Treatment of childhood phimosis with a moderately potent topical steroid

BACKGROUND

Recently, topical steroid application has been shown by a small number of studies to be an effective alternative to circumcision for the treatment of phimosis. However, only potent or very potent corticosteroids have been more thoroughly studied in this treatment option. A prospective study was conducted to determine whether comparable results could be achieved using a weaker steroid cream.

METHODS

Boys, 3-13 years of age, with non-retractable foreskin due to a tight ring at the tip were offered the regimen of twice-daily preputial retraction and topical application of 0.02% triamcinolone acetonide cream. The degree of preputial retractability was assessed at presentation and at 4 and 6 weeks of treatment. Success was defined as full retraction or free retraction up to agglutination of the foreskin to the glans.

RESULTS

Eighty-three boys completed the treatment. Successful retraction was achieved in 48/83 (58%) patients after 4 weeks and 70/83 (84%) patients after 6 weeks of application. The overall response rate aggregated from six published series using 0.05% betamethasone was 87% at 4 weeks and 90% on completion of treatment. Thus, the results appear inferior when analysed at 4 weeks but compare favourably with those reported for a more potent steroid on completion of the full course of treatment.

CONCLUSIONS

Even though the triamcinolone cream used in the present study is less potent than the more commonly used 0.05% betamethasone valerate cream, it could effect comparable improvements in foreskin retractability after 6 weeks of treatment.

Proinflammatory cytokines (IL-17, IL-6, IL-18 and IL-12) and Th cytokines (IFN-gamma, IL-4, IL-10 and IL-13) in patients with allergic asthma

Allergen-reactive T helper type-2 (Th2) cells and proinflammatory cytokines have been suggested to play an important role in the induction and maintenance of the inflammatory cascade in allergic asthma. We compared the plasma concentrations of novel proinflammatory cytokines IL-17 and IL-18, other proinflammatory cytokines IL-6 and IL-12, Th2 cytokines IL-10 and IL-13, and intracellular interferon-gamma (IFN-gamma) and IL-4 in Th cells of 41 allergic asthmatics and 30 sex- and age-matched health control subjects. Plasma cytokines were measured by enzyme-linked immunosorbent assay. Intracellular cytokines were quantified by flow cytometry. Plasma IL-18, IL-12, IL-10, IL-13 concentrations were significantly higher in allergic asthmatic patients than normal control subjects (IL-18: median 228.35 versus 138.72 pg/ml, P < 0.001; IL-12: 0.00 versus 0.00 pg/ml, P = 0.001; IL-10: 2.51 versus 0.05 pg/ml, P < 0.034; IL-13: 119.38 versus 17.89 pg/ml, P < 0.001). Allergic asthmatic patients showed higher plasma IL-17 and IL-6 concentrations than normal controls (22.40 versus 11.86 pg/ml and 3.42 versus 0.61 pg/ml, respectively), although the differences were not statistically significant (P = 0.077 and 0.053, respectively). The percentage of IFN-gamma-producing Th cells was significantly higher in normal control subjects than asthmatic patients (23.46 versus 5.72%, P < 0.001) but the percentage of IL-4 producing Th cells did not differ (0.72 versus 0.79%, P > 0.05). Consequently, the Th1/Th2 cell ratio was significantly higher in normal subjects than asthmatic patients (29.6 versus 8.38%, P < 0.001). We propose that allergic asthma is characterized by an elevation of both proinflammatory and Th2 cytokines. The significantly lower ratio of Th1/Th2 cells confirms a predominance of Th2 cells response in allergic asthma.

Effects of dexamethasone on the expression of Fas molecules and apoptosis of lymphocytes in patients with systemic lupus erythematosus

Previous studies have shown that the autoimmune phenomenon could be caused by defective apoptosis of autoreactive lymphocytes. Corticosteroids used for treatment of systemic lupus erythematosus (SLE) are potent apoptosis inducers. We examined dexamethasone (DEX)-induced apoptosis and Fas expression in peripheral blood lymphocytes of SLE patients and normal subjects. Peripheral blood lymphocytes were obtained from 40 SLE patients and 18 sex- and age-matched control subjects. Percentages of apoptosis and expression of Fas molecule in lymphocytes were assessed by flow cytometry. Fas expression in lymphocytes treated with or without DEX was significantly higher in SLE patients than normal controls [median (interquartile range) of mean fluorescence intensity without DEX: 74.9 (50.7-98.0) vs 20.0 (17.7-25.0), p < 0.001; with DEX: 77.9 (56.0-130.5) vs 20.5 (18.6-24.7), p<0.001]. DEX (0.1-5 microM) could also induce apoptosis of lymphocytes from SLE and control subjects in a dose-dependent manner. Elevation of apoptotic susceptibility was more prominent in DEX-treated SLE lymphocytes [33.9% (24.7-37.5%) vs 19.6% (13.6-26.1 %), p = 0.003]. The higher apoptotic susceptibility of SLE lymphocytes upon DEX treatment in vitro may be related, at least partly, to the pharmacological action of corticosteroids.

The topography of intimal thickening and associated remodeling pattern of early transplant coronary disease: influence of pre-existent donor atherosclerosis

BACKGROUND

With native coronary disease, intimal plaque initially accumulates at focal areas in the artery, often accompanied by compensatory vessel enlargement. With transplant coronary disease, the topography of intimal thickening and associated remodeling pattern are less studied.

METHODS

We studied 72 prospectively recruited transplant patients with serial intravascular ultrasound using 4.3F catheters at baseline and at 1-year follow up. We considered 175 ultrasound-recorded segments (mean, 2.4 +/- 1.1 segments per patient) exactly matched on the serial studies by both angiographic criteria and ultrasound criteria, using arterial and venous branch points, pericardium, and sinuses as anatomic landmarks.

RESULTS

Eighty-eight segments had no donor disease, and 87 had donor disease (80 eccentric and 7 concentric intimal thickening). Progressive intimal thickening occurred in 48 segments without (55%) and 43 segments with donor disease (48%, p = NS). Thickening from segments without donor disease was mainly eccentric (81%). Thickening from segments with donor eccentric plaque was also mainly eccentric (67%, p = NS compared with segments without donor disease), with further thickening superimposed on the original plaque. Concentric intimal thickening was uncommon. Of the 58 patients who had >1 segment matched, intimal changes were discordant in 34 (59%), with progression in some and lack of progression in other segments. Total vessel area change correlated with intimal area change (r = 0.37 with a slope of 0.79, p < 0.001), including segments with (r = 0.39; slope, 0.69) and segments without (r = 0.37; slope, 1.16) donor disease.

CONCLUSION

The intimal thickening of early transplant coronary disease is mainly eccentric and often discordant within each individual patient. Donor eccentric plaque often serves as a nidus for further intimal growth. The topography of intimal thickening in transplant coronary disease resembles that of native coronary disease, but the presence of a pre-existent donor plaque may impede compensatory remodeling as further intimal thickening occurs after transplantation.

Logarithmic simulated annealing for X-ray diagnosis

We present a new stochastic learning algorithm and first results of computational experiments on fragments of liver CT images. The algorithm is designed to compute a depth-three threshold circuit, where the first layer is calculated by an extension of the Perceptron algorithm by a special type of simulated annealing. The fragments of CT images are of size 119x119 with eight bit grey levels. From 348 positive (focal liver tumours) and 348 negative examples a number of hypotheses of the type w(1)x(1)+. . .;+w(n)x(n)>/=theta were calculated for n=14161. The threshold functions at levels two and three were determined by computational experiments. The circuit was tested on various sets of 50+50 additional positive and negative examples. For depth-three circuits, we obtained a correct classification of about 97%. The input to the algorithm is derived from the DICOM standard representation of CT images. The simulated annealing procedure employs a logarithmic cooling schedule c(k)=Gamma/ln(k+2), where Gamma is a parameter that depends on the underlying configuration space. In our experiments, the parameter Gamma is chosen according to estimations of the maximum escape depth from local minima of the associated energy landscape.

Elevation of proinflammatory cytokine (IL-18, IL-17, IL-12) and Th2 cytokine (IL-4) concentrations in patients with systemic lupus erythematosus

Previous studies have indicated that the autoimmune phenomenon might be caused by an imbalance of T helper cell (Th) cytokines. We measured the plasma concentrations of three novel proinflammatory cytokines interleukin (IL)-17, IL-18, IL-12 and a key Th2 cytokine IL-4 in patients with systemic lupus erythematosus (SLE) and correlated the ratio of proinflammatory/Th2 cytokines with SLE disease activity index (SLEDAI). Plasma IL-12, IL-17, IL-18 and IL-4 concentrations of 36 SLE patients and 18 sex- and age-matched control subjects were measured by enzyme linked immunosorbent assay. All were significantly higher in SLE patients than control subjects (IL-12, mean+/-s.d. of 166.7+/-84.5 vs 93.5+/-39.2 pg/ml, P<0.001; IL-17, 76.5+/-45.7 vs 37.6+/-35.3 pg/ml, P=0.002; IL-18, 368.7+/-199. 5 vs 141.1+/-47.1 pg/ml, P<0.001; and IL-4, 27.1+/-15.3 vs 17.3+/-7. 2 pg/ml, P<0.05), and IL-18/IL-4 ratio correlated positively and significantly with SLEDAI score (r=0.435, P=0.006). We propose that SLE is characterized by an elevation of both Th1 and Th2 cytokines: the elevation of proinflammatory cytokine IL-12, IL-17 and IL-18 may trigger the inflammatory process in SLE and the elevation of IL-18/IL-4 ratio suggests an imbalance of cytokine profile to mediate the inflammatory response.

A comparison of cytokine responses in respiratory syncytial virus and influenza A infections in infants

Respiratory syncytial virus (RSV) infection is a major cause of bronchiolitis in infants while influenza A infection usually manifests as upper respiratory tract infection. We hypothesised that the immunological responses of infants to RSV infection and influenza A infection are different. This prospective study was undertaken to compare the cytokine responses during RSV and influenza A infection. Sera and nasopharyngeal aspirates (NPA) were collected from infants with a coryzal illness with or without wheeze who were admitted to the paediatric wards during 1998. Cytokines, adhesion molecules, RANTES, IgE and eosinophil cationic protein (ECP) were measured by enzyme linked immunosorbent assay or fluorescence enzyme immunoassay. The diagnosis of RSV and influenza infections was based on direct immunofluorescence and viral culture. Of the 39 infants studied, RSV infection was confirmed in 11 patients and Influenza A in 10 patients. All RSV patients and one influenza A patient had wheeze during the infection. The serum concentrations of interleukin (IL)-4 and IL-5, regulated upon activation normal T cell expressed and secreted (RANTES) and soluble intercellular adhesion molecule 1 (sICAM-1) in infants with RSV infection were significantly higher than those with influenza A infection (all P < 0.02). The concentration of tumour necrosis factor-alpha (TNF-alpha) in NPA was significantly lower in infants with RSV infection (P < 0.01).

CONCLUSION

A predominant T helper cell type 2 cytokine and related immunological response was observed in infants with respiratory syncytial virus infection whereas a predominant pro-inflammatory cytokine response was observed in infants with influenza A infection. This may explain the different clinical manifestations of the two viral infections in infants.

Effects of cortisol on chloride cells in the gill epithelium of Japanese eel, Anguilla japonica

The purpose of the present study was to determine the effects of cortisol on the development of the freshwater chloride cell (CC), using flow cytometry. Scanning electron microscopy was used to determine the corresponding modifications in CC apical structure. Simultaneously, biochemical analyses were conducted to determine the activities of transport ATPases, mitochondrial enzymes (succinate dehydrogenase (SDH) and Mg(2+)-ATPase) and lactate dehydrogenase (Ldh). The effects of daily i.m. injection of 2 microg/g cortisol were compared with sham-injected freshwater-, control freshwater- and seawater-adapted fish. The hormone did not affect the activities of Ca(2+)-ATPases in CCs. However, it stimulated the proliferation and differentiation of the two freshwater CC subtypes (F1, 66+/-2.18% (s.e.m. ) and F2, 34+/-2.18%), in which the relative proportion of F1 CCs was transiently reduced in the first 5 days of treatment (F1, 53+/-1.83%; F2, 47+/-1.83%) but was then restored to a higher relative percentage on day 10 (F1, 70+/-1.42%; F2, 30+/-1.42%). Biochemically, it induced the activities of Na(+)/K(+)-ATPase, Mg(2+)-ATPase, SDH and Ldh, suggesting an increase in ion pumping and its associated metabolic activities. CCs from cortisoltreated fish demonstrated recessed apical morphology, accompanied by an increase in cell density (2012 to 2413/mm(2)). Nevertheless, the extent of cell proliferation and differentiation and the biochemical changes were significantly lower than those of seawater fish. Our results indicate that cortisol alone cannot stimulate a complete differentiation of freshwater CCs to seawater CCs. However, the respective roles of the two CC subtypes in freshwater and seawater environments are indicated.

Heavy metal concentrations in marine fishes collected from fish culture sites in Hong Kong

The levels of six heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) in different tissues of three species of cultured marine fishes (Epinephelus areolatus, Lutjanus russelli, and Sparus sarba) collected from three fish culture sites in Hong Kong were evaluated. Metal pollution problems in the fish culture sites were serious, as reflected by the high metal concentrations recorded in sea water, sediments, and the biomonitor Perna viridis. In general, tissues of all three species contained high concentrations of Zn and Cu, but much lower concentrations of Ni, Pb, Cd, and Cr. Similar pattern of heavy metal concentrations was observed in sea water, sediment, and P. viridis. Metal concentrations in various tissues varied greatly among species and among fish culture sites. Different tissues showed different capacity for accumulating heavy metals. Gonad of all three species contained high concentrations of Zn. On the other hand, liver seemed to be the primary organ for Cu accumulation. Overall, metal concentrations in the tissues of culture marine fishes were much lower than those in P. viridis. Despite high metal levels in sea water and sediments, concentrations of Cd, Cr, and Pb in edible tissues, including muscle and skin, did not exceed permissible levels recommended by the Hong Kong Government for human consumption.

Anosacral cutaneous amyloidosis: a study of 10 Chinese cases

BACKGROUND

Primary cutaneous amyloidoses are rare in Western countries, but are relatively common in Taiwan. Anosacral cutaneous amyloidosis is a rare type of primary cutaneous amyloidoses, first reported in Japanese patients.

PATIENTS/METHODS

In the present study, we investigated the age of onset, sites of involvement, associated systemic diseases, and histopathological findings in 10 cases of anosacral cutaneous amyloidosis seen during the past 27 years.

RESULTS

In previous reports the aetiology of anosacral cutaneous amyloidosis was thought to be a senile change, but half of our patients developed the disease before the age of 60 years. Based on our histopathological findings, apoptosis may be the initial event causing amyloid deposition, although the precise mechanism causing apoptosis needs further investigation. Three patients were found to have diabetes mellitus, but any relationship to anosacral cutaneous amyloidosis is unclear.

CONCLUSIONS

No cases of this cutaneous disorder have been reported in the Western literature; there seems to be a racial difference accounting for the disease, although the precise factor is not clarified yet. The disease could easily be misdiagnosed as lichen simplex chronicus, postinflammatory hyperpigmentation or tinea cruris; therefore, a thorough history, a careful physical examination and a skin biopsy is needed to establish a firm diagnosis.

New atrial fibrillation after acute myocardial infarction independently predicts death: the GUSTO-III experience

BACKGROUND

Atrial fibrillation (AF) or flutter occurring after myocardial infarction may occur alone or in association with other complications. Whether the arrhythmia portends a poor prognosis independent of other complications with contemporary therapy is unknown.

METHODS AND RESULTS

As part of the Global Use of Strategies To Open occluded coronary arteries (GUSTO-III) trial, we evaluated whether postinfarction complications were associated with the subsequent development of AF and whether AF independently predicted death over periods of 30 days and 1 year. Information including exact timing was collected on deaths and major in-hospital postinfarction complications up to 30 days. Of the 13,858 patients with sinus rhythm at enrollment, 906 later had AF or flutter and 12, 952 did not. We compared outcomes between these 2 groups, adjusting for differences in baseline characteristics and prefibrillation complications. Worsening heart failure, hypotension, third-degree heart block, and ventricular fibrillation were independent predictors of new-onset AF. The unadjusted odds ratio (OR) for death among patients with versus those without AF was 2.74 (95% confidence interval [95% CI], 2.56-3.34). After adjusting for baseline differences, the OR was reduced to 1.63 (95% CI, 1.31-2.02). Adjustment for other in-hospital complications before the onset of AF further reduced the OR to 1.49 (95% CI, 1.17-1.89).

CONCLUSIONS

Atrial fibrillation or flutter occurs secondary to other postinfarction complications but independently portends a worse prognosis. Prevention and management may improve outcome.

Changes in endogenous Zn and Cu distribution in different cytosolic protein fractions in mouse liver after administration of a single sublethal dose of CdCl(2)

The time course of change in tissue Cd, Cu and Zn contents, their distribution in cellular protein fractions as well as the profile of MT gene expression in mouse liver was described over a 7 days period following a single intraperitoneal injection of 2 mg/kg of CdCl(2). The result showed that Cd accumulated rapidly in mouse liver. Between 1 h and 7 days after administration, over 18% of the total Cd administered were found in the liver. Cd administration was also associated with the overexpression of the MT-mRNA. However, the time course of induction was not parallel to the change in tissue Cd content. When separated on a Sephadex G-75 column, majority of Cd was found to bind to the fractions known to contain the metal-binding protein, metallothionein (MT). From day 2 after Cd administration, a small amount of the metal was also found associated with the high molecular weight (HMW) proteins. In addition to Cd, tissue Zn content was affected most during the entire study. There was a significant decrease in tissue Zn content during the initial 8 h but tissue Zn content increased significantly throughout the following 6 days. At 1-7 days, majority of Zn was associated with the HMW protein fraction. Although there was no significant change in total tissue Cu content, distribution of Cu in different protein fractions was detected. While in control animals, Cu was mainly associated with the HMW proteins, some was found in the MT fraction on the second day. On the 7th day, Cu distribution had deteriorated. Together with changes seen in Cd, the results might suggest that injury had occurred in the tissue at this time. The results of the present study showed that Cd caused a change in subcellular distribution of tissue endogenous metals, which might reflect alteration of cellular functional activities.

Medical treatment for acute coronary syndromes

The medical treatment of acute coronary syndromes with thrombolytic, antithrombin, and antiplatelet agents is a major area of research and a vast topic for clinical review. This review summarizes important recent findings on the background of existing pathological and clinical knowledge to provide an understanding of the basis of current therapy and the new therapies that are likely to be introduced in the near future. Current controversies regarding the management of these conditions and the choice between medical, interventional, and combined strategies in different situations are also discussed.

Role of caspases in dexamethasone-induced apoptosis and activation of c-Jun NH2-terminal kinase and p38 mitogen-activated protein kinase in human eosinophils

Eosinophils are the principal effector cells for the pathogenesis of allergic inflammation. Glucocorticoids such as dexamethasone have long been used therapeutically for eosinophilia in allergic inflammation by inducing eosinophil apoptosis, but little is known about the intracellular mechanisms mediating dexamethasone-induced apoptosis. In the present study, we investigated the effect of dexamethasone on three mitogen-activated protein kinases (MAPK) involved in the intracellular signalling pathway: c-Jun NH2-terminal kinase (JNK), p38 MAPK and extracellular signal-regulated kinase (ERK). We found that dexamethasone could activate JNK and p38 MAPK in a time-dependent manner but not ERK. Further, SB 203580, a specific p38 MAPK inhibitor, was additive with dexamethasone in inducing eosinophil apoptosis, while JNK1/2 antisense phosphorothioate oligodeoxynucleotides did not show any significant effect. These suggest that dexamethasone-induced JNK1/2 and p38 MAPK activation are not crucial to the induction of apoptosis. Pretreatment of eosinophils with benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD.FMK), a broad-spectrum caspase inhibitor, could inhibit dexamethasone-induced apoptosis in eosinophils dose-dependently. Moreover, Z-VAD.FMK partially inhibited dexamethasone-activated JNK and p38 MAPK activities. However, dexamethasone treatment did not activate specific caspase-3, -8 activity in eosinophils compared with spontaneous apoptosis. We therefore conclude that dexamethasone-induced apoptosis and activation of JNK and p38 MAPK activity in eosinophils are regulated by caspases but not through the common apoptosis-related caspase-3, -8 as in other cell types. Elucidation of the important role of caspases in eosinophil apoptosis may facilitate the development of more specific and effective treatment for allergic inflammation.

Elevation of plasma interleukin-18 concentration is correlated with disease activity in systemic lupus erythematosus

BACKGROUND

Previous studies have indicated that the autoimmune phenomenon might be caused by an imbalance of T-helper cell (Th) cytokines.

METHODS

We investigated the plasma concentrations of a novel pro-inflammatory Th1 cytokine, interleukin (IL)-18, and its inducer, IL-12, in patients with systemic lupus erythematosus (SLE) and correlated them with the SLE disease activity index (SLEDAI). Plasma IL-18 and IL-12 concentrations of 40 SLE patients and 18 sex- and age-matched control subjects were measured by enzyme-linked immunosorbent assay.

RESULTS

Plasma IL-18 and IL-12 concentrations were significantly higher in SLE patients than in control subjects [median (interquartile range): IL-18, 320.0 pg/ml (164.4-475.6 pg/ml) vs 130.1 pg/ml (57.8-202.4 pg/ml), P<0.001; IL-12, 143.3 pg/ml (39.4-247.2 pg/ml) vs. 84.7 pg/ml (29.3-140.1 pg/ml), P<0.001]. Increases in IL-18 concentration correlated positively and significantly with SLEDAI score (r = 0.449, P = 0.004).

CONCLUSION

The novel cytokine IL-18 might play a crucial role in triggering the inflammatory processes in SLE.

Differential diagnosis of Hb EE and Hb E-beta(0)-thalassemia by protein and DNA analyses

DNA analysis was used to confirm the Hb EE genotype and to differentiate from the possible genotype of Hb E-beta(0)-thalassemia in two Malay patients. The first patient was a 13-year-old Malay girl, whose parents were available for family studies. The second patient was a 69-year-old Malay woman with no living family members. The presence of Hb E in both propositi was confirmed by: (1) its characteristic electrophoretic mobilities on alkaline/acid gels; (2) its chromatographic properties on anion/cation exchangers, and (3) its mildly insoluble properties. However, differential diagnosis of Hb EE and Hb E-beta(0)-thalassemia was challenging in these two cases. In the former, this was because of the possible interactions of the parents' phenotypes; i.e., the mother had a similar phenotype. In the latter, it was due to the lack of any living family members for family studies. In this communication, we present the protein and DNA analyses, including data on the use of the restriction enzyme Mnl I, for the definitive diagnosis of the Hb EE genotype in the propositi of these two Malay families.

Unna and elastic postoperative dressings: comparison of their effects on function of adults with amputation and vascular disease

OBJECTIVES

To compare the functional outcome associated with the use of Unna semirigid dressings (SRD) and elastic bandage soft dressings (ED) for adults with lower limb amputation.

DESIGN

Experimental design.

SETTING

Inpatient rehabilitation unit of an urban academic medical center.

PARTICIPANTS

A successive series of adults with vascular disease who had lower limb amputation surgery. Subjects were randomly assigned to the SRD (12 patients with 12 recent amputations) or the ED (9 patients with 10 recent amputations) group. Subjects in each group were not significantly different except for age; those in the SRD group were somewhat older.

INTERVENTION

Subjects in the SRD group had Unna dressings applied to the amputation limb by physical therapists trained in the technique. Those in the ED group had elastic bandaging by therapists, nurses, family, and themselves, all of whom were trained in the technique.

RESULTS

Sixty-seven percent of the SRD group and 20% of those in the ED group were discharged from the rehabilitation unit ambulating with prostheses. Of those who received prostheses, time from admission to the rehabilitation unit to readiness for fitting averaged 20.8 days for the SRD group and 28.7 days for the ED group. Comparison of survival curves shows that the time from surgery to fitting in the SRD group was almost half that of the ED group; 30% of the SRD group was fitted within 34 days, whereas it took 64 days for the same percentage of the ED group to be fitted.

CONCLUSIONS

Unna semirigid dressings are more effective in fostering amputation limb wound healing and preparing the amputation limb for prosthetic fitting. Subjects treated with SRDs were more likely to be fitted with prostheses and to return home walking with a prosthesis.

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.