The clinical utility of conventional karyotyping in the detection of cytogenetic abnormalities in soft tissue tumours: an Asian institutional experience

OBJECTIVES

To assess the clinical utility of conventional karyotyping as a diagnostic tool in soft tissue tumours amidst the increasing use of molecular cytogenetics.

DESIGN

Case series.

SETTING

Singapore General Hospital, an Asian institution.

PARTICIPANTS

A total of 35 participants (18 male and 17 female) aged 15 to 81 years were included in this study. Conventional karyotyping of 35 consecutive fresh soft tissue tumour specimens was performed over 4 years and the results were analysed.

RESULTS

Of the 35 cases of soft tissue tumours reviewed, chromosome abnormalities were detected in 22 (63%) cases, 11 (31%) showed a normal karyotype, and 2 (6%) had culture failure. Of the 22 cases with abnormal karyotype, nine (41%) cases showed recurring aberrations: Ewing's sarcomas (n=2), desmoplastic small round cell tumour (n=1), synovial sarcomas (n=3), myxoid liposarcomas (n=2), and lipoma (n=1). One lipoma case had a t(2;12)(q23;q15) in which 2q23 breakpoint was not reported before. Chromosomal aberration involving 12q15 breakpoint has been shown in a previous study to be indicative of a lipoma-like liposarcoma. Another lipoma case had addition of 5q15 and 9p13 together with a balanced aberration of t(12;13) (q13;q12) which were novel aberrations. One synovial sarcoma case showed t(3;7)(q21;p13) which was an uncharacteristic aberration.

CONCLUSION

Conventional karyotyping demonstrated utility as a genome-wide screening tool for soft tissue tumours and an adjunct diagnostic tool in the event histopathology results were doubtful. With the more widespread use of karyotyping, novel recurring chromosomal aberrations may be discovered.

An abnormal nonhyperdiploid karyotype is a significant adverse prognostic factor for multiple myeloma in the bortezomib era

Multiple myeloma is clinically heterogeneous and risk stratification is vital for prognostication and informing treatment decisions. As bortezomib is able to overcome several high-risk features of myeloma, the validity of conventional risk-stratification and prognostication systems needs to be reevaluated. We study the survival data of 261 previously untreated myeloma patients managed at our institution, where bortezomib became available from 2004 for the treatment of relapse disease. Patient and disease characteristics, and survival data were evaluated overall, and with respect to bortezomib exposure. Overall, the international staging system (ISS), metaphase karyotyping and interphase fluorescence in situ hybridization (FISH) were discerning of survival outcomes, where the median for the entire cohort was 5.2 years. However, when stratified by bortezomib exposure, only metaphase karyotyping was still discriminating of long-term prognosis. The presence of an abnormal nonhyperdiploid karyotype overrides all other clinical and laboratory parameters in predicting for a worse outcome on multivariate analysis (median survival 2.6 years, P = 0.001), suggesting that bortezomib used at relapse is better able to overcome adverse risk related to high tumor burden (as measured by the ISS) than adverse cytogenetics on conventional karyotyping. Metaphase karyotyping provides additional prognostic information on tumor kinetics where the presence of a normal diploid karyotype in the absence of any high-risk FISH markers correlated with superior survival and could act as a surrogate for lower plasma cell proliferation.

Enhancement of neutrophil function by the bronchial epithelium stimulated by epidermal growth factor

The bronchial epithelium is an important physical barrier that regulates physiological processes including leukocyte trafficking. The aim of the present study was to elucidate the mechanisms whereby the bronchial epithelium, stimulated by epidermal growth factor (EGF) as part of a response to acute or chronic injury, could activate and chemoattract human neutrophils. Subconfluent human bronchial epithelial (16HBE) cells were stimulated with EGF to mimic the in vivo events after injury. The effect of the resulting EGF-conditioned media (CM) was compared with that of basal-CM with respect to neutrophil activation and chemotaxis. Such findings were then confirmed using primary bronchial epithelial cells (PBECs) from healthy volunteers. EGF-CM from 16HBE cells caused increased expression of CD11b/CD66b and CD62L loss on neutrophils when compared with basal-CM. EGF-CM contained significant neutrophil chemotactic activity involving granulocyte-macrophage colony-stimulating factor and interleukin-8 that was potentiated by leukotriene B(4). This was dependent on neutrophil phosphatidylinositol-3-kinase activation and Akt phosphorylation, with partial regulation by phospholipase D, but not mammalian target of rapamycin. Consistent with these observations, EGF-CM derived from PBECs displayed increased chemotactic activity. The present results suggest that the enhanced chemotactic activity of the epidermal growth factor-conditioned epithelium can enhance neutrophil-mediated immunity during acute injury, while during continued injury and repair, as in chronic asthma, this could contribute to persistent neutrophilic inflammation.

The novel use of the human nasal epithelial cell line RPMI 2650 as an in vitro model to study the influence of allergens and cytokines on transforming growth factor-beta gene expression and protein release

BACKGROUND

The epithelial accumulation of mast cells is a feature of allergic rhinitis and this has been linked to the expression of the known mast cell chemoattractant transforming growth factor-beta (TGF-beta) at this site. Little is known concerning the regulation of TGF-beta gene expression or protein release by nasal epithelial cells. To address this we have utilized the RPMI 2650 human nasal epithelial cell line, which has some features that closely resemble normal nasal epithelium and has been reported to secrete a TGF-beta-like molecule.

OBJECTIVES

To investigate the regulation of TGF-beta gene expression and protein secretion in RPMI 2650 nasal epithelial cells following exposure to allergens (house dust mite (HDM) and grass pollen) and mast cell associated T-helper type 2 (Th2) cytokines (IL-4, IL-13, and TNF-alpha). Methods Light and scanning electron microscopy was used to evaluate the morphology of RPMI 2650 cells in culture, enzyme-linked immunosorbent assay was used to investigate their TGF-beta secretory capacity and the identification of the TGF-beta isotype(s) involved, flow cytometry was used to demonstrate the presence of TGF-beta receptors on the RPMI 2650 cells, and the quantitative real-time TaqMan PCR was used to measure TGF-beta gene expression.

RESULTS

TGF-beta(2) was identified as the main isotype secreted by the RPMI 2650 cells. HDM allergens and TNF-alpha increased both TGF-beta gene expression and protein release from these cells, whereas grass pollen, IL-4, and IL-13 were without effect.

CONCLUSIONS

The RPMI 2650 nasal epithelial cell line represents a valid in vitro model to evaluate the regulation of TGF-beta biology. In this system HDM allergens have stimulatory activity that is fundamentally different from that of grass pollen allergens, and the Th2 cytokines IL-4 and IL-13 are without effect. The ability of TNF-alpha to up-regulate both TGF-beta gene expression and protein release indicates that mast cell-epithelial interactions concerning TGF-beta are bi-directional and this may be fundamental to epithelial immunoregulation. The availability of a model system, such as the RPMI 2650 cells, will enable the early evaluation of future novel and targeted interventions directed toward the aberrant responses of upper airway structural cells.

Nasal lavage fluid concentrations of eotaxin-1 (CCL11) in naturally occurring allergic rhinitis: relationship to disease activity, nasal luminal eosinophil influx, and plasma protein exudation

BACKGROUND

Eotaxin-1 (CCL11) is a CC chemokine whose nasal eosinophilic chemotactic activity in vivo and in vitro has been demonstrated primarily using nasal allergen challenge models. The extension of these challenge findings to the in vivo setting has been limited.

OBJECTIVE

To obtain nasal lavage fluid from volunteers with perennial and seasonal (in- and out-of-season) allergic rhinitis (AR) and non-atopic non-rhinitic controls for the measurement of eotaxin-1 concentrations and to relate these findings to the symptomatic disease severity, the percentage of lavage eosinophils, and to alpha(2)-macroglobulin (alpha(2)-MG) lavage concentrations, as a marker of vascular permeability and an index of airway inflammation.

METHODS

Thirty-seven volunteers with AR (16 seasonal and 21 perennial) and 20 non-atopic non-rhinitic volunteers were recruited and phenotyped. Nasal lavage fluid was obtained by standardized protocol. The nasal lavage fluid concentrations of eotaxin and alpha(2)-MG were measured by ELISA, and differential cell counts performed on cytospins.

RESULTS

Eotaxin-1 nasal lavage fluid concentrations were significantly higher in both the perennial and seasonal (in-season) AR groups compared with the controls, and significantly related to the severity of symptom expression and to the percentage of lavage eosinophils. The lavage eosinophil counts were significantly higher in both the symptomatic rhinitis groups compared with the control groups and correlated with the lavage concentrations of alpha(2)-MG. alpha(2)-MG levels were significantly increased in seasonal (in-season) rhinitics compared with both non-atopic controls and seasonal (out-of-season) rhinitics. A significant correlation was observed between the levels of alpha(2)-MG and levels of eotaxin in the symptomatic allergic rhinitic groups.

CONCLUSIONS

This study clearly demonstrates the relevance of eotaxin-1 to the pathogenesis of naturally occurring AR.

Evidence of mast-cell activation in a subset of patients with eosinophilic chronic obstructive pulmonary disease

Although asthma has been viewed mainly as an eosinophilic disease, and chronic obstructive pulmonary disease (COPD) as a neutrophilic disease, recent studies have shown increased neutrophil counts in severe asthma and sputum eosinophilia in some COPD patients. In an attempt to further characterise these two syndromes according to pathology, the current authors have conducted a study of induced sputum in 15 subjects with COPD, 17 asthmatics, and 17 nonatopic healthy individuals. Sputum was analysed for cytology and levels of eosinophil cationic protein (ECP), albumin, tryptase and soluble intercellular adhesion molecule-1. The COPD subjects differed from the asthmatics as they had higher sputum neutrophil and lower columnar epithelial cell counts, but there were no differences in any soluble marker studied. When compared to control subjects, both the asthmatic and COPD subjects had raised eosinophil counts and ECP levels. In a subset of COPD subjects with sputum eosinophilia (>3% of total cells), significantly increased levels of tryptase were detected. In conclusion, although chronic obstructive pulmonary disease is a more neutrophilic disease than asthma, the two diseases are difficult to distinguish on the basis of sputum levels of the soluble markers traditionally associated with asthma. However, a subset of patients with chronic obstructive pulmonary disease with airway eosinophilia and mast-cell activation might represent a distinct pathological phenotype.

Sero-epidemiology and risk factors of positive hepatitis B surface antigen amongst Chinese adolescents

This paper reports the prevalence rate of hepatitis B antigen (HBsAg) amongst the Hong Kong Chinese adolescents (age 11 to 19), and the risk factors associated with HBsAg positive. The study is cross sectional and 1,580 students were randomly selected from 12 secondary schools in four regions of Hong Kong. For those subjects who agreed to participate and were randomly selected, their blood was tested for HBsAg and anti-HBs. The overall prevalence of HBsAg positive was reported to be 5.8% (7.9% in male and 4.1% in female), lower than 8.1% in 1978. Males, those born in Mainland China and family history of carriers had higher prevalence of HBsAg positive (7.9% vs 4.1%, 12.2% vs 4.7%, 52.9% vs 3.8% respectively) with statistical significance. Males and those born in mainland China were found to have significantly higher odds ratio 1.8 (95% CI. 0.98-3.52) and 4.4 (95% CI. 2.2-8.8) respectively of HBsAg positive by multivariate analysis. Findings suggest that family history of carriers and those born in endemic area are at a higher risk. Therefore it is worthwhile to consider vaccination programme for adolescents to reduce the carrier rate, and to also reduce the injection amongst the adults by horizontal transmission.

Generation of cytokine-induced killer cells from leukaemic samples with in vitro cytotoxicity against autologous and allogeneic leukaemic blasts

Cytokine-induced killer (CIK) cells are CD3(+)CD56(+) non-major histocompatibility complex (MHC)-restricted immune effector cells. The present report demonstrates that it was possible to expand CIK cells obtained at diagnosis from patients with acute leukaemia. The percentage of CD3(+)CD56(+) CIK cells generated following culture ranged between 7.6% and 65% (median of 35.3%) and these cells were able to kill the human natural killer target K562 cells. Although the same effector cells were able to lyse autologous acute myeloid leukaemia (AML) target cells, they were not able to lyse autologous acute lymphoblastic leukaemia target cells. Pre-absorption of the CIK effector cells by K562 cells did not completely abrogate the cytotoxicity of CIK cells against autologous blasts in 9 out of 12 samples tested. Moreover, it was observed that the cytotoxicity generated by the CIK effector cells against allogeneic leukaemic blasts was similar to that against autologous blasts. The present study suggests the potential application of CIK cells in the immunotherapy of AML, either in minimal disease state, as donor lymphocyte infusion in relapse post allogeneic transplant, or in cases of chemotherapy refractory leukaemia.

Pseudodicentric (16;12)(q11;p11.2) in a type AB (mixed) thymoma

Genetic alterations of thymomas are rarely described in the literature. In this study, a previously unreported instance of aberrant karyotypic change consisting of 45,XX,pseu dic(16;12) (q11;p11.2) [cp23]/87-90,idemx2[cp4] in a Masaoka Stage II mixed thymoma or type AB thymoma affecting a 56-year-old Chinese woman is detailed. Abnormalities involving 12p containing important tumor suppressor-like genes have been documented especially in hematological malignancies. Recently, recurrent losses involving 16q, a locus known to harbor several tumor suppressor genes, have been described in type C thymomas (squamous cell carcinoma), suggesting a possible relationship between type AB thymoma and type C thymoma. Whether these genes are involved in the pathogenesis of type AB thymoma remain to be clarified and it is currently unclear if cytogenetic studies may eventually play a role in the classification of thymic tumors.

Induction of type 2 activity in adult human CD8(+) T cells by repeated stimulation and IL-4

Repeated administration or chronic presence of antigen during CD4(+) T cell activation and a cytokine milieu enriched in IL-4 favour the generation and maintenance of a T(h)2 population. However, there is little data on how these factors affect adult human CD8(+) T cell functions. We established in vitro conditions to culture purified human CD8(+) T cells, and investigated how repeated stimulation and exogenous IL-4 modulated their functions. Repeated TCR-CD3 stimulation of CD8(+) T cells increased the number of CD25-, CD30- and CD40 ligand-expressing cells, and their capacity to secrete IL-4 and IL-5. In addition, repeatedly stimulated CD8(+) T cells had cytotoxic activity and provided help to resting B cells for IgE synthesis. The presence of exogenous IL-4 during repeated stimulation further increased the number of CD25(+) and CD30(+) CD8(+) T cells, up-regulated the number of IL-5(+) cells, and increased IL-5 levels released. These observations demonstrate that repeated TCR-CD3 stimulation of normal human CD8(+) T cells favoured the growth of cells with a type 2 phenotype and that this was further amplified by the presence of IL-4. These mechanisms may be important in virus-induced lung eosinophilic inflammation in healthy subjects and virus-induced exacerbations of asthma.

Oxytocics reverse the tocolytic effect of glyceryl trinitrate on the human uterus

OBJECTIVES

To investigate the effect of glyceryl trinitrate on isolated human pregnant uterine strips and whether the uterine relaxation induced by glyceryl trinitrate could be reversed by oxytocics used in current clinical practice.

DESIGN

In vitro pharmacological study.

SETTING

Department of Obstetrics & Gynaecology, National University of Singapore, National University Hospital.

PARTICIPANTS

Eighteen women who delivered by caesarean section at term.

METHODS

Myometrial strips were preloaded with an initial tension of 1.5g in organ baths containing Krebs-Henseleit solution which was aerated with oxygen in 5% carbon dioxide and maintained at 37 degrees C, pH 7.4. The effect of glyceryl trinitrate was studied in strips displaying regular spontaneous contractions. The ability of oxytocin, ergometrine or prostaglandin F2alpha to stimulate uterine contractions was assessed in strips where uterine activity was significantly inhibited by glyceryl trinitrate.

RESULTS

Glyceryl trinitrate reduced the amplitude and frequency of spontaneous uterine contractions in a concentration-dependent manner, although the sensitivity of the myometrial strips varied considerably from one specimen to another. The concentration of glyceryl trinitrate producing complete inhibition of myometrial contractions ranged from 44-705 microM. In the presence of glyceryl trinitrate which markedly depressed spontaneous contractions, oxytocin (20 mU/mL), ergometrine (6.15 microM) and prostaglandin F2alpha (6.15 microM) were capable of reversing the uterine activity to either higher than or the untreated level of contractility.

CONCLUSIONS

This study demonstrates that glyceryl trinitrate is a potent uterine relaxant in vitro and that the tocolytic effect could be reversed with ease by oxytocics.

Cytogenetic analysis of invasive breast cancer: a study of 27 Asian patients

Tumor cytogenetic analysis from 27 patients with breast cancer diagnosed at the Singapore General Hospital revealed complex karyotypic aberrations in 12 cases. The study group comprised 25 women and 2 men, ranging in age from 33 to 78 years (median 52 years). Ethnic distribution consisted of 22 Chinese, 3 Malaysian, and 2 Indian patients. Pathologic assessment disclosed 24 invasive ductal, 2 invasive mucinous, and 1 mixed invasive mucinous and ductal carcinomas. Histologic grading showed 3 grade 1, 10 grade 2, and 12 grade 3 tumors; 2 cancers were not graded, because they had been subjected to prior chemotherapy. Tumor sizes ranged from 1.5 to 10 cm (median 3 cm). Eleven cases were axillary node negative, whereas the remaining 16 node-positive cancers affected as many as 3 nodes in 8 cases and 4 or more nodes in another 8. Twenty cases demonstrated estrogen-receptor positivity, and 8 cases progesterone-receptor positivity. The spectrum of cytogenetic abnormalities involved chromosomes 1, 3, 6, 7, 8, 11, 16, and 17 and ranged from gains and deletions of both long and short arms, trisomy, monosomy, and other rearrangements. There was a trend toward the presence of karyotypic abnormalities in tumors of higher grade.

Effects of short-term exposure to 0.2 ppm ozone on biomarkers of inflammation in sputum, exhaled nitric oxide, and lung function in subjects with mild atopic asthma

To gain further insight into the kinetics of airway inflammatory response and explore the possibility of nitric oxide as a surrogate marker of the lower airway inflammatory response to ozone, nine subjects with mild atopic asthma were exposed to filtered air or 0.2 ppm ozone for 2 hours with intermittent exercise. Lung function was measured at baseline and immediately after exposures. Sputum induction was performed at 6 hours and at 24 hours after exposures, and exhaled nitric oxide levels were measured at baseline, immediately, 6, and 24 hours after both exposures. A significant decline in forced expiratory volume in one second and inspiratory capacity was detectable following exposure to ozone. In addition, a 2-fold increase was observed in the percentage of polymorphonuclear leukocytes 6 hours after exposure to ozone, with no changes in other biomarkers at this time point. By 24 hours after ozone exposure, the neutrophilia had subsided but there was an increase in albumin, total protein, myeloperoxidase, and eosinophil cationic protein. Exhaled nitric oxide levels, histamine, interleukin-8, and growth-related oncogene-alpha in sputum did not change significantly following ozone exposure. It was concluded that short-term ozone exposure induces an acute inflammatory response in asthmatic airways, characterized by early polymorphonuclear leukocyte influx followed by plasma extravasation and activation of eosinophils and neutrophils. Exhaled nitric oxide is not a useful marker for detecting inflammatory response to ozone in persons with mild asthma.

Philadelphia positive acute lymphoblastic leukaemia (ALL): clinico-haematologic characteristics, molecular analyses and 3-year follow up--a single institution study

INTRODUCTION

The Philadelphia chromosome is one of the commonest chromosomal aberration in adult acute lymphoblastic leukaemia (ALL) patients. We present the results of a 3-year prospective study to look at the clinico-haematologic, immunophenotypic, cytogenetic and molecular profile of 13 adult patients with Philadelphia (Ph) positive ALL out of 35 newly diagnosed ALL seen at our institution over the past 3 years.

MATERIALS AND METHODS

Thirty-five adult ALL patients seen between 1996 and 1998 comprised the study group. Marrow samples were obtained for immunophenotyping and karyotypic analysis at diagnosis. Samples were also obtained simultaneously for molecular testing for Ph chromosome.

RESULTS

Thirteen patients were found to be Ph positive by molecular analysis while cytogenetic studies identified the chromosomal abnormality in 9 of these patients. The median age of our Ph positive patients was similar to those without Ph chromosome. Pre-B phenotype appears to be common in this group of patients. In concordance with other studies, Ph positive ALL was associated with a poor prognosis in our patients.

CONCLUSION

Identification of Ph chromosome is important in the management of patients with ALL as it is an important prognostic marker.

The relationship between airways inflammation and asthma severity

In order to investigate the relationship between airways inflammation and disease severity, and improve the understanding of persistent asthma, 74 asthmatics, with disease severity ranging from intermittent, to mild to moderate and severe persistent (classified according to the Global Initiative for Asthma [GINA] guidelines), and 22 nonatopic control subjects were studied using the method of induced sputum. Sputum was analyzed for total and differential cell counts concentrations of albumin, and levels of eosinophil cationic protein (ECP), myeloperoxidase (MPO), and tryptase, inflammatory mediators reflecting eosinophil, neutrophil, and mast cell activation. Asthma severity (assessed by FEV(1), peak expiratory flow [PEF] variability, and daily symptom scores) and methacholine airways responsiveness were related to sputum eosinophilia and ECP. In addition, sputum neutrophilia and MPO levels correlated, albeit weakly, with PEF variability and symptom scores, respectively. Tryptase concentrations were raised in mild to moderate asthmatics. Albumin concentrations were significantly raised across the spectrum of asthma severity and correlated with those of tryptase and ECP. Despite treatment with either high doses of inhaled corticosteroids or oral corticosteroids, prominent eosinophilic inflammation with raised ECP was noted. This study points to persistent, disease severity-related airways inflammation in asthma, involving eosinophils, mast cells, and neutrophils, which is evident despite treatment with corticosteroids.

Molecular and phenotypic spectrum of de novo Philadelphia positive acute leukemia

The Philadelphia chromosome is present in a heterogeneous group of leukemias. It is most commonly associated with chronic myelogenous leukemia (CML) and B-lineage acute lymphoblastic leukemia (ALL) being found in more than 95% and 15-25% of cases respectively. We undertook a study to determine the morphologic, phenotypic and molecular diversity of Philadelphia positive de novo acute leukemia patients seen at our institution over the past 3 1/2 years. Twenty-one patients with de novo acute leukemia were found to have the Philadelphia chromosome by cytogenetic studies. They consisted of 3 patients with acute myelogenous leukemia (AML), 1 biphenotypic leukemia and 17 ALL patients. Of the patients with ALL, 16 were of B-lineage while 1 had a T-cell phenotype. Ten patients expressed the p210 BCR-ABL transcript alone and 10 expressed only the p190 BCR-ABL transcript. One patient had co-expression of p190 and p210 b3a2 BCR-ABL transcripts. Thus the Philadelphia chromosome can be found in a diverse cohort of morphologic and immunologic subtypes of de novo acute leukemia reflecting the heterogeneity of lineage involvement in this disease.

The effect of propofol on human gastric and colonic muscle contractions

Although propofol is widely used for sedation in the intensive care unit, there are limited data on its effects on gastrointestinal motility. For that reason, we studied the in vitro effects of propofol on human gastric and colonic smooth muscle. Grossly normal human gastric and colonic muscle strips were mounted in an organ bath set-up for isometric contraction and stimulated by acetylcholine (Ach), using a cumulative dose schedule in the absence or presence of different concentrations of propofol [1.7 x 10(-6) M (0.3 microg/mL) to 4.4 x 10(-4) M (78 microg/mL)]. Ach led to concentration-dependent contraction of both gastric and colonic muscle strips, whereas propofol, at a concentration 6.7 x 10(-6) M (1.2 microg/mL) and above, significantly depressed Ach-induced contraction in a concentration-dependent manner for both smooth muscle preparations. In addition, propofol, at a concentration 2.7 x 10(-5)M (4.8 microg/mL) and above, depressed spontaneous contractile activity of both smooth muscle preparations. Fat emulsion 10% (Intralipid), the solvent for propofol, had no effect on either the spontaneous activity or the Ach-induced contraction of gastric and colonic smooth muscles.

IMPLICATIONS

The success of enteral feeding requires a normal gastrointestinal motility. We found that, at clinically relevant concentrations, propofol impaired gastrointestinal contractile activity. Further investigations are required to determine the clinical significance of this change.

The effect of propofol on human gastric and colonic muscle contractions

Although propofol is widely used for sedation in the intensive care unit, there are limited data on its effects on gastrointestinal motility. For that reason, we studied the in vitro effects of propofol on human gastric and colonic smooth muscle. Grossly normal human gastric and colonic muscle strips were mounted in an organ bath set-up for isometric contraction and stimulated by acetylcholine (Ach), using a cumulative dose schedule in the absence or presence of different concentrations of propofol [1.7 x 10(-6) M (0.3 microg/mL) to 4.4 x 10(-4) M (78 microg/mL)]. Ach led to concentration-dependent contraction of both gastric and colonic muscle strips, whereas propofol, at a concentration 6.7 x 10(-6) M (1.2 microg/mL) and above, significantly depressed Ach-induced contraction in a concentration-dependent manner for both smooth muscle preparations. In addition, propofol, at a concentration 2.7 x 10(-5)M (4.8 microg/mL) and above, depressed spontaneous contractile activity of both smooth muscle preparations. Fat emulsion 10% (Intralipid), the solvent for propofol, had no effect on either the spontaneous activity or the Ach-induced contraction of gastric and colonic smooth muscles.

IMPLICATIONS

The success of enteral feeding requires a normal gastrointestinal motility. We found that, at clinically relevant concentrations, propofol impaired gastrointestinal contractile activity. Further investigations are required to determine the clinical significance of this change.

Congenital acute megakaryoblastic leukemia (M7) with chromosomal t(1;22)(p13;q13) translocation in a set of identical twins

Chromosomal translocations at t(1;22)(p13;q13) have been reported to occur in a number of infants with acute megakaryoblastic leukemia. A set of female twins with acute megakaryoblastic leukemia are reported with this unique translocation of 1p13 to 22q13. The twins presented at 2 months of age with fever and poor feeding and subsequently developed progressive hepatosplenomegaly. One twin died before treatment could be started; the other became septicemic 5 days after initiation of chemotherapy and eventually died.

The effect of processing on inflammatory markers in induced sputum

The effects of the mucolytic agent, dithioerythritol (DTE), and the temperature at which sputum processing is conducted on cellular and biochemical markers in induced sputum was assessed. Samples from healthy and atopic asthmatic subjects were treated with either DTE or phosphate-buffered saline (PBS) at 22 or 37 degrees C and compared for cell counts and concentrations of histamine, tryptase, eosinophil cationic protein (ECP), free interleukin (IL)-8, immunoglobulin (Ig)A, IL-8/IgA complexes and secretory component (SC). In addition, the influence of DTE on in vitro mediator release from blood eosinophils, basophils and bronchoalveolar lavage (BAL) mast cells was studied. Processing with DTE improved cytospin quality and increased the cell yield and measurable ECP, tryptase, IgA and SC, but reduced levels of histamine in PBS-treated samples and had no effect on IL-8. Cell counts or mediator levels were similar when sputum was processed at 22 or 37 degrees C, even though DTE induced blood basophils and BAL mast cells to release histamine at 37 degrees C. In spiking experiments, recovery of added ECP, tryptase, total IL-8 and histamine from sputum was similar in DTE- and PBS-processed sputum, but reduced for free IL-8 in PBS-treated samples. In conclusion, dithioerythritol improves cell and mediator recovery without causing cell activation when sputum processing is conducted at room temperature. The extent of recovery depends on the mediator studied.

Effect of systemic beta-agonist therapy on IgE production in allergic subjects in vivo

BACKGROUND

Although beta2-adrenoceptor agonists are widely used in the treatment of asthma, a number of studies have suggested that their long-term use may exacerbate the condition. One possible mechanism for this stems from the in vitro observation that beta2-agonists increase IgE synthesis by human blood mononuclear cells.

OBJECTIVE

We sought to examine the effect of regular beta2-agonist therapy on IgE production in vivo in human volunteers.

METHODS

Placebo or salbutamol (8 mg BD) tablets were given in a double-blind, randomized fashion to 25 volunteers allergic to grass pollen throughout a period encompassing the UK grass pollen season (April through September). Levels of serum IgE were measured monthly, and nasal IgE was measured at the height and end of the season. Efficacy was assessed through monthly recordings of symptoms of blocked nose (vascular) and other symptoms of rhinitis (nonvascular).

RESULTS

For the whole group the geometric mean of serum IgE levels rose from a baseline of 58.7 IU/mL (range, 0 to 1027 IU/mL) to 140 IU/mL (range, 12 to 878 IU/mL) at the height of the pollen season (P =.0001). There was no significant difference between the magnitude of the rise in IgE between the groups with a ratio of increase for salbutamol/placebo of 1.17 (confidence interval = 0.78 to 1.75). There was no change in nasal IgE levels. Total and nonvascular symptom scores were reduced by salbutamol, reaching statistical significance at the height of the pollen season (P <.05).

CONCLUSION

An oral dose of the beta2-agonist salbutamol, sufficient to maintain therapeutic levels and provide clinical benefit, does not accentuate the seasonal increase of IgE in human atopic volunteers.

Acute promyelocytic leukemia with a dicentric chromosome involving chromosomes 11, 17, and 18

We report a case of acute promyelocytic leukemia with dicentric chromosome resulting from translocation of chromosomes 11, 17, and 18.

Highly complex chromosomal rearrangement of chromosome 9 in a case of chronic myeloid leukemia

A 63-year-old man with chronic myeloid leukemia (CML) was found to have a new complex Philadelphia translocation. All of the bone marrow cells had a rearrangement of a five-way translocation, t(9;22;10;12;1), involving a single chromosome 9. The patient went into blast crisis two years after initial diagnosis and the karyotype remained unchanged. He died in blast crisis 10 months later. We believe this case is a unique 5-way translocation in which four chromosomes were translocated to a single chromosome.

Effects of 0.2 ppm ozone on biomarkers of inflammation in bronchoalveolar lavage fluid and bronchial mucosa of healthy subjects

Short-term exposure to ozone at peak ambient levels induces neutrophil influx and impairs lung function in healthy humans. In order to investigate the mechanisms contributing to neutrophil recruitment and to examine the role of T-cells in the acute inflammatory response, we exposed 12 healthy humans to 0.2 parts per million (ppm) of ozone and filtered air on two separate occasions for 2 h with intermittent periods of rest and exercise (minute ventilation = 30 L x min(-1)). Fibreoptic bronchoscopy was performed 6 h after the end of exposures. Total protein, tryptase, histamine, myeloperoxidase, interleukin (IL)-8 and growth-related oncogene-alpha (Gro-alpha) were measured and total and differential cell counts were performed in bronchoalveolar lavage (BAL) fluid. Flow cytometry was performed on BAL cells to study total T-cells, T-cell receptors (alphabeta and gammadelta), T-cell subsets (CD4+ and CD8+ cells) and activated T-cell subsets (CD25+). Using immunohistochemistry, neutrophils, mast cells, total T-cell numbers, T-cell subsets, CD25+ T-cells and leukocyte endothelial adhesion molecules including P-selectin, E-selectin, intercellular adhesion molecule (ICAM)-1 and vascular adhesion molecule (VCAM)-1 were quantified in the bronchial biopsies. Paired samples were available from nine subjects. Following ozone exposure there was a threefold increase in the proportion of polymorphonuclear neutrophils (PMNs) (p=0.07) and epithelial cells (p=0.05) in BAL fluid. This was accompanied by increased concentrations of IL-8 (p=0.01), Gro-alpha (p=0.05) and total protein (p=0.058). A significant positive correlation was demonstrated between the two chemokines and proportion of PMNs in BAL fluid. After ozone exposure there was a significant decrease in the CD4/CD8 ratio (p=0.05) and the proportion of activated CD4+ (p=0.01) and CD8+ T-cells (p=0.04). However, no significant changes were demonstrable in any of the inflammatory markers studied in the biopsies. Short-term exposure of healthy humans to 0.2 ppm ozone induced a neutrophil influx in peripheral airways at 6 h post exposure, but no apparent inflammatory response in proximal airways. This response seems to be mediated at least in part by interleukin-8 and growth-related oncogene-alpha.

A case of t(8;14) with total and partial trisomy 3 in Waldenstrom macroglobulinemia

A case of Waldenstrom macroglobulinemia with Burkitt-type t(8;14)(q24.1;q32) and total and partial trisomy 3 is reported. This is an unusual combination of chromosomal abnormalities in Waldenstrom macroglobulinemia.

Interaction of kunjin virus with octyl-D-glucoside extracted Vero cell plasma membrane

Initial experiments using whole cells have shown that there were specific and saturable interactions between kunjin (KUN) virus and receptor molecules on the Vero cell surfaces. Solubilisation of Vero cell plasma membranes with octyl-D-glucoside (OG) yielded an extract which also interacted specifically with KUN virus. This was proven using electron microscopy. When the virus-OG-extract complex was exposed onto Vero cell monolayers, no KUN virus was observed to enter into the whole cells. This would imply that there was virus-receptor interaction with the OG-extract leaving no free virus to attach to the whole cells. The attachment kinetics of KUN virus was studied further using the Scatchard analysis which indicated the involvement of more than one interactive macromolecule in the attachment event.

Effects of bupivacaine and its isomers on guinea pig tracheal smooth muscle

The effects of racemic bupivacaine and its (-)-(S)- and (+)-(R)-isomers on guinea pig tracheal smooth muscle tension were studied in vitro. Racemic bupivacaine had a dual action with contraction at low concentrations (6.9-55 x 10(-6) M) and relaxation at high concentrations (1.1-18 x 10(-4) M), (-)-(S)-Bupivacaine had dual action comparable to that of racemic bupivacaine, while (+)-(R)-bupivacaine had only weak contractile effects with more marked relaxant effects. The contractile effects of bupivacaine were abolished in Ca(2+)-free medium and by verapamil, while the relaxant effects were not influenced by verapamil or Ca(2+)-free medium. The (-)-(S)-isomer is responsible for the contractile effects of racemic bupivacaine, whereas both (-)-(S)- and (+)-(R)-isomers contribute to its relaxant effects. In preparations denuded of epithelium, the (maximal) responses were attenuated to 86% of maximum contraction and 48% of maximum relaxation, suggesting that the epithelium plays a larger role in relaxant than in contractile responses to bupivacaine. It is concluded that bupivacaine has a dual action on guinea pig tracheal smooth muscle with epithelium-independent. Ca(2+)-dependent contraction at low concentrations and epithelium-dependent, Ca(2+)-independent relaxation at higher concentrations.

Inhibition of histamine and eicosanoid release from dispersed human lung cells in vitro by quinotolast

We have examined the effects of a new anti-allergic drug, quinotolast [sodium 5-(4-oxo-1-phenoxy-4H-quinolizine-3-carboxamido) yetrazolate monohydrate], in inhibiting the release of histamine and the generation of leukotriene (LT) C4 and prostaglandin (PG) D2 from dispersed human lung cells and compared this with those of its active metabolite in the rat, hydroxy quinotolast, and reference drugs, tranilast and sodium cromoglycate (SCG). Quinotolast in the concentration range of 1-100 micrograms/ml inhibited histamine and LTC4 release in a concentration-dependent manner. The inhibitory effect of quinotolast on histamine release from dispersed lung cells was largely independent of the preincubation period, no tachyphylaxis being observed. Hydroxy quinotolast and tranilast showed a weak inhibition of histamine release only when the drugs were added to the cells simultaneously with anti-IgE challenge. Quinotolast, 100 micrograms/ml, and SCG, 1 mM, significantly inhibited PGD2 and LTC4 release. Quinotolast inhibited PGD2 release by 100% and LTC4 release by 54%, whereas SCG inhibited PDG2 release by 33% and LTC4 release by 100%. No cross-tachyphylaxis between quinotolast and SCG was observed. The results demonstrated that quinotolast showed a significant inhibition of inflammatory mediators from human dispersed lung cells, suggesting that quinotolast is a good candidate for a clinical anti-allergic drug.

Endothelin in bronchoalveolar lavage fluid and its relation to airflow obstruction in asthma

Endothelins (ETs) are a family of peptide mediators that have a number of biological properties, including the ability to act as potent bronchoconstrictors of isolated human airways. To examine the possible involvement of ET in asthma, we have performed fiberoptic bronchoscopy and bronchoalveolar lavage (BAL) on 10 healthy control subjects, 10 patients with atopic asthma treated with bronchodilators alone, and 8 patients with atopic asthma treated with inhaled and/or oral corticosteroids. Endothelin concentrations in BAL fluid were measured by radioimmunoassay and total protein concentrations by a colorimetric method. There was a significant increase in the BAL fluid ET levels in the non-steroid-treated patients with asthma compared with the normal subjects, when expressed either as a concentration (median, 0.30 versus 0.08 pM; p = 0.001) or in relation to total protein (median, 3.02 versus 1.08 pmol/g; p = 0.01). There was, however, no statistically significant difference in ET levels between the steroid-treated patients with asthma, and either of the other two groups. In the non-steroid-treated patients with asthma there was a significant negative correlation between the BAL fluid ET concentration and the % predicted FEV1 (r = -0.71, p = 0.03). This correlation was not significant in the steroid-treated subjects, and no correlation between BAL fluid ET concentrations and bronchial reactivity was found in any of the three groups. These findings are consistent with the hypothesis that ET contributes to the pathophysiology of asthma.

Cytogenetic abnormalities in childhood acute lymphoblastic leukaemia

A retrospective study of 50 children newly diagnosed with acute lymphoblastic leukaemia (ALL) from December 1988 to November 1993 was carried out, examining the disease conditions and cytogenetic abnormalities. Of the 50 children, 8 had no cytogenetic examination of the marrow at the time of diagnosis and 7 had a poor yield from the marrow. Fifty percent of the remaining children had a normal karyotype. The rest of the children had hyperdiploidy and structural chromosomal abnormalities (mainly translocation and deletions) in equal proportions. Overall mortality of the whole group was about 26% with 2 lost to follow-up. There were 2 patients who relapsed while on treatment of whom 1 died. Cytogenetic abnormalities were correlated with clinical variables known to have prognostic significance. The group with hyperdiploidy had a significantly lower mean total white count at presentation and none of them died. The group with translocation abnormalities had a lower mean platelet count at presentation. Almost all in the group with hyperdiploidy and a great majority of the other 2 groups with normal or structural cytogenetic abnormalities were of B cell lineage. The median survival times for the hyperdiploid, normal karyotype and translocation patients were 1800 days, 1450 days and 700 days respectively.

Amplified rhinovirus colds in atopic subjects

Evidence suggests that atopic individuals may be predisposed to more severe rhinoviral colds coupled to a worsening of existing airway disease than those with asthma. The role of atopy and IgE levels, as well as their relationship to clinical disease expression have not been defined. We hypothesized that an allergic diathesis modulates rhinoviral colds and have initiated studies of normal, atopic and asthmatic subjects employing experimental rhinoviral infection, with measurements of symptom scores, viral shedding and cultures, albumin in nasal washes and serological responses. Twenty-two subjects (11 normal, 5 atopic, 6 atopic and asthmatic) participated and were inoculated with human rhinovirus serotype 16 (HRV 16). Measurements of neutralizing antibody and viral culture were performed at screening, pre-inoculation, during the cold and at 8-10 weeks convalescence. Daily symptoms were noted, nasal washes done, IgE measured and atopy was diagnosed by skin tests. Seventeen volunteers developed clinical colds as assessed by symptom scores, virus shedding was demonstrated (with positive culture) in all subjects and a fourfold or higher seroconversion occurred in 11/22. Neutralizing HRV antibody developed unexpectedly in 10 subjects between screening and inoculation and the presence of absence of this pre-inoculation antibody determined subsequent severity of colds in normal but not in atopic subjects. Atopic antibody positive individuals developed severe clinical colds that were independent of preinoculation antibody in contrast to normal subjects who developed mild colds in the presence of a neutralizing antibody (P = 0.01). Both atopic and normal antibody negative subjects developed severe colds.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of local hyperthermia on allergen-induced nasal congestion and mediator release

BACKGROUND

Local hyperthermia reduces mast cell degranulation, the severity of acute lung injury, and exercise-induced asthma and decreases symptoms of rhinitis. We have investigated the effect of local hyperthermia on mast cell degranulation and symptom generation in allergic rhinitis to assess its effect and mechanism of action within the nose.

METHODS

In a randomized, double-blind, placebo-controlled, crossover study, 10 subjects with rhinitis were treated for 30 minutes with local hyperthermia or placebo, which was followed 30 minutes later by nasal allergen challenge. During the first two visits nasal lavages were performed to assess vascular leakage and mediator release. During the last two visits nasal airway resistance, the number of sneezes, and mucus secretion were monitored.

RESULTS

Local hyperthermia significantly reduced both nasal airway resistance (p < 0.05) and vascular leakage (p < 0.02) but had no significant effect on the number of sneezes, on mucus secretion, or on tryptase release.

CONCLUSION

Local hyperthermia reduces allergen-provoked nasal blockage and vascular leakage but has no effect on sneezing, rhinorrhea, or tryptase release. Nasal blockage occurs predominantly via newly formed lipid mediators and kinins, whereas sneezing and rhinorrhea occur predominantly via preformed mediators. We propose that local hyperthermia inhibits newly formed mediator production or release or reduces the sensitivity of the vasculature to inflammatory mediators in general. Further investigation into the mechanisms and potential uses of local hyperthermia is warranted.

The protective effect of inhaled leukotriene D4 receptor antagonist ICI 204,219 against exercise-induced asthma

Leukotrienes are potent bronchoconstrictors, and they are present in the airways of asthmatic subjects. Leukotriene receptor antagonists given intravenously or orally prior to exercise attenuate the bronchoconstrictor response to exercise in asthma. We have determined the prophylactic effect of an inhaled leukotriene D4-receptor antagonist ICI 204,219 (400 micrograms) against exercise-induced bronchoconstriction in nine asthmatic subjects in a randomized, placebo-controlled, double-blind, cross-over study. Exercise challenge was performed on a cycle ergometer at a predetermined work load that was kept constant throughout the study. A "screening" and a "run-in" exercise test were performed to determine the reproducibility of the challenge. ICI 204,219 or matched placebo was given 30 min prior to exercise challenge, and bronchoconstriction after exercise was assessed as change in FEV1 over 30 min. There was no significant effect on baseline airway caliber at 20 min after inhalation of ICI 204,219. ICI 204,219 significantly inhibited the bronchoconstrictor response to exercise. The mean maximal percentage fall in FEV1 after exercise was 14.5% as compared with the placebo of 30.2% (p = 0.043), and the area under curve (AUC) for FEV1 during the first 30 min (AUC0-30) after exercise was significantly reduced (p = 0.043). The time for recovery of FEV1 to 5% of baseline was also significantly shorter with ICI 204,219 than with placebo (median, 20 versus 60 min; p = 0.018). The protection against exercise-induced bronchoconstriction provided by ICI 204,219 was variable, with almost complete inhibition of the response in three subjects, partial inhibition in another three subjects, and no protection in three subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative nasal effects of bradykinin and histamine: influence on nasal airways resistance and plasma protein exudation

BACKGROUND

Bradykinin may contribute to the pathogenesis of allergic rhinitis. Like histamine, nasal challenge with bradykinin induces rhinorrhoea, nasal blockage, and plasma protein leakage. Their comparative nasal potencies have not, however, been fully elucidated.

METHODS

Three double blind, randomised, placebo controlled and cross-over studies were undertaken to compare objectively the nasal effects of bradykinin, histamine, and vehicle.

RESULTS

Both bradykinin and histamine produced dose dependent increases in nasal airways resistance (NAR). There was no significant difference in the effects of bradykinin and histamine on NAR at any dose level. On a molar basis, however, bradykinin was 6.98 times more potent than histamine in inducing a 50% increase in NAR. Nasal challenge with bradykinin and histamine also induced significant rhinorrhoea compared with vehicle. The amount of rhinorrhoea induced by histamine was significantly greater than that induced by bradykinin at any dose level. Bradykinin and histamine induced dose dependent nasal pain and nasal itch respectively. When administered as single doses both bradykinin (1.9 mumol) and histamine (1.9 mumol) induced significant rhinorrhoea compared with the vehicle. The volume of rhinorrhoea secretions induced by histamine was 29% greater than that induced by bradykinin. In contrast, although NAR was increased significantly more by histamine than by the vehicle, the effect of bradykinin on NAR was significantly greater than histamine and vehicle in both magnitude and duration of effect. The incremental effect of bradykinin on lavage albumin levels was also significantly greater than both histamine and vehicle.

CONCLUSIONS

This study shows that the nasal vascular effects of histamine are less prominent than its actions on rhinorrhoea, and that the greater obstructive effect of bradykinin than histamine on NAR may contribute to the relative lack of efficacy of H1 antihistamines on nasal blockage in clinical disease.

The influence of terfenadine and ipratropium bromide alone and in combination on bradykinin-induced nasal symptoms and plasma protein leakage

Nasal instillation of bradykinin elicits many of the characteristic features of rhinitis. To assess the relevance of histamine release from metachromatic cells and the activation of cholinergic pathways, we investigated the effects of terfenadine, a histamine H1-receptor antagonist, and ipratroprium bromide, a selective antimuscarinic agent, on bradykinin induced rhinorrhoea, nasal airways resistance (NAR), nasal pain and plasma protein leakage. Oral terfenadine (120 mg) or matched placebo and nasal ipratropium bromide (80 micrograms) or matched placebo were administered at 4 hr and 30 min respectively prior to bradykinin nasal challenge in two randomized, double-blind and cross-over studies on eight non-rhinitic subjects. Thus subjects received either double-placebo, oral terfenadine and nasal placebo, oral placebo and nasal ipratopium bromide or oral terfenadine and nasal ipratropium bromide, as pretreatment. Bradykinin challenge induced mean maximal increases of 57%, 59%, 77% and 72% in NAR on the placebo, terfenadine, ipratropium bromide and terfenadine plus ipratropium bromide pretreatment days respectively. These increments were not significantly different. Similarly rhinorrhoea and nasal pain induced by bradykinin nasal challenge were not significantly different on the four challenge days. Bradykinin nasal challenge caused a mean maximal increase in albumin levels in recovered nasal lavages of 11.5, 13.0, 12.2 and 12.3 times of baseline levels on the placebo, terfenadine, ipratropium bromide and terfenadine plus ipratroprium bromide pretreatment days respectively. Similarly total protein levels achieved a mean maximal increase of 8.0, 8.2, 7.9 and 8.8 times of baseline levels on these challenge days. The increments in both albumin and total protein did not significantly differ on the 4 challenge days.(ABSTRACT TRUNCATED AT 250 WORDS)

Nasal effects of bradykinin and capsaicin: influence on plasma protein leakage and role of sensory neurons

Nasal insufflation with bradykinin induces nasal discomfort, rhinorrhea, and nasal blockage, all features of rhinitis. We recently showed these effects to be mediated by the B2-receptor subtype, which has been identified at neural and vascular sites. To investigate the relative contribution of capsaicin-sensitive sensory neural stimulation to the action(s) of bradykinin, two randomized double-blind placebo-controlled studies have been undertaken comparing the nasal effects of single-dose administrations of bradykinin (1.88 x 10(-3) M) and capsaicin (3.28 x 10(-5) M). In comparison with placebo, both bradykinin and capsaicin induced nasal pain/discomfort (P less than 0.01) and rhinorrhea (P less than 0.02). Bradykinin significantly increased nasal airways resistance (P less than 0.005) and plasma protein exudation (P less than 0.02). No such changes were identified after nasal challenge with capsaicin. These findings suggest that bradykinin-induced nasal discomfort and rhinorrhea are neurally mediated, whereas the effects on nasal airways resistance and plasma protein exudation are due to a direct vascular action. In addition, these findings question the role of capsaicin-sensitive sensory neurons in nasal vasculature responses, because no vascular effects of capsaicin could be identified in the human nasal mucosa.

Fine structure of the human corpus cavernosum

This paper demonstrates the ultrastructure of the human corpus cavernosum from eight male transexuals (aged 20 to 30 years) undergoing penectomy. The presence of collagen, smooth muscle, endothelial cells lining cavernous spaces, mast cells, and different types of nerve terminals, including those of a nonadrenergic and noncholinergic type, are illustrated.

Inhibition of adenosine 5'-monophosphate- and methacholine-induced bronchoconstriction in asthma by inhaled frusemide

Recent studies have shown that inhaled frusemide exerts a protective effect against various bronchoconstrictor stimuli in asthma including exercise, fog and allergen. Since mast cell activation seems to be a component of bronchoconstriction by these stimuli it is possible that inhibition of mediator release accounts for some or all of the inhibitory effects of frusemide in asthma. Since inhaled adenosine 5'-monophosphate (AMP) is another stimulus that produces bronchoconstriction by augmenting mast cell mediator release, we have investigated the ability of this drug to antagonise the airway effects of inhaled AMP and methacholine in a randomized, placebo-controlled, double-blind study of 12 asthmatic subjects. Inhaled frusemide (approximately 28 mg) administered 5 min prior to challenge increased the provocation concentration of inhaled AMP and methacholine required to reduce forced expiratory volume in one second (FEV) by 20% from baseline from 30 to 96 mg.ml-1 (p less than 0.01) and from 1.1 to 1.8 mg.ml-1 (p less than 0.01), respectively. The protection that frusemide afforded against AMP was significantly greater than that against methacholine (p less than 0.05). These data suggest that inhaled frusemide may serve as a functional antagonist against a smooth muscle spasmogen, such as methacholine, possibly by augmenting prostanoid generation. Its more potent activity against AMP and other bronchoconstrictor stimuli, that are considered to involve mast cell mediators, suggests an additional action on mast cell functions possibly at the level of the Ca++/Mg(++)-ATPase.

Inhibition of adenosine 5'-monophosphate- and methacholine-induced bronchoconstriction in asthma by inhaled frusemide

Recent studies have shown that inhaled frusemide exerts a protective effect against various bronchoconstrictor stimuli in asthma including exercise, fog and allergen. Since mast cell activation seems to be a component of bronchoconstriction by these stimuli it is possible that inhibition of mediator release accounts for some or all of the inhibitory effects of frusemide in asthma. Since inhaled adenosine 5'-monophosphate (AMP) is another stimulus that produces bronchoconstriction by augmenting mast cell mediator release, we have investigated the ability of this drug to antagonise the airway effects of inhaled AMP and methacholine in a randomized, placebo-controlled, double-blind study of 12 asthmatic subjects. Inhaled frusemide (approximately 28 mg) administered 5 min prior to challenge increased the provocation concentration of inhaled AMP and methacholine required to reduce forced expiratory volume in one second (FEV) by 20% from baseline from 30 to 96 mg.ml-1 (p less than 0.01) and from 1.1 to 1.8 mg.ml-1 (p less than 0.01), respectively. The protection that frusemide afforded against AMP was significantly greater than that against methacholine (p less than 0.05). These data suggest that inhaled frusemide may serve as a functional antagonist against a smooth muscle spasmogen, such as methacholine, possibly by augmenting prostanoid generation. Its more potent activity against AMP and other bronchoconstrictor stimuli, that are considered to involve mast cell mediators, suggests an additional action on mast cell functions possibly at the level of the Ca++/Mg(++)-ATPase.

Biological activity and anti-prostaglandin effects of prostaglandin analogue, ent-11-epi-15-epi PGE2 methyl ester

The biological activity and anti-prostaglandin property of the prostaglandin analogue, ent-11-epi-15-epi PGE2 methyl ester, were studied on isolated guinea pig ileum. Ent-11-epi-15-epi PGE2 methyl ester contracted guinea pig ileum and produced a concentration-response curve parallel to that of PGE2. However, the former exhibited a lower maximal effect than PGE2. At concentrations greater than 10(-6)M, ent-11-epi-15-epi PGE2 methyl ester selectively antagonized contractile actions of PGE2 and PGE2 alpha without affecting contractions induced by acetylcholine. These observations suggest that the PG analogue acted like a competitive antagonist to PGE2 and PGF2 alpha on guinea pig ileum in vitro.

Effect of histamine on human vas deferens in vitro

Histamine, 2-methylhistamine and 4-methylhistamine produced concentration-related contractions in some isolated human vas deferens preparations. The contractions produced by histamine and its analogues were reversibly and competitively antagonised by the H1-receptor blocker, mepyramine, but not the H2-receptor blockers, burimamide and cimetidine. Phentolamine, atropine and guanethidine did not affect the excitatory action of histamine. Histamine and 4-methylhistamine did not show any inhibitory effect on KCl-induced tone. The results showed that histamine receptors were present in the human vas deferens and the histamine receptors mediating the excitatory response were likely to be H1-receptors.

Relationship between the pharmacokinetics and the analgesic and respiratory pharmacodynamics of epidural sufentanil

To establish the relationships between epidural sufentanil analgesia and respiratory effects and to determine the pharmacokinetics of the drug, 22 adult patients undergoing thoracotomy were put into a randomized, double-blind study and received either 30, 50, or 75 micrograms per dose in 20 ml normal saline solution. Repeated doses were given on request for the 24-hour study period. There was a weak but significant nonlinear correlation between length of effective analgesia and the cumulative dose of the drug (r = 0.26, p less than 0.001). In 12 of 22 patients, the maximal length of effective analgesia was reached before the last dose and the effect tended to taper off thereafter. The mean maximal length of effective analgesia was 4.69 +/- 0.32 hours (mean +/- SEM), whereas the length of effective analgesia with the last dose was only 3.34 +/- 0.46 hours (p less than 0.0005). There was a significant correlation between the peak serum concentrations of sufentanil during the dose interval and the length of effective analgesia (r = 0.44, p less than 0.0001). Area under the concentration-time curve was proportional to the size of the epidural dose, and with all three doses tested there was a gradual accumulation of sufentanil in the serum. Mean time-to-peak concentration (tmax) increased with repeated doses (p less than 0.05). Mean serum concentration of sufentanil during periods of slow respiratory rate (0.47 +/- 0.05 ng/ml) was significantly higher than during episodes without adverse respiratory effects (0.37 +/- 0.05 ng/ml, p less than 0.05). The above data suggest that an important part of the analgesic and adverse effects of sufentanil are mediated centrally, after this opioid is absorbed systemically.

Possible involvement of receptors in the entry of Kunjin virus into Vero cells

The results obtained from electron microscopy, adsorbed and internalised virus assays and immunofluorescence studies supported that the most likely mode of entry of Kunjin virus into Vero cells was by receptor-mediated endocytosis. This was deduced indirectly from the time sequence of events that occurred. Electron microscopy revealed that endocytosis of the virus through coated vesicles had occurred. The adsorbed and internalised virus assay and immunofluorescence studies showed that there were two factors being recycled during endocytosis: the receptor for the virus and clathrin, the protein found on coated pits and vesicles. The study showed that clathrin was recycled first, followed by the receptor.

Analgesic and respiratory effects of epidural sufentanil in patients following thoracotomy

Immediately following thoracotomy, 22 patients were entered into a randomized, double blind study comparing the effects of three lumbar epidural doses of sufentanil on postoperative pain and respiratory pattern. Patients were given either 30 micrograms (group I), 50 micrograms (group II), or 75 micrograms (group III) of epidural sufentanil in 20 ml N saline. Repeat doses were given on request for the 24-h study period. Linear analogue pain score (PS), heart rate (HR), and mean arterial pressure (MAP) were measured at 15-min intervals after each dose. Respiratory depression was assessed by the presence of: 1) slow respiratory rate (SRR--less than 10 breaths per minute for greater than 5 min), 2) apnea (AP--cessation of tidal ventilation for greater than 15 s), and 3) increased PaCO2 in arterial blood gases (ABG) drawn at regular intervals. SRR and AP were measured using respiratory inductive plethysmography (RIP). A further group of ten patients (group IV) underwent preoperative RIP monitoring during sleep and in the absence of any drug. Maximum analgesia was achieved within 15 min after a dose of sufentanil for all groups. Analgesia was not significantly prolonged by increasing the dose of sufentanil. SRR occurred in all four groups (group I: 2/9; group II: 2/6; group III: 7/7; group IV: 2/10 P less than 0.05 I, IV:II, I, IV:III, II:III). The number of episodes of SRR/hr was highest in group II (group I: 0.6 +/- 0.8, group II: 4.12 +/- 0.6, group III: 1.8 +/- 2.0, group IV: 0.5 +/- 0.2) (NS).(ABSTRACT TRUNCATED AT 250 WORDS)

A comparison of some pharmacological actions of prostaglandin E1, 6-oxo-PGE1 and PGI2

Some pharmacological actions of prostaglandin E1 (PGE1), 6-oxo-PGE1 and PGI2 have been studied. 6-oxo-PGE1 and PGE1 relaxed guinea-pig tracheal muscle in vitro and increased nasal patency in normal volunteers and in subjects with vasomotor rhinitis whereas PGI2 produced opposite effects. All three compounds produced bronchodilatation in the anaesthetised guinea-pig and relaxed human respiratory tract muscle in vitro. PGI2 was several times more potent than either 6-oxo-PGE1 or PGE1 against ADP-induced aggregation of human and baboon platelets in vitro. Intravenous 6-oxo-PGE1 in the baboon caused an ex vivo inhibition of platelet aggregation, but the EC50 was 7.7 times that of PGI2. As a vasodepressor in the baboon 6-oxo-PGE1 and PGI2 were equipotent. Thus with the exception of the vasodepressor effect, the actions of 6-oxo-PGE1 qualitatively and quantitatively resembled those of the structurally related PGE1 rather than those of PGI2.

Inhibition of platelet aggregation and antagonism of vasopressin-induced ECG changes in primates by a carboprostacyclin analogue, ZK 36374

A chemically stable carboprostacyclin analogue, ZK 36374 has been compared with two other prostacyclin derivatives with respect to ADP-induced in vitro aggregation of baboon and human platelets and ex vivo platelet aggregation in the baboon. ZK 36374 was also tested on the systemic arterial blood pressure of the baboon and against vasopressin-induced ECG changes in primates. Compared to the other two compounds, ZK 36374 displayed enhanced anti-platelet aggregating activity; there was dissociation between this property and its hypotensive potency. ZK 36374 antagonized the vasopressin-induced ECG changes. These results indicate that ZK 36374 possesses therapeutic potential in vascular disease including that affecting the coronary vessels.

Inhibition of platelet aggregation with intravenous and oral administration of a carboprostacyclin analogue, 15-cyclopentyl-omega-pentanor-5(E)-carbacyclin (ONO 41483) in man

Intravenous and oral administration of a chemically stable carboprostacyclin analogue, 15-cyclopentyl-omega-pentanor-5(E)-carbacyclin (ONO 41483), resulted in ex-vivo inhibition of ADP-induced platelet aggregation in man. The maximum tolerated intravenous dose was 2.5 ng/kg/min for 1 hour and this produced a mean of 27.1% inhibition in 3 volunteers. For oral administration the tolerated single dose was 200 microgram. At this dose, there was 56.3% inhibition of aggregation (mean of 3 results). High oral (400 microgram) and intravenous doses (5 and 10 ng/kg/min for 1 hour) of ONO 41483, which caused marked inhibition of aggregation (ranging 39-100%), was accompanied by flushing of face and extremities, headache and phlebitis. However, none of the doses tested produced significant changes in arterial blood pressure or heart rate.

Inhibition of platelet aggregation and reversal of vasopressin-induced ECG changes by a carboprostacyclin analogue, ONO 41483, in primates

15-cyclopentyl-omega-pentanor-5(E)-carbacyclin (ONO 41483), a chemically stable carboprostacyclin analogue, was 3.3 times less active than prostacyclin but was 2.6 times more active than carboprostacyclin in inhibiting aggregation of ADP-induced baboon platelet in vitro. On human platelets in vitro, ONO 41483 was 9.4 times less active than prostacyclin and 12.7 times more active than carboprostacyclin. ONO 41483 was 3.7 times less active than prostacyclin but was 2.2 times more active than carboprostacyclin in producing a fall in arterial blood pressure in anaesthetised baboons. Intravenous and oral administration of ONO 41483 in baboons produced ex vivo inhibition of ADP-induced platelet aggregation at doses that did not affect blood pressure or heart rate. In addition, bolus intravenous doses (3 to 10 micrograms/kg) of ONO 41483 reversed vasopressin-induced ECG changes in the monkey, suggesting an ability of the compound to relieve coronary spasm.