardiography. It is concluded that: (1) left atrial thrombi may be resolved after anticoagulant therapy with warfarin, but the time required varies for different patients; and (2) TEE is better than conventional transthoracic echocardiography for detecting a left atrial thrombus and is recommended as the tool of choice for observing the response of a left atrial thrombus to anticoagulant therapy.

Adult↗
PubMed1993

Valve ring abscess associated with infective endocarditis: echocardiographic features and clinical observations.

The presence of a valve ring abscess in patients with infective endocarditis adds appreciably to the expected rates of morbidity and mortality. From January 1989 to October 1991, a total of 43 consecutive patients with infective endocarditis seen at National Taiwan University Hospital were enrolled in this study. There were 30 men and 13 women, ranging in age from 14 to 75 years (mean +/- SD 38.5 +/- 15.0 years). The presence of infective endocarditis was documented by surgery in 26 patients and was based on a clinical diagnosis in the remaining 17 patients. A valve ring abscess was detected in five patients, either by transthoracic or transesophageal echocardiography, and all were confirmed at surgery. Aortic valve endocarditis was more frequently found in patients with valve ring abscesses (100% vs 31.6%, p < 0.01), and the infecting organism was most often Staphylococcus aureus (60.0% vs 15.8%, p < 0.05). The proportion of urgent operations was also higher in the group with abscesses (80.0% vs 23.7%, p < 0.05). The hospital mortality was 40.0% in patients with abscesses and 5.3% in patients without abscesses, but the difference did not reach significance (p = 0.056). Transthoracic echocardiography identified valve ring abscesses in the first three patients, but transesophageal echocardiography was more useful in detecting abscesses located in the posterior aspect of the aortic root in the other two patients, in which the lesion was overlooked or only suspected by the transthoracic approach.(ABSTRACT TRUNCATED AT 250 WORDS)

Abscess↗
PubMed1993

Cardiac amyloidosis presenting as sick sinus syndrome and intractable heart failure: report of a case.

Cardiac amyloidosis, an uncommon disease, has been reported to manifest as congestive heart failure (CHF) and/or various arrhythmias. Herein, we report a case of CHF and sick sinus syndrome. The patient, a 66-year-old man, was admitted to the National Taiwan University Hospital because of dizzy spells and recurrent syncope. Electrocardiogram showed a sinoatrial block, first degree atrioventricular block, right bundle branch block and low-voltage Q wave, R wave and S wave (QRS) complex. Prolonged corrected sinus node recovery time was documented by an atrial pacing study. A permanent pacemaker was implanted for the patient's bradyarrhythmia, but he developed progressive heart failure. Echocardiography revealed a normal-sized ventricular chamber, concentric left ventricular hypertrophy with a "granular sparkling" appearance of the myocardium, and impaired diastolic and systolic function of the left ventricle. Despite aggressive treatment, the patient expired due to intractable heart failure. Postmortem needle aspiration revealed amyloidosis involving the heart, lung and skin. We conclude that cardiac amyloidosis should be considered in elderly patients with conduction disturbance and unexplained congestive heart failure.

Aged↗
PubMed1993

Clinical study of Mycoplasma pneumoniae pneumonia.

From 1982 to 1991, we experienced 76 patients with Mycoplasma pneumoniae pneumonia which were confirmed by serologic tests. There were 32 (42%) male and 44 (58%) female patients. One patient had underlying disease of diabetes mellitus while the other patients were in good health. The age ranged from 9 months old to 72 years old. All the patients complained of fever and coughing; 63% had dry cough and 37% had sputum production. Upper respiratory tract complaints such as rhinorrhea, sore throat, or earache were noted in 57% of the patients. Fifty-five percent of the patients had GI symptoms of anorexia, nausea, vomiting, or diarrhea. Other complaints included myalgia/arthralgia (29%), headache (30%), and general malaise (32%). Dyspnea (17%) and chest pain (20%) were occasional complaints. Seventy-one percent of the patients had WBC counts < 10000/cu mm and 29% > 10000/cu mm. The mean value of C-reactive protein (CRP) was 53.1 micrograms/ml, while 16% of the patients had a CRP value above 100 micrograms/ml. Thirty-one percent of the patients were noted to have a transient elevation of serum transaminase. Four different patterns of infiltration were seen in chest radiographic manifestation: 1) peribronchial and perivascular interstitial infiltrates (18.4%), 2) nonhomogeneous patchy consolidations (22.4%), 3) homogeneous acinar consolidations (27.6%), and 4) mixed interstitial and alveolar infiltrates (27.6%). Interstitial infiltration was more commonly seen in pediatric than adult patients (46% vs 20%). Other features of the radiologic manifestation were as follows: unilateral lesions in 80% of patients, single lobe lesions in 77%, lower lobe predominant in 69%, pleural effusion in 7%, and radiographic deterioration in 10%. Mycoplasmal pneumonia should be considered in the differential diagnosis of community-acquired pneumonias.

Adolescent↗