Volume 114  ·   Issue 01  ·  2001

Objective To study the clinical characteristics of 2952 patients with epilepsy who had received drug treatment from the neurology outpatient clinics of eight major hospitals in Hong Kong. Methods Retrospective review of outpatient records. Results 1601 (54.3%) males and 1351 (45.7%) females with a median age of 35.8 years (range, 10-94.8) were studied. Seizure types included generalized tonic-clonic in 80.7%of patients, complex partial in 28.3%, simple partial in 14.4%, atypical absence in 2.6%and myoclonic in 1.4%, and 30.4%of patients had more than one seizure type. EEG, CT brain, MRI brain and neuropsychological evaluation were obtained in 81 .2%, 61 .7%, 17.0% and 2.2%of patients, respectively. The etiology of epilepsy was cryptogenic in 59.9%, symptomatic in 35.1 %and idiopathic in 3.9%; the commonest were intracranial infection, cerebral vascular disease, cranial trauma and perinatal insult. Phenytoin,carbamazepine and valproate were the most frequently used drugs and 25.9%of patients were taking more than two drugs. 48.3%of patients had active seizures in the past six months and 26.4%were considered to have unsatisfactory control of their epilepsy. Medical refractoriness of epilepsy was associated with a history of perinatal insult, intracranial infection, congenital brain malformation, intracranial neoplasm,cerebral vascular disease, hippocampal sclerosis, mental retardation and a history of status epilepticus(P<0.05). Conclusion In this local cohort of adult patients with epilepsy under specialist care, there were a considerable number of patients falling into the category of cryptogenic epilepsy. Risk factors associated with medical refractoriness are similar to previous studies. Chin Med J 2000; 114(1): 84-87

Objective To observe the level of muscarinic receptors in airway and lung tissues, and the effect of inhaled ipratropium bromide on these receptors in a rat model of chronic obstructive pulmonary disease(COPD). Methods This model was developed by exposure of rats to 250 ppm SO2 gas, 5 h/d, 5 d/wk, for a period of 7 wk. The COPD rats inhaled 0.025%aerosolized iratropium bromide for 20 min, 2 times daily, in an airtight chamber. Muscarinic receptors in airway and lung tissues of normal rats, ipratropium bromide-treated COPD rats and the recovering COPD rats were measured by the radioligand binding assay. Results Airway/lung pathology and pulmonary function tests showed that chronic SO2 exposure caused pathophysiologic changes similar to those observed in human COPD. The density(0.038 ± 0.011, pmol/mg protein)and affinity(Kd, 23±11 pmol/L)of muscarinic receptors in airway and lung tissues of COPD rats were not changed compared with those of normal control rats(0.030 ±0.008 and 29 ± 19, respectively, P>0.05). Densities of the muscarinic receptors were not changed after inhalation of ipratropium bromide for 5 days, but increased significantly after inhalation for 30 days, as compared with those of the untreated COPD rats. The muscarinic receptors returned the normal levels at day 6 after cessation of ipratropium bromide treatment. There were no differences among different groups of rats in equilibrium dissociation constants(Kd). Conclusion A rat model of COPD with pathophysiologic changes similar to the human counterpart was developed using chronic SO2 exposure. There was no significant change in the number and function of muscarinic receptors in airway and lung tissues of the COPD rats, but upregulation of the muscarinic receptors was observed after long-term inhalation of ipratropium bromide. Chin Med J 2001; 114 (1): 80-83

Objective To determine the origin of human influenza A (H9N2) virus and the relationship among H9N2strains isolated from different hosts, on the basis of molecular biology. Methods Viruses were passed in embryonated hen eggs, and virion RNA was extracted from allantoic fluid and reverse transcribed to synthesize cDNA. cDNA was amplified by PCR and the PCR product was purified with a purification kit. Afterwards RNA sequence analysis was performed by dideoxynucleotide chain termination and a cloning method. Finally, phylogenetic analysis of the sequencing data was performed with MegAlign (version 1.03) and Editseg (version 3.69) softwares. Results The amino acid sequences at the cleavage site between HA1 and HA2 domains of H9N2 viruses isolated in China are R-S-S-R. One pigeon strain contains seven potential glycosylation sites on the HA protein molecule, while all others have eight. There are 2 to 15 differences of amino acid sequences distributed at 24 different positions on the HA protein molecules among six H9N2 viruses. The H9N2 viruses with multiple lineages of HA genes were co-circulating in China recently. Conclusion The highest possibility is that human influenza A (H9N2) virus was derived from Chicken H9N2 virus, and not derived from pigeon H9N2 virus. However, it is still unknown whether the H9N2 virus could transmit from person to person. The H9N2 viruses with multiple lineages of HA genes are co-circulating in China. Chin Med J 2001; 114(1): 76-79

Objective To evaluate the clinical value of sequential subtraction scintigraphy (SSS) with 99mTc red blood cell (RBC) for the early detection of gastrointestinal (GI) bleeding. Methods Ninety patients referred with clinical evidence of GI bleeding underwent 99mTc-RBC scintigraphy with digital gamma camera after labeling of 99mTc-RBC in vivo. Sequential 12 conventional non-subtraction(CNS) images of abdomen were taken at 5 min intervals for 60 min. Then 5-min images were subsequently subtracted from each other using a computer and 11 subtracted images were obtained. Delayed images up to 24 hr were obtained when early results were negative and/or recurrent bleeding was suspected. Results 62 of 90 patients with suspected GI bleeding were conformed to have active hemorrhage up to 24hr. The scintigrams were divided into the following three sets: within 30 min, 60 min, and 24 hr. The sensitivity of SSS was 87%(54/62, 30 min) and 91.9%(57/62, 60 min) respectively, which were significantly higher (P<0.05) than that of CNS (56.4%, 35/62 and 62.9%, 39/62). 24 hr delayed image of CNS increased the sensitivity to 85.4%. No significant difference in specificity between the two methods was noted. Of the 62 patients with definite active hemorrhage, the bleeding sites were identified by surgical operation in 42. The concordant rate with surgical operation in SSS was 92.8%(39/42), higher than that of CNS (73.8%. 31/42). Conclusions Sequential subtraction scintigraphy with 99mTc-RBC, compared with conventional non-subtraction scintigraphy, is an effective technique for the early detection of GI bleeding. It increases the diagnostic sensitivity, detecting a small amount of bleeding earlier than CNS; SSS reduces background activity, more accurately localizing bleeding sites. It also shortens the examination time, making this approach more suitable for pediatric, elderly and critically ill patients. Chin Med J 2001; 114 (1): 69-72

Objective To identify aldosterone synthase gene-CYP11B2 mRNA expression in normal and fibrotic liver in rats and evaluate the curative effect of antisterone. Methods 160 Wistar rats weighing about 250 g were divided into 4 groups. In the model group (n=40),the rats were injected with 40%CCI4 (0.25 ml/100 g) subcutaneously three times a week. In the antisterone group (n=40), the rats were injected with 40%CCI4 (0.25 ml/100 g) subcutaneously three times a week. Antisterone equivalent to 20 mg•kg-1 • d-1 was given intragastrically (ig) . In the malotilate group (n=40), the rats were injected with 40%CCI4(0.25 ml/100 g) subcutaneously three times a week. Malotilate equivalent to 50 mg•kg-1 • d-1 was given ig. In the control group (n=40), the rats were injected with olive oil only. After 2, 4, 6, 8 and 10 weeks, animals were sacrificed, and morphological examination was carried out. The area of collagen was examined with an Image Analyse System. Expression of the aldosterone synthase gene, CYP11B2 mRNA, in fibrotic and normal liver was detected by means of reverse transcriptase polymerase chain reaction (RT-PCR) and in situ hybridization. Results In situ hybridization and RT-PCR showed that the expression of CYP11B2 mRNA, which localized in the endoplasm of hepatic stellate cells (HSCs), was up regulated when fibrogenesis occurred. Histological observation indicated that the grade of fibrosis and the area of collagen in the antisterone group were less than those in model group before 6 weeks (P <0.05). There was no significant difference between the antisterone and malotilate groups (P> 0.05) . After that, however, the grade of fibrosis and the area of collagen in the antisterone group were higher than those in the malotilate group (P <0.05). There was no significant difference between the antisterone and model groups (P> 0.05). Conclusions The expression of CYP11B2 mRNA is up regulated in fibrotic liver. Antisterone can have a partial fibrogenesis-inhibiting effect in the early stages. Chin Med J 2001; 114(1): 64-68

Objective To examine the effect of endovascular irradiation on restenosis after balloon angioplasty in rabbit. Methods After the establishment of rabbit iliac atherosclerosis model, balloon angioplasty was performed at the lesion segment of the iliac artery. Rabbits were randomly divided into three groups: control group, 10Gy irradiated group and 18 Gy irradiated group. Endovascular irradiation was performed for irradiated groups at the dilated sites by introducing the 192lr radioactive guidewire through a catheter. After four weeks, the animals were killed and the target segments were cut down. Histopathologic and morphometric analyses were carried out. Results The mean final lumen area in the 18 Gy group was larger than that in the control or 10 Gy group(P<0.05) . The intimal area in the 18 Gy group was smaller (P<0.05). Conclusions 192lr endovascular irradiation may prevent restenosis after balloon angioplasty. The effect is related to the delivered dose. The mechanism is involved in inhibition of neointimal proliferation. Chin Med J 2001; 114(1): 62-63

Objective To assess the efficacy and safety of intracoronary stenting in the acute phase of unstable angina pectoris (UAP). Methods Fifty-five patients with UAP were randomized to early (Group Ⅰ, n=29) and delayed interventional treatment (Group Ⅱ, n=26). Coronary angiography and stenting were performed within 48hours in Group I and 7-10 days later in Group Ⅱ . Procedural success rate, time interval from admission to angina relief and duration of hospitalization were recorded. Cardiac events within 30 days were observed as well. Results Clinical characteristics and angiographic features were similar between the two groups. There was no significant difference in the procedural success rate (93%versus 96%), but the cardiac event rate within 30 days was significantly lower in Group I than in Group Ⅱ (0%versus 9.2%, P <0.05). The time interval from admission to angina relief (4.4 ± 3.1 days versus 5.7 ± 2.9 days) and the duration of hospitalization (8.8 ± 3.2 days versus 13.5 ± 3.1 days) were significantly reduced in Group Ⅰ(both P<0.05). Conclusions Intracoronary stent implantation is effective and safe in the acute phase of UAP. Early percutaneous coronary intervention results in rapid improvement in symptomatology and a shorter hospitalization. Its long-term effect has to be confirmed in a future randomized study. Chin Med J 2001; 114(1): 59-61

Objective To evaluate the clinical application of helical CT multiplanar reformation (MPR), three-dimensional reconstruction (3D) and virtual laryngoscopy (CTVL) in laryngeal and hypopharyngeal carcinoma. Methods Axial helical CT scans were performed in 22 patients with laryngeal or hypopharyngeal carcinoma, along with MPR, 3D and CTVL. These results were compared with the findings of fiber optic laryngoscopy and surgery. Results Combining axial and MPR images, both the accuracy in preoperative tumor staging and the diagnosis of metastatic lymph nodes were 95%. MPR demonstrated more information about the extent of tumor than axial images in 23%cases; 3D image displayed clearly the extension of tumor, the vessels and airway from multiple views. The location, size and extent of tumors found in cranio-caudal CTVL corresponded well with that of laryngoscopy, and CTVL demonstrated the relationship between the tumor and vocal cords and anterior commissure by caudo-cranial approach, which was inaccessible to fiber optic laryngoscopy in 3 cases. Conclusions Axial images of helical CT clearly demonstrate the location, size and extent of laryngeal and hypopharyngeal carcinoma, while MPR and 3D images are useful in displaying the three-dimensional images and anatomical relation of the tumor. CTVL can clearly display the mucosal surface structures of the larynx and hypopharynx and is a good complementary method of laryngoscopy. Chin Med J 2001; 114(1): 54-58

Objective To get insight on the regulatory mechanism of Ki-67 gene expression in malignant cell cycle. Methods Non-radioactive in situ hybridization (ISH) was undertaken, combined with immunohistochemistry to study the Ki-67 gene transcription and translation in various human cells and tissues. HeLa cells and fresh colon cancer cells, tonsil, normal pancreas and pancreatic cancer tissues were used in this study. A 435 bp cDNA fragment located in exon 13 of the Ki-67 antigen gene was amplified by polymerase chain reaction (PCR). Digoxigenin-labelled antisense and sense RNA probes were prepared for detecting Ki-67mRNA, combined with MIB-1 immunohistochemistry. Results Successful localization of Ki-67 mRNA in human HeLa cells, colon cancer cells, tissues specimen of the tonsil and pancreatic cancer tissue sections was accomplished by digoxigenin-labelling in situ hybridization technique. ISH to colon cancer cells and pancreatic cancer tissue slides showed that much stronger cytoplasm and perinuclear mRNA signals of the Ki-67 gene were present in malignant cells than in normal cells, which was in accordance with MIB-1 nuclear protein signals. Conclusions A sensitive and practical in situ hybridization method for the analysis of Ki-67 antigen mRNA in human cell and tissue was developed. Abnormal transcription of exon 13 of Ki-67 gene might be responsible for malignant cell proliferation in colon and pancreatic cancer. Chin Med J 2001; 114(1): 48-53

Objective To study the histopathologic features and pathogenesis of mucosa-associated lymphoid tissue lymphoma (MALT-oma) of salivary glands. Methods Clinical data, paraffin-embedded sections, immunohistochemical slides (SP method) and electron microscopic features of surgical specimens of 32 cases of salivary gland MALT-oma were studied. Results The patients were 27 males and 5 females, with a mean age of 54.76 years. The lesions were located in the parotid area in 17 cases, and in the submandibular gland in the remaining 15 cases. Much of the MALT-oma was replaced by infiltration of a great amount of centrocyte-like cells (CCL) as background and occasional large cells (centroblast- or immunoblast-like). In MALT-omas "lymphoepithelial lesions" were present. Immunohistochemically, CD20 expression was found to be positive and CD45RO expression was negative in all MALT-omas. Conclusion Most of the MALT-omas are low grade malignant tumors and have a "homing back" phenomenon. The cases were managed by surgery and chemotherapy. In a few MALT- omas which turned into high grade malignant tumors, the prognosis was poor. Acquired MALT may develop as a reaction to autoimmune disease and infection. Hyper-immune reaction and MALT hyperplasia under stimulation may result in myoepithelial sialadenitis and lead to MALT-oma of the salivary gland. Chin Med J 2001; 774(7): 44-47

Purpose To investigate the role of cationic antimicrobial protein of Mr 37 kDa (CAP37) a neutrophil-derived inflammatory mediator on endothelial cell function. Data sources Endothelial cells used in this study were obtained from human lung microvessels and rat aorta. The latter was a kind gift of Dr. Paula Grammas. The mono-mac 6 cell line used in this study was the generous gift of Dr. H.W. Loms Ziegler-Heitbrock. Study selection and data extraction Endothelial cell proteins kinase C activity was determined by measuring calcium- and phospholipid-dependent phosphorylation of histone. Endothelial cell migration was determined using Costar™ Transwell apparatus. Cell surface expression of adhesion molecules, ICAM-1and PECAM-1 was determined using flow cytometry. RT-PCR was used to amplify the CAP37 from endothelial cells treated with LPS . Results We demonstrated that CAP37 which was originally identified as having potent antimicrobial activity and chemotactic activity for monocytes was capable of modulating endothelial cell functions. CAP37activated endothelial cell protein kinase C in a dose- and time-dependent fashion. Importantly CAP37increased the adhesive properties of the endothelium for monocytes. CAP37 upregulated the well known adhesion molecules, ICAM-1 and PECAM-1 in a dose- and time- dependent manner. In addition, CAP37promoted endothelial cell migration. Further investigations indicated that CAP37 was induced in endothelial cells in response to pro-inflammatory cytokines such as tumor necrosis factor-α and interleukin-1α as well as inflammatory mediators such as lipopolysaccharide. Unstimulated endothelial cells did not constitutively express CAP37. The cDNA sequence of endothelial CAP37 was determined and found to be highly homologous to the sequence obtained for neutrophil-derived CAP37. Conclusions Our studies strongly suggest that CAP37 plays a pivotal role in monocyte-endothelial interactions and the transmigration of monocytes from the vasculature into extravascular tissues. Chin Med J 2000; 114(1): 9-13

Objective To compare the endocytic routes of exogenous antigen between murine dendritic cells (DCs)and macrophages (Mϕs). Methods Murine bone marrow-derived DCs and peritoneal Mϕs were pulsed with horseradish peroxidase(HRP)-5 nm colloidal gold for 10 minutes, then grouped and chased for 0-120 minutes in culture medium. Intracellular distribution of 5 nm colloidal gold was explored by means of the cellular enzymatic-chemistry of acid phosphatase and MHC Ⅱ immuno-cytochemistry under electron microscope. Results After 10 minutes of pulse with HRP-5 nm colloidal gold and 30 minutes of chase, most HRP-5 nm gold particles internalized by DCs entered into MHC class Ⅱ compartments (MⅡCs), and a small portion entered into acid phosphatase-positive lysosomes. In contrast to DCs, most Mϕs lysosomes were accessed by HRP-5 nm gold particles, and a small portion of HRP-5 nm gold particles entered into M Ⅱ Cs. After 60minutes of chase, 5 nm gold particles could hardly be seen within Mϕs, whereas most 5 nm gold particles were still retained in DCs. Conclusions The endocytic route of exogenous antigen in DCs seems to be different from that in Mϕs. Antigens taken by Mϕs mainly enter into lysosomes within 30 minutes. In the case of DCs, most internalized antigens enter into MⅡCs, which may be related to their unique antigen-presenting function. In addition, Mϕs seem to have more powerful capacity to scavenge exogenous antigen than DCs. Chin Med J 2001; 114(1): 93-96

Objective To investigate the prevalence of significant enterococcal isolates from urine and determine what factors are associated with the increased prevalence, with particular reference to antibiotic susceptibilities. Methods Retrospective analysis over an 8-year period of hospital laboratory records of urinary isolates of enterococci was done. Species were identified via colony morphology, growth in 6.5%sodium chloride and their ability to hydrolyze esculin in the presence of 40%bile salts. Susceptibility testing via the disc diffusion technique with 9 commonly used antibiotics was also done as defined by the National Committee for Clinical Laboratory Standards. Results From 39 881 urine specimens, 9116 (22.9%) were culture positive. Of this 9116, 1001(11.0%) were enterococci, the 4th most common urinary isolate. E. coli was the most common(36.2%). Most enterococci were from pediatric patients (28.4%) and the urology unit (24.5%). All enterococci were fully sensitive to ampicillin and augmentin (amoxicillin-clavulanic acid) . Sensitivity to gentamicin decreased significantly from 79%in 1990 to 58%in 1997 (P <0.005) . Sensitivity to the cephalosporins and nitrofuratoin were relatively stable, but sensitivity to nalidixic acid varied. No resistance to vancomycin was detected during the study, and no cases of bacteremia complicated bacteriuria were seen. Conclusion Isolation of enterococci was relatively stable during the 8-year period, and all isolates were fully sensitive to the older β-lactams^ ampicillin, cefaclor and augmentin, but displayed varying degrees of multi-resistance to other commonly used urinary agents such as nalidixic acid and co-trimoxazole(trimethoprim-sulfamethoxazole). Because of the emergence of multi-resistant enterococci in many countries and the high cost of drugs in our society, it is imperative that vigilance be maintained in monitoring enterococcal infections in hospitals. Chin Med J 2001; 114(1): 90-92

Objective To study the pathologic features of occult lymphatic metastasis in supraglottic carcinoma. Methods Serial sections of 153 neck dissection specimens in 100 patients with supraglottic carcinoma were evaluated under the microspcope. Results In 100 patients, 38 had occult metastatic lymph nodes. 51 metastatic lymph nodes were found in pathology, and their sizes ranged from 0.5 cm to 2.6 cm (average 1.1 cm). The distribution of 51 lymph nodes was 1 in level I (2%), 37 in level Ⅱ (73%), 12 in level Ⅲ (24%), and 1 in level N (2%). Among the 51 nodes, 21 (41 %) were early stage, 18 (35%) were growth stage, 7 (14%) were tull stage, and 5 (10%) were extracapsular stage. The differentiation degree and appearance of supraglottic carcinoma was not directly related with occult metastasis. Conclusion The occult metastatic rate of supraglottic carcinoma is high, and selective neck dissection may be necessary. Chin Med J 2001; 114(1): 88-89

Purpose and Methods Open-heart surgery with the use of cardiopulmonary bypass (CPB) is associated with an inflammatory cascade which contributes to the development of postoperative complications including multiple organ failure. To provide an update on the subject, we briefly review the recent English-language literature. Results During CPB, various factors have been recognized to induce a complex inflammatory response. Based on an enhanced understanding of the underlying mechanisms, therapeutic strategies have been developed to reduce this inflammatory reaction and its subsequent damaging effects. Off-pump coronary artery bypass grafting may result in less inflammatory injury as compared with the conventional maneuver,which can in turn, diminish the incidence of cardiac, renal, or neurological dysfunction. It is also clear that improving the biocompatibility of CPB materials can lead to a better patient recovery. Inasmuch as the pathophysiology involved appears to be multifactorial, it is unlikely that a single intervention could achieve the desired goal. Both pharmacologic strategies, such as steroid pretreatment, and modification of mechanical devices, such as the use of heparin-coated CPB circuits, could have important clinical implications. The balance between pro- and anti-inflammatory responses may be crucial in limiting the extent of inflammatory injury. Conclusions To date, the concept of organ protection should no longer be limited to the individual organ. Instead, investigations must be extended to focus on a systemic level. Chin Med J 2001; 114(1): 3-8