p38 mitogen-activated kinase is a bidirectional regulator of human fibroblast collagenase-1 induction by three-dimensional collagen lattices

When fibroblasts are cultured in contracting collagen matrices, matrix metalloproteinase-1 (MMP-1, collagenase-1) is induced. In the present study we demonstrate that p38alpha mitogen-activated protein kinase (p38alpha MAPK) plays a bi-directional role in the MMP-1 response to contracting floating collagen lattices (fl-coll). fl-coll, but not attached collagen lattices (att-coll), co-ordinately increased expression of MMP-1 and activities of p38alpha and MKK3/6 (MAPK kinase 3/6). However, treatment of primary fibroblasts cultured in fl-coll with increasing doses of SB203580, an inhibitor of p38alpha and p38beta, caused a bipolar pattern of MMP-1 expression. Partial inhibition of p38 MAPK activity resulted in the lowest level of MMP-1 expression, whereas total inhibition of p38 activity led to MMP-1 levels as high as in the absence of inhibitor. The activation/inhibition of p38alpha was apparently responsible for the observed phenomena, as supported by three lines of evidence. (1) p38alpha was the predominant isoform sensitive to SB203580 in primary fibroblasts. (2) Fibroblasts transfected with increasing dose of a dominant negative p38alpha (p38DN) similarly demonstrated the bipolar pattern of MMP-1 expression induced by fl-coll. (3) The bipolar MMP-1 expression occurred during the gradual, linear inhibition of p38alpha kinase activity by both inhibitors, SB203580 and p38DN. Nuclear factor-kappaB (NF-kappaB), a previously identified positive regulator of MMP-1 expression induced by fl-coll [Xu, Zutter, Santoro and Clark (1998) J. Cell Biol. 140, 709-719] was mediated by fl-coll-activated p38alpha. However, the fl-coll-induced expression of MMP-1 facilitated by p38alpha suppression was maintained independent of NF-kappaB activity, suggesting the existence of a p38alpha-dependent antagonistic pathway. We conclude that fl-coll-induced MMP-1 expression is the net outcome of opposing effects mediated by p38alpha. Therefore, the level of p38alpha kinase activity may provide a fine-tuned control of MMP-1 gene expression in response to biomechanical signals.

What are the most promising strategies for the therapeutic immunomodulation of allergic diseases?

Specific immunotherapy and other immunomodulatory strategies have long been a stronghold in the management of allergic diseases. In particular, "immunodeviation-therapy" or "vaccination for allergies", i.e. the redirection of Th2-type immune responses towards a Th1-response pattern, has become an ever more popular concept. The present feature of CONTROVERSIES complements our previous discussion of atopy (Röcken et al., Exp Dermatol 7: 97--104, 1998), and is dedicated to a critical analysis of the general problems and limitations one faces with the main immunomodulatory strategies traditionally considered in this context. We also explore alternative approaches that appear promising in order to achieve both a more effective and/or a more specific immunotherapy of allergic diseases. Given that the mast cell remains a key protagonist in the pathogenesis of allergic diseases finally, this feature examines how innovative, more selectively mast cell-targeted strategies may be developed for the management of allergic diseases.

Recurrent Achromobacter piechaudii bacteremia in a patient with hematological malignancy

We describe a recurrent bacteremia caused by Achromobacter (formerly Alcaligenes) piechaudii in association with an intravenous catheter in an immunocompromised 73-year-old man. This is the first reported case of bacteremia due to A. piechaudii.

False-positive reduction in CAD mass detection using a competitive classification strategy

High false-positive (FP) rate remains to be one of the major problems to be solved in CAD study because too many false-positively cued signals will potentially degrade the performance of detecting true-positive regions and increase the call-back rate in CAD environment. In this paper, we proposed a novel classification method for FP reduction, where the conventional "hard" decision classifier is cascaded with a "soft" decision classification with the objective to reduce false-positives in the cases with multiple FPs retained after the "hard" decision classification. The "soft" classification takes a competitive classification strategy in which only the "best" ones are selected from the pre-classified suspicious regions as the true mass in each case. A neural network structure is designed to implement the proposed competitive classification. Comparative studies of FP reduction on a database of 79 images by a "hard" decision classification and a combined "hard"-"soft" classification method demonstrated the efficiency of the proposed classification strategy. For example, for the high FP sub-database which has only 31.7% of total images but accounts for 63.5% of whole FPs generated in single "hard" classification, the FPs can be reduced for 56% (from 8.36 to 3.72 per image) by using the proposed method at the cost of 1% TP loss (from 69% to 68%) in whole database, while it can only be reduced for 27% (from 8.36 to 6.08 per image) by simply increasing the threshold of "hard" classifier with a cost of TP loss as high as 14% (from 69% to 55%). On the average in whole database, the FP reduction by hybrid "hard"-"soft" classification is 1.58 per image as compared to 1.11 by "hard" classification at the TP costs described above. Because the cases with high dense tissue are of higher risk of cancer incidence and false-negative detection in mammogram screening, and usually generate more FPs in CAD detection, the method proposed in this paper will be very helpful in improving the performance of early detection of breast cancer with CAD.

The range of ocular movements decreases with aging

PURPOSE

To determine whether normal maximum versions change as a function of age.

METHODS

One hundred twenty-four healthy subjects without any history of strabismus, ocular or periocular surgery, or major illness were examined to confirm visual acuity better than 20/60 in each eye and the absence of strabismus. Maximum sustained elevation, depression, dextroversion, and levoversion were quantified by using a standardized lateral version light-reflex (LVR) test.

RESULTS

Subjects ranged in age from 23 to 84 years. All LVR measurements were converted into degrees of eye rotation assuming standard globe size. For each maximal gaze position, the regression line (whether determined directly or scaled against historical normal values) was formed by plotting the LVR measurements versus age had a negative slope significantly different than zero (P =.0001 for all). Depression had a significantly smaller decrease in LVR measurement with age (-0.5% per year) than elevation (-1% per year, P = .0001), adduction (-0.8% per year, P = .0001), or abduction (-0.7% per year, P = .0017). Elevation had the largest decrease in LVR measurement with age compared with depression and abduction (P = .003).

CONCLUSION

As measured by LVR, the maximum versions into extremes of gaze decrease by an average of 0.5% to 1.0% per year of life between the third and ninth decade. The version least affected and most affected by age is depression and elevation, respectively. Age should be considered when assessing versions for evidence of rectus muscle overaction and underaction.

Does passive smoking increase the frequency of health service contacts in children with asthma?

BACKGROUND

Passive smoking is a major cause of respiratory morbidity in children. However, few studies give accurate estimates of the health effects of passive smoking in children with asthma using an objective measure of exposure. The effects of passive smoking using salivary cotinine levels to measure exposure were investigated.

METHODS

A sample of 438 children aged 2-12 years with asthma who had a parent who smoked were recruited in Tayside and Fife, Scotland. Health service contacts for asthma, assessed from GP case records, were used as a proxy for morbidity.

RESULTS

A weak U-shaped relationship was found between the salivary cotinine level and health service contacts for asthma: compared with low cotinine levels those with moderate cotinine levels had a reduced contact rate (relative rate (RR) = 0.91, 95% confidence interval (CI) 0.80 to 1.05), whereas high cotinine levels were associated with an increased rate of contact (RR = 1.19, 95% CI 1.05 to 1.37). In contrast, a strong association was seen with the amount the parent reported smoking in front of the child: the higher the level the fewer visits were made for asthma (RR for everyday exposure = 0.66, 95% CI 0.56 to 0.77). This effect was not seen for non-respiratory visits. Demographic factors, age of child, and number of children in the family all had a powerful effect on the number of visits for asthma. The parents' perception of asthma severity was associated with visit frequency independent of actual severity (derived from drug treatment).

CONCLUSION

High levels of parental smoking in the home are associated with a reduction in health care contacts for asthma. This could be due to a lack of awareness of asthma symptoms among heavy smokers or a reluctance to visit the GP. Children with asthma who have parents who smoke heavily may not be receiving adequate management.

Angiogenesis in wound healing

During wound healing, angiogenic capillary sprouts invade the fibrin/fibronectin-rich wound clot and within a few days organize into a microvascular network throughout the granulation tissue. As collagen accumulates in the granulation tissue to produce scar, the density of blood vessels diminishes. A dynamic interaction occurs among endothelial cells, angiogenic cytokines, such as FGF, VEGF, TGF-beta, angiopoietin, and mast cell tryptase, and the extracellular matrix (ECM) environment. Specific endothelial cell ECM receptors are critical for these morphogenetic changes in blood vessels during wound repair. In particular, alpha(v)beta3, the integrin receptor for fibrin and fibronectin, appears to be required for wound angiogenesis: alpha(v)beta3 is expressed on the tips of angiogenic capillary sprouts invading the wound clot, and functional inhibitors of alpha(v)beta3 transiently inhibit granulation tissue formation. Recent investigations have shown that the wound ECM can regulate angiogenesis in part by modulating integrin receptor expression. mRNA levels of alpha(v)beta3 in human dermal microvascular endothelial cells either plated on fibronectin or overlaid by fibrin gel were higher than in cells plated on collagen or overlaid by collagen gel. Wound angiogenesis also appears to be regulated by endothelial cell interaction with the specific three-dimensional ECM environment in the wound space. In an in vitro model of human sprout angiogenesis, three-dimensional fibrin gel, simulating early wound clot, but not collagen gel, simulating late granulation tissue, supported capillary sprout formation. Understanding the molecular mechanisms that regulate wound angiogenesis, particularly how ECM modulates ECM receptor and angiogenic factor requirements, may provide new approaches for treating chronic wounds.

Calreticulin modulates capacitative Ca2+ influx by controlling the extent of inositol 1,4,5-trisphosphate-induced Ca2+ store depletion

Calreticulin (CRT) is a highly conserved Ca(2+)-binding protein that resides in the lumen of the endoplasmic reticulum (ER). We overexpressed CRT in Xenopus oocytes to determine how it could modulate inositol 1,4,5-trisphosphate (InsP(3))-induced Ca(2+) influx. Under conditions where it did not affect the spatially complex elevations in free cytosolic Ca(2+) concentration ([Ca(2+)](i)) due to InsP(3)-induced Ca(2+) release, overexpressed CRT decreased by 46% the Ca(2+)-gated Cl(-) current due to Ca(2+) influx. Deletion mutants revealed that CRT requires its high capacity Ca(2+)-binding domain to reduce the elevations of [Ca(2+)](i) due to Ca(2+) influx. This functional domain was also required for CRT to attenuate the InsP(3)-induced decline in the free Ca(2+) concentration within the ER lumen ([Ca(2+)](ER)), as monitored with a "chameleon" indicator. Our data suggest that by buffering [Ca(2+)](ER) near resting levels, CRT may prevent InsP(3) from depleting the intracellular stores sufficiently to activate Ca(2+) influx.

Three-dimensional location of human rectus pulleys by path inflections in secondary gaze positions

PURPOSE

Connective tissue pulleys serve as the functional mechanical origins of the extraocular muscles (EOMs). Anterior to these pulleys, EOM paths shift with gaze to follow the scleral insertions, whereas posterior EOM paths are stable in the orbit. Inflections in EOM paths produced by gaze shifts can be used to define the functional location of pulleys in three dimensions (3-D).

METHODS

Contiguous magnetic resonance images in planes perpendicular to the orbital axis spanned the anteroposterior extents of 22 orbits of 11 normal adults with the eyes in central gaze, elevation, depression, abduction, and adduction. Mean EOM cross-sectional area centroids represented in a normalized, oculocentric coordinate system were plotted over the length of each EOM to determine paths. Path inflections were identified to define pulley locations in 3-D.

RESULTS

All rectus EOM paths exhibited in secondary gaze positions distinct inflections 3 to 9 mm posterior to globe center, which were consistent across subjects. The globe center and the lateral rectus pulley translated systematically in the orbit with lateral gaze, whereas other pulleys remained stable relative to the orbit.

CONCLUSIONS

Distinct inflections in rectus EOM paths in secondary gaze positions confirm the existence of pulleys and define their locations in 3-D. The globe and lateral rectus pulley translate systematically with gaze position. The EOM pulleys may simplify neural control of eye movements by implementing a commutative ocular motor plant in which commands for 3-D eye velocity are effectively independent of eye position.

Scottish Asthma Management Initiative

OBJECTIVES

To describe the development process of a system that links audit, research and patient care and to detail the lessons learned from establishing a Scotland wide asthma management initiative.

DESIGN, SETTING AND SUBJECTS

Health Boards and practices throughout Scotland were invited to participate in an initiative which links review of care, guideline implementation, chronic disease management (CDM) approval and post-graduate education for doctors (PGEA) and nurses (PREP). Participating practices were given the materials to review 30 patients randomly selected from their asthma register. Health service resource use and drugs prescribed over a retrospective 12 month period were recorded for each patient using paper or electronic materials. All patients were invited for clinical assessment.

RESULTS

A two-tier management system proved effective. Twelve of the 15 Scottish health authorities agreed to recognise the audit for automatic CDM approval although the negotiation process was prolonged; 566 practices from all parts of Scotland have expressed an interest in the initiative. Provision of distance learning material linked to PGEA accreditation is free to general practitioners (GP's) and is a useful incentive for participation. To date 42 GPs have completed the distance learning element.

CONCLUSION

The Scottish Asthma Management Initiative has provided the opportunity for all sectors of the health service in Scotland to work together to explore innovative ways to improve the management and care of chronic disease. Participation in an initiative linked to guidelines, education and CDM approval is an excellent way to facilitate health professionals to improve care.

Fibrin sealant in wound repair: a systematic survey of the literature

Fibrin sealants have recently been approved for clinical use in the US by the FDA and have been available for clinical use in Europe for years. The indication for use in the US is haemostasis. Nevertheless, both commercial and non-commercial fibrin sealant preparations are also for wound healing and for prevention of abdominal adhesions in the US and Europe. To the non-cognoscenti of fibrin sealants, their use to promote wound repair and to prevent abdominal adhesions appears contradictory since an agent that promotes connective tissue repair might be expected to promote abdominal adhesion rather than prevent them. In this systematic survey of the animal and clinical data evidence is presented that supports both off-label uses. However there is much inconsistency in the data secondary to the use of various fibrin sealant preparations, different animal models and clinical situations and different application techniques. It is clear from this survey that standard preparation and application of fibrin sealant for a particular surgical setting are needed to resolve the many apparent discrepancies in the literature. A corollary to this is the likelihood that different fibrin sealant preparations may be preferred for different clinical situations.

Deep venous thrombosis: detection by using indirect CT venography. The Pulmonary Angiography-Indirect CT Venography Cooperative Group

PURPOSE

To assess the clinical benefits of performing indirect computed tomographic (CT) venography after pulmonary CT angiography to detect deep venous thrombosis (DVT) in patients suspected of having a pulmonary embolism.

MATERIALS AND METHODS

The authors prospectively enrolled 541 consecutive patients who underwent pulmonary CT angiography for suspected pulmonary embolism at seven institutions. Using a protocol that optimizes venous enhancement without additional contrast material injection, the authors obtained contiguous images from the pelvis to the popliteal fossa. Ultrasonography (US) also was performed in 116 patients.

RESULTS

DVT was found at indirect CT venography in 45 (8%), and pulmonary embolism was found at pulmonary CT angiography in 91 (17%) of 541 patients. Among the 45 patients with DVT, DVT occurred in 16 patients who had no pulmonary embolism at pulmonary CT angiography, which increased the diagnosis of thromboembolic disease by 18%. Among 116 patients who underwent US and indirect CT venography, 15 had DVT at US, and in all 15, DVT also was seen at indirect CT venography. In four additional cases, DVT was seen at only indirect CT venography.

CONCLUSION

Among patients suspected to have pulmonary embolism, a substantial number had DVT in the absence of pulmonary embolism. Combined pulmonary CT angiography-indirect CT venography can depict these cases with accuracy comparable to that of US and thus could have a significant effect on patient care.

Facial asymmetry in superior oblique muscle palsy and pulley heterotopy

INTRODUCTION

Some observers have considered facial asymmetry as characteristic of congenital superior oblique muscle (SO) palsy. However, recent orbital imaging studies have determined that incomitant vertical strabismus resembling SO palsy can be caused by heterotopic rectus muscle pulleys. This finding suggests that facial asymmetry may predict the presence of abnormal orbital anatomy rather than be secondary to ocular torticollis.

METHODS

Subjects who underwent orbital computed tomography or magnetic resonance imaging were divided into 5 groups based on clinical evaluation and previously established imaging criteria: (1) congenital SO palsy; (2) acquired SO palsy; (3) strabismus with pulley heterotopy; (4) strabismus without SO palsy or pulley heterotopy; and (5) orthotropic subjects. Frontal photographs were digitized and the following 3 facial morphometric features recorded: (1) angle of inclination of each orbit; (2) relative facial size; and (3) facial angle.

RESULTS

The 79 subjects who underwent imaging were divided into the 5 groups as follows: 6 with congenital SO palsy; 7 with acquired SO palsy; 20 with pulley heterotopy; 26 with strabismus without SO palsy or pulley heterotopy; and 20 control subjects. All subjects with either congenital or acquired SO palsy had torticollis. Multivariate analysis demonstrated no significant differences in any of the 3 facial morphometric features among any of the groups.

CONCLUSION

Facial asymmetry as assessed by these 3 morphometric features is not useful in distinguishing between congenital SO palsy or pulley heterotopy and other acquired forms of strabismus. This finding casts doubt on the relationship between ocular torticollis and facial asymmetry.

Role of redox-regulated transcription factors in inflammation, aging and age-related diseases

A progressive rise of oxidative stress due to the altered redox homeostasis appears to be one of the hallmarks of the aging process. Reactive oxygen species (ROS) also serve as signaling agents for inflammation, a systemic defensive reaction against microbial pathogens and other foreign bodies. Changes in the pattern of gene expression through ROS-sensitive transcription factors give rise to both aging and inflammation phenotypes. Chronic oxidative stress and inflammatory reaction also lead to many age-associated diseases such as atherosclerosis and arthritis. Transcription factors that are directly influenced by ROS and proinflammatory cytokines include nuclear factor kappa B (NF-kappaB), activator protein 1 (AP-1), specificity protein 1 (Sp1), peroxisome proliferator-activated receptors (PPARs) and other members of the nuclear receptor superfamily. Here we describe the basic components of the intracellular redox control machinery and their dysregulation with age leading to altered transcription factor function and age-associated pathophysiology.

Adult-onset recalcitrant eczema: a marker of noncutaneous lymphoma or leukemia

BACKGROUND

Generalized eczema or erythroderma may be the presenting sign of cutaneous T-cell lymphoma. Additionally, intractable pruritus has been associated with Hodgkin's lymphoma. However, reports of adult-onset eczematous dermatitis has rarely been linked to noncutaneous lymphoproliferative disorders.

OBSERVATIONS

We observed one patient in 1993 who had the onset of intractable dermatitis characterized by prurigo nodularis-like lesions and widespread erythematous plaques. After 18 months of cutaneous symptoms he experienced dyspnea. At this time Hodgkin's disease was diagnosed. This observation prompted us to evaluate subsequent patients with adult-onset eczema who were poorly responsive to therapy and in whom an obvious cause could not be determined. Over the next 24 months we identified an additional 2 patients with lymphoma who met this criteria.

CONCLUSION

Unexplained eczema of adult onset may be associated with an underlying lymphoproliferative malignancy. When a readily identifiable cause (eg, contactants, drugs, or atopy) is not found, a systematic evaluation should be pursued. Patients should be evaluated with a careful physical examination, complete blood cell counts, peripheral blood smears, chest roentgenography, computed tomography of the chest and abdomen, and serum protein electrophoresis.

Incidence and predictors of reinfection with Trichomonas vaginalis in HIV-infected women

BACKGROUND AND OBJECTIVES

The presence of sexually transmitted infections (STIs) may facilitate transmission of HIV to uninfected partners.

GOAL

To describe the incidence of reinfection with Trichomonas vaginalis in HIV-infected women and to assess predictors of reinfection.

STUDY DESIGN

A retrospective cohort study using data abstracted from medical records of HIV-infected women with at least one diagnosis of trichomoniasis.

RESULTS

Approximately one third (36%) of the study population was reinfected with T vaginalis during the follow-up period, with an incidence of 16.4 reinfections per 100 person years. Significant predictors of reinfection included history of another STI (hazard ratio, 1.52; 95% CI, 1.08-2.14) and becoming pregnant during the follow-up period (hazard ratio, 0.59; 95% CI, 0.39-0.87).

CONCLUSIONS

There is a high rate of reinfection with T vaginalis in HIV-infected women. Further research that includes information on sexual partners should be conducted to better describe the reinfection patterns of trichomoniasis.

Positron emission tomography in initial staging and diagnosis of persistent or recurrent disease

Positron emission tomography (PET) constitutes a major advance in the diagnosis, staging, prognostic assessment, and follow-up of lung cancer. However, it is not a magic bullet that can solve all of the uncertainties that beguile the imaging of this disease. Small lesions, particularly those in the brain, may often be missed with PET, and three-dimensional localization of suspected sites may also be unreliable. We are still learning how best to apply this new technology in an environment that demands the efficient use of medical resources. PET will probably be used most enthusiastically in the prethoracotomy staging of patients who are considered operable or probably operable on the basis of computed tomography and in the assessment of treatment response and disease recurrence when clinical management will be determined by prompt recognition of these events.

Melanoma lymphoscintigraphy and lymphatic mapping

Lymphoscintigraphy in melanoma has proven to be a reliable method to identify regional lymph nodes at risk for metastases. The first lymph node to drain a cutaneous lesion, the sentinel lymph node (SLN), is predictive of the metastatic status of the regional lymph node group. Lymphatic mapping allows for the identification of the SLN and for selective lymph node sampling. Selective lymph node sampling is less invasive and because only a small quantity of high-risk tissue is submitted for pathological examination, it allows for a more complete and comprehensive pathological examination, which identifies melanoma with up to 100 times the sensitivity of conventional examinations.