Prevention of exacerbations of chronic obstructive pulmonary disease with tiotropium, a once-daily inhaled anticholinergic bronchodilator: a randomized trial

BACKGROUND

Patients with chronic obstructive pulmonary disease (COPD) frequently develop exacerbations, leading to major clinical and health resource use ramifications.

OBJECTIVE

To prospectively evaluate the effectiveness of a long-acting inhaled anticholinergic bronchodilator, tiotropium, in reducing COPD exacerbations and exacerbation-related health care utilization.

DESIGN

Randomized, double-blind study.

SETTING

26 Veterans Affairs medical centers.

PATIENTS

1829 patients with moderate to severe COPD (mean baseline FEV(1), 36% predicted).

INTERVENTION

Once-daily tiotropium (18 microg) or placebo for 6 months. Patients otherwise received usual care, except for other anticholinergic bronchodilators.

MEASUREMENTS

The coprimary end points were the percentage of patients with a COPD exacerbation and the percentage of patients with a COPD-related hospitalization.

RESULTS

Tiotropium significantly reduced the percentage of patients experiencing 1 or more exacerbations compared with placebo (27.9% vs. 32.3%, respectively; difference, -5.7 percentage points [95% CI, -10.4 to -1.0 percentage points]; P = 0.037). Fewer tiotropium patients were hospitalized because of COPD exacerbation (7.0% vs. 9.5%, respectively; difference, -3.0 percentage points [CI, -5.9 to -0.1 percentage points]; P = 0.056), although this difference was of borderline statistical significance. Analysis of secondary outcomes indicates that tiotropium may lengthen the time to first COPD exacerbation (P = 0.028) and reduce health care utilization for exacerbations, including the frequency of hospitalizations (P = 0.047), unscheduled clinic visits (P = 0.019), and days of antibiotic treatment (P = 0.015). Tiotropium did not statistically significantly reduce all-cause hospitalization rates.

LIMITATIONS

Trial participants were enrolled from 1 health care system, and 99% were men. The follow-up period extended for only 6 months.

CONCLUSIONS

Tiotropium reduces COPD exacerbations and may reduce related health care utilization in patients with moderate to severe COPD.

Memory after menopause: preliminary considerations of hormone influence on cognitive functioning

Oestrogen has been shown to have a wide variety of organisational and activating effects on brain structure and function. Despite the significant amount of research investigating the relation and effects of oestrogen to cognitive performance in menopausal women over the past two decades, studies have failed to produce consistent findings. This paper reports on evaluations of eighty-one community-based postmenopausal Australian women comparing current, past and never users of hormone therapy (HT) on a wide range of cognitive measures of general, verbal and visual memory, delayed recall, attention, concentration and verbal comprehension. Few significant differences were found among the three groups in the demographic profile, health status or psychological functioning. Although never users had significantly lower scores on verbal memory than past users, the differences were not statistically significant when adjustments were made controlling for age, education level, verbal comprehension, attention and concentration. These findings challenge long-held beliefs regarding the usefulness of oestrogen supplements as a protective factor against cognitive decline in older women's later years.

Recent quitters' interest in recycling and harm reduction

Many smoking cessation attempts are followed by failure or relapse. The optimal time to initiate a new quit attempt is not known. Administrative databases documenting recent use of a pharmacological aid for smoking cessation provide access to a population of smokers recently in the action phase of quitting. This study describes interest in further treatment among this population. A total of 2,340 smokers from the Minneapolis Veterans Administration Medical Center received prescriptions for a smoking cessation aid during an 18-month period. We conducted a cross-sectional survey of a random sample of this population a minimum of 3 months following the prescription, using a structured telephone interview (N=391). The response rate was 75.8%. The 1-month point-prevalent abstinence rate was 19.7%. Of continuing smokers, 98% were willing to make another quit attempt--50% immediately, and 28% within 1 month. There was no relationship between time since the last quit attempt and interest in trying again immediately. Some 95% of continuing smokers were willing to try a reduction strategy. Of these, 82.7% were interested in using nicotine replacement therapy (NRT) to accomplish this goal. Most cessation programs do not systematically approach participants who relapse. These data suggest that this population would welcome further help in quitting or reducing smoking shortly following failure, and that smokers do not commonly relapse to a precontemplation stage of change.

Crisis intervention for people with severe mental illnesses

BACKGROUND

A particularly difficult challenge for community treatment of people with serious mental illnesses is the delivery of an acceptable level of care during the acute phases of severe mental illness. Crisis intervention models of care were developed as a possible solution.

OBJECTIVES

To review the effects of a crisis intervention model for anyone with serious mental illness experiencing an acute episode, compared to 'standard care'.

SEARCH STRATEGY

Searches of 1998 were updated with a search of the Cochrane Schizophrenia Group's Register of trials (July 2003).

SELECTION CRITERIA

All randomised controlled trials of crisis intervention models versus standard care for people with severe mental illnesses.

DATA COLLECTION AND ANALYSIS

Working independently, reviewers selected and critically appraised studies, extracted data and analysed on an intention-to-treat basis. Where possible and appropriate we calculated risk ratios (RR) and their 95% confidence intervals (CI), with the number needed to treat (NNT). For continuous data Weighted Mean Differences (WMD) were calculated.

MAIN RESULTS

This 2003 update includes no new studies. Five studies, none purely investigating crisis intervention, are included and 21 excluded. All included trials used a form of home care for acutely ill people, which included elements of crisis intervention. 45% of the crisis/home care group were unable to avoid hospital admission during their treatment period. Home care, however, may help avoid repeat admissions (n = 465, 3 randomised controlled trials, RR 0.72 CI 0.54 to 0.92, NNT 11 CI 6 to 97), but these data are heterogeneous (I-squared 86%). Crisis/home care reduces the number of people leaving the study early (n = 594, 4 randomised controlled trials, RR lost at 12 months 0.74 CI 0.56 to 0.98, NNT 13 CI 7 to 130), reduces family burden (n = 120, 1 randomised controlled trial, RR 0.34 CI 0.20 to 0.59, NNT 3 CI 2 to 4), and is a more satisfactory form of care for both patients and families. We found no differences in death or mental state outcomes. All studies found home care to be more cost effective than hospital care but all data were either skewed or unusable. No data on staff satisfaction, carer input, compliance with medication and number of relapses were available.

REVIEWERS' CONCLUSIONS

Home care crisis treatment, coupled with an ongoing home care package, is a viable and acceptable way of treating people with serious mental illnesses. If this approach is to be widely implemented it would seem that more evaluative studies are needed.

Central sensitisation and cutaneous allodynia in migraine: implications for treatment

Cutaneous allodynia, pain resulting from application of a non-noxious stimulus to normal skin, is a recently described symptom of migraine, with a potential role in directing optimal treatment for migraine attacks. Manifestations of cutaneous allodynia include discomfort when combing the hair, shaving, and wearing glasses, contact lenses, earrings or tight clothing. The exact mechanism by which a migraine attack is triggered is not known, but it has been theorised that, in some patients, once the attack has begun, central neurons can propagate information about the pain process without the need for further external stimuli. This process is termed central sensitisation. The trigeminal nerves, which innervate intracranial and extracranial tissues, account for head pain and other symptoms in migraine. The first-order neurons in the trigeminal ganglion receive input from the dural blood vessels, which is transmitted to second-order neurons in the trigeminal brain stem nuclear complex and is finally sent to the third-order neurons in the thalamus. Studies in humans and animals have shown that migraine pain progresses along this neural pathway, with throbbing head pain occurring early in the attack (sensitisation of first-order neurons), followed by central sensitisation and cutaneous allodynia within the referred pain area (second-order) and finally extracephalic allodynia (third-order). The data also indicate that once central sensitisation is established in the second- and third-order neurons, migraine treatment designed to prevent the initiation of central sensitisation can lessen the pain to some extent but cannot reverse it. Thus, treatment affecting the initiation of central sensitisation should be administered immediately after the onset of migraine pain to prevent intracranial hypersensitivity and the establishment of allodynia. The serotonin 5-HT(1B/1D) agonist anti-migraine agents (the 'triptans') block meningeal nociceptor transmission at presynaptic sites in the dorsal horn. Studies have shown that triptan therapy can abort pain prior to the development of central sensitisation, but not after allodynia has been established. Therefore, in the subset of patients who report symptoms of cutaneous allodynia with migraine attacks, early initiation of triptan therapy is currently the best intervention to achieve rapid, complete and sustained pain relief.

Endothelial monocyte-activating polypeptide-II (EMAP-II): a novel inducer of lymphocyte apoptosis

The novel, proinflammatory cytokine endothelial monocyte-activating polypeptide-II (EMAP-II) was first found in tumor cell supernatants. EMAP-II is closely related or identical to the p43 auxiliary protein of the multisynthase complex, which is involved in protein synthesis. In vitro, EMAP-II induces procoagulant activity, increased expression of E- and P-selectins and tumor necrosis factor receptor-1, and ultimately, programmed cell death (apoptosis) in cultured endothelial cells. EMAP-II is also chemotactic for monocytes and neutrophils. However, the role of the p43/EMAP-II cytokine form in tumors is not understood. We hypothesized an immune-regulatory role within neoplastic tissues and investigated its effects on lymphocytes. EMAP-II causes a dose-dependent inhibition of proliferation and apoptosis in Jurkat T cells and mitogen-activated peripheral blood mononuclear cells. Coculture with DLD-1 colorectal cancer cells or media conditioned by these cells induces apoptosis in Jurkat cells, which is partially reversed by antibodies against EMAP-II. Our data suggest that EMAP-II constitutes a component of a novel, immunosuppressive pathway in solid tumors, which is not normally expressed outside the cell but in tumors, may be subject to abnormal processing and released from tumor cells.

Dopaminergic effects on electrophysiological and functional MRI measures of human cortical stimulus–response power laws

Power laws have been widely used to formulate relationships between objective intensity of stimulation and subjective intensity of sensation. We investigated the effects of dopaminergic drug treatment (sulpiride) on the relationship between somatosensory stimulus intensity and cortical response measured electrophysiologically by somatosensory-evoked potentials (SEP) and functional magnetic resonance imaging (fMRI). The intensity of stimulation was related by a simple power law to both electrophysiological and fMRI measures of cortical response, with overlapping confidence intervals for both power law exponents. Sulpiride did not modulate the power law exponent, but significantly attenuated the "gain" of both stimulus-response functions. Using path analysis we decomposed dopaminergic effects on fMRI data into an indirect component (16%), predictable by drug effects on SEP, and a direct component (84%), not explained electrophysiologically. Results indicate that sulpiride has comparable effects on power law parameters estimated from SEP and fMRI, but fMRI has superior sensitivity to detect drug effects on somatosensory cortical recruitment by graded stimulation.

Bone mineral density reference standards in adult baboons (Papio hamadryas) by sex and age

Osteoporosis is a progressive condition involving structural deterioration of bone tissue, leading to skeletal fragility and an increased susceptibility to fractures due to low bone mass and high rates of bone turnover. Areal bone mineral density (aBMD) serves as the most reliable predictor of susceptibility to osteoporotic fracture. The development of animal models, including Old World Monkeys, has been essential to studies of bone mineral density. These animals, including the baboon, exhibit many biological similarities with our own species relevant to the variation in age-related changes and pathology in bone that may make them an excellent model for studies of skeletal structure and maintenance in humans. The baboon has been shown to exhibit extensive biological similarities to humans regarding skeletal biology, but little is known about the range of normal variation in skeletal traits, such as bone mineral density, in this species. Our data, collected on baboons (Papio hamadryas) that are part of a large breeding colony at the Southwest Foundation for Biomedical Research and the Southwest National Primate Research Center (San Antonio, TX), involve 466 females and 210 males, ranging in age from 5.5 to 30 years. Student's t tests, bivariate correlations, and likelihood ratio tests show sex and age effects at all spinal sites. Age effects are minimal or absent in the forearm sites. This study is the first to characterize normal variation in aBMD in baboons, to assess the effect of age and sex on this variation, and to compare this variation to those data currently available from experimental control animals. As such, it provides much-needed reference standards that will allow researchers to evaluate the status of their animals in cross-sectional studies and more fully assess the meaning of aBMD changes in longitudinal studies.

Genetics of leptin expression in baboons

OBJECTIVE

Leptin gene expression is higher in females than in males, and is regulated by many factors including energy intake and insulin, but little is known about the inheritance of leptin gene expression. We have investigated leptin (LEP) gene express-ion, to determine whether it is heritable, and whether the difference in LEP expression between males and females has a genetic component.

STUDY POPULATION

A total of 319 baboons (Papio hamadryas) (220 females, 99 males) from a captive, pedigreed colony.

MEASUREMENTS AND METHODS

We cloned a baboon LEP cDNA, and quantified LEP mRNA expression in baboon omental adipose tissue using a ribonuclease protection assay. In addition, we assayed circulating leptin levels, adipocyte cell volume, and weight. We used maximum likelihood-based variance decomposition methods to determine the genetic architecture of LEP levels, including testing for genotype-by-sex interaction.

RESULTS

Omental LEP mRNA expression was significantly and positively correlated with weight and adipocyte cell volume in baboons. Both mRNA and plasma levels of leptin were higher in females than in males, and both measures were heritable. The results of our genetic analysis show that there was a genotype-by-sex interaction in the levels of plasma leptin, but not in omental LEP mRNA.

CONCLUSIONS

As in humans, baboon leptin mRNA and protein levels are expressed at a higher level in females than in males. We detected evidence that the plasma levels were affected by genes that are differentially expressed in males and females, while the omental mRNA levels were not. This finding suggests that the genes that differentially regulate plasma leptin levels between males and females may exert their effects on post-transcriptional processes.

Measuring cognition in menopause research: a review of test use

OBJECTIVE

To examine critically how various aspects of memory functions have been assessed in menopause-related research.

METHOD

Twenty peer-reviewed articles on the menopause and cognitive functioning published between 1991 and 2000 were identified through a computerized Medline search. All studies utilized healthy non-demented women, and assessed specific aspects of cognitive functioning using standardized tests rather than self-reporting of perceived functioning.

RESULTS

Measures used to assess attention and concentration, verbal memory, learning and verbal expression, visual memory, concept formation and reasoning have all been reviewed. Findings from studies assessing attention and concentration demonstrate inconsistent results with regard to hormone levels or menopausal status. Although five measures of verbal learning and memory have been considered, no articles published in the past decade have reported unequivocal results for any one measure. Only one study reviewed found significant differences in measures of verbal expression between hormone therapy users and non-users. In addition, no strong association between estrogen level and visual memory was identified in the studies reviewed.

CONCLUSIONS

This careful analysis demonstrates that, within the studies of cognitive abilities of menopausal women reviewed in this article, a wide variety of tests have been used. However, the body of literature considered neither consistently nor conclusively demonstrates a clear effect of exogenous hormone therapy on memory. It is suggested that verbal memory, visual memory, concept formation and reasoning should be simultaneously investigated in future research, and that covariate measures of attention and concentration, verbal expression and reasoning are also included. In addition, within each specific domain, the psychometric properties of tests, the populations they were intended to assess and the specific aspects of cognitive function they were designed to address need to be more closely considered.

The effect of selected growth factors on human anterior cruciate ligament cell interactions with a three-dimensional collagen-GAG scaffold

Our work focuses on development of a collagen-glycosamimoglycan (CG) scaffold to facilitate ligament healing in the gap between the ruptured ends of the human anterior cruciate ligament (ACL). In the present investigation, we evaluated the effects of selected growth factors on human ACL cell responses important in tissue regeneration, namely cell migration, proliferation, collagen production, and expression of alpha-smooth muscle actin (SMA).

METHODS

Explants from six human ACLs were cultured on top of a CG scaffold. Culture conditions were with either 2% FBS (control), or 2% FBS supplemented with TGF-beta1, PDGF-AB, EGF, or FGF-2. Histologic cell distribution, total DNA content, proliferation rate, rate of collagen synthesis, scaffold diameter and percentage of SMA positive cells were determined at two, three and four weeks.

RESULTS

The addition of TGF-beta1 to the culture medium resulted in increased cell number, increased collagen production and increased expression of SMA within the scaffold. Supplementation with PDGF-AB resulted in increased cell proliferation rates within the scaffold and increased collagen production. The addition of FGF-2 resulted in increased cell proliferation rates and slowed rates of scaffold shrinkage when compared with the control group.

DISCUSSION

This work suggests that certain growth factors can alter the biologic functions of human ACL cells in a CG scaffold implanted as a bridge at the site of an ACL rupture. Based on these findings, the addition of selected growth factors to an implantable CG scaffold may facilitate ligament healing in the gap between the ruptured ends of the human ACL.

Ipratropium bromide hydrofluoroalkane inhalation aerosol is safe and effective in patients with COPD

STUDY OBJECTIVE

To compare the efficacy and safety of ipratropium bromide reformulated with the chlorofluorocarbon (CFC)-free propellant hydrofluoroalkane (HFA)-134a (ipratropium bromide HFA) to that of the marketed ipratropium bromide inhalation aerosol (containing CFC) in patients with COPD.

DESIGN

This was a randomized, double-blind, parallel-group, placebo-controlled, multicenter trial. The primary efficacy parameter was acute bronchodilator response. The primary end points were peak change in FEV(1) from baseline and area under the response-time curve.

SETTING

Thirty-one clinical centers in the United States participated in this project.

PATIENTS

A total of 507 patients with moderate-to-severe COPD were randomized, and 444 patients completed the trial.

INTERVENTIONS

Twelve weeks of treatment four times daily with one of the following: ipratropium bromide HFA, 42 microg; ipratropium bromide HFA, 84 microg; HFA placebo; ipratropium bromide inhalation aerosol, 42 microg; or CFC placebo.

MEASUREMENTS AND RESULTS

Patients in all active treatment groups had significant bronchodilator responses as shown by increases in mean FEV(1) from baseline of at least 15%. Bronchodilator response in all active treatment groups was also significantly more than their respective placebo treatments based on FEV(1), area under the time-response curve from 0 to 6 h, and peak response. FVC results were similar to those seen with FEV(1). There were no significant differences in adverse events, laboratory findings, or ECG findings among the treatment groups.

CONCLUSIONS

Ipratropium bromide HFA, 42 and mgr;g, provided bronchodilation comparable to the marketed ipratropium bromide CFC, 42 and mgr;g, over 12 weeks of regular use.

Variance in fibronectin binding and fnb locus polymorphisms in Staphylococcus aureus: identification of antigenic variation in a fibronectin binding protein adhesin of the epidemic CMRSA-1 strain of methicillin-resistant S. aureus

The fnbA and fnbB genes of Staphylococcus aureus 8325-4 encode fibronectin (Fn) binding proteins FnBPA and FnBPB, which promote adherence to host tissues. Each adhesin contains three copies of a repeated D motif that binds Fn and is a target for vaccine development. In this study, we assess variability within the Fn-binding domain of the FnBP adhesins and evaluate factors that promote variance in Fn binding among clinical isolates. Based on variation in the number of fnb genes or the number of D motifs, we identified five polymorphism groups. S. aureus 8325-4 and 91% of methicillin-resistant S. aureus (MRSA) isolates belong to polymorphism group I, with two fnb genes and three copies of the D motif. Polymorphism group II contained one fnb gene with only two D motifs and was associated with the epidemic CMRSA-4 strain, which exhibited high protease activity and low Fn binding. Polymorphism group III was unique to the epidemic CMRSA-1 strain, defined by the presence of a fourth D motif that exhibited antigenic variation within a conserved sequence that is essential for Fn binding. However, the sequence of the D motifs was otherwise highly conserved among the other polymorphism groups. Variation in Fn binding among MRSA isolates was inversely related to protease activity but not to the number of fnb genes or the number of D motifs. Therefore, the fnb locus is polymorphic in a small number of strains, but this does not contribute to variation in Fn binding. The antigenic variation that was observed only in the epidemic CMRSA-1 strain may have evolved in response to a host immune response encountered during successive cycles of colonization, transmission, and infection in the nosocomial environment.

A novel serine protease inhibition motif involving a multi-centered short hydrogen bonding network at the active site

We describe a new serine protease inhibition motif in which binding is mediated by a cluster of very short hydrogen bonds (<2.3 A) at the active site. This protease-inhibitor binding paradigm is observed at high resolution in a large set of crystal structures of trypsin, thrombin, and urokinase-type plasminogen activator (uPA) bound with a series of small molecule inhibitors (2-(2-phenol)indoles and 2-(2-phenol)benzimidazoles). In each complex there are eight enzyme-inhibitor or enzyme-water-inhibitor hydrogen bonds at the active site, three of which are very short. These short hydrogen bonds connect a triangle of oxygen atoms comprising O(gamma)(Ser195), a water molecule co-bound in the oxyanion hole (H(2)O(oxy)), and the phenolate oxygen atom of the inhibitor (O6'). Two of the other hydrogen bonds between the inhibitor and active site of the trypsin and uPA complexes become short in the thrombin counterparts, extending the three-centered short hydrogen-bonding array into a tetrahedral array of atoms (three oxygen and one nitrogen) involved in short hydrogen bonds. In the uPA complexes, the extensive hydrogen-bonding interactions at the active site prevent the inhibitor S1 amidine from forming direct hydrogen bonds with Asp189 because the S1 site is deeper in uPA than in trypsin or thrombin. Ionization equilibria at the active site associated with inhibitor binding are probed through determination and comparison of structures over a wide range of pH (3.5 to 11.4) of thrombin complexes and of trypsin complexes in three different crystal forms. The high-pH trypsin-inhibitor structures suggest that His57 is protonated at pH values as high as 9.5. The pH-dependent inhibition of trypsin, thrombin, uPA and factor Xa by 2-(2-phenol)benzimidazole analogs in which the pK(a) of the phenol group is modulated is shown to be consistent with a binding process involving ionization of both the inhibitor and the enzyme. These data further suggest that the pK(a) of His57 of each protease in the unbound state in solution is about the same, approximately 6.8. By comparing inhibition constants (K(i) values), inhibitor solubilities, inhibitor conformational energies and corresponding structures of short and normal hydrogen bond-mediated complexes, we have estimated the contribution of the short hydrogen bond networks to inhibitor affinity ( approximately 1.7 kcal/mol). The structures and K(i) values associated with the short hydrogen-bonding motif are compared with those corresponding to an alternate, Zn(2+)-mediated inhibition motif at the active site. Structural differences among apo-enzymes, enzyme-inhibitor and enzyme-inhibitor-Zn(2+) complexes are discussed in the context of affinity determinants, selectivity development, and structure-based inhibitor design.

Pseudoarrythmia from evoked potential monitoring

Somatosensory Evoked Potentials (SSEP) are used frequently in spinal instrumentation cases. In this report, we describe electrocardiographic artifacts from SSEP monitoring and offer a new explanation of the etiology.

Evaluation of four methods of flexor tendon repair for postoperative active mobilization

Active mobilization of repaired flexor tendons requires sufficient suture strength. This study was designed to investigate the suitability of four newly developed and comparatively strong tendon sutures for flexor tendon repair with active digital mobilization. Fifty fresh flexor digitorum profundus tendons were randomly assigned to five groups and repaired using the Tang, cruciate, Robertson, Silfverskiold, and modified Kessler suture methods. The repaired tendons were subjected to mechanical testing in an Instron tensile machine to determine the 2-mm gap formation force, ultimate strength, elastic modulus, and energy to failure of the sutures. The 2-mm gap formation forces of the sutures were 43.0 N for the Tang, 37.4 N for the cruciate, 25.0 N for the Robertson, 32.3 N for the Silfverskiold, and 21.2 N for the modified Kessler methods. The ultimate strength of the sutures was 53.6 N for the Tang, 46.3 N for the cruciate, 41.6 N for the Robertson, 41.0 N for the Silfverskiold, and 24.7 N for the modified Kessler methods. Statistically, the gap formation force and ultimate strength were the highest in the Tang, higher in the cruciate, and the lowest for the Robertson and the modified Kessler methods. The elastic modulus of the repaired tendons, as represented by the linear slope of the force-displacement curve, was also statistically the largest in the Tang, larger in the cruciate, and lowest for the Robertson and modified Kessler methods. Energy to failure was statistically the largest in the Tang, higher in the cruciate, lower in the Silfverskiold and the Robertson, and the lowest for the modified Kessler methods. It was concluded that significant differences exist in mechanical properties of the newly developed tendon suture methods. Among the methods for tendon repair that were tested, the Tang and the cruciate sutures were the best candidates for flexor tendon repair in the hand with postoperative active mobilization because of their superior tensile strength, elastic properties, energy to failure, and reasonable operation time.

A SNP resource for human chromosome 22: extracting dense clusters of SNPs from the genomic sequence

The recent publication of the complete sequence of human chromosome 22 provides a platform from which to investigate genomic sequence variation. We report the identification and characterization of 12,267 potential variants (SNPs and other small insertions/deletions) of human chromosome 22, discovered in the overlaps of 460 clones used for the chromosome sequencing. We found, on average, 1 potential variant every 1.07 kb and approximately 18% of the potential variants involve insertions/deletions. The SNPs have been positioned both relative to each other, and to genes, predicted genes, repeat sequences, other genetic markers, and the 2730 SNPs previously identified on the chromosome. A subset of the SNPs were verified experimentally using either PCR-RFLP or genomic Invader assays. These experiments confirmed 92% of the potential variants in a panel of 92 individuals. [Details of the SNPs and RFLP assays can be found at http://www.sanger.ac.uk and in dbSNP.]

Description of staphylococcus serine protease (ssp) operon in Staphylococcus aureus and nonpolar inactivation of sspA-encoded serine protease

Signature tagged mutagenesis has recently revealed that the Ssp serine protease (V8 protease) contributes to in vivo growth and survival of Staphylococcus aureus in different infection models, and our previous work indicated that Ssp could play a role in controlling microbial adhesion. In this study, we describe an operon structure within the ssp locus of S. aureus RN6390. The ssp gene encoding V8 protease is designated as sspA, and is followed by sspB, which encodes a 40.6-kDa cysteine protease, and sspC, which encodes a 12.9-kDa protein of unknown function. S. aureus SP6391 is an isogenic derivative of RN6390, in which specific loss of SspA function was achieved through a nonpolar allelic replacement mutation. In addition to losing SspA, the culture supernatant of SP6391 showed a loss of 22- to 23-kDa proteins and the appearance of a 40-kDa protein corresponding to SspB. Although the 40-kDa SspB protein could degrade denatured collagen, our data establish that this is a precursor form which is normally processed by SspA to form a mature cysteine protease. Culture supernatant of SP6391 also showed a new 42-kDa glucosaminidase and enhanced glucosaminidase activity in the 29 to 32 kDa range. Although nonpolar inactivation of sspA exerted a pleiotropic effect, S. aureus SP6391 exhibited enhanced virulence in a tissue abscess infection model relative to RN6390. Therefore, we conclude that SspA is required for maturation of SspB and plays a role in controlling autolytic activity but does not by itself exert a significant contribution to the development of tissue abscess infections.

Multiple advantages of alpha-fetoprotein as a marker for in vivo gene transfer

The development of improved gene transfer vectors has been hampered by the lack of a nonimmunogenic reporter gene that can be serially quantified in the serum or from other sites. In response to the need to develop a new reporter protein, we have evaluated alpha-fetoprotein (AFP) as a potential candidate. A first-generation E1/E3-deleted adenoviral vector expressing human AFP (hAFP) was generated as a preliminary tool to evaluate AFP as a reporter. Using both mouse and baboon models, hAFP expression was evaluated in serum after intravenous delivery and in serum and bronchioalveolar lavage (BAL) fluid after delivery to the lung. In immunocompetent animals, intravenous delivery of the hAFP adenoviral vector resulted in hAFP expression in the serum early after injection, which declined rapidly over time. Disappearance of hAFP from the serum was complete by 3-4 weeks after administration and was accompanied by robust antibody responses to hAFP and loss of infected cells. After lung delivery, hAFP could be detected in both serum and BAL. This allowed the analysis of the kinetics of gene expression in the lung without sacrificing the animals. In both liver and lung, immunohistochemical analysis correlated well with hAFP levels as detected in serum or BAL, indicating that serum levels were a reliable marker of tissue expression. Preliminary results with a mouse AFP expressed in a helper-dependent adenoviral vector indicate that use of a species-specific version of AFP will eliminate the complication of antibody development. These initial evaluations suggest that AFP is useful as a reporter gene to evaluate gene expression of therapeutic cassettes in multiple tissues, and it should be considered for use in human subjects.

Diagnosis of venous thromboembolism. Step-by-step approach to a still lethal disease

Rapid diagnosis of VTE is vital in reducing the significant morbidity and mortality rates associated with this disease. Although angiographic studies remain the "gold standard" for diagnosis, many noninvasive diagnostic procedures are available and are appropriate for evaluation in clinically stable patients. The algorithm presented in this article facilitates the practical and efficient use of available resources in diagnosing and treating VTE.

Prostate adenocarcinoma cells release the novel proinflammatory polypeptide EMAP-II in response to stress

The proinflammatory protein endothelial monocyte-activating polypeptide II (EMAP-II) was first detected in supernatants of murine tumor cells by virtue of its ability to stimulate endothelial-dependent coagulation in vitro. The purified protein has pleiotropic effects on endothelial cells, monocytes, and neutrophils; however, its function in vivo is unknown, and the mechanism whereby it is released from cells is poorly understood. We investigated the expression of EMAP-II in human prostate adenocarcinoma specimens by immunohistochemistry and in LNCaP and DU-145 human prostate adenocarcinoma cells by reverse transcription-PCR, flow cytometry, and Western blotting. We then examined the effects of chemical and physiological stress on release and processing of EMAP-II by LNCaP and DU-145 cells. These cells constitutively express a Mr 34,000 form of EMAP-II that is retained intracellularly. Exposure to agents that induce apoptosis or, in some cases, necrosis induces the release of the Mr 34,000 form and further processing to the Mr 27,000 and Mr 22,000 forms. Hypoxia, but not heat shock, is a potent inducer of release and processing of biologically active EMAP-II by LNCaP and DU-145 cells. We suggest that release of EMAP-II by prostate adenocarcinoma cells as a consequence of treatment with anticancer agents or as a result of constitutive hypoxia may potentiate the effects of those agents through the localized activation of host effector mechanisms.

Epidemiology of herpesvirus papio infection in a large captive baboon colony: similarities to Epstein-Barr virus infection in humans

The epidemiology of herpesvirus papio, a lymphocryptovirus similar to Epstein-Barr virus (EBV), was studied in a captive colony of >1900 baboons. Herpesvirus papio IgG antibody titers were measured by IFA. In total, 438 specimens from 296 baboons were assessed, including 116 serial specimens from 52 juveniles and 6 infants studied monthly for 1 year following birth and at age 18 months. Maternally derived antibody reached a nadir at 4 months of age. About 75% of animals at 12 months of age and >95% of animals after age 24 months demonstrated serologic evidence of herpesvirus papio infection. After age 3 years, the geometric mean titer was 1:60-75. The epidemiology of herpesvirus papio infection in baboons closely parallels that of EBV infection in humans. An animal model of lymphocryptovirus infection will facilitate investigations of human lymphocryptovirus biology.