Pharmacological implications of lengthened in-utero exposure to nevirapine

Given as a single dose to the mother during labour, nevirapine can protect the neonate from HIV-1 infection for up to 7 days. However, after maternal nevirapine therapy during pregnancy, neonatal plasma concentrations of nevirapine decline more rapidly, suggesting in-utero liver enzyme induction.

Pharmacokinetics and tolerability of gemifloxacin (SB-265805) after administration of single oral doses to healthy volunteers

Gemifloxacin (known as SB-265805 or LB-20304) is a potent, novel fluoroquinolone compound with a broad spectrum of antibacterial activity. The pharmacokinetics and tolerability of oral gemifloxacin were characterized in healthy male volunteers after a single dose of 20, 40, 80, 160, 320, 600, or 800 mg. Multiple serum and urine samples were collected and analyzed for gemifloxacin using high-performance liquid chromatography with fluorescence detection. Safety assessments included vital signs, 12-lead electrocardiogram readings, hematology, clinical chemistry, urinalysis, and adverse-experience monitoring. Gemifloxacin was rapidly absorbed after all doses. Maximum concentrations of gemifloxacin in serum (C(max)) were achieved approximately 1 h after dosing, after which concentrations in serum declined in a biexponential manner. Values of C(max) and the area under the concentration-time curve in serum from 0 h to infinity (serum AUC(0-infinity)) increased linearly with dose. Serum AUC(0-infinity) values (mean +/- standard deviation) were 0.65+/-0.01, 1.28+/-0.22, 2.54+/-0.31, 5.48+/-1.24, 9.82+/-2.70, 24.4+/-7.1, and 31.4+/-7.6 microg. h/ml following 20-, 40-, 80-, 160-, 320-, 600-, and 800-mg doses, respectively. The terminal phase elimination half-life was independent of dose, with an overall mean of 7.4+/-2.0 h. The profiles indicated that the pharmacokinetic profile is suitable for a once-daily dosing regimen. Approximately 25 to 40% of the administered dose was excreted unchanged in the urine, and renal clearance (ca. 150 ml/min) was independent of dose. There were no significant changes in clinical chemistry, hematology, or urinalysis parameters, vital signs, or 12-lead electrocardiogram readings in subjects, irrespective of dose. The results of these studies support the further investigation of once-daily administration of gemifloxacin.

Creating an adult learning culture through practice development

The development of a learning culture is becoming a dominant theme in the strategic plans of health care organisations. This is arising through a drive to improve standards of practice, bridge the perceived theory-practice gap and create means of integrating learning with practice. There have been many initiatives to create such a change, including continuous professional development, reflective practice, clinical supervision and work based learning. This paper presents an account of a practice development strategy that aimed to create a learning culture as a sub-element of the overall programme of work. Working with individual project leaders, the intention was to shift the emphasis away from classroom based education, to learning at and from work. This was achieved through a combination of action research, the application of adult learning theory and facilitation. The paper describes the context of the development strategy, the facilitation processes adopted including the theoretical underpinnings and some 'tentative' outcomes achieved.

Effect of oral sodium loading on high-intensity arm ergometry in college wrestlers

PURPOSE

The aim of this study was to examine the effect of 0.3 g x kg(-1) of NaHCO3, 0.21 g x kg(-1) of NaCl, and a low-calorie placebo control (PC) on high-intensity arm ergometry in eight college wrestlers (aged 20.6 +/- 0.8 yr, body mass 70.4 +/- 2.1 kg).

METHODS

Subjects performed eight 15-s intervals of maximal effort arm ergometry separated by 20 s of recovery cranking. Treatments were administered in a randomized, double-blind manner in two equal doses at 90 and 60 min before testing. Venous blood samples were withdrawn at baseline, preexercise, and postexercise intervals.

RESULTS

Preexercise pH (7.33 +/- 0.01, 7.31 +/- 0.01, and 7.40 +/- 0.01) and base excess (2.41 +/- 0.35, 0.93 +/- 0.39, and 8.45 +/- 0.51) after PC and NaCl ingestion, respectively, were similar, whereas ingestion of NaHCO3 resulted in significantly higher values (P < or = 0.05). Postexercise pH (7.02 +/- 0.01, 7.02 +/- 0.03, and 7.09 +/- 0.03) and base excess (-13.29 +/- 0.96, -14.49 +/- 1.01, and -8.83 +/- 1.38) were significantly lower after both PC and NaCl ingestion compared with NaHCO3 ingestion. Postexercise plasma [lactate] was also greater in both PC and NaHCO3 trials (21.42 +/- 1.52, 20.07 +/- 1.39, and 22.65 +/- 1.77 mmol x L(-1)). However, peak power (370.7 +/- 26.0, 346.3 +/- 13.6, and 354.3 +/- 18.9 W) and total work accomplished in eight intervals (30.2 +/- 1.5, 29.6 +/- 1.1, and 29.9 +/- 1.1 kJ), and percent fatigue (31.0 +/- 2.7, 29.0 +/- 3.2, and 29.2 +/- 4.0%) were similar.

CONCLUSIONS

These data contradict previous reports of ergogenic benefits NaHCO3 and NaCl administration before exercise and further suggest that performance in this type of activity may not be enhanced by exogenously induced metabolic alkalosis or sodium ingestion.

Induction of human neutrophil apoptosis by nitric oxide donors: evidence for a caspase-dependent, cyclic-GMP-independent, mechanism

This study investigated the regulatory effects of the major inflammatory mediator, nitric oxide (NO), on human neutrophil apoptosis in vitro. Co-culture of human neutrophils with the NO donors GEA 3162 (1,2,3,4-oxatriazolium,5-amino-3-(3,4-dichlorophenyl)-chloride) (10-100 microM) and 3-morpholino-sydnonimine (SIN-1) (0.3-3 mM) caused a dramatic and concentration-dependent induction of apoptosis. However, N-formyl-methionyl-leucyl-phenylalanine (FMLP)-induced neutrophil activation (actin reorganization and chemotaxis) was inhibited by GEA 3162 treatment. The pro-apoptotic effects of the NO donors were (i) unaffected by the soluble guanylate cyclase inhibitor LY-83583 (6-anilino-5,8-quinolinedione; 100 microM), (ii) antagonized by superoxide dismutase (6 microg/mL), (iii) mimicked by exogenous peroxynitrite (at concentrations >100 microM), and (iv) inhibited by the caspase inhibitor Z-Val-Ala-DL-Asp-fluoromethylketone (100 microM). The pro-apoptotic effect of the NO donors was not mimicked by the cell-permeable cyclic nucleotide analogue, N6,2-O-dibutyrylguanosine-3',5'-cyclic monophosphate (dibutyryl-cGMP) at concentrations < or =0.2 mM. Indeed, at high concentrations (> or =2 mM), dibutyryl-cGMP caused an inhibition of apoptosis. These results suggest that NO-mediated apoptosis, although caspase-dependent, is mediated by a cGMP-independent mechanism and involves the concurrent generation of oxygen free radicals and, potentially, peroxynitrite. Our data reveal a unique role for NO in inflammatory responses with differential effects upon neutrophil activation and survival, with important implications for the successful resolution of inflammation.

Bronchoalveolar lavage fluid urea as a measure of pulmonary permeability in healthy smokers

The effects of cigarette smoking on blood to airway pulmonary permeability to the low-molecular-weight solute urea were investigated, in an attempt to evaluate its use as a dilution marker for bronchoalveolar lavage (BAL) studies. Five healthy normal smokers who smoked a cigarette 10 min prior to undergoing a 3 x 60 mL bronchoalveolar lavage (BAL), and five nonsmokers who also underwent BAL but without cigarette smoke exposure were studied. Five minutes before bronchoscopy, 4 MBq 3H-water and 1 MBq 14C-urea were injected intravenously and biochemical urea assays and an indirect radiotracer method were used to evaluate permeability. It was shown that the smoking group had less urea in their BAL supernatants compared to nonsmokers the results using the radiotracer method being significant (p<0.005). Using both methods, it was shown that levels of urea increased in sequentially aspirated aliquots in both groups. The median directly assayed levels of urea in the smokers rose as follows: aliquot 1 0.05 micromol x mL(-1), (range 0.03-0.14), aliquot 2 0.10 micromol x mL(-1) (0.07-0.17), aliquot 3 0.12 micromol x mL(-1) (0.06-0.23) (p<0.05). This led to significantly increased calculated levels of epithelial lining fluid in the sequential aliquots (p<0.05). In addition, there were large but variable amounts of labelled water detected in both subject groups indicating a complex interaction between the BAL procedure and the circulation. Changing urea measurements during the bronchoalveolar lavage procedure confound the use of the urea (epithelial lining fluid) method for normalizing dilution factors. The use of epithelial lining fluid determinations in smokers ignores the additional and probably complex permeability changes. The present data suggest that acute exposure to cigarette smoke in smokers may decrease blood to airway permeability.

Referrals to the Marie Curie nursing service in North Yorkshire

District and Marie Curie nurses participated in a small-scale study to describe referrals to a Marie Curie service in one English health district over a 3-month period. The number of new patients referred was small; they were geographically clustered and had widely differing life expectancies. Anecdotal reports of difficulties with the 'Nurselink' referral system were not confirmed, and in situations where the system was in operation, Marie Curie nurses were more likely to speak directly to the referring nurse. The most frequently cited reason for referral was general nursing needs; however, Marie Curie nurses felt that they were most often involved to provide family support. These findings suggest that there may not be a shared understanding of the Marie Curie nurse's role, and that equity in community palliative nursing care merits examination. Defining and publicizing the role of the Marie Curie nurse, providing guidance for referrals and prioritizing communication between professionals are proposed not only to enhance the service locally but to ensure that the service is available to all. This article illustrates the value of research to identify ways to improve service delivery.

Airway neutrophilia in stable and bronchiolitis obliterans syndrome patients following lung transplantation

BACKGROUND

The bronchiolitis obliterans syndrome (BOS) remains the major constraint on the long term success of lung transplantation. Neutrophils have been associated with fibrosing lung conditions and have been noted to be increased in the bronchoalveolar lavage (BAL) fluid of patients with BOS.

METHODS

This study was undertaken to examine neutrophil accumulation in the BAL fluid, airway wall and lung parenchyma, as well as levels of interleukin (IL)-8 in the BAL fluid, in normal controls and lung transplant recipients with and without BOS. Bronchoscopic examination included endobronchial biopsy (EBB), BAL fluid, and transbronchial biopsy (TBB) sampling. Tissue neutrophils were identified by neutrophil elastase staining on 3 microm paraffin biopsy sections and quantified by computerised image analyser. IL-8 levels were measured in unconcentrated BAL fluid by ELISA.

RESULTS

Compared with controls, airway wall neutrophilia was increased in both stable lung transplant recipients and those with BOS (p<0.05). BAL neutrophils and IL-8 levels were also increased in both groups of transplant recipients compared with controls (p<0.01), the levels being significantly higher in the BOS group (p<0.01). Neutrophil numbers in the lung parenchyma were not significantly different between the two groups of lung transplant recipients.

CONCLUSION

Increased levels of neutrophils are present in the airway wall and BAL fluid of lung transplant recipients with and without BOS. BAL fluid levels of IL-8 are also increased, raising the possibility that neutrophils and/or IL-8 may play a part in the pathogenesis of BOS following lung transplantation.

Pharmacological manipulation of granulocyte apoptosis: potential therapeutic targets

Resolution of inflammation involves the clearance of excess or effete inflammatory cells by a process of physiological programmed cell death (apoptosis) and the subsequent recognition and removal of apoptotic cells by phagocytes. The therapeutic induction of apoptosis for the resolution of chronic inflammation and the general pharmacology of apoptosis have become subjects of increasing interest. In this article, some of the unique and important differences in the control of apoptosis of various inflammatory cells (particularly neutrophil and eosinophil granulocytes) are highlighted. It is suggested that apoptosis can be specifically regulated pharmacologically and could be exploited to develop new drug therapies.

In stable lung transplant recipients, exhaled nitric oxide levels positively correlate with airway neutrophilia and bronchial epithelial iNOS

In conditions characterized by airway inflammation, exhaled nitric oxide (eNO) levels are increased. Variable degrees of airway inflammation are present in stable lung transplant recipients (LTR), and may lead to airway remodeling and chronic graft dysfunction. The hypothesis tested is that in stable LTR, eNO concentrations would reflect the expression of inducible (iNOS) (but not constitutive [cNOS] nitric oxide synthase) in the bronchial epithelium as well as the degree of airway inflammation. We determined eNO concentrations in 20 stable LTR, free of infection, rejection, or obliterative bronchiolitis (OB). At routine bronchoscopy, we measured the differential cell count on bronchoalveolar lavage (BAL) and a quantitative assessment of iNOS and cNOS expression in endobronchial biopsies by immunohistochemistry. Mean +/- SEM eNO concentrations in stable LTR were not significantly different from control subjects (13 +/- 0.7 ppb versus 14.2 +/- 0.49; p = 0.42). Percent BAL neutrophils was 11.5 +/- 3.2 which was significantly higher than in a group of local control subjects (1.7 +/- 0.6; p < 0.001). The bronchial epithelium and lamina propria contained abundant iNOS but cNOS was present only in the lamina propria. Using regression analysis, percent BAL neutrophils (r(2) = 0.82; p < 0.0001) and iNOS expression in the bronchial epithelium (r(2) = 0.75; p < 0.0001), but not in the lamina propria (r(2) = 0.16; p = 0.08), were positively predictive of eNO. There was an inverse relationship between cNOS and eNO. We conclude that eNO concentrations although normal for the group, still reflect the degree of airway inflammation in stable LTR. Epithelial iNOS appears to be the major source of eNO and expression of cNOS may be downregulated with increasing iNOS expression.

An antiinflammatory effect of salmeterol, a long-acting beta(2) agonist, assessed in airway biopsies and bronchoalveolar lavage in asthma

The addition of long-acting beta(2) agonists to inhaled corticosteroid (ICS) therapy in symptomatic patients with asthma improves clinical status more than increasing the dose of ICS. It has been suggested that these benefits could be at the cost of an increase in airway inflammation, but few histopathological studies have been performed in the relevant group. In a double-blind, parallel-group, placebo-controlled study, we randomly assigned 50 symptomatic patients with asthma who were receiving ICS (range, 100 -500 microgram/d) to 12 wk of supplementary treatment with salmeterol (50 microgram twice daily) or fluticasone (100 microgram twice daily) or placebo. Bronchial biopsies and BAL were obtained from 45 patients before and after treatment and analyzed. After treatment with salmeterol there was no deterioration of airway inflammation as assessed by mast cells, lymphocytes, or macrophages in BAL or biopsies, but rather a significant fall in EG1-positive eosinophils in the lamina propria (from a median 18.3 to 7.6 cells/mm, p = 0.01), which was not seen after treatment with fluticasone. The only cellular effect of added fluticasone was a decrease in BAL lymphocyte activation. There was a concurrent improvement in clinical status, more marked with salmeterol than with increased ICS. Thus, adding salmeterol to ICS is not associated with increased "allergic" airway inflammation, but conversely with a complementary antieosinophil effect.

Psychotropic drug utilization in long-term-care facilities for the elderly in Ontario, Canada

OBJECTIVE

Despite considerable data from a number of countries regarding psychotropic utilization in long-term-care facilities for the elderly, there has been a lack of similar data from Canada. The purpose of this study was to gather prescription data from a series of institutions in Ontario and to compare the results to those of other international studies.

METHOD

Single-day surveys were carried out in six homes for the aged, four nursing, homes, two retirement homes, and a veterans' center. The results were compared to those of recent studies from other countries.

RESULTS

The data revealed considerable differences in rates of prescription between different classes of institutions and between similarly classified institutions. The prescription rate of neuroleptics ranged from 11.8% (of patients) in retirement homes to 29.8% in nursing homes. Antidepressant use ranged from 12.2% in nursing homes to 24.6% in homes for the aged, and benzodiazepine use ranged from 22.5% in nursing homes to 36.4% in retirement homes.

CONCLUSIONS

The overall rate of prescription for psychotropic medications was somewhat lower than in most international studies. The rate of prescription of neuroleptics in nursing homes fell in the midrange of studies, somewhat higher than in recent studies from the United States and an earlier Italian study, but lower than in recent reports from Sweden, Austria, and Australia. The rate of neuroleptic use in homes for the aged was comparable to the rate in the U.S. studies. The overall rate of prescription of antidepressants and benzodiazepines appears to be comparable to that in recent studies from other countries.

Role of neutrophil apoptosis in the resolution of pulmonary inflammation

Neutrophil-mediated lung injury may result from one or more of the following possible causes: 1) loss of the normal mechanisms that regulate and switch off neutrophil influx, 2) inappropriate or uncontrolled neutrophil activation within the lung, 3) inhibition of neutrophil apoptosis, and 4) impairment or saturation of the normal macrophage-dependent process for the removal of apoptotic neutrophils. Current in vitro data indicate that many factors operating at the inflamed site (e.g. cytokines, growth factors, chemotactic peptides, hypoxia, acidosis, etc.) serve a dual function in both priming and activating these cells, and delay apoptosis. The observation that the rate of eosinophil apoptosis can be accelerated by corticosteroid therapy in vivo suggests a novel mode of action for this drug and indicates that targeting this process in other granulocyte-dependent inflammatory conditions may offer a novel therapeutic approach in inflammatory lung disease.

Modulatory effects of alveolar macrophages on CD4+ T-cell IL-5 responses correlate with IL-1beta, IL-6, and IL-12 production

Increasing evidence suggests that the pattern of T-cell cytokine production can be modulated by antigen presenting cell (APC)-derived factors during the cell interactions. Recently, it has been shown that alveolar macrophages (AMs) from atopic asthmatics (AA) but not atopic nonasthmatics (AN) enhance interleukin (IL)-5 production by CD4+ T-cells. The present study compared AM production of IL-1beta, IL-6, and IL-12, as well as their associated functional capacity to influence IL-5 production by allergen-specific CD4+ T-cells in 10 AA, 10 AN, and nine nonatopic control subjects (C). AMs from AA showed a relatively high production of IL-1beta and IL-6 (p<0.05) and a relatively low secretion of IL-12 compared to C, whereas AMs from AN and C behaved similarly. This study confirmed previous findings that co-culture with AMs augments IL-5 production from allergen-stimulated CD4+ T-cells only in AA and not in nonasthmatics even if they are atopic. On the other hand, stimulation with allergen alone did not enhance IL-5 production by CD4+ T-cells in either AA nor AN. AM-induced changes in CD4+ T-cell IL-5 production upon allergen stimulation significantly correlated with their ability to produce IL-1beta (r=0.59, p<0.01), IL-6 (r=0.56, p<0.01), and inversely with IL-12 (r=-64, p=0.002) in all atopic subjects, and even more closely with the ratio of IL-12/IL-1beta (r=-0.75, p<0.001) and IL-12/IL-6 production (r=-0.81, p<0.001) in these subjects. These findings suggest that the role of alveolar macrophages from atopic asthmatics in enhancing interleukin-5 production by allergen-specific CD4+ T-cells is due, at least partly, to their aberrant production of interleukin-1beta, interleukin-6, and particularly of interleukin-12.

Babies born with major disabilities: the medical-legal interface

This article explores some of the legal and medical issues that confront doctors, lawyers, ethicists, and families when faced with the problems of a baby born with one or more major disabilities. Attitudes vary widely, and these are emphasised by cultural and social aspects in different parts of the world. Although the legal issues vary, in a large number of countries there appears to be less variation than with the medical issues.

Furcation depth and interroot separation dimensions for 5 different tooth types

The purpose of this study was to document mean, standard deviation, and range of furcation depth and Interroot separation dimensions of 5 multirooted tooth types. A total of 412 extracted teeth were examined and classified as: maxillary first molar, maxillary second molar, maxillary first premolar, mandibular first molar, and mandibular second molar. The furcation depth was measured at the level of the furcation dome and 3 and 5 mm apical to the dome. Interroot separation was measured 3 and 5 mm apical to the furcation dome. Mean furcation depth at the dome was 7.48 mm buccally and 6.67 mm mesiodistally for maxillary first molars; 6.69 mm buccally and 5.94 mm mesiodistally for maxillary second molars; 3.54 mm mesiodistally for maxillary first premolars; 7.96 mm buccolingually for mandibular first molars; and 7.46 mm buccolingually for mandibular second molars. Interroot separation dimensions 3 mm apical to the dome were: 2.58 mm buccally, 4.17 mm mesially, and 4.48 mm distally for maxillary first molars; 1.92 mm buccally, 3.89 mm mesially, and 4.04 mm distally for maxillary second molars; 2.47 mm mesially and 2.58 mm distally for maxillary first premolars; 3.15 mm buccally and 2.95 mm lingually for mandibular first molars; and 2.54 mm buccally and 2.75 mm lingually for mandibular second molars.

Airway vascular changes in lung allograft recipients

BACKGROUND

In asthma there has been increasing interest in the contribution of airway microvasculature to airway wall thickness and lumenal narrowing. Post-lung transplant, the survival of the donor airway is generally dependent on mixed-venous blood flow from pulmonary artery collaterals associated with the discontinuation of the bronchial circulation. This may lead to an altered vasculature of the airways post transplant, which may contribute to airflow limitation.

METHODS

Endobronchial biopsies were taken from the lower lobe sub-carinae in 22 lung transplant recipients (LTR), 8 with Bronchiolitis Obliterans Syndrome (BOS), 14 without, and 14 controls. Seven microm frozen sections were stained for type IV collagen with a monoclonal antibody, using an indirect immunoperoxidase method. Bronchial vessels were identified by typical staining of type IV collagen in the true basement membrane supporting the endothelium. The number of vessels per mm2 of submucosa to a depth of 150 microm below the basement membrane, the percent vascularity and average vessel size were quantified using a computerised image analyser.

RESULTS

Compared to the controls, a higher percent vascularity was found in LTR both with and without BOS (p < 0.05). In the BOS group, the percent best FEV1.0 decreased exponentially, in association with increased airway vessel size (r2 = 0.67, p = 0.01).

CONCLUSIONS

These findings suggest that increased airway vascularity is a feature of the allograft airways post transplant. This may be a result of the relative hypoxia and hypercarbia in the blood supplying the airways from the pulmonary artery collaterals or of the chronic inflammatory process in the airways. These changes in vascularity could contribute to airflow limitation in BOS.

NF-kappaB activation is a critical regulator of human granulocyte apoptosis in vitro

During beneficial inflammation, potentially tissue-damaging granulocytes undergo apoptosis before being cleared by phagocytes in a non-phlogistic manner. Here we show that the rate of constitutive apoptosis in human neutrophils and eosinophils is greatly accelerated in both a rapid and concentration-dependent manner by the fungal metabolite gliotoxin, but not by its inactive analog methylthiogliotoxin. This induction of apoptosis was abolished by the caspase inhibitor zVAD-fmk, correlated with the inhibition of nuclear factor-kappa B (NF-kappaB), and was mimicked by a cell permeable inhibitory peptide of NF-kappaB, SN-50; other NF-kappaB inhibitors, curcumin and pyrrolidine dithiocarbamate; and the proteasome inhibitor, MG-132. Gliotoxin also augmented dramatically the early (2-6 h) pro-apoptotic effects of tumor necrosis factor-alpha (TNF-alpha) in neutrophils and unmasked the ability of TNF-alpha to induce eosinophil apoptosis. In neutrophils, TNF-alpha caused a gliotoxin-inhibitable activation of an inducible form of NF-kappaB, a response that may underlie the ability of TNF-alpha to delay apoptosis at later times (12-24 h) and limit its early killing effect. Furthermore, cycloheximide displayed a similar capacity to enhance TNF-alpha induced neutrophil apoptosis even at time points when cycloheximide alone had no pro-apoptotic effect, suggesting that NF-kappaB may regulate the production of protein(s) which protect neutrophils from the cytotoxic effects of TNF-alpha. These data shed light on the biochemical and molecular mechanisms regulating human granulocyte apoptosis and, in particular, indicate that the transcription factor NF-kappaB plays a crucial role in regulating the physiological cell death pathway in granulocytes.