Changes in expression of N-methyl-D-aspartate receptor subunits in the rat neostriatum after a single dose of antisense oligonucleotide specific for N-methyl-D-aspartate receptor 1 subunit

In order to investigate the process of gene expression of N-methyl-D-aspartate glutamate receptor (NMDAR) subunits in the rat neostriatum and how this relates to motor behaviors, a single dose of antisense phosphodiester oligodeoxynucleotide specific for NMDAR1 was unilaterally applied in the neostriatum in a stereotaxic apparatus. After one day of antisense treatment, ipsilateral rotation behaviors that were induced by apomorphine were found in the treated animals. Reductions in the levels of expression of NMDAR1 and NMDAR2A messenger RNAs (NMDAR1: 20.6%; NMDAR2A: 19.7%) were found in the antisense-treated striatal tissues by reverse transcriptase-polymerase chain reaction. There was no change in the levels of NMDAR2B, NMDAR2C and NMDAR2D messenger RNAs. After two days, western blotting experiments showed that there were decreases in the levels of expression of NMDAR1 (decreased 27.6%) and NMDAR2A (decreased 19.2%) proteins in the NMDAR1 antisense-treated striatal tissues. In addition, NMDAR1 immunoreactivity was found to decrease in intensity in the NMDAR1 antisense-treated neostriatum. At the cellular level, the intensity of NMDAR1 immunoreactivity in perikarya of presumed medium spiny neurons was found to decrease. These results indicate that a single dose of NMDAR1 antisense modifies the expression of NMDAR1 messenger RNA and protein in neurons in the neostriatum. The modification in the expression of NMDAR1 has differential effects in the expression of NMDAR2 subunits. Gene expression of the native NMDAR subunits is likely to be a dynamic process. The change in gene expression of the NMDAR subunits in the neostriatum may have a profound effect on the motor behaviors of rats.

Thyroid nodules: rational management

Thyroid nodules are the commonest disorder presenting to the endocrine surgeon. Most of the lesions are benign, but the principal problem facing the clinician is that of identifying the malignant nodule requiring surgery. Current diagnostic methods are reviewed, and the role of intraoperative frozen section in particular is examined in a series of 155 patients undergoing thyroidectomy for solitary thyroid nodule. It is concluded that when the fine-needle aspiration cytology (FNA) result is malignant intraoperative frozen section is unnecessary and contributes little to the management. Frozen section, however, is considered to be of value when the FNA result is reported as benign, suspicious, or inadequate. It permits identification of many malignant lesions that would otherwise require a second operation to complete a total thyroidectomy. Details of the indications for surgery and the operative strategy are discussed.

A study of secondary cutaneous amyloidosis in basal cell carcinoma in Chinese patients: lack of correlation with bcl-2 or p53 protein expression

Pigmented basal cell carcinoma (BCC) is an uncommon form of BCC among Caucasians. In contrast, the majority of BCC in Orientals are pigmented BCC. To assess the occurrence of secondary amyloid deposits in BCC among Chinese patients, a retrospective study was conducted on 53 BCC specimens. We used a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling method for detecting the apoptotic cells. In addition, immunohistochemical staining was performed to examine the expression of the B-cell leukemia/lymphoma-2 gene (bcl-2) and p53 protein. Of the 53 BCC specimens, 37 (69.8%) were pigmented BCC and 31 (58.5%) showed amyloid deposits in the stroma of the tumor cells. The mean percentage of apoptotic tumor cells was 0.29%. Immunostaining of bcl-2 and p53 was detected in 33 BCCs (62.3%) and 19 BCCs (35.8%), respectively. No relationship between amyloid deposition and the number of apoptotic cells was found. In addition, there was no correlation between amyloid deposition and bcl-2 protein expression or between amyloid deposition and p53 protein expression. Our results indicate that the frequency of secondary amyloidosis in BCC among Chinese patients is not higher than that reported in the West. Although no correlation could be detected between amyloid deposition and bcl-2/p53 protein expression, the possible role of apoptosis in the pathogenesis of amyloid deposition in BCC still needs further investigation.

Heavy metal concentrations in green-lipped mussels collected from Tolo Harbour and markets in Hong Kong and Shenzhen

Green-lipped mussels, Perna viridis, were collected from Kat O, Yim Tin Tsai, Ma Liu Shui and Tap Mun around Tolo Harbour and six local markets in Hong Kong (Aberdeen, Shau Kei Wan, Kowloon City, Mongkok, Yuen Long) and Shenzhen (Dongmun) between July 1994 and February 1995 and analysed for cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn). The metal concentrations of mussels collected from the study sites were Cd (0.45-1.44 microg/g), Cr (0.82-4.89 microg/g), Cu (6.02-23.99 microg/g), Ni (3.25-6.87 microg/g), Pb (2.02-4.36 microg/g) and Zn (90-135 microg/g), while those from the markets were Cd (0.27-1.44 microg/g), Cr (1.09-3.30 microg/g), Cu (9.05-17.8 microg/g), Ni (2.44-5.25 microg/g), Pb (1.17-5 microg/g) and Zn (51-103 microg/g). The metal concentrations were below the maximum permissible levels set by the Hong Kong Government. In addition, seasonal variation of metal accumulation in mussels was investigated in Yim Tin Tsai and Ma Liu Shui and a reduction in the total heavy metal concentrations during winter was noted. The non-carcinogenic hazard index of mussels collected from Tolo Harbour and from Hong Kong markets was between 0.46 and 1.36 compared with those from Shenzhen markets (0.85-1.46), which indicated a low but possible risk in consuming the mussels.

Protective effects of seaweeds against liver injury caused by carbon tetrachloride in rats

Three species of seaweeds collected from Tung Ping Chau, Hong Kong, were screened for their hepatoprotective activity using carbon tetrachloride (CCl4)-induced liver injury in the rat as a model of chemical hepatitis. A single oral dose of 1.25 ml/kg of CCl4 was able to produce significantly elevated levels of serum glutamic pyruvic transaminase (GPT) and glutamic oxaloacetic transminase (GOT). Administration of 150, 300 and 600 mg/kg of aqueous extracts from Myagropsis myagroides, Sargassum henslowianum and S. siliquastrum, respectively, significantly reduced the CCl4-induced acute elevation in the levels of GPT and GOT in rats. The same result was also seen in the histopathological study of liver tissue. The seaweed crude extracts probably acted to protect against CCl4-induced liver injury through their antioxidant properties.

Ecotoxicological assessment of persistent organic and heavy metal contamination in Hong Kong coastal sediment

The aim of the present project is to determine the feasibility of measuring hepatic cytochrome P4501A1 (CYP1A1) and metallothionein (MT) mRNA in fish as an integrative measurement of persistent organic pollutants (POPs) and heavy metal contamination in sediment arising in Hong Kong. Sediment samples were collected from different sites, including Victoria Harbour (VS6), Yim Tin Tsai (YTT) at Tolo Harbour, Mai Po marshes (MPM) at Deep Bay, and Southern Waters (SS6) of coastal waters. The samples were analyzed for total and extractable concentrations of Cd, Cu, Ni, Zn, and Pb, as well as PCBs and PAHs. In addition, biomarker responses were studied in tilapia exposed experimentally to coastal sediment for 7 days. Using RT-PCR technique, hepatic CYP1A1 and MT mRNA were measured. Three control groups were used, including one negative control group maintained in sea water only; the second and third positive control groups were in sea water but were intraperitoneally injected with either beta-naphthoflavone (40 microg/g body weight) or cadmium chloride (10 microg/g body weight), respectively. The chemical data showed that VS6, YTT, and MPM were classified as Class C sediment according to the sediment quality criteria defined by the Hong Kong Environmental Protection Department, indicating the sites were heavily polluted. The exposure of tilapia to the sediment induced hepatic CYP1A1 (VS6 > YTT > MPM > SS6) and MT (VS6 > MPM > YTT > SS6) levels. The induction patterns were comparable to the levels of POPs and metal contamination in the sediment, indicating that the biomarker responses could be used to differentiate low to high levels of contamination among sediment.

Morphological and biochemical changes in the gills of Tilapia (Oreochromis mossambicus) to ambient cadmium exposure

Tilapia, Oreochromis mossambicus, were reared in freshwater and exposed to 40, 80 and 160 ppb ambient cadmium for a period of 7 days to investigate the effects of short-term Cd exposure on the cellular function of gill chloride cells. Gills were sampled after 3 and 7 days exposure. The accumulated Cd concentration in gills was analyzed using a graphite furnace atomic absorption spectrophotometer while the morphological changes of pavement and chloride cells were examined using scanning and transmission electron microscopes. Gill Cd concentration was significantly increased in samples (10.03-44.36 ppb) at 3 and 7 days exposure. Accompanying this was an augmentation of microridge in pavement cells, and an increase in the density (1964-3603 /mm(2)) and apical membrane area (11.57-46.32 µm(2)) in chloride cells, indicating an adaptational modification of the cell morphology in assisting gaseous transfer and Ca(2+) uptake, respectively. However, biochemical analyses of the gill tissues enumerated a decrease in both the activities of alkaline and high-affinity Ca(2+)-ATPases. This indicated a reduction in the Ca(2+)-transport capacity per unit chloride cell, suggesting chloride cells being the primary target of Cd which subsequently lead to fish hypocalcemia.

Sodium salicylate-induced apoptosis of human peripheral blood eosinophils is independent of the activation of c-Jun N-terminal kinase and p38 mitogen-activated protein kinase

BACKGROUND

It has been shown that the inhibition of eosinophilic apoptosis is an important mechanism for the development of blood and tissue eosinophilia in allergic diseases. Considerable attention has recently been focused on the role played by different intracellular kinase cascades in the control of apoptosis. In the present study, we investigated the effect of sodium salicylate (NaSal), a nonsteroidal anti-inflammatory drug, on mitogen-activated protein kinases (MAPK) and apoptosis of human eosinophils.

METHODS

Human blood eosinophils were purified from buffy coat. NaSal-induced apoptosis of eosinophils was assessed by morphological changes and Annexin-V binding assay. Changes of MAPK activity upon treatment with NaSal were measured by kinase activity assay and Western blot.

RESULTS

NaSal could induce apoptosis of human blood eosinophils in a dose- and time-dependent manner. It could also activate c-Jun N-terminal kinase (JNK) and p38 MAPK but not extracellular signal-regulated protein kinase (ERK) activity within 1 h. Pretreatment of eosinophils with p38 MAPK and JNK anti-sense (AS) phosphorothioate oligodeoxynucleotides (ODN) or specific p38 MAPK inhibitor SB 203580 did not have any significant effect on NaSal-induced apoptosis. However, ERK AS ODNs could trigger the apoptosis of normal eosinophils.

CONCLUSION

There is no direct relationship between the activation of JNK and p38 MAPK pathways and NaSal-induced apoptosis in human peripheral blood eosinophils.

Bovine adrenal 3beta-hydroxysteroid dehydrogenase (E.C. 1.1.1. 145)/5-ene-4-ene isomerase (E.C. 5.3.3.1): characterization and its inhibition by isoflavones

The isoflavones daidzein, genistein, biochanin A and formononetin inhibit potently and preferentially the gamma-isozymes of mammalian alcohol dehydrogenase (gammagamma-ADH), the only ADH isozyme that catalyzes the oxidation of 3beta-hydroxysteroids. Based on these results, we proposed that these isoflavones might also act on other enzymes involved in 3beta-hydroxysteroid metabolism. Recently, we showed that they indeed are potent inhibitors of a bacterial beta-hydroxysteroid dehydrogenase (beta-HSD). To extend this finding to the mammalian systems, we hereby purified, characterized and studied the effects of isoflavones and structurally related compounds on, a bovine adrenal 3beta-hydroxysteroid dehydrogenase (3beta-HSD). This enzyme catalyzes the oxidation of 3beta-hydroxysteroids but not 3alpha-, 11beta- or 17beta-hydroxysteroids. The same enzyme also catalyzes 5-ene-4-ene isomerization, converting 5-pregnen 3, 20-dione to progesterone. The K(m) values of its dehydrogenase activity determined for a list of 3beta-hydroxysteroid substrates are similar (1 to 2 microM) and that of its isomerase activity, determined with 5-pregnen 3, 20-dione as a substrate, is 10 microM. The k(cat) value determined for its isomerase activity (18.2 min(-1)) is also higher than that for its dehydrogenase activity (1.4-2.4 min(-1)). A survey of more than 30 isoflavones and structurally related compounds revealed that daidzein, genistein, biochanin A and formononetin inhibit both the dehydrogenase and isomerase activity of this enzyme. Inhibition is potent and concentration dependent. IC(50) values determined for these compounds range from 0.4 to 11 microM, within the plasma and urine concentration ranges of daidzein and genistein of individuals on vegetarian diet or semi-vegetarian diet. These results suggest that dietary isoflavones may exert their biological effects by inhibiting the action of 3beta-HSD, a key enzyme of neurosteroid and/or steroid hormone biosynthesis.

Conceptualization, reporting and underreporting of child abuse in Hong Kong

OBJECTIVE

To understand the conceptualization of child abuse and attitudes on reporting behaviors of Hong Kong adults.

METHODS

Cross-sectional telephone survey of 1,001 randomly selected subjects.

MAIN RESULTS

There is a discrepancy between perceived prevalence and the ability to name different child abuse types without prompting: 79.9% named physical abuse, while 41.2% felt it was common: 21.0% named child neglect, while 76.9% felt it was common; 13.4% named psychological abuse, while 47.4% felt it was common; 6.8% named sexual abuse, while 23.5% felt it was common. Most respondents classified severe physical abuse situations as abusive (e.g., "severely injuring a child"). Other scenarios such as "mildly injuring a child" and neglect and psychological abuse scenarios (e.g., "leaving a young child alone at home" and "shouting at a child often") were often not classified as abusive. As regards case-reporting behavior, only about 40% would report abuse cases to authorities. Those who would not report abuse were less likely to classify abuse situations as abusive and more likely to think that seeking help is difficult, troublesome and unhelpful.

CONCLUSIONS

The official reported prevalence figures for child abuse in Hong Kong should be interpreted with care, because underreporting is likely to be serious. Hong Kong people's conceptualization and awareness of what comprises child abuse is found to differ from official definitions. They are reluctant to report abuse cases, due to their perceived low efficacy of case reporting. Both the difference in conceptualization and the reluctance to report might partly be attributable to Chinese culture.

Opposing effects of sodium salicylate and haematopoietic cytokines IL-3, IL-5 and GM-CSF on mitogen-activated protein kinases and apoptosis of EoL-1 cells

Haematopoietic cytokines such as IL-3, IL-5 and GM-CSF not only activate eosinophils but also prolong their life span by inhibiting their apoptotic cell death. We have studied the effects of IL-3, IL-5 and GM-CSF on apoptosis and mitogen-activated protein kinases (MAPKs) in a human eosinophilic leukaemic cell line (EoL-1). Results demonstrated that all three cytokines could trigger the receptor-mediated activation of extracellular signal-regulated kinase (ERK) within one hour but not p38 MAPK activity in EoL-1 cells. In contrast, sodium salicylate (NaSal), a nonsteroidal anti-inflammatory drug (NSAID), could activate p38 MAPK but not ERK within one hour. Both cytokines and specific p38 MAPK inhibitor SB 203580 could partly block the NaSal-induced apoptosis in EoL-1 cells. A specific MAPK/ERK kinase (MEK) inhibitor, PD 098059, could induce apoptosis and eliminate the protective effect of IL-3, IL-5 and GM-CSF against NaSal-induced apoptosis in EoL-1 cells. Taken together, cytokines IL-3, IL-5 and GM-CSF could prolong EoL-1 cells survival through the transient activation of ERK. On the other hand, activation of p38 MAPK in EoL-1 cells by NaSal could lead to apoptosis. Activation of p38 MAPK and the resulting induction of apoptosis in EoL-1 cells may be important to explain the anti-inflammatory action of NSAID in allergic inflammation.

Glucose-dependent insulinotropic polypeptide gene expression in the stomach: revealed by a transgenic mouse study, in situ hybridization and immunohistochemical staining

Glucose-dependent insulinotropic polypeptide (GIP) plays an important role in stimulating insulin release in the pancreas as well as inhibiting gastric acid secretion in the stomach. GIP has been found in specific endocrine cells located in the mucosal layer of the small intestine and in the submandibular salivary gland. In this study, the tissue-specific expression of GIP guided by 1.2 kb of the human GIP (hGIP) gene 5' flanking region was investigated by a transgenic mouse approach. A chimeric promoter-reporter gene construct linking the 5'-flanking region of the hGIP gene with the thymidine kinase gene of the herpes simplex virus was introduced into the genomes of mice by microinjection. By reverse transcriptase-PCR (RT-PCR) and thymidine kinase assays, transgene expression was found in the stomach and pancreas. The enzyme activity detected in the stomach was about 6-fold higher than that found in the pancreas, suggesting that GIP may be expressed in the stomach. This observation is supported by RT-PCR studies since both human and mouse GIP transcripts are detected in the stomach and small intestine. In addition, distinct GIP-producing cells were identified in both tissues in mouse by in situ hybridization and immunohistochemical staining. Taken together, our data demonstrate for the first time that GIP is expressed in human and mouse stomach.

Four-year survival of patients with acute coronary syndromes without ST-segment elevation and prognostic significance of 0.5-mm ST-segment depression

We prospectively evaluated all patients admitted to our coronary care unit during 1993 with ischemic chest pain but without ST-segment elevation on the presenting electrocardiogram, and determined the influence of the extent of ST-segment depression, measured using calipers and blinded to the outcome, on 4-year survival. The presenting symptoms of 367 patients (mean age 64 years) were coded according to the Braunwald classification, 86% being in class IIIB (primary unstable angina with rest angina within 48 hours) and 7.4% in class IIIC (postinfarction angina). Thirty-two patients (8.6%) had myocardial infarction at presentation (defined as a creatine kinase level exceeding twice the reference range within 18 hours). During hospitalization 97% of patients received aspirin, 67% received intravenous heparin, 37% underwent angiography, and 35% underwent revascularization. The vital status of 99% of the patients was determined after a median of 52 months (interquartile range 48 to 55). At follow-up, 88% of patients were taking aspirin, 45% were taking beta blockers, and 50% had undergone revascularization. The survival rate was 70% in patients with > or = 0.5-mm ST-segment depression (53%, 77%, and 82% survival for > or = 2-, 1-, and 0.5-mm ST-segment depression, respectively; p <0.0001). Patients with a normal electrocardiogram had a greater survival rate (94%) than that of patients with 0.5-mm ST-segment depression (82%, p = 0.020), but not significantly different from that of patients with T-wave inversion (84%, p = NS). Independent predictors of mortality (odds ratio [95% confidence interval]) were: age in yearly increments (1.05 [1.03 to 1.06], p = 0.003), revascularization during follow-up (0.40 [0.29 to 0.56], p = 0.006), pulmonary edema (3.45 [2.19 to 5.45], p = 0.007), and ST-segment depression (1.37 [1.20 to 1.55], p = 0.015). Thus, ST-segment depression of > or = 0.5 mm predicts 4-year survival in patients with acute ischemic syndromes.

Chloride cell subtypes in the gill epithelium of Japanese eel Anguilla japonica

The purpose of the present study was to characterize chloride cell subtypes in the fish gill and to monitor the kinetic change of cell division in the gill epithelia during seawater adaptation. Employing a three-step Percoll gradient method, the gill chloride cells and nonchloride cell population were isolated. The isolated cells were studied using multiparameter flow cytometry, recording the changes in 1) cell size, 2) cellular granularity, and 3) cell autofluorescence. Two chloride cell subtypes were identified in the freshwater eels. Within 2-4 days after entering seawater, new subtypes of transitory chloride cell, with bigger cell size and more intense mitochondria autofluorescence, appeared. After full adaptation, two major seawater chloride cell subtypes were again discerned; their sizes were the largest and their mitochondria autofluorescence was the highest. In the second part of the experiment, cell cycle analysis demonstrated a progressive increase in the percentage of gill cells entering the DNA synthesis phase during seawater adaptation, where a small population of mitotic cells was identified in the nonchloride cell population but not in chloride cells. We hypothesize that the mitotic cells identified are stem cells, which will ultimately differentiate into seawater chloride cells. Our results confirm the existence of heterogeneity of chloride cells. Individual subtypes could be isolated in high purity for further studies to elucidate their respective function in mediating ion transport.

Trinucleotide CGG repeat in the FMR1 gene in Chinese mentally retarded patients

The fragile X syndrome of mental retardation is related to the number of trinucleotide CGG repeats at the 5'-untranslated region of the FMR1 gene located on the X-chromosome. We have studied X-chromosomes from 649 unaffected Chinese subjects and 324 patients with mild mental retardation. All study subjects were unrelated. The CGG repeat number was analysed by electrophoresis of a polymerase chain reaction followed by gel transfer and hybridisation with a 32P-labeled (CCG)5 probe. The DNA samples having detectable CGG expansion were further analysed by Southern blot analysis with probe StB12.3 after restriction digestion by EcoR I and Eag I. For the unaffected Chinese subjects, a different distribution pattern of CGG allele size from Caucasians was observed. It was a bimodal pattern and the CGG repeat number ranged from 19 to 54. The most common CGG repeat allele was 29 compared with 30 in Caucasians. The second mode appeared at 36 repeats. There was mild statistical difference in the repeat patterns between the mentally retarded patients and unaffected subjects, although the essential features were similar. Among the mentally retarded patients, one male had an unmethylated full mutation and one female had a full mutation. The fragile X prevalence was 0.6%, which is lower than two previous studies in Chinese mentally retarded patients utilising cytogenetic analysis. Our results indicate that a large-scale screening program would be worthwhile to determine the prevalence of the fragile X syndrome in the Chinese population.

Subpopulations of neurons in the rat neostriatum display GABABR1 receptor immunoreactivity

Immunoreactivity for gamma aminobutyric acid BR1 receptor (GABABR1) was detected in the neuropilar elements as well as in the perikarya of neurons in the neostriatum. Many of the GABABR1-immunoreactive perikarya were medium-sized with a thin rim of cytoplasm. They resembled the morphology of medium spiny neurons, the projection neurons of the neostriatum. In addition, some GABABR1-immunoreactive neurons were densely labeled and were of medium to large in size. These neurons were characterized by double immunofluorescence using their neurochemicals as markers. Over 90% of the parvalbumin- and choline acetyltransferase-immunoreactive neurons and about 80% of the nitric oxide synthase-immunoreactive neurons displayed GABABR1 immunoreactivity. The present results show for the first time that the major four subpopulations of striatal neurons express GABABR1 receptor and may have a functional implication in the GABA neurotransmission in the microcircuitry of the neostriatum.

Prevalence and correlates of physical abuse in Hong Kong Chinese adolescents: a population-based approach

OBJECTIVE

The objectives were to estimate the prevalence and correlates of physical abuse-related outcomes in the family setting in Hong Kong's adolescent population.

METHOD

A cross-sectional study design was used. A randomly selected sample of 3,355 secondary school students in Kwai Tsing District of Hong Kong was surveyed. The response rate was 98%.

RESULTS

The prevalence rates of corporal punishment, being beaten by parents for no apparent reason, being beaten to injury by family members in the past 3 months and any one of the above three were 4.9% (95% CI, 4.2% to 5.6%), 2.0% (95% CI, 1.5% to 2.5%), 1.1% (95% CI, .98% to 1.2%) and 6.6% (95% CI, 5.7% to 7.5%), respectively. Students who had experienced the above physical abuse-related outcomes were at a significant disadvantage for a wide range of morbidity indicators, including self-perceived bad health, anxiety and stress, somatic illnesses (such as asthma and epigastric pain), injuries and accidents, and hospitalization. They were more likely to have poor familial relations and coping skills, and to take up habits which potentially put their health at risk, such as smoking, alcohol consumption, and fighting with others.

CONCLUSIONS

Our prevalence estimates of physical abuse in the family setting for a student population in Hong Kong is an improvement over previous local estimates of physical abuse occurrence, which were mainly based on case notifications and clinical samples. The results also show that the abused adolescents are growing up in an environment filled with physical, psychological, and familial adversities.

Differentiation of a human eosinophilic leukemic cell line, EoL-1: characterization by the expression of cytokine receptors, adhesion molecules, CD95 and eosinophilic cationic protein (ECP)

Purification of enough eosinophils for the study of allergic inflammation is difficult because eosinophils comprise only a small percentage of circulating leucocytes. A human eosinophilic leukemic cell line, EoL-1, has been considered to be an in vitro eosinophilic model. In the present study, the suitability of EoL-1 cells as an eosinophilic model was further investigated. EoL-1 cells were induced to differentiate by dibutyryl cyclic AMP (dbcAMP). The expression of cell surface cytokines (IL-3, IL-5, GM-CSF) receptors, adhesion molecules (CD49d, CD11b), and CD95 (Fas) was investigated by flow cytometry. Expression of eosinophilic cationic protein (ECP) was determined by fluorescence enzyme immunoassay (FEIA) and reverse transcription-polymerase chain reaction (RT-PCR). EoL-1 cells could be differentiated into eosinophilic vacuole-containing cells by dbcAMP. They were found to express cell surface IL-3 and GM-CSF receptors, CD95 and CD49d. Treatment with dbcAMP could induce the expression of CD11b but decrease the expression of CD95. Anti-CD95 antibody could induce their apoptosis. The differentiation of EoL-1 cells was accompanied by increase in release of ECP into the supernatant and total ECP synthesis. Differentiation of EoL-1 cells also up-regulated the expression of mRNA for ECP and its level was parallel to the total amount of ECP synthesis. By virtue of their expression of haematopoietic cytokines receptors, adhesion molecules, CD95, synthesis and release of ECP, EoL-1 cells are suitable as an in vitro eosinophilic model for studying eosinophilic functions.

FRAXAC1 and DXS548 polymorphisms in the Chinese population

The fragile X syndrome is the most common inherited form of mental retardation. Haplotype studies using FRAXAC1 and DXS548 polymorphic markers flanking the fragile site have demonstrated linkage disequilibrium at the FMR1 locus. We investigated the association of the FRAXAC1, DXS548 and CGG alleles between normal subjects and mentally retarded (MR) patients of unspecified cause who do have fragile X syndrome. We have evaluated the FRAXAC1 site in 390 normal subjects and 321 MR patients and the DXS548 site in 146 normal and 319 MR subjects. Both FRAXAC1 and DXS548 alleles were determined by application of the polymerase chain reaction. When compared with Caucasians, the normal Chinese population has a different FRAXAC1 allele distribution. There are more AC18 repeat alleles and fewer AC19 repeat alleles. The DXS548 allele distributions were similar between Chinese and Caucasians. The same distribution pattern of FRAXAC1 alleles was found in both normal subjects and MR patients, but there were significant differences in the distribution patterns of DXS548 alleles. The FMR1 CGG-DXS548 and FRAXAC1-DXS548 haplotype distribution between normal subjects and MR patients also differed significantly. Our results suggest a possible association between DXS548 alleles and non-FRAXA mental retardation.

Isolation of viable cell types from the gill epithelium of Japanese eel Anguilla japonica

High-purity viable cells with low mitochondria (pavement cells) and mitochondria-rich content (chloride cells) were successfully isolated from the gill epithelium of Japanese eels, using three-step Percoll gradient low-speed centrifugation. Cytochemistry (silver staining for chloride, rhodamine-123, and Mitotracker for mitochondria and actin/spectrin immunofluorescence) and scanning electron microscope images were used to identify the cell types in the gill epithelium of the eel. Pavement cells were isolated at 97 and 98% purity for freshwater- and seawater-adapted eels, respectively, and chloride cells were obtained at 89 and 92% purity. The enzymatic activities of the isolated cells were determined. Na+-K+-ATPase, Mg2+-ATPase, and succinate dehydrogenase were found mainly in the chloride cell. Alkaline Ca2+-ATPase and low- and high-affinity Ca2+-ATPase were about twice as high in the chloride cell compared with the pavement cell. Transfer of eels to seawater resulted in enlargement of chloride cell sizes and significant increases in Na+-K+-ATPase, Mg2+-ATPase, and succinate dehydrogenase activities, while all Ca2+-ATPases declined by approximately 60-80%. This is the first report demonstrating the successful isolation of freshwater chloride cells and also an exclusive method of getting high-purity seawater chloride cells. The isolated cells are viable and suitable for further cytological and molecular studies to elucidate the mechanisms of ionic transport.

Apoptosis in primary cutaneous amyloidosis

Amyloid deposits in primary cutaneous amyloidosis (PCA) may be initially derived from cytokeratin. possibly after keratinocyte death. However, the mechanism of keratinocyte death remains obscure. To investigate the potential role of apoptosis in the pathogenesis of PCA, a retrospective study was conducted on the skin tissues from 20 Chinese patients with PCA. We used a terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL) method for detecting the apoptotic cells. Immunohistochemical staining was performed to examine the expression of the B-cell leukemia/lymphoma-2 gene (bcl-2) and Fas. Apoptotic cells were shown in 11 of 20 cases (55%) by TUNEL. Histological sections showed that dyskeratotic cells and vacuolar alteration of the basal cells were more commonly observed in the TUNEL-positive group. In all cases of PCA, epidermal expression of bcl-2 was minimal, while expression of Fas was observed on keratinocytes in the basal to granular layers: however, these findings were not different from those in normal skin. Our results suggest that the keratinocyte destruction in PCA may occur as an initial result of apoptosis, which in turn leads to the amyloid formation.

Usefulness of the presenting electrocardiogram in predicting successful reperfusion with streptokinase in acute myocardial infarction

The presenting electrocardiogram may contain information indicating the probability of successful reperfusion. The relation between 3 parameters in the presenting electrocardiogram (pathologic Q waves, T-wave inversion, and the slope of ST elevation) and Thrombolysis in Myocardial Infarction trial (TIMI) grade 3 flow in the infarct-related artery was assessed angiographically 90 minutes after beginning streptokinase in 362 patients. TIMI grade 3 flow was more common in patients without Q waves (55%) than in those with Q waves (35%; p <0.001), and more common in patients without T-wave inversion (50%) than in those with T-wave inversion (30%; p <0.002). There was no relation between the slope of the ST segment or the magnitude of its deviation and the achievement of TIMI grade 3 flow. Only 20% of the 59 patients with both Q waves and T-wave inversion had TIMI grade 3 flow, compared with 50% of the remaining patients (p <0.0001). Among patients treated within 3 hours, TIMI grade 3 flow was seen in 68% of those without versus 44% of those with Q waves (p <0.01), and in 62% of those without versus 43% of those with T-wave inversion (p = 0.06). Among patients treated after 3 hours, TIMI grade 3 flow was seen in 38% of those without versus 30% of those with Q waves (p = NS), and in 38% of those without versus 23% of those with T-wave inversion (p <0.05). On multivariate analysis, the absence of Q waves, the time from the onset of chest pain to treatment, and age were independent predictors of TIMI grade 3 flow. Pathologic Q waves in the presenting electrocardiogram provide valuable information as to the probability of achieving successful reperfusion following administration of streptokinase, and may be helpful for triage of patients to alternative reperfusion strategies, including percutaneous revascularization.