Molecular concepts of IgE-initiated inflammation in atopic and nonatopic asthma

Atopic and nonatopic (intrinsic) asthmatics were characterized by a broadly conserved bronchial mucosal proeosinophilic cytokine network in which IL-5 appears to play a key role. Inappropriate IgE-mediated mechanisms may occur in asthma, irrespective of its atopic status, as suggested by elevated serum IgE concentrations and bronchial mucosal expression of FcepsilonRI, IL-4, IL-13, Iepsilon, and Cepsilon. In general, these observations support the concept that these subtypes of asthma, despite showing distinct clinical and biologic features, share many common immunopathologic mechanisms. The most promising future directions of research regarding intrinsic asthma concern the possible identification of novel allergens or antigens, the detailed description of local bronchial mucosal IgE production, and the understanding of a possible macrophage dysfunction. Furthermore, a role for infectious (viral?) or autoimmune processes has yet to be firmly identified in intrinsic asthma. Animal models may also help us to understand the role of IgE and atopy in asthma. Although these are largely IgE-mediated mechanisms, allergen-induced bronchial hyperresponsiveness and eosinophilic inflammation can also occur in the absence of IgE (null mutation of the Cepsilon locus), as shown in a mouse model of hypersensitivity to Aspergillus fumigatus (57). Thus, despite the absence of atopy, IgE-mediated mechanisms may operate in intrinsic asthma (Fig. 1).

Characterization of authentic recombinant pea-seed lipoxygenases with distinct properties and reaction mechanisms

The two major isoforms of lipoxygenase (LOX-2 and LOX-3) from pea (Pisum sativum L. cv. Birte) seeds have been cloned and expressed from full-length cDNAs as soluble, active, non-fusion proteins in Escherichia coli. A comparison of both isoforms purified to apparent homogeneity from E. coli and pea seeds has confirmed the authenticity of the recombinant products and established the properties of the native enzymes. Despite 86% similarity at the amino acid sequence level, the enzymes have distinct properties. They have been characterized in terms of specific activity, Fe content, optimum pH, substrate and product specificity, apparent Km and Vmax for the preferred substrate, linoleic acid, and interfacial behaviour with linoleic acid. We have used this evidence, in addition to EPR spectroscopy of the hydroperoxide-activated enzymes and estimates of kcat/Km, to propose different reaction mechanisms for linoleic acid oxidation for the two isoforms. The differences relate primarily to carbonyl production from linoleic acid for which we propose a mechanism. This implicates the release of a peroxyl radical in an aerobic hydroperoxidase reaction, as the source of the carbonyl compounds formed by dismutation of the liberated peroxyl radical.

Does a radiation dose-response relation exist concerning survival of patients who have soft-tissue sarcomas of the extremities? Radiation dose-response relation for soft-tissue sarcomas

This study analyzes a single-institution experience by evaluating the impact on survival of increasing total dose of adjunctive irradiation in patients who had extremity soft-tissue sarcoma (ESTS). A retrospective review of the tumor registry at a university medical center from January 1984 through December 1992 yielded a total of 59 surgical patients of ESTS. With follow-up ranging from 30 to 135 months (median, 65 months), the 2-, 5-, and 8-year overall and disease-free survival for all patients was 86%, 71%, 58% and 76%, 70%, 56%, respectively. Multivariate analyses using the Cox proportional hazards model revealed that total radiation dose (p = 0.02), American Joint Committee on Cancer stage (p = 0.04), and tumor size (p = 0.006) were all significant prognostic factors of overall survival; however, only tumor size was predictive of disease-free survival (p = 0.02). When the effect of tumor size and disease stage were controlled in the Cox model, a dose-response curve between increasing total radiation dose and improved overall patient survival was indicated. This study demonstrates the significance of tumor size on predicting both overall and disease-free survival in patients who have soft-tissue sarcomas of the extremity. It also suggests, however, that a radiation dose-response relation may exist for overall survival. Future investigations should consider evaluating the minimal total radiation dose needed to optimize patient survival after limb-sparing surgery.

IL-3, IL-5, granulocyte-macrophage colony-stimulating factor receptor alpha-subunit, and common beta-subunit expression by peripheral leukocytes and blood dendritic cells

BACKGROUND

IL-3, IL-5, and granulocyte-macrophage colony-stimulating factor (GM-CSF) receptors consist of cytokine-specific alpha-subunits, which associate with a shared signalling common beta-subunit (beta(c)) to form a high-affinity complex. The expression of IL-3, IL-5, and GM-CSF is upregulated in atopic inflammation, and these cytokines are thought to contribute to pathology through mechanisms that include eosinophil activation.

OBJECTIVE

We sought to examine the distribution of receptor expression between cells relevant to allergic inflammation from individual subjects and to compare atopic and nonatopic individuals.

METHODS

Peripheral blood was obtained from atopic and nonatopic volunteers. Cytokine-receptor expression was examined by flow cytometry with monoclonal antibodies specific for alpha-subunits and beta(c) in combination with phenotypic markers for eosinophils, basophils, neutrophils, dendritic cells, monocytes, and T cells.

RESULTS

Using a ligand-independent system, we confirmed the cellular distribution of IL-5Ralpha, IL-3Ralpha, and GM-CSFRalpha. IL-3Ralpha and GM-CSFRalpha were detected on high-affinity IgE receptor blood dendritic cells. Beta(c) expression was detected on basophils, eosinophils, neutrophils, and, at low levels, on monocytes and dendritic cells. There was intense staining of basophils for IL-3Ralpha relative to IL-5Ralpha, GM-CSFRalpha, and beta(c), whereas eosinophil-staining intensity was similar for IL-3Ralpha, IL-5Ralpha, GM-CSFRalpha, and beta(c). There were no significant differences between atopic and nonatopic subjects in cytokine-receptor staining.

CONCLUSION

IL-3Ralpha and GM-CSRalpha are shown on a newly defined population of Fc(epsilon)RI-high dendritic cells. The intense staining of basophils for IL-3Ralpha, relative to that of IL-5Ralpha and GM-CSFRalpha, is in contrast to eosinophils from the same subjects and may explain the higher sensitivity of basophils to IL-3 compared with IL-5 and GM-CSF. We found no evidence for downregulation of receptor expression in atopic compared with nonatopic subjects, suggesting that these receptors remain accessible as potential targets for therapeutic intervention in atopic allergic disease.

Loss: an analysis of a concept of particular interest to nursing

The term 'loss' is used frequently in the nursing literature and by nurses in the clinical setting. However, loss as a concept has not been defined comprehensively. In this paper, an attempt will be made to analyse the concept. The paper will begin with an overview of approaches to concept analysis. Subsequent sections include a literature review examining current and classic usage of the concept. General and specific definitions of loss provide a template for discussion. The paper will conclude with the identification of critical attributes for the concept which will form the basis for an exploration of explicit empirical referents.

Interstitial laser hyperthermia model development for minimally invasive therapy of breast carcinoma

BACKGROUND

This investigation describes the preclinical development of a laser fiberoptic interstitial delivery system for the thermal destruction of small breast cancers. We propose adaptation of this technology to stereotactic mammographic instrumentation currently employed for diagnostic core biopsy to thermally ablate a site of disease with maximal treatment efficacy, minimal observable superficial change, reduced patient trauma, and lowered overall treatment costs.

STUDY DESIGN

Laser hyperthermia is a clinical modality that seeks to achieve tumor destruction through controlled tissue heating. The advantage of laser-induced hyperthermia over traditionally used heat sources such as ultrasound, microwave, or radiowave radiation lies in the ability to focus heat localization to the specific tumor tissue site. Neodymium:yttrium aluminum garnet (Nd:YAG) laser light transmitted through a fiberoptic cable to a diffusing quartz tip can induce such temperature increases leading to localized tissue destruction. Because breast cancer occurs with greatest frequency in the mature woman whose breast tissue has undergone glandular involution with fatty replacement, this study concentrates on determining the resultant laser energy heat distribution within fat and fibrofatty tissue. This investigation studied the time-temperature responses of ex vivo human breast and porcine fibrofatty tissue, which led to an in vivo subcutaneous porcine model for the practical demonstration of a laser hyperthermia treatment of small volumes of porcine mammary chain tissue.

RESULTS

Spatial recordings of the resultant temperature fields through time exhibited similar, reproducible thermal profiles in both ex vivo human breast and subcutaneous porcine fat. In vivo laser-produced temperature fields in porcine subcutaneous fat were comparable to those in the ex vivo analyses, and showed a histologically, sharply defined, and controllable volume of necrosis with no injury to adjacent tissues or to overlying skin.

CONCLUSIONS

Interstitially placed, fiberoptically delivered Nd:YAG laser energy is capable of controlled tissue denaturation to a defined volume for the treatment of small breast cancers. It is hoped that this minimally invasive approach, with further investigation and refinement, may lead to the effective treatment of small, well-defined breast cancers that are commonly diagnosed through stereographic mammography and stereotactic core biopsy. The juxtaposition of such a localized treatment modality with these increasingly used diagnostic tools is of considerable promise.

Concern about aspects of body image and adjustment to early stage breast cancer

OBJECTIVE

Several authors have suggested that patients adjust more poorly to breast cancer if they are heavily invested in body image as a source of their sense of self-worth. This prospective study examined this possibility, looking at two aspects of concern about body image as predictors of several indices of adjustment over the first postoperative year.

METHODS

At diagnosis (and again a year later) 66 women with early stage breast cancer reported how much they valued a) a sense of body integrity (or intactness) and b) a good physical appearance. The day before surgery, a week afterward, and at 3-month, 6-month, and 12-month follow ups, they reported on their mood. At presurgery and at follow ups they also rated their attractiveness and sexual desirability and reported on frequency of sexual interaction. At follow-ups they also indicated how much their illness and treatment were interfering with social and recreational activities.

RESULTS

Initial investment in appearance was related to distress across the postsurgical year. In contrast, investment in appearance made women more resilient against deterioration in their perceptions of attractiveness. Concern about body integrity did not strongly predict emotional distress, but it related to adverse impact on social and recreational activities in the follow-up period, to deterioration in feelings of sexual desirability, and to feelings of alienation from the self (feeling "not like yourself anymore").

CONCLUSIONS

Body image is often thought of in terms of physical appearance, but there is also a body image pertaining to integrity, wholeness, and normal functioning. People who are greatly concerned about either aspect of their body image are vulnerable to poorer psychosocial adjustment when confronting treatment for breast cancer. The poorer adjustment takes a different form, however, depending on the nature of the patient's body-image concern.

Enhanced expression of eotaxin and CCR3 mRNA and protein in atopic asthma. Association with airway hyperresponsiveness and predominant co-localization of eotaxin mRNA to bronchial epithelial and endothelial cells

Eotaxin is a newly discovered C-C chemokine which preferentially attracts and activates eosinophil leukocytes by acting specifically on its receptor CCR3. The airway inflammation characteristic of asthma is believed to be, at least in part, the result of eosinophil-dependent tissue injury. This study was designed to determine whether there is increased expression of eotaxin and CCR3 in the bronchial mucosa of asthmatics and whether this is associated with disease severity. The major sources of eotaxin and CCR3 mRNA were determined by co-localization experiments. Bronchial mucosal biopsy samples were obtained from atopic asthmatics and normal non-atopic controls. Eotaxin and CCR3 mRNA were identified in tissue sections by in situ hybridization (ISH) using radiolabeled riboprobes and their protein product visualized by immunohistochemistry (IHC). Co-localization experiments were performed by double ISH/IHC. Eotaxin and CCR3 (mRNA and protein) were significantly elevated in atopic asthmatics compared with normal controls. In the asthmatics there was a highly significant inverse correlation between eotaxin mRNA+ cells and the histamine provocative concentration causing a 20% fall in FEV1 (PC20). Cytokeratin-positive epithelial cells and CD31+ endothelial cells were the major source of eotaxin mRNA whereas CCR3 co-localized predominantly to eosinophils. These data are consistent with the hypothesis that damage to the bronchial mucosa in asthma involves secretion of eotaxin by epithelial and endothelial cells resulting in eosinophil infiltration mediated via CCR3. Since selective (eotaxin) and non-selective C-C chemokines such as RANTES, MCP-3 and MCP-4 all stimulate eosinophils via CCR3, this receptor is potentially a prime therapeutic target in the spectrum of diseases involving eosinophil-mediated tissue damage.

Associations between IL-13 and IL-4 (mRNA and protein), vascular cell adhesion molecule-1 expression, and the infiltration of eosinophils, macrophages, and T cells in allergen-induced late-phase cutaneous reactions in atopic subjects

IL-13, like IL-4, induces up-regulation of vascular cell adhesion molecule-1 (VCAM-1) expression on human endothelial cells in vitro. This may contribute to local accumulation of alpha4beta1+ inflammatory cells, such as eosinophils, macrophages, and T cells. We tested the hypothesis that in human allergic inflammatory reactions in vivo, IL-13 and IL-4 are both involved in VCAM-1/alpha4beta1-dependent recruitment of inflammatory cells. Cryostat cutaneous sections from 13 atopic subjects taken 6, 24, and 48 h after allergen challenge were processed for immunohistochemical staining and in situ hybridization using mAbs and 35S-labeled riboprobes for IL-4 and IL-13. When compared with diluent sites, allergen provoked significant increases in the numbers of cells that were mRNA+ and protein-positive for both IL-13 and IL-4 that were clearly demonstrable at 6 h, peaked at 24 h, and declined by 48 h. Double immunohistochemical staining/in situ hybridization showed that the majority (>60%) of IL-13 mRNA+ signals were colocalized to CD3+ T cells. The numbers of mRNA+ and protein-positive cells for IL-13 significantly correlated with VCAM-1 immunoreactivity on endothelial cells and with total numbers of infiltrating EG2+ eosinophils, CD45RO+ T cells, and CD68+ macrophages, but not elastase-positive neutrophils, at the 6- and 24-h time points. At 6 h, an association was also observed between the numbers of IL-4 mRNA+ or protein product-positive cells and VCAM-1 expression, although this was not statistically significant. These findings suggest that IL-13 may play an important role in recruitment of inflammatory cells to the site of cutaneous allergic inflammatory reaction through VCAM-1/alpha4beta1-dependent mechanisms.

Associations between IL-13 and IL-4 (mRNA and protein), vascular cell adhesion molecule-1 expression, and the infiltration of eosinophils, macrophages, and T cells in allergen-induced late-phase cutaneous reactions in atopic subjects

IL-13, like IL-4, induces up-regulation of vascular cell adhesion molecule-1 (VCAM-1) expression on human endothelial cells in vitro. This may contribute to local accumulation of alpha4beta1+ inflammatory cells, such as eosinophils, macrophages, and T cells. We tested the hypothesis that in human allergic inflammatory reactions in vivo, IL-13 and IL-4 are both involved in VCAM-1/alpha4beta1-dependent recruitment of inflammatory cells. Cryostat cutaneous sections from 13 atopic subjects taken 6, 24, and 48 h after allergen challenge were processed for immunohistochemical staining and in situ hybridization using mAbs and 35S-labeled riboprobes for IL-4 and IL-13. When compared with diluent sites, allergen provoked significant increases in the numbers of cells that were mRNA+ and protein-positive for both IL-13 and IL-4 that were clearly demonstrable at 6 h, peaked at 24 h, and declined by 48 h. Double immunohistochemical staining/in situ hybridization showed that the majority (>60%) of IL-13 mRNA+ signals were colocalized to CD3+ T cells. The numbers of mRNA+ and protein-positive cells for IL-13 significantly correlated with VCAM-1 immunoreactivity on endothelial cells and with total numbers of infiltrating EG2+ eosinophils, CD45RO+ T cells, and CD68+ macrophages, but not elastase-positive neutrophils, at the 6- and 24-h time points. At 6 h, an association was also observed between the numbers of IL-4 mRNA+ or protein product-positive cells and VCAM-1 expression, although this was not statistically significant. These findings suggest that IL-13 may play an important role in recruitment of inflammatory cells to the site of cutaneous allergic inflammatory reaction through VCAM-1/alpha4beta1-dependent mechanisms.

Expression of IL-4 and IL-5 mRNA and protein product by CD4+ and CD8+ T cells, eosinophils, and mast cells in bronchial biopsies obtained from atopic and nonatopic (intrinsic) asthmatics

We recently demonstrated bronchial mucosal expression of IL-4 and IL-5 at the mRNA and protein level in both atopic and nonatopic (intrinsic) asthma. In this report, using double immunohistochemistry (IHC) and in situ hybridization (ISH), we show that 70% of IL-4 and IL-5 mRNA+ signals co-localized to CD3+ T cells, the majority (>70%) of which were CD4+, although CD8+ cells also expressed IL-4 and IL-5 mRNA. The remaining IL-4 and IL-5 mRNA signals co-localized to mast cells and eosinophils. The cellular distribution of these mRNA species did not differ between atopic and nonatopic asthmatics. In contrast, double IHC showed that IL-4 and IL-5 immunoreactivity was predominantly associated with eosinophils and mast cells, with few IL-5 or IL-4 immunoreactive CD3+ T cells detectable. However, total IL-4- or IL-5-positive cells detected by IHC were <40% of the total mRNA+ cells, raising the possibility that insufficient cytokine protein accumulated within T cells to enable detection by IHC. We conclude that: 1) in atopic and nonatopic asthma CD8+ T cells, in addition to CD4+ T cells, mast cells and eosinophils express mRNA for IL-4 and IL-5; 2) whereas IL-4 and IL-5 mRNA expression was associated mainly with T cells, immunoreactivity for the corresponding protein products was detectable predominantly in eosinophils and mast cells; and 3) this discrepancy may be partly attributable to the relative insensitivity of double IHC technique that does not allow detection of cytokine protein in T cells where, unlike eosinophils and mast cells, there is no facility for storage and concentration in granules.

Expression of IL-4 and IL-5 mRNA and protein product by CD4+ and CD8+ T cells, eosinophils, and mast cells in bronchial biopsies obtained from atopic and nonatopic (intrinsic) asthmatics

We recently demonstrated bronchial mucosal expression of IL-4 and IL-5 at the mRNA and protein level in both atopic and nonatopic (intrinsic) asthma. In this report, using double immunohistochemistry (IHC) and in situ hybridization (ISH), we show that 70% of IL-4 and IL-5 mRNA+ signals co-localized to CD3+ T cells, the majority (>70%) of which were CD4+, although CD8+ cells also expressed IL-4 and IL-5 mRNA. The remaining IL-4 and IL-5 mRNA signals co-localized to mast cells and eosinophils. The cellular distribution of these mRNA species did not differ between atopic and nonatopic asthmatics. In contrast, double IHC showed that IL-4 and IL-5 immunoreactivity was predominantly associated with eosinophils and mast cells, with few IL-5 or IL-4 immunoreactive CD3+ T cells detectable. However, total IL-4- or IL-5-positive cells detected by IHC were <40% of the total mRNA+ cells, raising the possibility that insufficient cytokine protein accumulated within T cells to enable detection by IHC. We conclude that: 1) in atopic and nonatopic asthma CD8+ T cells, in addition to CD4+ T cells, mast cells and eosinophils express mRNA for IL-4 and IL-5; 2) whereas IL-4 and IL-5 mRNA expression was associated mainly with T cells, immunoreactivity for the corresponding protein products was detectable predominantly in eosinophils and mast cells; and 3) this discrepancy may be partly attributable to the relative insensitivity of double IHC technique that does not allow detection of cytokine protein in T cells where, unlike eosinophils and mast cells, there is no facility for storage and concentration in granules.

IL-4 and IL-5 mRNA and protein in bronchial biopsies from patients with atopic and nonatopic asthma: evidence against "intrinsic" asthma being a distinct immunopathologic entity

Intrinsic (nonatopic) asthma is considered to be a distinct pathogenetic variant of asthma since, unlike extrinsic (atopic) asthma, patients with the disease are skin test-negative to common aeroallergens, and have total serum IgE concentrations within the normal range. Nevertheless, the recent demonstration of increased numbers of cells expressing the high-affinity IgE receptor in bronchial biopsies from atopic and nonatopic asthmatic subjects, together with epidemiologic evidence indicating that serum IgE concentrations relate closely to asthma prevalence regardless of atopic status, suggests that IgE-mediated mechanisms may participate in the pathogenesis of both atopic and nonatopic asthma. Furthermore both variants of the disease are associated with bronchial mucosal eosinophilic inflammation. Interleukin-4 (IL-4) is an essential cofactor for IgE synthesis, and there is strong evidence that IL-5 plays a major role in eosinophil accumulation in asthmatic inflammation. For these reasons we compared the expression of IL-4 and IL-5 mRNA and protein product using a semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) amplification, in situ hybridization, and immunohistochemistry in bronchial biopsies from symptomatic atopic and nonatopic asthmatic subjects and atopic and nonatopic controls. The results showed that as compared with controls, biopsies from both groups of asthmatic subjects had increased numbers of IL-4 and IL-5 mRNA copies relative to beta-actin mRNA as detected by RT-PCR. Similarly, in situ hybridization and immunohistochemistry demonstrated increased numbers of cells expressing IL-4 and IL-5 mRNA and protein in asthmatic subjects, irrespective of their atopic status. We conclude that individuals with either atopic or nonatopic asthma show infiltration of the bronchial mucosa with cells expressing Th2-type cytokines, providing further evidence for similarities in the immunopathogenesis of these clinically distinct forms of asthma.

Partial resolution of acute interstitial pneumonia in native lung after single lung transplantation

The case of a 49 year old man presenting with rapidly progressive interstitial lung disease is described. Radiological findings and the lung biopsy specimen were compatible with an acute interstitial pneumonia, as was the relentless clinical course culminating in hypoxic respiratory failure. After right single lung transplantation there was considerable improvement in lung function and radiographic clearing of disease in the native left lung.

Safety of fibreoptic bronchoscopy in asthmatic and control subjects and effect on asthma control over two weeks

BACKGROUND

Concerns remain about the safety of bronchoscopy in asthma and there are few data on the effect of this procedure on asthma control in the days or weeks following bronchoscopy.

METHODS

In an initial study of bronchoalveolar lavage and bronchial biopsies in asthmatic and control subjects, data on peak expiratory flow rates (PEFR) collected prospectively before and after the procedure were available from 21 of the 29 asthmatic subjects studied. These showed a median 23% fall in PEFR from baseline after bronchoscopy (range 3-58%). To determine whether this fall in PEFR following bronchoscopy reflected bronchospasm or the effect of sedation, PEFR and spirometric tests were performed during the two hours following bronchoscopy in a further study of 15 symptomatic asthmatic subjects and 20 non-asthmatic controls. To examine the effect on asthma control, asthmatic patients recorded PEFR, symptom scores, and medication use for two weeks before and after bronchoscopy.

RESULTS

After bronchoscopy with bronchial biopsies there was no difference between the median maximal fall in either PEFR or arterial oxygen saturation between the 15 asthmatic patients (10.4% and 4%, respectively) and 20 controls (12% and 3%). Moreover, there were no significant changes in PEFR, symptom score, or medication use by the asthmatic subjects in the two weeks after bronchoscopy when compared with the two weeks before bronchoscopy.

CONCLUSIONS

Fibreoptic bronchoscopy is well tolerated in asthmatic subjects. Falls in PEFR in both asthmatic and non-asthmatic subjects after bronchial biopsy may reflect the effects of sedation rather than bronchospasm. Additional bronchoalveolar lavage may cause bronchoconstriction. Careful monitoring is therefore essential. Peak flow monitoring up to two weeks after bronchoscopy with bronchial biopsy revealed no delayed effects on asthma control.

Increased interleukin-10 messenger RNA expression in atopic allergy and asthma

Interleukin-10 (IL-10) inhibits T-lymphocyte proliferation and production of cytokines. We have examined expression of IL-10 messenger RNA (mRNA) in atopic asthma and in allergen and tuberculin skin responses by in situ hybridization. The proportion of bronchoalveolar lavage (BAL) cells positive for IL-10 mRNA was increased in a group of 10 symptomatic asthmatics when compared with control subjects (17.5% versus 5.2% BAL cells positive; P < 0.001). In a separate group of six mild atopic asthmatics, there was an increased proportion of BAL cells positive for IL-10 mRNA 24 h after allergen inhalation challenge compared with diluent challenge BAL from the same subjects (24% versus 10%; P < 0.005). By simultaneous in situ hybridization and immunocytochemistry, IL-10 mRNA was localized to both CD3+ T cells and CD68+ alveolar macrophages in BAL, with a significantly more prominent T-cell signal in the symptomatic asthmatics compared with control subjects and after allergen challenge compared with diluent challenge of the mild asthmatic subjects. It has been suggested that IL-10 production is a late event after T-cell activation. To examine kinetics and specificity of IL-10 mRNA expression, skin biopsies were obtained from atopic, tuberculin-sensitive subjects at 1, 6, and 48 h after cutaneous injection of allergen or tuberculin. With both stimuli, there was an increase in IL-10 mRNA-positive cells at 6 h when compared with control sites injected with appropriate diluent which were biopsied 24 h after injection (P < 0.01 for allergen and P < 0.02 for tuberculin). These findings are compatible with the hypothesis that IL-10 mRNA is expressed in both macrophages and T lymphocytes in the airway in asthma and that IL-10 mRNA expression is induced from T lymphocytes in response to allergen. This response may also occur in other types of cell-mediated inflammation.

Stereotactic uses beyond core biopsy: model development for minimally invasive treatment of breast cancer through interstitial laser hyperthermia

Light of a Nd:YAG laser presented through a fiberoptic cable to a diffusing tip can be adapted to mammographic stereotactic instruments now used for core biopsy in the hyperthermic endoablation of breast cancer. This approach to cancer destruction extends breast preservation to the point of no observable surface skin change. The initial analysis characterizes the effects of laser endohyperthermia in a physical model as well as in tissue, both ex vivo and in vivo, to create a reliable technique that will lead to human trials. A fiberoptic cable with a diffusing quartz tip placed deep within soft tissue can pass light of a neodymium laser and consequent thermal energy for the destruction of surrounding soft tissues. Because breast cancer occurs with greatest frequency in the involuted breasts of women more than 50 years of age and because this tissue is predominantly fibro-fatty in nature, our work has concentrated on model development and the determination of heat distribution and destruction of fat and fibro-fatty tissue. Following the development of a physical model, time-temperature courses were found to be similar in ex vivo human breast tissue and subcutaneous porcine fat. This led to in vivo porcine studies that confirmed similar time-temperature courses. For tissues brought to a range of 60 degrees C to 80 degrees C and sustained for the better part of 20 minutes, gross and histological analyses reveal complete destruction over a 1 1/2 cm radial region around the laser tip. This approach offers great promise for the treatment of stereotactically biopsied small T1 breast carcinomas.

Prednisolone treatment in asthma. Reduction in the numbers of eosinophils, T cells, tryptase-only positive mast cells, and modulation of IL-4, IL-5, and interferon-gamma cytokine gene expression within the bronchial mucosa

We have tested the hypothesis that the beneficial effects of corticosteroids in asthma may result from reduction in the number of inflammatory cells infiltrating the bronchial mucosa with inhibition of cytokine gene expression. A randomized parallel group study was performed in 18 moderately severe asthmatic patients in whom an elective trial of corticosteroid treatment was indicated. Fiberoptic bronchoscopy was performed and bronchial biopsies taken from segmental carinae before and after 2 wk treatment with prednisolone (0.6 mg/kg/d) or matched placebo tablets. Immunohistology was performed on 6-microns cryostat sections using monoclonal antibodies. The number of cells expressing cytokine messenger RNA (mRNA) was assessed by in situ hybridization using S35-labeled riboprobes. When prednisolone- and placebo-treated groups were compared there was a decrease in airway methacholine responsiveness (p < 0.01) and an increase in FEV1 (p < 0.05) after prednisolone. This was accompanied by a reduction in CD3+ T lymphocytes (p < 0.05), "activated" EG2+ eosinophils (p < 0.02), and tryptase-only (mucosal-type) MCT cells (p < 0.02) but not MCTC (tryptase+chymase positive) cells in prednisolone-treated patients. In prednisolone-treated patients there was also a reduction in the number of cells expressing mRNA for interleukin-4 (IL-4, p < 0.01), and interleukin-5 (IL-5, p < 0.03) and an increase in cells expressing mRNA for interferon-gamma (IFN-gamma) (p < 0.01). These results support the view that corticosteroid treatment in asthma may act by modulation of cytokine expression with consequent inhibition of the local bronchial inflammatory infiltrate and tissue eosinophilia.

Responders to antidepressant drug treatment: a study comparing nefazodone, imipramine, and placebo in patients with major depression

BACKGROUND

Nefazodone hydrochloride, an antidepressant that acts as a 5-HT2 antagonist and serotonin (5-HT) and norepinephrine uptake inhibitor, was evaluated in a double-blind, imipramine- and placebo-controlled study involving 128 patients with major depression.

METHOD

Eligible patients were randomly assigned to receive placebo (2 to 6 capsules/day), imipramine (100 to 300 mg/day), or nefazodone (200 to 600 mg/day) for 8 weeks. The principal efficacy outcome measure assessed was the number of patients who experienced an adequate response during treatment.

RESULTS

Based on global improvement (Clinical Global Impressions-Improvement), 67% of nefazodone-treated patients (p < or = .01) and 63% of imipramine-treated patients (p < or = .05) responded during 8 weeks of treatment, compared with 36% of placebo controls. Sixty-two percent of nefazodone-treated, 53% of imipramine-treated, and 26% of placebo-treated patients had 17-item Hamilton Rating Scale for Depression (HAM-D-17) scores < or = 10 on completion of acute treatment. Nefazodone-treated patients had a lower incidence of premature treatment discontinuation and fewer dropouts for adverse events than the imipramine group.

CONCLUSION

In a three arm comparison with imipramine and placebo, nefazodone had the greatest number of patients with major depression who responded to therapy. Nefazodone, a new antidepressant with novel pharmacology, is a well-tolerated, efficacious antidepressant.

The safety profile of nefazodone

Comprehensive review of safety data from approximately 3500 patients who received nefazodone in premarketing clinical trials demonstrates the drug to be very well tolerated, with a favorable side effect profile compared with other antidepressant drugs. Nefazodone treatment was associated with fewer side effects than were the control drugs. The incidence of side effects was generally low, and treatment discontinuations for adverse effects were less frequent with nefazodone than with imipramine and comparable with fluoxetine. No late-appearing side effects or toxicity emerged during the long-term treatment (1 year or longer) of several hundred patients. There were no drug-related fatalities and no evidence that nefazodone caused specific organ toxicity, although some cardiovascular side effects were noted (e.g., asymptomatic reduced systolic blood pressure, asymptomatic sinus bradycardia). Experience in 488 elderly patients treated with nefazodone yielded no evidence of increased susceptibility of older patients to nefazodone-associated adverse experiences, including those pertaining to the cardiovascular system. However, treatment should be initiated at a reduced dose in elderly patients because of reduced hepatic clearance of nefazodone in this age group. Final dose range may be similar in healthy younger and older patients. Although nefazodone may interact with some other medications (e.g., increases at steady state in AUC: alprazolam, twofold; triazolam, fourfold), drug-drug interactions involving patients have been clinically minor. On the basis of the inhibition of cytochrome P450 3A4 isoenzyme by nefazodone in vitro, coadministration of terfenadine or astemizole with nefazodone is contraindicated because nefazodone can increase the plasma levels of these two drugs. Extensive clinical experience provides substantial evidence that nefazodone is an extremely safe and effective treatment for depression, with important advantages over existing therapies. Therapeutic benefits include a low incidence of clinically troublesome side effects and lack of unwanted psychic activation, sexual dysfunction, weight change, and the cardiotoxicity of other antidepressants.