Effect of simulated commercial flight on oxygenation in patients with interstitial lung disease and chronic obstructive pulmonary disease

BACKGROUND

Commercial aircraft cabins provide a hostile environment for patients with underlying respiratory disease. Although there are algorithms and guidelines for predicting in-flight hypoxaemia, these relate to chronic obstructive pulmonary disease (COPD) and data for interstitial lung disease (ILD) are lacking. The purpose of this study was to evaluate the effect of simulated cabin altitude on subjects with ILD at rest and during a limited walking task.

METHODS

Fifteen subjects with ILD and 10 subjects with COPD were recruited. All subjects had resting arterial oxygen pressure (PaO2) of >9.3 kPa. Subjects breathed a hypoxic gas mixture containing 15% oxygen with balance nitrogen for 20 minutes at rest followed by a 50 metre walking task. Pulse oximetry (SpO2) was monitored continuously with testing terminated if levels fell below 80%. Arterial blood gas tensions were taken on room air at rest and after the resting and exercise phases of breathing the gas mixture.

RESULTS

In both groups there was a statistically significant decrease in arterial oxygen saturation (SaO2) and PaO2 from room air to 15% oxygen at rest and from 15% oxygen at rest to the completion of the walking task. The ILD group differed significantly from the COPD group in resting 15% oxygen SaO2, PaO2, and room air pH. Means for both groups fell below recommended levels at both resting and when walking on 15% oxygen.

CONCLUSION

Even in the presence of acceptable arterial blood gas tensions at sea level, subjects with both ILD and COPD fall below recommended levels of oxygenation when cabin altitude is simulated. This is exacerbated by minimal exercise. Resting sea level arterial blood gas tensions are similarly poor in both COPD and ILD for predicting the response to simulated cabin altitude.

The effect of celecoxib on intrathecal morphine-induced pruritus in patients undergoing Caesarean section

Pruritus associated with intrathecal opioid administration is particularly common in pregnancy. Nonsteroidal anti-inflammatory drugs (NSAIDs) can reduce the severity of this pruritus but have undesirable side effects. The recent development of drugs that can specifically inhibit the cyclooxygenase 2 isoenzyme have become an attractive alternative. This study was designed to evaluate the efficacy of such a drug (celecoxib) in reducing intrathecal opioid-induced pruritus in a randomised double-blinded study of 60 women undergoing Caesarean section. All of them received spinal anaesthesia with 3 ml of 0.5% hyperbaric bupivacaine and 0.3 mg preservative-free morphine. After delivery of the baby, they received either oral celecoxib 200 mg or placebo. Visual analogue scores for pain and pruritus were measured at 30 min, 2, 4, 8, and 24 h. There was no difference in the severity and onset of pain and pruritus between the two groups. Timing of administration, inadequate dosing and possible altered pharmacokinetics in pregnancy may explain the lack of efficacy.

Plasma inflammatory cytokines and chemokines in severe acute respiratory syndrome

Severe acute respiratory syndrome (SARS) is a recently emerged infectious disease caused by a novel coronavirus, but its immunopathological mechanisms have not yet been fully elucidated. We investigated changes in plasma T helper (Th) cell cytokines, inflammatory cytokines and chemokines in 20 patients diagnosed with SARS. Cytokine profile of SARS patients showed marked elevation of Th1 cytokine interferon (IFN)-gamma, inflammatory cytokines interleukin (IL)-1, IL-6 and IL-12 for at least 2 weeks after disease onset, but there was no significant elevation of inflammatory cytokine tumour necrosis factor (TNF)-alpha, anti-inflammatory cytokine IL-10, Th1 cytokine IL-2 and Th2 cytokine IL-4. The chemokine profile demonstrated significant elevation of neutrophil chemokine IL-8, monocyte chemoattractant protein-1 (MCP-1), and Th1 chemokine IFN-gamma-inducible protein-10 (IP-10). Corticosteroid reduced significantly IL-8, MCP-1 and IP-10 concentrations from 5 to 8 days after treatment (all P < 0.001). Together, the elevation of Th1 cytokine IFN-gamma, inflammatory cytokines IL-1, IL-6 and IL-12 and chemokines IL-8, MCP-1 and IP-10 confirmed the activation of Th1 cell-mediated immunity and hyperinnate inflammatory response in SARS through the accumulation of monocytes/macrophages and neutrophils.

Consensus statement on ischaemic stroke care in Hong Kong

OBJECTIVE

To issue guidelines for the care of acute stroke in Hong Kong, with the target audience of all health care professionals who are involved in acute stroke care.

PARTICIPANTS

The Hong Kong Neurological Society and the Hong Kong Stroke Society.

EVIDENCE

The panel applied the 'rule of evidence' used by the United States Agency for Health Care Policy and Research. When there is insufficient evidence, the recommendation was based on customary practice and was circulated among the members and fellows of the two societies before coming to a consensus.

CONSENSUS PROCESS

Group meetings were held in 2002 to review the literature about acute care for patients with ischaemic stroke and to issue a consensus statement with reference to the local health care system. Participants of the meetings were appointed by the councils of The Hong Kong Neurological Society and the Hong Kong Stroke Society. The draft statement was circulated among the members and fellows of the two societies for comments before it was finalized.

CONCLUSIONS

Ischaemic stroke is a heavy health care burden to Hong Kong. The current consensus statement provides a framework to establish a multidisciplinary approach towards its acute management.

Serum LD1 isoenzyme and blood lymphocyte subsets as prognostic indicators for severe acute respiratory syndrome

BACKGROUND

The pathophysiology of severe acute respiratory syndrome (SARS) is at present poorly understood, but advanced age and serum total lactate dehydrogenase (LD) activity >300 U L(-1) have been associated with adverse clinical outcomes. Blood leucocytes and lymphocyte subsets were reported to decrease, respectively, in 47% and up to 100% of 38 patients in Beijing. However, their prognostic implications have not been thoroughly investigated.

OBJECTIVE

To investigate serum total LD, LD isoenzymes, and other parameters including blood lymphocyte subsets as prognostic indicators in SARS patients for adverse clinical outcomes in terms of admission to intensive care unit (ICU) and death.

DESIGN

Retrospective analysis.

SUBJECTS AND METHODS

A total of 109 patients with a clinical diagnosis of SARS according to the modified World Health Organization case definition of SARS were recruited from two major acute hospitals in Hong Kong. They were either involved in the initial outbreak of SARS, or cases from the community outbreak of Amoy Gardens between 10 March and 5 May 2003. The clinical diagnosis was subsequently confirmed by serological test and/or molecular analysis. Serum total LD and LD isoenzyme activities, complete blood picture with total leucocyte count and differential counts, absolute counts of CD3+, CD4+, CD8+, natural killer cells and B lymphocytes were measured daily upon admission. Receiver operating characteristic curve analysis was used to determine and compare different cut-offs for various biochemical and immunological parameters at peak serum total LD concentration in predicting adverse clinical outcomes.

RESULTS

Of a total of 109 patients, 41 were admitted to ICU and 42 died. Of 42 fatal patients, 24 died in ICU and 18 died in general medical wards. Age was found to be an independent prognostic indicator for death with an area under curve (AUC) of 0.96 [95% confidence interval (CI) = 0.90-0.99] but not for admission to ICU [AUC = 0.61 (CI = 0.51-0.70)]. Whilst serum total LD could only achieve AUC of 0.68 (CI = 0.59-0.77) for predicting death, LD1 isoenzyme was found to be the best biochemical prognostic indicator with AUC of 0.84 (CI = 0.75-0.90), sensitivity of 62% (CI = 46-76%), specificity of 93% (CI = 83-98%) at cut-off activity of > or =80 U L(-1). CD3+, CD4+, CD8+ and natural killer cell counts were promising immunological prognostic indicators for predicting admission to ICU with AUC of 0.94 (CI = 0.86-0.98), 0.91 (CI = 0.81-0.96), 0.93 (CI = 0.85-0.98), and 0.87 (CI = 0.76-0.94), respectively.

CONCLUSIONS

Apart from age, serum LD1 activity was the best prognostic indicator for predicting death in patients with SARS compared with serum total LD activity, haemoglobin concentration, leucocyte and lymphocyte counts. Its release could possibly be from blood erythrocytes and body tissues other than the myocardium. Blood CD3+, CD4+, CD8+ and natural killer cell counts were found to be good prognostic indicators for predicting admission to ICU in patients with SARS compared with age, leucocyte count and LD isoenzymes. The suppressed CD3+, CD4+, CD8+, and natural killer cell counts were also implicated in the pathophysiology of SARS. Patients with increased serum LD1 should be closely monitored to ensure prompt management, and preparation for admission to ICU could be planned ahead for patients with suppressed lymphocyte subsets.

Management of extremity soft tissue sarcoma after unplanned incomplete resection: experience of a regional musculoskeletal tumour centre

This study reviews the presentation and management of extremity soft tissue sarcoma after unplanned incomplete resection in a musculoskeletal tumour centre in Hong Kong. Medical records of 18 patients who were referred to our centre for further management from January 1995 to May 2001 after inadequate tumour excision were reviewed. Fourteen patients had been referred from private clinics and four from public hospitals. At initial presentation, 10 patients had lesions exceeding 5 cm, nine had a tumour deep in the subfascial plane, and eight had tumours that had recently increased in size. Sixteen had no preoperative radiological assessment or biopsy performed before excision. All except two patients needed additional skin and muscle reconstruction in a subsequent re-resection, and 12 required postoperative radiotherapy. Two patients subsequently developed distant metastases, and one patient died of an unrelated cause. No amputations were required, and no major complications arose from second surgery. Physicians' alertness towards the possible malignancy of soft tissue masses in extremities is important to avoid a potentially mutilating second resection. Well-planned re-resection in a specialised tumour centre can achieve satisfactory local control of disease.

Immunomodulatory effects of Yun Zhi and Danshen capsules in health subjects—a randomized, double-blind, placebo-controlled, crossover study

Immunostimulating polysaccharides extracted from the Chinese medicinal plant Yun Zhi (Coriolus versicolor) have been found to enhance various immunological functions, and Danshen (Salvia miltiorrhiza) to show beneficial effects on the circulatory system. In the present clinical study, we investigated if regular consumption of Yun Zhi and Danshen capsules could improve cellular immunity in healthy subjects. One hundred healthy subjects were recruited to take Yun Zhi (50 mg/kg body weight) plus Danshen (20 mg/kg body weight) or placebo capsules daily for four successive months and, after a 2-month wash-out period, crossover to take placebo or Yun Zhi plus Danshen capsules for four successive months. Flow cytometry was used to assess the lymphocyte subtypes and concentration of T helper (Th) cell cytokines in culture supernatant. Gene expression of cytokines and cytokine receptors of peripheral blood mononuclear cells (PBMC) was analyzed by cDNA expression array. Results showed that regular oral consumption of Yun Zhi-Danshen capsules could significantly elevate PBMC gene expression of interleukin (IL)-2 receptor, increase the percentage and absolute counts of T helper cell and ratio of CD4(+) (T helper)/CD8(+) (T suppressor and cytotoxic T) cell, and significantly enhance the ex vivo production of typical Th1 cytokine interferon-gamma from PBMC activated by phytohemagglutinin and lipopolysaccharide (all p<0.005). Such consumption had no adverse effects on liver and renal functions, and the biochemical bone profile. Therefore, regular consumption of Yun Zhi and Danshen could be beneficial for immunological functions by potential enhancement of cell-mediated immunity in healthy subjects without any adverse effects.

Outcome analysis of intraventricular thrombolytic therapy for intraventricular haemorrhage

OBJECTIVES

To evaluate the outcome of intraventricular thrombolytic therapy for intraventricular haemorrhage and to formulate a safe and effective regimen.

DESIGN

Retrospective study.

SETTING

Regional neurosurgical centre, Hong Kong.

PATIENTS

Twenty-nine consecutive adult patients who presented from November 1995 to November 1998 with non-traumatic intraventricular haemorrhage (Graeb score, > or =7) with no active rebleeding risks from vascular abnormalities.

INTERVENTIONS

Fourteen consecutive patients received intraventricular streptokinase via the external ventricular drainage, and 15 consecutive patients received intraventricular urokinase treatment.

MAIN OUTCOME MEASURES

Patient demographics, Glasgow coma scale score, Graeb score, mortality rate, shunt rate, fever response, infection rate, catheter blockage rate, and local and systemic bleeding tendency.

RESULT

The mean age of the 16 men and 13 women was 59 years (range, 14-76 years). The median Graeb score for cases of intraventricular haemorrhage was 10 (range, 7-12). There was no significant difference in terms of the Graeb score distribution, total dosage, and duration of treatment between the streptokinase and urokinase groups. More cases of fever were observed in the streptokinase group, which could be due to its antigenicity. The infection rate of the central nervous system was 3%, and the shunt rate was 24%. The overall 1-month postoperative mortality was 10%, which was related to a low preoperative Glasgow coma scale score (< or =4). No local rebleeding, systemic coagulopathy, or catheter blockage occurred.

CONCLUSIONS

Intraventricular thrombolytic therapy is a safe and effective method of managing intraventricular haemorrhage. We suggest instilling 20 000 units urokinase intra-operatively, followed by 20 000 units daily for about 3 days, except in cases of vascular abnormality, bleeding tendency, and trauma.

Application of a toxicity identification evaluation for a sample of effluent discharged from a dyeing factory in Hong Kong

A first toxicity identification evaluation (TIE) was conducted in three phases using the Microtox test to identify the major toxicant(s) in effluent discharged from a dyeing plant in Hong Kong. In Phase I toxicity characterization indicated that anions were likely to be the major toxicants for the entire effluent. In Phase II concentrations of sulfite and other anions in the original and the anion exchange resin-treated effluent samples were determined by ion chromatography. Anions, which were found in the effluent at comparatively high concentrations and were suspected of being responsible for the toxicity to luminescent bacteria, were selected for further study in Phase III. Investigation in Phase III using the spiking and mass balance approaches confirmed that the sulfite ion was the major toxicant in the effluent.

Suppressive effect of combination treatment of leflunomide and methotrexate on chemokine expression in patients with rheumatoid arthritis

To study the immunosuppressive and anti-inflammatory effects of combined leflunomide and methotrexate (MTX) therapy on chemokine expression in patients with rheumatoid arthritis (RA), nine patients were enrolled for the combination therapy for 24 weeks. These patients have been on treatment with MTX 15 mg/week for not less than 3 months before entry to the study. A loading dose of l00 mg/day of leflunomide was given for 3 days, followed by 10 mg/day for the rest of the study period. Plasma concentrations of monocyte chemotactic protein-1 (MCP-1), thymus- and activation-regulated chemokine (TARC), and macrophage-derived chemokine (MDC) were assayed before and after combination treatment by ELISA. Gene expression of inflammatory cytokines and chemokines of peripheral blood mononuclear cells was analysed by cDNA expression array. Plasma MCP-1, TARC and MDC concentrations were significantly lower in patients after combination treatment [median (interquartile range) before versus after treatment: MCP-1 of 118.0 (64.0-515.2) versus 3.2 (0.0-22.8) pg/ml, P < 0.01; TARC of 126.1 (27.2-197.4) versus 0.0 (0.0-52.5) pg/ml, P < 0.05; MDC of 503.3 (446.2-600.9) versus 366.8 (337.4-393.4) pg/ml, P < 0.05]. Positive correlations among reductions in plasma chemokines and clinical outcome measures were also found. Expression of chemokine genes including MDC and TARC was suppressed after combination treatment [% suppression of 38.7 (54.3-13.0) and 53.7 (55.9-28.4), respectively]. Combination therapy with leflunomide and MTX exhibits anti-inflammatory activity in the suppression of chemokine expression and subsequent recruitment of inflammatory cells into the inflammatory sites in RA.

Haematological manifestations in patients with severe acute respiratory syndrome: retrospective analysis

OBJECTIVES

To evaluate the haematological findings of patients with severe acute respiratory syndrome (SARS).

DESIGN

Analysis of the demographic, clinical, and laboratory characteristics of patients with SARS.

SETTING

Prince of Wales Hospital, Hong Kong. Subjects All patients with a diagnosis of SARS between 11 March and 29 March 2003 who had no pre-existing haematological disorders.

MAIN OUTCOME MEASURES

Clinical end points included the need for intensive care and death. Univariate and multivariate analyses were performed to examine factors associated with adverse outcome.

RESULTS

64 male and 93 female patients were included in this study. The most common findings included lymphopenia in 153 (98%) of the 157 patients, neutrophilia in 129 (82%), thrombocytopenia in 87 patients (55%), followed by thrombocytosis in 77 (49%), and isolated prolonged activated partial thromboplastin time in 96 patients (63%). The haemoglobin count dropped by more than 20 g/l from baseline in 95 (61%) patients. Four patients (2.5%) developed disseminated intravascular coagulation. Lymphopenia was shown in haemato-lymphoid organs at postmortem examination. Multivariate analysis showed that advanced age and a high concentration of lactate dehydrogenase at presentation were independent predictors of an adverse outcome. Subsets of peripheral blood lymphocytes were analysed in 31 patients. The counts of CD4 positive and CD8 positive T cells fell early in the course of illness. Low counts of CD4 and CD8 cells at presentation were associated with adverse outcomes.

CONCLUSIONS

Abnormal haematological variables were common among patients with SARS. Lymphopenia and the depletion of T lymphocyte subsets may be associated with disease activity.

Plasma TARC concentration may be a useful marker for asthmatic exacerbation in children

Recent studies suggested the T-helper cells type-2 lymphocytes-specific thymus and activation-regulated chemokine (TARC) and monocyte-derived chemokine (MDC) are useful inflammatory markers for chronic asthma. However, their roles in assessing the severity of acute asthma are unknown. This study aims to evaluate the serial changes of plasma TARC and MDC concentrations in children with asthmatic exacerbation. All patients with acute asthma were treated with systemic corticosteroid for 5 days. The severity of asthmatic exacerbation was classified according to the Global Initiative for Asthma guidelines. Plasma TARC and MDC concentrations were measured by sandwich enzyme immunoassays. Sixteen children, with a median (interquartile range) age of 9.3 (7.2-10.6) yrs and asthmatic exacerbation, were recruited. Plasma TARC concentration showed inverse correlation with peak expiratory flow rate at presentation. The median plasma TARC concentration was highest during the acute attacks (46 pg x mL(-1)) as compared to those levels at 1 (31 pg x mL(-1)) and 5 weeks (32 pg x mL(-1)) following treatment. The median plasma MDC level similarly decreased from 698 pg x mL(-1) at baseline to 261 pg x mL(-1) 1 week later, but increased back to 574 pg x mL(-1) at 5 weeks. These results suggest that plasma T-helper cells type-2 lymphocytes-specific thymus and activation-regulated chemokine but not monocyte-derived chemokine concentration may be a useful inflammatory marker in assessing asthmatic exacerbation in children.

A study of candidate genes for psoriasis near HLA-C in Chinese patients with psoriasis

BACKGROUND

Genetic analyses have identified the HLA-Cw6 allele as the major risk allele for psoriasis in many racial groups. However, by serological typing, HLA-Cw6 is not considered a risk factor in Chinese psoriatics. There are several susceptibility genes for psoriasis residing in chromosome 6p near the HLA-C locus, including the corneodesmosin (CDSN) gene, the octamer transcription factor-3 (POU5F1) gene, the major histocompatibility complex class I chain-related gene A (MICA), and the gene for tumour necrosis factor (TNF)-alpha. However, the information about their role in psoriasis in Chinese patients is limited.

OBJECTIVES

We aimed to determine whether Cw6 and the genetic polymorphism of the CDSN gene, POU5F1 gene, MICA gene and the gene for TNF-alpha promoter region were associated with an increased risk of psoriasis in Chinese patients.

METHODS

We conducted a case-control association study in 105 Chinese patients with psoriasis vulgaris and 160 control subjects of similar ages. Genotypes of Cw6, the CDSN gene, the POU5F1 gene, and the gene for the TNF-alpha promoter region were determined by polymerase chain reaction (PCR) followed by restriction enzyme digestion. Genotyping of MICA was determined by PCR combined with fluorescent-based automated fragment detection technology. Results The allele frequencies showed no differences between patients and controls for the POU5F1 gene, MICA gene and the gene for TNF-alpha promoter region. The frequency of the HLA-Cw6 allele in the psoriasis group was significantly higher than that in the control group (18.6% vs. 6.56%, P < 0.00005). For the CDSN gene, patients were more likely to have C allele at position +619 (P = 0.006) and C allele at position +1243 (P = 0.007), but the significance disappeared after correction for multiple testing (Pc > 0.05).

CONCLUSIONS

HLA-Cw6 remains the most significant susceptibility gene in Chinese patients with psoriasis. However, the role of the CDSN gene in the pathogenesis of psoriasis deserves further scrutiny.

Tumour necrosis factor-alpha-induced expression of intercellular adhesion molecule-1 on human eosinophilic leukaemia EoL-1 cells is mediated by the activation of nuclear factor-kappaB pathway

BACKGROUND

Intercellular adhesion molecule-1 (ICAM-1) has been shown to mediate the adhesion and migration of eosinophils to the site of allergic inflammation. However, molecular mechanisms regulating the expression of ICAM-1 in eosinophils are still being elucidated. We investigated the effect of tumour necrosis factor-alpha (TNF-alpha) on ICAM-1 expression of eosinophils.

METHODS

The surface expression of ICAM-1 on a human eosinophilic leukaemic cell line, EoL-1, was assessed by immunocytochemical staining. The phosphorylation of inhibitor kappa B-alpha (IkappaB-alpha) and p38 mitogen-activated protein kinase (MAPK) was detected by Western blot. Nuclear factor kappa-B (NF-kappaB) pathway-related genes were evaluated by the cDNA expression array system, whereas the activity of NF-kappaB was measured by electrophoretic mobility shift assay (EMSA).

RESULTS

TNF-alpha was found to induce the cell surface expression of ICAM-1. A specific proteasome inhibitor N-cbz-Leu-Leu-leucinal (MG-132), but not a p38 MAPK inhibitor (SB 203580), was found to suppress the TNF-alpha-induced expression of ICAM-1 on EoL-1 cells. The gene expressions of ICAM-1, NF-kappaB and IkappaBalpha were up-regulated after the stimulation with TNF-alpha. Further, TNF-alpha was shown to induce IkappaB-alpha phosphorylation and degradation, thereby indicating the activation of NF-kappaB. In EMSA, there was a shifted NF-kappaB band on TNF-alpha-treated cells with or without SB 203580, but no shifted band was observed on MG-132-treated cells.

CONCLUSION

In vitro studies of EoL-1 cells, an eosinophilic leukaemic cell line, confirmed that NF-kappaB plays an important role in the expression of ICAM-1 and recruitment of eosinophils in allergic inflammation.

Tuberculous meningitis with spinal tuberculous arachnoiditis

This report is of a 36-year-old woman who initially presented with confusion and fever. Subsequent investigations showed tuberculous meningitis with acute hydrocephalus. Ventriculoperitoneal shunt was performed and anti-tuberculosis therapy was given. The patient was later noticed to have weakness of both lower limbs and urinary retention. Magnetic resonance imaging of the thoracic spine showed radiological features of tuberculous arachnoiditis with cord compression. Decompressive laminectomy was performed and high-dose systemic corticosteroid was given. A high level of awareness is required when diagnosing tuberculous arachnoiditis and the importance of high-dose corticosteroid in the treatment regimen is emphasised.

Elevated plasma concentrations of nitric oxide, soluble thrombomodulin and soluble vascular cell adhesion molecule-1 in patients with systemic lupus erythematosus

OBJECTIVE

To investigate the correlations among plasma concentrations of nitric oxide (NO), soluble thrombomodulin (sTM) and vascular cell adhesion molecule (sVCAM-1), and whether these three molecules are associated with renal involvement in patients with systemic lupus erythematosus (SLE).

METHODS

Plasma NO concentrations of 73 SLE patients (35 with renal disease, RSLE patients; 38 without renal disease, SLE patients) and 28 age- and sex-matched healthy control subjects were measured by the non-enzymatic Griess assay, and sTM and sVCAM-1 by enzyme-linked immunosorbent assay.

RESULTS

In RSLE patients, plasma nitrite concentrations were significantly higher than in control subjects (P=0.009) and correlated positively with plasma sTM, plasma creatinine and urea (all P<0.05). Plasma sTM and sVCAM-1 concentrations were significantly elevated in RSLE and SLE patients (both P<0.0001) compared with controls. Plasma sTM was significantly correlated with plasma sVCAM-1, and both were correlated with plasma creatinine and urea and the SLE Disease Activity Index (all P<0.05).

CONCLUSION

Elevated plasma NO, sTM, and sVCAM-1 concentrations have significant intercorrelations and are strongly associated with renal involvement in SLE.

Anti-proliferative and differentiation-inducing activities of the green tea catechin epigallocatechin-3-gallate (EGCG) on the human eosinophilic leukemia EoL-1 cell line

A novel approach for the treatment of leukemia is the differentiation therapy in which immature leukemia cells are induced to attain a mature phenotype when exposed to differentiation inducers, either alone or in combinations with other chemotherapeutic or chemopreventive drugs. Over the past decade, numerous studies indicated that green tea catechins (GTC) could suppress the growth and induce apoptosis on a number of human cancer cell lines. However, the differentiation-inducing activity of GTC on human tumors remains poorly understood. In the present study, the effect of the major GTC epigallocatechin-3-gallate (EGCG) on the proliferation and differentiation of a human eosinophilc leukemic cell line, EoL-1, was examined. Our results showed that EGCG suppressed the proliferation of the EoL-1 cells in a dose-dependent manner, with an estimated IC(50) value of 31.5 microM. On the other hand, EGCG at a concentration of 40 microM could trigger the EoL-1 cells to undergo morphological differentiation into mature eosinophil-like cells. Using RT-PCR and flow cytometry, it was found that EGCG upregulated the gene and protein expression of two eosinophil-specific granule proteins, the major basic protein (MBP) and eosinophil peroxidase (EPO), in EoL-1 cells. Taken together, our findings suggest that EGCG can exhibit anti-leukemic activity on a human eosinophilic cell line EoL-1 by suppressing the proliferation and by inducing the differentiation of the leukemia cells.

Elevated production of interleukin-18 is associated with renal disease in patients with systemic lupus erythematosus

To investigate the production mechanism and proinflammatory role of the cytokine interleukin (IL-18) in lupus nephritis, we investigated the plasma concentrations of IL-18 and nitric oxide (NO) and the release of IL-18 and NO from mitogen-activated peripheral blood monomuclear cells (PBMC), in 35 SLE patients with renal disease (RSLE), 37 patients without renal disease (SLE) and 28 sex- and age-matched healthy control subjects (NC). IL-18 and NO concentrations were measured by ELISA and colourimetric non-enzymatic assay, respectively. Gene expressions of IL-18 and IL-18 receptor were analysed by RT-PCR. Plasma IL-18 and NO concentrations were significantly higher in RSLE than NC (both P < 0.01). Elevation of plasma IL-18 in RSLE correlated positively and significantly with SLE -disease activity index and plasma NO concentration (r = 0.623, P < 0.0001 and r = 0.455, P = 0.017, respectively), and the latter also showed a positive and significant correlation with plasma creatinine (r = 0.410, P = 0.034) and urea (r = 0.685, P < 0.0001). There was no significant difference in gene expressions of IL-18 and IL-18 receptor in PBMC among RSLE, SLE and NC. Percentage increase in culture supernatant IL-18 concentration was significantly higher in RSLE than SLE and NC (both P < 0.05). The basal NO release was significantly higher in RSLE than that in SLE and NC (both P < 0.005). IL-18 is therefore suggested to play a crucial role in the inflammatory processes of renal disease in SLE.

Activation of p38 mitogen-activated protein kinase and nuclear factor-kappaB in tumour necrosis factor-induced eotaxin release of human eosinophils

The CC chemokine eotaxin is a potent eosinophil-specific chemoattractant that is crucial for allergic inflammation. Allergen-induced tumour necrosis factor (TNF) has been shown to induce eotaxin synthesis in eosinophils. Nuclear factor-kappaB (NF-kappaB) and mitogen-activated protein kinases (MAPK) have been found to play an essential role for the eotaxin-mediated eosinophilia. We investigated the modulation of NF-kappaB and MAPK activation in TNF-induced eotaxin release of human eosinophils. Human blood eosinophils were purified from fresh buffy coat using magnetic cell sorting. NF-kappaB pathway-related genes were evaluated by cDNA expression array system. Degradation of IkappaBalpha and phosphorylation of MAPK were detected by Western blot. Activation of NF-kappaB was determined by electrophoretic mobility shift assay. Eotaxin released into the eosinophil culture medium was measured by ELISA. TNF was found to up-regulate the gene expression of NF-kappaB and IkappaBalpha in eosinophils. TNF-induced IkappaBalpha degradation was inhibited by the proteasome inhibitor N-cbz-Leu-Leu-leucinal (MG-132) and a non-steroidal anti-inflammatory drug sodium salicylate (NaSal). Using EMSA, both MG-132 and NaSal were found to suppress the TNF-induced NF-kappaB activation in eosinophils. Furthermore, TNF was shown to induce phosphorylation of p38 MAPK time-dependently but not extracellular signal-regulated kinases (ERK). Inhibition of NF-kappaB activation and p38 MAPK activity decreased the TNF-induced release of eotaxin from eosinophils. These results indicate that NF-kappaB and p38 MAPK play an important role in TNF-activated signalling pathway regulating eotaxin release by eosinophils. They have also provided a biochemical basis for the potential of using specific inhibitors of NF-kappaB and p38 MAPK for treating allergic inflammation.

Bounded-depth threshold circuits for computer-assisted CT image classification

We present a stochastic algorithm that computes threshold circuits designed to discriminate between two classes of computed tomography (CT) images. The algorithm employs a partition of training examples into several classes according to the average grey scale value of images. For each class, a sub-circuit is computed, where the first layer of the sub-circuit is calculated by a new combination of the Perceptron algorithm with a special type of simulated annealing. The algorithm is evaluated for the case of liver tissue classification. A depth-five threshold circuit (with pre-processing: depth-seven) is calculated from 400 positive (abnormal findings) and 400 negative (normal liver tissue) examples. The examples are of size n=14,161 (119 x 119) with an 8 bit grey scale. On test sets of 100 positive and 100 negative examples (all different from the learning set) we obtain a correct classification close to 99%. The total sequential run-time to compute a depth-five circuit is about 75h up to 230h on a SUN Ultra 5/360 workstation, depending on the width of the threshold circuit at depth-three. In our computational experiments, the depth-five circuits were calculated from three simultaneous runs for depth-four circuits. The classification of a single image is performed within a few seconds.