Post-Progression Survival (PPS) and Overall Survival (OS) According to Treatment Type in Contemporary Phase III Trials in Advanced Breast Cancer (ABC)

Objective: Progression-free survival (PFS) and time to tumor progression (TTP) have been the most frequent primary endpoints in recent phase III trials in ABC. OS, the most frequent secondary endpoint (Katz ASCO 2009), is largely influenced by subsequent-line therapy, and the role of PFS/TTP as surrogates for OS is still uncertain, perhaps due to the influence of post-progression therapy. Thus, PPS is of interest as a determinant of OS, and may vary according to treatment type.Methods: Using the medical subject headings “breast neoplasms” and “drug therapy”, we searched PubMed for phase III trials on systemic antineoplastic therapies published between January 1, 1998, and December 31, 2007 in one of 11 leading medical journals (Ann Oncol, BCRT, Br J Cancer, Cancer, Clin Cancer Res, Eur J Cancer, JCO, JNCI, Lancet Oncol, Lancet and NEJM). We excluded trials with factorial design, studies on high-dose chemotherapy, papers reporting combined analyses of two or more trials, and companion studies on correlative biology or prognostic factors. PPS was calculated as median OS minus median PFS/TTP for each trial arm. The proportion of OS accounted for by PPS (PPS%OS) was calculated as 100 - [median PFS/TTP/median OS]% for each trial arm.Results: The search yielded 75 trials enrolling a total of 28,973 evaluable patients in 159 trial arms. The following table displays the results, considering trial arms with available medians for both PFS/TTP and OS. PPS%OS is larger in hormone-therapy trials than in chemotherapy trials (P<0.01). Overall, PPS has a stronger correlation with OS than do PFS/TTP (R-squares of 0.83 and 0.24, respectively; both P<0.01), at least in part because PPS is longer than PFS/TTP.Main results  Mean ofmedians(months) Trial typeN armsPFS/TTPOSPPSMedian PPS%OSOVERALL1276.920.513.665.7%1. Chemotherapy96718.311.463.7%1.1 Chemo 1st line only597.820.712.964.4%1.2 Chemo 2nd line only146.715.28.559.8%1.3 Other (mixed lines)235.014.19.164.4%2. Hormone therapy296.927.420.574.4%2.1 Hormone 1st line only139.331.121.869.0%2.2 Hormone 2nd line only135.023.218.177.9% Conclusion: The contemporary average median OS in ABC is 20.7 months for first-line chemotherapy ± targeted agents and 31.1 months for first-line hormone therapy ± chemotherapy trials. Subsequent lines of therapy play a major role in determining OS in ABC, and further studies are needed to understand the role of PFS/TTP versus PPS in determining OS, since first-line PFS/TTP have not been convincingly shown to be good surrogates for OS in the literature on ABC.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5116.

Subgroup Analyses in Contemporary Phase III Trials in Advanced Breast Cancer (ABC)

Objective: Subgroup analyses of treatment effects according to baseline patient characteristics are often performed in phase III trials in oncology. However, the frequency and determinants of this practice in ABC have not been described in the literature.Methods: We used the medical subject headings “breast neoplasms” and “drug therapy” to search PubMed for phase III trials on systemic antineoplastic therapies published between 01/00 and 12/07 in one of 10 leading medical journals (Ann Oncol, BCRT, Br J Cancer, Cancer, Eur J Cancer, JCO, JNCI, Lancet Oncol, Lancet and NEJM). We excluded factorial trials and studies on high-dose chemotherapy. When a subgroup analysis was not reported in the main article for each trial, a PubMed search was conducted using the names of first and last authors (separately) and the experimental drug(s). All variables were analyzed as reported by the authors of trials.Results: The initial search yielded 58 trials enrolling a total of 23,371 patients in 122 trial arms. For 31 trials (53.4%), a subgroup analysis was reported in the main article. Another 7 trials reported a subgroup analysis in a companion paper, for a total of 38 out of 58 trials reporting a subgroup analysis (65.5%; 95% CI, 51.8 – 77.2%). Such analyses were reportedly pre-planned in only 11/38 cases (28.9%), and only two trials reported a formal test for interaction. The number of factors considered in subgroup analyses ranged from 1 to 14. In 21/38 cases (55.3%), none of these factors was used for stratification before randomization. The results of the subgroup analysis were mentioned in the main article abstract in 13/31 cases (41.9%), 5 of which in the conclusions. There was no difference in the proportion of positive (70.4%) and negative (61.3%) trials (regarding their primary endpoints) for which a subgroup analysis was reported (P=0.53). Likewise, financial support (pharmaceutical industry [N=36] vs others [N=22]) was not predictive of subgroup analysis (P=0.17). However, trials published between 2000 and 2003 were more likely (P=0.03) to report a subgroup analysis (79.3%) than trials published between 2004 and 2007 (51.7%).Conclusion: Our review suggests that subgroup analyses are frequently performed in phase III trials in ABC. In the vast majority of cases, no formal test for interaction is presented. There seems to be a temporal trend for decrease in reporting of subgroup analyses. Other potential predictors of subgroup analysis are currently being sought.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2107.

Three-dimensional structure of the enveloped bacteriophage phi12: an incomplete T = 13 lattice is superposed on an enclosed T = 1 shell

Background

Bacteriophage φ12 is a member of the Cystoviridae, a unique group of lipid containing membrane enveloped bacteriophages that infect the bacterial plant pathogen Pseudomonas syringae pv. phaseolicola. The genomes of the virus species contain three double-stranded (dsRNA) segments, and the virus capsid itself is organized in multiple protein shells. The segmented dsRNA genome, the multi-layered arrangement of the capsid and the overall viral replication scheme make the Cystoviridae similar to the Reoviridae.

Methodology/Principal Findings

We present structural studies of cystovirus φ12 obtained using cryo-electron microscopy and image processing techniques. We have collected images of isolated φ12 virions and generated reconstructions of both the entire particles and the polymerase complex (PC). We find that in the nucleocapsid (NC), the φ12 P8 protein is organized on an incomplete T = 13 icosahedral lattice where the symmetry axes of the T = 13 layer and the enclosed T = 1 layer of the PC superpose. This is the same general protein-component organization found in φ6 NC's but the detailed structure of the entire φ12 P8 layer is distinct from that found in the best classified cystovirus species φ6. In the reconstruction of the NC, the P8 layer includes protein density surrounding the hexamers of P4 that sit at the 5-fold vertices of the icosahedral lattice. We believe these novel features correspond to dimers of protein P7.

Conclusions/Significance

In conclusion, we have determined that the φ12 NC surface is composed of an incomplete T = 13 P8 layer forming a net-like configuration. The significance of this finding in regard to cystovirus assembly is that vacancies in the lattice could have the potential to accommodate additional viral proteins that are required for RNA packaging and synthesis.

Overall survival (OS) in contemporary randomized clinical trials (RCT) in advanced breast cancer (ABC)

1002

Background: OS has been considered an elusive endpoint, while progression-free survival (PFS), time to tumor progression (TTP), and time to treatment failure (TTF) have been used frequently and often interchangeably as primary endpoints (PE) in ABC (Saad, Ann Oncol 2009). Methods: We searched PubMed using the medical subject headings “breast neoplasms” and “drug therapy,” limiting the search to phase III trials on systemic antineoplastic therapies published between 1/2000 and 12/2007 in 8 leading medical journals (Ann Oncol, BCRT, BJC, Cancer, EJC, JCO, Lancet Oncol, and NEJM). PE was the one stated explicitly, used for N calculation, or listed first. Significant PE (SigPE) was considered as P <0.05 for superiority trials (N=47), or proven non-inferiority/equivalence otherwise. Results: We retrieved 58 RTCs, with a median sample size of 329 evaluable patients. The table shows the breakdown of these trials by size and PE, and the number of trials that reached statistical significance on their PE and on OS. Overall, a statistically significant gain in OS was reported in 11 of 58 RCTs (19%). In 30 RCTs with gain in PE, 26 favored the experimental arm. Conclusions: While publication and journal selection biases may not be excluded, our review suggests that gain in OS, although seldom a primary study objective, is not infrequent in contemporary RCTs in ABC. However, the majority of RCTs are underpowered for OS, which remains a secondary or exploratory endpoint in most cases.

[Table: see text]

No significant financial relationships to disclose.

Is there consensus in the definition of endpoints in metastatic breast cancer?

Abstract #3102

Objective: Progression-free survival (PFS) is defined as the time between treatment initiation and tumor progression or death from any cause, with censoring of patients who are lost to follow-up. Time to tumor progression (TTP) is theoretically different from PFS in that the event of interest is only disease progression. Both PFS and TTP have been considered as appropriate endpoints in drug development, but the extent to which investigators agree on their definition is unknown. We therefore assessed the recent literature regarding the consistence of the definition of PFS and TTP when used as primary endpoints in advanced breast cancer.&#x2028; Methods: We searched PubMed using the medical subject headings “breast neoplasms” and “drug therapy”, limiting the search to phase III trials on systemic antineoplastic therapies published between January 1, 2000, and December 31, 2007 in one of ten leading medical journals in the field (Annals of Oncology, Breast Cancer Research and Treatment, British Journal of Cancer, Cancer, European Journal of Cancer, Journal of Clinical Oncology, Journal of the National Cancer Institute, Lancet Oncology, The Lancet and The New England Journal of Medicine). We excluded randomized phase II trials, factorial trials, studies on high-dose chemotherapy, papers reporting combined analyses of two or more separate trials, and companion studies on correlative biology or prognostic factors.&#x2028; Results: The search yielded 59 trials enrolling a total of 23,371 evaluable patients in 122 treatment arms. PFS was the primary endpoint in 14 cases, and TTP in 21 when all treatment lines and modalities were considered (response rate was used in 20 cases, and overall survival in only one). For first-line chemotherapy trials (N=24), PFS and TTP were used as primary endpoints in 5 and 7 cases, respectively. In 5 of the 21 trials using TTP as the primary endpoint, no definition of this endpoint was reported in the article. Analysis of the other 16 cases showed that progressive disease was always considered an event in TTP analysis. However, in 13 of these cases, death (either from breast cancer or from any cause) was also counted as an event. The definition of PFS was reported in the article in 13 of the 14 trials using this primary endpoint. In all cases, the events of interest in Kaplan-Meier analyses included both progressive disease and death. In some cases, both terms (PFS and TTP) were even used to denote the same endpoint in the same paper.&#x2028; Conclusion: Our review suggests that investigators are frequently using PFS and TTP interchangeably in metastatic breast cancer. Such use of terms may lead to confusion when results of different trials are evaluated in perspective, and standardization of the definitions seems therefore in order.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3102.

Progression-free survival and time to progression as primary end points in advanced breast cancer: often used, sometimes loosely defined

BACKGROUND

The growing availability of active agents makes the development of novel therapies increasingly complex and the choice of end points critical. We assessed the frequency of use of efficacy end points in advanced breast cancer.

METHODS

We searched PubMed for randomized trials published between 2000 and 2007 in 10 leading medical journals. We abstracted data on progression-free survival (PFS), time to tumor progression (TTP), response rate (RR) and overall survival.

RESULTS

A total of 58 studies enrolled 23,371 assessable patients in 122 treatment arms. The primary end points most frequently used were RR and TTP (n=21 each), followed by PFS (n=14). In five of the trials using TTP as the primary end point, no definition of TTP was reported; in 13 of the other 16 cases, death was counted as an event, making TTP indistinguishable from PFS. Trials having PFS, TTP or time to treatment failure as the primary end point (n=36) had a higher mean number of patients than those using RR (P=0.061).

CONCLUSION

Investigators seem to be frequently using PFS and TTP interchangeably in advanced breast cancer. Such use of terms may lead to confusion when results of different trials are compared, and uniform use of definitions seems in order.

Improved orthodontic stainless steel wires coated with inorganic fullerene-like nanoparticles of WS(2) impregnated in electroless nickel-phosphorous film

OBJECTIVE

To reduce friction between orthodontic stainless wires and bracket by coating the wire with nickel-phosphorous electroless film impregnated with inorganic fullerene-like nanoparticles of tungsten disulfide (IF-WS(2)) which are potent dry lubricants.

METHODS

Coating was preformed by inserting stainless steel (SS) wires into electroless solutions of nickel-phosphorus (Ni-P) and IF-WS(2). The coated wires were analyzed by SEM (scanning electron microscope) and EDS (energy-dispersive X-ray spectrometer) as well as by tribological tests using a ball-on-flat device. Friction tests simulating archwire functioning of the coated and uncoated wires were carried out by an Instron machine. The adhesion properties of the coated wires after friction were analyzed by a Raman microscope.

RESULTS

SEM/EDS analysis of the coated wires showed clear impregnation of the IF-WS(2) nanoparticles in the Ni-P matrix. The friction coefficient measured by the ball-on-flat tribometer was significantly reduced (from 0.25 to 0.08). The friction forces as measured with the Instron on the coated wire were reduced by up to 54% (4.00 N+/-0.19 uncoated vs. 1.85 N+/-0.21 coated). Raman spectra showed that even after extensive friction tests the Ni-P with the IF-WS(2) nanoparticles is attached to the underlying stainless steel wire.

CONCLUSIONS

It is proposed that the wires coated with these nanoparticles might offer a novel opportunity to substantially reduce friction during tooth movement. A few tests undertaken to evaluate the toxicity of the fullerene-like nanoparticles have provided indications that they might be biocompatible.

Activation of glucose transport and AMP-activated protein kinase during muscle contraction in adenylate kinase-1 knockout mice

AIM

Recently it was reported that adenylate kinase-1 knockout mice (AK(-/-)) exhibit elevated rates of glucose uptake following repeated contractions and hypoxia, but the mechanism was not investigated. The purpose of the present study was to measure the changes in glucose transport and AMP-activated protein kinase (AMPK) phosphorylation/activity following repeated contractions in isolated muscles from AK(-/-) mice.

METHODS

Extensor digitorum longus muscles underwent an intense stimulation protocol that decreased force to less than 10% of initial by the end of 10 min. Glucose uptake was measured with 2-deoxy-D-[1,2-(3)H]glucose.

RESULTS

Muscle glucose uptake in the basal state was identical between control and AK(-/-) mice and increased twofold in both groups during contraction. The general antioxidant: N-acetylcysteine, decreased contraction-mediated glucose uptake by 30% in both groups. AMPK activity and phosphorylation were similar in the two groups in the basal state and, surprisingly, after contraction as well (approximately threefold increase). Both groups exhibited marked decreases in adenosine triphosphate following contraction (60-70% depletion), which coincided with stoichiometric increases in the content of inosine monophosphate, an indirect marker of AMP production. Adenylate kinase activity averaged 2081 +/- 106 micromol min(-1) (g dry wt)(-1) for control and 37 +/- 10 for AK(-/-) muscles; the activity in the AK(-/-) muscle is likely accounted for by isoforms other than AK1.

CONCLUSION

In conclusion, AK(-/-) mice have a normal capacity for contraction-mediated glucose uptake. This appears to occur via increases in AMP and reactive oxygen species that result in the activation of AMPK.

Corticosterone oxidative neutralization by 11-beta hydroxysteroid dehydrogenases in kidney and colon of the domestic fowl

In mammalian organs involved in sodium reabsorption, the 11-beta hydroxysteroid dehydrogenases (11betaHSDs) oxidize glucocorticoids (GC) from their 11-alcohol form to their 11-keto state and therefore prevent their binding to mineralocorticoid (MC) receptors (MR) and the development of a MC excess syndrome. In birds the information about 11betaHSDs and GC metabolism in such organs is scarce. Herein, we report the expression and enzymatic activity of 11betaHSDs in the kidney and colon of chickens. Both organs express 11betaHSD2-like mRNA. With NAD(+), microsomes from both tissues oxidized corticosterone (CS) into 11-dehydrocorticosterone (DHC) with K(m) of 200 and 20nM and V(max) of 13 and 2pmol/mg protein/min in the kidney and colon, respectively. Thiram, a specific 11betaHSD2 inhibitor, suppressed this oxidation in kidney. The expression and action of the putative 11betaHSD3 were also tested. The chicken colon, and to a greater extent the kidney, expressed 11betaHSD3-like mRNA. Microsomal fractions from both tissues oxidized CS into DHC in the presence of NADP(+) with K(m) of 150 and 4nM and V(max) of 5 and 0.3pmol/mg protein/min for the kidney and the colon, respectively. This oxidation was not affected when NADP(+) conversion into NAD(+) was inhibited by excess pyrophosphate or a phosphatase inhibitor cocktail. In microsomes of chicken's duodenum, where 11betaHSD1-like mRNA expression is high, NADP(+)-dependent oxidation of CS into DHC has a low-affinity K(m) of 1130nM. This study documented the expression and activity of two enzymes that convert CS into DHC, one is 11betaHSD2-like and the other is similar to the putative mammalian 11betaHSD3.

Distinct features of dehydrocorticosterone reduction into corticosterone in the liver and duodenum of the domestic fowl (Gallus gallus domesticus)

The mammalian 11-beta hydroxysteroid dehydrogenase type 1 (11 betaHSD1) reduces glucocorticoids (GC) at C11 from the 11-keto-GC nonactive form to the 11-hydroxy-GC active form, an action essential for survival. Whereas GC metabolism at C11 and the role of 11 betaHSD1 are studied extensively in mammals, information about these in birds is scattered. Herein, we report the GC bidirectional metabolism in chickens. In hens' liver and duodenal mucosa, 11 betaHSD1-like mRNA expression was detected; and 11 betaHSD1-like immunoreactivity was found linked to membranes of hepatocytes and duodenal enterocytes. With either NADH or NADPH, the membranal fraction of liver and duodenal mucosa converted dehydrocorticosterone (A) into corticosterone (B) with K(m) (1.1-8.7 microM) and V(max) (10-40 pmol/mg protein/min) values similar to those reported for mammalian 11 betaHSD1. In the presence of NADP(+) or NAD(+), these membranal fractions oxidized B into A. With either NADPH or NADH, the cytosol of chicken liver and duodenal mucosa reduced A into B (K(m) of 1.1 - 2.3 microM and V(max) of 260-960 pmol/mg protein/min). These cytosolic fractions did not convert any amount of B into A when incubated with either NADP(+) or NAD(+). This may suggest that chicken liver and duodenal mucosa express 11 betaHSD1 that is a membrane-bound oxoreductase which uses both NADPH/NADP(+) and NADH/NAD(+) as cosubstrates. The substantial reduction of A into B (but no conversion of B into A) found in the cytosol is most likely executed by a unidirectional soluble reductase, different than 11 betaHSD1.

Phase II trial of high dose imatinib in recurrent glioblastoma multiforme (GBM) with platelet derived growth factor receptor (PDGFR) expression

2056

Background: GBM are the most common primary brain tumors in adults. Despite available treatment they carry a poor prognosis with recurrences in most patients (pts) after initial therapy. PDGF signaling has been postulated to play a role in GBM transformation. We have demonstrated that PDGFRβ is expressed in tumor cells in 50% and in peritumoral endothelial cells in 65% of GBM (Barrios et al, abstract 11518, Proc ASCO 2006). Imatinib, an inhibitor of PDGFRa/β kinase activity could have therapeutic activity in these cases. Methods: We evaluated Imatinib in pts with recurrent GBM (previous radiation and chemotherapy) selected by PDGFR expression. Analysis of PDGFRa/β was performed by standard IHC. Positivity was considered in case of any qualitative expression. Pts were treated with 800 mg/day of Imatinib until tumor progression. All were on steroids and taking enzyme inducing antiepileptic drugs. Response was determined by MRI with spectroscopy and perfusion every 8 weeks according to RECIST criteria. Results: Twenty pts were enrolled (18 GBM, 2 AA). Median age: 51 (21–74), 7 were females. ECOG-PS at inclusion: 0 (3), 1 (10), 2 (7). All pts had expression of PDGFRa and 55% expressed PDGFRβ. Response data are available for all 20 pts. Main adverse events (all grade 1–2) were: edema (55%), nausea (50%), diarrhea and fatigue (35% each). We did not observe any PR but 13 pts (65%) showed disease stabilization. Median progression-free survival was 7.8 months with 60.8% of pts alive at 6 months; 6 months PFS was 52.2%. Conclusions: Imatinib was well tolerated in this group of poor prognosis highly pre-treated GBM pts demonstrating disease stabilization in a significant proportion of cases. These results, in a limited sample, compare favorably with historical data in similar populations. Selection of pts according to the specific molecular expression of their tumor may lead to better therapeutic results.

No significant financial relationships to disclose.

Conservative management of implantable cardioverter defibrillator-related endocarditis due to Bacillus spp

Endocarditis is a devastating complication of implantable cardioverter-defibrillator (ICD) therapy. Partial or complete device removal has been advocated for the treatment of this condition although controlled data are lacking. We present a case of ICD-related endocarditis caused by Bacillus spp. that occurred following coronary angiography. To the best of our knowledge, Bacillus spp. has not been previously described in such context. Moreover, conservative treatment with device retention was successful (no recurrence during a 6-year follow-up). Conservative management may be attempted in selected cases of ICD-related endocarditis, especially, those involving low-virulence organisms and rapid response to antibiotic therapy. This case also suggests that coronary angiography may be associated with transient bacteremia and subsequent infection of indwelling cardiac devices.

Hybrid phosphorescence and fluorescence native spectroscopy for breast cancer detection

Fluorescence and phosphorescence measurements are performed on normal and malignant ex vivo human breast tissues using UV LED and xenon lamp excitation. Tryptophan (trp) phosphorescence intensity is higher in both normal glandular and adipose tissue when compared to malignant tissue. An algorithm based on the ratio of trp fluorescence intensity at 345 nm to phosphorescence intensity at 500 nm is successfully used to separate normal from malignant tissue types. Normal specimens consistently exhibited a low I(345)I(500) ratio (<10), while for malignant specimens, the I(345)I(500) ratio is consistently high (>15). The ratio analysis correlates well with histopathology. Intensity ratio maps with a spatial resolution of 0.5 mm are generated in which local regions of malignancy could be identified.

Is histology (His) relevant in adjuvant (Adj)/neoadjuvant (NA) therapy of breast cancer (BC)?

10541

Background: Invasive lobular carcinoma (ILC) constitutes 10–15% of cases of invasive BC. In ongoing NCI-sponsored, randomized trials (RT) of early BC, His is not a stratification factor, despite the suggestion that ILC might have distinct clinical behavior and gene expression profile. Compared with invasive ductal carcinoma (IDC), ILC is more frequently of lower grade and positive for estrogen receptor (ER). Methods: We reviewed the literature to evaluate the effect of His on outcome of Adj and NA therapy, by quantifying its impact on the pathologic response (pCR) rate to NA chemotherapy (CT), and on the results of adjuvant trials. We also compiled retrospective series analyzing pCR to NA CT according to His. Results: We retrieved 16 RT (8 phase III, 8 phase II) of NA therapy; 11 compared CT regimens, 3 regimens that contained CT and hormone therapy (HT), and 2 HT only. None of the RT used His for stratification; 5 studies described His at randomization, but only 1 provided information on pCR rate to CT according to His (Dieras et al, 4.0% for ILC, 8.3% for IDC). Compiled results of 6 retrospective series which included nearly 3,000 patients (PTS) showed a pCR rate of 1.7% (6 of 354) in ILC PTS and of 11.6% (300 of 2584) in IDC PTS (P < 0.01). Of 39 phase III RT of Adj CT, 7 compared CT vs HT, 14 CT vs CT + HT, 11 HT vs HT + CT, and 7 CT vs HT vs CT + HT. Of the 39 RT, only 4 described His in demography (9%, 9%, 10% and 12% of PTS participating in these 4 RT were ILC), but none analyzed results according to His. Conclusions: We suggest that the role of CT in early ILC is not clear. The pCR rate is significantly lower in ILC PTS treated with NA CT. It is also not clear if His is an independent predictive factor or a marker of grade/ER expression. The specific value of CT in the Adj treatment of ILC PTS has not been adressed in the Adj RT. Past and current, ongoing RT of Adj CT do not stratify PTS according to His neither evaluate the results according to His. Given the potential therapeutic implications, we suggest that the role of His should be more thoroughly investigated in future RT in order to define the appropriate effectiveness of CT and HT in the treatment of ILC PTS, so that possible overtreatment of ILC PTS with CT might be avoided.

No significant financial relationships to disclose.

Proteins and dipicolinic acid released during heat shock activation of Bacillus subtilis spores probed by optical spectroscopy

UV fluorescence and absorption spectroscopy from Bacillus subtilis spores detected proteins and dipicolinic acid (DPA) released into the supernatant after heat treatments ranging from 20 degrees to 90 degrees C. The protein and DPA concentration in the supernatant was greater with higher heat treatment temperatures, undergoing a substantial increase for T > or = 60 degrees C, and supporting the theory that spores undergo a phase transition from a glassylike to a rubberylike state at 56 degrees C. Gel electrophoresis detected several small proteins with molecular weights between 6 and 11 kDa. These proteins may be small acid-soluble spore proteins that are present in spores but break down during germination. A 30 kDa protein extracted above 60 degrees C is related to the rubber-glass phase transition.

Virus particles and receptor interaction monitored by fluorescence spectroscopy

Native fluorescence spectroscopy (NFS), primarily from tryptophan (trp), was used for in situ investigation of the virus-receptor attachment process in phi6, a lipid-containing bacteriophage from the Cystoviridae family. NFS allowed us to monitor the viral attachment directly to its receptor, which was isolated from the pseudomonad host. Immediately upon mixing, an increase in tryptophan emission intensity was observed followed by a subsequent decrease in emission intensity. The initial increase in emission intensity reflects changes in trp quantum efficiency as the phi6 surface proteins change their conformation as a result of virus attachment to the pilus. The cystovirus spike protein P3 is responsible for receptor recognition and the fluorescence changes observed are likely to be the consequence of its conformational transition at this initial infection stage, providing a kinetic view of this process. The subsequent decrease in trp emission intensity could be due to changes in viral proteins as a result of disassembly of the pili. The technique may have important applications for the dynamic monitoring of additional stages of the virus replication cycle such as assembly, interaction with nucleic acids and maturation. This work expands on a previous demonstration that fluorescence offered a novel tool to detect virus particle interaction with its host cell.

Wireless spectroscopic compact photonic explorer for diagnostic optical imaging

A remote, small-size spectroscopic-based device called Compact Photonics Explorer (CPE) was designed, assembled, and tested for medical and non-medical spectroscopic and imaging applications. Spatial images acquired using the spectroscopic CPE are presented. Operational principles are demonstrated for various biomedical and non-medical applications.

The feasibility of a randomised, placebo-controlled clinical trial of homeopathic treatment of depression in general practice

Depression is common in general practice and lack of concordance is an important problem in its treatment. Homeopathy has few side effects and is generally associated with good compliance. We report a study investigating the feasibility of a trial to compare the effectiveness of homeopathy with a conventional antidepressant and placebo.

OBJECTIVES

To assess the feasibility of a general practice-based clinical trial comparing the effectiveness of individualised homeopathic treatment vs Fluoxetine (Prozac) vs placebo in the treatment of major depressive episodes of moderate severity.

DESIGN

Randomised, double-dummy, double-blind parallel group clinical trial.

SETTING

Lower Clapton Group Practice, East London.

METHOD

Patients were recruited through their general practitioners as they presented during a 9 month period. Recruitment target was 30 patients. Eligibility was confirmed by a consultant psychiatrist using standard criteria (DSM-IV) and instruments Hamilton Depression Scale (HAMD). Suicidal and psychotic patients were excluded, additional precautions against suicide were incorporated. There was a 1 week run-in period and patients showing spontaneous improvement were excluded. Homeopathic treatment was prescribed by a GP qualified in homeopathy, from a 'limited list' of 30 homeopathic medicines, with the help of decision support software. Patients were randomised to receive verum Fluoxetine and placebo homeopathy, or verum homeopathy and placebo Fluoxetine, or placebo homeopathy and placebo Fluoxetine. Treatment duration was 12 weeks. The outcomes were: adverse drug reactions, clinical global impression (CGI); HAMD; mini international psychiatric Interview; Pittsburgh sleep quality index; Side-effects checklist; Short Form 12; treatment credibility questionnaire; work and social disability scale. The primary outcome measures were HAMD and CGI.

RESULTS

A recruitment calculation indicated that over 230 suitable patients would be expected to attend the practice during the recruitment phase. Thirty one patients were referred for possible inclusion in the trial by their GPs. Twenty three met the entry criteria, 11 were randomised and 6 completed the study. Of the completers, one received homeopathy, 2 placebo and 3 Fluoxetine.

CONCLUSIONS

A trial of this design in general practice is not feasible, because of recruitment difficulties, many of them linked to patient preference. Different approaches are required to recruit adequate patient numbers to trials of this sort.

In situ determination of refractive index and size of Bacillus spores by light transmission

Light-extinction measurements in the wavelength range of 400 to 1000 nm are performed in situ on Bacillus subtilis endospores during heat-shock-induced activation. Simultaneous information on particle size and refractive indices during activation is calculated from the transmission spectra by use of the Gaussian ray approximation of anomalous diffraction theory. During activation the refractive index of the core decreases from 1.51 to 1.39, and the size increases from 0.38 to 0.6 microm.

Virus particles monitored by fluorescence spectroscopy: a potential detection assay for macromolecular assembly

Native fluorescence spectroscopy was used for in situ investigations of two lipid-containing bacteriophages from the cystovirus family as well as their Pseudomonad host cells. Both the viruses phi6 and phi12 and their bacterial host proteins contain the amino acid tryptophan (trp), which is the predominant fluorophore in UV. Within proteins, trp's structural environment differs, and the differences are reflected in their spectroscopic signatures. It was observed that the peak of the trp emission from both viruses was at 330 nm, a significantly shorter wavelength than trp in either the Pseudomonad host cells or the amino acid's chemical form. This allowed us to monitor the viral attachment process and subsequent lytic release of progeny virus particles by measurement of the trp emission spectra during the infection process. This work demonstrates that fluorescence may offer a novel tool to detect viruses and monitor viral infection of cells and may be part of a biodefense application.

Acute mastoiditis in infancy: the Soroka experience: 1990-2000

Acute mastoiditis (AM) is an uncommon but serious complication of acute otitis media (AOM). In the pre-antibiotic era, AM was seen more frequently than it is today, but it was rare in infants. However, in the last two decades an increase in the incidence of AM in infancy has been reported in the literature. During the years 1990-2002, we treated 113 patients with 128 episodes of AM; of them, 24 were infants (median age 6 months; 18 males) who suffered from 26 episodes of AM. Twenty developed AM as a complication of their first episode of AOM. One of the four infants with a prior history of AOM suffered from common variable immunodeficiency. A significant increase in the incidence of AM in infants was recorded during the study period (P = 0.01). The most common presenting clinical signs were post-auricular swelling and fever >38 degrees C (77% and 77%, respectively, of all patients). Seventeen episodes of AM were not treated with prior antibiotics. Tympanocentesis was performed in all episodes of AM. Middle ear fluid culture was positive in 17 (65%) of the 26 AM episodes. The most common pathogens cultured were Streptococcus pneumoniae (10 infants, 58% of all pathogens, 3/10 intermediately susceptible to penicillin) followed by Streptococcus pyogenes (4, 23%), non-typable H. influenzae (2, 12%) and S. aureus (1, 6%). Temporal bone CT showed bone destruction in 14 patients; 3 infants had subperiosteal abscesses and 3 lateral sinus thrombosis. Ten infants underwent mastoid surgery due to non-resolution of symptoms and signs with antibiotic therapy. Eight underwent cortical mastoidectomy with two patients undergoing ventilation tube introduction only. The remainder of the infants healed with conservative treatment.

CONCLUSIONS

(1) A significant increase in the incidence of AM in infants was recorded over the last decade, though a specific reason for this trend remains uncertain; (2) Most of the cases of AM followed the infant's initial AOM episode, and most of the infants had not received prior antibiotic therapy; (3) The clinical signs and symptoms of AM were more severe in infants than in older patients; (4) While S. pneumonia was the most common pathogen isolated in middle ear fluid cultures, the involvement of S. pyogenes in AM was higher than that reported in AOM.