The Boltzmann project

The International Committee for Weights and Measures (CIPM), at its meeting in October 2017, followed the recommendation of the Consultative Committee for Units (CCU) on the redefinition of the kilogram, ampere, kelvin and mole. For the redefinition of the kelvin, the Boltzmann constant will be fixed with the numerical value 1.380 649 × 10-23 J K-1. The relative standard uncertainty to be transferred to the thermodynamic temperature value of the triple point of water will be 3.7 × 10-7, corresponding to an uncertainty in temperature of 0.10 mK, sufficiently low for all practical purposes. With the redefinition of the kelvin, the broad research activities of the temperature community on the determination of the Boltzmann constant have been very successfully completed. In the following, a review of the determinations of the Boltzmann constant k, important for the new definition of the kelvin and performed in the last decade, is given.

Primary care REFerral for EchocaRdiogram (REFER) in heart failure: a diagnostic accuracy study

BACKGROUND

Symptoms of breathlessness, fatigue, and ankle swelling are common in general practice but deciding which patients are likely to have heart failure is challenging.

AIM

To evaluate the performance of a clinical decision rule (CDR), with or without N-Terminal pro-B type natriuretic peptide (NT-proBNP) assay, for identifying heart failure.

DESIGN AND SETTING

Prospective, observational, diagnostic validation study of patients aged >55 years, presenting with shortness of breath, lethargy, or ankle oedema, from 28 general practices in England.

METHOD

The outcome was test performance of the CDR and natriuretic peptide test in determining a diagnosis of heart failure. The reference standard was an expert consensus panel of three cardiologists.

RESULTS

Three hundred and four participants were recruited, with 104 (34.2%; 95% confidence interval [CI] = 28.9 to 39.8) having a confirmed diagnosis of heart failure. The CDR+NT-proBNP had a sensitivity of 90.4% (95% CI = 83.0 to 95.3) and specificity 45.5% (95% CI = 38.5 to 52.7). NT-proBNP level alone with a cut-off <400 pg/ml had sensitivity 76.9% (95% CI = 67.6 to 84.6) and specificity 91.5% (95% CI = 86.7 to 95.0). At the lower cut-off of NT-proBNP <125 pg/ml, sensitivity was 94.2% (95% CI = 87.9 to 97.9) and specificity 49.0% (95% CI = 41.9 to 56.1).

CONCLUSION

At the low threshold of NT-proBNP <125 pg/ml, natriuretic peptide testing alone was better than a validated CDR+NT-proBNP in determining which patients presenting with symptoms went on to have a diagnosis of heart failure. The higher NT-proBNP threshold of 400 pg/ml may mean more than one in five patients with heart failure are not appropriately referred. Guideline natriuretic peptide thresholds may need to be revised.

Estimates of the difference between thermodynamic temperature and the International Temperature Scale of 1990 in the range 118 K to 303 K

Using exceptionally accurate measurements of the speed of sound in argon, we have made estimates of the difference between thermodynamic temperature, T, and the temperature estimated using the International Temperature Scale of 1990, T90, in the range 118 K to 303 K. Thermodynamic temperature was estimated using the technique of relative primary acoustic thermometry in the NPL-Cranfield combined microwave and acoustic resonator. Our values of (T-T90) agree well with most recent estimates, but because we have taken data at closely spaced temperature intervals, the data reveal previously unseen detail. Most strikingly, we see undulations in (T-T90) below 273.16 K, and the discontinuity in the slope of (T-T90) at 273.16 K appears to have the opposite sign to that previously reported.

Passive seismic experiment

Seismometer operation for 21 days at Tranquillity Base revealed, among strong signals produced by the Apollo 11 lunar module descent stage, a small proportion of probable natural seismic signals. The latter are long-duration, emergent oscillations which lack the discrete phases and coherence of earthquake signals. From similarity with the impact signal of the Apollo 12 ascent stage, they are thought to be produced by meteoroid impacts or shallow moonquakes. This signal character may imply transmission with high Q and intense wave scattering, conditions which are mutually exclusive on earth. Natural background noise is very much smaller than on earth, and lunar tectonism may be very low.

RNA segment 9 exists as a duplex concatemer in an Australian strain of epizootic haemorrhagic disease virus (EHDV): Genetic analysis and evidence for the presence of concatemers as a normal feature of orbivirus replication

This paper reports a concatemeric RNA in a strain of epizootic haemorrhagic disease virus (EHDV) serotype 5. Sequencing showed that the concatemeric RNA contains two identical full-length copies of genome segment 9, arranged in series, which has apparently replaced the monomeric form of the segment. In vitro translation demonstrated that the concatemeric RNA can act as a viable template for VP6 translation, but that no double-sized protein is produced. Studies were also performed to assess whether mutations might be easily introduced into the second copy (which might indicate some potential evolutionary significance of a concatemeric RNA segment), however multiple (n=40) passages generated no changes in the sequence of either the upstream or downstream segments. Further, we present results that demonstrate the presence of concatemers or partial gene duplications in multiple segments of different orbiviruses (in tissue culture and purified virus), suggesting their generation is likely to be a normal feature of orbivirus replication.

Sorafenib in combination with weekly topotecan in recurrent ovarian cancer, a phase I/II study of the Hoosier Oncology Group

OBJECTIVE

This trial determined the efficacy and tolerability of sorafenib and weekly topotecan in patients with platinum-resistant ovarian cancer (OC) or primary peritoneal carcinomatosis (PPC).

METHODS

Primary endpoints were maximum tolerated dose of sorafenib with weekly topotecan (phase I) and response rate (phase II). Secondary endpoints were progression free survival (PFS), overall survival (OS), toxicity, and rate of clinical benefit. Eligibility included recurrent platinum-resistant OC or PPC, <3 prior regimens, normal end-organ function. 3+3 dose escalation was used for phase I, sorafenib being tested at 400mg and 800 mg orally daily. Topotecan dose was reduced from 4 mg/m(2) to 3.5mg/m(2) IV weekly. The phase II regimen was sorafenib 400mg daily and topotecan 3.5mg/m(2) weekly on days 1, 8, 15 of a 28 days cycle.

RESULTS

16 patients were enrolled in phase I and 14 patients in phase II. Median age was 52.5 years (range 35-79), 27 patients had OC, and 3 PPC. Median number of cycles administered was 2.5 (0-15). There were 5 partial responses (PR) (16.7%), and 14 patients (46.7%) with stable disease (SD). Four PRs were recorded during phase I and 1 during phase II. One of those PRs occurred in a patient with platinum-sensitive disease. Grade 3/4 toxicities included leukopenia/neutropenia (23%), thrombocytopenia (17%), anemia (10%), fatigue, nausea, vomiting (7% each). One case of grade 3 hand-foot syndrome was recorded.

CONCLUSIONS

The combination of sorafenib and topotecan causes significant toxicity, precluding administration of full doses and resulting in modest clinical efficacy in platinum resistant OC or PPC.

Seismic data from man-made impacts on the moon

Unusually long reverberations were recorded from two lunar impacts by a seismic station installed on the lunar surface by the Apollo 12 astronauts. Seismic data from these impacts suggest that the lunar mare in the region of the Apollo 12 landing site consists of material with very low seismic velocities near the surface, with velocity increasing with depth to 5 to 6 kilometers per second (for compressional waves) at a depth of 20 kilometers. Absorption of seismic waves in this structure is extremely low relative to typical continental crustal materials on earth. It is unlikely that a major boundary similar to the crustmantle interface on earth exists in the outer 20 kilometers of the moon. A combination of dispersion and scattering of surface waves probably explains the lunar seismic reverberation. Scattering of these waves implies the presence of heterogeneity within the outer zone of the mare on a scale of from several hundred meters (or less) to several kilometers. Seismic signals from 160 events of natural origin have been recorded during the first 7 months of operation of the Apollo 12 seismic station. At least 26 of the natural events are small moonquakes. Many of the natural events are thought to be meteoroid impacts.

The viking seismic experiment

A three-axis short-period seismometer is now operating on Mars in the Utopia Planitia region. The noise background correlates well with wind gusts. Although no quakes have been detected in the first 60 days of observation, it is premature to draw any conclusions about the seismicity of Mars. The instrument is expected to return data for at least 2 years.

PRECEDENT: A randomized phase II trial comparing EC145 and pegylated liposomal doxorubicin (PLD) in combination, versus PLD alone, in subjects with platinum-resistant ovarian cancer

LBA5012b

Background: EC145, a conjugate of folic acid and desacetylvinblastine hydrazide binds with high affinity to the folate receptor (FR), found on > 90% of epithelial ovarian cancers. This abstract reports interim data on an international randomized, phase II study of EC145 + PLD compared with PLD alone, in women with platinum-resistant ovarian cancer. An independent Data Safety Monitoring Board (DSMB) has conducted a prespecified interim analysis on PFS and safety with results reported herein.

Methods: Women ≥ 18 with ECOG PS of 0-2 and ≤ 2 prior systemic cytotoxic regimens were randomized to receive EC145 (2.5 mg IV weeks 1 and 3) + PLD (50 mg/m2 IBW IV q 28 days) or PLD (50 mg/m2 IBW IV q 28 days) alone until progression or death.

Results: The interim analysis occurred after the 46th event out of a planned study total of 95 progressions or deaths. Demographic characteristics at screening such as age, cancer type, residual tumor after debulking, prior therapy, CA-125 and time from diagnosis were balanced between arms. RECIST mean sum tumor length was longer for the combination arm (122.7 mm vs. 81.3 mm). There was no statistical difference between study arms with regard to total adverse events, serious adverse events, or the number of subjects reporting at least one treatment-emergent drug-related serious adverse event resulting in discontinuation. The Table displays the results of the interim analysis of PFS. At the interim, there is also a trend toward benefit in overall survival for the combination arm with HR = 0.425 (p value of 0.064).

Conclusions: Results indicate a greater than doubling in median PFS for women with platinum-resistant ovarian cancer receiving EC145 and PLD over those receiving PLD alone. These interim data suggest that EC145 and PLD is the first combination to show a statistically significant delay in progression-free survival over standard therapy in women with platinum-resistant ovarian cancer.

[Table: see text]

[Table: see text]

The evolution of two homologues of the core protein VP6 of epizootic haemorrhagic disease virus (EHDV), which correspond to the geographical origin of the virus

Epizootic haemorrhagic disease virus is a 10-segmented, double-stranded RNA virus. When these ten segments of dsRNA are run on 1% agarose, eastern (Australia, Japan) and western (North America, Africa, Middle-East) strains of the virus can be separated phenotypically based on the migration of genome segments 7-9. In western strains, segments 7-9 are roughly the same size and co-migrate as a single RNA band. In eastern strains, segment 9 is smaller, so while segments 7 and 8 co-migrate, the segment 9 RNA runs faster than its western homologue. Translation experiments demonstrated that these two segment 9 homologues are both functional and produce proteins (VP6) of different sizes-something that has not been reported in any other orbivirus species to date. Sequence analysis suggests that eastern and western versions of segment 9 (VP6) have likely evolved as a response to adaptive selection in different geographical regions via gene duplication and subsequent mutation. These significant findings are considered unusual given the conserved nature of VP6 and its presumed role as the viral helicase. It is not currently known what the biological relevance of each homologue is to the virus.

Genetic and phylogenetic analysis of the core proteins VP1, VP3, VP4, VP6 and VP7 of epizootic haemorrhagic disease virus (EHDV)

The core proteins of epizootic haemorrhagic disease virus (EHDV) have important roles to perform in maintaining the structure and function of the virus. A complete genetic and phylogenetic analysis was therefore performed on these proteins (and the genes that code for them) to allow comparison of the selective pressures acting on each. Accession numbers, gene and protein sizes, ORF positions, G+C contents, terminal hexanucleotides, start and stop codons and phylogenetic relationships are all presented. The inner core proteins (VP1, VP3, VP4 and VP6) were characterised by high levels of sequence conservation, and the ability to topotype isolates very strongly into eastern or western groups. This is particularly evident in genome segment 9 (VP6) which exists as two different sized homologues. VP7 did not topotype, but rather exhibited a more random, radial phylogeny suggestive of genetic drift. With the exception of VP6, all of the core proteins also showed high numbers of synonymous mutations in the third base position, suggesting they have been evolving for a long period of time. Interestingly, VP6 did not show this, and possible reasons for this are discussed.

Genetic and phylogenetic analysis of the outer-coat proteins VP2 and VP5 of epizootic haemorrhagic disease virus (EHDV): comparison of genetic and serological data to characterise the EHDV serogroup

The outer-coat proteins, VP2 and VP5, of epizootic haemorrhagic disease virus (EHDV) are important for host cell binding during the initiation of infection. They are also known to determine virus serotype. This study presents a complete genetic and phylogenetic analysis of these proteins (and the genes that code for them) to allow comparison of the selective pressures acting on each and the correlation of genetic sequence data with serotype. Accession numbers, gene and protein sizes, ORF positions, G+C contents, terminal hexanucleotides, start and stop codons and phylogenetic relationships are all presented. The results show that VP2 is highly variable, is under great pressure to adapt and can be correlated with serotype. While also variable, VP5 appears to be under less adaptive pressure than VP2 but still shows some correlation with serotype. Seven serotypes of EHDV have been defined in this study, although the results do show that some serotypes are extremely closely related--and highlight the benefit of using both molecular and serologic analyses. Analysis of the terminal hexanucleotides showed that the 5' terminus is under greater purifying selection than the 3'. Evidence is also presented that both segments 2 and 6 (coding for VP2 and VP5 respectively) have grown via gene duplication and subsequent mutation.

Phase II pilot study of biweekly cisplatin and gemcitabine in multi-refractory ovarian cancer

16065

Background: Preclinical data suggest the combination of cisplatin and gemcitabine may have synergy in inhibiting ovarian cancer growth in vitro. Clinical trials in breast cancer support the use of biweekly gemcitabine. A pilot trial of biweekly cisplatin and gemcitabine in multi-refractory ovarian cancer was undertaken. Methods: This was a single-stage phase II pilot trial. Eligible patients had platinum-resistant, multidrug-refractory epithelial ovarian cancer with CA125 levels exceeding 90 units/ml and acceptable renal, hepatic, and bone marrow function. Cisplatin 30 mg/m2 IV and gemcitabine 800–1000 mg/m2 IV were given biweekly (d1, 15) and CA125 levles monitored. Toxicity was monitored before each course and graded by NCI-CTC. Responses were measured using Rustin's criteria (JCO 15:172,1997). Treatment was continued until disease progression or prohibitive toxicity supervened. Results: Eleven patients aged 30–71 years (median 58 years) with advanced ovarian cancer received cisplatin and gemcitabine. They had been treated with from 1 to 7 (mean 3.9) previous chemotherapy regimens. A total of 85 course (mean 7.7 courses/patient) were administered, Toxicity included CTC grade 2 anemia in 3 patients and one case each of grade 2 and grade 4 neutropenia without fever. No patients experienced exacerbation of pre-existing peripheral neuropathy. Two patients had stable disease of 3 months or greater duration, four (36%) had complete responses (CA125 decrease > or = to 75% baseline), and the remainder had progressive disease. Conclusions: Biweekly cisplatin and gemcitabine is an active combination in patients with refractory ovarian cancer. Limited toxicity and ease of administration suggest a role for this combination in consolidation therapy.

[Table: see text]

Eukaryotic expression: developments for structural proteomics

The production of sufficient quantities of protein is an essential prelude to a structure determination, but for many viral and human proteins this cannot be achieved using prokaryotic expression systems. Groups in the Structural Proteomics In Europe (SPINE) consortium have developed and implemented high‐throughput (HTP) methodologies for cloning, expression screening and protein production in eukaryotic systems. Studies focused on three systems: yeast (Pichia pastoris and Saccharomyces cerevisiae), baculovirus‐infected insect cells and transient expression in mammalian cells. Suitable vectors for HTP cloning are described and results from their use in expression screening and protein‐production pipelines are reported. Strategies for co‐expression, selenomethionine labelling (in all three eukaryotic systems) and control of glycosylation (for secreted proteins in mammalian cells) are assessed.

Clinical activity of imatinib mesylate in combination with docetaxel in patients with advanced, platinum-resistant ovarian cancer—Hoosier Oncology Group GYN03–62

5091

Background: Ovarian tumors harborc-Kit and PDGF receptors. We showed in an in-vitro model that Imatinib (G) inhibits the growth of ovarian cancer cells. We hypothesized that G in combination with chemotherapy inhibits the growth of ovarian tumors. Data from a phase II clinical trial utilizing G in combination with Docetaxel (D) in patients with advanced ovarian cancer (OC) are presented. Methods: This was an open label, one stage, multi-center phase II clinical trial. Planned sample size was 23. Patients with relapsed, platinum-resistant or refractory OC expressing PDGFR or c-kit were eligible. PDGFR and c-kit expression was assessed prior to enrollment by IHC using archival tumor tissue. G was administered at 600mg/d continuously and D was given weekly (30mg/m2) for 4 weeks, with 2 weeks break. Each cycle was 6 weeks, with a maximum of 6 cycles allowed. Tumor assessments were obtained after 2, 4 and 6 cycles. Response rate by RECIST was the primary endpoint. Results: 34 patients were screened. 17 tumors were c-kit + and 25 were PDGFRα +. 23 patients were enrolled. Of those, 4 patients had c-kit+/PDGFR- tumors, 12 were PDGFR+/c-kit- and 7 were c-kit+/PDGFR+. Median age was 55 (range 33–76) and median PS was 0 (range 0–2). Median number of prior treatments was 3 (range 1–9). Efficacy and toxicity data are available for 20 and 14 patients, respectively. Based on RECIST, there were 3 patients with PR and 3 patients with SD lasting at least 12 weeks. Of these 6 patients, 2 pts were c-kit+, 2 were PDGFR+ and 2 were PDGFR and c-kit+. All 6 patients had carboplatin and taxane resistant disease. Grade 3–4 toxicities were: neutropenia (2), thrombocytopenia (1), fatigue (1), dehydration (1), constipation (1), cardiac ischemia (1), nausea/vomiting (2), urinary frequency (1). Other G1–2 toxicities were: N/V (9), diarrhea (7), fatigue (8), mucositis (4), anemia (4), hypocalcemia (5), rash (6), anorexia (7), edema (5), hemolysis (1), non-neutropenic infections (7). Additional data will be available in May 2006. Conclusions: The combination G+D is tolerated well. Clinical activity consisted of 3 PRs (15% response rate) and 3 SD > 3 months in pts with heavily pre-treated, platinum resistant OC expressing c-kit or PDGFRα.

[Table: see text]

The Warfarin/Aspirin Study in Heart failure (WASH): a randomized trial comparing antithrombotic strategies for patients with heart failure

BACKGROUND

Heart failure is commonly associated with vascular disease and a high rate of athero-thrombotic events, but the risks and benefits of antithrombotic therapy are unknown.

METHODS

The current study was an open-label, randomized, controlled trial comparing no antithrombotic therapy, aspirin (300 mg/day), and warfarin (target international normalized ratio 2.5) in patients with heart failure and left ventricular systolic dysfunction requiring diuretic therapy. The primary objective was to demonstrate the feasibility and inform the design of a larger outcome study. The primary clinical outcome was death, nonfatal myocardial infarction, or nonfatal stroke.

RESULTS

Two hundred seventy-nine patients were randomized and 627 patient-years exposure were accumulated over a mean follow-up time of 27 +/- 1 months. Twenty-six (26%), 29 (32%), and 23 (26%) patients randomized to no antithrombotic treatment, aspirin, and warfarin, respectively, reached the primary outcome (ns). There were trends to a worse outcome among those randomized to aspirin for a number of secondary outcomes. Significantly (P =.044) more patients randomized to aspirin were hospitalized for cardiovascular reasons, especially worsening heart failure.

CONCLUSIONS

The Warfarin/Aspirin Study in Heart failure (WASH) provides no evidence that aspirin is effective or safe in patients with heart failure. The benefits of warfarin for patients with heart failure in sinus rhythm have not been established. Antithrombotic therapy in patients with heart failure is not evidence based but commonly contributes to polypharmacy.

Corneal replacement using a synthetic hydrogel cornea, AlphaCor: device, preliminary outcomes and complications

PURPOSE

Clinical assessment of outcome of corneal replacement with a synthetic cornea, AlphaCor, in patients considered at too high risk for conventional penetrating keratoplasty with donor tissue to be successful, but excluding indications such as end-stage dry eye that might be suited to traditional prosthokeratoplasty.

METHODS

All patients in the multicentre clinical trial were managed according to an approved protocol, with Ethics Committee approval in each centre. Preoperative visual acuity ranged from perception of light (PL) to 6/60 (20/200). Implantation was by means of an intralamellar technique, with a conjunctival flap in most cases. Tissues anterior to the optic were removed as a secondary procedure.

RESULTS

Up to 30 November 2001, 40 AlphaCor devices had been implanted in 38 patients, of mean age 60 years. Follow-up ranged from 0.5 months to 3 years. There had been one extrusion (2.5%) and four cases (10%) where a device had been removed due to melt-related complications. All five of these cases received a donor corneal graft after the device was removed, with these grafts remaining anatomically satisfactory and epithelialised to date. Corneal melts in AlphaCor recipients were found to be strongly associated with a history of ocular herpes simplex infection. Two further devices (5%) were removed owing to reduced optic clarity after presumed drug-related deposition, and have been successfully replaced with second devices. Mean preoperative best-corrected visual acuity was hand movements. Visual acuities after surgery ranged from PL to 6/6(-2) (20/20(-2)).

CONCLUSIONS

Early results suggest that the AlphaCor, previously known as the Chirila keratoprosthesis (Chirila KPro), has a low incidence of the complications traditionally associated with keratoprostheses and can be effective in restoring vision in patients considered untreatable by conventional corneal transplantation. Importantly, the device can be replaced with a donor graft in the event of development of a significant complication. A history of ocular herpes simplex is a contraindication to AlphaCor implantation. Ongoing monitoring of clinical outcomes in all patients will allow the indications for AlphaCor, as opposed to donor grafts, to be determined.

Translocation portals for the substrates and products of a viral transcription complex: the bluetongue virus core

The bluetongue virus core is a molecular machine that simultaneously and repeatedly transcribes mRNA from 10 segments of viral double-stranded RNA, packaged in a liquid crystalline array. To determine how the logistical problems of transcription within a sealed shell are solved, core crystals were soaked with various ligands and analysed by X-ray crystallography. Mg(2+) ions produce a slight expansion of the capsid around the 5-fold axes. Oligonucleotide soaks demonstrate that the 5-fold pore, opened up by this expansion, is the exit site for mRNA, whilst nucleotide soaks pinpoint a separate binding site that appears to be a selective channel for the entry and exit of substrates and by-products. Finally, nucleotides also bind to the outer core layer, providing a substrate sink.

Routine breast screening for women aged 65-69: results from evaluation of the demonstration sites

Routine programme data and specially designed surveys from 3 demonstration sites were analysed to determine the implications of extending the NHS Breast Screening Programme (NHSBSP), to include routine invitations for women up to 69 years. All women aged 65-69 and registered with GPs in these areas received routine invitations for breast screening along with those aged 50-64. Overall uptake was 71% in women aged 65-69 compared with 78% in younger women, but was > or = 90% in both groups who had previously attended within 5 years. Recall rates were lower for older women, but with a higher positive predictive value for cancer. The percentages of invasive cancer in different prognostic categories were similar in the 2 age groups. Older women took no longer to screen than younger women. The costs per woman invited or per woman screened were also similar to those for women aged 50-64, whilst the cost per cancer detected was some 34% lower in older women. Breast screening is as cost effective for women aged 65-69 as for those aged 50-64, with a higher cancer detection rate balancing shorter life expectancy. The proposed extension to the national programme will have considerable workforce implications for the NHSBSP and require additional resources.

Should ambulant patients be directed to reception or triage first?

OBJECTIVES

Developments in triage have led to patients being directed to triage rather than reception upon arrival in A&E. This study aimed to discover if attending triage or reception first, was preferable in terms of timeliness, clarity and safety.

METHODS

The study compared two consecutive four week periods during which patients were directed to attend triage first and then reception first. Observers recorded their actions on arrival. Questionnaires recorded the patients' perceptions of each strategy. High priority triage categories were audited during the reception first phase.

RESULTS

1850 patients were observed in the triage first phase with a mean door to triage time of 10.6 minutes, triage to reception 5.3 minutes and door to reception 15.8 minutes. A total of 1522 patients were observed in the reception first phase with a mean door to reception time of 0.5 minutes, reception to triage 12.4 minutes and door to triage of 12.9 minutes. Patients were more likely to present to the appropriate place during the reception first phase (88% versus 34%) and reported better understanding of instructions. No case given triage category one or two suffered an adverse outcome resulting from delay associated with attending reception first.

CONCLUSION

Directing patients to attend reception first is timely and less confusing. It is safe provided booking in does not delay assessment by more than 15 minutes.

Phase I trial of escalating doses of paclitaxel combined with fixed doses of cisplatin and doxorubicin in advanced endometrial cancer and other gynecologic malignancies: a Gynecologic Oncology Group study

PURPOSE

The primary objective of this phase I trial was to determine the feasibility of administering a combination of paclitaxel, cisplatin, and doxorubicin with or without granulocyte colony-stimulating factor (G-CSF) in patients with advanced endometrial and other gynecologic cancers.

PATIENTS AND METHODS

Patients were chemotherapy-naive. Doxorubicin was administered as a brief infusion, paclitaxel for 3 hours, and cisplatin for 60 minutes. Treatments were repeated every 3 weeks. For most dose levels, the cisplatin and doxorubicin were fixed at 60 mg/m(2) and 45 mg/m(2), whereas the paclitaxel was escalated in successive cohorts from 90 to 250 mg/m(2). Patients who had received previous radiotherapy to the whole pelvis were escalated separately from those who had not.

RESULTS

Eighty patients received 320 cycles of therapy. When G-CSF was not used, myelosuppression prevented escalation beyond the starting dose for patients with or without previous pelvic radiotherapy. When G-CSF was added, neurotoxicity became dose-limiting for both groups. Ten patients were removed from the study for asymptomatic declines in ejection fraction, but no symptomatic congestive heart failure was observed. Major antitumor responses occurred in 46% of patients (six of 13) with measurable endometrial carcinoma and 50% of patients (eight of 16) with measurable cervical carcinoma.

CONCLUSION

The combination of paclitaxel, doxorubicin, and cisplatin at relevant single-agent doses is active and feasible with the addition of G-CSF. A regimen of cisplatin 60 mg/m(2), doxorubicin 45 mg/m(2), and paclitaxel 160 mg/m(2) with G-CSF support is recommended for further testing.

N-methyl D-aspartate receptor-mediated bidirectional control of extracellular signal-regulated kinase activity in cortical neuronal cultures

N-Methyl D-aspartate (NMDA) receptor activation of extracellular-signal regulated kinase (ERK) was examined in primary cortical cultures. Tetrodotoxin, NMDA receptor antagonists, or reduced extracellular calcium (0.1 mm) greatly decreased basal levels of phospho-ERK2, indicating that activity-dependent activation of NMDA receptors maintained a high level of basal ERK2 activation. This activity-dependent activation of phospho-ERK2 was blocked by pertussis toxin and inhibition of calcium/calmodulin-dependent kinase II and phosphatidylinositol 3-kinase but not by inhibition of protein kinase C or cAMP-dependent protein kinase. Addition of a calcium ionophore or 100 microm NMDA decreased phospho-ERK2 in the presence of 1 mm extracellular calcium but enhanced phospho-ERK2 in 0.1 mm extracellular calcium. The reduction in basal phospho-ERK2 by 100 microm NMDA was also reflected as a decrease in phospho-cAMP response element-binding protein. Inhibition of tyrosine phosphatases and serine/threonine phosphatases protein phosphatase 1 (PP1), PP2A, and PP2B did not prevent the inhibitory effect of NMDA. In the presence of tetrodotoxin, NMDA produced a bell-shaped dose-response curve with stimulation of phospho-ERK2 at 10, 25, and 50 microm NMDA and reduced stimulation at 100 microm NMDA. NMDA (50 microm) stimulation of phospho-ERK2 was completely blocked by pertussis toxin and inhibitors of phosphatidylinositol 3-kinase and was partially blocked by a calcium/calmodulin-dependent kinase II inhibitor. These results suggests that NMDA receptors can bidirectionally control ERK signaling.

A phase III trial of ifosfamide with or without cisplatin in carcinosarcoma of the uterus: A Gynecologic Oncology Group Study

OBJECTIVE

The aims of this study were to substantiate the previously reported activity of ifosfamide in patients with advanced, persistent, or recurrent carcinosarcoma (mixed mesodermal sarcoma) of the uterus, and to determine whether the addition of cisplatin results in an improved response or survival. Secondarily, we sought to determine the toxicity of ifosfamide-cisplatin in this patient population.

METHODS

Patients were randomized to receive ifosfamide (1.5 g/m(2)/day) times 5 days every 3 weeks for eight courses with mesna uroprotection, with or without cisplatin (20 mg/m(2)/day) times 5 days. No patient had received previous chemotherapy.

RESULTS

Of 224 patients entered on this study, 30 were ineligible for a variety of reasons, leaving 194 evaluable patients. Early in the study, the dose of the combination regimen was reduced by 20% (1 day) because of toxicity. The investigational arms were balanced for age, grade, and Gynecologic Oncology Group performance status. Percentages of adverse effects reported in 191 patients receiving chemotherapy included (ifosfamide/cisplatin-ifosfamide) grade 3 or 4 granulocytopenia (36/60), grade 3 or 4 anemia (8/17), grade 3 or 4 central nervous system toxicity (19/14), and grade 3 or 4 peripheral neuropathy (1/12). Treatment may have contributed to the deaths of 6 patients treated with full doses of ifosfamide and cisplatin for 5 days. The proportion of patients responding to ifosfamide alone versus ifosfamide-cisplatin therapy was (0.36 versus 0.54) overall, 0.47 versus 0.61 for pelvic, 0.21 versus 0.54 for lung, and 0.33 versus 0.40 for "other" metastatic sites of measurable disease. The relative odds ratio of response adjusted for measurable sites of disease was 1.82 (P = 0.03, one-tailed test; 95% lower confidence limit, 1.06). Progression-free survival (PFS) and survival data suggest that the combination offers a slight prolongation of PFS (relative risk, 0.73; 95% upper confidence limit, 0.94; P = 0.02, one-tailed test), but no significant survival benefit (relative risk, 0.80, 95% upper confidence limit, 1.03; P = 0.071, one-tailed test).

CONCLUSION

The addition of cisplatin to ifosfamide appears to offer a small improvement in progression-free survival over ifosfamide alone in the management of advanced carcinosarcoma of the uterus; the added toxicity may not justify the use of this combination.

A bacterial genome in flux: the twelve linear and nine circular extrachromosomal DNAs in an infectious isolate of the Lyme disease spirochete Borrelia burgdorferi

We have determined that Borrelia burgdorferi strain B31 MI carries 21 extrachromosomal DNA elements, the largest number known for any bacterium. Among these are 12 linear and nine circular plasmids, whose sequences total 610 694 bp. We report here the nucleotide sequence of three linear and seven circular plasmids (comprising 290 546 bp) in this infectious isolate. This completes the genome sequencing project for this organism; its genome size is 1 521 419 bp (plus about 2000 bp of undetermined telomeric sequences). Analysis of the sequence implies that there has been extensive and sometimes rather recent DNA rearrangement among a number of the linear plasmids. Many of these events appear to have been mediated by recombinational processes that formed duplications. These many regions of similarity are reflected in the fact that most plasmid genes are members of one of the genome's 161 paralogous gene families; 107 of these gene families, which vary in size from two to 41 members, contain at least one plasmid gene. These rearrangements appear to have contributed to a surprisingly large number of apparently non-functional pseudogenes, a very unusual feature for a prokaryotic genome. The presence of these damaged genes suggests that some of the plasmids may be in a period of rapid evolution. The sequence predicts 535 plasmid genes >/=300 bp in length that may be intact and 167 apparently mutationally damaged and/or unexpressed genes (pseudogenes). The large majority, over 90%, of genes on these plasmids have no convincing similarity to genes outside Borrelia, suggesting that they perform specialized functions.

Phase III randomized study of cisplatin versus paclitaxel versus cisplatin and paclitaxel in patients with suboptimal stage III or IV ovarian cancer: a gynecologic oncology group study

PURPOSE

To assess progression-free survival (PFS) and overall survival (OS) in patients with suboptimally debulked epithelial ovarian cancer receiving cisplatin (100 mg/m(2)) or 24-hour infusion paclitaxel (200 mg/m(2)) or the combination of paclitaxel (135 mg/m(2)) followed by cisplatin (75 mg/m(2)).

PATIENTS AND METHODS

After stratification for disease measurability, patients were randomized to receive six cycles of one of the treatments every 3 weeks. If measurable, complete response (CR) or partial response (PR) was determined.

RESULTS

Six hundred fourteen of 648 patients who entered onto the trial were eligible. Monotherapies were discontinued more frequently (cisplatin because of toxicity or patient refusal [17%], and paclitaxel because of progression [20%]) compared with the combination therapy (7% and 6%, respectively). Neutropenia, fever, and alopecia were more severe with paclitaxel-containing regimens; whereas anemia, thrombocytopenia, neurotoxicity, nephrotoxicity, and gastrointestinal toxicity were more severe with cisplatin-containing regimens. The CR/PR rates on paclitaxel monotherapy were significantly lower compared with the cisplatin regimens (42% v 67%, respectively; P <.001). The relative hazard (RH) of first progression or death was significantly greater among those randomized to paclitaxel (RH = 1.41; 95% confidence interval [CI], 1.15 to 1.73; P <.001) when compared with cisplatin; however, RH did not differ significantly between the two cisplatin regimens (RH = 1.06; 95% CI, 0.895 to 1.30). Relative to cisplatin, the death rate on paclitaxel was 15% greater (RH = 1.15; 95% CI, 0. 929 to 1.42), and the death rate on the combination treatment was 1% less (RH = 0.99; 95% CI, 0.795 to 1.23). These differences among treatment groups were not statistically significant (P =.31).

CONCLUSION

Cisplatin alone or in combination yielded superior response rates and PFS relative to paclitaxel. However, OS was similar in all three arms, and the combination therapy had a better toxicity profile. Therefore, the combination of cisplatin and paclitaxel remains the preferred initial treatment option.

Detection of endometrial adenocarcinoma in two asymptomatic postmenopausal women receiving tamoxifen. A report of two cases

BACKGROUND

Tamoxifen has been linked to an increased risk for the development of endometrial adenocarcinoma. The majority of these carcinomas present with postmenopausal bleeding. The current standard is to undertake sampling only after the onset of bleeding.

CASES

Two cases illustrate the utility of transvaginal saline infusion sonohysterography (TVS/SIS) in the detection of endometrial carcinoma prior to the onset of bleeding.

CONCLUSION

Annual TVS/SIS may be useful for screening asymptomatic, tamoxifen-exposed patients with a uterus in situ and is likely to be more acceptable to such patients than annual biopsies.

FIGO stage IIIC endometrial carcinoma with metastases confined to pelvic lymph nodes: analysis of treatment outcomes, prognostic variables, and failure patterns following adjuvant radiation therapy

OBJECTIVES

This study was undertaken to evaluate the prognostic significance of isolated positive pelvic lymph nodes on survival and to analyze other prognostic variables, overall survival, and failure patterns in surgically staged endometrial carcinoma patients with positive pelvic lymph nodes and negative para-aortic lymph nodes following radiation therapy (RT).

METHODS

Between January 1, 1987, and December 31, 1997, 782 women underwent primary treatment for uterine cancer at Indiana University Medical Center. Through a review of the medical records, we identified 58 patients with pathologic stage IIIA, 27 patients with pathologic stage IIIB, and 77 patients with pathologic stage IIIC endometrial carcinoma. Patients with pathologically positive or unsampled para-aortic lymph nodes and patients who received preoperative radiation therapy were excluded, leaving a study group of 17 patients with nodal metastases confined to pelvic lymph nodes. Thirteen patients received adjuvant pelvic RT using AP-PA or four-field technique. A median dose of 5040 cGy was delivered. Four patients received whole abdominal irradiation (WAI) delivering a median dose of 3000 cGy. Two patients received vaginal cuff boosts of 1000 and 3560 cGy to 0.5 cm from the vaginal surface mucosa via Cs-137 brachytherapy. Two patients also received adjuvant chemotherapy (cis-platinum and doxorubicin) and/or hormonal therapy (megestrol acetate). Disease-free and overall survivals were estimated using the Kaplan-Meier method of statistical analysis and prognostic variables were analyzed using the log-rank test.

RESULTS

With a median follow-up of 51 months the actuarial 5-year disease-free survival was 81% and the actuarial 2-year and 5-year overall survival rates were 81 and 72%, respectively. Univariate analysis revealed that positive peritoneal cytology in conjunction with positive pelvic lymph nodes imparts a greater risk of recurrence and decreased overall survival. There were no pelvic and/or upper abdominal failures, but there were recurrences in the para-aortic lymph nodes (two patients) and distantly (two patients).

CONCLUSION

Surgery followed by postoperative pelvic RT is a viable treatment option for pathologically staged stage IIIC endometrial carcinoma with disease confined to the pelvic lymph nodes. Failures in the para-aortic region suggest a possible role for extended-field RT. Patients with positive peritoneal cytology in conjunction with nodal metastasis fared poorly with pelvic RT. Studies evaluating the efficacy of WAI are ongoing. Finally, substages within FIGO stage IIIC are recommended in an effort to better understand and define treatment strategies which might be appropriate for these patients.

Phase II trial of paclitaxel in leiomyosarcoma of the uterus: a gynecologic oncology group study

OBJECTIVE

The aim of this study was to determine the activity of paclitaxel in chemotherapy-naive patients with advanced or recurrent uterine leiomyosarcoma.

METHODS

Patients received 175 mg/m(2) of paclitaxel iv over 3 h. Courses were repeated every 3 weeks until disease progression or adverse side effects supervened.

RESULTS

Thirty-four women were entered, but 1 patient was ineligible because of wrong cell type. Median age was 55 years (range: 35-84 years). GOG performance status was 2 in 2 instances, 1 in 9 cases, and 0 in 22 others. Eight patients (23.4%) had received radiotherapy. A median of 2.5 courses was given (range: 1-18). Eleven patients (33.3%) experienced grade 3 or 4 neutropenia, 1 (2.9%) had grade 4 thrombocytopenia, and 1 had grade 3 anemia. There were no cases of grade 3 or 4 gastrointestinal or dermatologic toxicity. One patient each developed deep venous thrombosis and a grade 3 allergic reaction. Eight patients (24.2%) had stable disease for at least 2 courses of therapy. Three complete responses were reported (9.1%).

CONCLUSION

With the dose and schedule tested, paclitaxel has limited activity in patients with uterine leiomyosarcoma. Modest toxicity suggests that a higher dose of paclitaxel might be evaluated.

Fyn tyrosine kinase reduces the ethanol inhibition of recombinant NR1/NR2A but not NR1/NR2B NMDA receptors expressed in HEK 293 cells

NMDA receptors are potentiated by phosphorylation in a subunit- and kinase-specific manner. Both native and recombinant NMDA receptors are inhibited by behaviorally relevant concentrations of ethanol. Whether the phosphorylation state of individual subunits modulates the ethanol sensitivity of these receptors is not known. In this study, the effects of Fyn tyrosine kinase on the ethanol sensitivity of specific recombinant NMDA receptors expressed in HEK 293 cells were investigated. Whole-cell mode patch clamp and ratiometric calcium imaging demonstrated that the degree of ethanol inhibition of NR1/NR2B receptors was unaffected by Fyn tyrosine kinase. In contrast, the inhibition of NR1/NR2A receptors by ethanol (100 mM) was significantly reduced under conditions of enhanced Fyn-mediated tyrosine phosphorylation of the NR2A subunit. This effect was not observed at lower concentrations of ethanol (< or = 50 mM). These results suggest that tyrosine phosphorylation of specific NMDA receptors by Fyn tyrosine kinase may regulate the sensitivity of these receptors to the sedative/hypnotic concentrations of ethanol.

Chronic ethanol upregulates NMDA and AMPA, but not kainate receptor subunit proteins in rat primary cortical cultures

The present study examined the effects of chronic ethanol exposure on the expression of N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxalone (AMPA) and kainate receptor subunit proteins in rat cortical neuronal cultures grown in media containing 2 mM (high) or 0.1 mM (low) glutamine. Immunoblot analysis of NMDA (NR1, NR2A, NR2B, and NR2D), AMPA (GluR1 and GluR2/3), and kainate (GluR6/7) subunit polypeptides in 3-, 5-, 8-, 10-, and 12 day-old-cultures showed that NMDA receptor subunits NR1, NR2A, and NR2B and AMPA receptor subunits GluR2/3 progressively increased as a function of time, whereas levels of NMDA subunit NR2D were high at day 3 and progressively declined to barely detectable levels by day 12. Levels of AMPA subunit GluR1 and the kainate subunit GluR6/7 remained stable throughout the time course. Replacing the culture media with low glutamine media at culture day 5 did not alter the levels of subunit proteins measured at culture days 9 and 13. However, exposure of low glutamine cultures to 100 mM ethanol for 4 days (starting at culture day 9) significantly increased the levels of NMDA receptor subunits (NR1, NR2A, and NR2B) and AMPA receptor subunits (GluR1 and GluR2/3), but had no effect upon kainate receptor subunits (GluR6/7) or the synapse-associated proteins synapsin I and PSD-95. In contrast, chronic ethanol did not alter the levels of any of these subunit proteins in cells grown in high glutamine. These data demonstrate that under certain experimental conditions, prolonged exposure to ethanol upregulates NMDA and AMPA receptor subunit proteins, but has no effect upon kainate receptor subunit proteins. Because we have previously shown that acute ethanol can inhibit NMDA and AMPA, but not kainate, receptor function in these cultures, the increase in subunit expression likely reflects an adaptive response to the inhibitory effects of ethanol and suggests that both NMDA and AMPA receptors may play an important role in adaptation of the CNS to chronic ethanol.